Power Unit

Abstract

To reduce the number of components constituting a power unit.SOLUTION: A power unit may comprise: a high-voltage circuit; a cashing which accommodates the high-voltage circuit and has a service hole on a first surface; a connector which is attachably / detachably attached to a second surface different from the first surface of the casing and electrically connected with the high-voltage circuit; and a cover which is attached in a range stretching from the first surface to the second surface of the casing, closes the service hole and covers at least a part of the connector.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a power unit. [Background technology]

[0002] Patent Document 1 describes an electric power unit for a vehicle. The electric power unit includes a power converter including a high-voltage circuit, a casing that houses the power converter, and a connector that is attached to the casing and electrically connected to the power converter. The electric power unit is provided with a protector that covers the connector to protect it in the event of a vehicle collision. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2020-89189 Summary of the Invention [Problem to be solved by the invention]

[0004] In power units such as those described above, service holes are often provided in the casing. A service hole is a window (opening) provided in the casing for the purpose of inspecting high-voltage circuits, replacing parts, assembling parts, etc. In this case, a service cover for closing the service hole must also be attached to the casing in addition to the protector for collision protection described above. As a result, the number of parts that make up the power unit increases, and so does the labor required for their installation. Therefore, this specification provides a technology that can reduce the number of parts that make up a power unit. [Means for solving the problem]

[0005] The technology disclosed in this specification is embodied in a power unit. In a first aspect, the power unit may include a high-voltage circuit, a casing that houses the high-voltage circuit and has a service hole on a first surface, a connector that is detachably attached to a second surface of the casing that is different from the first surface and is electrically connected to the high-voltage circuit, and a cover that is attached to a range from the first surface to the second surface of the casing, closing the service hole and covering at least a portion of the connector.

[0006] In the power unit described above, the service cover that closes the service hole and the protector that protects the connector are integrated into the cover, which reduces the number of parts in the power unit and also reduces the labor required to install them.

[0007] In a second aspect, in the first aspect described above, the first surface may be the top surface of the casing, and the second surface may be a side surface adjacent to the top surface. With this configuration, the service hole and the connector covered by the cover are located relatively close to each other. Therefore, the dimensions of the cover are not unnecessarily enlarged, and a decrease in the rigidity of the cover can be avoided.

[0008] In a third aspect, in the second aspect described above, the cover may have an upper wall portion extending from the first surface and passing above the connector, and a vertical wall portion extending downward from the upper wall portion. In this case, the vertical wall portion may have a first portion facing the second surface of the casing via the connector, and a pair of second portions extending from both ends of the first portion toward the second surface of the casing, thereby covering the connector from three directions. With this configuration, the connector is protected from three directions, and the three-dimensional shape of the cover can also increase the rigidity of the cover.

[0009] In a fourth aspect, in any of the first to third aspects described above, a rib may be provided on the first surface of the casing, protruding toward the cover and running around the periphery of the service hole. In this case, a gasket may be interposed between the cover and the rib. This configuration effectively prevents or inhibits moisture accumulated on the casing from entering the inside of the cover through the service hole. Furthermore, since the gasket is disposed on the rib, moisture on the casing (which often contains salt) is prevented from coming into contact with the gasket for a long period of time. Furthermore, in the configuration according to the present technology, the area of ​​the cover is relatively large compared to the size of the service hole (i.e., the size of the gasket), and the cover overhangs significantly relative to at least a portion of the gasket. These configurations also inhibit deterioration of the gasket due to contact with moisture, etc.

[0010] In a fifth aspect, in any one of the first to fourth aspects, the power unit may be a power unit mounted on a vehicle. In this case, the high-voltage circuit may include a power conversion circuit that performs power conversion between a power source of the vehicle and a traction motor. However, the power unit is not limited to being mounted on the vehicle, and may be mounted on, for example, another mobility device or a stationary device. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view schematically illustrating a power unit, with detailed configurations of the power unit not shown. [Figure 2] 1 is a cross-sectional view showing a schematic configuration of a casing and a cover attached to the casing, in which a connector is shown by a broken line and a power conversion device inside the casing is not shown. [Figure 3] FIG. 2 is a diagram schematically illustrating the configuration of a cover. DETAILED DESCRIPTION OF THE INVENTION [Example]

[0012] An electric power unit according to an embodiment will be described with reference to the drawings. The electric power unit is mounted on a vehicle. The electric power unit supplies drive power from the vehicle's power source to a motor that drives the vehicle. However, the electric power unit is not limited to being mounted on a vehicle, and may be mounted on, for example, other mobility devices or stationary devices. In one example, the electric power unit is disposed in a front compartment located at the front of the vehicle body. The power source is disposed, for example, under the floor of the vehicle body.

[0013] Here, the directions of the power unit in the drawings correspond to the directions when it is mounted on a vehicle, i.e., the directions of the vehicle. Therefore, the direction FR indicates the front in the longitudinal direction of the vehicle, and the direction RR indicates the rear in the longitudinal direction of the vehicle. The direction LH indicates the left in the lateral direction of the vehicle, and the direction RH indicates the right in the lateral direction of the vehicle. The direction UP indicates the upward direction in the vertical direction of the vehicle, and the direction DW indicates the downward direction in the vertical direction of the vehicle.

[0014] As shown in Fig. 1, the power unit 10 includes a power converter 20, a casing 12, a power connector 14, an auxiliary connector 16, and a cover 18. The power converter 20 converts power between the vehicle and the motor. The power converter 20 includes high-voltage circuits such as step-up and step-down converter circuits and an inverter circuit. Here, high voltage means a DC voltage exceeding 60 volts or an AC voltage exceeding 30 volts (effective value).

[0015] The casing 12 houses the power conversion device 20. The casing 12 has a generally rectangular parallelepiped shape. The casing 12 has a top surface 12a, four side surfaces 12b, 12c, 12d, and 12e adjacent to the top surface 12a, and a bottom surface (not shown). The four side surfaces 12b-12e include, for example, a rear surface 12b, a right surface 12c, a front surface 12d, and a left surface 12e. The top surface 12a of the casing 12 has multiple service holes 12h. As shown in FIG. 2, each service hole 12h is formed to allow access from the outside to the inside of the casing 12. Therefore, a worker performing maintenance on the power unit 10 can inspect the power conversion device 20 (i.e., the high-voltage circuit), replace parts, assemble parts, and so on through these service holes 12h.

[0016] A power connector 14 is detachably attached to the rear surface 12b of the casing 12. The power connector 14 is electrically connected to the high-voltage circuit of the power conversion device 20. The power connector 14 is electrically connected to the vehicle's power supply via a power cable 15. Specifically, the power connector 14 has a negative connector 14a and a positive connector 14b. The negative connector 14a is electrically connected to the negative pole of the power supply, and the positive connector 14b is electrically connected to the positive pole of the power supply. In other words, the power connector 14 electrically connects the vehicle's power supply and the high-voltage circuit of the power conversion device 20 to each other. Although not shown, a connector for connecting the motor and the power conversion device 20 is also detachably attached to the casing 12. This allows the power unit 10 to supply drive power from the vehicle's power supply to the motor that runs the vehicle.

[0017] Here, the top surface 12a of the casing 12 is an example of the "first surface" in the technology disclosed herein, and the rear surface 12b of the casing 12 is an example of the "second surface" in the technology disclosed herein. However, the second surface is not limited to the rear surface 12b, and may be provided on another surface. The second surface may be any surface different from the first surface (i.e., the top surface 12a in this embodiment) in which the service hole 12h is formed.

[0018] As an example, an auxiliary connector 16 is detachably attached to the rear surface 12b of the casing 12. The auxiliary connector 16 is electrically connected to a high-voltage circuit (e.g., a step-down converter circuit) of the power conversion device 20. The auxiliary connector 16 is connected to other internal devices of the vehicle, such as an air conditioner compressor. Therefore, the power unit 10 can also function as a distributor that distributes power supplied from the power source to the other internal devices.

[0019] As shown in Figures 1 and 2, the cover 18 is detachably attached to the casing 12. The cover 18 is disposed in a range from the top surface 12a to the rear surface 12b of the casing 12. The cover 18 is fixed to the casing 12 using fastening members such as a plurality of bolts 24. The cover 18 closes the plurality of service holes 12h and covers the power connector 14. In other words, in the power unit 10 of this embodiment, the service cover that closes the plurality of service holes 12h and the protector that protects the power connector 14 are integrated into the cover 18. This configuration reduces the number of parts of the power unit 10 and also reduces the labor required to install them.

[0020] As described above, the cover 18 of this embodiment is disposed in a range extending from the top surface 12a of the casing 12 to the rear surface 12b adjacent to the top surface 12a. With this configuration, the service hole 12h covered by the cover 18 and the power connector 14 are located relatively close to each other. Therefore, the dimensions of the cover 18 are not unnecessarily enlarged, and a decrease in the rigidity of the cover 18 can be avoided.

[0021] Next, the configurations of the casing 12 and the cover 18 will be described in detail. As shown in FIG. 2, a rib 12r protruding toward the cover 18 is provided on the top surface 12a of the casing 12. The rib 12r has a ridge-like shape and extends around the periphery of the service hole 12h. A gasket 22 is interposed between the cover 18 and the rib 12r. The gasket 22 has an annular shape and is made of a viscoelastic material, such as rubber. The gasket 22 is disposed in an annular groove 18g provided on the surface of the cover 18 facing the service hole 12h of the casing 12. This configuration effectively prevents or inhibits moisture accumulated on the casing 12, i.e., on the top surface 12a, from penetrating into the cover 18 through the service hole 12h. Furthermore, because the gasket 22 is disposed on the rib 12r of the casing 12, prolonged contact of moisture (which often contains salt) on the casing 12 with the gasket 22 is prevented.

[0022] Furthermore, in the power unit 10 of this embodiment, the area of ​​the cover 18 is relatively large compared to the size of the service hole 12h of the casing 12 (i.e., the size of the gasket 22). Therefore, the cover 18 protrudes significantly beyond at least a portion of the gasket 22. These configurations also suppress deterioration of the gasket 22 due to contact with moisture, etc.

[0023] The cover 18 is a plate member. As shown in FIG. 1-3 , the cover 18 has an upper wall portion 18a and vertical wall portions. The upper wall portion 18a extends from the top surface 12a of the casing 12, passing above the power connector 14. The vertical wall portions extend downward from the upper wall portion 18a. The vertical wall portions include a rear wall portion 18b, a right wall portion 18c, and a left wall portion 18d. The rear wall portion 18b faces the rear surface 12b of the casing 12 across the power connector 14. The right wall portion 18c and the left wall portion 18d extend from the left and right ends of the rear wall portion 18b toward the rear surface 12b of the casing 12. Therefore, the vertical wall portions of the cover 18 cover the power connector 14 from three directions. With this configuration, the power connector 14 is protected from three directions, and the three-dimensional shape of the cover 18 also increases the rigidity of the cover 18.

[0024] Regarding the vertical wall portions of the cover 18, the rear wall portion 18b is an example of a "first portion" in the technology disclosed herein, and the right wall portion 18c and the left wall portion 18d are an example of a "pair of second portions" in the technology disclosed herein. However, the configuration of the cover 18 is not limited to the configuration of the embodiment. The cover 18 does not have to cover the power connector 14 from three directions using only the vertical wall portions. The vertical wall portions of the cover 18 may cover the power connector 14 from three directions together with the top wall portion 18a. In this case, the vertical wall portions of the cover 18 may include, for example, only the rear wall portion 18b and the right wall portion 18c or the left wall portion 18d, or only the right wall portion 18c and the left wall portion 18d. Even with such a configuration, the rigidity of the cover 18 can be relatively increased.

[0025] Although not particularly limited, the cover 18 can be formed using a material having excellent rigidity. The material forming the cover 18 may be, for example, cast iron, aluminum casting, pressed iron plate, resin (including fiber reinforced plastic (FRP) and carbon fiber reinforced plastic (CFRP)), etc.

[0026] 1, the cover 18 in this embodiment covers both the negative connector 14a and the positive connector 14b of the power connector 14. However, this is not limited to this, and the cover 18 may cover only one of the negative connector 14a and the positive connector 14b of the power connector 14. Alternatively, the cover 18 may cover not only the power connector 14 but also another connector arranged adjacent thereto, such as the auxiliary connector 16. Furthermore, the number of service holes 12h covered by the cover 18 in this embodiment is not limited to two, and may be one or three or more service holes 12h.

[0027] Although specific examples of the technology disclosed in this specification have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or in the drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. The technology exemplified in this specification or in the drawings can achieve multiple objectives simultaneously, and achieving one of these objectives itself has technical utility. [Explanation of symbols]

[0028] 10: power unit, 12: casing, 12a: top surface, 12b: rear surface, 12h: service hole, 12r: rib, 14: power connector, 18: cover, 18a: top wall portion, 18b: rear wall portion, 18c: right wall portion, 18d: left wall portion, 20: power conversion circuit, 22: gasket

Claims

1. A high voltage circuit; a casing that houses the high voltage circuit and has a service hole on a first surface; a connector detachably attached to a second surface of the casing, the second surface being different from the first surface, and electrically connected to the high-voltage circuit; a cover attached to the casing in a range from the first surface to the second surface, closing the service hole and covering at least a portion of the connector; A power unit comprising:

2. the first surface is a top surface of the casing, The power unit of claim 1 , wherein the second surface is a side surface adjacent to the top surface.

3. the cover has an upper wall portion extending from the first surface to pass above the connector, and a vertical wall portion extending downward from the upper wall portion, 3. The power unit according to claim 2, wherein the vertical wall portion has a first portion that faces the second surface of the casing via the connector, and a pair of second portions that extend from both ends of the first portion toward the second surface of the casing, thereby covering the connector from three directions.

4. a rib that protrudes toward the cover and extends around the periphery of the service hole is provided on the first surface of the casing, The power unit according to claim 1 , wherein a gasket is interposed between the cover and the rib.

5. the power unit is an power unit mounted on a vehicle, The power unit according to claim 1 , wherein the high-voltage circuit includes a power conversion circuit that performs power conversion between a power supply and a traction motor of the vehicle.

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