JPH0536244Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a sealed structure for a rotary-operable electric component such as a rotary variable resistor or a rotary switch.

[Background of the idea]

Rotating electrical components are known and used in a variety of fields. For example, vehicles are sometimes equipped with an electrical device called a throttle position sensor in order to set the optimum amount of fuel to be supplied depending on the speed of the vehicle and drive the vehicle in an optimum fuel efficiency state.

A known type of throttle position sensor has a slider attached to a rotating shaft that rotates in response to the amount of depression of the accelerator pedal, and a slider receiver is connected to it so that it rotates integrally with the rotating shaft. A substrate with a resistor and a current collector formed on its surface is disposed opposite the slider receiver, and the slider is brought into sliding contact with the resistor and the current collector, thereby extracting the amount of rotation of the rotating shaft caused by the accelerator pedal as a change in resistance value.

The position sensor configured in this way is usually installed inside the bonnet of a vehicle, and for this purpose, the above-mentioned board and slider are connected to fuel such as gasoline, cooling water, and the outside. It is necessary to protect it from dirt, dust, etc.
For this reason, each member forming the throttle position sensor is generally housed in a housing and assembled with one end of the rotating shaft protruding outside from the housing.

However, in order to assemble each component of the throttle position sensor, such as the slider receiver and the board, into the casing, an opening for assembly is provided on one side of the housing for each of these components in the casing. It is formed. and,
After assembling each component through this opening, it is necessary to seal it to keep the storage area air-liquid-tight, but for this purpose, conventionally the entire housing was covered with a protective cover. . However, if the protective cover is attached to the housing in this manner, the overall shape of the throttle position sensor becomes large and there are disadvantages such as making it difficult to install it inside the hood.

On the other hand, it is also possible to fill the above-mentioned assembly opening with thermosetting resin to maintain the interior of the housing air-liquid tight, but in this case, when heated to harden the resin, There is a problem in that the temperature rises in the housing section of the housing, and the internal pressure rises, causing pores to be generated in the resin that is in a fluid state before hardening, making it impossible to achieve an air-liquid tight structure.

[Purpose of invention]

The present invention has been made in view of the above points, and it is an object of the present invention to provide a sealed structure for electrical components that has a simple configuration and can reliably maintain the inside of the casing in a sealed state without increasing the overall size. The purpose is to

[Summary of the idea]

In order to achieve this purpose, the sealed structure of the electrical component according to the present invention is such that a stepped portion is formed on the inner wall surface of a casing whose one end surface is open, and a substrate on which a conductive pattern is formed is attached to the stepped portion. and a lid fixed to the open surface of the casing, and this lid is provided with a ventilation tube that communicates between the inside and outside of the casing, and furthermore, on the outside of the lid, there is a connection between the inner wall surface of the casing and the outer circumferential surface of the ventilation tube. It is characterized by filling the space between the vents with a thermosetting resin and filling the inside of the vent with a closing part.

[Example of idea]

1 and 2 show a first embodiment of the present invention, in which FIG. 1 is a sectional view of a main part of a throttle position sensor, and FIG. 2 is a plan view of a lid body.

In FIG. 1, a housing 1 constitutes a casing of a throttle position sensor, and the housing 1 is designed to be fixedly mounted, for example, in the hood of an automobile. A storage section 2 for storing each member constituting the rotary variable resistor is formed within this housing 1, and one side of this storage section 2 has openings for assembling each of the above-mentioned members. Section 3 has been established.

A mounting opening 4 is formed in the housing 1 on the opposite side of the opening 3, and a bearing bush 5 is inserted into the mounting opening 4. An operating shaft 6 is rotatably fitted into the bearing bush 5, and one end of the operating shaft 6 is located outside the housing 1 and is connected to an accelerator pedal (not shown). , can be rotated by an amount corresponding to the amount of depression of the accelerator pedal.
Further, the other end of the operating shaft 6 extends into the storage portion 2 and is attached so as to be able to rotate integrally with the slider receiver 7. Sliders 8a and 8b are attached to the surface of the slider receiver 7, and each slider 8a,
8b is brought into sliding contact with a resistor 10a and a current collector 10b formed on the surface of the substrate 9, which is disposed opposite to the slider receiver 7, respectively.

Next, reference numeral 11 denotes a lid for closing the opening 3 of the storage section 2, and the lid 11 is made of an insulating material such as synthetic resin. By fitting the lid 11 into the opening 3, the substrate 9 is positioned so as to come into contact with the stepped portion 1a provided on the inner wall surface of the housing 1, and is slid against this. The child receiver 7 has its respective sliders 8a and 8 by a wave washer 12.
b are urged in the direction of contacting the resistor 10a and the current collector 10b, respectively, so that the sliders 8a and 8b and the resistor 10a and the current collector 10b can slide in good condition. It is configured to touch. A vent cylinder 13 is provided on the outer surface of the lid body 11 in a protruding manner. It is formed so as to slightly protrude from the open end of the opening 3 in the body 1. On the other hand, as shown in FIG.
It communicates with an air flow path 16 formed inside the
Further, the other side end portion communicates with the storage portion 2 via the recessed portion 17 . A resin reservoir 18 is formed in the middle of the air passage 14, and the air passage 14 extends from the resin reservoir 18 to the passage portion 1 on the ventilation cylinder 13 side.
4a and a passage portion 14b on the side of the recess 17, and in this embodiment, the passage portion 14a and the passage portion 14b form an angle of 90°.

Further, in the recess 17 of the lid 11, an outlet 20 is provided for leading out the outlet terminals 19 connected to both ends of the resistor 10a and the current collector 10b, respectively. terminal 19
are connected to the signal line 21 on the outside of the lid 11, respectively.
Each signal line 21 is inserted into the insulation lead-out body 22.

Further, in the figure, reference numeral 23 denotes a thermosetting resin filling member such as epoxy resin, and the filling member 23 covers the outer surface of the lid 11 at a portion between the inner wall surface of the casing 1 and the outer peripheral surface of the vent pipe 13. This seals the space between the outer circumferential surface of the lid 11 and the inner wall surface of the housing 1 and the outlet 20, and protects the outlet terminal 19 and the signal line 21 connected thereto by burying it. are doing. Further, reference numeral 24 denotes a hot melt injection member made of molten thermoplastic resin injected into the vent pipe 13.
3 is sealed, and the housing part 2 is held in an air-liquid tight manner at the opening 3 of the housing 1 by the thermosetting resin filling member 23 and the hot melt injection member 24. There is.

Note that 25 in the figure is a sealing member that maintains air-liquid tightness between the bearing bush 5 and the rotating shaft 6.

This embodiment is constructed as described above, and when assembling this throttle position sensor, first the operating shaft 6 is inserted through the bearing bush 5 inserted into the mounting opening 4 of the housing 1. . On the other hand, the wave washer 12 is inserted into the storage part 2 from the opening 3 side of the housing 1, and the slider receiver 7 to which the sliders 8a and 8b are attached is brought into contact with the wave washer 12, and then the wave washer 12 is inserted into the operating shaft 6. After fitting, the substrate 9 is placed in the housing 3 with the substrate 9 in contact with the resistor 10a and the current collector 11b. Thereafter, the lid 11 is inserted into the opening 3, and the lid 11 is brought into contact with the substrate 9, and by pressing this, the substrate 9 is brought into contact with the stepped portion 1a. At this time,
Needless to say, the extraction terminal 19 is inserted through the extraction port 20. Furthermore, an insulation extraction body 22 is attached to the casing 1, and the signal line 2 inserted through the insulation extraction body 22 is
1 to the extraction terminal 19, each member is installed into the housing 1.

Next, on the outside of the lid 11 inside the opening 3,
A thermosetting resin filling member 23 is filled between the inner wall surface of the casing 1 and the outer circumferential surface of the vent pipe 13, and is thermosetted. Here, this filling member 2 is used for heat curing.
3, the air inside the storage section 2 expands, but since the storage section 2 is in communication with the outside via the air passage 14 and the ventilation pipe 13, this expanded air is smoothly and reliably transferred to the outside. As a result, the pressure inside the storage section 2 will not increase, and there is no risk of creating pores or the like in the thermosetting resin filling member 23. Since the vent tube 13 is provided to protrude outward from the open end of the opening 3, there is no possibility that the thermosetting resin may get mixed into the vent tube 13 and block it. do not have. As a result, the storage section 2 can be sealed leaving the ventilation tube 13, and the extraction terminal 19 and the signal line 2 can be sealed.
1 can be protected.

Furthermore, after the thermosetting resin filling member 23 has cooled, a hot melt injection member 24 is added into the ventilation tube 13.
is injected to close the ventilation cylinder 13 and maintain the inside of the storage portion 2 in a completely air-liquid tight state. Here, in order to more completely block the ventilation tube 13 with the hot melt injection member 24, it is desirable to inject a slightly larger amount of resin than the internal volume of the air flow path 16 in the ventilation tube 13. If the hot melt injection member 24 flows into the storage portion 2, it will adhere to the substrate 9, thereby impairing its function as a throttle position sensor. However, in this embodiment, since the resin reservoir 18 is provided in the middle of the air passage 14 leading to the ventilation cylinder 13, even if the injection amount of the hot melt injection member 24 is slightly increased, the resin reservoir 18 Flowing into 18,
There is no risk of it entering the storage section 2.

As mentioned above, the thermosetting resin filling member 23 and the hot melt injection member 24 can completely and reliably seal each component of the throttle position sensor, making each component inside the housing section 2 liquid-proof. It can be protected from dust and the throttle position sensor can be operated stably.
Although this throttle position sensor is intended to be used under high-temperature conditions such as inside the bonnet of a vehicle, most of the closing member for the opening 3 is made of thermosetting resin, so it is susceptible to thermal deterioration. In addition, the thermoplastic resin injected into the vent tube 13 is injected until the vent tube 13 becomes almost solid, and since the vent tube 13 is long in the axial direction, Even if it undergoes some thermal deterioration, its closing function is not lost, and the storage section 2 can be maintained in a sealed state for a long period of time. moreover,
When the ventilation tube 13 is made of a synthetic resin material, the compatibility between the vent tube 13 and the hot melt injection member 23 is good.
The airtightness is extremely good.

FIG. 3 relates to a second embodiment of the present invention, showing a cross-sectional view of main parts of a throttle position sensor;
Parts corresponding to the figures are given the same reference numerals.

The difference between this embodiment and the first embodiment is as follows:
It is a member that closes the ventilation cylinder 13 of the lid body 11. That is, in the first embodiment, the hot melt injection member 24 is injected into the vent pipe 13 after the thermosetting resin filling member 23 has been cooled, and the vent pipe 13 is closed. In the example,
After the thermosetting resin filling member 23 has cooled down, the rubber stopper 26 is inserted into the ventilation cylinder 13 to close the ventilation cylinder 13.
is obstructed. The rubber stopper 26 is formed into a substantially cylindrical shape, and a tapered surface whose diameter increases in the insertion direction is formed around the end surface on the insertion side. The maximum diameter of this tapered surface is set to be much larger than the inner diameter of the vent pipe 13, and the outer diameter of the rubber plug 26 in other parts is set to be slightly smaller than the inner diameter of the vent pipe 13.

Therefore, when the rubber plug 26 is inserted into the vent cylinder 13, the rubber plug 26 is smoothly inserted into the vent cylinder 13 along the tapered surface while the end portion of the tapered surface is elastically deformed. When the insertion is stopped, the end of the tapered surface elastically returns and the vent tube 13 is hermetically closed by the rubber stopper 26.

In each of the above-described embodiments, the insulation extraction body 22 holding the signal line 21 was configured to be extracted to the side of the casing 1. You may also do so. Further, the ventilation cylinder 13 is not limited to projecting in a direction perpendicular to the lid 11, but may be extended in a direction parallel to this.

Further, in each of the above-described embodiments, a case has been described in which a rotary operation type electrical component is applied to a throttle position sensor, but it goes without saying that the present invention can be applied to other electrical components.

[Effect of idea]

As explained in detail above, according to the present invention,
With a simple structure, the overall shape can be miniaturized, and an electrical component with a completely airtight structure can be provided without generating pores or the like in the thermosetting resin during the heating process.

[Brief explanation of the drawing]

1 and 2 relate to the first embodiment of the present invention, the first being a sectional view of the main part of the throttle position sensor, the second being a plan view of the lid body, and the third being a cross-sectional view of the main part of the throttle position sensor. FIG. 2 is a sectional view of a main part of a throttle position sensor according to a second embodiment. 1... Housing, 2... Storage section, 3... Opening, 6
...Operation shaft, 7...Slider receiver, 8a, 8b...
Slider, 9...Substrate, 10a...Resistor, 10b
... Current collector, 11 ... Lid body, 13 ... Ventilation cylinder, 1
4...Air passage, 18...Resin reservoir, 23...Thermosetting resin filling member, 24...Hot melt injection member (closure member), 26...Rubber stopper (closure member).

Claims (1)

[Scope of utility model registration request] a housing having an open end face and a mounting opening formed in a closed face opposite to the open face; and an operating shaft rotatably mounted within the housing with one end protruding from the mounting opening. a slider receiver that is attached to the other end of the operating shaft and rotates in conjunction with the operating shaft; and a slider receiver that is arranged close to and opposite to the slider receiver in the housing. In the electrical component, the electrical component includes a board on which a conductive pattern is formed on a plate surface facing the board, and a slider attached to the slider receiver so as to be in sliding contact with the conductive pattern on the board. A stepped portion is formed on the wall surface, the substrate is held between the stepped portion and a lid fixed to the open surface, a ventilation tube is provided in the lid that communicates the inside and outside of the casing, and the lid is A sealed structure for an electrical component, characterized in that a thermosetting resin is filled between the inner wall surface of the housing and the outer circumferential surface of the vent tube on the outside, and a closing member is filled inside the vent tube.