Patent GB-812598-A (GB)
Title: Improvements in and relating to an arrangement for adjusting accurately and automatically the position of a slidable member such as a stop in a drilling or like machine
IPC: B23Q5/50
Filed: 1957-03-27
Abstract: 812,598. Gauging-devices. SOC. GENEVOISE D'INSTRUMENTS DE PHYSIQUE. March 27, 1957 [May 5, 1956], No. 9972/57. Class 83 (3). Means for positioning a sliding member automatically, e.g. a stop 2 slidable in a groove 1 in the slide of a drilling-machine, comprises hammers 20, 21 at the front and rear respectively of the stop, and means controlling the hammers automatically so that they hammer the stop into the required position. A feeler 5, operated by the stop to disengage the slide-traversing mechanism when the slide reaches a predetermined position, is also arranged to control the hammers during the preceding operation, of setting the stop with the slide in the desired position. The feeler, mounted on a pivot in a casing 7 secured to the machine frame 8 and on which the hammers are also mounted, controls the pneumatically, hydraulically or, as illustrated, solenoid-operated hammers through auxiliary circuits 42, 43, Fig. 4, including circuitbreakers 11a, 11b, operated by the end 5b of the feeler, which is turned about its pivot 6 by a spring 10 to engage an abutment 9. The hammers are mounted on pivots 18, 19 in a frame 15 fixed to a shaft 12 which can be turned in its bearings 13, 14, by a hand wheel 16, to swing the hammers from an inoperative, vertical position to the operative, horizontal position illustrated, and are pressed by springs 24, 25 against an armature 28 common to two solenoids 26, 27, energized selectively by a pulsating current in order to vibrate the hammers. A spring-pressed pin 17 in the bearing 14 engages pockets in the shaft 12 in the vertical and horizontal settings of the frame 15, and a cap 35 at the end of the shaft houses a switch 41 in the auxiliary circuits and a switch 34 in the main pulsating-current circuit 33. Indicating lamps 36, 37 are provided. Operation.-With the slide in correct position, the stop 2 is moved into engagement with the feeler. The frame 15 is then pivoted to position the hammers to each end of the stop and close the switches 34, 41. With the feeler in the position illustrated, contact 11a is open and 11b closed, thus energizing auxiliary circuit 43 from a source of current 40, and operating a solenoidoperated contact-breaker 39. This interrupts the main circuit to the solenoid 27, a solenoidoperated contact-breaker 38 in the circuit 42 remaining closed to allow the main current to flow to the lamp 36 and the solenoid 26, causing the hammer 20 to strike the stop. If the stop is moved beyond the desired position, contact 11a closes and 11b is opened by the feeler, thus causing hammer 21 to strike the blows. Tightening locking screw 3 on the stop damps oscillations of the stop about the desired setting, in which the feeler is in a central position and both contacts 11a, 11b are closed, thus interrupting the main circuits to both hammer solenoids 26, 27. In a modification, Fig. 5, the hammers 20, 21 are driven rectilinearly by the solenoids 26, 27, which have separate armatures pressed by springs 24 against the hammers, the latter being fixed to a common shaft which may be turned by a handle 16 on the hammer 21 to move the hammers into the vertical position. A cam 45 on the hammer 20 operates the switches 34, 41 when the hammers are brought into the operative position.