Liquid sensor and body fluid leak sensing device comprising the same

• US 6,433,695 B1
• Filed: 08/04/2000
• Issued: 08/13/2002
• Est. Priority Date: 02/04/1998
• Status: Expired due to Fees

• Current Assignee: Nipro Corporation
• Original Assignee: Nipro Corporation, Sanwa Newtech Company Limited
• Inventors: Todoroki, Hiroshi, Kai, Kazuo, Fujino, Shoichiro, Ando, Ritsuo
• Primary Examiner(s): MULLEN, THOMAS J
• Application Number:
  US09/601,622
• Time in Patent Office: 739 Days
• Field of Search: 340/573.5, 340/604, 340/539, 73/73, 200/61.04, 200/61.05, 600/372, 600/382
• US Class Current: 340/604
• CPC Class Codes: A61B 2562/02 Details of sensors specially adapted for in-vivo measurements
• CPC Class Codes: A61B 5/202 Assessing bladder functions, e.g. incontinence assessment
• CPC Class Codes: A61B 5/4261 Evaluating exocrine secretion production A61B3/101 takes precedence
• CPC Class Codes: A61F 13/42 with wetness indicator or alarm
• CPC Class Codes: A61F 5/48 Devices for preventing wetting or pollution of the bed
• CPC Class Codes: G01N 27/121 for determining moisture content, e.g. humidity, of the fluid moisture content of the tested material G01N27/048

Abstract

A body fluid leak sensing device adapted for correctly informing only a caretaker of a leak of body fluid. The sensing device is miniaturized so as to properly operate in any worn state. A liquid sensor applicable to the body fluid leak sensing device is disposable and highly sensitive to even a small amount of body fluid. A sensor (1) comprises a water absorber (11) formed of a porous material with a high electrical resistance and an insulating coating film (14) on which the ends (12a, 13a) of the electrodes (12, 13) are secured at its sides and spaced from each other in such a way that one end (11a) of the water absorber (11) is exposed. There are provided means for detecting leak of body fluid by measuring the resistance of the sensor (1) and means for informing according to the detection.

Claims

1. A liquid sensing sensor, comprising a water absorber made of a porous material having high electric resistance which is provided on a head of the sensor, at least two electrodes having respective tips arranged separate from each other through the water absorber but fixed to the water absorber respectively, and a coating means for covering the water absorber and the tips, wherein the porous material is porous glass calcined from volcanic fallen ash or sand as a main raw material.

2. The liquid sensing sensor as claimed in claim 1, characterized in that the coating means covers the tips of electrodes and coats the water absorber so that a portion of the water absorber is exposed.

3. The liquid sensing sensor as claimed in claim 1, characterized in that the porous material has a pore diameter of 0.1 to 50.0 μ

m.

4. The liquid sensing sensor as claimed in claim 3, characterized in that the porous material has a pore diameter of 6 to 50.0 μ

m.