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US4503810A Expired / Lapsed US ⏱️ 0.0 years remaining

Water heater

Assignee: Panasonic Holdings Corp
•
Filing: 1982-05-27
•
Granted: 1985-03-12
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Expires: 2002-05-27
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Abstract

Abstract This invention is a water heater wherein a heat source is located outside a hot water storage tank and high temperature hot water can be distributed between the regions of the hot water storage tank above and below the middle thereof, reducing loss of heat through dissipation and preparing high temperature hot water at uniform temperature in a short time upon depletion of the hot water.

Inventors

  • 👤 Kazuo Fujishita
  • 👤 Hideki Kaneko
  • 👤 Yoshiyuki Ushirokajitani
  • 👤 Tadao Kanno

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 06:15
CPC Classifications
F; F24; F24H; F24H1/00; F24H1/18; F24H1/186; F24H9/00; F24H9/20; F24H9/2007; F24H9/2035

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 355 words
A water heater comprising: a hot water storage tank having a lower region, an upper region, and a lateral wall; a cold water infeed pipe in the lower region of the hot water storage tank; a hot water outfeed pipe in the upper region of the hot water storage tank; a heat source located outside the hot water storage tank; a burner arranged in the heat source; a heat exchanger arranged in the heat source and having an inlet side and an outlet side; an inlet pipe connected between the inlet side of the heat exchanger and the lower region of the hot water storage tank; a first switching valve installed on the outlet side of the heat exchanger; an upper outlet pipe connected to the first switching valve at one end and extending into the upper region of the hot water storage tank at its other end; a spray pipe connected to the other end of the upper outlet pipe, said spray pipe being closed at its front end and having a plurality of small holes spaced along its length and directed downwardly, said spray pipe also having a bar-like or a ring-like cross-section; a lower outlet pipe connected to the first switching valve at one end and extending into the lower region of the hot water storage tank at its other end; and first and second temperature thermistors installed on the lateral wall of the hot water storage tank to turn on and off the burner to control the heating temperature for the hot water storage tank, wherein the first temperature thermistor is disposed in the lower region of the hot water storage tank and the second temperature thermistor is disposed in the upper region of the hot water storage tank, said lower and upper outlet pipes being associated with the first and second temperature thermistors, respectively, wherein the first switching valve is controlled and switched to select either the upper outlet pipe or the lower outlet pipe for high temperature hot water to pass through, depending upon whether either a full load or a small quantity of hot water is needed, respectively.
Claim 2
Dependent Claim 355 words
A water heater comprising: a hot water storage tank having a lower region, an upper region, and a lateral wall; a cold water infeed pipe in the lower region of the hot water storage tank; a hot water outfeed pipe in the upper region of the hot water storage tank; a heat source located outside the hot water storage tank; a burner arranged in the heat source; a heat exchanger arranged in the heat source and having an inlet side and an outlet side; an inlet pipe connected between the inlet side of the heat exchanger and the lower region of the hot water storage tank; a first switching valve installed on the outlet side of the heat exchanger; an upper outlet pipe connected to the first switching valve at one end and extending into the upper region of the hot water storage tank at its other end; a spray pipe connected to the other end of the upper outlet pipe, said spray pipe being closed at its front end and having a plurality of small holes spaced along its length and directed downwardly, said spray pipe also having a bar-like or a ring-like cross-section; a lower outlet pipe connected to the first switching valve at one end and extending into the lower region of the hot water storage tank at its other end; and first and second temperature thermistors installed on the lateral wall of the hot water storage tank to turn on and off the burner to control the heating temperature for the hot water storage tank, wherein the first temperature thermistor is disposed in the lower region of the hot water storage tank and the second temperature thermistor is disposed in the upper region of the hot water storage tank, said lower and upper outlet pipes being associated with the first and second temperature thermistors, respectively, wherein the first switching valve is controlled and switched to select either the upper outlet pipe or the lower outlet pipe for high temperature hot water to pass through, depending upon whether either a full load or a small quantity of hot water is needed, respectively.
Claim 3
Dependent Claim 30 words
A water heater as set forth in claim 1, wherein the heat source is disposed directly on the lateral wall of a lower portion of the hot water storage tank.

References Cited (Backward Citations)

US243680A Cited
US299740A Cited
US591098A Cited
US1050911A Cited
US1421692A Cited
US2814279A Cited
US4027821A Cited
US4155506A Cited
JPH11221A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-03-11 1988-09-10 1989-03-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-03-11 1992-09-10 1993-03-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-03-11 1996-09-10 1997-03-12 $7700.00 Window Closed / Lapsed

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