US1508790A - Press for cutting or punching sheet material - Google Patents

Description

16 1924' s. c., HILL 8 0 PRESS FOR CUTTING 0R PUNCHING SHEET MATERIAL File d Oct. 18, 1922 Patented Sept. 16, 1924.

A'TENT OFFICE;

enonen o. HILL, or :sosron, MASSACHUSETTS, ASSIGNOR TO REESE SHOE MACHIN- ERY COMPANY, or sos'ron, MASSACHUSETTS, A CORPORATION or MAINE.

PRESS FOB CUTTING OR 'PUNCHING SHEET MATERIAL.

Application filed October 18, 1922. Serial No. 595,373.

To all whom it may concern .1 I

Be it known that I, GEORGE C. HILL,a citizen of the 'United States, residing at Boston,in the county of Sufiolk and State of Massachusetts, have invented certain new and useful Improvementsin'Presses for Cutting or Punching Sheet Material, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to presses for out tin or punching sheet material, more especially to presses of the general type, represented by clicking machines and dinking machines known in the leather and shoe trades, wherein a heavy head or casting is brought down abruptly so as to strike a heavy blow upon a die, which die is laid upon theleather or other sheet material-so as to out the material, the material lying upon a supporting cutting block of substantial area and thickness, which in turn 1s supported upon rigid portions of the machine beneath, the blow of the head upon the die operating to out through the material in a single operation or blow,-the machinecontrol being arranged so as to permit a single blow with each positioning of the die upon the material.

' The object of thepresent invention is to improve the operation of presses of the kind referred to and more particularly to overcome certain difficulties and defects that have long existed in pressesof such kind.

' The operation of the present invention and its particular advantages will. be pointed'out hereinbelow in the detailed description of the invention. To the attainment of such objects and advantages, the present invention consists in the novel press and thenovel features of combination, arrangement and structure herein illustrated 01' described.

In the accompanying drawings Figure 1 is a side elevation of a press'embodying the present invention, the so-called'clicking ma chine being employed for the purposes {of illustration, the operator standingat the left in this figure and shifting the die and controlling the machine, for example,as explained in the prior patent of" A. R. Schoenky Number 1,295,931, patented March at, 1919, fromwhich patent the general feas tures'of the illustrated machine are largely taken.

Figure 2' is a partial perspective view showing an ordinary form of cutting die resting upon sheet material or leather which in turn is resting, upon the cutting block of the machine shown in Figure 1, the present invention being embodie I will first describe some of the well known and general parts of a machine of the class referred to. A four-legged frame 5 gives support to various elements including a heavy and rigidly supported bed or table 6 consisting of a casting, usually made separately and rigidly mounted on the frame. Braces 7, or the like, may be provided to give the bed greater rigiditv or solidity of mounting. Integral with the frame casting 5 are shown at the rear bearings 8 for certain verticallymoving parts, as will be described. i

It is important in machines of this class to provide relative adjustment as between the bed or lower press member and the head or upper press member. This is sometimes secured by vertical adjustment of the bed and the parts supported upon it. An adjusting wheel 9 is shown for this purpose, the details of which may be ascertained from said prior patent. By this adjustment the machine is able to'employ dies of different height or depth, and allowance can be made for Variations in dies due to the sharpening of them and other causes.

. Located at a higher level than the bed is the upper press member-or head 10. In the illustrated embodiment of the invention this the work. In some types of die cutting machines the head is supported at its opposite ends and slides upwardly and downwardly in a fixed path, and the present invention can be applied tosuch machines, but is illustrated as applied to the clicking machine, in which the head or descending pr'esser 10 can be swung to either side so as to be brought over the die in'any position and caused to descend in such position.

The head is shown as provided with a rearward extension 11 which in turnhas a downward extension 12, and these parts are formed with two bearing portions 13, one above the other. The connection of the head to the frame is through the bearings 13, 13 on the head and the bearings 8, 8 on the frame, and an upright cylindricalpillar 14: engaging all the bearings. Conforming with the disclosure in said prior patent, the pillar 1.4 is arranged to slide upwardly and downwardly in the frame bearings 8, while the head bearings 13 are arranged to rot-ate on the pillar; so that the head is capable of the lateral swinging movements as well as the downward and upward operating movements. The particular mechanism for effecting the movements of the pillar forms no part of the present invention and is generally indicated on the drawings by the. reference 15. The mechanism is. driven by power'through a belt pulley 16. The control may be througha lever 17 operated by; a. foot bar or pedal 18; or, as shown, the controlmay be performed by hand through a hand bar 19 connected with the bar 18- by rod 20.

The head is shown in its raised position and it normally stands in this position until operated, and usually upon operation the head makes a single descentand rise.

abrupt blow by the heavy casting 16- gives a very effective cutting action. Beneath the head is shown a die 21 resting upon the leather or other material-22 which liaszbeen spread outupon acutting block 23.v These parts are shown in both figures. The. cutting block is a well known element in such inachines and consists usually of wood, or

at least presents an. upper cutting surface of wood, the grain of the, wood preferably running vertically. The cutting block 23 will be seen to have a flat. upper sintace,

trued to the horizontal as exactly as possible,

and it is of substantial depth, perhapsfive or six inches, sothat it posseses oonsideraable inertia resistance of its: own. Its weight rests upon the heavy bed casting 6.. The material of the cutting block mi-glrt be changed to some other vibrous or analogous material, capable of being somewhat out by the die, rather than injuring the die,v upon an occasion when one of them must suitor.

According to the present invention, I wholly separate'the cutting block 23- from the underlying bed 6 by means of a layer of resilient material 24, for example, a. blanket of live rubber which overlies the bedand supports the cutting block. By this arrangement the cutting block, while firmly held in position, is in a sense floating upon the: layer of resilient rubber and in eilect without any rigid or mechanical connection to the bedbeneath. The block is shown surrounded. by clamping bars 25 which securely consolidate the wood components of the block, and additional clamps or hooks 26 are shown arranged to hold down the clamps 25 and the periphery of the block. The clampingisy'stem, therefore, satisfactorily holds in relae tive position the cutting block, the residient elementand the bed. f

The live rubber layer 214:- beneath. the deep heavy cutting block is not to be coi hised with the use of rubber as a bufier in certain non-analogous arts. It is far'more than a buffer in the present use, and advantages and results are secured which are peculiar to the class of machine tjowhicli this invention is directed. The rubber blanket in fact does notv perform. the function of a buffer in the ordinary sense, for the reason that it is closely between the block 23 and bed 6, both of large area, and the rubber being substantially incompressible, although .tasillu-re of the die to. cut wholly through. the

work with a. single blow of the head, especially with. certain kinds of stock being out,

for example: several. superposed layers. of leather, cardboard, eta, or other heavy or resisting material. It is very disadvantageous to: apply a second. blow or cut in the same cutting operation, because of the possibledamage due to the changed conditions, and because of loss ot time andv output WYi-th the present invention the machine has been made greatlymore. reliable this respect, and it is found that a complete cut can. be .efiected with a single blow where ImequeI-it difiiculty before existed. The character of the work is in this way improved, as.- well. as the output oi the machine. 7 r

. I believe that. an action takes place which may be as follows. The dieis always considerably smaller than the bed and block, and even with a larger die. the actual cutting areas are relatively small. I believe. that a local yielding of the. cutting block takes place, namely, at the cutting area, below the die or the cutting portions of the: die This would. be different from. a generai downward. yielding. of the entire block- The resilient material probably flows .lfl lillfldlafiliBOHl beneath the cutting areas. Therefore, the yield of rubber at these points would invol'fve the. compress ing piling oithesrubbeiat surroundingxpoints. The entire action would been.- tremely but is apparently eflectii're'. The cuttnig block. itself, although of heavy inertia. and. relatively stifi, may bend. mi.- nutely at. the areas of greatest pressure fior it must remembered that the descending head is a heavy casting and delivers very powerful blown. The descrizbed ninute yielding action of the rubber blanket and cutting block'may take. place at about place to the same extent.

the conclusion of the descent of the head. The inertia of the head compels an appreciable pause before it can reverse and rise. During this minute period I believe that the rubber layer and cutting block, which have yielded locally, make an instantaneous return movement, restoring their normal shapes. This sharp, forcible upward move ment constitutes a sort of second or supplementalv pressure, insuring completion of the cutting if it has not been completed. In some cases I have even been able to observe what seems to be a double blow, the main blow of the head and the immediate comeback of the block. These actions it is understood would be caused in a case where the cutting resistance is very great. The machine as constructed by me thus adapts itself to the conditions. The more effective cutting action required by the heavier stock is produced, due to the resistance of the stock. IVhen light, easily cut material rests on the cutting block there Will be no substantial difficulty in effecting the cutting and the described actions will not take Whether the above explanation is fully correct the results have been attained in practice, due to the interposition of the live rubber layer.

Another difficulty in prior machines has been the liability to break the dies, especially if they have been made too sharp or rendered uneven in resharpening, or in cases where the head and bed are not truly square with each other. The ability of the cutting block to yield locally renders it self-adaptable to such conditions and in practice has elfeeted a substantial saving in (lies. A. similar difliculty has existed in cases where a heavy blow is struck upon a die upon irregular stock, the die sometimes having been driven into the material of the block to such an extent as to break the edges of the die in removing it.

For similar reasons the resent invention saves the face of the cutting block against excessive disfiguration. A much finer adjustment is possible and a complete out can be assured without the necessity of driving the die into the material of the block. Substantially, the machine can be adjusted so as to drive the die to but not into the wood surface. This is especially true in cases where a relatively heavy blow is required.

Owing to these factors, a machine may be constructed with a considerably heavier blow-striking head, and harder blows can be struck. These are real advantages in that much greater eliiciency and uniformity of cutting is permitted. The increase of weight of the head and the blow are without added danger to the die and block.

The machine is very substantially freed of excessive noise and jar, Which in a machine lacking the present invention might be very disadvantageous and annoying. The rubber blanket tends to insulate the noise and vibration, and in this way a heavier blow may be delivered With less objection.

It will thus be seen that I have described I a press of the class referred to, which is more efficient and convenient in action, more durable, as regards the .machine, the cutting blockand the dies, more eifective and uniform in the work performed, and delivering better and greater output with less strain on the operator.

Since many matters of design, arrangement, combination and detail may be variously modified without departing from the principles of the present invention, it is not intended to limit the invention to such matters except in so far as specified in the appended claim.

What'is claimed is:

In a clicking machine or power press for dieing out leather or like sheet material by a loose cutting die selectively positioned upon the material, the combination of a hat rigid supporting bed, a cutting block of substantial thickness and weight overlying said bed and adapted to give support to the ma terial to be cut, a layer of resilient material between the bed and block and of an area to wholly underlie and yieldingly support the block, means clamping the block and layer in place upon the bed, a heavy head above the block, means mounting said head at one side only in a manner to swing laterally whereby it may be positioned above signature hereto.

GEORGE C. HILL.

Images