Control switch for a fluid pressure system

Abstract

Abstract 1,089,305. Fluid actuation of switches. SPEED DEVELOPMENT CO. Ltd. May 31, 1966 [May 31, 1965], No. 23138/65. Heading H2B. [Also in Division G3] A switch, e.g. for controlling an aircraft hydraulic system or a pump, includes a movable contact 20 carried by a lever 15 pivotable at 13 and actuated through a ball 16 and a piston 3 by pressure on a steel diaphragm 7. When pressure is not supplied to inlet 11, contact 20 engages a fixed contact 21, and as pressure is gradually applied, contact 20 breaks with contact 21 and makes with a fixed contact 22. Contacts 20, 21, 22 are connected in circuit with two relays (28, 29, Figs. 2, 5), and when contacts 20 and 22 make, one relay (29) is energized and a signal is produced at a terminal (32). As the pressure decreases, contacts 20 and 22 break, but the one relay (29) remains energized. On further pressure decrease, contacts 20 and 21 make, the other relay (28) is energized, the one relay (29) is de-energized, and the signal is removed from the terminal (32). The signal can also be produced at break. The two relays can be replaced by a single relay. Piston 3 is mounted in a bore 2 by adjustable lock-nuts 5 and its movement is limited by shoulders 4, 6. A rubber disc 33 is provided between the piston and the diaphragm. Contacts 21, 22 are carried by spring arms, the arm of contact 22 being screw adjustable. Contact 20 is adjustable by a screw 17 and springs 18, 19 acting on lever 15.

Inventors

• 👤 Gould Percy
• 👤 Firmager Derek

Bibliographic Details