| 摘要 |
1,255,295. Brakes INTERNATIONAL STANDARD ELECTRIC CORP. 28 May, 1970 [31 May, 1969], No. 25797/70. Heading F2E. [Also in Division H1] A rotary knob 10 for mounting on a control shaft 60 of an apparatus particularly of a rotary switch has a bore receiving a click-stop fixing the position of rotation of the shaft, a socket 100 of the click-stop joined to the knob being provided with a bore 101 for passage of the shaft and being mounted to the apparatus, the socket having a contour 106 in which ball members 130, 140 guided by a ring 150 coupled to the shaft and biased by a compression spring 26 and retaining disc 160, are permitted to slide. Upon actuating the control shaft 60 balls 130, 140 engaging circular recesses in the guide ring 150 in a step by step manner to fix the position of rotation of the shaft. A collet 70 fixes the shaft to an internal sleeve 20 of the knob 10 to limit axial movement. Knob 10 also has an outer housing in three parts 30, 40, 50, on the bottom part 30 of which is moulded an indicator 32 to indicate the position of the knob. For adjusting the position of the indicator a circular cam 21 is provided along its circumference with slots 22, Fig. 2 (not shown) arranged in an angular division corresponding to the engaging positions of the knob 10, which engage a nose portion (33) of the part 30. The rotary motion of the control shaft 60 is restricted by means of limit stop rings 180, 190 having projections (181), (191) engaging recesses 25 on the housing 20 and arresting catches (182), (192) co-operating with a stop element 104, the angle between the catches being determined by the number of switching positions. |
