вход по аккаунту


Патент USA US2404231

код для вставки
Äuäy E5, 1946.-
. 2,404,231
Filed Aug. 26, 1943
2 sheets-shea 1
' July l5, 1946@
i ¿__ E. HARPER
Filed Aug. 2e, 1945
à-sheets-_sheet 2
Ü .
Patented July 16, 1946
Lyndus E. Harper, Kansas City, Mo., assignor to
Omega Machine Company, Kansas City, Mo., a
corporation of Missouri
Application ‘August 26, 1943, Serial No. 500,082
- 5 Claims.
My invention relates to variable speed drives,
and more particularly to a variable speed trans
mission that is adjustable so as to have any de»
to this large area of contact between the'follower
and cam, it is proposed to mold the cam4 members
sired output speed between a >'predetermined
minimum and maximum.
area of contact with the cam.' Furthermoraî'due
of plastic material, 'which makes it possibleto re
duce the friction between the cam 'and follower?
My invention is particularly adapted for use as
a speed reduction .device in which the output
speed is variable or adjustable between any de
considerably below that whichwould otherwise
The above referred to advantagesxof my invene
sired predetermined minimum` and maximum,
tion exist because of the particular
beingparticularly adapted for use as a variable 10
speed reduction device in which the driven shaft
prising a member having sliding contact -with
or 4output shaft is'` adapted to be operated at a
the surface of the cam, which may be "referred
very slow rate of speed relative to the driving
shaft, and yet at the same time the speed be ad
to as a shoe"carried by the follower, and which
justable to obtain very slight differences in speed 15 has a universally tiltablemc‘iunting- on: the fol.-`
lower so as to adjust itself properly in substantial
of the output or driven shaft, in spite of 'thel fact
with the surface of theïcam member
that the same is operating at a very slow speed in
for any adjusted position thereof 'axially ralong
any adjustment of said speed reduction device.
the length of the cam.
' ' "
More particularly my’invention comprises a
variable speed drive or transmission means com
prising- cam and follower members, saidv cam
20 tion as a speed reducing devicey
that, by using>
my invention, the speed of the driven- shaft canU
members being of such a ' character that the
throw of the cam varies so as to increase grad~
be varied to any desired‘extent andthe >move-l
ment> v thereof can be accurately controlled, so
ually from one end of said cam to the other end
thereof in an axial direction, the cam and fol 25 that it will start and stop with‘the starting and
stopping of the driving shaft, if this is desired,
lower membersI being relatively adjustable so as
this being accomplished by the worm gear drivá
to get any 'desired position of the follower on the
ing means provided between the driving shaft and
cam to get the desired Oscillating movement of
the variable speed means, and between‘the >vari
the follower, to produce any desired amplitude of
movement of the follower when acted upon by 30 able speed means and the driven shaft,thus pre-venting any over coasting of the drivenshaft;
the cam within the limits of the throw of the cam
Other objects and advantages of my invention
from the position thereof of least throw to that
will appear as the description> of the drawings
of greatest throw. The cam members are, pref
proceeds. I desire to have it understood, however,
erably, so made that the same taper or gradual
I do not intend to limit myself to the par
increase in height from the one end thereof to
ticular details 'shown or described, except vas ,dei
the other end thereof to provide a cam portion
fined in the claims.
at the one end of said cam that produces no
In the drawings:
y I
movement or oscillation Vof the follower and one
of the maximum amplitude desired at the other
able speed transmission applied to aspeed ref
end thereof, the surface of the cam gradually 40 duction
device preventing over coasting._ ` rising from said one end of the cam to the other
Fig. 2 is a_ section taken substantially on the
end thereof, so that the cam surface thereof is
line 2_2 of Fig. 1, certain parts being _shown in
substantially of a conical character. '
It is a particular purpose of my invention to
provide, in a device of the above mentioned char
Fig. 3 >is a fragmentary detail sectional'view of
acter, cam and follower means of such a charac
the cam contactingshoe and associated parts,
ter that the follower will cooperate with the cam
to obtain the desired speed changing action of
the device even though the cam surface is not
1 on
a slightlyinenlarged
detail to
the drawings, "my ' im@
Fig. 4 is a section taken on. the line 4_4 of Fig.
machined, the character of the follower being 50
provedV variable speed >transmission is shown .in
Fig. 1 as being applied to a speed reduction-»de
not necessary, the only finishing that is necessary
vice, which is mounted in a frame or housing* 5,
being to remove the roughness from the surface
A drive shaft 6 is mounted in suitable‘bearings
of the cam members by sanding the same. This
is due to the fact that the follower has a’large 55 in said housing and is provided ’with‘a'worm‘ l
mounted thereon so as to >rotate therewith. Said
such that machining or grinding‘of the cam is
, 2,404,231
Íworm meshes with a worm wheel 8,'which isñxed
on the cam shaft 9, which is mounted in suitable
bearings in said'housing or frame 5.
hold the shaft I9 in adjusted position. Connected with the shaft i9 externally of the hous
ing 5 is an indicating device 3I, which may be
in the form of an ordinary revolution counter,
3 on said cam shaft 9 are the cam members I0 and
but which will indicate the Vposition of the cams,
l I I. ' Said cam members are mounted on said shaft
as the same can be calibrated to indicate the po
sition of the cams, or to indicate the speed of the
output shaft for such position of Vthe cams, or
‘so as to rotate therewith'but are longitudinally
slidable thereon, the _particularfdriving connec
i tion betweenthe shaft and the cams being of a
any other result produced by the rate of rotation
p well known character and not being shown 'inv
; detail in the drawings. Said cam members Il)
of said shaft. , Said shaft is further provided with
stop members in the form of pairs of nuts: 32 lo
il and
a deñnite
shaft and
to each 1 . cated on vopposite sides of the sleeve-like meme
' ber 23, the >same Vnot being shown in any opera
1 tially Vof the shaft. Thus, if the shaft 9 rotates
Ä in a'counter-clockwise direction, as shown in
'tive position in Fig. '2, but spaced fromY the other
parts so as to clearly show the same. The adjust
ment of the nuts :32 would, of course, be such as »
à 2, the rising portionfl2 of the cam lil willbe' in
‘ suchra position relative to the receding portion I3
to limit the movement of the sleeve-like member
l of the cam II, that the followerengaging thecam ,
23 responsive to rotation of the crank 21 between
desired limits, the extreme rof which would be
§ II will vreach the rising portion I!! of theY cam I_ _l f g,
" beforethe followerengaging the cam IB leaves
the axial length of the cam portions Il) and I I. '
~ the rising portion I2 thereof and passes to the re
- i cedingV portion I5'thereof. Thisrwill be obvious.
, i upon reference toFig. 2.
will be explained below..
Cooperating with the cam members I0 and I!
Vare follower members 33 and 34, the follower
The purpose of .this
' member 33 Vengaging the camIû and the follower
Said follower members
' l
34 the cam II.
While various'means may be provided for hold- ‘ rmember
are substantially the same in construction, each
1 .ing the cam members in their lrelative .axial Vand 25 having an arm 35 extending from a hub-like body
ï circumferential position, preferably;` .the same
are made integral, a connecting portion I5 be- .
~ ing providedjoining the cam I0 to the cam II.
As willrbe obvious from Fig. l, each of. the i.
portion" 36, said hub-like body portions being len_ »
gaged by collars 31 secured to the shaftf3ßfto Vpo-V
sition the same> on the Shaft. ,Each of said'fole
lowers is provided with a one-way roller clutch
cams increases
in height or throw Yfrom Vthe small f30
device 39, by means of which each'of the same
end I1 thereof Vto the large endY IBthereof, the ‘
are connected withV the shaft, and a spacing
cam'surface being. substantially a conical surface
washer 40 is provided between said clutch de
fps@ that if a follower member is adjusted magm
Wise or »axially relativeto the cam, so asl to en-`
vices 39. :
end I1 ofthe cam to the large end .I8'thereof~ c
so as to provide a chamber of varying depth be
tween said members 4I and 42 confining fthe
while any desired type of'eclu'tch thatis sub-'1 -.
Vgage any desired portion along the length of the 35 stantially instantaneousin operation can be »pro- Y
cam .(by the length of the camv being meant'the
vided, preferably, aV roller clutch of the typeV
extent Vin ak direction axially of the shaft-9) ,‘ the
shown in Fig. 4 is provided, the same comprising
throw or amplitude of movement of the follower
a polygonal member y4I keyed to the shaft 38, and
` îme'mber due to engagement with the cam will
an outer memberV 42 Vof a cylindrical character
gradually increase as the position 'of the fol
having an inner cylindrical surface 43 _spaced
lower relative Vto the cam is varied from the small
from Vthe polygonal periphery .of the member 4l
In practice,gin,the particular form of the inven
tion shown, the cams are actually " adjusted
rollers 44,'the member 4I being, preferably, pro-V
lengthwise of the shaft 3,’ instead of the fol V45 vided with springs 45 for urging the rollers to-v
lowers being adjusted, the followers having .such
ward one end of each of the flat faces 45 of the
a >relative >position to each other that thetwo' »
polygonal member 4I.
followers will engage corresponding portions
It will be obvious hat as the arm 35 is moved
axially of the cams for anyadjustment of the
cam members.
, -
The adjusting means comprises a screw-thread;
ed ’rotatable shaft-like member I9 mounted in
50 in aY counter-clockwise direction in Fig; v‘l rela
tive to the shaft 38 by means ofthe cam IQ or
suitable Ybearings in the frame 5,- but held against Y
II, as the case may be, the rollers 44 will have'
a tendencyfto roll or slide on the flat facesk 45
and be crowded between the narrowing passage ~
axial movement relative to the frame by means
formed betweenthe cylindrical surface V43 `and
of suitable stop members, such as the collars 2B 55Y the plane surface 45, torthus gripY the polygonal .
and.2l. Said shaft-like member I9 is'provided
member 4I and cause' said member'4I to bero
with a screw-threaded portion 2-2 with which a
tated with the member 42. As the springs 45 will
screw-threaded sleeve-like member 23 engages,
hold the rollers 44 in a position closely adjacent
said screw-threaded sleeve-like member 23 act-v ’that in which the same will »act as gripping.
ing in a similar manner to a nut on said shaft, 60 means between the Vmembers, 42 and di, this
and having a laterally extending arm 24 .thereon
mounted ink an annular groove between the
‘ -ñanges 25 on‘a rearward extension 25 ori-,the cam
clutch action will be substantially instantaneous.
However, when the arm 35moves in the’opposite
direction the tendency for the members 44 will
member I0. It Ywill be obvious that' if then shaft
be to move in the opposite direction against the
I9is rotated by means of the crank 21 the nut. (55 tension of the springs 45, slightly compressing
like member 23 will be either moved to the right
said springs, but freeing the rollers 44 Yand dis-V
or leftgas viewed in'Fig. 1, dependent Y'upon the
direction of rotation 0f the'crank .member 2l,
thus moving the cam system -made up of the cams..
IIJ andïl I Ycorrespondingly to the'right or left. '
VThe shaft I9is also provided with a collar 23',
with which a coilspring 29 engages, said springV '
‘ being mounted betweenvsaid collar and a-.boss
engaging said members 42y and 4I fromeaehother
so that theclutch device will operate in only one
direction to always rotate the'shaft 3B
same direction. As theV rising portions I2 and I4 ,
of the cams I0 and II overlap,circumferentially
of lthe same, it will be obvious-'that when. one.
follower is being swung 1n a'direction to cause . Y .
30 >projecting inwardly from the frame 5‘, ‘and
the arm 35 thereof to actuate the one-way clutch Y
beingV under.: compression soV asv toffrictionall-y v1.5
device 39 vassociated Awith that arm,gthe'other
follower‘will be moving in the opposite direction
free ofthe shaft 38"-until the rising portion of its
camfis reachedL'whereuponit'will also begin to
rotate the sh'aft through its one-way clutch
. the small ends I1 of the ‘cam members IU >and Il
upon' adjustment bylmeans ofV the crank 21. ’
* It will further be seen that due to the provi
sion of the worxndrive made up of the worm
member 51 vand the Vworm wheel 58, the Shaftï59
member 39, so as to give `a >continuous‘rotation
constituting the output shaft of the variable speed
to the shaft 38 in one direction.
transmission and variable speed,` reducer [device
YVEach ofthe arms '35 isprovided with an en
largement 41 atV the extremity‘fthereof, through
will be'rotatedVV at a still'muchï lower 'speedï-than
the‘shaft- 3S. -ï‘f’Iï-hus- there lwill be »an -initialhspeed
which 'a bolt-lilàe-member 48 extends; which; is 10 reduction that is constant, due to the worm drive
provided with a spherical head 49 andï with an
made upl ofthe members 1¿ and 8,"a variable's'peed
annular shoulder'50` engaging the enlargement
reduction'obtained by them'embers-` I n and 'l -I and
41 to clamp said member 48 in position when the
the followers cooperating therewith, and another
nut 5| is tightened down on said member 48.
ñxed speed reduction due to the provision of the
The ball end or head 49 of the member 48 con 15 worm 51 and worm wheel 58. As a result, the
stitutes the ball member of a ball and socket
shaft 59 can be'operated at a very accurate ad
joint, providing a universally tiltable connection
justed speed, although its rate of rotation will be
extremely slow as compared with the drive shaft
52, which has a socket portion 53 receiving the
9, which makes possible very close adjustment of
ball head 49. Said shoe member 52 is provided 20 slowly operating apparatus, which must be accu
with an annular enlargement 54 presenting a
rately controlled. Also, due to the provision of
substantially flat face 55 of large area to the
the worm drives, any over-coasting of the driven
surface 56 of a cam, such as the cam l l, of which
apparatus operated by means of the shaft 59 is
a fragment is shown in Fig. 3. While the flat
entirely prevented, and it will start and stop si
face 55 has substantially line Contact with the 25 multaneously with the starting and stopping of
curved surface 55 of the cam Il, and similarly
the drive shaft 6.
with the cam t0, lengthwise or axially of the shaft
What I claim is:
9, said shoe 52 has Contact over a considerable
l. A variable speed transmission comprising a
distance with the conical surface of the cam, and
cam shaft, means for rotating said cam shaft, a
as a result, any slight variations in the surface
longitudinally tapering» cam thereon gradually
of the cam due to molding or casting thereof, will
varying in throw axially of said shaft, a follower,
between said arm and a head or shoe member
have no effect on the operation’of theV cam in
oscillating the arm 35 by which the shoe or con
said follower is mounted, said follower comprising
tact member 52 is carried.
In view of the provision of this sliding shoe
member engaging the cam Il andthe cam Hl,
an arm mounted to swing about the axis of said
follower shaft, and a cam engaging member
mounted to swing universally on said arm and
it is unnecessary to highly i'lnish the cam sur
faces, only a rough finishing operation being nec
and a shaft parallel to said cam shaft on which
slidably engaging the convexly curved surface of
said cam with a line contact.
essary on the surfaces of the cams, if the same
>2. A variable speed transmission comprising a
are cast of metal, and no finishing thereof being 40 cam shaft, means for rotating said cam shaft, a
necessary if the cams are molded of plastic mate
.longitudinally tapering cam thereon gradually
varying in throw axially of said shaft, a follower,
The shaft 38 is mounted in suitable bearings in
and a shaft parallel to said cam shaft on which
the frame member 5 and has a worm 51 fixed
said follower is mounted, means for relatively
thereto to rotate therewith, which meshes with a
radjusting said cam and follower axially of said
worm wheel 58 fixed on the shaft 59 to rotate
cam, said follower comprising an arm mounted
therewith, said shaft 53 constituting the output
or driven shaft of the device, the same being
mounted in suitable bearings in the frame or
to swing about the axis of said follower shaft,
and a cam engaging member mounted to tilt
universally on said arm and having a wide flat
50 face slidably engaging the convexly curved sur
Each of the follower members 33 and 34 are
face of said cam with a line contact.
provided with a rearwardly extending arm or
‘3. A variable speed transmission comprising a
finger Gil on the body portion 36 thereof, which
cam shaft, means for rotating said cam shaft, a
has a depending lug El receiving the compression
longitudinally tapering cam having a convexly
housing 5.
coil spring 62, which is mounted in a suitable
socket 63 in the bottom of the housing member
5, said spring 52 holding the shoe 52 of its fol-y
lower member in engagement with the cam with
which the same cooperates.
, curved cam surface thereon gradually varying in
throw axially of said shaft, a follower, and a shaft
parallel to said cam shaft on which said follower
is mounted, said follower comprising an arm
mounted to swing about the axis of said follower
It will be obvious that the shaft 9 is driven at 60 shaft, and a shoe universally tiltably mounted on
a reduced speed by the drive shaft 6 to rotate
said arm and having a fiat face slidably engag
the cams I9 and H, the cams l0 and Il oscillat
ing said convexly curved face of said cam with a
ing the arms 35 'of the follower members 33 and
line contact.
S4 through arcs dependent upon the adjustment
4. A variable speed transmission comprising a
of said cam members l0 and I I relative to said
cam shaft, means for. rotating said camshaft,
follower members. It will also be obvious that
a longitudinally tapering cam having a convexly
the arms 35 in their oscillating movements >will
curved cam surface thereon gradually varying in
operate the one-way clutch members to rotate
throw axially of said shaft, a follower, and a shaft
the shaft 33, and that said shaft 38 will be roe
parallel to said cam shaft on which said follower
v tated continuously, with an arrangement of cams
is mounted, means for relatively adjusting said
such as described., the rate of rotation'of the shaft
cam and follower axially of said cam, said fol
38 relative to the rate of rotationI of the shaft 9
lower comprising an arm mounted to swing about
being dependent upon which part of the cam
Vthe axis Vof said follower shaft, a member fixed
members IIJ and4 Il the followers engage, the
same approaching Zero as the followers approach
on said arm and depending therefrom, said mem- .
ber and said arm extending perpendicularlyto
2,404,231 '
comprising a hub rotatable about theaxis ofi said
` said shafts and at an angle to each other, anda
follower shaft,'an arm rigid therewith, a iinger on
n shoe universally tiltably mounted on said member
said hub, a ball ended member mounted on said Y
‘ and having a flat face slidably engaging said oon
arm, said ball ended member and said arm ex
vexly curved face of said cam with a line contact.
Y tending perpendioularly to said shafts and at an
' 5. A variable speed transmission comprising a
angle to each other,` a shoe universally tiltably
cam shaft, means for rotating said cam shaft, a l
mounted on the ball end of said member havingV
l longitudinally tapering cam having a convexly
â curved cam surface thereon gradually Varying in
throw axially of said shaft, a follower, and ashaft l
a flat face slidably engaging said convexly curved
face of said cam, andresilíent means engaging
said linger to hold vsaid flat face in line contact Í Y
parallel to said cam shaft on whichesaid follower
Y ,
‘ is mounted, means for relatively «adjusting said im with said cam.
Q ' cam andY follower Vaxially of said cam, said'follower
Без категории
Размер файла
752 Кб
Пожаловаться на содержимое документа