US3325841A - Method and apparatus for clamping the heel portion of a shoe assembly - Google Patents

Description

June 20, 1967 H. M. LEONHARDT 3,325,841

METHOD AND APPARATUS FOR CLAMPING THE HEEL PORTION OF A SHOE ASSEMBLY 5 Sheets-Sheet 1 Filed Feb. 15, 1965 FIG-l //V 15 N 70/? Horsf M Leon/20rd) By MW ATTORNEY June 20,1967 H. M. LEONHARDT 3,325,841

METHOD AND APPARATUS FOR CLAMPING THE HEEL PORTION OF A SHOE ASSEMBLY Filed Feb. 15, 1965 5 Sheets-Sheet 2 -78 Q 0 O o 0 e43 a0 55 98 o F/Gr5 Me 1967 H. M. LEONHARDT 3,325,841 METHOD AND APPARATUS FOR CLAMPING THE HEEL PORTION OF A SHOE ASSEMBLY Filed Feb. 15, 1965 5 Sheets-Sheet 5 June 26, 1957 H. M. LEONHARDT 3,325,841

METHOD AND APPARATUS FOR CLAMPING THE HEEL PORTION OF A SHOE ASSEMBLY 5 Sheets-Sheet 4 Filed Feb. 15, 1965 FIG: 8

June 2%, 1967 H. M. LEONHARDT 3,325,841 METHOD AND APPARATUS FOR CLAMPING THE HEEL PORTION OF A SHOE ASSEMBLY Filed Feb. 15, 1965 5 Sheets-Sheet 5 Patented June 20, 1967 3 325,841 METHQD AND APPARATUS FOR CLAMPING THE HEEL PORTION F A SHOE ASSEMBLY Horst M. Leonhardt, Randolph, Mass, assignor to Jacob S. Kamhorian, West Newton, Mass. Filed Feb. 15, 1965, Ser. No. 432,515 Claims. (Cl. 12-142) This invention relates to the clamping of the heel portion of a shoe upper against a last in an improved manner so that the clamped upper portion is stretched snugly about the heel portion of the last including the difficult to reach reentrant portions of the last.

In the illustrative embodiment of the invention, the upper is clamped against the last by a heel clamp preparatory to wiping the heel portion of the upper against an insole located on the last bottom. The heel clamp takes the form of a pad that has legs located on opposite sides of the last. The pad legs are initially spaced from the last and a drive for the pad is so connected to the pad as to first move the pad legs inwardly in directions that have a component of movement extruding from the heel to the toe of the last and then move the pad legs inwardly in directions that are substantially at right angles to the longitudinal center line of the last. The last, upper and insole constitute a shoe assembly. The invention is shown as being incorporated in the heel seat lasting machine disclosed in pending application S.N. 353,462 filed Mar. 20, 1964.

In the accompanying drawings:

FIGURE 1 is a side elevation of a lasting machine that incorporates the invention;

FIGURE 2 is a view taken on the line 2-2 of FIG- URE 1;

FIGURE 3 is a side elevation of a portion of the machine in which the heel clamp is mounted;

FIGURE 4 is a view taken on the line 4-4 of FIG- URE 3;

FIGURE 5 is a view taken on the line 5-5 of FIG- URE 3;

FIGURE 6 is a view taken on the line 6-6 of FIG- URE 4;

FIGURE 7 is a view taken on the line 7-7 of FIG- URE 4;

FIGURE 8 is a top view of the shoe assembly placed in the machine at the beginning of the machine cycle wherein he forepart portions of the upper margin are gripped by pincers;

FIGURE 8A is a view taken on the line 8A-8A of FIGURE 8;

FIGURE 9 is a top view of the shoe assembly showing the movement of the heel clamp against the heel portion of the last;

FIGURE 9A is a view taken FIGURE 9;

FIGURE 10 is a top view of the shoe assembly showing heel lasting wipers of the machine at the beginning of their wiping stroke;

FIGURE 11 is a view similar to FIGURE 10 that shows the wipers in an intermediate position of their wiping stroke;

FIGURE 12 is a view similar to FIGURE 10 showing the wipers at the end of their wiping stroke; and

FIGURE 13 is a schematic representation of a portion of the control circuit of the machine.

Referring to FIGURE 1, the machine includes a frame It} that comprises a base 12 and a housing 14. The machine is tilted about 30 degrees to enable the operator to have ready access thereto. For ease of explanation, the direction of the base 12 will be referred to as horizontal and the direction of the housing 14 will be referred to as vertical. In operating the machine, the operator stands to on the line 9A-9A of the right of the machine as seen in FIGURE 1, and parts moving toward the operator (left to right in FIGURE 1) will be described as moving forwardly while parts moving away from the operator (right to left in FIGURE 1) will be described as moving rearwardly. The housing 14 includes a flange 16 that is secured to the base 12 by bolts 18. A hanger 20, bolted to the bottom of the housing 14, has a vertically extending air operated motor 22 secured thereto. The piston rod (not shown) of the motor 22 is connected to a post 24 that is slidably mounted in the housing 14 and that extends upwardly of the housing. A shoe supporting platform 26 has a socket (not shown) in its bottom which receives the top of the post 24, and the platform and post are connected by a pin 28. A horizontally extending base 30 is mounted on the platform 26. The rear of the base 30 has a framework 32 extending upwardly thereof. A toe rest 34 and two pincers 36 are incorporated in the framework 32 (see FIGURES 8 and 8A). The platform 26 has a base 38 secured thereto that comprises a tubular portion 40. A hollow column 42 is seated on and locked to the tubular portion 40 and a hollow sleeve 44 is screwed into the column 42 and extends upwardly thereof. A last pin 46 and a shoe assembly supporting plate 48 are mounted on the sleeve 44 (see FIG- URE 8A). The plate 48 has a flat upper surface 56 and a hole 52 through which the last pin 46 extends.

As shown in FIGURES 1 and 2, a head 54 is mounted on the frame 10 rearwardly of the framework 32 and the last pin 46. The head 54 and gi bs 56 that are bolted to the head form a guideway that receives a main slide plate 58. A cover 60 is spaced above the plate 58 at its forward end. The cover 60 is connected to the plate 58 by means of spacers 62. The plate 58 has a lug 64 (FIGURES 3 and 5) depending therefrom that is bolted to the piston rod 66 of an air actuated motor 68, and the motor 68 is connected to a hanger 70 depending from the frame 10 by a pin 72. A pair of spaced side struts 74 and 76 are respectively pivoted to the hanger 74} on pins 78 and 80 and extend forwardly of the hanger alongside the motor 68. A center strut 82 is fastened to the hanger 70 between the pins 78 and 80 and extends forwardly between the struts 74 and 76. The lug 64 has a bracket 84 bolted thereto on which a pair of spaced tangs 86 and 88 are pivoted. The tangs extend rearwardly of the lug 64 with the tang 86 located between the struts 74 and 82 and the tang 88 located between the struts 76 and 82. A pair of plates 90 and 91 are secured to the center strut 82 and respectively overlie and underlie the tangs 86 and 88, to maintain the tangs at the same level as the strut 82. A pair of straps 92 and 93 are respectively pivoted at their inner ends to the top and bottom of the forward end of the side strut 74 by a pin 94. The straps 92 and 93 extend laterally of the struts 82 and 76 and the tangs 86 and 88 between spaced abutments 96 that are located on the strut 76. The outer ends of the straps are pivotally connected by a pin 98 to a link 100. The link 100 is pivoted to a limb 102 that is secured to the piston rod 104 of an air actuated motor 106. The motor 106 is pivoted to the hanger 70. The link 100 has a cam surface, not shown, that is eccentric with respect to the axis of the pin 98.

From the foregoing it can be seen that an actuation of the motor 106 to project the piston rod 104 out of the motor in a leftward direction as seen in FIGURE 5 will swing the link 100 clockwise (FIGURE 5) about the axis of the pin 98 and cause the eccentric cam surface on the link 100 to jam the struts 74, 82 and 76 and the tangs 86 and 88 against each other. A retraction of the piston rod 104 into the motor 106 causes the link 100 to swing counterclockwise and thus free the tanks to slide between the struts.

As shown in FIGURE 4, a pair of air actuated drive motors 108 are swingably mounted on the plate 58 on pivot pins 110. Each motor 108 has a piston rod 112 that is pivtoally connected to a lever 114 by a pivot 116. The levers 114 have legs 118 extending forwardly and divergently from the pivots 116 and legs 120 extending inwardly toward each other from the pivots 116. The legs 120 are pivotally connected by pivots 122 between flanges 121 and 123 at the forward end of a slide beam 124. The beam 124 is slidably mounted between walls 126 formed in the slide plate 58 (FIGURE 6). A rod 128 is pinned to the beam 124 and extends rearwardly thereof through a bracket 130 that is bolted to the slide plate 58 (FIGURE 4). The rear end of the rod 128 is secured to a bar 132 that is slidably guided in the slide plate 58 and a valve actuator 134 is located at the rear end of the bar 132 (FIGURE 3). A valve 136, mounted on a housing 138 secured to the rear end of the slide plate 58, has a valve stem 140 depending therefrom that is in alignment with the valve actuator 134. A compression spring 142, coiled about the rod 128 between the beam 124 and the bracket 130, yieldably urges the beam forwardly to a position where the contiguous surfaces of the lever legs 120 about each other pursuant to the swinging of the levers about the pivots 122.

A U -shaped clamping pad 144 is provided that is made of an expandable, deformable material such as rubber (FIGURES 3, 4, 6 and 7). The pad 144 has a bight 146 and a pair of legs 148 extending forwardly of the bight. The pad has a cavity 150- (FIGURE 9A) into which. pressurized fluid such as air may be forced by way of a line 152 (FIGURES 2 and 7) to expand the inner walls of the pad for reasons described below.

As seen in FIGURE 7, a pair of vertically spaced headed pins 154 extend outwardly of each pad leg 144 adjacent its forward end. A pair of plates 156 and 158 (FIGURE 4) that are welded to each other at their forward ends have slots 160 therein that receive the shanks of the pins 154 whereby the plates 156 and 158 are located between the heads of the pins and the outer peripheries of the pad legs 148. Each of the plates 158 has an offset portion 162. The ends of a back-up member, that takes the form of a strap 164 made of a flexible material such as corded rubber, are inserted between the plates 156 and the offset portions 162 and are riveted thereto. The strap 164 extends about the outer periphery of the pad 144. A lug 166 extends outwardly of each offset portion 162. A spring wire 168 has its midportion extending about the lug 166 and each of its ends entwined about a pin 154 in order to resiliently urge the pins 154 against the bases of the slots 160. The bight of the strap 164 extends between and is riveted to an inner plate 170 and a pair of outer plates 172. The outer plates 172 have flanges 174 that are slidably received for vertical movement in a bracket 176 that is secured to the flanges 121 and 1237 A screw 178, threaded into the bracket 176 and bearing against the bases of the flanges 174, serves to ad-- just the position of the plates 172 in the bracket 176. A tank 180 (FIGURE 6) extending downwardly from the plate 170 and tanks 182 (FIGURES 2 and 7) extend ing downwardly from the plates 156 underlie and support the pad 144. The plates 156 and 158 thus serve as mounts for the pad legs 148 and the plates 170 and 172 thus serve as mounts for thepad bight 146.

A link 184 is pivoted to each lever leg 118 by a pivot 186 and extends forwardly and inwardly therefrom. The forward end of each link 184 is pivoted. to a lug 166 by a pin 188. A bar 190 is adjustably mounted in each lever leg 118 outwardly of its associated link 184 by set screws 192 extending through elongated slots 194 in the bars and threaded into the lever legs 118.

A wiper supporting slide plate 196 (FIGURE 2) is slidably rnounted for forward and rearward movement on shoulders 198 on the spacers 62 above the main slide plate 58. Wiper cams 200, resting on the plate 196 immediately below the cover 60, have wipers 202 (FIGURE 10) mounted thereon. The wipers have side surfaces 204 that diverge forwardly from a vertex 206. Wiper drive means that include an air actuated motor 207 (FIGURE 1) and that are disclosed more fully in the aforementioned application Ser. No. 353,462 are provided in the machine to drive the wipers in the manner described below.

Referring to FIGURES l and 2, the head 54' has a cover 208 that overlies the cover 60 and supports a holddown unit 210. The hold-down unit includes a slide 212 that is constrained for forward andrearward movement on the cover 208 by gibs 214 bolted to the cover. As shown more clearly in the aforementioned application Ser. No. 353,462, a hold-down holder 216 is pivoted to the slide 212 for swinging movement in a vertical plane. The hold-down holder 216 has a downwardly projecting hold-down 218 mounted thereon. An air operated motor 220 is connected to the slide 212 to effect forward and rearward movement of the slide and an air operated motor 222 is mounted on the slide 212 in such a manner as to effect heightwise movement of the hold-down 218. i

In the idle condition of the machine, the post 24 is maintained by the motor 22 in a lowered position to maintain the last pin 46, the shoe assembly supporting plate 48, the toe rest 34 and the pincers 36 in a lowered position, the piston rod 66 is retracted into the motor 68 to maintain the main slide plate 58 in a rearward position, the piston rod 104 is retracted into the motor 106 to enable the tangs 861 and 88 to be slidable between the struts 74, 82, and 76, the piston rods 112 are retracted into the motors 108 to maintain the pad 144 in an open position with the lever legs 120 moving rearwardly about the pivots 122 and abutting each other and the inner ends of the bars 190 spaced from the links 184 as indicated in FIGURE 4, there is no pressurized fluid in the line 152 so that the pad 144 is deflated, the wiper supporting slide plate 196 is in a rearward position with respect to the main slide plate 58 and the wipers 202 are in a rearward open position as indicated in FIGURE 10, the slide 212 and hold-down 218 are maintained by the motor 220 I in a rearward out-of-the-way position and the hold-down 218 is maintained by the motor 222 in a relatively lowered position.

Although the machine has general utility in stretching an upper over a last and wiping the heel of the upper against an insole, it is herein disclosed as performing the method disclosed in Patent No. 3,144,670 wherein the heat softenable counter disclosed in said patent and in application Ser. No. 134,641 filed Aug. 29, 1961, now abandoned, is utilized.

A shoe upper 224 (FIGURES 8 and 8A) is provided having a liner 226 united thereto at the heel end of the upper. A counter 228 is inserted between the upper 224 and the liner 226 with an exposed portion of the counter extending upwardly of the upper edge of the liner and a concealed portion lying between the liner and the upper. The counter is made of a homogeneous thermoplastic material and has the characteristic of being stiff and rigid at ambient temperatures, of becoming soft and flaccid when heated above a predetermined temperature and of reverting to its stiff and rigid state when cooled back to ambient temperatures. The counter is coated on both of its surfaces with a thermoplastic adhesive which becomes sticky or tacky when heated above said predetermined temperature and reverts to its normal rigid, cohesive condition when cooled below the predetermined temperature back to ambient temperature.

The counter, upper and liner assembly is heated to a temperature suflicient to render the counter soft and flaccid. This may be done in apparatus similar to that disclosed in Patent No. 3,1115,651. This assembly is then draped about a last 230 (FIGURES '8 and 8A) having an insole 232 mounted on its bottom to form a shoe assembly. The shoe assembly is placed bottom-up on the shoe assembly supporting plate 48 with the last pin 46 entering the conventional last pin hole in the last. The toe portion of the upper and last is supported on the toe rest 34 and the forepart portions of the upper margin are inserted between the jaws of the pincers 36. At this time the upper end of the liner 226 is substantially level with the insole 232 and the upper surfaces of the counter 228 and upper 224 at the heel end of the last extended above the insole as indicated in FIGURE 8A.

The machine control disclosed in the aforementioned application Ser. No. 353,462 is now actuated by the operator to cause the pincers 36 to grip the forepart portions of the upper margin. At this point the operator may inspect the work to see if the pincers are properly gripping the upper margin. If they are not, he may cause the pincers to open. If the upper margin is being properly gripped by the pincers, the pincers are caused to move forwardly to thereby horizontally stretch the upper in the direction of the toe of the last and cause a firm wrapping to the upper about the heel of the last and a tension force on the counter to start to mold it to the shape of the last. At this point the operator may again inspect the work and return the machine parts to their original position if the upper is not being properly engaged by the pincers and stretched about the heel of the last.

The operator, assuming he is satisfied with the condition of the work in the machine, now actuates the machine control to enable the machine to go through the rest of its cycle automatically. The motor 220 is thereby actuated to move the hold-down unit 210 forwardly to move the hold-down 218 from its out-of-the-way position to a working position above the shoe and last bottom. Prior to this time in the machine cycle the hold-down had been in its rearward out-of-the-way position so as not to interfere with the placement of the shoe assembly on the last pin 46 and plate 48 and also so as not to interfere with the operators observing whether the upper was properly gripped by the pincers 36 and whether the upper was properly stretched about the heel of the last as a result of the forward stretching movement of the pincers.

Now the motor 22 is actuated to raise the post 24 together with the last pin 46, the last supporting plate 48 and the toe rest 34 and pincers 36 until the insole 232 bears against the hold-down 218. The bottom of the hold-down is located slightly below the level of the undersurfaces of the wipers 202 so that the raising of the shoe assembly by the actu "on of the motor 22 brings the insole to a level that is slightly below the level of the bottom of the wipers regardless of the height of the last or the thickness of the insole and clamps the shoe assembly between the plate 48 and the hold-down 218.

After this, a valve 234 (FIGURE 13) in the control system is shifted to cause pressurized air to pass from the source through a line 236 and a line 238 to the motor 68 to cause the motor 68 to move the main slide plate 53 forwardly and thereby move the clamping pad 144 and wipers 202 forwardly from their out-of-the-way position until the bight 146 of the pad 144 engages the heel end extremity of the shoe assembly as shown in dotted lines in FIGURE 9. The engagement of the pad bight with the shoe assembly causes the beam 124, rod 128 and bar 132 to move rearwardly with respect to the plate 58 until the valve actuator 134 shifts the valve stem 140 of the valve 136. The shifting of the valve stem 140 causes ressurized air to pass from the valve 234, through a line 240, the valve 136 and a line 242 to the motor 106 to actuate this motor to jam the struts 74, 82 and 76 and the tangs 86 and 88 against each other and thus stop the forward motion of the slide plate 58 and lock the slide plate in position. Prior to the shifting of the valve 234 pressurized air had passed from the valve 234 through a line 244 to the motor 68 to cause this motor to maintain the slide plate 58 in its rearward position and had passed from the valve 234 through a line 246 to the motor 106 to maintain the motor 106 in a condition that enabled the tangs 86 and 88 to be slidable between the struts 74, 82, and 76. During the rearward movement of the beam 124 the lever legs 118 swing inwardly to some extent about 6 the pivots 122, but not enough to cause any substantial engagement of the pad legs 148 with the shoe assembly.

The main slide plate had been maintained in its retracted out-of-the-way position up to this time so as to enable the operator to inspect the shoe assembly during the gripping of the upper margin by the pincers 36 and the horizontal stretching movement of the pincers without interference by the heel clamp 144 and the wipers 202. In addition, the maintenance of the heel clamp and the wipers in their out-of-the-way position enables the motor 22 to raise the shoe assembly without interference with the heel clamp and wipers. By having the forward movement of the main slide plate 58 terminated and the plate locked in position in response to engagement of the bight of the heel clamp with the heel end of the shoe assembly, it is assured that the heel clamp and wipers will be positioned adjacent the shoe assembly for the subsequently performed heel clamping and wiping operation regardless of the location of the heel end of the shoe assembly.

After the locking of the main slide plate 58, the pincers 36 are caused to move vertically and thus apply an upward tension to the upper margin at its forepart portions to thereby stretch the upper tightly on the last and assemble it in proper position for the subsequent heel seat lasting operation. Since the shoe assembly is clamped at this time between the last supporting plate 48 and the hold-down 218, upward movement of the pincers will not shift the last 230.

The motors 108 are now actuated to cause the piston rods 112 to swing the levers 114 about the axes of the pivots 122 in a direction to move the lever legs 118 inwardly toward each other. This causes the inner walls of the pad legs 148 to engage the heel portions of the upper in regions that extend in the direction of the toe from the heel end extremity of the upper and press these portions against the last. During the early portion of the inward swinging movement of the lever legs there is relative swinging movement of the links 184 with respect to the lever legs 118 about the axes of the pivots 186 and relative swinging movement of the links 184 with respect to the lugs 166 about the axes of the pins 188. This swinging movement of the links 184 is such that, as seen in FIGURE 4, the upper link 184 swing clockwise about its pivot 186 and the lower link 184 swing counterclockwise about its pivot 186. Partway through the inward swinging movement of the lever legs 118 the bars 190 engage the links 134 and thereby preclude any further relative movement between the lever leg 118, the links 184 and the lugs 166. As a result, during the period that the links 184 have relative swinging movement with respect to the lugs 166 the lugs have movements imparted to them that have components extending in a heel to toe direction thus imparting a stretching of the inner walls of the pad legs in a heel to toe direction as they engage the upper. During the period that the bars 190 are in engagement with the links 184, these heel to toe components of movements are terminated; The effect of this is that at the beginning of the engagement of the inner walls of the pad legs 148 with the upper 224 they tend to push the engaged portions of the upper away from the heel as well as forcing the engaged upper portions inwardly against the last to thereby further stretch the heel portion of the upper and the counter 228 about the heel portion of the last and then the pad legs press the engaged upper portion in directions that are substantially norm-a1 to the longitudinal center line of the last to ensure that the upper is tightly pressed against the last, particularly in the reentrant portions of the last indicated by the letters A in FIGURE 9. During the aforesaid movements of the pad 144, the strap 164 resists outwardly directed pressures of the pad and thus enhances the inwardly directed forces applied by the pad.

Concomitantly with the actuation of the motors 108, pressurized fluid (preferably air) is caused to enter the pad cavity through the line 152 to expand the inner wall of the pad 144 against the shoe assembly. The clamping pad 144 acts to provide a compression molding force on the counter to further mold it to the shape of the last as well as clamping the upper for the subsequent wiping operation. By having the bight 146 of the pad 144 engage the shoe assembly and following this with a progressive engagement of the pad legs 148 with the shoe assembly in the manner described above, there is provided an initial contact of the pad at the heel end of the shoe assembly and then a progressive engagement of the pad along the sides of the shoe assembly extending forwardly of the heel to ensure a smoothening out of any wrinkles there may be in the upper and a smooth firm clamping of the upper against the last. The parts now assume the position shown in solid lines in FIGURE 9 and in FIGURE 9A.

After the heel of the shoe assembly is clamped by the inflated clamping pad 144, the wiper driving means, including the motor 207, is actuated to cause the Wipers 202 to move through a wiping stroke. First the wiper supporting slide plate 196 is caused to move forward to translate the wipers forwardly from the FIGURE 10 to the FIG- URE 11 position without the wipers moving inwardly about the vertex 206 so that only the bight of the wiper side surfaces 204 at and adjacent the vertex 206 cross over the last to wipe the upper and counter margins at and adjacent the heel of the last down upon the insole, and the forwardmost portions of the wiper side surfaces 204 do not engage the upper. The wipers are next caused to swing inwardly about the vertex 206 from the FIGURE 11 to the FIGURE 12 position without any forward translatory movement to cause the forwardmost portions of the wiper side surfaces 204 undersurfaces of the wipers to cross over the last and wipe the upper and counter margins upon the insole between the general area of the breastlines of the upper and the portion of the upper engaged by the wipers during the translation of the wipers. At about the time the pronged portions of the wipers engage the upper, the pincers 36 are opened to release the forepart portions of the upper margin.

Towards the end of the inward movement of the wipers 202, the motor 222 is actuated to raise the hold-down 218 so that the motor 22 applies pressure by the shoe assembly directly against the wiper bottoms. At the same time pressurized air under higher pressure than had heretofore entered the motor 22 now enters the motor 22 tocause the shoe assembly to be forced against the wiper bottoms under relatively high bedding pressure. At the conclusion of the wiping stroke the parts are in the position shown in FIGURE 12.

After the wipers have concluded their wiping stroke, they remain in position above the insole with the motor 22 providing bedding pressure on the now wiped upper and counter margins for a predetermined time interval that is sufficient to enable the counter to cool sufficiently to revert to its rigid condition and to enable the adhesive on the counter to cool sufficiently to effect a permanent bond between the upper margin and the insole 232 and between the upper 224 and the liner 228. At the end of this predetermined time interval the machine control enables the machine parts to return to their idle positions and the shoe assembly is released from the machine.

I claim;

1. A method of clamping the heel portion of a shoe assembly, wherein said assembly includes a last having an upper mounted thereon, comprising: maintaining the shoe assembly stationary providing a clamping pad having a bight and a pair of legs extending forwardly of the bight on opposite sides of the bight; locating the pad in a stationary position with the bight in engagement with the heel end of the shoe assembly and the legs extending outwardly of the heel of the shoe assembly on opposite sides thereof; and thereafter causing the legs to move inwardly to bear against the heel portion of and prongs (not shown) on the 8. the shoe assembly by so moving the legs that initially each leg moves in a direction having a component of movement extending from the heel to the toe of the shoe assembly and then each leg moves in a direction that is substantially at right angles to the longitudinal center line of the shoe assembly.

2. A heel clamping mechanism for clamping the heel portion of a shoe assembly, wherein-said shoe assembly includes a last having an upper mounted thereon, comprising: means for maintaining the shoe assembly stationary a clamping pad having a bight and a pair of legs extending forwardly of the bight on opposite sides of the bight; means for locating the pad in a stationary position with the bight in engagement with the heel end of the shoe assembly and the legs extending outwardly of the heel of the shoe assembly on opposite sides thereof; drive means actuable to thereafter move the legs to bear against the heel portion of the shoe assembly; and joining means connecting said drive means and said legs,

said joining means being so constructed and arrangedthat the actuation of the drive means initially causes each of said legs to move in a direction having a component of movement extending from the heel to the toe of v the shoe assembly and then causes each of said legs to move in a direction that is substantially at right angles to the longitudinal center line of the shoe assembly.-

3. A heel clamping mechanism, for clamping the heel portion of a shoe assembly, wherein said shoe assembly includes a last having an upper mounted thereon, comprising: a clamping pad having a bight and a pair of legs extending forwardly of the bight on opposite sides of the bight exteriorly of the shoe assembly, said pad legs being adapted to move inwardly towards each otherin a prescribed plane to bear against the heel portion of the shoe assembly; a lever leg located outwardly of each pad leg; means mounting each lever leg for swinging movement about an axis that is transverse to said prescribed plane; means for initially maintaining the lever legs and the pad legs in an outer position; a link extending forwardly and inwardly from each lever leg to its associated pad leg; means pivotally connecting the rears of the links to the lever legs about axes that are parallel to the first mentioned axis; means pivotally connecting the fronts of the links to the pad legs about axes that are parallel to the first mentioned axis; a bar secured to each lever leg outwardly of its associated link so that each bar is spaced from its associated link when the lever legs and pad legs are in said outer position; and drive means operative to swing the lever legs inwardly about their axes; whereby the pivotal connections between the links, the lever legs and the pad legs causes each of the pad legs to move in a direction having a component of movement extending from the heel to the toe of the shoe assembly until the bars engage the links after which each of the pad legs moves inwardly in a direction that is substantially at right angles to the longitudinal center line of the shoe assembly.

4. A heel clamping mechanism, for clamping the heel portion of a shoe assembly, wherein said shoe assembly includes a last having an upper mounted thereon, comprising: a clamping pad having a bight and a pair of legs extending forwardly of the bight on opposite sides of the bight exteriorly of the shoe assembly, said pad legs being adapted to move inwardly towards each other in a prescribed plane to bear against the heel portion of the shoe assembly; a leg mount connected to the outer periphery of each pad leg; a bight mount located ex teriorly of the pad bight; flexible back-up means extending about the outer periphery of the pad; means connecting each end of the back-up means to a leg mount; means receiving the mid-portion of the back-up means in the bight mount; a beam located rearwardly of the bight mount that receives the bight mount; a lever leg located outwardly of each pad leg; means mounting each lever leg on the beam for swinging movement about an axis that is transverse to said prescribed plane; means for initially maintaining the lever legs and the pad legs in an outer position; a link extending forwardly and inwardly from each lever leg to its associated leg mount; means pivotally connecting the rears of the links to the lever legs about axes that are parallel to the first mentioned axis; means pivotally connecting the fronts of the links to the leg mounts about axes that are parallel to the first mentioned axis; a bar secured to each lever leg outwardly of its associated link so that each bar is spaced from its associated link when the lever legs and pad legs are in said outer position; and drive means operative to swing the lever legs about their axes; whereby the pivotal connections between the links, the lever legs and the leg mounts causes each of the pad legs to move in a direction having a component of movement extending from the heel to the toe of the shoe assembly until the bars engage the links after which each of the pad legs moves inwardly in a direction that is substantially at right angles to the longitudinal center line of the shoe assembly.

5. The heel clamping mechanism, as defined in claim 4, further comprising: a tang connected to each of the leg mounts and underlying its associated pad leg; and a tang connected to the bight mount and underlying the pad bight.

References Cited UNITED STATES PATENTS 1,039,519 6/1912 Macleod 1214.4 3,115,649 12/1963 Kamborian et a1 1214.4 3,138,810 6/1964 Becker 1214.4 X

PATRICK D. LAWSON, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 325, 841 June 20, 1967 Horst M. Leonhardt It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

' Colur m 7, line 68 and column 8, lines 10 and 11, after 'stationary", each occurrence, insert a semicolon.

Signed and sealed this 26th day of December 1967.

(SEAL) Attest:

EDWARD J. BRENNER Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer

Claims (1)

1. A METHOD OF CLAMPING THE HEEL PORTION OF A SHOE ASSEMBLY, WHEREIN SAID ASSEMBLY INCLUDES A LAST HAVING AN UPPER MOUNTED THEREON, COMPRISING: MAINTAINING THE SHOE ASSEMBLY STATIONARY PROVIDING A CLAMPING PAD HAVING A BIGHT AND A PAIR OF LEGS EXTENDING FORWARDLY OF THE BIGHT ON OPPOSITE SIDES OF THE BIGHT; LOCATING THE PAD IN A STATIONARY POSITION WITH THE BIGHT IN ENGAGEMENT WITH THE HEEL END OF THE SHOE ASSEMBLY AND THE LEGS EXTENDING OUTWARDLY OF THE HEEL OF THE SHOE ASSEMBLY ON OPPOSITE SIDES THEREOF; AND THEREAFTER CAUSING THE LEGS TO MOVE INWARDLY TO BEAR AGAINST THE HEEL PORTION OF THE SHOE ASSEMBLY BY SO MOVING THE LEGS THAT INITIALLY EACH LEG MOVES IN A DIRECTION HAVING A COMPONENT OF MOVEMENT EXTENDING FROM THE HEEL TO THE TOE OF THE SHOE ASSEMBLY AND THEN EACH LEG MOVES IN A DIRECTION THAT IS SUBSTANTIALLY AT RIGHT ANGLES TO THE LONGITUDINAL CENTER LINE OF THE SHOE ASSEMBLY.

Images