JP6907776B2 - Electronic device - Google Patents

Description

The disclosure herein relates to waterproof electronic devices.

As disclosed in Patent Document 1, a waterproof electronic device is known. This electronic device includes a waterproof housing that is watertightly sealed by a sealing member, and a circuit board is housed in the internal space of the waterproof housing. A plurality of heat radiating fins are provided on the wall of the waterproof housing in order to dissipate the heat generated by the circuit board. In addition, a ventilation hole is provided in the wall of the waterproof housing, and a breathing filter is attached so as to close the ventilation hole.

Japanese Unexamined Patent Publication No. 2014-57001

With the miniaturization of electronic devices, it has become difficult to ensure heat dissipation.

In addition, depending on the arrangement of the electronic device, water rolled up when the vehicle is running, water used for car washing, a solution of calcium chloride used as a snow melting agent due to snow melting, etc. collects around the breathing filter, and the ventilation film of the breathing filter There is a risk of being flooded. When the ventilation film is exposed to water, for example, the ventilation between the internal space and the external space of the waterproof housing is blocked.

The present disclosure has been made in view of such a problem, and provides an electronic device capable of reducing the size of a vehicle body while suppressing imposition of mounting restrictions on the vehicle side and suppressing water exposure of a ventilation membrane. With the goal.

The present disclosure employs the following technical means to achieve the above objectives. The reference numerals in parentheses indicate the correspondence with the specific means described in the embodiment described later as one embodiment, and do not limit the technical scope.

One of the disclosures is an electronic device mounted on a vehicle.
A waterproof housing (20) having a wall portion (210) formed with a through hole (211), and a waterproof housing (20).
The circuit board (30) housed in the internal space of the waterproof housing and
A fan (41) including a blade (411) and a member for rotatably accommodating the fan, which is arranged on the wall portion so as to cover the through hole while facing the peripheral portion of the through hole on the outer surface of the wall portion and penetrates. A housing (42) that is watertightly sealed between the wall and the entire circumference around the hole, and a base portion (422d) that is an inner part of the watertightly sealed portion of the housing, projecting into the internal space and forming a circuit board. An electrically connected terminal (43) and a plurality of vents (420,421) provided in the housing so that an air flow along the outer surface of the wall is formed as the fan rotates. Blower unit (40) with
A breathing filter that is placed in the housing and blocks the flow of liquid between the external space and the internal space while allowing the flow of gas between the external space and the internal space, which is the space outside the waterproof housing. 60) and
With
The waterproof housing communicates the external space and the internal space at the wall portion, and is the region outside the watertight sealing portion of the projected region of the blower unit in the plate thickness direction of the circuit board, and is used for the rotation of the fan. It has a vent (212) formed on the path of the accompanying air flow,
The breathing filter includes a ventilation membrane (61) arranged on the outer surface side of the wall so as to close the ventilation holes.

In this electronic device, the air blower unit can forcibly create an air flow to cool the waterproof housing. The blower unit has better heat dissipation than the heat dissipation fins. Therefore, it is possible to reduce the size of the electronic device as compared with the case where the heat dissipation fins are provided in order to secure the heat dissipation equivalent to that of the blower unit.

Further, a through hole is provided in the wall portion of the waterproof housing to attach the blower unit, and the blower unit and the circuit board are connected via a terminal protruding from the base portion of the housing into the internal space. For this reason, it is necessary to connect the circuit board and the blower unit via a wire harness or the like provided outside the waterproof housing, or electrically connect another device provided in the vehicle to the blower unit. There is no. Therefore, it is possible to suppress imposing mounting restrictions on the vehicle side.

In addition, a ventilation hole for a breathing filter is provided in the projection area of the blower unit in the waterproof housing (wall portion). Therefore, the blower unit can prevent the water rolled up by the vehicle during traveling, the water used for washing the vehicle, and the like from hitting the breathing filter. Further, ventilation holes and thus a breathing filter are provided on the path of the air flow accompanying the rotation of the fan. Therefore, even if water stays around the breathing filter, it can be kept away from the breathing filter by the air flow. As described above, it is possible to suppress the water exposure of the ventilation membrane.

The other one of the present disclosure is an electronic device mounted on a vehicle.
A waterproof housing (20) having a wall portion (210) formed with a through hole (211), and a waterproof housing (20).
The circuit board (30) housed in the internal space of the waterproof housing and
A fan (41) including a blade (411) and a member for rotatably accommodating the fan, which is arranged on the wall portion so as to cover the through hole while facing the peripheral portion of the through hole on the outer surface of the wall portion and penetrates. A housing (42) that is watertightly sealed between the wall and the entire circumference around the hole, and a base portion (422d) that is an inner part of the watertightly sealed portion of the housing, projecting into the internal space and forming a circuit board. An electrically connected terminal (43) and a plurality of vents (420,421) provided in the housing so that an air flow along the outer surface of the wall is formed as the fan rotates. Blower unit (40) with
A breathing filter that is placed in the housing and blocks the flow of liquid between the external space and the internal space while allowing the flow of gas between the external space and the internal space, which is the space outside the waterproof housing. 60) and
The waterproof housing communicates the external space and the internal space at the wall portion, and has a ventilation hole formed in the region outside the watertight sealing portion of the projected region of the blower unit in the plate thickness direction of the circuit board. Has (212)
The breathing filter includes a ventilation membrane (61) arranged on the outer surface side of the wall so as to close the ventilation holes.
The fan has a protrusion (412) that projects toward the breathing filter and rotates integrally with the blades.

With this electronic device as well, as with the other electronic devices described above, the air flow can be forcibly created by the blower unit to cool the waterproof housing. Therefore, the physique of the electronic device can be reduced. In addition, the blower unit and the circuit board are connected via terminals. Therefore, it is possible to suppress imposing mounting restrictions on the vehicle side.

In addition, the blower unit can prevent the water or the like that the vehicle has swirled up while traveling from hitting the breathing filter. Even if water stays around the breathing filter, the protrusion rotates with the rotation of the fan, and the water on the breathing filter can be repelled. As described above, it is possible to suppress the water exposure of the ventilation membrane.

It is a perspective view of the electronic device which concerns on 1st Embodiment. It is sectional drawing which follows the line II-II of FIG. It is a top view of the blower unit seen from the bottom wall side. It is sectional drawing which shows the modification, and corresponds to FIG. It is sectional drawing which shows the periphery of the blower unit in the electronic device which concerns on 2nd Embodiment, and corresponds to FIG. It is sectional drawing which follows the VI-VI line of FIG. It is a top view of the blower unit seen from the bottom wall side. It is sectional drawing which shows the periphery of the blower unit in the electronic device which concerns on 3rd Embodiment, and corresponds to FIG. It is sectional drawing which follows the IX-IX line of FIG. It is a top view of the blower unit seen from the bottom wall side. It is sectional drawing which shows the periphery of the blower unit in the electronic device which concerns on 4th Embodiment, and corresponds to FIG.

A plurality of embodiments will be described with reference to the drawings. In a plurality of embodiments, the functionally and / or structurally corresponding parts are assigned the same reference numerals. In the following, the thickness direction of the circuit board is referred to as the Z direction. Further, one direction orthogonal to the Z direction, the longitudinal direction of the connector is indicated by the Y direction, and the direction orthogonal to both the Z direction and the Y direction is indicated by the X direction. Unless otherwise specified, the shape along the XY plane is the plane shape.

(First Embodiment)
First, a schematic configuration of the electronic device according to the present embodiment will be described with reference to FIGS. 1 to 3. In FIG. 2, the flow of air accompanying the rotation of the fan is indicated by a long-dotted arrow. In FIG. 3, the seal member and the respiratory filter are shown by broken lines for comparison of positions.

As shown in FIGS. 1 and 2, the electronic device 10 includes a waterproof housing 20, a circuit board 30, a blower unit 40, a seal member 50, and a breathing filter 60. The electronic device 10 is mounted on the vehicle. The electronic device 10 is arranged in an environment where the water rolled up by the vehicle during traveling, the water used for washing the vehicle, or the like can hit, for example, the engine room. The electronic device 10 of the present embodiment is configured as an electronic control unit (ECU) that controls an engine of a vehicle.

The waterproof housing 20 accommodates the circuit board 30 and protects the circuit board 30. The waterproof housing 20 is divided into two members in the Z direction, which is the thickness direction of the circuit board 30. The waterproof housing 20 has a case 21 and a cover 22. The waterproof housing 20 is configured by assembling the case 21 and the cover 22 to each other via a seal member (not shown).

The case 21 has a box shape with one side open. In this embodiment, the case 21 is formed of a metal material for heat dissipation. Specifically, the case 21 is molded by aluminum die casting.

The bottom wall 210 of the case 21 has a substantially rectangular shape in a plane. The bottom wall 210 of the case 21 corresponds to the wall portion of the waterproof housing 20. One of the four side walls connected to the bottom wall 210 is provided with a notch (not shown). This notch leads to an opening on one side of the case 21.

A through hole 211 is formed in the bottom wall 210. The through hole 211 is an opening for attaching the blower unit 40 to the case 21 of the waterproof housing 20. The through hole 211 is formed over the outer surface 21a and the inner surface 21b of the case 21.

In the present embodiment, the case 21 has a first accommodating portion 213 and a second accommodating portion 214 provided recessed with respect to other portions of the bottom wall 210 as a part of the bottom wall 210. The first accommodating portion 213 is provided on one end side in the X direction so as to accommodate the connector 33. The second accommodating portion 214 is provided to accommodate tall components such as aluminum electrolytic capacitors among the electronic components 32 constituting the circuit board 30. The second accommodating portion 214 is extended in the X direction, and one end thereof is connected to the first accommodating portion 213. The through hole 211 is formed in the bottom wall 210 except for the first accommodating portion 213 and the second accommodating portion 214. The through hole 211 is formed in a substantially flat portion of the bottom wall 210.

Reference numeral 215 shown in FIG. 1 is an attachment portion for attaching the electronic device 10 to the vehicle, and reference numeral 216 is a fixing hole for fixing the case 21 and the cover 22. A screw (not shown) is inserted into the fixing hole 216. The mounting portion 215 and the fixing hole 216 are provided integrally with the case 21.

Further, a vent hole 212 is formed in the bottom wall 210 of the case 21. Details of the ventilation holes 212 will be described later.

The cover 22, together with the case 21, forms an internal space 20s for accommodating the circuit board 30. By assembling the case 21 and the cover 22, the cover 22 closes the opening on one surface of the case 21. Further, the cover 22 closes the opening on one surface of the case 21, so that the notch formed in the side wall is partitioned, resulting in an opening (not shown). A part of the connector 33 is exposed to the outside by this opening.

In the present embodiment, the cover 22 is also formed by using a metal material in order to improve heat dissipation. The cover 22 is also molded by aluminum die casting. The cover 22 has a shallow box shape with an opening on one side. The cover 22 has a plurality of heat radiation fins 220 on the outer surface side.

The sealing member (not shown) of the waterproof housing 20 has an internal space 20s of a waterproof housing via the case 21 and the cover 22, the case 21 and the connector 33, and the cover 22 and the connector 33. It is provided so as to block communication with the space outside the body 20. This sealing member is arranged on the peripheral edge of the case 21 and the cover 22 so as to surround the internal space 20s. The peripheral portions of the case 21 and the cover 22 are watertightly sealed by the sealing member. As the sealing member, for example, a liquid adhesive before curing can be adopted.

The circuit board 30 is fixed to the case 21. The circuit board 30 has a printed circuit board 31 and an electronic component 32 mounted on the printed circuit board 31. The printed circuit board 31 is formed by arranging wiring on a base material formed of an electrically insulating material such as resin. A circuit is formed by the wiring and the electronic component 32. The printed circuit board 31 has a substantially rectangular shape in a plane.

The electronic component 32 is mounted on at least one of one surface 31a, which is the surface on the case 21 side, and the back surface 31b, which is the surface on the cover 22 side, of the printed circuit board 31. In the present embodiment, among the electronic components 32, a heat generating element 32a such as a power MOSFET is arranged on the one side 31a side. The heat generating element 32a is thermally connected to the bottom wall 210 of the case 21 via, for example, a heat radiating gel. An atmospheric pressure sensor 32b is also mounted on the printed circuit board 31 as an electronic component 32. The circuit board 30 executes a predetermined process by using the air pressure information in the external space detected by the atmospheric pressure sensor 32b, that is, the atmospheric pressure information.

A connector 33 is mounted on the circuit board 30. The connector 33 is mounted on one end side of the circuit board 30 in the X direction. A part of the connector 33 is exposed to the outside through the above-mentioned opening of the waterproof housing 20, and the remaining part is housed in the internal space 20s. Although not shown, the connector 33 has a housing formed of a resin material and a plurality of terminals formed of a conductive material and held in the housing. The above-mentioned sealing member is interposed between the case 21 and the housing and between the cover 22 and the housing.

The blower unit 40 is attached to the bottom wall 210 of the case 21. The blower unit 40 is attached to the through hole 211 of the case 21. The blower unit 40 forms a flow of air by rotation, thereby cooling the case 21, and thus the circuit board 30. The blower unit 40 includes a fan 41, a housing 42, terminals 43, and a fan board 44. The structure of the fan 41 is the same as that of a well-known axial fan. Therefore, in each figure, the fan 41 is shown in a simplified manner.

The fan 41 has a shaft portion 410 and a plurality of blades 411. The shaft portion 410 includes a rotating shaft 410a. The blade 411 rotates integrally with the rotating shaft 410a. Therefore, the rotating shaft 410a serves as the rotating shaft of the fan 41. The blower unit 40 is attached to the case 21 so that the axial direction of the rotating shaft 410a, that is, the direction of the rotating shaft of the fan 41 substantially coincides with the Z direction.

The shaft portion 410 has a boss 410b and a magnet 410c in addition to the rotating shaft 410a. The boss 410b has a bottomed cylindrical shape that opens toward the circuit board 30 side in the Z direction and closes toward the other end side. A plurality of blades 411 are provided at equal intervals on the outer peripheral surface of the boss 410b. The blade 411 is located above the peripheral portion of the through hole 211 on the outer surface 21a in the Z direction. The boss 410b and the blade 411 are integrally molded as a so-called impeller.

The rotating shaft 410a is provided inside the boss 410b, and one end thereof is fixed to the substantially center of the boss 410b. The metal rotating shaft 410a is insert-molded into a resin impeller and integrated into the impeller. A magnet 410c is attached to the inner peripheral surface of the boss 410b. As described above, the rotor is configured by including the rotating shaft 410a, the boss 410b, the magnet 410c, and the blade 411.

In addition to the above, the shaft portion 410 includes a bearing (not shown), a bearing holder 410d, a coil 410e, and the like. The bearing rotatably supports the rotary shaft 410a. The bearing holder 410d holds the bearing. The bearing holder 410d projects in the Z direction from the bottom wall 422 of the housing 42, which will be described later. In this embodiment, the bearing holder 410d is integrally provided using the same material as the housing 42. The bearing is arranged on the inner peripheral surface of the bearing holder 410d. The coil 410e is arranged on the outer peripheral surface of the bearing holder 410d. As described above, the stator is configured by including the bearing, the bearing holder 410d, and the coil 410e. That is, the fan 41 has a motor.

The housing 42 rotatably houses the fan 41. The housing 42 is arranged so as to cover the through hole 211 while facing the peripheral portion of the through hole 211 on the outer surface 21a. The housing 42 and the case 21 (bottom wall 210) are watertightly sealed around the entire circumference of the through hole 211. That is, a waterproof structure is also formed around the through hole 211.

A plurality of vents are formed in the housing 42. The plurality of vents are provided so that an air flow along the outer surface 21a of the bottom wall 210 is formed with the rotation of the fan 41 (blades 411). The housing 42 has a first vent 420 and a second vent 421 as a plurality of vents. One of the first vent 420 and the second vent 421 functions as an air inlet, and the other functions as an exhaust port.

Both the first vent 420 and the second vent 421 are formed above the peripheral portion of the through hole 211 on the outer surface 21a, that is, at a position away from the circuit board 30 than the outer surface 21a in the Z direction. In the present embodiment, as described above, the rotation axis of the fan 41 substantially coincides with the Z direction, the first vent 420 is at least partially located above the blades 411, and the second vent 421 is At least a part is formed so as to be located below the blade 411.

The housing 42 of this embodiment has a bottom wall 422 and a side wall 423. The housing 42 is formed using a resin material. The bottom wall 422 and the side wall 423 have a bottomed tubular shape with one end opening in the Z direction. The opening of this cylinder is the first vent 420. The first vent 420 is provided above the blade 411 in the Z direction. The inside of the cylinder is a storage space 42s for accommodating the fan 41. The inner surface of the bottom wall 422 forms the bottom of the accommodation space 42s. The accommodation space 42s is connected to an external space, which is a space outside the waterproof housing 20.

The inner surface of the bottom wall 422 has a substantially rectangular shape in a plane, and the housing 42 has four side walls 423. The four side walls 423 are integrally connected to form a substantially rectangular tubular shape. The side wall 423 is connected to the bottom wall 422. Then, as shown in FIGS. 2 and 3, a second vent 421 is formed on the bottom wall 422. The second vent 421 penetrates the bottom wall 422. In this embodiment, four second vents 421 are formed on the bottom wall 422.

The bottom wall 422 is partitioned by the second vent 421 described above, and has a central portion 422a, an outer edge portion 422b, and a connecting portion 422c. The central portion 422a is a portion provided so as to cover the through hole 211. A sealing member 50 is interposed between the central portion 422a and the peripheral portion of the through hole 221.

The seal member 50 is provided in an annular shape so as to surround the through hole 211. In the present embodiment, a liquid adhesive is used as the sealing member 50 before curing. The blower unit 40 is adhesively fixed to the case 21 by the seal member 50. A seal groove for accommodating the seal member 50 may be provided on the outer surface 21a of the case 21, and a seal protrusion corresponding to the seal groove may be provided on the central portion 422a of the housing 42. Further, a seal protrusion may be provided on the case 21 side, and a seal groove may be provided in the central portion 422a.

The sealing member 50 watertightly seals between the case 21 and the housing 42 all around the through hole 211. Of the central portion 422a, the portion in which the seal member 50 is in close contact corresponds to the watertight sealing portion, and the portion inside the watertight sealing portion is the base portion 422d. Therefore, the central portion 422a includes a watertight sealing portion and a base portion 422d. The central portion 422a has a substantially circular plane shape.

The outer edge portion 422b is an outer edge portion of the bottom wall 422. The side wall 423 is connected to the outer edge portion 422b. The outer edge portions 422b are provided at the four corners of the bottom wall 422 having a substantially rectangular shape in a plane. A second vent 421 is provided between the adjacent outer edge portions 422b. The outer edge portion 422b and the central portion 422a are integrated by a connecting portion 422c. A connecting portion 422c is provided between the adjacent second vents 421 around the rotation axis. The four second vents 421 are formed with four-fold symmetry around the axis of rotation. In the projection view from the Z direction, almost the entire blade 411 is included in one second vent 421.

The bottom wall 422 further has an intermediate wall 422e. The intermediate wall 422e projects from the outer peripheral end of the central portion 422a toward the accommodation space 42s. The intermediate wall 422e is provided in an annular shape so as to surround the rotating shaft 410a.

The terminal 43 projects from the base portion 422d of the bottom wall 422 toward the internal space 20s and is electrically connected to the circuit board 30. One end of the terminal 43 is electrically connected to the fan board 44, and the other end is connected to the circuit board 30. In this way, the fan board 44, that is, the blower unit 40 and the circuit board 30 are electrically connected via the terminal 43.

A drive circuit for rotating the fan 41 is formed on the fan substrate 44. A coil 410e constituting the shaft portion 410 is electrically connected to the fan substrate 44. When the coil 410e is energized through the circuit board 30, the terminal 43, and the fan board 44, the rotor rotates in the positive direction. Then, a pressure difference of air is generated in the housing 42 due to the predetermined shape of the blade 411, and as shown by the alternate long and short dash line in FIG. 2, the air sucked from the first vent 420 is discharged from the second vent 421. , Spreads around the blower unit 40. It is also possible to rotate the rotor in the opposite direction to the forward direction. In this case, the second vent 421 is the suction port and the first vent 420 is the discharge port.

The fan substrate 44 is arranged below the blades 411 in the housing 42. The fan board 44 is fixed to the housing 42. The fan substrate 44 is arranged in a space defined by the central portion 422a and the intermediate wall 422e. The fan substrate 44 is fixed to the central portion 422a by a terminal 43 and a support portion (not shown). A potting body 45 is arranged in the above-mentioned space. The fan substrate 44 is watertightly sealed by the potting body 45.

The fan substrate 44 may be fixed to the inner surface of the central portion 422a. The sealing of the fan substrate 44 is not limited to the potting body 45. For example, the fan substrate 44 on which the terminal 43 is mounted may be insert-molded into the housing 42, and the fan substrate 44 may be sealed by the bottom wall 422.

The breathing filter 60 blocks the flow of liquid while allowing the flow of gas. The breathing filter 60 prevents the liquid from entering the internal space 20s from the external space through the vent 212. As the liquid, rainwater, water used for car washing (for example, high-pressure washing water), water rolled up when the vehicle is running, a solution of calcium chloride used as a snow melting agent by melting snow, an organic solvent such as brake oil, etc. are assumed. .. The breathing filter 60 is attached to the case 21 so as to close the ventilation holes 212. Details of the breathing filter 60 will be described later together with the ventilation holes 212.

Next, the ventilation holes 212 and the breathing filter 60 will be described with reference to FIGS. 2 and 3.

The breathing filter 60 of the present embodiment has only the ventilation membrane 61. The breathable membrane 61 is waterproof and breathable. The breathable membrane 61 has water repellency and oil repellency. As the air-permeable membrane 61, for example, a porous membrane formed by using fluororesin or polyolefin can be adopted. The ventilation film 61 is attached to the outer surface 21a of the bottom wall 210 of the case 21 so as to close the ventilation holes 212. Such a breathing filter 60 is also referred to as a seal filter.

The ventilation hole 212 is provided in the bottom wall 210 of the case 21 and communicates the internal space 20s with the external space. The ventilation hole 212 is a region outside the watertight sealing portion of the projection region of the blower unit 40 in the case 21 in the Z direction, and is formed on the air flow path accompanying the rotation of the fan 41. .. In this embodiment, the vent holes 212 are formed in the projected region of the second vent 421 in the case 21. Further, the ventilation hole 212 is formed in the projection region of the blade 411. One vent hole 212 is formed in the case 21.

As a result, the ventilation film 61 is arranged in the projection region of the second ventilation port 421 in the case 21. Further, the ventilation film 61 is arranged in the projection region of the blade 411. The electronic device 10 is provided with one breathing filter 60.

Next, an example of the procedure for assembling the electronic device 10 described above will be described.

First, the case 21, the cover 22, and the blower unit 40 are prepared. At this time, the case 21 provided with the breathing filter 60 described above is prepared.

Next, the blower unit 40 is attached to the case 21. Next, the electronic device 10 can be obtained by connecting the terminal 43 and the circuit board 30 and assembling the cover 22 to the case 21.

Further, when a press-fit terminal is adopted as the terminal 43, for example, after assembling the case 21 and the cover 22 with the circuit board 30 housed, the blower unit 40 can be connected to the circuit board 30 while being fixed to the case 21. can.

Next, the effect of the electronic device 10 described above will be described.

In this electronic device 10, the air flow is forcibly created by the blower unit 40, and the case 21 of the waterproof housing 20 can be cooled. The blower unit 40 is superior in heat dissipation to the heat dissipation fins. Therefore, the physique of the electronic device 10 can be made smaller than in the case where the heat radiating fins are provided in order to secure the heat radiating property equivalent to that of the blower unit 40.

Further, a through hole 211 is provided in the case 21 to attach the blower unit 40, and the blower unit 40 and the circuit board 30 are connected via a terminal 43 protruding from the base portion 422d of the housing 42 into the internal space 20s. Therefore, the circuit board 30 and the blower unit 40 are connected via a wire harness or the like provided outside the waterproof housing 20, or another device provided in the vehicle and the blower unit 40 are electrically connected. There is no need to do it. Therefore, it is possible to suppress imposing mounting restrictions on the vehicle side. Further, by adopting the connection structure by the terminal 43, the configuration of the electronic device 10 can be simplified, and the physique can also be reduced by this. Further, the man-hours for electrically connecting the blower unit 40 to the circuit board 30 can be reduced.

Further, a ventilation hole 212 is provided in the projection area of the blower unit 40 in the case 21. Therefore, the ventilation unit 40 can prevent the water that the vehicle winds up during traveling, the water used for washing the vehicle, and the like from hitting the breathing filter 60 (ventilation membrane 61). Specifically, the fan 41 and the housing 42 serve as a protective wall against the water shown by the alternate long and short dash line in FIG. 2, and it is possible to prevent the fan 41 and the housing 42 from directly hitting the breathing filter 60. In addition, it is possible to prevent water from entering the periphery of the respiratory filter 60.

Further, the ventilation holes 212, and thus the breathing filter 60, are provided on the air flow path accompanying the rotation of the fan 41, that is, on the ventilation path. Therefore, as shown in FIG. 2, even if the water 100 stays around the breathing filter 60, it can be blown off from the breathing filter 60 by the air flow. That is, it can be drained. As described above, it is possible to suppress the water contact of the ventilation film 61. Thereby, for example, it is possible to suppress that the ventilation between the internal space 20s and the external space is blocked.

As described above, according to the electronic device 10 of the present embodiment, it is possible to reduce the size of the physique while suppressing the imposition of mounting restrictions on the vehicle side, and to suppress the water exposure of the ventilation membrane 61.

Further, in the present embodiment, the blower unit 40 is fixed to the case 21 so that the rotation axis of the fan 41 substantially coincides with the Z direction. Therefore, the physique in the Z direction can be made smaller than that in the case where the rotation axis is orthogonal to the Z direction in the case. In addition, the first vent 420 is formed above the blade 411, and the second vent 421 is formed below the blade 411. As a result, an air flow is formed along the outer surface 21a of the case 21 with the rotation of the fan 41, and the case 21 and the circuit board 30 can be efficiently cooled.

Further, a second vent 421 is provided on the bottom wall 422, and a vent 212 and a breathing filter 60 are provided in the projection region of the second vent 421 in the case 21. That is, the first vent 420 and the second vent 421 are arranged side by side in the direction of the rotation axis of the fan 41. Therefore, the air flow accompanying the rotation of the fan 41 can be efficiently applied to the breathing filter 60.

Further, since the ventilation hole 212 and the breathing filter 60 are provided in the projection region of the blade 411, in other words, directly below, it is possible to prevent high-pressure washing water or the like from directly hitting the breathing filter 60 (ventilation membrane 61). be able to. For example, peeling of the ventilation film 61 can be suppressed.

Further, in the present embodiment, the first vent 420 is a suction port and the second vent 421 is a discharge port. According to this, the flow velocity on the outer surface 21a of the case 21 can be increased even at the same rotation speed as compared with the configuration in which the second vent 421 is the suction port and the first vent 420 is the discharge port. That is, the temperature of the case 21, and thus the circuit board 30, can be lowered. This point has been confirmed by simulation.

In the configuration in which the bottom wall of the case is not provided with a through hole as described above, the connector and the harness hinder cooling, and the arrangement of electronic components such as heat generating elements is also restricted. On the other hand, in the present embodiment, since the connector and the harness are not obstructed, the degree of freedom in arranging the electronic component 32 can be improved.

Further, in this embodiment, four second vents 421 are formed on the bottom wall 422 of the housing 42 so as to surround the rotation shaft so as not to interfere with the connector and the harness. As a result, the air sucked from the first vent 420 spreads in all directions on the outer surface 21a of the case 21 through the four second vents 421. Therefore, the case 21 can be effectively cooled.

In the present embodiment, an example in which the respiratory filter 60 has only the ventilation membrane 61 is shown, but the present invention is not limited to this. In the modified example shown in FIG. 4, the breathing filter 60 has a filter case 62, a filter cover 63, and a sealing member 64 in addition to the ventilation membrane 61.

The filter case 62 is formed by using a resin material. The filter case 62 has a tubular shape with both ends open. The filter case 62 has a locking projection on one end side, and is fixed to the bottom wall 210 of the case 21 with one end side inserted into the ventilation hole 212. A ventilation membrane 61 is fixed to the other end side of the filter case 62 so as to close the opening of the filter case 62.

The filter cover 63 protects the ventilation film 61. The filter cover 63 is arranged so as to cover the ventilation film 61. The filter cover 63 has a box shape in which the surface on the ventilation film 61 (filter case 62) side is open. A vent 63a is formed in a part of the side wall of the filter cover 63. The filter cover 63 is fixed to the filter case 62, and the ventilation film 61 is arranged in the space defined by the filter cover 63 and the filter case 62.

The sealing member 64 watertightly seals between the filter case 62 and the case 21. In this embodiment, a rubber-like elastic body is used as the sealing member 64. The seal member 64 is sandwiched between the filter case 62 and the case 21.

As described above, even if the respiratory filter 60 having the filter cover 63 is adopted, the same effect as that of the prior embodiment can be obtained. Further, the filter cover 63 can prevent the washing water and the like from directly hitting the ventilation film 61.

(Second Embodiment)
In this embodiment, the preceding embodiment can be referred to. Therefore, the description of the parts common to the electronic device 10 shown in the preceding embodiment will be omitted.

As shown in FIG. 5, in the present embodiment, the blower unit 40 further includes a flow path forming portion 46. The flow path forming portion 46 is arranged in a portion of the outer surface 21a of the case 21 in the projection region of the second vent 421, and together with the outer surface 21a, passes through the flow path 47 through which the air flow accompanying the rotation of the fan 41 passes. Is forming. That is, air (cooling air) flows in the flow path 47. The ventilation hole 212 is formed in a portion of the case 21 whose outer surface 21a constitutes the flow path 47. The ventilation hole 212 is open to the flow path 47. A breathing filter 60 is arranged in the flow path 47.

The flow path forming portion 46 extends along the X direction. The flow path forming portion 46 extends along the ventilation path on the outer surface 21a. As shown in FIG. 6, the flow path forming portion 46 has an upper wall 460 and a side wall 461. Side walls 461 are connected to both ends of the upper wall 460 in the width direction. As a result, the flow path forming portion 46 has a substantially U-shaped cross section orthogonal to the extending direction. Then, the end portion of the side wall 461 opposite to the upper wall 460 is arranged on the outer surface 21a, and a flow path 47 having a substantially rectangular cross section is formed. The inner surface 460a of the upper wall 460 faces the outer surface 21a of the case 21. The inner surface 460a is substantially parallel to the outer surface 21a in the overall length of the flow path 47. Further, the cross-sectional area of the flow path 47 is also substantially constant over the total length.

In the present embodiment, as shown in FIGS. 5 and 7, the flow path forming portion 46 is provided integrally with the housing 42. As a result, the assembly man-hours can be reduced. The flow path forming portion 46 may be integrally formed with the housing 42, or the flow path forming portion 46 formed separately from the housing 42 may be fixed to the housing 42. One end of the flow path forming portion 46 is connected to the lower end of the side wall 423, and the other end is open to the accommodation space 42s. Other than that, it has the same configuration as the previous embodiment.

As described above, in the present embodiment, the flow path 47 is formed by the flow path forming portion 46 and the outer surface 21a, and the respiration filter 60 is arranged in the flow path 47. The flow path 47 can narrow the cross-sectional area of the space in which the breathing filter 60 is arranged and increase the flow velocity. Therefore, it is possible to suppress the retention of water around the respiration filter 60 as compared with the configuration having no flow path 47. That is, the water exposure of the ventilation membrane 61 can be effectively suppressed.

Further, since the flow path forming portion 46 covers the breathing filter 60, it is possible to prevent the washing water or the like from directly hitting the ventilation membrane 61.

Further, in the present embodiment, the inner surface 460a of the upper wall is substantially parallel to the outer surface 21a in the total length of the flow path 47. As a result, it is possible to suppress the occurrence of turbulent flow in the flow path 47. That is, it is possible to suppress the air flow accompanying the rotation of the fan 41 from staying around the breathing filter 60 and enhance the drainage effect.

Although the example in which the flow path forming portion 46 is connected to the side wall 423 is shown, the present invention is not limited to this. For example, it may be connected to the bottom wall 422. Further, the flow path forming portion 46 may be provided independently (separated) from the housing 42.

(Third Embodiment)
In this embodiment, the preceding embodiment can be referred to. Therefore, the description of the parts common to the electronic device 10 shown in the preceding embodiment will be omitted.

In the second embodiment, an example is shown in which the flow path forming portion 46 is arranged in the projection region of the second vent 421, and the flow velocity around the breathing filter 60 is increased by the Venturi effect. On the other hand, in the present embodiment, as shown in FIGS. 8 to 10, the housing 42 of the blower unit 40 further has an extension portion 424 extending from the outer surface of the side wall 423. The extension portion 424 forms a flow path 425 through which the air flow accompanying the rotation of the fan 41 passes, together with the outer surface 21a of the case 21. That is, air (cooling air) flows in the flow path 425. The ventilation hole 212 is open to the flow path 425. Then, the respiration filter 60 is arranged in the flow path 425.

The extension portion 424 is extended along the X direction. One end of the extension portion 424 is connected to the lower end of the side wall 423. The extension portion 424 extends along the ventilation path on the outer surface 21a. The extension portion 424 is configured in the same manner as the flow path forming portion 46 described above. As shown in FIG. 9, the extension portion 424 has an upper wall 424a and a side wall 424b. Side walls 424b are connected to both ends of the upper wall 424a in the width direction. As a result, the extension portion 424 has a substantially U-shaped cross section orthogonal to the extension direction. Then, the end portion of the side wall 424b opposite to the upper wall 424a is arranged on the outer surface 21a to form a flow path 425 having a substantially rectangular cross section. The inner surface 424c of the upper wall 424a faces the outer surface 21a of the case 21. The inner surface 424c is substantially parallel to the outer surface 21a in the overall length of the flow path 425. Further, the cross-sectional area of the flow path 425 is also substantially constant over the total length. Other than that, it has the same configuration as that of the second embodiment.

Even with the above configuration, the same effect as that of the configuration shown in the second embodiment can be obtained.

(Fourth Embodiment)
In this embodiment, the preceding embodiment can be referred to. Therefore, the description of the parts common to the electronic device 10 shown in the preceding embodiment will be omitted.

As shown in FIG. 11, in the present embodiment, the fan 41 further has a protrusion 412 that projects toward the breathing filter 60 and rotates integrally with the blades 411.

The protruding portion 412 is connected to, for example, the outer peripheral surface of the boss 410b. The protruding portion 412 is fixed to the outer peripheral surface of the boss 410b by, for example, adhesion. The protruding portion 412 has a first portion extending in the radial direction orthogonal to the rotation axis from the outer peripheral surface of the boss 410b, and a second portion extending in the Z direction from the tip of the first portion. With the protrusion 412 stopped directly above the breathing filter 60, there is a slight gap between the tip surface of the protrusion 412 and the breathing filter 60. As a result, the protrusion 412 rotates in a non-contact manner with respect to the respiratory filter 60. Other than that, it has the same configuration as the modified example (see FIG. 4).

As described above, in the present embodiment, the fan 41 has a protruding portion 412 that rotates integrally with the blade 411, and the rotating protruding portion 412 repels the water that stays on the breathing filter 60. can. Therefore, it is possible to suppress the water contact of the ventilation film 61.

In the present embodiment, the same effect as that of the first embodiment can be obtained. That is, the ventilation unit 40 can prevent the water that the vehicle winds up during traveling, the water used for washing the vehicle, and the like from hitting the breathing filter 60. Further, the water 100 can be blown off from the breathing filter 60 by the air flow accompanying the rotation of the fan 41. Therefore, in combination with the effect of the protruding portion 412, the water exposure of the ventilation film 61 can be effectively suppressed.

In this embodiment, the ventilation hole 212 and the breathing filter 60 are provided on the ventilation path in the projection region of the ventilation unit 40, which is the region outside the watertight sealing portion. , Not limited to this. The ventilation holes 212 and the breathing filter 60 may be in the projection area of the ventilation unit 40, which is outside the watertight sealing portion. Even if it is not on the ventilation path, the water contact of the ventilation film 61 can be suppressed by the rotation of the protrusion 412.

Disclosure of this specification is not limited to the illustrated embodiments. The disclosure includes exemplary embodiments and modifications by those skilled in the art based on them. For example, disclosure is not limited to the combination of elements shown in the embodiments. Disclosure can be carried out in various combinations. The technical scope disclosed is not limited to the description of the embodiments. Some technical scopes disclosed are indicated by the description of the claims and should be understood to include all modifications within the meaning and scope equivalent to the description of the claims. ..

As the electronic device 10, an example of an electronic control device that controls a vehicle engine has been shown, but the electronic device 10 is not limited thereto.

An example in which the terminal 43 is inserted and mounted on the circuit board 30 has been shown, but the present invention is not limited to this. A surface mount structure can also be adopted.

An example is shown in which the housing 42 is adhesively fixed to the case 21 by the sealing member 50, but the present invention is not limited to this. When other fixing means are adopted, a rubber-like elastic body or the like can be adopted as the sealing member 50.

The case 21 may be provided with heat radiation fins. That is, the blower unit 40 and the heat radiation fin may be used together.

The positions of the first vent 420 and the second vent 421 are not limited to the above examples. The first vent 420 and the second vent 421 may be provided so that the air flow along the outer surface 21a of the bottom wall 210 in the case 21 is formed with the rotation of the fan 41. A part of the side wall 423 may be cut out together with the bottom wall 422 of the housing 42 to form a second vent 421. Even if the second vent 421 is provided on the side wall 423, a through hole different from the second vent 421 is provided on the bottom wall 422, and the vent 212 and the breathing filter 60 are provided in the projected area of the through hole. good.

10 ... Electronic device, 20 ... Waterproof housing, 20s ... Internal space, 21 ... Case, 21a ... Outer surface, 21b ... Inner surface, 210 ... Bottom wall, 211 ... Through hole, 212 ... Vent hole, 213 ... First accommodating part, 214 ... 2nd accommodating part, 215 ... mounting part, 216 ... fixing hole, 22 ... cover, 220 ... heat dissipation fin, 30 ... circuit board, 31 ... printed circuit board, 31a ... one side, 31b ... back side, 32 ... electronic component, 32a ... Heat generating element, 32b ... Atmospheric pressure sensor, 33 ... Connector, 40 ... Blower unit, 41 ... Fan, 410 ... Shaft, 410a ... Rotating shaft, 410b ... Boss, 410c ... Magnet, 410d ... Bearing holder, 410e ... Coil, 411 ... blades, 412 ... protrusions, 42 ... housing, 42s ... accommodation space, 420 ... first vent, 421 ... second vent, 422 ... bottom wall, 422a ... central part, 422b ... outer edge part, 422c ... connection Part, 422d ... Base part, 422e ... Intermediate wall, 423 ... Side wall, 424 ... Extension part, 424a ... Upper wall, 424b ... Side wall, 424c ... Opposing surface, 425 ... Flow path, 43 ... Terminal, 44 ... Fan board, 45 ... potting body, 46 ... flow path forming part, 460 ... upper wall, 460a ... facing surface, 461 ... side wall, 47 ... flow path, 50 ... sealing member, 60 ... breathing filter, 61 ... ventilation film, 62 ... filter case , 63 ... Filter cover, 63a ... Vent, 64 ... Seal member, 100 ... Water

Claims (10)

An electronic device mounted on a vehicle
A waterproof housing (20) having a wall portion (210) formed with a through hole (211), and a waterproof housing (20).
The circuit board (30) housed in the internal space of the waterproof housing and
A fan (41) including a blade (411) and a member that rotatably accommodates the fan, and the wall portion covers the through hole while facing the peripheral portion of the through hole on the outer surface of the wall portion. From a housing (42) arranged in a watertightly sealed space around the through hole and watertightly sealed between the wall portion and a base portion (422d) which is an inner portion of the watertightly sealed portion in the housing. The housing is provided so that a terminal (43) projecting into the internal space and electrically connected to the circuit board and an air flow along the outer surface of the wall portion are formed as the fan rotates. A blower unit (40) having a plurality of vents (420, 421) and
The flow of liquid between the external space and the internal space while allowing the flow of gas between the external space and the internal space, which is arranged in the waterproof housing and is the space outside the waterproof housing. Breathing filter (60) that blocks
With
The waterproof housing communicates the external space and the internal space at the wall portion, and is a region outside the watertight sealing portion of the projected region of the blower unit in the plate thickness direction of the circuit board. It has a vent (212) formed on the path of the air flow accompanying the rotation of the fan.
An electronic device including a ventilation membrane (61) in which the breathing filter is arranged on the outer surface side of the wall portion so as to close the ventilation holes. The rotation axis of the fan coincides with the thickness direction of the circuit board,
The housing includes the base portion and has a bottom wall portion (422) arranged to face the outer surface of the wall portion and a side wall portion (423) connected to the bottom wall portion.
The ventilation unit has at least a part of the first vent (420) provided at a position farther than the blade with respect to the circuit board as the vent, and at least a part of the vent is closer to the blade. The electronic device according to claim 1, further comprising a second vent (421) provided. The second vent is formed on the outside of the watertightly sealed portion of the bottom wall portion.
The electronic device according to claim 2, wherein the breathing filter is arranged in the projection region of the second vent on the wall portion. The electronic device according to claim 3, wherein the breathing filter is arranged in a projection region of the blade. The ventilation unit is arranged on the outer surface of the wall portion in the projection region of the second vent, and together with the outer surface, forms a flow path (47) through which the air flow accompanying the rotation of the fan passes. It has a forming portion (46) and has a forming portion (46).
The electronic device according to claim 3 or 4, wherein the breathing filter is arranged in the flow path. The electronic device according to claim 5, wherein the flow path forming portion is provided integrally with the housing. The electronic device according to claim 5 or 6, wherein the surface (460a) facing the wall portion in the flow path forming portion is parallel to the outer surface of the wall portion in the total length of the flow path. The housing extends from the outer surface of the side wall and is arranged on the outer surface of the wall portion, and together with the outer surface, an extension portion (425) forming a flow path (425) through which an air flow accompanying the rotation of the fan passes. 424) and
The electronic device according to claim 2, wherein the breathing filter is arranged in the flow path. The electronic device according to claim 3 or 4, wherein the fan projects toward the breathing filter and has a projecting portion (412) that rotates integrally with the blade. An electronic device mounted on a vehicle
A waterproof housing (20) having a wall portion (210) formed with a through hole (211), and a waterproof housing (20).
The circuit board (30) housed in the internal space of the waterproof housing and
A fan (41) including a blade (411) and a member that rotatably accommodates the fan, and the wall portion covers the through hole while facing the peripheral portion of the through hole on the outer surface of the wall portion. From a housing (42) arranged in a watertightly sealed space around the through hole and watertightly sealed between the wall portion and a base portion (422d) which is an inner portion of the watertightly sealed portion in the housing. The housing is provided so that a terminal (43) projecting into the internal space and electrically connected to the circuit board and an air flow along the outer surface of the wall portion are formed as the fan rotates. A blower unit (40) having a plurality of vents (420, 421) and
The flow of liquid between the external space and the internal space while allowing the flow of gas between the external space and the internal space, which is arranged in the waterproof housing and is the space outside the waterproof housing. Breathing filter (60) that blocks
With
The waterproof housing communicates the external space and the internal space at the wall portion, and is located in a region outside the watertight sealing portion of the projected region of the blower unit in the plate thickness direction of the circuit board. It has a formed vent (212) and
The breathing filter includes a ventilation membrane (61) arranged on the outer surface side of the wall portion so as to close the ventilation holes.
An electronic device in which the fan projects toward the breathing filter and has a protrusion (412) that rotates integrally with the blade.

Images