JP2019092283A - Electronic control unit - Google Patents

Abstract

To provide an electronic control unit capable of preventing occurrence of short circuit between terminals due to dew condensation water.SOLUTION: An electronic control unit 1 comprises: a circuit board 3 on which electronic components are implemented; a metal casing 2 in which an upper surface opening 21, a side surface opening 22, and a substrate housing section 20 for accommodating the circuit board 3 are formed; a metal lid member 5 for blocking the upper surface opening 21 of the casing 2; and a resin connector section 4 that is disposed at the side surface opening 22 of the casing 2 and has a plurality of terminals 40 connected with the circuit board 3. The casing 2, lid member 5, and connector section 4 are coupled to each other via a seal material 6. In the connector section 4, terminal holes 70 for disposing the terminals 40 are formed in parallel. Between adjoining terminal holes 70, grooves 71, 72 are provided along the terminal 40.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to an electronic control unit for controlling electrical components mounted on a vehicle such as a car.

  In recent years, with the progress of electronic control of vehicles such as automobiles, the number of electronic control units mounted is increasing. The electronic control unit is usually covered by a case, and a circuit board mounted with electronic components is accommodated in the case, and a connector unit including a terminal electrically connected to the circuit board is provided. There is. And an electronic control unit is connected to an electrical component via a connector part by a wire harness.

  Here, if water droplets adhere to the circuit board or the like accommodated in the electronic control unit, there is a possibility that a short circuit may occur in the circuit. Therefore, the electronic control unit has a waterproof structure, and is provided with a communicating portion (breathing hole) for communicating the inside and outside of the unit (see Patent Document 1).

Japanese Patent Laid-Open No. 2000-50460

  However, in the case of the electronic control unit of the sealed structure as described above, for example, when water is applied to the electronic control unit to cause quenching, there is a possibility that condensation may occur in the electronic control unit. Then, when dew condensation occurs, if dew condensation water adheres in the vicinity of the opening of the terminal hole where the distance between the terminals is the narrowest, there is a possibility that a short circuit may occur between the adjacent terminals. In particular, when the connector portion is directed downward, dew condensation water tends to be accumulated near the opening of the terminal hole, which increases the possibility of a short circuit between terminals.

  Then, this indication is made in order to solve an above-mentioned problem, and it aims at providing an electronic control unit which can prevent generating of a short between terminals by dew condensation water.

One mode of the present disclosure made to solve the above problems is
A circuit board on which electronic components are mounted, a metal casing having an upper surface opening, a side surface opening and a substrate accommodating portion for accommodating the circuit substrate, and a metal for closing the upper surface opening of the casing A cover member and a resin connector portion including a plurality of terminals disposed at the side opening of the casing and connected to the circuit board, wherein the casing, the cover member, and the connector portion respectively In the electronic control unit connected via the sealing material,
Terminal holes for arranging the terminals are formed in parallel in the connector portion,
A groove is provided along the terminal between the adjacent terminal holes.

  In this electronic control unit, since a groove is provided along the terminals between adjacent terminal holes, condensation water generated inside the unit adheres to the vicinity of the opening of the terminal hole where the distance between adjacent terminals is the narrowest. Even if it does, condensation water flows into the ditch. Therefore, even if dew condensation water adheres in the vicinity of the opening of the terminal hole, no condensation water is accumulated between the adjacent terminal holes, so that the occurrence of short circuit between terminals due to dew condensation water can be prevented.

In the above electronic control unit,
The grooves are provided in a pair on both sides of the terminal,
The distance between the adjacent terminal holes is larger than the diameter of the dew condensation droplets calculated based on the temperature and humidity before and after condensation occurs, and the size of the electronic control unit,
The distance between the pair of grooves is preferably smaller than the diameter of the dew condensation water droplets.

  With such a configuration, even if dew condensation water that may be generated inside the electronic control unit adheres to the vicinity of the opening of the terminal hole, some of the dew condensation water falls on the groove, so the dew condensation water is Can be drained to the Therefore, the occurrence of a short between terminals due to dew condensation can be reliably prevented.

Also, in the above electronic control unit,
It is more preferable that a connecting groove for connecting the pair of grooves provided on both surface sides of the terminal is formed between the adjacent terminal holes.

  With such a configuration, when the condensed water adheres to the vicinity of the opening of the terminal hole, the condensed water is reliably flowed to either of the pair of grooves provided between the terminal holes through the connection groove. be able to. Therefore, the occurrence of a short circuit between terminals due to condensation water can be prevented more reliably.

  According to the electronic control unit of the present disclosure, the occurrence of a short between terminals due to dew condensation water can be prevented.

It is a perspective view of an electronic control unit concerning an embodiment. It is an exploded perspective view of an electronic control unit concerning an embodiment. It is a perspective view of a connector part. It is the figure which expanded the part of the adjacent terminal hole in a connector part.

  An electronic control unit according to an embodiment of the present disclosure will be described in detail with reference to FIGS. 1 to 4. In the present embodiment, a fuel pump controller (FPC) that controls a fuel pump will be described as an example of the electronic control unit.

<Overall Configuration of Electronic Control Unit>
As shown in FIGS. 1 and 2, the electronic control unit 1 according to the present embodiment includes a casing 2, a circuit board 3, a connector portion 4, a lid member 5, and a seal member 6. Then, the circuit board 3 is accommodated in the casing 2, and the connector portion 4 including the two connectors 4 a is sandwiched between the casing 2 and the lid member 5, and each is coupled via the sealing material 6 to the casing 2 The lid member 5 is fixed. In addition, the sealing material 6 is a thing apply | coated and hardened the liquid thing at the time of unit assembly.

  Such an electronic control unit 1 is attached, for example, in a state where the bottom of the casing 2 is in contact with the vehicle (body) so that the connector portion 4 does not face the sky direction, and is not shown by a wire harness It is electrically connected to a fuel pump (not shown) via the connector portion 4. In the present embodiment, the connector portion 4 is attached to the vehicle so as to be located downward.

<Configuration of casing>
The casing 2 is a substantially rectangular parallelepiped housing member made of metal (in this embodiment, for example, aluminum), and includes a substrate housing portion 20, an upper surface opening 21 and a side surface opening 22. The substrate accommodation portion 20 is a space for accommodating the circuit board 3 inside the casing 2. The upper surface opening 21 is opened on the entire upper surface of the casing 2, and a seal material groove 21 a in which the seal material 6 is disposed (applied) is provided at the edge thereof. The sealing material groove 21 a is formed on the entire periphery of the edge excluding the side opening 22. The upper surface opening 21 is closed by the lid member 5 via the sealing material 6. Thereby, the sealability in the junction part of casing 2 and lid member 5 is secured.

  The side opening 22 is opened on one side surface (one of four side surfaces) of the casing 2 with a part of the side wall 2 a remaining. A seal material groove 22 a in which the seal material 6 is disposed is formed inside the side opening 22. Both ends of the seal material groove 22a are connected to the seal material groove 21a. The connector portion 4 is disposed in the side opening 22 via the sealing material 6, and the side opening 22 is closed. In addition, a radiation fin 23 is formed on the outer surface of the bottom of the casing 2. Thus, the casing 2 also functions as a heat sink for radiating the heat generated from the electronic components mounted on the circuit board 3 to the outside of the casing 2.

<Configuration of circuit board>
The circuit board 3 is mounted with electronic components for controlling a fuel pump connected to the electronic control unit 1 and constitutes a control circuit. Although not shown, electronic components such as a microcomputer, a transistor, a coil, and a capacitor are mounted on the circuit board 3. Such a circuit board 3 is accommodated in the board accommodation portion 20 of the casing 2.

<Configuration of connector section>
The connector unit 4 includes two connectors 4 a and a plurality of terminals 40 electrically connected to the circuit board 3. The connector portion 4 is a resin molded product (in the present embodiment, for example, made of PBT resin), and a breathing hole 60 communicating the inside and the outside of the unit is integrally formed between the two connectors 4a (approximately central position). . The pressure inside the electronic control unit 1 is maintained at the same level as the atmospheric pressure by the breathing hole 60. Further, at the inlet of the breathing hole 60, a protrusion 61 projecting to the outside is formed. The protrusion 61 is also integrally molded with the connector portion 4.

  Further, as shown in FIG. 3, terminal holes 70 for arranging a plurality of terminals 40 are formed in parallel in the connector portion 4. The terminal 40 is omitted in FIG. The terminal hole 70 is a rectangular hole passing through the connector portion 4. The terminal hole 70 is formed slightly smaller than the terminal 40, and the terminal 40 is press-fit in the terminal hole 70 and disposed. Therefore, the entry of foreign matter from the terminal hole 70 can be prevented. Also, the opening 70 a of the terminal hole 70 is tapered and facilitates the press-fitting operation of the terminal 40 into the terminal hole 70.

  The terminal 40 to be pressed into the terminal hole 70 is straight before bending. Then, after the terminal 40 is press-fitted into the terminal hole 70, the terminal 40 is bent into a predetermined shape (in the present embodiment, a crank shape). Therefore, since the direction of the connector 4a with respect to the circuit board 3 is not limited, the degree of freedom in mounting is increased, and the commercial property is improved.

  Further, grooves 71 and 72 are provided along the terminal 40 between the adjacent terminal holes 70. That is, one pair of grooves 71 and 72 are formed facing each other on both surface sides (upper and lower sides in FIGS. 3 and 4) of the terminal 40. Thereby, since lightening of the connector part 4 is performed, generation | occurrence | production of a void can be suppressed at the time of resin molding. The pair of grooves 71 and 72 are connected by a connection groove 73. The connection groove 73 is formed on the same plane as the opening surface of the terminal hole 70 between the adjacent terminal holes 70.

  Here, the distance A between the adjacent terminal holes 70 is larger than the diameter D of the dew condensation water droplets calculated based on the temperature and humidity before and after dew condensation occurs (before and after rapid cooling) and the size of the electronic control unit 1. , 72 are set to be smaller than the diameter D of the dew condensation water drop (B <D <A). As an example of this, set values in the present embodiment will be described.

In the present embodiment, the above set value is determined on the assumption that the electronic control unit 1 is rapidly cooled from the operation and dew condensation occurs. First, the internal temperature during operation (before quenching) of the electronic control unit 1 is 80 [° C.], the relative humidity is 80 [% RH], the temperature after quenching is 0 [° C.], and the relative humidity is 100 [% RH] And The internal volume of the electronic control unit 1 is 40 cm ³ , the surface area of the casing 2 is 8000 mm ² , and the surface area of the lid member 5 is 2000 mm ² .

Then, based on the temperature, relative humidity, and saturated water vapor pressure, the amount of water vapor during the operation of the electronic control unit 1 (before quenching) is 233 g / m ³ , and the amount of water vapor after quenching is 4.85 g / m 3 ³ ] is calculated. Therefore, the amount of condensation after rapid cooling is 228.1 [g / m ³ ].

Here, since the internal air of the electronic control unit 1 due to the temperature change before and after the quenching is reduced from 40 cm ³ to 31 cm ³ (volume ratio 0.77), the amount of condensation inside the electronic control unit 1 Becomes 0.007 [g].

And since the casing 2 side is provided with the radiation fin 23 and is in contact with the body of the vehicle, the temperature does not become high even during the operation of the electronic control unit 1, so it is considered that dew condensation occurs on the lid member 5 side. Therefore, the volume of dew condensation water in the lid member 5 is 0.0014 cm ³ because the surface area ratio is 0.2. Accordingly, the diameter D of the dew condensation droplet is D = 1.4 [mm].

  Therefore, in the present embodiment, in order to satisfy the above relationship (B <D <A), the interval A between adjacent terminal holes 70 is A = 1.5 [mm], and the interval B between the grooves 71 and 72 is It is assumed that B = 1.2 [mm].

  By setting the intervals A and B in this manner, when the dew condensation water droplets generated inside the electronic control unit 1 adhere to the vicinity of the opening 70 a of the terminal hole 70, a part of the dew condensation water droplets is the groove 71 or As it falls on the groove 72, dew condensation droplets can be made to flow reliably to the groove 71 or the groove 72.

  Note that the intervals A and B and the diameter D of the dew condensation droplets illustrated here are an example, and the condensation amount varies depending on the size of the electronic control unit and the like, and thus the diameter D of the condensation droplets varies. The intervals A and B which are optimum for each specification may be set.

  The connector portion 4 includes an inner wall portion 41 disposed inside the side opening 22 of the casing 2 and an outer wall portion 42 disposed outside the side opening 22 and contacting the outer surface of the casing 2. There is. The heights of the inner wall 41 and the outer wall 42 are substantially the same. The tip of the inner wall 41 is fitted in the sealing material groove 22a. That is, the tip of the inner wall 41 is embedded in the sealing material 6. Thereby, the sealing property in the junction part of the connector part 4 and the casing 2 (side surface opening part 22) is ensured.

  Furthermore, in the connector portion 4, a substrate holding portion 44 extending to the inside of the casing 2 is formed at both ends thereof. The circuit board 3 accommodated in the substrate accommodation portion 20 of the casing 2 is fixed at a predetermined position by the substrate holding portion 44 and the fixing screw 46.

  The connector 4 disposed in the side opening 22 of the casing 2 is attached to the casing 2 by the lid 5 so that the connector 2 is interposed between the casing 2 and the lid 5 via the sealing member 6. It is coupled to the casing 2 and the lid member 5. A seal material groove 45 in which the seal material 6 is disposed (applied) is formed in the connector portion 4 at the joint portion between the connector portion 4 and the lid member 5. The convex part 5a is fitted. Thereby, the sealing property in the connection part of the connector part 4 and the cover member 5 is ensured.

<Structure of lid member>
The lid member 5 closes the top opening 21 of the casing 2 in a state where the connector portion 4 is disposed in the side opening 22 as shown in FIGS. 1 and 2. The lid member 5 is formed with a flat portion 53 located at the edge and a projecting portion 51 protruding from the flat portion 53. And the convex part fitted in the sealing material groove | channel 45 of the connector part 4 is formed in the plane part 53. As shown in FIG.

<Function to prevent short between terminals in electronic control unit>
Next, the case where dew condensation occurs in the electronic control unit 1 having the above configuration will be described. For example, when the electronic control unit 1 is operated and water is applied and quenched, condensation occurs. Then, when condensation occurs, in the electronic control unit 1, since the connector portion 4 is positioned downward, condensed water flows to the connector portion 4 and adheres to straddle the adjacent terminals 40 and 40, thereby causing a short between the terminals May occur.

  Therefore, in the electronic control unit 1, a pair of grooves 71 and 72 facing each other on both sides along the terminal 40 is provided between the adjacent terminal holes 70. Therefore, even if dew condensation water generated inside the electronic control unit 1 adheres to the vicinity of the opening 70 a of the terminal hole 70 where the distance between the adjacent terminals 40 is the narrowest, the dew condensation water flows into the grooves 71 and 72. Therefore, even if dew condensation water adheres to the vicinity of the opening 70a of the terminal hole 70, no condensation water is accumulated between the adjacent terminal holes 70, so that occurrence of a short between terminals due to dew condensation water can be prevented. .

Then, in the electronic control unit 1, with respect to the size (diameter D) of the condensation water droplets that may be generated,
The intervals A and B are set so that the relationship of B <D <A is satisfied between the interval A of the adjacent terminal holes 70 (interval between the openings 70a) A and the interval B between the grooves 71 and 72. ing. Therefore, when the dew condensation water droplets generated inside the electronic control unit 1 adhere to the vicinity of the opening 70 a of the terminal hole 70, a part of the dew condensation water droplets fall on the grooves 71 or 72 and the dew condensation water droplets are Or, it flows reliably to the groove 72. Therefore, the occurrence of a short between terminals due to dew condensation can be reliably prevented.

  Further, in the electronic control unit 1, connection grooves 73 connecting the pair of grooves 71 and 72 provided on both sides of the terminal 40 are provided between the adjacent terminal holes 70. Therefore, when the condensed water adheres to the vicinity of the opening 70 a of the terminal hole 70, the condensed water reliably flows to either of the pair of grooves 71 and 72 through the connection groove 73. Therefore, the occurrence of a short circuit between terminals due to condensation water can be prevented more reliably.

  Even when a water droplet intrudes into the unit through the breathing hole 60, when the water droplet invading adheres to the vicinity of the opening 70a of the terminal hole 70, the water droplet flows to the grooves 71 and 72 directly or through the connection groove 73. It will flow. Therefore, even when water droplets intrude into the unit through the breathing hole 60, the occurrence of a short circuit between terminals can be reliably prevented.

  As described above, when condensation occurs, the electronic control unit 1 can prevent the occurrence of a short between terminals due to condensation water. Further, even when water droplets intrude into the unit through the breathing hole 60, it is possible to prevent the occurrence of a short circuit between terminals due to the intrusion water, as in the case of the condensation water.

  The embodiment described above is merely an example, and does not limit the present disclosure in any way, and it goes without saying that various improvements and modifications can be made without departing from the scope of the invention. For example, although the above-mentioned embodiment illustrated the fuel pump controller (FPC) which controls a fuel pump, this indication is applicable also to the controller which controls other electric components.

DESCRIPTION OF SYMBOLS 1 electronic control unit 2 casing 3 circuit board 4 connector part 40 terminal 70 terminal hole 71 groove 72 groove 73 connection groove

Claims (3)

A circuit board on which electronic components are mounted, a metal casing having an upper surface opening, a side surface opening and a substrate accommodating portion for accommodating the circuit substrate, and a metal for closing the upper surface opening of the casing A cover member and a resin connector portion including a plurality of terminals disposed at the side opening of the casing and connected to the circuit board, wherein the casing, the cover member, and the connector portion respectively In the electronic control unit connected via the sealing material,
Terminal holes for arranging the terminals are formed in parallel in the connector portion,
An electronic control unit characterized in that a groove is provided along the terminal between the adjacent terminal holes. In the electronic control unit according to claim 1,
The grooves are provided in a pair on both sides of the terminal,
The distance between the adjacent terminal holes is larger than the diameter of the dew condensation droplets calculated based on the temperature and humidity before and after condensation occurs, and the size of the electronic control unit,
An electronic control unit characterized in that a distance between the pair of grooves is smaller than a diameter of the dew condensation water droplet. In the electronic control unit according to claim 1 or 2,
An electronic control unit characterized in that a connecting groove for connecting the pair of grooves provided on both sides of the terminal is formed between the adjacent terminal holes.

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