JP2006274921A - Electric pump unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact electric pump unit which can be installed in a narrow space. <P>SOLUTION: A motor 2 is adjacent to a pump 1 in its center axis A direction, and a controller 3 for motor drive is adjacent to a motor 2 in the center axis direction. In the electric pump unit in which the pump 1, motor 2, and controller 3 are arranged in parallel, the controller 3 has little influence on a dimension in a radial direction of the motor 2, so that radially compact structure is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electric pump unit used as, for example, a hydraulic pump of an automobile.

  In recent years, it has been considered to realize energy saving by using an electric pump as a hydraulic source of an automobile and finely controlling its output control and operation / stop control. In addition, by mounting the electric pump, it is possible to ensure the supply of hydraulic pressure to the drive system such as the transmission even when the engine is stopped due to idle stop. For such electric pumps, there is a demand for compactness and cost reduction. For this reason, it is proposed that the pump and the motor are integrated to be compact, and the number of parts is reduced (for example, patent document). 1).

JP 2002-31065 A (pages 3 to 4, FIG. 1)

The conventional electric pump as described above contributes to a certain size reduction and cost reduction by integrating the pump and the motor, but the connection between the electric pump and the controller for motor control is still insufficient. There is. That is, the controller installed in the passenger compartment and the electric pump installed near the transmission in the engine room are connected by a wire harness, but the presence of this wire harness has hindered further cost reduction. Therefore, an electric pump unit in which a controller is also integrated is desired. However, even if the controller is attached to the drive terminal on the radial side surface of the motor, depending on the size of the transmission, Since there is not enough room, the controller case may be in the way and cannot be installed.
In view of the conventional problems as described above, an object of the present invention is to provide a compact electric pump unit that can be mounted in a narrow space.

The electric pump unit of the present invention is provided adjacent to the pump and the central axis direction of the pump, and is provided adjacent to the motor in the central axis direction and a motor that rotationally drives the pump. And a controller for driving the motor.
Thus, the electric pump unit in which the pump, the motor, and the controller are arranged in the central axis direction has a configuration that is compact in the radial direction because the presence of the controller hardly affects the radial dimension of the motor.

The electric pump unit includes a press-molded motor case that houses a motor, and a press-molded product that is manufactured separately from the motor case, and includes a controller case that houses a controller. One case may be configured as a whole by being connected to each other.
Such a case structure can be manufactured at a lower cost as compared with a case where the entire case structure is formed by aluminum die casting.

In the electric pump unit, the bus bar serving as the motor drive terminal may be supported by an insulator of the stator in the motor, extend parallel to the central axis direction of the motor, and be electrically connected to the controller. .
In this case, the size of the electric pump unit in the radial direction can be suppressed and a compact configuration can be achieved.

The bus bar may be ultrasonically bonded to the motor coil.
Ultrasonic bonding is suitable for work in a small space. Further, there is no generation of gas that adversely affects the human body, and there is no need for shielding with an inert gas to prevent oxidation. Furthermore, ultrasonic bonding can be performed at low cost.

Further, in the electric pump unit, the bus bar is a bent bar, the middle part of which is embedded in the insulator, and one end part for connection with the controller and the other end part connected to the coil of the motor, The structure which protrudes from the surface of the said insulator may be sufficient.
In this case, even if, for example, TIG welding is performed on the coil wound around the other end portion and the other end portion is thermally deformed, the one end portion for connection with the controller is not affected. Accordingly, the one end of the bus bar and the controller can be reliably connected.

  According to the electric pump unit of the present invention, the pump, the motor, and the controller are arranged in the direction of the central axis of the pump, so that the presence of the controller hardly affects the radial dimension of the motor and the configuration is compact in the radial direction. . Therefore, the electric pump unit can be mounted even in a narrow space such as near the transmission.

  FIG. 1 is a cross-sectional view of an electric pump unit according to an embodiment of the present invention. In the figure, the electric pump unit is provided adjacent to the pump 1 in the direction of the central axis A with respect to the pump 1, and adjacent to the motor 2 in the direction of the central axis A. And a controller 3 for driving the motor. The center axis A is also the rotation center axis of the motor 2. Thus, the electric pump unit in which the pump 1, the motor 2, and the controller 3 are arranged in the direction of the central axis A has a configuration that is compact in the radial direction because the presence of the controller 3 hardly affects the radial dimension of the motor 2. . Therefore, the electric pump unit can be installed in a narrow space near the transmission.

  The motor 2 is a DC brushless sensorless motor having three-phase windings, and includes a stator 5 and a rotor 8 rotatably supported by a pair of ball bearings 6 and 7 in a motor case 4. The stator 5 is obtained by winding a coil 11 with an insulator (resin insulating layer) 10 interposed in a core 9. The insulator 10 is molded integrally with three bus bars 12 that serve as drive terminals for the motor 2. Each bus bar 12 extends in parallel to the central axis A from the right end portion of the insulator 10. Thereby, the expansion to a radial direction can be suppressed and it can be set as a compact structure. The end of the coil 11 is electrically connected to the bus bar 12.

  The pump 1 is a trochoid gear pump, and includes a pump housing 13, an outer gear 14 rotatably accommodated in the pump housing 13, an inner gear 15 that meshes with the outer gear 14, and a pump plate that covers the shaft end surface of the pump housing 13. 16. The inner gear 15 is attached to the end portion of the shaft 8 a extending in the axial direction from the rotor 8 and rotates integrally with the rotor 8. Thus, the motor 2 and the pump 1 are integrated by sharing the shaft 8a, thereby achieving downsizing and a reduction in the number of members. A seal 17 is provided around the shaft 8a to prevent oil in the pump 1 from leaking to the motor 2 side. The controller 3 includes a controller case 18, a lid 19 that covers the controller case 18 from the end, a substrate 20 attached to the inside of the controller case 18, and an electronic component 21 (only a large electronic component is illustrated) mounted on the substrate 20. And). A connector shell 22 is provided on the side surface of the controller case 18, and a connector pin 23 inside thereof is connected to a circuit on the substrate 20.

  2 is a cross-sectional view taken along line II-II in FIG. In FIG. 2, a hole 4 a for passing the bus bar 12 is formed on the end surface of the motor case 4. The bus bar 12 insulated and supported by the insulator 10 passes through the hole 4a, is inserted into the substrate 20 (FIG. 1), and is connected to an output circuit section (not shown) on the substrate 20.

  FIG. 3 is a perspective view showing the assembled state of the case in the electric pump unit, showing only the outer part of the case and the like, and omitting the internal structure. In the figure, a pump plate 16, a pump housing 13, a motor case 4, a controller case 18, and a lid 19 are combined with each other in the direction of the central axis A to constitute an electric pump unit. The motor case 4 in which the motor 2 is housed and the controller case 18 in which the controller 3 is housed are press-molded products separately, and the right end outer diameter of the motor case 4 is substantially equal to the left end inner diameter of the controller case 18. These cases 4 and 18 are connected to each other to form one case as a whole. The connection is made by press fitting, shrink fitting, adhesion or welding. In addition, a waterproof adhesive is applied to the gap to ensure waterproofness. Such a case structure can be manufactured at a lower cost as compared with a case where the entire case structure is formed by aluminum die casting.

  Five connection pieces 4 b are formed on the outer periphery of the end of the motor case 4 so as to protrude outward. These connection pieces 4 b are bent in a state where the pump housing 13 and the pump plate 16 are combined with the motor case 4, and are fitted into the recesses 16 a of the pump plate 16. The controller case 18 hardly protrudes in the radial direction of the motor case 4 except for the upper box-shaped portion. In addition, the amount of protrusion of the upper box-shaped part is slight. Accordingly, the controller case 18 does not occupy a large dimension in the radial direction, and the configuration is compact in the radial direction. Therefore, as described above, the electric pump unit can be mounted even in a narrow space near the transmission.

  Next, a connection form between the bus bar 12 and the coil 11 will be described. FIG. 4 is a perspective view showing a state where the end of the coil 11 is wound around the bus bar 12 protruding from the insulator 10. The bus bar 12 is made of pure copper (C1020) not subjected to tin plating. Moreover, the coil 11 is also a pure copper wire from which the covering of the wound portion is removed. The coil 11 and the bus bar 12 are electrically connected by welding the contact portion P between the pure copper by ultrasonic vibration. Such ultrasonic bonding is suitable for work in a narrow space. Further, there is no generation of gas that adversely affects the human body, and there is no need for shielding with an inert gas to prevent oxidation. Furthermore, ultrasonic bonding can be performed at low cost.

  FIG. 5 is a cross-sectional view showing another connection form of the bus bar 12 and the coil 11 separately from the above-described embodiment. The bus bar 12 is bent into a shape as shown in the figure. A midway part 12b of the bus bar 12 is embedded in the insulator 10, and a first bar 12a for connection to the controller 3 is provided at one end and the other end, respectively. And the 2nd bar | burr 12c connected with the coil 11 protrudes from the surface of the insulator 10 so that height may differ. The coil 11 is wound around the second bar 12c as shown in the figure, and then welded to the second bar 12c by TIG welding. Although the second bar 12c may be thermally deformed by TIG welding, this deformation has no effect on the first bar 12a. Therefore, the connection between the first bar 12a and the substrate 20 (the circuit thereof) of the controller 3 can be reliably performed.

  FIG. 6 is a cross-sectional view showing still another connection form between the bus bar 12 and the coil 11. The bus bar 12 includes a first bus bar 12 d supported by the insulator 10 and a second bus bar 12 e attached to the substrate 20 of the controller 3. By performing TIG welding in a state where the upper end surface of the first bus bar 12d and the lower end surface of the second bus bar 12e are in contact with each other, they can be welded to each other. The coil 11 is welded to the first bus bar 12d by ultrasonic bonding as in the case of FIG. The connection location of the coil 11 is within the range of the first bus bar 12d. Such a 1st bus-bar 12d has a site | part to which the coil 1 is ultrasonically joined, and two junction sites of the upper end surface by which TIG welding is carried out. The second bus bar 12e is electrically connected to the circuit on the substrate 20.

  In such a connection form, since the first bus bar 12d is not directly inserted into the substrate 20, the accuracy required for the mutual positional relationship between the first bus bar 12d and the substrate 20 is relaxed, and manufacturing is easy. Even if the positions of both end faces of the first bus bar 12d and the second bus bar 12e do not exactly match each other, an electrically sufficient connection state can be obtained by TIG welding the end faces. Moreover, since the shape of the first bus bar 12d and the second bus bar 12e is simple, the manufacturing is easy and the cost is low.

It is sectional drawing of the electric pump unit by one Embodiment of this invention. It is the II-II sectional view taken on the line in FIG. It is a perspective view which shows the assembly state of the case in an electric pump unit, shows only outer parts, such as a case, and has omitted the internal structure. It is a perspective view which shows the connection form of a bus-bar and a coil. It is a perspective view which shows the other connection form of a bus-bar and a coil. It is a perspective view which shows the further another connection form of a bus-bar and a coil.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pump 2 Motor 3 Controller 4 Motor case 5 Stator 10 Insulator 11 Coil 12 Bus bar 12a 1st bar (one end part)
12b Middle part 12c 2nd bar (other end part)
12d 1st bus bar 12e 2nd bus bar 18 Controller case

Claims (5)

A pump,
A motor that is provided adjacent to the pump in the direction of its central axis, and that drives the pump to rotate;
An electric pump unit comprising: a motor driving controller provided adjacent to the motor in the central axis direction.   A motor case of a press-molded product that houses the motor, and a press-molded product that is made separately from the motor case, and includes a controller case that houses the controller, and these cases are connected to each other The electric pump unit according to claim 1, wherein one case is constituted as a whole.   2. The electric pump unit according to claim 1, wherein a bus bar serving as a drive terminal of the motor is supported by an insulator of a stator in the motor, extends parallel to a central axis direction of the motor, and is electrically connected to the controller.   The electric pump unit according to claim 3, wherein the bus bar is ultrasonically bonded to a coil of the motor.   The bus bar is a bent bar, the middle part of which is embedded in the insulator, and one end part for connection with the controller and the other end part connected with the coil of the motor are from the surface of the insulator. The electric pump unit according to claim 3, which protrudes.

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