| 摘要 |
<p>1,089,961. Valves; stopping shafts in predetermined positions. ELECTRICAL REMOTE CONTROL CO. Ltd., and J. CHUCHLA. Aug. 28. 1964 [Aug. 30, 1963], No. 34378/63. Headings F2L and F2V. An automatic timer comprises a miniature pneumatic motor 1, and a cam-shaft 14 driven thereby to operate miniature pneumatic snap-acting control valves 21. The rotary propeller of the motor 1 continuously drives a gear 8 through a gear train 5 and upon supplying air to a cylinder 30 the piston 29 therein tensions springs 26, 28 and a lever 25 engages a resiliently faced clutch 10, 11 to connect the gear 8 to the cam-shaft 14 as well as to operate a three-armed lever 31 which tilts a plate 35 to lower cam follower 19 on to adjustable cams 15 thereby operating valves 21 in a given sequence. Each cam carries a calibrated scale. When the air supply to the cylinder 30 is cut-off the piston 29, clutch 10, 11, and other parts return to the inoperative position. Another cam 39 on the shaft 14 coacts with a spring-loaded arm 40 pivoted in a drum 43 and if the arm 40 does not lie in the cam cusp then shaft 14 is returned to an angular preset location determined by the angular position of the arm 40 around the shaft; manual or pneumatic motor rotation of the drum varies this angular position. A pointer 45 on the shaft 14 moves over a scale 46 on the drum. The clutch and resetting arrangement may be omitted in which case the shaft 14 is driven directly from the motor 1.</p> |
