Pressure source unit

Abstract

A pressure source unit (1) includes: a hydraulic pump (2) including a rotating shaft (21) and a pump housing (22); an electric motor (6) including an output shaft (61) connected to the rotating shaft (21) and a motor housing (62); and a connecting body (5) that is interposed between the pump housing (22) and the motor housing (62) and connects the pump housing (22) and the motor housing (62). A pump housing (22) or a connector (5) is fixed to a machine (9) on which a pressure source unit (1) is mounted, and a motor housing (62) is supported by the machine (9) via an elastic body (7).

Description

Technical Field

[0001] The present disclosure relates to a pressure source unit used in a hydraulic circuit. Background Art

[0002] Conventionally, a pressure source unit including a hydraulic pump and an electric motor has been known. For example, a pressure source unit mounted on an injection molding machine is disclosed in FIG. 6 of Patent Document 1. In Patent Document 1, the pressure source unit is referred to as a "hydraulic generating device".

[0003] Specifically, in the pressure source unit, a sleeve connecting the pump housing and the motor housing is interposed between the pump housing of the hydraulic pump and the motor housing of the electric motor, and the rotating shaft of the hydraulic pump is connected to the output shaft of the electric motor within the sleeve. The sleeve is fixed to the injection molding machine via a bracket.

[0004] Prior Art Documents Patent Documents Patent Document 1: Japanese Patent Laid-Open No. 11-314257 Summary of the Invention

[0005] Problems to be Solved by the Invention However, in the pressure source unit as described above, since the electric motor is in a floating state, it is desired to suppress the vibration of the electric motor.

[0006] Therefore, an object of the present disclosure is to provide a pressure source unit capable of suppressing the vibration of an electric motor.

[0007] Means for Solving the Problems The present disclosure provides a pressure source unit mounted on a machine, comprising: a hydraulic pump including a rotating shaft and a pump housing; an electric motor including an output shaft connected to the rotating shaft and a motor housing; and a connecting body interposed between the pump housing and the motor housing and connecting the pump housing and the motor housing, wherein the pump housing or the connecting body is fixed to the machine, and the motor housing is supported by the machine via an elastic body.

[0008] Effects of the Invention According to the present disclosure, a pressure source unit capable of suppressing the vibration of an electric motor is provided. Brief Description of the Drawings

[0009] Figure 1 is a cross-sectional view of a pressure source unit according to an embodiment; Figure 2 is a cross-sectional view of a pressure source unit according to a modified example. Detailed Description of the Invention

[0010] Figure 1The pressure source unit 1 of one embodiment is shown. The pressure source unit 1 is mounted on the machine 9. Additionally, in Figure 1 only a part of the machine 9 is depicted. For example, the machine 9 can be a construction machine such as a hydraulic excavator or a wheel loader, or an industrial machine such as an injection molding machine or a stamping device.

[0011] Specifically, the pressure source unit 1 includes a hydraulic pump 2 and an electric motor 6, and includes a connecting body 5 between the hydraulic pump 2 and the electric motor 6. The hydraulic pump 2 and the electric motor 6 are arranged horizontally. In this embodiment, the hydraulic pump 2 and the electric motor 6 are arranged coaxially.

[0012] In this embodiment, the hydraulic pump 2 is a swash plate pump which is one of the axial piston pumps. However, the hydraulic pump 2 can also be a bent axis pump which is another axial piston pump. Or, the hydraulic pump 2 can also be other types of pumps such as a vane pump, a gear pump, or a screw pump.

[0013] The hydraulic pump 2 includes: a rotating shaft 21 extending in the horizontal direction; and a pump housing 22 which rotatably supports the rotating shaft 21 via a plurality of bearings 23, 24. The pump housing 22 is hollow, and a valve plate 31, a cylinder block 32, and a swash plate 36 are accommodated in the pump housing 22.

[0014] More specifically, the pump housing 22 has: a front wall which is penetrated by the rotating shaft; a valve cover which is opposite to the front wall in the axial direction of the rotating shaft 21; and a peripheral wall which surrounds the space between the front wall and the valve cover. An intake passage and a discharge passage are formed on the valve cover.

[0015] The valve plate 31 is fixed to the valve cover. An arc-shaped intake port communicating with the intake passage and an arc-shaped discharge port communicating with the discharge passage are formed on the valve plate 31. The intake port and the discharge port are located on the same circumference around the rotating shaft 21.

[0016] The cylinder block 32 is fixed to the rotating shaft 21 and rotates together with the rotating shaft 21 while sliding with the valve plate 31. A plurality of cylinder bores are formed in the cylinder block 32. Some of the cylinder bores communicate with the intake port, and some communicate with the discharge port.

[0017] A plurality of pistons 33 are respectively inserted into the cylinder bores of the cylinder block 32. A plurality of slipper shoes 34 are respectively mounted on the heads of the pistons 33. In this embodiment, the slipper shoes 34 slide with a slipper plate 35 fixed to the swash plate 36. However, the slipper shoes 34 can also slide directly with the swash plate 36.

[0018] The electric motor 6 includes: an output shaft 61 extending in the horizontal direction; and a motor housing 62 which rotatably supports the output shaft 61 via a plurality of bearings. The motor housing 62 is hollow, and a rotor and a stator are accommodated in the motor housing 62. The rotor is fixed to the output shaft 61, and the stator is fixed to the motor housing 62.

[0019] In this embodiment, the rotating shaft 21 of the hydraulic pump 2 and the output shaft 61 of the electric motor 6 are connected by a cylindrical coupling 4. A spline-shaped tooth surface is formed on the inner peripheral surface of the coupling 4. On the other hand, spline-shaped tooth surfaces are formed on the outer peripheral surfaces of the rotating shaft 21 and the output shaft 61, and these tooth surfaces mesh with each other.

[0020] However, the rotating shaft 21 and the output shaft 61 do not necessarily have to be connected by the coupling 4. For example, one end of either the rotating shaft 21 or the output shaft 61 may be hollow, and the other may be inserted therein, and the spline-shaped tooth surfaces formed on the rotating shaft 21 and the output shaft 61 may directly mesh. Alternatively, the rotating shaft 21 and the output shaft 61 may also be connected via gears that are fixed to the rotating shaft 21 and the output shaft 61 and mesh with each other.

[0021] The connecting body 5 is interposed between the pump housing 22 and the motor housing 62 and connects the pump housing 22 and the motor housing 62. In this embodiment, the connecting body 5 is a cylindrical shape that extends in the axial direction of the rotating shaft 21 and the output shaft 61, that is, in the horizontal direction, and the rotating shaft 21 and the output shaft 61 are accommodated in the connecting body 5.

[0022] In this embodiment, the pump housing 22 is fixed to the machine 9, and the connecting body 5 and the electric motor 6 float in the air in such a manner as to form a cantilever beam with the pump housing 22 as a fulcrum. Moreover, the end of the motor housing 62 on the side opposite to the connecting body 5 is supported by the machine 9 via the elastic body 7. That is, the elastic body 7 is joined to the end of the motor housing 62 and the machine 9.

[0023] For example, when the pressure source unit 1 is arranged in the room of the machine 9, the motor housing 62 may be supported by the floor of the room via the elastic body 7, or may be supported by the lateral wall surface of the room via the elastic body 7. The elastic body 7 may be, for example, a block made of rubber.

[0024] However, the elastic body 7 does not necessarily have to be joined to the end of the motor housing 62, and may be interposed between the motor housing 62 and the machine 9 in such a manner as to be in surface contact with the lower surface of the motor housing 62. At this time, the elastic body 7 may be a compression coil spring or a leaf spring or the like.

[0025] As described above, in the pressure source unit 1 of this embodiment, since the motor housing 62 is supported by the machine 9 via the elastic body 7, vibration of the electric motor 6 can be suppressed. In other words, the vibration of the electric motor 6 is absorbed by the elastic body 7.

[0026] <Modification Example> The present disclosure is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present disclosure.

[0027] For example, the hydraulic pump 2 may be a series pump or a parallel pump provided with two piston pump mechanisms each including a valve plate 31, a cylinder block 32, a piston 33, a slipper 34, and a swash plate 36. Thus, when the hydraulic pump 2 is a series pump or a parallel pump, by fixing the pump housing 22 of the relatively heavy hydraulic pump 2 to the machine 9, the influence of vibration is reduced.

[0028] Alternatively, as in the hydraulic system 1A of the modified example shown in Figure 2 , the connecting body 5 may be fixed to the machine 9 instead of the pump housing 22 of the hydraulic pump 2. In Figure 2 , a bracket 51 extending downward from the connecting body 5 is integrally provided on the connecting body 5, and an elastic body 55 is interposed between the bracket 51 and the machine 9. That is, the connecting body 5 is fixed to the machine 9 via the bracket 51 and the elastic body 55. The elastic body 55 may be, for example, a block made of rubber. Thus, when the connecting body 5 is fixed to the machine 9, compared with the case of fixing the pump housing 22, since the length from the fixing position to the end of the electric motor 6 is shorter, the influence of vibration is reduced.

[0029] When the connecting body 5 is fixed to the machine 9, it is preferable that the end of the pump housing 22 on the side opposite to the connecting body 5 is also supported by the machine 9 via an elastic body 8. The elastic body 8 may be, for example, a block made of rubber.

[0030] For example, the elastic body 8 engages with the end of the pump housing 22 and the machine 9. However, the elastic body 8 does not necessarily have to engage with the end of the pump housing 22, and may be interposed between the pump housing 22 and the machine 9 in a manner of surface contact with the lower surface of the pump housing 22. At this time, the elastic body 8 may be a compression coil spring or a leaf spring or the like.

[0031] If it is the Figure 2 structure, vibration of the hydraulic pump 2 generated when the connecting body 5 is fixed to the machine 9 can be suppressed.

[0032] <Summary> As a first aspect, the present disclosure provides a pressure source unit mounted on a machine, the pressure source unit including: a hydraulic pump including a rotating shaft and a pump housing; an electric motor including an output shaft connected to the rotating shaft and a motor housing; and a connecting body interposed between the pump housing and the motor housing and connecting the pump housing and the motor housing, wherein the pump housing or the connecting body is fixed to the machine, and the motor housing is supported by the machine via an elastic body.

[0033] According to the above structure, since the motor housing is supported by the elastomer on the machine, vibration of the electric motor can be suppressed. In particular, in the case where the hydraulic pump is a series pump or a parallel pump, by fixing the pump housing of the relatively heavy hydraulic pump to the machine, the influence of vibration becomes smaller. Alternatively, in the case where the connecting body is fixed to the machine, compared with the case of fixing the pump housing, since the length from the fixing position to the end of the electric motor becomes shorter, the influence of vibration becomes smaller.

[0034] As a second aspect, in the first aspect, it may also be that the connecting body is fixed to the machine, and the pump housing is supported by the elastomer on the machine. According to this structure, vibration of the hydraulic pump generated when the connecting body is fixed to the machine can be suppressed.

[0035] As a third aspect, in the first or second aspect, for example, it may also be that the connecting body is a cylindrical shape that houses the rotating shaft and the output shaft.

Claims

1. A pressure source unit is a pressure source unit mounted on a machine, characterized in that, it comprises: a hydraulic pump including a rotating shaft and a pump housing; an electric motor including an output shaft connected to the rotating shaft and a motor housing; and a connecting body interposed between the pump housing and the motor housing and connecting the pump housing and the motor housing, the pump housing or the connecting body is fixed to the machine, the motor housing is supported by the machine via an elastic body.

2. The pressure source unit according to claim 1, characterized in that, the connecting body is fixed to the machine, the pump housing is supported by the machine via an elastic body.

3. The pressure source unit according to claim 1 or 2, characterized in that, the connecting body is tubular for accommodating the rotating shaft and the output shaft.

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