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US3941954A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic captive key switch lock

Assignee: Individual
•
Filing: 1974-09-10
•
Granted: 1976-03-02
•
Expires: 1994-09-10
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Abstract

Abstract A cylinder and plug type lock mechanism drivingly connects an authorized key to the actuator of a switch device and captivates the key when turning the switch on. A magnetic latch activated in the captive position of the key, prevents return of the key to its release position. A magnetic release element is positioned on the key against the lock mechanism to disengage the magnetic latch.

Inventors

  • 👤 Robert E. Wintringham

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 20:26
CPC Classifications
E; E05; E05B; E05B47/00; E05B47/0038; E05B47/0044; H; H01; H01H; H01H21/00; H01H21/02; H01H21/18; Y; Y10; Y10T; Y10T70/00; Y10T70/70; Y10T70/7051; Y10T70/7057; Y10T70/7441; Y10T70/7446; Y10T70/7458; Y10T70/7486; Y10T70/7508; Y10T70/7559; Y10T70/7565; Y10T70/7768

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 126 words
In combination with a lock mechanism having a tubular housing and a plug angularly displaceable by an authorized key from a release position in which said key is received in a keyway formed in the plug to a captive position in which the key cannot be withdrawn from the keyway, means for releasably preventing withdrawl of said key from the lock mechanism, comprising latch means automatically activated in response to positioning of the plug in the captive position for preventing angular displacement of the plug by said key to the release position, and release means operatively positioned in non-rotative relation on the key in the captive position of the plug for magnetically releasing the latch means to permit displacement of the plug to the release position.
Claim 2
Dependent Claim 126 words
In combination with a lock mechanism having a tubular housing and a plug angularly displaceable by an authorized key from a release position in which said key is received in a keyway formed in the plug to a captive position in which the key cannot be withdrawn from the keyway, means for releasably preventing withdrawl of said key from the lock mechanism, comprising latch means automatically activated in response to positioning of the plug in the captive position for preventing angular displacement of the plug by said key to the release position, and release means operatively positioned in non-rotative relation on the key in the captive position of the plug for magnetically releasing the latch means to permit displacement of the plug to the release position.
Claim 3
Dependent Claim 70 words
The combination of claim 1 wherein said latch means includes a face cap member secured to the housing, a latch member secured to the plug in confronting relation to the face cap member, and a magnetic element movably mounted by one of said members, the other of said members having a cavity into which the magnetic element is projected by magnetic force only in the captive position of the plug.
Claim 4
Dependent Claim 59 words
The combination of claim 2 wherein said release means comprises a release element having a slot adapted to straddle the key in abutment with the face cap member, and a magnetic means embedded in the release element in operative alignment with the magnetic element in the captive position of the plug for retracting the magnetic element from the cavity.
Claim 5
Dependent Claim 45 words
The combination of claim 3 wherein said latch member comprises a flange connected to the plug in slide bearing contact with the face cap member and within which said cavity is formed when aligned with the magnetic element in the captive position of the plug.
Claim 6
Dependent Claim 43 words
The combination of claim 4 including fixed terminal means connected to the housing, a switch actuator drivingly connected to the plug and contact means carried by the actuator for engagement with the terminal means in only one of said positions of the plug.
Claim 7
Dependent Claim 45 words
The combination of claim 2 wherein said latch member comprises a flange connected to the plug in slide bearing contact with the face cap member and within which said cavity is formed when aligned with the magnetic element in the captive position of the plug.
Claim 8
Dependent Claim 43 words
The combination of claim 1 including fixed terminal means connected to the housing, a switch actuator drivingly connected to the plug and contact means carried by the actuator for engagement with the terminal means in only one of said positions of the plug.
Claim 9
Dependent Claim 88 words
In combination with an operating mechanism actuated through a lock mechanism by an authorized key in response to angular displacement thereof from an inactive position to an actuated position, said lock mechanism receiving said key in the inactive position and captivating the key in the actuated position, magnetic latch means automatically activated in the actuated position of the key for preventing return of the key to the inactive position and magnetic release means non-rotatively positioned on the key for disengaging the magnetic latch means in the actuated position.
Claim 10
Dependent Claim 88 words
In combination with an operating mechanism actuated through a lock mechanism by an authorized key in response to angular displacement thereof from an inactive position to an actuated position, said lock mechanism receiving said key in the inactive position and captivating the key in the actuated position, magnetic latch means automatically activated in the actuated position of the key for preventing return of the key to the inactive position and magnetic release means non-rotatively positioned on the key for disengaging the magnetic latch means in the actuated position.
Claim 11
Dependent Claim 13 words
The combination of claim 8 wherein said operating mechanism is a switch device.

References Cited (Backward Citations)

GB805645A Cited
US2856474A Cited
US3518855A Cited
US3639708A Cited
US3729964A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-02 1979-09-01 1980-03-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-02 1983-09-01 1984-03-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-02 1987-09-01 1988-03-02 $7700.00 Window Closed / Lapsed

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