AU701294B3

AU701294B3 - Electromagnetic lock

Info

Publication number: AU701294B3
Application number: AU70060/98A
Authority: AU
Inventors: Zhi-Chung Chang
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-06-10
Filing date: 1998-06-10
Publication date: 1999-01-21
Anticipated expiration: 2004-06-10
Also published as: FR2780085B3; FR2780085A3

Description

-rl 1 Electromagnetic Lock The present invention relates to an electromagnetic lock. More particularly, the present invention relates to an electromagnetic lock which is easily assembled.

Referring to Fig. 1, a conventional electromagnetic lock 11 is disposed in a doorcase 1. A frame 15 is disposed in a door plank 13. A metal plate 14 is disposed in the frame 15. Two bolts 16 fasten the metal plate 14 in the frame 15. Each bolt 16 is surrounded by a spring 18. The conventional electromagnetic lock 11 comprises an extended rib 12. The metal plate 14 has a recess 17 receiving the extended rib 12.

When the doorcase 1 contacts the door plank 13, the electric current will circulate.

Therefore, the conventional electromagnetic lock 11 attracts the metal plate 14.

However, the door plank 13 may be slant after a long period of usage. Thus the recess 17 will not match the extended rib 12.

It is the object of the present invention to overcome or substantially ameliorate the above disadvantages.

15 There is disclosed herein an electromagnetic lock comprising: Soan electromagnetic plate having two protrusions disposed on a bottom surface thereof; an iron plate being mounted to a frame, the plate including two transverse •grooves at top surface thereof, each adapted to engage the protrusions when said lock is 20 in use, each groove having a recess at a central portion thereof, a further recess being formed in the plate and receiving a spring which bears against a post which extends through the plate, the post being restrained to said plate by means of a C-shaped washer; wherein the iron plate is mounted to the frame by two mounting recesses formed on a bottom surface of the iron plate, two corresponding holes formed on said frame, a mounting bolt disposed in each of said corresponding holes, heads of each mounting bolt being received in the corresponding mounting recess, an annular washer being disposed between the head of each bolt and the frame, each washer being attached to a notch formed on the bottom surface of the plate and a spring surrounding the shank of each bolt and being disposed between the washer and the frame.

Fig. 1 is a schematic view illustrating an application of a conventional electromagnetic lock of the [N:\LIBLL]O2132:PVH prior art; FIG. 2 is a perspective exploded view of an electromagnetic lock of a preferred embodiment in accordance with the present invention; FIG. 2A is a sectional view of an electromagnetic plate; FIG. 2B is a partially enlarged view of a groove; FIG. 3 is a schematic view illustrating a combination of an electromagnetic plate and a frame of a preferred embodiment in accordance with the present invention; "FIG. 4 is a schematic view illustrating a combination of an electromagnetic plate and a frame of another preferred embodiment in accordance with the present invention; 15 FIG. 5 is a schematic view illustrating an application of two electromagnetic locks of a preferred embodiment in accordance with the present invention; FIG. 6 is a schematic view illustrating another application of an electromagnetic lock of a preferred embodiment in accordance with the present invention; FIG. 7 is a sectional schematic view illustrating an operation of an electromagnetic lock of a preferred embodiment while an electric current is discontinued; FIG. 7A is a partially enlarged view of a protruded tooth and a recess hole in FIG. 7; FIG. 7B is a partially enlarged view of a head, a post and a compression spring in FIG. 7; FIG. 8 is a sectional schematic view illustrating an operation of an electromagnetic lock of a preferred embodiment while an electric current is continued; and FIG. 8A is a partially enlarged view of a bolt, a coiled spring and a notch in FIG. 8.

Referring to FIGS. 2, 2A, 2B, 3, 7, 7A, 7B, 8 and 8A, an electromagnetic lock comprises an electromagnetic plate 2, an iron plate 3, and a frame 4. Two protruded teeth 21 are disposed on a bottom of the electromagnetic plate 2. The iron plate 3 has a post 351, two round holes 37, two grooves 31 matching the protruded teeth 21, a center hole 341 receiving a C-shaped washer 15 36, a compression spring 342 and the post 351, two bottom notches 372, and two recess holes 32 communicating with the grooves 31. The frame 4 has two through holes 41 matching the round holes 37. Two bolts 38 are inserted through the round holes 37 and disposed between the electromagnetic plate 2 and the frame 4. Each bolt 38 is surrounded by a coiled spring 39 and an annular washer 381. Each annular washer 381 is inserted in the respective bottom notch 372 and fastened by screws 382.

Each round hole 37 and each bottom notch 372 are communicated with a through aperture 371 to receive the respective bolt 38. Each recess hole 32 receives the respective protruded teeth 21. Two studs 22 fasten the electromagnetic plate 2 on an article such as a doorcase i.

FIG. 7 is a sectional schematic view illustrating an operation of an electromagnetic lock of a preferred embodiment while an electric current is discontinued.

FIG. 8 is a sectional schematic view illustrating an operation of an electromagnetic lock of a preferred embodiment while an electric current is continued.

Referring to FIG. 5, an application of two electromagnetic locks are illustrated.

Referring to FIG. 6, an application of an electromagnetic lock is illustrated.

Referring to FIG. 4, the frame 5 is in a U-shape.

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.9 The claims defining the invention are as follows: 1. An electromagnetic lock comprising: an electromagnetic plate having two protrusions disposed on a bottom surface thereof; an iron plate being mounted to a frame, the plate including two transverse grooves at top surface thereof, each adapted to engage the protrusions when said lock is in use, each groove having a recess at a central portion thereof, a further recess being formed in the plate and receiving a spring which bears against a post which extends through the plate, the post being restrained to said plate by means of a C-shaped washer; wherein the iron plate is mounted to the frame by two mounting recesses formed on a bottom surface of the iron plate, two corresponding holes formed on said frame, a mounting bolt disposed in each of said corresponding holes, heads of each mounting bolt being received in the corresponding mounting recess, an annular washer 15 being disposed between the head of each bolt and the frame, each washer being attached to a notch formed on the bottom surface of the plate and a spring surrounding the shank of each bolt and being disposed between the washer and the frame.

S 2. The electromagnetic lock of claim 1 substantially as hereinbefore 9 described with reference to Figs. 2 to 3, 5 and 7 to 8A; or Figs. 2 to 2B, 4, 6 and 7 to S 20 8A; of the accompanying drawings.

Dated 7 December, 1998 S" Zhi-Chung Chang Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON [N:\LIBLL]02132:PVH