US5852239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flow sensor having an intermediate heater between two temperature-sensing heating portions
Assignee: Ricoh Co Ltd
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Filing: 1997-06-12
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Granted: 1998-12-22
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Expires: 2017-06-12
Abstract
Abstract A flow sensor includes a first heating portion, provided at a first position in a flow of a fluid, which heats the fluid and outputs a voltage in response to a temperature of the first position. A second heating portion, provided at a second, downstream position in the flow of the fluid, heats the fluid and outputs a voltage in response to a temperature of the second position, the first position and the second position being spaced from each other in a direction parallel to the flow of the fluid. An intermediate heater, provided between the first heating portion and the second heating portion, heats the fluid at an intermediate position between the first position and the second position.
Inventors
- 👤 Yukito Sato
- 👤 Takayuki Yamaguchi
- 👤 Hiroyoshi Shoji
- 👤 Junichi Azumi
- 👤 Morimasa Kaminishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:26
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/68; G01F1/684; G01F1/6845
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
132 words
A flow sensor for sensing a flow rate of a fluid, comprising: a first heating portion, provided at a first position in a flow of the fluid, for heating the fluid and for outputting a voltage in response to a temperature of the first position; a second heating portion, provided at a second, downstream position in the flow of the fluid, for heating the fluid and for outputting a voltage in response to a temperature of the second position, the first position and the second position being spaced from each other in a direction parallel to the flow of the fluid; and an intermediate heater, provided between the first heating portion and the second heating portion, for heating the fluid at an intermediate position between the first position and the second position.
Claim 2
Dependent Claim
132 words
A flow sensor for sensing a flow rate of a fluid, comprising: a first heating portion, provided at a first position in a flow of the fluid, for heating the fluid and for outputting a voltage in response to a temperature of the first position; a second heating portion, provided at a second, downstream position in the flow of the fluid, for heating the fluid and for outputting a voltage in response to a temperature of the second position, the first position and the second position being spaced from each other in a direction parallel to the flow of the fluid; and an intermediate heater, provided between the first heating portion and the second heating portion, for heating the fluid at an intermediate position between the first position and the second position.
Claim 3
Dependent Claim
67 words
The flow sensor according to claim 1, wherein said flow sensor senses a flow rate of the fluid based on a difference between the voltages output by the first heating portion and the second heating portion while the fluid at the first position, at the intermediate position and at the second position is heated by the first heating portion, the intermediate heater and the second heating portion.
Claim 4
Dependent Claim
25 words
The flow sensor according to claim 1, wherein each of the first heating portion and the second heating portion comprises a thin-film thermistor heating element.
Claim 5
Dependent Claim
29 words
The flow sensor according to claim 1, wherein each of the first heating portion and the second heating portion comprises a thin-film heating element and a thin-film temperature-sensing element.
Claim 6
Dependent Claim
34 words
The flow sensor according to claim 1, further comprising a slit provided between the first heating portion and the intermediate heater and a slit provided between the intermediate heater and the second heating portion.
Claim 7
Dependent Claim
89 words
The flow sensor according to claim 1, wherein the flow sensor includes a substrate with a cavity therein, and a supporting portion, the supporting portion being formed on the substrate in the shape of a bridge diagonally extending over the cavity of the substrate, and wherein the first heating portion, the intermediate heater and the second heating portion are formed on a surface of the supporting portion, the supporting portion being arranged such that the supporting portion extends in a horizontal direction perpendicular to the flow of the fluid.
Claim 8
Dependent Claim
89 words
The flow sensor according to claim 1, wherein the flow sensor includes a substrate with a cavity therein, and a supporting portion, the supporting portion being formed on the substrate in the shape of a bridge diagonally extending over the cavity of the substrate, and wherein the first heating portion, the intermediate heater and the second heating portion are formed on a surface of the supporting portion, the supporting portion being arranged such that the supporting portion extends in a horizontal direction parallel to the flow of the fluid.
Claim 9
Dependent Claim
63 words
The flow sensor according to claim 1, wherein the flow sensor includes a substrate with a cavity therein, and a supporting portion, the supporting portion being formed integrally with a surface of the substrate as a diaphragm overlaying the cavity, and wherein the first heating portion, the intermediate heater and the second heating portion are arranged on a surface of the supporting portion.
References Cited (Backward Citations)
US4651564A
Cited
JPH02193019A
Cited
JPH02259527A
Cited
JPH0352028A
Cited
US5291781A
Cited
JPH0643906A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-12-21 | 2002-06-22 | 2002-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-12-21 | 2006-06-22 | 2006-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-12-21 | 2010-06-22 | 2010-12-22 | $7700.00 | Window Closed / Lapsed |