Title of Invention

A LAST FOR MANUFACTURING SLIP-LASTED FOOT WEAR AND A SLIPPING-ON LASTING MACHINE

Abstract

A last for manufacturing slip-lasted footwear comprises : (a) a fore part (3) and a heel part (5) movable relative to each other between an open position and a closed position ; (b) a means for biasing the two parts in the closed position; and (c) a locking device for locking the two parts in the closed position, and comprising (i) a pair of locking members (45), one on each side of the last,that are movable between a locked position in which the locking members prevent relative movement of the fore and heel parts from the closed position and an unlocked position in which the locking members do not prevent such relative movement, and (ii) a means (61) for biasing the locking members into the locked position.

Full Text

- 1A - The present invention relates to a last for manufacturing slip-lasted footwear and a slipping-on lasting machine. The two-piece last that is typically used for manufacturing slip-lasted footwear has separately formed fore and heel parts that have complementary curved contact surfaces on a rear end of the fore part and a forward end of the heel part. The fore and heel parts are connected together by a spring mechanism and can move relative to each other along the curved path defined by the contact surfaces. The spring mechanism biases the fore and heel parts towards a closed position in which the fore and heel parts define a footwear shape. The fore and heel parts can be moved relative to each other along the curved path away from the closed position to an open position that effectively reduces the length of the last. This relative movement of the fore and heel parts between closed and open positions is referred to as "breaking" the last. The "breaking" action allows an upper/insole assembly to be positioned initially on a last in a first step in manufacturing slip-lasted footwear. The "breaking" action also allows manufactured footwear to be removed from a last. - 2 - Slip-lasted footwear uses special precision manufactured lasts that are made to accurate tolerances. Special precision manufactured lasts are required because slip-lasted footwear remains on a last for a wider range of operations during manufacture of the footwear and dimensional accuracy of the last is required to facilitate robotic processes and accurate moulding of a sole onto the bottom of slip-lasted footwear. The slip-lasting operation includes a series of steps that are carried out on a slipping-on lasting machine. The following description is in the context of safety footwear that includes a steel toecap. The series of steps includes a first step of positioning an upper/insole assembly on a last while the last is in the open, ie "broken", position. The toe part of the upper is folded back. The last is then closed, and the movement of the last from the open to the closed positions places the upper/insole assembly under considerable tension. The tension within the upper/insole assembly exerts forces that are complex and multi-directional. A toecap is then positioned on the toe while the last is in the closed position. The last is then transferred to a toe lasting machine on which the toe part of the upper is folded over the toecap. The toe lasting machine then applies considerable forward and rearward pressures to the last to properly shape the upper/insole assembly. The last is then transferred to a moulding machine and a series of operations are carried out on the upper/insole assembly while the assembly is on the last. The operations include robotically roughing the edge of the upper to permit cell bonding and thereafter moulding a sole onto the upper/insole assembly. - 3 - Finally, the moulded footwear is removed from the moulding machine and while still on the last is transferred to a last removal station at which the footwear is removed from the last. This step involves braking the last. The considerable forces that act on an upper/insole assembly at a slipping-on lasting machine can partially "break" the last on the machine. In addition, the considerable forward and rearward pressures that are applied to a last at a toe lasting machine can also partially "break" the last. Such partial "breaking" of a last on slipping-on and/or toe lasting machines results in misalignment of the fore and heel parts of the last. The misalignment produces imperfectly lasted footwear. More specifically, the "breaking" of a last through even a few degrees shortens the length of the last during critical moments when an upper is formed to its shape on- the slipping-on and toe lasting machines. The adverse effects of such imperfectly lasted footwear include: • Incorrect placement of robotic roughing line on the upper. • Incorrect mould bite-line in relation to an upper. • Incorrect alignment of mould bite-line with roughing line, leading to one or more of: exposed roughing on the upper, sole "gaping" at junction with upper, poor seal of moulds on an upper with consequential "leakage" of injected mould material and resulting upper damage, and poor adhesion or incomplete filling of the sole moulds - 4 – due to loss of in-mould pressure. • Distorted footwear, resulting in poor fit. Consequently, it is common practice to strike a heel part of a last with a hammer to close a partially "broken" last on slipping-on and toe lasting machines. Often, considerable force has to be applied by the hammer blows to close partially "broken" lasts. This action interrupts the normal manufacturing sequence at these machines and can cause significant damage to footwear and lasts. In addition to the above, a last must be "closed" in order for the operations of robotically roughing the edge of an upper and moulding a sole onto an upper/insole assembly to be carried out on a moulding machine. Often this can only be achieved by hammer blows (often with considerable force) to a heel part of a last. As is noted above, closing a last with hammer blows interrupts the normal manufacturing sequence and can cause significant damage to footwear and lasts. An object of the present invention is to provide a last locking device that prevents uncontrolled "breaking" of lasts. According to the present invention there is provided a last for manufacturing slip-lasted footwear,said last comprising : (a) a fore part and a heel part which are connected together so that the fore part and the heel part can move relative to each other between an open position in which an upper/insole assembly can be fitted on the last and a closed position in which the fore part and the heel part define a required footwear shape and the upper/ insole assembly is tensioned on the last; - 5 – (b) a means for biasing the fore part and the heel part in the closed position;and (c) a locking device for locking the fore part and the heel part in the closed position, the locking device comprising(i) a pair of locking members,one on each side of the last, that are movable between a locked position in which the locking members prevent relative movement of the fore part and the heel part from the closed position and an unlocked position in which the locking members do not prevent such relative movement and (ii)a means for biasing the locking members into the locked position. Preferably the locking members are mounted to the fore part for movement between the locked and unlocked positions in response to engagement of the last in a slipping-on lasting machine. Preferably the locking members are mounted to the fore part for movement between the unlocked and locked positions in response to disengagement of the last from the slipping-on lasting machine. An important feature of the present invention is that the locking device is adapted to be used with conventional machinery for manufacturing slip-lasted footwear. In particular, the locking device is adapted to be used with conventional moulding machines. - 6 - Preferably the heel part includes a body that defines part of a footwear shape and a mounting plate for mounting the heel part to slip-lasted footwear manufacturing machinery. The term "slip-lasted footwear manufacturing machinery" is understood herein to mean any one or more of slipping-on lasting machines, toe-lasting machines, and moulding machines. Preferably there are gaps between the body and the mounting plate for receiving the locking members. With this arrangement, when the last is in the closed position, preferably the locking members are in the locked position when the locking members extend across a join line between the fore part and the heel part and into the gaps between the heel body and the mounting plate, whereby movement of the heel part relative to the fore part from the closed position towards the open position immediately brings the mounting plate into contact with the locking members. The result is that the locking members prevent further movement of the fore part and the heel part from the closed position and thereby lock the last in the closed position. Preferably each locking member is pivotally mounted to the fore part and can swing towards and away from the last about a pivot connection between the locking member and the fore part and thereby move between the unlocked and the locked positions. Preferably each locking member includes an outwardly facing locking lug arranged to be engaged by locking jaws on the slipping-on lasting machine, whereby in use contact of the locking jaws causes the locking - 7 – members to swing from the locked to the unlocked positions. Preferably the locking members are pivotally mounted to the fore part so that contact of the locking jaws causes the locking members to swing outwardly from the locked to the unlocked positions. Preferably the biasing means for the locking members includes a compression spring connected at opposite ends to the locking members. Preferably the fore part includes a body that defines the other part of the footwear shape and a mounting plate for mounting the fore part to slip-lasted footwear manufacturing machinery. Preferably one of the mounting plates of the fore part and the heel part includes an alignment pin and the other of the mounting plates of the fore part and the heel part includes a recess for receiving the alignment pin to ensure alignment of the fore part and the heel part when the last is in the closed position. According to the present invention there is also provided a slipping-on lasting machine comprising : (a) a pedestal for supporting a last, the last comprising a fore part and a heel part which are connected together so that the fore part and the heel part can move relative to each other between an open position in which an upper/insole assembly can be fitted on the last and a closed position in which the fore part and the heel part define a required footwear shape and the upper/insole assembly is tensioned on the last, the last also comprising a locking device for locking the fore part and the heel part in the closed position, the locking device comprising a pair of locking members, one on each - 8 – side of the last, and a means for biasing the locking members into a locked position ; (b) a pair of spaced-apart locking jaws mounted to the pedestal for engaging the last to hold the last securely in position on the slipping-on lasting machine, the last and the locking jaws being formed whereby engagement of the locking jaws with the last moves the last locking members to an unlocked position whereby the heel part can be moved relative to the fore part from the closed position to the open position; and (c) a means for moving the heel part relative to the fore part between the closed position and the open position. The present invention is described further by way of example with reference to the accompanying drawings, in which: Figure 1 is a side view of a preferred embodiment of a last in accordance with the present invention in a closed positions; Figure 2 is a side view of the last in an open "broken" position; Figure 3 is a side view of mounting plate assembly of the last in the closed position which illustrates the locking members in a locked position; - 9 - Figure 4 is a plan view of the mounting plate assembly when viewed in the direction of the arrow X in Figure 3; Figure 5 is a cross-section along the line 5-5 in Figure 4; Figure 6 is a plan view similar to that shown in Figure 4 but with the locking members in an open position; Figure 7 is a side view of a part of an upper section of a slipping-on lasting machine which illustrates the position of the last shown in Figures 1 to 6 in a closed position on the machine; Figure 8 is a plan view in the direction of the arrow Y in Figure 7 with the body parts of the lasts removed for clarity which illustrates the action of locking jaws of the slipping-on lasting machine to bias the locking members of the last into an unlocked position; and Figure 9 is a partially exploded perspective view of the arrangement shown in Figure 7 but with greater detail than is evident from Figure 7 and with the last in the open "broken" position. The two-part footwear last shown in Figures 1 and 2 includes a fore part, generally identified by the numeral 3, and a heel part, generally identified by the numeral 5. The fore part 3 includes a body 7 that defines a part of a footwear shape and a mounting plate 9 for mounting the fore part 3 to slip-lasted footwear manufacturing machinery. - 10 - Similarly, the heel part 5 includes a body 11 that defines the other part of a footwear shape and a mounting plate 13 for mounting the heel part 5 to slip-lasted footwear manufacturing machinery. The fore part 3 and the heel part 5 have complementary curved contact surfaces 15, 17 on a rear end of the fore part 3 and a forward end of the heel part 5. The fore and heel parts 3,5 are connected together by a spring mechanism (not shown) and can move relative to each other along the curved path defined by the contact surfaces 15,17. The spring mechanism biases the fore and heel parts towards the closed position shown in Figure 1 in which the fore and heel parts define a footwear shape. The fore and heel parts 3,5 can be moved relative to each other along the curved path away from the closed position shown in Figure 1 to an open position shown in Figures 2 and 9. The mounting plate 9 has a top opening 25 and side channels 31 and the mounting plate 13 has side channels 31 that facilitate mounting the fore and heel parts 3,5 to slip-lasted footwear manufacturing machinery. This is illustrated in part in Figures 7 and 9. The figures show the last positioned on a pedestal 91 of a slipping-on lasting machine, with a last locating pin 33 of the machine extending into the opening 25 and into an aligned opening 41 in the body 7 of the fore part 3 and a pair of pivoting locking jaws 37 of the machine extending into the channels 31 and and holding the fore part 3 on the machine. With this arrangement, the fore part 3 is held firmly in a fixed position on the pedestal 91 and, as can be seen in Figure 9, the heel part 5 can be moved relative to the fore part 3. - 11 - The two-part footwear last shown in the figures is a conventional construction save that it includes a locking device for locking the fore part 3 and the heel part 5 in the closed position shown in Figure 1. The locking device includes a pair of locking members 45, one on each side of the last, that are pivotally mounted via pivot pins 51 to the fore part mounting plate 9. The locking members 45 can swing between a locked position shown in Figures 1, 3, 4, 5, and 9 and an unlocked position shown in Figures 2, 6, 7, and 8. The locking device also includes a compression spring 61 that biases the locking members 45 into the locked position. In the locked position shown in Figures 1, 3, 4, 5, and 9 the arms 53 of the locking members 45 extend across a join 57 between the mounting plates 9,13 and into a gap 81 between the heel part mounting plate 13 and the heel part body 5. In this position the arms 53 prevent relative movement of the fore and heel parts 3,5 from the closed position shown in Figure 1 to the open position shown in Figure 2. Specifically, any attempt to move the heel part 5 relative to the fore part 3 from the closed position to the open position brings the extension 83 of the heel mounting plate 13 into contact with the arms 53 and the arms 53 prevent further movement. The compression spring 61 biases the locking members 45 into the locked position. The locking members 45 are formed to move from the locked position to the unlocked position during the process of initially positioning a closed last on - 12 - slipping-on lasting machine. The slipping-on lasting machine can then be operated in accordance with standard operating procedures without interference from the locking device. In addition, the locking members 45 are formed to move from the unlocked position to the locked position during the process of releasing a closed last from a slipping-on lasting machine. The locked closed last can then be transferred to other slip-lasted footwear manufacturing machinery and further footwear manufacturing operations can be carried out on the lasted footwear. Specifically, with reference to the slipping-on lasting machine shown - - Figures 7 and 9, the locking members 45 include lugs 65 that are engaged and forced inwardly by appropriately positioned blocks 61 on the fore part locking jaws 37 of the slipping-on lasting machine. The result of the inward, ie pivoting, movement of the lugs 65 is that the arms 53 of the locking members 45 swing, ie pivot, outwardly clear of the heel part mounting plate 13 and thus the fore part 3 and the heel part 5 are no longer locked together by the arms 53. In particular, the heel part 5 can be moved relative to the fore part 3 from the closed position shown in Figure 1 to "break" the last so that an upper/insole assembly can be positioned on the last and the heel part 5 can then be moved back to the closed position shown in Figure 1 so that subsequent standard lasting steps can be carried out on the machine. In addition, when the lasting steps on the machine have been completed and the last is in the closed position shown in Figure 1, the process of disengaging the locking jaws 37 from the last allows the lugs 65 to be pushed outwardly in response to the force applied by the - 13 - compression spring 61, and this movement results in the arms 53 swinging inwardly into the locked position shown in Figures 1, 3, 4, 5, and 9. Many modifications may be made to the preferred embodiment of" the present invention as described above in relation to the drawings without departing from the spirit and scope of the invention. - 14 - WE CLAIM: 1. A last for manufacturing slip-lasted footwear, said last comprising : (a) a fore part (3) and a heel part (5) which are connected together so that the fore part and the heel part can move relative to each other between an open position in which an upper/insole assembly can be fitted on the last and a closed position in which the fore part and the heel part define a required footwear shape and the upper/insole assembly is tensioned on the last; (b) a means for biasing the fore part and the heel part in the closed position; and (c) a locking device for locking the fore part and the heel part in the closed position, the locking device comprising (i) a pair of locking members (45), one on each side of the last,that are movable between a locked position in which the locking members prevent relative movement of the fore part and the heel part from the closed position and an unlocked position in which the locking members do not prevent such relative movement and (ii) a means (61) for biasing the locking members into the locked position. - 15 - 2. The last as claimed in claim 1, wherein the locking members (45) are mounted to the fore part (3) for movement between the locked and unlocked positions in response to engagement of the last in a slipping-on lasting machine. 3. The last as claimed in claim 2, wherein the locking members (45) are mounted to the fore part for movement between the unlocked and locked positions in response to disengagement of the last from the slipping-on lasting machine. 4. The last as claimed in any one of the preceding claims wherein the heel part (5) comprises a body (11) that defines part of a footwear shape and a mounting plate (13) for mounting the heel part to slip-lasted footwear manufacturing machinery. 5. The last as claimed in any one of the preceding claims wherein the fore part (3) comprises a body (7) that defines the other part . of the footwear shape and a mounting plate (9) for mounting the fore part to slip-lasted footwear manufacturing machinery. - 16 - 6. The last as claimed in claim 5, wherein one of the mounting plates of the fore part (3) and the heel part (5) is provided with an alignment pin and the other of the mounting plates of the fore part and the heel part has a recess for receiving the alignment pin to ensure alignment of the fore part and the heel part when the last is in the closed position. 7. The last as claimed in any one of claims 4 to 6, wherein gaps (81) are provided between the body (7,11) and the mounting plate (9,13) for receiving the locking members (45), whereby when the last is in the closed position the locking members are in the locked position when the locking members extend across a join line (57) between the fore part and the heel part and into the gaps between the heel body (11) and the mounting plate, whereby movement of the heel part relative to the fore part from the closed position towards the open position brings the mounting plate into contact with the locking members and the locking members thereby prevent further movement of the fore part and the heel part from the closed position and lock the last in the closed position. - 17 - 8. The last as claimed in any one of the preceding claims wherein each locking member is pivotally mounted to the fore part (3) and can swing towards and away from the last about a pivot connection (51) between the locking member and the fore part and thereby move between the unlocked position and the locked position. 9. The last as claimed in claim 8, wherein each locking member comprises an outwardly facing locking lug (65) arranged to be engaged by locking jaws (37) on a slipping-on lasting machine, whereby in use contact of the locking jaws causes the locking members to swing from the locked position to the unlocked position. 10. The last as claimed in claim 8, wherein the locking members are pivotally mounted to the fore part so that contact of the locking jaws (37) with the locking lugs (65) causes the locking members to swing outwardly from the locked position to the unlocked position. 11. The last as claimed in any one of the preceding claims wherein the biasing means for the locking members comprises a compression spring (61) connected at opposite ends to the locking members. - 18 – 12. A slipping-on lasting machine comprising : (a) a pedestal (91) for supporting a last, the last comprising a fore part (3) and a heel part {5} which are connected together so that the fore part and the heel part can move relative to each other between an open position in which an upper/insole assembly can be fitted on the last and a closed position in which the fore part and the heel part define a required footwear shape and the upper/insole assembly is tensioned on the last, the last also comprising a locking device for locking the fore part and the heel part in the closed position/ the locking device comprising a pair of locking members (45), one on each side of the last, and a means (61) for biasing the locking members into a locked position; (b) a pair of spaced-apart locking jaws (37) mounted to the pedestal for engaging the last to hold the last securely in position on the slipping-on lasting machine,the last and the locking jaws being formed whereby engagement of the locking jaws with the last moves the last locking members to an unlocked position whereby the heel part can be moved relative to the fore part from the closed position to the open position; and (c) a means for moving the heel part relative to the fore part between the closed position and the open position. - 19 - 13. A last for manufacturing slip-lasted footwear, substantially as herein described, particularly with reference to the accompanying drawings. 14. A slipping-on lasting machine, substantially as herein described, particularly with reference to the accompanying drawings. A last for manufacturing slip-lasted footwear comprises : (a) a fore part (3) and a heel part (5) movable relative to each other between an open position and a closed position ; (b) a means for biasing the two parts in the closed position; and (c) a locking device for locking the two parts in the closed position, and comprising (i) a pair of locking members (45), one on each side of the last,that are movable between a locked position in which the locking members prevent relative movement of the fore and heel parts from the closed position and an unlocked position in which the locking members do not prevent such relative movement, and (ii) a means (61) for biasing the locking members into the locked position.

Documents:

00245-kol-2003-abstract.pdf

00245-kol-2003-claims.pdf

00245-kol-2003-correspondence.pdf

00245-kol-2003-description(complete).pdf

00245-kol-2003-drawings.pdf

00245-kol-2003-form-1.pdf

00245-kol-2003-form-18.pdf

00245-kol-2003-form-2.pdf

00245-kol-2003-form-3.pdf

00245-kol-2003-form-5.pdf

00245-kol-2003-g.p.a.pdf

00245-kol-2003-letters patent.pdf

00245-kol-2003-priority document.pdf

245-kol-2003-granted-abstract.pdf

245-kol-2003-granted-claims.pdf

245-kol-2003-granted-description (complete).pdf

245-kol-2003-granted-drawings.pdf

245-kol-2003-granted-form 2.pdf

245-kol-2003-granted-specification.pdf

245-kol-2003-priority document.pdf