JPH09275676A - Dc-dc converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a DC-DC converter which has an easy installation structure for an input voltage supply-side case and which has a high cooling performance. SOLUTION: An opening 2a is made in a case 2 for a high-voltage section wherein input lines 3 from a main battery which produces DC high voltage are included. A case 11 for a main body 10 is installed in the opening 2a from outside the case 2, with lead-in sections of the input lines 3 being located inside the case 2 and those of output lines 4 being exposed outside the case 2. A cooling section 20 is installed on an external face of the case 11 which is exposed outside the case 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC-DC converter attached to an input side casing.

[0002]

2. Description of the Related Art For example, in an electric vehicle or the like, a power supply voltage of several hundred volts is required to drive a motor for driving wheels. On the other hand, lamps and accessories are often used with a 12-volt rating in order to share parts with those used in general gasoline vehicles. The output of the main battery (several hundreds of volts) for driving the electric motor of the electric vehicle cannot be used as it is as a power source for 12-volt rated lamps and auxiliary equipment. A converter is needed.

In a conventional DC-DC converter, a housing containing an input line connected to a main battery is used.
There are a built-in type mounted inside the housing and an external type mounted outside the housing.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the case of a built-in type DC converter, it is necessary to provide the housing with an output extraction portion for extracting the low-voltage output to the outside of the housing. In this output extraction part, D
The output line connected to the output terminal of the C-DC converter must penetrate the housing, and the waterproof property between the output line and the housing must be ensured. Therefore, the mounting structure of the DC-DC converter becomes complicated. In addition, attachment of the DC-DC converter to the housing is a work in the housing, which causes a problem in workability. In the case of the external type as well, in order to take out the output of the high voltage generator to the outside of the housing, it is necessary to provide the housing with an output take-out portion having a waterproof structure as in the case of the built-in type. Further, since the DC-DC converter is attached to the outside of the housing of the high voltage generator, the DC-DC converter
The case of the converter, the input part for introducing the input line into the case, and the output part for introducing the output line into the case must have a waterproof structure. Therefore, the structure of the DC-DC converter becomes complicated.

In addition, since the DC-DC converter generates heat during operation, it is often provided with a cooling means. In the case of the built-in type, this cooling means is provided, for example, outside the portion of the housing of the high-voltage generating unit to which the DC-DC converter is attached. However, in this case, the heat generated in the DC-DC converter is transmitted to the cooling means through the housing, so that the cooling performance becomes low. In the case of the external type, for example, the cooling means is fixed between the DC-DC converter and the housing. In this case, one side of the cooling means is DC
Since it comes into contact with the -DC converter, the heat generated in the DC-DC converter is directly transferred to the cooling means, but sufficient cooling performance may not be obtained because the other surface of the cooling means is in contact with the housing.

The present invention has been made in view of the above points, and an object thereof is to provide a DC-DC converter having a simple structure and excellent in workability of installation, and a DC-DC converter having high cooling performance. An object is to provide a DC converter.

[0007]

For this reason, according to the first aspect of the present invention, the case is attached to the housing which internally includes the input line connected to the voltage generating means for generating a high DC voltage. A DC-DC converter having a voltage converting means for converting an input high voltage applied via the input line into a low-voltage DC voltage and outputting the low-voltage DC voltage to an output line in the case, An opening is provided, and the case is
Positioning the introduction portion of the input line inside the casing and exposing the introduction portion of the output line outside the casing,
It is characterized in that it is attached to the opening.

According to this structure, the high DC voltage generated by the voltage generating means is input to the voltage converting means via the input line introduced into the case inside the housing and converted into the low voltage DC voltage. It The converted DC low voltage is output to the outside through an output line introduced into the case outside the housing. According to a second aspect of the invention, as a specific configuration of the first aspect of the invention, the case has the opening on the outer peripheral surface between the introduction portion of the input line and the introduction portion of the output line. It has a locking part for locking to, and the locking part is attached to the opening from the outside of the casing.

According to this structure, the case is inserted from the outside into the opening of the housing and is attached with the locking portion being locked in the opening. Therefore, the work of attaching the case to the housing is performed outside the housing. A third aspect of the invention is characterized in that, in the first or second aspect of the invention, a cooling unit is provided on an outer surface of the case exposed to the outside of the housing.

According to this structure, the heat generated by the voltage converting means is directly transmitted from the case to the cooling means and radiated to the outside (low temperature outside air). In the invention according to claim 4, in the invention according to any one of claims 1 to 3, the heat generating portion of the voltage converting means is arranged inside the case exposed to the outside of the housing. Is characterized by.

According to this structure, in the case,
The heat generating portion of the voltage converting means is arranged outside the housing, that is, on the side of low temperature outside air.

[0012]

As described above, according to the present invention, in the invention described in claim 1, the introduction portion of the input line is located inside the housing, and the introduction portion of the output line is exposed outside the housing. By attaching the case to the case like this, the conventional DC-D
The structure of the input part and the output part can be simplified as compared with the C converter.

According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, by attaching the locking portion provided on the case to the opening from the outside of the case, the case mounting work can be performed. Since it can be performed outside the housing, workability can be improved. In the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2,
Since the cooling means is provided on the outer surface of the case exposed to the outside of the housing, the heat generated by the voltage conversion means is directly transferred to the cooling means and radiated to the outside air, so that the cooling performance can be improved. Becomes

In the invention described in claim 4, claims 1 to 3 are provided.
In addition to the effect of the invention described in any one of 1, the heat generating portion of the voltage converting means is disposed inside the case exposed to the outside of the housing, so that the heat generating portion is on the low temperature outside air side in the case. Because of its position, the heat generated is radiated more effectively.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, for example, the output of a main battery (DC high voltage of about 300 to 400 V) as a voltage generating means applied to a wheel driving motor of an electric vehicle is supplied to a power source (12 V rated) of auxiliary machinery and the like. A DC-DC converter for converting into a DC low voltage for use as the above will be described.

FIG. 1 shows the configuration of the DC-DC converter according to this embodiment, and FIG. 2 shows AA of FIG.
FIG. In the figure, a DC-DC converter 1
Of the high voltage section case 2 and the main body section 10 which is attached to the opening 2a of the high voltage section case 2 as the housing shown by the broken line in FIG. 1 and in which the input line 3 and the output line 4 are introduced. A cooling section 20 as a cooling means attached to the outer surface of the main body section 10 located outside is provided.

The main body 10 has an opening on the upper surface in the drawing through which the input wire 3 is introduced, and a locking portion 11a for locking the opening 2a of the high-voltage case 2 is provided so as to project along the outer peripheral surface. And a hollow case 11 and a voltage conversion circuit 12 as a voltage conversion means for converting a high voltage input from the main battery via the input line 3 into a required DC low voltage and outputting it to the output line 4. Composed. For the case 11, for example, a case having an aluminum casting integrated structure is used. Further, a through hole 11 for introducing the output wire 4 into the inside is provided on the side surface below the locking portion 11a in the figure.
b is provided, and a waterproof structure is provided between the through hole 11b and the output line 4, so that, for example, a waterproof grommet 13 is attached. The voltage conversion circuit 12 is installed such that the heat generating portion 12a that generates heat during operation is located near the bottom surface (the surface on which the cooling portion 20 is attached to the outside) of the case 11. The circuit configuration of the voltage conversion circuit 12 is the same as the configuration of the voltage conversion circuit used in the conventional DC-DC converter, and a description thereof will be omitted here.

The case 11 and the high-voltage section case 2 are attached by inserting the case 11 from the outside into the opening 2a of the high-voltage section case 2 with the opening surface of the case 11 facing the high-voltage section case 2. The locking portion 11a of the case 11 is locked in the opening 2a. The positions of the plurality of screw holes 2b provided in the high voltage part case 2 along the opening 2a and the locking part 11a of the case 11
The screw 5 by aligning the positions of the multiple screw holes 11c provided on the
Fix with. At this time, the case 11 and the high-voltage part case 2 are in close contact with each other, and the waterproof property inside the high-voltage part case 2 is maintained.

The structure of an electric vehicle equipped with such a DC-DC converter 1 will be described with reference to the circuit structure of FIG. In the figure, the output of the main battery 51 mounted on the electric vehicle is input to the inverter 53, the DC-DC converter 1, and the air conditioner 55 via the junction box 52 and the input line 3. A motor 54 for driving wheels is connected to the inverter 53. The inverter 53, a part of the DC-DC converter 1 and the input line 3 are housed inside the high voltage section case 2. To the output line 4 connected to the DC-DC converter 1, a load 56 such as a head lamp or a tail lamp, a load 57 such as a wiper motor, a power window motor or a power steering pump, and a 12V battery 58 are connected. 4 (a) and 4 (b) show the arrangement of each component on the electric vehicle.

Next, the operation of the present embodiment will be described. The DC high voltage generated in the main battery 51 is input to the voltage conversion circuit 12 via the input line 3 and converted into a required DC low voltage. The converted DC low voltage is output to the main unit 10 via the output line.
Is output to the outside of. During this voltage conversion operation, the heat generated in the heating portion 12a of the voltage conversion circuit 12 is directly transferred from the bottom surface of the case 11 to the cooling portion 20. The cooling unit 20 is the high voltage unit case 2
Since it is located outside of and exposed to low temperature outside air,
The heat generated in a is efficiently dissipated. Further, inside the case 11, the waterproof grommet 13 prevents water and the like from entering from the outside to ensure waterproofness. High voltage part case 2
Even in the inside, moisture or the like does not enter from the outside due to the waterproof structure of the opening 2a and the locking portion 11a.

As described above, according to this embodiment, the portion for introducing the input line 3 into the main body portion 10 is located inside the high voltage portion case 2, and the portion for introducing the output line 4 into the main body portion 10 is large. The main body 10 is attached to the opening 2a of the high-voltage case 2 so that it is exposed to the outside of the high-voltage case 2, so that the output of the DC-DC converter 1 can be extracted as compared with the conventional built-in type. The structure is simple, and DC-DC compared with the conventional external type
The structure of the input part of the converter 1 is simplified. In addition, by arranging the open surface of the case 11 as an aluminum casting integrated structure inside the high voltage section case 2, only the through hole 11b for introducing the output wire 4 into the case 11 has a waterproof structure. It suffices to do so, and it is not necessary to waterproof the other parts of the case 11. Further, by mounting the DC-DC converter 1 from the outside of the high-voltage section case 2, the mounting work of the DC-DC converter 1 can be performed outside the high-voltage section case 2, and the workability is improved. Further, since the cooling unit 20 is directly attached to the outer bottom surface of the main body unit 10, the heat generated in the voltage conversion circuit 12 is directly transferred to the cooling unit 20 and radiated to the outside air, so that the cooling performance is improved. In addition, by disposing the heat generating part 12a inside the main body part 10 outside the high voltage part case 2, the heat generating part 12a is located on the low temperature outside air side in the main body part 10, so that the generated heat is more effective. Is radiated to.

In the present embodiment, in order to attach the main body 10 to the high voltage part case 2, the case 11 is provided with the locking part 11a and is fixed to the high voltage part case 2 with the screw 5. The mounting structure of the main body part 10 and the high voltage part case 2 is not limited to this. Further, although the case where a high DC voltage is input and converted into a low DC voltage has been described, the present invention is not limited to this, and a DC-DC converter that inputs an arbitrary DC voltage and converts it into a required DC voltage. Can be applied to.

[Brief description of drawings]

FIG. 1 is a diagram showing an appearance of an embodiment of the present invention.

FIG. 2 is a view showing a cross section taken along the line AA of FIG. 1 according to the embodiment.

FIG. 3 is a diagram showing a circuit configuration of the electric vehicle of the embodiment.

FIG. 4 is a diagram showing an arrangement of each configuration of the same embodiment.

[Explanation of symbols]

 1 DC-DC converter 2 High voltage case 2a Opening 3 Input wire 4 Output wire 5 Screw 10 Main body 11 Case 11a Locking part 11b Through hole 12 Voltage conversion circuit 12a Heating part 13 Waterproof grommet

Claims (4)

[Claims] 1. A case is attached to a case which internally includes an input line connected to a voltage generating means for generating a high-voltage DC voltage, and an input high voltage applied via the input line is converted into a low-voltage DC voltage. A DC-DC converter comprising a voltage converting means for converting and outputting to an output line in the case, wherein an opening is provided in the case, and the case has an introduction part of the input line of the case. A DC-DC converter, wherein the DC-DC converter is located inside and the introduction portion of the output line is exposed outside the housing and is attached to the opening. 2. The case has a locking portion that locks with the opening on an outer peripheral surface between the introduction portion of the input line and the introduction portion of the output line, and the locking portion is the casing. The DC-DC converter according to claim 1, wherein the DC-DC converter is attached to the opening from the outside of the body. 3. The DC-DC converter according to claim 1, wherein a cooling means is provided on the outer surface of the case exposed to the outside of the housing. 4. The DC-D according to claim 1, wherein the heat generating portion of the voltage converting means is arranged inside the case exposed to the outside of the housing.
C converter.