Patent GB-491633-A (GB)
Title: Improvements in or relating to boring machines and like machine tools
IPC: B23Q1/00
Filed: 1937-11-17
Abstract: 491,633. Boring, drilling, and milling machines; lathes. ASSOCIATED EQUIPMENT CO., Ltd., JONES, E. J. H., and FRANCIS, A. A. J. Nov. 17, 1937, No. 31643. [Class 83 (iii)] In a machine tool such as a lathe, boring, drilling, or milling machine wherein a rotary spindle and a work carrier have relative movement by power means under hand control, the hand control device is mounted on a movable support which may be adjusted to one side or the other of the table according to the position of the operator. As applied to a boring machine the bed 10 has horizontal guides 11 for the work table 13 and vertical guides 17 on a pillar 15 for the boring head 18 which may carry parallel spindles 19 and 29..31. The head is adjusted vertically by a nut therein rotatable by a hand wheel 21 and engaging a fixed screw 20, a balance weight within the pillar being attached to the head by a chain 26. Hand levers 23 .. 25 control the spindle speed from a motor 22 on the head and a hand lever 27 locks the head in adjusted position. The table 13 is fed by a screw 32, Fig. 4, driven through gearing 34 from a. shaft 36 which may be rotated from either of the motors 41, 42 on the bed through a differential gear for fast traverse or slow feed respectively. Pins 40<1> on the shaft 36 carry bevel pinions 40 engaging bevel gears 47, 48 rotated respectively by the motors 41, 42, a spur gear 45 on the bevel gear 47 being driven by the pinion 44 on the shaft 43 of the motor 41, whilst the low speed motor 42 drives the bevel gear 48 through gearing 55, a change speed gear comprising sliding gears 60, 61 and 68 and a worm drive 50. When the motor 41 is driving, the non-reversible worm drive 50 prevents rotation of the bevel gear 48, but when the motor 42 is driving, rotation of the bevel gear 47 is prevented by an electrically controlled brake 72, Fig. 1, which is applied automatically when the motor is de-energized, but which may slip to allow the traverse to be relieved on overload. A similar overload device may be provided for the feed. For rapid feed rates, a skew gear may replace the worm drive 50 and a brake is then applied to the motor 42. The motor 41 is reversible for rapid traverse in either direction and a reversing gear 88 may be employed for reversing the direction of the cutting feed. The sliding gears 60, 61 and 68 are controlled by yokes 62, 63 and 69 operated by racks 64, 65, 70 and pinions 66, 67 and 71. The latter are rotated by further racks attached to rods 92, 93, 94 connected to hand levers 89, 90, 91 by links 95 and levers 98. The levers 90, 91 are interconnected by toothed quadrants 103 to ensure correct action. The electric motors are controlled by push button switches 73, 74 the former being for the spindle motor 22 and the latter for the traverse and feed motors 41, 42. The switches are carried by a tubular arm 75 containing the leads, which is attached to a collar 76 rotatably mounted on a hollow stud secured to the pillar 15 and held in position by a cover plate 78. A notch in the cover provides shoulders to co-operate with a web 79 on the arm to limit its horizontal movement so that it may be swung to position the switches at whichever side of the table 13 and the work the operator desires. The boring bars carried by the spindles 19 &c. extend into bearings on the table 13, and limit switches may be provided to co-operate with the table and limit its travel.