Switch apparatus responsive to pressure or distortion

• US 4,484,043 A
• Filed: 09/30/1982
• Issued: 11/20/1984
• Est. Priority Date: 09/30/1982
• Status: Expired due to Term

• Current Assignee: JT Posey Company (TIDI Holdings LLC)
• Original Assignee: Bed-Check Corporation (Stanley Black & Decker, Inc.)
• Inventors: Musick, Jeff L., Blaker, Robert D., Blaker, David G. Jr.
• Primary Examiner(s): Scott, J. R.
• Application Number:
  US06/429,047
• Time in Patent Office: 782 Days
• Field of Search: 200/85 R, 200/85 A, 200/86 R, 200/86 A
• US Class Current: 200/85.00R
• CPC Class Codes: A61B 5/1115 Monitoring leaving of a patient support, e.g. a bed or a wheelchair
• CPC Class Codes: A61B 5/6892 Mats
• CPC Class Codes: G08B 21/00 Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for

Abstract

An apparatus for monitoring the presence of a patient in a hospital bed including an elongated, thin, generally rectangular base member of insulating flexible material, such as high-density polyethylene foam, having a generally rectangular cutout opening therein, a rectangular, thin, electrically conductive member affixed to each surface of the base, the base serving to normally maintain the conductive elements spaced apart from each other, a plastic cover cemented to the exterior surface of each of the conductive elements, the edges of the plastic cover being sealed around the full periphery of the device, a cable having two conductors, one conductor being attached to each of the conductive members, the device being generally about 4 inches wide and 34 inches long so that it may be positioned under a patient in a hospital bed, the weight of the patient serving to distort the device so that the conductive members are in contact, providing a closed signal, and the device being sufficiently rigid so that in the absence of a patient the conductive members are not in contact, thereby the absence of a patient from a hospital bed can be indicated when the device is connected to suitable circuitry.

Claims

1. Switch apparatus positionable on a mattress and responsive to distortion by the weight of a patient, comprising:

an elongated, thin, generally rectangular base member of insulating flexible material, the base member being about 31/4 to 5 inches wide and about 25 to 40 inches long, and about 1/16 inch thick, the base member providing a top and bottom surface and having an elongated generally rectangular opening cut out therein, the cut out being about 13/4 to 21/4 inches wide and 231/2 to 381/2 inches long;

a first generally rectangular, thin, electrically conductive member having a first and second surface, the first surface being supported on said top surface of said base member;

a second generally rectangular, thin, electrically conductive member having a first and second surface, the first surface being supported on said bottom surface of said base member, said conductive members being thereby spaced parallel to each other, and of width and length not substantially greater than the width and length of said base member;

a first non-conductive, thin, generally rectangular plastic cover member affixed to said second surface of said first conductive member;

a second non-conductive, thin, generally rectangular plastic cover member affixed to said second surface of said second conductive member; and

a cable having a first and second conductor, the first conductor having engagement with said first conductive member and the second conductor having engagement with said second conductive member, said first and second cover members being of length and width greater than said base member and said cover members providing overlapping edges, the end portion of said cable having said conductor portions engaging said conductive elements being positioned between said cover members, the peripheries of said cover members being sealed, the conductive members being normally supported by said base member in spaced-apart relationship by the memory of said base and said plastic cover members but which members contact each other when the apparatus is subject to bending or twisting distortion.