US2891264A

US2891264A - Machines for forming shoe covers

Info

Publication number: US2891264A
Application number: US648541A
Authority: US
Inventors: Hans C Paulsen
Original assignee: BB Chemical Co
Current assignee: BB Chemical Co
Priority date: 1957-03-26
Filing date: 1957-03-26
Publication date: 1959-06-23
Anticipated expiration: 1976-06-23

Description

June 23, 1959 H. c. PAULSEN 2,89 ,26

MACHINES FOR FORMING SHOE COVERS, Fild March 26, 1957 8 Sheets-Sheet 1 Inventor Hans CPau/sen By his Attorney J 23,1959 H. c. PAULSEN MACHINES FOR FORMING SHOE COVERS 8 Sheets-Sheet 2 7 Filed March L26. 1957 mam nwm Em uJ p m 0h tu n mI 0 6 mm HUM June 23, 1959 H. c. PAULSEN 2,891,264

MACHINES FOR FORMING SHOE COVERS Filed March 26, 1957 8 Sheets-Sheet 4 [n uenion Hans-C/Qmlsen By his Attorney June 23, 1959 H. c. PAULSEN 2,391,264

MACHINES FOR FORMING SHOE COVERS Filed March 2 1957 a Sheets-Sheet 5 [nven 0P Hans C. Paulsen By his Attorney June 23, 1959 H. c. PAULSEN MACHINES FOR FORMING SHOE COVERS 8 Sheets-Sheet 6 Filed March 26, 1957 fnuenfaw Hans C Pau/sen By has Attorney June 23, 1959 H. c. PAULSEN MACHINES FOR FORMING SHOE COVERS 8 Sheets-Sheet 7 Filed March 26, 1957 lhverzfow Hans C(Fiz'ulsen By his Attorney June 23, 1959 H. c. PAULSEN 2,891,264

MACHINES FOR FORMING SHOE COVERS Filed March 26. 1957- 8 Sheets-Sheet B 28 /nvehfor 22 Hqms af ulsen Y By his Attorney United States Patent 2,891,264 Patented June 23, 1959 Fice =MACHINES FOR FORMING SHOE COVERS Hans C. Paulsen, Lexington, Mass, assignor to BB.

Chemical Co., Boston, Mass., a corporation of Massachusetts Application March 26, 1957, Serial No. 648,541

1'2 Claims. (Cl. 1'2-1) This invention relates to machines for forming from flat blanks protective covers to be applied to the uppers of shoes during the manufacture of the shoes. Such covers are employed to prevent soiling or staining of the shoe uppers in the course of the manufacture of the shoes.

One form of cover produced by the machine of the present invention, and a machine for applying the cover to a shoe, are illustrated in Letters Patent of the United States No. 2,712,659, granted July 12, 1955, on an application filed in my name.

An object of the present invention is to provide an improved machine for forming protective covers for shoes from fiat blanks of thin plastic material. To this end and in accordance with a feature of the invention, the machine includes means for turning the side portions of the blanks into generally parallel relation and means for turning the heel portions of the sides of the blanks inwardly into overlapping relation and bonding together the overlapped portions.

After the blanks have been formed into covers the covers are moved out of the forming station and are stacked in nested relation. In accordance with another feature of the invention the stacking station receives the formed covers in inverted positions and includes means for holding the upper margins of the covers in outwardly turned positions in the stacking station and means operative during the feeding of a blank into the stacking station for retracting the holding means and spreading the margins of the cover outwardly into contact with the cover in which it is nested.

The cover blanks include tab portions projecting from a margin thereof to facilitate separation of the nested cover blanks when they are to be used. Further to facilitate this separation and in accordance with another feature of the invention the forming station of the machine includes means for doubling the tab portions to form two-ply portions having twice the thickness of the covers and sealing the plies of the tab portions together.

The above and other features of the invention including various details of construction and novel combinations of parts will now be described by reference to the drawings and pointed out in the claims.

In the drawings,

Fig. 1 is a right side elevation of one form of machine in which the invention is embodied;

Fig. 2 is a plan view, partly in section, of the formin station of the machine;

Fig. 3 is a right side elevation, partly in section, of the forming station;

Fig. 4 is a section on the line IV-IV of Fig. 3;

Fig. 5 is a rear elevation, partly in section, of the forming station;

Fig. 6 is a rear elevation, partly in section, of a portion of the forming station;

Fig. 7 is a view of some of the parts of Fig. 6 with the parts in different positions;

Fig. 8 is a plan view of the back seam closing members,

showing their relative positions prior to closing of the back seam;

Fig. 9 is a plan view of the stacking station of the machine;

Fig. 10 is a section on the line XX of Fig. 9;

Fig. 11 is a detail plan view of the inner form or transfer device illustrating the means for separating the sides of the shoe cover therefrom;

Fig. 12 is a side elevation of the mechanism shown in Fig. 11, and

Fig. 13 is a rear elevation of a portion of the mechanism shown in Figs. 11 and 12.

The illustrative machine comprises a forming station 10 (Fig. 1) and a stacking station 12 having Work supporting tables 14 and 16 respectively carried by upstanding legs 18 of a supporting frame. The Work supporting table 14 is generally horizontally disposed and the table 16 is inclined downwardly and rearwardly therefrom, this latter table being adjustably secured to one of the legs 13 by a screw and slot connection 20.

A forming block 22, see for example Fig. 12, is arranged for movement from a position above the table 14 of the forming station where it cooperates with mechanism to be described for turning up the sides of the shoe cover and for closing the back seam, to a position above the table 16 whereby it carries the formed shoe cover from the forming station to the stacking station. The forming block 22 has secured to its top face by screws 24 a pair of spaced plates 25 one of which carries an upstanding bracket 26. The plates 25 form between them a T-shaped guideway 23 (Fig. 5) for a slide 30, the purpose of which will appear hereinafter.

The upper end of the bracket 26 is pinned to a shaft 31 which is in turn journaled in a sleeve 32 extending transversely of the machine. The sleeve 32 is carried at the upper end of a swinging arm 34 the lower end of which is pivoted at 36 (Fig. 1) to one of the frame members. Pivoted to the swinging arm 34 near its upper end is a forwardly extending arm 38 provided with a handle 40 at the front of the machine with the parts in the positions illustrated in Fig. 1 so that upon rearward movement of the handle 40 and the arm 38 the swinging arm 34 moves clockwise about the pivot 36 to carry the forming block 22 rearwardly from the forming station to the stacking station.

Provision is made for imparting a swinging movement to the forming block about the axis of the shaft 31 (Fig. 5) as it is moved from the forming station into the stacking station so that the completed covers will be delivered at the proper angle into the stacking station. For controlling the swinging movements of the forming block an arm 42 (Fig. 5) is secured to the outer end of the shaft 31 and carries a cam roll 44 arranged for engagement with a cam track 46 (Figs. 1 and 9) secured to a bracket 48 on the table 16 of the stacking station. As the swinging arm 34 moves clockwise about its pivot 36 (Fig. 1) the cam roll 44 engages the upper surface of the cam track 46 thus moving the arm 42 upward and swinging the forming block relatively to the arm 34 in accordance with the curvature of the cam track, against the action of a spring 50 acting between. an arm 52 depending from the cam roll supporting arm 42 and connected between screws in the arm 52 and the swinging arm 34. With the forming block at the forming station, its position relatively to the work table 14 is determined by an adjustable stop screw 54- (Fig. 1) carried by the arm 52 and engaging a boss on the swinging arm 34. The arm 34- extends below the pivot 36 and is connected by a forwardly extending link 56 to a lever 58 pivoted at 60 to the frame of the machine and extending upwardly to a position alongside the forward edge of the work table 14. For holding the block 221 in its forwardmost position in the forming station during the forming operation, the upper end of the lever 53 is releasably held in the position of Fig. '1 by a suitable latch 62, thus maintaining the link 56, the lever 34 and the arm 38 in the positions shown 'in Fig. 1 until a rearward force of sufficient magnitude is exerted onthe handle to overcome the holding effect of the latch.

The shoe'cover-blanlcs are presented to themachine in flattened condition beneath the forming block 22 and the sides .are then moved upwardly against opposite side faces of the forming blockafter which the back seam is closed and heat is applied thereto to effect a permanent closure thereof. For thus turning the sides of the cover against the side faces of the forming block a pair of forming

plates

64, 65 are hinged to the work table at .66 (Figs. 2, 5 and 6) and provide the surface :WlliCll receives a .shoe cover blank B as shown in'Fig. 2. The forward end of the forming .block22 is in the form of a forwardly extending tongue 67 (Fig. 12) the lower surface of which is slightly above ,thelowersurface of the forming block proper, thus providinga spacebetween the tongue and the forming plates .to receive the toeportion of the shoe cover blank. The rearward ends of the forming

plates

64, 65 are curved as clearly shown in Fig. 2 to correspond to the vertical curvature .of the heel portion .of a shoe, and the block 22 (Fig. 12) 'is correspondingly curved.

Pivoted to the forming

plates

64, 65 at68 (Fig. 8) are arms 71 72 which carry at their outer ends means for folding the heel end portions of the shoe cover blank in overlapping relation to form a back seam. Secured to the forming

plates

64, 65 are rods 74 (Fig. 5) which pass through openings in the arms '70, 72 and carry collars 76 near their outer ends. Tension springs '78 are connected between the collars 76 and the arms 70, '72 to maintain the outer ends of the arms in spaced relation to the forming

plates

64, 65 as shown in Fig. 8. Collars 80 carried by the rods 74 (Fig. 5) limit the outward movement of the arms Ti 72 with respect to the forming plates.

For moving the forming

plates

64, 65 about their pivots 66 to turn the sides of the cover blank into engagement with the sides of the forming block 22, mechanism shown in Fig. 5 is provided. This mechanism comprises levers 82 pivoted on a shaft '84 and having se- .cured to their outer ends arms 86 carrying rolls 68 en- .gageable with the lower surfaces of the

arms

70, 72 with the parts in the positions shown in Fig. 5. Upon upward movement of the levers 32 about the shaft 84 the forming

plates

64, 65 are moved upwardly, the force be ing exerted through the

arms

70, 72 and the tension springs 73. Pivoted to the levers 62 are downwardly extending

arms

96, 92 carrying cam rollers 94-, 96, the arms having slots 98 through which'passes a cam shaft liltl. Cams 102, 164 are carried by the cam shaft 1% and rotate in a counterclockwise direction, as viewed in Fig. 5, during the operation of formingthe blank into the shoe cover. Upon rotation of the cams 102, from the positions illustrated in Fig. 5, the arms $2 move upwardly first to move the forming plates into substantially vertical positions alongside the forming block following which the arm 70 is moved against the action of the tension spring 78 into engagement with its associated forming plate. Following this the arm 72, associated with the other forming plate moves into engagement with it following which the first arm 70 moves away'from its forming plate.

.The arm '70 carries at its outer end a slotted plate 106 (Figs. 6 7 and 8) provided with slots 108 which are located to receive fingers 110 secured to the arm 72 when the two plates are closed against the associated forming'plates. The plate 106 will first move from the position shown in Fig. 8 to the right to turn over the heel portion of the cover blank against the rearward face .ing plates upwardly as aforedescribed. .of course that the shaft 122 may, if desired, be powerof the forming block 22 following which the fingers carried by the arm '72 move to the left as viewed in Fig. 8 to turn in the other heel portion of the blank against the outer face of the plate 106 and hold the portions in overlapping relation. Following this the plate 106 moves with its arm 70 back to the position shown in Fig. 8 so that the overlapped heel portions are in engagement and are exposed except for the portions underlying the fingers 110 for theapplication of heat whereby they are sealed to complete the formation of the heel portion of the cover.

The cam shaft 3,100 carries at its forward end a'bevel gear 112 (Fig. 2) which meshes with a bevel gear' 114 carried by a transversely extending shaft .116 having a sprocket 118 connected by a sprocket chain 120 (Fig. l) with a sprocket .on a 'drive shaft 122. This drive shaft has secured to it a handle 124 whereby the shaft may be turned and the

cams

102, 104 operated to move the form- It will be obvious operated.

Carried by the shaft116 is a cam 126 arranged, after the heel portions have been folded and are clamped by the fingers 11 with .the plate 1456 in retracted position, .toclosea microswitch 128 carried bya frame member of at 138 .(Fig. 3) to an arm 140 secured to apinion 142 carried by a-shaft 144. The pinion 142 meshes with a .pinion 146 .secured to a shaft 148 carrying .arms 156 (Fig. .6) the outer ends of which carry ,a pin1-52 on-which is supported a heating block 154 .havin-ga cunved face, as shown .in Fig. 1,-complemental .to the rearward face of the forming block 22 so that when the heating block is moved downwardly from the position shown in :Fig. 1 into the .position shown in Fig. 3, heatis applied to the overlapped heel end portions of the .cover to seal them together. When the solenoid 130 is energized-the pinion 142 is turned in a counterclockwise direction imparting clockwise movement to the pinion 146 which acts through the arms 150 to carry the heating block into operative position. Heat is supplied to the heating block 154 by a cartridge-type heating element 156. A torsion spring 158 (Fig. 6) has one end connected to a collar 160 on the shaft 148, the collar being held in any one of a.plurality of positions by a screw 162 threaded through a bracket 164 and having a reduced end arranged to be received .byone of several holes .166 in the collar. The spring 153 acts to move the .pinion 146 in a counterclockwise .direction, as viewed in Fig. 3 when the solenoid is deenergizedand the effectiveness of this spring is readily varied by adjusting the position of the collar 160.

To facilitate separation of the formed blanks after they are nested together in the stacking station the blanks are provided with tabs T illustrated in Fig. .2. Inthe formation of the covers these tabs are folded .over to provide portions of double thickness to increase their effectiveness. As shown in Fig. 2 the forming plate 64 at the right side of the machine does ,notextend as far forwardly as does the forming plate 65 at the other side of the machine. Underlying the forward portion of the fiat blank when the blank is presented to the machine is a plate 168 pivoted at 170 in alinement with the pivot 66 of the adjacent forming plate 64. The outer corner of the plate 168 adjacent the forming plate 64 is cut away and a ,pair of stiff Wires 172 carried by the plate .168 extend into the recess formed by the cut away portion. The tab T overlies these wires with the plate v168 in horizontal position, there being a supporting .block 174 for the wires 172. An arm 176 secured to the forming plate 64 underlies the plate 163 so that when the forming plate 64 is moved upwardly the plate 168 will move assneeait s) therewith. However, the forming plate may move downwardly without causing similar movement of the plate 168.

Upon upward movement of the plate 168, as illustrated in Fig. 4, the outer portion of the tab T is turned back upon the tab by engagment of the tab with a pressing block 178. With the forming plates in vertical positions that portion of the tab T adjacent to the body of the blank is held by the wires 172 in engagement with a heating block 180 carried by and depending from an insulating block 182 carried by an overhead arm 183 (Fig. 3) which extends lengthwise of the forming station. A heating element 184 (Fig. 1) is secured to the forward face of the heating block 189. The face of the heating block against which the tab is moved by the plate 168 is provided with recesses 186 to receive the wires 172.

The pressing block 178 is pivoted to an arm of a bell crank lever 188 the other arm of which is pivoted to the heating block. The intermediate portion of the bell crank lever has pivoted to it a vertically extending rod 190 which carries a pair of spaced collars 192 (Fig. 3) the opposed faces of which are curved to receive between them one arm of a bell crank lever 194. This lever is pivoted at 196 to an upwardly extending portion 198 of the insulating block 182. A depending arm of the bell crank lever 194 has near its lowest end an aperture through which passes a rod 200, the forward end of which is threaded to receive nuts 202 which abut one end of a spring 204 surrounding the rod, the spring also engaging the forward face of the depending arm of the bell crank lever. The rearward end of the rod 206 is pivotally connected at 206 to one of the arms 150 carrying the heating block 154, the pivot 206 being so related to the pivot 148 for the arms 150 that when the heating block 154 is moved into operative relation to the shoe cover the. rod 200 moves rearwardly and through the spring 204 causes downward movement of the vertically extend ing rod 190 thus moving the bell crank lever 188 (Fig. 4) in a counterclockwise direction causing the pressing block 178 to press the overturned portion of the tab T back upon the tab whereby it is sealed by the heat of the heating block 180. The pressing block 178 has recesses 208 in its pressing face which cooperate with the recesses 186 in the heating block 180 to receive the wires 172 and prevent the application of pressure to the tab in the vicinity of the wires.

At the end of the forming operation after the back seam and the tab have been subjected to the application of heat for a short period of time, sutiicient to seal the layers of material together, the shaft 122 is turned to return the heating block 154 and the pressing block 178 to their original positions out of engagement with the blank and the forming plates are returned to their orig inal positions. However, the plate 168 by which the tab T was folded remains in its upstanding position because the wires 172 are located between the two plies of the tab. Since the plies of the tab are not heat-sealed in the location of the wires 172, the tab is readily removed therefrom upon rearward movement of the now completely formed cover when the forming block is movedrearwardly. As previously explained this rearward movement is eifected by moving the handle 40 (Fig. 1) rearwardly and shortly after this movement has started the plate 168 is returned to its horizontal position. For this purpose a vertically-extending rod 214B moves upwardly through the work support to engage an arm 211 (Figs. 2 and 3) extending inwardly from the pivot of the plate 163 to initiate return of the plate when the arm is moved upwardly after which the plate falls by gravity into its horizontal position. The rod 210 is slidable in a fixed guide 212 and secured to the rod by a collar 214 is an arm 216 having a forwardly extending portion carrying on its undersurface a cam 218. The shaft carrying the lever 58 has secured to it an upstanding arm 220 which, upon rearward movement of the forming block, moves clockwise engaging the cam 6 218 and causing momentary upward movement of the rod 210 thereby to cause return of the plate 168 by which the tab is folded and formed.

The stacking station 12 (Fig. 10) comprises the table 16 having fixed thereon a wedge-shaped member 222 for supporting the heel end portions of the formed covers which are moved into position by rearward movement of the forming block 22. The covers are moved rearwardly by the forming block until the heel end portions are located by an abutment 224 adjustably carried by a holder 226 secured to an upstanding arm 228 of a plate 230. A guide screw 232 passes through a slot in the plate 230 and a second screw 234 passing through the plate and threaded into an extension of the table 16 has confined between its head and the plate 230 a spring 236 arranged frictionally to hold the plate 230 in position on the table. At the beginning of the operation of the machine the plate 230 is located in. its forward position so that the first cover blank formed and delivered to the stacking station will engage the abutment 224. Subsequent covers are nested each within the preceding cover and to accommodate them the abutment 224 will gradually be moved rearwardly by the force exerted by the forming block and the covers on the abutment 224. The extent of the rearward movement of the forming block is determined by engagement of the lever 58 with an adjustable stop screw 237 (Fig. l).

Secured to the holder 226 are side walls 238 (Fig. 1) between which the cover blanks are stacked in nested relation, these walls having forwardly and downwardly inclined top edge portions over which the upper edges of the covers are turned and held in outwardly turned positions by holddown members 240. These members comprise a pair of spaced arms secured. to a shaft 242 (Fig. 10) journaled in a bracket 244 fixed to and extending upwardly from the table 16. The forward ends of the holddown members 240 are turned downwardly at 246 to hold the out-turned edges of the covers against the upper edges of the side plates 238. Normally these holddown members are in the positions illustrated in Fig. 1 but upon rearward movement of the forming block 22 to deliver a formed cover into the stacking station the holddown members are lifted into the positions shown in Fig. 10 so as not to interfere with the delivery of another cover into the stacking station. For this purpose the shaft 242 has an upstanding am 248 through which passes a forwardly extending rod 250 guided for movement in a transversely extending frame member 252 and having its forward end portion arranged for engagement by thesleeve 32 by which the forming block is carried. The rod 250 has a collar 254 engageabie with the forward face of the arm 248 to cause the arm to move rearwardly upon rearward movement of the rod and a second collar 256 limits forward movement of the rod 250 and hence downward movement of the holddown members 240.

Also associated with the table 16 is a gripper 258 arranged to hold the toe portions of the covers down against the forward end of the table 16.. This gripper is pivoted at 26% to a lever 262 an intermediate portion of which is pivoted to a forwardly extending bracket 264 carried by the underside of the table 16. The lower end of the lever 262 is connected to an arm 266 having a slot 268 (Fig. l) through which passes a shaft 270 journaled in brackets depending from the table 16. The shaft 270 carries a cam C72 arranged for engagement with a canrroll 27 carried by the arm 266 whereby upon rotation of the shaft 270, lengthwise movement is imparted to the arm 266 to swing the supporting lever 262 and to move the gripper 258 toward and from the table 16. A spring 276 connected between the lever 262 and one of the brackets carrying-the shaft 270 maintains the cam roll 274 in contact with the periphery of the cam 272. A spring 278 connected between the grip per 258 and the lever 262 urges the gripper 258 down movement.

the axis of movement of the lever 262 but it is desirable that during return movement into gripping relation with .the covers, it moves more nearly vertically onto the .toe ends of the covers, as otherwise it-would tend to ,push the toe ends of the covers rearwardly on the table. To effect .this movement of the gripper, a cam plate 284 is pivoted at 280 to a bracket 282 on the underside of the rearward portion of the table 14. The cam plate 284 has a laterally extending cam 286, as shown in Fig. ,9, which cooperates with a pin 288 extending through the gripper 258 and to one end of which the spring 278 isattached. A-pin and slot connection 290 (Fig. between the cam platen284 and the bracket 282 limits movement of the cam plate about its pivot 288. Upon counterclockwise movement of the lever 262 to move the gripper 258 forwardly out of gripping relation with the covers, the pin .288 engages the undersurface of the cam 286 which will ,be lifted about the pivot 288 during this movement .of the gripper. With the gripper in its forwardmost position thepin 288 clears the forward end of the cam 286 whereupon the cam plate is permitted to move downwardly about its pivot 288 so that upon clockwise movement of the lever 262 to return the gripper to operative position the pin 288 will ride on the top surface of the cam 286 'whichis shapedto hold the gripper above the toe ends of the shoe covers during its return At the latter portion of this movement the pin 288 falls off the cam 286 and the spring 278 snaps the gripper 258 downwardly against the toe ends .of the covers.

The shaft 270 by which motion is imparted to the gripper 258 is operated from the shaft 122 by which the aforedescribed mechanisms for forming the covers are operated. The shaft 122 carries near its outer end a sprocket 291 (Fig. 5) over which passes a chain 292 which also passes over a sprocket 293 carried by a countershaft 294 journaled in the frame of the machine. A second sprocket 295 carried by the countershaft 294 is connected to a sprocket on the shaft 270 (Fig. 1.) by a sprocket chain 296. Thus it will be seen that the operation of the gripper 258 is in timed relation to the mechanisms for forming and sealing coverblanks in the forming station.

Immediately following upward movement of the holddown members 240 when the forming block is moved to carry a newly formed cover into the stacking station, the side portions of the cover carried by the forming block .are spread outwardly, as indicated in Fig. 9. For this purpose a pair of spreaders 298 are moved outwardly engaging the mid portions of the cover to spread them outwardly over the side wallsof the stacking station and a second pair of spreaders 300 engageable with the toe portion of the cover are moved outwardly for the same purpose. The spreaders 298 include forwardly and downwardly inclined portions, as shown in Fig. 12, and are carried by arms 302 pivoted on the screws 24 by which the plates 25 are secured to the top of the forming block near its heel end. The slide carries a pair of pins 310 (Fig. 9) which are received by recesses in the arms 302. The slide 30 is normally urged heelwardly of the forming block to a position in which the spreaders 298 are coextensive with the sides of the forming block. For this purpose a lever 311 pivoted at 312 to one of the plates 25 has a notched end portion in which is received a pin 314 carried by the slide 30. A spring 316 con- .nected between the other end of the lever 311 and a screw threaded into the side of the plate 25 normally urges the lever 31 1 in a counterclockwise direction, as viewed in Fig. 9, thus moving the spreader arms 302inwardlyinto inactive positions.

The forward end of the slide 30 has secured to it a downwardly extending (arm 318 (Fig. 1 2) having a ,forwardly extending portion pivoted to an arm 320 secured to a rearward extension of one .of the spreaders 300. These spreaders are pivoted at 322 to the forwardly extending'tongue portion'67 of the forming block and ,are provided with intermeshing gear segments 324 whereby motion imparted to one will causemovement of the other arm equally but in the opposite direction. Thus, it will be seen that movement-of the slide 30 causes simultaneous movement of the two sets of

spreaders

298, 300 inwardly or outwardly of the forming block, depending upon the direction of movement of the slide.

Mounted above the stacking station is an electromagnet 322 (Fig. 1) the armature of which is connected .to the upper end'of ,a lever 324 (Fig. 10) pivoted to arealwardly extending arm 326 connected to the frame of the machine. The lower end of the lever 324 is pivoted to a forwardlyextending arm 328 the forward end of which passes through, and is guided for movement by, aplate 329. With the forming block .22 in its rearmost-position in the stacking station, as shown by Fig. 10, the rearward end of the slide 30, which has an upturned portion, is arranged to be engaged by the forward end of the arm 328 upon clockwise movement of the lever 324 by energization of the electromagnet. Carried by the frame member 252 is a microswitch 330 having a forwardly extending switch button arranged to be operated 'by a screw 332 carried by an arm 334 secured to the bracket 26. The screw 332 is preferably adjusted so that the circuit through the microswitch is closed to energize the electromagnet 322 immediately after the hold-down members 240 have been raised, as heretofore explained. Immediately upon energization of the electromagnet the arm 328, connected to the lower end of the lever 324,

.is moved forwardly moving the slide 30 forwardly against the action of the spring 316 (Fig. 9) causing outward movement of the

spreaders

298, 300 into the positions shown in Fig. 9 and spreading the cover away from the forming block.

The table 16 carries a forwardly extending bracket 336 (Fig. 9) which has a portion arranged to overlie the tab portions T of the cover as the toe portions are spread outwardly by the spreaders 300. It will also be shown in Fig. 2, is placed on the table 14 below the forming block with the throat portion abutting a shoulder 339 (Fig. 10) which rests on the work table when :the forming block is in'the forming station, the tongue portion 67 being spaced sufliciently above the table to permit the toe end of the blank to be located therebeneath. The shaft 122 is turned in a clockwise direction, as viewed in Fig. 1, whereupon the forming plates 64, .65 are moved from their horizontal positions, as shown in Fig. 6, upwardly to turn the sides of the blank and hold them against the sides of the forming block. As movement of the shaft 122 continues the arm 70 (Fig. 8), carrying the slotted plate 106, moves inwardly until it lies against the forming plate 64 thus turning the heel portion atone side of the cover blank inwardly against the heel-end of the forming block. Following this the plate 72 ,moves against its forming plate 65 and the fingers carry the the plate 168 (Figs. 2 and 3) is moved upwardly whereupon the wires 172 move the tab portion T past the pressing block 178 whereby the tab is partially folded over and the unfolded portion is moved into engagement with the heating block 180. Immediately following this the cam 126 (Fig. 2) on the shaft 116 operates the microswitch 128 to energize the solenoid 130. Energization of this solenoid causes downward movement of the heating block 154 to seal the overlapped portions of the heel end of the cover together and also causes downward movement of the pressing block 178 to complete the folding of the tab portion and to hold it in firm contact with the heating block 180 so that the two plies of the tab are heat sealed together. Motion of the drive shaft 122 may be arrested for a short interval, if necessary, to complete the sealing operation by the heaters and further movement of the shaft will return the parts after first deenergizing the solenoid 130, to their original positions. It will be understood at this time that the plate 168 (Fig. 3) will remain in its vertical position with the wires 172 held between the plies of the tab but not sealed therein because of the recesses in the presser block 178 and in the heating block 180. It will also be understood that if desired a timer may be employed to maintain the solenoid 130 energized for a suflicient length of time and that the

cams

102, 104 may be so designed that interruption of rotation of the drive shaft 122 is not necessary, the cams providing a dwell for the duration of the heat sealing portion of the cycle.

After the cycle of operations of the forming station has been completed the forming block is moved by the handle 40 rearwardly to carry the formed cover into the stacking station. The holddown members 240 are raised just prior to the completion of the rearward movement of the forming block and the gripper 258 is retracted after which the solenoid 322 is energized to separate the

spreaders

298, 300 to spread the newly formed cover outwardly of the forming block and over the sides 238 of the receptacle forming the stacking station. The forming block is now returned to the forming station and at the beginning of its return movement the solenoid 322 is deenergized whereby the spreaders are withdrawn into the forming block, the holddowns 240 are again moved downwardly to hold the outwardly turned sides of the newly formed cover in outwardly extending positions and the gripper 258 returns to gripping position in contact with the toe portion of the newly formed cover.

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 forming protective covers for shoes from fiat blanks, a work support, a forming block on the support, said forming block having a tongue portion in slightly spaced relation above said support whereby a cover blank may be placed on the support with its toe portion underlying the tongue portion of the forming block and the sides and heel portions extending along opposite sides of the forming block, means for simultaneously turning the side portions of the blank upwardly into contacFivith opposite sides of the forming block with the heel portions projecting beyond the heel end of the block, means operable automatically after the side portions have been thus turned for turning the heel portions of the heel blank inwardly into overlapping relation, and means for bonding together the overlapped heel portions of the blank.

2. In a machine for forming protective covers for shoes from flat blanks, a work support, a forming block on the support, said forming block having a tongue portion in slightly spaced relation above said support whereby a cover blank may be placed on the support with its toe portion underlying the tongue portion of the forming block and the sides and heel portions extending along opposite sides of the forming block, means for simultaneously turning the side portions of the blank upwardly into contact with opposite sides of the forming block with the heel portions projecting beyond the heel end of the block, means operable automatically after the side portions have been thus turned for turning the heel portions of the heel blank inwardly into overlapping relation, means for bonding together the overlapped heel portions of the blank, and means for moving the forming block lengthwise of itself with the formed shoe cover to a position remote from said support.

3. In a machine for forming protective covers for shoes from flat blanks, a work support, a forming block on the support, said forming block having a tongue portion in slightly spaced relation above said support whereby a cover blank may be placed on the support with its toe portion underlying the tongueportion of the forming block and the sides and heel portions extending along opposite sides of the forming block, means for simultaneously turning the side portions of the blank upwardly into contact with opposite sides of the forming block with the heel portions projecting beyond the heel end of the block, means operable automatically after the side portions have been thus turned for turning the heel portions of the heel blank inwardly into overlapping relation, means for bonding together the overlapped heel portions of the blank, and means for depositing the formed covers in stacked relation in a station remote from the forming block.

4. In a machine for forming protective covers for shoes from flat blanks, means for turning the side portions of the blanks into generally parallel relation, and means for turning the heel portions of the sides of the blanks inwardly into overlapping relation and bonding together the overlapped portions, said last-named means comprising a plate movable to turn the heel end portion of one of the sides inwardly, said plate having slots extending in wardly from the leading edge thereof, a member having fingers receivable in said slots and arranged to turn in the heel end portion of the other side into overlapping relation with said first turned-in portion and with the plate, means for withdrawing the plate from between the turned-in portions, and means for applying heat to the turned-in portions.

5. In a machine for forming protective covers for shoes from flat blanks, a vertically disposed forming block having parallel side Walls against which the sides of a blank from the throat portion rearwardly may be turned to enable joining the heel end portions of the blank, a plate at each side of the forming block movable from a horizontal blank supporting position to a vertical position, means for thus moving the plates, means associated with the plates for turning the heel end por tions of the blank into overlapping relation against the end of the forming block, means for applying heat and pressure to the overlapped end portions of the blank, and means for simultaneously folding an extension of the blank to form a tab of double thickness.

6. In a machine for forming protective covers for shoes from flat blanks, a vertically disposed forming block having parallel side walls against which the sides of a blank from the throat portion rearwardly may be turned to enable joining the heel end portions of the blank, a plate at each side of the forming block movable from a horizontal blank supporting position to a vertical position, means for thus moving the plates, means associated with the plates for turning the heel end portions of the blank into overlapping relation against the end of the forming block, means for applying heat and pressure to the overlapped end portions of the blank, means for simultaneously folding an extension of the blank to form a tab of double thickness, and means for applying heat and pressure to the overlapped end portions of the 'blank and to the double thickness tab.

7. In a machine for forming protective covers for shoes from flat blanks of thin plastic material, mechanism for turning the sides of a blank upwardly and for closing 11 the .heel'end of the blank, means for transferring the cover into nested relation with previously formed covers at a stacking station, and means associated with said stacking stationtfor holding the cover in inverted posi- .to -.a stacking station, and means associated with said stacking station for-holding the :cover in inverted position with !the upper marginal vportions and .the tabs turned outwardly to facilitate nesting and subsequent separation ,ofsuccessively formed covers.

,9. -In a shoe cover forming machine, a stacking sta .tion tfor receiving formed covers ,in inverted positions, means forvfeeding covers oneat a time into the stacking station, means for holding the upper margins of thelcovers in outwardly ,turned positions in the stacking station, and

means operative during the feeding of a blank into the stacking station for retracting the :holding means and spreading the margins of the cover outwardly into contact with the cover in which it is nested.

10. in (a machine ,for forming protective covers vfor shoes from flat blanks, :a vertically disposed forming block-means for supportinga cover blank with the side portions extending alongand the heel portions extending slightly beyond said forming block comprising a pair of "plates pivoted about parallel vaxes extending along the .lowerportionofthe forming block, arms pivoted to said .plates about laxes normal to the first-mentioned waxes, spring means normally urging the free ends of said arms away from said plates, means acting through said arms to move the platesinto vertical positions alongside the forming blocktand:meanscarried bysaid arms for turning the heel portions of the'blank around the end of the forming block in overlapping relation.

11. In a .machine for vforming protective covers for shoes, ,from flat blanks, .a vertically disposed forming block, means for supporting a cover blank with the side ,portions extending along vand the heel portions extending slightly beyond said forming block ,comprisinga pair of ,plates pivoted about parallel axes extending along the lower portionof the forming block, arms pivoted to said plates about axes normal to the first-mentioned axes,

spring means normally urging the free ends of said arms away from said plates, means acting through said arms to move the plates :into vertical positions alongside the forming block, and means carried by said arms for turning the .heel portions of the :blankaround the endof theforming block in overlapping relation, said last-named means comprising a slotted .plate carried by the freeend of one of said varms ,and a plurality of fingers carried by the free endof ,the other arm arranged to be received by the slots in the slotted plate upon movement of the arms into engagement with the firstsnamed plates when the plates-arein their verticalpositions.

.12. In va machine for ,forming protective .covers for shoes from flat blanks, :a vertically disposed forming block,rm.eans for Supporting vacover blank with the side portions .extending along and the heel :porti'ons extending slightly beyond said forming block comprising a pair of plates pivoted about parallel axes extending along the lower ,portion of the forming .block, arms pivoted to said plates about axes normal to the first-mentioned axes, spring means normally urging the free ends of said;arms away from said .plates, means acting through said arms to move the plates into vertical positions alongside the forming block, and means carried by said arms for turning the ,heel portions of the blank around the end of the forming block in overlappingrelation,:saidlast-named means comprising a slotted plate carried by-the free end of -.One of said arms and a plurality of fingers carried by the free end-ofsthe other arm arranged to be received by the slots in the slotted plate upon movement of the arms into engagement with the first-named plates when the plates are in their vertical positions, said 'mov ing means being arranged first to move the arm carrying the slotted plate into engagement with its associated plate and then to move the other arm to carrytthe fingers into register with the slots to retract the first-mentioned arm whereby the overlapped portions of the heel end of the blank are held wholly by the fingers, .and means for applyingheat and pressure to theloverlapped portions of the blank.

References Citedin the file-of this patent UNITED STATES PATENTS 1,881,670 Kenney Oct. 11, 1932 2,591,383 Spalding Apr. 1, 1952 2,746,067 Paulsen May'22, 1956