JP5174413B2 - Control device - Google Patents

Description

  The present invention relates to an engine control device.

  Conventionally, a control device for an internal combustion engine generally has a waterproof structure from the viewpoint of waterproofness, dustproofing, and rustproofing. The main structures of the waterproof structure are a structure in which a molded elastic member is sandwiched between a case and a cover to give a tight force and waterproof, and a structure in which a liquid waterproof adhesive is applied and cured to waterproof. Or the case which accommodates a board | substrate and a connector is made into cup shape, and after installing a board | substrate, the waterproofing gel agent etc. are filled and the waterproof structure is constructed | assembled.

  However, in the former structure, it is necessary to ensure a surface state where the waterproofing adhesive can be reliably bonded, and management such as special cleaning is required. In addition, since there is an air layer inside, there is a problem of affecting the harness side connected to the control device due to changes in internal pressure in the control device due to height difference or temperature difference, and the control device itself is abrupt. When an environmental change is received, there is a problem that deformation or pressure due to a change in internal pressure is applied to the waterproof structure portion to reduce reliability.

  Further, in the latter structure, it is necessary to form a case for housing the substrate in a cup shape so that it does not leak reliably, and further, since it is filled with a waterproofing gel or the like, there is a problem that it is difficult to disassemble the case. is there. In the type that does not fill the entire circumference, it is necessary to further have a structure for waterproofing between the case and the cover. In this case, there is a problem that the internal pressure changes as in the former structure.

  In the control device as described in Patent Document 1, a waterproof structure with the cover is required because the problem of decomposability and the connection portion are not coated, and the structure is expensive. The structure described in Patent Document 2 also has a problem of decomposability, and a complicated structure is adopted to construct a structure that does not leak reliably, resulting in an expensive structure.

JP 2002-198471 A JP-A-8-125071

  An object of the present invention is to provide an inexpensive control device with a low manufacturing cost, in which a substrate and a connector can be easily taken out without impairing waterproofness and dustproofness, and a simplified housing case and cover can be adopted. Is.

  Only the inner part of the board and the connector is coated with a waterproofing adhesive on the entire circumference except for the part that needs to be taken around the whole area or to dissipate heat and ground. The case and cover to be accommodated can be simplified. With this structure, the above object can be achieved.

  ADVANTAGE OF THE INVENTION According to this invention, it can be set as the structure which can reduce the influence on the harness for control apparatuses, ensuring waterproofness, dustproof property, and rust prevention capability. In addition, since it is possible to use a case and a cover that are excellent in decomposability and are inexpensive, it is possible to provide a highly reliable and inexpensive control device.

  The cover of the connector connected to the board and the entire circumference of the part installed inside the case are coated with waterproof adhesive, and a waterproof structure is provided between the connector and the case that houses the board, and the cover It is not done. Moreover, the structure which seals the ventilation component or connector part currently provided in the prior art is not provided so that the pressure difference in a control apparatus may not affect a harness etc. The substrate coating is masked at portions that need to be connected to heat transfer and ground, and is not coated with a waterproof adhesive. These parts have a structure in contact with a heat transfer boss, a ground, and a fixing boss provided on the case side.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a sectional view showing the configuration of an embodiment of the present invention. A substrate 2 having a circuit composed of electronic components 1 and patterns for electrically controlling an engine (not shown) is connected by a connector 3 and solder 5 for electrical connection to the outside. The connector 3 and the board 2 are fixed to the case 4 having the heat radiation fins 41 by screws 6. A cover 7 is fixed to the case 4 with screws 6 so as to cover the substrate 2. The installation area 31 where the connector 3 is installed and the entire circumference of the substrate 2 are coated with a waterproofing adhesive 8 for waterproofing and dustproofing.

  A waterproof structure is not provided between the case 4 and the cover 7. For this reason, since a minute gap is generated on the contact surface, the ventilation filter 9 for preventing the internal / external pressure difference of the control device and the waterproof portion 32 of the connector 3 are not provided (illustrated by dotted lines). Since the connector 3 and the substrate 2 are configured as described above, the structure can be easily disassembled by removing the screw 6 from the case 4 and the cover 7.

  FIG. 2 is a cross-sectional view showing another embodiment of the present invention. The case 4 is provided with a grounding / fixing boss 43 between the heat transfer boss 42 and the substrate 2. The board 2 is provided with a heat transfer area 21 for transferring heat generated by the electronic component 1 to the case 4 and a fixed area 22 for securing the ground between the case 4 and the board 2. The installation area 31 of the connector 3 and the substrate 2 are coated with the waterproof adhesive 8 so that the heat area 21 and the fixed area 22 are exposed. The two heat transfer areas 21 and the fixed area 22 exposed when the connector 3 and the substrate 2 are assembled to the case 4 after coating with the waterproof adhesive 8 are configured to come into contact with the case 4.

  FIG. 3 is a cross-sectional view showing that the heat transfer component 10 is installed in advance in the heat transfer area 21 exposed in FIG. Before the heat transfer area 21 provided on the substrate 2 is coated with the waterproof adhesive 8, the heat transfer component 10 is installed in advance with the heat transfer adhesive 11 or the like, and then coated with the waterproof adhesive 8. Is.

  FIG. 4 is a cross-sectional view showing another embodiment of the present invention. The connector 3 is provided with a board connection terminal 33 for connecting to the board 2. By increasing the viscosity of the waterproof adhesive 8, the waterproof adhesive 8 is not impregnated to the inside of the board connecting terminal 33, so that the connector 3 is connected to the harness connecting terminal 34 (not shown). The waterproof adhesive 8 has a structure that can prevent penetration.

  FIG. 5 is a sectional view showing another embodiment of the present invention. Since the structure of the present invention does not provide a waterproof structure between the case 4 and the cover 7, it is assumed that water enters from the outside. Since the board 2 and the connector 3 are coated with the waterproof adhesive 8, the waterproof adhesive 8 and the case 4 and the cover 7 are not damaged at the time of intrusion. Since there is a possibility of accelerating the deterioration, drain holes 44 are provided in at least two directions so that the infiltrated water can escape to the outside.

Sectional drawing which shows the Example of this invention. Sectional drawing which shows the Example which a part of this invention has exposed. Sectional drawing which shows another Example shown in FIG. Sectional drawing which shows the Example comprised without making the connector terminal part of this invention impregnate. Sectional drawing which shows that the drain hole of this invention is installed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electronic component 2 Board | substrate 3 Connector 4 Case 5 Solder 6 Screw 7 Cover 8 Waterproof adhesive 9 Ventilation filter 10 Heat transfer component 11 Heat transfer adhesive 21 Heat transfer area 22 Fixing area 31 Installation area 32 Connector waterproof part 33 Board Connection terminal 34 Harness connection terminal 41 Fin 42 Heat transfer boss 43 Fixing boss 44 Drain hole

Claims (4)

An electronic circuit for control has a connector formed by a pattern formed on an electronic component and a substrate and a connector for connecting the substrate and an external device, and the substrate is provided with fins for heat dissipation and formed by aluminum die casting. It is assumed that the cover is fixed to the inner surface of the case, and is further fixed to the case with screws to cover the board, and is installed in an environment that requires waterproofness. in the control device, the substrate with waterproof adhesive inner portion of the substrate and the connector is intended for waterproofing, the entire circumference in a state of the connector only are Koti in g, further between the cover and the case incorporate them It is characterized in that no waterproof member is installed, no venting parts for the purpose of releasing the internal pressure of the control device, and no sealing structure for sealing the connector part is installed. Control device.   In order to conduct the heat generation of the electronic component mounted on the substrate, the portion that contacts the case and the portion that needs to be grounded by contacting the substrate and the case are exposed. A control device characterized by being coated with a waterproof adhesive. In those formed as claim 1, the viscosity of waterproof adhesives to be coated, high enough not impregnated into the connector inside the connection terminal side for connecting the said connector board, said connector A control device, wherein only the connection terminal surface layer on the non-opposing side is coated, and a cavity is provided between the connection terminal surface layer and the connector.   4. The control device according to claim 1, wherein the heat transfer component is previously installed on the substrate and coated with a waterproof adhesive so that the heat transfer component is exposed.

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