Gas engine air-conditioning device

Abstract

PURPOSE: To improve efficiency of forward and reverse rotation of a second fan 64 in a gas engine air-conditioning device that operates an air-conditioning device efficiently using a small-sized gas engine and a DC generator.CONSTITUTION: A gas engine air-conditioning device comprises a comprehensive housing 9 including: a gas engine 1; a first cooling water circulation path 51; a second cooling water circulation path 52; a first radiator 61; a second radiator 62; a water path switching valve 53; the gas engine 1; a DC generator 2; a motor 3; a compressor 41; a condenser 42; a first fan 63 that rotates only in a forward direction; and a second fan 64 that rotates in both forward and reverse directions. The gas engine air-conditioning device is configured so that surplus power from the DC generator 2 is supplied to the outside as an AC power source. During heating / cooling and during overheating, the second fan 64 can rotate in both forward and reverse directions, and an angle of attack α+β of the second fan 64 for forward and reverse rotation is the same, while both end parts of blades are bent at the same angle α.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gas engine air conditioner that uses a small gas engine and a DC generator to efficiently operate the air conditioner. [Background technology]

[0002] In recent years, systems that use gas engines to operate air conditioners have become more common. Air conditioners that use heat pumps are also on the rise. Air conditioners have a compressor in the refrigerant circuit. A gas engine drives this compressor. This type of system is called a gas engine heat pump. This type of air conditioner has the advantage of being able to operate at low cost. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-257102 A [Patent Document 2] JP 2003-4332 A Summary of the Invention [Problem to be solved by the invention]

[0004] In air conditioning and heating equipment that runs on a gas heat pump using a gas engine, there are many configurations in which the gas engine and the compressor are directly connected to drive the compressor. This configuration also includes the following configurations. First, there is a configuration in which the drive shaft of the gas engine and the rotating shaft of the compressor are directly connected. Second, there is a configuration in which rotation is transmitted between the gas engine and the compressor via a belt. Third, there is a configuration in which rotation is transmitted between the gas engine and the compressor via a chain.

[0005] These systems either directly connect the gas engine to the compressor or use a belt or chain, and in either case, the rotation of the gas engine is directly transmitted to the compressor, giving the compressor more power than necessary. Most of the power given to the compressor is too much for the operation of the heating and cooling system, resulting in power waste. Furthermore, the vibrations caused by the gas engine during operation are transmitted to the compressor, which can place an excessive burden on the compressor. Furthermore, the operation of the compressor becomes unstable due to torque fluctuations caused by the gas engine during operation.

[0006] In addition, if rotation is transmitted by a belt or chain between the gas engine and the compressor, it may be necessary to adjust the tension of the belt or chain appropriately, and space may be required on the gas engine for the belt or chain, which will have a significant impact on management costs.

[0007] Furthermore, in air conditioning and heating equipment that runs on a gas heat pump using a gas engine, the center of the housing in which the equipment is housed can easily become extremely hot due to the heat from the gas engine, generator, and other equipment, and the refrigerant temperature at the condenser (heat exchanger) inlet can become too low during heating. This makes it extremely difficult to control the temperature of the refrigerant used for heating and cooling. Furthermore, when overheating occurs, the center of the housing in which the equipment is housed can easily become extremely hot, so there is a demand for an efficient air blowing configuration with a devised fan structure.

[0008] The problem (technical problem or objective, etc.) that this invention aims to solve is to eliminate the inconvenience caused by directly connecting the rotation transmission mechanism of the gas engine and the compressor, as described above, and to provide a gas engine heating and cooling device that further improves the operating efficiency of heating and cooling powered by a gas heat pump using a gas engine, while also requiring an innovative fan structure inside the casing to function in the event of overheating. [Means for solving the problem]

[0009] Therefore, the inventors have conducted intensive research to solve the above problems, and as a result, have found the invention of claim 1 to be a gas engine heating and cooling device having an overall housing having a gas engine, a first cooling water circulation flow path and a second cooling water circulation flow path through which cooling water of the gas engine circulates, a first radiator provided in the first cooling water circulation flow path, a second radiator provided in the second cooling water circulation flow path, a water path switching valve for circulating the cooling water to either the first cooling water circulation flow path or the second cooling water circulation flow path, a DC generator driven by the gas engine, a motor operated by the DC generator, a compressor driven by the motor and compressing a refrigerant, a condenser for heat exchange with the refrigerant, a first fan that rotates only in the forward direction to provide a passing air to the first radiator, and a second fan that rotates in the forward and reverse directions to also provide a passing air to the second radiator, The second fan causes passing air to flow in one direction from the first radiator side to the second radiator side, and surplus power from the DC generator is supplied to the outside as AC power, and in the event of overheating, the water path switching valve causes cooling water to flow into the second cooling water circulation flow path, and the first fan rotating in the forward direction and the second fan rotating in the forward direction cause passing air to be introduced into the overall housing to ventilate, the second fan has a plurality of blades, each of which has a flat blade center portion in the middle along the rotation direction and has blade ends at both ends in the rotation direction of the blade center portion, the angle of attack of the blade center portion of the second fan being α+β, and both blade ends of the blades are bent at the same angle α, and the second fan can ensure the same air volume in both forward and reverse rotations. This solves the above problem.

[0010] The invention of claim 2 solves the above problem by providing a gas engine air conditioning and heating system in accordance with claim 1, characterized in that the number of blades of the second fan is four. The invention of claim 3 solves the above problem by providing a gas engine air conditioning and heating system in accordance with claim 1, characterized in that the number of blades of the second fan is three. The invention of claim 4 solves the above problem by providing a gas engine air conditioning and heating system in accordance with claim 1 or 2, characterized in that the angle of attack α+β of the blades of the second fan is 30 degrees, and α is 25 degrees. Effect of the Invention

[0011] In the invention of claim 1, the gas engine does not directly drive the compressor, but the electric power of the generator is increased or decreased by adjusting the excitation electricity in the TCU (total controller), and this electric power is supplied to the DC motor that drives the compressor, and during heating, the heat exchanger part of the indoor unit is heated with the heated air. Therefore, in a system in which the compressor is directly driven by a gas engine, the compressor has a surplus capacity that exceeds the heat exchange capacity (kW) of the indoor unit, and power is wasted. This type of waste can be avoided.

[0012] Also, using a gas engine to drive multiple compressors with belts or chains results in a lot of waste in terms of power transmission and space, and also transmits adverse effects such as vibration, but this system can eliminate these inconveniences.Furthermore, because the compressors are not directly driven by the gas engine, there is no need to worry about vibration caused by interference between the torque fluctuations of the gas engine and the cogging of the compressor (the awkward clicking motion that accompanies compression).

[0013] In the present invention of claim 1, in the event of overheating, the first fan and the second fan are used to introduce ventilation air into the overall housing for ventilation, while the second fan is rotated in the forward direction, and the angle of attack α+β of the second fan in the forward and reverse rotations is made the same, while both ends of the blades are bent at the same angle α. This makes it possible to improve the air blowing efficiency of the second fan in the forward and reverse rotations, and is particularly effective in avoiding overheating or a state similar to this during high temperatures in summer, and reliably prevents overheating.

[0014] In addition, the inventions of claims 2 and 3 provide the same effect whether the blades are four or three. Furthermore, in the invention of claim 4, the second fan angle of attack α+β is set to the same 30 degrees, while both ends of the blades are bent at the same angle α of 25 degrees, which has the advantage that a gas engine air conditioner equipped with a fan that can rotate in both forward and reverse directions efficiently can be manufactured inexpensively and simply. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1A is a system diagram of a gas engine air conditioner according to the present invention, and FIG. 1B is a schematic diagram showing the configuration of output control from a DC generator to a DC motor by a controller in FIG. [Diagram 2] 1 is an overall system diagram showing the operating state of a gas engine heating and cooling device according to the present invention during heating. [Diagram 3] FIG. 4 is an operational diagram showing the flow of refrigerant during heating in the gas engine cooling and heating device of the present invention. [Figure 4] FIG. 2 is an operational diagram showing the direction of air passing through the first radiator and the condenser by the first fan on the compressor unit side during heating in the gas engine air conditioner of the present invention. [Diagram 5] 1 is an overall system diagram showing the operating state of a gas engine cooling and heating device according to the present invention during cooling. [Figure 6] FIG. 4 is an operational diagram showing the flow of refrigerant during cooling in the gas engine cooling and heating device of the present invention. [Figure 7]FIG. 2 is an operational diagram showing the direction of air passing through the first radiator and condenser by the first fan on the compressor unit side during cooling in the gas engine air conditioner of the present invention. [Figure 8] 1A, 1B, and 1C are diagrams showing a configuration in which a general housing that houses a power unit and a compressor unit is cooled by a first fan and a second fan. [Figure 9] 1A is a front view of the second fan that rotates forward and backward, FIG. 1B is a side view of the second fan, FIG. 1C is a cross-sectional view taken along the line X1-X1 of FIG. 1A, FIG. 1D is an enlarged view of the blade portion of FIG. 1C, and FIG. 1E is a perspective view of a partial cross-section of the blade portion of the fan. [Figure 10] FIG. 1A is a front view of another embodiment of a second fan that rotates forward and backward, FIG. 1B is a side view of the second fan, FIG. 1C is an enlarged cross-sectional view of the blade portion of FIG. 1B, and FIG. 1D is a cross-sectional view of the central essential portion where the second fan is attached to the motor. [Figure 11] 10(A) is a cross-sectional view and a perspective view taken along the Y1-Y1 arrows in FIG. 10(A), (B) is a perspective view of FIG. 10(A), (C) is a cross-sectional view of one blade in (B), and (D) is a front view of yet another embodiment of the second fan. [Figure 12] FIG. 1 is a system diagram of a gas engine cooling and heating system according to the present invention in which the power unit and compressor unit are housed in separate housings. [Figure 13] FIG. 2 is a system diagram showing a configuration in which a plurality of compressor units are arranged in parallel with respect to one power unit in a gas engine cooling and heating system according to the present invention. [Figure 14] 1A is a partially cross-sectional side view of the coupling, the flywheel, and the DC generator separated from each other, FIG. 1B is a longitudinal side view of the coupling, FIG. 1C is a front view of the coupling, and FIG. 1D is a cross-sectional view taken along the line Y1-Y1 of FIG. 1B. [Figure 15] 1 is a schematic diagram showing the configuration of a gas engine. [Figure 16] 4A is a side view with a portion cut away of a main refrigerant passage switching valve and a sub refrigerant passage switching valve, and FIG. 4B is a cross-sectional plan view of FIG. [Figure 17]1A to 1C are diagrams illustrating the configuration of a DC motor and a controller. [Figure 18] FIG. 1A is a system diagram of an embodiment of a gas engine heating and cooling device that uses an AC generator and an AC motor, and FIG. 1B is a schematic diagram showing the configuration of output control from the AC generator to the AC motor by the controller of FIG. [Figure 19] FIG. 1 is an overall system diagram showing an operating state during heating in an embodiment using an AC generator and an AC motor. [Figure 20] FIG. 2A is a diagram showing a configuration for controlling an AC generator and an AC motor, and FIG. 2B is a detailed view of part (α) in FIG. [Figure 21] FIG. 1A is a system diagram of an embodiment of a gas engine heating and cooling system that uses an AC generator and a DC motor, and FIG. 1B is a schematic diagram showing the configuration of output control from the AC generator to the DC motor by the controller of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The present invention is mainly composed of a power unit A1 and a compressor unit A2, to which an indoor unit is added (see Figs. 1, 2, 5, etc.). The power unit A1, the compressor unit A2, and a housing (a general housing 9 or a first housing 91) described later constitute an outdoor unit A. The power unit A1 is composed of a gas engine 1, a DC generator 2, a first cooling water circulation flow path 51, a second cooling water circulation flow path 52, a second radiator 62, and a second fan 64 (see Figs. 1, 2, 5, etc.). Here, the outdoor unit A is often installed indoors in a building of a collective housing such as a building, a condominium, or an apartment, and is often installed in, for example, a basement or a machine room of a building. It may also be installed outdoors of a building like a normal air conditioner.

[0017] The compressor unit A2 is constituted by an assembly of a motor 3, a compressor 41, a first radiator 61, a condenser 42, and a first fan 63. The indoor unit is constituted by a refrigerant flow path 72 and an indoor unit 71, etc. Here, the motor 3 will be described below as a DC motor, but in the present invention, an embodiment of the motor 3 may also be an AC motor 3A, and the AC motor 3A will be described at the end of the description.

[0018] In the following description, motor 3 is a DC motor, and when motor 3 is an AC motor, the reference number 3A is added and the motor is described as an AC motor 3A. In the following description, where it is emphasized that motor 3 is a DC motor, it is described as a DC motor 3. Furthermore, in the drawings, motor 3 is described as a DC motor in an embodiment in which a DC motor is used, and is described as an AC motor in an embodiment in which an AC motor is used.

[0019] The power unit A1 and the compressor unit A2 are connected to each other so that the coolant for the gas engine 1 can circulate through a first coolant circulation flow path 51 (see Figs. 1, 2, 5, etc.). The compressor unit A2 is also connected to a refrigerant flow path 72 between itself and an indoor unit 71. The refrigerant flow path 72 includes a heating refrigerant flow path 72a and a cooling refrigerant flow path 72b. The heating refrigerant flow path 72a is a flow path (pipe) through which the refrigerant flows during heating (see Figs. 2 to 4), and the cooling refrigerant flow path 72b is a flow path (pipe) through which the refrigerant flows during cooling (see Figs. 5 to 7).

[0020] The compressor unit A2 and the heating refrigerant flow path 72a or the cooling refrigerant flow path 72b serve to supply refrigerant in a state suitable for heating or cooling to the indoor unit 71. The power unit A1 and the compressor unit A2 are incorporated together in a single overall housing 9. The power unit A1, the compressor unit A2, and the overall housing 9 constitute the outdoor unit A.

[0021] The condenser 42 may be called a heat exchanger. That is, during heating, the condenser 42 functions as a heat exchanger that obtains heat from the air and raises the temperature of the refrigerant gas at the inlet of the compressor 41. During cooling, the condenser 42 serves to expose the heat of the refrigerant gas, which has been compressed and heated by the compressor 41, to passing air, thereby condensing the refrigerant gas into a liquid.

[0022] In the power unit A1, the gas engine 1 and the DC generator 2 are connected by a coupling 14, and the DC generator 2 generates electricity when the gas engine 1 is driven (see FIG. 1). The electric power generated by the DC generator 2 is transmitted to the compressor unit A2 side and supplied to the motor 3 via a controller 35. In the compressor unit A2 side, the motor 3 drives the compressor 41.

[0023] The gas engine 1 of the power unit A1 is provided with a first cooling water circulation path 51 and a second cooling water circulation path 52 (see Figs. 1 to 7, etc.). Cooling water circulates through both the first cooling water circulation path 51 and the second cooling water circulation path 52, and the first cooling water circulation path 51 and the second cooling water circulation path 52 are configured such that the cooling water flows through only one of the circulation paths by a water path switching valve 53 (see Figs. 1 to 7).

[0024] The first coolant circulation flow path 51 is a flow path arranged across both the power unit A1 and the compressor unit A2, with the gas engine 1 at the center. The second coolant circulation flow path 52 is a flow path arranged only in the gas engine 1 of the power unit A1. In the outdoor unit A, the coolant circulates through the first coolant circulation flow path 51 during heating, and the coolant circulates through the second coolant circulation flow path 52 during cooling.

[0025] The first cooling water circulation flow path 51 is provided between the power unit A1 and the compressor unit A2, and cools the gas engine 1 and also manages the temperature of the condenser 42. The second cooling water circulation flow path 52 cools the gas engine 1 in the power unit A1 when it is running. The cooling water flows through either the first cooling water circulation flow path 51 or the second cooling water circulation flow path 52 due to the water path switching valve 53, and does not flow through both simultaneously.

[0026] The first coolant circulation flow path 51 and the second coolant circulation flow path 52 share a flow path on the inlet side and part of the outlet side from the gas engine 1 (see Fig. 1(A), Fig. 2, Fig. 3, etc.). A water path switching valve 53 is provided in the outlet side flow path. The water path switching valve 53 is operated by a TCU (total control unit) 66 to switch to either the first coolant circulation flow path 51 or the second coolant circulation flow path 52 depending on whether heating or cooling is performed.

[0027] The second coolant circulation flow path 52 is provided in the gas engine 1 of the power unit A1, and a second radiator 62 is provided in the second coolant circulation flow path 52. The second radiator 62 is provided with a second fan 64, and the second fan 64 provides a passing wind to the second radiator 62. The second coolant circulation flow path 52 only cools the gas engine 1.

[0028] The first coolant circulation flow path 51 is disposed between the power unit A1 side and the compressor unit A2 side, and a first radiator 61 is provided in the first coolant circulation flow path 51, and a first fan 63 is provided adjacent to the first radiator 61. The condenser 42 is disposed between the first radiator 61 and the first fan 63. The first fan 63 provides a passing wind to the first radiator 61, and the passing wind affects the temperature of the condenser 42. In other words, the temperature of the condenser 42 is adjusted by the first coolant circulation flow path 51, the first radiator 61, and the first fan 63.

[0029] On the compressor unit A2 side, the compressor 41 and the condenser 42 are incorporated in a refrigerant flow path 72, and a refrigerant flows through the compressor 41 and the condenser 42. An indoor unit 71 is incorporated in the refrigerant flow path 72. In this way, a heating and cooling system is formed by the compressor unit A2 as the outdoor unit A and the indoor unit 71 (see Figs. 1 to 7).

[0030] Next, cooling and heating operations will be described with reference to Fig. 2 to Fig. 7. First, the configuration of the cooling and heating system, the flows of the refrigerant and engine coolant, and the operation of the cooling and heating system will be described. The thick solid lines in Fig. 1 to Fig. 7 indicate the refrigerant flow path (refrigerant piping) 72. The arrows on the refrigerant flow path 72 indicate the direction of refrigerant flow during cooling and heating. The dashed line (chain line) between the refrigerant flow path 72 and TCU (Target Control Unit) 66 indicates the signal line of the TCU (Target Control Unit) 66.

[0031] In the present invention, the selection of either heating or cooling is performed directly by a command from the TCU (total control unit) 66, and the water passage switching valve 53 on the power unit A1 side is operated by the command to switch between the first cooling water circulation passage 51 and the second cooling water circulation passage 52, and the refrigerant passage 72 on the compressor unit A2 side is switched between the heating refrigerant passage 72a and the cooling refrigerant passage 72b by the switching operation of the main refrigerant passage switching valve 73m and the secondary refrigerant passage switching valve 73n. The main refrigerant passage switching valve 73m switches the refrigerant passage 72 between the compressor 41 and the condenser 42, and the secondary refrigerant passage switching valve 73n switches between the heating refrigerant passage 72a and the cooling refrigerant passage 72b in the refrigerant passage 72 on the indoor unit 71 side.

[0032] 16, the main refrigerant passage switching valve 73m and the sub refrigerant passage switching valve 73n have substantially the same structure and include a rotary valve portion 73r therein, which, when rotated left or right, connects the passage switching port 73c to the passage switching port 73a, or the passage switching port 73c to the passage switching port 73b. This rotation is performed by an actuator 73u in response to a signal from a TCU (total control unit) 66.

[0033] These switching positions set by the TCU (total controller) 66 determine whether the heating and cooling system works as a heater or a cooler. A command from the TCU (total controller) 66 is sent to an ECU (engine control unit) 67, which starts the gas engine 1 with the starter 11 using power from the battery 12. The ECU (engine control unit) 67 also controls operating variables such as the ignition timing, air-fuel ratio, and throttle rotation of the gas engine 1. To this end, it adjusts the throttle rotation so that the engine speed of the gas engine 1 is constant, and controls the fuel pressure regulator so that the air-fuel ratio becomes the theoretical air-fuel ratio.

[0034] The heating operation of the gas engine air conditioner of the present invention will be explained with reference to Figures 2 to 4. First, although it depends on the region, in a typical building, the temperature difference between the inside and outside air is larger in winter than in summer. Therefore, it is desirable to improve the heating performance. The present invention is characterized in that it regenerates a part of the thermal energy radiated into the cooling water of the gas engine 1 or the housing.

[0035] First, the water passage switching valve 53 is switched to flow the cooling water passage to the first cooling water circulation passage 51 by a command from the TCU (total control unit) 66 (see FIG. 2). The refrigerant passage 72 between the main compressor 41 and the condenser 42 is switched to a passage corresponding to heating by the main refrigerant passage switching valve 73m, and the heating refrigerant passage 72a is selected by the sub refrigerant passage switching valve 73n, and the refrigerant flows through the heating refrigerant passage 72a and circulates through the refrigerant passage 72 (see FIG. 2 to FIG. 4). The cooling water of the gas engine 1 flows through the first cooling water circulation passage 51, passes through the radiator core 61a of the first radiator 61, dissipates heat into the atmosphere, is sucked by the cooling water pump 13, and is returned to the water jacket of the gas engine 1.

[0036] The power of the gas engine 1 drives the DC generator 2 via a coupling 14. Electric power generated by the DC generator 2 is supplied to the motor 3 through a controller 35 that controls the output of the motor 3 (see FIG. 17(A)). In addition, surplus power from the DC generator 2 due to the output of the gas engine 1 can be supplied to the outside as an AC power source. Specifically, an inverter 65 is connected to the DC generator 2, and the power is supplied to the motor 3 and at the same time, the inverter 65 converts the power into a predetermined power (e.g., 100V, 50Hz) and supplies it to the outside as an AC power source (see FIGS. 1 to 8, etc.).

[0037] A specific example of the controller 35 is a type that controls the current at the inlet or outlet of the motor 3. In this specific example, a large current transistor 35t is used on the inlet or outlet side of the motor 3. FIG. 17(B) shows inlet side control, where the controller 35 is provided on the inlet side of the motor 3. FIG. 17(C) shows outlet side control, where the controller 35 is provided on the outlet side of the motor 3.

[0038] When the output of the motor 3 is increased by the inlet side control, a command is sent from the TCU (total controller) 66 to the controller 35, which commands an increase in the current flowing from point b (base) to point e (emitter) of the controller 35. This significantly increases the current flowing through point c (collector), point b (base), and point e (emitter) of the transistor 35t, increasing the output of the motor 3 and increasing the heating or cooling capacity. The outlet side control has a function substantially equivalent to the inlet side control, so please refer to the inlet side control.

[0039] The engine coolant flows through a core 61a of a first radiator 61 in the first coolant circulation passage 51, and dissipates heat in the first radiator 61 (see Figs. 3 and 4). The high-temperature, high-pressure refrigerant gas from the compressor 41 leaves from the top of the compressor 41 on the drawing and returns to the bottom, as shown in Figs. 3 and 4.

[0040] The high-temperature, high-pressure gaseous refrigerant is switched to the heating-time refrigerant flow path 72a, which is in a blocked state, by switching the secondary refrigerant passage switching valve 73n, so that the refrigerant flows through the heating-time refrigerant flow path 72a. At this time, the refrigerant cannot pass through the cooling-time refrigerant flow path 72b of the refrigerant flow path 72. In the heating-time refrigerant flow path 72a, as shown in Figures 2 to 4, the refrigerant flows as indicated by the arrows in the refrigerant flow path 72, passes through the secondary refrigerant passage switching valve 73n, passes through the core 71a of each indoor unit 71, and releases heat into the room (see Figures 2 and 3).

[0041] At this time, the refrigerant has high gas temperature and pressure until it reaches each expansion valve 71b, and the temperature and pressure drop after passing through the expansion valve 71b, and naturally the temperature becomes lower than the outside air temperature. Then, as shown by the arrow, the refrigerant passes through the refrigerant flow path 72 and enters the suction port (lower side) of the condenser 42. Here, it receives heat and is sucked from the lower side of the compressor 41 via the main refrigerant passage switching valve 73m. The refrigerant is also sucked from the lower side of the compressor 41 during cooling.

[0042] Here, the first fan 63 rotates in a direction to suck outside air into the general housing 9 in response to a command from the TCU (general control unit) 66 (see Figs. 2 to 4). The air that enters from the outside of the general housing 9 passes through the radiator core 61a of the first radiator 61 as passing air, and the heated passing air passes through the condenser 42 to heat the condenser 42, so that the refrigerant in the condenser 42 can be given a larger amount of heat than when it is overheated only by the outside air (see Figs. 2 and 3). The refrigerant heated in the condenser 42 passes through the main refrigerant passage switching valve 73m and flows back to the suction (inlet) side of the compressor 41. The refrigerant is compressed by the compressor 41 to reach a higher temperature and exert a heating effect, and as described later, if the temperature of the refrigerant gas that flows back to the suction side of the compressor 41 becomes higher, the heating performance will be further improved.

[0043] Furthermore, by rotating the second fan 64 on the power unit A1 side in a direction that blows and discharges the passing air from the inside to the outside of the overall housing 9, the amount of air passing through the condenser 42 together with the first fan 63 is further increased, so that the heating effect is further increased (see FIG. 10(B)). During heating, as described above, the water passage switching valve 53 switches so that the entire amount of engine cooling water flows through the radiator core 61a of the first radiator 61, and the radiator core 62a of the second radiator 62 is not functioning. The passing air of the first fan 63 and the second fan 64 does not interfere with the cooling of the gas engine 1.

[0044] Here, it will be explained that increasing the refrigerant gas temperature on the inlet side of the compressor 41 contributes to an increase in the temperature on the outlet side. According to the laws of thermodynamics, when the compressor 41 compresses gas with a volume Vin on the inlet side to Vout (Vin / Vout), if the gas temperature before compression (inlet) is TinK (Kelvin) and the temperature after compression (outlet) is ToutK, then the following holds: TIFF2025023258000002.tif10156

[0045] In the case of adiabatic compression, the value "n" is sometimes referred to as the letter "κ (kappa)", and is a unique value for each gas. For example, the value of helium, a monoatomic molecule, is 1.66, while the value of air, a mixture of diatomic molecules, is 1.4. The greater the number of atoms that make up the molecule, the smaller the value becomes. In the case of isothermal compression, n = 1, regardless of the type of gas. In the following explanation, n for refrigerant gas is assumed to be 1.07.

[0046] Assume that the volume is compressed to 1 / 20 by the compressor 41. Let Tin be 5°C (278K), which is close to the limit at which the heat pump can operate, and compare it with the outlet temperature Tout when heated to 30°C (303K) as in the present invention.

[0047] TIFF2025023258000003.tif20156

[0048] TIFF2025023258000004.tif20156As you can see, the temperature of the heat source that can be used for heating differs by 32°C. The higher the Vin / Vout ratio, the greater this difference becomes.

[0049] Next, the cooling operation will be described with reference to Figures 5 to 7. During cooling, the second cooling water circulation flow path 52 is selected by the water path switching valve 53, and cooling water does not flow through the first cooling water circulation flow path 51. In other words, when the second cooling water circulation flow path 52 is selected by the water path switching valve 53 during cooling, the cooling water flows inside and around the gas engine 1 and serves only to cool the gas engine 1.

[0050] In addition, the refrigerant flow path 72 between the main compressor 41 and the condenser 42 is switched to a flow path corresponding to cooling by the main refrigerant passage switching valve 73m, and the cooling refrigerant flow path 72b is selected by the sub refrigerant passage switching valve 73n, and the refrigerant flows through the cooling refrigerant flow path 72b and circulates through the refrigerant flow path 72 (see Figs. 5 to 7). The compressor 41 driven by the motor 3 compresses the gaseous refrigerant (which may contain a small amount of liquid) and the refrigerant becomes a high-temperature gas, and enters the condenser 42 through the main refrigerant passage switching valve 73m in the switching position shown in Figs. 5 to 7. Here, the refrigerant releases heat and its temperature drops to liquid (including gaseous), and when it passes through the expansion valve 71b of the indoor unit 71, it vaporizes and expands all at once, causing its temperature to drop significantly, and the core 71a takes heat from the indoor air and lowers the air temperature.

[0051] The gaseous refrigerant expanded in the indoor unit 71 returns to the suction side of the compressor 41 through the cooling-time refrigerant flow path 72b selected by the sub-refrigerant passage switching valve 73n (see Figs. 5 to 7). Thus, during cooling, the first cooling water circulation flow path 51 is blocked by the water passage switching valve 53, and the cooling water does not flow through the first cooling water circulation flow path 51. Therefore, the cooling water does not pass through the first radiator 61, and does not warm the condenser 42 and the refrigerant in the condenser 42. In addition, the second fan 64, which can rotate forward and backward, cools the first radiator 61 if it is rotated to suck in outside air, and increases the amount of air passing through the radiator core 61a, which is advantageous for cooling the engine during cooling.

[0052] In Fig. 1(A), Fig. 2 and Fig. 5, the power unit A1 and the compressor unit A2 are housed in one overall housing 9 to form the outdoor unit A. In contrast, there is an embodiment in which the overall housing 9 is divided into two housings, a first housing 91 and a second housing 92 (see Fig. 12). The first housing 91 houses a power supply system including the gas engine 1, the DC generator 2, the TCU (overall controller) 66, the ECU (engine control unit) 67, the second cooling water circulation flow path 52, the second radiator 62 and the second fan 64 that constitute the power unit A1. The second housing 92 houses the motor 3, the controller 35, the compressor 41, the condenser 42, the first radiator 61 and the first fan 63 that constitute the compressor unit A2. The only things connecting the first housing 91 and the second housing 92 are the first coolant circulation flow path 51, a signal line, and a cable for transmitting the electricity generated by the DC generator 2, and the air conditioning refrigerant flow path (refrigerant piping) 72 is provided only in the second housing 92.

[0053] In this way, by separating the power unit A1 and the compressor unit A2 and storing them in the first housing 91 and the second housing 92, if the gas engine 1 on the power unit A1 side has spare power and ample electric power, it is possible to operate one power unit A1 stored in the first housing 91 and multiple compressor units A2 stored in the second housing 92 in parallel (see FIG. 13). This type of configuration has the following advantages.

[0054] That is, it can be installed very efficiently as a heating and cooling equipment for a building with many rooms or a multi-story building. The first housing 91 having the power unit A1 is used as the main unit, and this single power unit A1 is installed indoors such as the basement of the main power room or the machine room of the building (see FIG. 13). A plurality of second housings 92 having the compressor unit A2 are provided and arranged in parallel on each floor. The compressor units A2 integrated into these second housings 92 are installed on each floor, and each compressor unit A2 is responsible for a plurality of indoor units installed on each floor, so that the power generated by the power unit A1 integrated into the first housing 91 can be used very effectively, and a low-cost heating and cooling equipment can be provided. The first housing 91 may be installed outdoors of the building.

[0055] Power is supplied to the outside by an inverter 65 of the power unit A1 of the first housing 91 (see FIG. 1). Specifically, a DC / AC (direct current / alternating current) inverter is used as the inverter 65. The inverter is also sometimes called a converter. The first housing 91 housing the power unit A1 is installed in a basement or on the roof, and a second housing 92 housing the compressor unit A2 is provided on each floor or building, thereby shortening the refrigerant flow path (refrigerant piping) 72 from each second housing 92 to each indoor unit 71, and the exchange of heat between the refrigerant and the atmosphere in the refrigerant flow path (refrigerant piping) 72 can be reduced, improving air conditioning performance.

[0056] Next, a specific example of the relationship between the thermal efficiency of a gas engine cooling and heating device and the overall thermal efficiency of a heat pump system in the present invention will be described. The calculations are based on the assumption that the output of the gas engine 1 is 20 kW, the surplus power (power supplied to the outside) is 5 kW, and the power generation efficiency and inverter efficiency are each 95%. Here, for simplicity of explanation, the power consumed by the electric fan and control inside the housing, which is just under 1 kW, is included in this 5 kW.

[0057] If the engine output is 20kw, 5.54kw (5kw×1 / 0.95×1 / 0.95...external power supply) 14.46kw (20kw - 5.54kw)···Heat pump power.

[0058] Of this power, the power that can be consumed by the DC motor 3 is 14.46kW x 0.95 = 13.74kW, assuming the efficiency of the motor controller 35 is 95%. Because waste heat is recovered, a COP (coefficient of performance) of 5.5 or more can be ensured even in heating mode. The thermal energy available for heating obtained from the 13.74 kW of electricity mentioned above is as follows: 13.74 x 5.5 = 75.57 kW.

[0059] Therefore, (heating thermal energy) + (external power supply) - 80.57kW On the other hand, if the thermal efficiency of the engine is ηE, the energy Qf of the fuel is, Qf=20kw / ηE. Therefore, the total thermal efficiency ηT is: ηT=80.57kw / (20kW / ηE)≒4ηE···(1) It becomes.

[0060] By pursuing the utmost in speeding up combustion and minimizing cooling losses, and making full use of the inertial intake and exhaust phenomenon, a thermal efficiency of 44% or more can be achieved even when operating a gas engine 1 at the theoretical air-to-air ratio to activate a three-way catalyst 16k. Furthermore, by keeping the normal engine speed below 2400 rpm, friction losses can be reduced to 7% or less, and the engine's mechanical efficiency can be increased to 93% or more. In this way, the thermal efficiency of the engine is: ηE=44×0.93≧40.92% (2) It becomes.

[0061] From equations (1) and (2), ηT≧4×0.4=1.6 That is, the overall thermal efficiency is 160%. If all of the power generated by the DC generator 2 were used to drive the compressor 41, this system could achieve an overall thermal efficiency of 200% or more.

[0062] As mentioned above, even when operating at the theoretical air-fuel ratio to activate the three-way catalyst 16k, in order to achieve a higher indicated thermal efficiency than lean burn or pre-chamber types, the surface area of ​​the combustion chamber is reduced as shown in Figure 15, and ignition is performed simultaneously from two points to shorten the flame propagation distance. Furthermore, the reflection of the flame raises the gas temperature in the unburned parts, increasing the flame propagation speed.

[0063] In the gas engine 1, the combustion chamber is point-symmetrical with respect to the center of the cylinder, the intake valve 16a and the exhaust valve 16b have the same (almost the same) seat diameter, and the two spark plugs 16c are also arranged symmetrically. Their centers are on a circumference that is half the cylinder diameter. Furthermore, the extensions of these centerlines intersect at the 0 point on the centerline of the cylinder. The combustion chamber is a thin spherical shell with a radius R centered on this 0 point, and the ignition point and the seat parts of the intake valve 16a and exhaust valve 16b are approximately aligned along the spherical shell.

[0064] The pressure of the gas fuel supplied to the mixer 16f is adjusted by a fuel pressure regulator 16g so that the air-fuel ratio becomes the theoretical air-fuel ratio based on a signal from an O2 sensor 16d installed in the exhaust system. The engine speed sensor 16h installed near the flywheel 15 detects the rotation speed of the crankshaft 16s, and when the load on the gas engine 1 increases and the rotation speed drops, the throttle opening is adjusted to a specified rotation speed (for example, 2200 rpm) (see Figure 15). If the rotation speed is high, the throttle is moved in the closing direction.

[0065] In order to reduce friction loss, the stroke is not long, but is set to the cylinder diameter or slightly longer as shown in Figure 15, and a high compression ratio (12 or more) is not pursued only by increasing the stroke, but is realized with the compact combustion chamber mentioned above. The engine speed, air-fuel ratio, ignition timing, engine start and stop, etc. are all controlled by the ECU (engine control unit) 67. Fluctuations in torque caused by each stroke of intake, compression, expansion, and exhaust cause fluctuations in the engine speed. Even slight fluctuations in this speed (for example, 1 / 50) hinder power generation efficiency. Therefore, a coupling 14 is placed between the flywheel 15 and the DC generator 2 to smooth out vibrations in the rotational direction.

[0066] Next, a structural example of the coupling 14 that connects the gas engine 1 and the DC generator 2 is shown. As shown in Fig. 14, the coupling 14 is composed of a buffer member 14a, two flanges 14b, and a pin 14p. The flange 14b is a substantially Y-shaped member (see Fig. 14(C)), and in its center, a spline hub 14h is formed as a female spline at intervals of 120 degrees along the circumferential direction. In addition, three arm-shaped pieces 14c are arranged radially with the spline hub 14h as the diameter center, and a connecting hole 14d through which the pin 14p passes is formed at the tip of the arm-shaped piece 14c.

[0067] The buffer member 14a has a substantially cylindrical shape and is made of an elastic material, such as rubber or synthetic resin (see FIG. 14(D)). A through hole 14f is formed in the center of the diameter of the buffer member 14a along the axial direction, and the spline hub 14h of the flange 14b is loosely inserted into the through hole 14f. Here, loose insertion means that the spline hub 14h is inserted into the through hole 14f with a gap, and the spline hub 14h is movable in the through hole 14f with some play. In addition, six tubular sleeves 14e are arranged at equal intervals (60 degrees) in the buffer member 14a near the outer periphery and along the axial direction. The pin 14p is inserted in a press-fit state into the sleeve 14e.

[0068] The flanges 14b are disposed at both axial ends of the buffer member 14a so as to face each other. The arm pieces 14c of the flanges 14b are not in phase with each other and are disposed offset by 60 degrees from each other. Three pins 14p are disposed at 120-degree intervals near the outer periphery of the spline hub 14h of each flange 14b, and the pins 14p are inserted into connecting holes 14d at the ends of the arm pieces 14c and into sleeves 14e provided in the buffer member 14a, thereby connecting the buffer member 14a and the flanges 14b. In this way, the coupling 14 is used as a flange joint that can be elastically deflected along the axial direction.

[0069] On the other hand, the adapter 15a having a male spline 15s at its center is fixed by a bolt to the flywheel 15 mounted on the gas engine 1. The DC generator 2 is also provided with a male spline 2s. The spline 15s of the flywheel 15 and the spline 2s of the DC generator 2 are inserted into the spline hubs 14h on both axial sides of the coupling 14, so that the gas engine 1 and the DC generator 2 can transmit rotational drive. The torque of the gas engine 1 is smoothed and transmitted from the spline 2s on the DC generator 2 side to the DC generator 2 via the buffer member 14a of the coupling 14. In the present invention, the gaseous refrigerant (including a small part of the liquid state) that has just been pressurized by the compressor 41 is directly circulated without using an intermediate refrigerant such as water.

[0070] In the present invention, there is an embodiment in which the second fan 64 that sends the passing air to the second radiator 62 is configured to be able to change the direction of the passing air to the second radiator 62 (see FIG. 9). In this embodiment, the propeller of the second fan 64 is rotated forward and backward, so that the direction of the passing air to the second radiator 62 can be changed between forward and reverse rotation. This makes it possible to prevent the power unit A from overheating and damaging the device during cooling in the summer.

[0071] In particular, the following problems are likely to occur in the summer. First, engine output decreases due to a decrease in the density of the intake air. Secondly, in the case of a spark ignition engine, knocking may occur, which may damage the engine. Secondly, overheating of the generator reduces the power generation efficiency and the inverter conversion efficiency. The above problems can be solved by controlling the air flow inside the overall housing 9 by rotating the second fan 64, which can rotate in both forward and reverse directions, in the forward or reverse direction depending on the situation, as described above, and the environment inside the overall housing 9 can be maintained in a good state (see FIG. 8).

[0072] First, the temperature of the housing (the overall housing 9, the first housing 91 or the second housing 92) is detected, and when it reaches 60°C, the second fan 64 is rotated from forward to maximum reverse rotation in response to a command from a TCU (overall control unit) 66, and outside air is introduced into the housing to cool it down. The second fan 64 has a plurality of blades 64, each of which has a flat blade center portion 64a in the middle along the rotation direction, and has blade ends 64b, 64c at both ends of the terminals at both ends of the rotation direction of the blade center portion 64a, and the attack angles α+β of both blade ends 64b, 64c are set to be the same and are set to an angle α smaller than the attack angle of the blade center portion 64a.

[0073] The second fan 64, which can rotate in both forward and reverse directions and is used in the gas engine air conditioner of the present invention, will now be described. The second fan 64 is driven by an electric motor in order to easily rotate in both forward and reverse directions without using gears or the like. Conventional fan blades have camber (for example, arc-shaped) to increase efficiency. When the fan is rotated clockwise (forward direction) as viewed from the front, efficiency is improved compared to a flat fan like a fan. However, there is a problem in that the volume of air is reduced when rotating in reverse.

[0074] In contrast, in the second fan 64 shown in FIG. 9, when flat plates are combined, the attack angle is the same in both forward and reverse rotation, and the same air volume can be obtained regardless of forward and reverse rotation, which is optimal for the present invention. Next, the operation will be explained. In the second fan 64, the blade has a blade center 64a and blade ends 64b and 64c. The central blade center 64a has the same attack angle of α+β in both forward and reverse rotation. In the case of forward rotation, the blade end 64c becomes the leading edge, and the attack angle of this part is angle α, which is smaller by β than that of the blade center 64a, and this softens the collision with the air. Also, in FIG. 9, reference numeral 64d denotes a blade attachment portion, and 64e denotes a motor that rotates the second fan 64.

[0075] Another embodiment of the second fan 64 shown in FIG. 10 has a four-blade structure similar to that shown in FIG. 9, and the attack angle is the same in both forward and reverse rotation, so that the same air volume is obtained regardless of forward and reverse rotation. The blade center 64a, blade end 64b, 64c, and motor 64e are the same as those shown in FIG. 9, and the blade attachment part 64d is cylindrical. In particular, the attack angle α+β is about 30 degrees, and the angle α is about 25 degrees. This shape is considered to be optimal. As shown in FIG. 11(D), a three-blade structure also produces the same effect as a four-blade structure.

[0076] Also, the blade end 64b becomes the trailing edge, but the angle is smaller than that of the blade center 64a, reducing the vortex generated on the back surface. By folding in three stages in this way, it becomes closer to a cambered blade blade than a fan-shaped blade. In the case of reverse rotation, the blade end 64b becomes the leading edge and the blade end 64c becomes the trailing edge, and the shape is the same as in the case of forward rotation, so that in the case of forward rotation, it does not reach the cambered blade, but the same air volume can be secured in both forward and reverse rotation. In the second fan 64, the direction in which the second fan 64 rotates so that the passing air is introduced from the outside of the overall housing 9 to the inside of the overall housing 9 is defined as the forward rotation direction. In the second fan 64, the direction in which the second fan 64 rotates so that the passing air is introduced from the inside of the overall housing 9 to the outside of the overall housing 9 is defined as the reverse rotation direction.

[0077] The rotation directions of the first fan 63 and the second fan 64 will be described during cooling, overheating, and heating. During cooling, overheating, and heating, the first fan 63 always rotates forward and operates to draw in passing air from the outside of the general housing 9 to the inside of the general housing 9. The second fan 64 has a structure that can rotate forward and backward. During cooling, as shown in FIG. 10(A), passing air flows in one direction inside the general housing 9 from the first radiator 61 side to the second radiator 62 side. The second fan 64 rotates backward and acts to draw in passing air from the inside of the general housing 9 to the outside of the general housing 9. Since it is during cooling, cooling water is not circulating through the first cooling water circulation passage 51 and the first radiator 61.

[0078] During overheating, as shown in Fig. 8(B), strong ventilation is required inside the overall housing 9. Therefore, the first fan 63 and the second fan 64 are used to introduce airflow into the overall housing 9 for ventilation. Both the first fan 63 and the second fan 64 rotate strongly in the forward direction. At this time, no cooling water is circulating through the first cooling water circulation passage 51 and the first radiator 61.

[0079] During heating, as shown in Fig. 8(C), a strong passing wind is made to flow from the first radiator 61 side to the second radiator 62 side inside the overall housing 9. The second fan 64 is rotated in the reverse direction or stopped. Since it is during heating, the cooling water is circulating through the first cooling water circulation passage 51 and the first radiator 61.

[0080] In the above description, the motor 3 has been described as a DC motor. An embodiment in which an AC motor 3A is used as the motor 3 will be described with reference to Figs. 18 to 20. In this embodiment, an AC generator 2A is used instead of the DC generator 2, and the motor 3 is an AC motor 3A as described above (see Figs. 16 to 18). The configuration and arrangement of the gas engine 1, the first cooling water circulation flow path 51, the second cooling water circulation flow path 52, the compressor 41, the condenser 42, and other devices, and the operation of the cooling water and the refrigerant during heating and cooling are the same as those of the embodiment using the DC generator 2 and the DC motor 3 described above, so please refer to Figs. 2 to 7. In this embodiment, the AC generator 2A sends an AC current to the AC controller 35A by the gas engine 1.

[0081] The AC controller 35A is different from the one corresponding to the DC motor 3, and the one corresponding to the AC motor 3A will be described. The controller 35A includes a rectifier 35a. The rectifier 35a has a function of adjusting the fundamental frequency to be suitable for the AC motor 3A when sending a current from the AC generator 2A to the AC motor 3A (see FIG. 20).

[0082] Furthermore, this fundamental frequency needs to be amplified in order to drive the AC motor 3A. Therefore, the AC current of the fundamental frequency is sent to a large-capacity transistor 35t, and an AC signal that amplifies the AC current to a driving frequency required to operate the AC motor 3A is sent to this transistor 35t by a command from a TCU (total control unit) 66 (see FIG. 20(B)).

[0083] This transistor 35t amplifies the fundamental frequency generated by the rectifier to a drive frequency required for driving and rotating the AC motor 3A, and drives the AC motor 3A. By instructing the TCU (total control unit) 66, the rotational speed of the AC motor 3A is increased by a drive frequency that is amplified by a large amount relative to the fundamental frequency, thereby increasing the cooling and heating capacity.

[0084] Also, by reducing the amplification amount of the fundamental frequency to set the drive frequency according to a command from the TCU (total control unit) 66, it is possible to reduce the heating / cooling capacity and save energy. Specifically, when increasing the output of the AC motor 3A, a command is issued from the TCU (total control unit) 66 to the controller 35, which commands an increase in the current flowing from point b (base) to point e (emitter) of the controller 35. This significantly increases the current flowing through point c (collector), point b (base), and point e (emitter) of the transistor 35t, increasing the output of the AC motor 3A and increasing the heating or cooling capacity.

[0085] In an embodiment of a cooling and heating device using an AC generator 2A and an AC motor 3A, an AC-AC inverter is used as the inverter 65 (see FIG. 20(A)). The inverter 65 (AC-AC inverter) has the role of stabilizing the high-voltage AC current generated by the AC generator 2A and adjusting it so that it can be used as a general AC power source.

[0086] 19 shows an embodiment in which an AC generator 2A is used as the generator, and a DC motor is used as the motor 3. In this embodiment, AC power generated by the AC generator 2A is converted to DC by a controller 35, and electricity is sent to the DC motor 3. [Explanation of symbols]

[0087] A1...Power unit, A2...Compressor unit, 1...Gas engine, 2...DC generator, 2A...AC generator, 3...Motor, 3A...AC motor, 41...compressor, 42...condenser, 51...first cooling water circulation flow path, 52: second cooling water circulation passage; 53: water passage switching valve; 61: first radiator; 62...second radiator, 63...first fan, 64...second fan, 66...TCU (total control unit), 67...ECU (engine control unit), 9... overall housing, 91... first housing, 92... second housing, 64a... center of blade, 64b, 64c…feather tip, α+β…attack angle.

Claims

1. a gas engine air conditioner including an overall housing having a gas engine, a first cooling water circulation flow path and a second cooling water circulation flow path through which cooling water for the gas engine circulates, a first radiator provided in the first cooling water circulation flow path, a second radiator provided in the second cooling water circulation flow path, a water path switching valve for circulating the cooling water to either the first cooling water circulation flow path or the second cooling water circulation flow path, a direct current generator driven by the gas engine, a motor operated by the direct current generator, a compressor driven by the motor for compressing a refrigerant, a condenser for heat exchange with the refrigerant, a first fan which rotates only in the forward direction and provides a passing airflow to the first radiator, and a second fan which rotates in the forward and reverse directions and also provides a passing airflow to the second radiator, During cooling and heating, the first fan rotates in a forward direction and the second fan rotates in a reverse direction, so that passing air flows in one direction from the first radiator side to the second radiator side, The DC generator is configured to supply surplus power to an external device as an AC power source, a gas engine heating and cooling device configured such that, in the event of overheating, cooling water is caused to flow into the second cooling water circulation flow path via the water path switching valve, and the first fan rotating in the forward direction and the second fan rotating in the forward direction introduce passing air into the overall housing to ventilate, the second fan has a plurality of blades, each of which has a flat blade center portion midway along the direction of rotation and has blade end portions at both ends of the blade center portion in the rotation direction, the angle of attack of the blade center portion of the second fan being α+β in the forward and reverse rotations, and both blade end portions of the blade are bent at the same angle α, and the second fan can ensure the same air volume in both the forward and reverse rotations.

2. 2. The gas engine air conditioner according to claim 1, wherein the number of blades of the second fan is four.

3. 2. The gas engine air conditioner according to claim 1, wherein the number of blades of the second fan is three.

4. 3. The gas engine air conditioner according to claim 1, wherein the angle of attack of the blades of the second fan (α+β) is 30 degrees, and the angle of attack (α) is 25 degrees.

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