JP4547986B2 - Electronic unit, vehicle drive device, and vehicle - Google Patents

Description

  The present invention relates to an electronic unit, and more particularly to an electronic unit that houses electronic components and electronic circuits therein.

Japanese Unexamined Patent Publication No. 2003-338423 (Patent Document 1) discloses a capacitor in which capacitor elements are arranged in a capacitor case and filled with an epoxy resin or the like. This capacitor is used for voltage smoothing of an inverter circuit that drives an automobile motor.
JP 2003-338423 A JP 2003-338424 A JP 2003-338425 A

  A smoothing capacitor for an inverter circuit that drives an automobile motor has a plurality of capacitor elements connected in parallel by a metal bus bar to satisfy the demand for high frequency, high current and large capacity, and a part of the metal bus bar is electrically connected to the outside. The capacitor unit is provided as a terminal for connection. Such a capacitor unit and an inverter circuit are heavy, and there is a case where the positioning of the terminal portion is shifted when the capacitor unit is attached to the inverter side, and there is a problem that the efficiency of assembly is not good.

  An object of the present invention is to provide an electronic unit with improved production efficiency during assembly.

  In summary, the present invention is an electronic unit, which is a first case having a first side wall, a second case having a second side wall that is fitted inside the first side wall, and a second case. The electronic component housed inside the case and the first terminal portion connected to the electronic component are fixed with the relative position of the second side wall fixed. In the state of being overlapped, at least a part of the second side wall protrudes from the first side wall.

  Preferably, the first case further includes a first bottom part having a peripheral edge connected to the first side wall, and the second case has a peripheral part connected to the second side wall and overlapped with the first bottom part. The electronic unit further includes a filling portion that fills the second case and fixes the position of the electronic component and the first terminal portion.

  More preferably, the first case is made of metal, the second case is made of an insulating resin, and the filling portion is made of an insulating resin.

  Preferably, the electronic component includes a plurality of capacitors each having a first electrode and a second electrode, and the first terminal portion is a first terminal to which the first electrodes of the plurality of capacitors are connected in common. And a second terminal to which the second electrodes of the plurality of capacitors are connected in common.

Preferably, a flange portion is formed on the first side wall, and the electronic unit is disposed so as to cover the opening of the first case, and has a structure housing an electric circuit electrically connected to the electronic component. Further, the structure includes a third side wall, a second side wall, and a first terminal part, wherein a flange part that contacts the flange part of the first side wall is formed, and the third side wall is disposed outside the second side wall. And a second terminal portion that is electrically connected to the electric circuit.

  More preferably, the first terminal portion includes a first plate terminal provided with a first hole, and the second terminal portion includes a second plate terminal provided with a second hole. The electronic unit further includes a screw that connects the first and second plate terminals using the first and second holes.

  More preferably, the electric circuit includes a boosting unit that boosts the voltage of the battery, and an inverter that receives the output of the boosting unit and drives the motor, and the electronic component includes a capacitor that stabilizes the output voltage of the boosting unit. .

  According to the present invention, the mounting position of the structural body with respect to the first case is positioned by the protruding portion of the side wall of the second case disposed inside the first case, so that the efficiency of assembling the electronic unit is improved. To do. Further, since the position of the terminal portion is also determined by this, the terminal portion is not displaced and the production efficiency is improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

  FIG. 1 is a schematic circuit diagram for explaining a motor drive system of a vehicle in which the electronic unit of the present invention is used. This vehicle corresponds to, for example, an electric vehicle, a hybrid vehicle that uses an engine that is an internal combustion engine, an electric motor, and a power source.

  Referring to FIG. 1, this vehicle is connected between battery 2, booster circuit 4 that boosts the output voltage of battery 2 and outputs the boosted voltage between nodes N1 and N2, and output nodes N1 and N2 of booster circuit 4. A capacitor unit 6 that stabilizes the output voltage and an inverter 8 that receives the output of the booster circuit 4 stabilized by the capacitor unit 6 as a power source and drives the AC motor 10 are included.

  Although not shown, AC motor 10 includes three-phase coils of U, V, and W. Although not shown, inverter 8 includes a U-phase arm, a V-phase arm, and a W-phase arm that control the current flowing through the coil of motor 10, and each arm is connected in series between nodes N 1 and N 2. Two switching elements are included. The inverter 8 is an intelligent power module, and includes an electronic circuit that controls driving of each switching element and controls overcurrent protection.

  The booster circuit 4 includes a coil 12 having one end connected to the positive electrode of the battery 2, an IGBT (insulated gate bipolar transistor) element 14 connected between the other end of the coil 12 and the node N <b> 1, IGBT element 16 connected between the other end and node N2 is included. Note that the negative electrode of the battery 2 is connected to the node N2.

  FIG. 2 is a plan view of the capacitor unit 6 of FIG.

  FIG. 3 is a cross-sectional view taken along line III-III of the capacitor unit 6 of FIG.

  4 is a cross-sectional view taken along IV-IV of the capacitor unit 6 of FIG.

  2 to 4, the capacitor unit 6 includes a metal case 22, a resin case 24 accommodated inside the case 22, and a plurality of capacitor elements 30 disposed inside the resin case 24. And plate-like terminals 26 and 28 electrically connected to the plurality of capacitor elements 30.

  Capacitor element 30 is, for example, a film capacitor with high pressure resistance. Capacitor element 30 is connected in parallel between two bus bars (not shown). The plate-like terminals 26 and 28 are a part of these two bus bars.

  The metal case 22 is made of, for example, aluminum die casting that can be mass-produced. The metal case 22 protects the internal capacitor element from external impacts and the like. Further, when combined with the inverter 8 and the booster circuit 4, it also has an effect as a shield for preventing electromagnetic noise generated from the booster circuit 4 and the inverter 8 from leaking to the outside.

  The resin case 24 is made of a resin having good insulation and moisture resistance, ensures insulation between the metal case 22 disposed outside the resin case 24 and the internal capacitor element 30, and prevents the capacitor element 30 from moisture. Used to protect. Further, in order to further secure the moisture resistance of the capacitor element 30, the resin case 24 is filled with an epoxy resin or the like.

  The terminals 26 and 28 protrude upward from the resin portion 25 filled in the resin case 24, and a bolt mounting hole is provided at each tip portion.

  A flange portion 23 is formed on the upper side wall of the metal case 22. The upper end of the side wall of the resin case 24 protrudes further upward from the flange portion 23. Since the upper end of the side wall of the resin case 24 is integrated with the flange portion 23 to form a so-called inlay structure, the assembly efficiency is improved.

  FIG. 5 is a view for explaining a state in which the entire electronic unit of the present invention is assembled.

  Referring to FIG. 5, structure 40 that accommodates the inverter and the booster is arranged so as to cover the opening of metal case 22. The structure 40 includes a side wall 45 in which a flange portion 41 that abuts on the flange portion 23 of the metal case 22 is formed. A hole 50 is provided in a part of the side wall 44 facing the side wall 45.

  The upper end of the resin case 24 projects upward from the flange portion 23. The flange portion 41 can be easily positioned by covering the structure 40 from above along the protruding portion of the resin case 24. Although not shown, a sealing agent such as FIPG (Formed In Place Gasket) for waterproofing is sandwiched between the flange portion 23 and the flange portion 41. FIPG may also be called a liquid gasket.

  In the present invention, since the protruding portion is provided by the resin case 24, even if the flange portion 41 hits the protruding portion when the heavy structure 40 is covered, the flange portion 41 contacts the surface to be joined. Hard to scratch. Therefore, if the structure 40 is covered normally after that, the waterproof performance by a sealing agent can be maintained favorable.

  The structure 40 includes a plate-like terminal 46 that is electrically connected to the inverter and the booster. A bolt insertion hole is provided at the tip of the terminal 46, and an internal thread is cut in this hole. The bolts 52 are inserted from the holes 50 and the terminals 26 and 46 are fastened. The hole 50 is closed after the bolt 52 is fastened to ensure waterproofness.

  FIG. 6 is a study example for explaining a problem when the height of the resin case is the same as that of the flange portion.

  Referring to FIG. 6, if the height of the upper end of the side wall of resin case 124 arranged inside metal case 122 is the same as or lower than flange portion 123, when the structure is arranged from above. Positioning is difficult.

  First, it is difficult to match all the periphery of the flange portion 123 and the flange portion 141 to the butted state. Further, even if the flanges 123 and 141 are intended to be combined, it is considered that the positions of the bolt holes provided in the plate terminals 126 and 128 and the bolt holes of the plate terminals 146 and 148 provided on the structure side are shifted. It is done.

  Intelligent power modules and capacitors for on-vehicle motor control are heavy and require a lot of force to perform fine alignment, resulting in poor productivity. When the terminal is displaced, the position of such a member having a certain weight must be finely adjusted. If too much force is applied for fine adjustment, the terminal is displaced in the opposite direction.

  Therefore, in the examination example shown in FIG. 6, the positions of the bolt holes provided in the plate-like terminals 126 and 128 connected to the capacitor element 130 and the bolt holes of the plate-like terminals 146 and 148 provided on the structure side. It becomes difficult to match.

  FIG. 7 is a view for explaining good productivity of the electronic unit of the present invention.

  Referring to FIGS. 5 and 7, the electronic unit is required to be downsized, and the entire width W1 needs to be kept small. On the other hand, the larger the volume of the capacitor, the larger the capacity can be secured. In order to secure the necessary capacity, the width W2 inside the resin case 24 that accommodates the capacitor cannot be made too small.

  Further, the width W3 of the flange portion in FIG. 7 is sandwiched with a liquid gasket to protect electronic devices such as capacitors, inverters and boosters housed in the case from moisture. In order to obtain the sealing effect of the liquid gasket, it is necessary to secure a width W3 of a certain value or more (for example, about 5 mm). Although not shown, the flange portions 23 and 41 are provided with bolt holes for fastening the case 22 and the structural body 40. For this reason as well, the width of the flange portion cannot be made very narrow.

  Accordingly, it is not desirable to provide a protrusion for positioning on the case 22 because the width W3 of the flange portion becomes wide and as a result the overall width W1 becomes large.

  As shown in FIG. 7, in the present invention, the upper end of the side wall of the resin case 24 is made higher than the flange portion 23 of the case 22, and the side wall flange is formed along the side wall of the structure along the upper end of the resin case 24. By aligning the portion 41 and the flange portion 23 of the case 22 with the mating surface S, the positioning is good.

  Preferably, the thickness of the resin case rises so that the outer surface of the resin case protrudes from the flange portion 23 toward the inner side rather than the vertical direction so that the structure 40 can be easily put on the capacitor unit 6. It is desirable to be thin.

  Further, as shown in FIG. 5, the positional relationship between the terminals 46 and the side walls 44 and 45 is also fixed on the structure 40 side. The relative positional relationship between the plate-like terminal 46 and the side walls 44 and 45 is determined according to the relative positional relationship between the side wall of the resin case 24 and the plate-like terminal 26. When the structure 40 is covered along the resin case 24, the terminal 46 is naturally installed at a suitable position so that the terminal 46 is connected to the terminal 26 by the bolt 52. Therefore, it becomes easy to connect the bolt 52 from the hole 50. Although not shown in FIG. 5, the terminal 28 and the terminal 48 in FIG. 7 are also naturally installed at suitable positions and can be easily fastened with bolts.

  As described above, in the embodiment of the present invention, the bolt holes of the plate terminals 26 and 28 connected to the capacitor element 30 and the bolt holes of the plate terminals 46 and 48 provided on the structure 40 side. As a result, the assembly productivity of the electronic unit can be improved.

  Further, in the present invention, since the protruding portion is provided by the resin case 24, even if the flange portion 41 hits the protruding portion when the heavy structural body 40 is covered, the flange portion 41 is joined. It is difficult to scratch the surface. Therefore, if the structure 40 is covered normally after that, the waterproof performance by a sealing agent can be maintained favorable.

  Furthermore, by providing a protruding portion with the inner resin case 24 to form an inlay structure, even if a conductive foreign substance enters from the flange gap, it is not necessary to short-circuit with the internal electronic components.

  In the present embodiment, the case where the upper end portion of the side wall of the resin case 24 is entirely higher than the flange portion 23 of the metal case 22 is shown as an example. However, for example, only a part of the side wall of the resin case 24 is used. Even if the height is higher than that of the flange portion 23, the same effect can be obtained.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic circuit diagram for demonstrating the motor drive system of the vehicle in which the electronic unit of this invention is used. It is a top view of the capacitor | condenser unit 6 of FIG. It is sectional drawing in III-III of the capacitor | condenser unit 6 of FIG. It is sectional drawing in IV-IV of the capacitor | condenser unit 6 of FIG. It is a figure for demonstrating the state which assembled the whole electronic unit of this invention. It is an examination example for demonstrating a problem in case the height of a resin case is the same as a flange part. It is a figure for demonstrating the favorable productivity of the electronic unit of this invention.

Explanation of symbols

  2 Battery, 4 Booster circuit, 6 Capacitor unit, 8 Inverter, 10 Motor, 12 Coil, 14, 16 IGBT element, 22, 122 Case, 23, 41, 123, 141 Flange part, 24, 124 Resin case, 25 Resin part 26, 28, 46, 48, 126, 128, 146, 148 terminals, 30, 130 capacitor elements, 40 structures, 44, 45 sidewalls, 50 holes, 52 volts.

Claims (14)

A first case having a first sidewall;
A second case having a second side wall that fits over the inside of the first side wall;
An electronic component housed inside the second case;
A first terminal portion fixed in a relative position to the second side wall and connected to the electronic component ;
A structure that houses an electrical circuit that is disposed so as to cover the opening of the first case and is electrically connected to the electronic component ;
Before Stories second sidewall is in the first state of being fitted to overlap the inside of the side wall, it has a projecting portion at least partially projects from the said first side wall,
A flange portion is formed on the first side wall,
The structure is
A third side wall formed with a flange part in contact with the flange part of the first side wall and disposed outside the protruding portion of the second side wall;
A relative position between the second side wall and the first terminal portion is determined according to a relative position between the second side wall and the first terminal portion, and is electrically connected to the electric circuit and the first terminal portion. 2 terminal portions,
The electronic structure is an electronic unit arranged to cover the opening along the protruding portion so that the first terminal portion and the second terminal portion are positioned at a predetermined relative position . The first case is:
A first bottom having a peripheral edge connected to the first side wall;
The second case is:
A peripheral portion connected to the second side wall, and further comprising a second bottom portion arranged to overlap the first bottom portion;
The electronic unit is
The electronic unit according to claim 1, further comprising a filling portion that is filled in the second case and fixes a position of the electronic component and the first terminal portion. The first case is made of metal;
The second case is made of an insulating resin,
The electronic unit according to claim 2, wherein the filling portion is made of an insulating resin. The electronic component is
A plurality of capacitors each having first and second electrodes;
The first terminal portion is
A first terminal to which the first electrodes of the plurality of capacitors are connected in common;
The electronic unit according to claim 1, further comprising: a second terminal to which the second electrodes of the plurality of capacitors are connected in common. The first terminal portion is
Including a first plate-like terminal provided with a first hole;
The second terminal portion is
Including a second plate-like terminal provided with a second hole;
The electronic unit is
The first, using said second hole first, further comprising a screw for connecting the second plate-like terminal, the electronic unit according to claim 1. The electronic unit according to claim 5, wherein the predetermined relative position is a position where the first and second plate-like terminals can be connected using the first and second holes by the screw. The electrical circuit is
A booster that boosts the voltage of the battery;
An inverter that drives the motor in response to the output of the booster,
The electronic component is
The electronic unit according to claim 1 , further comprising a capacitor that stabilizes an output voltage of the boosting unit. Before Ki突 out portion, the outer surface facing the third sidewall of is formed so as to rise toward the inner side than the vertical, the electronic unit according to claim 1. Before SL in the third side wall of the working hole for connecting the second terminal portion and the first terminal portion from the outside of the electronic unit is provided,
Protruding length of the impact out portion is shorter than the distance from the flange portion of the third side wall to said working hole, electronic unit according to claim 1. A first case made of metal having a first side wall and a first bottom part having a peripheral edge connected to the first side wall;
A second case made of insulating resin having a second side wall and a second bottom;
An electronic component housed inside the second case;
A filling portion filled in the second case in order to fix the electronic component;
A relative position with respect to the second side wall is fixed, and includes a first terminal portion connected to the electronic component,
The second case is arranged inside the first case so that the second side wall and the second bottom part overlap the inside of the first side wall and the first bottom part, respectively.
In a state where the second case is disposed inside the first case, the second side wall has a protruding portion that protrudes more than the first side wall,
A structure that accommodates an electric circuit that is arranged to cover the opening of the first case and is electrically connected to the electronic component ;
The structure is
End and abuts against the first side wall, a third side wall disposed outside of the projecting portion,
A relative position between the second side wall and the first terminal portion is determined according to a relative position between the second side wall and the first terminal portion, and the second terminal portion is electrically connected to the electric circuit. ,
The electronic unit , wherein the first terminal portion and the second terminal portion are positioned at a predetermined relative position when the structure is disposed so as to cover the opening along the protruding portion .   The electronic unit according to claim 10, wherein the protruding portion of the second side wall is formed such that an outer surface facing the third side wall rises inward from the vertical. Before SL in the third side wall of the working hole for connecting the second terminal portion and the first terminal portion from the outside of the electronic unit is provided,
11. The electronic unit according to claim 10, wherein a protruding length of the protruding portion of the second side wall is shorter than a distance from an end portion of the third side wall contacting the first side wall to the working hole. .   The vehicle drive device carrying the electronic unit of any one of Claims 1-12.   The vehicle carrying the electronic unit of any one of Claims 1-12.

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