This application is based on Japanese Patent Application No. 2019-071257 filed on Apr. 3, 2019, the disclosure of which is incorporated herein by reference.
The present disclosure relates to a vehicle control apparatus.
Devices for controlling a vehicle have been integrated with an electromechanical system including a sensor, an actuator or an integrated system having both of the sensor and actuator. Therefore, the demand for miniaturization, heat resistance, sealability, resistance against vibration, or the like of a control device has been increasing. For example, a control device may be disposed in an oil-immersion environment for satisfying the demand.
The present disclosure describes a vehicle control apparatus for controlling a transmission for a vehicle.
The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:
A vehicle control device for controlling a vehicle may be disposed in an oil-immersion environment for satisfying a demand such as miniaturization, heat resistance, sealability, resistance against vibration, or the like.
However, circuit components in a control device may deteriorate as oil enters the control device. For example, disconnection due to oil corrosion or short circuit caused by foreign substances may happen. With regard to a waterproof measure taken for the control device, a casing of the control device may be sealed by a silicon sealing material. However, in a situation where such a sealing structure is placed in oil, the silicon sealing material may swell with oil. Therefore, the sealability may not be maintained.
In one or more embodiments of the present disclosure, a vehicle control apparatus has stable sealability even though the vehicle control apparatus is covered by oil.
According to an aspect of the present disclosure, a vehicle control apparatus is disposed inside a housing for accommodating a transmission at an atmosphere of lubricant oil. The vehicle control apparatus may be covered by the lubricant oil. The vehicle control apparatus includes a metal base, a resin case, a printed circuit board and an oil-tight seal member. The resin case is attached to the metal base to form an interior space. The printed circuit board has an electronic component mounted on the printed circuit board. The electronic component is included in a control circuit for the transmission. The printed circuit board is disposed in the interior space. The oil-tight seal member is disposed between the metal base and the resin case to surround the printed circuit board. The metal base and the oil-tight seal member are at a hydrogen bonding state, and the resin case and the oil-tight seal member are at a covalent bonding state.
The adhesion strength is enhanced as the metal base and the oil-tight seal member are at the hydrogen bonding state, and the resin case and the oil-tight seal member are at the covalent bonding state.
In one or more embodiments of the present disclosure, the metal base is made of aluminum and applied with anodizing treatment. Therefore, the interface between the metal base and oil-tight seal member may be set at an optimal state for the hydrogen bonding.
In one or more embodiments of the present disclosure, the resin case is applied with plasma treatment. Therefore, the interface between the resin case and the oil-tight seal member may be set at an optimal state for the covalent bonding.
In one or more embodiments of the present disclosure, the oil-tight seal member includes fluororubber. Therefore, the oil-tight seal member has a relatively high resistance to the oil for lubrication, and has flexibility.
In one or more embodiments of the present disclosure, a recess for accommodating the oil-tight seal member is disposed at one of the metal base and the resin case, and a protrusion is disposed at the other one of the metal base and the resin case for pressing a central portion of the oil-tight seal member accommodated in the recess. In a case where the resin case is attached to the metal base, the spacing formed between the recess and the tip of the protrusion extending in an extension direction has a larger width than the spacing formed between the recess and the protrusion in a direction perpendicular to the extension direction. Therefore, it is possible to reduce vibration in a vertical direction (or the extension direction) transmitted to the printed circuit board when the vehicle is travelling. Hence, the resistance against vibration may be enhanced.
In one or more embodiments, the resin case is integrated with a connector penetrating inside and outside the housing. The connector has a ventilation hole for communicating with the interior space between the resin case and the metal case and outside of the housing. A breathable filter is disposed at a location where the ventilation hole faces the outside of the housing.
Since the space formed between the metal case and the resin case communicates with outside through the ventilation hole provided at the connector, the inner pressure does not change when the temperature inside the housing changes. Therefore, it is possible to reduce stress applied to the structure. Additionally, since the breathable filter at a location where the ventilation hole faces the outside, it is possible to inhibit a situation in which foreign substances are mixed into the housing. Moreover, the ventilation hole is provided at the connector penetrating inside and outside the housing, it is possible to miniaturize the vehicle control apparatus.
As illustrated in
Automatic transmission fluid 50, which corresponds to oil for lubrication, is injected into the T/M case 1. The automatic transmission fluid 50 may also be referred to as ATF 50. In other words, the TCU 3 is disposed in the atmosphere of the ATF 50, and is covered by the ATF 50. The metal base 4 is made of, for example, aluminum applied with anodizing treatment (or alumite treatment). Although not shown, mechanism as a main body of the transmission is disposed inside the T/M case 1.
As illustrated in
A penetration connector 12 is integrated with the resin case 7. The penetration connector 12 extends upward as shown at the right side of
A load-side connector 16 is integrated with the resin case 7 as illustrated at the left side of
As illustrated in
A support member 24 is disposed at the metal base 4. The support member 24 faces upward and supports the heat radiation member 23. The heat radiation member 23 may also be referred to as heat radiation adhesive 23. When the resin case 7 is attached to the metal base 4, the lower surface of the printed circuit board 9 is in contact with the heat radiation adhesive 23, which mounts on the support member 24. With regard to the heat radiation adhesive 23, hardening treatment is processed after the assembly of the TCU 3. The heat generated by the printed circuit board 9 is conducted to the metal base 4 through the heat radiation adhesive 23 and the support member 24, and then the heat is radiated.
The following describes a flow of assembling the TCU 3. As illustrated in
By performing the process described above, the anodized metal base 4 and the oil-tight seal member 21 are at a hydrogen bonding state. The resin case 7 processed by the plasma cleaning treatment and the oil-tight seal member 21 are at a covalent bonding state. In other words, hydrogen bonding is formed between the metal base 4 and the oil-tight seal member 21, and covalent bonding is formed between the resin case 7 and the oil-tight seal member 21.
As illustrated in
According to the present embodiment, the TCU 3 is disposed under an environment where the interior of the T/M case 1 may be covered by the ATF 50. The TCU 3 includes the metal base 4 and the resin case 7. The resin case 7 is integrated with the connector 12, and is attached to the metal base 4. The connector 12 penetrates the T/M case 1. The electronic component 8, which is included in the control circuit for transmission, mounts on the printed circuit board 9. The printed circuit board 9 is disposed in the interior space formed between the metal base 4 and the resin case 7. The oil-tight seal member 21 is disposed between the metal base 4 and the resin case 7 to surround the periphery of the printed circuit board 9. The penetration connector 12 has a ventilation hole 25 communicating between the interior space of the T/M case 1 and the exterior part of the T/M case 1, and the breathable filter 26 is disposed at a location where the ventilation hole 25 faces outside.
Since the space formed between the metal base 4 and the resin case 7 has communication with outside through the ventilation hole 25, the interior pressure may not change as the temperature inside the T/M case 1 changes. Hence, it is possible to reduce stress applied to the structure. It may be possible to inhibit a situation in which foreign substances enter the T/M case 1 by disposing the breathable filter 26 at a location where the ventilation hole 25 faces outside.
Since the ventilation hole 25 is provided at the penetration connector 12, it may be possible to reduce the size of the TCU 3. Since the cover 27 is provided to cover at least a part of the breathable filter 26, it may be possible to avoid a situation where the breathable filter 26 is touched and damaged when an operator performs installation or the like.
The metal base 4 and the oil-tight seal member 21 are at a hydrogen bonding state, and the resin case 7 and the oil-tight seal member 21 are at a covalent bonding state. Therefore, the adhesive strength may be enhanced to prevent the ATF 50 from entering the interface between the metal base 4 and the oil-tight seal member 21 and the interface between the resin case 7 and the oil-tight seal member 21.
Since the metal base 4 is made of aluminum and applied with the anodizing treatment and the resin case 7 is applied with the plasma treatment, the interface formed between the metal base 4 and the oil-tight seal member 21 is set to an optimal state for hydrogen bonding and the interface formed between the resin case 7 and the oil-tight seal member 21 is set to an optimal state for covalent bonding. Since the oil-tight seal member 21 is made of fluororubber, a material having relatively high resistance to the ATF 50 and having flexibility may be used.
The groove 20 for accommodating the oil-tight seal member 21 is formed at the metal base 4. The protrusion 22 is formed at the resin case 7 to press the central portion of the oil-tight seal member 21. The shape of the groove 20 is set such that, when the resin case 7 is attached to the metal base 4, the spacing in an extension direction from the tip of the protrusion 22 has a longer width than the spacing in a direction perpendicular to the extension direction. Therefore, it is possible to reduce vibration in a vertical direction (or the extension direction) transmitted to the printed circuit board 9 in a situation that the vehicle is travelling. Hence, resistance against vibration may be enhanced.
According to the present disclosure, the plasma treatment (or the plasma cleaning treatment) is performed on the resin case 7 to vaporize dirt as carbon dioxide in order to eliminate the dirt on the resin case. Therefore, the dirt removal allows the resin case 7 to form stronger covalent bonding with the oil-tight seal member 21.
Hereinafter, the identical parts as those in the first embodiment are designated by the same reference numerals, and explanations thereof are omitted. Differences from the first embodiment are described. In the TCU 31 according to the second embodiment as illustrated in
The lever 33 has: a one end that is rotatably supported by a housing 34 of the female connector 32; and the other end that rotates in a range of, for example, 90 degrees between a depth direction and a downward direction as shown in
In the TCU 35 according to a third embodiment as illustrated in
According to the third embodiment, a part of the housing 37 of the female connector 36 is adopted as the cover of the breathable filter 26. Therefore, it is possible to reduce the number of components, as similar to the second embodiment.
In a TCU 38 according to a fourth embodiment as illustrated in
In a TCU 42 according to a fifth embodiment as illustrated in
A TCU 46 according to a sixth embodiment as illustrated in
A TCU 47 according to a seventh embodiment as illustrated in
The oil-tight seal member may not be limited to fluororubber. The configuration of an oil-tight structure may not be limited to the one illustrated in
Although the present disclosure has been described in accordance with the examples, it is understood that the disclosure is not limited to such examples or structures. The present disclosure encompasses various modifications and variations within the scope of equivalents. Furthermore, various combination and formation, and other combination and formation including one, more than one or less than one element may be made in the present disclosure.
It is noted that a flowchart or the processing of the flowchart in the present application includes sections (also referred to as steps), each of which is represented, for instance, as S1. Further, each section can be divided into several sub-sections while several sections can be combined into a single section. Furthermore, each of thus configured sections can be also referred to as a device, module, or means.
Number | Date | Country | Kind |
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2019-071257 | Apr 2019 | JP | national |