COMBINATION DEVICE

Abstract

One purpose of the present invention is to provide a combination device that contributes to the miniaturization of vehicle air conditioning systems and the like, and that can ensure the cooling capacity (heat dissipation) of a switching element that converts direct current to alternating current. The combination device (1) with a refrigerant compression function and a heating medium function comprises: a first housing (2A) that accommodates a compression mechanism (3) for compressing a refrigerant and an electric motor (4) for driving the compression mechanism (3) in series; a second housing (2B) that accommodates the electric heater (5) for heating a heating medium; and a third housing (2C) that accommodates the motor drive circuit (20) and the heater control circuit (30).The first power switching elements (Q1 to Q6) of the motor drive circuit (20) are arranged in the third housing (2C) such that they can be cooled by a refrigerant flowing from the refrigerant inlet (8) into the first housing (2A) and by a heating medium flowing from the heating medium inlet (10) into the second housing (2B).

Description

TECHNICAL FIELD

[0001] The invention relates to a combination device with a refrigerant compression function and a heating medium heating function. STATE OF THE ART

[0002] Patent Document 1 discloses a vehicle air conditioner applicable to vehicles such as hybrid vehicles and electric vehicles. The vehicle air conditioner disclosed in Patent Document 1 includes an electric compressor that compresses a refrigerant, a radiator that heats the air supplied to the passenger compartment by radiating the refrigerant discharged from the electric compressor, an expansion valve that expands the radiated refrigerant under reduced pressure, and a refrigerant circuit including a heat exchanger similar to an evaporator that performs heat exchange between the refrigerant expanded under reduced pressure and the outside air.The vehicle air conditioner disclosed in Patent Document 1 further includes: an electric heater for heating a heating medium to assist the heating in the passenger compartment by the radiator, and a heating medium-air heat exchanger that heats the air supplied to the passenger compartment with the heated heating medium. LIST OF REFERENCE DOCUMENTSPATENT DOCUMENTS

[0003] Patent Document 1: JP 2014-213765 A SUMMARY OF THE INVENTIONOBJECTS OF THE INVENTION

[0004] The vehicle air conditioner disclosed in Patent Document 1 can supplement the lacking heating capacity of the radiator. However, in the vehicle air conditioner disclosed in Patent Document 1, the electric compressor and the electric heater for heating the heating medium are provided separately. Therefore, the entire device is enlarged, and there is room for improvement in terms of installation space, etc.

[0005] It is a purpose of the present invention to provide a combination device that contributes to the downsizing of vehicle air conditioners and the like and that can ensure the cooling performance (heat radiation conduction) of a switching element that converts DC voltage into AC voltage. SOLUTION OF THE TASKS

[0006] According to one aspect of the present invention, a combination device with a refrigerant compression function and a heating medium heating function is provided. The combination device includes a compression mechanism for compressing a refrigerant, an electric motor for driving the compression mechanism, a compressor housing that houses the compression mechanism and the electric motor in series inside, and has a refrigerant inlet that admits the refrigerant compressed by the compression mechanism into the interior and a refrigerant outlet that discharges the refrigerant compressed by the compression mechanism to the outside, an electric heater for heating a heating medium, a heater housing that houses the electric heater inside, and has a heating medium inlet that admits the heating medium heated by the electric heater into the interior, and a heating medium outlet.which discharges the heating medium heated by the electric heater to the outside, a motor drive circuit for controlling the electric motor, a heater control circuit for controlling the electric heater, and a circuit housing that houses the motor drive circuit and the heater control circuit inside, wherein the compressor housing, the heater housing, and the circuit housing are integrally connected to each other. The motor drive circuit has switching elements that convert DC voltage to AC voltage, and the switching elements of the motor drive circuit in the circuit housing are arranged such that they can be cooled by a refrigerant flowing into the compressor housing and also by a heating medium flowing into the heater housing. EFFECTS OF THE INVENTION

[0007] According to the present invention, it is possible to provide a combination device that contributes to the downsizing of vehicle air conditioners and the like and that can ensure the cooling performance (heat radiation conduction) of a switching element that converts DC voltage into AC voltage. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a front view of the combination device according to an embodiment. Fig. 2 shows a right side view of the combination device according to an embodiment. Fig. 3 shows a plan view of the combination device according to an embodiment. Fig. Figure 4 shows a partially schematic sectional view of the combination device according to an embodiment, which corresponds to the AA sectional view of Fig. 2 corresponds. Fig. 5 is a view showing a configuration example of the essential part of a motor drive circuit of the combination device according to an embodiment. Fig. 6 is a view showing a configuration example of the essential part of a heater control circuit of the combination device according to an embodiment. Fig. Figure 7 shows a partially schematic sectional view of the combination device according to an embodiment, which corresponds to the BB sectional view of Fig. 3 corresponds. Fig. 8 is a block diagram showing the schematic configuration of a control system of the combining device according to an embodiment. Fig. 9 is a flowchart showing an example of the operation control of the refrigerant compression function. Fig. 10 is a flowchart showing an example of the operation control of the refrigerant compression function. Fig. 11 shows a flowchart showing an example of the operation control of the heating medium heating function. DESCRIPTION OF THE EMBODIMENTS

[0008] In the following, the embodiment of the present invention will be explained with reference to the accompanying drawings.

[0009] Fig. 1 to 4 show a schematic design of a combination device 1 according to an embodiment of the present invention. Fig. 1 is a front view of the combination device 1 according to an embodiment, Fig. 2 is a right side view of the combination device 1 according to an embodiment, Fig. 3 is a plan view of the combination device 1 according to an embodiment, and Fig. 4 is a partially schematic sectional view of the combination device according to an embodiment, corresponding to the AA sectional view of Fig. 2 corresponds.

[0010] The combination device 1 of the embodiment has a refrigerant compression function that compresses a refrigerant and a heating medium heating function that heats a heating medium other than the refrigerant. That is, the combination device 1 has a configuration that integrates a refrigerant compressor and a heating medium heating device.

[0011] The combination device 1 can be applied to the vehicle air conditioning systems described above. That is, the combination device 1 can be installed and used in a refrigerant circuit in which the refrigerant circulates, and in a heating circuit in which the heating medium circulates by means of a pump part. The pump part can mainly consist of an electric pump. However, the pump part is not limited to this and can be configured to circulate the heating medium in the heating circuit. For example, a refrigerant compression function part of the combination device 1 can be configured to be integrated into the refrigerant circuit, compress refrigerant that has passed through an expansion valve and an evaporator (or a corresponding heat exchanger), and supply the compressed refrigerant to a radiator (refrigerant-to-air heat exchanger) for heating air supplied to the passenger compartment.A heating medium heating function part of the combination device 1 can further be configured to be integrated into the heating medium circuit, heat a heating medium that has passed through a heating medium-to-air heat exchanger for heating air supplied to the passenger compartment, and supply the heated heating medium to the heating medium-to-air heat exchanger. The refrigerant and the heating medium can be arbitrarily selected, and for example, a gaseous refrigerant can be used as the refrigerant and a liquid as the heating medium. Although there is no limitation, water (including water mixed with antifreeze, etc.) is normally used as the heating medium. Therefore, the heating medium heating function can also be referred to as a water heating function.

[0012] On Fig. Referring to Figures 1 to 4, the combination device 1 includes a housing 2. The housing 2 of the combination device 1 includes a first housing 2A, a second housing 2B, a third housing 2C, a first cover 2D, a second cover 2E, and a third cover 2F, which are integrally connected (attached) by screws or other fastening elements not shown.

[0013] The first housing 2A is formed in a substantially cylindrical shape. Inside the first housing 2A, a compression mechanism 3 for compressing the refrigerant and an electric motor 4 for driving the compression mechanism 3 are arranged in series in the axial direction. The compression mechanism 3 may be, but is not limited to, a scroll compression mechanism including a fixed scroll and a movable (swinging) scroll. The output shaft 4a of the electric motor 4 is further connected to the compression mechanism 3 (e.g., the movable (swinging) scroll).

[0014] One of the two opening ends (the lower opening end in Fig. 1 and Fig. 2) of the first housing 2A, i.e., the opening end on the compression mechanism 3 side of the first housing 2A, is closed by the first cover 2D. The first housing 2A, which houses the compression mechanism 3 and the electric motor 4 driving it, may also be referred to as the "compressor housing."

[0015] The second housing 2B is arranged laterally of the first housing 2A. The second housing 2B is formed in a substantially rectangular tubular shape. An electric heater 5 for heating the heating medium is accommodated inside the second housing 2B.

[0016] One of the two opening ends of the second housing 2B (the lower opening end in Fig. 1 and Fig. 2) is closed by the second cover 2E. The second housing 2B, which houses the electric heater 5, can also be referred to as the "heater housing."

[0017] The third housing 2C is formed in the shape of a box with an open top. Inside the third housing 2C, a motor drive circuit 20 that controls the electric motor 4 and a heater control circuit 30 that controls the electric heater 5 are housed. Specifically, a circuit board 6 on which the motor drive circuit 20 and the heater control circuit 30 are mounted is housed inside the third housing 2C.

[0018] A bottom wall 7 of the third housing 2C closes the other opening end (upper opening end in Fig. 1 and Fig. 2) of the first housing 2A, ie, the opening end of the first housing 2A on the side of the electric motor 4 and the other opening end (upper opening end in Fig. 1 and Fig. 2) of the second housing 2B. This separates the interior of the first housing 2A and the interior of the third housing 2C, and separates the interior of the second housing 2B and the interior of the third housing 2C. That is, the bottom wall 7 of the third housing 2C has a first partition 71 separating the interior of the first housing 2A and the interior of the third housing 2C, and a second partition 72 separating the interior of the second housing 2B and the interior of the third housing 2C. The first partition 71 and the second partition 72 are adjacent to each other.

[0019] The top (opening end) of the third housing 2C is closed by the third cover 2F. The third housing 2C, in which the motor drive circuit 20 and the heater control circuit 30 are housed, may also be referred to as a "circuit housing."

[0020] In the combination device 1, the refrigerant compression function (refrigerant compressor) is mainly realized by the compression mechanism 3, the electric motor 4 and the motor drive circuit 20, and the heating medium heating function (heating medium heating device) is mainly realized by the electric heater 5 and the heater control circuit 30.

[0021] A refrigerant inlet 8 is formed in the first housing 2A, through which the refrigerant circulating in the refrigerant cycle enters the interior. The admitted refrigerant is, for example, a refrigerant that has passed through an expansion valve and an evaporator (or a corresponding heat exchanger), i.e., a low-temperature, low-pressure refrigerant. In the present embodiment, the refrigerant inlet 8 is provided at a part of the first housing 2A on the third housing 2C side, i.e., near the first partition 71 separating the interior of the first housing 2A and the interior of the third housing 2C. Preferably, the refrigerant inlet 8 is configured such that the refrigerant circulating in the refrigerant cycle flows into the first housing 2A, so that at least a portion of the refrigerant flows along the first partition 71.

[0022] The refrigerant (at low temperature and low pressure) flowing into the interior of the first housing 2A via the refrigerant inlet 8 flows through the interior of the first housing 2A and is sucked into the compression mechanism 3. The refrigerant sucked into the compression mechanism 3 is compressed by the compression mechanism 3 and discharged from the compression mechanism 3 as a high-temperature and high-pressure refrigerant. The discharged refrigerant (at high temperature and high pressure) flows out from the refrigerant outlet 9 formed in the first housing 2A and is supplied, for example, to the radiator (refrigerant-to-air heat exchanger) described above.

[0023] In the present embodiment, the refrigerant outlet 9 is provided at a part of the first housing 2A on the side of the first cover 2D, that is, in the vertical direction in Fig. 1 and Fig. 2 spaced from the refrigerant inlet 8. Therefore, in the present embodiment, the refrigerant flowing into the first housing 2A from the refrigerant inlet 8 flows from the upper side to the lower side in Fig. 1 and Fig. 2 in the first housing 2A.

[0024] The first partition 71 can be cooled with the refrigerant (at low temperature and low pressure) flowing into the first housing 2A via the refrigerant inlet 8, and the electric motor 4 can be cooled with the refrigerant flowing into the interior of the first housing 2A. The refrigerant inlet 8, the interior of the first housing 2A, and the refrigerant outlet 9 further form part of the refrigerant circuit.

[0025] In the second housing 2B, a heating medium inlet 10 is formed for admitting a heating medium circulating in the heating medium circuit into the interior. The heating medium to be admitted is, for example, a heating medium that has passed through the above-described heating medium-air heat exchanger, i.e., a low-temperature heating medium. In the present embodiment, the heating medium inlet 10 is provided at a part of the second housing 2B on the third housing 2C side, i.e., near the second partition part 72 separating the interior of the second housing 2B and the interior of the third housing 2C, and on the rear side in Fig. 1 (on the right side in Fig. 2). Preferably, the heating medium inlet 10 is configured such that the heating medium circulating in the heating medium circuit flows into the second housing 2B, so that at least a portion of the heating medium flows along the second separating part 72.

[0026] The heating medium (at a low temperature) flowing into the interior of the second housing 2B via the heating medium inlet 10 flows through the interior of the second housing 2B, where it is heated by the electric heater 5 and heats up. The heated heating medium flows out from the heating medium outlet 11 formed in the second housing 2B and is fed, for example, to the heating medium-to-air heat exchanger described above.

[0027] In the present embodiment, the heating medium outlet 11 is located near the second partition part 72 which separates the inside of the second casing 2B and the inside of the third casing 2C, and on the front side in Fig. 1 (on the left side in Fig. 2). Therefore, in the present embodiment, the heating medium flowing from the heating medium inlet 10 into the second housing 2B flows inside the second housing 2B along the second partition part 72, from the right side to the left side in Fig. 2 and Fig. 4.

[0028] The second separating part 72 can be cooled by the heating medium (at low temperature) flowing into the second housing 2B via the heating medium inlet 10. The heating medium inlet 10, the interior of the second housing 2B, and the heating medium outlet 11 form part of the heating medium circuit.

[0029] Although not shown in the drawings, the supply lines from the motor drive circuit 20 to the electric motor 4 and from the heater control circuit 30 to the electric heater 5 extend here, each in an airtight or liquid-tight manner, through the bottom wall 7 of the third housing 2C.

[0030] Next, the motor drive circuit 20 that controls (drives) the electric motor 4 and the heater control circuit 30 that controls the electric heater 5 will be explained with reference to the Fig. 5 and Fig. 6 explained.

[0031] Fig. 5 is a view showing a configuration example of the essential part of the motor drive circuit 20. In the present embodiment, the motor drive circuit 20 is configured to control (drive) the electric motor 4 by converting a DC voltage from an external power source into a three-phase AC voltage and supplying it to the electric motor 4. The motor drive circuit 20 includes a smoothing part 21, a first power module 22, and a first driver circuit 23.

[0032] The smoothing part 21 is connected between the power line and the ground line of the external power source and smooths the DC voltage of the external power source. Although not particularly limited, the smoothing part 21 can be formed, for example, from a plurality of electrolytic capacitors.

[0033] The first power module 22 includes six power switching elements (hereinafter referred to as "first power switching elements") Q1 to Q6 and six diodes D1 to D6. Although not particularly limited, the first power switching elements Q1 to Q6 may be IGBTs (Insulated Gate Bipolar Transistors). The first power module 22 converts the DC voltage of the external power source, which is smoothed by the smoothing part 21, into a three-phase AC voltage through PWM control of the first power switching elements Q1 to Q6 and supplies it to the electric motor 4.

[0034] Specifically, the first power module 22 has a U-phase arm, a V-phase arm, and a W-phase arm provided in parallel to each other between the power line and the ground line of the external power source.

[0035] In the U-phase arm, two first power switching elements Q1, Q2 are connected in series, and the diodes D1, D2 are connected in reverse parallel with each first power switching element Q1, Q2.

[0036] In the V-phase arm, two first power switching elements Q3, Q4 are connected in series, and the diodes D3, D4 are connected in reverse parallel with each first power switching element Q3, Q4.

[0037] In the W-phase arm, two first power switching elements Q5, Q6 are connected in series, and the diodes D5, D6 are connected in reverse parallel with each first power switching element Q5, Q6.

[0038] The intermediate points of the U-, V-, and W-phase arms are further connected to the other ends of the U-, V-, and W-phase coils of the electric motor 4, which are star-connected at their respective ends. That is, the intermediate point of the power switching elements Q1, Q2 of the U-phase arm is connected to the U-phase coil, the intermediate point of the power switching elements Q3, Q4 of the V-phase arm is connected to the V-phase coil, and the intermediate point of the power switching elements Q5, Q6 of the W-phase arm is connected to the W-phase coil.

[0039] Thus, the relationship between the ON periods of the first power switching elements Q1, Q3, and Q5 on the power line side of each phase arm and the ON periods of the first power switching elements Q2, Q4, and Q6 on the ground line side is controlled (PWM controlled), so that the first power module 22 can convert the DC voltage of the external power source smoothed by the smoothing part 21 into a three-phase AC voltage and supply it to the electric motor 4, and thus drive the electric motor 4 and the compression mechanism 3.

[0040] The first driver circuit 23 drives the first power switching elements Q1 to Q6 for on / off (PWM control) based on a control signal (PWM signal) from a control unit 15 described below of the combination device 1.

[0041] That is, in the present embodiment, the operation of the motor drive circuit 20 (first power switching elements Q1 to Q6) and thus the operation of the electric motor 4 and the compression mechanism 3 (refrigerant compression function) is controlled by the control unit 15.

[0042] Fig. 6 is a view showing a configuration example of the essential part of the heater control circuit 30. In the present embodiment, the heater control circuit 30 is configured to apply the voltage of the high-voltage power source to the electric heater 5, and includes a second power module 31 and a second drive circuit 32.

[0043] The second power module 31 includes two power switching elements (hereinafter referred to as "second power switching elements") Q7, Q8 that control the energization of the electric heater 5. The second power switching elements Q7, Q8 may be IGBTs, similar to the first power switching elements Q1 to Q6 of the motor drive circuit 20. In the present embodiment, one of the two second power switching elements Q7, Q8 is provided closer to the output side (voltage side) of the high-voltage power source than the electric heater 5, while the other second power switching element Q8 is provided closer to the ground side of the high-voltage power source than the electric heater 5.

[0044] The second power module 31 can switch the power supply of the electric heater 5 on / off by controlling the second power switching elements Q7, Q8 (PMW controlled), whereby the temperature of the electric heater 5 and also the temperature of the heating medium heated by the electric heater 5 can be controlled.

[0045] The second driver circuit 32 drives the second power switching elements Q7, Q8 for on / off switching (PWM control) based on a control signal (PWM signal) from a control unit 15 of the combination device 1 described below.

[0046] That is, in the present embodiment, the operation of the heater control circuit 30 (second power switching elements Q7, Q8) and thus the operation of the electric heater 5 (heating medium heating function) is controlled by the control unit 15.

[0047] The arrangement structure of the first power switching elements Q1 to Q6 of the motor drive circuit 20 and the second power switching elements Q7, Q8 of the heater control circuit 30 in the combination device 1 according to the embodiment will now be described with reference to Fig. 7 explained. Fig. Figure 7 shows a partially schematic sectional view of the combination device 1 (corresponding to the BB sectional view of Fig. 3).

[0048] As described above, the motor drive circuit 20 and the heater control circuit 30 are mounted on a circuit board 6 and housed within the third housing 2C. The circuit board 6 can be mounted on a plurality of substrate mounting parts 12 provided within the third housing 2C, as shown in Fig. 7. In the present embodiment, each of the plurality of substrate fixing parts 12 is formed in the shape of a protrusion protruding from the bottom wall 7 of the third case 2C (in a direction away from the first case 2A and the second case 2B), and the circuit board 6 is fixed to the top of the plurality of substrate fixing parts 12 by screws 13.

[0049] The first power switching elements Q1 to Q6 of the motor drive circuit 20 and the second power switching elements Q7, Q8 of the heater control circuit 30 are arranged in the third housing 2C in a position in which they can be cooled by the refrigerant flowing into the first housing 2A from the refrigerant inlet 8 and the heating medium flowing into the second housing 2B from the heating medium inlet 10.

[0050] Specifically, the first power switching elements Q1 to Q6 of the motor drive circuit 20 are mounted on a surface on the bottom wall 7 side of the third case 2C of the circuit board 6 mounted on the substrate mounting part 12, and each is in thermal contact with a part of the second partition part 72 on the first partition part 71 side, preferably with a part of the second partition part 72 adjacent to the first partition part 71 (across the boundary).

[0051] The second power switching elements Q7, Q8 of the heater control circuit 30 are mounted on a surface on the bottom wall 7 side of the third case 2C of the circuit board 6 mounted on the substrate mounting part 12, and each is in thermal contact with a part of the first partition part 71 on the second partition part 72 side, preferably with a part of the first partition part 71 adjacent to the second partition part 72 (across the boundary).

[0052] The term "being in thermal contact with X" means the state in which heat exchange with X is possible and includes being in direct contact with X, being in the vicinity of X and being in indirect contact with X via a heat exchange element or the like with high thermal conductivity.

[0053] Fig. Figure 8 is a block diagram showing the schematic configuration of a control system of the combination device 1 according to the embodiment. The combination device 1 includes the control unit 15, which controls the overall operation of the combination device 1. In the present embodiment, an operation / stop command for the refrigerant compression function and an operation / stop command for the heating medium heating function are input to the control unit 15 from a higher-level control device (e.g., the control device of the vehicle air conditioner described above).

[0054] The control unit 15 also receives the detection signals of various detection parts, such as a speed detection part 51 that detects the speed of the electric motor 4, a first temperature detection part 52 that detects the temperature of the first power switching elements Q1 to Q6, and a second temperature detection part 53 that detects the temperature of the second power switching elements Q7, Q8. The speed detection part 51 can be used to calculate the speed of the electric motor 4. The first temperature detection part 52 can detect a value correlated with the temperature of the first power switching elements Q1 to Q6, and the second temperature detection part 53 can detect a value correlated with the temperature of the second power switching elements Q7, Q8.

[0055] Furthermore, in the present embodiment, the control unit 15 is communicatively connected to a pump control device 60 that controls the pump part for circulating the heating medium in the heating medium circuit, and is configured such that by outputting an operation request of the pump part (hereinafter referred to as "pump operation request") to the pump control device 60, the pump part can be operated via the pump control device 60, that is, the heating medium can circulate in the heating medium circuit.

[0056] The control unit 15 is further configured to control the operation of the refrigerant compression function and the heating medium heating function of the combination device 1 based on commands from the higher-level control device and the detection results of the various detection parts. The operation control of the refrigerant compression function and the operation control of the heating medium heating function by the control unit 15 will be explained below.

[0057] The Fig. 9 and Fig. 10 show flowcharts of an example of the operation control of the refrigerant compression function by the control unit 15.

[0058] In step S1, the control unit 15 judges whether an operation command for the refrigerant compression function has been input. If the operation command for the refrigerant compression function has been input (step S1; YES), the control unit 15 proceeds to the processing of step S2.

[0059] In step S2, the control unit 15 operates the refrigerant compression function. That is, the control unit 15 drives the first power switching elements Q1 to Q6 to turn on / off by sending a control signal (PWM signal) corresponding to the operation command for the refrigerant compression function to the first drive circuit 23, thereby driving the electric motor 4 to operate the refrigerant compression function.

[0060] In step S3, the control unit 15 judges whether the rotational speed of the electric motor 4 (hereinafter referred to as "engine speed") is below a predetermined speed. If the engine speed exceeds the predetermined speed (step S3; NO), the control unit 15 proceeds to the processing of step S4.

[0061] In step S4, the control unit 15 judges whether a stop command for the refrigerant compression function has been input. If the stop command for the refrigerant compression function has been input (step S4; YES), the control unit 15 proceeds to the processing of step S5, and if no stop command for the refrigerant compression function has been input (step S4; NO), the control unit 15 returns to the processing of step S2.

[0062] In step S5, the control unit 15 stops the operation of the refrigerant compression function. That is, the control unit 15 stops the operation of the refrigerant compression function by stopping the electric motor 4 and stopping the output of the control signal (PWM signal) to the first driver circuit 23. When the operation of the refrigerant compression function is stopped, the control unit 15 ends the present process.

[0063] If the engine speed is below the predetermined speed in step S3 (step S; YES), ie, the electric motor 4 is operated at a low speed below the predetermined speed, the control unit 15 proceeds to the processing of step S6.

[0064] In step S6, the control unit 15 detects the temperature of the first power switching elements Q1 to Q6 (hereinafter referred to as "first switching element temperature"). This detection is based on the detection signal of the first temperature detection part 52.

[0065] In step S7, the control unit 15 judges whether the first switching element temperature detected in step S6 is above a first threshold temperature. If the first switching element temperature is below the first threshold temperature (step S7; NO), the control unit 15 proceeds to the processing of step S4, and if the first switching element temperature is above the first threshold temperature (step S7; YES), the control unit 15 proceeds to the processing of step S8.

[0066] In step S8, the control unit 15 judges whether the first switching element temperature detected in step S6 is above a second threshold temperature (> first threshold temperature). If the first switching element temperature is below the second threshold temperature (step S8; NO), the control unit 15 proceeds to the processing of step S9.

[0067] In step S9, the control unit 15 outputs the pump operation request to the pump control device 60. This starts the pump part operating, and the heating medium circulates in the heating medium circuit (ie, the heating medium flows inside the second housing 2B).

[0068] In step S10, the control unit 15 judges whether a stop command for the refrigerant compression function has been input. If the stop command for the refrigerant compression function is input (step S10; YES), the control unit 15 proceeds to step S11 and outputs the cancellation of the pump operation request to the pump control device 60, and then proceeds to the processing of step S5. That is, the control unit 15 stops the operation of the refrigerant compression function. On the other hand, if no stop command for the refrigerant compression function has been input (step S11; NO), the control unit 15 returns to the processing of step S6.

[0069] If the first switching element temperature is above the second threshold temperature in the processing of step S8 (step S8; YES), the control unit 15 proceeds to the processing of step S12 to forcibly stop the operation of the refrigerant compression function. That is, the control unit 15 immediately stops outputting the control signal (PWM signal) to the first driver circuit 23. This is done to protect the first power switching elements Q1 to Q6 from overheating. When the operation of the refrigerant compression function is forcibly stopped, the control unit 15 ends the present process. If the pump operation request has already been issued to the pump control device 60, the control unit 15 outputs the cancellation of the pump operation request to the pump control device 60.

[0070] Fig.11 is a flowchart showing an example of the operation control of the heating medium heating function by the control unit 15.

[0071] In step S21, the control unit 15 judges whether an operation command for the heating medium heating function has been input. If the operation command for the heating medium heating function has been input (step S21; YES), the control unit 15 proceeds to the processing of step S22.

[0072] In step S22, the control unit 15 operates the heating medium heating function, that is, the control unit 15 outputs a control signal (PWM signal) to the second driver circuit 32 according to the heating medium heating function operation command to turn the second power switching elements Q7, Q8 on and off, thereby operating the electric heater 5 to operate the heating medium heating function.

[0073] In step S23, the control unit 15 detects the temperature of the second power switching elements Q7, Q8 (hereinafter "second switching element temperature"). This detection is performed based on the detection signal of the second temperature detection part 53.

[0074] In step S24, the control unit 15 judges whether the second switching element temperature detected in step S23 is above the third threshold temperature. If the third switching element temperature is below the third threshold temperature (step S24; NO), the control unit 15 proceeds to the processing of step S25.

[0075] In step S25, the control unit 15 judges whether a stop command for the heating medium heating function has been input. If no stop command for the heating medium heating function has been input (step S25; NO), the control unit 15 returns to the processing of step S23. Conversely, if the stop command for the heating medium heating function has been input (step S25; YES), the control unit 15 proceeds to the processing of step S26.

[0076] In step S26, the control unit 15 stops the operation of the heating medium heating function. That is, the control unit 15 stops the operation of the heating medium heating function by stopping the electric heater 5 and stopping the output of the control signal (PWM signal) to the second driver circuit 32. When the operation of the heating medium heating function is stopped, the control unit 15 ends the present process.

[0077] If the third switching element temperature in step S24 is above a third threshold temperature (step S24; YES), the control unit 15 proceeds to the processing of step S27 to forcibly stop the operation of the heating medium heating function. That is, the control unit 15 immediately stops outputting the control signal (PWM signal) to the second driver circuit 32. This is done to protect the second power switching elements Q7, Q8 from overheating. If the operation of the heating medium heating function is forcibly stopped, the control unit 15 terminates the present process.

[0078] With the combination device 1 according to the embodiment, the following effects are achieved.

[0079] The combination device 1 includes the first housing (compressor housing) 2A in which the compression mechanism 3 for compressing the refrigerant and the electric motor 4 for driving the compression mechanism 3 are housed in series inside, the second housing (heater housing) 2B in which the electric heater 5 for heating the heating medium is housed inside, and the third housing (circuit housing) 2C in which the motor drive circuit 20 for controlling the electric motor 4 and the heater control circuit 30 for controlling the electric heater 5 are housed.The first housing 2A includes the refrigerant inlet 8, which admits the refrigerant compressed by the compression mechanism 3, and the refrigerant outlet 9, which discharges the refrigerant compressed by the compression mechanism 3 to the outside. The second housing 2B includes the heating medium inlet 10, which admits the heating medium heated by the electric heater 5, and the heating medium outlet 11, which discharges the heating medium heated by the electric heater 5 to the outside. The first housing 2A, the second housing 2B, and the third housing 2C are integrally connected to each other.

[0080] The combination device 1 can function as a refrigerant compressor (electric compressor) for compressing the refrigerant and as a heating medium heating device for heating the heating medium, and can heat the heating medium while compressing the refrigerant. Therefore, the combination device 1 can be applied to the vehicle air conditioning systems described above. By applying the combination device 1 to the vehicle air conditioning systems, it is possible to downsize the vehicle air conditioning system compared to conventional designs with a separate electric compressor and heating medium heating device.

[0081] In the third housing 2C, the first power switching elements Q1 to Q6 of the motor drive circuit 20 are arranged so that they can be cooled by the refrigerant flowing into the first housing 2A and the heating medium flowing into the second housing 2B. Specifically, the first power switching elements Q1 to Q6 are arranged so that they are in thermal contact with a part of the first partition 71 separating the interior of the first housing 2A and the interior of the third housing 2C on the side of the second partition 72 separating the interior of the second housing 2B and the interior of the third housing 2C. The refrigerant inlet 8 of the first housing 2A is provided near the first partition 71, and the heating medium inlet 10 of the second housing 2B is provided near the second partition 72.

[0082] The part of the first partition 71 on the side of the second partition 72 can be cooled by the refrigerant flowing into the first housing 2A and also by the heating medium flowing into the second housing 2B. Therefore, the first power switching elements Q1 to Q6 are cooled by heat exchange with and from the part of the first partition 71 on the side of the second partition 72, which can be cooled by the refrigerant flowing into the first housing 2A and the heating medium flowing into the second housing 2B. Consequently, the cooling performance (heat radiation) of the first power switching elements Q1 to Q6 is ensured.

[0083] When the electric motor 4 (ie, the refrigerant compression function) is operated at a low speed below a predetermined speed, the control unit 15 further outputs the pump operation request to the pump control device 60, which controls the pump part that circulates the heating medium in the heating medium circuit, thereby operating the pump part to admit the heating medium into the interior of the second housing 2B.

[0084] When the electric motor 4 is operated at low speed, the amount of refrigerant flowing into the first housing 2A, the cooling capacity of the first separating part 71, and thus the cooling capacity of the first power switching elements Q1 to Q6 decrease. In the present embodiment, when the electric motor 4 is operated at low speed, the pump operation request is output to the pump control device 60, whereby the heating medium is admitted into the second housing 2B. Therefore, the heating medium cools the part of the first separating part 71 on the second separating part 72 side, resulting in cooling of the first power switching elements Q1 to Q6 by the heating medium. That is, the cooling by the heating medium can compensate for the reduced cooling capacity of the refrigerant for the first power switching elements Q1 to Q6.Consequently, the cooling performance (heat radiation conduction) of the first power switching elements Q1 to Q6 is ensured even when the electric motor 4 is operated at low speed.

[0085] The control unit 15 is further configured to output the pump operation request to the pump control device 60 when the temperature of the first power switching elements Q1 to Q6 is higher than the first threshold temperature. Therefore, the reduction in cooling capacity by the refrigerant for the first power switching elements Q1 to Q6 can be effectively and efficiently compensated for by the cooling by the heating medium.

[0086] Furthermore, the control unit 15 is configured to forcibly stop the operation of the refrigerant compression function (electric motor 4) when the temperature of the first power switching elements Q1 to Q6 exceeds the second threshold temperature (> first threshold temperature). This enables protection of the first power switching elements Q1 to Q6 from overheating.

[0087] In the above-described embodiment, the control unit 15 outputs the pump operation request to the pump control device 60. However, this is not limited to this. The control unit 15 may be configured to output the pump operation request to a control device other than the pump control device 60 (e.g., the higher-level control device), whereby the control device issues an operation command of the pump part to the pump control device 60. That is, the pump control device 60 may operate the pump part based on the pump operation request output from the control unit 15, and the "output of the pump operation request to the pump control device 60" includes the indirect output of the pump operation request to the pump control device 60 via other control devices, etc.

[0088] The control unit 15 can change the pump operation request (content of the pump operation request) depending on the temperature of the first power switching elements Q1 to Q6. For example, the pump operation request includes information about the flow rate of the heating medium circulating in the heating medium circuit, and the control unit 15 can output to the pump control device 60 a pump operation request that is changed such that the flow rate of the heating medium circulating in the heating medium circuit (ie, the flow rate of the heating medium flowing inside the second housing 2B) is higher the higher the temperature of the first power switching elements Q1 to Q6.

[0089] Furthermore, in the embodiment described above, the motor drive circuit 20 and the heater control circuit 30 are mounted on a single circuit board 6. However, this is not limited to this. The motor drive circuit 20 and the heater control circuit 30 may also be mounted on separate circuit boards, or the motor drive circuit 20 and / or the heater control circuit 30 may be split and mounted on multiple circuit boards.

[0090] In the above embodiment, it is further explained that the combination device 1 is mainly applied to vehicle air conditioning systems. However, this is not limited to this. The combination device 1 can be applied to various devices and systems that use an electric compressor for compressing a refrigerant and a heating medium heating device for heating a heating medium.

[0091] Although the embodiment of the present invention has been explained above, it goes without saying that the present invention is not limited to the above-described embodiment, and can be redesigned and changed based on the technical concept of the present invention. LIST OF REFERENCE SYMBOLS 1 combination device 2 housings 2A first housing (compressor housing) 2B second housing (heater housing) 2C third housing (circuit housing) 3 Compression mechanism 4 electric motor 5 electric heater 6 circuit board 7 Floor wall 8 Refrigerant inlet 9 Refrigerant outlet 10 Heating medium inlet 11 Heating medium outlet 15 Control unit 20 Motor drive circuit 30 Heating control circuit 51 Speed ​​​​measuring part 52 first temperature detection part 53 second temperature detection part 60 Pump control device 71 first dividing part 72 second separating part Q1 to Q6 first power switching elements (switching elements of the motor drive circuit) Q7, Q8 second power switching elements QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2014-213765 A

[0003]

Claims

[1] Combination device with a refrigerant compression function and a heating medium heating function, comprising: a compression mechanism for compressing a refrigerant, an electric motor to drive the compression mechanism, a compressor housing that houses the compression mechanism and the electric motor in series inside, and has a refrigerant inlet that admits the refrigerant compressed by the compression mechanism into the interior, and a refrigerant outlet that discharges the refrigerant compressed by the compression mechanism to the outside, an electric heater for heating a heating medium, a heater housing which houses the electric heater inside, and has a heating medium inlet which admits the heating medium heated by the electric heater into the interior, and a heating medium outlet which discharges the heating medium heated by the electric heater to the outside, a motor drive circuit for controlling the electric motor, a heating control circuit for controlling the electric heater, and a circuit housing that houses the motor drive circuit and the heater control circuit inside, characterized by that the compressor housing, the heater housing and the circuit housing are connected to each other in one piece, the motor drive circuit has switching elements that convert DC voltage into AC voltage, and the switching elements of the motor drive circuit are arranged in the circuit housing in such a way that the switching elements can be cooled by a refrigerant flowing into the compressor housing and can also be cooled by a heating medium flowing into the heater housing. [2] Combination device according to claim 1, wherein the interior of the compressor housing and the interior of the circuit housing are divided by a first partition part, and the interior of the heater housing and the interior of the circuit housing are divided by a second partition part adjacent to the first partition part, the refrigerant inlet of the compressor housing is provided near the first separating part, the heating medium inlet of the heater housing is provided near the second separating part, and Switching elements of the motor drive circuit are arranged in the circuit housing such that the switching elements are in thermal contact with a part of the first separating part which is closer to the second separating part. [3] Combination device according to claim 1 or 2, which is installed and used in a refrigerant circuit in which the refrigerant circulates, and in a heating circuit in which the heating medium circulates by means of a pump part, further comprises: a speed detection part for detecting the speed of the electric motor and a control unit which controls the overall operation of the combination device and is communicatively designed with a pump control device for controlling the pump part, wherein the control unit is configured such that the control unit outputs a pump operation request to the pump control device when the electric motor is operated at a low speed below a predetermined speed, thereby activating the pump part to admit the heating medium into the interior of the heater housing. [4] Combination device according to claim 3, further comprising: a temperature detection part for detecting the temperature of switching elements of the motor drive circuit, wherein the control unit issues a pump operation request to the pump control device when the electric motor is operating at a low speed below a predetermined speed and the temperature of the switching elements of the motor drive circuit is above a first threshold temperature. [5] The combination device according to claim 4, wherein the control unit forcibly stops the electric motor when the temperature of the switching elements of the motor drive circuit is above a second threshold temperature which is higher than the first threshold temperature.

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