US1858192A - Apparatus for pressing leather - Google Patents

Description

May 10, 1932. c. G. SHAW APPARATUS FOR PRESSING LEATHER Filed Feb. 9, 1929 2 Sheets-Sheet l May 10, 1932. C, Q SHAW ,858,192

APPARATUS FOR PRESSING LEATHER Filed Feb. 9, 1929 2 Sheets-Shee 2 Patented May 10, 1932 UNITED STATES CHARLES GEORGE SHAW, OF HUN TSVILLE, ONTARIO, CANADA APPARATUS FOE PRESSING LEATHER Application filed February 9, 1929. Serial No. 338,875.

This invention relates to improvements in apparatus for pressing leather with more particul-ar reference to the pressing of leather of uneven thickness such, for instance, as bends,

crops, sides, bellies and shoulders, and one of the objects of the invention is to provide an improved apparatussuitable for use in the improved process more fully described in my co-pending application filedFebruary 9, 1929, Serial No. 338,876, for Manufacture of leather, and whereby such leather may be compacted by a pure compressive action without rolling thus eliminating the tendency to unduly distort the piece as is the tendency when leather is compactedV by rolling.

A furthery object is to provide an apparatus by which leather may be uniformly compacted throughout to the desired degree without bagging or dishing the leather and also to remove naturally existant tendency towards bagginess in the leather as is aggravated when leather is compacted by rolling.

A further object is `to obtain the desired degree of colnpactness without unduly distending and thinning` the leather and to obtain a uniform compactness throughout the entire piece of leather and also to obtain a compacted leather piece which has a more perfect surface finish than possible of accomplishment by apparatus hitherto used.

A further object is to produce a uniformly compact leather piece which will have a very perfect finish and flat surface on the grain side and to obtain this result simultaneously with the compacting operation.

A further object of the apparatus is to compact such leather to a desired .degree of compactness by subjecting it to a pressing operation without rolling in one operation thus eliminating entirely the rolling of the leather for compacting purposes and accomplishing the entire compacting of the leather in one operation and thus effectinga valuable reduction in production costs both as to labour costs and time involved and saving valuable factory floor space which would otherufise be occupied by more machines and the fewer number of machines required and the confinement of the operation to a much more restricted departn mental area than hitherto, greatly facilitates the routing of leather to and from themachines and makes possible a superior technique in the methods of handling'throughout the department. By the use of the improved apparatus fewer machines are required and each machine has a much greater output.

A further object is to provide an improved form of pad for use in pressing leather which willenable amuch improved article to be j produced in a more expeditious and eicient manner than hitherto.

A further object, is to provide an apparatus in which the product as itcomes from the machine is sheet-ilat. t

The invention consists essentially in the provision of an improved laminated pad for use in conjunction with a press for finishing leather, said pad adapted to contact with the entire surface of a piece being pres-sed or at least with a substantial part of the surface thereof, as opposed,l to rollers hitherto used in compacting leather in which case the roller contacted at any one timewith a very small portion of the surface of the leather piece, all as hereinafter more particularly described, and illustrated in the accompanying drawings in which,

Figure l is a diagrammatic sectional elevation of a press having the invention incorporated therein. j

Figure 2 is a diagrammatic sectional elevation showingthe use of the invention in conjunction with a press in which case a slight modification is illustrated.

Figure 3 is a diagrammatic sectional elevation of a modified form of apparatus in which the pad A is supported upon what maybe termed a balanced anvil block and in this View is shown a lengthwise section of an ordinary steer hide bend. 90

Figure 4 is a detached view of the bend shown in Figure 3.

In the drawings like characters of reference indicate corresponding parts in the four views. 95

The invention is applicable for use in conjunction with a hydraulic press in which the stationary head platen is indicated by the numeral 10 and the movable platen by thenumeral 1l.

lso

According to the present invention an improved pad A is used and is carried upon the lower platen 11. The pad A comprises a laminated structure composed of layers 12 of relatively inelastic and hard material such as spring steel or rawhide alternating with layers 13 of relatively elastic and softer material such as rubber or rubber composition, the layers 12 and 13 being superimposed upon each other to form a laminated pad A. The thickness of the layers would preferably decrease progressively from the bottom face of the pad to the top thereof and the topmost layer of the pad would be one o f the layers 12 which would be quite thin.

The'layers 12 and 13 forming the pad may or may not be secured together as byvulcanizing. If desired also some or all of the layers 13 could be provided with perforations 14 the purpose of which will hereinafter be explained.

Secured to the head platen 10 is a wearing plate 15 which, if desired, could be provided withheating means such as the steam'passages 16.

In Figure 1 the plate 15 is shown equipped with these heat passageways whereas in Figure 2 an unheated plate is shown. Also in Figure 1 the layers 13 of the pad, are shown provided with perforations 14 whereas in Figure 2 these perforations are omitted.

In nishing leather in the improved apparatus the leather piece 117, after having been suitably conditioned, which may be done in any suitable well known way, is placed upon the pad A with the grain side uppermost and the piece is then subjected to pressure Within the press and with the improved apparatus very much higher unit pressure may be successfully used than is possible with rollers as has hitherto been the practice.

Sole leather has hitherto been compacted by rolling and the rollers used are comparatively small and contact with only a very small portion of the surface of the piece and the compacting is carried out by moving the leather piece with respect to the roller and its bed in order to subject the entire surface of the piece to the roller.

When leather is substantially compacted as by rolling the fibres become set together and a tremendous increase is unit pressure over the unit pressure used in the rolling is required in a subsequent pressing operation to reset the fibres so as to remove or correct the faults originally existing and aggravated by the rolling. Y

Further, the use of these rollers tends to produce that which is known to the industry as tender leather and heavy rolling also has a very marked tendency to destroy the fibres. Alsov when compacting leather with these rollers it is impossible to obtain an absolutely uniform degree of compactness throughout the piece.

By the use of the improved apparatus, however, the compacting is accomplished by subjecting the entire, or at least a substantial part of the leather piece, to a pressing operation. The disadvantages consequent upon rolling are avoided and it is found that an exceptionally uniform degree of compactness throughout the piece may be obtained. V

If desired, certain or all of the layers 13 ofthe pad maybe provided with perforations 14 which perforations operate to cause the marginal edges of the topmost layer 12 to curl up slightly and therefore assure a proper and uniform finish upon the piece towards the edges thereof bycreating a greater intensityof pressure along and adjacent to the marginal areas of leather by permitting a certain amount of sag in the center of the pad which causes the edges of the pad extending beyond the leatherpiece to bend upwardly. It is desirable that in order to obtain the desired edge pressures on the piece, the platens and pad should extend beyond these edges.

There is an advantage in having the pad and the plat-ens of the press wider than the piece of leather to be pressed, as that part of the pad which extends beyond the edge of the leather may be used to advantage in the proper pressing of thev marginal areas of the leather. Further as one of the great advantages of the pressing process as against rolling lies in the simultaneouscompaction of a large part of the leather, it follows that the pad and platens should have ample surface area.

A further advantage of perforating certain layers of the pad is that by this means the pad is more durable and will withstand the heavy punishment to which it is subjected in operation much more effectively. Also higher unit pressures may be used for a given thickness of rubber sheet than with an unpere forated sheet.

By heating the wearing plate 15 which contacts with the grain side of the leather, a more perfect finish may be produced than if the plate is not heated, as there is a tendency when this plate is heated to soften the leather on the grain side, with the result that it tends to flow and amore perfect surface finish results.

The plate 15 may, of course, be heated in any suitable way and in Figure 1 it is shown as provided with passages 16 for a heating fluid. rIhe temperature used would be quite low, preferably not over 1400 Fahrenheit for sole leather.

Any practically desirable unit pressures may be readily applied and the unit pressure used will depend upon that necessary to produce the desired results in the finished leather.

In the case of leather having brand marks it is often practically impossible to deal with these when compacted by rolling but with the improved apparatus these pieces may be successfully compacted so that the finished leather may be cut to greater economy as these brand marks when pressed are much less objectionable.

When branded leather is rolled, the roller in passing over the lumpy brand, bumps and hammers upon it and makes this part very horny and hard, aggravating the une'venness in texture of these parts.

In Figure 2 a lump caused by a brand mark is indicated by the numeral 18 and when the piece is being subjected to pressure this brand mark or hump, due to the elasticity of the pad A, will form a depression in the upper layers of the pad which depressions will be carried down through some of the layers and will gradually diminish to zero, as illustrated, and therefore a degree of compactness in the hump 18 more uniform with that of the rest of the piece will be produced and when the piece is removed from the press the hump 18, which is entirely on the. flesh side may be skived off.

This is an important feature since in leather produced by the improved apparatus the entire piece is sheet-like in its flatness and is of desirably uniform compactness and has a level surface and a finish of finer texture so that it may be cut with the minimum of waste or, in other words, there will be fewer waste portions due to the presence of brand marks and such like.

It will, of course, be understood that any desired number of layers may be used in the pad'to suit any particular requirements.

The improved apparatus is suitable for finishing any pieces of leather including bends, crops, bellies, sides, shoulders, or any pieces of leather of substantial area as produced in the tannery.

Referring to F ig. 3 of the drawings, this shows the provision of a balanced anvil block 19 which is provided with a spherical bearing 2O seating in a spherical seat 21 in the platen 11. The pad A is supported upon the anvil block 19 and is positioned thereon so that the center of curvature of the spherical seat is at or near the center of the top surface of the pad and therefore the anvil block and with it the pad is capable of a tilting movement upon the platen 11 in which movement the center point of the top surface of the pad does not move.

In Figure 8 a steer hide bend 22 is shown in lengthwise section being pressed within the press. This bend is of varying thickness, the shoulder portion B being thinner and of looser fibre structure than the kidney portion C. Also the butt tip D may be either thicker or thinner than the portion C.

If a uniform compactness and firmness is to be produced in the finished bend, it is necessary that the unit pressures over the area of the bend be so distributed that the looser fibred lportions be subjected to a greater intensity of unit pressure than the closer fibred portions, and this distribution of'unit pressuresmust be accomplished regardless of the thickness of the respective portions of the bend. This desirable distribution of unit pressures is facilitated by the use of the balanced anvil block 19.

In placing a bend 22 in the apparatus shown in Fig. 3, the operator predetermines those portions of the bend which are to be subjected to greatest and least unit pressures, and by properly positioning the bend on the surface of the pad A with respect to the center point thereof, when the squeeze is exerted, the'anvil block and with it the pad will tilt and due to the principle of levers functioning with the center point of the top surface of the pad as fulcrum, the distribution of unit pressures over the surface of the bend will vary, depending upon the disposition and characteristics of the various local areas of the bend with respect to the center point of the top surface of thel pad.

`In this way by suitably placing the bend as above described, the total load imposed upon the bend may be divided with respect to any straight line passing through the center point of the top surface of the pad so that bythe use of the balanced anvil block described and the resilient pad A the total load is distributed as desired.

From the above it will be apparent that by suitably positioning a bend in the apparatus an infinte variety of loading conditions may be obtained whereby practically any desirable distribution of the total load may be effected to produce the results desired in the finished article, and those parts of the piece which inherently have .undesirably loose fibre structure may be favo-red and subjected to greater intensities of pressure than other areas so that they attain the desired compactness and firmness.

In previous attempts to press pieces of leather of uneven thickness, the greatest mechanical obstacle has been the' tendency of unyielding platens, which are usually flat, to concentrate upon the thicker portions of the piece and as these portions are frequently more or less centrally located, as the kidney portion C in Figs. 8 and 1, the natural result has been that the total load of the apparatus was concentrated on such thicker portions. This concentration on such a portion as the kidney area C is undesirable if uniformity in compactness or firmness of the piece is desired and, as this portion is naturally of more compact fibre structure, it requires very little compaction to suitably firm it.

As a result-of such improper concentration of pressure on these areas, such pieces have been anything but desirably uniform in compactness over the whole piece.

On some parts, such as thick necks, Which naturally are parts of a shoulder and which are of very loose fibre structure this concentrati'on is not undesirable but it is impossible when pressing between unyielding surfaces to so press such pieces that the thinner areas may, if desired, be subjected to equal or increased unit pressures to those in the thicker portions excepting in such case where the cross section of the piece is wedge shaped.

Local lumps such as the brand 18 in Fig. 2 frequently occur in the thicker kidney portions of the bend, still further aggravating the tendency to concentrate pressure on these parts.

Due to the above the pressing of sole leather in such pieces as bends, crops and such like between non-resilient surfaces has been of very questionable value and has been largely discontinued. Further, such pressing operation has been as an auxiliary to the rolling of sole leather, for the reason of its ineffectiveness in producing a desirable commercial product.

The first natural thought is to provide a resilient layer or pad between the flesh side of the leather piece and the unyielding platen surface to compensate for these thicker parts of the leather.

If the fiattening of a piece of rolled leather is to be accomplished in a press, the piece must either be flattened out and kept in this position for a long period of weeks, or unit pressures greatly in eXcess of those used to originallyk set the piece in its baggy shape are required to reset the fibres of the piece so that the piece will remain flat, and these pressures were never hitherto attained nor properly distributed.

rl`he present apparatus is designed to initially set the libres by applying unit pressures equal to or in excess of rolling pressures so that the piece, without any rolling and as a result of the sufficiently high unit pressures applied in the press, assumes as a result of the compacting operation a sheetlike flatness as delivered from the press.

To produce without rolling or other means of substantial compaction, a piece of pressed sole leather of any desired degree of compactness, necessitates the use of such high unit pressures that a pad has to withstand terrific punishment and niy improved pad has great durability and functions in a very efficient manner.

For the top sheet of the pad or the one on which the leather rests, if extremely uniform pressures are required on small local lumps in the leather, rawhide is preferably used on account of its low resistance tobending. This rawhide, however, has been found undesirable in the pressing of sole leather on account of its leaving the flesh side more or less roughened by small pieces of adherent flesh which easily sink into its surface and for the pressing of sole leather a thin tempered spring steel top sheet, surface finished so as not to stain the leather is used, which sheet would be quite thin, preferably not over one-sixteenth of an inch. Such sheet forms a very satisfactory top sheet of my pad in pressing sole leather as it does not cause any serious concentration of pressure on branded areas and such like.

rihe topinost rubber sheet 13 should be the thinnest rubber sheet in the pad because in case of accident, as in the pressing of a doubled over or folded piece of leather, more depression is required in the top sheet than is normally required and if the sheet of rubber immediately beneath the top steel sheet 12 is too thick it will allow the leather to sag into the steel sheet so far as to injure it. If, however, the top layer of rubber is of proper thickness it will so concentrate on these folded portions as to crush the leather at this part and cause little or no damage to the top steel sheet.

The next sheet of steel should also be quite thin and it in its turn is supported upon a quite thin sheet of rubber for the same reason as stated above.

if, however, a brand be concentrated upon such sheets, the first sheet of rubber will distribute part of its displaced volume to the side and likewise the second layer, causing in the second sheet of rubber a shallower depression of larger extent and in this manner throughout the succeeding layers gradually pyramids and nally reduces to zero.

If the second steel sheet is too thick, the top rubber sheet will be damaged and short lived and the concentration upon any vnormal lump will be objectionable.

Such thicker parts asthe kidney area C being` of considerable area easily deflect the thin steel top sheets which oer practically no resistance as the sag is not sharp, but the top rubber sheets being thin are only effective in compensating for small local lumps, such as the brands 18, as an area, even though great intensities of unit pressure are applied thereon, due to the thinness of the sheets builds up a tremendous resistance to lateral movement and such large areas cause practically no lateral displacement of the rubber in the top sheet, which must be practically all compensated for by the succeeding lower rubber layers.

From the foregoing it will be seen that as the distance from the top surface of the pad increases, thicker steel sheets may be used, as, due to the gradual fading out of the deflection, the deflection decreases gradually from top to bottom of the pad and the resistance of these thicker steel sheets to bending is trivial even under the enormous bending moment caused by the compacting load which is transmitted through layer after layer of the pad from the top platen 10 until due to the lateral liet displacement of the rubber sheets it vanishes and becomes simple compression.

An improperly constructed pad will cause a lack of intensity of pressure on the marginal areas of the leather beingpressed and to compensate for this, the steel sheets towards the bottom of the pad are kept as thick as is proportional to the depth of the pad and that part oi' the pad which should extend beyond either edge of the leather being pressed, causes, due to the curling up tendency of these parts, Which in turn is'facilitated by perforating the lower layers of the rubber, concentrations of edge pressure on the leather which edge pressure graduallyvbuilds'up from the bottom to the top layers of the pad.

The Width of the marginal area of the leather over Which the edge pressure is applied Inay be varied-as desired by suitably proportioning the thickness and number of the various steel sheets in the pad and the lateral dimensions of the pad with respect to the size of the leather piece under pressure and the application of this edge pressure is more easily controlled by perforating certain of the rubber layers.

The maximiun thickness Which maybe used for any rubber layer inthe pad, in order that it may not be overstrained, is a function ofV the least diameter of any pressure. area and the intensity lolf unit pressure thereon.

The total number of laminations used in the pad, that is, the overall thickness of the pad, must be sutlicient to permit the required lateral displacement'oi the pad caused Vby those portions of the leather Which are of increased thickness such .as the kidney portion C and the brand 18. This lateral displacement of the rubber must be reduced as far as possible to', a lateral bulging ofthe rubber sheet Without sliding relatively to the steel sheets'because sliding rapidlyl destroys the rubber. Since it is practically impossible to eliminate entirely this sliding at some parts, each vlayer is desirably lubricated With mica or soap stone unless the rubber sheets are vulcanized to the steel sheets. Vulcanization is not .desirable since it would involve the scrapping of the entire rubber portion of the pad in case of an accidental injury to the pad and the occasional renewal of the top layers due to ordinary Wear and tear. Y

A pad Which I have found to give very satisfactory results as Well as long life in pressing sole leather crops and bends usingd pressure intensities of from 3,000 pounds per square inch to 25,000 pounds per square inch has been constructed as follows:

The lateral dimensions of the pad were 36 X 66".

The steel sheets 12` are of highV carbon chrome nickel vanadium alloy steel heattreated to have physical properties of about 27 0,000 pounds ultimate tensile strength;

200,000 pounds elastic limit and 17% elongation.

kThe rubber sheets are of a carbon black zinc o'Xide stock having physical characteristics of about 4,000 pounds ultimate tensile strength and 600% elongation.

The top sheet of steel may be either nickel platedfor painted with suitable lacquersuch as duco auto lacquer and about 3/64 ofan inch thick.

The succeeding layers of the pad counting fromthe top were as follows:

2nd layer of steel le thick.

3rd layer of steel 115' thick.

4th layer of steel l/g thick.

5th layer of "steel /S thick.

6th layer of steel -g thick.

7th layer of steel g thick.

8th layer of steel lf thick.

9th layer of steel fig thick.

10th layer of steel g thick.

1st layer of rubber 55g" thick.

2nd layer of `rubber 1/8 thick.

3rd layer of rubber lgMthick.

4th layer of rubber g thick.

5th layer of rubber g thick.

6th layer ofrubber fg' thick.

7th layer of rubber 'g" thick.

8th layer of rubber g thick forated 10% holes). y Qth'layer of rubber fg perforated y10% holes). 10th layer of rubber ig thick (should be perforated 10% holes). I

The above specificationsfor the pad are intended to illustrate only the construction' of a typical pad VWhich is actuallybeing successfully used for sole leather as above stated in a live thousand ton press, and I do not confine my invention to these particular specifications for the pad. i

Also the pad A may be suitably constructed by substituting rawhide sheets for certain of the steel sheets under Condit-ions Where the use of rawhide may be desirable and the general construction of the pad may be vastlyvaltered as to the physical characteristics vo f its various parts and the thickness and number thereof so as to make it suitable for use in platin presses for upper leather and such ulike an general embossing presses.

While I have illustrated and described they pad as supported by the bottom member of the press which no doubt is the naturalposition, it is Vobvious that the respective'positions of the anvil block 19, pad A and Wearing plate 15may be suitably interchanged. I

From the foregoing it Will be apparent that the invention provides an improved apparatus for pressing leather whereby the objects set'forth have been attained.

As many changes could be made in vvidely different embodiments of the invention, Within the scope of the claims,

(may be pery thick (Should be the Vabove construction and many apparently with a press comprisingvan upper platen andl a lower platen one of which is movable towards and away from the other, and one of which is movable to adjust the angle of its face with respect to the other, of a laminated pad carried by one of the platens.

2. In apparatus for pressing leather and the like at high pressure, the combination with a press comprising an upper platen and a lower platen one of which is movable towards and away from the other, and the face of one of which` is adapted to turn with respect to the face of the other, of a laminated pad carried by Vone of the platens, said pad formed of alternate sheets of material of different degrees of compressibility.

3. In apparatus for pressing leather and the like at high pressure, the combination with a press comprising an upper platen having a polished surface anda lower platen one of which is movable-towards and away from the other,'of a laminated pad carried by one 0f the platens, said pad formed of sheets of relatively incompressible material alternating with immediately adjacent sheets of relatively compressible elastic material and terminating in a facing operating sheet of incompressible material.

4. In apparatus for pressing leather and the like at high pressure, the combination with a press capable of applying intense pressures comprising an upper platen and a lower platen, one of which is movable towards and away from the other, of a laminated pad carried by one of the platens, said pad formed of sheets of relatively incompressible and hard material alternating with immediately adjacent sheets of relatively compressible elastic and soft material'and terminating in Y a facing operating sheet of relatively incompressible material.

5. In apparatus for leather and the like at high pressure, the combination with a press comprising an upper platen and a lower platen one of which is movabletowards and away from the other, of a laminated pad carried by one of the platens, said pad formed of sheets o'f metal alternating with sheets of rubber, the press having sufcient strength to sink leather pressed thereby into the pad and stretch the metal adjoiningthe edges of thel leather about these edges. Y

6. In apparatus for pressing leather and the like at high pressure, the combination with a press comprising an upper platen and a lower platen one of which is movable towhich is polish-ed and plane and the other of which is tiltable around a point near the sur-A face of the platen, of a laminated pad carried by one of the platens, said pad formed of sheets of relatively incompressible and hard material such as steel, rawhide and the like, alternating with immediately adjacent sheets of relatively compressible elastic and soft materials such as rubber, rubber composition and the like and terminating in a facing operating sheet of steel.

7. In apparatus for pressing leather and the like at high pressure, the combination with a press adapted to give intense pressure comprising an upper platen and a lower platen one of which is movable towards and away from the other, of a laminatedl pad carried by one of the platens, said pad formed of alternate sheets of material of 4different degrees of compressibility, and heating means associated with the other platen. r

8. In apparatus for pressing sole leather, the combination with a press comprising an upper platen and a lower platen one of which of an anvil block having ball and socket bear- Y ing with the lower platen, a cushion pad whose operating face is flexible` in all perpendicular planes, supported upon the anvil block, the Vcenter of curvature of the ball and socket bearing being located approximately at the center point of the top surface of the pad.r

10. A pad for use in pressing'leather at high pressure comprising a plurality of sheets of material of different thicknesses progressively thickening from the operating face of the pad toward the back thereof and beginning at the operating face of the pad.

l1. In a pad for use in pressing leather at high pressures, a highly resilient sheet of lling material having a'plurality of perforations each small as compared with the size of the sheet and two restraining metallic sheets,

one on each side of and against'the resilient sheet. Y

12. In apparatus for pressing leather and the like at high pressure, the combination withl a press comprising an upper platen and a lower platen one of which is movable toward the other and a pad comprising a sheet of spring steel adapted to engage the leather press and larger in area than the sheet to be pressed and wards and away from the other, andone o f a compressible resilient packing for the steel Dit las

whereby in operation of the press the edges of the steel are tightened against the leather sheet by the relative cupping of the steel, whereby additional pressure is applied to the edges of the sheet pressed by reason of the cupping of the steel.

13. In apparatus for pressing leather and the like at high pressure, the. combination with a press comprising an upper platen and a lower platen one of which is movable toward the other and one of which has a polished surface, and a compressible resilient pad for the press having a cushion between which and the polished surface the leather is pressed.

4. In apparatus for pressing leather and the like at high pressure, the combination with a press comprising an upper platen and a lower platen one of which is movable toward the other and one of which has a polished surface and a resilient pad for the press having a cushion between which and the polished surface the leather is pressed, the resilient pad being made up of a plurality of alternating sheets of relatively resilient and relatively non-resilient materials of increasing thickness as the distance from the face of the pad increases whereby the depth of compressible resilient support for the leather pressed becomes much greater than the distance in thickness of leather in the area` compressed.

l5. A pad for pressing leather at high pressure having a metal operating face and alternate perforated rubber and sheet metal supporting packing immediately adjoining it whereby the leather is resiliently engaged by the metallic face of the pad and is pressed into the face flexibly in all planes perpendicular to the leather during the pressing operation and the sagging of the leather into the face of the pad causes marginal pressure upon the leather by the adjoining surface of the support.

1G. A pad for use in pressing leather at high pressure comprising a facing operating sheet of steel and adjoining alternate sheets of compressible material and steel, the thickness of the steel being graded from the face of the pad toward the opposite face thereof.

17. A pad for use in pressing leather at high pressure comprising parallel alternating and adjoining sheets of relatively incom pressible material and rubber terminating in a facing operating sheet of incompressible material.

18. A pad for use in pressing leather at high pressure comprising a facing operating sheet of spring steel and an adjoining sheet of rubber.

19. A pad for use in pressing leather at high pressure comprising a plurality of sheets of material of relatively high tensile strength and low compressibility alternating with sheets of material of relatively low tensile strength and high compressibility and terminating in a facing operating sheet of relatively high tensile strength and low compressibility.

20. A pad for use in pressing leather at high pressure comprising alternating sheets of material of different degrees of compressi bility, the thickness of said sheets of both ma-v terials progressively decreasing from one face of the pad to the other and terminating in a facing operating sheet.

2l. A pad for'pr'essing leather comprising alternating sheets of steel and 'of elastic conipressible material, the elastic compressibleA material being perforated.

22. A pad for use in pressing leather at high pressure comprising sheets of relatively incompressible material alternating with parallel sheets of relatively compressible elastic material, the thickness of the lsaid sheets progressively decreasing toward the face of the pad, terminating in a relatively incompressible facing operating sheet and some of said sheets being perforated.

23. A pad for use in pressing leather at high pressure comprising parallel sheets of relatively incompressible material alternating with sheets of relatively compressible elastic material and some of said sheets of greater compressibility being perforated.

24. A pad for use in pressing leather comprising sheets of steel alternating with adjoining sheets of rubber and terminating in an operating facing sheet of steel.

25. In apparatus for pressing leather and the like at high pressure, the combination of a press capable of exerting a pressure in eX- cess of 1000 pounds per square inch upon a product to be pressed therein and comprising an upper platen and a lower platen, one of which is movable toward and away from the other, of a laminated pad carried by one of the platens, said pad formed of sheets of spring steel alternating with sheets of rubber, the rubber being thin enough to avoid lateral expression under the pressures indicated, and the alternation of sheets terminating in a facing operating sheet of steel.

26. In apparatus for pressing sole leather, the combination with a press comprising an upper platen and a lower platen, one of which is movable toward and away from the other, of an anvil having ball and socket bearings with one of the platens, centering near the surface of the platen and a cushion pad come prising a facing operating sheet of hard material and immediately adjoining successive sheets of alternating soft material and hard material.

27. A pad for use in pressing leather at high pressure comprising alternate sheets of steel and adjoining compressible elastic material, the thickness of the compressible elastic material being graded from thev surface of the pad toward the opposite surface thereaci ice

of and the final surface being an operating surface.

28. A pad filling material for use in presses and comprising a highly eompressible resilient sheet having a number of spaced perforations each small as compared with the size of the sheet.

Y 29. In apparatus for pressing leather and the like, the combination with a press coniprising an upper platen and a lower platen, one of which is movable toward the other and one of which is heated and has a polished surface, means for heating the surface,V and a compressible resilient pad for the press having a cushion between which and the polished surface the leather is pressed.

In witness whereof I have hereunto set my hand. Y

CHARLES GEORGE SHAW.

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