JP2009021500A - Electronic component unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To electrically insulate the fuse main body 41 of a temperature fuse 40 and a heat radiating member 10 without using an insulating tube in a motor control unit. <P>SOLUTION: In the motor control unit, a MOSFET 30, a temperature fuse 40 and a resin spacer 60 are housed inside the internal space 10a of the heat radiating member 10. Since the resin spacer 60 is provided with electric insulation parts 68a, 68b and 68c, even when the enclosure part 41a of the fuse main body 41 of the temperature fuse 40 is the same potential as one lead wire, the fuse main body 41 of the temperature fuse 40 and the heat radiating member 10 are electrically insulated without using the insulating tube. Since the electric insulation parts 68a, 68b and 68c are provided in the resin spacer 60, the number of components is not increased either. Since the need of a process of putting the insulating tube on the temperature fuse is eliminated, a manufacture cost is reduced. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic component unit in which damage due to abnormal heat generation of a heat generating electronic component such as a power transistor is protected by a thermal fuse.

Conventionally, in this type of electronic component unit, a field-effect transistor, a heat-dissipating member that dissipates heat in contact with the field-effect transistor, and a heat-receiving member that is housed in a recess of the heat-dissipating member. A thermal fuse that cuts off the power supply to the gate terminal of the field effect transistor when the heat dissipation member rises above a predetermined temperature, and the thermal fuse is closed in the recess so that the lead of the field effect transistor and the thermal fuse Resin spacers that respectively cover the lead wires are provided (for example, see Patent Document 1).
JP 2002-280514 A

  In the electronic component unit described above, a metal plate portion is provided on the back side of the field effect transistor, and the metal plate portion is in the same potential as the drain terminal, and the metal plate portion is brought into contact with the heat dissipation member. Then, the potential of the heat dissipation member is the same as that of the drain terminal of the field effect transistor.

  In this case, when a thermal fuse whose outer portion is made of metal and has the same potential as the lead wire is brought into contact with the heat radiating member, a field effect transistor is obtained as shown in the equivalent circuit of FIG. Since the gate terminal and the drain terminal of 1 are electrically short-circuited through the thermal fuse 2, the field effect transistor 1 does not operate normally.

  On the other hand, it is conceivable that the thermal fuse is covered with an insulating tube to electrically insulate between the thermal fuse and the heat dissipation member. In addition to the cost of the insulating tube itself, the thermal fuse is covered with the insulating tube. The cost is added and the cost is increased.

  An object of this invention is to provide the electronic component unit which electrically insulates between a thermal fuse and a thermal radiation member, without using an insulating tube in view of the said point.

In order to achieve the above object, in the present invention, an electronic component (30) having a heat generating part (32) that generates heat by energization and a lead wire (33) connected to the heat generating part (32),
A heat dissipating member (10) formed of a conductive material and dissipating heat in contact with the electronic component;
Out of the heat dissipating member, the heat dissipating member has an outer part (41a) made of a conductive material and is displaced from the contact surface with the heat generating part, and the heat dissipating member is heated to a predetermined temperature or more due to abnormal heat generation of the electronic component. A thermal fuse (40) having a fuse body (41) that cuts off power to the electronic component when raised, and a lead wire (42) connected to the fuse body;
An electrical insulation member (60) covering the lead wire (42) of the thermal fuse,
The electrical insulation member is provided with an electrical insulation portion (68a, 68b, 68c) disposed between the fuse body and the heat dissipation member and electrically insulating the fuse body and the heat dissipation member. This is the first feature.

  Thereby, even if the outer portion (41a) of the thermal fuse body is at the same potential as the lead wire, the thermal fuse and the heat radiating member are electrically insulated without using an insulating tube. Can do. Moreover, since the electrical insulation part is provided in the electrical insulation member, the number of parts does not increase.

  In the present invention, a second feature is that the heat radiating member is formed with a recess (10d) for accommodating the fuse body of the thermal fuse.

  Thereby, the heat from the heat radiating member is easily transmitted to the fuse body of the thermal fuse.

  Specifically, in the present invention, the electrical insulating portion is disposed on the heat generating portion (32) side with respect to the fuse main body in the concave portion, and an electrical connection is made between the fuse main body and the heat radiating member. The second feature is that a first electrical insulating portion (68a) for electrically insulating is provided.

  In the present invention, the electrical insulation portion includes a second electrical insulation portion (68b) disposed on the bottom side in the recess and electrically insulating the fuse body and the heat dissipation member. The third feature is that

  In the present invention, the electrical insulating portion is disposed on the opposite side to the heat generating portion (32) with respect to the fuse body in the recess, and electrically insulates the fuse body and the heat dissipation member. The fourth feature is that the third electrical insulating portion (68c) is provided.

In the present invention, the heat dissipation member is provided with a protrusion (10f) formed to protrude toward the fuse body,
A fifth feature is that a gap is provided between the protrusion (10f) and the fuse body (41).

  Thereby, the heat from the heat radiating member is easily transmitted to the fuse body.

Specifically, in the present invention, the electric insulation member is provided with two second electric insulation portions (68b), and the two second electric insulation portions are arranged at both ends of the fuse body. It is formed to protrude from the side toward the center,
A sixth feature is that the protruding portion (10f) is disposed between the tip ends of the two second electrical insulating portions.

  In the present invention, the electrical insulating portion is provided with a communication hole (68d) that communicates between the fuse body and the heat radiating member and transmits heat from the heat radiating member to the fuse body. Is the seventh feature.

  Thereby, the heat from the heat radiating member is easily transmitted to the fuse body.

In the present invention, the electrical insulating member is provided with a storage portion (61) surrounding the lead wire of the thermal fuse and an insertion hole (61a) for inserting the lead wire of the thermal fuse into the storage portion. ,
The insertion hole opens in an oblique direction with respect to the protruding direction of the third electrical insulating portion (68c),
An eighth feature is that the lead wire of the thermal fuse is inserted into the insertion hole in a state where the fuse body is displaced from the third electrical insulating portion.

  Thereby, even if the 3rd electrical insulation part is provided, the lead wire of a thermal fuse can be inserted in an insertion hole, without a fuse main body contacting a 3rd electrical insulation part.

  The ninth feature of the present invention is that the insertion hole communicates in an oblique direction toward the storage portion (61).

  Thereby, it becomes easy to insert the lead wire of the thermal fuse in the oblique direction with respect to the oblique direction.

  In addition, the code | symbol in the bracket | parenthesis of each means described in a claim and this column shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
FIG. 1 is a diagram showing a first embodiment in which an electronic component unit of the present invention is applied to an electronic component unit (hereinafter referred to as a motor control unit) that controls driving of a blower motor of a vehicle air conditioner. FIG. 1A is a front view showing the appearance of the motor control unit of the present embodiment, FIG. 1B is a view as seen from an arrow A in FIG. 1A, and FIG. 1C is B in FIG. An arrow view and FIG.1 (d) are C arrow views of FIG.1 (c).

  The motor control unit includes a heat radiating member 10 having an internal space 10a and a plurality of columnar heat radiating fins 10b extending downward. The motor control unit incorporates a field effect transistor 30 and the like to be described later in the internal space 10a. The internal space 10a is hermetically sealed. The motor control unit is assembled in a resin air conditioning case (not shown) that forms an air passage of the air conditioner, and the radiating fins 10b are cooled by the blown air from the blower.

  Here, the heat radiating member 10 is formed from a conductive material such as aluminum, and the heat radiating member 10 of the present embodiment is formed by integrally forming a portion forming the internal space 10a and the heat radiating fins 10b (for example, aluminum). (Integrated molding by die casting).

  2A is a view showing the inside of the internal space 10a of the heat dissipation member 10 with the lid member 20 removed, FIG. 2B is a cross-sectional view taken along the line AA in FIG. 2A, and FIG. It is a D arrow line view (electric circuit board 50 illustration omitted) of Drawing 2 (b).

  A field effect transistor (hereinafter referred to as MOSFET) 30 and a thermal fuse 40 are accommodated in the internal space 10 a of the heat radiating member 10.

  The MOSFET 30 (electronic component) is disposed so as to contact the bottom surface 10c of the heat radiating member 10, and is fixed to the heat radiating member 10 by fastening means (for example, screws) 30a. The MOSFET 30 includes a thin plate transistor body (that is, a heat generating portion) 32 that generates heat when energized. Three lead wires 33 arranged in parallel are connected to the transistor body 32. These lead wires 33 are formed in an L shape including an extending portion 33a extending from the side surface of the transistor body 32 along the bottom surface 10c of the heat radiating member 10 and an extending portion 33b extending upward from the tip of the extending portion 33a. Is formed.

  Here, a metal plate portion 30 b is disposed on the bottom surface 10 c side of the MOSFET 30, and the metal plate portion 30 b is in contact with the bottom surface 10 c of the heat dissipation member 10. The metal plate part 30b has the same potential as the drain terminal.

  An accommodation groove (recess) 10d for accommodating the fuse body 41 of the thermal fuse 40 is formed in the bottom surface 10c of the heat radiating member 10 directly below the extension 33a of the lead wire 33. The bottom surface 10c is provided at a position shifted from the contact surface of the MOSFET 30 with the transistor body 32.

  As shown in FIG. 3, the thermal fuse 40 includes two lead wires 42 extending from both ends of the fuse body 41 together with a fuse body 41 formed in a substantially cylindrical shape. One lead wire 42 of the two lead wires 42 is connected to the gate terminal, and the other lead wire 42 is connected to a drive circuit (not shown).

  The fuse body 41 includes an outer portion 41a that houses a temperature sensing portion (not shown), and the outer portion 41a is made of a metal material such as aluminum (that is, a conductive material). The outer portion 41 a has the same potential as one of the two lead wires 42.

  The temperature sensing part of the fuse body 41 opens between the gate terminal of the MOSFET 30 and the drive circuit when the heat dissipation member 10 rises to a predetermined temperature or more due to abnormal heat generation of the MOSFET 30. As a result, the fuse body 41 can cut off the energization from the drive circuit to the gate terminal of the MOSFET 30 along with the abnormal heat generation of the MOSFET 30.

  An electric circuit board 50 is disposed above the MOSFET 30, and each lead wire 33 of the MOSFET 30 and each lead wire 42 of the thermal fuse 40 are inserted into the electric circuit board 50 and soldered. ing. As a result, the MOSFET 30 and the thermal fuse 40 are connected to an electric circuit (not shown) formed on the electric circuit board 50. The thermal fuse 40 is connected to the gate terminal of the MOSFET 30.

  A resin spacer 60 is accommodated in the internal space 10a of the heat dissipation member 10, and the resin spacer 60 is integrally formed of an electrical insulating material (for example, resin). The resin spacer 60 has a function of closing and fixing the thermal fuse 40 in the accommodation groove 10 d, between the lead wires 33 and 42 of the MOSFET 30 and the thermal fuse 40, and between the lead wires 33 and 42 and the heat dissipation member 10. It also has the function of electrically insulating between.

  4A to 4E are views showing the resin spacer 60 alone. FIG. 4A is a front view, FIG. 4B is a plan view (top view), and FIG. FIG. 4D is a bottom view, FIG. 4D is a right side view, and FIG. 4E is a rear view.

  5A to 5D are views showing a state in which the lead wire 42 of the thermal fuse 40 is attached to the resin spacer 60, FIG. 5A is a front view, and FIG. 5C is a right side view, and FIG. 5D is a rear view.

  As shown in FIG. 4, the resin spacer 60 is formed with two first storage portions 61 surrounding each lead wire 42 of the thermal fuse 40 and three second storage portions 62 surrounding each lead wire 33 of the MOSFET 30. Has been. A partition wall 63 is formed between the first storage portion 61 and the second storage portion 62, and the lead wires 33 and 42 are insulated by the partition wall 63. Further, the outer peripheral walls 64 and 65 forming the outer peripheral surface of the resin spacer 60 insulate the lead wires 33 and 42 and the heat radiating member 10 from each other.

  A temporary fixing portion 66 that covers the lead wire 42 of the thermal fuse 40 is formed on the upper portion of the outer peripheral wall 64 of the resin spacer 60 and on the MOSFET 30 side. The temporary fixing portion 66 is a lead of the thermal fuse 40. It has a function of preventing the wire 42 from coming into contact with the heat radiating member 10 and a function of improving the pushability when the lead wire 42 is inserted into the electric circuit board 50 when the electric circuit board 50 is assembled. .

  In addition, on the lower side of the resin spacer 60 (that is, the bottom surface 10c side of the heat radiating member 10), electrical insulating portions 68a, 68b, and 68c are provided. The electrical insulating portions 68 a, 68 b and 68 c are disposed between the fuse body 41 and the heat dissipation member 10 to electrically insulate the fuse body 41 and the heat dissipation member 10.

  Specifically, the electric insulating portion 68a (first electric insulating portion) is formed so as to protrude from the lower outer peripheral wall 65 of the resin spacer 60, and the electric insulating portion 68a is shown in FIG. As shown, the fuse body 41 is disposed on the transistor body 32 side, and the distal end side of the electrical insulating portion 68a is located in the housing groove (recess) 10d.

  The two electrical insulation parts (second electrical insulation parts) 68b are formed on the bottom side of the housing groove (recessed part) 10d as shown in FIG. 2B (one electrical insulation part 68b is shown in the figure). Has been placed. As shown in FIG. 5, the two electrical insulating portions 68 b are formed so as to protrude from the longitudinal ends of the fuse body 41 to the central portion, and the two electrical insulating portions 68 b have gaps Z Is facing through.

  Here, as shown in FIG. 4C and FIG. 5B, the two electrical insulating portions 68b are respectively formed with communication holes 68d. The communication holes 68d are connected to the fuse body 41 and the heat dissipation member. 10 communicates with each other. The communication hole 68d is provided for transferring heat from the heat radiating member 10 to the fuse body 41.

  The electric insulating portion (second electric insulating portion) 68c is formed so as to protrude from the lower outer peripheral wall 65 of the resin spacer 60, and the electric insulating portion 68c is a fuse as shown in FIG. The main body 41 is disposed on the opposite side of the transistor main body 32, and the distal end side of the electric insulating portion 68c is located in the accommodation groove (recess) 10d.

  On the rear side of the resin spacer 60, as shown in FIGS. 4C and 5B, two groove portions 61b for receiving the two lead wires 42 of the thermal fuse 40 are provided. The two groove portions 61b are formed so as to extend in the horizontal direction shown in FIG. The two groove portions 61b are opened in the inclination direction (arrow Na) with respect to the protruding direction (vertical direction) of the electrical insulating portion 68c.

  In addition, the resin spacer 60 is provided with two insertion holes 61a for inserting the two lead wires 42 of the thermal fuse 40 into the first storage portion 61. The two insertion holes 61a are groove portions. It communicates with 61b. Thus, the two insertion holes 61a are opened in the inclination direction (arrow Na), respectively.

  As shown in FIGS. 4A and 4D, the two insertion holes 61a communicate with each other in the inclined direction (opposite to the arrow Na). An inclined surface 61c is formed in the insertion hole 61a so as to be inclined, and the inclined surface 61c accommodates the two lead wires 42 of the thermal fuse 40 from the insertion hole 61a as will be described later. It guides insertion to the part 61 side.

  Next, the assembly procedure of the motor control unit having the above configuration will be described with reference to FIGS.

  6 to 8 are views showing a procedure for assembling the thermal fuse 40 to the resin spacer 60. FIG. 6 (a) is a front view, FIG. 6 (b) is a bottom view, FIG. 6 (c) is a right side view, FIG. 5 (d) is a rear view. 7A is a right side view, and FIG. 7B is a rear view. FIG. 8A is the right side surface.

  FIG. 9 is a top view of the motor control unit with the lid member 20 removed, and FIG. 9A shows a state in which the MOSFET 30, the thermal fuse 40, and the electric circuit board 50 are not attached in the internal space 10a. Yes.

  First, the thermal fuse 40 is assembled to the resin spacer 60. Specifically, as shown in FIGS. 6A and 6B, the two lead wires 42 of the thermal fuse 40 are inserted into the two communication holes 68 d of the resin spacer 60.

  At this time, the fuse body 41 of the thermal fuse 40 is shifted downward from the electrical insulating portion 68c, and the insertion direction of the two lead wires 42 is the protruding direction of the electrical insulating portion 68c (that is, in FIG. 6A). (In the vertical direction). The two lead wires 42 are guided in the inclined direction by the inclined surface 61c and inserted into the first storage portion 61 as indicated by arrows.

  For this reason, as shown in FIGS. 7A and 7B, even if the two lead wires 42 of the thermal fuse 40 are inserted into the two communication holes 61d of the resin spacer 60, the fuse body 41 is electrically connected. It can be inserted without contacting the insulating portion 68c.

  Next, as shown in FIG. 8, the two lead wires 42 of the thermal fuse 40 are bent, and the two lead wires 42 are housed in the first housing portion 61 (see FIG. 5). Thereby, the assembly of the thermal fuse 40 to the resin spacer 60 is completed.

  In addition, a heat conductive material (for example, silicon grease) having an insulating property is filled in the accommodation groove 10 d of the heat radiating member 10. Furthermore, a heat conductive material is also filled in the communication holes 68d of the two electrical insulating portions 68b, and the gap between the fuse body 41 of the thermal fuse 40 and the housing groove 10d is eliminated. Thereby, the heat conduction from the heat radiating member 10 becomes good.

  Next, the resin spacer 60 assembled with the thermal fuse 40 is inserted into the internal space 10a of the heat radiating member 10 in the state of FIG. 9A, and the fuse body 41 of the thermal fuse 40 is inserted into the housing groove 10d of the heat radiating member 10. It accommodates and it will be in the state of FIG.9 (b).

  Next, the MOSFET 30 is inserted into the internal space 10 a, the bottom surface of the transistor body 32 of the MOSFET 30 is brought into contact with the bottom surface 10 c of the heat dissipation member 10, and the lead wire 33 of the MOSFET 30 is disposed in the second storage portion 62 of the resin spacer 60. Then, the extending portion 33 a of the lead wire 33 is placed on the bottom wall 65 of the resin spacer 60.

  Next, the MOSFET 30 is fastened to the heat dissipating member 10 with the screw 30a, and the state shown in FIG. As a result of this fastening, the extended portion 33a of the lead wire 33 of the MOSFET 30 and a part of the bottom surface of the transistor body 32 of the MOSFET 30 block the bottom wall 65 of the resin spacer 60. It is sandwiched between a part of the bottom surface of the main body 32 and the bottom surface 10 c of the heat radiating member 10 so as not to come out.

  Next, as shown in FIG. 2B, the electric circuit board 50 is inserted into the internal space 10a, and the lead wires 33 and 42 of the MOSFET 30 and the thermal fuse 40 are inserted into the electric circuit board 50 and soldered. To do. And the cover member 20 is attached to the heat radiating member 10, and the internal space 10a is sealed.

  According to the embodiment described above, since the resin spacer 60 is provided with the electrical insulating portions 68a, 68b, 68c, the outer portion 41a of the fuse body 41 of the thermal fuse 40 has the same potential as one of the lead wires. Even if it exists, in addition to electrically insulating a lead wire, without using an insulating tube, between the fuse main body 41 and the heat radiating member 10 can be electrically insulated. Furthermore, since the electrical insulating portions 68a, 68b, and 68c are provided on the resin spacer 60, the number of components does not increase.

  Since the motor control unit of the present embodiment does not use an insulating tube, a manufacturing cost can be reduced because a process of covering the temperature fuse with the insulating tube is not necessary when manufacturing the motor control unit.

  In the present embodiment, the fuse body 41 of the thermal fuse 40 is housed in the housing groove 10 d of the heat radiating member 10. For this reason, heat is transmitted to the fuse body 41 of the thermal fuse 40 from both sides of the housing groove 10d, so that the heat from the heat radiating member 10 is easily transmitted to the fuse body 41 of the thermal fuse 40.

  In the present embodiment, since the two electrical insulating portions 68b are each formed with the communication hole 68d, the heat from the heat radiating member 10 is easily transmitted to the fuse body 41 of the thermal fuse 40.

  Furthermore, in the present embodiment, as described above, the two insertion holes 61a of the resin spacer 60 are opened in the inclined direction with respect to the protruding direction of the electrical insulating portion 68c as described above. For this reason, the two lead wires 42 can be inserted in an inclined direction with respect to the protruding direction of the electrical insulating portion 68c. Therefore, the two lead wires 42 of the thermal fuse 40 can be inserted into the two communication holes 61 d of the resin spacer 60 in a state where the fuse body 41 of the thermal fuse 40 is shifted below the electrical insulating portion 68 c. .

  In the present embodiment, since the two insertion holes 61a have the inclined surface 61d (guide portion) on the first storage portion 61 side, the two lead wires 42 of the thermal fuse 40 can be easily inclined. Can be inserted into the insertion hole 61a.

(Second Embodiment)
In the first embodiment described above, the example in which the electrical insulating portion 68c is provided in the resin spacer 60 has been described. However, the present invention is not limited thereto, and the electrical insulating portion 68c may be deleted from the resin spacer 60.

  In this case, as shown in FIG. 10A, when assembling the thermal fuse 40 to the resin spacer 60, as shown in FIGS. 10A, 10B, and 10C, the two leads of the thermal fuse 40 are provided. The wire 42 can be inserted into the two communication holes 68d of the resin spacer 60 in the front-rear direction in the figure.

  Thereafter, as shown in FIG. 10D, the two lead wires 42 of the thermal fuse 40 are bent, and the two lead wires 42 are stored in the first storage portion 61. Thereby, the assembly of the thermal fuse 40 to the resin spacer 60 is completed.

(Other embodiments)
In the first embodiment, as shown in FIG. 11, the heat radiating member 10 may be provided with a protruding portion 10 f that is formed to protrude toward the fuse body 41. In this case, it is necessary to provide a gap between the protruding portion 10f and the fuse body 41 to electrically insulate the protruding portion 10f and the fuse body 41. Thereby, the heat from the heat radiating member 10 is easily transmitted to the fuse body 41.

  Here, the projecting portion 10f is disposed between the two electrical insulating portions 68b. Therefore, the operation of the thermal fuse 40 when the MOSFET 30 is abnormally heated can be ensured. Moreover, you may provide such a protrusion part 10f in the accommodation groove | channel 10d.

  In the first and second embodiments, the example using the MOSFET as the electronic component has been described. However, the present invention is not limited to this, and an electronic component other than the MOSFET may be used.

  In the first embodiment, the two insertion holes 61a are formed so as to communicate with the inclined direction with respect to the protruding direction of the electrical insulating portion 68c. However, the present invention is not limited to this, and the communication direction of the insertion hole 61a is The communication may be made in a direction other than the tilt direction.

  In the first embodiment, the outer portion 41a of the fuse body 41 of the thermal fuse 40 has the same potential as the one lead wire 42. However, the present invention is not limited to this, and the outer portion 41a is made of a conductive material. If it consists of, it may be electrically insulated with respect to the two lead wires 42.

  In this case, as described above, the fuse body 41 and the heat dissipation member 10 are electrically insulated from each other by the electrical insulation portions 68a, 68b, and 68c of the resin spacer 60. For this reason, for example, even when a lead wire of another electronic component is in contact with the outer portion 41a, an electrical short circuit may occur between the lead wire of the other electronic component and the heat dissipation member 10. Absent.

  Therefore, similarly to the above-described first embodiment, even when the heat dissipation member 10 is at the same potential as the drain terminal of the MOSFET 30, no failure occurs in other electronic components or the MOSFET 30.

  In the first embodiment, the accommodation groove 10d is formed in the bottom surface 10c of the heat radiating member 10 directly below the extended portion 33a of the lead wire 33 of the MOSFET 30. The housing groove 10d may be formed at a position shifted from the contact surface with the MOSFET 30 in the heat radiating member 10 without being limited to the one formed with 10d.

  For example, the accommodation groove 10d may be formed at a position farther from the MOSFET 30 than the portion directly below.

  In the first embodiment, the heat radiating member 10 is integrally formed with the portion forming the internal space 10a and the heat radiating fins 10b. For example, the heat radiating fins may be formed into a plurality of strips by extrusion, the case holding the MOSFET 30 is press-molded, and the heat radiating member 10 may be formed by combining the case and the fins of the heat radiating fins.

  In the first embodiment, the heat radiating member 10 has the housing groove 10d, and the thermal groove 40 is housed in the housing groove 10d. However, the housing groove 10d is abolished and is flush with the bottom surface 10c of the heat radiating member 10. A thermal fuse 40 may be installed in the.

  In the first and second embodiments, the example in which the electronic component unit of the present invention is applied to the motor control unit that controls the drive of the blower motor of the vehicle air conditioner has been described. You may apply the electronic component unit of this invention to.

BRIEF DESCRIPTION OF THE DRAWINGS It is an external view of the motor control unit which shows 1st Embodiment of this invention, (a) is a front view, (b) is A arrow view of (a), (c) is B arrow view of (b). (D) is a C arrow view of (c). (A) is the front which shows the internal space of the thermal radiation member of 1st Embodiment, (b) is AA sectional drawing in (a), (c) is D arrow directional view of (b). It is a figure which shows the thermal fuse single-piece | unit of 1st Embodiment. It is a figure which shows the resin spacer single-piece | unit of 1st Embodiment, (a) is a front view, (b) is a top view, (c) is a bottom view, (d) is a right side, (e) is a rear view. . It is a figure which shows the state by which each lead wire was attached to the resin spacer of 1st Embodiment, (a) is a front view, (b) is a bottom view, (c) is a right side surface, (d) is a rear view. is there. It is explanatory drawing explaining the procedure which attaches a thermal fuse to the resin spacer of 1st Embodiment, (a) is a front view, (b) is a bottom view, (c) is a right side, (d) is a rear view. is there. It is explanatory drawing explaining the procedure which attaches a thermal fuse to the resin spacer of 1st Embodiment, (a) is a right side surface, (b) is a rear view. It is a rear view for demonstrating the procedure which attaches a thermal fuse to the resin spacer of 1st Embodiment. It is explanatory drawing explaining the procedure which assembles | attaches a thermal fuse and MOSFET with respect to the heat radiating member of 1st Embodiment, (a) is a top view which shows the state before temperature fuse assembly | attachment, (b) is after temperature fuse assembly | attachment. FIG. 4C is a top view showing a state after the MOSFET is assembled. It is explanatory drawing explaining the procedure which attaches a thermal fuse to the resin spacer in 2nd Embodiment of this invention, (a)-(d) is a right side surface. It is a surface for demonstrating the procedure which attaches a thermal fuse to resin in the modification of this invention. It is an electric circuit diagram which shows the equivalent circuit of MOSFET.

Explanation of symbols

10 ... heat dissipation member, 10d ... receiving groove, 30 ... MOSFET,
33 ... MOSFET lead wire, 40 ... Thermal fuse,
42 ... Thermal fuse lead wire, 50 ... Electric circuit board,
60: Resin spacers, 68a, 68b, 68c: Electrical insulating parts.

Claims (10)

An electronic component (30) having a heat generating part (32) that generates heat by energization and a lead wire (33) connected to the heat generating part (32);
A heat dissipating member (10) formed of a conductive material and dissipating heat in contact with the electronic component;
Out of the heat dissipating member, the heat dissipating member has an outer portion (41a) made of a conductive material that is displaced from the contact surface with the heat generating unit, and the heat dissipating member is heated to a predetermined temperature or more due to abnormal heat generation of the electronic component. A thermal fuse (40) having a fuse body (41) that cuts off power to the electronic component when raised, and a lead wire (42) connected to the fuse body;
An electrical insulation member (60) covering the lead wire (42) of the thermal fuse,
The electrical insulation member is provided with an electrical insulation portion (68a, 68b, 68c) disposed between the fuse body and the heat dissipation member and electrically insulating the fuse body and the heat dissipation member. An electronic component unit characterized by that. 2. The electronic component unit according to claim 1, wherein the heat radiating member is formed with a recess (10 d) for storing a fuse body of the temperature fuse. The electrical insulating portion is disposed on the heat generating portion (32) side with respect to the fuse main body in the recess, and electrically insulates between the fuse main body and the heat radiating member. The electronic component unit according to claim 2, further comprising a portion (68 a). The electrical insulation portion includes a second electrical insulation portion (68b) disposed on the bottom side of the recess and electrically insulating the fuse body and the heat dissipation member. The electronic component unit according to claim 2 or 3. The electrical insulating part is disposed on the opposite side of the heat generating part (32) with respect to the fuse body in the recess, and electrically isolates the fuse body and the heat radiating member from each other. The electronic component unit according to any one of claims 2 to 4, further comprising an electrical insulating portion (68c). The heat dissipation member is provided with a protrusion (10f) formed to protrude toward the fuse body,
The electronic component unit according to claim 4, wherein a gap is provided between the protrusion (10f) and the fuse body (41). The electrical insulation member is provided with two second electrical insulation parts (68b),
The two second electrical insulating portions are formed so as to protrude from both end sides of the fuse body toward the central portion,
The electronic component unit according to claim 6, wherein the projecting portion (10 f) is disposed between tip ends of the two second electrical insulating portions. The electrical insulating portion is provided with a communication hole (68d) that communicates between the fuse body and the heat radiating member and transmits heat from the heat radiating member to the fuse body. The electronic component unit according to claim 1. The electrical insulating member is provided with a storage portion (61) surrounding the lead wire of the thermal fuse, and an insertion hole (61a) for inserting the lead wire of the thermal fuse into the storage portion,
The insertion hole opens in an oblique direction with respect to the protruding direction of the third electrical insulating portion (68c),
The lead wire of the thermal fuse is inserted into the insertion hole in a state where the fuse body is displaced from the third electrical insulating portion. The electronic component unit according to one. The electronic component unit according to claim 9, wherein the insertion hole communicates in the oblique direction toward the storage portion (61).

Images