GB880186A - Improvements relating to work-feeding means in machine tools - Google Patents

Abstract

880,186. Drilling. RYE ENGINEERING WORKS (HIGH WYCOMBE) Ltd., EVANS, E. F., EVANS, J., and EVANS, W. C., [Representatives of EVANS, F. H.]. Oct. 15, 1958 [July 18, 1957], No. 22828/57. Class 83 (3). [Also in Group XXIII] A machine for performing operations such as sawing, drilling, slotting or tenoning on furniture parts or other workpieces comprises a chain conveyer 31 having dogs 32 which move the workpieces to a position close to withdrawable stops 43 at one or more operating stations and pusher means 48 which complete the movement of the workpiece up to the stop at the or each station. A pair of sub-assemblies 12, 13 are adjustable toward and away from each other to suit the length of workpiece and each sub-assembly carries one of the conveyer chains between rails 33, a circular saw 16 and a multiple spindle drilling head 18. Universal pivoting adjustments are provided for the saw and drilling head and the latter is also adjustable vertically. A pneumatic cylinder feeds the saw downwards and another cylinder feeds the drills horizontally. The stops 43 and the pushers 48 are carried on the inner rails 33 and are each raised against a spring by a pneumatic cylinder 45 or 50 coupled to a common supply line having a valve 52 which ensures that the stops are raised before the pushers operate. A motor 58 drives, through a reduction gear, a cam 59 controlling the sequence of operation of the machine and a crank-pin 61 connected to a pawl 65 which normally imparts intermittent rotation to a ratchet wheel 66 on a driving shaft 39 but can be withdrawn to stop the feed by a pneumatic cylinder 67 controlled by a stop-start lever. Each time a workpiece is moved into position near a stop, a lift 85 on the cam 59 trips an air valve 70 and the stops and pushers are operated. An adjustable trip 72 on the cam then operates a valve 74 and causes the saws to be lowered and the drills fed in. As the drills are fed in, a valve is operated to lower clamps on to the workpieces and when the operations on the workpieces are completed an adjustable trip 73 operates a valve 80 which causes the saws and drills to return to initial position. When the drills are nearly fully retracted, the clamp valve is again operated to release the clamps and the fall 86 of the cam 59 then operates the valve 70 to allow the stops and pushers to be retracted by their springs. An air-pressure cut-out switch may be provided to cut-out the supply to the electric motors if the air pressure falls and an additional valve may be provided to control semi-permanent disengagement of the pawl 65 by the cylinder 67. Mechanical, solenoid or hydraulic operation may be used in place of some or all of the pneumatic cylinders. The Provisional Specification refers to the tenoning head described in Specification 712,446.