GB772619A - Improvements in and relating to spring driven motors for gramophones and the like - Google Patents

Abstract

772,619. Speed governors. GARRARD ENGINEERING & MANUFACTURING CO., Ltd., and BUTLER, W. July 6, 1955 [July 27, 1954], No. 21866/54. Class 57. Abutment means, such as a pad 15, cooperating with an axially-displaceable governorcontrolled disc 13 in a spring-driven gramophone motor is mounted on a lever 17 having a surface 21 for engagement by. any one of a number of manually-controlled speed selector means 23 of differing lengths whereby the abutment means may be moved to one of a number of predetermined positions in accordance with the speed required. The governor is driven from the spring case 1 of the motor through gearing 2, 3 and worm gearing 6 and comprises a number of weights 9 each connected by a resilient arm 10 to a fixed collar 11 and to a slidable collar 12 carrying the disc 13. The lever 17 is pivoted at 18 and urged by a spring 29 into engagement with one of three pins 23 adjustably screw threaded into an arm 24 which may be rotated about the axis of a shaft 25 by a lever 26, the latter co-operating with a speed selection scale (not shown). In order to provide a slight speed adjustment at each setting, the lever 17 has an inclined contact surface 21, Fig. 4, so that as the selected pin 23 is moved across the surface 21 a very small pivotal displacement of the lever 17 is effected. Sloping ramps 41 facilitate engagement of each pin 23 with the lever 17. To prevent play and backlash in the mechanism the shaft 25 is loaded by a spring 39 and the lever 17 has a pivot bush 31, Fig. 5, into the ends of which steel balls 32 are pressed, one ball engaging in a bore 33 and the other in an aperture 34 in a spring bearing plate 35. A leaf spring 37, Fig. 2, prevents the pins 23 from unscrewing when once adjusted. The three pins 23 may be adjusted to provide speeds of 33<SP>1</SP>/ 3 , 45 and 78 revolutions per minute.