вход по аккаунту


код для вставки
Oct. 15, 1946.
Filed July 2e; 1943
' 10 Sheets-Sheet l
t. l5, 194%,
Filed July 28, 1943
10 Sheets-Sheet 2
ä . i
à. 35, wáë.
Filed July 2S, 1943
10 Sheets-Sheet 3
Oct. l5, 1946.
Filed July 28, 1943
10 Sheets-Sheet 4-
Paul. f.“ BAKKER, HERBERT 6. #mer/«MN v
Oct. 15, 1946. '
P. r--.y BARKER Er‘AL
2,409,240 `
Filed July 28, 1943
10 Sheets-Sheet 5
.ma»(É _._M _ ß
_ __
L..._ _
Pa el.
. .aze,Tf
l Oct. l5, 1946.
2,409,240 -
Filed July 28, 1943
10 Sheets-Sheet 7
Oct. 15,v 1946.
P. F.. BARKl-:R ETAL -
Filed July 28, 1943 -
1o sheets-'sheet s
„ia/f, ».4
2,55 n
` q
Fdän Z7 '
Pau; E emerse, fis/esser c. Haz mmv
aneth/¿E 7.' GnuowAY a BERN/»go MKV/ves
t. E5, 1946.
Filed July 2s, 1943
1o` sheets-sheet 9
cmu-Nc: z @mow/w a emmen Mk1/Nes
Oct 15, 1946..
y 21,409,240.
med July 2a, 194s
1o sheets-Sheet 1o
/1 â Gîtorneg
Patented Oct. 15, 1946
'iss erst orgie
Paul F. Barker, Herbert G. Hartman, Clarence T.
Galloway, and Bernard M. Kunes, Rochester,
N. Y., assignors to Gleason Works, Rochester,
N. Y., a corporation of New York
Application July 28, 1943, Serial No. 496,452
30 Claims.
(Cl. 12S-«11)
2 .
The present invention relates to methods and
to mechanisms for dressing grinding wheels and
particularly to a method and mechanism for
dressing wheels that are to be used for grinding
dressing tool is moving across one side of the
grinding Wheel to dress the same, from top to
In a more speciíic aspect, the invention
relates to methods and apparatus for dressing
bottom, the other side-dressing tool is moving
across the other side of the grinding wheel to
dress the same from bottom to top, and the end
dressing tool is moving across the tip of the Wheel
rotary annular grinding Wheels such as are em
from one side to the other to dress the tip and
to form the desired rounds at the junctures of
the sides and the tip. NOW the height of the
In conventional generating-type spiral bevel 10 sides of a wheel is greater than the Width of the
tip of a wheel because the height of the sides of
and hypoid gear-grinders, the grinding Wheel is
the teeth of a gear is greater than the width of
mounted on an oscillatory cradle that is rotated
the bottom of its tooth spaces and the wheel,
in time with the rotation of the work to produce
of course, has to be commensurate with the gear
the generating motion. To grind gears of dif
to be ground, AsV a result in conventional types
ferent spiral angles, the Wheel has to be adjusted
of dressing mechanisms, the tool for dressing the
on the cradle angularly about the cradle axis,
tip of the wheel moves more slowly than the
and the wheel-dressing mechanism ls mounted
tools for dressing the sides of the Wheel. Conse
to be adjustable with the Wheel so as to be in
quently, the tip-dresser dresses a finer surface
operative relation with the wheel in any position
of angular adjustment of the wheel. The dress 20 on the rounds and on the tip of the wheel than
the surfaces dressed on the sides of the Wheel by
ing mechanism is usually mounted to be adjust
the side dressers.
able around the periphery of the- Wheel to posi
This is of no consequence in the automotive
tion it as far as possible away from the work, but
ployed in the generating-grinding of spiral bevel
and hypoid gears.
even so diñiculty has been experienced on some
field, for the bottoms of the tooth spaces of auto
jobs in obtaining sufficient clearance between the
dressing mechanism and the Work or its support
during grinding. This has limited the capacity
of the grinders despite the fact that otherwise
the machines might be capable of handling a
greater range of Work.
The dressing mechanism itself consists ordinar
ily of a pair of side dressers for dressing the
motive gears and the ñllets, which join the bot
that they perform and complete their dressing
operations simultaneously; that is, while a side
One object of the present invention is to pro
vide a dressing mechanism in which the side and
toms with the sides of the tooth spaces, are not
ground. In the aeroplane iield, however, gears
are heavily loaded, and to eliminate surface
cracks which may become points of incipient
breakage, the tooth space bottoms and the ñllets
are ground. We have discovered that if the tip
and rounds on a Wheel are dressed too ñne, the
fillets and bottoms of the tooth spaces are likely
inside and outside surfaces of the wheel, respec
to be burned when the gears are ground. This is
tively, and of a tip dresser for dressing vthe tip
surface of the Wheel and the rounds at the 35 dangerous because a burned surface is a surface
already full. of cracks and ripe for breakage under
junctures of the side surfaces With the tip. In
dressing, a diamond, or other hard surfaced tool,
We have discovered another factor, also, that
is moved across the wheel surface to be dressed
must be taken into consideration in the dressing
while the Wheel is rotated on its axis at high
speed, usually at the same speed as is employed 40 or” annular grinding wheels. We have found that
Where an annular grinding wheel is rotated at
during grinding. In the dressing operation then,
high speed the wheel tends to expand under
the dressing tool actually turns a helix in the
centrifugal force and to press the outside sur
wheel surface being dressed. The lead of this
face of the wheel against the longitudinally con
helix, that is, the rate at which the dressing tool
is moved across the rotating Wheel, determines 45 cave side ci a tooth space being ground thereby
with greater pressure than that with which the
the iinish of the dressed surface. The faster the
inside surface of the Wheel engages the convex
movement of the dressing tool, the coarser the
side of that tooth space. As a result, we have
dressed surface. For a fine surface finish, the
further discovered that if the outside surface of
dressing tool must be moved at a relatively slow
50 the wheel is dressed to the same fineness as is
required on the inside surface of the Wheel, then
In the machines heretofore built, the side and
the outside surface of the Wheel Will burn the
tip dressers have been operatively connected to
work, and again disaster may follow.
gether either mechanically or hydraulically so
end dressers are actuated simultaneously but in
which the rates of travel of the side and end
dressers can be controlled independently of each
Another object of the present invention vir to
provide a method and apparatus for dressing
ed readily for dressingr Wheels of various di
ameters, heights, pressure angles, and proñle
grinding wheels in which the tip surface of the
wheel and the rounds, which join the tip with
the sides, may he dressed simultaneously with
Other objects of the invention will be apparent
hereinafter from the specification and from the
recital of the appended claims.
The dressing mechanism of the present inven
tion in its preferred form is similar to prior types
of dressing mechanisms in that it comprises three
the sides but to a finish sufliciently coarse as not 10 swinging arms, one of which carries a diamond
to burn the work.
for dressing the tip of the Wheel and the other
Another object of the invention is to provide a
method and apparatus for dressing grinding
wheels With which the tip of the wheel may be~
two of which carry diamonds for dressing the
outside and inside surta es of the wheel, respec
tively. The arms. which carry the inside and
dressed to a iinish which is no finer than the sur 15 outside dressers, are actuated, as in prior types
faces dressed on the sides of the wheel.
of dressing mechanisms, from a single fluid-pres
A further object of the invention is to provide
sure operated piston which is provided on oppo
a dressing process and apparatus for dressing
site sides with racks that mesh with spur pinions
annular grinding wheels in which the outside and
that are secured to the dresser arms.
inside surfaces of the wheel may be dressed to dif
The arm, which carries the end dresser, is
ferent degrees of ñnish, the outside surface be
actuated by a second fluid-pressure operated pis
ing dressed to a coarser ñnish than the inside
ton through a rack, which is secured to that pis
surface, to compensate for and counteract the
ton, and a pinion which is secured to the arm
eiîect of centrifugal force on the wheel in use.
and which meshes with the rack.
Another object of the invention is to dress the 25
The actuating piston for the side dresser arms
sides and tip of a grinding wheel so that it will
is mounted in a block which, in turn, is angu
grind tooth sides and tooth space bottoms on a
larly and rectilinearly adjustable on a swineable
gear which will have substantially uniform sur
bracket. The angular adjustment is for position
face ñnish.
ing the side dressers in accordance with the de~
Still another object of the invention is to dress 30 sired pressure angles of the outside and inside
the sides and tip of a grinding wheel so that the
surfaces of the wheel to be dressed. There are
wheel can be used to grind gears faster without
two rectilinear adjustments, one in the direction
danger of burning than they can be ground by
of the wheel axis and the other in a direction at
conventionally dressed wheels.
right angles thereto. The ñrst serves to position
A further object of the invention is to provide 35 the mean point of swing of the diamonds with
a dressing mechanism having side and tip
relation to the heights of the active side surfaces
dressers in which the dressers may be swung
away from the grinding wheel on completion of
the dressing operations so as to clear the wheel
and permit of grinding any gear within the ca
pacity of the machine on which the dressing
mechanism is used without danger of interfer
ence oi‘ the dressingr mechanism with the work
or its support.
A further object of the invention is to provide
a dressing mechanism having separate side and
tip dressers in which a single control valve may
be employed to control the movements of the
side and tip dressers to and from operative posi
of the wheel.
The second is for the purpose of
positioning the diamonds in accordance with the
diameter of the wheel to be dressed. The swing
able bracket is pivotally mounted on a slide which
is adjustable rectilinearly on a ring-like support
in a direction at right angles to the directions
of the two previously described rectilinear adjust
ments, and is for the purpose ci positioning the
. dressing mechanism to dress selectively concave.
convex, or substantially straight line proñlcs en
the grinding wheel, in accordance with the prin
ciples 0f Wildhaber et al. Patent No. 2,311,302.
issued February 16, 1943. The ring-like support
tion as Well as the operation of these dressers 50 is mounted coaxially with the grinding wheel axis
when in operative position.
and is adjustable about the axis in accordance
Another object of the invention is to provide
with prior practice to permit positioning the
a dressing mechanism in which the mechanism
dressing mechanism at a point around the grind
for advancing the wheel in accordance with the
ing wheel remote from the point of engagement
amount of stock to be dressed off of the wheel
of the wheel with the werk. The pivotal move
is controlled from the same valve which controle 55 ment of the bracket on the slide serves, however,
the operations of the dressing mechanism itself.
to swing the dressers into or out of operative re
Another object of the invention is to provide a
lation with the grinding wheel.
tip dressing mechanism capable of dressing a
The end dresser arm and the piston, which ac
straight tip surface on a wheel with rounds at
tuates the same, are pivotally mounted on a slide
the junctures of the tip with the sides of the
for movement about an axis that extends at right
wheel in a single continuous movement and
angles to the axis of swing of this arm. The slide,
which will be simpler and cheaper than tip
in turn, is mounted on a bracket for adjustment
dressing mechanisms of this character hereto
fore employed.
rectilinearly in two directions at right angles t0
one another to position the end dresser in ac
A further object of the invention is to provide 6 cordance with the diameter of the wheel to be
a dressing mechanism for dressing the sides and
dressed and in accordance with the height of the
tip of a grinding Wheel, in which the dressing
wheel. The bracket itself is adjustable angularly
tools will be moved back and forth across the
on the ring-like support above mentioned so that
surfaces to be dressed, and in which the rate of
movement of the dressers in one direction will 70 like the side-dressers the end dresser may be po
sitioned at a convenient point about the periph
be faster than in the opposite direction, so as to
ery of the wheel to provide maximum clearance
provide first a rough-dressing operation and
between the end dresser and the work.
then a finish-dressing operation.
A still further object of the invention is to pro
The pivotal movement of the bracket, which
vide a dressing mechanism which can be adjust 75 carries the end dresser, serves two purposes, viz.,
to move the dresser into and out of operative posi
tion, and to control the shape produced on the
tip surface of the grinding Wheel when the dresser
is in operative position. In its latter function,
the pivotal movement of the bracketv serves to
operation ofl the other parts of the dressing
mechanism. The feed piston isactuated to ad
vance-the wheel during swing of the side and end
dressers into operative position.
‘ In the drawings:
Fig. 1 is an elevational view looking at the
wheel end of a spiral bevel gear grinding machine
of known construction and showing a dressing
mechanism constructed according to one embodi
the tip of the wheel.
‘ The pivotal movements of the brackets, which 10 ment of the present invention mounted thereon;
Fig. 2 is part plan, part transverse sectional
carry the side and end dressers into and out of
view of the parts shown in Fig. 1;
operative relation with the wheel, are effected by
ì Fig. 3 is a fragmentary view, partly in elevation
separate pistons which are controlled from a
and partly in. section, on an enlarged scale, show
single valve to operate simultaneously together.
This control valve also governs the operation of 15 ing the end dressing mechanism in operative re
lation to the grinding wheel;
the pistons which actuate the side and end dress
‘i is a section on the line 4_5 of Fig. 3 on
ers when the dressers are in operative position.
an enlarged scale, looking in the direction of the
The control valve is moved step-by-step iirst
in one direction and then in the other. During
Fig. 5 is a view of the end dressing mechanism
grinding of a. gear. the side and end dressers are 20
looking in the direction oi the arrow 5 in Fig. 3;
out of operative position. When it is desired to
Fig. 6 is a fragmentary sectional view showing
dress the grinding wheel, the control valve is
how the end dressing mechanism is mounted on
moved part-way in one direction to cause the
supporting ring` which surrounds the grind
side and end dresser brackets to be swung above
their pivots to carry the side and end dressers 25 ing wheel spindle, and illustrating some of its
into operative relation with the wheel. When
Fig. 7 is a Jfragmentary view in plan showing
this position is reached, the control valve is
swing the dresser, independently of its swinging
movement from one side of the wheel to the
other, and permits of dressing a plane surface on
moved the rest of the way in this same direction
the pivotal bracket for carrying the side dressing
mechanism, its mounting, and the means for ac
ers, to be moved to effect rough-dressing of the 30 tuating the same;
Fig. 8 is an elevational View on a somewhat
sides, tip and r‘ounds on the wheel by movement
smaller scale of the parts shown in Fig. 7, por
of the dressers in one direction across the grind
tions being bro-ken awayV and shown in‘section:
ing wheel. The control valve is then moved back
Fig. 9 is a view, partly in section and partly in
one step in the opposite direction, causing the
elevation, showing the mechanism for swinging
side and end dressers to swing back across the
the side-dresser bracket about its pivot'and its
sides and tip of the wheel to eiiî‘ect ñnish dress
connection with the bracket;
ing thereof. Then the operator moves the con
Fig. l0 is a sectional view en an enlarged scale
trol valve back the second step to its original po
further illustrating the connection between the
sition, causing the side and end dresser brackets
to be moved about their pivots to move the side 40 side dresser bracket and the piston which swings
the bracket to and from operative position;
and end dressers out of operative position to clear
Figs. 11 and 12 are detail views, taken at right
the work when the wheel is in use.
angles to one another, showing the lost-motion
Check and throttle valves, which are incorpo
connection between the outside dresser arm and
rated in one side of the lines; of both the piston,
which actuates the side dresser, and the piston, 45 the cam which controls the aXial movement of
that arm;
which actuates the end dresser, serve to control
Fig. 13 is a sectional view of the shuttle valve
the rates of movement of each piston in one di
which permits of operation of the end dressers
rection. so that the pistons may be operated at
independently of the side dressers;
slower speed during their return movements from
Figs. 14 to 16 inclusive are diagrammatic views
that during their forward movements. This per
illustrating the operation of the valve which con
mits of roughdressing on the forward move
trols the operation of the whole dressing mech
ments and finish-dressing on the return move
ments. A reversible shuttle valve permits of the
Fig. 17 is a developed view of this valve;
movement of the end dresser piston to be inde
pendent of the movement of the side dresser pis 55 Fig. 18 is a diagrammatic View showing the
hydraulic circuit to the various parts of the dress
ton with the result that the end dresser may be
ing mechanism;
moved at any desired rate with reference to the
Fig. 19 is a section on the line lS-IS of Fig.
side dressers in both directions and may produce
any desired iinish on the tip of the grinding
Figs. 20 and 21 are diagrammatic views illus
trating the action of the side and end dressers
A lost motion device, comprising a ball and an
in the successive steps of rough-dressing and
inclined raceway for the ball, serves to shift the
causing the two pistons, which actuate the dress
axial position of the arm which carries the out
side dresser, .when the arm reverses at the ends
nnish-dressing, respectively;
‘ i
tools to compensate for wheel wear, a ratchet and
tip surface on the wheel.
Reference will now be had to the drawings for
a more detailed description of the invention.
Fig. 22 is a view corresponding to Fig. 21 but
of its swing. Thus, the arm may be displaced 65 illustrating diagrammatically the operation when
the outside dresser is in withdrawn position on
axially and the outside dresser may clear the
its return stroke; and
wheel on its return stroke. Thus, the outside
Fig. 23 is a diagrammatic view illustrating par
surface of the wheel may be rough-dressed only
ticularly how the tilting movement of the end
to avoid burning of the gear tooth surface which
is ground by the outside of the wheel.
70 dresser during a part of its swing from ’one side
of the wheel to the other serves to dress a iìatv
To produce feed of the wheel into the dressing
pawl mechanism is provided. This is actuated
by a huid-pressure operated piston which is con
trolled from the same valve which controls the 75
25 (Fig. 2) denotes the tool spindle of a grinding
machine off known construction. 2,5 is a sleeve
member in which the tool spindle is journaled.
be effected preciselyvby` use of the pointerÍ 12
W denotes a grinding wheel which is secured to
which reads against graduations enscribed on one
side of plate 55. The plate G5 is secured in any
the tool spindle by, for instance, a clamping disc
2ï and a bolt 28.
The wheel W is a rotary an
nular wheel having active outside and inside sur
faces 3|> and 32, respectively, which are inclined
to the axis of the wheel, and a tip surface 33,
whichl ordinarily is perpendicular to said aXis.`
(Fig. 9) which is secured» to the plate‘65 and
position of adjustment on the plate 55 by
T-bolts 69 (Fig. 2) which pass through elongated
slots 1€) in the plate 55 and engage in T-slots 1|
formed in the upper face of the plate 55.
Mounted on the plate 65 for angular adjust
For clearness of illustration, the grinding wheel 10 ment thereon is a housing 15 (Figs. 1 and 2).
shown in Fig. 1 is somewhat smaller in diameter
Angular' adjustment of this housing is effected by
than the grinding wheel shown in Fig. 2.
There is a ring member 35 mounted on the
rotation of a worm shaft 'I6 which is journaled
in a block 1l that is doweled or otherwise fas
flange portion 29 of sleeve 26 behind the grind
tened to the, plate 55. The worm shaft 'IS carries
ing wheel. This ring member supports the dress 15 a worm 73 which meshes- with a worm wheel
ing mechanism and is adapted to be adjusted on
segment 18 that is fastened to the housing '15.
the sleeve 26 about the axis of the wheel to po
The housing 15 is guided in its angular adjust
sition the -dressing mechanism at Whatever point
ment on the plate 65 by a tongue 'I9 which ls
may be most convenient to clear the work. It is
formed on the under face of the housing and
secured in any adjusted position by a hand op 20 which engages in a circular arcuate groove 80
@rated spring-pressed plunger 35 which may be
that is formed on the upper face of the plate 65.
engaged selectively in one of several equi-spaced
A flexible tongue 8i, which is integral with the
holes 31 that are formed in the periphery of the
block il and which is manipulated by the bolt
flange portion 29 of the sleeve 26.
82 and which engages over an arcuate ñange
The ring member> 35 is formed with a lateral
formed integral with thel housing 15, serves to
extension ¿l0 on which is mounted a slide ¿il (Figs.
clamp the housing in any adjusted position.
1, 7, and 8). The slide 4| is adjustable recti
A Vernier 84, that is integral withthe housing 15
linearly on the extension 4i), and its adjustment
and that reads against angular graduations pro
is efîectedby rotation of a screw shaft 42. This
vided> on the upper face of the plate 65, serves to
shaft is journaled in a plate 43 and threads into 30 permit of adjusting the housing ’f5 precisely an
the slide 4|. The plate 43 is secured to the ex
gularly on the plate 65.
tension 45'by screws 54 (Fig. 2). The slide 4| is
Journaled on suitable anti-friction bearings .in
guided in its adjustment by a tongue 45 which
the housing ’l5 are a pair of shafts 9€? and Si
engages in a T-slot 46 formed in the front face
(Fig. 2). These shafts are mounted in the hous
of the extension 40. An index pointer 41, which
is secured to the slide 4| and Which reads against
graduations enscribed on the face of the project
ing’portion 40, serves to permit of adjusting the
slide‘precisely. T-bolts (not shown), which en
ing so that their axes are inclined to one another
gage iny the T-slot 46, serve to secure the slide
to the ring S5 in any adjusted position.
Piyotally mounted on the slide 4| is a bracket
5i). This bracketis hinged to the slide by av hinge
pin` 5.11 which is journaled in the slide 4| on bear
ings 52 and 53. The means for swinging the
bracket 50 about the hinge pin 5| will be de
scribed hereinafter.
Mounted for rectilinear adjustment on the
angle corresponding to the included angie
between the inside and outside surfaces 3i and
32 of the grinding wheel which is to
The shaft 9d’ carries an arm S2 in which is mount
ed the diamond 53 for dressing the outside sur
face 3i of the grinding wheel, The shaft 9|
arm 95 in which is mounted the dia
mond 5S for dressing the inside surface 32 of the
grinding wheel, The arms 92 and Q5 are shaped
in the conventional manner so that at a mean
point of swing of the arm 95 the diamond 9S
will engage -the inside surface 32 of the wheel at
a point lying in the same radial plane cf the
wheel as the point of engagement of the diamond
53 with the outside surface of the wheel when
bracket 50 in` a-direction at right angles to the
direction of adjustment of the slide 4| is a plate
55.v (Figs. 1 and 9). Adjustment of this plate may 50 the arm 92 is at a mean point of its swing. Fur
be` effected byY rotation of the screw shaft 56
ther, the arms S2 and 95 are shaped and bent
which is journaled in the bracket 50 and which
in the usual manner and the diamonds E? and Sii,
threads into a nut (not shown) that is secured
to the~ pla-te 55. The plate 55 is guided in its ad
respectively, are so mounted in these arms that
each diamond will lie at substantially right angles
justment by a tonguey 51 which engages in a T
slot 52; formed in the upper face of the bracket
to the side surface which it is to dress.
There is a spur gear segment 98 fastened to
591 A Vernier. 55, which is secured to the plate 55
the shaft 95 and there is a spur gear segment §39
(Fig. 1), and a scale 6U, which is secured to one
fastened to the shaft 9i: These segments mesh
side of the bracket 59, serve to permit precise
with racks i535 and lill, respectively. that are cut
adjustment of the plate 55 on the bracket. The 60 into opposite sides of a piston 4D?. The piston
plate is secured to the bracket after adjustment
mi’. is reciprocable in a cylinder |053 (Fig. i8)
by T-bolts (not shown) which engage in the
formed in the housing '55.
parallell T'-slots 58; and 52 (Fig. 9).
The end of the shaft Si', remote from that
Mounted on the plate 55 for adjustment rec
which carries the arm 92, is formed with an in
tilinearly thereonv in a direction at right angles 65 tegral arm
(Figs. 2. 1l and ISI). This arm
to the directions of adjustment of plate 55 and
slide 4| is a plate 65. The plate 65 is guided
in. its adjustment on the plate 55 by a tongue 65
(Fig. 1) which is integral with the plate 55 and
which engages in a groove 5? formed. in the under
face of the plate 65.
Adjustment of the plate
carries a ball |65 which serves as :i follower to
engage the face |61 of a cal . U38 that
in an end plate |69 which is fastened in
able manner to the housing '55.
A coil spring H0, which surrounds n plunger
Hi, serves to hold the ball-follower
the face |57 of the Cain. The plunger is mounted
in a hole drilled in the shaft Sil and the spring
.65 on the plate 55 is effected by rotation of a
screw shaftr 68 which is carried by the plate 65
and whichY threads into a nut (not shown) that
is secured to the plate 55. This adjustment can 75 H0 is interposed between the head H2 of the
plunger and a nut |||| which threads into the
bore of the shaft 93. The plunger ||| is secured
in the housing 15 by a nut | I3 which threads onto
the outer end of the plunger.
The ball |05 is mounted in a raceway ||5 (Fig.
ll) whose internal diameter is somewhat larger
than the diameter of the ball, and the ball is
adapted to ride on the inclined surface H5 of a
is secured by a pressed ñt or otherwise in the
bracket. The keeper |28 is pivotally connected
to the end cap |21 by means of the hinge pin |35`v
and it is secured in engagement with the pin |29
by the hinge bolt | 3| and the nut |32.
bolt |3| is pivoted on the cover plate |21 by means
of the pin |33, and the nut |32 threads Onto the
hinge bolt |31 to hold the keeper |28 in engage
ment with pin |29~
block ||l` which is mounted in the arm |55. The
The piston |25 is ñxed against movement rela
surface I ||5 is inclined in the direction of rotation 10
tive to the slide é- | . It has a rod portion |35 which
of the shaft e@ so that when the shaft is reversed
projects through the end cap |35 of the cylinder
at the ends of its swing the ball lâlß may ride on
|25 and which threads into a block |31 that is
the surface H6 to allow of axial movement ci
pivotally mounted on a pin |38. The pin |38 is
the shaft. The ball and its mounting constitute,
secured in the slide ¿il against movement relative
therefore, a lost motion device allowing axial
thereto by a set screw |39.
movement of the shaft 95 for a purpose which
Ducts 1de and itl are provided in the end plate
will hereinafter appear in more detail.
|21 and the side wall of the cylinder |23, respec
The shaft Si has an arm H3 (Fig. 2) formed
tively, for admitting fluid under pressure to op
integral with it which is adapted to ride on the
posite ends of the piston |25. When the line
rear face of a cam |2|| that is secured to the
|43 is on pressure, the bracket 53 will be swung
housing i5. The arm | i9 is held in engagement
about the hinge pin 5| (Figs. 7 and 8) to move
with the cam |20 by a coil spring |2| which sur
the side-dressing mechanism out of operative re
rounds the plunger |22. This‘spring is inter
'lation with the grinding wheel, and when the
posed between the head of the plunger and thc
shaft 9|.
25 »duct |ä| is on pressure, the side dressing mecha
nism will be returned again into operative rela
The cams |58 and |23 control the prof-lle shapes
tion with the wheel.
dressed on the outside and inside surfaces, re
The tip surface of the wheel is dressed by a
spectively, of the grinding wheel. The configura
diamond |65 (Figs. l and 2) which is secured in
tions of the active surfaces of these cams deter
mine directly the profile shapes dressed on the 30 an arm Md that has a split-clamp connection
with a shaft H51 (Fig. 3) and that is held against
wheel. Thus the active surface ital’ of cam |33
axial movement relative to this shaft by means
(Figs. l1 and 12) comprises a plane surface |23
of the washer |48. This washer is secured to the
perpendicular to the axis of the shaft 9|) and an
shaft by a screw M9. The shaft |41 is journaled
inclined surface |25?. Hence, the cam |33 will
cause the dressing tool 93 to dress a surface on 35 on suitable bearings |5|l and |5| in the housing
|52. This housing is bored to provide a cylinder
the outside of the wheel of two different pressure
|53 (Figs. 4 and 18) in which there is recipro
angles in accordance with the principles of
cably mounted a piston |54. The piston |515 is
Stewart Patent No. 2,311,262. 1f it is desired to
provided at one side with rack teeth |55 that
dress a straight proiîle of a single pressure angle
from top to bottom, a plane surfaced disc is sub 40 mesh with the teeth of the spur pinion |56 which
is keyed to the shaft |41. Thus, as the piston
stituted for the cam |33 so that no axial motion,
|54 is reciprocated in the cylinder |53, the shaft
other than that produced by the lost motion de
M1 is rocked in one direction or the other to
vice, is imparted to the shaft Si) during dressing.
move the diamond M5 across the tip of the grind
From the structure described, it will be seen
that when the piston HB2 is moved in one direc 45 ing wheel from one side thereof ~to the other to
dress the tip of the wheel and rounds at the
tion or the other in the housing 15, the arms Sil
junctures of the tip with the sides of the wheel.
and 9| will be swung simultaneously in opposite
The housing |52 is mounted to swivel on a
directions to pass the dressing tools 33 and S6
slide |53 for movement about an axis which ex
across the outside and inside surfaces, respec
tively, of the grinding wheel and that during the 50 tends in a direction perpendicular to the axis of
oscillation of the shaft |111. For this purpose,
swinging movements of the arms, am'al move
there is a swivel stud I5! secured in the slide |69
ments may also be imparted to them depending
by a nut |E2 which threads onto the lower end
upon the shapes of the cams |63 and |23, and
of the stud. The housing |52 is mounted on the
also, in the case of the shaft 33, upon the lost
motion device ISG-I i8. Thus by use of suitable 55 stud |5| yby a circular collar |63 which engagesA
under the enlarged head portion |65 of the stud
cams |33 and |25 any desired shapes can be
and which is secured to the housing |52 by the
dressed on the outside and inside surfaces of the
screws |66. A spacing washer |61 is interposed
grinding wheel, and through the lost motion de
between the coilar |53 and the vhousing |52.
vice, the outside dressing diamond can be moved
The housing |52 may be oscillated about the
clear of the outside surface of the wheel on the 69
axis of the centering member |5| for two pur
return stroke of the arm 92 so as to dress on`
poses, namely, to produce a substantially fiat tip
movement `of this arm in one direction only.
surface on the grinding wheel as the end dresser
As has already been stated, bracket 5t is piv
|45 swings from one side to the other of the
otally mounted upon the slide di (Figs. 7 andß).
The pivotal movement of the bracket is for the 65 wheel, and t0 move the end dresser HB5 out of or
into operative relation with the wheel. The first
purpose of swinging the side dressers into and
movement is accomplished by means of a cam |1||
out of operative engagement with the grinding
(Figs. 3 and 5) which engages with a rider or
wheel. The pivotal movement of the bracket is
follower |1í. The cam is mounted for rotatable
produced by a piston |25 (Figs. 9 and 18) which
is mounted to reciprocate in a cylinder |25. One 70 adjustment on a disc |13 that iskeyed to the
shaft |41. The rider or follower |1| is in the
end ofv this cylinder is closed by an end cap |21
form of a pin which is threaded into an upright
(Figs. 9 and 10) which is secured by screws (not
arm |12, that is integral with the slide |65. The
shown) to the cylinder. This end cap is releas
follower has a conical inner end that engages the
ably secured to the bracket 55 by means of a
keeper |23 which engages a headed pin |23 that 75 peripheral surface of the> cam lli). The cam is
secured against rotation relative to the disc |73
by a nut |35 and washer |16. The nut |15
threads on the shaft |51. The adjustment of the
cam on the disc permits of controlling the angle
of inclination to the axis of the grinding wheel
of the tip surface dressed on the wheel. By ad
justing the cam angularly about the axis of shaft
a scale 251 that is fastened to the bracket |95.
After the adjustment is made,»the bracket v|55'is
fastened to the plate 205 by means of the bolt 208
that threads into a Anut 209 which engages »in a
slot 2|0 formed in the upper face of the plate 205.
The bolt 208 is mounted in the thimble 2| | which
is flanged to engage the bracket |95. A lock-nut
|51, the point, at which the housing |52 is rocked
2|2 serves to hold the bolt securely after the ad
justment is made.
by the cam, can be adjusted, so that the plane tip
The .plate v205 is mounted on the ringimember
surface dressed on the wheel can be made per 10
pendicular to the axis of the wheel or can be in
35 for adjustment around the periphery -of the
clined thereto at any suitable angle. Ordinarily
ring member about the axis 'of the wheel spindle.
This adjustment permits of positioning the end
the tip of the wheel is dressed to be perpendicu
lar to a line bisecting the angle between opposite
dresser at any convenientl point around the pe
sides of the wheel. Adjustment of the cam |10 15 riphery of the grinding Wheel so as to minimize
on disc |13 can be made precisely by use of >the
the possibility of interference between the end
pointer l‘i‘i (Fig. l) which -reads against suitable
dressing mechanism and the work even in with
graduations provided on the `periphery of the
drawn position of the end-dressing mechanism.
The plate 225 is secured iii-any adjusted position
The swivel movement of the housing |52 for 20 on the ring member T35 by two T-shaped tongues
movement of the enddresser to and from opera
2|5 (Figs. 3 and 6) 'which engage in a T-shaped
tive .position is eifected by reciprocation of a pis
groove 2|5 formed `on the periphery of the ring
ton :|30 (Figsß and 18) that is reciprocable in a
35 and which serve to guide 'the plate 205 in vits
cylinder |8| `which is vintegral `with the slide |50.
adjustment on Vthe ring. Bolts 2H, which are
The piston |85 is formed .with a rod portion |82 25 carried by plate 205, serve to move the tongues
which projects through the end plate |03 of the
2 t5 intoïand-outof clamping position.
cylinder 58| and which has a threaded and split
The operation of the dressing‘mechanism shown
clamp connection with a coupling piece |84.
in the >dra-wings is controlled by a manually ro
lThis coupling piece |84 "has a pivot'ed connection
tatable valve 220 (Figs. 17 and 18) which is jour
at |85 with a piece |86 into which is threaded a
naled in the sleeve 22| 'that 'is mounted in the
plunger |81. The plunger |81' extends into a
bracket 222. The bracket 222 is secured in any
sleeve |58 which is >pivotally connected by means
suitable position on the grinding machine. The
of the pin |85 (Figs. 3 and 4) with the housing
valve 223 is rotated by Ia -lever 223 which is se
|52. The pin |89 threads into the housing |52.
cured in a head 224 that is pinned to ‘the stern
There is a coil spring |55 -that surrounds the
portion 225of the valve 220. 'The stem portion
plunger |87 and that is interposed between the
225 of the 'valve projects outwardly through the
head of the plunger and a cap |9| which threads
plates 226 that-close-one end of the casing 222.
into the open end of the sleeve |88. The spring
The opposite end ef the casingr is closed by a
tends to hold the Íend dresser in operative posi
plate 221.
tion in combination with the pressure on the
Thevalve is 'formed-on Vits `periphery with two
right hand end of the piston |80 (Fig. 3). When
elongated grooves-230 and with two pairs of short
pressure is applied to the left hand end of the
er-grooves 23| and`252. All of these grooves ex
piston | Sil, however, the end-dressing mechanism
tend axially of the valve. The grooves 230 are
is swung about the pivot stud |6| so that it is
connected, however, by a groove 233 which ex
moved away from >operative relation with the 45 tends aroundthe periphery of the valve.
grinding wheel.
The sleeve 22| (Figs. 14, 15, 16 and 18) is pro
The slide |55 has a dove-tailed portion 250
vided with seven peripheral grooves -235 to 24|
which engages in a correspondingly shaped
inclusive which are equi-spaced axially of the
groove 20| in the bracket |25, and is mounted for
sleeve. Radial ports, which are drilled in the
rectilinear adjustment on a bracket |55 (Figs. 3, 50 sleeve V2.5, communicate with each of these
5, and 6). A gib 202 serves to take up wear.
grooves. Thus, there are four ports 245, commu
The adjustment of the slide is effected by rota
tion of a screw shaft |56 which is journaled in
nicating with Vgroove 235; there are four ports
255, communicating with groove 236; two ports
the bracket |95 and 'which threads into a nut
251, communicating with groove `231; four ports
(not shown) that is secured in the slide. A tubu 55 248, communicating Ywith groove 238; 'four ports
lar guard |57, that is secured to the slide, serves
249, communicating with groove 239; two ports
to protect the threaded portion cf this shaft from
25o, communicating with groove 240; and four
dirt and grit. The adjustment of slide |60 on
ports 25|, communicating with'groove 24|. The
the bracket |25 is provided to permit of proper
different ports of each group Aare spaced angu
positioning of the end dresser in accordance with
60 larly from one another about ‘the axis of the
the diameter of the grinding wheel to be dressed.
sleeve 22| and valve 220 as best shown in the de
This adjustment can be made precisely through
veloped'views of Figs. 14 to 16 inclusive. The
use of the Vernier |98 which is secured to the
shoulders formed on theisle'eve '22| between the
slide E50 and which reads against a graduated
several grooves 235 to '24| inclusive separate the
scale |99 that is fastened to the bracket |95.
65 different groups of ports from one another so
The bracket |95 is adjustable rectilinearly on a
that the motive iiuid may'fiow from one group
plate 205. This adjustment, which is in a, direc
of ports to another only through the grooves 235,
tion at right angles to the direction of adjust-`
ment of the slide |60 on the bracket |95y is for
23|, 232, and 233 of the valve`22ß.
the purpose of positioning the end dresser in ac
The pressure ñuid is supplied to the valve 220
from ducts 255 and 25| (Fig. 18). The duct 250
cordance with the height of the grinding wheel,
that is, in accordance with the axial position of
the tip surface of the wheel. It may be effected
manually under control of a Vernier 206 which is
secured to the plate 205 and which reads against 75
ply. The duct 25| communicates with the groove
238 and ports 2&8 in sleeve 22|. The motive fluid
is exhausted from the valve 225 through the ducts
252 and 253. The duct 252 communicates With
is connected with any suitable source of ñuid sup
the valve through the groove 24| and ports 25|
of sleeve 22 l, and the duct 253 communicates with
the valve through the groove 235 and ports 245
secured in any suitable manner .to the housing 15
and that serves to close one end of cylinder |03.'
of sleeve 22|.
duct 293 is normally closed by a ball check valve
The groove 239 and ports 246 in the sleeve 22|
Communication between the duct `28| and the
281 under actuation of the spring 288.
communicate with a duct 255. This duct is con
nected by means of a duct 255 and a duct 251
The duct 28| is also connected by a duct 290
with one end of a chamber o-r casing 29| (Figs.
with one end of the cylinder I 8| in which the
piston |99 reciprocates that moves the end-dress
i3 and 18) which houses the sleeve 292 and the
valve 293 that reciprocates therein. The valve
293 is normally urged in one direction by a coil
spring 294 which is housed in a bore in the Valve`
and which is interposed between the inner end
of this bore and the cap member 295 which closes
ing mechanism to and from operative position.
The duct 255 is also Connected by means of the
duct 255 and duct |49 with one end of the cyl-
inder |26 in which the piston |25 reciprocates
one end of the valve chamber. The duct 299 is
threaded into the cap member 295 which closes
from operative position. The connection between
the other end of the valve chamber. The sleeve
the duct |49 and the cylinder |26 is controlledby
292 is formed with ñve groups of radial ports.
two ball check valves 259 and 259. The ball check
These ports are denoted at 291, 299, 299, 399 and
valve 253 is normally constrained by a coil spring
99|, respectively. The valve 293 is formed with
252 to prevent ñow of the motive fluid from the
duct |99 into the duct 259 whence it may ilow 20 three axially spaced partition shoulders 303, 39d
and SI15.
into the cylinder |26. The ball check valve 259
The valve 293 is a shuttle valve and serves in
is normally constrained by the coil spring 293 to
the embodiment of the invention illustrated in
prevent flow of the motive fluid from the cylinder
the drawings to permit of movement of the end
|29 through the ducts 299 and 25| into the duct
dresser independently of the side dressers. The
pressure fluid is supplied to the valve -293 from
The duct 255 is also connected with one end
the line 259 through the duct 3|9 which com~
of a cylinder 255 in which a piston 285 is recip
municates with the ports 299 in the sleeve 292.
rocably mounted. The piston 255 is intended to
The motive fluid is exhaustedv from the valve
operate the mechanism for feeding the grinding
cham-ber 295 either through the duct 3| I, which
wheel into the dressers to determine the amount
communicates with the ports 291 in sleeve 292, or
of stock to .be removed from the wheel and to com
the duct 3I2, which communicates with the ports
pensate for wear of the wheel. .The piston 299
39|. The two ducts 3I| and SI2 are connected
may be connected to the feed mechanism of the
that moves the side-dressing mechanism to and
grinding machine in any suitable manner to op
erate same. As shown, it is connected by the pis
ton rod 261 and a link 268 with one arm of an
oscillatable member 259 that is mounted to pivot
to a duct. 953 which leads to the sump of the
grinding machine.
The valve chamber 29| is connected to one end
of the cylinder i153, in which the piston |54 recip
rocates, by a duct 3|5 which communicates'with‘Y
the ports 298 in the sleeve 292. The valve cham
ber 29| is connected to the opposite end of the
cylinder i5@ through a duct 3| 9 which communi
mounted to rotate about the axis 219. This
cates with the ports 399 in the sleeve 292. The
ratchet wheel may be connected, for instance, to
duct 9i E connects with the mentioned end of the
a feed screw that imparts feed movement to the
cylinder |53 either through a duct SI1 or a duct
grinding wheel so that on each reciprocation of
the piston 259 a step-by-step feed movement may 45 3í8. Communication between the duct 3| 6 and
the duct 3|1 is controlled by a normally closed
be imparted to the wheel to feed the Wheel into
ball-check valve SIG that is urged into closed po
the dressers.
sitionby a coil spring 929.- Communication be
The groove-23'! and ports 221 in the sleeve 22|
tween the duct SIB and the duct SIS is controlled
communicate with a vduct 215 which is connected
to one end of the cylinder ISI in which the pis 50 by a needle-valve 92d which threads into the cap
member |51 that closes one end of -the cylin»4
ton |89 reciprocates. This duct 215 is also con
der |53.
nected with one end 0f the cylinder |25 by the
The parts are shown in Fig. 18 in the positions
duct HH, and it is connected with one end of
which they occupy when the side and end-dress
the cylinder 255 b-y the duct 216.
The groove 299 and ports 250 in the sleeve 22S 55 ing mechanisms are out oi operative position.
This corresponds to the position of the valve 229
communicate at opposite sides of the sleeve 22|
which is diagrammatically illustrated in Fig. 14.
with ducts 395 and 951 (Fig. 19). A ball check
In this figure and' in Figs. 15 and 16 the grooves
valve 399 is normally pressed by a coil spring 399
in the valve body are shown in dotted lines oppo
into position to close off communication between
the duct 391 and a duct 289. A needle valve Sie, 60 site the ports of the valve sleeve 22| with which
' the grooves are in communication at differentl
which threads into .the valve casing 222, serves
steps in the rotary movement of the valve. Figs.
t0 control the opening between the duct 289 and
i4, l5 and 16 represent successive positions of the
the duct 395. The duct 289 leads to one end of
about an axis 219. Pivotally mounted on another
arm of the member 269 is a pawl 21| which is
adapted to engage a ratchet ,wheel 212 that is
the cylinder |93 in which the piston |02, that
actuates the side dressers, reciprocates. The op
posite end of the cylinder is connected by the duct
29 I with the groove 239 and ports 229 in the sleeve
valve as it is rotated in the sleeve.
28| is controlled by‘needle valve 285 which is ad
valve body _229, and ports 25| in the valve sleeve
In the position of the valve shown in Figs. 14
and 18, the pressure fiuid flows from the ducts
259 and 25| through the ports 229, grooves 239
and 293, and ports 295 and 299 int-o the ducts
The duct 29| also communicates with the cyl
255 and 29|. At the same time, the duct 2,15 is
inder IIJ-3 either through the duct 292 or the duct 70 on exhaust through the ports 241, grooves 232,
293. Both of these ducts connect with a duct 282
and ports 245, while the duct 289 is on exhaust
through Jthe needle valve 3M (Fig. 19) duct 396,
which leads to the lower end of cylinder |93. The
ports 259 in the sleeve 22|, grooves23| in the
connection ‘betweenl the duct 282 and the duct
iustablv threaded mwa-Cep member 286 that is
The pressure fluid fiowing into the .duct '255
holds the piston |80 'to the left in the position
the grinding wheel into the Adressers in accord
ance with .the amount of stock which it is Vdesired
shown in Fig. 18, holding the end-dressing mech
to dress off the wheel inthe subsequent `dressing
anism in inoperative position. The pressure ñuid
ñowing through the duct 255 also `holds the >pis 5
During the described movements of the side
and end-dressing mechanisms into operative posi
ton 286, which controls the feed of the >grinding
tion and feed of the grinding wheel, the pistons
wheel, at the right end of the cylinder 285 with
the'pawl 21| in reset position. The pressure-fluid
|02 and |54, which roperate the side and end
dressers, respectively, remain at the upper ends
also 'flowing through the duct 255 into the ducts
256 and'l40 forces the ball-check valve v258 open 10 of their cylinders |03-and ¿|53 in the positions
shown in Fig.ï18, forthe line 28| remains on 'sup
against the resistance of the'spring 262, but closes
ply'andlthe line 280ïremains on exhaust.
`th'eball-check valve 259. Thus it flows into the
cylinder ll`2'6'th'roug'h the lduct 250 to hold the ïpis
`With the side and end dressers in operative po
ton |25 'at the right hand position shown in Fig.
sition,~the>operator rotates the valve’220- still fur
ther to the position vshown diagrammatically in
18, holding the side-dressing mechanism in 'inop
Fig. 16. This puts the lin'e 280 on supply through
erative position.
-In the described position of valve 220, the pis
the ports 248, grooves 230fandf233, ports 250, and
tons |02 and |54, which operate the side and end
ducts 305 «and -301 (Fig. ï1`9), while the line`28|
is put on exhaust ‘through the ports 239,-grooves
dressers, respectively, remain at 'the upper ends
oftheir cylinders |53 and |53, respectively,‘in 'the
231| and ports í2`5l. At the same time, the line
positions shown in Fig. 18, for the pressure fluid
215 remains on supply and the -line 255 on ex
flowing through the line 28| enters the lower end
haust, thus 'keeping the dressing mechanisms
of the cylinder |03 throughthe open ball-check
in their operative positions.
valve'281 and the ducts 283 and 284, while the
With the line 200 'on supply, -the pressure-fluid
shuttle valve 293 isheld in its lowermost position
flows into the upper end of the cylinder |03 forc
in the valve chamber 29| through flow of the pres
ing the vpiston »|02 downwardly in the cylinder
sure ñuid 'from the ducts 28| and 290 into the
|03 from the position shown in Fig. 18, causing
upper >end of the valve vchamber 29|. With the
the side dresser arms 92 and 95 to be'swung >in
valve 293 in its lowermost position, the pressure
one direction to rough-dress the outside and in
ñuid iiows from the duct 3|0, through the ports 30 side surfaces Aof the grinding wheel. At this
299 and v298 of sleeve 292 into the duct 3|'5 to
time, the lower-end of 'the cylinder |03 is on e'x
the-'lower end of the cylinder |53, while the upper
haust through the duct 284 and needle-valve 285.
end of this 'cylinder is on exhaust through the
With the line ¿28| on exhaust, the line 290 Ais
duct 3|8, throttle valve |51, duct SI5, ports 300
also on exhaust. Hence, the Yspring `294 ‘forces
and 30| of sleeve 292, and ducts '3|2 and 3|3.
35 the shuttle valve 293 upwardly in the valve cham
When the operator wishes to eîïect dressing
ber 28| vfrom the position shown in Fig. 18. Thus
of the grinding wheel, he rotates the valve 220
the line 3|'6 is put on supply from the line 3|`0
by ‘the Vhandle 223 to move the valve to the ñrst
through the -por'ts 299 and '300 of sleeve I292 (Fig.
position indicated diagrammatically in Fig. 15.
13), and the line 3|5 is put on exhaust through
This reverses the direction of ñow of the motive 40 the 'ports 298 and I'2910i sleeve i292, and lines 3||
fluid through the lines 255 ’and 215, while main
and 3| 3. Thus, the piston |54 is forced -down
taining the'previous direction of flow of the mo
wardly in `the cylinder |53, causing the end
tive fluid through the lines 28| and 280. Thus
dresser lto swing in one direction about the axis
the line 215 is put on supply through the ports
of its shaft I '41 -(Fig. 3) to effect rough-dressing
248, grooves 230 and 233, and ports 2131, while the
of the tip ‘of 'the' grinding wheel.
line 255 is put on exhaust through the’ports 248,
It will be noted that the rough-dressing move
grooves 232, and ports 2115.
ment of the end-dresser is unthrottled, and hence
With the line 215 on supply and the line 255
the end-dresser 'sweeps over the rounds and tip
on exhaust, the pressure-fluid forces the piston
of the wheel at the rapid rate induced vby full
|80 to the 'right in the cylinder |8| lfrom the 50 pressure of the >motive nuid -on the piston |54.
position 'shown in Fig. 18, the right 'han'd end
The rough-dressing movement of the side dress
of the cylinder |8| exhausting through the lines
ers may `be limited, however, by the setting of
251, 256 and 255. Thus, the end-dressing mech
the lthrottle valve 285. The relative rates of the
anism is swung into operative position 'through
rough-dressing movements of side and'end dress
the connection of the piston-rod |82 (Figs. 3 and 55 ers may, therefore, be adjusted as desired.
4) with the housing |52 which carries the-end
'The‘operator now reverses the direction of rota
dressing mechanism. With the line 215 on sup
tion of the valve 220, moving the valve back 'from
ply `and the line 255 on exhaust, the piston |25 is
the position shown diagrammatically in Fig. 16
also 'forced to the left in the cylinder |26 from
to that shown diagrammatically in Fig. 15. This
the position shown in Fig. 18, thus causing the 60 again places the line 28| on supply and the line
side-dressing mechanism to be swung also about
280 "on exhaust'while maintaining the lines 215
the hinge 5| (Figs. 7 and 8) into operative posi
and 255 on supply and exhaust, respectively.
tion through the connection of the piston-rod |35
With the line 28| on supply, the motive fluid
with the slide 4| (Fig. 9) which supports the
flows through the ball-check valve 281 and ducts
side-dressing mechanism. At this time 'the ex 65 282, 288, 283, and 284 to the lower end of the
haust fluid flows from the left-hand ‘end of the
cylinder |03 forcing the piston |02 upwardly in
cylinder |26 through the duct 290, the vnow-open
the cylinder to the position shown in Fig. 18,
ball-check valve 259, and the lines |40' and 256
causing the side dressers to be swung back across
into line 255.
the 'grinding wheel. During this return move
With the line 215 on supply and the line 255 70 ment, lthe motive ñuidexhausting from the up
per end of the cylinder |03 through the duct
on exhaust, the piston 268 is also actuated, be
ing shifted to the left from the position shown in
282 is Vthrottled by the throttle valve 3|4, for at
Fig, 18. This causes the pawl 21| to rotate the
this stage the ball-check valve 308 is closed by
ratchet'wheel 213 actuating the wheel-feed mech
operation of the spring 309 and by the pressure
anism of the grinding machine, thereby feeding 75 of the fexhaust iluid on the "ball, Thus,'the rate
of the return or finish-dressing movement of the
side dressers is controlled by the setting of the
throttle valve 3M.
With the line 28| on supply, the line 290 is put
on suuply also, causing the valve 293 to be forced
downwardly in the valve chamber 29|, putting
the line 3|5 again on supply from the line 3|0
and putting the line 3|6 again on exhaust
through the line 3|2. This causes the piston |54
to be forced upwardly in the cylinder |53 back
to the position shown in Fig. 18, causing the
end-dressing diamond U15 to be swung in its re~
turn or finish-dressing movement across the tip
of the grinding wheel. In this return movement,
the upper end of the cylinder |53 is on exhaust
through the duct 3|8 and the throttle valve 32|,
ation is much greater than the distance which the
end dresser has to cover. As a result, in prior
dressing mechanisms, the end dresser traveled
at a much slower rate around the tip of the wheel
than the rate of travel of the side dressers across
the side surfaces of the wheel. Consequently in
prior dressing mechanisms the end dresser dressed
a helical surface of much finer lead on the tip
surface of the wheel than the helical surfaces
dressed bythe side dressers on the side surfaces
of the wheel. The tip surfaces became, infact,
practically burnishing surfaces and this is what
caused burning of the bottoms and fillet portions
of the tooth spaces of gears when the sides and
bottoms of the tooth spaces were ground- simul
This defect has been overcome with the present
for the spring 3|1 and the pressure of the ex
invention by provision of means for independenth1
haust fluid close the ball-check valve 3|9. Thus,
adjusting the rates of movement of the side and
the rate of the return or finish-dressing move
ment of the end dresser may be controlled by the 20 end dressers. During rough-dressing, the exhaust
line 3 5 from the end dresser may be full open and
setting of the throttle valve 32|. It will be noted,
the end dresser may travel at top speed over the
therefore, that the throttle valves 3M and 32|
rounds and tip of the wheel. By properly adjust
permit of adjusting separately the rates of finish
ing the valve 285 (Fig. 18) , then, the rate of travel
dressing movements of the side and end dressers.
of the side dressers can be adjusted to rough
The operator now rotates the valve 220 back
dress outside and inside helical surfaces on the
on to the position shown in Fig. 14. This keeps
whe-el whose pitch or lead P is equal to or but
the lines 28| and 280 on exhaust and supply, re
slightly different from the pitch or lead P of the
spectively, holding the pistons |02 and |54 in
helical surfaces rough-dressed on the tip and
starting positions, but it puts the line 255 on sup
ply and the line 21-5 on exhaust. This causes the 30 rounds of the wheel.
The lead of the finished surfaces dressed on the
piston |80 to be moved back. to the left and the
sides of the wheel is controlled in the dressing
pistons |25 and 256 to be moved back to the right
mechanism illustrated, as already stated, by the
to the positions shown in Fig. 18. The piston |80
setting of the throttle valve 3M, and the lead of
is moved back to the left by flow ofthe pressure
ñuid from the line 255 through the ducts 256 and " the finished tip surface of the wheel is controlled
by the setting of the throttle valve 32 l. The shuttle
251, the motive fluid exhausting from the left
valve 293 makes the movement of the end dresser
hand end of cylinder |8| through the duct 215.
independent of the movement of the side dress
Thus, the end-dressing mechanism is swung to in
ers and. moreover, insures that sufñcient pressure
operative position about the axis of the stud 16|
is applied to the two pistons |02 and |54 to oper
(Fig. 4) through the connection between the pis
ate both in the time interval desired; the pressure
ton rod |82 and the housing |52. The piston |25
line 3|@ that leads to the shuttle valve 293 is in
is moved back to the right by flow of the pressure
dependent of and does not bleed the pressure line
iiuid from the line 255 through the lines 2-56 and
255i that leads to the control valve 220. By adjust
|40, the ball-check valve 253, and duct 260 into
the left hand end of the cylinder |26. Thus, the 45 ing the throttle valves 3 I4 and 32 I, then, a helical
surface can be dressed on the tip of the wheel
side-dressing mechanism is swung to inoperative
which is of approximately the same lead as the
position through the connection between the pis
helical surfaces dressed on the sides of the wheel.
ton rod |35 and the slide 4|, which carries the
side-dressing mechanism (Figs. 9, 7, 8, and 1).
This is illustrated diagrammatically in Fig. 21,
where it will be seen that the pitch P’ of the fin
At this time, the right hand end of the cylinder
ish-dressed tip surface of the wheel is equal to
|25 exhausts through the duct |4| and line 215.
the pitch P’ of the finish-dressed side surfaces
The piston 266 is moved back to the right by ilow
of the wheel. In Fig. 2l, 96'" denotes the posi
of the pressure-duid through the line 255, the
tion of the insidel dressing tool at the end of its
right-hand end of the cylinder 265 exhausting
through the lines 216 and 215. This causes the 55 return or iinishing stroke, while 93”' denotes the
position of the outside dressing tool at the end
pawl 21| to be reset with reference to the ratchet
of its return or finishing stroke, and |95'" de
feed mechanism.
notes the position of the tip-dressing tool at the
In the forward or rought-dressing strokes of
end of its return or ñnish stroke. In the iinish
the side and end dressers, the tip of the outside
dressing diamond moves in a plane 340 from a 60 ing strokes, these toois move from the positions
shown at 66", S3", and |95”, respectively, in
position such as denoted in dotted lines at 93’ in
Fig. 20 to the positions denoted at 96”', 93”', and
Fig. 20 to the position 93", while the inside
dressing diamond moves in a plane 34| from a
position such as denoted at 96’
this ñgure to
the position 96", and while the end-dressing
diamond moves in an arcuate path from a position
such as denoted at |95’ to the position |95”. Dur
|Q5'", respectively, in Fig. 21.
In the diagrammatic View of Fig. 21, it is as
sumed that the outside dresser is in Contact with
Vthe wheel during its return swinging movement.
This would be the case if there were a rigid or
non-slipping contact between the arm |05 (Figs.
ing the movements of the dressing diamonds, the
.l1 and 12) and the cam or disc |08 which controls
grinding wheel is, of course, rotating on its axis
70 the axial position of the shaft 90 that carries
at high speed.
the outside dresser. Where the arm |05 is con..
In prior types of dressing mechanisms, the
nected, however, to the control cam |08 through
three dressers were Connected to operate together
a lost Y'motion device, such as the ball |06 and
and to complete their operation together. As will
taper block | I1 shown in Fig. 11, then on reversal
Vbe seen, however, the distances which outside and
inside dressers have to cover in the dressing oper 75 of the motion of the shaft 90 at the end of the
forward or roughing stroke of the outside dresser,
are. required to position the dressers in correct
dressing relation to the wheel. Thus, the ring
member 35 (Figs. 1 and 2) is adjusted on sleeve
there will be a slippage of the ball en the cam
surface with the result that the shaft 90 will be
29 to position the side dressers at a point to min
imize possibility of interference of the side-dress
ing mechanism with the work during grinding,
wheel on the return or ñnishing stroke of the
and the plate 285 (Fig. 5) is adjusted on the ring
dresser. Hence. the outside surface ofthe wheel
member 35 to minimize possibility of interference
will not be dressed on the return stroke, but will
of the end-dressing mechanism with the work;
have the finish produced on the roughing or for
ward stroke only of the outside dresser. A wheel 10 the slide dl is adjusted rectilinearly on the ex
tension 5B (Fig. 8) of the ring member 35 in ac
so dressed is illustrated diagrammatically in Fig.
cordance with the principles of Wildhaber et al.
22 where 34Go denotes the plane of swing of the
Patent No. 2,311,302 above mentioned and de
tip of the outside dresser on its return stroke and
pending on whether substantially straight, con
93a denotes the position of the outside dresser at
the end of its return stroke. The inside dresser 15 vex, or concave profiles are desired on the sides
ofy theV grinding wheel; the plate 55 is adjusted
and tip dresser will perform the finish dressing
rectilinearly on the bracket 50 (Figs. 1 and 9)"in
operations on the inside and tip surfaces of the
accordance with the diameter of the grinding
wheel» as before. Thus, the inside and tip surfaces
wheel to be dressed; and the plate 65 is adjusted
of the wheel will be dressed to helices having
pitch P’ while- the outside surface will be left 20 rectilinearly on`the plate 55 in accordance with
the height of the wheel; the housing '.'5 is ad#
dressed to a helical surface having the pitch P.
justed angularly on the plate 55 in accordance
A A wheel such as shown in Fig. 22 can be used
with the pressure angles of the inside and out
to grind gears at much higher speeds without
side surfaces of the wheel. Thus, also, the
-fear of burning than can be done with any prior
bracket |95 is adjusted on the plate 255 (Fig. 5)
type wheel. Moreover, the gears will have sub
to position the end dresser in accordance with
stantially the same surface finish on both sides
the'height of the wheel; and the slide |68 is ad
and in the bottoms of the tooth spaces.
justed on the bracket |55 in accordance with the
If a circular disc, instead of a cam |10, is
diameter of the wheel. The throttle valve 285
mounted on the shaft |41 (Fig. 3) to engage the
follower Ill, then the only -movement that the 30 (Fig. 18) is adjusted to control the rate of move
ment of the side dressers relative to that of the
rend dresser has during dressing is a simple swing
end dresser during rough-dressing; and the
ing movement about the axis of the shaft |41,
throttle valves 3M and 32| (Figs. 19 and 18) are
and the end dresser will dress an arcuate tip
adjusted to control the relative rates of move
surface on the wheel as shown in Figs. 20 to 22
ment of the side and end dressers during finish
inclusive. By employing a suitable cam |16,
dressing. Cams |19', |58 and |29 (Figs. 3, 5, 11,
,howevery the end dresser can be rocked about the
12, and 2) of suitable configuration are selected
axis of the stud ISE (Fig. ‘1) during swing of the
in accordance with the shapes which it is desired
shaft |41 so as to dress a substantially fiat surface
to dress on the tip and sides of the wheel.
on the Wheel. This is illustrated diagrammati
Assuming that the necessary adjustments have
cally in Fig. 23. Here Sail and 343| again denote 40
been made, when the operato-r desires to dress
the planes of movement of the outside and inside
the wheel, he moves the control valve 229 from
dressers S3 and S6. During the ñrst part of the
the position shown in Fig. 14 to that shown in
swing of the end dresser from one side of the
Fig. 15 to put the line 215 on supply and the line
wheel to the other, a dwell portion of the cam
255 on exhaust and bring the side and end dress
VFD' is in contact with the rider, VH, and the
ers into operative position and advance the
movement of the dresser is effected solely by the
grinding wheel axially in accordance with Wear
rotationof the shaft |41 on its axis. Hence, the
of the wheel and the amount of stock to be re
dresser may move from the position |951 to |552
moved therefrom. Thus, the piston |88 swings
dressing around at the juncture of the tip sur
face 33 of. the wheel with the outside surface 3|. 50 the housing |52 (Figs. 3 and 4) about the pivot
stud |21, moving the end dresser into operative
Then the riseon the cam surface lli] comes into
relation with the grinding wheel; the piston |25
engagement with the rider VH and causes the
swings the bracket 5U (Figs. 7, 8 and 9) about the
whole end-dressing mechanism to be swung about
hinge pin 5| moving the side dressers into opera
the axis of the shaft |5| as the shaft Ili‘! con
tive relation with the grinding wheel; and the
tinues toA rotate. The swinging movement about
piston 266 (Fig. 13) rocks the arm 269 causing
the stud |G| causes the dresser to dress a substan
the pawl 21| and ratchet wheel 213 to actuate
tially fiat surface on the tip of the wheel. In this
the wheel-feed mechanism.
movement, the diamond travels from position
Then the operator moves the control valve 220
|952 to |953. Then the rider Il! again rides on
(Fig. 18) on further to the position shown in Fig.
a dwell portion of the cam |15 and the movement
16‘to put the line ‘Z853 on supply and the line 28|
Aof the diamond is again controlled wholly by the
on‘exhaust. This forces the piston |22 down
swing of the shaft IM. Hence, as the dresser
wardly to rock the side-dresser arms 92 and 95
moves from position I 953 to position |954, it
axially displace rearwardly and the outside
will clear the outside surface of the
dresses a round at the juncture of the inside sur
face 32 of the wheel with the tip surface 33
thereof. Of course, in the movements of the’
dressers they turn up helices on the surfaces be
ing dressed, as already described, but these helices
(Figs. l and 2) about the axes of shafts 90 and
5 l; respectively, causing the side dressers to rough
dress the outside and inside surfaces of the wheel;
and it permits the spring 29.4 to shift the shuttle
'valve 233, putting the line :HGV on supply and the
have been omitted in Fig. 23 for the purpose of
line 315 on exhaust, causing the piston |54 to
clearness in illustration.
70 swing the arm |66 (Figs. 3 and 4) and move the
The, operation of the dressing mechanism of
end dresser over the tip of the wheel from one
side thereof to the other to rough-dress the tip
the present invention, as illustrated, will be un
derstood from the preceding description but may
of the wheel and the rounds joining the tip with
be summed up hereV briefly. First of all, of
the sides of the wheel. During the described
course, the various adjustments are made that 75 rough-dressing movement of piston IU?, the rate
Без категории
Размер файла
2 896 Кб
Пожаловаться на содержимое документа