GB2156955A - Immersion heater - Google Patents

Immersion heater Download PDF

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Publication number
GB2156955A
GB2156955A GB08408933A GB8408933A GB2156955A GB 2156955 A GB2156955 A GB 2156955A GB 08408933 A GB08408933 A GB 08408933A GB 8408933 A GB8408933 A GB 8408933A GB 2156955 A GB2156955 A GB 2156955A
Authority
GB
United Kingdom
Prior art keywords
fluid
heating
heating device
zone
hollow member
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08408933A
Other versions
GB2156955B (en
GB8408933D0 (en
Inventor
Geoffrey Ernest Adams
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to GB08408933A priority Critical patent/GB2156955B/en
Publication of GB8408933D0 publication Critical patent/GB8408933D0/en
Priority to EP85307281A priority patent/EP0221210A1/en
Publication of GB2156955A publication Critical patent/GB2156955A/en
Application granted granted Critical
Publication of GB2156955B publication Critical patent/GB2156955B/en
Expired legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00—Details
    • F24H9/20—Arrangement or mounting of control or safety devices
    • F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
    • F24H9/2014—Arrangement or mounting of control or safety devices for water heaters using electrical energy supply
    • F24H9/2021—Storage heaters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
    • F24H1/18—Water-storage heaters
    • F24H1/20—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
    • F24H1/18—Water-storage heaters
    • F24H1/20—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes
    • F24H1/201—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes using electric energy supply
    • F24H1/202—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes using electric energy supply with resistances
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/10—Control of fluid heaters characterised by the purpose of the control
    • F24H15/174—Supplying heated water with desired temperature or desired range of temperature
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/20—Control of fluid heaters characterised by control inputs
    • F24H15/212—Temperature of the water
    • F24H15/219—Temperature of the water after heating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/20—Control of fluid heaters characterised by control inputs
    • F24H15/212—Temperature of the water
    • F24H15/223—Temperature of the water in the water storage tank
    • F24H15/225—Temperature of the water in the water storage tank at different heights of the tank
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/20—Control of fluid heaters characterised by control inputs
    • F24H15/281—Input from user
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/30—Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/305—Control of valves
    • F24H15/31—Control of valves of valves having only one inlet port and one outlet port, e.g. flow rate regulating valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/30—Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/355—Control of heat-generating means in heaters
    • F24H15/37—Control of heat-generating means in heaters of electric heaters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/40—Control of fluid heaters characterised by the type of controllers
    • F24H15/407—Control of fluid heaters characterised by the type of controllers using electrical switching, e.g. TRIAC
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00—Details
    • F24H9/0005—Details for water heaters
    • F24H9/001—Guiding means
    • F24H9/0015—Guiding means in water channels
    • F24H9/0021—Sleeves surrounding heating elements or heating pipes, e.g. pipes filled with heat transfer fluid, for guiding heated liquid
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/78—Heating arrangements specially adapted for immersion heating
    • H05B3/82—Fixedly-mounted immersion heaters

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid Mechanics (AREA)
  • Heat-Pump Type And Storage Water Heaters (AREA)
  • Steam Or Hot-Water Central Heating Systems (AREA)

Description

1 GB 2 156 955 A 1
SPECIFICATION Heating Device
This invention relates to a heating device for heating fluids.
According to the present invention there is 70 provided a heating device comprising a fluid heating zone defined by a hollow member, a heating element arranged to heat fluid in said zone, and means for releasing at least part of the fluid from said zone when the temperature of the fluid reaches 75 a predetermined value.
Advantageously sensing means is provided for sensing the temperature of fluid in said zone.
Preferably, the fluid heating zone is arranged such that fluid circulates within the zone to improve heat 80 transferfrom the heating element. Advantageously the arrangement is such thatthe circulation is achieved by convection. The heating element may comprise a heating coil, and preferably a fluid passageway extends within the heating coil, to facilitate circulation of the fluid. In one embodiment the heating element may be an electric heating element. In an alternative embodiment the heating element may form a part of a heat exchanger and may be arranged in conjunction with a heat pump.
In one form of the invention, the hollow member comprises a tube, one end of which is sealed, and the other end of which is open and the heating coil is arranged so that the fluid passageway extends axially of the tube.
It is also preferable that the heating element extends to a position adjacent to the open end of the hollow member.
Advantageously, the means for releasing fluid from the hollow member comprises a valve which is 100 controlled by a signal generated by the temperature sensing means, and which is arranged adjacent or at the sealed end of the hollow member.
The temperature sensing means may be a thermostat.
The heating device may be used to heat a tank of fluid such as water and it is desirable that the heating device is disposed in the tank so that the heated fluid released therefrom is at or nearthe top of the tank.
Reference is now made to the accompanying drawings, in which:
Figure 1 is a perspective view of a heating device according to the invention; Figure 2 is a cross-sectional elevation of a tank having a heater according to the invention disposed therein; and Figure 3 is a schematic block diagram of a control circuit for use with a heating device according to the invention.
In Figure 1 a heating device or immersion heater generally designated 1 comprises a hollow tubular member 2 which defines a fluid heating zone has a heating coil 3 disposed therein. The tubular member 2 is provided with an open end 2a and a sealed end 2b. The seated end 2b of the tubular member 2a is provided with a vent 2c which serves the purpose of allowing dissolved gases to leave the tubular member as they are expelled from the fluid during the heating process. The walls of the tubular member 2 are provided with insulation to minimise heat transfer between the water outside the tubular member and water inside the tubular member. This serves to minimise convection currents in the water outside the tubular member. An open-ended tube 4 is arranged within the tubular member 2 so that an annular volume 5 is defined between the outer surface of the tube 4 and the inner surface of the tubular member 2. The heating coil 3 is arranged within this annular volume and is coiled about the outer surface of the tube 4. The tube 4 provides a fluid passageway within the coil 3. One end of the tube 4 is arranged adjacent the open end 2a of the tubular member 2, while the other end of the tube is arranged adjacent the sealed end 2b of the tubular member, so that the fluid can flow through the tube 4. The tube 4 is held in position by means of support members 6. 85 A baffle plate 7 is arranged at the open end 2a of the tubular member 2 and is attached to the tubular member by means of support members 8. Athermostat 9 is arranged on the outside of the tubular member 2, adjacentthe sealed end 2b; the thermostat is provided with a sensor 9a for sensing the temperature of the f luid within the annular volume 5. If the temperature of the f luid within the volume 5 exceeds a predetermined value, then the thermostat 9 generates a signal which causes a valve 10 to be opened, thereby permitting fluid inside the tubular member 2 to leave through the valve. The fluid leaves the member 2 by virtue of its lower density which causes it to rise above the coiderfluid outside the member.
The sealed end 2b of the hollow member 2 is provided with a connector 11 for connecting the heating device 1 to a tank of fluid.
Referring to Figure 2, the heating device 1 is shown disposed in a tank 12 having an inlet opening 13 through which water can enter the tank, and an outlet opening 14 through which water can leave the tank.
The tank 12 is provided with temperature sensors 15 to 19 which can sense the temperature at different depths in the tank. The temperature sensors 15 to 19 are connected to a logic circuit 20 as illustrated in Figure 3.
The operation of the heating device 1 will now be described.
When the power to the heating element is turned on water in the tubular member 2, adjacent the open end 2a begins to warm, and moves upwardly in the direction indicated by arrows A due to the effect of convection. This causes circulation of water upwardly through the annular volume 5 and downwardly through the tube 4. The baffle plate 7 is provided to deflect water leaving the bottom of tube 4 back into the tubular member 2. In this way the volume of water within the tubular member 2 is heated.
When the temperature of the water within the tubular member reaches a predetermined value the thermostat 9 generates a signal which causes the valve 10 to open, whereupon the water within the 2 GB 2 156 955 A 2 tubular member 2 leaves the tubular member through the valve 10 by convection.
As the water leaves the tubular member 2, fresh water is drawn in the tubular member through the open end 2a, thus causing the temperature of the water within the tubular memberto decrease. When the temperature of the water within the tubular member 2 fails below the predetermined value, then the thermostat no longer generates the signal and 1.0 the valve 10 closes.
The same process is then repeated so that a 75 further volume of water is heated within the tubular member 2 and is released into the rest of the tank 12 after it has reached the predetermined temperature.
In this way the heating device 1 increases the depth of hot water measured from the top of the tank 12, every time water is discharged from the tubular member 2 through the valve 10. The amount by which the depth of hot water is increased each time is dependent upon the volume of water which can be held within the tubular member 2.
The way in which the heating device 1 heats the water ensures that there is always a distinct boundary in the tank between the heated water and the cold water. The distance of this boundary from the top of the tank increases as the amount of water 90 heated by the heating device increases.
The temperature sensors 15 to 19 can detect when the level of hot water has reached a particular point, and in combination with the control system shown in Figure 3 makes possible the heating of a predetermined quantity of water in the tank 12.
In Figure 3 the temperature sensors 15 to 19 are connected to a logic circuit 20, which logic circuit is also connected to an operating panel 21. The operating panel 21 allows various functions to be 100 selected by the user: for example the panel could permit the operatorto select various quantities of water to be heated; and to select whether the water is to be heated continuously or once only.
The logic circuit 20 is powered by a low voltage 105 D.C. supply (for example 5v) which in turn is supplied from a voltage supply reduction, rectification and smoothing means 22; a main supply 23 is connected to the voltage reduction, rectification means 22.
The logic circuit 20 is provided with an output to an electronic or electromechanical switching device such as a triac firing circuit 24 which controls a triac 25 to which the mains supply 23 is also connected.
When the triac 25 is activated, the mains supply 23 is connected to the heating device.
The use of the heating device 1 together with the 115 control circuit makes it possible to heat a volume of waterto a desired depth and then to maintain the temperuoure of the water so that water above the desired depth is heated, and water below the desired depth is cold.
The heating device of the present invention has applications other than as an immersion heater. For example, the heating device can be used in fish tanks to maintain the water at the correct temperature. In this application the upper portion of 125 the fish tank could be maintained at a higher temperature than the lower portion, so that fish requiring different temperatures could be kept in the same tank.
It will be appreciated that the heaing device 1 need not be disposed within the tank 12. If desired the heating device 1 can be attached to the outside of the tank 12, and piping can be arranged so that there is fluid communication between the device and the fluid in the tank.

Claims (9)

1. A heating device comprising a fluid heating zone defined by a hollow member, a heating element arranged to heat fluid in said zone, and means for releasing at least part of the fluid from said zone when the temperature of the fluid reaches a predetermined value.
2. A heating device according to Claim 1 in which the fluid heating zone is arranged such thatfluid circulates within the zone to improve heattransfer from the heating element.
3. A heating device according to Claim 1 or 2 in which the heating element comprises a heating coil, and a fluid passageway extends within the heating coil, to facilitate circulation of the fluid.
4. A heating device according to Claim 1, 2 or 3 in which the hollow member comprises a tube, one end of which is sealed, and the other end of which is open, and the heating coil is arranged so thatthe fluid passageway extends axially of the tube.
5. A heating device according to Claim 4 in which the heating element extends to a position adjacent to the open end of the hollow member.
6. A heating device according to any preceding claim in which sensing means is provided for sensing the temperature of fluid in the heating zone. 15
7. A heating device according to claim 6 in which the release means comprises a valve which is controlled by a signal generated by the sensing means, and which is arranged adjacent or at the sealed end of the hollow member. 20
8. A heating device according to claim 6 or 7 in which the sensing means is a thermostat.
9. A heating device substantially as herein described with reference to and as shown in the accompanying drawings.
Printed for Her Majesty's Stationery Office by Courier Press, Leamington Spa. 1011985. Demand No. 8817443. Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.
6. A heating device according to any preceding claim in which the means for releasing fluid from the hollow member comprises a valve which is controlled by a signal generated by the temperature sensing means, and which is arranged adjacent or at the sealed end of the hollow member.
7. A heating device according to any preceding claim in which sensing means is provided for sensing the temperature of fluid in the heating zone.
8. A heating device according to any preceding claim in which the temperature sensing means is to be a thermostat.
9. A heating device according substantially as herein described with reference to and as shown in the accompanying drawings.
New Claims or Amendments to Claimsfiled on 16.4.85. Superseded Claims 1 to 9.
New or Amended Claims:- 1. A heating device comprising a fluid heating zone defined by a hollow member, a heating element arranged to heat fluid in said zone, release means actuatable periodically to release a volume of fluid from the zone, said release means being actuated in response to the fluid in the zone reaching a predetermined temperature.
2. A heating device according to Claim 1 in which the fluid heating zone is arranged such thatfluid circulates within the zone to improve heattransfer from the heating element.
3. A heating device according to Claim 1 or 2 in 3 GB 2 156 955 A 3 which the heating element comprises a heating coil, and a fluid passageway extends within the heating coil, to facilitate circulation of the fluid.
4. A heating device according to Claim 3 in which the hollow member comprises a tube, one end of which is sealed, and the other end of which is open, and the heating coil is arranged so that the fluid passageway extends axially of the tube.
5. A heating device according to Claim 4 in which the heating element extends to a position adjacent to the open end of the hollow member.
GB08408933A 1984-04-06 1984-04-06 Immersion heater Expired GB2156955B (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB08408933A GB2156955B (en) 1984-04-06 1984-04-06 Immersion heater
EP85307281A EP0221210A1 (en) 1984-04-06 1985-10-11 Heating device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB08408933A GB2156955B (en) 1984-04-06 1984-04-06 Immersion heater

Publications (3)

Publication Number Publication Date
GB8408933D0 GB8408933D0 (en) 1984-05-16
GB2156955A true GB2156955A (en) 1985-10-16
GB2156955B GB2156955B (en) 1988-05-05

Family

ID=10559289

Family Applications (1)

Application Number Title Priority Date Filing Date
GB08408933A Expired GB2156955B (en) 1984-04-06 1984-04-06 Immersion heater

Country Status (2)

Country Link
EP (1) EP0221210A1 (en)
GB (1) GB2156955B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0221210A1 (en) * 1984-04-06 1987-05-13 Ernest Geoffrey Adams Heating device
GB2323658A (en) * 1997-03-26 1998-09-30 Kevin Coppard Liquid heater with mixing device
WO2010128497A3 (en) * 2009-05-07 2011-10-13 Moshe Abraham An instantaneous water heating unit for insertion into a hot water storage tank
EP3325867A4 (en) * 2015-07-22 2019-04-03 National Machine Group Hot water tank

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11892198B2 (en) 2017-06-02 2024-02-06 National Machine Company Hot water tank and flow through heating assembly

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1001415A (en) * 1960-08-26 1965-08-18 Eckerfeld Alfred Electrically heated hot water apparatus
GB1278105A (en) * 1969-07-21 1972-06-14 Patterson Kelley Co An electric water heating system
GB2037958A (en) * 1978-11-20 1980-07-16 Hawes R A Heating liquid in a storage tank
GB2079908A (en) * 1980-06-23 1982-01-27 Metal Spinners Ireland Ltd Steam and water boiler

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH289319A (en) * 1953-02-20 1953-03-15 Uhlmann Geb Hot water tank.
FR2050698A5 (en) * 1969-06-20 1971-04-02 Torginol Ind Inc
DE3021444A1 (en) * 1980-06-06 1981-12-24 Jürgen 4500 Osnabrück Vonhoff Heat pump in hot water supply system - uses heat exchanger and water pump in parallel with storage tank for supply control
GB2156955B (en) * 1984-04-06 1988-05-05 Geoffrey Ernest Adams Immersion heater

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1001415A (en) * 1960-08-26 1965-08-18 Eckerfeld Alfred Electrically heated hot water apparatus
GB1278105A (en) * 1969-07-21 1972-06-14 Patterson Kelley Co An electric water heating system
GB2037958A (en) * 1978-11-20 1980-07-16 Hawes R A Heating liquid in a storage tank
GB2079908A (en) * 1980-06-23 1982-01-27 Metal Spinners Ireland Ltd Steam and water boiler

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0221210A1 (en) * 1984-04-06 1987-05-13 Ernest Geoffrey Adams Heating device
GB2323658A (en) * 1997-03-26 1998-09-30 Kevin Coppard Liquid heater with mixing device
WO2010128497A3 (en) * 2009-05-07 2011-10-13 Moshe Abraham An instantaneous water heating unit for insertion into a hot water storage tank
EP3325867A4 (en) * 2015-07-22 2019-04-03 National Machine Group Hot water tank
US10921025B2 (en) 2015-07-22 2021-02-16 National Machine Group Hot water tank

Also Published As

Publication number Publication date
GB2156955B (en) 1988-05-05
GB8408933D0 (en) 1984-05-16
EP0221210A1 (en) 1987-05-13

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