JPH11324706A - Control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control unit in which resin can be filled into the inside of a case by selectively making higher the height of a constituent element whose height is higher from a printed circuit board so that a resin filling amount to the inside of the case can be reduced even though the constituent element of a control circuit forming body is arranged in an optional position on the printed circuit board in the inside of the case. SOLUTION: In a control circuit forming body 5 in the inside of a case 6, surrounding bodies 9A, 9B are arranged to circumferences of constituent elements whose height are higher from a printed circuit board 2 out of respective constituent elements. Resin 8 is filled into the inside of the case 6 by changing its height in a way that it is made higher in the surrounding bodies 9A, 9B and made lower outside thereof, so that at least metallic parts of both the constituent elements surrounded by the surrounding bodies 9A, 9B and the other constituent elements can be filled up with the resin 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control unit in which a control circuit for controlling, for example, fuel injection of an internal combustion engine and an ignition device is provided on a printed circuit board.

[0002]

2. Description of the Related Art In general, a control unit of this type used for controlling an internal combustion engine in an outboard motor, a snowmobile, or the like includes a control circuit and a control circuit structure including a printed circuit board on which the control circuit is mounted. In order to improve the moisture resistance and water resistance of the electronic component, the electronic component including the connector is molded with a resin having low conductivity such as epoxy, urethane or silicon until the metal part of the electronic component including the connector is hidden. However, metals that are electrically insulated from others, such as a metal case of an electrolytic capacitor, are excluded.

FIG. 3 is a side view showing the structure of a conventional control unit of this type. The control unit includes a control circuit 1 for controlling fuel injection of an internal combustion engine, controlling an ignition device, and the like.
Terminals of electronic components 3 such as transistors, resistors, capacitors, etc. used in the above are electrically and mechanically connected to printed conductors of a printed circuit board 2 by soldering, and the control circuit 1 is connected to the outside by a connector 4. And a control circuit structure 5 having a structure as described below. Such a control circuit component 5 is disposed in the case 6 with the connector 4 penetrating through the cutout groove 7 of the peripheral wall 6 a of the case 6, and the highest inside the case 6 from the bottom 6 b of the case 6. The resin 8 is filled so as to embed a metal part 4a formed of a terminal part of the connector 4 which is a component of the control circuit component 5 existing at the position.

[0004]

However, in the control unit having the structure shown in FIG. 3, the bottom surface 6b of the case 6 is placed horizontally, and the terminal of the connector 4 which is the highest component from the printed circuit board 2 is located. Metal part 4a
Since the mold resin 8 is filled at the same height as a whole so as to bury the resin, there is a problem that the filling amount of the resin 8 is large, heavy, and the cost is high.

Therefore, as shown in FIG. 4, the resin 8 is higher on the side where the metal part 4a, which is the terminal part of the connector 4, which is the component located at the highest position from the printed circuit board 2 is embedded, and lower on the opposite side. It has been studied to fill the case 6 so that the resin surface becomes the inclined surface 8a.

According to such a structure, there is an advantage that the filling amount of the resin 8 into the case 6 can be reduced. However, in the case of this structure, it is necessary to fill the resin 8 with the case 6 in an inclined state when filling the resin 8 and to cure the case 8, which is troublesome. Further, since the electronic component 3 having a high height from the printed circuit board 2 cannot be arranged on the side where the filling height of the resin 8 is low, there is a problem that the mounting layout of the electronic component 3 becomes difficult.

An object of the present invention is to provide a control unit capable of reducing the amount of resin filled in a case.

Another object of the present invention is to reduce the amount of resin charged into the case even if the components of the control circuit structure are arranged at any positions on the printed circuit board in the case. Another object of the present invention is to provide a control unit capable of selectively increasing the height of a component having a height higher than a printed circuit board and filling the resin.

Another object of the present invention is to provide a control unit which can reduce the amount of resin to be filled by using a low cost and easily available enclosure.

[0010]

According to the present invention, an electronic component used in a control circuit is electrically and mechanically connected to a printed circuit board, and the control circuit is connected to the outside by a connector or a wire harness. A control unit comprising a control circuit component, wherein the control circuit component is disposed in a case, and the case is filled with resin so as to embed metal parts of respective components of the control circuit component, thereby improving the control unit. Things.

In the control unit according to the present invention, the control circuit component in the case is provided with an enclosure around the component having a higher height from the printed circuit board among the components. The resin is high inside the enclosure, low outside, at least at the height where the metal part is buried, and the components enclosed by the enclosure and other components are filled in the case with different heights I have.

According to the control unit having such a structure,
The amount of resin charged into the case can be reduced, so that the weight of the control unit can be reduced and the cost can be reduced.

In particular, according to the structure of the present invention, even if the components of the control circuit component are arranged at any positions on the printed circuit board in the case, the amount of resin filling in the case can be reduced. As described above, the components having a height from the printed board can be selectively increased in height to be filled with the resin, and there is an advantage that the layout of the electronic components is not restricted.

[0014] In this case, it is preferable to use a resin pipe as an enclosure integrally surrounding the components. According to such a resin pipe, a long resin pipe can be easily obtained at low cost by cutting it into a required length.

[0015]

1 (A) and 1 (B) show a first embodiment of a control unit according to the present invention. FIG. 1 (A) is a plan view of the control unit and FIG. 1 (B)
FIG. 4 is a partially cutaway side view of the control unit.

In the control unit of this example, an enclosure made of resin or the like is provided around the connector 4 which is the highest component from the printed circuit board 2 among the components of the control circuit component 5 in the case 6. 9A is provided. In the case of this example, the enclosure 9A has a U-shape, is disposed on the printed circuit board 2, and includes the connector housing 4b as a part of the enclosure 9A, and includes a terminal portion of the connector 4. It surrounds the metal part 4a. The enclosure 9A and the connector housing 4b are adhered with an adhesive so as to close a gap between them.

The resin 8 comprises a connector 4 which is a component surrounded by an enclosure 9A and an electronic component 3 which is another component.
In both cases, at least the height at which the metal parts 4a and 3a are buried is high in the enclosure 9A, low outside, and filled in the case 6 with a different height. If there is a gap between the enclosure 9A and the printed circuit board 2, once the resin 8 is filled in the case 6 to a height at which the metal part of another component having a low height from the printed circuit board 2 is filled. If the resin 8 is filled in the enclosure 9A after the resin is hardened by curing, the resin 8 filled in the enclosure 9A does not leak from the gap between the enclosure 9A and the printed circuit board 2.

The parts corresponding to FIG. 3 described above include:
The same reference numerals are given.

According to the control unit having such a structure,
The amount of the resin 8 filled in the case 6 can be reduced, so that the weight of the control unit can be reduced and the cost can be reduced.

FIG. 2 is a partially cutaway side view of a second embodiment of the control unit according to the present invention. In addition,
Parts corresponding to those in FIG. 1 are denoted by the same reference numerals.

In this control unit, the printed circuit board 2 of the components of the control circuit
Around the electronic component 3 such as the connector 4 and the transistor, which are the components having a high height from the surroundings, made of resin or the like.
A and 9B are provided. The enclosure 9A for the connector 4 is provided similarly to the first example. The enclosure 9B of the electronic component 3 such as a transistor is used by cutting a long resin pipe such as a vinyl pipe into a required length and fitting it so as to surround the electronic component 3 on the printed circuit board 2. Has been placed. In this case as well, the resin 8 has a height from the printed circuit board 2 and a component composed of the electronic component 3 such as the connector 4 and the transistor surrounded by the enclosures 9A and 9B, respectively. Enclosures 9A, 9 of at least the other components such as the low surface mount electronic component 3 are set at a height at which the metal parts 4a, 3a are buried.
B is high inside, low outside, and is filled in the case 6 with a different height.

According to such a configuration, the printed circuit board 2
The present invention can be easily applied even if there are a plurality of constituent elements having a high height from.

In particular, according to this structure, even if each component of the control circuit component 5 is arranged at an arbitrary position on the printed circuit board 2 in the case 6, the amount of the resin 8 filled in the case 6 can be reduced. The connector 4, which is the tallest component from the printed circuit board 2, can be selectively increased in height and filled with resin 8, so that the electronic component 3 can be reduced.
There is an advantage of not being restricted by the mounting layout of the above.

In each of the above examples, the control circuit structure 5 having a structure in which the control circuit 1 is connected to the outside by the connector 4 is shown. However, the control circuit 1 is directly connected to the outside by the wire harness without using the connector 4. The present invention can be similarly applied to the case of the control circuit structure 5 having a structure as described above. That is,
In this case, since the end of the wire harness in the case 6 is connected to the printed circuit board 2 by soldering and has a low height, it is not necessary to surround the end with the enclosure 9A or 9B. Enclosure 9 around high-constituting components
You can enclose it in B.

The control unit shown in the above example is used not only for controlling fuel injection of an internal combustion engine and controlling an ignition device, but also for harvesting with a combine unit of an agricultural machine, which is a control unit for an accessory device of another machine. The present invention can be similarly applied to a control unit for threshing crushed grain, a control unit for controlling a power shovel for digging a hole with a civil engineering (construction) work machine, or the like.

[0026]

In the control unit according to the present invention,
The control circuit component in the case is provided with an enclosure around the component having a higher height from the printed circuit board among the respective components, and the resin is the same as the component enclosed by the enclosure and the other components. At least to the height where the metal part is buried, it is high inside the enclosure, low outside, filling the case with a different height, so the amount of resin filling in the case can be reduced, Therefore, the weight of the control unit can be reduced, and the cost can be reduced.

In particular, according to the structure of the present invention, even if the components of the control circuit component are arranged at any positions on the printed circuit board in the case, the amount of resin to be filled in the case can be reduced. As described above, the components having a height from the printed board can be selectively increased in height to be filled with the resin, and there is an advantage that the layout of the electronic components is not restricted.

[Brief description of the drawings]

FIG. 1A is a plan view showing a first example of an embodiment of a control unit according to the present invention, and FIG. 1B is a partially cutaway side view of the control unit.

FIG. 2 is a partially broken side view of a second example of the embodiment of the control unit according to the present invention.

FIG. 3 is a side view showing a configuration of a conventional control unit.

FIG. 4 is a side view showing a configuration of a control unit which is being studied by the present applicant.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control circuit 2 Printed circuit board 3 Electronic component 3a Metal part 4 Connector 4a Metal part 5 Control circuit structure 6 Case 6a Peripheral wall 6b Bottom part 7 Notch groove 8 Resin 8a Inclined surface 9A, 9B Enclosure

Claims (2)

[Claims] An electronic component used in a control circuit is electrically and mechanically connected to a printed circuit board. The control circuit includes a control circuit component having a structure connected to the outside by a connector or a wire harness. A control unit in which the control circuit component is disposed in a case, and the case is filled with a resin so as to embed metal parts of respective components of the control circuit component in the case; In the circuit component, an enclosure is provided around a component that is higher in height from the printed circuit board among the components, and the resin is the component enclosed by the enclosure and the other components. A control unit characterized by being filled inside the case at a height at which the metal part is buried, which is high inside the enclosure and low outside, and at a different height. 2. The control unit according to claim 1, wherein a resin pipe is used as the enclosure that integrally surrounds the periphery of the component.