Power converter

A power convertor has a casing and a power conversion circuit arranged in an internal chamber of the casing. The casing has a first wall member as a specific side wall. A plurality of connector opening parts are formed in the first wall member. At least two of the plurality of connector opening parts formed in the first wall member are arranged at different positions facing a different direction from each other.

CROSS-REFERENCE TO RELATED APPLICATION

This application is related to and claims priority from Japanese Patent Application No. 2018-218057 filed on Nov. 21, 2018, the contents of which are hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to power convertors.

BACKGROUND

There are known power converters which convert electric power of an electric power source to a drive electric power to be supplied to a drive motor mounted on a motor vehicle. The power converter is arranged on a transaxle arranged at a front compartment of the motor vehicle.

The power converter is covered with a casing. The casing has a bottom wall, side walls and a ceiling wall. The bottom wall is arranged at a bottom side of the power converter. The side walls stand on the bottom wall. The ceiling wall is arranged at the upper side of the side walls to close the power converter and to form a box shape. Various types of connectors have a plurality of opening parts formed in one side wall in the overall side walls. Through the plurality of opening parts of the connectors, the power converter is electrically connected to the drive motor, and the power converter is also electrically connected to a controller.

However, the power converter previously described has the plurality of opening parts formed in one side wall which are open in a vehicle-width direction. This reduces an overall area of the side wall in the vehicle-width direction. That is, this structure often reduces an overall strength of the casing of the power converter.

SUMMARY

It is desired for the present disclosure to provide a power converter having a casing and a power conversion circuit. An internal chamber is formed in the casing. The power conversion circuit is arranged in the internal chamber of the casing. The casing has a first wall member is arranged facing the internal chamber of the casing in a first direction of the casing. The first wall member of the casing has a plurality of connector opening parts. At least two of the plurality of connector opening parts formed in the first wall member are arranged at different positions facing a different direction from each other.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, various embodiments of the present disclosure will be described with reference to the accompanying drawings. In the following description of the various embodiments, like reference characters or numerals designate like or equivalent component parts throughout the several diagrams.

An Exemplary Embodiment

It is desired for the present disclosure to provide the power converter having a high strength casing in which a plurality of connector opening parts are formed in a side wall of the casing.

A description will be given of a power convertor1according to an exemplary embodiment with reference toFIG.1toFIG.5.

FIG.1is a perspective view showing a structure of the power converter1according to the exemplary embodiment of the present disclosure.

The power converter1according to the exemplary embodiment has a casing2and a power converter circuit (not shown). The power converter circuit is arranged in an internal chamber of the casing2. That is, the casing2accommodates the power converter circuit.

As shown inFIG.1, a specific side wall (hereinafter, referred to as the first wall member20) in the side walls of the casing2is arranged facing the internal chamber of the casing2in a first direction. The specific side wall will also be referred to as the first wall member20. The first wall member20has a plurality of connector opening parts200. The number of the connector opening parts200is two in the structure of the power converter1according to the exemplary embodiment shown inFIG.1. Through the plurality of connector opening parts200, external connectors having a different shape are fitted with to being electrically connected to devices in the casing2. In particular, at least two connector opening parts in the plurality of connector opening parts200formed in the first wall member20are open facing respective different directions.

The power converter1according to the exemplary embodiment is an in-vehicle power converter, for example, to be mounted on hybrid vehicles (not shown), etc. The motor vehicle as a hybrid vehicle is driven by a dual front motor composed of a first front motor and a second front motor. Front wheels are arranged at a front compartment of the motor vehicle. The dual front motor is arranged in the transaxle arranged at the front compartment of the motor vehicle. Rear wheels of the motor vehicle are arranged at a rear side of the motor vehicle. The power converter1according to the exemplary embodiment is arranged over the transaxle arranged at the front compartment of the motor vehicle.

The power converter1according to the exemplary embodiment is equipped with a booster circuit, three inverters circuits, a DC-DC converter, etc. which are omitted from the drawings.

The booster circuit (not shown) boosts a battery voltage of a battery (not shown), and supplies the boosted battery voltage to three inverter circuits (not shown). Each of the three inverter circuits converts the boosted battery voltage to an alternating current power (AC power).

The three inverter circuits supply the converted AC power to respective three phase AC motors. In more detail, the three inverter circuits correspond to a first inverter circuit, a second inverter circuit and a third inverter circuit. The first inverter circuit supplies the respective AC power to the first front motor. The second inverter circuit supplies the AC power to the respective second front motor. The third inverter circuit supplies the respective AC power to the rear motor.

The DC-DC inverter circuit reduces the battery voltage of the battery, and supplies the reduced battery voltage to a low voltage battery. That is, the low voltage battery is changed by the reduced battery voltage. In the power converter1according to the exemplary embodiment, the casing2accommodates the booster circuit, the first to third inverters circuits, the DC-DC converter, etc.

FIG.2is a front view showing the structure of the power converter1according to the exemplary embodiment.FIG.3is a plan view showing the structure of the power converter1according to the exemplary embodiment.FIG.4is an exploded perspective view showing a structure of the casing2in the power converter1according to the exemplary embodiment.

As shown inFIG.1,FIG.2andFIG.4, the casing2has a rectangular box shape. The casing2is composed of a plurality of wall members. That is, the casing2is composed of a bottom wall member23, a first casing member21, a second casing member22and a ceiling wall member24which are stacked in order in a stacking Z direction.

In the stacking Z direction shown inFIG.4, the Z1side corresponds to the ceiling wall member24side viewed from the bottom wall member23side. The Z2side is opposite to the Z1side in the stacking direction Z.

As shown inFIG.4, when viewed from the stacking direction Z, a short side of the casing2corresponds to X direction. A longitudinal direction of the casing2corresponds to a Y direction.

As shown inFIG.1, the X direction is a facing direction through which the internal chamber of the casing2faces the first wall member20. The X1side is opposite to the X2side in the X direction.

As shown inFIG.1, the first wall member20is formed at the X1side in the X direction.

As shown inFIG.1andFIG.2, the Y1side is opposite to the Y2side in the Y direction. A first opening part is formed at the Y1side of the casing2. The first opening part will be explained later in detail. Similarly, a second opening part is formed at the Y2side of the casing2. The second opening part will be explained later in detail.

As shown inFIG.4, the X direction, the Y direction and the Z direction are orthogonal to each other.

As shown inFIG.4, the first casing member21and the second casing member22are arranged so that the internal chamber of the casing2is accommodated in the X direction and the Y direction by the first casing member21and the second casing member22. AlthoughFIG.4shows an outer frame of the first casing member21and an outer frame of the second casing member22. However, it is acceptable to arrange partition walls in the inside of the first casing member21and the second casing member22.

As shown inFIG.1,FIG.2andFIG.4, a bottom side opening part of the first casing member21arranged at the Z2side is covered with the bottom wall member23. An upper side opening part of the second casing member22arranged at the Z1side is covered with the ceiling wall member24.

The first casing member21is fixed to the bottom wall member23by screw members (for example, bolts and female screws, etc. not shown). Similarly, the second casing member22is fixed to the ceiling wall member24by screw members (for example, bolts and female screws, etc. not shown). Those screw members are omitted fromFIG.4.

As shown inFIG.4, the first casing member21has a first front wall211and a first rear wall212and a pair of first side walls213. The first front wall211faces the first rear wall212in the X direction. The pair of first side walls213face from each other in the Y direction. The first front wall211is arranged at the X1side of the first rear wall212. It is acceptable to arrange the power converter1at a desired location in the motor vehicle, and to rearrange those walls forming the first casing member21according to a structural requirement.

As shown inFIG.4, the second casing member22has a second front wall221and a second rear wall222and a pair of second side walls223. The second front wall221faces the second rear wall222in the X direction. The pair of second side walls223face from each other in the Y direction. The second front wall211is arranged at the X1side of the second rear wall222. It is acceptable to arrange the power converter1at a desired location in the motor vehicle and to rearrange those walls forming the second casing member22according to a structural requirement.

In the Z direction, the first front wall211and the second front wall221are located substantially at the same location, and the first rear wall212and the second rear wall222are located substantially at the same location. Similarly, the pair of first side walls213and the pair of second side walls223are arranged substantially at the same location. The second casing member22is fixed to the first casing member21by using bolts.

As shown inFIG.1, in the structure of the power converter1according to the exemplary embodiment, the first front wall211of the first casing member21and the second front wall221of the second casing member22form the first wall member20.

The two connector opening parts200are formed in the first wall member20. The two connector opening parts200are open facing respective different directions. Each of the connector opening parts200is a terminal formed in the casing2, and open toward a terminal of an external device to be connected to the power converter1. One of the two connector opening parts200has a first opening part201, and the other has a second opening part202.

As shown inFIG.1,FIG.2andFIG.4, the first opening part201is formed in the first casing member21, and the second opening part202is formed in the second opening part202. That is, the first opening part201and the second opening part202are formed in the different member, and the first opening part201and the second opening part202are open facing different directions from each other.

As shown inFIG.1,FIG.2andFIG.4, the first opening part201is formed in the first front wall211at the Y1side of the Y direction. The first opening part201penetrates the first front wall211in the X direction. The first opening part201is formed opening toward the X direction. The first opening part201substantially has a rectangular shape having a long side in the Y direction and a short side in the Z direction.

When the power converter1is mounted on a motor vehicle, the first wall member20as the specific side wall is arranged at one side in the direction which is intersected in the vertical direction, i.e. the Z direction, and the first opening part201is open facing the vertical direction.

As shown inFIG.1andFIG.4, a member arrangement part211ais formed at the Z1side on the surface of the first opening part201of the first front wall211so that the member arrangement part211aprojects toward the X2side in the X direction.

As shown inFIG.4, the member arrangement part211ahas a box shape opening in the X2side and the Z1side.

As shown inFIG.1toFIG.4, the second front wall221has a recessed part221awhich is recessed toward the X2side. The recessed part221ais recessed toward the X2side more than the surrounding parts of the recessed part221ain the second front wall221.

The recessed part221ais formed at the Y2side in the second front wall221. The area of the second front wall221at the Y1side of the recessed part221ais formed at the X2side more than the area at the Y2side of the recessed part221a. The recessed part221ais recessed toward the X2side more than the end part at the X1side of the first opening part201.

As shown inFIG.1,FIG.2andFIG.4, an opening formation part221bprojects toward the X1side from the end part at the Z2side of the recessed part221a. The opening formation part221bforms a part of the second front wall221.

The opening formation part221bis formed overlapped with the member arrangement part211ain the Z direction. The opening formation part221bhas a box shape opening toward the Z2side. An internal chamber of the opening formation part221bcommunicates with an internal chamber of the inside of the member arrangement part211a.

A part of a terminal module3is arranged in the internal chamber of the opening formation part221band the internal chamber of the recessed part211a. The terminal module3will be explained later.

As shown inFIG.1,FIG.3andFIG.4, the second opening part202is formed in the opening formation part221bso as to penetrate in the opening formation part221bat the Z1side. That is, as shown inFIG.4, the second opening part202is arranged opening in the Z direction.

When the power converter1is mounted on a motor vehicle, the second opening part202is arranged opening in the Z direction, i.e. toward the upper side in the vertical direction of the motor vehicle. The opening direction (i.e. the X direction) of the first opening part201is perpendicular to the opening direction (i.e. the Z direction) of the second opening part202from each other. The second opening part202substantially has a rectangle shape having a long side in the Y direction and a short side in the X direction.

As shown inFIG.1, the second opening part202is arranged at the Y2side more than the first opening part201. That is, the first opening part201and the second opening part202are arranged at a different location in the power converter1.

As shown inFIG.1,FIG.3andFIG.4, at least a part of the second opening part202is arranged inside of the recessed part221a. That is, at least a part of the second opening part202is arranged at the X2side more than the second front wall221excepting the recessed part221a.

FIG.5is a perspective view showing a structure of the terminal module3arranged in the power converter1according to the exemplary embodiment of the present disclosure.

As shown inFIG.1andFIG.5, the terminal module3is arranged in the internal chamber of the casing2. A plurality of terminals are formed in the terminal module3to be exposed outside through the first opening part201and the second opening part202. The terminals are assembled to the terminal module3as a monolithic member. It is possible to recognize the terminals of the terminal module3from the outside of the casing2.

As shown inFIG.5, the terminal module3is composed of a mold resin31and a plurality of bus bars32. The plurality of bus bars32are embedded in the mold resin31. The terminal module3has a monolithic structure formed by insert molding. That is, the insert molding feeds the mold resin31in the plurality of bus bars32arranged at predetermined intervals.

As shown inFIG.5, the plurality of bus bars32in the terminal module3are composed of a first bus bar321, a second bus bar322and a third bus bar323. The first inverter circuit supplies the AC power to the first front motor through the first bus bar321. The second inverter circuit supplies the AC power to the second front motor through the second bus bar322. Similarly, the third inverter circuit supplies the AC power to the third front motor through the third bus bar323.

As shown inFIG.5, the bus bars32in the terminal module3have respective inside terminals324a,324band324cand respective outside terminals325a,325band325c. The outside terminals325a,325band325care connected to output terminals of one or more semiconductor modules (not shown) forming the inverter circuit. Specifically, the inside terminal324aof the first bus bar321of the three phases is connected to the output terminal of the respective semiconductor module in the three phase semiconductor modules in the first inverter circuit. The inside terminal324bof the second bus bar322of the three phases is connected to the output terminal of the respective semiconductor module in the three phase semiconductor modules in the first inverter circuit. Similarly, the inside terminal324cof the third bus bar323of the three phases is connected to the output terminal of the respective semiconductor module in the three phase semiconductor modules in the first inverter circuit.

The output terminals of the semiconductor modules connected to the inside terminals324(324a,324band324c) are arranged straight in the Y direction. The inside terminals324and the output terminals of the semiconductor modules are connected in an arrangement (or a thickness) direction of the inside terminals324, i.e. in the Y direction.

As shown inFIG.1andFIG.2, the outside terminal325aof the first bus bar321and the outside terminal325bof the second bus bar322are exposed from the first opening part201. The outside terminal325cof the third bus bar323is exposed from the second opening part202.

A first connector (not shown) of a first wiring is fixed to the casing2. The transaxle is connected to the power converter1through the first connector of the first wiring. The terminals of the first connector are connected to the outside terminal325aof the first bus bar321, the outside terminal325bof the second bus bar322and the outside terminal325cof the third bus bar323.

As shown inFIG.1,FIG.2andFIG.4, a fixed part211b, projecting toward the X1side is formed in the outer periphery of the first opening part201. The first connector is fixed to a female screw formed in the fixed part211bin the X direction. That is, the first opening part201and the first connector fixed to the first opening part201are arranged in the X direction.

A second connector (not shown) of a second wiring is fixed to the casing2. The rear motor is connected to the power converter1through the second connector of the second wiring. The terminals of the second connector are connected to the outside terminal325cof the third bus bar323. The second connector is fixed in the Z direction to a female screw formed at both end parts in the Y direction of the second opening part202. That is, the second opening part202and the second connector fixed to the second opening part202are arranged in the Z direction. The second opening part202and the second connector are connected together in the Z direction.

The connection direction (i.e. the X direction) between the first opening part201and the first connector is orthogonal to the connection direction (i.e. Z direction) between the second opening part202and the second connector.

A description will be given of behavior and effects of the power converter1according to the exemplary embodiment.

In the structure of the power converter1according to the exemplary embodiment, at least two of the plurality of connector opening parts200formed in the specific side wall, i.e. the first wall member20are open facing a different direction. This improved structure makes it possible to prevent the area of the specific side wall as the first wall member20from being reduced in the X direction1side. This structure makes it possible to maintain a strength of the specific side wall as the first wall member20, and to maintain an overall strength of the casing2in the power converter1.

Further, in the structure of the power converter1according to the exemplary embodiment, the terminals formed in the terminal module3arranged in the internal chamber of the casing2are exposed outside from the plurality of connector opening parts. Those terminals are formed in the specific side wall as the first wall member20and open facing respective different directions. This improved structure makes it possible to reduce the number of components in the casing2and to reduce the overall size of the casing2because the plurality of connectors connected to the respective connector opening parts200are electrically connected to the terminal module3as a monolithic member arranged in the internal chamber of the casing2.

Further, the plurality of connector opening parts200, which are open facing a different direction, formed in the specific side wall as the first wall member20are formed in the different casing members, i.e. in the first casing member21, the second casing member22and the third casing member23. This makes it possible to reduce the overall area of those opening parts formed in the casing2and to increase the overall strength of the casing2.

In the structure of the power converter1according to the exemplary embodiment, the first opening part201is formed in the X direction as the facing direction to which the internal chamber of the casing2faces the specific side wall as the first wall member20, and the second opening part202is formed opening in a direction which is orthogonal to the X direction.

The specific side wall as the first wall member20has the recessed part221awhich is recessed to toward the internal chamber of the casing2in the X direction. Further, at least a part of the second opening part202is arranged inside of the recessed part221a. This structure prevents the second opening part202from projecting outside in the X direction, and allows the overall size of the casing3to be reduced.

When the power converter1according to the exemplary embodiment is mounted on a motor vehicle, the power converter1is arranged at the upper side of the transaxle of the motor vehicle. This arrangement allows the power converter1to be arranged on the front compartment of the motor vehicle after the power converter1is assembled with the transaxle through the first wiring.

After the power converter1is mounted on the motor vehicle, the specific side wall as the first wall member20is arranged at one side in the direction with which the specific side wall as the first wall member20is intersected, and the first opening part201is open toward this side. This arrangement makes it possible to easily reduce the length of the first wiring.

Further, after the power converter1is mounted on the motor vehicle, the second opening part202, which is open toward the upper side of the vertical direction, is connected to the second connector of the second wiring through which the power converter1is connected to the rear motor of the motor vehicle.

In general, because a rear motor is arranged at a location which is far from the location of a usual power converter, it becomes difficult to assemble the usual power converter and the rear motor together in a motor vehicle after the usual power converter is connected to the rear motor through the second wiring.

On the other hand, because the power converter1according to the exemplary embodiment has the improved structure in which the second opening part202is open toward the upper side, it is possible to easily connect the second connector of the second wiring to the second opening part202after the power converter1is arranged in the front compartment of the motor vehicle.

As previously described in detail, the present disclosure provides the power converter1in which the casing2has a string strength eve if the plurality of connector opening parts200are formed in the specific side wall, i.e. the first wall member20.

The concept of the present disclosure is not limited by the exemplary embodiment previously described. For example, it is acceptable to form additional opening in addition to the first opening part201and the second opening part202in the specific side wall as the first wall member20of the casing2. It is acceptable to form the additional opening which is open toward a different opening direction which is different from the opening direction of the first opening part201or the second opening part202, or toward the same opening direction of the first opening part201or the second opening part202.

It is acceptable to insert a tool into the connector opening parts so as to connect the power converter1with an external device by a bolt fastening.