US1744756A - Leather stretching and tacking machine - Google Patents

Description

Jan. 28, 1930. w. A. ELLISON LEATHER STRETCHI NG AND TACKING MACHINE 5 Sheets-Sheet 3 Filed April 15, 1927 Jan. 28, 1930; w. A. ELLISON 1,744,756

LEATHER STRETCHING AND TACKING MACHINE Filed April 13, 1927 5 Sheets-Sheet 4 I66 a I56 260 2H Jan. 28, 1930. w. A. ELLISON LEATHER STRETOHING AND TACKING MACHINE Filed April 15. 1927 5 Sheets$heet 5 mm mm 3 w u w v p. w 6 I my. MM o M T 9 v J l}! u a E .wdw w 8 w B v F w a; u m

Patented Jan. 28, 1930 UNITED STATES P TENT OFFICE WILLIAM A. ELLISON, 0F SALEM, MASSACHUSETTS, ASSIGNOR TO THE TURNER TAN- NING MACHINERY COMPANY, OF PORTLAND, MAINE, A CORPORATION OF MAINE LEATHER STRETCHING AND TACKING MACHINE Application filed April 13,

This invention relates to the stretching of hides, skins and pieces of leather and to their maintenance in stretched condition. The invention is illustrated as embodied in a machine for stretching skins and other relatively light pieces of leather and for tacking them in stretched condition upon suitable frames or stretcher boards. It is to be understood,

however, that the invention and various imsubsequently to distend the frame to put the piece of leather under tension where it is left until dry. These operations are laborious and require the exercise of very considerable skill'for the reason that the various parts of a skin must be stretched by hand before tacking and the different parts must be stretched different amounts and in different directions according to the characteristics of the material which vary considerably in the difierent parts o-feach skin or other piece of leather. Furthermore, the stretching is car'- ried' out mostly with one hand While the other hand is' used to position and drive the tacks in the material maintained in stretched condition by the first hand. While it may not be necessary to doso, it is a fact that most of the workers use their mouths as a magazine for the tacks, since it enables them to accomplish more work, perhaps because the tongue and lips may be employed in separating and successively positioning the tacks so as to be readily grasped by the hand. Because of these conditions it is becoming increasinglydifficult to obtain workers to perform stretching and tacking operations and wages are correspondingly high. Moreover, in certain factories where it is desired to stretch skins and other like pieces of leather and maintain them in stretched position until they have dried, a well-known method consists in dipping each skin in a recepacle containinga gluey liquid, spreading-it upon a stretcher board, and then smoothing and stretching it 1927. Serial No. 183,501.

out in all directions from a central portion of the skin by. means of a manually operated slicker blade which removes the excess liquid and leaves the skin in a-stretched, smoothedout condition upon the board. If the work has been properly done-the skin will remainadhering to the board in stretched condition until it dries. This method involves an even greater amount of laborious and disagreeable work than that inherent in the first-described method .of stretching and tacking. Moreover, inboth casesa great deal depends upon the worker, his skill and his endurance. Both the quantity and the quality of the work produced by each individual workman varies from day today.

It is an object of this invention to provide skin stretching and tacking means for performing mechanically what has hitherto been accomplished only by hand, with the idea of securing increased production, raising the standard of qualityand, particularly, se-

curing a high degree of uniformity in the product.

To these ends and in accordance with an important feature of the invention, as herein illustrated, means is provided for stretching portions of a skin or other piece of leather from a central portion thereof outwardly toward its edges in the operation of which a predetermined tension developed in .each given portion of the skin will determine the limit of the stretching operation for said given portion. Conveniently, a plurality of stretching devices are employed arranged for movement toward opposite edge portions of a piece of work and having gripper means for engaging edge portions of the piece of work, the arrangement being such that the stretching devices are thereafter moved si multaneously away from each other on opposite sides of the plece of work to stretch the piece simultaneously in all directionsfrom a central portion thereof, securing means being provided controlled by the gripper means so as to secure the different stretched portions to a board or stretcher frame when a predetermined tension has been reached in the portion of the skin gripped by each individual gripper means. Preferably, and as illusof the feeler and the piece of work.

As illustrated, the means for securing the skin in stretched condition comprises a tacker mechanism associated with each stretching device and arranged to be'controlled by the gripper means so that the tacker operates when a certain tension has been reached in the portion of the skin gripped by the gripper means. Conveniently the tacker has conmotions with its associated gripper to cause the latter to release the work at the instant the tack is driven. In the illustrated construction each tacker mechanism comprises a spring operated driver adapted to be locked in raised position with the driving spring under tension, connections being provided between the gripper means and the locking means for thetack driver arranged to trip the locking means when a predetermined tension is reached in the portion of the piece of work gripped by the gripper means.

Other features of the invention: relate to improved means for depositing a tack in the tacker mechanism wherein the tack depositing means is controlled by the movement of the combined stretching and tacking unit. Preferably too, and as shown, a movable chute or delivery tube is mounted for oscillation between a positionwhere it supports a-tack' to a position for'delivering the tack to a tack supporting throat in lme with the driver of the tacking mechanism.

Still another feature of the invention relates to.an improved table or work support mechanism arranged to move the. table or work support to work presenting position with respect to the stretching and tacking devicesthrough operation of the means employed for starting the. machine into operation.

These and other features will be described in detail in the specification and pointed out more particularly in the appended claims.

In the drawings: c

Fig. 1 is a view in side elevation illustrating one embodiment of the invention, that ,part of the figure to-the right of line A being designed to show supporting arms andtack chutes and other parts in side elevational view, while to the left of the line A parts have been broken away and other parts omittedto show a single supporting arm and a stretchof the invention ing and tacking device together with part of the operating means therefor;

Fig. 2 is a detail view showing the work supporting table ofthe machine in lowered position;

Fig. 3 is a view of the table .operating means taken along the line IIIIII of Fig. 2, looking in the direction of the arrows;

Fig. 4 is a sectional View through the raceway operating means showing the controlling clutch therefor in inoperative position; I Fig. 5 is a view similar to Fig. 4 with the clutch engaged;

Fig. 6 is a sectlonal view of the raceway driving means showing additional details including the primary driving shaft;

Fig. 7 is a detail view of the tack separating and tack delivering means;

Figs. 8 and 9 are detail views looking at the lower end of the raceway from above and illustrating the separation of a tack and its delivery to the upper end of a stationary chute;

Fig. 10 is a. detail view taken along the line XX of Fig. 7 looking in the direction of the arrows;

Fig. 11 is a detail view of a portion of a movable chute member;

Fig. 12 is a view in side elevation of one of the stretching and tacking devices on a larger scale than that of Fig. 1 and showing also a partof a similar device on the other side of the center of the machine together with the driving means for both devices, the driving means being in inoperative position; Fig. 13 is a detail View of the driving means for the devices similar to the showing of said means in Fig. 12 but with the driving means in operative position, parts to the left of line B being in side elevation while to the right the parts are in section with the exception of shaft 260 of which the curved surface is shown;

.Fig. 14 is a view similar to Fig. 13 showing the driving means for one device in inoperative position while the other is still operative;

- Fig. 15 is a detail view in side elevation and partly in section disclosing partof the controlling means for the driving means of each stretching and tacking device or un1t;

Fig. 16 is a view similar to Fig. '13 with the driving means of both devices operative for returning the devices along divergent paths to their initial positions ofrest;

17 is a detail view taken along the line XVIIXVII of Fig. 15, looking in the 1 direction of the arrows;

' Fig. 18 is a view of a stretching and tacking device or unit in sideelevation and part- 1y in section while the unit is moving toward the center of the'inachine;

Fig. 19 is a similar view while the unit is moving away from the center of the machine, the tack driver locked in raised position;

45 pressed latch 54 to hold the table 30 in raised Fig. 20 is a view similar to' Fig. 19 just after the driver has been tripped to drive a tack;

Fig. 21 is a plan view of the tack supporting jaws of the tacking mechanism looking from below;

Fig. 22 is a detail view of a gripper member of the work gripping means associated with eailh stretching and tacking device or unit; an

Fig. 23 is a detail view ofpart of the individual driving means for each stretching and tacking device or unit.

In the machine illustrated in the drawings for stretching and tacking hides, skins or leather pieces, a table 30 (Figs. 1 and 2) is provided for supporting a board 32 and a piece of work W while it is being stretched and tacked in stretched condition to the board. It is to be understood that a plurality of boards similar to that shown at 32 will be provided with each machine and that each board will be of a size to accommodate is provided a pair of levers, lever being pivoted between brackets 42 securely attached to standards 36 and having at its free end a weight 44 (Fig. 1) for a purpose that will be presently described. The other lever 46 is carried by a pivot 48 (Fig. 3) supported in brackets 50, 51 extending toward each other from the other pair of standards 36. At its free end the lever 46 carries a pin 52 (Fig. 1) adapted to be engaged by a spring work-presenting position. When it is desired to release the table so that it may drop to work receiving position the operator operates the latch 54 by stepping on a treadle portion 56 thereof, a spring 58 being provided for returning the latch to operative position as soon as it is released by the operator. At their inner ends the levers 40 and 46 are pivotally connected to each other and to a link 60 by a pivot pin 62, the link 60 being pivotally'secured at 64 to a bracket 66 extending downwardly from the central portion of the under surface of the table30, the parts being so proportioned that the table is in elevated work presenting position when the lever 46 is held in latched position by the latch.54. Upon releasing the latch 54, the table at once drops by its own weight to work-receiving position, as indlcated 111 Fig.

2, the weight 44 on lever 40 serving as a counterbalance to offset a great part of the weight of the table, thus permitting the table to descend without an undesirable amount 'of noise and vibration in operating the machine.

senting or operative position there is provided a lever 68 (Fig. 1) pivoted to bracket 51 (Fig. 3) and having a roll 70 for contacting with the free end of the lever 46 to depress the-same upon downward movement For raising the table to work-preof the lever 68 until the pin 52 is engaged under the latch 54, the operating lever 68 having a handle portion 72 adapted to be grasped by the operator for manipulating the operating lever 68 to cause upward movement of the table 30. It is to be understood that the pin 52 will be caused to ride down the slanting surface 74 on the latch 54, thereby causing rocking of the latch 54 to the right in Fig. 1 until the pin is properly engaged by the latch.

For stretching a skin or other piece of work supported on theboard 32 there is provided a plurality. of stretching mechanisms, each of which has'associated therewith a tacker mechanism for securing a portion of the skin in stretched condition, the stretching mechanism,and -the tacker together constituting a stretching and tacking device or unit, indicated generally by the numeral 78, of which there are fifty in the illustrated machine, it being understood that the number may be varied to suit conditions imposed by different classes of work. Each unit 78 is guided and indirectly supported by a supporting arm 80 (Figs. 1 and 12) detachably secured to a circular frame member 82 in turn supported by bars, one of which is shown at 84 in Fig. 1 of the drawings, securely attached to an upright frame member 86, the said bars 84 serving also as supporting arms like the arms 80, each bar and each arm supporting one of the units 78.

Since each of the stretching and tacking units is like every other unit, a description of one will suffice for all. Referring particularly to Figs. 12 and 18 of the drawings it will be observed that each unit 7 8 comprises an L-shaped frame member 90, the upright part.

of the frame member being slotted at 92 (Fig. '18) to receive a sleeve member 94 which is interiorly screw-threaded for co-operation' with a correspondingly exteriorly screwthreaded shaft 96. Preferably, andfas shown, the sleeve 94 is mounted for vertical sliding mov ment within the slot 92 and for this purpose the sleeve 94 is provided with a pair of studs 98 on each side of the sleeve receivable in vertical slots 100 in the frame member 90. By reason of this pin and slot arrangement the frame 90 may adjust itself vertically to suit different thicknesses of work and to suit different positions of the board 32, since it iscontemplated that the board 32 may carry a skin or other piece of leather on each side thereof so that after one skin has been at tached the board may be turned over to have a second skin attached and in its second position it will present a surface higher above the table 30 than in its preceding position. Upon reference to Figs. 12 and 18, it will be observed that the frame 90 has its upper end forked as at 91 to embrace slidably one of the arms 80 (or corresponding bar 84) thereby maintaining frame 90 upright as it is being moved by shaft 96, the entire weight of the unit 78 being carried (when the table 30 is in lowered position) by the shaft 96 which is supported by a bar 84 or an arm 80 in a manner presently to be described;

At the lower front end of the L-shaped frame member 90 there is provided a gripper member 102 adapted to co-operate witha pair of relatively thin-edged gripper rollers 104 (Fig. 21) carried at the lower end of a lever 106 pivoted at 108 to the frame 90. Each gripper member 102 has a number of relatively sharp ridges or corrugations 103 (Figs. 18 and 22) adapted to engage firmly the edge of apiece of work when the latter is gripped between the member 102.and the rollers 104. It will be observed upon inspection of Fig. 19 that when the gripper jaw 102 is in gripping position with respect to the rollers 104 the teeth or corrugations 103 are in front of or beyond a plane passing vertically through the centers of the rollers 104. Hence, any tendency of the rollers 104 to release the work by rotative movement is counteracted by an increased gripping of the curved surface of the rollers engaging with the adjacent corrugations, the result being that the work is securely gripped durin the stretching operation and only released through operation of the gripper member or jaw 102, at the instant a tack is driven, as will be hereinafter described. In order that the gripper jaw 102 may not interfere with the driving of a tack into the work while the latter is held by the gripper, the said jaw is provided with a slot 103* extending into the jaw sufficiently to permit a tack being driven while the aw.1s

. in gripping position as shown in Fig. 19.

5 pin 119 secured to the It will be observed that the gripper mem-- her 102 is pivoted at 105 to an arm 107 of-a lever 109 pivoted at 110 to the lever 106. Connected to the pivot pins at 105, 110 is a link 111 serving with the arm 107 to form a fork for embracing the gripper member 102 and providing the pivot support 105. Lever 109 is connected by'means of a link 112 to a lever 113 pivoted at 115 to the frame 90 of 1ts stretching and tacking unit 78. As will-be hereinafter described the lever 113 operates the tack driver of a tacking mechanism which is associated with each stretching mechanism. Preferably, and as shown, the upper end of the link 112 is slotted as at 117 to receive a lever 113 (Figs. 7 and through an opening in a bracket member 120 secured to frame 90, a light spring 122 being interposed between the bracket 120 and a shoulder 124 at the pivoted end of the rod 118. As shown, the spring 122 is coiled upon the rod 118 and serves to hold the gripper member- 102 in operative relation with respect to the gripper rollers 104. When an edge portion of the work is encountered during movement of the unit 78 toward an edge portion of the work, the gripper rollers ride up over the edge before the gripper member 102 engages the work since the rollers during this movement of the stretching and tacking unit 78 are in advance of the gripper member 102. Hence, by the time that the gripper member 102 reaches the work, the edge ofthe latter is held down firmly by the rollers 104 on the supporting board 32. Upon contacting with the firmly pressed work, yields against its spring 122, thus performing an' important function. as will presently be described. This retraction of the member 102 through its engagement with the stationary edge of the work causes tipping of the member 102 about its pivot 105 with the result sure its engagement under the edge of the work. This engagement readily takes place during the further movement of the unit 78 in the direction to engage the Work, since during'this time the rollers leave the extreme edge portion of the work and press firmly on the work always in advance of the forward edge of the member 102 so that the work is free to be lifted by the forward edge of the latter which is engaged as described quite firmly with the supporting board 32. Upon movement of the stretching and tacking unit 78 in the opposite direction the edge portion of the piece of work is even more firmly gripped-than before, member 102 being aided -in itsgripping movement by the spring 122 and by the pressure of the rollers 104 which press the edge port-ions of the work against the sharp ridges or teeth 103 on the gripper the member 102- which at the time is held down firmly by the over-riding rollers 104 the member 102 is retarded sufficiently to swing its pro ecting end i 126 in an upward direction thereby swinging a lever 128 about its pivot 130 by reason of a pin and slot connection 132, 134 between the part 126 and the lever 128. The swinging of the lever 128 in the direction indicated pulls downwardly upon a rod 136, thereby yieldingly pulling upon a pawl 138 pivoted at 140 .to the frame member 90. In this way the 12') carried by a stationary bracket 150 secure 1y attached to a larger bracket or post 152 projecting downwardly from the bar 84 or f om one of the arms 80. \Vhen the gripper member 102 engages with an edge of the work and has its end retarded thereby as just described, it causes the pawl 138 to engage with the tooth 142 on the bar 144 and hence the bar 144 is moved along with the unit 7 8 until a latch 154 (Figs. 12 and 15) strikes against the lower end of a trip lever 156. When this occurs the trip lever is caused, to swing about its pivot 158 (Figs. 15 and 17 thereby withdrawing its latching end 160 away from a shoulder 162 on an adjustable latch member 164 adjustably secured to a carrier 166. When the carrier 166 is thus released itslides upwardly on supporting post 152 being con.- nected thereto by studs 167 on the carrier movable in slots 169, in the post 152, a spring or springs 168 being provided to effect in a promptmanner such upward movement of' the carrier, and in this way-the shaft 96 has its pinioned end 170 (Fig. 12) lifted away from a large bevel gear wheel 172, thereby terminating rotative movements of the shaft 96 and bringing the unit 78 to a stop. In thisway the gripper member 102 serves also as a feelerfor contacting withthe work and 'de termining the extent ofiinward movement of each of the units 7 8. From this viewpoint the gripper member 102 may be regarded as a feeler for the work which is controlled by the work to initiatedisconnection of the unit 78" from itsmoving means. Since the piece of work, espec ally if it be an untrimmed skm, is very irregular in contour, it follows that the diiferent stretching and tacking units 78 will travel different distances, although all start at the same distance from the center of the machine, so that it is the work which, as a matter of fact, controls the amount of travel of each unit 78 in its movement to engage the nearest edge portion of the work. After all of the units 7 8 have come to rest through tripping of each individual operating shaft 96, all of these shafts 96 are simultaneously reconnected to the largebevel gear 172 which, at this time, is rotating in the reverse direction so that all of the units 78 are caused to move away from the center of the machine along divergent paths to stretch the skin or other piece of work simultaneously in all directions. Thls reverse driving means in this figure being shown locked in raised position by means of a lock 186 slidable in a guideway 188 .in the side of the casing 180 to engage with one of the teeth 190 on the adjacent side of the driver bar 182. The, outer end of the lock 186 passes through a'forked projection 192 on the lever 106, the lock 186 being pressed against the driver bar 182 by means-of a spring 194, the lock 186 being provided with a ball stop 196 engaged in a socket provided in the forked projection 192.

The lever 106 is held normally in such a position by a spring 198 that the spring 194 may be operative to hold the lock 186 with its operative end engaging one of the teeth 190 on the driver bar 182, a shoulder for limiting the movement of the lever 106 by the spring 198 being provided by a projection 200 on the frame 90. When the pull on the gripper member 102 and grip rollers 104,

exerted by the gripped portion of the work during. movement of the unit 78 away from the center of the machine, becomes great enough to overcome the tension of the spring 198 the latter yields in which case the gripper member 102 and the grip rollers 104 are retarded in their movement so that they lag behind the movement of the unit? 8, thereby swinging the lever 106 on its pivot 108 and causing movement 'of the lock 186 to withdraw its operative end from engagement with the selected tooth on the driver bar 182. The latter is instantly forced down by its driving springto drive a tack. Hence, just an instantbefore the gripping means, comprising the gripper member 102 and the grip rollers 104, lets go of the work a tack is driven into the edge portion thereof to hold'it in stretched condition. It will be readily understood that the tension of the spring 198 is an important factor-in determining the amount of stretch to be given to the portion of the work gripped by the .unit of which this spring is a part. As already explained, the gripping means, comprising the gripper member 102 and the gripper ro1ls104, hangs on to the work until the spring 198 yields s'ufliciently to trip the driver ,bar 182. -VVhen this occurs the driver lever 113 instantly forces the driver bar 182 downwardly in a tack driving operation and at the same time the gripper member 102, is retracted to release the work. It follows that if thetension of the spring 198 be increased by adjustment of the adjusting screw 199 (Fig. 18) the greater the tension on the gripped portion of the work will be before it is released. Hence, the amount of stretching of each given portion of the skin and for various classes of skins may be regulated by properly adjusting the tension of the various. springs 198 in the "stretching and tacking units 78. This tension on the spring 198 of a unit which is to engage the butt end of a skin will probably be somewhat greater than the tension of the spring 198 in a unit which is to engage the more yielding flank portions of the skin. This, however, is a matter which comes within the province of the operator who should be skilled in judging the stretching qualities of the skins in the batch to be operated upon in any given working day. In order to insure that the work will be freed from the grip of the'gripping member 102 and the gripper rollers 104, connections are provided between the driver lever 113 and the gripper member 102 by means of the link 112 connecting the driver lever 113 and the lever 109 to which the gripper member 102 is pivoted as has already been described. When the driver bar is approaching its lowest position the pin 119 carried by the lever 113 contacts with the wall at the lower end of the slot 117, thereby forcing the link 112 downwardly and rocking the lever 109 on its pivot point 110 to withdraw the gripper member 102 in an upward and rearward direction, thus freeing the work. Upon reference to igs. 12 and 18 it will be seen that a spring 204 connected at its upper end to a pin 206 secured to the frame member 90 and at its lower end to a pin 208 fixedly secured to the lever 113 pivoted at 115 on the frame member 90 serves as the driving spring for the driver bar 182 and driver 184, since one end of the lever 113 is connected to the upper end of the driver bar 182 by means of a pin 214 on the driver bar engaged in a slot 216 (Fig. 12)

in the end of the lever 113. \Vhen the stretching and tacking unit 78 is approaching the limit of its stretching movement away from the center of the machine, a roll 218 (Fig. 12) on the free end of the lever 113 engages with a downwardly projecting end 220 (Fig. 1) of one of the arms 80 (or with the standard 86 in case of a unit guided on bar 84) so that during the latter part of the described movement of the unit the lever 113 has its roll carrying end depressed, thus putting the spring 204 under tension and elevating the driver bar 182 to its highest position in which position it is locked by the lock 186.

The tacker mechanism which forms part of the unit 78 also comprises a tack supporting means for holding the tack in position beneath the driver, the said means comprising a throat or pocket 222 open at its upper end through which the tack is dropped by means which will hereinafter be described. The bottom of the pocket 222 is made up of two members 224, 226 (Figs. 18 and 21). Of.

source applied to 21 thesemember 224 is pivoted by a vertical pin 228 to a portion of the frame 90 while the other member 226 is integral with the adjacent portion of the frame 90. As shown, the pivoted member 224 is held yieldingly against a vertical edge of the member 226 by means of a curved leaf spring 230, the forward end of member 226 having a slot at 232 to permitescape of the shank of the driven tack. At the bottom of the cup 233 formed in the members 224, 226 is a small opening 234 located in member 224 the tack, the opening 234 being, however, insufiicient in size to permit the tack to drop down with its shank in the opening. When the driver 184 is projected downwardly, the force of the blow drives the tack through the opening 234, spreading apart the members 224, 226. As the unit 78 continues to'travel after the driving of a'tack, the members 224, 226 separate sufficiently to escape from "the driven tack, the head of the tack passing through an opening 236 in the side of the pocket 222, as most clearly shown in Fig. 18.

As has already been stated each stretching and tacking unit 78 is moved in reverse directions by one of a plurality of shafts 96. As shown most clearly in Figs. 1 and 12, each shaft 96 is pivotally supported at one end by means of a bearing 239 pivoted at 240 to a bracket 242 fixedly attached to the standard 86 or (where the arms 80 are secured only to the hub 82) to an upright portion 220 (Fig. 1) of one of the arms 80. At its other end the shaft 96 is supported in a bearing 244 (Fig. 15) furnished by the carrier 166.

. When the carrier 166 is in raised position the pinioned end 170 (Fig. 12) of the shaft 96 is lifted away from the large bevel gear 172. In other words, the shaft 96 is then in idle or inoperative position. On the other hand,

for receiving the small of when the carrier 166 is forced downwardly until it is engaged by the latch 156, the shaft 96 is brought into engagement at its pinioned end 170 with large bevel gear 172 and thus becomes operative by its rotation to cause movement of the stretching and tacking unit 78. The means by which, in the illustrated construction, the shafts 96 are caused to rotate first in one direction and then in the reverse direction will now be described. Referring again to Fig. 1 of the drawings, it will be seen that a main shaft 250 is provided adapted to receive power from any suitable the shaft. At its other end the shaft 250 is provided with a bevel pinion 254 which is adapted to mesh with either one of two relatively large bevel gears 256, 258, both of which are keyed to slide axially on and rotate with a vertical shaft 260 (Fig. 12) mounted for rotation in bearings 262, 264 provided in the frame of the machine. Secured fixedly to the lower end of the shaft 260 by a key 261 (Fig. 13) the large bevel gear 172 alpulley 252 atone end of ready mentioned as the driving means for the shafts 96. Surrounding theshaft 260 within the bearing 264 is a sleeve 266 having a portion projecting below the bearing 264 to which is secured a disk 270 (Figs. 12 and 13), the disk being mounted so that it does not turn with the shaft 260 although it moves with the sleeve 266 during vertic'alreciprocations thereof. Interposed between the disk 270 and the bevel gear 172 andsurrounding the shaft 260 is a spring 272 which tends constantly to move the disk 270 and sleeve 264 in an upward direction whereby-the bevel gear 256 may be caused to mesh with the pinion 254. In Fig. 12 of the drawings the stretching and tacking units 7 8 have all reached their positions of rest at the outer ends of their divergent paths and at thistime the shafts 96 are in inoperative position each with its pinioned end 170 raised above the large bevel gear 172. To start the machine in operation the operator depresses the handle 7 2 (Fig. 1) of the lever 68 which is connected by a link 274 with the outer end of a lever 276 pivoted on the frame of the machine at 27.8 and having a yoke portion 280 which embraces and is secured to a collar 282 freely rotatable in a groove formed in the attached hubs of the gear wheels 256,258. -Upon depressing the handle 72 the gears 256, 258 and the sleeve 266 are caused to move downwardl-y bringing the bevel gear 258 into mesh with the bevel pinion 254 and at the same time the disk 270 is caused to operate a plurality of bell-crank levers 290 each pivoted at 292 (Fig. 15) to a bracket 294 rigidly attached to.

the bracket or post 152. Each bell-crank lever 290 has an arm 296 which carries a roll 298 for engagement with the disk 270 and also another arm 300 adapted to engage with a pin 302 slidably supported in the carrier 166 by a spring 304. When the bell-crank lever 290 is rotated in a counter-clockwise direction by depression of the disk 270 from the position shown in Fig. 12 to that shown in Fig. 13, the arm 300 of the bell-crank is caused to press downwardly upon the pin 302 which through the spring 304 operates to depress the carrier 166 to such a point that the shoulder 162 on the carrier 166 is engaged by the latch 156 whereby the carrier is held in depressed position with the pinioned end 170 of each shaft 96 in meshing engagement with the large bevel gear 172 (Fig. 13). In this way all of the shafts 96 are rocked simultaneously into operative engagement with the bevel gear 1' 2 and are caused to rotate, thus moving all of the stretching and tacking units 78 simultaneously toward the center of the machine. gripper member 102 engages firmly with an edge portion of the piece of work, during movement of a unit 78 toward the center of the machine, the bar 144 is operated, as hereinbefore described, to cause movement of the As soon, however, as the to a stop with an edgeportion of the WOIk; engaged by the gripping means. As the carrier 166 rises the bell crank lever 290 is caused to move to the position shown in Fig. 15, that is, with the roll 298 pressing against a -vertical edge portion of the disk 270 instead of engaging with the upper surface of the mar ginal portion of the disk, as in Fig. 13, when the disk 270 was first depressed. In Fig. 14 the bell crank at the right of the figure has moved to the position'indicated in Fig. 15 while the other bell crank in Fig. 14 is still engaged with the top marginal surface of the disk 270. This means that the stretching and tacking unit corresponding to shaft 96 at the left in Fig. 14 is still moving toward the edge of the work or toward the center of the machine while that at the'right has ceased moving, having gripped an edge portion of i the work. In order to insure that the roll 298 on the arm 296 of the bell crank lever 290 will be moved away from the top marginal surface of the disk 270 upon the described upward movement of the carrier 166 there is provided on the carrier a slanting or cam surface 306 (Fig. 15) adapted to engage with a roller 308 supported by arm 310 of the bell crank lever 290 whereby the bell crank lever 290 is forced to the position shown in Fig. 15 depressing the pin 302 against the spring 304, the effect, however, not being sufficient to depress the carrier 166 far enough against the tension of the spring 168 to cause rcengagement of the latch 156. In other words. the carrier 166 is not depressed to its latched position where the shaft 96 will again become operative. The disk 270 remains de pressed in the position shown in Figs. 13-and 14 until the lastbell crank is released in the manner shown in Fig. 15. When the last bell crank 290 is released the disk.270 is at once moved upwardly by the spring 27 2 and in doing so it forces all of the bell cranks 290 to turn in a counter-clockwise direction, thereby depressing every one of the carriers 166, through pressure of the arm 300 of each bell crank upon the pin 302 in the carrier 166, to such an extent that eaclrlatch 156 again locks its associated carrier 166 in its depressed position whereupon all of the shafts 96 again become operative, as indicated in Fig. 16.-

with the bevel pinion 254and hence the direction of rotation of the vertical shaft 260 is changed. Hence, with the disk 270 in the position shown in Fig. 16, with the carriers 166 depressed, the shafts 96 are driving the stretching and tacking units-away from the center of the machine and, therefore, units are operating simultaneously to stretch all gripped portions of the piece of work and to tack them at various times as the tension in the stretched portion of the skin causes each gripping means in turn to letgo, with the resultthat a tack is driven to hold the stretched portion in stretched condition, it being understood that the tacking takes place while. the gripping means is releasing the edge of the gripped portion of the piece of work so that the tacking takes place before the work is actually released by the gripping means. As each stretching and tacking unit 5 78 arrives at the position shown at the left in Fig. 12 it moves the bar 144 to the left by engagement of the upright edge of the frame 90 with a stop block 320 (Fig. 1) at the outer end of the bar 144. As the bar 144 is thus dragged to the left in Figs. 1 and 12, .the latch 154 is dragged back from its position shown in Fig. 16 to the position shown in Fig. 12 and during this movement it causes disengagement of the latch member 156 from the carrier 166, thereby permitting the associated carriers 166 to rise whereby the shaft 96 is rendered inoperative through the raising of its pinioned end 170 away from the bevel gear 172. At the very end of the outward move.- inent of the units 78 the tack drivers are all reset in raised position through depression of the roller carrying end of each driver lever 113, as before described.

Just as each stretching and tacking linit 78 reaches its outermost position of rest, as described, or shortly thereafter, it receives a tack which is dropped into the tack pocket 222 by'means of an oscillatory chute section 330. The mechanism for delivering a tack from the magazine hopper 332 (Fig. 1) to the delivery chute section 330 will now be described. As shown, the hopper 332 has a hinged cover 334 which may be swung open to permit a quantity of tacks to be dumped into the hopper 332. In accordance with a well-known arrangement, the tacks slide in a mass from the hopper into a rotating magazine 336 which is constantly rotating, being driven by a a sprocket wheel (not shown) for the magazine 336 and also around a sprocket wheel at the right-hand end of a shaft 340 which carries at its left-hand end (Fig. 1) a second sprocket wheel adapted to be engaged by a chain 342 which also engageswith a sprocket (not shown) on the power shaft 250 of the machine. Hence, the magazine 336 is being constantly driven to feed tacks to a stationary raceway section 344. Since mechanism these in bearings provided by chain 338 which passes around for delivering tacks from a magazine to a raceway section is old and well known, as shown for instance in Patent No. 429,527, granted June 3', 1890, upon application of J. Hyslop, it is not shown nor described in detail. For receiving the tacks from the raceway section 344 there is provided a raceway section 346 mounted upon an arm 348 carried by a collar 350 fixedly secured to the upper end of a short, vertical shaft 352 which is mounted in a bearing 354 provided by bracket 356 carried by the frame of the machine. Below the bearing 354, the shaft 352 carries a bevel gear 358 (Fig. 6) which is constantly in mesh with a bevel pinion 360 carried loosely by a stub shaft 362 supported the bracket 356. At its other end the shaft 362 carries a bevel pinion 364 which is constantly in mesh with a bevel pinion 366 at the upper end of a vertical shaft 368 which carries at its lower end a bevel gear 370 in mesh with a bevel gear 372 secured to power shaft 250 which is consantly rotating as long as power is supplied to the machine through the pulley 352. As shown in Fig. 6 the shaft 362 is provided with a clutch member 374 which is rotatable with the shaft 362 and also slidable thereon into and out of engagement with a corresponding clutch member 376 which is securely attached to the bevel pinion 360. The arrangement is 1. To insure that this action takes place there is provided on the bevel gear 358 a roller stud 378 which engages with rounded end 380 of a clutch lever 382 to throw the'latter over to the left, as indicatedin Fig. 4, the movement of the lever being effected, in part, by the relatively light spring 384. In order to cause re-engagement of the clutch members 374, 376 there is provided an actuating means controlled by upward movement of the vertically movable beveled gears 256, 258. As will be clear from an inspection of Fig. 5, upward movement of the bevel gear 258 will cause upward movement of an operating block 390 which is mounted for vertical movement in a flange 392 projecting from the bracket 262 (Figs. 1 and 6). At its lower end the block 390 carries a roll 394 which rides on an annular projection 396 (Figs. 4 and 5) on the upper surface of the bevel gear 258. The block 390 also carries a pawl 398 pivoted thereto and operative to contact with a roll 400 at the lower end of the clutch lever 382 to cause movement of said clutch lever in a clockwise direction about its pivot point 402, thereby throwing in the clutch comprising members 374,376, the clutch remaining engaged because of the as this takes place the vertical shaft 352 is caused to rotate whereby the raceway section 346 is operated to swing its lower end in a circle past the upper ends of stationary chute sections 404 (Fig. 1). While the lower end of the raceway section 346 passes each chute section 404 it drops a tack therein, as will be hereinafter described. While the block 390 with its pawl 398 caused the throwing in of the clutch 374, 376 on upward movement of the block, downward movement of the block 390 will have no effect on the clutch member since the pawl 398 will swing idlyon its pivot during the downward movement of said block which takes place when the machine is started in operation by depression of the handle lever 68 (Fig. 1).

As before stated the lower end of the, raceway section 346 delivers a tack to the upper end of each chute section 404 in turn as it swings around a complete circle, separation of the tack from others at the lower end of the raceway and delivery to the chute section 404 being accomplished by means shown most clearly in Figs. 7, 8 and 9. From an inspection of these figures it will be observed that the raceway section .346 is provided at 'its lower end with a tack separator comprising a. slide 406 which carries at its upper end two picker plates 408, 410,spaced from each other in the direction of the length of the raceway section 346 and having their beveled ends spaced from each other sufficiently to permit the shank portion of a tack to pass between them upon movement of the two picker plates from the position shown in Fig. 9 to that shown. in Fig. 8. Upon reverse movement, the next tack slides down so that its shank portion is resting upon the beveled edge of the lower picker plate 410, as indi-.

cated in Fig. 9. For causing the described movements of the slide 406 and its attached picker plates 408, 410 there is provided a link lever 412 pivoted at 414 to the block 406, a spring 416 being provided for moving the lever 412 back to its normal position of rest after it has been moved through contact with one of the chute sections 404. For this purpose the spring 416 has one end attached to move the slide 406 and its picker plates.

408, 410 to the left, that is from the position shown in Fig. 9 to that shown in Fig. 8,

thereby causing the separation of a tack which is dropped into the open end of the chute-section 404 when the end of the raceway comes opposite a slot 422 in the side of the chute section 404. After the raceway has passed on dragging the yielding lever 412 by the chute section 404 the slide 406 is returned together with itspicker plates. 408, 410, to.

of the chute section 404, as shown in dotted lines in Fig. 10. The plate 430 is pivoted at 432 to a supporting bracket 434 supported by one of the arms or by one of the frame members 84, the plate 430 being held in its tack supporting position, with the tack chute 330 out of alinement with the chute section 404 as indicated-in dotted linepositions of the parts in Fig. 10, bymeans of a spring 438 secured at one'end to a pin 440 on the bracket 43,4 and at its other end to a pin 442 upon a link 444 pivoted at 446 to the/plate 430 and having at its other end a cross bar 448 having at one end a block 450 pivoted thereto at 452, the said'block being slidable in the guideway 454 while the other end of the cross bar 448 carries a roller 456 which is adapted to be engaged by a vertical edge portion of the frame of one of the stretc ing and tacking units 78. Just as the stretching and tacking unit 78 is reaching itsoutermost position of rest the frame 90 thereof contacts with the; 1

roll 456, as indicated in Fig. 7, and causes swinging of the plate 430 and with it the chute section 330 which is thus rotated through45 to bring its lower, ofi'set'end 458 directly over the tack pocket 222, and its open end in alignment with the chute section 404, whereupon the tack drops into the peak It will be clear that as soon as each stretching and tacking unit 78 starts on its journey toward the center of the machine the chute section 330 and its attached plate 430, will be rotated by spring 438 back to dotted line position (Fig. 10) in which the plate 430 serves as a tack support preventing escape of the tack from the upper stationary chute section 404 in which it is dropped from the raceway section 346 in the manner already described.

In the operation of the machine a piece of work, such as a skin, is placed upon a board 32 and the board and skin introduced into the machine by sliding the board over the table 30 while the latter is in depressed position, as indicated in Fig. 2, the operator takin care to position the board 32 with the skin thereon located with its central portion beneath the vertical shaft 260 at the center of the machine. The machine is then started in Operation by depressing'the starting lever 68 which, through the roll 80 operates the table lifting lever 46 to cause elevation of the table to work presenting position wherein it is locked by the latch 54 in the manner aldownwardly, and in doin so it operates simultaneously all of the be 1 crank levers 290 by which the carriers 166 are depressed to move the shafts 96 carried thereby into engagement with the large pinion gear 172,

thus starting the machine in operat1on,'since each shaft 96 causes movement of its associated stretchin and tacking unit 78 toward the center of t e machine, thus enabling the gripping means carried by each unit to engage the nearest edge portion of the work.

When a gripper member 102 engagesan edge portion of the work, it causes disconnection of the associated driving shaft 96 so that the each unit when it has engaged its portion of stretching and tacking unit comes to a stop,

the work. When the last unit has'come to rest the disk 270 is released from the bell crank levers 290 and in rising causes such a movement of the bell crank levers as to depress all of the carriers 166 to their lowermost latched positions wherein all of the shafts 96 are reconnected to the large bevel gear 172 which, at this time, is traveling in a reverse direction to that which it had at the starting of the machine. Hence, all of the stretching and tacking units 78 are caused to move simultaneously away from the center of the machine, thus placing the work under tension in all directions, stretching each portion according to the amount of natural stretch therein. Finally, when the tension on a given portion becomes greater than the tension of the spring 198 of the 'pping means the latter commences to lag hind its unit and this results in the driving of a tack which takes place before the work is actually released by the gripping means. Hence, all parts of the.

work are held either by the gripping means or by a tack until every part is tacked with the skin secured in stretched condition. Return of the stretching and tacking units 78 to their intital positions of rest results in disconnecting the shafts 96 from the driving gear 172 and-the parts are at rest with the table still locked in; raised position. The

operator may now step upon the tread portion 56 of the latch 54, thereby permitting the table to descend to a osition where the iece of work may be readi y removed and rep aced by another piece of work. r

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine for stretching hides, skins, leather and other similar ieces of work and securing them in stretche condition, a support havin a surface upon which a piece of work may e spread out, means com rising members movab e over the surface of t e support toward all sides of the piece of work on the support constructed and arranged to grip edge ortions of the piece of work, said members eing subsequently o rative for stretching the iece of work simu taneously in all directions rom a central portion thereof, and means for securing the piece of work along edge portions thereof while under ten- $1011.

2. In a machine for stretching hides, skins leather and other similar pieces of work and securing them in stretched condition, a support havin work may be spread out, means com rising members movable over the surface of t e support toward opposite sides of the piece of work on the support constructed and arranged to grip edge portions of a piece of work, said members being subsequently movable in reverse directions to efiect stretching of portions of the work away from each other upon opposite sides of a central portion there- 0 and means for. securing said edge portions while under tension.

3. In a machine for stretching hides, skins, leather and other similar pieces of work, a support having a surface upon which a piece of work may be spread out, and means comprising members movable over the work supporting surface of the support for engaging edge portions of a piece of work and for stretching the piece of work, said members being constructed and arranged to release a surface upon which a piece of each edge portion of the work when a predetermined tension is reached therein.

4. In a machine for stretching hides, skins,

leather and other similar pieces of work and securing them in stretched condition, a work support havin a surface upon which a piece of work ma e spread out, a plurality of devices mova le over the work supporting surface of the support to engage and grip edge portions of'a piece of work on the support, and means for causin the described movement of the devices an also movement of the devices in reverse directions so that the work may be stretched during movement of the devicesaway from each other, each device having means for securing in stretched condition 'a portion of the work engaged by the device. leather and other similar pieces of work, a

support having a surface upon which a piece In a machine for stretching hides, skins,

Ill'

6. In a machine for stretching hides, skins, leather and other similar pieces of work and securing them in stretched condition, a support for a piece of work, stretching means guided for movement to engage edge portions of a piece of work and for movement in a reverse direction to stretch the work, and securing means associated with the stretching means and arranged to be controlled by the tension developed in the portions of the work engaged by the stretching means, whereby successive portions of the work are secured in stretched condition as a predetermined tension is reached in each portion thereof.

7. In a machine for stretching hides, skins, leather and other similar pieces of work and securing them in stretched condition, a support having a surface upon which a piece of work may be spread out fiat, means having grippers movable over the work supporting surface for engaging and picking up edge portions of a piece of work on the support,

said grippers being movable in reverse directions for stretching the work, means associated with each gripper for securing the work in stretched condition, and-connections between each gripper and its associated securing means to determine the time of opera tion of the latter means.

8. In a machine for stretching hides, skins leatherand other similar pieces of work and securing them in stretchedcondition, a support for a piece of work, means having grippers for engaging edge portions of a piece of work on the support, means to move the grippers to effect a stretching of the piece of work, a securing means associated with each gripper to cited securing of the work when a predetermined tension has been established between the gripper and the gripped portion of the work, and means operated by the securing means to cause its associated gripper to release the work following the securing operation on the gripped edge of the work.

9. In a machine for stretching hides, skins,

leather and other. similar pieces of work and securing them in stretched condition, a support for a piece of work, means comprising grippers for engaging edge portions of a piece of work, means to move the grippers to effect a. stretching operation on the work, securing means associated with each gripper and arranged to be controlled by the gripper to effect securing of the portion of work held by the gripper when a predetermined tension of the work has been reached, and connections between the securing means'and its associated gripper to effect release of the work from the gripper immediately after the operation of the securing means.

10. In a machine for stretching hides, skins, leather and other similar pieces of work, a support for a piece of work, a plurality of devices each having a gripper for engaging an edge portion of a piece of work,-

means individual to'each device for effecting movement thereof'in a direction toward the work and controlled by the gripper to terminate the movement of the device when the work has been securely gripped, and means for simultanenously reversing the movement of all of thefdevices to effect a stretching operation on the piece of work.

11. In a machine for stretching hides, skins, leather and other similar pieces of work, a support for a piece of work, a plu rality of devices each comprising means for engaging an edge portion of a piece of work, means for eflecting movement of said devices toward the work and causing said devices to pick up and engage the work, and means automatically operative for reversing the movement of the'devices to effect a stretching operation on the piece of work.

12. In a machine for stretching hides, skins, leather, and other similar pieces of work, a support for a piece of work, a plurality of stretching devices movable for engaging edge portions of a piece of work on the support, means for moving the devices toward the work, a feeler mechanism associated with each device for engaging the work and operative to control the moving means for the devices so as to terminate the movement of each device after the latter has engaged with an edge portion of the work, and means -for causing simultaneous movement of the devices away from each other on opposite sides ofthe work to effect stretching of the piece of work.

13. In a machine for stretching hides, skins, leather and other similar pieces of work and securing them in stretched condition, a work support, and a plurality of devices movable to engage a piece of work, each device having a gripper for picking up and gripping an edge portion of the piece of work so that the work may be stretched during movement of the devices away from each other, each device also having means controlled by its associated gripper for securing. in stretched condition a portion of the work operated upon by the associated gripper.

14. In a machine. for stretching hides, skins, leather and other similar pieces of, work, a support for a piece of work, a plurality of devices having each a gripper for engaging edge portions of a piece of work on the support, means for moving the devices toward the work, each gripper having a feeler associated therewith for engaging with the work and operative to control the moving means for the devices so as to terminate the movement of each device after the gripper has gripped an edge portion of the work, and means for causing simultaneous movement of the devices away from each other on opposite sides of the work to effect stretching of the piece of work.

15. In a machine for stretching hides,

- portion of the work, and

' posite directions from a central portion.

- skins,

skins, leather and other similar pieces of work and securing them in stretched condition, a support for a piece of work, a plurality of stretching and tackin units movable toward edge portions of a P1002 of work on the support to engage said edge portions and subsequently movable away from each other upon opposite sides of a iece of work to stretch the work in many 'rections from a central portion thereof, means for causing the described movements of the stretching and tacking units, and means controlled by the work for determining the extent of movement of each unit when moving to engage the work.

- 16. In a machine for stretching hides, skins, leather and other similar pieces of work and securing them in stretched condition, a support for a piece of work, a plurality of stretching and tacking units movable toward edge portions of a piece of work on the support to engage said edge portions and subsequently movable away from each other upon opposite sides of the piece of work to stretch the piece of work away from a central portion thereof, means for moving the units to cause them to engage edge portions of the work controlled by the work so that each unit stops when an edge portion has been seized by the unit, and means for automati-.

cally moving the units away from each other upon opposite sides of the piece of work to effect stretching thereof.

17. In a machine for .stretching hides, skins, leather and other similar pieces of work and securing them in stretched condition, a support for a piece of work, a plu rality of stretching and tacking units movable to engage edge portions of a piece of work on the support and subsequently movable awa from each other upon opposite sides of t e piece of work to eifect stretching thereof, means individual to each unit for moving it in the direction described,means controlled by the work for rendering the moving means of each unit inoperative when its associated unit has engaged with an edge means for again rendering all of the movin means for all of theunits operative where y the units are caused to stretch portions of the work in obthereof.

18. In a machine for stretching hides, leather and other similar pieces of work and securing them in stretched condition, a support for a piece of work, a plurality of stretching and tacking umts movable to engage edge portions of-a iece of work on the support and subsequent y movable away from each other upon opposite sides of the piece of work to effect stretching thereof, a shaft individual to each stretching and tacking unit movements thereof, means for driving all of for causing the described the shafts,,means controlled by the work for causing disconnection of each shaft from the driving means when its associated unit has engaged with the work, and means for causing re-engagement of all of the shafts with the driving means to effect movement of the supportfor a piece of work, a plurality of stretching and tacking units movable to engage edge portions of a piece of work on the support and subsequently movable away from each other upon opposite sides of the piece .of work to effect stretching thereof, means individual to each unit for moving it in the directions described, means controlled by the work for rendering the moving means of each unit inoperative when its associated unit has engaged with an edge portion of the work, and means for rendering all of the moving means for all the units simultaneously operated whereby the units are caused to stretch portions of the work simultaneously in opposite directions from a central portion thereof.

20. In a machine for stretching hides, skins, leather and other similar pieces of work and securing them in stretched condition, a support for a piece of work, a plurality of stretching and tacking units movable to engage edge portions of a piece of work on the support and subsequently movable'away from each other upon opposite sides of the piece of work to effect stretching thereof, a shaft individual to each stretching and tacking unit for causing the described movements thereof, a gear for driving all of the shafts, means controlled by the work for causing disconnection of each shaft from the driving gear when its associated unit has engaged with the work, and means for causing re-engagement of all of the shafts with the gear wheel to effect simultaneous movement of the units in directions to stretch thework.

21. In a machine for stretching hides, skins, leather and other similar pieces 'of work, a support for a pieceof work, a plurality of stretching devices movable for engaging edge portions of a piece of work on the support and subsequently movable away from each other on opposite sides of the work to effect a stretching of the piece of work, individual means for causing the described movements of eaeh'device, feeler mechanism associated with each device for engaging with the piece of work to control the extent of movement of each device, and means automatically operative for controlling the moving means for the devices for causing movement of the devices simultaneously to effect a stretching of the piece of work.

22. In a machine for stretching hides, skins, leather and other similar piecfs of work, a support for a piece of work, a p urality of de- Ill vices each comprising a gripper and movable in converging directions to engage edge portions of a piece of work on the support and also in diverging directions to stretch the piece of work, and individual means for causing the described movements of each device,

said gripper having connections for controlling the moving means of its associated device, whereby the converging movement of each devlce is terminated when an edge portion of the work has'been gripped.

'23. In a machine for stretching hides,

skins, leather and other similar pieces of work; and securing them in stretched conditions, a support for a piece of work, a plurality of stretching devices for engaging edge nor-- tions of a piece of work subsequently operative for'eflfiecting a stretching operation upon the work, and a securing means associated with each devlce and arranged to become operative when the tension on the edge portion reaches a predetermined maximum.

24. In a machine for stretching hides,

skins, leather and other similar pieces of work I and securing them in stretched condition, a work support having a surface upon Wl'llCll' a piece of work may be spread out, and a plusecuring in stretched condition a portion ofthe work operated upon by the associated s pr 25.- In a machine for stretchmg hldes, skins, leather and other similar pieces of work" and securing them in stretched condition, a

table for supporting aboard and a piece of work spreadout thereon, a plurality of devices movable overthe board for plcking up and gripping edge portions of a piece of work and stretching it and each having-means for securing a portion of the workto the board in stretched condition, and means for moving the devices away from each other on opposite sides of the work to stretch the piece of work and to effect operation of the securing means.

26. In a machine for stretching hides,

skins, leather and other similar pieces of work and securing them in stretched cond1tion,-a

supportfor'a piece of work, a plurality of:

devices for engaging and stretching a piece of work simultaneouslyinall directions from a :centralportion thereof, and a work securing means associated with each device and-ar'- ranged to be controlled thereby for securing the work in stretched condition when .a predetermined tension on the work is reached.

27. In a machine for stretching hides,

skins, leather and other similar pieces of work and securing them in stretched condition, a support for a piece of work, a plurality of stretching devices each guided for movement to engage an edge portion of a piece of work and for movement in a reverse direction to stretch the work, means for moving the devices. in the directions stated, and securing means associated with each device and arranged to be controlled by the tension on the work, whereby the work is secured in stretched condition 'when a predetermined tension is reached between each individual device and the portionof work gripped thereby.

28. In a machine for stretching hides, skins, leather and other similar pieces of work and securing them in'stretched condi-- tion, a support for a piece of work, a plurality of devices each having gripper means for engaging edge, portions of the piece of work on the support, means, individual to each device for movlng the same in a direction to engage the work andalso in areverse direction to stretch the work, said gri per means serving as a feeler mechanism or engaging the work to controlthe movingmeans to termimeans to determine the time of operation of the'l'atter means.

29. In a machine for stretching hides, skins, leather and other similar pieces of work and securing them in stretched condition, a

support for a piece of'work, a plurality of devices each havinga gripper for engaging an edge portion of a piece of work .on the sup-- port, means for moving the devices to cause the grippers to engage the work and for moving them subsequently in'reverse directions to effect a stretching of the piece of work, and a securing, means associated with each device to efl'ect securing of the work when a predetermined tension has beeir established between the gripper and the gripped portion of the work, said securing means being operativeto cause its associated gripper to release the work following the securing operation on the gri ped edge of the work.

" 30. 1 h a machine for stretching hides,

skins, leather and other similar pieces of.

work and securing them-in stretched condition, a support for a piece of work, a lurality of devices having each a gripper or engaging an'edge portion of a piece of work during movement of the devices toward edge portionsfof the work, means for moving the devices simultaneously away from eachother .:on opposite sides of the work to effect a "stretching operation on the work, securing means associated with each device and arranged to be contrclled by the grip or to effect securing of the portion of wor held by the gripper when a predetermined tension thereof has been reached, and connections between the securing means and its associated gripper to efiect release of the work from the gripper immediately after the operation of the securing means.

31. In a machine for stretching hides, skins, leather and other similar ieces of work and securing them in stretched condition, a support for a piece of work, a plurality of devices for engaging and stretching a piece of work on the support, a securing means associated with each stretching device, means controlled by the stretching device for causing operation of the securing means on the work when a predetermined tension of the work has been reached, and connections between the securin means and its associated stretching device or causin the latter to release the work immediately a er the operation of the securing means.

32. In a machine for stretchin hides, skins, leather and other similar pieces of work and securing them in stretched condition, a support for a board and a piece of work spread out thereon, a plurality of devices movable over the board and each having a gripper for engaging an edge portion of a piece of work said devices being movable away from eac other on opposite sides of a piece of work to efiect stretching operations thereon, a tacker mechanism associated with each device for securing a stretched portion of the work to the board, and connections between the gripper and the tacker mechanism for controlling the latter to set a tack before the work is released by the gripper.

33. In a machine for stretching hides,

-. skin's, leather and other similar pieces of work and tacking them in stretched condition, a work support, and a plurality of devices moV able toward and away from a common center, each device having a gripper for seizing an edge portion of the piece of work during movement of the device toward the center so that the work may be stretched during movement of the devices away from the said center, each device also having means for driving a tack during movement of the device away from said center.

34. In a machine for stretching hides, skins, leather and other similar ieces of work and tacking them in stretche condition, a table for supporting a board and a piece of work spread out thereon, a plurality of devices movable over the board-for gri ing and for stretching a piece of work an avother on op osite sides of the work to stretch the piece 0 work and to effect operation of the tacking means.

35. In a machine for stretching hides, skins, leather and other similar pieces of work and tacking them in stretched condition, a

support for a piece of work, and a plurality of devices for engaging and stretching a iece of work simultaneously in all directions rom a central portion thereof, and a tacking means associated with each device and arranged to be controlled thereby for inserting a tack when a predetermined tension on the work is reached.-

36. In a -ma'chine for stretching hides, skins,- leather and other similar pieces of work, a support for a piece of work, a pluraL ity of devices movable toward each other upon opposite sides of a piece of work in order to engage edge portions of the piece of work-on the support, individual means for causing the described movement of each device, a gripper associated with each device 'for engaging an edge portion of the piece of work, said gripper having connections for controlling the moving means of its associated device, and 'meam for reversing the direction of movement of the devices to put the piece of work under tension.

37. In a machine for stretching hides, skins, leather and other similar pieces of work, a support for a piece of work, a plurality of devices each having gripper means -for en-- gaging edge portions of the piece of work on the support, means individual to each device for moving the same in a direction to engage the work, said gripper means serving as a feeler mechanism for engaging the work and for controlling the moving -means to terminate the movement of the device after the gripper has seized the work, and means for reversing the direction of movement of the devices and causing simultaneous movement of the devices to put the piece of work under tension.

38. In a machine for stretching hides, skins, leather and other similar pieces of work, a support fora piece of'work, a plurality of devices for enga ing edge portions of the piece of work on t e support, means for moving the devices simultaneously toward the work, a feeler mechanism assothe movement of the device after the'latter has engaged with an edge portion of the work, and means for reversing the moving means to cause simultaneous movement of the devices along diverging paths to efiect stretching of'the piece of work. v

39. a machine for stretching hides, skins, leather and other similar ieces of work, a support for a piece of wor a plurality of devices movable along converging paths for engaging edge portions of the piece of work on the support and subsequently movable along divergin paths to effect a stretching of the piece 0 work, individual means for; causing the described movements of each device, andcfeeler mechanism associated with each device for engaging with the nearest portion of the piece of work and operative to control the extent of converging movement of each device, and m ans automatically operative for controlling the moving means for the devices for causing movement of the devices simultaneously along diverging. paths to efiect a stretching of the piece of worln Y 40. In a machine for stretching, hides, skins, leather and other similar pieces of work and tacking them in stretched condition, a support for a piece of work, a plurality of devices for engaging edge portions of a piece ofwork subsequently operative for efi'ecti'ng a stretching operation upon the work, and a tacking means associated with each device and arranged to be controlled thereby to become operative when the tension on the edge portion reaches a predetermined maximum.

41. In a machine for stretching hides,-

skins, leather and other similar pieces of work and tacking them in stretched condition, a support for a piece of work, a plurality of devices arranged to engage edge portions of a piece of work, means for moving the devices for efiecting a stretching operation on the piece of work, and tacking means associated with each device and arranged to be controlled by the tension on the work, whereby a tack is driven into the work when 'a predetermined tension is reached between each individual device a nd the. portion of work gripped thereby;

42. In a -machine for stretching hides,

skins, leather and other similar pieces of.

work and tacking them in stretched condition, a support for a piece of work,=a plu rality of devices arranged in a circle about a given center and guided for movement in converging paths to engage edge portions of" a piece of work, means formoving the devices in diverging directions for effecting a stretching operation on the piece of work, and tacking means associated with each device and arranged to be controlled by the tension on the work, whereby a tack is driven into the work when a predetermined tension is reached between each individual device and the portion of work gripped thereby.

43. In a machine for stretching hides, skins, leather and other similar pieces of work, a support for a piece of work, a plurality of devices movable along converging paths, each device having a gripper for engaging an edge portion of the piece of the work, means individual to each device tor effecting movement thereof in a direction toward the work controlled by the gripper to terminate the movement 0 the device when the work has been securely gripped, and means for simultaneously moving all of the devices along divergent paths to eflect a stretching operation of the piece of work.

- port, means for moving the devices to engage the work and subsequently to eitect a stretching of the piece of work,a tacker mechanism associated with each device having a tack driver and a locking means for holding the tack driver in raised position, and connections to the gripper for tripping the locking means when a predetermined tension has been established between the gripper and the gripped portion of the work to cause the driving of a tack.

45. In a machine for stretching hides, skins, leather and other similar pieces of work and tacking them in stretched condition, a support for a piece of work, a plurality of devices havmg each a gripper for engaging an edge portion of the work during movement of the devices toward edge portions of the work, means for moving the devices simultaneously along divergent paths to efi'ect a stretching operation on the work, tacker mechanism associated with each deviceand arranged to be controlled by the gripper to effect a tacking of the work when a predetermined tension thereof has been reached, and means for automatically resetting each tacker mechanism to site t a driving of a tack in the next cycle of "tensionof the work has been reached, and

connections between the tacker and the .gripper for causing the latter to release the work at the instant that a tack is driven into the c stretched portion of work.

' 47. In a machine for stretching hides, skins, leather and other similar pieces of work and tacking them in stretched condition, a support for a piece of work, a plurality of devices each having a gripper for engaging anledge portion of the piece of work, means for moving said devices to effect stretching of the piece of work, a tacker mechanism associated w th each device, and connections between the gripper and its associated tacker mechauisnifor controlling the latter to'cause the drlvmg of a tack in the stretched portion of the work and to cause the gripper to release the work at the instant of driving the tack into the work.

48. In a machine for stretching hides ,skins, leather and other similar pieces of work and

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