Keihin Corporation

Tatsuo Koike

Mitsuhiro Ito

Kazuya Nagasawa

Motoaki Somaki

Shigeharu Matsusaka

Masashi Hayasaka

A power drive unit is configured to comprise a heat sink, a power module pressed by a press member to the heat sink to be fastened thereto and a spring member that has a substantially circular shape and is installed between the power module and the press member. With this, the power module can be fastened to the heat sink without incurring layout limitation, degradation of heat release performance and the like. Also, since the power drive unit further includes a projection that protrudes from the press member to be engaged with an engagement hole bored at the center of the spring member, engagement of the projection of the press member with the engagement hole of the spring member functions to prevent displacement of the press member relative to the spring member, thereby making loads acting on the power modules uniform.

Power drive unit including a heat sink and a fastener

In a case for housing an electronic circuit board, the opening edge of the case body is formed with a prescribed distance below the board mounting surface. The board is fastened on the mount of the case body with the fastening means. The case body is then inverted and is placed over a rising coating bath, and then the coating bath is raised close to the opening edge such that the board is dipped in the coating liquid and is coated. By this, application of the coating liquid to prescribed regions constituting coating-prohibited regions of the case body can be prevented. Cost can therefore be kept down and complication of the processing steps prevented because no masking of the case body is necessary. Moreover, the reliability of the electronic circuit unit can be enhanced and the need for a jib is eliminated. This helps to avoid complication of the fabrication process and makes another contribution to cost control.

Electronic circuit board case and method of producing electronic circuit unit

A fastening member for an electronic circuit board having an elastically deformable leg formed in a case for housing the electronic circuit board and a projection formed continuous with the leg to be engaged with the electronic circuit board so as to fasten the electronic circuit board on a prescribed mounting surface in the case. In the member, the projection is engaged with the electronic circuit board such that a prescribed angle is formed between a surface of the projection contacting the electronic circuit board, when the electronic circuit board is fastened on the mounting surface in the case. With this, since the tangent between the board contact surface and the electronic circuit board is variable within the range of the board contact surface, molding error can be tolerated (absorbed) and volumetric variation produced by temperature change can be readily coped with.

Electronic circuit board fastening member

A case for housing an electronic circuit board having a case body formed with an opening and a sealing member for sealing the opening, wherein one of the case body and the sealing member is formed with one fastening member composed of an elastically deformable leg and a projection continuous therewith for enabling attachment of the sealing member to the case body by engagement of the fastening member with a prescribed region of the other. The projection is continuous with the leg and has a first surface formed to contact the prescribed region at a prescribe angle and a second surface continuous with the first surface and formed parallel to the prescribed region. With this, molding error can be tolerated and stress owing to volumetric variation produced by temperature change or to vibration can be readily coped with. Moreover, it is possible to prevent release of the engagement of the projection with the prescribed region, and thus to prevent separation of the sealing member from the case body.

Electronic circuit board case

An electronic control unit ( ) mounted in a vehicle engine compartment, having a plastic case body ( ), metal collars ( ) each molded into the plastic case body, a metal base ( ) having bolt through-holes ( ) prepared in the same number of the metal collars such that a bolt passes through each metal collar and one of the holes corresponding thereto, and a heat-generating component ( ) mounted on the base. The characteristic features are that an outer surface of each metal collars ( ) that comes in contact with the plastic case body ( ) is formed with projections and depressions, each metal collar ( ) is shaped to be protruded from the upper and lower ends of the plastic case body in the same direction as the bolt-through hole ( ), and the plastic case body ( ) and the metal base ( ) are joined together with adhesive ( ) in such a way that the metal collars and the metal base are fastened together with the bolts to be mounted in the engine compartment, thereby ensuring good mounting strength with superior watertightness.

Growing community of inventors

Kakuda, Japan

Tatsuo Koike