JP4699085B2 - Electric compressor for vehicles - Google Patents

Description

  The present invention relates to a vehicular electric compressor used in an air conditioner for a vehicle such as an electric vehicle.

2. Description of the Related Art In recent years, vehicles that use electric power, such as electric vehicles and hybrid vehicles, have been rapidly developed and introduced into the market. In such a vehicle air conditioner equipped in such a vehicle, an electric compressor that uses electricity as power for driving a compressor that compresses and sends out refrigerant is employed, unlike a vehicle that runs on an internal combustion engine. Has been.
Such an electric compressor generally employs a hermetic compressor configuration in which a compression mechanism and an electric motor are housed in the same housing. Furthermore, the electric compressor of the vehicle air conditioner includes an inverter control device that performs operation control by supplying electric power input from the power source to the electric motor, and this inverter control device is installed separately from the compressor. Yes.

In addition, as a conventional technology for a refrigeration apparatus that performs inverter control (particularly, an outdoor unit of an air conditioner), the refrigeration apparatus and the inverter apparatus are miniaturized and an inverter or the like is mounted for the purpose of improving the reliability of the refrigeration cycle. It has been proposed to fill the power semiconductor surface of the substrate with gel. In this prior art, the power semiconductor element is protected by filling the gel, and further, the gel surface is insulated by encapsulating the resin, so that the reliability of the power module is improved. (For example, see Patent Document 1)
JP 2004-053050 A (paragraph number [0023] and FIG. 5 etc.)

Incidentally, a vehicular electric compressor (hereinafter referred to as an “electric compressor”) used in a vehicular air conditioner is an engine room together with an electric motor that generates a driving force for driving a vehicle, an internal combustion engine for driving a generator, and the like. Installed inside. As a result, the installation environment is easily affected by high-temperature radiant heat and vibration, and various electrical and electronic components (for example, power elements and capacitors) that constitute the inverter control device are protected from the surrounding environment to guarantee operation. Therefore, a cooling structure and vibration measures are required.
In addition, the equipment installed in the engine room must withstand use in an environment with a large temperature change from a low temperature of about −40 ° C. to a high temperature of about several hundreds of degrees Celsius. For these electrical devices, it is necessary to take measures against water droplets generated by condensation.

From such a background, measures for radiant heat, vibration, and water droplets are indispensable for the electric compressor used in the vehicle air conditioner in order to ensure reliability and durability.
This invention is made | formed in view of such a situation, Comprising: It aims at providing the electric compressor for vehicles by which the countermeasure with respect to a radiant heat, a vibration, and a water droplet was given.

In order to solve the above problems, the present invention employs the following means.
A vehicular electric compressor according to claim 1 of the present invention is a vehicular electric compressor in which a compression mechanism is driven by an electric motor to compress refrigerant in a vehicular air conditioner. In this case, the insulating gel agent is filled only to the height of the electrical component having a large calorific value such as a CPU or a power element.

According to the electric compressor for a vehicle according to claim 1, only the height of electrical components having a large calorific value, such as a CPU and a power element, is housed in a housing that houses and installs control devices of a control device that controls the electric motor. Since the insulating gel agent is filled, the electric parts in the casing covered with the insulating gel are electrically insulated and water droplets are prevented from entering. Furthermore, in the electrical parts in the housing covered with the insulating gel, the vibration of the substrate or the like is reduced, and the fixing screws and the like are also prevented from loosening due to the vibration.

In the vehicular electric compressor according to claim 1, it is preferable that the control device is installed in close contact with a low-pressure refrigerant chamber of a housing that houses the compression mechanism. The electric component of the control device can be cooled by the gas refrigerant. In the inverter control device, an arrangement that efficiently cools power elements that generate a large amount of heat, condensers that are preferably cooled, and the like is particularly preferable.

Further, in the vehicle electric compressor according to claim 2 , the low-pressure refrigerant chamber is provided with a refrigerant inlet for taking in the refrigerant, the electrical component includes a power element, and the power element is It is desirable that it is disposed at a position close to the refrigerant intake.
Moreover, in the electric compressor for vehicles according to claim 2 or 3 , it is desirable for the housing which stores the compression mechanism to have a bottomed cylindrical shape.

According to the vehicle electric compressor of the present invention, the control equipment constituting the control device such as an inverter control device for controlling the electric motor is such that the electrical components housed and installed in the housing are covered with the insulating gel agent. The electric parts in the housing are electrically insulated, water droplets are prevented from entering, and the influence of vibration can be reduced.
Further, since the control device is cooled by the low-temperature gas refrigerant in the low-pressure refrigerant chamber, for example, in the inverter control device, it is possible to effectively cool the power element, the capacitor, and the like.
Therefore, even if the inverter-controlled vehicle electric compressor is installed in the engine room, it is possible to obtain a remarkable effect that the reliability and durability are improved in response to the installation environment of high temperature, high humidity and high vibration.

Hereinafter, an embodiment of an electric compressor for a vehicle according to the present invention will be described with reference to FIGS. 1 to 3.
The vehicular electric compressor described in the present embodiment is used in a refrigerant circuit of a vehicular air conditioner installed in a vehicle that travels using electric power, such as an electric vehicle or a hybrid vehicle. This electric compressor for vehicles employs an electric motor that uses electricity as power to drive a compression mechanism that compresses low-temperature and low-pressure gas refrigerant (intake refrigerant) and sends it to a refrigerant circuit.
Such a vehicular electric compressor (hereinafter referred to as “electric compressor”) 1 is a hermetically sealed type in which a compression mechanism (not shown) such as a scroll compression mechanism and an electric motor (not shown) are built in the same housing 2. A compressor configuration is generally employed. Moreover, such an electric compressor 1 is provided with the inverter control apparatus 10 which supplies the electric power input from the power supply to an electric motor, and performs operation control. The inverter control device 10 is installed in close contact with the housing 2 of the electric compressor 1. The inverter control device 10 is electrically connected to a power supply unit 20 that supplies power to the inverter control device 10 and a power supply control device 21 that controls operations of the inverter control device 10 and the power supply unit 20.

The housing 2 has a hollow cylindrical shape that is installed with its axis substantially horizontal.
Specifically, as shown in FIGS. 1 and 3, the housing 2 has a bottomed cylindrical first storage portion (housing main body) 2a having an opening at one end and storing an electric motor therein, It is divided in two into a bottomed cylindrical second storage part (lid part) 2b having an opening at one end and storing the compression mechanism therein. The first storage part 2a and the second storage part 2b are joined together with the openings facing each other, and the flanges provided at both openings are fixed detachably by bolts, nuts, etc. ing.

In the present embodiment, a low-pressure refrigerant chamber of a compression mechanism (not shown) is formed inside the first storage portion 2a, and a refrigerant inlet 3 communicating with the internal low-pressure refrigerant chamber is formed on the outer peripheral surface of the first storage portion 2a. Is provided. The low-pressure refrigerant chamber is connected to the refrigerant circuit of the vehicle air conditioner through the refrigerant inlet 3, and low-temperature and low-pressure gas refrigerant vaporized through the indoor heat exchanger or the outdoor heat exchanger is fed into the low-pressure refrigerant chamber. ing.
That is, the outer peripheral surface and the bottom surface of the first storage portion 2a are cooled in comparison with the other portions of the housing 2 because the portion near the refrigerant inlet 3 is cooled by the low-temperature and low-pressure gas refrigerant that is the suction refrigerant. .

As shown in FIG. 1, a compressor base 4 is provided on the upper surface of the housing 2 along the longitudinal direction of the first storage portion 2 a. On the compressor base 4, electric components and electronic A protective case 11 is provided for a housing that houses the control equipment of the inverter control device 10 composed of electrical components such as components and forms an inverter chamber.
Here, the compressor base 4 and the protective case 11 are made of a light material having a high thermal conductivity such as aluminum or an aluminum base alloy. Further, the inverter control device 10 includes a control device including a circuit board 12 such as a CPU 12a and an electric component such as a power element 13 housed in a protective case 11, and a first storage portion having a bottomed cylindrical shape. And a capacitor 14 provided in close contact with the bottom surface of 2a. In this case, for example, the power element 13 having a large calorific value may be arranged at a position near the refrigerant intake 3 of the first storage portion 2a so as to perform efficient cooling with the sucked refrigerant. Further, the condenser 14 that is desirably cooled can be cooled by the sucked refrigerant because it is disposed in close contact with the bottom surface of the first storage portion 2a.
Of course, the electrical components of the inverter control unit 10 are insulated from the protective case 11 and the compressor base 4.

The protective case 11 that houses and installs the control devices of the inverter control device 10 is filled with the insulating gel 15 so as to fill the internal space after work such as electrical connection is completed. The filling gel agent 15 may be filled so as to completely fill the inside of the protective case 11, but it is sufficient that the filling gel agent 15 is filled to a position that completely covers at least an electrical component such as an electrical component or an electronic component. As a specific example, the electrical components such as the substrate 12 and the power element 13 are completely embedded in the insulating gel 15, and the electrical components are exposed in the upper space formed inside the protective case 10 to come into contact with air. What is necessary is just to fill to the position where it was prevented.
As the insulating gel agent 15 used here, for example, “KE1051J” manufactured by Shin-Etsu Chemical Co., Ltd. or an equivalent product is suitable.

When the insulating gel agent 15 is filled in the protective case 11 in this way, the electrical component is insulated, and it is effective for moisture and vibration.
First, the moisture prevention will be described. Since the engine room in which the electric compressor 1 integrated with the inverter control device 10 is installed is an environment in which the temperature change is large, water drops are generated due to condensation when the temperature is lowered in a high humidity state. Such water droplets such as condensed water cause troubles such as short-circuiting electrical components. However, if the electrical component is completely covered with the insulating gel agent 15, it is waterproofed so that water droplets do not reach the electrical component, so that it is possible to prevent problems such as a short circuit in the protective case 11.

  Next, image stabilization will be described. The environment in which the inverter control unit 10 is installed is directly input by the vibration of the electric compressor 1 in addition to the driving vibration of the vehicle and the driving source that drives the vehicle. For this reason, there is a concern that vibrations propagate to the substrate 12 to cause cracks in the printed wiring or the like, or troubles due to loosening of screws or the like for fixing electrical components such as the substrate 12 occur. However, if the periphery of the electrical component is covered with the insulating gel agent 15, the insulating gel agent 15 absorbs the vibration input from the outside and reduces the vibration acting on the electrical component, or the insulating gel agent 15 is the substrate. Since large vibrations such as 12 are suppressed, there is no occurrence of cracks or loosening of screws in the electrical parts such as the substrate 12.

  As described above, in the electric compressor 1 according to the present invention, heat transfer is performed with high efficiency between the first storage portion 2a and the inverter control device 10, so that the low-temperature gas refrigerant flows and becomes the low temperature side. Heat generated by the power element 13 and the like can be efficiently released to the storage portion 2a. Therefore, for example, when installing in a high temperature environment such as in an engine room of a vehicle, the low temperature gas refrigerant is used for the power element 13 and the capacitor 14 constituting the inverter control device 10 without using a special cooling structure. Therefore, the reliability and durability of the electric compressor 1 can be improved at a low cost.

In addition, since the electrical component housed and installed in the protective case 11 is covered with the insulating gel agent 15, the electrical component in the protective case 11 is electrically insulated and prevented from entering water droplets. The influence of vibration can also be reduced.
Therefore, even if the electric compressor 1 of the present invention described above is installed in an installation environment of high temperature, high humidity and high vibration as in an engine room, the insulating gel agent 15 is filled or cooled by effectively using the suction refrigerant. Since problems caused by the installation environment are solved and occurrence of problems is prevented, reliability and durability can be improved.
In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary of this invention, it can change suitably.

It is a figure which shows the structural example of the electric compressor for vehicles which concerns on one Embodiment of this invention, and is a partial cross section side view which shows the internal structural example of an inverter control part. It is the longitudinal cross-sectional view which looked at the inside of the inverter control part shown in FIG. 1 from the bottom face direction of the housing. 1 is a perspective view illustrating a configuration example of an electric compressor for a vehicle according to an embodiment of the present invention.

DESCRIPTION OF SYMBOLS 1 Vehicle electric compressor 2 Housing 2a 1st accommodating part 2b 2nd accommodating part 3 Refrigerant intake 4 Compressor base 10 Inverter control apparatus 11 Protective case (housing | casing)
12 Board (electric parts)
13 Power elements (electrical parts)
14 Capacitor 15 Insulating gel

Claims (4)

In the vehicle electric compressor for driving the compression mechanism by the electric motor and compressing the refrigerant of the vehicle air conditioner,
An electric vehicle for vehicles characterized in that an insulating gel agent is filled only to the height of electrical components having a large calorific value, such as a CPU and a power element , in a housing that houses and installs control devices of a control device that controls the electric motor. Compressor.   The electric compressor for a vehicle according to claim 1, wherein the control device is installed in close contact with a low-pressure refrigerant chamber of a housing that houses the compression mechanism. The low-pressure refrigerant chamber is provided with a refrigerant inlet for taking in the refrigerant,
The electrical component includes a power element,
The vehicular electric compressor according to claim 2, wherein the power element is disposed at a position close to the refrigerant inlet.   The electric compressor for a vehicle according to claim 2 or 3, wherein the housing that houses the compression mechanism has a bottomed cylindrical shape.

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