JPS6092972A - Power steering and reaction regulating valve - Google Patents

Abstract

PURPOSE:To achieve highly accurate reaction regulation by communicating the reaction chambers at the opposite sides of spool of control valve for exchanging the flow of operating oil through a reaction regulating valve while making the valve rotor to be pressure balanced radially rotatable through slotted joint. CONSTITUTION:A control valve 13 having a pair of reaction chambers 53, 54 at the opposite sides of spool 41 is provided in the hydraulic circuit of power steering. A path 15 communicating between both chambers 53, 54 is provided and a reaction regulating valve 16 is placed in said path 15. Said valve is constructed by containing a valve rotor 21 having a restriction groove 27 for enabling communication between ports 19, 20 formed in the casing 17 rotatably in the rotor bore 18 of valve casing 17. The valve rotor 21 is pressure balanced radially by the pressure in radial pressure chambers 29, 30 to be communicated each other and rotated by an actuator 72 to be controlled in accordance to the car speed through slotted joint 76.

Description

[Detailed Description of the Invention] This invention relates to a power steering and its power steering system.
This invention relates to a reaction force adjustment valve used in steering.

In general, the power steering system 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 will be possible to steer with a small operating force when stopped or driving at low speeds, reducing steering fatigue, but the response will be too light when driving at high speeds. , the 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 overcome such inconveniences, steering systems that change the reaction force according to driving conditions, such as engine speed-sensitive or vehicle speed-sensitive types, have been proposed. However, 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 to change this tended to become more complex and production costs higher.

The purpose of this invention is to change the reaction force according to the running conditions of the vehicle, and to obtain the reaction force most suitable for steering from a stop to a high-speed drive, thereby enabling safe and reliable steering. The goal is to provide 1-no-steering, which reduces steering fatigue.

Another object of the invention is to provide a pair of contacts as variable apertures;
A valve rotor for adjusting the flow rate of pressure oil flowing between IP-) and, in particular, adjusting the flow rate of pressure oil flowing between IP-j'; It balances the pressure, avoids the bias of the valve rotor and makes it rotate smoothly, rotates the valve rotor with extremely low power, and increases the sensitivity and improves the static and dynamic characteristics of the valve. , improves the accuracy of flow rate adjustment, and also facilitates the connection between the valve rotor and the actuator that rotates the valve rotor, and improves the connection between the valve rotor's valve shaft and the actuator's drive shirt). Even if the actuator and the valve rotor are not coaxially positioned and are misaligned, the power of the actuator is properly transmitted to the valve rotor, making it most suitable for adjusting the reaction force in the front steering. The purpose of the present invention is to provide a reaction force regulating valve used in power steering.

In order to solve these problems, the power steering system of the present invention is equipped with an oil pump, a flow control valve, a pair of rear axicon chambers on both sides of the control valve control spool, and a flow control valve. a reactor communication passage communicates the pair of reactor chambers with each other, and a reaction force regulating valve is disposed in the reactor communication passage and is opened to the valve bore and the valve bore. Valve with a pair of communication ports
A valve rotor rotatably disposed in the rev bore of the casing and the valve rotor to adjust the flow rate of pressurized oil flowing between the connecting hoards, an actuator that drives the valve rotor, and the valve. a pair of radial pressure chambers in communication with each other to radially pressure balance the valve rotor within the bore;
<) A throttle groove formed in the valve rotor so as to enable one of the radial pressure chambers to communicate with one of the communication ports in response to rotational movement of the rev rotor;
The valve shaft of the valve rotor and the drive shaft of the actuator are connected to each other, and the structure includes a clearance fit joint that allows eccentricity between the axes of these shafts.

Further, the reaction force adjusting valve of the present invention adapted to adjust the reaction force of the steering wheel includes a valve casing having a valve bore and a pair of communication ports opened in the valve bore. , those contacts, I? −
A valve rotor rotatably disposed on the valve gear so as to adjust the flow rate of pressurized oil flowing between the valve gears, an actuator that drives the valve rotor, and an actuator that drives the valve rotor within the valve bore.・A pair of radial pressure chambers communicated with each other so as to pressure balance the rotor in the radial direction, and the valve according to the rotational movement of the rotor.
A throttle groove formed in the valve rotor and a valve shaft of the valve rotor and a drive shaft of the actuator are connected to each other so as to allow one of the radial pressure chambers to communicate with one of the communication ports. The structure includes a clearance fit joint that connects the shafts and allows eccentricity between the shafts.

Hereinafter, preferred specific examples of a power steering system according to the present invention and a reaction force regulating valve used in the power steering system will be described with reference to the drawings.

FIG. 1 schematically shows a concrete example 10 of the power steering of the present invention applied to a cab-over type truck, and FIGS. 2-4 show reaction force adjustment used in the power steering 10. Valve 16 is shown.

This power steering 10 slides a control valve spool 41 of a control fist pulp 13 by operating a steering wheel (not shown), and supplies pressurized oil from an oil pump 11 through a flow control valve 12. It is switched and connected to the power cylinder 14 to operate the power cylinder 14 and perform steering, and the reaction force when performing such steering is formed on both sides of the control valve spool 41. The reaction force is generated by the pressure oil in the action chamber 53.54, and the reaction force regulating valve 16 is configured to adjust the pressure in the reaction chamber 53.54 to change the reaction force.

In other words, is the PI power steering 10 an oil fist? 011, 70--a control valve 12, a control valve 13 with a pair of reactor chambers 53, 54 on either side of the control valve spool 41, a nozzle cylinder 14, and its reactor chambers. 53 and 54, a reaction force adjustment valve 16 disposed in the reaction force adjustment valve 16, and an actuator 72 that opens and closes the reaction force adjustment valve 16.

The reaction force adjustment valve 16, which is suitable for adjusting the reaction force in the power steering 10, is a valve rotor for changing the flow rate of pressure oil between a pair of connections, 1F-19.20. 21, the valve rotor 21 is radially pressure balanced within the rotor bore 18 to avoid offsetting of the valve rotor 21 and smooth rotation; The valve shaft 22 and the drive shaft 73 of the actuator 72 are connected by a clearance fit joint 76 that allows for eccentricity between the shafts, reducing the accuracy required for mounting the actuator 72, and making it possible to connect the valve rotor 21. It is configured to rotate properly.

Furthermore, to explain the reaction force adjustment valve 16 in detail, the reaction force adjustment valve 16 has a valve bore 18 and a sonopulp valve.
A pair of communication holes 1-19, 2 opened in the bore 18
0 and their communication z-
In order to adjust the flow rate of pressure oil flowing between x9 and x2o,
A valve rotatably disposed in the valve bore 18.
A rotor 21 is formed in the valve bore 18 in cooperation with opposite ends of the valve rotor 21 to axially pressure balance the nokulp rotor 21 within the valve bore 18. A pair of axial pressure chambers 25
．． 26 , a pair of radial pressure chambers 29 , 30 in communication with each other to radially pressure balance the valve rotor 21 within the valve gear 18 , and rotational movement of the valve rotor 21 . The valve rotor 21 is formed to allow one radial pressure chamber 29 to communicate with the one communication port 19 according to an it restriction? jli 27, etc., a groove fit joint 76 which connects the valve shaft 22 of the valve rotor 21 and the drive shaft 73 of the actuator 72 to each other and allows eccentricity between the shafts 22 and 73. It is composed of

The oil pump 011 is driven by an internal combustion engine (not shown) mounted on the cab-over type truck, and sucks up oil accumulated in an oil reservoir (not shown) to pump the internal combustion engine. It is configured so that the amount of pressure oil discharged is approximately proportional to the rotational speed.

The oil pump 11 is constructed similarly to the oil pump used for existing engine and war steering, so a description of its construction will be omitted.

Flow control valve 12 c,'c(7) Pump connected to the discharge side of oil pump 11...]e
-) fi6, a control valve connected to the supply port 32 side of the control valve 13 described later, t
? - a drawer, and a casing provided with a suction valve 68 connected to the suction side of the oil pump 11, and an oil return control valve 0- disposed in the casing so as to be able to reciprocate.
(f in the figure), etc., and its pump 0 and port 6
Adjust the flow rate of the pressure oil sent to the 6 side, send a predetermined flow rate to the control valve port 67 side, and
It is configured to return surplus flow from the suction, N-Toro 8 to the suction side of the oil pump 11, i.e. to the oil reservoir (not shown) side.

Sonoflow Control Valve 12i1: Since it is configured similarly to the flow control valve used in existing power steering, a detailed explanation of its configuration will be omitted.

Control valve 13 is Sugeru f Yanba 31
, connect the control valve port 67 side of the SonoFlow control valve 12 to its spool chamber 3.
a control valve casing 30 with a supply port 32 connecting its spool O-chamber 31 to the suction side of its oil pump 11; and a discharge port 33 connecting its spool O-chamber 31 to the suction side of its oil pump 11; , its supply port 32 and its discharge, I?
-to3B, yohi, /'wa cylinder...t? -)3
4.35.36, a control valve spool 41 reciprocally slidably disposed within its 7 pools and 9 yambas 31, and within its spool chamber 31, its control valve spool; 41
a pair of glue action chambers 53 formed on opposite sides of the
．． It is composed of 54 parts.

Of course, in the spool chamber 31 there is a
A ring '11139.40 is formed respectively.

When the sonocontrol valve spool 41 is in the neutral position, there are lands 42.45 around both ends of the control valve spool 41 located outside the ring groove 39.40. A ring groove 39 is formed between the lands 42 and 45, respectively.
．． Lands 43 and 44 are formed to face each other.

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

Inside both ends of the sonocontrol valve spool 41 are the control valve spools 4.
1 are formed with bores 49.50 extending along the axial direction and open at both ends, and the bores 49.5
0 is connected to the spool groove 46 through the communication hole 51.52.
．． 47, respectively.

Therefore, the spool groove 46, 47 is connected to the communication hole 51.
, 52 and via bores 49.50 to the reactor chambers 53, 54, respectively.

'! fc, 'c (7) The control valve stool 41 does not slide back and forth in response to steering operation;! :
One end of a shaft 71 is fixed to a substantially central position of the control valve e spool 41 of rfr)jr,'-'f:, and the other end of the shaft 71 passes through the control valve casing 3o. and is connected to a steering shaft (not shown).

Supply of control valve 13 configured as described above=I? -) 32 is connected to the flow via the supply piping 69.
It is connected to the control H/L7 port 67 of the control 0 valve 12, and the discharge date 33 is connected to the Zakuncon side of the oil bomb f11 via the return pipe 7o.

The power cylinder 14 has its control valve 1
The power cylinder port 3 of the control valve 13 is integrally formed in the casing 3o of
4, 35, 36, and a pair of 7-ring chambers 59, 60 correspondingly connected to its power cylinder ports 34, 35, and 36. That cylinder
the cylinder bore 58 so as to form within the bore 58;
A blower piston 61 is arranged so as to be able to slide back and forth within the
To further explain the output part conceptually,
An operating rod 62 whose one end is connected to the power piston 61 and whose other end protrudes outward through the power cylinder casing; It consists of a lower drawer 3 fixed to the blower, cylinder, and casing almost coaxially.

Of course, the 7F war cylinder ports 34 and 35 of the control valve 13 are connected to the cylinder chamber 6o through the communication passages 55 and 56, and the war cylinder ports 36 and 36 are connected to the cylinder chamber 6o through the communication passages 57. That cylinder chamber 59
are connected to each other.

Further, the tip of an operating rod 62 fixed to the R-war piston 61 and protruding to the outside of the power cylinder casing is connected to the shaft 7 of the cab-over type truck.
- It is attached to the frame (not shown) side, but the power, 7 cylinder,
The rod 63 side fixed to the casing is shown to schematically represent the steering resistance on the tire side.

The reactor control communication passage 15 has a pair of glue action chambers 53 and 54 in its control valve 13.
I am contacting you. That is, the reactor/con communication passage 15 has one end connected to one reactor/con chamber 53.
z-) 37 and the other end is connected to the port 38 of the other reactor chamber 54, respectively.

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

The reaction force regulating valve 16 has a valve bore 18 and a pair of communication holes 19 and 2 opened in the valve bore 18.
0 to adjust the flow rate of pressure oil flowing between the valve casing 17 and the communication ports 19 and 20,
A valve rotatably disposed in the valve bore 18.
to axially pressure balance the valve rotor 21 within the rotor 21 and its valve bore 18;
A pair of axial pressures p25 .cooperated with opposite ends of the valve rotor 21 and formed within the valve bore 18 .
2g and a pair of radial pressure chambers 29.30 in communication with each other so as to radially pressure equilibrate the valve rotor 21 within the valve bore 18 and to the rotational movement of the valve rotor 21. Accordingly, a throttle groove 27 is formed in the valve rotor 21 so that the one radial pressure chamber 29 can be communicated with the one communication hole 19, ' Connecting the drive shaft 73 of the foot 22 and its actuator 72 to each other, and
It is constructed with a one-way fit joint 76 that allows an eccentricity between the shafts of 22.73 mm.

The valve casing 17 has a valve bore 18, and a pair of communication ports 19, 20 are formed in the valve casing 17, respectively, so as to communicate with the valve bore 18. There is. The communication ports 1-19, 20 are connected to the valve bore 18 at approximately the center of the side surface thereof.
As can be seen from FIG. 3, the communication ports 20 are respectively formed in the casing 17,
I? -) without being located coaxially with respect to 19;
Make the contact = Jr-) almost parallel to 19,
It is radially offset to one side.

The valve rotor 21 is rotatably arranged in the 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
The pressure in the axial pressure chambers 25 and 26 provides pressure balance in the axial direction.

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
8, the pressure is balanced in the axial direction, and its roaring surface 74
．． Since the contact area between the valve rotor 75 and the upper and lower end surfaces of the parvoo bore 18 is extremely small, the valve rotor 21 rotates extremely smoothly.

In addition, an incompressible fluid is contained in the 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 valve rotor 21 is covered with oil as an incompressible fluid and its axial movement is restricted, the above-mentioned abutting surfaces 74 and 75 can be omitted and the valve rotor 21 and its valve By further reducing the contact area with the bore 18, the valve rotor 21 can rotate even more smoothly.

The pair of radial pressure chambers 29 and 30 have a pair of notches 23 and 24 at predetermined positions on the outer peripheral surface of the valve rotor 21.
By forming the grooves, the grooves are formed so as to cooperate with the inner circumferential surface of the groove bore 18 so as to face each other within the groove bore 18.

The pair of radial pressure chambers 29 and 30 are connected to each other by a communication passage 28 formed by penetrating the valve rotor 21 in the radial direction. is connected to one notch 23, in other words, a restricting groove 27 is formed which is connected to one radial pressure chamber 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 its valve rotor 21 is rotated to the right, its throttle groove 27 will be in communication with its communication port 19; 19.20 will be mutually communicated.

Unfortunately, the depth of the throttle groove 27 becomes deeper as it approaches the notch 23 side, so that the throttle groove 27 becomes deeper as the valve rotor 21 rotates.
The area of the communication passage between the communication port 19 and the communication port 19 can be changed, that is, the amount of constriction between the communication ports 19 and 20 can be changed.

Further, the valve rotor 21 is provided with a valve shaft 22 extending downward at a lower end surface, that is, at a position on the side surface 75, and the valve shaft I.
The valve shaft 22 passes through the valve gauging 17 such that the end 22 projects outside the valve casing 17.

The actuator 72 is a stepping 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. , and is configured to change the flow rate of pressure oil flowing into the communication ports 1-19, 20 of the reaction force adjustment valve 16.

That is, the actuator 72 is electrically connected to a 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 72
In the electric circuit, an amplifier 0 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 amplifier, and the amplified output signal is It is desirable that the actuator 72 be configured to be driven in accordance with the time.

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.

It is also possible to use it in combination with a control unit (not shown) consisting of a control circuit, a power supply circuit, etc., and to control the reaction force regulating valve 16 at a higher level.

A loose fit joint 76 connects the drive shaft 73 of the actuator 72 to the valve shaft 22 of the valve rotor 21, and also prevents eccentricity between the drive shaft 73 and the valve shaft 22. It is allowed.

That is, the loose fit joint 76 is connected to the projection 7 formed on the end of the valve shaft 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 protrusion 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 along the radial direction of the drive shaft 73 in the fitting groove 78 are also shortened, and when the protrusion 77 is fitted in the fitting groove 78, a predetermined position is set. The drive shaft 73 is configured to generate a play, and to compensate for the eccentricity between the shafts of the drive shaft 73 and the valve shaft 22 by 1/1, thereby reliably transmitting the power of the actuator 72 to the valve shaft 22. There is.

Next, the /F
To describe the running of a cab-over type truck equipped with flow steering 10, when the cab-over type truck is traveling at low speed, the actuator 72 is driven by the output signal from the vehicle speed sensor, and the reaction force adjustment valve 16 is driven.
The valve rotor 21 rotates, and a pair of communication ports) 19
．． 20 is not narrowed down to an extreme extent, and the groove 27. A pair of radial pressure chambers 29 and 30 are in communication with each other via a communication passage .

In such a state, the flow rate of the pressure oil supplied from the oil pump 11 is adjusted by the flow control valve 12, and a predetermined flow rate of pressure oil is sent to the supply port 32 of the control valve 13. .

The pressure oil sent to the supply port 32 is
When the valve spool 41 is in the neutral position, the control valve spool 41 is returned to the suction side of the oil pump 11 through the discharge port 33, but the control valve spool 41 can be moved to either side by steering operation. When the power cylinder 14 is slid, the pressure oil flows into either the ring chamber 59 or 60 of the power cylinder 14, depending on the direction of the slide.
Then, it is sent to either one of the reactor chambers 53 and 54.

For example, the control valve spool 41 of EVA and SO is
If it is slid to the right in Figure 1, the supply port 3
2 is connected to the power cylinder port 36 via the spool groove 47 of its control valve spool 41, and pressure oil is sent to the cylinder chamber 59 of the /('war cylinder 140, and the nokwar piston 61 is 1 to the left, in other words, the 9-war 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 curvature chamber 54 via the communication hole 52 and the bore 50.

The reaction force due to such steering is given by the pressure inside the rear control chamber 54, but as mentioned above, when driving at low speed, the reaction force adjustment valve 16 has a pair of communication ports 1.
-19 and 20 are extremely narrowed and communicated with each other with a wide passage cross-sectional area, so the pressure oil in the reactor chamber 54 is sent to the other reactor chamber 53.

Of course, the control valve spool 41 of 'C is
-i71, the discharge port 33 is connected to the stool groove 46, so that the pressure oil in the rear chamber 53 is returned to the suction side of the oil bomb 7'll.

Therefore, the pressure oil in the reactor chamber 54,
There is no large resistance to the sliding of the sonocontrol valve spool 41, and steering at low speeds can be performed with a small operating force.

If the control valve valve 41 is slid to the left in FIG. Pressure oil is sent to the cylinder chamber 60 of the power cylinder 14 and the reactor/con chamber 53 through passages 55 and 56, respectively, and
The piston 61 is moved to the right in FIG. 1, ie the mower 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, is extremely throttled by the reaction force adjustment valve 16, and is immediately sent to the reactor chamber 54, where it is Oil tank in rear chamber 54, via 50. It passes through the communication hole 52 and is returned to the suction side of the oil pump 11 from the discharge port 33.

Therefore, as in the case of ζ mentioned above, the reactor
The pressure oil in the chamber 53 is controlled by its control valve.
There is no large resistance to the sliding of the spool 41, and steering at low speeds can be performed with a small operating force.

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 communication ports 19 and 20 in the reaction force adjustment valve 16 is widened to the maximum. The pressure difference between the chambers 53 and 54 is extremely large.
Turning is possible with 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 throttled by its valve rotor 21, and the passage cross-sectional area is narrowed.

As before, if the control valve spool 41 is slid to either side, the cylinder chamber 59.6
Pressure oil is sent to one side of the power piston 61.
slides, and a part of the pressure oil is sent to either the reactor chamber 53 or '54 (7) (i'), but the connection port of the reaction force adjustment valve 16) is Since the cross-sectional area of the passage is narrowed, the reaction force adjustment valve 1
The pressure drop due to
The pressure difference in the chambers 53 and 54 increases, creating a large resistance to the sliding movement of the control valve valve 41, requiring a relatively large operating force to steer the vehicle at high speeds, which makes it difficult to drive. Improved 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 chamber 25 By .26, the valve rotor 21
The pressure is balanced in the axial direction within the valve bore 18, and the contact area on the upper and lower end surfaces of the valve rotor 21 is extremely small, so the frictional resistance of the valve rotor 21 is low and rotational speed is reduced. is performed smoothly, and as a result, the valve rotor 21 can be rotated with extremely small power. In other words, the valve rotor 21
It becomes possible to downsize the actuator 72 that rotates the .

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 valve rotor 21 is rotated slightly, the throttle groove 27 is connected to the communication port 19.
, substantially the same pressure is applied to each of its radial pressure chambers 29, 30, in other words, the valve rotor 21 is radially pressure balanced within its valve bore 18. This prevents the valve rotor 21 from shifting to one side, and allows the valve rotor 21 to rotate extremely smoothly.

Still, the valve shaft 22 of the valve rotor 21
is connected to the drive shaft 73 of the actuator 72 by a clearance fit joint 76 that allows eccentricity between the shafts, so that the power of the actuator 72 is reliably transmitted to the valve rotor 21. Of course, if there is a relative misalignment between the valve rotor 21 and the actuator 72 due to some variations in the actuator 72, such misalignment can be absorbed by the loose fit joint 76. Ru.

Therefore, the actuator 72 can be easily installed without requiring high precision when installing the actuator 72.
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 bore and a pair of communication ports opened to the valve via, and a valve casing configured to adjust the flow rate of pressure oil flowing between the communication ports. A valve rotor rotatably disposed in a bore, an actuator that drives the valve rotor, and within the valve bore,
A pair of radial pressure chambers communicated with each other so as to radially pressure balance the sonovalve rotor, and their communication in response to rotational movement of the valve rotor, j? - a throttle groove formed in the valve rotor, connecting the valve shaft of the valve rotor and the drive shaft of the actuator to each other so as to allow communication of one of the radial pressure chambers with one of the radial pressure chambers; And,
The valve has a radial pressure chamber that allows for eccentricity between the shafts.
The rotor is radially pressure balanced within its valve bore, which avoids offsetting of the valve rotor, makes rotation extremely smooth, and allows the valve rotor to be rotated with less power. In addition, the sensitivity is increased and the dynamic and static characteristics of the valve are improved.
The accuracy of flow regulation is improved, and the valve shaft of the valve rotor and the drive shaft of the actuator are connected to each other by the loose fit joint, and eccentricity between the shafts is tolerated. This makes it easier to connect the valve rotor and its actuator, and even if the valve shaft and drive shaft are not coaxially aligned and are misaligned, the gap can be reduced. The joint allows the power of the actuator to be properly transmitted to the valve rotor, making it most suitable as a reaction force regulating valve for use in power steering, making it extremely practical.

Further, the nozzle steering of the present invention, which includes a reaction force adjustment valve, is equipped with a pair of rear auxiliary chamber chambers on both sides of the oil pump, flow control valve, and control valve. A valve and a power cylinder are basically configured, a reactor communication passage communicates the pair of reactor chambers with each other, and the above-mentioned reaction force adjustment valve is provided in the reactor communication passage, and an actuator is provided. Since the pulp rotor of the reaction force adjustment valve is rotated according to the driving conditions of the vehicle, the reaction force when steering changes according to the driving conditions of the vehicle, and moreover, it is possible to change the reaction force from a stop to high speed driving. The most suitable reaction force for steering is obtained, enabling safe and reliable steering, and in addition, fatigue caused by steering is reduced, making it extremely practical.

As mentioned above, from the specific examples of the present invention explained with reference to the drawings, various design modifications and changes will be easily made by those having ordinary knowledge in the technical field to which this invention pertains. Furthermore, the structure of this invention can be easily converted into an embodiment essentially the same as this invention, which satisfies essentially the same problem as that invention and achieves the same effect as this invention. It would be possible to change tσ.

[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 sectional view showing a specific example of the reaction force adjustment valve of the present invention used in the 6-power steering shown in FIG. 1, and FIG. 4 is a cross-sectional view taken along a line, and FIG. 4 is a perspective view showing a clearance fit joint that allows eccentricity between shafts of the reaction force regulating valve in FIG. 2. 10. Power steering, Etooil Pon 7',
12. Flow control valve, 13. Control valve, 14. Power e7 cylinder, 15. Reaction control passage, 16. Reaction force adjustment valve, 17. Pulp casing, 18. Rotor bore, 19.20. Communication port, 21...Valve rotor, 22...Pulp...
Shaft, 23, 24...notch, 27...diaphragm groove,
28 ・Communication path, 29°30 ・Radial pressure chamber, 72
...Actuator, 73...Drive shaft, 7
6... Loose fit joint. Skin / figure tail 2I27 color tail i figure 2L, 3 2 Koma

Claims (2)

[Claims] (1) O'fol Pontft, Flow 9 Control
In a control valve equipped with a pair of rear auxiliary chambers on both sides of the palft, control valve, and spool, and a power cylinder, a rear auxiliary communication passage communicates the pair of rear auxiliary chambers with each other, A reaction force adjustment valve is disposed in the communication passage, and is connected to a valve casing having a pair of communication ports opened to the no cylinder bore and its/<//res bore, and between the communication ports. A pulp rotor rotatably disposed in the pulp bore so as to adjust the flow rate of the flowing pressure oil, an actuator for driving the pulp rotor, and a pulp rotor for driving the pulp rotor.
Within the pulp rotor, a pair of radial pressure chambers are connected to each other so as to radially pressure balance the pulp rotor, and one of the communication ports is connected in response to rotational movement of the pulp rotor. a throttle groove formed in the pulp rotor so as to allow one of the radial pressure chambers to communicate with each other, and connecting the valve shaft of the pulp rotor and the drive shaft of the actuator to each other; The steering wheel is characterized in that it includes a gap fit joint that allows eccentricity between the shafts of the earfts. (2) a pulp bore and a valve casing having a pair of communication ports opened in the valve bore, and a rotatable valve in the valve bore to adjust the flow rate of pressurized oil flowing between the communication boats; The valves located
a rotor; an actuator for driving the valve rotor; a pair of radial pressure chambers in communication with each other to radially pressure balance the valve rotor within the pulp bore; According to the rotational movement of the
1? a throttle groove formed in the valve rotor so as to enable communication of one of the radial pressure chambers with the valve rotor of the sonovalve rotor and the drive shaft of the actuator of the sonovalve rotor; A reaction force regulating valve used in power steering including a clearance fit joint that communicates the shafts with each other and allows eccentricity between the shafts.