JPH0740845A - Motor-driven type fluid pressure pump - Google Patents

Abstract

PURPOSE:To improve a motor part cooling effect by arranging pressure fluid flow chamber so as to surround a motor part outer periphery to communicate the flow chamber with a pump chamber inlet port. CONSTITUTION:A rotor 5 is spline-engaged with the tip part of the drive shaft 3 of an electric motor, and plural vanes are fitted to the motor 5 to abut on the cam ring of a pump chamber 6. A reservoir tank 7 is arranged so as to cover the outer periphery of a pump housing 2 to be communicated with the sucking port 8 of the pump chamber 6. A cylindrical pressure fluid flow chamber 11 is arranged in the outer periphery of the motor housing 1 and is communicated with the reservoir tank 7, and an inlet port plug 13 is fitted to the opposite side of a pump part. This constitution supplies pressure fluid flowed-in to the pump part via the outer periphery of the motor part, absorbing the heat of the motor part into the pressure fluid flowing the outer periphery.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a fluid pressure pump integrated with an electric motor in an electric motor driven type power steering device.

[0002]

2. Description of the Related Art Conventionally, as a power steering device to which an electric motor driven fluid pressure pump is applied, there is one disclosed in, for example, Japanese Patent Laid-Open No. 3-132470. An electric motor drive type fluid pressure pump used in this device has a structure as shown in FIG. 4, in which a motor housing 1 arranged on the left side is connected to a pump housing 2 arranged on the right side. is doing.

The drive shaft 3 of the electric motor housed in the motor housing 1 extends horizontally toward the pump chamber 6 formed by the pump housing 2, and the rotor 5 of the pump is spline-fitted at the tip thereof. I am fit. A plurality of vanes are radially attached to the rotor 5, and the plurality of vanes can come into contact with the cam ring of the pump chamber 6 by the rotation of the rotor 5.

A reservoir tank 7 is arranged so as to cover the outer periphery of the pump housing 2, and the reservoir tank 7 communicates with the suction port of the pump chamber 6. Further, the pump chamber 6 and the reservoir tank 7 communicate with each other via a relief valve. Incidentally, 13 is an inlet port plug communicating with the reservoir tank 7, and 10 is a discharge port plug communicating with the pump chamber 6.

By driving the electric motor,
The rotor 5 rotates via the drive shaft 3, and the vanes incorporated in the rotor 5 radially pop out due to the centrifugal force and move along the cam ring inner elliptical curved surface. As a result, the pressure fluid in the reservoir tank 7 is sucked into the pump chamber 6 through the suction port 8 and discharged through the discharge port plug 10, and the high pressure fluid is supplied to the power steering gear device.

[0006]

However, in the electric motor drive type fluid pressure pump having the above-mentioned structure, the pump and the motor are integrally assembled, but the flow passage of the pressure fluid has the pump portion. However, there is a problem that the cooling of the motor unit is insufficient because the cooling of the motor unit is limited to air cooling.

The present invention has been made in view of the above problems, and an object thereof is to improve the cooling efficiency of the motor section.

[0008]

In order to achieve the above object, an electric motor drive type fluid pressure pump of the present invention has an electric motor integrally assembled to a fluid pressure pump, and the fluid is driven by the electric motor. In an electric motor drive type fluid pressure pump in which a pressure pump operates, a pressure fluid circulation chamber is provided so as to surround the outer periphery of the motor portion, and the pressure fluid circulation chamber is communicated with the inlet port of the pump chamber to It is characterized in that the pressure fluid is supplied to the fluid pressure pump through the fluid communication chamber.

At this time, it is preferable that an elastic body is arranged on the outer periphery of the pressure fluid circulation chamber and that the discharge side of the relief valve of the fluid pressure pump communicates with the pressure fluid circulation chamber.

[0010]

[Function] By supplying the pressure fluid to the pump through the outer periphery of the motor part, the heat generated in the motor part is
It is absorbed by the pressure fluid flowing around the outer periphery thereof, and the motor unit is cooled accordingly. Here, not the pressure fluid discharged from the pump but the inflowing pressure fluid was circulated to the outer periphery of the motor because the pressure fluid having a high pressure after discharge has a temperature raised by adiabatic compression, This is because the inflowing pressure fluid side is cooled by an oil cooler or the like and therefore has high cooling efficiency.

Further, when the motor is driven, a radiated sound such as a motor sound is radiated from the housing of the motor portion to the atmosphere, and the pressure fluid circulation chamber absorbs the radiated sound. Further, as described in claim 2, when the elastic body is arranged on the outer periphery of the pressure fluid circulation chamber, the effect of blocking the radiated sound is further improved. Also, if the discharge side of the relief valve is in communication with the pressure fluid flow chamber, the pressure fluid in the pump chamber will flow into the pressure fluid flow chamber via the relief valve during relief that occurs when the steering wheel is stationary. It

At the time of the relief, the hydraulic pressure of the pressure fluid in the circuit rises to the maximum hydraulic pressure, and the motor is in the most heated state. ing. For this hot fluid,
The pressure fluid having a temperature lower than that of the pressure fluid is cooled by flowing through the relief valve to cool the pressure fluid in the pressure fluid flow chamber, and the pressure fluid in the pressure fluid flow chamber that has stagnated due to the stationary flow is Be stirred.

At this time, pressure fluctuations occur in the pressure fluid circulation chamber, but the pulsation of the pressure fluid due to the fluctuations is absorbed by the elastic body.

[0014]

Embodiments of the present invention will be described with reference to the drawings.
First, the configuration will be described. As shown in FIG. 1, a motor housing 1 arranged on the left side and housing an electric motor is
It is connected to the pump housing 2 arranged on the right side. The drive shaft 3 of the electric motor is rotatably supported by the motor housing 1 via a bearing 4 and extends toward the pump side, and the rotor 5 is coaxially spline-fitted to the tip end thereof.

The rotor 5 is housed in a pump chamber 6 formed by the pump housing 2, and a plurality of vanes are attached to the rotor 5. Due to the centrifugal force generated by the rotation of the rotor 5, the plurality of vanes are formed. It is possible to contact the cam ring of the pump chamber 6. A reservoir tank 7 is arranged so as to cover the outer periphery of the pump housing 2, and the reservoir tank 7 communicates with a suction port 8 of the pump chamber 6. Further, the pump chamber 6 and the reservoir tank 7 communicate with each other via a relief valve 9.

Reference numeral 10 is a discharge port plug communicating with the pump chamber 6. A cylindrical pressure fluid flow chamber 11 is coaxially arranged on the outer periphery of the motor housing 1, and the pressure fluid flow chamber 11 communicates with the reservoir tank 7 through an inflow through hole 12. An input port plug 13 is attached to the pressure fluid circulation chamber 11 at a position opposite to the pump portion.

On the outer circumference of the pressure fluid circulation chamber 11,
An elastic body 14 such as a rubber body is arranged. As shown in FIG. 2, the discharge port plug 10 is connected to the input port of the power steering gear device 18 via a high pressure hose 16 and a high pressure tube 17, and returns to the discharge port of the power steering gear device 18 to return to the hose. One end of 18 is connected. The other end of the return hose 18
The return tube 20 is connected to the return tube 20,
It extends forward along the side frame of the vehicle body and is connected to the oil cooler tube 21.

The oil cooler tube 21 is arranged in the vehicle width direction along the front cross member 22 of the vehicle body, and the low pressure side of the oil cooler tube 21 is an input port plug provided in the pressure fluid circulation chamber 11. Thirteen
It is connected to the. Then, in the electric motor driven fluid pressure pump P having the above-described configuration, the rotor 5 is rotated via the drive shaft 3 by driving the electric motor, and the vanes incorporated in the rotor 5 are radially generated by the centrifugal force. The cam ring moves along the inner elliptical curved surface.

As a result, the hydraulic fluid in the reservoir tank 7 is sucked into the pump chamber 6 through the suction port 8 and is discharged through the discharge port plug 10, and the discharged high-pressure fluid is a high-pressure hose. 16 through the high pressure tube 17 and the power steering gear device 18
Is supplied to. In addition, the power steering gear device 18
The pressure fluid discharged from is sent to the front side of the vehicle body through the return hose 18 and the return tube 20 and is air-cooled when passing through the oil cooler tube 21.

Subsequently, the pressure fluid cooled while passing through the oil cooler tube 21 is sent to the pump side and supplied to the pressure fluid circulation chamber 11 via the input port plug 13, and the inside of the pressure fluid circulation chamber 11 is supplied. The fluid under pressure flows to the reservoir tank 7 via the inflow through hole 12. Thus, in the electric motor driven fluid pressure pump P of the present embodiment,
Since the cooled pressure fluid flows through the outer circumference of the motor housing 1, the heat generated from the motor by driving is absorbed by the pressure fluid flowing through the outer circumference, and thus,
The motor is cooled.

Further, a radiated sound such as a motor sound is radiated from the motor upon driving, and the radiated sound is also absorbed by the pressure fluid in the pressure fluid flow chamber 11 and the elastic body 14 and is thus insulated. In the above embodiment, the tank-integrated pump structure is described, but the electric motor driven fluid pressure pump P in which the reservoir tank 7 and the pump body are separate bodies.
The present invention may be applied to. In this case, the pressure fluid circulation chamber 11 is directly connected to the suction port 8 of the pump chamber 6.

Further, in the above embodiment, the pressure fluid circulation chamber 1
The elastic body 14 is arranged on the outer periphery of the elastic body 14.
May be omitted. In addition, the upper pressure fluid distribution chamber 11
The outer peripheral wall 11a side may be formed of a rubber body, and the elastic body 14 may be omitted. Next, a second embodiment will be described.

The electric motor drive type fluid pressure pump P of the second embodiment has a basic structure similar to that of the first embodiment, and the discharge side of the relief valve 9 is connected to the pressure fluid circulation chamber 11. The only difference is the connection. The electric motor drive type fluid pressure pump P of the second embodiment also has the same action and effect as the electric motor drive type fluid pressure pump P of the first embodiment.

During the steering steering operation, when the fluid pressure in the circuit rises and becomes the relief pressure, the pressure fluid in the pump chamber 6 is discharged through the relief valve 9 and the pressure fluid is discharged. It flows into the distribution chamber 11. At the time of the relief, the hydraulic pressure of the pressure fluid in the circuit rises to the maximum hydraulic pressure and the motor is in the most heated state, and the pressure fluid in the pressure fluid flow chamber 11 that absorbs the heat becomes high temperature. There is.

A pressure fluid having a temperature lower than the pressure fluid flows into the high temperature pressure fluid through the relief valve 9 to cool the pressure fluid in the pressure fluid flow chamber 11. The pressure fluid in the pressure fluid flow chamber 11 that stagnated when the flow stopped was agitated,
The cooling effect by the pressure fluid circulation chamber 11 at the time of stationary is improved.

At this time, a pressure fluctuation occurs in the pressure fluid flow chamber 11, but the pulsation of the pressure fluid due to the fluctuation is absorbed by the elastic body 14.

[0027]

As described above, in the electric motor drive type fluid pressure pump of the present invention, the effect of cooling the motor integrated with the pump is improved.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an electric motor drive type fluid pressure pump according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing a layout of piping connected to an electric motor drive type fluid pressure pump of an embodiment according to the present invention.

FIG. 3 is a partially cutaway side view showing an electric motor drive type fluid pressure pump of a second embodiment according to the present invention.

FIG. 4 is a partially cutaway side view showing a conventional electric motor driven fluid pressure pump.

[Explanation of symbols]

 3 Drive shaft 5 Rotor 6 Pump chamber 7 Reservoir tank 9 Relief valve 11 Pressure fluid flow chamber 12 Inflow through hole 14 Elastic body

Claims (2)

[Claims] 1. An electric motor drive type fluid pressure pump in which an electric motor is integrally assembled to a fluid pressure pump and the fluid pressure pump is operated by driving the electric motor. An electric motor drive type characterized by arranging a chamber, communicating the pressure fluid circulation chamber with the inlet port of the pump chamber, and supplying the pressure fluid to the fluid pressure pump through the pressure fluid communication chamber. Fluid pressure pump. 2. The electric motor according to claim 1, wherein an elastic body is arranged on the outer periphery of the pressure fluid circulation chamber, and the discharge side of the relief valve of the fluid pressure pump is communicated with the pressure fluid circulation chamber. Driven fluid pressure pump.