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Патент USA US2404234

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July 16, 1946.
' 2,404,234
Filed Aug.- 24, 1938 .'
4 SheeNtS-I-Sheet' 1
I [Va/‘lam?v 5 Kerr: ’
, July 16, 1946.
- 2,404,234
Filed Aug‘. 24, 1938
4 Sheets-Sheet 2
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July 16. 1946
w. E. KERR
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Fi'led’Aug. 24,, 1938‘
‘- 2,404,234
4 Sheets-Sheet a
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July 16, 1946.
’ W. E. KERR"
Filed Aug. 24, 1958
4- Sheets-Sheet 4
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“Wallace E. Kerr. '
Patented July 16, ‘1946
Wallace E. Kerr, Youngstown, Ohio
Application August 24, 1938, Serial No. 226,477
32 Claims. (01. 205-2)
This invention relates to a drawing machine
of the kind in' which lengths of metal sections are
drawn through restricting or forming dies for
the purpose of reducing or forming the cross-sec
tional area or shape of the pieces. In machines
for this purpose it is common practice to provide
ment of the bits as mentioned above and results
in a machine requiring less. maintenance and
having a higher long term ef?ciency'than any
such machines heretofore devised. '
A further object of the invention is the pro- ,
vision of improved apparatus vfor returning the
grip bit carriage to the die block upon the com
pletion of a drawing operation and this includes
means to quickly return the carriage to a posi
a die block, a frame or track extending away
from the leaving side of the die or dies, a car
riage' movable along the track and having means
to grip reduced'end portions of the pieces ex
tending through the dies, means for removing the
pieces from the machine, as shown in my prior
tion adjacent the block, means to retard the
speed of the carriage as it approaches the block,
U. S. Patent #1940354, for example, and a mov
the block until the grip bits have effectively en-q
and means to hold the carriage in contact with
ing chain to move the carriage away from the die
gaged the reduced ends of the bars or tubes ex-"
15 tending through the dies of the block. These
To e?ect substantial economy in the produc;
features are of importance since a quick return
tion of drawn shapes it’is, of course, essential
of the carriage decreases the time consumed in
that the drivingmachine be automatic in its op
unproductive phases of the operation of the ma
eration--requiring but one operator for its oper
chine, the reduction in speed prevents injury to
ation, and capable of wide ?exibility in use While
the carriage and die block assemblies due to
requiring a minimum of time to change over
shock, and the elimination of rebound of the
from one kind of operation to another. By the
carriage after contacting the die block‘ enables
latter is meant the rearrangement of the machine
the grip bits to engage the stock ends at a posi
for the production of shapes having different
tion very close to the dies thereby reducing the
cross-sectional shapesor sizes and as this nor
length of the reduced or pointed end required to
mally involves an interchange in the‘members
be placed on each length of stock which reduced
used to grip the reduced end of the stock extend
ends must subsequently be severed for scrap. By
ing through the die, the construction of the grip
reducing the percentage of scrap evolved in the
bit assembly on the carriage is such that the grip
drawing‘ process substantial economies are ef
bits may be readily rearranged and interchanged
with a minimum of delay. Inasmuch as the ma
chine may be of su?icient capacity to draw but a
single length of bar or tube of one size and a
plurality of lengths of smaller size the construe
Yet another object of the invention is the pro
vision of an improved meansto retain the chain
engaging hook in retracted position when the
carriage is returned to the die block and an im
tion enables either one or a plurality of such
proved mechanism for operating the grip bits
lengths to be simultaneously drawn, depending
upon the fall of the hook as the carriage reaches
the die block whereby no undue stresses are im
posed on any of the parts, wearing surfaces may
‘be of substantial area, and the mechanism, as
40 a whole, may be subjected to continuous and
on the size and material of the stock being drawn
and the manner in which the machine is set up.
It is one object of my invention to provide a grip
bit and grip bit operating assembly for use in a
machine of the kind described in which the bits
are of simple and inexpensive design and ca
heavy service with a minimum of repair and ad- I
pable of being readily interchanged when pre
A still further object of the invention ‘is the
paring the machine for operation on different
provision‘ of a cable mechanism for returning
45 the grip bit carriage to the die block in which
Another object of the invention is to provide
the shaft of the cable driving sheave is relieved
an improved construction for the grip bit oper
from stresses imposed by the static tension in
ating assembly in which substantially the entire
the cable and inwhich the cable maintains a
mechanism thereof is housed within the frame
?xed position axially of the driving sheave at all
of the carriage thereby minimizing the danger 60 times whereby the elements may be of simple
of injury to such mechanism by impact between
and economical design and delays incident to, any
the frame and/or mechanism and other objects.
carriage return mechanism failure may be sub
This feature of design is accomplished without
stantially obviated.
- ,
sacri?cing any of the desirable‘ attributes con
These and other objects and advantages of the
cerning the ruggedness and ease of interchange‘ 65 invention will become apparent from a consid.
through the dies l6,'the chain 22 having a reach
extending along the bench Ill between the tracks
I! and continuously moving away from the dies
16. A hook 2i connects thegrip bit carriage with
the chain 22 and in the normal operation of
the machine the hook 2i automatically drops and
engages the chain 22 as the carriage 20 reaches,
the die block l3 and disengages from the chain
upon completion of the drawing operation thus
enabling the cable 25 to return the carriage back
accompanying drawings of a preferred embodi
' ment of the invention.
Throughout the several
views of the drawings, similar reference numer
3 V als designate similar parts; and
Figure 1 is a partial side View of a drawing
machine embodying the principles of my inven
Figure 2 is a plan view of the'structure of Fig
ure 1;
Figure 3 is a plan view, partly in section, of
the grip bit carriage assembly of the machine of
Figure 1;
to the dies.
cluding the preferably unitary frame membervZ?
having alongitudinal recess for the reception of
-, the hook 2!, as shown in detail in Figures 3 to
11, inclusive. Hook 2| is pivotally mounted on
the transversely extending pin ‘28 and is pro
illustrating the manner in which the correspond.
ing assembly of Figures 2 and 3 is changedin
order that the machine may simultaneously draw
two bars or tubes instead of three as in Figures
vided on its upper surface adjacent its outer end
with the attached member 29 having laterally ex- 7
tending portions for engagement with the shoul
ders 30 on the side arms of the pivotally mount
ed fork 29'. The lower ends of the arms of fork
Figure 5 is a plan view, partly in section, of
a portion of a modi?ed form of grip bit assem
29’ are pivoted to frame 26 by the spaced axially
bly, illustratingv the manner in whch the corre
sponding assembly of Figures 2 and 3 is changed
‘ to draw but a single tube or bar at each traverse ~,.
of the carriage;
Figure 6 is a plan view, partly in section, of
another modi?ed form of grip bit assembly;
Figure '7 is an end view of the grip bit carriage
of Figures 2 and 3; .
Figure 8 is a sectional view of the grip bit car
riage taken along the line 8—8 of Fig-ure 3;
Figure 9 is a longitudinal section of the grip
bit carriage taken along the line 9—9 of Fig
Figure 10 is a longitudinal section of the grip
bit carriage taken along the line I 0—|0 of Fig
ure 3;
Figure 11 is a sectional view taken along the‘
line Il-H of Figure 3;
_ Figure 12 is a sectional view taken along the
line |2—l2 of Figure 2; and
Figure 13 is a wiring diagram, illustrating the
energizing and control circuits for the carriage
return mechanism.
Referring now.more particularly to Figures '1
and 2 of the drawings, the machine to which the
various features of my invention may be applied
consists of a bench l0 having a pair of spaced
The grip carriage assembly of my invention, in
Figure 4 is a plan View, partly in section, of 'a
portion of a modi?ed form of grip bit assembly,
2 and 3;
eration ofthe following detailed speci?cation and
aligned pins 3| and with the member 29’ in re
tracted position, as shown in Figure 9, the shoul
ders 30 and laterally extending portions of mem
ber 29 cooperate to maintain the hook in raised
position. An outward or counterclockwise move
ment of member 29' moves shoulders 39 away
frommember 29 allowing hook 2| to rotate about‘
pin 28 and the hook to impinge on chain 22.
Fork 29’ is operated by rod 32 which pivotally
connects with a pin 33 extending laterally‘from
the upper portion of the ‘fork and which is biased
by coil spring 34 toward'the die block end of the
carriage to normally hold the fork in retracted
position. Rod 32 is, in turn, actuated by the rod
35 the die block ‘end of which is adapted to en- »
gage a projection 36 on block 13 as the carriage
4-0 approaches the die block. '
Carriage frame 2%] is provided at one end with
a transverse recessed slot 35' into which'is adapt
ed to slide the grip bit block 31 having inner
?anges 38 ?tting within the recesses to prevent
longitudinal separation of the frame and block
31. Referring to Figure 3 which illustrates the
grip assembly as set up to simultaneously draw
three bars or tubes, the block 3'! is provided with
three pairs of converging guide channels 39 each
parallel tracks H on which travel the wheels 23 50 adapted to slidably receive a grip bit 49 having
an angular disposed serrated portion 4! to grip
supporting the grip bit carriage frame 20‘. Con-v
the reduced ends IE of the bars or tubes being
nected with one end of the bench H3 is the die
drawn. The channels-39 converge toward the
supporting frame. generally indicated at 12 which
outer face vof block 37 whereby movement of the
is adapted to slidably receive the die block l3,
theformer being'p'rovided with grooves l5 into 55 bits of a pairtoward said face cause the ser
rated portions thereof to move toward each other
which the ribs 14 of the latter move to prevent
and securely clamp the intervening end I8 of.
relative movement between the parts during the
the bar or tube. The design of the parts is such
normal operation of the machine. Block [3 sup
that the outer side surfaces of the channels of
ports the restricting or forming dies is through
a pair, which surfaces receive the entire thrust
which rods or tubes H are to be drawn and to
imposed by the clamping of the rod or tube por
initiate operation of the draw, the rods, tubes or
tion l8, are uninterrupted through the length of
other lengths I‘! are ?rst provided with an end
the channels thereby increasing the wearing Sur
portion l8 reduced in diameter to pass through
face and adding to the life of the assembly. The
the openings‘ in dies l6 for engagement by the
gripping means carried by the frame 20. The 65 grip bits AG which may be constructed of stock
‘which is square or rectangular in cross-section
latter is provided with a depending side member
are. of simple design for economy of construction
24 to which the ends of the carriage moving
and inasmuch as they are of uniform cross-sec
cable 25 is attached, one end having an adjust
tion they may be readily removed individually
able connection 25 with the member whereby the
through their respective channel openings to the
tautness of the cable may be varied. In accord
ance with usual practice an endless and contin
outer face of the block 31. For a purpose to be
uously moving chain 22, only a portion of which
later described, eachof the grip bits adjacent
its end opposite the serrated portion is provided
' vis shown, is utilized to transmit the power re
quired to move the carriage 20 away fromthe
die block l3 and draw the shapes being worked
with a vertically disposed bore 42.
Grip bits 40 are slidably moved longitudinally
in their respective channels by the plungers 44
' Returning to Figures 1 and 2 of the drawings,
which abut the inner ends of the bits to move
the apparatus provided to return‘the grip bit
the same outwardly and by the inverted U-shaped
connecting‘ rods 45 the adjacent ends of which
carriage to the dies and to move the carriage
independently of the chain 22 when no load is
are received within the bores 42 to move the bits v
imposed includes the cable. 25, as,.mentioned
inwardly. The outer faces of the. plungers 44
and the adjacent faces of the grip bits 49 are
above, which is driven by a novel driving arrange
ment now to be described. I provide a driving
plane and parallel thereby providing substantial
motor ‘H having an attached speed reducing unit
12 the driven shaft 13 of which has keyed thereto
contacting areas for the transmission of the
forces required to move the bits into tight en 10 inner and outer ‘driving disks ‘l4 and ‘[5, respec
tively.‘ See Fig. 12. .Disks ‘l4 and 15 are urged
gagement with the stock being worked on. Plung
toward each other by a spring 16 interposed be-'
ers '44, which in the embodiment of Figure 3 are
tween a nut ‘H on the outer end of extension
six in number, are mounted in parallel relation
18 of shaft 13 and the outer surface of disk 15.
for sliding movement longitudinally of the bench
ID in suitable bores provided in the frame 20. 15 Interposed between the disks ‘l4 and 15 is the
double groove sheave 80 driven solely by the in
Adjacent the end of each plunger opposite its
ner faces of the disks 14 and ‘I5. Suitable fric
grip bit'engaging surface is a collar 41 which is
tion material 81 is interposed between the faces
suitably secured ‘to the plunger 44 and which is
of sheave 30 and the inner faces of the disks
provided with a vertical bore 48 aligning with a
bore 49 in the plunger to receive the other end 20 mentioned. Spring '56 is so adjusted that Sllf—
?cient power to move the carriage may be trans
of the inverted U-shaped connecting rod 45. 001- ’
mitted through the friction clutch thus provided
lar 41 being secured to the plunger moves the rod
but if excessive resistance is, encountered, the’
v45 in accordance with the movement of the plung
clutch will slip. A single groove sheave B3 is sup
er. The collars 41 are each provided with a de
ported on an inclined axis on one side of the
pending lug 5i] slidably receivedwithin slots 5|
driving sheave as and a second single groove
in the frame 20 to maintain the collars and con
sequently the rods 45 in proper vertical position.
Plungers 44 are urged to simultaneous longi
tudinal movement upon pivotal movement of the
hook 2| by meansof the connecting linkage now ;
to be described. Extending transversely of the
upper portion of the frame 20 is the pin 53 on
which is rotatably mounted the sleeve 54 having
sheave 84 is mounted on an inclined axis on
the other side of sheave 8B. A pulley 85 is
mounted adjacent the end of the bench l0 oppo
site the die block and a second pulley 86 is
mounted adjacent the die block; Beginning with
that end of cable 25 ?xed in relation to member
24 the cable may be t'raced—over pulleytG, sheave
attached thereto the downwardly extending wide
80, sheave 84, sheave 83, sheave 8e, pulley 85 and
ly spaced arms GI and the centrally disposed :
spaced arms 55. Spanning the outer free ends
of arms 55 is the pin 56 which is rotatably mount
ed in aligned apertures in the'arms and which
is provided with a diametrically disposed threaded
bore for the reception of a hollow screw 57. The 4 O
back through adjustable connection 26 to member
latter is rotatably mounted on a threaded rod 59’
which is rigidly connected at its lower end with
a fork 59 pivotally attached at 60 to the hook
2| at a point adjacent the pivot 28. The upper
end of screw 51 is provided with an attached col-,
lar 51? and a second collar 58 is screw threaded
onto. the outer end of threaded rod 59'. By loos
ening collar 58, screw 51 through collar 51' may
readily be. rotated thus providing an adjustment
of the interval between pin 55 and pivot ~50; A T
transverse member 62 having apertures 63 for
the accommodation of plungers 44 is connected
with the lower free ends of the arms 61' by the
U-shaped links 64 which are rigidly attached at
their one end to the transverse member 62 and
which are pivotally connected, by means of pins
v55, with the arms 6| at their other ends. As.
shown in Figures 9 and 10, the frame 20 is pro
vided with a cavity 66 of sufficient size to ac
commodate member 62 and to allow said member 60
a limited movement longitudinal of the bench It]
with respect to the frame 20. A coil spring 61
is interposed’ between each collar 41 and the
transverse member 62 and a second set of coil
24. The purpose of the inclined axes for sheaves
8'3 and 84 is to .provide aligning guide surfaces
between the cable leaving increment of one sheave
and the cable entering increment of the subse
quent sheave. The arrangement provides a length
of contact between the cable 25 and the driving
sheave 80 equal to or. slightly greater than the
entire circumference of the sheave 80 thus pro
viding a drive of sufficient capacity to quickly
move the carriage along the bench. Also the ar
rangement enables the drive to be accomplished
by the use of' but two parallel grooves in the
‘driving sheave thereby dispensing with any move
ment of the point of application of the force
caused by‘tensioning of‘ the cable, axially along
the shaft supporting the sheave. Consequently
bending moments of less value are applied to the
shaft and the shaft and its support may be
made lighter in construction and will be less like- _
ly to be damaged in use.
The control circuit for the grip bit carriage
return motor ‘H is illustrated schematically in
Figure 13. Motor ‘His of the reversing type and
is provided with a magnetic brake I12 of the
usual kind in which the braking force is applied
by a spring and released by a solenoid, as 92,
which is energized simultaneously with energi
zation of the motor. A normally closed limit
switch 88 having an operating arm 89 adapted to
springs 68 are interposed between the member 62
and the enlarged ends 69 of the plungers 44. It can
be engaged by depending member 24 of the car-‘
riage" is positioned on the bench If] a number
therefore be seen that longitudinal movement
of the member 62 along the axes of the plung
ers 44 causes the plungers and consequently the
grip bits 40 to move along their longitudinal axes
and the bits to move to their operative or inopera
tive positions. As shown in Figure 3, the links
54 are positioned intermediate certain of the
of feet from the die block [3 and a second double
throw limit switch 9dghavingvan operating arm
9! also adapted to be engaged by depending
member 24 is positioned adjacent the die block in
such manner thatwhen the outer face of block '
31 is within a short distance of the die block or
is in contact therewith, the switch will be in right
plungers 44 so as not to interfere with the proper ,
closed position as viewed in Figure 13. A third,
75 limit switch 94 having an operating arm 94a
operation of the latter.
operated; by‘ a member Stir-"(see Figure 12)
move- the. carriage, away from. die. block. ‘Refer:
ringznow to,Figures.3,.8, El, and 1_0 of the drawings,
as the. carriage 20; apprcaches the. die... the stock
I1; to be drawn, will. have their reduced ends. I 8
through friction clutch 8:35’ driven by sheave, 83
is adapted to bev operated upon reversal or direc
tion of movement. of the. cab1a25. The. operation
in position extending: through the dies; and. these
ends. will: be ‘receivedbetween the opened serrated
jaws. 41. oi. the. grin bits 4.1L. As the. apprcaqh is
.ccmnleted the engagement of red. 35. with. projec
‘ofathis assembly is ‘such that upon a. change in
the direction of movement. ofthe. cable, and conse
, quently of sheave 83, the member 8311 rotates
until the switch arm 94a. is thrown to its other
tion 35 moves. the tort; 29'. cpuntercloclsrvisc re:
leasmgiatch. 23:30, and. allqwine, hook‘ 2. I befall
onto chain 22..
sleeve 56 to be ro-i
limiting position whereupon member 83a stops—.
further rotation of 831* being permitted by‘ the
frictional connection between 33,’ and..83aH
vFigureg13 illustrates. the conditionjpf; the. con
trols; immediately after the; return switch S2‘ has
been manually actuated and the carriage is re
turning to] the dies. Actuation of S2 estab-; ,
lished the relay circuits-line, conductor I66, lll?a,
IIlBb,*solenoid S051, conductor Hi5, I85a~,. switch
‘ ’S2, conductor Mia, III, H2, normally closed
switch SI, and back‘ to line. Energization of
solenoid S05. closed the switch S5 and SM thereby #
energizing the return windings of the motor thru
line, conductor H36, I??c, switch S5a, conductor
96a, 96, motor 1|, conductor 91, 98, I3ila, switch
S5, conductor I30, H9, IE6, “2, switch SI, and
back to line.
Simultaneously a holding .circuit
- ,
M and movinalinks 64. tower-dine. sriprbiis,
es. the transverse member, 6.2- is cmmected. with
the links Edit Wi11~a1§<><be moved. towarclthe grip
hit end of the Qarriaeeami. thrqush Springs 6*?
acting on plungers 44' it will. urge the plungers
toward the same end of the carriage, As. clearly
shown in Figures, such movement of the plungers
Will move the grip. bits 40 along their channels
‘and the. bits of each pair will move toward. each
other alld'securely clamp the stock ends; I3 to the
carriage. Now as the bight of the hook .2! drops
intov a, dwell of the chain 22, if it did not dovso
initially, the carriage, and consequently the stock
back. to line was established and consequently
will be drawn along the bench._ During that in!
terval between the time the carriage, reaches the
die block and the time the chain 22, through hook
2! begins to move thev carriage away from the
when switch S2 is- released. Return of the car
and the block is maintained through. cable 25 vby
for’ solenoid S05- consisting of line, conductor I06,
tilt, 88, 99., 138a, S5, I39, H9, H6, H2, SI, and
the return energization of-motor 1I continues 30 block the pressure, contact between the carriage
motor 1!, the friction clutch 14, ‘15,811,8I (Figure
riage continues at'uniform speed, which by reason
12) slipping.
' ’
of the arrangement to be hereinafter described
To prevent energization of. motor, 1-! opposing.
may be.’ considerably higher than that previously
employed, until limit switch 88 is actuated by 35 forward movement of the carriage during the‘
engagement of its operator 89 by member 24
depending from the carriage. Opening of switch
88’ breaks the holding circuit above de?ned and
deenergizes solenoid S05 allowing switch S5 and
drawing cycle, the switch 80 normally ‘returns
to the position shown in Figure 1.3 and upon sllClil '
movement and consequent reversal of direction
gizing circuit. Opening of switch S5: also breaks
of movement of cable 25, switch 9,4 will close. As
shown in Figure 13, the switch 9t! deenergizes sole
ncid. 50.5. by opening circuit thrcueh~1ina 1.96.,
the relay'circuit—~line, conductor I31, I26, sole
noid S08, conductor H2, 98, I3?a, S5, I130, II9,
H6, H2, SI, and back to line; deenergizing sole
H380, [6.8, 1815, III, I12‘, SI, and back to'line as
previously de?ned, opening}, switch'S5j and 85a
Consequently; as the carriage reaches
switch 88, and motor 1! is. deenerg-ized and the
brake I12 is applied which in addition to-apply
H2, H6, I224, solenoid 92, I22, IZI, I21, 94,120,
I33, -I3I, and back to line. Consequently the
brake is released and' is inoperative, during the
3, S-Ea: to, open thereby opening the motor Vener
noid S08 and opening switch S8 which switch 45 which opens the motor energizing 'circuit—line,
I06,‘ i860, S521, 96a, 9d, motor ‘II, 91, 98, ISM,
maintains an energizing circuit..—line, switch SI,
S5, I30, H9, H6, H2, and/SI; previously de?ned
conductor H2, H6, I24, brake releasing solenoid
and at the same time. the solenoid 92 which re
92, conductor 122, I23, S8, I25, I33, 1.3L and line;
for operation of solenoid 92 and release of brake 50 leases brake I12. is energized‘ by circuit-line, Si,
ingv its e?ect to the motor 1'1 per se also acts on
the cable 25 thereby exerting a braking action
on further movement of the carriage.
Inasmuch as the carriage assembly is of' con
siderable. weight substantial inertia'is inherent in
the same when it is moving- and it will continue
to drift, some distance after motor H is deene-r
gized and brake I12 is applied. Brake I12, and,
if necessary, friction drive ‘M, 15:, 80, are so ad?
justed that the carriage will drift ‘to. substantial
engagement with the, die blockv or- at least: until
the limit switch 99 is engaged._ This results“ in
opening above’ de?ned holding circuit, and ener
gizing solenoid S05. through line, I95, I??a, 1115?),
S05, I535, I83, assess, IE2, Inga, SQ, “33a, I08,
I54, HI, H2, SI, and back to line and closing
drawing traverse of the carriage. ‘
In additionto the above described. features of
' the‘return motor control circuit I provide are
rangementswhereby the carriage may be con.
trollably moved either forward or backward along
the benchregardless of the position of the same.
The former is accomplished by depressing switch
S4 which energizes solenoid Soii. through line,
see, mac, meg‘, set, an, er, web, M8,. me, ill,
H2, SI, and back to line, Energization of. So6
closedv switch S6 and Sta. providing the. motor
energizing circuit—.lin_e, I05, “15d,- SSa, II 4., 9,5, _.
H, us, 1se.c.,,sa.|so.b, M9, M15, uz, s1, and, back
to line. Upon release of switch S4 the circuits
mentioned are opened and the motor is deener
gized and the brake I12 applied thereby providing
aver-y sensitive carriage positioning- contrcl, To
switch S5 and Site establishing'mctar energizing
circuit.—line, H16, ‘late, 8.5a, 96a, 96, motor 1!,
98, mm, S5, I39, N9, M5,, N2, SI, and back
. release brake. I12. upon such motor» energization
to line-which ener'giz'ation of‘ motor 1-! ‘will move
the carriage into. positive engagement with the
die block/and maintain the. engagement until the‘
through, line, III-ll, IIJ, Sol, I31, Mile, S6, I332),
'19, "51412,. SI’, and. line which solenoid closes
the closing, of switch S5, energizes solenoid So‘!
switch S‘! providing a circuit-lineSj, H2, H6,
‘main draw chainr22, through hock 2|, begins to 775 I24, 92, :22, IZI, “5, s1, U8, I33, I31, and. line-T
thereby energizing brake releasing solenoid 92.‘
wardly through aligned openings in the frame and
The carriage may be controllably moved to
ward the dies by depressing manual switch S3
which establishes the circuit—line, I06, Iilta,
block. To remove the block it is only necessary to
withdraw pin 31' and connecting rods 45'where
upon the block may be slid transversely out of
. the carriage frame. As apparent from Figure "3
I061), S05, I05, I53, me, S3, H0, Hill, H1, H2,
SI, and line-and closes switch S5 and 84a clos
the frame 20 is provided with openings allowing
ing the motor energizing circuit de?ned above.
Simultaneously solenoid S08 is energized thru—
ready access to the rods 45. Block 31 may be re
placed, for example, by a block 3'“ as shown in
Figure 4 in which but two pairs of grip bits 40I
line, I3I, I25, S03, :32, 88, IBM, S5, i330, IiE,
I I6, I I2, and SI—closing switch S8 thereby ener
10 are included.
gizing brake releasing solenoid 92 through line,
The set up may be used to draw .
stock I8I of larger size than it would be possible
SI, H2, H6, I24, 92, I22,I23,SS,I25,133, I3!,
to draw vin a triple machine. Certain of the
plungers 44 and certain of the collars 41 and rods
pleted thereby are opened, the motor deenergized
45 would be utilized to operate the grip bits 40I.
and the brake applied. A fourth. manual switch 15 Aside from the withdrawal of rods 45 which is an
SI is provided to stop the carriage when moving
exceedingly simple operation no parts of the
as a result of energization of motor ‘I! by previous
grip bit operating mechanism need be touchedin'
closure ofSZ or bythe failure of switches S3
the changing of individual grip bits or in the
and. line. Upon release of $3 ‘the circuits com
and S4 toopen upon release. Opening of Si
changing of the grip bit block assembly. In Fig
breaks the holding circuit described aboveand 20 ure 5’there is shown a block 312 which houses
opens any circuit established by actuation of
manual switches, S3 and S4.
In operation, the lengths of stock are fastened .
to the carriage in the manner and by the mecha
nism described above and as the chain 22 takes
the load it rises to the position shown in Figure 1
by reason of the elevation of pivot pin 28 and .
thereby lifts the hook 2|. up suf?ciently to posi
but a single pair of grips 402 for operation on
very large or heavy stock. When assembled with
the, other parts of the carriage, a pair ‘of plungers
44 and a pair of rods 45 are utilized for the
actuation of each of the grip bits 402 thus insur
ing adequate force ‘for the actuation of the heavier
bits. In each of three modi?cations thus far de
scribed the operation is the same.
tion member 29 above the'shoulders 30 of mem—
Figure 6 illustrates a modi?ed form of carriage
ber 29'. Spring 34 draws member ze’into re 30 in which the grip bits 403 are not mounted in a
tracted position upon disengagement of rod 35.
with projection 36 and in this position of the parts
the draw continues until the stock I‘! has passed
through the dies. . As the stock __leaves the dies
the carriage will accelerate ina forward direc
tion causing the chain to fall away‘from the hook
2| which will be maintained in upper position’
by the member 29 resting on shoulders ‘30. Inas
much as the transverse member 62 will have
moved forwardly when the hook raised with the
chain 22, the springs 61 between member 62 and
collars 41 will be compressed and as the tension
on the stock I? ceases thereby stopping the out
ward pull on the grip bits 40, the collars 41 and
removable block but are mounted in guides pro
vided in the carriage housing 203. Transverse
member 62 is dispensed with and the collars 623
on each of the two plungers 443 are connected
7 directly with the links 64.v As in the other em
bodiments the plungers 443 move the grip bits’403'
toward each other. and the rods 453 connecting
the bits'with collars 413 ?xed on the plungers
move the bits away from each other.
The adjustment 56, 51, 58 may vary the 'po‘si-v
tion ofthe transverse member 62 or the collars
623 with respect to the carriage frame and
may consequently alter the position of and inter
val or intervals between a pair or pairs of the
plungers 44 will move in a direction away from 451 grip bits when the hook is in raisedposition in
the grip block 31 and by reason of the connect
which position of the parts the grip bits move
ing rods 45 the grips/bits will also be moved in
about the stock ends projecting ‘through the dies.‘
the same direction, to open the pairs thereof and
If the stock is small in cross-section the pairs of
allow the stock ends I‘! to be removed therefrom.
bits are moved closer together to insure tight
The bits remain in open position until the hook 503 gripping upon fall of the hook and if the stock
2| again falls by engagement of rod 35 with the
is large in cross-section the grip bits are moved
projection 36 or by manual manipulation of mem
further apart. This is the only adjustment neces
ber 29', the projecting pin 33' of which provides
sary" for the proper operation of the grip bit op
a hand grip member.
erating mechanism and the design of the assem- ~ >
To provide means to raise the hook 2| during 55 bly permits this adjustment to be positioned in
forward movement of the carriage irrespective of
a readily accessible location. Incidentally this
the load and tightness of chain 22 a pair of cam
is the only element of the mechanism which pro
members I4!) are positioned on opposite sides of
jects beyond the general outer contour of the grip
the chain 22 adapted to be engaged by a pair of
bit carriage assembly, practically all the parts
members I4I secured to and depending from op
thereof being located within the casing or hous
posite side faces of the hook. If the hook is down
ing in nested and protected positions.
when cams I40 are reached, the lower surfaces of
It can thus be seen‘that I havev provided an
depending members I4I ride up the inclined up
7 improved metal drawing machine which accom
per surfaces of members I40 thereby raising the
hook sufficiently to permit attached member 29
to snap over the shoulders 30'of member 29' and
retain the hook in raised position.
A dashpot I44 acting through pivoted lever
I45 engageable by the carriage as it nears the die
block may be employed to cushion the impact be
tween the carriage and the die block.v ' '
plishes the objects initially set out. The devised
control for the movement‘ of the grip bit *carriage
enables the machine to be operated at higher pro
ductive speeds and allows a reduction to be ef-‘
feet-ed in the amount of the stock utilized in the
provision of the requisite reduced end for each
70 length'thei'eby substantially reducing the scrap
losses incident to the operation of the process.
Assuming a constant supply of pointed stock to
a block 31 which is slidably mountedv in the car
be made available atthe dies by any of the means
riage frame 20. Block 31 is retained in position,
well known in the art the drawing machine opera
in the frame by the pin 31’ which passes down; 7-3 tonneed normally to perform but few operations
As stated above, the grip bits ‘40 are carried in
being removable without disturbing ‘said'r?rst
during each drawing cycle ‘as the momentary
depressing of the return control switch S2 upon
completionof a draw will result in automaticcon
trolof the subsequent movement of the carriage
in the manner described above. The grip bits
iwhich ‘must be replaced from time to time be
mentioned means.
2. In av drawing machine, a carriage havmg' '
guide surfaces thereon, grip bits carried by said
carriage and slidable along said surfaces into
cause of normal Wear are very simple in design
engagement with the stock to be drawnfcon
trolled means on said carriage to move said gripv
and are consequently economical to construct.
The bits may be readily replaced individually and
bits into engagement with said stock, said'means
applying a resilient force tosaid grip bits, and
means including quickly removable links con
‘ ,necting said Ygrip, bits and ?rst mentioned means‘
for moving saidrgrip ‘bits ‘in the opposite .direc- 7
facilitating‘ the setting up ‘of ‘the vmachine for‘
the entire grip bit assembly may be readily re
moved from and inserted in the carriage thereby
operation on diiierent products. Thewinter
a 3. ‘In a drawing machine, the combination :of
a carriage having an operating ‘member there- a,
changing of theindividual bits 1and of the bit
assemblies requires little technical glinowyledge on
the part of the operator‘and no special tools and
the» same‘ may be accomplished without dis
' turbing the more complicated parts of the ~ma
on, a stock engaging grip bit movably mounted‘
‘ on
into open
‘ and closed positions, a motion transmitting e'le» ‘
chine. By positioning the latch 2S-—30 near the ‘ ment connected with and moved by ?rst saidv
“center of the unsupported mass of the hook 121, 20 mentioned member, means to transmit motion
from said element to said grip bit in a closing di
the latch is subjected to ‘mini-mum force and will
rection, and a movable ‘means connecting said
consequently render long trouble-free service.
Also, less force will be required to release the ‘ element and said grip ‘bit to transmit opening
movement to said grip bit, said ‘last mentioned
latch to allow the hook to drop onto the chain 22.
By providing plane contacting surfaces of sub 25 means being removable without disturbing said
stantial- area between ‘the plungers M and the
‘grip bits the life of the grip bit operating mech
anism will be materially lengthened.
?rst mentioned means.
4. In a drawing machine, the combination of,
Important features of my invention include i .
the arrangement and design of the grip bits and
mally located in an elevated ‘position and adapt
ed when "moving downwardly to originate a mov
bits are individually resiliently urged to closed
gripping assembly for the reason that in all in
stances each of the grip‘bits of .a gripping pair
‘will be independently moved into pressure en
gagement with the end portion of the stock.
‘Springs ??perform the additional function of
‘cushioning the shock transmitted .to member 62
by thesuddenmovement .of the grip bits when
the last .of the stock ‘leaves .the‘die. It should be
observed that the grip bit operating elements
‘44, c5, .41, a2, .61 and 6.3 are rugeedly mounted in
‘protected. positions in the body ofrthe frame 21!
gagement with an element independent of said
30 -carriage,'a second member on said carriage nor
‘the grip bit operating mechanisms. As the grip
‘positions by the springs 58 acting through their
respective plung'ers dd, inaccuracies in the shape
{and disposition o'f‘the pointed ends of the stock
‘to be drawn will not e?ect theoperation of the
a carriagerhav-ing a member movable upon en
ing force, a third member mounted on said car- , ' 7
riage and adapted to move rectilinearly, means ,
connecting said ?rst and second members where
' by actuation of the former will result in down
ward movement of the latter, means connecting
said secondrand third members whereby move
.ment of the second member will be transmitted
40 to the third member, and a stock engaging grip
bit slidably carried by said carriage and adapted_
to be engaged andmoved by said third member.
5. Apparatus according to claim 4 further
characterized in that said connection between.
said second and third members is resilient where
e by
the force furnished by, said second member
will'zbe resiliently applied to said grip bit. ' '
-6. In a ‘drawing machine, a grip bit carriage
and thus are capable of withstanding severe con
comprising a frame, a block removably received ~ 1
jditions of service without failing. While I have so within said frame, said block having a pair of
speci?cally described these elements as being‘
converging channels for the guidance and slid
operable upon. movement of a chain engaging ' able support .of a pair of stock engaging grip bits,
‘hook it should be obvious that other means may ' , said channels extending through the outer face
be employed to transmit drawing movement to > of said block adjacent their point of convergence
the carriage and that other mechanism may be .55 for the reception of an extended end-of the stock
employed to actuate the said elements.,
being drawn and for the insertion and removal of
The above speci?cally described embodiments
the grip bits individually, ancl'meansv movable rel
of my invention should be considered as illus
ative to and carried with the carriage and en
trative ‘only as obviously many changes may be
gaging said grip bits for moving said grip bits
''made therein Without departing from the spirit 60 toward said face, said block and bits being remové
or scope of my invention, the extent of which is
able from said carriage as a unit without dis-
indicated by the subjoined claims.
What I claim is:
1. In a drawing machine, the combination of ‘a
carriage having a member movable upon engage
‘ment with anwelement independent of said bar
;riage,a stock engaging grip bit movably mount
‘ed on said carriage ‘for movement into open and
.closed positions, .a motion transmitting element
turbing said means.
7. In .a drawing machine, a grip bit carriage
comprising a support having a pair of converg
ing channels for the guidance andslidable sup
port of a pair of stock engaging grip bits, said
channels extending through, the outer face of
said support adjacent their point of convergence
for the reception of an extended end of the stock
connected with and/moved-rby said ?rst men 70 being drawn and for the‘insertion and removal
of the grip bits individually, means ‘carried with
said carriage for moving said ‘bits toward said
tion, and removable means connecting said ele- » 1 face, removable means for moving said bits away
from said face, said bits being removable from
‘ment and said grip bit to transmit opening'm?vv
» 1ment to said grip bitfrsaid last “mentioned means Q 7 said support upon the removal of said removable V
jtioned member, means to transmit motion from
said element to said grip bit in a closing direc
means without disturbing said ?rst mentioned
plungers being so disposed that grip bits varla
able in number and disposition may be engaged
8. In a drawing machine, a grip bit carriage
comprising a support having a pair of converg
ing .channels for the guidance and slidable sup
port of a pair of stock engaging grip bits, said
channels extending through the outer‘ face of
said support adjacent their point of convergence
‘for the reception of an extended end of the stock
being drawn and for the insertion and removal of
the grip bits individually, means carried with said
mounted in said frame, means connecting said
carriage for moving said bits toward said face,
of stock engaging grip bits adapted to be en--, ’
gaged and individually moved in one direction
means connected with said ?rst mentioned means
to move said bits away from said face, said second
mentioned means being readily removable with
out disturbing said ?rst mentioned means to per
mit the bits to be removed from said support.
_ 9. In a drawing machine, a grip bit carriage ‘
comprising a frame, a block removably mounted ‘
and‘ operated thereby,
14. In a drawing machine, a grip bit carriage
comprising a frame having movable means
mounted thereon, a plurality of plungers slidably
plungers _ with
said movable
means whereby
movement of said movable means results in resil
ient pressure being applied to said plungers tend
ing to move the same longitudinally, a plurality
by said plungers, and readily removable connect
ing means between said plungers and grip bits
and spanning the points of engagement to indi
vidually move the grip bits in the other direction.
15. In a‘ drawing machine, a grip bit carriage
comprising. a frame, having a movablemeans
in said frame and carrying a plurality of stock 20 mounted thereon, a plurality of plungers slide
engaging grip bits, means within said frame to
move said grip bits into engagement with said
stock, said block and grip bits being removable as
a unit from said frame without disturbing said
ab'lyimounted in said frame, a resilient connec
tion between said movable means ‘and. each of
said plungers whereby movement of said movable
I. means results in independent movement of the
plungers as determined bythe resistance en
10. A grip bit for a drawing machine having a
grip bit carriage with divergent guide surfaces
thereon to slidably mount the grip bits and con
trolled means having plane surfaces to engage
and resiliently urge the grip bits into engagement
with the stock; comprising an elongated member
of substantially uniform cross-section throughout
countered by the respective plungers, and a plu
rality of stock engaging grip bits adapted to be.
‘ engaged and individually moved by said plungers.
16. In a grip bit carriage for a drawing ma
chine a pair of stock engaging grip bits mounted
for movement toward and away from each other,
a hook mounted for pivotal movement about a
rated surf ace for engagement with the stock to be
drawn and a plane surface for engagement with
horizontal. axis which is eccentric with respect to
the center of mass of the hook, means to latch
said hook in upper raised position, and linkage
said plane surface of said coacting grip bit urging
between said hook and said grip bits whereby
the major portion of its extent and having a ser
upward movement of said hook moves said grip
bits apart while downward movement of said
11. A grip bit vfor a drawing machine having
hook ‘moves said grip bits toward each other,
a grip bit carriage with divergent guide surfaces
thereon to slidably mount the grip bits and con M said linkage including a unitary adjusting ele
ment which when adjusted in one direction is op
trolled means having plane surfaces to engage
' erative to move said grip bits toward each other
and urge the grip bits into engagement with'the
stock and quickly detachable links interconnecte
ing said ?rst mentioned means and the grip bits;
' and when adjusted in the opposite direction is
operative to move said grip bits further apart in~
comprising an elongated member of substantially 45 dependent of ‘movement of said hook.
- 1'7. ‘Apparatus according to claim 16 further
uniform cross-section throughout the major por
tion of its extent and having a surface for en
gagement with the stock to be drawn, a recess
for the reception of a portion of one of said links,
characterized in that said linkage includes a‘link '
connected with said hook eccentrically of the
pivot pin thereof, said unitary adjusting element
said recess extending substantially normal to the 60 constituting a portion of said link and being op
erative to vary the eifective length of said link.
direction of movement of thegrip bits.
. 18. In a drawing machine, a grip bit carriage
12. .In' a drawing machine, a grip bit carriage
comprising a frame having a hook pivotally
comprising a frame, movable means mounted
mounted thereon and movable by gravity inv a
thereon, a plurality of plungers slidably mounted
in said frame, .said‘ plungers having outer plane 55 generally vertical plane from upper to lower po
sitions, and means to maintain said hook in up
surfaces, means connecting said plungers with‘
per raised position comprising a member sup
said movable means whereby movement of said»
porting said hook at substantially. the center of
movable means results in longitudinal movement
of said plungers, a plurality of pairs of stock
its'otherwise unsupported mass, said member be
engaging grip bits each having a plane surface 60 ing carried with said frame.
adapted to beengaged by the outer plane surface
19. In a drawing machine, a grip bit carriage
of a contiguous plunger, said plungers being so
comprising a frame having a hook pivotally
disposed that grip bits variable in number of
mounted thereon and movable by gravity in a
pairs, size and disposition may be engaged and
generally vertical plane from upper to lower po
operated thereby.
65 sitions, and means to maintain said hook in up
13. In a drawing machine, a grip bit carriage
" per raised position comprising a member support-'
comprising a frame having movable means
ing said hook at‘ or adjacent its center of mass or
on the opposite side of said center from the piv
mounted thereon, a plurality ‘of plungers slidably
mounted in said frame,‘ means connecting said
plungers with said movable means whereby move-‘
ment of said movable means results in resilient
pressure being applied to said plungers tending
to move the same longitudinally, a plurality of
otal axis of said hook. ' ‘
20. In a drawing machine, a grip bit carriage
comprising. a frame having a hook pivotally
mounted thereon on a transversely extending
pivot pin, a plurality of plungers slidably mount
edin the frame rearwardlybf said pin, means
stockengaging grip bits vadapted to be engaged
and individually moved by said plungers, said 75 connecting said plungers with said hook’ whereby
pivotalmovement of s'aidhook results in resilient
pressure being applied to said plungers tending
to move the same longitudinally, said connecting
‘, means including linkage extending underneath
said pin, a plurality of stock engaging grip bits
slidably mounted in said frame and adapted to
be engaged and operated by said plungers, sub- ’
stantially the whole of said plungers, connecting ‘
' 1. means and grip bits being housed Within said
frame in protected positions.
heat the ?rst mentioned means with the carriage
after the carriage reaches the block,‘ and means
operable upon initiation of movement away from
the block to render said means to urge inopera
'27. A drawing machine comprising a die block,
a bench extending outwardly from said’block,
a grip bit carriage movable along said bench to
ward and away from said block, means to move
1-0 the carriage toward the die block, means to urge
said carriage towardisaid block‘as said carriage
reaches a position adjacent said block, and means
21. Structure according to claim 20 further in
cluding adjusting means to vary the interval of
rendering the urging means substantially inoper
' said connecting means, said adjusting means ex
tending outwardly a short distance beyond the
ative during movement of said carriage away
general ‘contour of said frame. .
from said block.
28. A drawing machine comprising a die, a
bench extending outwardly therefrom, .a grip bit
' 22. In a drawing machine, a grip ‘bit carriage
comprising a frame, a hook pivotally mounted
thereon on a transversely extending axis, ‘a plu
carriage movable along‘said bench, means to
rality of movable stock engaging grip bits mount
move said carriage comprising a cable'secured
ed in said frame 'rearwardly of said axis, and 20 to said carriage, a pulley at each end of said,
bench, a cable driving sheave having at least two '
H means depending below said axis'for connecting
grooves intermediate said pulleys, an idling
said'hook and said grip vbits whereby pivotal
sheave having at least one groove between said
movement of the hook will result in movement
driving sheave and. each pulley, said cable ex
of the grip bits and the said means is in protected
25 tending from the carriage thence over one pulley,
position within the frame.
' 23. A drawing machine comprising a die block,
a bench extending voutwardly fro-m said block, a
grip- bit carriage. movable along said bench to-
ward and away from said block, means to move
the carriage toward the'die block, means to brake
such movement as the carriage approaches the
die block, means to urge said carriage. toward
I said block as saidcarriage reaches a position
adjacent saidv block, and ‘means rendering the
" " urging means substantially inoperative during
one groove of the driving sheave, the idling
sheave adjacent said one pulley, the other idling
sheave, the ‘other groove of the driving sheave,v
the other pulley and thence back to the carriage
whereby the driving sheave vsupport is substan
30 tially
‘relieved from stress arising from static
tension in the cable and the stress resulting from
driving tension in thecable is applied at a con
stant point along the axis of said driving sheave.
29. I-n-a drawing machine having a die, a benchv
'1 movement of‘said carriage ‘away from said block.
24. A drawing machine comprising a die block, ’
‘ a bench extending outwardly from said block, a
extending outwardly therefrom, and a grip bit
carriage movable along‘ said bench; means to
move said carriage along said bench comprising
a unitary cable secured'to said carriage, a cable
grip bit carriage movable along said bench, means
to move the carriage under load away from said 40 driving sheave having at least two'sp'aced parallel
annular cable engaging tracks thereon, a sheave
3 block, independent means to move the carriage
having at least one annular cable engaging’ track
, toward said block, means to brake the movement a
‘ toward the block as the carriage approaches the '
thereon on either side of said cable driving
1, block, means to urge said carriage into engage
sheave; said cable entrained'in series over one of
j ment with said block as said carriage reaches a
the tracks of the driving sheave, one of the tracks
1 position adjacent said block, means to automat
of ‘one ‘of the second mentioned sheaves, one of
, ically connect the first mentioned means with
the tracks of the other of said second mentioned
i the carriage after the carriage reaches the block,
sheaves, and one of the other of the tracks of the
cable driving sheave; whereby the driving sheave _
1 and means operable‘ upon initiation of move
ment away from the block to render saidmeans
support is substantially relieved from stresses due
to static tension in the cable and the stress re- 5
Y to ‘urge inoperative,
sulting from dynamic tension in the cable is ap
'25. A drawing machinev comprising a die, a
plied at substantially a constant point along the
' I bench extending outwardly from said die, a grip
axis of the driving sheave‘
I bit carriage movable along said bench, means
i to move said’ carriage'toward said die' comprising
30. In a drawing machine’ having a bench
and a grip bit carriage movable along'said benchj
1 a cable, means tomove the carriage under load
‘ away from said die, means including said cable to
means to move said carriage along said bench
comprising a, unitary cable secured to said. 1031-‘
1 urge the carriage toward the die, and means re
‘ sponsive to the initiation of movement of said
riage, a ‘cable driving sheave having at least two
i carriage away from said die to render said means
spaced parallel annular cable engaging tracks
to urge inoperative.
thereon, an idler sheave on either side of said
driving sheave; a portion of said cable being en
26. A drawing machine comprising in combinae
1 tion a .die block, a bench extending outwardly ‘
trained over said sheaves in such manner that
the position of the points of application of tension
i from said block, a grip bitoarria'ge movable along
I said bench, means to move the carriage under
load away from said block,‘ movable grip bits on
"said carriage, means to move said vbits to material
‘ engaging positions, independent means to move
said bits to open inoperative positions, means to
, move said carriage towards said block, automatic
in, said cable in either directionof rotation of 7
said driving sheave does not'vary longitudinally’
along the axis of the driving sheave.
371. In adraw head for operation in a mecha
nism of the class ‘described,’attachingmeans for
positively engaging said head with a drawing
said block as said carriage reaches‘ a position ad
I .m'ember, sliding jaw members adapted to engage
the work to be drawn, an operating member for '
each of said jaw members, linkage means actu
ated by said attaching means for operating said .
jacent said block, means to automatically con
operating'members, and spring means inter-con
5 means to brake the movement toward the block
.'as the carriage approaches the block, automatic
‘ means to urge said carriage into engagement with
necting said linkage means and said operating
members, said linkage means, spring means and
operating members being adapted, on movement
ated by said power means upon activation thereof
of said attaching means, to simultaneously move
all of said jaw members toward the work, and
said linkage and spring means being adapted to
thereafter independently move any said operat
ing member and its jaw member after any other
means and said operating members whereby upon
activation of said power means and the subse
quent arrest of movement of one of said jaw
members by contact with said stock piece the
other of said jaw members is continued to be
urged in a direction tending to close onto said
said jaw member has positively engaged the'work.
for operating said'operating members, lost-mo
tion urging means interconnecting said linkage
32. In a drawhead for operation in metal 10 stock piece, and a control device on said draw- '
drawing apparatus having a workhead and means
head for automatically effecting the activation
of said power means thereby automatically ef-‘
supporting said drawhead for movement away
from and toward said workhead, a pair of rela
fecting said closure of said pair of movable jaw
tively movable jaw members adapted to engage
members onto said stock piece‘ upon said draw
a stock piece to be drawn through said work
head moving to a predetermined position adja
head, an operating member for each of said J'aw
cent said Workhead.
members, mechanical power generating means
carried on said drawhead, linkage means actu
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