| 摘要 |
693,957. Interrupters; control of motors. REDMOND CO., Inc. Dec. 6, 1951. [Dec. 6, 1950], No 28616/51. Classes 38 (iii) and (v) [Also in Group XXIII] Relates to a switch controlling an electric motor driving a windscreen wiper system which ensures that the wipers will be stopped in a parked position (see Group XXIII). The switch Fig. 6, includes a thin metal disc 76 supported in a housing 22 for a worm wheel 23 operating the wipers and driven from the motor by a worm having teeth 31. Secured and earthed to the disc 76 at 95 is a thin resilient metal strip 82 passing centrally across the disc and connected to a pin 86 extending from one side of a flexible diaphragm 84 housed in the disc. On the opposite side of the diaphragm there extends a pin 87 which is engageable in a groove 89 in an arcuate raised cam portion 88 on the worm wheel 23. Centrally on the disc 76 is mounted an insulated plate 92 carrying a metallic strip provided with a tab 93 and a contact 91 engageable with the strip 82. In operation a manual switch 96<SP>1</SP>, Fig. 10, causes the continual energisation of the motor 19 and its field coils 98 from a source 97, via conductor 96, tab 93 and conductor 97 to earth. An alternative path to earth in parallel with the switch 96<SP>1</SP> is afforded by the contact 91, strip 82 and correction 95. When the switch 96<SP>1</SP> is opened the motor continues to operate until the cam causes the strip 82 to separate from the contact 91. The motor is then brought to rest with the wipers in a parked position. The disc 76 can be rotated in the housing 22 by means of a tab (not shown), to allow for adjusting the parking position of the wipers. |
