US3433414A - Heating system - Google Patents
Heating system Download PDFInfo
- Publication number
- US3433414A US3433414A US530947A US3433414DA US3433414A US 3433414 A US3433414 A US 3433414A US 530947 A US530947 A US 530947A US 3433414D A US3433414D A US 3433414DA US 3433414 A US3433414 A US 3433414A
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- US
- United States
- Prior art keywords
- pump
- heating
- boiler
- separate
- rotors
- 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.)
- Expired - Lifetime
Links
- 238000010438 heat treatment Methods 0.000 title description 46
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 16
- 230000001105 regulatory effect Effects 0.000 description 12
- 238000010276 construction Methods 0.000 description 9
- 238000009434 installation Methods 0.000 description 8
- 238000005086 pumping Methods 0.000 description 6
- 239000012530 fluid Substances 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000008236 heating water Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D13/00—Pumping installations or systems
- F04D13/12—Combinations of two or more pumps
- F04D13/14—Combinations of two or more pumps the pumps being all of centrifugal type
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D3/00—Hot-water central heating systems
- F24D3/02—Hot-water central heating systems with forced circulation, e.g. by pumps
Definitions
- This invention relates to a rotary pump for a heating fluid and refers more particularly to a double pump of this type which is particularly suitable for feeding separate heating circuits from a common boiler.
- stage valves are built into each circuit; these valves are operated manually or thermostatically de ending upon heat requirements of the room or rooms heated by the individual circuits.
- stage valves must be operated by electromotors or electromagnets, so that their construction is complicated and expensive.
- the costs of the installation as a whole are substantially increased, particularly since these valves must be added to all other regulating and circulating devices. Furthermore, they often cause operational failures of the installation.
- An object of the present invention is to eliminate the use of these stage valves and to replace them by more reliable and less expensive means.
- a rotary pump for supplying several separate heating circuits from a common boiler, wherein a common pump casing contains separate rotors or groups of rotors with independent drives, which are joined at the suction side to a common suction connection and which at the pressure side are provided with several pressure-transmitting connections for the separate heating circuits.
- a pump of this type as compared to the use of separate pumps for each heating circuit, has firstly the advantage of being less expensive due to its simpler construction; furthermore, by providing a common connection at the suction side the use of one shut-off device is eliminated, since in case of separate pumps two shut-off devices must be provided for each individual pump.
- the installation costs of a double pump are also smaller as compared to those required for two pumps.
- Another important advantage consists in that the larger mass of a double pump dampens particularly effectively the electromagnetic oscillations of the driving motor, which are unavoidable and atent which are transmitted by tubular conduits connected to the pump as so-called body resonance.
- the double pump is provided in each of the two pressure connections with a. flap functioning as forerunner brake and as a check valve; the two pressure connections are also joined by a shut-off device which is located between them.
- a. flap functioning as forerunner brake and as a check valve; the two pressure connections are also joined by a shut-off device which is located between them.
- the pump can be provided with an additional connection to the return flow conduit of the boiler, said connection being associated by regulating devices with the pressure sides of the various rotors or rotor groups.
- a common pipe joint for the return flow of the heating water from the various heating circuits can be mounted in the pump casing and can be connected to the pipe joint providing the return flow of water into the boiler.
- the regulating means are preferably constructed as automatic devices operating dependent upon conditions of the heating medium and air, or the outer temperatures.
- a valve is arranged between conduits providing the return flow of the heating medium and the outflow of the heating medium from the boiler, said valve being preferably operated by means of a thermostat depending upon outer temperature conditions. This valve mixes cold return flow water with the hot water leaving the boiler. Such mixing was found to be particularly useful during transitory periods when the boiler is primarily used for preparing the water to be used for the heating.
- FIGURE 1 is a diagram illustrating the location of a pump of the present invention in a heating installation.
- FIGURE 2 is a diagram showing a somewhat different pump in a heating installation.
- FIGURE 3 is a section through a double heating pump of the present invention.
- FIGURE 4 is a similar section through a somewhat differently constructed pump.
- FIG. 1 shows a double pump 11 having a suction side which is supplied with a heating fluid, such as hot water, from a boiler 10 through a forerunner conduit KV.
- the pressure zone of the pump has two conduits which are connected with two separate circuits HV and HV for heating fluid. These two conduits are interconnected by a pipe connection having a shut-off device 13 which is located between them and behind forerunner brakes 12 which are located in the two conduits at their junction with the pump casing.
- These brakes are to stop all forceful circulation when the pump is switched off; they also serve as relief valves and if one pumping unit gets out of order, they prevent a return flow through that pumping unit, so that after the shut-off device 13 is opened, the two heating circuits can be supplied, if necessary, from a single pumping unit.
- the ends of the heating circuits HR; and HR, are connected to a conduit KR returning the fluid to the boiler 10.
- the pump of the present invention is provided with two additional pipe joints KR and HR leading to the bottom of the boiler and to the ends of the heating circuits, respectively. Furthermore, in accordance with this construction the conduit KV is connected with the conduit HR for the return fiow through a valve 14 which is actuated by a thermostat 15.
- FIGS. 3 and 4 show diagrammatically actual constructions of the double pumps.
- the pump of FIG. 3 has two pressure zones or chambers 21 which may communicate with a central collecting space through regulating valves 19.
- the valves 19 have an open cross-sectional area in the closed portion, so that they cannot completely shut off flow. They may be operated automatically by means (not shown) depending upon conditions of the heating medium, air or outer temperature.
- Each of the rotors actuates a separate circuit for the circulation of the heating medium, as indicated by the indicia HV and HV Forerunner brakes 12 are located in these circuits; they consist of spring-engaged relief flaps or valves.
- the relief flaps 12 are pressed by their springs in the direction opposed to the flow of the heating medium through the respective pressure zones.
- FIG. 4 shows a collecting chamber 20 receiving the conduit HR of the heating circuits and the conduit KR for the boiler return flow.
- the arrangement indicated in FIG. 4 is that the openings of these conduits which lead into the collecting chamber 20, are angularly shifted relatively to each other, one opening being located in front of the plane of FIG. 4, while the other opening is located behind the plane of FIG. 4. They may be shifted to the extent of 90 relatively to each other.
- a single pump casing a plurality of pumping rotors in said casing, the number of said rotors being equal to that of said heating circuits, a separate drive for each of said rotors, the interior of said casing having a suction zone common to all rotors, a pipe joint connecting said suction zone with said boiler, said rotors forming separate pressure zones within said casing, separate pipe joints connecting each pressure zone with the inlet of a separate heating circuit, a separate relief flap in each pressure zone, a spring pressing said flap in the direction opposed to the flow of the heating medium through that pressure zone, a pipe connection interconnecting the pressure zones behind said flaps in relation to the direction of flow and means shutting off said pipe connection.
- a single pump casing a plurality of pumping rotors in said casing, the number of said rotors being equal to that of said heating circuits, a separate drive for each of said rotors, the interior of said casing having a suction zone common to all rotors, a pipe joint connecting said suction zone with said boiler, said rotors forming separate pressure zones within said casing, separate pipe joints connecting each pressure zone with the inlet of a separate heating circuit, means connecting said pump casing with outlets of said heating circuits, a valve connected with the first-mentioned pipe joint and said means, and a thermostat operating said valve.
- a single pump casing In combination with a single boiler and a plurality of separate heating circuits, a single pump casing, a plurality of pumping rotors in said casing, the number of said rotors being equal to that of said heating circuits, a separate drive for each of said rotors, the interior of said casing having a suction zone common to all rotors, a pipe joint connecting said suction zone with said boiler, said rotors forming separate pressure zones within said casing, separate pipe joints connecting each pressure zone with the inlet of a separate heating circuit, means connecting said pump casing with outlets of said heating circuits, means connecting said pump casing with the bottom of said boiler, said pump casing having a collecting chamber communicating with both said means, and regulating valves located between collecting chamber and said pressure zones.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
- Steam Or Hot-Water Central Heating Systems (AREA)
Description
March 18, 1969 G. BOES HEATING SYSTEM Sheet Filed March 1, 1966 HVH Fig.1
r .m M. n e
e T mo B [W 2 G Q mm P March 18; 1969 5. BOES HEATING SYSTEM Sheet L of 2 Filed March 1, 1966 Inventor: G: B o e s dZMhv nite States 3,433,414 HEATING SYSTEM Gunther Boes, Munstermannskamp 16, Luneburg, Germany Filed Mar. 1, 1966, Ser. No. 530,947 Claims priority, application Germany, Sept. 17, 1965,
L 51,658 US. Cl. 237-8 Int. Cl. F24d 3/02, 3/00, 1/00 4 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a rotary pump for a heating fluid and refers more particularly to a double pump of this type which is particularly suitable for feeding separate heating circuits from a common boiler.
In many heating installations, for example, those of one family homes, the heating requirements of the individual rooms greatly differ one from the other due to their different locations with respect to reception of heat from the sun and also due to the different extent of use of the various rooms; economically it is most impractical to employ a single heating circuit for these different heat requirements. Therefore, in order to improve the efiiciency of the heat installation as a whole, a single boiler has been provided with several separate heating circuits.
In prior art installations of this type wherein several separate circuits are used, so-called stage valves are built into each circuit; these valves are operated manually or thermostatically de ending upon heat requirements of the room or rooms heated by the individual circuits. These valves must be operated by electromotors or electromagnets, so that their construction is complicated and expensive. Thus the costs of the installation as a whole are substantially increased, particularly since these valves must be added to all other regulating and circulating devices. Furthermore, they often cause operational failures of the installation.
An object of the present invention is to eliminate the use of these stage valves and to replace them by more reliable and less expensive means.
Other objects of the present invention will become apparent in the course of the following specification.
In the accomplishment of the objectives of the present invention it was found desirable to provide a rotary pump for supplying several separate heating circuits from a common boiler, wherein a common pump casing contains separate rotors or groups of rotors with independent drives, which are joined at the suction side to a common suction connection and which at the pressure side are provided with several pressure-transmitting connections for the separate heating circuits.
A pump of this type, as compared to the use of separate pumps for each heating circuit, has firstly the advantage of being less expensive due to its simpler construction; furthermore, by providing a common connection at the suction side the use of one shut-off device is eliminated, since in case of separate pumps two shut-off devices must be provided for each individual pump. The installation costs of a double pump are also smaller as compared to those required for two pumps. Another important advantage consists in that the larger mass of a double pump dampens particularly effectively the electromagnetic oscillations of the driving motor, which are unavoidable and atent which are transmitted by tubular conduits connected to the pump as so-called body resonance.
In a final structural embodiment of the present invention, the double pump is provided in each of the two pressure connections with a. flap functioning as forerunner brake and as a check valve; the two pressure connections are also joined by a shut-off device which is located between them. A construction of this type makes it possible to maintain a satisfactory supply to both heating circuits even in the case of a breakdown of one pump unit, since then the shut-off device is opened and the still operating pump unit can be set to a correspondingly greater output by regulating means which Will be described hereinafter.
According to a further embodiment of the invention the pump can be provided with an additional connection to the return flow conduit of the boiler, said connection being associated by regulating devices with the pressure sides of the various rotors or rotor groups. Furthermore, a common pipe joint for the return flow of the heating water from the various heating circuits can be mounted in the pump casing and can be connected to the pipe joint providing the return flow of water into the boiler. According to this construction the water flowing back after the heating does not reach the boiler immediately, so that it can not cause corrosion therein, which can happen if the water is cooled to a great extent; on the contrary, this cooled water is mixed within the pump with warm water by the regulating means, so that there can never be a drop below the dew point at the inlet to the boiler.
It was found advantageous to provide the regulating means in their closing position with an open minimal cross sectional area for the flow between the pressure sides of the rotors or rotor groups and the pipe joint for the return flow conduit to the boiler. Then the cold return water is always mixed with some hot water and this mixing can not be prevented by an erroneous closing of the regulating means. The regulating means are preferably constructed as automatic devices operating dependent upon conditions of the heating medium and air, or the outer temperatures. According to a preferred embodiment of the invention a valve is arranged between conduits providing the return flow of the heating medium and the outflow of the heating medium from the boiler, said valve being preferably operated by means of a thermostat depending upon outer temperature conditions. This valve mixes cold return flow water with the hot water leaving the boiler. Such mixing was found to be particularly useful during transitory periods when the boiler is primarily used for preparing the water to be used for the heating.
The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings showing by way of example only, preferred embodiments of the inventive idea.
In the drawings:
FIGURE 1 is a diagram illustrating the location of a pump of the present invention in a heating installation.
FIGURE 2 is a diagram showing a somewhat different pump in a heating installation.
FIGURE 3 is a section through a double heating pump of the present invention.
FIGURE 4 is a similar section through a somewhat differently constructed pump.
Similar parts are designated by the same numerals or letters in the various figures.
FIG. 1 shows a double pump 11 having a suction side which is supplied with a heating fluid, such as hot water, from a boiler 10 through a forerunner conduit KV. The pressure zone of the pump has two conduits which are connected with two separate circuits HV and HV for heating fluid. These two conduits are interconnected by a pipe connection having a shut-off device 13 which is located between them and behind forerunner brakes 12 which are located in the two conduits at their junction with the pump casing. The purpose of these brakes is to stop all forceful circulation when the pump is switched off; they also serve as relief valves and if one pumping unit gets out of order, they prevent a return flow through that pumping unit, so that after the shut-off device 13 is opened, the two heating circuits can be supplied, if necessary, from a single pumping unit.
The ends of the heating circuits HR; and HR, are connected to a conduit KR returning the fluid to the boiler 10.
In the construction of FIG. 2 the pump of the present invention is provided with two additional pipe joints KR and HR leading to the bottom of the boiler and to the ends of the heating circuits, respectively. Furthermore, in accordance with this construction the conduit KV is connected with the conduit HR for the return fiow through a valve 14 which is actuated by a thermostat 15.
FIGS. 3 and 4 show diagrammatically actual constructions of the double pumps. The pump of FIG. 3 has two pressure zones or chambers 21 which may communicate with a central collecting space through regulating valves 19. The valves 19 have an open cross-sectional area in the closed portion, so that they cannot completely shut off flow. They may be operated automatically by means (not shown) depending upon conditions of the heating medium, air or outer temperature. There are two rotors 16 driven by motor shafts 17 extending through projecting portions 18 of the casing. Separate drives are provided for the rotors and these drives may be operated from separate room thermostats (not shown). Each of the rotors actuates a separate circuit for the circulation of the heating medium, as indicated by the indicia HV and HV Forerunner brakes 12 are located in these circuits; they consist of spring-engaged relief flaps or valves. The relief flaps 12 are pressed by their springs in the direction opposed to the flow of the heating medium through the respective pressure zones.
The construction of the pump shown in FIG. 4 is substantially the same as that of FIG. 3. However, FIG. 4 shows a collecting chamber 20 receiving the conduit HR of the heating circuits and the conduit KR for the boiler return flow. The arrangement indicated in FIG. 4 is that the openings of these conduits which lead into the collecting chamber 20, are angularly shifted relatively to each other, one opening being located in front of the plane of FIG. 4, while the other opening is located behind the plane of FIG. 4. They may be shifted to the extent of 90 relatively to each other.
Operation Liquid rising from the boiler 10 reaches the pump through the inlet KV and enters into the suction zone of the pump. Rotors 16 transmit the heating liquid into the circuits the inlets of which are designated as HV and HV The flow of the liquid within the pump is designated by arrows. According to the embodiment of FIG. 4 liquid returning from the heating circuits flows through the conduit HR back into the collecting chamber 20 and leaves the pump casing through the conduit KR, returning to the bottom of the boiler. The collecting chamber 20 also receives warm water from the pressure section of the pump, so that inflowing warm water is mixed with the outfiowing cooled water. Regulating valves 19 are used to regulate the amount of the hot water which is to be admixed to the cooled water. In the constructions of FIGS. 3 and 4 the left-hand regulating valve is shown as being completely open, while the right-hand valve is shown as being closed.
It is apparent that the above-described examples have been given solely by way of illustration and not by way of limitation and that they are subject to many variations and modifications within the scope of the present invention. All such variations and modifications are to be included within the scope of the present invention.
What is claimed is:
1. In combination with a single boiler and a plurality of separate heating circuits, a single pump casing, a plurality of pumping rotors in said casing, the number of said rotors being equal to that of said heating circuits, a separate drive for each of said rotors, the interior of said casing having a suction zone common to all rotors, a pipe joint connecting said suction zone with said boiler, said rotors forming separate pressure zones within said casing, separate pipe joints connecting each pressure zone with the inlet of a separate heating circuit, a separate relief flap in each pressure zone, a spring pressing said flap in the direction opposed to the flow of the heating medium through that pressure zone, a pipe connection interconnecting the pressure zones behind said flaps in relation to the direction of flow and means shutting off said pipe connection.
2. In combination with a single boiler and a plurality of separate heating circuits, a single pump casing, a plurality of pumping rotors in said casing, the number of said rotors being equal to that of said heating circuits, a separate drive for each of said rotors, the interior of said casing having a suction zone common to all rotors, a pipe joint connecting said suction zone with said boiler, said rotors forming separate pressure zones within said casing, separate pipe joints connecting each pressure zone with the inlet of a separate heating circuit, means connecting said pump casing with outlets of said heating circuits, a valve connected with the first-mentioned pipe joint and said means, and a thermostat operating said valve.
3. In combination with a single boiler and a plurality of separate heating circuits, a single pump casing, a plurality of pumping rotors in said casing, the number of said rotors being equal to that of said heating circuits, a separate drive for each of said rotors, the interior of said casing having a suction zone common to all rotors, a pipe joint connecting said suction zone with said boiler, said rotors forming separate pressure zones within said casing, separate pipe joints connecting each pressure zone with the inlet of a separate heating circuit, means connecting said pump casing with outlets of said heating circuits, means connecting said pump casing with the bottom of said boiler, said pump casing having a collecting chamber communicating with both said means, and regulating valves located between collecting chamber and said pressure zones.
4. A pump in accordance with claim 3, wherein said regulating valves have an open cross-sectional area in the closed position.
References Cited UNITED STATES PATENTS 2,153,382 4/1939 Martin. 2,211,573 8/1940 McGrath 2378 2,295,149 9/ 1942 Adams et a1. 2,490,932 12/ 1949 Thuney 237-8 2,557,369 6/1951 Broderick 237-63 X 2,810,345 10/1957 Englesson 103-107 3,257,076 6/1966 Laing et al. 237-8 FOREIGN PATENTS 1,119,485 12/1961 Germany.
EDWARD J. MICHAEL, Primary Examiner.
US. Cl. X.R. 103-407; 237-63
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEL0051658 | 1965-09-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3433414A true US3433414A (en) | 1969-03-18 |
Family
ID=7274194
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US530947A Expired - Lifetime US3433414A (en) | 1965-09-17 | 1966-03-01 | Heating system |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3433414A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7048200B2 (en) | 2003-06-27 | 2006-05-23 | Taco, Inc. | Integrated injection-pumping fixture for transferring heat between higher and lower-temperature loops in a hydronic heating system |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2153382A (en) * | 1935-06-22 | 1939-04-04 | Gen Electric | Zone heating system |
| US2211573A (en) * | 1938-01-13 | 1940-08-13 | Honeywell Regulator Co | Heating system |
| US2295149A (en) * | 1939-08-10 | 1942-09-08 | Honeywell Regulator Co | Control apparatus |
| US2490932A (en) * | 1945-05-31 | 1949-12-13 | Honeywell Regulator Co | Control apparatus |
| US2557369A (en) * | 1948-02-21 | 1951-06-19 | Broderick Ellen | Heating system |
| US2810345A (en) * | 1953-02-12 | 1957-10-22 | Flygts Pumpar Ab | Pump device |
| DE1119485B (en) * | 1959-06-06 | 1961-12-14 | Thermo Appbau G M B H | Water circulation pump, preferably for collective heating systems |
| US3257076A (en) * | 1959-11-03 | 1966-06-21 | Laing | Heating system |
-
1966
- 1966-03-01 US US530947A patent/US3433414A/en not_active Expired - Lifetime
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2153382A (en) * | 1935-06-22 | 1939-04-04 | Gen Electric | Zone heating system |
| US2211573A (en) * | 1938-01-13 | 1940-08-13 | Honeywell Regulator Co | Heating system |
| US2295149A (en) * | 1939-08-10 | 1942-09-08 | Honeywell Regulator Co | Control apparatus |
| US2490932A (en) * | 1945-05-31 | 1949-12-13 | Honeywell Regulator Co | Control apparatus |
| US2557369A (en) * | 1948-02-21 | 1951-06-19 | Broderick Ellen | Heating system |
| US2810345A (en) * | 1953-02-12 | 1957-10-22 | Flygts Pumpar Ab | Pump device |
| DE1119485B (en) * | 1959-06-06 | 1961-12-14 | Thermo Appbau G M B H | Water circulation pump, preferably for collective heating systems |
| US3257076A (en) * | 1959-11-03 | 1966-06-21 | Laing | Heating system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7048200B2 (en) | 2003-06-27 | 2006-05-23 | Taco, Inc. | Integrated injection-pumping fixture for transferring heat between higher and lower-temperature loops in a hydronic heating system |
| US20060196959A1 (en) * | 2003-06-27 | 2006-09-07 | Taco, Inc. | Integrated injection-pumping fixture for transferring heat between higher and lower-temperature loops in a hydronic heating system |
Also Published As
| Publication number | Publication date |
|---|---|
| DE1579954A1 (en) | 1970-09-24 |
| DE1579954B2 (en) | 1975-10-02 |
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