JP3266026B2 - Automotive air conditioners - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric compressor driving device for driving an electric compressor by a DC power source such as a battery, and an air conditioner for an automobile having an electric compressor.

[0002]

2. Description of the Related Art In an automotive air conditioner equipped with an electric compressor driving device for driving an air-conditioning electric compressor with DC power, the electric compressor driving device for driving the air-conditioning electric compressor supplies a large current to the electric compressor. Therefore, the electric noise is large and interferes with the on-vehicle radio.

Therefore, as shown in the conventional electric noise countermeasure diagram of FIG. 7, the case of the electric compressor driving device 5 and the electric compressor 7 is made of metal, and the electric compressor driving device 5 and the electric compressor driving device 5
Electric compressor drive 5 and electric compressor 7
Is a shielded wire, and this shield is connected to a metal case of the electric compressor driving device 5 and the electric compressor 7.

[0004] In order to enhance the shielding property, a metal case of the electric compressor driving device 5 and the electric compressor 7 is connected to the vehicle body.

[0005]

In the above conventional case, the effect of the shield is exhibited only when the electric compressor 7, the electric compressor driving device 5, including the battery 1, and all the electric wires connecting them are shielded.

However, since the battery 1 is composed of about 30 12V batteries, the battery 1 has a large space and a high voltage (for example, about 300V).

For this reason, it is difficult to shield the battery 1 and the location of the battery 1 is not shielded. Therefore, electric noise is radiated from here.

Further, even if the battery 1 can be shielded, the battery 1 is large and large in order to maintain strength and space. Therefore, it becomes expensive.

The shield power supply line 9 is expensive because it is used for high voltage and large current. The shield power supply line 9 is long to connect the battery 1 to the electric compressor driving device 5. As a result, costs increase.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an air conditioner for a vehicle which is a small-sized, light-weight, low-cost device and can sufficiently prevent radiation of electric noise.

[0011]

According to the present invention, a low-pass high-frequency filter is connected between a DC voltage generating means and an electric compressor driving device, and each of the low-pass high-frequency filter, the electric compressor driving device and the electric compressor is connected. A shield member for shielding electromagnetic radiation from the electric circuit section and each connection wire.

[0012]

According to the present invention, a low-pass high-frequency filter is connected between a DC voltage generating means and an electric compressor driving device, and each of the low-pass high-frequency filter, the electric compressor driving device, and the electric compressor is connected. A shield member for shielding electromagnetic radiation from the electric circuit section and each connection wire.

Therefore, it is possible to prevent electromagnetic radiation from the low-pass high-frequency filter, the electric compressor driving device, the electric circuit of each electric compressor, and the connecting wires.

Further, since the low-pass high-frequency filter can prevent electric noise from being output from the electric compressor driving device to the DC voltage generating means, it is not necessary to shield the DC voltage generating means.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 1 shows an electric noise countermeasure diagram according to a first embodiment of the present invention. The difference from the conventional electric noise countermeasure diagram of FIG. 7 is that the low-pass high-frequency filter 3 is connected between the battery 1 and the electric compressor driving device 5, and the shield power line 9 becomes the first power line 2. That is the point.

The source of the electric noise is the electric compressor driving device 5. Therefore, the case of the electric compressor drive device 5 is made of a metal or the like having an electromagnetic shielding ability (a resin may be used as long as it has an electromagnetic shielding ability).

The case of the electric compressor 7 is also
Due to its structure (built-in motor, piston, etc.), metal (iron,
Aluminum). The case of the low-pass high-frequency filter 3 is also made of a metal or the like having an electromagnetic shielding ability (a resin may be used if it has an electromagnetic shielding ability).

Therefore, the electric compressor driving device 5,
Direct electric noise radiation from inside each of the electric compressor 7 and the low-pass high-frequency filter 3 is shielded.

On the other hand, a shielded power supply line 9 (having electromagnetic shielding ability) between the low-pass high-frequency filter 3 and the electric compressor driving device 5 is connected to the electric current-carrying electric wire by the electric compressor driving device 5 and the electric compressor 7. A shielded motor wire 10 (having electromagnetic shielding capability) is used between the two, and electric noise radiation from the electric wire is shielded.

The shield portions of the shield power supply line 9 and the shield motor line 10 include an electric compressor driving device 5, an electric compressor 7, a low-pass high-frequency filter 3,
It is electrically connected to each case to prevent leakage of electric noise.

The characteristics of the low-pass high-frequency filter 3 are shown in FIG. 6 as a characteristic diagram of the low-pass high-frequency filter. Low frequency components are allowed to pass and high frequencies are not allowed to pass. Here, radio A
0.3 MHz or more is attenuated so as not to interfere with M broadcast.

Therefore, since electric noise does not leak to the power supply line, the first power supply line 2 does not need to be a shield line, and may be a normal power supply line.

The frequency component to be passed is set so that the operating current of the electric compressor driving device 5 can flow. Inverter circuit whose switching frequency is 10KHz
In this case, if the current is smoothed internally, the frequency may be 10 KHz or less.

FIG. 4 shows a first low-pass high-frequency filter circuit diagram according to the present invention, and FIG. 5 shows a second low-pass high-frequency filter circuit diagram according to the present invention. As shown. 4, the choke action of the coil 17 and the bypass action of the capacitor 18 prevent electric noise (from the low-pass high-frequency filter 3 to the power line A2) from flowing out.

If the required characteristics can be achieved, the coil 17,
Only one of the capacitors 18 may be used. Further, not limited to this, various methods can be considered.

In FIG. 5, the coil 17 is compatible with the common mode, and the direction in which the voltage is induced is indicated by a black circle. Thereby, the influence on the operating current of the electric compressor drive device 5 can be reduced.

In FIG. 1, each case of the electric compressor driving device 5, the electric compressor 7, and the low-pass high-frequency filter 3 is electrically connected to the vehicle body 13 to enhance the electromagnetic shielding property. Since there are no leaking parts, it is not always necessary to connect each case to the vehicle body.

FIG. 2 shows an electrical noise countermeasure diagram according to a second embodiment of the present invention. The difference from the electric noise countermeasure diagram according to the first embodiment of the present invention shown in FIG. 1 is that an electric compressor driving device 5, an electric compressor 7, and a low-pass high-frequency filter 3 are surrounded by a shield case 8, and each case is Is a point that is electrically connected to the shield case 8 by a case and a shield case connection wire 15, and the shield wire is not used for the electric wire.

Direct electric noise radiation from inside the electric compressor drive device 5, electric compressor 7, and low-pass high-frequency filter 3 and electric noise radiation from electric wires are shielded by the shield case 8. Further, the low-pass high-frequency filter 3 prevents electric noise from leaking to the power supply line.

Here, the electric compressor driving device 5,
If the electric compressor 7 and the low-pass high-frequency filter 3 have high shielding properties, the case, the shield case connection line 15, the case, and the vehicle body connection line 14 are not necessarily required.

Further, a part may be taken out of the shield case 8. In that case, the electric wire that goes out of the shield case 8 (between the low-pass high-frequency filter 3 and the electric compressor 7) needs to be a shield wire.

FIG. 3 shows an electrical noise countermeasure diagram according to a third embodiment of the present invention. The difference from the circuit diagram of the automotive air conditioner according to the first embodiment of the present invention shown in FIG. 1 is that the electric compressor driving device 5 and the low-pass high-frequency filter 3 are integrated, and the low-pass high-frequency filter is built in. The point is that the electric compressor drive device 16 is provided, and the shield power supply line 9 is omitted.

The shielding property against electric noise is improved because the number of electric wire connection portions is reduced and the leakage of electric noise is reduced.
With this configuration, the case of the low-pass high-frequency filter 3,
The shield power supply line 9 becomes unnecessary and the size is reduced. Workability,
The cost is also improved.

It should be noted that the present invention is not limited to the above-described embodiment, and various methods are possible within a range satisfying the gist of the present invention.

[0036]

According to the present invention, a low-pass high-frequency filter is connected between the DC voltage generating means and the electric compressor driving device, and the electric circuit of each of the low-pass high-frequency filter, the electric compressor driving device, and the electric compressor is provided. And a shielding material for shielding electromagnetic radiation from the connecting wires and the respective connecting wires.

For this reason, it is possible to prevent electromagnetic radiation from the low-pass high-frequency filter, the electric compressor driving device, the electric circuit of each electric compressor, and the connecting wires.

Further, since the low-pass high-frequency filter can prevent electric noise from being generated from the electric compressor driving device to the DC voltage generating means, it is not necessary to shield the DC voltage generating means with a large, heavy and expensive shield device. Absent. An expensive shield line is not required between the DC voltage generating means and the low-pass high-frequency filter.

The electrical connection from each case to the vehicle body is as follows:
Since it is not always necessary, leakage of electric noise due to forgetting to connect or increasing the electric resistance of the connecting portion can be prevented.

Thus, a small, lightweight, low-cost device
Electric noise emission can be reliably prevented.

By integrating the electric compressor driving device and the low-pass high-frequency filter, further downsizing can be achieved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a countermeasure for electric noise according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a countermeasure against electric noise according to a second embodiment of the present invention.

FIG. 3 is an explanatory diagram of a measure against electric noise according to a third embodiment of the present invention.

FIG. 4 is a circuit diagram of a first low-pass high-frequency filter according to the present invention;

FIG. 5 is a circuit diagram of a second low-pass high-frequency filter according to the present invention;

FIG. 6 is a characteristic diagram of a low-pass high-frequency filter according to the present invention.

FIG. 7 is an explanatory diagram of a conventional countermeasure against electric noise.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Battery 2 1st power supply line 3 Low-pass high frequency filter 4 2nd power supply line 5 Electric compressor drive 6 Motor line 7 Electric compressor 8 Shield case 9 Shield power supply line 10 Shield motor line 12 Shield line, case connection line 13 Body 14 Case, Body connection line 15 Case, Shield case connection line 16 Electric compressor drive with built-in low-pass high-frequency filter 17 Coil 18 Capacitor

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-304327 (JP, A) JP-A-3-243136 (JP, A) JP-A-63-99762 (JP, A) JP-A-58- 99000 (JP, A) JP-A-59-84613 (JP, A) JP-A-56-144620 (JP, A) JP-A-8-98328 (JP, A) JP-A-1-321864 (JP, A) JP-A-5-292669 (JP, A) JP-A-3-45091 (JP, U) JP-A-2-113236 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60H 1/32 H02M 7/48

Claims (1)

(57) [Claims] 1. A supplied with a DC voltage generating means, and <br/> electric compressor having a metal housing, the direct current <br/> force from said DC voltage generating means, a metal that drives the electric compressor Made
Electricity between the electric compressor driving device including a housing, and said DC voltage generating means and said electric compressor driving device
AM frequency with metal enclosure connected to air
The AM band cutoff filter and the AM band cutoff filter,
Between the electric compressor drive and the electric compressor
And a shield wire for electrically connecting the shield wire,
The shield part is the AM band cutoff filter, the electric
Presser drive unit, gold for each of the electric compressors
A vehicle air conditioner electrically connected to a metal housing .