# US 4,394,556 A · Cam operated switch assembly

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 4,394,556 A
- Document ID: US4394556A
- Status: Granted
- Kind: A
- Application number: 06/352,822
- Filed: 1982-02-26
- Granted: 1983-07-19
- Earliest claimed: 1982-02-26
- Assignees: The United States of America as represented by the Secretary of the Navy
- Inventors: Gilbert Gould
- Web page: https://patentgrep.com/patent/US4394556A

## CPC

- H01H 3/42: using cam or eccentric
- H01H 17/00: Switches having flexible operating part adapted only for pulling, e.g. cord, chain {(for emergency stop switches H01H3/0226)}
- H01H 3/20: wherein an auxiliary movement thereof, or of an attachment thereto, is necessary before the main movement is possible or effective, e.g. for unlatching, for coupling
- H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00)

## Abstract

A switch assembly is provided for connecting a battery to an electronic ambly which is part of a sonobuoy which is deployed from an aircraft. A normally-closed micro-switch is connected in a battery circuit and a rotatable cam depresses a lever arm on the micro-switch to open the circuit. A lanyard, having one end attached to an aircraft, is attached to the rotatable cam and launching of the sonobuoy causes the lanyard to rotate the cam and release the lever arm of the micro-switch. A safe pin prevents rotation of the cam until the safe pin is removed prior to launch.

## Claims

### Claim 1

A switching system for connecting battery power to an electronic unit comprising,
a normally-closed switch having an operable lever arm,
a rotatable cam having a curved surface for depressing said lever arm to open said switch,
a lanyard,
means in said cam for releasably attaching one end of said lanyard thereto, and
means engageable with said cam for preventing rotation of said cam.

### Claim 2 (depends on 1)

A switching system for connecting battery power to an electronic unit as set forth in claim 1 wherein said means in said cam for releasably attaching one end of said lanyard thereto comprises an open-ended slot extending from an edge of said cam.

### Claim 3 (depends on 2)

A switching system for connecting battery power to an electronic unit as set forth in claim 2 wherein said cam has a flat surface thereon adjacent said curved surface and wherein said means for preventing rotation of said cam comprises a safe pin in abutment with said flat surface.

### Claim 4 (depends on 3)

A switching system for connecting battery power to an electronic unit as set forth in claim 3 wherein said open-ended slot extends from said flat surface and said safe pin closes said slot to prevent disengagement of lanyard from said slot until said safe pin is removed.

### Claim 5 (depends on 1)

A switching system for connecting battery power to an electronic unit as set forth in claim 1 having a stop pin for preventing rotation of said cam in one direction.

### Claim 6 (depends on 1)

A switching system for connecting battery power to an electronic unit as set forth in claim 1 having spring means biasing said cam against rotation until said cam is rotated by a force applied to said lanyard.

### Claim 7

A switching system for connecting battery power to an electronic unit comprising,
a normally-closed switch having an operable lever arm,
a rotatable cam having a curved surface for depressing said lever arm to open said switch and having a first flat surface adjacent said curved surface,
a lanyard,
an open-ended slot in said cam extending from said first flat surface for removably holding one end of said lanyard, and
a safe pin in abutement with said first flat surface for preventing rotation of said cam, said safe pin closing said slot to prevent disengagement of said lanyard from said slot until said safe pin is removed.

### Claim 8 (depends on 7)

A switching system for connecting battery power to an electronic unit as set forth in claim 7 having a stop pin for preventing rotation of said cam in one direction.

### Claim 9 (depends on 7)

A switching system for connecting battery power to an electronic unit as set forth in claim 7 having spring means biasing said cam against rotation until said cam is rotated by a force applied to said lanyard.