Claims
- 1. Switching apparatus for selectively completing or interrupting an electrical connection between an input and an output conductor comprising:
- a armature movable between first and second positions,
- an electromagnet adapted, when energized, to move said armature from the first position to the second position, said armature being unresponsive to said electromagnet when in said second position,
- an input contact connected to said input conductor,
- an output contact connected to said output conductor,
- rocking means rotatable in response to movement of said armature, one of said contacts being mounted on said rocking means and rotatable therewith into engagement with the other of said input and output contacts when said armature is moved from said second position to said first position and out of engagement with said other of said input and output contacts when said armature is moved from said first position to said second position,
- a pressure sensitive member connected to said armature for moving said armature to said first position from said second position when operability is desired, said armature being inoperable in response to teasing pressure when in said first position,
- a differential transformer for generating a voltage pulse in response to a current imbalance,
- a circuit operatively connected to said differential transformer for integrating said voltage pulse, said circuit including a silicon controlled rectifier electrically connected to said electromagnet, said silicon controlled rectifier being caused to conduct current in response to a given magnitude and duration of the integrated voltage pulse thereby energizing said electromagnet to cause said armature to open said one contact for interrupting said electrical connection between said input and output conductors.
- 2. Apparatus according to claim 1 further comprising latching means electrically connected to said silicon controlled rectifier and said electromagnet for maintaining said armature in said first position, said latching means releasing said armature from said first position when said electromagnet is energized.
- 3. Apparatus according to claim 2 wherein said latching means comprises a frame having a slot with a shoulder formed therein, said armature being rotatably connected to said pressure sensitive member and slidably mounted in said slot, said armature being latched against said shoulder when in said first position and pivoting with respect to said pressure sensitive member when said electromagnet is energized to separate from said shoulder and move to said second position.
- 4. Apparatus according to claim 3 further comprising a spring connected at one end to said armature and at the other end to said frame, the axis of said spring being oblique to the plane of said armature, said spring exerting a force on said armature having parallel and transverse components for urging said armature into said first position when said pressure sensitive member is depressed and for urging said armature into said second position when said armature is moved in opposition to said transverse spring force component in response to energization of said electromagnet.
Parent Case Info
This is a continuation of application Ser. No. 940,224 filed Sept. 7, 1978 now U.S. Pat. No. 4,412,193.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
3864649 |
Doyle |
Feb 1975 |
|
4086549 |
Slater et al. |
Apr 1978 |
|
4209762 |
Samborski et al. |
Jun 1980 |
|
4412193 |
Bienwald et al. |
Oct 1983 |
|
Continuations (1)
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Number |
Date |
Country |
Parent |
940224 |
Sep 1978 |
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