Electromagnetic switch means for a flow control device and the like having reduced shock levels

• US 4,236,132 A
• Filed: 02/12/1979
• Issued: 11/25/1980
• Est. Priority Date: 02/12/1979
• Status: Expired due to Term

• Current Assignee: Baxter Travenol Laboratories Incorporated
• Original Assignee: Baxter Travenol Laboratories Incorporated
• Inventors: Zissimopoulos, Nicholas
• Primary Examiner(s): Broome, Harold
• Application Number:
  US06/011,250
• Time in Patent Office: 652 Days
• Field of Search: 335/81, 335/86, 335/90, 335/104, 335/105, 335/193, 335/194, 335/247, 335/248, 335/270, 335/271, 335/273, 335/276, 335/277, 335/234, 335/236, 335/229, 335/230, 335/46, 335/157 , 335/257
• US Class Current: 335/271
• CPC Class Codes: H01F 7/14 Pivoting armatures H01F7/17 takes precedence
• CPC Class Codes: H01H 50/305 damping vibration due to functional movement of armature in air-gap H01H50/163

Abstract

An electromagnetic switch which comprises an armature pivotally movable between first and second pivotal positions about a fulcrum positioned between its ends. Magnet means are positioned adjacent each of the armature ends and present opposite polarities outwardly from each end of the armature. Electromagnet core means define arms positioned adjacent the magnet means at each armature end, with the magnet means being each respectively movable toward and away from an arm when pivoting between the first and second pivotal positions. The armature can be moved between the first and second positions by changing the polarity of the electromagnet core means. In accordance with this invention, restraining means engagable with the armature for preventing the armature from pivoting into contact with the electromagnet core means are provided for prevention of noise and for preservation of the life of the magnet means.

Claims

1. In an electromagnetic switch which comprises an armature pivotally movable between first and second pivotal positions about a fulcrum positioned between its ends, separate magnet means positioned at each end of said armature presenting opposite polarities outwardly from each end of the armature, and electromagnet core means, actuated by a single coil, defining arms of common polarity positioned adjacent said magnet means at each armature end, said magnet means being each respectively movable toward and away from an arm when pivoting between said first and second pivotal positions, whereby said armature can be moved between said first and second positions by changing the polarity of said electromagnet core means, and restraining means engagable with said armature for preventing the ends of said armature from pivoting into contact with said electromagnet core means, said restraining means comprising a pair of brackets, each carried by an arm of the electromagnet core means, each bracket being adapted to engage a side of said armature opposed to said electromagnet core means in one of said first and second pivotal positions.

2. The switch of claim 1 in which said restraining means engages said armature with a padded surface to reduce the noise of operation of said switch.

3. The switch of claim 2 in which each bracket is adjustably positionable to permit adjustment of the minimum and maximum spacings between each armature end and each arm of the electromagnet core means in the first and second positions.

4. The switch of claim 3 in which said minimum spacings are 0.002 to 0.005 inch.

5. The switch of claim 3 in which the minimum spacings between each armature end and the associated arm of the electromagnet core means are adjusted so that the magnetic fields between each armature end and associated arm at said minimum spacings are of essentially equal strength.

6. The switch of claim 3 in which said padded surface is defined by a rubber pad carried by said bracket means.

7. In an electromagnetic switch which comprises an armature pivotally movable between first and second pivotal positions about a fulcrum positioned between its ends, separate magnet means positioned adjacent each end of said armature presenting opposite polarities outwardly from each end of the armature, and electromagnet core means carrying a single coil and defining arms of common polarity positioned adjacent said magnet means at each armature end, said magnet means being each respectively movable toward and away from an arm when pivoting between said first and second pivotal positions, whereby said armature can be moved between the first and second positions by changing the polarity of said electromagnetic core means, restraining means engagable with said armature for preventing the ends of said armature from pivoting into contact with said electromagnet core means, said restraining means being adapted to engage said armature with a padded surface to reduce the noise of operation of said switch, said restraining means being adjustably positionable to permit adjustment of the minimum and maximum spacings between each armature end and each arm of the electromagnet core means in the first and second positions, the minimum spacings between each armature end and the associated arm of the electromagnet core means being adjusted so that the magnetic fields between each armature and associated arm at said minimum spacings are of essentially equal strength.