Contamination protected electrical switch, particularly automotive ignition breaker contact structure
AssigneeRobert Bosch GmbH
InventorDieter Betz
Life of this patent
Estimating the term…
Abstract
To improve the operating reliability and accuracy of ignition breaker contacts, an operating rod passes into a sealed housing, in gas-tight manner, by being secured, gas-tight, to a membrane which is resiliently deflectable, the breaker rod reciprocating under control of an engine operating cam, the membrane effecting a gas-tight seal while, by resilient deflection, transferring operating movement into the interior of the breaker switch housing; the breaker contacts are retained in the housing. A spring is used to provide for operating force, or the membrane may be pre-stressed; the interior of the housing may be evacuated or may contain a protective, inert gas.
Claims25
Contamination protected electrical switch having a closed, cup-shaped housing (15, 16, 22, 30) having a cap portion (16) and an apertured base plate portion (15);
- a fixed contact (13) located in the housing;
- a movable contact (10) located in the housing;
- an operating rod (11) passing through the apertured base plate portion of the housing and thereinto, the movable contact (10) being operated by the operating rod, the operating rod being reciprocable from outside of the housing to effect engagement and disengagement of the movable contact from the fixed contact,
- a membrane (21, 27, 34, 36, 38) gas-tightly sealed to the cap portion of the housing to define a sealed chamber in the cap portion of the housing, the membrane being further gas-tightly sealed to the operating rod (11) to provide for gas-tight passage of the operating rod into the housing without leakage and permit reciprocating movement of the operating rod by deflection of the membrane;
- and a spring (17) located within the cap portion and exerting a bias force on the movable contact (10) and cooperating with the force due to pressures within the sealed chamber and operating forces applied to the operating rod (11) to provide, by interaction of said operating forces, for opening and closing of the contacts.
Dependencies are inferred from the claim text.