JP5272405B2 - Car electrical equipment storage case - Google Patents

Description

  The present invention relates to an in-vehicle electric device housing case, and more particularly to a case for housing an in-vehicle electric device including a high voltage output unit that outputs a relatively high voltage and a low voltage output unit that outputs a relatively low voltage.

  In recent years, hybrid vehicles (Hybrid Vehicle (abbreviated as “HV”)) are becoming widespread in consideration of environmental impact, and electric vehicles and fuel cell vehicles are also being researched and developed for practical use.

  In a hybrid vehicle, an engine that is an internal combustion engine and a motor that is an electric motor are used in combination as a power source for driving drive wheels. The hybrid vehicle is equipped with an HV battery, which is a secondary battery capable of supplying a DC voltage of 288V, for example. The DC voltage supplied from the HV battery is boosted to 650 V, for example, by a boost converter, and then supplied to the inverter via a smoothing capacitor. The inverter converts the boosted DC voltage into a three-phase AC voltage and applies it to the three-phase synchronous AC motor. As a result, the motor is driven to rotate, and the driving force is transmitted to the drive wheels.

  On the other hand, a hybrid vehicle is also equipped with an auxiliary battery having a rated voltage of 12 V for supplying electric power to auxiliary devices such as lamps, audio, and various ECUs (Electronic Control Units). The auxiliary battery is maintained in a state in which a constant voltage can be output by charging the 288V DC voltage supplied from the HV battery by being stepped down to 12V by a DC / DC converter.

  In-vehicle electrical devices such as the above-described boost converter, inverter, and DC / DC converter may be housed together in a housing case and fixed to the vehicle body in an engine room where the engine is installed. When the engine compartment is located in the front of the vehicle and the on-board electrical equipment storage case is fixed at a relatively forward position in the engine compartment (for example, immediately behind the radiator), Due to the deformation, for example, a metal housing case may be damaged, and an in-vehicle electric device housed inside may be damaged or exposed to the outside.

  For example, in Patent Document 1, a cover corresponding to the in-vehicle electric device housing case is indirectly fixed to a vehicle body via a fixing member or a supporting member, so that an impact force received at the time of a vehicle collision is also distributed to the supporting member. It is described that the external force applied to the cover through the fixing member can be reduced by doing so, and as a result, the power conversion device stored in the cover can be prevented from being damaged.

JP 2006-262673 A

  However, from the viewpoint of reducing the number of parts, it is desirable to directly attach the in-vehicle electric device housing case to the vehicle body without using a fixing member or a support member. In this case, since the impact load at the time of the vehicle collision is directly transmitted from the vehicle main body to the in-vehicle electric device housing case, how to suppress or prevent the deformation or breakage of the in-vehicle electric device housing case is a problem. It becomes.

  Here, there is an in-vehicle electric equipment housing case 60 as shown in FIG. The in-vehicle electric device housing case 60 is configured as a closed housing by fastening the upper case 64 and the lower case 66 with bolts (not shown) with the intermediate plate 62 sandwiched therebetween. Inside the case, in-vehicle electric devices such as an inverter, a step-up / down converter, and a step-down converter fixed to the upper and lower surfaces of the middle plate 62 are stored.

  Each of the upper case 64 and the lower case 66 can be integrally formed by aluminum die casting. A substantially earlobe mounting portion 70 having a bolt insertion hole 68 is integrally formed at the lower portion of the side surface of the upper case 64 at the rear of the vehicle so as to protrude toward the rear of the vehicle. Similarly, a mounting portion is integrally formed on the lower portion of the upper case 64 at the front side of the vehicle, but is not shown in FIG.

  A substantially semi-cylindrical boss portion 72 bulges integrally with the lower case 66 on the side surface of the lower case 66 on the rear side of the vehicle, corresponding to the mounting portion 70 of the upper case 64. A female screw hole extending in the vertical direction is formed inside the boss portion 72. In addition, a substantially earlobe-shaped fixing portion 76 having a bolt insertion hole 74 is formed on the side surface of the lower case 66 on the vehicle rear side so as to project integrally with the lower case 66 toward the vehicle rear side. The lower part of the part 72 is connected. Similarly, on the left and right side surfaces of the lower case 66, a substantially earlobe-shaped fixing portion 80 having bolt insertion holes 78 is formed so as to project integrally with the lower case 66 (only one is shown in FIG. 6). As a result, the in-vehicle electric device housing case 60 is fixed to the vehicle main body with the bolts at the three locations of the fixing portion 76 on the vehicle rear side and the two fixing portions 80 and 80 on the left and right sides of the vehicle.

  In such an in-vehicle electric device housing case 60, when it is attached to the front side in the engine room in the front part of the vehicle (for example, immediately behind the radiator), it is large as indicated by the arrow 82 due to the front part collision of the vehicle. Impact load acts. As a result, an impact load acts on the in-vehicle electric device housing case 60 from the vehicle body through the rear fixing portion 76 among the three fixing portions 76, 80, 80.

  At this time, the rear fixing portion 76 is formed to be connected to the lower portion of the boss portion 72, and the boss portion 72 is thicker and more rigid than the other portions of the lower case 66. In addition, the impact load transmitted through the fixing portion 76 is transmitted to the upper case 64 through the boss portion 72 that is a high-rigidity portion and the mounting portion 70 that is bolted thereto. As a result, the upper case Deformation or breakage 84 may occur on the rear side surface 65 of 64 around the mounting portion 70. In that case, if an inverter that processes or outputs a high voltage is accommodated in the upper case 64, the inverter may be damaged or exposed to the outside.

  Accordingly, an object of the present invention is to provide an in-vehicle electric device that can prevent damage to the high-voltage output device and external exposure even if the case is deformed or damaged by applying an impact load at the time of a vehicle collision (hereinafter referred to as “collision load”). It is to provide a storage case.

An in-vehicle electric equipment housing case according to the present invention is supplied from a battery and an inverter that converts a DC voltage after boosting a DC voltage supplied from the battery by a boost converter into an AC voltage and outputs a relatively high voltage. A case for housing an in-vehicle electric device including a step-down converter that steps down a DC voltage and outputs a relatively low voltage, and is fixed to the housing case so as to be integrally molded on the outer surface of the case wall. The step-down converter is disposed inside the case at a position corresponding to the fixed portion, and the case wall portion includes a high-rigidity portion that is higher in rigidity than other portions of the case, The rigid portions are respectively provided on both sides of the fixed portion with a predetermined distance from the fixed portion .

According to the in-vehicle electrical equipment storage case with this configuration, even if a collision load is applied to the case via the fixing part fixed to the vehicle body and the case wall part around the fixing part is deformed or damaged, this fixing part can be handled. Since the step-down converter, which is a low voltage output part of the in- vehicle electric device, is disposed inside the case at the position where it is placed, damage to the inverter , which is the high voltage output part , and external exposure can be prevented.

In addition, according to the on-vehicle electric device housing case having this configuration, since the fixing portion is provided separately from the high-rigidity portion of the case wall portion, the collision load applied to the case via the fixing portion passes through the high-rigidity portion. By suppressing transmission to the other part of the case having relatively low strength, it is possible to prevent the case wall part covering the high voltage output part from being deformed or damaged. Furthermore, Runode have high rigidity portion are provided on both sides of the fixing portion, even deformation and damage of the case wall portion is generated by the collision load applied to the case through the fixing unit, the high range of the deformation It can be limited to the area between the rigid parts.

  In the on-vehicle electric device housing case according to the present invention, the fixing portion may be provided with a weakening portion whose strength against impact is weakened.

  According to the on-vehicle electric device housing case with this configuration, the fixed portion is easily broken at the weakened portion by the collision load, so that the transmission of the collision load to the case wall portion can be reduced, and the deformation of the case wall portion can be reduced. Breakage can be suppressed or prevented.

  Further, in the on-vehicle electric device housing case according to the present invention, the fixing portion may be provided so as to protrude toward the rear of the vehicle.

  According to the in-vehicle electrical device housing case of this configuration, it is possible to more effectively suppress the in-vehicle electrical device housing case from moving toward the vehicle rear side when a collision load from the front of the vehicle is applied, and in the vicinity of the rear of the case This is advantageous in preventing deformation or breakage of the case due to contact with another structure disposed in the housing.

  Moreover, in the vehicle-mounted electrical equipment accommodation case according to the present invention, it may be disposed near the front of the vehicle in the engine room of the vehicle.

According to the on-vehicle electric device housing case having this configuration, even if a collision load due to a collision at the front of the vehicle is applied to the case, it is possible to prevent damage to the inverter that is the high-voltage output unit and external exposure.

According to the on-vehicle electric device housing case according to the present invention, even if the case is deformed or damaged due to a collision load , the inverter which is a high voltage output unit in the on-vehicle electric device can be prevented from being damaged and exposed to the outside.

  Embodiments according to the present invention will be described below in detail with reference to the accompanying drawings. In this description, specific shapes, materials, directions, numerical values, and the like are examples for facilitating the understanding of the present invention, and can be appropriately changed according to the application, purpose, specifications, and the like.

  FIG. 1 shows a configuration of a hybrid vehicle 1 equipped with a PCU housing case 10 that houses a power control unit (Power Control Unit, abbreviated as “PCU”), which is an embodiment of a vehicle electrical device housing case according to the present invention. FIG. The hybrid vehicle 1 includes a four-cylinder engine 14 that is an internal combustion engine and a motor generator 16 that is an electric motor as power sources for driving the front wheels 12R and 12L that are drive wheels. The hybrid vehicle 1 also includes a motor generator 18 as a generator that generates electric power by using the rotation of the front wheels 12R and 12L when the vehicle is decelerated or braked.

  The engine 14 and the two motor generators 16 and 18 are mounted in the engine room or the engine compartment 2 at the front of the vehicle. The driving force by the engine 14 is transmitted to the front wheel axle 24 via the power split mechanism 20 and the speed reducer 22. The driving force generated by the motor generator 16 is transmitted to the front wheel axle 24 via the speed reducer 22.

  The PCU housing case 10 is disposed at a position relatively to the left of the front in the engine room 2 and immediately behind the radiator 26, and is fixed to the vehicle body as will be described later. The PCU in the PCU housing case 10 is composed of in-vehicle electric devices such as an inverter including a plurality of switch elements, a step-up / down converter including a reactor, and a step-down converter including a switching element and a transformer. To the motor generators 16 and 18, respectively.

  An HV battery 30 capable of outputting a DC voltage of 288 V, for example, is mounted between positions substantially corresponding to the rear wheels 28R and 28L at the rear of the vehicle, more specifically between the rear seat (not shown) and the rear trunk room 3. Has been. The HV battery 30 is composed of a secondary battery such as a nickel metal hydride battery or a lithium ion battery, and is connected to the PCU in the PCU housing case 10 via a power line.

  An auxiliary battery 32 is also mounted in the engine room 2. The auxiliary battery 32 can be composed of a lead secondary battery with a rated voltage of 12 V for general vehicle use. The auxiliary battery 32 supplies electric power necessary for operating on-vehicle auxiliary equipment 34 (see FIG. 2) such as a lamp, audio, and various ECUs. The auxiliary battery 32 is also connected to the PCU in the housing case 10 via the power line.

  Next, the operation of the hybrid vehicle 1 will be briefly described with reference to FIG. In FIG. 2, the PCU stored in the PCU housing case 10 includes a step-up / down converter 40, a smoothing capacitor 42, a first inverter 44, a second inverter 46, and a step-down converter 48, and the hatching portion is The power transmission system is shown.

  The driving force, that is, the rotation generated by the engine 14 is transmitted to the axle 24 through the power split mechanism 20 and the speed reducer 22, whereby the front wheels 12R and 12L are driven to rotate and the vehicle travels.

  In the hybrid vehicle 1, the driving force generated by the motor generator 16, that is, the rotation, is transmitted to the axle 24 via the speed reducer 22 in a region where the engine efficiency is deteriorated such as when starting or running at a low speed. To do. Specifically, a 288 V DC voltage supplied from the HV battery 30 is boosted to the upper limit value of about 650 V by the step-up / down inverter 40 and then supplied to the first inverter 44 via the smoothing capacitor 42. The first inverter 44 converts the boosted DC voltage into a three-phase AC voltage and applies it to the motor generator 18, whereby the motor generator 18 is rotationally driven.

  Note that when the vehicle is in a high load state such as sudden acceleration or a steep slope, driving by both the engine 14 and the motor generator 16 may be used together.

  On the other hand, when the vehicle is decelerated or braked, the rotation of the front wheels 12R and 12L is transmitted to the motor generator 18 via the speed reducer 22 to generate power. The AC voltage generated by the motor generator 18 is converted into a DC voltage by the second inverter 46 and then supplied to the step-up / down converter 40 via the smoothing capacitor 42. In the step-up / step-down inverter 40, the DC voltage supplied from the second inverter 46 is stepped down to a predetermined voltage value, and the HV battery 30 is charged. Thereby, the HV battery 30 is maintained in a state capable of outputting a constant voltage.

  The motor generator 18 is not only used as a generator, but can also be used as a cell motor when starting the engine.

  Further, the 288 V DC voltage supplied from the HV battery 30 is also used for charging the auxiliary battery 34. That is, the DC voltage supplied from the HV battery 30 is stepped down to a predetermined voltage value by the step-down converter 48, and then charged to the auxiliary battery 32 through the smoothing capacitor 50, whereby the auxiliary battery 32 has a constant voltage. The output is maintained.

  Next, the PCU housing case 10 will be described with reference to FIGS. 3 and 4 (partial sectional view taken along line AA in FIG. 3). Here, the PCU housing case 10 has a similar configuration to the conventionally known in-vehicle electrical device housing case 60 described with reference to FIG. 6, and therefore the same or similar components are denoted by the same or similar reference numerals. Is attached.

  The PCU housing case 10 is formed by fastening an upper case 64 and a lower case 66 with bolts 52 via two spring washers 54 and a ring washer 56 with an intermediate plate 62 made of a metal plate such as aluminum interposed therebetween. Configured as a closed enclosure. The two washers 54 and 56 substantially correspond to the thickness of the intermediate plate 62, but may be replaced by a single spacer member or a protrusion formed at the edge of the intermediate plate 62.

  Inside the case, there are first and second inverters 44 and 46 fixed to one surface or upper surface 62a of the intermediate plate 62 via an insulating layer (not shown), and an insulating layer (not shown) on the other side or lower surface 62b. The step-up / step-down converter 40 and the step-down converter 48 that are fixed via the terminal are stored. Here, the step-down converter 48 is located on the vehicle rear side (left side in FIG. 4) with respect to the step-up / down converter 40 and is disposed inside the case at a position corresponding to a fixing portion 76 described later.

  Here, as described above, the step-down converter 48 outputs a DC voltage of about 12 V for charging the auxiliary battery. On the other hand, the buck-boost converter 40 boosts and outputs the DC voltage supplied from the HV battery 30 to an upper limit value of about 650 V. The first inverter 44 or the second inverter 46 boosts the voltage by the buck-boost converter 40. The converted DC voltage is converted into a three-phase AC voltage, or the inverse conversion is executed. Therefore, in this embodiment, the step-down converter 48 corresponds to a low voltage output unit that outputs a relatively low voltage, and the first and second inverters 44 and 46 and the step-up / down converter 40 output a relatively high voltage. It corresponds to the voltage output unit.

  Each of the upper case 64 and the lower case 66 can be integrally formed by aluminum die casting. Two substantially earlobe-shaped attachment portions 70a and 70b each having a bolt insertion hole 68 are protruded toward the vehicle rear side at a predetermined interval in the left-right direction or the horizontal direction at the lower part of the side surface of the upper case 64 at the rear side of the vehicle. Is formed. Similarly, at least one mounting portion is integrally formed at the lower portion of the side surface of the upper case 64 in front of the vehicle, but is not shown in FIG.

  Two substantially semi-cylindrical boss portions 72a and 72b are provided on the side surface 67 of the lower case 66 on the vehicle rear side at predetermined intervals in the left-right direction or the lateral direction, corresponding to the attachment portions 70a and 70b of the upper case 64. The lower case 66 is bulged and formed integrally. Internal thread holes 73 extending in the vertical direction are formed in the boss portions 72a and 72b, respectively. Since the boss portions 72a and 72b are formed to be thicker than other portions of the side wall 67 of the lower case 66, the boss portions 72a and 72b are higher in rigidity than the other portions.

  Further, a substantially earlobe-shaped fixing portion 76 having a bolt insertion hole 74 is formed on the side surface 67 of the lower case 66 on the vehicle rear side so as to protrude integrally with the lower case 66 toward the vehicle rear side. The fixing portion 76 is formed at the laterally central portion of the side surface 67, and the boss portions 72a and 72b are provided on both sides of the fixing portion 76 with a predetermined distance d therebetween. As described above, since the fixing portion 76 is provided not on the vehicle front side of the PCU housing case 10 but on the vehicle rear side, the PCU housing case 10 moves toward the vehicle rear side when a collision load from the vehicle front is applied. This is more effective in preventing deformation and breakage of the case due to contact with another hard structure (for example, a brake master cylinder) disposed in the vicinity of the rear of the case.

  Similarly, on the left and right side surfaces of the lower case 66, substantially earlobe-shaped fixing portions 80 having bolt insertion holes 78 are respectively formed integrally with the lower case 66 (only one is shown in FIG. 3). As a result, the PCU housing case 10 is fixed to the vehicle main body with the bolts at the three locations of the fixing portion 76 on the vehicle rear side and the two fixing portions 80 and 80 on the left and right sides of the vehicle.

  Since this PCU housing case 10 is attached to the front side in the engine room 2 in the front part of the vehicle, a large collision load as shown by an arrow 82 acts by a frontal collision of the vehicle. As a result, a collision load acts on the PCU housing case 10 from the vehicle body via the rear fixing portion 76 among the three fixing portions 76, 80, 80.

  At this time, since the rear fixing portion 76 is formed at a predetermined distance d from the boss portions 72a and 72b, the collision load transmitted through the fixing portion 76 is a high-rigidity boss portion 72a and 72b. In addition, transmission to the upper case 64 via the mounting portions 70a and 70b fastened to the bolts can be reduced or suppressed. As a result, the inverters 44 and 46 which are high voltage output portions are covered. It is possible to prevent the wall portion 65 of the upper case 64 from being deformed or damaged.

  Further, even if the wall portion 67 of the lower case 66 around the fixing portion 76 is deformed or damaged in the region indicated by reference numeral 86 in FIG. 3 due to the collision load, the inner side of the case at the position corresponding to the fixing portion 76 Since the step-down converter 48 which is a low voltage output unit is disposed, the first and second inverters 44 and 46 and the step-up / down converter 40 which are high voltage output units can be prevented from being damaged and exposed to the outside.

  Further, since the boss portions 72a and 72b, which are high rigidity portions, are provided on both sides of the fixing portion 76, the case wall portion 67 is deformed or damaged by a collision load applied to the lower case 66 through the fixing portion 76. Even if this occurs, the range of deformation or the like can be limited to the region 86 between the boss portions 72a and 72b.

  In the PCU housing case 10, the boss portions 72a and 72b are described as being highly rigid portions. However, the present invention is not limited to this, and for example, to increase the wall strength of the lower case 66. The present invention can also be applied when the reinforcing ribs and the like are high-rigidity portions.

  Next, a PCU housing case 11 which is another embodiment of the present invention will be described with reference to FIG. Since this PCU housing case 11 has substantially the same configuration as the in-vehicle electrical device housing case 60 described above with reference to FIG. 6, the same components are denoted by the same reference numerals, and the description thereof is incorporated. Only the differences will be described here.

  In the PCU housing case 11, a groove-shaped weakened portion 88 is formed along the outer shape of the boss portion 72 in the lower case 66 in the vicinity of the base of the fixing portion 76 that is a connecting portion with the boss portion 72. The weakened portion 88 slightly reduces the thickness of the base portion of the fixing portion 76, thereby slightly reducing the strength. Accordingly, the fixed portion 76 is easily broken at the weakened portion 88 by the collision load 82, and a part or most of the collision load is absorbed by the destruction. As a result, the transmission of the collision load to the wall portion of the PCU housing case 11 can be reduced, and deformation or breakage of the case wall portion can be suppressed or prevented.

  In the present embodiment, the weakening portion 88 is formed as a groove, but any configuration or shape that can weaken the strength may be used. For example, one or a plurality of through-holes near the base of the fixing portion 76 May be formed.

  By the way, although the example which mounts a PCU accommodation case in a hybrid vehicle was demonstrated in the above, the vehicle-mounted electric equipment accommodation case which concerns on this invention is not restricted to a hybrid vehicle, Other electric vehicles, such as an electric vehicle and a fuel cell vehicle Can also be installed.

It is a schematic block diagram of the hybrid vehicle carrying the PCU accommodation case which is one Embodiment of this invention. It is a functional block diagram of a hybrid car showing in-vehicle electric equipment stored in a PCU accommodation case. It is a perspective view which shows a PCU accommodation case. FIG. 4 is a partial cross-sectional view taken along line AA of the PCU housing case of FIG. 3. It is a perspective view which shows the PCU accommodation case which concerns on another embodiment. It is a perspective view which shows an example of the conventional vehicle-mounted electrical equipment accommodation case.

Explanation of symbols

  1 hybrid vehicle, 2 engine room or engine compartment, 3 rear trunk room, 10, 11 PCU housing case, 12R, 12L front wheel, 14 engine, 16, 18 motor generator, 20 power split mechanism, 22 speed reducer, 24 front wheel axle, 26 Radiator, 28R, 28L Rear wheel, 30 HV battery, 32 Auxiliary battery, 34 In-vehicle auxiliary equipment, 40 Buck-boost converter, 42 Smoothing capacitor, 44 First inverter, 46 Second inverter, 48 Step-down converter, 52 volts, 54 Spring washer, 56 Ring washer, 60 On-board electrical equipment housing case, 62 Middle plate, 64 Upper case, 65 Rear side or wall, 66 Lower case, 67 Side, side wall or wall, 68 Bolt insertion hole, 70, 70a , 7 b mounting portion, 72, 72a, 72b boss portion 74 bolt insertion holes, 76 fixing unit, 78 bolt insertion holes, 80 fixing unit, 88 weakened portion.

Claims (4)

An inverter that boosts the DC voltage supplied from the battery with a boost converter, converts the DC voltage to an AC voltage and outputs a relatively high voltage, and steps down the DC voltage supplied from the battery to reduce the relatively low voltage. A case for housing an in-vehicle electric device including a step-down converter for output,
A fixing portion that is integrally molded on the outer surface of the case wall portion and fixes the housing case to the vehicle body; and the step-down converter is disposed inside the case at a position corresponding to the fixing portion, and the case wall portion Has a high-rigidity part having higher rigidity than other parts of itself, and the high-rigidity part is provided on both sides of the fixing part with a predetermined distance from the fixing part. In-vehicle electrical equipment storage case. In the on-vehicle electric device storage case according to claim 1 ,
The in-vehicle electric device housing case, wherein the fixing portion is provided with a weakening portion weakened in strength against impact. In the on-vehicle electric device storage case according to claim 1 or 2 ,
The in-vehicle electric equipment housing case, wherein the fixing portion is projected toward the rear of the vehicle. In the in-vehicle electric equipment storage case according to any one of claims 1 to 3 ,
An in-vehicle electric device housing case, which is disposed near the front of a vehicle in an engine room of the vehicle.

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