Resiliently mounted strike plate of an electromagnetic door lock

Patent metadata

Field	Value
Publication number	US-2019071892-A1
Application number	US-201816180438-A
Country	US
Kind code	A1
Filing date	Nov 5, 2018
Priority date	Apr 14, 2016
Publication date	Mar 7, 2019
Grant date	—

Abstract

A strike plate mounting bolt assembly for resiliently mounting a strike plate to a door. The strike plate mounting bolt assembly includes a bolt and a post wherein the bolt is securably engageable with the post. The bolt is inserted through a bore in the door and the post is inserted through a bore in the strike plate. A resilient member such as at least one Belleville washer is disposed between a head of the post and a cavity in the strike plate wherein the at least one Belleville washer is compressed between the post head and cavity upon securing the bolt and post together to provide a resilient mount between the door and strike plate. The at least one Belleville washer may be a number of Belleville washers selectable stacked to form a pack of Belleville washers. By varying the number and orientation of the Belleville washers, the force/deflection characteristics of the pack may be tuned to accommodate the needs of a variety of electromagnetic lock design features.

First claim

1 . An electromagnetic lock having a strike plate that is resiliently mountable to a door, said lock comprising:
a) an energizable electromagnet mountable to a door frame; b) said strike plate includes a first through bore, an inner surface facing said door, and an outer surface facing said energizable electromagnet; and c) a strike plate mounting bolt assembly for resiliently mounting said strike plate to said door, said strike plate mounting bolt assembly comprising:
i) a bolt configured to be received in a second through bore in said door;
ii) a post connected to said bolt, wherein said post includes a head end and a shaft end opposite said head end, wherein said head end is oriented distal from said inner surface of said strike plate and proximate said outer surface of said strike plate when said strike plate is mounted to said door; and
iii) a resilient member received by said head end of said post and said strike plate for resiliently mounting said strike plate to said door.

2 . The electromagnetic lock of claim 1 wherein said post is configured to be received in said first through bore in said strike plate.

3 . The electromagnetic lock of claim 1 wherein said resilient member is at least one Belleville washer.

4 . The electromagnetic lock of claim 1 wherein said strike plate includes a cavity concentric with said first through bore, and wherein said resilient member is received in said cavity.

5 . The electromagnetic lock of claim 1 wherein said bolt includes a head, and wherein said head is configured to abut a rear face of said door.

6 . The electromagnetic lock of claim 1 wherein said bolt includes a shaft, and wherein said shaft end of said post is configured to be threadably received by said shaft of said bolt.

7 . An electromagnetic lock having a strike plate that is resiliently mountable to a door, said lock comprising:
a) an energizable electromagnet mountable to a door frame; b) said strike plate includes a first through bore, an inner surface facing said door, and an outer surface facing said energizable electromagnet; and c) a strike plate mounting bolt assembly for resiliently mounting said strike plate to said door, said strike plate mounting bolt assembly comprising:
i) a first fastening member configured to be received in a second through bore in said door;
ii) a second fastening member connected to said first fastening member, wherein said second fastening member includes a head end and a shaft end opposite said head end, wherein said head end is oriented distal from said inner surface of said strike plate and proximate said outer surface of said strike plate when said strike plate is mounted to said door; and
iii) a resilient member received by said head end of said second fastening member and said strike plate for resiliently mounting said strike plate to said door.

8 . The electromagnetic lock of claim 7 wherein said second fastening member is configured to be received in said first through bore in said strike plate.

9 . The electromagnetic lock of claim 7 wherein said resilient member is at least one Belleville washer.

10 . The electromagnetic lock of claim 7 wherein said strike plate includes a cavity concentric with said first through bore, and wherein said resilient member is received in said cavity.

11 . The electromagnetic lock of claim 7 wherein said first fastening member includes a head, and wherein said head is configured to abut a rear face of said door.

12 . The electromagnetic lock of claim 7 wherein said first fastening member includes a shaft, and wherein said shaft end of said second fastening member is configured to be threadably received by said shaft of said first fastening member.

13 . A method of tuning force/deflection characteristics of a strike plate mounting bolt assembly for resiliently mounting a strike plate to a door, said method comprises the steps of:
providing a collection of Belleville washers, each having a certain force/deflection characteristic; determining the force/deflection characteristics needed to permit a predetermined amount of movement of said door in an opening direction while said strike plate remains in contact with an energized electromagnet; selecting a resilient member stack comprising two or more Belleville washers from the collection of Belleville washers in accordance with the determined force/deflection characteristics; and assembling the strike plate mounting bolt assembly using the selected resilient member stack to achieve the determined force/deflection characteristics over a deflection of the resilient member stack while said door moves through said predetermined amount and said strike plate remains in contact with said energized electromagnet.

14 . The method of claim 13 wherein said predetermined amount of door movement is between ⅛ inches and ¾ inches.

15 . A strike plate mounting bolt assembly for resiliently mounting a strike plate to a door, wherein an energizable electromagnet is configured to exert a magnetic force against the strike plate when energized, the strike plate mounting bolt assembly comprising:
a) a bolt configured to be received in a first through bore in said door; b) a post connected to said bolt, wherein said post includes a head end and a shaft end opposite said head end, wherein said head end is oriented distal from said inner surface of the strike plate and proximate an outer surface of the strike plate facing said energizable electromagnet when the strike plate is mounted to the door; and c) a resilient member received by said head end of said post and said strike plate.

16 . The strike plate mounting bolt assembly of claim 15 wherein said post is configured to be received in a second through bore in the strike plate.

17 . The strike plate mounting bolt assembly of claim 15 wherein said resilient member is at least one Belleville washer.

18 . The strike plate mounting bolt assembly of claim 15 wherein the strike plate includes a second through bore, wherein said strike plate includes a cavity concentric with said second through bore and disposed on said outer surface, and wherein said resilient member is receivable in said cavity.

19 . The strike plate mounting bolt assembly of claim 17 wherein said resilient member is at least one Belleville washer.

Assignees

• Hanchett Entry Systems Inc

Inventors

• Corwin Jr Larry Gene
• Van Dusen Dan

Classifications

• E05B17/2084

  Means to prevent forced opening by attack, tampering or jimmying (E05B15/1614 takes precedence; for ignition or steering locks B60R25/023) · CPC title

• E05B2015/0465

  Cup- or dished-disc springs · CPC title

• E05B2047/0065

  Saving energy (E05B2047/0053, E05B2047/0074, E05B2047/0077, E05B2047/0079, E05B2047/0081 take precedence) · CPC title

• E05B47/0002

  with electromagnets · CPC title

• E05B2047/0068

  Door closed · CPC title