Improvements in Drawing Presses used for Drawing or Raising Sheet Metal Hollow Ware and similar Articles, part of such Improvements being applicable to other Presses.
Year: 1893

page_text: Date of Application, 1st July, 1893
Complete Specification Left, 2nd Apr., 1894-Accepted, 1st Aug., 1894
PROVISIONAL SPECIFICATION.
Improvements in Drawing Presses used for Drawing or Raising
Sheet Metal Hollow Ware and similar Articles, part of such
Improvements being applicable to other Presses.
DANIEL SMITH Junr. Castle Works Raglan Street Wolverhampton Stafford-
shire Mechanical Engineer do hereby declare the nature of this invention to be
as follows:-
The object of this invention is to construct a drawing press for producing such
articles as those named in the title out of sheet metal. Such press to have certain
improvements in the way of a means for holding down the pressure plate, at the
same time relieving the crank of that part of the strain or transferring such strain
to the body or main casting of the machine. Also means for lifting and lowering
the pressure plate in effective unison with the motion of the plunger or forcer
slide.
Also an improvement in the way of a means of preventing the spur or driving
wheel from gauling or locking on the crank shaft used to give motion to the
forcer slide and pressure plate; such locking or gauling between wheel and shaft
being caused by defective lubrication of the parts in contact, frequently leading
to serious accidents by unexpected descent of the slide, sometimes breaking the
machine and unfortunately more frequently cutting off the hands or fingers of the
person working the press.
The machine or press to which it is intended these improvements shall apply
usually consist of a main casting or frame having suitable guides formed within or
on its sides, and within these guides there is caused to reciprocate by a crank
motion a slide usually called the forcer or plunger slide.
On either side of the
crank are cams used generally to operate the pressure. plate. The crank having
the double duty to perform viz. holding down the pressure plate and force down the
plunger or forcer slide. It is the use of the cams and the strain they impose on
the crank shaft that I seek to dispense with and obviate, transfering such strain
from the crank shaft to the body or frame of the machine.
I will now describe the means to hold down and otherwise operate the pressure
plate.
Preferably attached by suitable joint pins to, say four points on the upper side
of the pressure plate I use four swinging or oscillating levers or inverted pendulum
parts; the upper or free ends of such parts are provided with inclines, the incline
on the one part facing the incline on the other part, two of such parts being in
front of the forcer slide and the other two parts behind it. On either side of the
forcer slide are two pins or rollers, so that as the forcer slide descends the pins or
rollers just referred to strike on the inclines and thereby expand the upper or free
ends of the inverted pendulum parts forcing them under suitable rollers or
projections formed preferably on the inner side of the main casting thereby holding
down the pressure plate during the time the forcer slide continues to travel and
draw or raise the article being produced within the dies. As the crank turns its
bottom centre the forcer slide begins to rise withdrawing the punch, the latter
being drawn, suitable slotted links depending from the forcer slide are connected
to the extremity of a short lever preferably formed between each pair of inverted
pendulum parts, but forming part thereof so that immediately the forcer punch is
withdrawn the slotted links previously referred to engage or come in contact with
the levers and pull them upwards thereby withdrawing the upper extremity of the
inverted pendulum parts from under the rollers or projections formed on the main

page_text: casting thereby relieving the pressure plate of the pressure, and since the pendulum
parts are prevented from further motion by the inner edges coming in contact with
each other or against suitable stops, and in consequence the forcer slide continuing
to travel upwards, does, by means of the slotted links lift the pressure plate for
the removal of the article raised or drawn. The rollers or projections previously
referred to as formed on the main casting are provided with suitable means of
adjustment for the purpose of varying the pressure on the pressure plate.
In order to prevent accidents previously referred to, I construct the spur or
other wheel used to rotate the crank shaft with a bush, free to rotate within the
wheel and on the shaft, so that in case the bush should lock itself on to the shaft,
the spur or other wheel would rotate on or around the bush, and by a ratchet on
the periphery of the collar forming part of the bush, the rotation of the spur
wheel without the collar would create a noise by a spring pawl passing over the
ratchet, or by suitable means a bell may be caused to ring, in order to draw
attention to the necessity of lubrication. I may affix a lubricator and so construct
the bush that any resistance to its rotation through insufficient lubrication could
be used to force in grease, and thereby render the lubrication of the shaft and bush
or wheel automatic.
In order to avoid the clutch or stop-motion interfering with the bush, a disc
is used to contain a suitable clutch, this is keyed or otherwise secured to the
crank shaft in such relation to its heavy side, so that the heavy or solid side of
the disc is used to counterbalance the crank and slide. A ring being formed on
the one side (preferably the inner side) of the wheel having suitable internal
recesses into which the clutch within the disc can engage.
This improvement is applicable to all kinds of press wheels that rotate on the
shaft and are engaged thereto by the intervention of any suitable clutch.
Dated this Thirtieth day of June 1893.
DANIEL SMITH, JUNR.
COMPLETE SPECIFICATION.
Improvements in Drawing Presses used for Drawing or Raising
Sheet Metal Hollow Ware and similar Articles, part of such
Improvements being applicable to other Presses.
DANIEL SMITH Junior Castle Iron Works Raglan Street Wolverhampton
Staffordshire Mechanical Engineer do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The object of this invention is to construct a drawing press for producing such
articles as those named in the title out of sheet metal. Such press to have certain
improvements in the way of a means for holding down the pressure plate, at the
same time relieving the crank of that part of the strain or transferring such strain
to the body or main casting of the machine. Also means for lifting and lowering
the pressure plate in effective unison with the motion of the plunger or forcer
slide. Also an improvement in the way of a means of preventing the spur or
driving wheel from gauling or locking on the crank shaft used to give motion to
the forcer slide and pressure plate; such locking or gauling between wheel and
shaft being caused by defective lubrication of the parts in contact, frequently
leading to serious accidents by the unexpected descent of the slide, sometimes
breaking the machine and unfortunately more frequently cutting off the hands or
fingers of the person working the press. The machine or press to which it is
intended these improvements shall apply usually consist of a main casting or
frame having suitable guides formed within or on its sides and within these guides
there is caused to reciprocate by a crank motion a slide usually called the forcer

page_text: or plunger slide. On either side of the crank are cams used generally to operate
the pressure plate. The crank having the doublé duty to perform viz. holding
down the pressure plate and force down the plunger or forcer slide. It is the use
of the cams on either side of the crank that I seek to dispense with and the strain
that is imposed thereupon that I obviate, transferring such strain from the crank
shaft to the body or frame of the machine.
I will now describe the means to hold down and otherwise operate the pressure
plate. Preferably, attached by suitable joint pins to, say four points on the upper
side of the pressure plate I use four swinging or occilating levers or inverted
pendulum parts, the upper or free ends of such parts are provided with inclines,
the incline on the one part facing the incline on the other part, two of such parts
being in front of the forcer slide and the other two parts behind it. On either
side of the forcer slide are two pius or rollers, so that as the forcer slide descends
the pins or rollers just referred to strike on the inclines and thereby expand the
upper or free ends of the inverted pendulum parts forcing them under suitable
rollers or projections formed preferably on the inside of the main casting thereby
holding down the pressure plate during the time the forcer slide continues to travel
and draw or raise the article being produced within the dies. As the crank_turns
its bottom centre the forcer slide begins to rise withdrawing the punch, the latter
being drawn. Suitable slotted links depending from the forcer slide or free
sliding pins baving a head on their upper ends are connected to the extremity of a
short lever preferably formed between each pair of inverted pendulum parts, but
forming part thereof so that immediately the forcer punch is withdrawn the slotted
links or free sliding pins previously referred to engage or come in contact with
the forcer slide and pull the short levers upwards thereby withdrawing the upper
extremity of the inverted pendulum parts from under the rollers or projections
formed on the main casting thereby relieving the pressure plate of the pressure,
and since the pendulum parts are prevented from further motion by the inner
edges coming in contact with each other or against suitable stops and in conse-
quence the forcer slide continuing to travel upwards does by means of the slotted
links or free sliding pins lift the pressure plate for the removal of the article raised
or drawn.
The rollers or projections previously referred to as formed on the main casting
are provided with suitable means of adjustment for the purpose of varying the
pressure on the pressure plate. In order to prevent accidents previously referred
to I construct the spur or other wheel used to rotate the crank shaft with a bush,
free to rotate within the wheel and on the shaft so that in case the bush should
lock itself on to the shaft, the spur or other wheel would rotate on or around the
bush, and by a ratchet on the periphery of the collar forming part of the bush,
the rotation of the spur wheel without the collar would create a noise by a spring
or pawl passing over the ratchet, or by suitable means a bell may be caused to
ring in order to draw attention to the necessity of lubrication. may affix a
lubricator and so construct the bush that any resistance to its rotation through
insufficient lubrication could be used to force in grease, and thereby render the
In order to avoid
lubrication (of the shaft c bush 17 and wheel 2) automatic.
the clutch or stop-motion interfering with the bush, a disc is used to contain a
suitable clutch, this is keyed or otherwise secured to the crank shaft in such
relation to its heavy side, so that the heavy or solid side of the disc is used to
counterbalance the crank and slide. A ring being formed on the one side
(preferably the inner side) of the wheel having suitable internal recesses into
which the clutch within the disc can engage. This improvement is applicable to
all kinds of press wheels that rotate on the shaft and are engaged thereto by the
intervention of any suitable clutch. I will now redescribe this invention having
reference to the accompanying drawings.
The same letters of reference occurring on one or more views denote corre-
sponding parts.
Fig. 1. is a front elevation of the body or frame part of a machine constructed

page_text: according to this invention showing the parts to be hereafter named in their proper
relation to each other when the crank c is at the top of its stroke.
Fig. 2 is a similar view to Fig. 1. only showing the same parts in their proper
relation when the crank c is at the bottom of its stroke.
Fig. 3. is a sectional elevation of Fig. 2. through the broken line a. b. B is the
frame of the machine C is the crank rotating in bearings d. d. W is a ball joint
adjustable connecting rod to connect the forcer slide E with the crank C. The
forcer slide E reciprocates vertically within the guides F as does the pressure
plate H.
The detached views Figs. 7, 8, and 9 will more clearly show the detail of this
arrangement, Fig. 7 being a sectional elevation of an inverted pendulum part I
through the broken line 9 g of Fig. 8. with its free sliding bolt O in elevation
Fig. 8 being a transverse elevation of a pair of inverted pendulum parts I and I¹
with the glands i removed showing also the head p of the bolt O. Fig. 9 is a plan
of the pressure plate showing also a plan of Figs. 7 and 8 in position but having
one pair of I 1 part removed to show the recesses e e.
Within the upper side of the pressure plate H are formed suitable concave
bearings e. e. in which the lower ends of the inverted pendulum parts I & I¹ swing
or partly rotate and being held within such bearings by the dovetail plates i. i,
these going on to the horizontally projecting ends f at the lower parts of I & I¹ and
secured thereon and likewise within the dovetails formed in the pressure plate H
by the set pins or bolts j. j. (see Figs, 1 & 2). The back part I and front part I
constituting a pair (see Figs. 3. 7 & 8) are formed preferably in one piece and
between each is a short lever n preferably with a jaw formed within its extremity,
within this jaw a bolt O is connected, such bolt extending upwards and passing
freely through the slide E (see also Figs. 7 & 8). This is best shown in position
by Fig. 2 and for this purpose both of the right hand pressure brackets m are
omitted. On the upper end of the bolt O is a head p that prevents it from drawing
through the forcer slide E (the corresponding bolt on the left hand side is hidden
by the pressure bracket m and roller carriers S). It is by means of the bolts O
that I connect the pressure plate H. to the forcer slide E.
Having explained this connection I will now proceed to describe the operation of
one stroke of the combined slide E and pressure plate H also the motion of the two
pairs of pendulum parts I & I' showing how they are caused to put pressure on the
pressure plate H. Beginning with Fig. 1. Sheet 1. In this case the crank C is at
the top of its stroke also the slide E and pressure plate H, the latter hanging as it
were or suspended on the bolts O. The weight of the pressure plate H and its
pendulum parts I. I. (the two visible in Figs. 1 & 2) to approach each other, being
prevented from coming in contact by the small rollers t.
Assuming that the press has started or the crank commenced its downward
stroke. The slide E, pressure plate H with its two pairs of pendulum parts I. I.
all descend together. The stroke of the crank C being say 9". The distance
between the pressure plate H at the commencement of its stroke and the top of the
tool bed T. being about 41" so that at about half the stroke of the crank C the
pressure plate H has descended on to the top of the tool bed T, at this point
the motion of the pressure plate H is arrested also the vertical motion of the
pendulum parts I. 1. As the pressure plate H rests on the face of the tool bed T
it will be noticed that the curved part of the pendulum parts I. I. are about level
with the lower side of the rollers s. The slide E continuing to descend carries the
rollers (four in number two back and two front) downward, these operate on the
inclines at the top of the pendulum parts I & I¹ and extend them, forcing the curved
parts of all four of the pendulum parts I & l' under the roller s. this puts
pressure on to the pressure plate H at four points and serves to grip or hold down
the sheet metal blank that may be placed between the dies for the purpose of being
raised by the further descent of the slide E; having done this, the position of the
slide E is now shown by Fig. 2. The crank C having turned its bottom centre
proceeds to its upward stroke taking with it the slide E, and as soon as it has

page_text: withdrawn the forcer punch u out of the work raised, the top of the slide E catches
against the head of the bolts O, this lifts up at the short lever n and withdraws
the curved part of the pendulum parts I & I' Fig. 3 from under the rollers s and
causes the pendulum parts 1 & I (Figs. 1 & 2) to close together (against the
rollers) and since this arrests their motion and thereby causing the slide E in its
continuation of upward travel to raise or take up the pressure plate H into its
original position as shown by Fig. 1. Since the pressure required to be exerted
on the pressure plate H to keep the creases from forming in the metal blank to be
raised is one requiring careful adjustment the rollers s (four in number) are carried
in the carriers $ these pass through the holders m secured to either side of the
machine frame B as shown. The roller carriers S being screwed and fitted with
the nut v bedding against the under side of the bracket m serve to increase or
diminish the pressure on any part around the pressure plate. After this is properly
adjusted the roller carriers S can be locked or screwed in their correct position by
means of the top nuts v. The lower end of the carrier S is also fitted into a sliding
dovetail formed within the lower end of the bracket m to prevent the rollers s
being drawn away from such bracket. In order to steady the vertical motion of
the pressure plate H I prefer to extend same into the guides F as shown at y
Fig. 9.
If it is desired in this arrangement to dispense with the pressure plate H
it is only necessary to remove the joint pin W from the extremity of the short or
central lever N, this disconnects it from the bolt O and allows the entire removal
of the combined pressure plate H and all the pendulum parts I. The bolts O can
also be removed from the slide E by giving each of them one-half turn, this will
allow the narrow way of the head p to correspond with and pass through the slot
holes formed within the slide E shown by broken lines in Fig. 2. There are two
of these bolts O, the left hand one being hidden by the combined carrier and
bracket S and m, but it is also shown connected to its pendulum part I in Figs. 7
& 8 and partly in Fig. 9. The bolt O in the Provisional Specification is mentioned
as a slotted link, this will also suffice. It having a pin passing through the slide E
and through the slot of the link, the length of its slot being rather more than
sufficient for the half stroke of the slide E. As I use the guides F to guide the
pressure plate H by its projections y. y. Fig. 9. it is very important that the latter
be very free, so much so, that its weight will be sufficient to overcome all friction
between it and the guides F so as to ensure the pressure plate H immediately
descending as slide E commences its down stroke; should this not occur, then the
rollers t would catch on the inclines at the top of the parts I & I' and cause it to
descend but it is best to avoid this by the freedom above mentioned. In the
arrangement just described the amount of strain on the crank shaft C to extend
the pendulum parts I. I. and force their curved parts a under the rollers s by the
descent of the rollers t acting on their inclines is very slight indeed, at the same
time it easily transfers practically the entire strain required to hold down the
pressure plate H on to the main casting or frame B of the machine, thereby
dispensing with the use of cams usually used on either side of the crank, such cams
entailing great loss of power and inflicting on the crank shaft the double duty of
holding down the pressure plate and forcing the forcer slide.
In my improved method, after the pressure plate is secured and its load thereby
transferred to the body of the machine, the crank has only to do the work of
forcing down the slide E with its tool u thereby raising the article out of the metal
blank. There is practically little or no tendency for the curved faces a of the
pendulum parts I. I. to escape or recede from under the rollers s such curved
faces being struck from the centre of occilation as at z in Fig. 7. as indicated.
Any tendency for the curved faces to escape or recede would be effectually resisted
by the rollers t passing down the straightface or inside edges of the II parts.
In Figs. 1. 2. & 3 the spur gear, stop motion, friction break and stands etc. are
omitted but these and other details are added and shown in Figs. 4 & 5 in which
1 is a pinion gearing with a spur wheel 2 this rotates freely on the crank shaft C
and has on its inner side an annular ring 5 having several notches 3 cut in its inside

page_text: face such notches 3 being visible in end view Fig. 5. On the crank shaft C is
keyed a disc 4 that has a sliding key 6 forced outwards by springs, on the side of
this key 6 is a roller 7 this rotates within a circular frame 8 that has an eccentric
projection. As the disc 4 is caused to rotate by its key 6. engaging within one of
the notches 3 within the spur wheel 2, the roller 7 catches on the eccentric projec-
tions of the frame 8 and slides the key inwards and there retains it. At this point
the crank C ceases to rotate until it is necessary to restart the press, then pressure
on the treadle 9 or the handle 10 will pull or swing the frame 8 off the roller 7
allowing the springs to push out the key into the first or nearest notch 3 that
passes it as the spur wheel 2 rotates. 13 is a friction break for preventing the
crank C from over-running its top centre. The disc 4 is made heavy on the one
side this is keyed opposite to the crank C in order to balance it and the parts
dependent therefrom. 14 are fast and loose pulleys and 15 is a fly wheel. 16 is
the usual crossbar with hand wheel and screw connected by rods to the pressure
plate H for lifting out the articles after being raised in the tools.
:
I will now describe the means used to prevent the spur wheel 2 from fastening
on the crank shaft C through defective lubrication or for giving notice that such
parts require lubricating.
Having reference to the accompanying drawings. These improvements will be
best understood by Fig. 6. This shows a part sectional elevation of the centre of
the spur wheel 2. C is the crank shaft. 4 is the disc keyed thereon. 17 is a bush
free to rotate on the shaft C and within the spur wheel 2. 20 is a cap secured
to & prevented from turning on the shaft C. 18 is a solid grease lubricator with a
screw cap, the latter being fitted with grease is forced out along the holes or
channels indicated by screwing up the lubricator cap thereby lubricating between
the shaft C and the bush 17. In the boss of the spur wheel 2 is another solid
grease lubricator 25 with its channels as indicated, this serves to grease the surfaces
between the outside of the bush 17 and the inside of the boss of the spur wheel 2.
From this arrangement it will be seen that if the surfaces between the interior of the
bush 17 and the shaft C get dry or insufficiently lubricated or should these two
parts adhere together then the spur wheel 2 would be free to rotate on the exterior
of the bush 17, and in order that it may be known that the bush 17 was adhering
to or lagging on the shaft C I prefer to form a ratchet wheel on the collar of
bush 17 this will be best seen by Fig. 10. On the boss of the spur wheel 2 1 form
a projection 19 to this I affix a spring that engages with the teeth formed on the
bush 17 so that as the spur wheel 2 rotates in advance or faster than the bush 17
the passing of the spring 21 over the teeth will make a noise and thereby draw
attention to the necessity of lubrication. I may also prefer to make the lubrications
between the crank shaft C and the bush 17. Also between the bush 17 and the
wheel 2 automatic. In order to do this I form a dove-tail recess 24 within the
periphery of the collar 17. Into this I insert the block into which is secured
the solid grease lubricator 25, this is held in position by the gland 26 so that by
unscrewing the set pin 27 the gland 26 can be turned aside and the lubricator with-
drawn or removed for refilling. On the internally screwed cap of the lubricator 23
I form a star wheel and on one or more of the arms of the spur wheel 2 I form one
or more projections like the one shown at 28, these catch against the teeth of the
star wheel 23 in case the bush 17 ceases to rotate with the spur wheel 2 (through
want of grease) and screws down the lubricator cap 23 forcing out the lubricant
through the channels 29 and 30 indicated between the contact surfaces of the
bush 17 and crank shaft C also between the contact surfaces of the bush 17 and
spur wheel 2; but to ensure that the crank shaft C and interior of the bush 17
gets the largest share of the lubricant the channel 29 is drilled larger than the
channel 30 that serves to lubricate the interior of the spur wheel and outside
surface of the bush.
The projections 28 on the arms of the spur wheel only extend sufficiently near to
the centre of the crank shaft C to screw down the cap 23 a certain distance, say
sufficient to expel the greater part of the lubricant but not sufficient to jamb down

page_text: forced out by springs and withdrawn from notches within the annular ring 5 of the
spur wheel 2 by the frame 8.
Having now described and ascertained the nature of this invention what I do
claim is as follows:-
―:
1. The use of the inverted pendulum parts I & I' Figs. 1. 2. 3. 7. 8 & 9 in one
piece with the short lever n having inclines or their equivalent in curved surfaces
at their upper ends also curved arcs at æ or near thereto struck from the centre of
occilation or thereabouts each pair of inverted pendulum parts I & I' being
secured to the pressure plate H but free to swing and suspended from the slide E
by the free sliding bolts O having its head at p or its equivalent in the way of a
slotted link or otherwise substantially as herein described and shown for the
purposes set forth.
2. The construction of the inverted pendulum parts I & I' and the short lever n
in one piece as herein described and shown for the purposes of securing the
maximum strength in this part.
3. The formation of the dovetails in the pressure plate for receiving and partly
securing the dovetail parts i within the pressure plate H or equivalent means for
the purpose of securing each pair of inverted pendulum parts I & I¹ within and to
the pressure plate H also the bolts j as herein described and shown having reference
to Figs. 1. 2. 3. 7. 8 & 9.
4. The combination of the parts I & I' and their bolts O, the rollers t and the
two back and two front adjustable roller carriers S as herein described and shown
for the purposes herein stated.
5. The interposition of bush 17 between the interior of the boss of the spur
wheel 2 and the crank shaft C as a means of preventing or minimizing the chance
of the spur wheel 2 from gawling on the crank shaft C Figs. 6 and 10 as herein
described and shown as applied to such presses as those referred to in the title.
6. The ratchet on the collar 17 and spring 21 to engage in same as herein
described and shown having reference to Figs. 6 & 10 for the purposes hereiu
stated.
7. The construction of the spur wheel 2, its annular ring 5 and the bush 17 with
the disc 4. the latter having a sliding key engaging with the annular ring 5 as
herein described and shown having reference to Figs. 6. 7 and 10 for the purpose
of making it possible to introduce the bush 17 without interference of or the
weakening effects of introducing a stop motion within the bush or near to the centre
of the shaft.
8. The means herein described and shown for automatically lubricating the
interior and exterior bush 17, the crank shaft C aud the interior of the boss of
spur wheel 2, having reference to Figs. 6. 11 & 12, having reference to the
accompanying drawings.