JP3091682B2 - Engine driven heat pump device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine-driven heat pump device in which a compressor for compressing a refrigerant is driven by a gas engine or the like, and more particularly, to a circuit for cooling an engine provided with an exhaust gas heat exchanger. The present invention relates to an engine-driven heat pump device.

[0002]

2. Description of the Related Art As this type of technology, for example, as shown in FIG. 3, an engine 2 for driving a compressor 1 for compression of a refrigerant and an outdoor heat exchanger of a heat pump refrigerant circuit (not shown) are provided side by side. A radiator 3 for exchanging heat with the outside air
A pump P1 and an exhaust gas heat exchanger 4 for exchanging heat between exhaust gas and cooling water generated when the engine 2 is driven are connected to a series closed circuit by a cooling water pipe 5, and the engine 2 and the radiator 3 are connected. A thermo valve V1 (for example, a three-port automatic switching valve)
A wax valve) is provided, and the remaining connection port of the thermo valve V1 is connected to the cooling water pipe 5d between the exhaust gas heat exchanger 4 and the engine 2 by a bypass pipe 6. Further, the cooling water pipe 5a is connected to the engine 2 side. An engine-driven heat pump device is known in which the cooling water pipe 5d and the engine 2 side are connected by a bypass pipe 7 having a pump P2.

The temperature of the cooling water flowing from the engine 2 side is set to a predetermined temperature, for example, 60 ° C.
In the following cases, the flow path from the engine 2 to the radiator 3 is completely closed, the bypass pipe 6 → the flow path from the radiator 3 is fully opened, and the temperature of the cooling water flowing from the engine 2 side is higher than 60 ° C. For example, when the temperature is 70 ° C. or more, the flow path from the engine 2 to the radiator 3 is fully opened, the flow path from the bypass pipe 6 to the radiator 3 is completely closed, and the temperature of the cooling water flowing from the engine 2 side is 60 to When the temperature is between 70 ° C., the function is such that as the temperature increases, the flow path from the engine 2 to the radiator 3 opens proportionally, and the flow path from the bypass pipe 6 to the radiator 3 closes proportionally.

Accordingly, when the temperature of the cooling water discharged by cooling the engine 2 is low, the engine 2 in the engine-driven heat pump apparatus having the above-described structure passes through the bypass pipe 7 without being radiated to the outside air by the radiator 3. When the temperature is high, it is effectively cooled by the cooling water radiated by the radiator 3.

On the other hand, 60 exhausted through the exhaust pipe 2A
Exhaust gas of the engine 2, which reaches 0 ° C., is effectively cooled in the exhaust gas heat exchanger by cooling water constantly radiated to the outside air by the radiator 3, and can be cooled to a required temperature or lower.

[0006]

However, in the above-mentioned conventional engine-driven heat pump device, the temperature of the outside air is greatly reduced, and the cooling water passing through the exhaust gas heat exchanger is radiated by the radiator without passing through the inside of the engine. When the exhaust gas is recirculated to the exhaust gas heat exchanger, the temperature of the exhaust gas becomes too low, and there is a problem that water vapor contained in the exhaust gas freezes at the outlet of the exhaust pipe, and such a problem does not occur in a cold region. I needed to do that.

[0007]

According to the present invention, as a specific means for solving the above-mentioned problems of the prior art, a radiator for exchanging heat with outside air and an exhaust gas for exchanging heat with exhaust gas emitted from an engine are provided. With an engine configured to be able to be cooled by a cooling fluid circulating in a cooling circuit having a heat exchanger,
In an engine-driven heat pump device that drives a compressor for refrigerant compression,

The cooling circuit is configured so that the cooling fluid flows back to the engine via the radiator and the exhaust gas heat exchanger in this order, and a cooling circuit is provided between the engine and the radiator in the cooling circuit. Two 3-port automatic temperature switching valves are installed in series, and the remaining connection port of the first automatic temperature switching valve installed on the engine side is connected to the exhaust gas heat exchanger outlet pipe of the cooling circuit. A first bypass pipe, which is branched and extended, is connected, and the remaining connection port of the second automatic temperature switching valve installed on the side of the radiator branches off from the radiator outlet side pipe of the cooling circuit. A second bypass pipe extending from the cooling circuit, and connecting the engine outlet pipe and the inlet pipe of the cooling circuit by a third bypass pipe having a pump. Heat And the pump apparatus,

[0009] In the engine-driven heat pump device having the first configuration, the first temperature automatic switching valve may include:
When the temperature of the cooling fluid flowing through the engine is equal to or lower than the first predetermined temperature, only the cooling fluid that has passed through the first bypass pipe flows toward the radiator, and the second cooling fluid that is higher than the first predetermined temperature is used. When the temperature is equal to or higher than the predetermined temperature, only the cooling fluid that has passed through the engine flows to the radiator side. When the temperature is between the first predetermined temperature and the second predetermined temperature, the engine is operated as the temperature increases. A temperature automatic switching valve that increases the amount of cooling fluid flowing to the radiator through the first bypass pipe and decreases the amount of cooling fluid flowing to the radiator through the first bypass pipe; As a second temperature automatic switching valve, when the temperature of the cooling fluid flowing from the side of the first temperature automatic switching valve is equal to or lower than a third predetermined temperature, the entire amount flows to the second bypass pipe side;
When the temperature is equal to or higher than a fourth predetermined temperature that is higher than the third predetermined temperature, the entire amount is caused to flow toward the radiator, and when the temperature is between the third predetermined temperature and the fourth predetermined temperature, the higher the temperature, An engine-driven heat pump device having a second configuration, wherein a temperature automatic switching valve is used to increase the amount of cooling fluid flowing to the side of the radiator and decrease the amount of cooling fluid flowing to the side of the second bypass pipe. When,

The cooling circuit is configured so that the cooling fluid returns to the engine via the radiator and the exhaust gas heat exchanger in this order, and the cooling circuit is provided between the engine and the radiator in the cooling circuit. A three-port automatic temperature switching valve is installed, an electric three-way switching valve is installed between the radiator of the cooling circuit and the exhaust gas heat exchanger, and the remaining connection port of the automatic temperature switching valve is A refrigerant heat exchanger for connecting a bypass pipe extending from the exhaust gas heat exchanger inlet side pipe of the cooling circuit to a remaining connection port of the electric three-way switching valve to exchange heat with a refrigerant flowing back to the compressor. And a third heat exchanger tube for refrigerant connected from the exhaust gas heat exchanger inlet side pipe of the cooling circuit.
An engine-driven heat pump device having a configuration of

In the engine-driven heat pump apparatus having the third configuration, when the temperature of the cooling fluid flowing through the engine is equal to or lower than a first predetermined temperature, the entire amount flows to the bypass pipe side as an automatic temperature switching valve. When the temperature is equal to or higher than a second predetermined temperature higher than the first predetermined temperature, the entire amount is caused to flow toward the radiator. When the temperature is between the first predetermined temperature and the second predetermined temperature, the higher the temperature, the higher the temperature. Using an automatic temperature switching valve that increases the amount of cooling fluid flowing to the side of the radiator and reduces the amount of cooling fluid flowing to the side of the bypass pipe, an electric three-way switching valve controls the amount of cooling fluid flowing from the radiator. A switching valve that allows the entire amount to flow to the refrigerant heat exchanger side or bypasses the refrigerant heat exchanger and allows the entire amount to flow directly to the exhaust gas heat exchanger, returning to the outside air temperature, the indoor heat exchanger temperature, and the compressor. To solve the above-described problems of the related art by providing an engine-driven heat pump device having a fourth configuration, which is provided with a controller that operates the electric three-way switching valve based on the pressure of the refrigerant or the like. It is.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an engine-driven heat pump apparatus according to the present invention will be described below with reference to FIGS. In addition, in order to facilitate understanding, in these figures, parts having the same functions as those described in FIG. 3 are denoted by the same reference numerals.

A first embodiment will be described with reference to FIG. In the engine-driven heat pump device illustrated in FIG. 1, a cooling water pipe 5a between the thermo-valve V1 and the radiator 3 is connected to a thermo-valve V2 (for example, a wax valve) which is another three-port automatic temperature switching valve. ) And the remaining connection port of the thermo valve V2,
The cooling water pipe 5 b between the radiator 3 and the pump P 1 is connected via a bypass pipe 8.

When the temperature of the cooling water flowing from the side of the thermo valve V1 is lower than a predetermined temperature, for example, 60.degree. C., the entire amount flows to the bypass pipe 8. When the temperature of the cooling water is 70.degree. To the radiator 3 side, and when the temperature is between 60 and 70 ° C., the higher the temperature is, the more the amount flowing through the radiator 3 increases and the amount flowing through the bypass pipe 8 decreases proportionally. Use something that works.

During the period from the engine 2 of the cooling water pipe 5a to the thermo-valve V2, the cooling water whose temperature has increased through the interior of the engine 2 is convected by the thermo-valves V1.V
It is desirable that the pipes be provided with an upward slope so that the pipes can easily flow in the two directions. When piping the cooling water pipe 5a horizontally (even when piping it up and down), the junction between the cooling water pipe 5a and the bypass pipe 7 and the thermo valves V1 and V2 are installed close to each other so that heat is easily transmitted. It is desirable to do.

When the temperature of the cooling water passing through the thermovalve V2 is higher than a predetermined value of 70 ° C., the cooling water whose heat has been radiated by the radiator 3 and whose temperature has decreased is discharged to the exhaust gas heat exchanger 4. When the temperature is lower than a predetermined temperature of 60 ° C., the cooling water bypassing the radiator 3 and having not decreased in temperature flows into the exhaust gas heat exchanger 4,
When the temperature is between 70 ° C., the radiator 3
The flow ratio between the exhaust gas and the bypass pipe 8 is controlled and flows into the exhaust gas heat exchanger 4, so that the exhaust gas of the engine 2 exhausted through the exhaust pipe 2A is not excessively cooled in the exhaust gas heat exchanger 4. . Therefore, even in a cold region, the water vapor contained in the exhaust gas does not freeze at the outlet of the exhaust pipe 2A.

Further, even when the temperature of the cooling water for cooling the engine 2 is low, the cooling water circulated by the pump P1 circulates and cools the exhaust gas heat exchanger 4, and the cooling water circulated by the pump P2 cools the engine 2 Circulating and cooling, the exhaust gas heat exchanger 4 does not have the disadvantage that the cooling water boils at the exhaust gas inlet side where exhaust gas as high as 600 ° C. flows. Is continued.

That is, in the present invention, the cooling water is supplied to the radiator 3,
The exhaust gas heat exchanger 4 is provided so as to return to the engine 2 via the exhaust gas heat exchanger 4 in order, and can also flow around the radiator 3 and the engine 2 respectively. As a result, the water vapor contained in the exhaust gas does not freeze, the cooling water does not boil due to insufficient cooling, and the engine 2 does not have excessive or insufficient cooling.

A second embodiment will be described with reference to FIG. The engine-driven heat pump device illustrated in FIG. 2 differs from the engine-driven heat pump device of the first embodiment illustrated in FIG.
And the bypass pipe 7 having the pump P2 is removed, and the heat exchange pipe 10 for the refrigerant having the refrigerant heat exchanger 9 for exchanging heat between the cooling water and the refrigerant and the electric three-way switching valve V3 are installed. The cooling water radiated by the radiator 3 is configured to flow into the refrigerant heat exchanger 9 or to flow directly into the exhaust gas heat exchanger 4 bypassing the refrigerant heat exchanger 9.

The refrigerant heat exchanger 9 is, for example, formed as a double pipe in which the refrigerant flows inside and the cooling water flows outside, and a heat pump refrigerant such that the refrigerant returning to the compressor 1 passes through the inside refrigerant passage. The circuit 11 is connected by piping. In addition, 12 is an accumulator, 13 is a four-way switching valve.

A temperature sensor S for detecting the temperature of the outside air
1, a temperature sensor S2 for detecting the temperature of an indoor heat exchanger (not shown), and a pressure sensor S3 for detecting the pressure of the refrigerant sucked by the compressor 1, and based on signals detected and output by these sensors. And a controller 14 for controlling the switching of the electric three-way switching valve V3.

In any of the cooling and heating operations, for example, at the start of the operation, the controller 14 allows the entire amount of the cooling water flowing out of the radiator 3 to bypass the refrigerant heat exchange pipe 10 and exhaust gas. Operate the electric three-way switching valve V3 so as to directly flow into the heat exchanger 4,

During the heating operation, when the temperature of the outside air detected by the temperature sensor S1 drops to a predetermined temperature, for example, 2 ° C. or less, all the cooling water flowing out of the radiator 3 flows into the heat exchange pipe 10 for refrigerant. After operating the electric three-way switching valve V3 so as to pass through the refrigerant heat exchanger 9, and operating the electric three-way switching valve V3 in this manner, the pressure detected by the pressure sensor S3 has increased to a predetermined pressure, for example, 250 kPa or more. sometimes,
The electric three-way switching valve V3 is operated such that all the cooling water flowing out of the radiator 3 bypasses the refrigerant heat exchanger 9 and directly flows into the exhaust gas heat exchanger 4,

In the cooling operation, when the temperature of the indoor heat exchanger (not shown) detected by the temperature sensor S2 falls to a predetermined temperature, for example, 2 ° C. or less, all the cooling water flowing out of the radiator 3 is exchanged for the refrigerant heat exchange. Flow through the pipe 10 and the refrigerant heat exchanger 9
After operating the electric three-way switching valve V3 so as to pass through, and operating the electric three-way switching valve V3 in this manner, the temperature of the indoor heat exchanger rises to a predetermined temperature higher than the predetermined temperature, for example, 3 ° C. or more. At this time, switching control such as operating the electric three-way switching valve V3 such that all the cooling water flowing out of the radiator 3 bypasses the refrigerant heat exchanger 9 and directly flows into the exhaust gas heat exchanger 4 can be performed. Constitute.

Therefore, in the engine-driven heat pump apparatus having the above-described structure, when the temperature of the cooling water passing through the thermovalve V2 is higher than the predetermined 70 ° C.,
When the temperature is lower than a predetermined temperature of 60 ° C., the cooling water whose temperature has not decreased by flowing around the radiator 3 flows into the exhaust gas heat exchanger 4. When the temperature is between 60 and 70 ° C., the ratio flowing between the radiator 3 and the bypass pipe 8 is controlled based on the temperature and flows into the exhaust gas heat exchanger 4, so that the exhaust gas is exhausted through the exhaust pipe 2A. The exhaust gas of the engine 2 is not excessively cooled in the exhaust gas heat exchanger 4. Therefore, even in a cold region, the water vapor contained in the exhaust gas does not freeze at the outlet of the exhaust pipe 2A.

Further, even when the temperature of the cooling water for cooling the engine 2 is low, the radiator 3 is driven by the driving force of the pump P1.
Since the cooling water circulating around the exhaust gas is continuously supplied to the exhaust gas heat exchanger 4, the cooling water boils on the exhaust gas inlet side of the exhaust gas heat exchanger 4 into which the exhaust gas of 600 ° C. flows. Nor.

Further, since the electric three-way switching valve V3 which operates as described above is installed by the controller 14, the cooling water which has a reduced amount of heat radiation to the outside air is stopped by stopping the blower (not shown) installed facing the radiator 3. Can be sent to the refrigerant heat exchanger 9 to exchange heat with the refrigerant, thereby increasing the pressure of the low-pressure side refrigerant, and improving the heating capacity when the air temperature drops significantly. Also, during a cooling operation performed when the air temperature is considerably low (this is often necessary in a room equipped with OA equipment, etc.), the freezing of the indoor heat exchanger can be prevented, so that the operable lower limit outside air temperature Can be reduced.

Since the present invention is not limited to the above embodiment, various modifications can be made without departing from the scope of the claims.

For example, the controller 14 may be configured to control the electric three-way switching valve V3 simply based on the low-pressure side pressure data detected and output by the pressure sensor S3.

[0030]

As described above, according to the engine-driven heat pump device of the present invention, when the temperature of the cooling water is high, the cooling water whose heat is radiated by the radiator and whose temperature is lowered flows into the exhaust gas heat exchanger, and the temperature of the cooling water decreases. When the temperature is low, the cooling water that bypasses the radiator and does not drop in temperature flows into the exhaust gas heat exchanger, so that the exhaust gas of the engine exhausted through the exhaust pipe may be excessively cooled in the exhaust gas heat exchanger. Absent.

Therefore, even in a cold region, the water vapor contained in the exhaust gas does not freeze at the outlet. In addition, since the cooling water circulates through the exhaust gas heat exchanger and keeps cooling, there is no inconvenience that the cooling water boils at the exhaust gas inlet side, and required cooling can be performed on the engine.

Further, in the engine driven heat pump device according to the third and fourth aspects, it is possible to improve the heating capacity when the air temperature drops significantly, and to perform the cooling operation (OA) when the air temperature is considerably low. In many cases, such as in an indoor room equipped with equipment, it is possible to prevent the indoor heat exchanger from freezing, and to lower the operable lower-limit outside air temperature.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a first embodiment.

FIG. 2 is an explanatory diagram showing a second embodiment.

FIG. 3 is an explanatory diagram showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Engine 2A Exhaust pipe 3 Radiator 4 Exhaust gas heat exchanger 5.5, 5a, 5b, 5c, 5d Cooling water pipe 6, 7, 8 Bypass pipe 9 Refrigerant heat exchanger 10 Heat exchange pipe for refrigerant 11 Heat pump refrigerant circuit 12 Accumulator 13 Four-way switching valve 14 Controller P1, P2 Pump S1, S2 Temperature sensor S3 Pressure sensor V1, V2 Thermovalve V3 Electric three-way switching valve

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F25B 27/02 F01N 5/02 F25B 27/00 F24F 5/00

Claims (4)

(57) [Claims] An engine configured to be capable of being cooled by a cooling fluid circulating in a cooling circuit including a radiator for performing heat exchange with outside air and an exhaust gas heat exchanger for performing heat exchange with exhaust gas emitted from the engine. An engine-driven heat pump device that drives a compressor for refrigerant compression, wherein the cooling fluid is configured to return to the engine via the radiator and the exhaust gas heat exchanger in this order, and A three-port automatic switching valve is connected in series between the engine and the radiator of the cooling circuit.
A first bypass pipe, which is installed separately from the first exhaust gas heat exchanger outlet pipe of the cooling circuit and extends to the remaining connection port of the first automatic temperature switching valve installed on the engine side. A second bypass pipe, which is connected to and extends from the radiator outlet-side pipe of the cooling circuit, is connected to the remaining connection port of the second automatic temperature switching valve installed on the side of the radiator. An engine-driven heat pump device, wherein the engine outlet pipe and the inlet pipe of the cooling circuit are connected by a third bypass pipe having a pump. 2. A first temperature automatic switching valve, wherein when the temperature of the cooling fluid flowing through the engine is equal to or lower than a first predetermined temperature, only the cooling fluid passing through the first bypass pipe is used as the first radiator. When the temperature is equal to or higher than a second predetermined temperature that is higher than the first predetermined temperature, only the cooling fluid that has passed through the engine flows to the radiator side, and the first predetermined temperature and the second predetermined temperature When the temperature is between the temperatures, the higher the temperature, the greater the amount of cooling fluid flowing to the radiator through the engine, and the more the cooling fluid flows to the radiator through the first bypass pipe. A temperature automatic switching valve for reducing the amount of fluid is used, and as a second temperature automatic switching valve, when the temperature of the cooling fluid flowing from the side of the first temperature automatic switching valve is equal to or lower than a third predetermined temperature, the entire amount is reduced. To the side of the second bypass pipe,
When the temperature is equal to or higher than a fourth predetermined temperature that is higher than the third predetermined temperature, the entire amount is caused to flow toward the radiator, and when the temperature is between the third predetermined temperature and the fourth predetermined temperature, the higher the temperature, The engine-driven heat pump device according to claim 1, wherein an automatic temperature switching valve that increases an amount of the cooling fluid flowing toward the radiator and decreases an amount of the cooling fluid flowing toward the second bypass pipe is used. 3. An engine configured to be capable of being cooled by a cooling fluid circulating in a cooling circuit including a radiator for performing heat exchange with outside air and an exhaust gas heat exchanger for performing heat exchange with exhaust gas emitted from the engine. An engine-driven heat pump device that drives a compressor for refrigerant compression, wherein the cooling fluid is configured to return to the engine via the radiator and the exhaust gas heat exchanger in this order, and A three-port automatic temperature switching valve is installed between the engine and the radiator of the cooling circuit,
An electric three-way switching valve is installed between the radiator and the exhaust gas heat exchanger of the cooling circuit, and the remaining connection port of the automatic temperature switching valve is connected to the exhaust gas heat exchanger inlet side pipe of the cooling circuit. An extended bypass pipe is connected, and the remaining connection port of the electric three-way switching valve is provided with a refrigerant heat exchanger for performing heat exchange with the refrigerant flowing back to the compressor in the middle thereof, and the exhaust gas heat of the cooling circuit is provided. An engine-driven heat pump device, wherein a heat exchange pipe for refrigerant extending from an exchanger inlet side pipe is connected. 4. When the temperature of a cooling fluid flowing through an engine is equal to or lower than a first predetermined temperature, the entire amount flows to a bypass pipe side as an automatic temperature switching valve.
When the temperature is equal to or higher than a second predetermined temperature higher than the predetermined temperature, the entire amount is flowed to the radiator side, and the first predetermined temperature and the second
When the temperature is higher than the predetermined temperature, using a temperature automatic switching valve for increasing the amount of cooling fluid flowing to the radiator side and decreasing the amount of cooling fluid flowing to the bypass pipe side as the temperature is higher, As a three-way switching valve, a switching valve that allows the entire amount of the cooling fluid flowing from the radiator to flow toward the refrigerant heat exchanger or bypasses the refrigerant heat exchanger and directly flows the entire amount to the exhaust gas heat exchanger, The engine-driven heat pump device according to claim 3, further comprising a controller that operates the electric three-way switching valve based on a temperature, an indoor heat exchanger temperature, a pressure of a refrigerant flowing back to the compressor, and the like.