KR19990040230A - Pulsation Noise Reduction Device for Power Steering - Google Patents

Abstract

The present invention relates to a pulsation noise reduction device of a power steering apparatus, and means for reducing pulsation caused by a sudden flow rate change of a fluid on a supply line for supplying hydraulic oil pressurized from an oil pump to a control valve in a power steering apparatus. The purpose is to reduce the noise level in the interior of the vehicle.

The present invention for achieving the above object, a steering shaft (2) having a steering wheel (1) attached to the upper end, a steering column (3) for fixing the steering shaft (2) to the vehicle body, the steering A control valve 4 mounted on the lower part of the shaft 2 to control the flow of hydraulic oil during steering; an operation cylinder 5 for linear movement according to the rotational movement of the steering shaft 2; (4) an oil pump (6) for supplying pressurized hydraulic oil, an oil storage tank (7) for storing the hydraulic oil supplied to the oil pump (6), the control valve (4) and the oil pump (6) and oil In a power steering system composed of a supply line (8) and a recovery line (9) disposed for supply and recovery of hydraulic oil between storage tanks (7), the hydraulic oil pressurized from the oil pump (6) is controlled. Oil generated from the sudden flow rate change of the fluid flowing on the supply line (8) to be supplied to the valve (4) Is made of a so as to reduce a pulsating pulsation reducing means (11) is fitted.

Description

Pulsation Noise Reduction Device for Power Steering

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power steering apparatus in which a steering force is increased during a high speed driving of a vehicle. In particular, the interior noise of a vehicle is reduced by reducing the pulsation noise of hydraulic fluid which is pressurized from an oil pump during steering and flows into a control valve to exert steering power The present invention relates to a pulsation noise reduction device of a power steering device that can reduce the noise.

In general, a vehicle is provided with a steering device that allows the driver to change the driving direction of the vehicle at any time during driving. The steering device is mounted to allow the driver to arbitrarily change the driving direction of the wheel. In order to transmit the operating force to each mechanism by operating the steering wheel, steering shaft, column, etc., the operating mechanism is increased by decelerating the rotation of the steering shaft, and the movement direction of the operating mechanism is changed and transmitted to the link mechanism. In order to transmit the gear mechanism and the movement of the gear mechanism to the front wheel and maintain the relation position of the left and right wheels correctly, a link mechanism composed of a pitman arm and a drag link, a knuckle arm and a tie rod is provided.

On the other hand, in the case of a large car or a vehicle using low pressure tires, since the grounding resistance of the front wheel is large, the steering force of the steering wheel becomes large and the quick steering operation is not possible. The same power steering device includes a power device composed of an oil pump for generating hydraulic pressure as a power source, a valve unit including a pressure control valve and a flow control valve, and a hydraulic power generated by the oil pump to generate a steering force. An operating device using a cylinder and a control device for opening and closing the flow path leading to the operation device and controlling the operation direction and operating state of the power cylinder by changing the flow path in accordance with the operation of the handle.

That is, as shown in FIG. 1, the general type power steering apparatus includes a steering shaft 2 having a steering handle 1 mounted on an upper end portion of the driver for steering operation, and the steering shaft 2. A steering column (3) fixed to the vehicle body by wrapping it externally, a control valve (4) mounted on the lower part of the steering shaft (2) to control the flow of hydraulic fluid during steering, and a lower side of the steering shaft (2). An operating cylinder (5) having a rack bar (not shown) engaged with a drive pinion part (not shown) provided at the tip and performing a linear motion according to its rotational movement, and connected to the engine via a crankshaft and a belt. Oil pump (6) which is operated by the power supply to supply the pressurized hydraulic oil to the control valve (4) when steering, the oil storage tank (7) storing a certain amount of hydraulic oil to supply the hydraulic oil to the oil pump (6) It consists of).

In addition, between the control valve (4), the oil pump (6) and the oil storage tank (7), a supply line (8) and a recovery line (9) for supplying and recovering hydraulic oil are respectively disposed. Tie rod 10 is provided at both end portions of (5) to be connected to the internal working piston and exposed to the outside so that the other end thereof is connected to the front wheel side knuckles to rotate the knuckle in the turning direction during steering.

Therefore, when steering, the oil pump 6 supplies the hydraulic oil pressurized to the control valve 4 through the supply line 8, and thus the control valve 4 is operated to reduce the operating force in the steering direction (5) ), The operation piston is pushed, and the movement of the operation cylinder (5) causes the tie rod 10 to rotate the knuckle to facilitate steering.

However, in the conventional power steering apparatus configured as described above, the oil is stored in the oil storage tank 7 and is pressurized by the operation of the oil pump 6 during steering to be supplied to the control valve 4 through the supply line 8. When the hydraulic oil passes through the supply line 8, it causes pulsation caused by a sudden change in the flow rate due to the pressurization of the oil pump 6, which causes noise. The pulsation of the operating oil causes noise in the supply line 8. Of course, there was a drawback to propagate the noise into the cabin.

Accordingly, the present invention has been made to solve the above disadvantages, it is possible to reduce the pulsation caused by the sudden flow rate change of the fluid on the supply line for supplying the hydraulic fluid pressurized from the oil pump in the power steering device to the control valve It is an object of the present invention to provide a pulsation noise reduction device of a power steering device which can reduce the noise level in a vehicle cabin by mounting means.

1 is a configuration diagram showing a power steering device of a conventional vehicle;

2 is a block diagram of a power steering apparatus having a pulsation noise reduction device according to the present invention;

3 is a cross-sectional view showing a state before operation of the pulsation noise reduction device which is the main part of the present invention;

4 is a cross-sectional view showing a state after the operation of FIG.

5 is a main part perspective view of FIG. 3;

6 is a front view of FIG. 5.

<Description of Symbols for Main Parts of Drawings>

1-steering wheel 2-steering shaft

3-steering column 4-control valve

5-operating cylinder 6-oil pump

7-Oil Storage Tank 8-Supply Line

9-Return Line 10-Tie Road

11-pulsation reduction means 12-housing

13-rod 14-attenuation plate member

15-tensile spring

The present invention for achieving the above object, the operating cylinder for hydraulically manipulating the movement of the tie rod to reduce the steering force during steering, and the control valve for supplying the hydraulic fluid appropriately for the movement of the operation cylinder And an oil pump for pressurizing the hydraulic oil supplied to the control valve, the power steering apparatus comprising: a pulsation reducing means for reducing pulsation of the hydraulic oil on a supply line for supplying the hydraulic oil pressurized from the oil pump to the control valve It is characterized by the excretion.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a block diagram of a power steering apparatus having a pulsation noise reduction device according to the present invention, Figure 3 is a cross-sectional view showing a pre-operational state of the pulsation noise reduction device that is the main part of the present invention, Figure 4 is the operation of Figure 3 Figure 5 is a cross-sectional view showing a state after, Figure 5 is a perspective view of Figure 3, Figure 6 is a front view of Figure 5, the same reference numerals will be given together with the same reference numerals as in Figure 1 showing a conventional power steering device. .

As shown in the drawing, a steering shaft 2 having a steering wheel 1 mounted to an upper end thereof, a steering column 3 for fixing the steering shaft 2 to a vehicle body, and the steering shaft 2 Control valve (4) mounted on the lower part of the control unit for controlling the flow of hydraulic oil during steering, and an operation cylinder (5) for linear movement according to the rotational movement of the steering shaft (2), the control valve (4) during steering An oil pump 6 for supplying pressurized hydraulic oil, an oil storage tank 7 for storing the hydraulic oil supplied to the oil pump 6, the control valve 4, an oil pump 6, and an oil storage tank ( 7) In the power steering device composed of a supply line (8) and a recovery line (9) disposed for the supply and recovery of the hydraulic oil between each, the hydraulic oil pressurized from the oil pump (6) control valve (4) On the supply line (8) to supply the gas to the low flow rate of the fluid generated from the rapid flow rate change of the fluid flowing Is the ripple reducing means 11 is configured so that the excretion.

That is, the pulsation reducing means 11 mounted on the supply line 8 includes a housing 12 in communication with it on the supply line 8, as shown in FIG. 3, and in the housing 12. Two damping plate members 14 fixed and disposed through the rod 13 inserted through the center to partition the inner space, so that the damping plate members 14 are elastically supported in the housing 12. It consists of a tension spring (15) connecting the one end of the rod (13) and the inner portion of the housing (12), respectively.

5 and 6, through holes 14a are formed in the housing 12 for the flow of the working oil in the housing 12, the through holes 14a. ) Are formed to shift each other so as to attenuate the pulsation of the working oil when the working oil flows.

In addition, the tension spring 15 for elastically supporting the damping plate member 14 is a control valve via a pulsation reducing means (11) mounted on the supply line 8, the hydraulic oil pressurized from the oil pump (6) ( 4) When supplied to the hydraulic fluid by moving the damping plate member 14 elastically in accordance with the discharge flow rate of the oil pump (6) discharged from the minimum pressure zero to the maximum pressure relief pressure in accordance with the steering conditions during steering It is possible to further reduce the pulsation of.

In the above, two damping plate members 14 are mounted on the rod 13 in the housing 12 of the pulsation reducing means 11 to reduce pulsation of the hydraulic oil. The number and position of the through holes 14a and the number of the through holes 14a formed therein can be appropriately adjusted for better reduction of pulsation, and the tension spring 15 elastically supporting the damping plate member 14. Of course, the spring stiffness can be properly adjusted according to the steering conditions.

Accordingly, in the power steering apparatus having the pulsation reducing means 11 configured as described above, as shown in FIG. 4, the hydraulic oil pressurized from the oil pump 6 passes through the supply pipe 8 and the control valve 4 as shown in FIG. 4. When it flows into the inside, the flow rate of the hydraulic oil discharged from the oil pump 6 is pushed out through the through holes (14a) formed by shifting the damping plate member 14 to the right to enter the control valve (4), The pulsation of the hydraulic fluid is attenuated and the noise caused by the pulsation of the fluid is reduced.

In other words, if the pulsation of the discharge flow rate according to the pressurization of the hydraulic fluid in the power steering device is effectively attenuated, the indoor noise level of the vehicle is also reduced. You can expect.

As described above, according to the pulsation noise reduction device of the power steering apparatus according to the present invention, the pulsation reduction means capable of reducing the pulsation of the hydraulic oil on the supply line for flowing the hydraulic oil pressurized from the oil pump to the control valve in the power steering apparatus By squeezing out, it is possible to reduce the pulsation of the fluid due to the pressure of the hydraulic fluid during steering to reduce the noise transmitted to the interior of the vehicle, thereby improving the merchandise of the vehicle, as well as the convenience of the occupant.

Claims (4)

Steering shaft (2) having the steering wheel (1) attached to the upper end, a steering column (3) for fixing the steering shaft (2) to the vehicle body, and a lower portion of the steering shaft (2) mounted to the operating oil during steering A control valve 4 for controlling the flow, an operation cylinder 5 for linear movement according to the rotational movement of the steering shaft 2, an oil pump for supplying pressurized hydraulic oil to the control valve 4 during steering ( 6), the oil storage tank (7) for storing the hydraulic oil supplied to the oil pump (6), the supply and recovery of the hydraulic oil between the control valve (4) and the oil pump (6) and the oil storage tank (7), respectively In the power steering device consisting of a supply line (8) and a recovery line (9) disposed for the On the supply line 8 for supplying the hydraulic oil pressurized from the oil pump 6 to the control valve 4, the pulsation reducing means 11 to reduce the pulsation of the fluid generated from the sudden flow rate change of the fluid flowing therein Pulsation noise reduction device of the power steering device characterized in that it is mounted. 2. The pulsation reducing means (11) according to claim 1, wherein the pulsation reducing means (11) is fixed to the housing (12) formed in communication with the supply pipe (8) through the rod (13) to partition the internal space in the housing (12). A plurality of damping plate members 14, a rod 13 for connecting the damping plate member 14 and a tension spring 15 which is installed between the housing 12 and elastically supports them. Pulsation noise reduction device of steering system. 3. The pulsation noise reduction of the power steering apparatus according to claim 2, wherein the damping plate member (14) is provided with a plurality of through holes (14a) arranged so as to be plural and displaced for the flow of the hydraulic oil in the housing (12). Device. 4. The pulsation reducing means (11) according to any one of claims 1 to 3, wherein the pulsation reducing means (11) has a suitable quantity and position of the attenuation plate member (14) and the number of through holes (14a) formed therein for better reduction of pulsation. It can be adjusted, the spring stiffness of the tension spring (15) for elastically supporting the damping plate member 14 is also characterized in that the pulsation noise reduction device of the power steering apparatus can be adjusted according to the steering conditions.