Shoe last holding device and shoemaking machine having the same

Abstract

A shoe last holding device for clamping a shoe last including two spaced-apart clamped portions includes a base seat unit, a driving unit, and a clamping unit. The driving unit includes a pushing member movable relative to the base seat unit. The clamping unit includes two spaced-apart clamping elements pivotally mounted to the base seat unit. Each clamping element includes a force transmission end abutting against the pushing member and a clamping end opposite to the force transmission end. The pushing member is disposed between and movable toward and away from the clamping elements to drive the clamping elements to convert between a releasing state and a clamping state where the clamping ends engage the clamped portions, respectively.

What is claimed is: 
     
         1 . A shoe last holding device for a shoemaking machine adapted to be mounted on a machine body unit and to clamp a shoe last, the shoe last including two spaced-apart clamped portions to be held by the shoe last holding device, said shoe last holding device comprising:
 a base seat unit mounted to the machine body unit;   a driving unit mounted to said base seat unit and including a pushing member movable relative to said base seat unit along a front-rear direction; and   a clamping unit including two clamping elements that are spaced apart from each other along a left-right direction transverse to the front-rear direction and that are pivotally mounted to said base seat unit, each of said clamping elements including a force transmission end abutting against said pushing member and a clamping end opposite to said force transmission end, said pushing member of said driving unit being disposed between and movable toward and away from said clamping elements along the front-rear direction to drive said clamping elements to convert between a releasing state, where said force transmission ends of said clamping elements are spaced apart from each other along the left-right direction by a first distance so that said clamping ends of said clamping elements are spaced apart from the clamped portions of the shoe last, and a clamping state, where said force transmission ends of said clamping elements are spaced apart from each other along the left-right direction by a second distance that is greater than the first distance so that said clamping ends of said clamping elements clamp the shoe last therebetween such that said clamping ends engage the clamped portions, respectively.   
     
     
         2 . The shoe last holding device for a shoemaking machine as claimed in  claim 1 , wherein said base seat unit includes a base wall for mounting of said driving unit, and a shaft seat extending downwardly from said base wall along an up-down direction transverse to the front-rear direction and the left-right direction, and permitting said clamping elements to pivotally connected thereto, said clamping unit further including two biasing members each of which is mounted between a respective one of said clamping elements and said shaft seat, and biases a respective one of said clamping ends away from said shaft seat. 
     
     
         3 . The shoe last holding device for a shoemaking machine as claimed in  claim 2 , wherein said shaft seat includes a fixing portion mounted to said base wall and a shaft end portion opposite to said fixing portion along the up-down direction, said shaft end portion being formed with two cavities that are spaced apart from each other and that extend along the left-right direction, said clamping elements respectively including two blind holes aligned with said cavities, respectively, each of said biasing members being disposed in a respective one of said cavities and a corresponding one of said blind holes. 
     
     
         4 . The shoe last holding device for a shoemaking machine as claimed in  claim 3 , wherein each of said clamping elements further includes a main plate having said force transmission end, said clamping end, and a respective one of said blind holes, two pivot jointing lugs extending from said main portion, and spaced apart from each other along the front-rear direction, and two pivot pins extending respectively through said pivot jointing lugs, said shaft end portion of said shaft seat being formed with two pivot holes which correspond in position respectively to said clamping elements, each of which extends along the front-rear direction, and each of which permits a respective one of said pivot pins to extend through to allow a corresponding one of said clamping elements to pivot relative to said base seat unit. 
     
     
         5 . The shoe last holding device for a shoemaking machine as claimed in  claim 3 , wherein said pushing member includes two pushing portions spaced apart from each other along the left-right direction and a notch formed between said pushing portions and provided for said shaft seat to extend therethrough, each of said pushing portions extending between the said shaft seat and a respective one of said clamping elements and abutting against a corresponding one of said force transmission ends. 
     
     
         6 . The shoe last holding device for a shoemaking machine as claimed in  claim 5 , wherein said fixing portion of said shaft seat extends through said notch, and said pushing portions being in sliding contact with said fixing portion. 
     
     
         7 . The shoe last holding device for a shoemaking machine as claimed in  claim 5 , wherein said force transmission end of each of said clamping elements has a first inclined surface facing toward said driving unit and extending rearwardly and outwardly, each of said pushing portions of said pushing member having a first pushing surface parallel to said first inclined surface, said first pushing surfaces of said pushing portions abutting respectively against said first inclined surfaces of said clamping elements when said clamping elements are in the releasing state. 
     
     
         8 . The shoe last holding device for a shoemaking machine as claimed in  claim 7 , wherein said force transmission end of each of said clamping elements further has a second inclined surface extending forwardly and inwardly from a front end of said first inclined surface, each of said pushing portions of said pushing member further having a second pushing surface that extends rearwardly and outwardly from a rear end of a respective one of said first pushing surfaces and that is parallel to said second inclined surface, said second pushing surface of said pushing portions abutting respectively against said second inclined surfaces of said clamping elements when said clamping elements are in the clamping state. 
     
     
         9 . The shoe last holding device for a shoemaking machine as claimed in  claim 8 , wherein said base wall is formed with a receiving slot open rearwardly along the front-rear direction, said driving unit including a cylinder disposed in said receiving slot and a piston rod mounted reciprocatingly to said cylinder, movable along the front-rear direction, and having one end that is mounted fixedly to said pushing member to drive said pushing member to move along the front-rear direction.