Patent GB-1281515-A (GB)
Title: Improvements in machine tools and mechanisms for handling workpieces in conjunction therewith
Inventor: PRITCHARD RALPH HARRY GEORGE
IPC: B23Q7/04
Filed: 1968-07-10
Abstract: 1281515 Work transferring PRECISION GEAR MACHINES & TOOLS Ltd 10 July 1969 [10 July 1968] 32996/68 Heading B3B Workpiece handling apparatus in a machine tool comprises a workpiece transfer device for receiving a new workpiece, e.g. a gear cluster, from a receiving station e.g. a conveyer, transferring it to a work station between centres in the machine tool, engaging a finished workpiece from a support device which has removed the finished workpiece from the work station and returning it to the conveyer where it is transported away. The transfer device comprises an arm 23 axially displaceable in a casing 24 by fluid pressure piston and cylinder means 25. The arm 23 carries a gripping jaw assembly 22 having two sets of jaws 63, 64 and 65, 66 at its operative end supported on an adaptor 92 which incorporates a piston and cylinder assembly 71, 72, which effects actuation of the jaws to grip the workpiece. The casing 24 is provided with a helical slot 29 which is engaged by a roller 27 on the arm 23 whereby axial displacement of the arm in the casing also effects its rotation, in order that a workpiece received in one orientation may be moved to another to facilitate correct alignment in the machine tool. The arm and casing are together displaceable transversely to the arm axis by a compound piston, cylinder and sleeve assembly 30 to 34 and 37, secured to the casing 24 and a plate member carrying switches which are actuated by cams and control two stage movement of the piston assembly and whereby the arm may be raised to two positions. The apparatus further includes a support device mounted on or adjacent to the machine which comprises two arms 120 mounted on a shaft 121 pivotable by fluid pressure means (not shown). The free ends of the arms have two part jaw members 131, 132 adapted to grip a finished workpiece, support it when it is released from the machining station in the machine and lowering it to a position which allows the arm of the transferring device to locate a fresh workpiece in the machining station. The apparatus is operated sequentially by the action of cam actuated switches in the following manner. The arm 23 is displaced axially to receive and engage by the jaw assembly 22 a workpiece supported on a conveyer 20; the arm is then raised and further extended to orientate the workpiece for its location in machining station. When clamped in the machine tool the workpiece is released by one set of jaws 63, 64 on the arm 23 and the arm is lowered to permit a further set of jaws 65, 66 to engage the finished workpiece in the arms of the support device. The transfer arm 23 is then retracted which removes the workpiece from the support device and reorientates it for its subsequent location on the conveyer where it is transported away. A modified form of transfer device is described in which the arm is formed by two parallel bars with connecting members at each lid, the operative end having a rotatable spigot which carries the jaw assembly and which is rotated by gear means with a cam and stops to control the extent of rotation. The fluid pressure means for raising and lowering the arm is provided with two fluid pressure cylinders axially aligned with a support plate there between.