| 摘要 |
1,171,041. Grinding. CARBORUNDUM CO. 25 April, 1968 [28 April, 1967], No. 19594/68. Heading B3D. Apparatus for pressing a workpiece against a machine tool, such as a grinding wheel 16, comprises a work rest 54, a member 56, 58 pivotally mounted on the work rest, a slide 62 slidable along the member, the member having a work-supporting portion 56, an abutment 104 having a work-engaging surface mounted on a horizontal axis 71 on the slide, and means 106 carried by the slide for urging the workengaging surface against a workpiece. The grinding wheel is belt-driven from a motor and mounted in a casing having a door. The work rest 54 is secured to a bar 48 vertically adjustable on the casing and provided with a pivotal connection 57 to a T-shaped member 56, 58. The slide 62 is clampable in adjusted position along a slot 60 in the member, a pin 70 and bolt 72 sliding in the slot and a handle 86 acting on bolt 72 to clamp the slide. The slide comprises two plates joined at their lower ends by a pin 71 on which a pair of cranked arms 92 are mounted, the arms being joined at their upper ends by the work-engaging abutment 104. The arms are rocked about the pin to cause the abutment 104 to press a workpiece against the grinding wheel by a pneumatic cylinder 106, the rod of which actuates bellcrank levers 115 mounted on pin 70 and connected to a plate 122 on the abutment 104. Fluid pressure to cylinder 106 is controlled by a pressure regulating valve actuated by a lever 126 and has a pad 128 engageable by the leg of the operator of the machine. A quick exhaust valve 150 permits rapid return of the abutment 104. Fluid at reduced pressure is supplied to the rod end of cylinder 106 to bias the surface 104 to a retracted position. The member 56, 58 is clamped to the work rest 54 by a cam device 200 operated by a lever 218. On release of the cam device, the apparatus can be moved about pivot 57 to an inoperative position and the rest 54 is used for supporting a workpiece. |
