JPS6092971A - Power steering and reaction regulating valve - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reaction force regulating valve used in a par-no-steering and its side-war steering.

In general, the steering wheel of a vehicle has been designed to generate a reaction force in order to make the driver feel the weight of steering, that is, the steering resistance from the road surface.

However, if the magnitude of the reaction force is set small in advance, it becomes possible to steer with a small operating force when stopped or driving at low speeds, reducing steering fatigue, but when driving at high speeds, the response is too light. Steering tended to become unstable.

On the other hand, if the reaction force is set large in advance, stable steering becomes possible when driving at high speeds, but when the vehicle is stopped or driving at low speeds, the response is too heavy, which tends to increase steering fatigue.

In recent years, in order to avoid such inconveniences, shock steering systems have been proposed that change the reaction force according to the driving conditions, such as engine speed sensitive type or vehicle speed sensitive type. In these power steering systems, the range of change in the reaction force is narrow, so it is difficult to obtain the most suitable reaction force depending on the driving conditions of the vehicle. The means of change became complex and production costs tended to increase.

The purpose of this invention is to change the reaction force according to the driving conditions of the vehicle, and to obtain the most suitable reaction force for steering from a standstill to high-speed driving, thereby enabling safe and reliable steering. The goal is to provide power steering, which reduces steering fatigue.

Another object of the present invention is to adjust the flow rate of pressure oil flowing between a pair of communication ports as a variable throttle, and in particular, to adjust the flow rate of pressure oil flowing between the ports. It balances the pressure in the axial and radial directions within the bore, reduces the frictional resistance of the valve rotor, and also avoids deviation of the valve rotor, allowing smooth rotation and allowing the valve to rotate with extremely low power. The rotor can be rotated, and the sensitivity has been increased, the static and dynamic characteristics of the valve have been improved, and the accuracy of flow rate adjustment has been improved.
To provide a reaction force adjustment valve for use in power steering, which is most suitable for adjusting reaction force in power steering.

In order to solve these problems, the present invention has developed a control valve, a control valve, and a control valve equipped with a pair of rear axicon chambers on both sides of the oil pump, flow control valve, and control valve. wherein a reactor communication passage communicates the pair of reactors with each other, and a reaction force regulating valve is disposed in the reactor communication passage and is open to the valve-bore and the valve bore. A valve couping having a pair of communication ports, a valve rotor rotatably disposed in the valve bore so as to adjust the flow rate of pressure oil flowing between the communication ports, and within the valve bore, a pair of axial pressure chambers spaced at opposite ends of the valve rotor and formed within the valve bore to axially pressure equilibrate the valve rotor; a pair of radial pressure chambers in communication with each other to radially pressure equilibrate the valve rotor; and one of the radial pressure chambers in response to rotational movement of the valve rotor to one of the communication ports. 9 grooves formed in the valve rotor to enable communication, and the actuator further includes:
The reaction force adjustment valve is configured to be driven depending on the driving conditions of the vehicle.

Further, the reaction force adjustment valve of the present invention adapted to adjust the reaction force of power steering includes a valve casing having a valve bore and a pair of communication ports opened in the valve bore, and a valve casing having a valve bore and a pair of communication ports opened in the valve bore; A valve rotor rotatably disposed in the valve bore so as to adjust the flow rate of pressure oil flowing between the communication ports, and a valve rotor axially pressure balanced within the valve bore. and a pair of axial pressure chambers formed in the valve bore and cooperating with opposite ends of the valve rotor to bring the valve rotor into radial pressure equilibrium in the valve bore. a pair of radial pressure chambers communicated with each other and their communication, t?, in response to rotational movement of the valve rotor; The valve rotor is configured to include a throttle groove formed in the valve rotor so that one of the radial pressure chambers can communicate with one of the valve rotors.

Desired below are the power steering according to the present invention and the reaction force regulating valve used in the power steering.
For specific examples, please refer to the drawings.
A specific example 1 of the iR power steering of the present invention applied to an over-type trunk will be schematically shown, and 2 to 4
The figure shows a reaction force regulating valve 16 used in the power steering 10.

This e-war steering 10 is controlled by operating a steering wheel (not shown) to control the e-valve 13 (7), control the e-valve 13 (7), and control the self-spool 41.
The pressure oil flows from the oil pump 11 through the flow control valve 12 to the cylinder 14.
The power cylinder 14 is operated by connecting the power cylinder 14 to perform steering, and the reaction force generated during such steering is generated on both sides of the control valve valve 41. The reaction force is generated by pressure oil in the action chamber 53, 54, and the reaction force regulating valve 16 adjusts the pressure in the reaction chamber 53, 54 to change the reaction force.

That is, the power steering 10 uses oil.
Bond f 11 t, flow control r<ruf 1
2 (!: , A pair of reactor chambers 53゜54ヲ (i
The control valve 13 for tfL, the power cylinder 14, and the reactor control communication passage 15 that connects the reactor control chambers 53 and 54 with each other, the reaction force A regulating valve 16 disposed in the reactor control communication passage 15, and the The actuator 72 opens and closes the reaction force adjustment valve 16.

In addition, the reaction force adjustment valve 16, which is adapted to adjust the reaction force in the war steering 10, is a valve rotor for changing the flow rate of pressure oil flowing between a pair of communication IP-119 and IP-20. 21, and configured such that the valve rotor 21 is axially and radially pressure balanced within the rotor bore 18 to avoid offset 9 of the valve rotor 21 and to provide extremely smooth rotation. has been done.

Furthermore, to explain the reaction force adjustment valve 16 in detail, the reaction force adjustment valve 16 has a valve bore 18 and a valve bore 18 and a valve bore 18 and a valve bore 18.
A valve casing 17 having a pair of communication ports 19, 20 opening into the bore 18, and the communication ports 1-1.
A valve rotor 21 is rotatably disposed in the valve bore 18 so as to adjust the flow rate of pressure oil flowing between the valve gear 18 and the valve rotor 21. a pair of axial pressure chambers 25.2 formed in the valve bore 18, cooperating with opposite ends of the valve rotor 21, for pressure equalization in the directions;
6, and within its valve bore 18, its valve
A pair of radial pressure chambers 29.30 are in communication with each other so as to radially pressure balance the rotor 21, and one radial pressure chamber 29. A letter throttle groove 27 formed in the valve rotor 21 and a drive shaft 73 of the valve rotor 21 and the drive shaft 22 of the actuator 72 are connected to each other so as to enable the directional pressure chambers 29 to be connected to each other. Connect and those shirts 1-2
It is constructed with a clearance fit joint 76 that allows an eccentricity between the shafts of 2.73 mm.

The oil pump 11 is driven by an internal combustion engine (not shown) mounted on the cat-over type truck, and sucks up oil stored in an oil reservoir (not shown) to pump the internal combustion engine. It is constructed so that the amount of pressure oil discharged is approximately proportional to the rotational speed.

Since the oil pump 11 is constructed in the same manner as the oil pump 0 used in existing power steering systems, a description of its h'η configuration will be omitted.

Flow control valve 12 id, so (7) Pump 0 port 66 connected to the discharge side of the oil pump 11, control valve 12 connected to the supply port 32 side of the control valve 13, which will be described later. A casing comprising a port 67 and a casing port 68 connected to the suction side of the oil bomb 7'll, and an oil return control spool ( (not shown), adjusts the flow rate of the pressure oil sent to the seven-gastric pump port 66 side, sends a predetermined flow rate to the control valve port 67 side, and also sends the excess flow rate to the suction port 67 side.・The oil pump 11 from port 68
The oil reservoir is configured to be returned to the suction side of the oil reservoir (not shown).

9. The flow control valve 12 is constructed in the same manner as the flow control valve used in existing power steering systems, so a detailed explanation of its construction will be omitted.

The control valve 13 is connected to the spool chamber 31
(7) Control of flow control valve 12...Glub...t? -) 67 (supply hoard 32 connected to the spool chamber 31 of the
The spool chamber 31 is connected to the oil bomb fill.
A control bell casing 30 with a discharge port 33 and a power cylinder port 34, 35.36, connecting its supply port 32 to its discharge port 33 and a power cylinder port 34.35.36 to switch and connect,
A control spool 41 is arranged to be reciprocally slidable within the spool chamber 31, and a pair of reactor chambers 53 are formed within the spool chamber 31 on both sides of the control valve stool 410. It is composed of .54 and Yoshi.

Of course, in the spool chamber 31 there is a supply and a discharge of so; -1-32 and 33, linogs i'7jf 39 and 40 are formed, respectively.

i,, when the control ψ・group spool 41 is in the neutral position (1°■), the ring groove 3
Lands 42.45 are formed around both ends of the control spool 41, which is located outside the 9.40 fill.
Lands 43 and 44 are formed between them so as to face the ring grooves 39 and 40, respectively.

Of course, between those lands 42, 43, 44.45,
Spherical grooves 46, 47, 48 are formed which can be connected to the i9 cylinder ports 34, 35, 36, respectively.

The control valve spool 41 is located inside both ends of the sono control valve C spool 41.
A bore 49.50 extending along the axial direction and open at both ends is formed, and the bore 49.50
is connected to the stool groove 46. through the communication hole 51.52.
47, respectively.

Therefore, the grooves 46 and 47 are connected to the communication hole 5.
1, 52 and via bores 49.50 to the reactor chambers 53, 54, respectively.

The control valve spools 41 on the left and right slide back and forth in response to steering operations. One end of a shaft 71 is fixed at approximately the center of the control valve spool 41 on the left, and the shaft 71 The other end of 71 passes through the control valve casing 30 and is connected to a second steering shaft (not shown).

Supply of control valve 13 configured as described above; I? - A 2 is connected to the D control valve port 67 via the supply piping 69 to the flow 0 control valve 7'l 2 (D control valve port 67, and the small exhaust port 33
is connected to the Zakunocon side of the oil pump 7011 via the return pipe 70.

・G1 no・Cylinder 14id, -t control・
- Nokwar/ring with a 7 cylinder bore 58 integrally formed in the casing 30 of the group 13 and connected to the control .. power cylinder ports 34, 35, 36 of the group 13.・Casing and its 79-war 7-ring ports 34, 35, and 36
and a power piston 61 disposed in a reciprocating manner in the cylinder bore 58 so as to form a pair of correspondingly connected cylinder chambers 59 and 60 in the cylinder bore 58. , further conceptually explaining the output section, it consists of an operating rotor 2 whose one end is connected to the power piston 61 and whose other end extends outward through the power cylinder casing; A rod 63 is fixed to the power cylinder casing at a position opposite to the operating rod 62 and substantially coaxially with the operating rod 62 .

Of course, the power cylinder ports 34 and 35 of the control valve 13 are connected to the cylinder chamber 60 via the communication passages 55 and 56, and the power cylinder port 36 is connected to the communication passage 57. Through the cylinder chamber 59
are connected to each other.

Further, the tip of an operating rod 62 that is fixed to the power piston 61 and protrudes outside the power cylinder casing is attached to the shaft 7 of the cab-over type truck.
A frame (not shown) (attached to the
A rod 63 fixed to the power cylinder casing on the opposite side of the operating rod 62 is shown schematically representing the steering resistance on the tire side.

The Reaxilon communication passage 15 has a pair of control valve chambers 53 and 54 in its control valve 13.
are communicating with each other. That is, the Reak/Con communication passage 15 has one end connected to one Reakshilon chamber 53.
and the other end to port 38 of the other Reaxilon chamber 54, respectively.

In other words, the reaction force adjustment valve 16 adjusts the flow rate of the pressure oil flowing through the Reaxilon communication passage 15. It is arranged at a predetermined position in the reactor/con communication passage 15 so as to adjust the flow rate of pressure oil flowing from the reactor chamber 54 to one reactor chamber 53 and change the reaction force during steering.

The reaction force regulating valve 16 has a valve bore 18 and a pair of communication ports 19.2 opened to the valve bore 18.
to adjust the flow rate of pressurized oil flowing between the valve casing 17 having the
Its・Gurubu. A valve rotor 21 rotatably disposed in the bore 18 and cooperating with opposite ends of the valve rotor 21 to axially pressure balance the valve rotor 21 within the valve bore 18. , a pair of axial pressure chambers 25 formed within the valve bore 18 thereof.
．． 26 and a pair of radial pressure chambers 29.30 in communication with each other to radially pressure balance the valve rotor 21 within the valve bore 18; Accordingly, the valve rotor 21 is formed so as to be able to communicate the one radial pressure chamber 29 with the one communication hoard 19.
The throttle groove 27 and its valve rotor 21
The shaft 22 and the drive shaft 73 of the actuator 72 are connected to each other, and the shaft 22 and the drive shaft 73 are configured with a clearance fit joint 76 that allows eccentricity between the axes of the shafts 22 and 73.

The valve casing 17 has a valve bore 18, and a pair of communicating ports 19, 20 are each formed in the valve casing 17 in communication with the valve bore 18. . The communication ports 19 and 20 are formed in the valve casing 17 so as to be connected to approximately the center of the side surface of the valve bore 18, as can be understood from FIG. In addition, the communication port 20 is not located coaxially with the communication port 19, but is offset radially to one side so as to be substantially parallel to the communication port 19. .

A sonopulp rotor 21 is rotatably disposed in its valve bore 18 such that axial pressure chambers 25, 26 are formed above and below the valve bore 18, respectively. That is, the valve rotor 21
is pressure-balanced in the axial direction by the pressure in its axial pressure chambers 25 and 26.

Of course, both end faces of the valve rotor 21 are provided with abutting surfaces 74,75 each having an area much smaller than the area of the upper and lower ends of the valve bore 18, but these abutting surfaces 74,75 are The axial movement of the valve rotor 21 whose pressure is balanced in the axial direction is restricted.

Therefore, the valve rotor 21 is connected to the valve bore 1
The pressure is balanced in the axial direction within 8 Hq.
Since the contact area between the valve rotor 75 and the upper and lower end surfaces of the valve bore 18 is extremely small, the valve rotor 21 rotates extremely smoothly.

It is an incompressible fluid in its axial pressure chamber 25.26.
For example, it is also possible to fill the valve rotor 21 with oil and to pressure balance the valve rotor 21 with the oil in the axial pressure chamber 25,26. In that case, if the axial movement of the valve rotor 21 is restricted by oil as an incompressible fluid, the above-mentioned per 1i74.75 can be omitted and the valve rotor 21 and the valve bore 18 The contact area of the valve rotor 21 can be further reduced, and the rotation of the valve rotor 21 can be made even smoother.

The pair of radial pressure chambers 29.30 have a pair of notches 23.24 at predetermined positions on the outer peripheral surface of the valve rotor 21.
, and are formed in cooperation with the inner periphery of the valve bore 18 so as to be oriented in the λ1 direction within the valve bore 18.

Further, the pair of radial pressure chambers 29,30 are communicated with each other by a continuous passageway 28 formed radially through the valve rotor 21.

Further, on the outer peripheral surface of the valve rotor 21, a throttle groove 27 is formed which is connected to one of the notches 23, in other words, which is connected to one of the radial pressure chambers 29.

Of course, FIGS. 2 and 3 show a state in which the communication ports 19 and 20 of the reaction force regulating valve 16 are closed.
In such a state, within a predetermined range of rotation of the valve rotor 21, the communication port 20 is always in communication with the radial pressure chamber 30.

Therefore, in the reaction force regulating valve 16 shown in FIG. 3, if the valve rotor 21 is rotated to the right, the throttle groove 27 will be in communication with the communication port 19, and as a result, the communication port 19 will be in communication with the communication port 19. ) 1.9.

20 are interconnected.

Further, since the throttle groove 27 is designed so that the groove becomes deeper as it approaches the notch 23 side, the throttle groove 27 and its communication port 19 are connected in accordance with the rotation of the valve rotor 21. The area of the communication passage is changed, that is, the amount of restriction between the communication ports 19 and 20 is changed.

Further, the valve rotor 21 includes a valve shaft 22 extending downward at a lower end surface, that is, a position on the contact surface 75 side.
The valve shaft 22 is passed through the valve casing 17 such that the two ends protrude outside the valve casing 17.

The actuator 72 is a stenobifug motor connected to the end of the valve shaft 22 via a slip joint 76 so as to rotate the valve rotor 21, and rotates in accordance with the traveling speed of the cab-over type truck. It is configured to change the flow rate of pressure oil flowing into the communication ports 1-19 and 20 of the reaction force adjustment valve 1G.

That is, the actuator 72 is connected to the vehicle speed sensor (
(not shown), and is configured to rotate the valve rotor 21 in response to an output signal from the vehicle speed sensor. Of course, the actuator 7
In the electric circuit No. 2, an amplifier (not shown) is arranged between the actuator 72 and the vehicle speed sensor, and the output signal from the vehicle speed sensor is amplified by the amblifier, and the amplified output signal is It is desirable that the actuator 72 is configured to be driven one time depending on the signal.

Further, the actuator 72 includes various sensors such as a vehicle speed sensor and an engine rotation speed sensor, input and output circuits, a memory circuit, and an arithmetic circuit.

When used in combination with a control unit (not shown) from the control circuit r'% source circuit, etc., to achieve more sophisticated control of the reaction force regulating valve 16, the loose fit joint 76 is used in conjunction with a control unit (not shown) from the control circuit r'% source circuit, etc. The drive shaft 73 is connected to the valve shaft 22 of the valve rotor 21.
Moreover, eccentricity between the shafts of the drive shaft 73 and the valve shaft 22 is allowed.

That is, the loose fit joint 76 is connected to the protrusion 7 formed on the end of the valve/gift 22 of the valve rotor 21.
7, and a fitting groove 78 formed at the end of the drive shaft 73 of the actuator 72 so that the projection 77 is fitted with a predetermined play.

Therefore, the width of the protrusion 77 and the length along the radial direction of the valve shaft 22 at the protrusion 77 are:
The width of the fitting groove 78 and the length of the drive shaft 73 in the fitting groove 78 in the radial direction are made shorter, and in a state where the protrusion 77 is fitted into the fitting groove 78, a predetermined Play occurs in the drive shaft 73 and the valve shaft 22. !
: The actuator 7 is
+t'7 is configured to ensure that the power of 2 is transmitted to the valve shaft 22.

Next, we will discuss the running of the cab-over type trunk equipped with the power steering 10 including the North/Bo reaction force A9F valve 16.
- When the rank travels at low speed, the actuator 72 is driven by the output signal from the vehicle speed sensor, and the reaction force adjustment valve 1 is activated.
6 valve rotor 21 rotates, and a pair of communication ports 1
9.20 are not extremely restricted and are communicated with each other via the throttle groove 27, the pair of radial pressure chambers 29.30, and the communication passage 28.

Under such conditions, the flow rate of the pressure oil U supplied from the oil pump 0i1 is adjusted by the Sufu control valve 12, and a predetermined flow rate of pressure oil is sent to the supply date 32 of the control valve 13. It will be done.

The pressure oil sent to the supply port 32 is
When the valve valve 41 is in the neutral position, the control valve A is returned to the pump side of the oil pump 11 through the discharge port 33.
When the lever 41 is slid to either side by the steerer, depending on the sliding direction, the pressure oil is transferred to either one of the cylinder chambers 59, 60 of the power cylinder 14, Then, it is sent to one of the reactor chambers 53 and 54.

fll Eva, SO (D control valve control spool 4
1 is slid to the right in FIG.
Power cylinder port 3 via spool groove 47 of
6, pressure oil is sent to the cylinder chamber 59 of the e-war cylinder 14, and the power piston 61 is moved to the left in FIG. 1, in other words, the power cylinder 14 is moved to the right.

When pressure oil is supplied in this way, a part of the pressure oil is
It is sent to the reactor chamber 54 via the communication hole 52 and bore 50.

The reaction force caused by such steering is given by the pressure in the rear suspension chamber 54, but as mentioned above, when driving at low speed, the reaction force is applied by the pair of communication ports 1 of the reaction force adjustment valve 16.
- I 9 and 20 are communicated with each other with a wide passage cross-sectional area without being extremely constricted, so the pressure oil in the reactor chamber 54 is sent to the other reactor chamber 53.

Of course, if the sonocontrol valve stool 41 is slid as described above, the discharge port 33 will be connected to the valve seat 46, so that the rear chamber 5 will be connected to the exhaust port 33.
The pressure oil in 3 is returned to the oil pump 011's first rule.

Therefore, the pressure oil in the reactor chamber 54,
'c' control does not create a large resistance to the sliding of the roll valve spool 41, and steering at low speeds is performed with small force.

If the control spool 41 is slid to the left side as shown in Fig. 1, the supply port 32 is in the spool groove 48, and the discharge port 33 is in the spool ri
47, respectively, and pressure oil is supplied to the cylinder 14117)-7 through the communication passage 55, 56 to the ring chamber 6.
0 and the reactor chamber 53, respectively, and the blower piston 61 is moved to the right in FIG. 1, that is, the power cylinder 14 is moved to the left.

Contrary to the case described above, the pressure oil in the reactor chamber 53 passes through the reactor communication passage 15 and is sent to the reactor chamber 54 without being extremely throttled by the reaction force adjustment valve 16. The oil in the chamber 54 passes through the bore 50, the communication hole 52, and is returned to the suction side of the oil pump 11 through the exhaust port 33.

Therefore, as in the case described above, the pressure oil in the reactor chamber 53 does not provide a large resistance to the sliding of the control valve spool 41, and steering at low speeds can be performed with a small operating force. Ru.

Of course, when the cab-over type truck is steered while stopped, the traveling speed is zero, and the cross-sectional area of the passage between the connection ports 19 and 20 in the reaction force adjustment valve 16 is widened to the maximum. , the mutual pressure difference between the reactor chambers 53 and 54 becomes extremely small, and it becomes possible to move in a fixed position, move one width closer, and turn back with an extremely small operating force.

Furthermore, when the cab-over type truck travels at high speed, the actuator 72 is driven by the output signal from the vehicle speed sensor, and the valve rotor 21 of the reaction force adjustment valve 16 is driven.
rotates in the opposite direction to that described above, the communication port 19 is squeezed into its valve rotor 21, and the passage 11;
The area of part i is narrowed.

As in the case described above, if the control groove spool 41 is slid to either side, the cylinder chamber 59.
Pressure oil is sent to either side of the power piston 6
1 is slid, and a part of the pressure oil is sent to either of the reactor chambers 53 and 54, but the communication ports 19 and 20 of the reaction force adjustment valve 16 are narrowed, and the passage cross-sectional area is reduced. Since it is narrowed, the pressure drop caused by the reaction force adjustment valve 16 becomes large, and the left and right reactor chambers 53.
The pressure difference within the control valve spool 41 becomes large, creating a large resistance to the sliding movement of the control valve spool 41.
Relatively large operating force is required for steering when driving at high speeds, improving driving stability.

As described above, by rotating the valve rotor 21 of the reaction force adjustment valve 16, a reaction force most suitable for the driving conditions of the cab-over type truck can be obtained, but the axial pressure chambers 25, 26 As a result, the pressure of the valve coater 21 is balanced in the axial direction within the valve gear 18, and the contact area on the upper and lower end surfaces of the valve rotor 21 is extremely small, so that the frictional resistance of the valve rotor 21 is reduced. As a result, the valve coater 21 can be rotated with extremely small power. In other words, the actuator 72 that rotates the valve rotor 21 can be made smaller. becomes possible.

Further, the valve rotor 21 is cooperated with the inner peripheral surface of the valve bore 18 to form a pair of radial pressure chambers 29.
．． The pressure chamber 30 is provided with a pair of notches 23 and 24 each forming a valve rotor 30, and the notches 23 and 24 are connected to each other through a communication passage 28, and in a predetermined rotation range of the valve rotor 21, the pressure chamber 30 One side contact port 20
Since the rotor 21 is rotated slightly, the aperture groove 27 is connected to the communication port 1.
9, substantially the same pressure is applied to each of its radial pressure chambers 29, 30, in other words, if the valve rotor 21 is connected to its valve der 18.
radially pressure balanced within the valve rotor 21
Shifting of the valve rotor 21 is avoided, and the rotation of the valve rotor 21 is made extremely smooth.

Also, the valve shaft 22 of the valve rotor 21
is connected to the drive shaft 73 of the actuator 72 by a loose fitting joint 76 that allows eccentricity between the shafts, so that the power of the actuator 72 is reliably transmitted to the valve rotor 21, and Due to a few variations in the actuator 72, phase is absorbed by the loose fit joint 76 between the valve rotor 21 and the actuator 72.

Therefore, when installing the actuator 72, the actuator 72 can be easily installed without requiring high precision, and the actuator 72 can be easily installed.
By driving the valve rotor 21, the valve rotor 21 is appropriately rotated, and the reaction force during steering is properly adjusted.

According to the above invention, there is provided a valve casing having a valve gear and a pair of communication ports opened in the valve bore, and a valve gear configured to adjust the flow rate of pressurized oil flowing between the communication ports. - a valve rotor rotatably disposed on a gear and cooperating with opposite ends of the valve rotor to axially pressure balance the valve rotor within the valve bore; a pair of axial pressure chambers formed within the valve bore; and a pair of radial pressure chambers communicated with each other within the valve gear to radially pressure equilibrate the valve rotor. , so contact them according to the rotational movement of the valve rotor? - a throttle groove formed in the valve rotor so as to enable one of the radial pressure chambers to communicate with one of the valve rotors; Since the pressure is balanced in the axial and radial directions within the valve, the valve rotor is prevented from shifting, rotation is extremely smooth, and the valve rotor can be rotated with a small amount of power. Furthermore, the sensitivity has been increased, the dynamic and static characteristics of the valve have been improved, and the accuracy of flow rate adjustment has been improved, making it the most suitable reaction force adjustment valve for use in steering. , becomes extremely practical.

Furthermore, the power steering of the present invention, which includes the reaction force adjustment valve, is equipped with an oil pump, a flow control valve, etc.
Control valve, control...The basic configuration is a control valve with a pair of rear auxiliary control valves and a power cylinder on both sides of the valve spool, and a rear axial control passage is connected to the pair of rear axial control valves and a power cylinder.
and the reaction force adjustment valve described above is provided in the reaction communication passage, and further, the actuator rotates the valve rotor of the reaction force adjustment valve according to the driving conditions of the vehicle. As a result, the reaction force when steering changes depending on the driving conditions of the vehicle, and moreover, the reaction force most suitable for steering in trenches, from when stopped to when driving at high speed, is obtained, ensuring safe and reliable steering. In addition, the fatigue caused by steering is reduced, making it extremely practical.

As mentioned above, from the specific examples of this invention described with reference to the drawings, various design modifications and changes can be easily made by those who have ordinary knowledge in the technical field to which this invention pertains. Furthermore, the structure of this invention can be easily replaced with an embodiment essentially the same as this invention that satisfies essentially the same problems as that invention and achieves the same effects as this invention. I guess it will happen.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing a specific example of the power steering of the present invention applied to a cab-over type truck;
The figure is a vertical cross-sectional view showing a specific example of the reaction force regulating valve of the present invention used in the power steering shown in FIG. 1, and FIG. 'i Valve adjustment 3
- cross-sectional view taken along line 3;
War steering, oil,
Pon 70.12...Flow control pulp,
13... Con l-roll pulp, 14... Power cylinder, 15... React 7 con communication passage, 16...
・Reaction force adjustment valve, 17 ・Pulp cushing, 18...
Rotor bore, 19.20...Communication port, 21...
Pulp rotor, 23, 24, notch, 25.26
...Axis direction pressure chamber, 27... Throttle groove, 28... Communication path, 29.30... Radial direction pressure chamber, 72... Actuator. Enter/ Zuo 2I27 Iroo 4 Zuo 3 (27 Δ

Claims (2)

[Claims] (1) In a vehicle that is steered by a power cylinder and a control valve with a pair of rear axle chambers on both sides of the oil pump, flow control palft, and control valve snowboard, the rear axicon communication passage is connected to the pair of rear axle chambers. communicating the conchampers with each other, and a reaction force regulating valve being disposed in the reactor communicating passage and communicating therewith with a valve casing having a valve bore and a pair of communicating dates opening into the valve bore. To adjust the flow rate of pressure oil flowing between ports,
a valve rotor rotatably disposed on the valve gear and cooperating with opposite ends of the valve rotor to axially pressure balance the valve rotor within the valve bore; a pair of axial pressure chambers formed within the valve bore; a pair of radial pressure chambers in communication with each other to radially pressure equilibrate the valve rotor within the valve bore; a throttle groove formed in the valve rotor to allow one of the radial pressure chambers to communicate with one of the communication ports in response to rotational movement of the valve rotor; A power steering system characterized by driving a reaction force adjustment valve according to vehicle driving conditions. (2) a valve casing having a valve bore and a pair of communication ports opened in the valve bore; and a valve casing having a rotatable structure in the valve bore so as to adjust the flow rate of pressurized oil flowing between the communication ports. The valves located
a rotor; a pair of rotors formed in the rev bore and cooperated with opposite ends of the valve rotor to axially pressure equilibrate the valve rotor within the valve bore; In the axial pressure chamber and its valve bore,
a pair of radial pressure chambers in communication with each other so as to radially pressure equilibrate the valve rotor; and one of the radial pressure chambers in response to rotational movement of the valve rotor to one of the communication ports. Reaction force regulating valve used in power steering, which includes a throttle groove formed in the rep rotor so as to enable communication between the two.