Electromagnetic lock for cylindrical lock barrel

• US 5,561,997 A
• Filed: 04/20/1995
• Issued: 10/08/1996
• Est. Priority Date: 02/08/1993
• Status: Expired due to Fees

• Current Assignee: Marlok Company
• Original Assignee: Marlok Company
• Inventors: Milman, Sheldon
• Primary Examiner(s): Boucher, Barnell M.
• Application Number:
  US08/426,429
• Time in Patent Office: 537 Days
• Field of Search: 70/276, 70/DIG. 62, 70/419, 70/421, 70/277, 70/278, 70/283
• US Class Current: 70/283
• CPC Class Codes: E05B 47/0006 having a non-movable core; with permanent magnet
• CPC Class Codes: E05B 47/063 with a rectilinearly moveable blocking element
• CPC Class Codes: Y10S 70/62 Cylinder plug stop
• CPC Class Codes: Y10T 70/7062 Electrical type [e.g., solenoid]
• CPC Class Codes: Y10T 70/713 Dogging manual operator
• CPC Class Codes: Y10T 70/7944 Guard tumbler

Abstract

A cylindrical barrel type lock wherein rotation of the barrel is prevented by one or more armatures which are actuated by an electromagnet. Energization of the electromagnet causes the armatures to be withdrawn from engagement with the barrel, thereby permitting its rotation to open the lock.

Claims

1. A cylindrical lock including an outer shell having a cylindrical bore therein for receiving for rotation therein a cylindrical barrel having a cylindrical outer surface, said cylindrical barrel having an axially extending slot formed therein for receiving a key to unlock and rotate said cylindrical barrel in said cylindrical bore, a major axis of a cross-section of said slot coinciding with a diameter of said cylindrical barrel, said outer shell having a first cavity formed therein for receiving an electromagnet, the central axis of said first cavity being in alignment with a diameter of said cylindrical bore, at least a second cavity extending from said first cavity to said cylindrical bore, the central axis of said second cavity being offset from and parallel to the center axis of said first cavity,

said barrel having at least one notch formed in said outer surface, which notch is offset from said diameter of said cylindrical barrel which coincides with the major axis of the cross-section of said slot and may be positioned in alignment with said second cavity,

an armature receiving in said second cavity, a portion of said armature in a first position extending from said second cavity into said at least one notch in said barrel to thereby prevent rotation of said barrel in said cylindrical bore, energization of said electromagnet being effective to move said armature to a second position wherein said portion of said armature is retracted from said notch in said barrel, whereby said barrel is free to rotate in said cylindrical bore, said second cavity, said notch and said armature being arranged such that said armature is subjected to compression forces in said first position upon rotation of said barrel.

2. The cylindrical lock of claim 1, wherein said second cavity and said armature have the same cross-sectional shape.

3. The cylindrical lock of claim 2, wherein said cross-sectional shape is longer in the direction of the major axis of said bore than in the direction perpendicular to the major axis of said bore.

4. The cylindrical lock of claim 1, wherein a force providing means urges said armature into said first position, and energization of said electromagnet is effective to overcome the force provided by said force providing means to move said armature to said second position wherein said portion of said armature is retracted from said notch in said barrel.

5. The cylindrical lock of claim 4, wherein said force providing means is a spring.

6. The cylindrical lock of claim 4, wherein said force providing means is a conical spring.

7. The cylindrical lock of claim 1, wherein said notch is formed by two planar sides at right angles to each other, one of said sides being parallel to and spaced from a plane which passes through said diameter of said cylindrical barrel which coincides with the major axis of the cross-section of said slot.

8. The cylindrical lock of claim 7, wherein said armature is provided with two planar sides at right angles to each other, which engage said two planar side of said notch when said armature is extended into said notch.

9. The cylindrical lock of claim 1, wherein said armature is provided with a surface which engages a portion of the cylindrical surface of said barrel when said armature extends into said notch.

10. The cylindrical lock of claim 1, wherein two second cavities extend from said first cavity to said cylindrical bore, said second cavities being offset on opposite sides from said diameter of said cylindrical barrel which coincides with the major axis of the cross-section of said slot,

said barrel having two notches formed in said outer surface which may be positioned in alignment with said two second cavities,

two armatures, one received in each of said second cavities, a portion of each of said armatures in first positioned extending from said second cavities into one of said notches in said barrel to thereby prevent rotation of said barrel in said cylindrical bore, energization of said electromagnet effective to move said armatures to second positions wherein said portions of said armatures are retracted from said notches in said barrel, whereby said barrel is free to rotate in said cylindrical bore, said second cavities, said notches and said armatures being arranged such that at least one of said armatures is subjected to compression forces in said first position upon rotation of said barrel.

11. The cylindrical lock of claim 10, wherein said second cavities and said armatures have the same cross-sectional shape.

12. The cylindrical lock of claim 11, wherein said cross-sectional shapes are longer in the direction of the major axis of said bore than in the direction perpendicular to the major axis of said bore.

13. The cylindrical lock of claim 10, including a pair of force providing means, one of said force providing means urging one of said armatures and the other of said force providing means urging the other of said armatures into said first positions, and energization of said electromagnet being effective to overcome the forces provided by said force providing means to move said armatures to said second positions wherein said portions of said armatures are retracted from said notches in said barrel.

14. The cylindrical lock of claim 13, wherein said force providing means are springs.

15. The cylindrical lock of claim 13, wherein said force providing means are helical springs.

16. The cylindrical lock of claim 10, wherein said notches are each formed by two planar sides at right angles to each other, one of said sides being parallel to and spaced from a plane which passes through said diameter of said cylindrical barrel which coincides with the major axis of the cross-section of said slot.

17. The cylindrical lock of claim 16, wherein each of said armatures is provided with two planar sides at right angles to each other, which engage said two planar sides of one of said notches when said armatures is extended into said notch.

18. A lock comprising:

a cylinder;

a core rotatably received within a bore in said cylinder;

at least one armature movable between a first position which prevents said core from rotating relative to said cylinder and a second position which allows said core to rotate relative to said cylinder; and

a magnetic device operatively associated with said at least one armature to move said at least one armature between said first and second positions;

said cylinder including a cavity in which said at least one armature is received in both said first and second positions;

said core having a notch in which said at least one armature is received in said first position,

said cavity, notch and armature being configured such that said at least one armature is subjected to compression forces by opposed faces in said cavity and said notch while in said first position upon rotation of said core.

19. The lock of claim 18, wherein in cross section said core and cylinder have coincident vertical and horizontal axes,and said cavity is configured such that along a line parallel to said horizontal axes at a bottom wall of said notch, said cavity extends horizontally into said cylinder.

20. A lock comprising:

a cylinder;

a core rotatably received within a bore in said cylinder;

at least two armatures movable parallel to each other between a first position which prevents said core from rotating relative to said cylinder and a second position which allows said core to rotate relative to said cylinder; and

at least one magnetic device operatively associated with said at least two armatures to move said armatures between said first and second positions;

said cylinder including corresponding cavities in which said armatures are received in both said first and second positions;

said core having at least two notches corresponding to said at least two armatures and in which said armatures are engaged in said first position, said cavities, notches and armatures being configured such that when in said first position, one of said armatures is laterally compressed between opposed faces of the associated cavity and notch upon application of torque to the core in one rotational direction, and such that the other armature is laterally compressed between a opposed face of its respective notch and cavity upon application of torque to the core in an opposite rotational direction.

21. The lock of claim 20, wherein in cross section said core and cylinder have coincident vertical and horizontal axes, and said cavities are positioned on opposite sides of said vertical axis and configured such that along a line parallel to said horizontal axes at bottom walls of said notches, said cavities extend horizontally into said cylinder.

22. A lock comprising:

a cylinder having a bore;

a barrel rotatably received in the cylinder bore;

a pair of notches formed in an outer circumference of the barrel, the notches being spaced circumferentially from each other;

a pair of cavities formed in the cylinder, each cavity aligning with a respective notch when the core is rotated to predetermined position;

a pair of armatures, each armature being received within one of the cavities, the armatures being moveable in a parallel manner between first and second positions, each armature being laterally compressed between a wall of the respective notch and an opposing wall of the corresponding cavity when in the first position to prevent rotation of the barrel, the armatures being retracted from the notches and positioned only within the cavities when in the second position; and

a magnetic device operative to move the armatures between the first and second positions.