JP2003174128A - Actuator drive controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator drive controller which efficiently dissipates heat of a drive element. <P>SOLUTION: In the actuator drive controller having the drive element 11 for driving the actuator, a substrate 12 on which the drive element 11 is loaded, a case 13 for housing the substrate 12, and a heat sink 14 for dissipating the heat generated from the drive element 11 to the outside of the case, the heat sink 14 is in contact with the upper face of the drive element 11, and the case 13 is equal to or more than the drive element 11 and the substrate 12 in coefficient of thermal expansion. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator drive control device that requires heat radiation.

[0002]

2. Description of the Related Art Conventionally, there has been a drive controller for controlling actuators such as fuel pumps and fuel injection valves for automobiles.

FIG. 6 is a sectional view of a conventional actuator drive control device. It is the drive element 61 that controls the drive of the actuator. The driving element 61 is a semiconductor element, and is bonded to the substrate 62 together with a resistor and the like (not shown). The actuator itself is entirely controlled by the drive element 61.
Done in. The substrate 62 also includes a circuit that protects the driving element 61, a circuit that suppresses voltage fluctuations, and the like.

The drive element 61 and the substrate 62 are housed in a case 63. The case 63 is made of resin. Drive element 6
A resin molding material 64 is filled between the case 1 and the case 63. Since the molding material 64 is filled in to ensure waterproofness, the driving element 61 and the substrate 62 are molded with the molding material 64.
It is completely wrapped in.

The drive element 61 generates heat according to the consumed current. The generated heat is transferred to the case 63 via the molding material 64 and is radiated at the surface in contact with the outside air.

[0006]

However, the molding material 6
Both 4 and case 63 are made of resin and have poor thermal conductivity. FIG. 5 is a graph showing a temperature change of the actuator drive control device. The horizontal axis represents drive control time, that is, energization time, and the vertical axis represents temperature. Graph 51 is shown in FIG.
4 shows the temperature change of the conventional actuator drive control device shown in FIG. As the graph 51 shows, the temperature of the drive control device rises with time. When the actuator is controlled by duty drive, this temperature change becomes larger. If the temperature becomes higher than a certain value, it may cause malfunction or failure of the driving element 61.

Therefore, an object of the present invention is to provide an actuator drive control device that efficiently dissipates the heat of a drive element.

[0008]

To achieve the above object, the present invention provides a drive element for driving an actuator,
In an actuator drive control device having a substrate on which the drive element is mounted, a case for accommodating the substrate, and a heat radiating plate for radiating heat generated by the drive element to the outside of the case, the drive element is provided on the upper surface of the drive element. The feature is that the heat sink is in contact.

Further, it has a drive element for driving the actuator, a substrate on which the drive element is mounted, a case for accommodating the substrate, and a heat dissipation plate for radiating heat generated by the drive element to the outside of the case. The actuator drive control device is configured to have an elastic body that presses the drive element against the heat dissipation plate by elastic force.

Further, it has a drive element for driving the actuator, a substrate on which the drive element is mounted, a case for accommodating the substrate, and a heat radiating plate for radiating heat generated by the drive element to the outside of the case. In the actuator drive control device, a clearance is provided between the drive element and the heat dissipation plate, and the clearance has a semi-fluid heat transfer substance.

Further, the coefficient of thermal expansion of the case is equal to or higher than the coefficient of thermal expansion of the drive element or the substrate, and the drive element drives the actuator by turning on / off in a predetermined cycle. The actuator drive control device may be a drive element, the actuator drive control device may be a fuel pump drive control device, or the actuator drive control device may be a fuel injection valve drive control device.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an actuator drive control device of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of the first embodiment of the present invention. The drive element 11 is a semiconductor element, and the drive element 11 controls all of the actuators. The substrate 12 is formed with the drive element 11 as well as a circuit for protecting the drive element 11 and a circuit for suppressing voltage fluctuation.

The case 13 is made of resin and has a size capable of accommodating the drive element 11 and the substrate 12. The substrate 12 is fixed to the case 13 with screws or the like not shown. Unlike the conventional example, a resin molding material that wraps the entire driving element 11 is not used.

The heat radiating plate 14 radiates the heat generated by the driving element 11 to the outside air, and at the same time serves as a cover for the case 13. This is made of metal having a high thermal conductivity and is attached so as to come into contact with the upper surface of the driving element 11. Between the case 13 and the heat sink 14 is waterproofed by a seal rubber (not shown). By mounting the heat dissipation plate 14 so as to come into contact with the upper surface of the drive element 11 in this manner, the heat generated by the drive element 11 can be quickly released to the outside air.

Even when the heat dissipation plate 14 is used to dissipate heat, the heat of the driving element 11 is transmitted from the heat dissipation plate 14 to the case 13. At this time, case 13
If the coefficient of thermal expansion of the driving element 11 or the substrate 12 is higher than the coefficient of thermal expansion of, the driving element 11 is pressed and stress is applied. Therefore, the coefficient of thermal expansion of the case 13 is determined by the drive element 1
1 or the thermal expansion coefficient of the substrate 12 is preferably equal to or higher than that.

FIG. 2 is a sectional view showing the state of thermal expansion of the case 13. (A) shows the state at room temperature,
(B) shows a state of thermal expansion at high temperature. Figure 2
In (a), since the thermal expansion does not occur, the driving element 1
1 and the heat sink 14 are in contact with each other. As shown in FIG. 2 (b), this is because the heat generated by the driving element 11 causes the case 13 to move to
Thermal expansion occurs in the direction of the arrow (b). The heat sink 14 is lifted in the direction of the arrow as the case 13 expands,
A clearance 21 is generated between the drive element 11 and the drive element 11.

When the clearance 21 between the driving element 11 and the heat dissipation plate 14 is generated, the thermal conductivity deteriorates, and the driving element 1
There is an inconvenience that the temperature of 1 rises. Therefore, the following embodiment can be considered.

FIG. 3 is a sectional view of the second embodiment of the present invention. Drive element 11, substrate 12, case 13, and heat sink 1
4 is the same as the embodiment of FIG. Between the case 13 and the heat sink 14 is waterproofed by a seal rubber (not shown). In this embodiment, a slight clearance is provided in advance between the drive element 11 and the heat dissipation plate 14. Then, the clearance is filled with silicon grease 31. Silicone grease 31 is a heat transfer material having a semi-fluidity. Due to the thermal expansion, the driving element 11
Even when the clearance between the heat dissipation plate 14 and the heat dissipation plate 14 increases, the heat of the driving element 11 is transferred to the heat dissipation plate 14 through the silicon grease 31.
Since it can be transmitted to, heat can be efficiently dissipated.

FIG. 4 is a sectional view of the third embodiment of the present invention. Drive element 11, substrate 12, case 13, and heat sink 1
4 is the same as that of the first embodiment. In addition, a waterproof treatment is applied between the case 13 and the heat radiating plate 14 by a seal rubber (not shown), as in the first embodiment.

In FIG. 4, leaf springs 41 and 4 are provided under the substrate 12.
I have installed 1. The leaf springs 41, 41 press the drive element 11 against the heat radiating plate 14, so that heat is efficiently radiated. Further, by using the leaf springs 41, 41, even if the case 13 expands in the direction shown by the arrow in FIG. 2B due to heat, the drive element 11 is constantly pressed against the heat dissipation plate 14 by the elastic force of the leaf spring 41. Keep going. In FIG. 4, the leaf springs 41, 41 are used to press the drive element 11 against the heat dissipation plate 14, but the present invention is not limited to this, and the drive element 11 is applied to the heat dissipation plate 14 by force. It only needs to be pressed.

A graph 52 showing the temperature changes of these examples is a graph 52 in FIG. As shown in graph 52,
The embodiment of the present invention can radiate the heat of the driving element more efficiently than the conventional driving control device as shown in FIG.

[0022]

As described above, according to the present invention, a drive element for driving an actuator, a substrate on which the drive element is mounted, a case for accommodating the substrate, and heat generated by the drive element are external to the case. In the actuator drive control device having a heat radiating plate that discharges heat to the drive element, the heat radiating plate is in contact with the upper surface of the drive element, so that the heat generated by the drive element can be efficiently discharged to the outside.

By making the thermal expansion coefficient of the case equal to or higher than the thermal expansion coefficient of the drive element or the substrate, stress on the drive element can be prevented.

A drive element for driving the actuator, a substrate on which the drive element is mounted, a case for housing the substrate, a heat dissipation plate for radiating heat generated by the drive element to the outside of the case, and the drive element With the configuration including an elastic body that is pressed against the heat dissipation plate by elastic force, heat dissipation of the drive element can be efficiently performed.

Actuator drive having a drive element for driving the actuator, a substrate on which the drive element is mounted, a case for accommodating the substrate, and a heat dissipation plate for radiating heat generated by the drive element to the outside of the case In the control device, a clearance is provided between the drive element and the heat dissipation plate, and the clearance contains a semi-fluid heat transfer substance, so that heat can be dissipated even when there is a clearance between the drive element and the heat dissipation plate.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state of thermal expansion of a case,
(A) shows the appearance at room temperature, and (b) shows the appearance of expansion at high temperature.

FIG. 3 is a sectional view of a second embodiment of the present invention.

FIG. 4 is a sectional view of a third embodiment of the present invention.

FIG. 5 is a graph showing a temperature change of the actuator driving device.

FIG. 6 is a sectional view of a conventional actuator driving device.

[Explanation of symbols]

11 Drive element 12 substrates 13 cases 14 Heat sink 31 Silicone grease

Claims (7)

[Claims] 1. A drive element for driving an actuator,
In an actuator drive control device having a substrate on which the drive element is mounted, a case for accommodating the substrate, and a heat radiating plate for radiating heat generated by the drive element to the outside of the case, the drive element is provided on the upper surface of the drive element. An actuator drive control device characterized in that a heat sink is in contact. 2. The actuator drive control device according to claim 1, wherein the coefficient of thermal expansion of the case is equal to or higher than the coefficient of thermal expansion of the drive element and the substrate. 3. A drive element for driving the actuator,
A board on which the drive element is mounted, a case that accommodates the board, a heat dissipation plate that radiates heat generated by the drive element to the outside of the case, and an elastic body that presses the drive element against the heat dissipation plate by elastic force. An actuator drive control device comprising: 4. A drive element for driving the actuator,
In an actuator drive control device including a substrate on which the drive element is mounted, a case that accommodates the substrate, and a heat dissipation plate that radiates heat generated by the drive element to the outside of the case, between the drive element and the heat dissipation plate. An actuator drive control device, characterized in that a clearance is provided in the clearance, and the clearance contains a semi-fluid heat transfer substance. 5. The actuator drive control device according to claim 1, wherein the drive element is a drive element that drives an actuator by turning on / off in a predetermined cycle. 6. The actuator drive controller according to claim 1, wherein the actuator drive controller is a fuel pump drive controller. 7. The actuator drive control device according to claim 1, wherein the actuator drive control device is a drive control device for a fuel injection valve.