JPS61101742A - Engine heat pump device - Google Patents

Abstract

PURPOSE:To utilize high-temperature heat from the initial stage of startup by switching the first brine circulation passage by a three-way valve when the brine temperature in a baffer tank is low to cause the brine to bypass the baffer tank and flow into the second brine circulation passage on the utilization side. CONSTITUTION:When the temperature at a brine temperature sensor 44 disposed in a baffer tank 31 is lower than the set temperature in the initial stage of a system startup, three-way valves 40, 41 are switched to cause the brine in the first brine circulating passage 34 to flow through a water-cooled condenser 24, a coolant heat exchanger 27 and an exhaust gas heat exchanger 28 whereby the brine is heated. It then flows from the three-way valve 41 through a bypass pipe 43 to a pump 36 in the second brine circulating passage and a utilization side heat exchanger 37, and further on to a bypass pipe 42 and the three-way valve 40 to again return to the first brine circulating passage 34. Therefore, since the brine circulates with the buffer tank 31 of large heat capacity bypassed, the temperature rises in a short period of time even when the brine temperature in the tank 31 is low, and high-temperature heat can be utilized from the initial stage of startup owing to the heat exchanger 37.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an engine-driven heat pump device having a buffer tank, and particularly relates to an engine heat pump device that can utilize high-temperature heat from the initial stage of startup. .

[Prior Art] In general, an engine-driven heat pump device can recover waste heat from engine exhaust gas or heat from water cooling using an exhaust gas heat exchanger or a water cooling heat exchanger. It is more efficient in energy use than other types of water heaters, and is used in various types of water heaters. In this engine heat pump device, for example, as shown in FIG. 2, a compressor 2 is driven by an engine 1,
A circulation path is formed in which the refrigerant passes through the compressor 2 → water-cooled condenser 3 → expansion valve 4 → evaporator 5, and returns to the compression va2 again. or,
A cooling water heat exchanger 6 and an exhaust gas heat exchanger 7 are provided in the cooling water circulation path and the exhaust gas path of the engine 1, and a pump 8 moves the water cooling condenser 3 → cooling water heat exchanger 6 → exhaust gas A prine circulation path is formed from the heat exchanger 7 to the pump 8 via the buffer 7 and the tank 9. On the usage side, a circulation path is formed from the buffer tank 9 → pump 10 → usage side heat exchanger 11 and returning to the buffer tank 9. Further, a backup boiler 13 is connected to the circulation path between the pump 10 and the user-side heat exchanger 11 via a three-way switching valve 12, and operates simultaneously with the heat pump at low temperatures. . This user-side heat exchanger 11 is connected to a heat supply facility (not shown) or the like so as to circulate. The exhaust gas that has passed through the exhaust gas heat exchanger 7 is discharged to the outside through a muffler 14.

[Problems to be Solved by the Invention] However, in such a conventional engine heat pump device, when the pline temperature in the buffer tank 9 is low at the beginning of startup, etc., the heat load is large and the pline temperature rises. It takes a relatively long time to
There was a problem in that high-temperature heat could not be extracted immediately from the For this reason, the backup boiler 13 had to be operated at the same time as the heat pump, and the heat had to be recovered into the prine and supplied to the heat exchanger 11 on the user side.

Although Japanese Patent Laid-Open Publication No. 57-95564 discloses a conventional technique related to an air-conditioning/heating/hot-water supply system, it does not solve the above-mentioned problems.

The present invention was made in view of these conventional problems, and an object of the present invention is to provide an engine heat pump device having a buffer tank that can utilize high-temperature heat from the initial stage of startup. It is said that

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a refrigerant circuit in which a compressor is driven by an engine to circulate refrigerant, and a water-cooled condenser and a buffer in the refrigerant circuit. In the engine heat pump device, the engine heat pump device includes a first pline circulation path that circulates through a tank, etc., and a second pline circulation path that sucks pline from the buffer tank, flows through the user side heat exchanger, and returns to the buffer tank again. A bypass pipeline provided with a three-way switching valve in each of the return side and discharge side pipelines of the buffer tank of the prine circulation path, and connected to the suction side and return side pipelines of the second prine circulation path, respectively, via the three-way switching valve. is provided, and when the pline temperature in the buffer tank is low, the three-way switching valve is switched to allow the pline to flow into the bypass pipe.

[Operation] Next, the operation will be explained. In this invention, when the prine temperature in the buffer tank is low, the three-way switching valve is switched to bypass the buffer tank and the prine flows from the first pline circulation path to the second pline circulation path and returns to the first pline circulation path again. As a result, the total heat capacity of the circulating plines becomes small, and the temperature of the plines rises in a short time due to heat exchange with a water-cooled condenser. Therefore, heat can be used immediately after startup. Further, when the prine temperature in the buffer tank becomes higher than a predetermined temperature, the three-way switching valve is switched and normal operation is performed by independently circulating the first and second prine circulation paths.

[Examples] Examples according to the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a system diagram of an engine heat pump device according to an embodiment of the present invention.

In this figure, reference numeral 21 is an engine, and 22 is a compression chamber driven by the engine 21. And, the refrigerant circulation path 23 of this engine heat pump device is compressed! fi
The air is circulated from the high pressure side of the compressor 22 through the water-cooled condenser 24 → expansion valve 25 → evaporator 26 to the low pressure side of the compressor 22. A cooling water heat exchanger 2 is provided in the cooling water circulation path of the engine 21 to recover heat generated by water cooling of the engine 21.
7 is connected. Further, an exhaust gas heat exchanger 28 is provided in the exhaust gas path of the engine 21. Then, the exhaust gas is transferred from this exhaust gas heat exchanger 28 to the muffler.
The lJF is output to the outside through 29. A pline outlet side conduit 32 connected to a buffer tank 31 via a pump 30 is provided on the pline inlet side of the water-cooled condenser 24 . Moreover, the exhaust gas heat exchanger 2
A pline return side conduit 33 connected to a buffer tank 31 is provided on the pline outlet side of No. 8. The first pline circulation path 34 during normal operation is as follows: buffer tank 31 → pline outlet side pipe line 32 → pump 30 → water-cooled condenser 24 → cooling water heat exchanger 27 → exhaust gas heat exchanger 2
8 → forms a circulation path that returns to the buffer tank 31 again via the pline return side pipe 33.

Also, on the user side, from the suction side pipe 35 provided above the bulk tank 31 to the pump 36 → the user side heat exchanger 37
→A second prine circulation path 39 is formed which returns to the lower part of the buffer tank 30 via the return side pipe 38. The user-side heat exchanger 37 is connected to a hot water supply facility (not shown) so as to circulate therein. Note that the pump 30 in the first line circulation path 34 is the same as the pump 3 in the 27th line circulation path 39.
A capacitor with a larger capacity than 6 is used.

On the other hand, a three-way switching valve 40.4'l is provided in the middle of the pline return side conduit 32 and the pline outlet side conduit 33 of the first pline circulation path 34, respectively. and,
The three-way switching valves 40 and 41 each have a bypass line 4.
One end of 2.43 is connected, and the other end is connected to the return side conduit 38 and the suction side conduit 35 of the second pline circulation path 39, respectively. Further, the buffer tank 30 is provided with a Pline temperature sensor 44.

In such a configuration, the engine 21 starts and compresses the second image.
2 is driven to circulate the refrigerant, and the pumps 30 and 36 circulate the plines.

When the prine temperature detector 44 provided in the buffer tank 30 is below a predetermined set temperature at the initial stage of starting up the apparatus, the three-way switching valves 40 and 41 are switched. By operating in this state, the plines of the first pline circulation path 34 are connected to the water-cooled condenser 24, the cooling water heat exchanger 27. After flowing through the exhaust gas heat exchanger 28 and being heated, the three-way switching valve 41
The bypass □ flows through the pass pipe 43, flows through the bong 736 of the second line circulation path, the user side heat exchanger 37, and then flows through the bypass pipe 42. It returns to the first pline circulation path 34 again via the three-way switching valve 40. Therefore, since the prine circulates bypassing the buffer tank 31 which has a large heat capacity, the temperature of the prine in the buffer tank 31 is increased in a short time even when the temperature is low, and high-temperature heat is utilized from the initial stage of startup by the user-side heat exchanger 37. can do. In addition, in this embodiment, the capacity of the pump 3o of the first prine circulation path 34 is the 27th
Since the capacity of the line circulation path 39 is larger than that of the pump 36, an amount of pline equal to the difference in capacity is circulated, and the temperature of the pline in the buffer tank 31 can be gradually raised. or,
When the pline temperature in the buffer tank 31 becomes higher than a predetermined set temperature, the three-way switching valve 40.41 is switched to circulate the first and second pline circulation paths 34.39 independently to perform normal operation. be exposed.

In the above embodiment, the three-way switching valves 40 and 41 are arranged so that when the prine temperature in the buffer tank 31 is low, the prine bypasses the buffer tank 31 and flows through the first pline circulation path 34 and the second pline circulation path 39. It is sufficient if the temperature can be switched, or it may be automatically switched based on the temperature detected by the temperature detector 44. Furthermore, the systems of the first and second prine circulation paths 34, 39 are not limited to the embodiments, and can be any system.

[Effects of the Invention] As explained above, according to the present invention, in an engine heat pump device having a buffer tank, when the pline temperature in the buffer tank is low, the first pline circulation path is switched by a three-way switching valve, Since the buffer tank is bypassed and the pline flows through the second pline circulation path on the user side, there is an effect that high temperature heat can be utilized from the initial stage of startup. Furthermore, by changing the pump capacity of the first and second plines @ ring path, there is an effect that the plines in the buffer tank can also be gradually FNiMed.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an engine heat pump device according to an embodiment of the present invention, and FIG. 2 is a system diagram of eight engine heat pumps according to a conventional example. 21...Engine 22...Compressor 23...
- Refrigerant circulation path 24... Water-cooled condenser 25... Expansion valve 26... Evaporator 30. 36... Pump 31... Buffer tank 32... Outlet side pipe line 33... Return side Pipe line 34...First pline circulation line 35...Suction side line 37...Use side heat exchanger 38...Return side line 39...Second pline circulation line 40.41...・Three-way switching valve 42.43...Bypass line 1.1-;',,,22' Fig. 1

Claims (1)

[Claims] A refrigerant circulation path in which refrigerant is circulated by a compressor driven by an engine, a first pline circulation path in which the refrigerant circulates through a water-cooled condenser, a buffer tank, etc., and a user-side heat exchange by sucking pline from the buffer tank. and a second pline circulation path that flows through the tank and returns to the buffer tank again.
A three-way switching valve is provided in each of the return side and outlet side pipes of the buffer tank of the prine circulation path, and a bypass pipe is connected to the suction side and return side pipes of the second prine circulation path, respectively, via the three-way switching valve. 1. An engine heat pump device characterized in that a three-way switching valve is provided to flow the pline into a bypass pipe when the temperature of the prine in a buffer tank is low.