GB1323415A - Workpiece holding devices - Google Patents

Abstract

1323415 Boots &c BRITISH UNITED SHOE MACHINERY CO Ltd 6 July 1970 [4 July 1969] 33810/69 Heading A3B [Also in Divisions B3 B8 and F2] A workpiece holding device comprises a valve arrangement 32 having a body member 40, Fig. 3, formed with a cavity 42 opening into a workpiece engaging surface 34, a passageway 56 having a mouth portion opening into a wall of the cavity whereby the cavity can be connected to a vacuum source, and a closure member 50 loosely retained in the cavity and capable of being drawn, by fluid flow from the cavity into the passageway, into the mouth portion to close the passage way and, when in that position, to have a portion projecting beyond the workpiece engaging surface, movement from the projecting position unseating the closure member from the mouth portion to re-establish the connection between the cavity and the passageway. A number of valve arrangements may be mounted in the workpiece engaging surface, each consisting of a cylindrical plastics body member formed with a lip 62 for retaining the closure member, which may comprise a light single-ball 50, in its cavity 42. A flattened portion forms a passage 58 communicating with the passageway 56, the mouth 60 of which is part spherical so that the bill seals the passageway when a vacuum is applied to the passage 58. When a workpiece is placed on the surface 34, the ball is dislodged and vacuum applied to the cavity to hold the workpiece on the surface 34. In another embodiment, the mouth of the passageway is provided with a seal 158, Fig. 4, and a valve 190 can be operated to connect the cavity 142 to exhaust 200. In a further embodiment, the body of the valve is surrounded by a seal (279, Fig. 7, not shown) having a flexible lip (280) for engagement with a workpiece, such as a shoe sole, having an uneven surface. The workpiece holding device may be used in apparatus for assembling and bonding together components of a shoe upper, the apparatus having a cabinet 10, Fig. 1, formed with first and second workpiece supports 12, 16 mounted on an inclined upper surface 18 of the cabinet. Each support consists of a base-shaped structure having an upper surface 30 of clear plastics material in which in a plurality of the valve arrangements 32. A projector 106 and reflector 108 project an image onto the surface 30 of the support 12 to enable an operator to accurately position a workpiece u on the surface where it is held by the valve arrangements 32. A transfer device consisting of a platen 72 having a lower surface 74, in which are a plurality of the valve arrangements 32, is mounted in an arm 70 movable about a pivot 71 by a gear 80 engaged by a rack 84 movable by a piston-andcylinder device 88. The platen can be raised and lowered on the arm by a piston-andcylinder device 103. A heating station 110 is positioned on the surface 18 of the cabinet. When the operator has positioned a component U of the workpiece on the first support 12, the transfer device is swung about its pivot to a position over the support 12 and the device 103 actuated to lower the platen and actuate a valve 95 to cause a vacuum to be connected to the platen and disconnected from the support 12 so that the component is held by the platen which is then raised. The transfer device is then moved above the second support 16 and the platen lowered for the component to be held by the support 16. A second component of the workpiece is positioned on the first support 12 and the procedure repeated to position the second component on the first. If the components are to be bonded together, the transfer device dwealls above the heating station to heat the adhesive on the component.