JPH1191602A - Rotary valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of throttling noises due to cavitation by making the pressure in each exhaust chamber uniform even if the opening of reducing parts varies. SOLUTION: This rotary valve comprises between a sleeve valve member 20 and a rotor valve member 25 plural supply chambers R1a and R1b and exhaust chambers R3a and R3b arranged alternatingly, and control chambers intercommunicating with the supply chambers R1a and R1b and exhaust chambers R3a and R3b via reducing parts T1, T2, N1 through N6 that change openings according to the relative pivot movement of the valve members, with only the reducing parts T1 and T2 located between the plural first supply chambers R1a of a plurality of supply chambers and a pair of first control chambers R2a and R2b adjacent to both sides of the first supply chambers R1a in the rotating direction respectively configured to close at the neutral position of the relative pivot movement. All exhaust chambers are intercommunicated by an intercommunicating means. The plurality of exhaust chambers R3a and R3b may be intercommunicated in pair facing in the diametral direction by the 1st and 2nd intercommunicating means with an exhaust hole 28 provided with reducing action.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotary valve used for a power steering device and the like.

[0002]

2. Description of the Related Art FIG. 7 shows a rotary valve used in a power steering device of an automobile. This is provided with a sleeve valve member 1 and a rotor valve member 2 fitted to each other so as to rotate relative to each other according to a manual torque given from a steering handle. A plurality (eight in the illustrated example) of grooves 1a and 2a are provided at intervals in the circumferential direction, and are alternately arranged between both valve members 1 and 2 at intervals in the circumferential direction. The supply chambers 3 and the discharge chambers 5 (all four in the illustrated example) are provided between the supply chambers 3 and the discharge chambers 5 according to the relative rotation of the valve members 1 and 2. (8 in the illustrated example) communicated with the supply chamber 3 and the discharge chamber 5 through a plurality of (16 in the illustrated example) throttle portions 6a and 6b whose opening degrees change.
Of the control chambers 4a and 4b. This rotary valve supplies a working fluid from a positive displacement pump 7 to each supply chamber 3, discharges a working fluid from each discharge chamber 5 to a reservoir through a discharge hole 5 a, and controls each control chamber on both sides of each supply chamber 3. Reference numerals 4a and 4b are used so as to communicate with a power cylinder 8 that generates a steering assist force.

The working fluid having a predetermined flow rate flowing into each supply chamber 3 from the pump 7 is divided into two, and one of them is discharged from the discharge chamber 5 from the restrictor 6a through the control chamber 4a and the restrictor 6b to the reservoir. The other is discharged from the discharge chamber 5 to the reservoir through the control section 4b and the restriction section 6a from the throttle section 6b. In a state where steering is not performed, the two valve members 1 and 2 are in the neutral position of relative rotation, and the opening degrees of the throttle portions 6a and 6b are the same, so that the pressures in the control chambers 4a and 4b are the same and low. As a result, the power cylinder 8 does not generate any assisting force, and the pressure in each supply chamber 3 is also low. When the steering operation is performed and manual torque is applied, the two valve members 1 and 2 rotate relatively, and each of the eight throttle portions 6
The opening degree of one of a and 6b increases and the other opening degree decreases. For example, when the opening degree of the throttle section 6a increases and the opening degree of the throttle section 6b decreases, the pressure in the control chamber 4a increases, so that the power cylinder 8 generates a corresponding assist force. As the steering angle increases, the relative rotation angle of the two valve members 1 and 2 increases, and as the opening of the throttle portion 6b decreases, the pressure in the supply chamber 3 and the control chamber 4a increases, and the assist force increases. However, the flow velocity of the working fluid passing through the throttle portion 6b increases.

In a power steering apparatus using a rotary valve having a structure as shown in FIG. 7, an assist force is immediately generated when the steering wheel is rotated even slightly from the neutral steering position, so that a sense of response near the neutral steering position can be obtained. There is a problem that it is poor and the handle fluctuates. To solve this problem, for example, there is a technique disclosed in Japanese Patent Laid-Open No. 6-127401. In the structure shown in FIG. 7, this is located between two of the four supply chambers 3 facing left and right and four control chambers 4a and 4b adjacent on both sides in the circumferential direction. The four throttle portions 6a and 6b are configured to close at a neutral position of relative rotation, and the four control chambers 4a and 6b are closed.
Only a and b are connected to the power cylinder 8. With this configuration, no assist force is generated even when the steering wheel is slightly operated in the vicinity of the neutral steering position, so that the resistance when the steering wheel is rotated is increased.In other words, the rigidity of the steering is increased. A good steering feeling with a good response is obtained.

[0005]

Problems to be Solved by the Invention
According to the technique disclosed in Japanese Patent Application Publication No. 1-2006, for example, when steering is largely performed in a direction in which the opening degree of the throttle section 6b decreases, the control chamber 4b communicated with the power cylinder 8 among the eight throttle sections 6b.
Are closed, so that all the working fluid supplied from the positive displacement pump 7 is supplied to the remaining six throttle portions 6.
b to the reservoir through the discharge chamber 5. For this reason, the flow rate through one throttle portion 6b increases, and the flow velocity increases, so that cavitation is easily generated in the discharge chamber 5, but the cavitation is caused by the pressure in the discharge chamber 5 caused by the resistance of the discharge hole 5a. The lower the value, the more likely it is. Even if cavitation does not occur if the working fluid is evenly distributed to the six throttle portions 6b, if there is a difference in the opening degree of each of the throttle portions 6b due to a variation in processing of the valve members 1 and 2, the opening degree is reduced. The flow rate decreases in the small throttle portion 6b, but the flow velocity increases. In addition, the pressure generated by the resistance of the discharge hole 5a provided in the discharge chamber 5 corresponding to such a small throttle portion 6b decreases, so that the discharge is reduced. In some cases, cavitation occurs in the chamber 5 and a noise called a shoe (hereinafter referred to as a diaphragm sound) is generated. An object of the present invention is to prevent the generation of a diaphragm sound due to such a cause.

[0006]

SUMMARY OF THE INVENTION A rotary valve according to the present invention comprises a sleeve valve member and a rotor valve member which are relatively rotatably fitted to each other, and a fitting surface between an inner periphery of the sleeve valve member and an outer periphery of the rotor valve member. A plurality of grooves are provided at intervals in the circumferential direction, and a plurality of supply chambers and a plurality of discharge chambers are alternately arranged at intervals in the circumferential direction between the two valve members. A control chamber is provided between the supply chamber and the discharge chamber and communicates with the supply chamber and the discharge chamber through a throttle portion whose opening changes according to the relative rotation of the two valve members. A supply hole for supplying the working fluid is opened in the chamber, and a discharge hole for discharging the working fluid is opened in each of the discharge chambers. Each one adjacent
Only the throttle portion located between the pair of first control chambers and one of the first supply chamber and the discharge chamber on both sides thereof is configured to be substantially closed at the neutral position of relative rotation, and is operated by the operating device. The present invention relates to a rotary valve having a distribution hole for distributing and supplying fluid to each pair of first control chambers, wherein each discharge chamber is communicated by communication means. According to the present invention as described above, since each discharge chamber is communicated by the communication means, even if there is a difference in the opening degree of each throttle portion due to a variation in processing or the like, a pressure difference does not occur in each discharge chamber, There is no difference in the flow velocity of the working fluid passing through the throttle.

In the rotary valve according to the present invention, the discharge chambers located on the same side in the rotational direction with respect to the first supply chamber are respectively connected to the first supply chamber by the first and second communication means instead of connecting the discharge chambers by the communication means. The respective discharge holes communicate with each other to provide the same degree of restricting effect as the restricting portion between the plurality of second control chambers, which are the rest of the plurality of supply chambers, and each pair of second control chambers adjacent on both sides in the rotation direction. It may be provided. In this way, if there is a difference between the opening degrees of the respective throttle portions, the first and the second
A pressure difference occurs between the discharge chambers that are not communicated by the communication means, but the pressure in the discharge chamber as a whole increases due to the resistance of the discharge hole having the throttle effect as described above.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a power steering apparatus to which a rotary valve according to the present invention is applied will be described. As shown in FIG. 1, a pinion 12a of an output shaft 12 rotatably supported in gear housing 10 via bearings 17a and 17b.
Engages with rack teeth 15a of a rack shaft 15 slidably supported in a direction intersecting with the rack teeth. A piston 16a (see FIG. 2) of a power cylinder 16 is fixed to the rack shaft 15 and is not shown. It is connected to the steered wheels via a link mechanism. In a valve housing 11 fixed to the gear housing 10, an input shaft 13 connected to a steering handle via a handle shaft is provided coaxially with an output shaft 12 with bearings 18a and 18a.
18b so as to be rotatable via the two shafts 12, 1
Numeral 3 is connected via a torsion bar 14 so as to be relatively rotatable elastically. A rotary valve V according to the present invention is provided between the shafts 12 and 13. The rotary valve V includes a rotor valve member 25 formed integrally with the input shaft 13, an outer peripheral surface thereof and a valve hole 1 of the valve housing 11.
1a comprises a sleeve valve member 20 rotatably fitted to the output shaft 12 by a connecting pin 29 and comprising a supply port 31, a discharge port 35, and a pair of distribution ports 32.
a, 32b are connected to form a rotary type 4-port throttle switching valve.

Next, a first embodiment of the rotary valve V will be described with reference to FIGS. As shown in each figure, eight concave grooves 21 extending in the axial direction are formed on the inner peripheral surface of the sleeve valve member 20 at intervals in the circumferential direction, and a sleeve valve is formed on the outer peripheral surface of the rotor valve member 25. Eight land portions 27 substantially corresponding to the concave grooves 21 of the member 20 are formed, and between each of the land portions 27, a concave groove 26 is formed. Between the two valve members 20 and 25, four supply chambers R1a and R1b and four discharge chambers R3 are formed by the concave groove 26 of the rotor valve member 25.
a, R3b are formed alternately at intervals in the circumferential direction,
The supply chamber R1 is formed by the concave groove 21 of the sleeve valve member 20.
a, R1b and eight control chambers R2a to R2d located between the discharge chambers R3a, R3b. Each supply room R1
a, R1b, discharge chambers R3a, R3b and each control chamber R2a
To R2d are communicated via throttle portions T1, T2, N1 to N6 whose opening degree changes according to the relative rotation of the two valve members 20, 25.

[0010] The four supply chambers are composed of a pair of first supply chambers R1a and a pair of second supply chambers R that are diametrically opposed to each other and that are orthogonal to each other.
1b. The four closed throttle portions T1 and T2, which communicate each first supply chamber R1a and the first control chambers R2a and R2b adjacent to both sides thereof, are substantially at the neutral position of the relative rotation of the two valve members 20 and 25. When closed and rotated from the neutral position, one of the throttle portion T1 and the throttle portion T2 starts to open according to the direction of rotation. 1 remaining
The two open throttle portions N1 to N6 are open at the neutral position, and when rotated from the neutral position, one of the narrow portions N1, N4, N5 and one of the narrow portions N2, N3, N6 is opened according to the direction of rotation. The degree is increased and the other degree is decreased.

A supply port 31 provided in the valve housing 11 and a sleeve valve member 20 are provided in each of the supply chambers R1a and R1b.
The working fluid is supplied from the positive displacement pump 30 through the supply holes 22a and 22b formed in the discharge chambers R3a and R3.
3b is a discharge hole 28 formed in the rotor valve member 25, and a passage 3 formed between the input shaft 13 and the torsion bar 14.
3. It communicates with a reservoir 36 through a through hole 34 formed in the input shaft 13 and a discharge port 35 provided in the valve housing 11. The first control chambers R2a and R2b adjacent to the first supply chambers R1a are connected to the pistons of the power cylinder 16 through distribution holes 23a and 23b formed in the sleeve valve member 20 and distribution ports 32a and 32b provided in the valve housing 11. 16a communicates with the working chambers on both sides. The second control rooms R2c and R2d are not communicated with the outside.

As shown in FIGS. 1 and 3, an annular groove 24a is formed on the outer peripheral surface of the rotor valve member 25 at a position slightly away from one end of the concave groove 26, and the discharge chambers R3a, R3b are formed.
4 that connects the four concave grooves 26 forming the
The notch grooves 24b are formed. Sleeve valve member 2
0 has an inner peripheral surface slidably fitted to the outer peripheral surface of the rotor valve member 25 at both end portions thereof to close both ends of the groove 21.
The pair of press-fit sleeves 24 are fixed in a liquid-tight manner, and one press-fit sleeve 24 covers the annular groove 24a. In the first embodiment, the annular groove 24a and the four notched grooves 24b are
A communication means P for connecting the four discharge chambers R3a and R3b to each other is formed.

The fluid circuit of the power steering apparatus described above is schematically shown in FIG. However, in the rotary valve V of FIGS. 1 to 3, only two throttle portions T1, T2, N1 to N6 are provided in parallel, and FIG. 6 shows only one throttle portion.

Next, the operation of the above embodiment will be described.
In a state where steering is not performed, the rotary valve V is in the neutral position where the two valve members 20 and 25 are not relatively rotated, as shown in FIG. 2, and the closed throttle portions T1 and T2 are substantially closed. I have. Accordingly, a predetermined amount of the working fluid from the positive displacement pump 30 all flows into the two second supply holes 22b, and is divided into two in the second supply chamber R1b. One of the two is supplied from the open throttle portion N3 to the second control chamber R2c. , Open aperture section N5,
The other passes through the discharge chamber R3b and the discharge hole 28, and the other from the open throttle portion N4 to the second control chamber R2d, the open throttle portion N6,
After passing through the discharge chamber R3a and the discharge hole 28 and merging in the passage 33, it is discharged from the through hole 34 to the reservoir 36 through the discharge port 35. In this state, each first control room R2a,
Since the pressure in R2b is the same and very low, the power cylinder 16 does not generate an assist force,
a, The pressure in R1b is also low.

When a manual torque is applied by steering, the two valve members 20 and 25 rotate relatively, and the open throttle portion N1 and N2 are rotated.
Although the opening of one of N4, N5 and the open throttles N2, N3, N6 increases and the other decreases, each of the first throttles T1, T2 is substantially open until one of the closed throttles T1, T2 is substantially opened.
Since the pressures in the control chambers R2a and R2b remain the same and extremely low, no assist force is generated, and the neutral rigidity is increased. However, for example, the open throttle portions N2 and N
3, N6 opening increases, the open throttle parts N1, N4,
If the steering is performed in the direction in which the opening degree of N5 decreases and the closed throttle portion T1 substantially starts to open, the first control chamber R2
The pressure in the first control chamber R2b is increased by the working fluid flowing from the first supply chamber R1a through the closed throttle portion T1, while the pressure in the first control chamber R2b is increased while the closed throttle portion T2 is closed. , The power cylinder 16 generates an assist force due to the pressure difference. As the steering angle in this direction increases and the relative rotation angle between the two valve members 20 and 25 increases,
Since the degree of opening of the open throttle portions N1, N4, N5 decreases, the pressure in the supply chambers R1a, R1b, the first control chamber R2a, and the second control chamber R2c increases, and the assisting force by the power cylinder 16 increases. It should be noted that the closed throttle portion T1 in series with the open throttle portion N1 is an open throttle portion N4.
Since the opening degree is smaller than the open throttle portions N3 and N6 in series with N5, the flow rate of the working fluid passing through the open throttle portion N1 is smaller than the flow speed passing through the open throttle portions N4 and N5.

In this case, the pressure in the discharge chamber R3b is lower than the pressure in the second control chamber R2d. Therefore, when the vehicle is steered to near the maximum steering angle, it passes through the open throttle portion N5 and enters the discharge chamber R3b. The inflowing working fluid approaches the limit at which cavitation occurs before the working fluid flows into the second control chamber R2d through the open throttle portion N4.
If the opening degrees of the left and right open throttles N5 vary due to processing errors of the respective valve members 20, 25, the pressure in the left and right discharge chambers R3b and the flow rate of the working fluid passing through the open throttles N5 vary. There is a possibility that cavitation may be generated first in one of the open aperture portions N5 to generate an aperture sound. However, in the above-described embodiment, variations in pressure and flow velocity due to such causes are averaged by the communicating means P as described below, and cavitation and thus no throttle noise are generated.

For example, in FIG. 2, consider a case where the opening degree of the left open throttle portion N5 is smaller than a normal value. In this case, since the flow resistance of each discharge hole 28 is small but not zero, the flow velocity passing through the left and right open throttle portions N5 becomes faster on the left side than on the right side without the communication means P. The flow rate passing through N5 is smaller on the left side than on the right side, and the pressure in the left discharge chamber R3b is lower than the pressure in the other discharge chambers R3a and R3b, thereby causing cavitation in the left discharge chamber R3b. This may cause a diaphragm sound. However, in the above embodiment, since the discharge chambers R3a and R3b are communicated by the communication means P, the pressure inside the discharge chambers R3a and R3b is the same, and the flow velocity through the left and right open throttle portions N5 is also the same. As a result, cavitation does not occur in the left discharge chamber R3b, and no throttle noise is generated. At this time, a flow of the working fluid from the discharge chamber R3b on the right side to the other discharge chambers R3a and R3b occurs in the communication means P.

Even when the opening degree of the right open aperture portion N5 becomes smaller than a normal value, no aperture sound is generated similarly. When both the left and right open throttles N5 become smaller than the normal values, the flow rates through the left and right open throttles N5 become faster and the flow through the respective open throttles N5 without the communication means P. Are both decreasing,
Although the pressure in each discharge chamber R3b becomes lower than the pressure in the other discharge chamber R3a, in the above-described embodiment, the pressure in each of the discharge chambers R3a and R3b becomes the same by the communication means P, and therefore, The cavitation does not occur and the diaphragm sound does not occur. In this case, a flow of the working fluid from the discharge chamber R3b to the other discharge chamber R3a occurs in the communication means P.

The above is the case where the opening degrees of the open throttle portions N1, N4, N5 are reduced.
Similarly, even when the opening degree of N6 is reduced, the pressure in one or both of the left and right discharge chambers R3a does not decrease. Therefore, it is possible that cavitation in the discharge chamber R3a causes a throttling sound. Disappears.

FIG. 4 shows a second embodiment of the rotary valve according to the present invention.
An embodiment will be described. In the first embodiment, the communication means P for communicating the discharge chambers R3a and R3b is provided with the rotor valve member 2.
Although provided on the side of the sleeve valve member 20 in this second embodiment. Other configurations are the same as those of the first embodiment, and only the structure of the communication means P will be described.

In the second embodiment, there is no structure corresponding to the annular groove 24a and the notch groove 24b of the first embodiment, and instead, a press-fit sleeve fixed to both inner circumferential ends of the sleeve valve member 20. An annular groove 24d is formed in the inner peripheral surface of one of the 24. The discharge chamber R3 of the eight concave grooves 26 formed on the outer peripheral surface of the rotor valve member 25 is formed.
The four concave grooves 26a forming a and R3b extend at one end on the press-fit sleeve 24c side and are configured to communicate with the annular groove 24d. Thus, in the second embodiment, the annular groove 24d forms a communication unit P that connects the four discharge chambers R3a and R3b to each other.

The second embodiment operates in the same manner as the first embodiment. Even when the opening degrees of the left and right open throttle portions N4 and N5 vary, any one of the discharge chambers R3a and R3b can be used. The internal pressure does not decrease, so that no squeezing noise is generated in the discharge chambers R3a and R3b due to cavitation.

FIG. 5 shows a third embodiment of the rotary valve according to the present invention.
An embodiment will be described. In the third embodiment, the communication means for communicating the discharge chambers R3a and R3b is provided in the discharge chamber R3 located on the same side in the rotational direction with respect to the first supply chamber R1a.
a, R3b, that is, a pair of discharge chambers R3a diametrically opposed to each other in the specific shape shown in FIG.
And discharge chambers R3b are separated into first and second communication means P1 and P2 for communicating with each other. Since other configurations are the same as those of the first embodiment, only the structure of the first and second communication means P1 and P2 will be described.

In the third embodiment, a pair of annular grooves 40a and 40b are formed on the outer peripheral surface of the rotor valve member 25 at positions slightly away from both ends of the concave groove 26, and the discharge chamber R3a is formed. Two notches 40c are formed to communicate the two grooves 26 to be formed and the annular groove 40a, and two notches 40d are formed to communicate the two grooves 26 and the annular groove 40b forming the discharge chamber R3b. Have been. Each press fitting sleeve 24 of the sleeve valve member 20 covers each annular groove 40a, 40b.
The annular groove 40a and the notch groove 40c form a first communicating means P1 for communicating a pair of diametrically opposed discharge chambers R3a with each other, and the annular groove 40b and the notch groove 40d diametrically oppose a pair of discharges. A second communication means P2 for communicating the chambers R3b with each other is formed.

In the third embodiment, each discharge chamber R3
The diameter of the discharge hole 28 opened to a and R3b is reduced as shown by a two-dot chain line in FIG. 2 to give a throttle effect, and a two-stage throttle is constituted by the open throttle portions N1 to N6. This is to provide an appropriate resistance when the working fluid passes through the discharge hole 28, and to increase the pressure in the discharge chambers R3a and R3b somewhat to prevent cavitation. For example, the same as the open throttle portions N1 to N6. What is necessary is just to have a degree of aperture effect.

For example, when the opening of the open throttle portions N1, N4 and N5 is operated in a direction in which the opening degree decreases, if the opening of the left open throttle portion N5 becomes smaller than a normal value, the second Without the communication means P2, the pressure in the left discharge chamber R3b is lower than that in the right discharge chamber R3b. However, in the third embodiment, the left and right discharge chambers R3b are connected by the second communication means P2. Therefore, each discharge hole 28 has the above-described throttling effect, and as a result, the pressure in each of the discharge chambers R3a and R3b increases as a whole, so that cavitation occurs in the discharge chamber R3b. It does not occur and does not produce an aperture sound. Similarly, when the opening degree of the right open aperture portion N5 becomes smaller than a normal value, no aperture sound is generated.

If both the left and right open diaphragms N5 become smaller than the normal values, the left and right open diaphragms N5
5, each flow speed becomes faster, and each open throttle portion N
5, the pressure in each discharge chamber R3b becomes equal to each other, but lower than the pressure in the other discharge chamber R3a. However, each of the discharge holes 28 has the above-described throttling effect, and the pressure in each of the discharge chambers R3a and R3b increases as a whole, so that cavitation does not occur in the discharge chamber R3b and no throttling noise is generated. .

The above is the case where the opening of the open throttle portions N1, N4, N5 is operated in a direction in which the opening degree is decreased. Similarly, no squeezing noise is generated by cavitation in the discharge chamber R3a.

In each of the above embodiments, the first control room R2
a, R2b and the first supply chamber R1a are provided with closed throttles T1 and T2, and the first control chambers R2a and R2b are provided with open throttles N1 and N2 between the discharge chambers R3a and R3b. In the present invention, the closed throttle portions T1 and T2 and the open throttle portions N1 and N2 are interchanged, that is, open throttle portions N1 and N2 are provided between the first control chambers R2a and R2b and the first supply chamber R1a. Closed throttle portions T1 and T2 may be provided between R2b and the discharge chambers R3a and R3b.

[0030]

As described above, according to the present invention, since each discharge chamber is communicated by the communication means, even if there is a difference in the opening degree of each throttle due to a variation in processing, the pressure in each discharge chamber is increased. There is no difference, and there is no difference in the flow rate of the working fluid through each throttle. Therefore, even if there is a difference in the opening degree of the throttle section, the pressure in some of the discharge chambers is reduced, and cavitation does not occur inside the chamber, thereby preventing the generation of a throttle sound.

According to the first supply chamber, the discharge chambers located on the same side in the rotation direction communicate with each other, and each discharge hole is provided with a throttle effect, and is formed on the same side of each discharge chamber. If there is a variation in the degree of opening of each throttle, a pressure difference occurs between the discharge chambers that are not communicated by the first and second communication means. However, even in the discharge chamber having a lower pressure, the pressure inside the discharge hole having the above-described throttling effect increases due to the resistance of the discharge hole having the above-described throttling effect.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a power steering device to which a first embodiment of a rotary valve according to the present invention is applied.

FIG. 2 is a cross-sectional view of the first embodiment applied to FIG.

FIG. 3 is a longitudinal sectional view of the sleeve valve member of the first embodiment applied to FIG.

FIG. 4 is a longitudinal sectional view of a second embodiment of the rotary valve according to the present invention.

FIG. 5 is a side view of a rotor valve member of a rotary valve according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a fluid circuit of the power steering device shown in FIG. 1;

FIG. 7 is a cross-sectional view corresponding to FIG. 2, illustrating an example of a rotary valve according to the related art.

[Explanation of symbols]

20: sleeve valve member, 21: concave groove, 22a, 22b ...
Supply holes, 23a, 23b ... distribution holes, 25 ... rotor valve members, 26 ... concave grooves, 28 ... discharge holes, P ... communication means, P1 ...
First communication means, P2... Second communication means, R1a.
Supply chamber, R1b ... second supply chamber, R2a, R2b ... first control chamber, R2c, R2d ... second control chamber, R3a, R3b ...
Discharge chamber, N1 to N6 ... throttle part (open throttle part), T
1, T2: throttle section (closed throttle section).

Claims (2)

[Claims] 1. A sleeve valve member and a rotor valve member which are fitted to each other so as to be relatively rotatable, and a plurality of concave grooves are respectively formed on fitting surfaces of an inner periphery of the sleeve valve member and an outer periphery of the rotor valve member. A plurality of supply chambers and a plurality of discharge chambers are provided at intervals in the circumferential direction and are alternately arranged at intervals in the circumferential direction between the two valve members. A control chamber is provided between the supply chamber and the discharge chamber through a throttle portion that is located between the two and has a degree of opening that changes in accordance with the relative rotation of the two valve members. And a discharge hole for discharging a working fluid is opened in each of the discharge chambers, and a plurality of first supply chambers adjacent to both sides in the rotation direction of a plurality of first supply chambers which are a part of the plurality of supply chambers. Before being located between a pair of first control chambers and one of the first supply chamber and the discharge chamber on both sides thereof In the rotary valve, only the throttle portion is configured to be substantially closed at the neutral position of the relative rotation, and the distribution holes for distributing the working fluid to the operating device are opened to the pair of first control chambers. A rotary valve, wherein each of the discharge chambers is communicated by communication means. 2. A sleeve valve member and a rotor valve member which are fitted to each other so as to be relatively rotatable. A plurality of concave grooves are respectively formed on fitting surfaces of an inner periphery of the sleeve valve member and an outer periphery of the rotor valve member. A plurality of supply chambers and a plurality of discharge chambers are provided at intervals in the circumferential direction and are alternately arranged at intervals in the circumferential direction between the two valve members. A control chamber is provided between the supply chamber and the discharge chamber through a throttle portion that is located between the two and has a degree of opening that changes in accordance with the relative rotation of the two valve members. And a discharge hole for discharging the working fluid is opened in each of the discharge chambers, and is adjacent to both sides in the rotational direction of the plurality of first supply chambers that are a part of the plurality of supply chambers. A position is located between each pair of first control chambers and one of the first supply chamber and the discharge chamber on both sides thereof. The rotary section is configured such that only the throttle section to be disposed is substantially closed at the neutral position of the relative rotation, and a distribution hole for distributing the working fluid to the operating device is opened in each of the pair of first control chambers. In the valve, the discharge chambers located on the same side in the rotation direction with respect to the first supply chamber are communicated by first and second communication means, respectively.
Each of the discharge holes has the same degree of restricting effect as the restrictor between a plurality of second supply chambers, which are the rest of the plurality of supply chambers, and a pair of second control chambers adjacent to both sides in the rotation direction. A rotary valve, comprising: a rotary valve;