JP2007049788A - Distributing member for motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique which is fit to mount a power element on a mounting member built in a motor. <P>SOLUTION: Circular bus bars 40P and 40N are distributing members built in the motor, and are made roughly annular in entire form, and bends 42, which are made to draw roughly circular arcs, and plate-shaped flat parts 44 are made to range in roughly annular form. A switching element is mounted directly on the flat part 44. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a motor power distribution member for supplying power to a motor.

  Conventionally, there is a technique in which a central power distribution member having a ring-shaped bus bar is incorporated in a three-phase DC brushless motor, and wiring connection between a power source and a winding is performed using the central power distribution member. The ring-shaped bus bar is formed, for example, by bending a conductive metal plate material in a band shape into a substantially annular shape by curving it in the thickness direction.

  Such a technique is disclosed in Patent Document 1, for example.

JP 2003-134759 A

  Incidentally, in recent years, there has been a demand for downsizing and the like regarding power conversion devices mounted on electric vehicles such as hybrid vehicles and fuel cell vehicles. However, in the technique disclosed in Patent Document 1, it is necessary to provide a switching element that constitutes an inverter separately from a motor incorporating a ring-shaped bus bar. For this reason, there exists a tendency for the whole structure to enlarge.

  Then, the subject of this invention is providing the technique suitable for mounting a power element on the power distribution member integrated in the motor.

  A motor power distribution member according to the present invention is a motor power distribution member incorporated in a motor, and is formed such that a curved portion formed so as to draw a substantially arc shape and a flat plate-like flat portion are connected in a substantially annular shape. Is.

  In this case, the power element may be mounted on the flat portion by electrically and mechanically connecting one of the electrodes to one main surface of the flat portion.

  Alternatively, the power element may be mounted on the flat portion by fixing one of the electrodes to one main surface of the flat portion using a conductive adhesive inclusion.

  Or the said power element may be mounted in the said flat part in the state which connected the one main surface to the one main surface of the said flat part thermally.

  Alternatively, in the state where the power element is in direct contact with one main surface of the flat portion, or indirectly through an interposed member having excellent thermal conductivity, It may be mounted on the flat part.

  According to the motor power distribution member of the present invention, the motor power distribution member incorporated in the motor is formed so that the curved portion formed so as to draw a substantially arc shape and the flat plate-like flat portion are connected in a substantially annular shape. Therefore, the power element can be easily mounted on the main surface of the flat portion.

  Furthermore, when the power element is mounted on the flat part by electrically and mechanically connecting one of the electrodes to one main surface of the flat part, the power element can be easily attached to the power distribution member for the motor. It can be mounted while being electrically connected.

  Alternatively, when the power element is mounted on the flat part by fixing one of its electrodes to one main surface of the flat part using a conductive adhesive inclusion, the power element is distributed to the motor. It can be mounted while being easily electrically connected to the member.

  In addition, when the power element is mounted on the flat portion in a state where one main surface thereof is thermally connected to one main surface of the flat portion, heat generated in the power element can be easily distributed. Heat can be easily dissipated by transmitting to the member.

  Alternatively, in the state where the power element is in direct contact with one main surface of the flat portion, or indirectly through an interposed member having excellent thermal conductivity, When mounted on the flat portion, the heat generated in the power element can be easily transferred to the power distribution member and easily dissipated.

  Hereinafter, an annular bus bar which is a power distribution member for a motor according to an embodiment of the present invention will be described.

  FIG. 1 is a block diagram showing an automobile to which a motor incorporating an annular bus bar is applied. The annular bus bar is a member that is incorporated in a traveling motor 20 (for example, a three-phase DC brushless motor) of an electric vehicle including a hybrid vehicle, a fuel cell vehicle, and the like and distributes power to a motor coil in the motor 20.

  That is, in the electric vehicle, the battery 12 is connected to the boost converter 14 via the relay 13. The boost converter 14 boosts the DC voltage output from the battery 12 and provides the boosted voltage to the inverter circuit 30. The inverter circuit 30 converts the DC power from the battery 12 side to AC power and supplies power to the motor 20 under the control of an inverter control circuit 38 that is separate from the motor 20 and the inverter circuit 30.

  FIG. 2 is a circuit diagram showing an inverter circuit. In the present embodiment, a three-phase AC motor is assumed as the motor 20, and the inverter circuit 30 is configured as a three-phase inverter circuit for driving the three-phase AC motor. That is, the inverter circuit 30 includes, as power elements, the high arm side switching elements 32a, 32b, 32c in the U phase, V phase, and W phase of the motor 20, and the low arm side switching elements 34a, 34b in each layer. , 34c. As these high arm side switching elements 32a, 32b, 32c and low arm side switching elements 34a, 34b, 34c, for example, various power switching elements such as a power MOSFET, a power junction transistor, and an IGBT are used. Here, an example in which the switching elements 32a, 32b, 32c, 34a, 34b, and 34c are power MOSFETs will be described. The switching elements 32a, 32b, 32c, 34a, 34b, and 34c may be in the form of a bare chip or packaged.

  The drains of the high arm side switching elements 32a, 32b, and 32c are all connected to the plus (+) side power source, and their sources are connected to the drains of the low arm side switching elements 34a, 34b, and 34c of the same phase. The sources of the low arm side switching elements 34a, 34b, and 34c are all connected to the minus (−) side power source. The connection points between the sources of the high arm side switching elements 32a, 32b, and 32c and the drains of the low arm side switching elements 34a, 34b, and 34c are connected to the U phase, V phase, and W phase of the motor 20, respectively. The The gate terminals 33a, 33b, 33c, 35a, 35b, and 35c, which are control input terminals of the switching elements 32a, 32b, 32c, 34a, 34b, and 34c, are connected to the control signal output terminal of the inverter control circuit 38, respectively. ing. Then, the switching elements 32a, 32b, 32c, 34a, 34b, and 34c are turned on and off at a timing according to the control signal supplied from the inverter control circuit 38.

  The annular bus bar is integrated into the motor 20 and used as power supply wiring in the inverter circuit 30 as described above.

  3 is an explanatory view showing an installation example of the annular bus bar in the motor, FIG. 4 is a view showing an example of the annular bus bar, FIG. 5 is a view showing another example of the annular bus bar, and FIG. FIG.

  That is, assuming the inverter circuit 30 as described above, a pair of direct current power supply annular bus bars 40P and 40N (see FIG. 4) and a plurality (here, U, V, and W) are used as power supply wirings. The three ring-shaped bus bars 40U, 40V, 40W (see FIG. 5) for supplying AC power are used.

  The annular bus bars 40P, 40N, 40U, 40V, and 40W are formed in a substantially annular overall shape and are formed with different diameters. These annular bus bars 40P, 40N, 40U, 40V, and 40W are arranged in a concentric manner on substantially the same plane, and are insulated with an insulating resin or the like on one end face side of the motor 20 formed in a substantially cylindrical shape. It is held by a holder 28 made of a material. Here, the term “substantially annular” only needs to be formed in an approximately annular shape, and includes an annular shape having a partial cut as shown in FIGS. 4 and 5.

  At least one of the switching elements 32a, 32b, 32c, 34a, 34b, and 34c is mounted on the annular bus bars 40P, 40N, 40U, 40V, and 40W.

  Here, at least one of the switching elements 32a, 32b, 32c, 34a, 34b, and 34c is mounted on the annular bus bars 40P and 40N shown in FIG. That is, the annular bus bars 40P and 40N are curved so as to draw a substantially arc shape, for example, by punching a conductive plate material such as a metal plate into a substantially strip shape and bending it into a substantially annular shape along its thickness direction. The part 42 and the flat plate-like part 44 are formed so as to be connected in a substantially annular shape. The flat portion 44 is a partial flat plate portion in the circumferential direction of the annular bus bars 40P and 40N. The flat portion 44 is formed to have a size that allows the mounting of the switching elements 32a, 32b, 32c, 34a, 34b, and 34c to be mounted. Each switching element 32a, 32b, 32c, 34a, 34b, 34c is directly mounted on the flat portion 44 in a manner to be described later.

  In addition, the extended piece 46 extended in the radial direction outer side is formed in cyclic | annular bus-bar 40P, 40N. DC power is supplied from the outside through the extended piece 46.

  Note that the annular bus bars 40U, 40V, and 40W shown in FIG. 5 are formed in a generally arc shape by punching a conductive plate material such as a metal plate into a substantially strip shape and bending it into a substantially annular shape along its thickness direction. It is formed in a substantially annular shape.

  Of course, at least one of the switching elements 32a, 32b, 32c, 34a, 34b, and 34c is attached to the annular bus bars 40U, 40V, and 40W according to the circuit example for driving the motor, the electrode layout of the switching elements, and the like. You may make it mount. In such a case, a flat portion similar to the flat portion 44 may be formed on the annular bus bars 40U, 40V, and 40W.

  FIG. 7 is a diagram showing a state where a surface-mount type switching element is mounted on the flat portion. That is, the switching element 50 (here, the switching elements 32a, 32b, 32c, 34a, 34b, and 34c are represented as the switching element 50) is represented by a DC power supply, the U phase, the V phase, and the W of the motor 20. It has an electrode 52 connected to one of the phases. Further, another electrode is provided on the other main surface of the switching element 50. The switching element 50 is mounted by electrically connecting the electrode 52 to one main surface of the flat portion 44. The electrode 52 can be electrically connected to one main surface of the flat portion 44 by using a conductive adhesive inclusion 56 such as solder or silver paste and electrically and mechanically connected. A configuration in which the electrode 52 is brought into pressure contact with one main surface of the flat portion 44 and electrically connected using a known fixing means such as a stopper or a caulking is adopted.

  The other electrodes in the switching element 50 are electrically connected to wirings such as other annular bus bars 40U, 40V, 40W using wire bonding or the like.

  FIG. 8 is a diagram showing a state in which a lead type switching element packaged in a flat portion is mounted. That is, the switching element 150 (herein, the switching elements 32a, 32b, 32c, 34a, 34b, and 34c are represented as the switching element 150) is connected to a DC power source, a motor on one side of the main body 151. It has a lead electrode 152 connected to one of 20 U-phases, V-phases, and W-phases, and another lead electrode. A mounting piece 154 extends to the other side of the main body 151, and a screw stop hole 154h is formed in the mounting piece 154.

  The switching element 150 is mounted on the flat portion 44 with one main surface thereof thermally connected to one main surface of the flat portion 44.

  More specifically, in the switching element 150, the screw Sa is inserted into the screw hole 154 h and the screw hole 44 h formed in the flat part 44 in a state where the mounting piece 154 and the flat part 44 are overlapped with each other. By screwing Sb, it is fixed by screwing. Note that one main surface of the mounting piece 154 that is one main surface of the switching element 150 may be in direct contact with the flat portion 44, and an interposition member 156 having excellent thermal conductivity is interposed therebetween. Thus, heat dissipation may be improved. When the insulation between the annular bus bars 40U, 40V, 40W and the switching element 150 is not necessary as the interposition member 156, heat dissipation grease, solder, or the like can be used. A mica plate or an insulating heat conductive sheet can be used.

  The lead electrode 152 of the switching element 150 is electrically connected to the mounted annular bus bars 40U, 40V, 40W by welding, soldering, or the like. The remaining lead electrodes are electrically connected to other annular bus bars 40U, 40V, 40W and the like using soldering, welding, or wire bonding as necessary.

  According to the annular bus bars 40P and 40N configured as described above, the curved portion 42 formed so as to draw a substantially arc shape and the flat plate-like flat portion 44 are formed so as to be substantially annularly connected. 44 is suitable for mounting the switching elements 50 and 150. For this reason, the switching elements 50 and 150 can be easily mounted on the main surface of the flat portion 44. Then, by incorporating the annular bus bars 40P and 40N on which the switching elements 50 and 150 are mounted in the motor 20 in this manner, the motor 20 and the inverter circuit 30 can be integrated while reducing the size and cost.

  In particular, when the switching element 50 is mounted on the flat portion 44 by electrically and mechanically connecting one of its electrodes 52 to one main surface of the flat portion 44, the switching element 50 is connected to the annular bus bar 40P, It can be mounted while being easily electrically connected to 40N.

  Further, when the switching element 150 is mounted on the flat portion 44 in a state in which one main surface thereof is thermally connected to one main surface of the flat portion 44, the heat generated in the switching element 150 is easily circularized. The heat can be easily dissipated by being transmitted to the bus bars 40P and 40N.

It is a block diagram which shows the motor vehicle which applied the motor incorporating the cyclic | annular bus bar. It is a circuit diagram which shows an inverter circuit. It is explanatory drawing which shows the example of installation of the cyclic | annular bus bar in a motor. It is a figure which shows an example of a cyclic | annular bus bar. It is a figure which shows the other example of a cyclic | annular bus bar. It is a principal part enlarged view of FIG. It is a figure which shows the state which mounted the surface mounting type switching element in the flat part. It is a figure which shows the state which mounted the lead-type switching element packaged in the flat part.

Explanation of symbols

20 Motor 30 Inverter circuit 32a, 32b, 32c, 34a, 34b, 34c Switching element 40P, 40N Annular bus bar 42 Bending part 44 Flat part 50, 150 Switching element 52 Electrode 152 Lead electrode

Claims (5)

A power distribution member for a motor incorporated in a motor,
A motor power distribution member formed such that a curved portion formed so as to draw a substantially arc shape and a flat plate-like flat portion are connected in a substantially annular shape. The motor power distribution member according to claim 1,
A power distribution member for a motor, wherein the power element is mounted on the flat portion by electrically and mechanically connecting one of the electrodes to one main surface of the flat portion. The motor power distribution member according to claim 1,
A power distribution member for a motor, wherein the power element is mounted on the flat portion by fixing one of its electrodes to one main surface of the flat portion using a conductive adhesive inclusion. The motor power distribution member according to claim 1,
A power distribution member for a motor, wherein the power element is mounted on the flat portion in a state where one main surface thereof is thermally connected to one main surface of the flat portion. The motor power distribution member according to claim 1,
In the state where the power element has its one main surface in direct contact with one main surface of the flat portion or indirectly through an interposed member having excellent thermal conductivity, the flat portion A motor power distribution member to be mounted.

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