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US4737707A Expired / Lapsed US ⏱️ 0.0 years remaining

Humidity sensor

Assignee: Panasonic Ecology Systems Co Ltd
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Filing: 1985-06-18
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Granted: 1988-04-12
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Expires: 2005-06-18
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Abstract

Abstract A humidity sensing portion (7) and an electrode (9) of a heating regeneration type humidity sensor provided with a heater (8) are covered by a casing (12) and a holding portion (11). An opening (6) for communication between placing the interior and exterior of the sensor in communication is formed in the casing (12) or the holding portion (11) so that a solid angle, of a vertex at the central portion of the humidity sensing portion (7) or the casing (12) of a polyhedron having a base bounded by the opening is within the range of 1/1000-1/10 radian, and thus, adhesion of harmful substances, especially inorganic harmful substances, onto the humidity sensing portion (7) or the electrode (9) is prevented.

Inventors

  • 👤 Keijiro Mori
  • 👤 Hideaki Yagi
  • 👤 Ichiro Shimano
  • 👤 Tooru Onouchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 09:51
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/0004; G01N33/0009; G01N33/0011; G01N27/00; G01N27/02; G01N27/04; G01N27/12; G01N27/121

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 134 words
A humidity sensor comprising: a humidity sensing portion having an electrode; a heating portion for heating said humidity sensing portion; a holding portion to which the humidity sensing portion and the heating portion are mounted; and a casing for enclosing the humidity sensing portion and the heating portion mounted to the holding portion, at least one of said casing and said holding portion having an opening extending therethrough for placing space interior of the casing in communication with the ambient temperature exterior of the casing, said opening defining the base of a polyhedron having a vortex at the center of the casing, the solid angle of the polyhedron at said vertex being between 1/100 and 1/10 of a radian for inhibiting inorganic substances from entering the interior space of the casing from the atmosphere.
Claim 2
Dependent Claim 134 words
A humidity sensor comprising: a humidity sensing portion having an electrode; a heating portion for heating said humidity sensing portion; a holding portion to which the humidity sensing portion and the heating portion are mounted; and a casing for enclosing the humidity sensing portion and the heating portion mounted to the holding portion, at least one of said casing and said holding portion having an opening extending therethrough for placing space interior of the casing in communication with the ambient temperature exterior of the casing, said opening defining the base of a polyhedron having a vortex at the center of the casing, the solid angle of the polyhedron at said vertex being between 1/100 and 1/10 of a radian for inhibiting inorganic substances from entering the interior space of the casing from the atmosphere.
Claim 3
Dependent Claim 42 words
A humidity sensor as claimed in claim 1, wherein said casing has a double-walled construction comprising a first inner casing through which said opening extends and a second casing extending around said first casing and through which a plurality of through-holes extend.
Claim 4
Dependent Claim 23 words
A humidity sensor as claimed in claim 1 or claim 2, wherein the opening has a width that is less than 1 mm.
Claim 5
Dependent Claim 17 words
A humidity sensor as claimed in claim 1 or claim 2, wherein said opening is a slit.
Claim 6
Dependent Claim 60 words
A humidity sensor as claimed in claim 1 or claim 2, and further comprising at least one other opening extending through the casing, said other opening extending through the casing at a location thereon relative to the location on the casing through which said opening extends which inhibits an air stream originating in the atmosphere from passing through said casing.
Claim 7
Dependent Claim 16 words
A humidity sensor as claimed in claim 2, wherein said second casing comprises a net-like structure.

References Cited (Backward Citations)

US2834201A Cited
US2954445A Cited
US4063897A Cited
JPS56113328A Cited
JPS5747890A Cited
JPS5822944A Cited
JPS59204742A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-04-12 1991-10-12 1992-04-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-04-12 1995-10-12 1996-04-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-04-12 1999-10-12 2000-04-12 $7700.00 Window Closed / Lapsed

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