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Патент USA US2120842

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June 14, 1938.
“
<;_ A, RICH
2,120,842
FEED MECHANISM FOR SCREW AND SIMILAR MACHINES
Filed Aug. 21,’ 1936
2 Sheets-Sheet 1
Fig.1
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June 14, 1938.
2,120,842
C.'A. RICH
FEED MECHANISM FOR SCREW AND SIMILAR MACHINES
Filed Aug. 21, ‘1936
Fig. 5
Witness
Mi??m
2 Sheets-‘Sheet 2
Fly 6
Invgzior
@9
2,120,842
Patented June 14, 1938
UNITED STATES
PATENT OFFICE
2,120,842
FEED‘ MECHANISM FOR SCREW AND
SIMILAR MACHINES‘
‘Charles A. Rich, Providence, R. 1., assignor to
Brown and SharpeManuf-acturing Company, a
corporation of Rhode Island
Application August 21, 1936, Serial No. 97,183
(C1. 29-62)
14 - Claims.
The present invention relatesto improvements the line 3-3 of Fig. 1, to illustrate particularly
in feed mechanism for screw and similar ma
chines for fashioning articles successively from
bar stock.
,
In machines of this general description, the
Work is fed through a rotary feed tube preferably
provided at its forward end with feed ?ngers
which are arranged to frictionally engage with
and feed the Work into position against a stop
10 which operates to position the work for .the op
eration of the forming and cutting-off tools.
Positively operating connections are usually pro
vided for imparting to the feed tube a recipro
catory feeding and return stroke which is ad
15 justed in accordance with the requirements of
the work, so that it is always a little longer than
that required to insure the advance of the feed
ing bar by the frictionally engaging feed ?ngers
into operating position against the feed stop.
20 With this construction and arrangement of the
feed mechanism, it has been found necessary to
chamfer the rear end of each piece of stock
to prevent the engagement of the feed ?nger be~
hind the waste end of the bar after the comple
tion of the last article therefrom, with consequent
25 injury to the machine as the positive advance
of the. feed tube brings the waste end into en
gagement with the stock stop.
It is a principal object of the present invention
to provide a yielding connection in the feed mech—
30 anism above described, which will operate as a
safety cushion against excessive resistanceto the
advance of the feed tube, while at the same time
retaining the advantages of an accurately deter
, mined feed stroke of the feed tube under normal
03 U
operating conditions.
,.
..
More broadly stated, it is also an object of the
invention , to provide-a feed mechanism for a
screw or similar machine having certain elements
the feed slide and associated parts for actuating
the feed tube; Fig. ll is a sectional view taken on
the line 4—4 of Fig. 3; Fig. 5 is a sectional plan
view taken on the line 5-5 of Fig. 3; and Fig. 6
is a detail plan View of the latch.
The automatic screw machine disclosed in the
drawings as embodying in a preferred form the
several features of the present invention, com
prises a base In, turret tool support l2, turret 10
slide l4, stock stop It and a spindle assembly
for rotating and. feeding the work to the operat
ing tools including a feed tube "3 provided at its
forward end with feed fingers 20 and a chuck
mechanism generally indicated at 22 for posi
tively gripping and rotating the work.
The spindle assembly including the feed tube
i8 and chuck 22 is continuously rotated at a high
rate of speed from either of two oppositely driven
driving pulleys 24 or 26 through a clutch mecha .20
nism generally indicated at 21. The machine is
alsopprovided with a main driving pulley 28, amain
clutch 30 and drive shaft 32, as generally indicated
in Fig. 1, which is connected to drive the several op
erating mechanisms of the machine including the :25
turret l2, slide l4, the stock stop E6, the chuck
22 andthe stock feeding mechanism.
The con
nections through which these mechanisms are
driven from the clutch 30, and shaft 32 are well
known .in the art, and will be described only so
far as necessary to show the connection of the
present invention therewith.
The stock stop I6 is moved downwardly into
operating position to engage with and position
the leading end of the feeding bar, and is there
after‘ retracted during the subsequent ‘forming '
and cutting-off operations, through connections
which include a rock shaft 34 to which the stock
stop I6 is secured, a pinion 36 on the shaft 34, a
of novel construction and mode of operation, to
rack bar 38 engaging therewith and connected 40
bar into operating position, and having embodied
therein a safety cushion to prevent possible injury
to the machine through interference with the
a stationary pivot 42 and provided intermediate
its length with a cam roll 44 which rides against
the periphery of an actuating cam 46 on the cam
shaft 48 of the machine. A spring-pressed
plunger 50 slidably supported in a bracket 52 in
the machine base, engages against the under side
of the cam lever 40 to maintain the roll 44 in
operative engagement with the cam 46.
4 O provide for the accurate and-certain feed of the
I, feed stroke-of the feed tube and bar engaging
mechanism associated therewith. ~
,
With these and other objects in view, as may
hereinafter appear, the several features of the
invention consist in the devices, combinations
and arrangement of parts hereinafter described
and claimed, which together with the advantages
to be obtained thereby will be readily understood
at its lower end to a cam lever 48, supported on
For advancing thesuccessive portions of the
work into operating position against the stock
stop, a feed mechanism is provided which oper
50’
by one skilled in the artfrom the following de
ates to advance and retract the feed tube IS in
scription takenin connection with theaccom
timed relation to the operation of the operating
tools, the stock stop l6 and chuck 22. This 55
mechanism includes a feed slide 56 having guid
ing surfaces 58 which engage with a correspond
panying drawings, in which Fig. 1 is a view in
rear elevation of an automatic screw machine";
Fig; 2 is a somewhat fragmentary sectional View
vtaken on the line 2-—2 of Fig. 1, to illustrate par
ticularly the stock stop‘ and mechanism for actu
ating the same; Fig. 3 is an end View taken on
ing guideway carried on an extension 59 of the
machine frame.
The operationrof the feed slide is controlled
2
2,120,842
from a feed lever 68 supported intermediate its
length on a, stationary pivot 82 and provided at
84 has formed thereon a peripheral step 98 which
per end of the feed lever 68 is grooved to re
ceive a sliding block 68 pivotally mounted on a
thereto.
serves as a support for the latch 88, and also
its lower end with a cam roll which rides in a
provides a shoulder for engagement with the ad
spiral cam groove 84 formed in the face of a
jacent face of the feed slide 56 to limit the for
cam cylinder 66 on the cam shaft 48. The up-5 ' ward movement of the members with relation
slide which is in turn adjustably supported in
A shoulder 92 formed adjacent to the
step 98 on each of the members 82 and 84 is
‘arranged for engagement with adjacent side por
a sloping guideway 18 formed on the feed slide ' 'tions of the latch 88, so that any movement of
58. The position of the block 58 and slide sup
the latch and. feed tube l8 rearwardly or to the 10
port therefor in the guideway 78 is adjustably
left of the feed slide 56, as shown in‘ Fig. 4,
determined to vary the length of the feeding and
return stroke of the feed slide by means of a
must carry with it the slidable supporting mem
bers 82 and 84. For convenience of assembly,
the latch 88 is pivotally mounted on the step
98 of the supporting member 82, and is provided
screw 12 threaded into the slide and supported
15 at its upper end against axial movement in a
bearing l4 carried on the upper end of the guide
way 18.
r
.
The feeding mechanism as thus far described,
comprising the constant throw feed lever 68 and
the adjustable connection with the feed slide 58,
is- substantially identical with mechanism well
known in the art, and is arranged to impart a
positive advancing and retracting movement of
the feed slide 58 which is always slightly in ex
25 cess of that required to advance the leading end
of the feeding bar, frictionally engaged by the
?ngers 28, into operating position against the
stop
l6.
-
The present machine is provided with the
30 usual mechanism for actuating the chuck 22 to
engage with and rotate the work during the
operation of the forming and cutting-off tools.
This mechanism includes the chuck actuating le
vers ‘I5 fulcrumed in a ring 18 and controlled by
35 a sleeve member ‘I? and cam lever 18 which is
at its other end with a semi-circular slot 93
which is arranged to ?t tightly over the periph
eral step 98 of the member 84 between the sh0u1~
der 92 and the adjacent face of the feed slide
56. With this constructionand arrangement of
the parts, it will readily be seen that the move
ment of the latch 88 downwardly to the full line
position shown in Fig. 3, operates to move the
cover portion 86 thereofinto locking engage
ment with thebearing 88, and at the same time 25
to position the slotted portion 93 thereof in en
gagement with the step 98 of the member 84, so
that the members 82 and 84, latch 88 and feed
tube I8 are connected-to move as a single oper
ating unit. To assist in locking the parts in op so
erating position, there is formed in the feed slide
56, a segmental supporting surface 95 for. the
bearing 88 which extends slightly more than
half way around the periphery of the bearing,
and serves to prevent the bearing 88 and feed
as
tube I8 from moving out of position independ
nism from a cam on the cylinder 88. . Inasmuch
ently of the latch.
as this mechanism is well known in the art, and 7
The assembly including the slidable members
does not form directly any part ofthe. present 82 and 84, the latch 88and feed tube l8 are
actuated in timed relation to the feed mecha
40 invention, no further description or illustration
thereof is believed necessary.
I
.»
.
With the usual construction of the feed mech
anism above described, in which the feed tube
is positively connected for -movement through a
45 predetermined stroke, it has been found that any
excessive resistance or obstructionto the advance
of the feed tube is likely to result in serious dam
respectively onthe slidable members 82 and 84. 45
The spring connection acting upon the member
84 is fully illustrated in Fig. 5. A compression
spring 94 housed within the member 84, en
advance of the feed tube is likely to occur, for
gages at one end against a shoulder 96 of the
member 84, and at its other end against a col 50
lar 98 of .a pin I88 which extends through the
coils of, the spring, and is connected- at its right
hand or forward end to the feed slide 58. ,For
behind the waste end of a feeding bar, and are
therefore prevented from slipping with relation
thereto as the waste end is advanced against the
stop
l6.
>7
~
'7'
>
‘I
.
In accordance'with'the present invention, a
yieldable driving connection is provided between
the feed slide 56 and feed'tube- l8 which is ar
ranged normally to providea stationary relation
ship between these elements, but is capable of
yielding against excessive resistance to the ad
65
dot-and-dash position of the latch 88 in Fig. 5,
by means of identical spring connections acting
age'to the machine. ~ Such an obstruction to‘ the
instance, where the fingers 28 become caught
55
normally maintained in a fully advanced posi
tion to the right with relation to the feed slide
56 as shown in Fig. 4 and as indicated by the
vance of the feed tube, and thereby’ prevent pos~
sible injury to the machine. This connection, as
best shown in Figs. 3 to 6 inclusive, comprises a
latch 88 which is carried on two supporting mem
bers 82 and 84 on the feed slide 56, and is pro
vided intermediate its length with a ?anged cover
portion 88 ‘which is arranged for locking en
gagement with a ball bearing 88 carried on the
feed tube I8 and supported against‘ axial move
ment with relation thereto between two collars
83 and_85.
The members 1823and 84 take the
form of cylindrical tubes which are slidably sup
ported respectively in bores 81 and 89 formed in
the feed slide 56. Each of the members 82 and
clarity of illustration, the parts of the‘ spring
connection for the member 82, being exact du 55
plicates of the spring connection for the mem
ber 84, have been given the same reference char
acters so far as they appearin Figs. 3 and 5
ofthe drawings. It will be noted that the two
spring-pressed units including members 82 and 60
84 are located .on the feed slide 58 on opposite
sides of the feed tube I8, so that a balanced con
dition is obtained, in which an equal pressure is
exerted .by each of the spring-pressed members
82 and 84 to maintain the latch 88 and feed tube 85
I8 in a relatively advanced position on the feed
slide 56.
l
The springs 94 of the illustratedconstruction
are of sui‘?cient strength to maintain the mem
bers 82 and 84 and feed tube l8 connected there 70
to under'normal operating conditions of the ma
chine at all times in their fully advanced position
with relation to the feed slide 56, so that a nor
mally stationary ‘connection is provided between
the feed slide and feed tube, thus retaining the 75
3
2,120,842
advantages. of‘ the usual construction in which
a positively operating feed mechanism is em
ployed having no lost motion or play in the
parts to secure an accurate feed of the work.
The full line position illustrated in Fig. 5, shows
a relative position of the feed tube I8, latch 80
and members 82 and 8.4 with relation to the
feed slide 56 which is obtained when the advance
of the feed tube is obstructed as for example by
the engagement of the feed ?ngers behind the
waste end of an old bar which is fed against
the stock stop I6. Under these conditions the
yield provided by the springs 94 will permit the
feed tube and associated parts to move rear
15 wardly away from the feed slide 56, thus pre
venting any possible injury to the parts of the
feed mechanism.
With the construction as thus far described,
it will readily be seen that the extent of the
20 relative movement which may take place be
tween the feed tube I8 and feed slide 56 is
limited by the capacity of the springs 94, and
that once the springs have been fully compressed,
the feed tube will be again positively advanced
with the feed mechanism.
While the relative
movement thus provided for is amply-sumcient
to allow the feed slide to continue to the for
ward limit of its feeding stroke in the usual
case in which the feed tube I8 and ?ngers are
blocked from further movement behind the waste
end of a feeding bar, it has been found desir
able to make a further provision for an extreme
case in which the feed tube I8 might become
jammed at a relatively early stage in its forward
movement. In order to prevent possible serious
damage to the machine in the extreme case
above supposed, shear pins are provided in the
feed connections which will be sheared off by
the imposition of an excessively heavy load on
40 the feed connections to wholly disconnect the
feed tube from its driving mechanism. To this
end the pins I00 are connected to the feed slide
56 by means of shear pins I02 which extend
through the pins I00 and engage at each side
45 thereof against disks I04 recessed respectively
into the ends of the bores 81 and 89 in the
feed slide 56. The shearing off of the pins I02
operates to wholly disconnect the feed tube I8,
latch 80 and members 82 and 84 from the feed
50 slide 56 which can continue its movement in
dependently of these parts to the limit of its
feeding stroke.
In order to prevent the springs 94 and pins
I 00 from ?ying out of the machine when released
by the shearing off of the pins Hi2, each of the
members 82 and 84 have heavy metal caps in
dicated respectively at Hi6 and I08 screw
’threaded into the rear ends thereof.
It will be understood that the invention is
60 not limited to the speci?c embodiment shown,
and that various deviations may be made there
from without departing from the spirit and scope
of the appended claims.
What is claimed is:—
,1. In a feed mechanism for a screw machine,
the combination with a stop against which the
work is fed, of a feed tube having means for
frictionally engaging the work, driving connec
tions for reciprocating the feed tube constructed
and arranged to advance the feed tube beyond
a position in which the work is engaged against
the stop, and a resilient connection in said driv
ing connections of suf?cient strength to cause
slippage of said friction means on the work when
75 engaged against the stop.
2. In a feed mechanism for a screw machine,
the ‘combination with a stop against which the
work is fed, of a rotary feed tube including means
for frictionally engaging and advancing the work
against the stop, driving connections for advanc
ing and retracting the feed tube between pre
determined limits constructed and arranged to
advance the feed tube beyond a position in which
the work is engaged against the stop, a feed
adjustment in said connections to vary the feed
and return stroke of the feed tube, and a re
silient connection in said drive independent of
said feed adjustment to provide a safety cushion
against excessive resistance to the advance of
the feed tube, said resilient connection being of
sufficient strength to cause slippage of said fric
tion means on the work when engaged against
the stop.
3. In a feed mechanism for a screw machine,
the combination with a stop against which the
work is fed, of a rotary feed tube including means
for frictionally engaging and feeding the work
against the stop, a feed member, driving connec
tions for positively advancing and retracting the
feed member between predetermined limits ‘con
structed and arranged to advance the feed tube
beyond a position in which the work is engaged
against the stop, a feed adjustment in said con
nections to vary the feed stroke of the feed mem
ber, and a resilient connection between the feed 30
member and tube to provide a safety cushion
against excessive resistance to the advance of
the feed tube, said resilient connection being of
su?icient strength to cause slippage of said fric
tion means on the work when engaged against ' El
the stop.
4. In a feed mechanism for a screw machine,
the combination with a stop against which the
work is fed, of a feed tube having means for
frictionally engaging the work, driving connec 110
tions for reciprocating the feed tube between
predetermined limits constructed and arranged
to advance the feed tube beyond a position in
which the work is engaged against the stop, and
a resilient connection having a limited yield and
of sufficient strength to cause slippage of said
friction means on the work when engaged against
the stop, and a safety device rendered opera
tive by relative movement of the feed tube and
drive connections beyond the limit of said yield
to operatively disconnect the feed tube from said
driving connections.
5. In a feed mechanism for a screw machine,
the combination with a stop against which the
work is fed, of a rotary feed tube including
means for frictionally engaging and feeding the
work against the stop, a feed member, driving
connections for advancing and retracting the feed
member between predetermined limits construct
ed and arranged. to advance the feed tube beyond 60
a position in which the work is engaged against
the stop, a resilient connection between the feed
member and tube having a limited yield and
of suf?cient strength to cause slippage of the
friction means on the work when engaged against
the stop, and a safety device including a shear
pin rendered operative by relative movement of
the feed tube and feed member beyond the limit
of said yield to operatively disconnect the feed
tube from the feed member.
I
6. In a feed mechanism for a screw machine,
the combination of a rotary feed tube, a feed
slide, driving connections for advancing and re
tracting the feed slide to feed the work, and a
resilient connection between the slide and the 76
4
2,120,842
tube comprising a latch on‘v the feed slide ar
ranged for locking engagement with the feed
tube to prevent axial movement of the latch and
‘feed tube, and a spring connection between the
latch and feed slide acting to maintain the latch
in a relatively advanced position on the feed
slide in the direction of feed.
7. Ina feed mechanism for a screw machine,
the combination of‘ a rotary feed tube, a feed
10 slide, driving connections for advancing and re
tracting the feed slide to feed the work, and a
resilient connection between the slide'and tube
comprising a bearing supported on the tube
against axial movement relatively thereto, a latch
15 on the feed slide arranged for locking engage
ment with the bearing to prevent relative axial
movement of the latch and feed tube, and a
spring connection between the latch and the feed
slide acting to maintain the latch in a relatively
20 advanced position on the feed slide in the direc
tion of feed.
8. In a feed mechanism for a screw machine,
the combination of a rotary feed tube, a feed
slide, driving connections for advancing and re
25 tracting the feed slide to feed the work, and a
resilient connection between the slide and tube
comprising a bearing supported on the tube
against axial movement relatively thereto, a latch
on the feed slide arranged for locking engage
30 ment with the bearing to prevent relative axial
movement of the latch and feed tube, a pivotal
support on the feed slide on which the latch
moves axially and turns in a plane normal to
the axis of the feed tube, and a spring connec
35 tion between the latch and the feed slide acting
to maintain the latch axially in a relatively ad
vanced position on the feed slide in the direction
of feed.
9. In a'feed mechanism for a screw machine,
the combination of a rotary feed tube, a feed
slide, driving connections for advancing and re
tracting the feed slide to feed the work, and
a resilient connection between
comprising a latch on the feed
45 locking engagement with the
vent relative axial movement
the slide and tube
slide arranged for
feed tube to pre
of the latch and
feed tube, and spring connections between the
latch and the feed slide located on opposite sides
of the feed tube arranged to yield against an
50 excessive resistance to the advance of'the feed
tube with the feed slide.
10, In a feed mechanism for a screw machine,
the combination of a rotary feed tube, a feed
slide, driving connections for advancing and re
tracting the feed slide to feed the work, and a
resilient connection between the slide and the
tube comprising a bearing supported on the tube
against axial movement relatively thereto, a latch
arranged for locking engagement with the bear
60 ing to prevent relative movement of the latch
axially of the feed tube, a pivotal support for
the latch on the feed slide arranged to permit
movement of the latch axially of its pivot, a
second support for the latch on the feed slide
65 located on the opposite side of the bearing from
said pivotal support, and springs associated with
each of said supports acting on the latch to
maintain the latch in a relatively advanced po
sition on the feed slide in the direction of feed.
70
11. In a feed mechanism for a screw machine,
the combination with a stop against which the
work is fed, of a rotary feed tube and a feed
collet for frictionally engaging and advancing
the work against the stop, a feed slide, driving
connections for advancing and retracting the
feed slide between predetermined limits" to feed
the work frictionally against the stop, a latch
on the feed slide arranged for locking engage 5
ment with the feed tube to prevent relative axial
movement of the latch and feed tube, and a
yielding connection between the latch and feed
slide acting to maintain the latch in a rela
tively advanced position on the feed slide in the 1O
direction of feed including a compression spring,
a spring supporting member and a shear pin. ’
12. In a feed mechanism for a screw machine,
the combination with a stop against which the
work is fed, of a rotary feed tube and 'a feed 15
collet for frictionally engaging and advancing the
work against the stop, a feed slide, driving con
nections for advancing and retracting the feed
slide between predetermined limits to feed the
work frictionally against the stop, a latch on
the feed slide arranged for’locking engagement
with the feed tube to prevent relative axial move
ment of the latch and feed tube, and a yielding
connection between the ‘latch and feed slide com—
prising a latch supporting member slidably 25
mounted on the feed slide, and a spring con
nection between the latch supporting member
and the feed slide acting to maintain said mem
her and latch engaged thereby in a relatively
advanced position on the feed slide in the direc 30
tion of feed.
13. In a feed mechanism for a screw machine,
the combination with a stop against which the
work is fed, of a rotary feed tube and a feed
collet for frictionally engaging and advancing 35
the work against the stop, a feed slide, driving
connections for advancing and retracting the feed
slide between predetermined limits to feed the
work frictionally against the stop, a latch on
the feed slide arranged for locking engagement 40
with the feed tube to prevent relative axial move
ment of the latch and feed tube, and a yielding
connection between the latch-and feed slide com
prising latch supports slidably mounted on the
feed slide on opposite sides of the feed tube, and 45
spring connections between each of- said supports
and the, feed slide'to maintain said supports and
the latch engaged thereby in a relatively ad
vanced position on the feed slide.
14. In a feed mechanism for a screw machine, 50
the combination with a stop against which the
work is fed, of a rotary feed tube and a feed
collet for frictionally engaging and advancing
the work against the stop, a ‘feed slide, driving
connections for advancing and retracting the 55
vfeed slide between predetermined limits to feed
the work frictionally against the stop, a latch
on the feed slide arranged for locking engage
ment'with the feed tube to prevent relative axial
movement of the latch and feed tube, and a 60
yielding connection between the latch and feed
slide comprising a hollow latch support slid
ably mounted on the feed slide and having the
rear end thereof closed, a compression spring
housed within said hollow support connected at 65
its forward end to said support, and a c0nnec~
tion between the rear end of the spring and the
feed slide including a shear pin acting on said
spring to maintain the‘ support and latch en
gaged thereby in a relatively advanced position 70
on the feed slide.
CHARLES A. RICH.
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