JP2002217574A - Power converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power converter, having a small size and being light- weight and having proper heat radiating properties, at low cost. SOLUTION: A circuit board 1 having a component of a power converter circuit for converting an input from a power source to desired power level to supply the power to a load of the output side, an input terminal connected with the power source, an output terminal connected to the load and the like, is contained in a body 3 which is opened at one surface. The one surface side of the body 3 is covered with a cover. A component (heating component) 2, having a large heating amount, is disposed at the front surface side of the board 1. A cutout 1a is provided at a part of the portion to be superposed with the component 2 on the board 1, and a radiating part 4 projected so as to be in close contact with the component 2 is continuously integrally projected from the opposed surface of the board 1 of the body 3. The cutout part 1a is provided at a region, except at the connector of the board 1 to the component 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power converter for converting an input from a power supply into a desired power and supplying the desired power to a load on an output side.

[0002]

2. Description of the Related Art In general, components of a power converter that use a large amount of heat (hereinafter, referred to as heat generating components) such as a transformer and a switching element are used. And the problem that the temperature of the heat-generating component becomes high has become remarkable. Therefore, in the conventional power converter, in order to reduce the size of the heat-generating component while taking measures to dissipate the heat-generating component, as shown in FIG. 7, the heat-generating component 2 is placed on the surface (the upper surface in FIG. And a circuit board 1 on which a surface-mounted component is mounted on the back side, and a body 3 having an open side and a cover (not shown) covered on the one side of the body 3. In general, the case is fixed so as to have a specified distance from the wall 3a, and the case is filled with a heat-radiating resin having high thermal conductivity. That is, the conventional power converter is configured to radiate the heat generated by the heat-generating component 2 to the outside of the case through the resin filled in the case and the case.

[0003]

However, in the conventional power converter, sufficient heat radiation cannot be obtained, and the heat-generating components 2
There was a problem that the temperature of the device was too high. That is, since the circuit board 1 and the heat-generating component 2 are covered with the resin in the case, it is difficult for the heat generated in the heat-generating component 2 to be radiated to the outside of the case. In order to prevent heat damage, it is necessary to use components with a large rating, and the board area of the circuit board 1 on which the components are mounted increases, resulting in an increase in the size of the power converter. There was a problem that. Further, in the conventional power converter, it is necessary to fill the case with a resin for heat dissipation, which is disadvantageous in terms of weight reduction and cost reduction.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a power conversion device which can be reduced in size and weight and cost, and has excellent heat dissipation.

[0005]

According to a first aspect of the present invention, there is provided a power conversion circuit for converting an input from a power supply into a desired power and supplying the desired power to a load on an output side. A power converter including a board on which at least a part of a component constituting a circuit is mounted, and a case in which the board is housed, wherein a part of a portion of the board that overlaps a component having a large calorific value. A notch portion is provided in the case, and a heat radiating portion for radiating heat generated by a component having a large heat value to the outside of the case projects continuously and integrally from a surface of the case facing the substrate so as to pass through the notch portion. Since the heat generated by the components having a large heat value can be radiated from the case to the outside of the case through a heat radiating portion projecting integrally from the case. It is possible to improve the heat dissipation without using a separate member and without filling the conventional resin for heat dissipation in a case so, it is possible to reduce the size and weight and cost.

According to a second aspect of the present invention, in the first aspect of the present invention, a heat conductive member made of a material having high thermal conductivity is sandwiched between the component having a large heat value and the heat radiating portion. It is possible to efficiently dissipate the heat generated by the components that generate a large amount of heat, and if a material having electrical insulation is used as the heat conducting member, regardless of the materials of the component and the case that generate a large amount of heat, Electrical insulation between the component and the case can be ensured.

According to a third aspect of the present invention, in the first aspect of the invention, the case has fins formed on an outer surface side of a portion corresponding to the heat radiating portion, so that heat radiation can be further improved. Thus, the weight can be further reduced.

According to a fourth aspect of the present invention, in the first aspect of the present invention, since the notch is provided near the side wall of the case, the notch is formed in a shape in which the side wall of the case is opened. By providing the heat radiating portion across the side of the case facing the substrate and the side wall of the case, it is possible to increase the cross-sectional area of the heat radiating path of the heat generated by the component having a large amount of generated heat, Heat dissipation is further improved.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, a heat conductive member made of a material having high heat conductivity is sandwiched between the heat radiating portion and the side wall and the component having a large heat value. Therefore, it is possible to efficiently radiate the heat generated by the components having a large heat value, and to use a material having an electrical insulating property as a heat conducting member, for each of the component having a large heat value and the case. The electrical insulation between the component and the case can be ensured regardless of the material.

According to a sixth aspect of the present invention, in the invention of the fourth aspect, the case has fins formed on an outer surface side of a portion corresponding to the heat radiating portion or on an outer surface side of the side wall, so that heat dissipation is further improved. Can be improved,
It is possible to further reduce the weight.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) As shown in FIG. 1, a power converter according to the present embodiment has a circuit board 1 composed of a printed board, which is a synthetic resin molded product (see FIG. 1A). The upper surface (upper surface) is housed in a case composed of an open body 3 and a cover of a synthetic resin molded product covered on the one surface side of the body 3. In this embodiment, components of a power conversion circuit including a discharge lamp lighting circuit that converts an input from a power supply into a desired power and supplies the power to a discharge lamp as a load on the output side, Input terminal to be connected,
Although an output terminal or the like to which the discharge lamp is connected is mounted, only components 2 having a large amount of heat (hereinafter, referred to as heat generating components) are shown, and portions that do not particularly affect the gist of the present embodiment are shown. Are omitted from the drawings and reference numerals. Further, the case may be made of metal in order to enhance the heat radiation efficiency.

In the present embodiment, the heat-generating component 2 is disposed on the front surface side (the upper surface side in FIG. 1) of the circuit board 1, and a cutout portion 1a is provided in a part of the circuit board 1 that overlaps the heat-generating component 2. And the circuit board 1 in the body 3
It is characterized in that a heat radiating portion 4 protruding from the surface opposite to the heat generating component 2 so as to be in close contact with the heat generating component 2 is continuously and integrally provided. Here, the cutout portion 1 a is provided in a portion of the circuit board 1 except for a connection portion with the heat generating component 2. In addition, the radiator 4
Is set such that the distal end surface of the heat radiating portion 4 is in close contact with the heat generating component 2 in a state where the circuit board 1 is fixed to the body 3.

Thus, in the power converter of the present embodiment, the heat of the heat-generating component 2 can be radiated to the outside of the case via the heat-radiating portion 4 continuously and integrally provided from the bottom wall 3a of the body 3. (The heat can be dissipated in the direction of arrow C1 in FIG. 1 (a)), so that the heat dissipating property can be improved without filling the case with a heat dissipating resin and using a separate member as in the related art. Thus, size, weight, and cost can be reduced.

(Embodiment 2) The basic configuration of a power converter according to the present embodiment is substantially the same as that of Embodiment 1, and as shown in FIG. It is characterized in that a heat radiating sheet 5 made of a material having high electrical insulation and high thermal conductivity is sandwiched. Here, the heat radiation sheet 5 constitutes a heat conduction member. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Thus, in the power converter of the present embodiment, similarly to the first embodiment, the heat of the heat-generating component 2 can be radiated to the outside of the case via the radiator 4 of the body 3 (see FIG. a) Heat can be dissipated in the direction of arrow C1 in FIG. 2), so that heat dissipation can be improved without filling the case with resin for heat dissipation as in the conventional case. Since the weight and cost can be easily reduced as compared with the resin filled in the case, the size and weight and the cost can be reduced.

In this embodiment, since the heat radiating sheet 5 having high electric insulation and high thermal conductivity is sandwiched between the heat generating component 2 and the heat radiating portion 4 of the body 3, the heat generating component 2
Can efficiently dissipate the heat generated by the heat generating component 2 and the electric insulating property between the heat generating component 2 and the body 3 irrespective of the materials of the heat generating component 2 and the case 3. Even if 2 is a non-insulating element, the heat of the heat-generating component 2 can be radiated through the radiator 4 of the case 3.

(Embodiment 3) The basic configuration of a power converter according to the present embodiment is substantially the same as that of Embodiment 1, and as shown in FIG. It is characterized in that fins 4a having an increased heat radiation area are provided. Here, the fins 4 a are formed by providing a plurality of cut grooves 4 b on the outer surface of the body 3 from a portion corresponding to the heat radiating portion 4 to the heat generating component 2 side. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

However, in the power converter of the present embodiment, similarly to the first embodiment, the heat of the heat-generating component 2 is transferred from the bottom wall 3a of the body 3 to the case via the heat-radiating portion 4 which is continuously and integrally provided. The heat can be radiated to the outside (the heat can be radiated in the direction of arrow C1 in FIG. 3A), so that a separate member is not used without filling the case with the heat-radiating resin as in the conventional case. Therefore, heat dissipation can be improved, and reduction in size and weight and cost can be achieved.
Further, in the present embodiment, since the fins 4a are formed by providing the above-described cut grooves 4b in the heat radiating portion 4 of the body 3, the heat radiating properties can be further improved and the weight can be further reduced. .

(Embodiment 4) The basic configuration of a power converter according to the present embodiment is substantially the same as that of Embodiment 1, and as shown in FIG. The feature is that it is provided in the vicinity. Here, the cutout portion 1a is formed in a shape in which the side wall 3b side of the body 3 is opened, and the heat radiating portion 4 is provided across the bottom wall 3a of the body 3 and the side wall 3b of the body 3. In addition,
The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

Thus, in the power converter of the present embodiment, similarly to the first embodiment, the heat of the heat generating component 2 is radiated from the body 3 to the outside of the case via the heat radiating portion 4 which is continuously and integrally provided. Therefore, heat dissipation can be improved without filling the case with a heat dissipation resin and using a separate member as in the related art, and reduction in size, weight, and cost can be achieved. Moreover, the heat of the heat-generating component 2 can be radiated through the bottom wall 3a and the side wall 3b of the body 3 (the heat can be radiated in the directions of arrows C1 and C2 in FIG. 4A). The cross-sectional area of the heat dissipation path for dissipating heat can be increased, and the heat dissipation can be further improved as compared with the first embodiment.

(Embodiment 5) The basic configuration of a power converter according to this embodiment is substantially the same as that of Embodiment 4, and as shown in FIG. It is characterized in that a heat radiating sheet 5 made of a material having high electrical insulation and high thermal conductivity is sandwiched between the side wall 3b. Here, the heat dissipation sheet 5 constitutes a heat conduction member. Note that the same components as those in the fourth embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the power converter of the present embodiment, as in the fourth embodiment, the heat of the heat-generating component 2 is radiated to the outside of the case through the heat radiating portion 4 of the body 3 and the side wall 3b of the body 3. (Arrow C1 in FIG. 5A)
And heat can be dissipated in the direction of C2), so that heat dissipation can be improved without filling the case with resin for heat dissipation as in the conventional case, and the heat dissipation sheet 5 is filled in the case in the conventional configuration. Since the weight and cost can be easily reduced as compared with the resin used, the size and weight and the cost can be reduced.

In this embodiment, the heat radiating sheet 5 having high electric insulation and high thermal conductivity is sandwiched between the heat generating component 2 and the heat radiating portion 4 of the body 3 and the side wall 3b of the body 3. In addition, the heat generated by the heat-generating component 2 can be efficiently radiated, and electrical insulation between the heat-generating component 2 and the body 3 can be ensured regardless of the materials of the heat-generating component 2 and the body 3. Thus, even if the heat-generating component 2 is a non-insulating element, the heat of the heat-generating component 2 can be radiated through the heat radiating portion 4 of the body 3. When mounting the heat-generating component 2 on the circuit board 1, the heat-radiating sheet 5 is pressed by the corner portion of the heat-generating component 2, and the corner of the heat-generating component 2, the distal end surface of the heat-radiating portion 4 of the body 3, and the body 3 Since the heat radiation sheet 5 is sandwiched between the heat radiation sheet 5 and the side wall 3b, the heat radiation sheet 5 can be prevented from being shifted, and the reliability is improved.

(Embodiment 6) The basic structure of a power converter according to this embodiment is substantially the same as that of Embodiment 4, and as shown in FIG. It is characterized in that fins 4a are provided in the vicinity, and the radiating area is enlarged on the outer surface side of the radiating portion 4 provided in the body 3. Here, the cutout portion 1a is formed in a shape in which the side wall 3b side of the body 3 is opened.
Is provided across the surface of the bottom wall 3 a of the body 3 facing the circuit board 1 and the side wall 3 b of the body 3. Also,
The fins 4 a are formed by providing a plurality of cut grooves 4 b on the outer surface of the body 3 from a portion corresponding to the heat radiating portion 4 to the heat generating component 2 side. Note that the same components as those in the fourth embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the power converter of the present embodiment, as in the fourth embodiment, the heat of the heat-generating component 2 is radiated to the outside of the case via the heat radiating portion 4 of the body 3 and the side wall 3b of the body 3. (Arrow C1 in FIG. 6A)
And heat can be dissipated in the direction of C2), so that there is no need to fill the case with a heat-dissipating resin as in the conventional case, and it is possible to reduce the size and weight, reduce the cost, and improve the heat dissipation. In this embodiment,
Since the fins 4a are formed by providing the above-described cut grooves 4b in the heat radiating portion 4 of the body 3, the heat radiation can be further improved and the weight can be further reduced. Note that the fins 4a may be formed by providing cut-away grooves in the side walls 3b of the body 3 corresponding to the heat radiating portions 4.

[0026]

According to the first aspect of the present invention, a power conversion circuit for converting an input from a power supply into a desired power and supplying the power to a load on an output side, and at least a part of components constituting the power conversion circuit are mounted. Power conversion device, comprising: a cutout portion provided in a portion of the substrate that overlaps a component that generates a large amount of heat; A heat radiating portion for radiating the heat generated by the components to the outside of the case is continuously and integrally protruded from a surface of the case facing the substrate so as to pass through the cutout portion, and has a large heat generation amount. The heat generated by the components can be radiated from the case to the outside of the case through a heat radiating portion continuously and integrally provided from the case, so that the case does not need to be filled with a resin for heat dissipation as in the conventional case. It is possible to improve the heat dissipation without using a separate member, there is an effect that it is possible to reduce the size and weight and cost.

According to a second aspect of the present invention, in the first aspect of the present invention, a heat conductive member made of a material having high thermal conductivity is sandwiched between the component having a large heat value and the heat radiating portion. This has the effect of efficiently dissipating the heat generated by the components that generate a large amount of heat.
If a material having electrical insulation is used as the heat conducting member, electrical insulation between the component and the case can be ensured regardless of the materials of the component and the case that generate a large amount of heat. effective.

According to a third aspect of the present invention, in the first aspect of the present invention, the case has fins formed on an outer surface side of a portion corresponding to the heat radiating portion, so that heat radiation can be further improved. This has the effect that the weight can be further reduced.

According to a fourth aspect of the present invention, in the first aspect of the present invention, since the notch is provided near the side wall of the case, the notch is formed in a shape in which the side wall of the case is opened. By providing the heat radiating portion across the side of the case facing the substrate and the side wall of the case, it is possible to increase the cross-sectional area of the heat radiating path of the heat generated by the component having a large amount of generated heat, There is an effect that the heat dissipation is further improved.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, a heat conductive member made of a material having high heat conductivity is sandwiched between the heat radiating portion and the side wall and the component having a large calorific value. Therefore, there is an effect that the heat generated by the component having a large heat value can be efficiently radiated, and the component having a large heat value can be obtained by using an electrically insulating material as a heat conducting member. There is an effect that electrical insulation between the component and the case can be ensured regardless of the material of the case.

According to a sixth aspect of the present invention, in the fourth aspect of the present invention, the case has a fin formed on an outer surface side of a portion corresponding to the heat radiating portion or an outer surface side of the side wall. Can be improved,
There is an effect that the weight can be further reduced.

[Brief description of the drawings]

FIGS. 1A and 1B show a first embodiment, in which FIG.
(B) is the principal part schematic perspective view which fractured partially.

FIGS. 2A and 2B show a second embodiment, in which FIG.
(B) is the principal part schematic perspective view which fractured partially.

FIGS. 3A and 3B show a third embodiment, in which FIG.
(B) is an enlarged view of the main part A of (a).

FIGS. 4A and 4B show a fourth embodiment, in which FIG.
(B) is the principal part schematic perspective view which fractured partially.

5A and 5B show a fifth embodiment, in which FIG.
(B) is the principal part schematic perspective view which fractured partially.

6A and 6B show a sixth embodiment, in which FIG.
(B) is an enlarged view of a main part B of (a).

7A and 7B show a conventional example, in which FIG.
(B) is the principal part schematic perspective view which fractured partially.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Circuit board 1a Notch part 2 Component part (heat generation part) 3 Body 4 Heat radiation part

Claims (6)

[Claims] 1. A power conversion circuit for converting an input from a power supply into a desired power and supplying it to a load on an output side, a board on which at least a part of components constituting the power conversion circuit is mounted, and the board And a case in which a notch is provided in a part of the substrate that overlaps with a component that generates a large amount of heat, and the heat generated by the component that generates a large amount of heat is provided. A power converter wherein a heat radiating portion for radiating heat to the outside of the case is continuously and integrally protruded from a surface of the case facing the substrate so as to pass through the cutout portion. 2. The power converter according to claim 1, wherein a heat conducting member made of a material having high heat conductivity is sandwiched between the component having a large heat value and the heat radiating portion. 3. The power converter according to claim 1, wherein the case has a fin formed on an outer surface of a portion corresponding to the heat radiating portion. 4. The power converter according to claim 1, wherein the notch is provided near a side wall of the case. 5. A heat conductive member made of a material having high heat conductivity is sandwiched between the heat radiating portion and the side wall and the component having a large heat value.
The power converter according to any one of the preceding claims. 6. The power converter according to claim 4, wherein the case has fins formed on an outer surface side of a portion corresponding to the heat radiating portion or an outer surface side of the side wall.