Rotary valve system

Abstract

This rotary valve system comprises: a body that has a body high-pressure port, a body low-pressure port, and a body output port; a stator that is disposed inside the body and has a stator output port connected to the body output port through an output flow path provided in the body; a rotating body that is disposed inside the stator and has a high-pressure port groove to which hydraulic oil from the body high-pressure port is supplied, and a low-pressure port groove that is provided at a position different from the high-pressure port groove in the circumferential direction and to which hydraulic oil from the body low-pressure port is supplied; and a controller that controls the rotation of the rotating body. The controller causes the rotating body to rotate so as to change each of a time in a high-pressure connection state in which the body high-pressure port and the body output port are connected through the high-pressure port groove and the stator output port, and a time in a low-pressure connection state in which the body low-pressure port and the body output port are connected through the low-pressure port groove and the stator output port.

Description

Rotary Valve System

[0001] The present disclosure relates to rotary valve systems.

[0002] In the technical field relating to rotary valves, a rotary valve such as that disclosed in Patent Document 1 is known.

[0003] U.S. Patent No. 7,322,375

[0004] Conventional rotary valves may be susceptible to distortion due to hydraulic oil pressure. Increasing the clearance between components of the rotary valve to prevent distortion may result in increased hydraulic oil leakage.

[0005] The present disclosure aims to improve the performance of rotary valves.

[0006] According to the present disclosure, there is provided a rotary valve system including: a body having a body high-pressure port, a body low-pressure port, and a body output port; a stator disposed inside the body and having a stator output port connected to the body output port via an output flow passage provided in the body; a rotor disposed inside the stator and having a high-pressure port groove to which hydraulic oil is supplied from the body high-pressure port and a low-pressure port groove located at a position different from the high-pressure port groove in the circumferential direction to which hydraulic oil is supplied from the body low-pressure port; and a controller that controls rotation of the rotor. The controller rotates the rotor to change the time of a high-pressure connected state in which the body high-pressure port and the body output port are connected via the high-pressure port groove and the stator output port, and the time of a low-pressure connected state in which the body low-pressure port and the body output port are connected via the low-pressure port groove and the stator output port.

[0007] The present disclosure improves the performance of rotary valves.

[0008] FIG. 1 is a perspective view showing a rotary valve according to a first embodiment. FIG. 2 is a cross-sectional view showing a rotary valve according to the first embodiment. FIG. 3 is a cross-sectional view showing a rotary valve according to the first embodiment. FIG. 4 is a cross-sectional view showing a rotary valve according to the first embodiment. FIG. 5 is a cross-sectional view showing a rotary valve according to the first embodiment. FIG. 6 is a perspective view showing a rotor according to the first embodiment. FIG. 7 is a perspective view showing a stator according to the first embodiment. FIG. 8 is a schematic view showing a rotary valve according to the first embodiment. FIG. 9 is a diagram showing the relationship between high-pressure connection state and low-pressure connection state and time according to the first embodiment. FIG. 10 is a diagram explaining the operation of the rotary valve according to the first embodiment. FIG. 11 is a diagram showing the relationship between the rotor angle, the area of ​​the flow path of hydraulic oil, and the target value of the rotation speed of the rotor according to the first embodiment. FIG. 12 is a diagram showing the relationship between the area of ​​the flow path of hydraulic oil and time according to the first embodiment. FIG. 13 is a diagram explaining a method for determining the rotation speed of the rotor according to the first embodiment. FIG. 14 is a cross-sectional view showing a rotary valve according to a second embodiment. FIG. 15 is a cross-sectional view showing a rotary valve according to the second embodiment. FIG. 16 is a cross-sectional view showing a rotary valve according to the second embodiment. FIG. 17 is a cross-sectional view showing a rotary valve according to a second embodiment. FIG. 18 is a perspective view showing a control shaft according to the second embodiment. FIG. 19 is a perspective view showing a rotor according to the second embodiment. FIG. 20 is a perspective view showing a stator according to the second embodiment. FIG. 21 is a schematic view of a rotary valve according to the second embodiment. FIG. 22 is a view explaining the operation of the rotary valve according to the second embodiment. FIG. 23 is a view showing the relationship between the rotor angle and the area of ​​the high-pressure side flow path of hydraulic oil according to the second embodiment. FIG. 24 is a view showing the relationship between the rotor angle and the area of ​​the high-pressure side flow path of hydraulic oil according to the second embodiment. FIG. 25 is a view showing the relationship between the rotor angle and the area of ​​the high-pressure side flow path of hydraulic oil according to the second embodiment. FIG. 26 is a view explaining an example of use of a rotary valve according to a third embodiment. FIG. 27 is a view explaining an example of use of a rotary valve according to the third embodiment.

[0009] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiments. In the embodiments, a three-dimensional Cartesian coordinate system is set for the rotary valve, and the positional relationship of each part will be described with reference to the three-dimensional Cartesian coordinate system. The direction parallel to the X axis within a predetermined plane is defined as the X-axis direction. The direction parallel to the Y axis orthogonal to the X axis within the predetermined plane is defined as the Y-axis direction. The direction parallel to the Z axis orthogonal to the predetermined plane is defined as the Z-axis direction. One side of the X-axis direction is defined as the +X side, and the other side is defined as the -X side. One side of the Y-axis direction is defined as the +Y side, and the other side is defined as the -Y side. One side of the Z-axis direction is defined as the +Z side, and the other side is defined as the -Z side.

[0010] First Embodiment A first embodiment will be described.

[0011] FIG. 1 is a perspective view showing a rotary valve 1A according to this embodiment. FIGS. 2, 3, 4, and 5 are cross-sectional views showing the rotary valve 1A according to this embodiment. FIG. 2 corresponds to a cross-sectional view taken along line A1-A1 in FIG. 1. FIG. 3 corresponds to a cross-sectional view taken along line B1-B1 in FIG. 2. FIG. 4 corresponds to a cross-sectional view taken along line C1-C1 in FIG. 2. FIG. 5 corresponds to an enlarged view of a portion of FIG. 4.

[0012] The rotary valve 1A includes a rotor 2A, a stator 4A, and a body 5. The body 5 has a body high-pressure port 51, a body low-pressure port 52, and a body output port 53. The stator 4A is disposed inside the body 5. An output flow path 54 is provided inside the body 5. The stator 4A has a stator output port 43 connected to the body output port 53 via the output flow path 54. The rotor 2A is disposed inside the stator 4A. The outer surface of the rotor 2A faces the inner surface of the stator 4A. The outer surface of the rotor 2A contacts the inner surface of the stator 4A. The rotor 2A rotates around a rotation axis AX inside the stator 4A. The rotation axis AX is parallel to the X-axis.

[0013] In the following description, the direction parallel to the rotation axis AX will be referred to as the axial direction, the direction circumferentially around the rotation axis AX will be referred to as the circumferential direction or rotational direction, and the radial direction of the rotation axis AX will be referred to as the radial direction.

[0014] 6 is a perspective view showing a rotating body 2A according to this embodiment. The rotating body 2A is a rod-shaped member that is long in the X-axis direction. The rotating body 2A has a central rod portion 20, end rod portions 21 and 22, a high-pressure recess 23, a low-pressure recess 24, a high-pressure port groove 25, a low-pressure port groove 26, and an operating rod portion 27.

[0015] The central rod portion 20 is long in the X-axis direction. The end rod portion 21 is disposed on the −X side of the central rod portion 20. The end rod portion 22 is disposed on the +X side of the central rod portion 20. Each of the central rod portion 20, the end rod portion 21, and the end rod portion 22 is substantially cylindrical. In the X-axis direction, the dimension of the central rod portion 20 is larger than the dimension of the end rod portion 21 and the dimension of the end rod portion 22.

[0016] The high-pressure recess 23 is provided between the central rod portion 20 and the end rod portion 21. The high-pressure recess 23 is annular. The low-pressure recess 24 is provided between the central rod portion 20 and the end rod portion 22. The low-pressure recess 24 is annular. The operating rod portion 27 protrudes toward the +X side from the +X side end of the end rod portion 22.

[0017] The high-pressure port groove 25 is a groove that is long in the X-axis direction and is formed on the outer surface of the central rod section 20. In the X-axis direction, at least a portion of the high-pressure port groove 25 is located on the −X side of the center of the central rod section 20. The −X-side end of the high-pressure port groove 25 is located at the −X-side end of the central rod section 20. The −X-side end of the high-pressure port groove 25 reaches the −X-side end of the central rod section 20. The −X-side end of the high-pressure port groove 25 is connected to the high-pressure recess 23. The hydraulic oil supplied to the high-pressure recess 23 flows into the high-pressure port groove 25. In the X-axis direction, the +X-side end of the high-pressure port groove 25 is located at the center of the central rod section 20.

[0018] A plurality of high-pressure port grooves 25 are provided at equal intervals in the circumferential direction. In this embodiment, six high-pressure port grooves 25 are provided in the circumferential direction.

[0019] The low-pressure port groove 26 is a groove that is long in the X-axis direction and is formed on the surface of the central rod section 20. In the X-axis direction, at least a portion of the low-pressure port groove 26 is provided on the +X side of the center of the central rod section 20. The +X-side end of the low-pressure port groove 26 is located at the +X-side end of the central rod section 20. The +X-side end of the low-pressure port groove 26 reaches the +X-side end of the central rod section 20. The +X-side end of the low-pressure port groove 26 is connected to the low-pressure recess 24. Hydraulic oil supplied to the low-pressure recess 24 flows into the low-pressure port groove 26. In the X-axis direction, the −X-side end of the low-pressure port groove 26 is located at the center of the central rod section 20.

[0020] A plurality of low-pressure port grooves 26 are provided at equal intervals in the circumferential direction. In this embodiment, six low-pressure port grooves 26 are provided in the circumferential direction.

[0021] The high-pressure port groove 25 and the low-pressure port groove 26 are provided at different positions in the axial direction. The +X side end of the high-pressure port groove 25 is positioned closer to the −X side than the −X side end of the low-pressure port groove 26. The high-pressure port groove 25 and the low-pressure port groove 26 do not overlap in the axial direction.

[0022] The high-pressure port groove 25 and the low-pressure port groove 26 are provided at different positions in the circumferential direction. The low-pressure port groove 26 is positioned in the center of the pair of high-pressure port grooves 25 in the circumferential direction. When the high-pressure port grooves 25 are provided at positions of 0°, 60°, 120°, 180°, 240°, and 300° in the circumferential direction, the low-pressure port grooves 26 are provided at positions of 30°, 90°, 150°, 210°, 270°, and 330°.

[0023] The high-pressure port groove 25 and the low-pressure port groove 26 have the same dimension in the circumferential direction. That is, the high-pressure port groove 25 and the low-pressure port groove 26 have the same groove width.

[0024] High-pressure hydraulic oil from the body high-pressure port 51 is supplied to the high-pressure port groove 25. Low-pressure hydraulic oil from the body low-pressure port 52 is supplied to the low-pressure port groove 26. Hydraulic oil from the body high-pressure port 51 is not supplied to the low-pressure port groove 26. Hydraulic oil from the body low-pressure port 52 is not supplied to the high-pressure port groove 25.

[0025] The rotating body 2A rotates so that the high-pressure port groove 25 and the stator output port 43 are switched between a connected state and a disconnected state. The rotating body 2A rotates so that the low-pressure port groove 26 and the stator output port 43 are switched between a connected state and a disconnected state. The rotating body 2A rotates so that the overlapping area between the high-pressure port groove 25 and the stator output port 43 changes. The rotating body 2A rotates so that the overlapping area between the low-pressure port groove 26 and the stator output port 43 changes.

[0026] 7 is a perspective view showing a stator 4A according to this embodiment. The stator 4A is a cylindrical member that is long in the X-axis direction. The stator 4A has a cylindrical portion 40, a stator high-pressure port 41, a stator low-pressure port 42, a stator output port 43, and a flange portion 44.

[0027] The cylindrical portion 40 is disposed around at least a portion of the rotating body 2A. The cylindrical portion 40 is disposed around the central rod portion 20. The outer surface of the central rod portion 20 faces the inner surface of the cylindrical portion 40. The outer surface of the central rod portion 20 contacts the inner surface of the cylindrical portion 40. An opening is provided at each of the +X side end and the -X side end of the cylindrical portion 40. The central rod portion 20 is inserted into the cylindrical portion 40 through the opening at the +X side end or the opening at the -X side of the cylindrical portion 40. The flange portion 44 is provided around the -X side end of the cylindrical portion 40.

[0028] The stator high-pressure port 41 is provided at the end of the cylindrical portion 40 on the -X side. The stator high-pressure port 41 is a hole that penetrates the outer surface and inner surface of the cylindrical portion 40. In this embodiment, the stator high-pressure port 41 is an elongated hole that is long in the circumferential direction. Six stator high-pressure ports 41 are provided at equal intervals in the circumferential direction. In the X-axis direction, the positions of the stator high-pressure ports 41 and the high-pressure recess 23 coincide. The hydraulic oil that passes through the stator high-pressure port 41 is supplied to the high-pressure recess 23.

[0029] The stator low-pressure port 42 is provided at the end of the cylindrical portion 40 on the +X side. The stator low-pressure port 42 is a hole that penetrates the outer surface and inner surface of the cylindrical portion 40. In this embodiment, the stator low-pressure port 42 has a rectangular shape that is long in the X-axis direction. Six stator low-pressure ports 42 are provided at equal intervals around the circumference. In the X-axis direction, the positions of the stator low-pressure ports 42 and the low-pressure recess 24 coincide with each other. The hydraulic oil that passes through the stator low-pressure port 42 is supplied to the low-pressure recess 24.

[0030] The stator output port 43 is provided between the stator high-pressure port 41 and the stator low-pressure port 42 in the X-axis direction. The stator output port 43 is a hole that penetrates the outer surface and the inner surface of the cylindrical portion 40. In the present embodiment, the stator output port 43 has an elliptical shape that is long in the X-axis direction. The size of the stator output port 43 is smaller than the size of the stator high-pressure port 41 and the size of the stator low-pressure port 42.

[0031] Four stator output ports 43 are provided in the X-axis direction. An even number of 10 or more stator output ports 43 are provided in the circumferential direction. In this embodiment, 12 stator output ports 43 are provided at equal intervals in the circumferential direction. The four stator output ports 43 arranged in the X-axis direction are arranged at equal positions in the circumferential direction. In other words, the four stator output ports 43 arranged in the X-axis direction are arranged in a straight line in the X-axis direction.

[0032] In the X-axis direction, the positions of the two stator output ports 43 on the −X side of the center of the cylindrical portion 40 coincide with the position of the high-pressure port groove 25. The two stator output ports 43 on the −X side overlap with the high-pressure port groove 25 in the X-axis direction.

[0033] In the X-axis direction, the positions of the two stator output ports 43 on the +X side of the center of the cylindrical portion 40 coincide with the positions of the low-pressure port grooves 26. The two stator output ports 43 on the +X side overlap with the low-pressure port grooves 26 in the X-axis direction.

[0034] The two stator output ports 43 on the −X side are an example of first stator output ports that can be connected to the high-pressure port groove 25. The two stator output ports 43 on the −X side are not connected to the low-pressure port groove 26. The two stator output ports 43 on the +X side are an example of second stator output ports that can be connected to the low-pressure port groove 26. The two stator output ports 43 on the +X side are not connected to the high-pressure port groove 25.

[0035] The body 5 has an accommodation space 50, a body high-pressure port 51, a body low-pressure port 52, a body output port 53, an output flow path 54, and a connecting flow path 55. The accommodation space 50 is formed inside the body 5. The accommodation space 50 is a cylindrical space that is long in the X-axis direction. The stator 4A is accommodated inside the accommodation space 50. The outer surface of the stator 4A faces the inner surface of the accommodation space 50. The outer surface of the stator 4A contacts the inner surface of the accommodation space 50. With the stator 4A disposed inside the accommodation space 50, the opening on the -X side of the accommodation space 50 is covered with a cover 6, and the opening on the +X side of the accommodation space 50 is covered with a cover 7. The operating rod portion 27 protrudes to the +X side from an opening provided in the center of the cover 7.

[0036] The body high-pressure port 51 is connected to the stator high-pressure port 41. High-pressure hydraulic oil is supplied from the body high-pressure port 51 to the stator high-pressure port 41. The high-pressure hydraulic oil supplied to the stator high-pressure port 41 is supplied to the high-pressure recess 23. The high-pressure hydraulic oil supplied to the high-pressure recess 23 flows through the high-pressure port groove 25, and then can flow into the two stator output ports 43 on the −X side of the cylindrical portion 40.

[0037] The body low-pressure port 52 is connected to the stator low-pressure port 42. Low-pressure hydraulic oil is supplied from the body low-pressure port 52 to the stator low-pressure port 42. The low-pressure hydraulic oil supplied to the stator low-pressure port 42 is supplied to the low-pressure recess 24. The hydraulic oil supplied to the low-pressure recess 24 flows through the low-pressure port groove 26, and then can flow into the two stator output ports 43 on the +X side of the cylindrical portion 40.

[0038] The output flow passages 54 are formed to penetrate the outer surface of the body 5 and the inner surface of the accommodation space 50. The output flow passages 54 communicate with the accommodation space 50. Six output flow passages 54 are provided in the circumferential direction. Four output flow passages 54 are provided in the axial direction. The multiple output flow passages 54 are interconnected by connecting flow passages 55. The openings of the connecting flow passages 55 formed in the outer surface of the body 5 are closed by plugs 8. The openings of the output flow passages 54 formed in the outer surface of the body 5 are closed by plugs 9.

[0039] The stator 4A is fixed to the body 5. The stator 4A does not rotate, and the relative position between the body 5 and the stator 4A does not change.

[0040] As shown in Fig. 5, twelve stator output ports 43 are provided in the circumferential direction. Six output flow paths 54 are provided in the circumferential direction. The radially inner openings of the output flow paths 54 are provided at equal intervals in the circumferential direction. The stator output ports 43 include a stator output port 43A connected to the output flow paths 54 and a stator output port 43B that is not connected to the output flow paths 54 and is closed by the inner surface of the accommodation space 50. The stator output ports 43A and the stator output ports 43B are provided alternately in the circumferential direction.

[0041] Of the four output flow paths 54 provided in the X-axis direction, the two output flow paths 54 on the −X side are connected to the two stator output ports 43A on the −X side. Of the four output flow paths 54 provided in the X-axis direction, the two output flow paths 54 on the +X side are connected to the two stator output ports 43A on the +X side.

[0042] Six high-pressure port grooves 25 are provided in the circumferential direction. Twelve stator output ports 43 are provided in the circumferential direction. The dimensions of the high-pressure port grooves 25 and the stator output port 43 are equal in the circumferential direction. When the high-pressure port grooves 25 and the stator output port 43B are connected, the high-pressure port grooves 25 and the stator output port 43A are not connected. When the high-pressure port grooves 25 and the stator output port 43A are connected, the high-pressure port grooves 25 and the stator output port 43B are not connected. As the rotating body 2A rotates, switching is performed between a state in which the high-pressure port grooves 25 and the stator output port 43A are not connected but the high-pressure port grooves 25 and the stator output port 43B are connected, and a state in which the high-pressure port grooves 25 and the stator output port 43B are not connected but the high-pressure port grooves 25 and the stator output port 43A are not connected.

[0043] Six low-pressure port grooves 26 are provided in the circumferential direction. Twelve stator output ports 43 are provided in the circumferential direction. The dimensions of the low-pressure port grooves 26 and the stator output port 43 are equal in the circumferential direction. When the low-pressure port grooves 26 and the stator output port 43A are connected, the low-pressure port grooves 26 and the stator output port 43B are not connected. When the low-pressure port grooves 26 and the stator output port 43B are connected, the low-pressure port grooves 26 and the stator output port 43A are not connected. As the rotating body 2A rotates, switching is performed between a state in which the low-pressure port grooves 26 and the stator output port 43B are not connected but the low-pressure port grooves 26 and the stator output port 43A are connected, and a state in which the low-pressure port grooves 26 and the stator output port 43A are not connected but the low-pressure port grooves 26 and the stator output port 43B are not connected.

[0044] Fig. 8 is a diagram schematically illustrating a rotary valve 1A according to this embodiment. As shown in Fig. 8, a motor 61 is connected to the operating rod portion 27 of a rotor 2A. The rotor 2A rotates around a rotation axis AX inside the stator 4A by the rotational force generated by the motor 61. The motor 61 is controlled by a controller 10. The rotary valve 1A and the controller 10 constitute a rotary valve system.

[0045] The controller 10 includes a computer. The controller 10 includes a processor 10A, a storage device 10B, and an input / output interface 10C. The processor 10A includes a CPU (Central Processing Unit). The storage device 10B includes a recording medium on which computer programs and data are recorded so as to be readable by the processor 10A. The storage device 10B includes a system memory such as a RAM (Random Access Memory) or a ROM (Read Only Memory), and an auxiliary storage device. Examples of the auxiliary storage device include a hard disk or a semiconductor memory. A control signal output from the processor 10A is transmitted to the motor 61 via the input / output interface 10C.

[0046] As described above, six high-pressure port grooves 25 are provided in the circumferential direction. Six low-pressure port grooves 26 are provided in the circumferential direction. The high-pressure port grooves 25 and the low-pressure port grooves 26 are positioned differently in the circumferential direction. The high-pressure port grooves 25 are provided at positions of 0°, 60°, 120°, 180°, 240°, and 300° in the circumferential direction. The low-pressure port grooves 26 are provided at positions of 30°, 90°, 150°, 210°, 270°, and 330°.

[0047] With the high-pressure port groove 25 connected to the two stator output ports 43A on the -X side, the low-pressure port groove 26 is connected to the two stator output ports 43B on the +X side. With the high-pressure port groove 25 connected to the two stator output ports 43B on the -X side, the low-pressure port groove 26 is connected to the two stator output ports 43A on the +X side.

[0048] As the rotating body 2A rotates, the state is switched between one in which the high-pressure port groove 25 is connected to the two stator output ports 43A on the -X side and the low-pressure port groove 26 is connected to the two stator output ports 43B on the +X side, and another in which the high-pressure port groove 25 is connected to the two stator output ports 43B on the -X side and the low-pressure port groove 26 is connected to the two stator output ports 43A on the +X side.

[0049] The stator output port 43A is connected to the output flow passage 54. Therefore, when the high-pressure port groove 25 and the two stator output ports 43A on the -X side are connected during rotation of the rotating body 2A, high-pressure hydraulic oil supplied from the body high-pressure port 51 to the high-pressure port groove 25 via the stator high-pressure port 41 is supplied to the two output flow passages 54 on the -X side. The high-pressure hydraulic oil supplied to the output flow passage 54 flows through the output flow passage 54 and is then supplied to the body output port 53. Furthermore, when the low-pressure port groove 26 and the two stator output ports 43A on the +X side are connected during rotation of the rotating body 2A, low-pressure hydraulic oil supplied from the body low-pressure port 52 to the low-pressure port groove 26 via the stator low-pressure port 42 is then supplied to the two output flow passages 54 on the +X side. The low-pressure hydraulic oil supplied to the output flow passage 54 flows through the output flow passage 54 and is then supplied to the body output port 53.

[0050] The stator output port 43B is not connected to the output flow path 54, but is blocked by the inner surface of the accommodation space 50. Therefore, when the high-pressure port groove 25 and the two stator output ports 43B on the −X side are connected during rotation of the rotating body 2A, the hydraulic oil in the high-pressure port groove 25 is not supplied to the output flow path 54. Furthermore, when the low-pressure port groove 26 and the two stator output ports 43B on the +X side are connected during rotation of the rotating body 2A, the hydraulic oil in the low-pressure port groove 26 is not supplied to the output flow path 54.

[0051] In this way, as the rotating body 2A rotates, a state in which the body high-pressure port 51 and the body output port 53 are connected via the high-pressure port groove 25 and the two stator output ports 43A on the -X side is switched to a state in which the body low-pressure port 52 and the body output port 53 are connected via the low-pressure port groove 26 and the two stator output ports 43A on the +X side is switched.

[0052] In the following description, the state in which the body high-pressure port 51 and the body output port 53 are connected via the high-pressure port groove 25 and the two stator output ports 43A on the -X side will be referred to as the high-pressure connection state, and the state in which the body low-pressure port 52 and the body output port 53 are connected via the low-pressure port groove 26 and the two stator output ports 43A on the +X side will be referred to as the low-pressure connection state.

[0053] In the high-pressure connection state, high-pressure hydraulic oil that has flowed into the body high-pressure port 51 flows out from the body output port 53. In the low-pressure connection state, low-pressure hydraulic oil that has flowed into the body low-pressure port 52 flows out from the body output port 53. As the rotating body 2A rotates, the high-pressure connection state and the low-pressure connection state are alternately switched.

[0054] In the present embodiment, the rotating body 2A rotates to change the time of a high-pressure connection state in which the body high-pressure port 51 and the body output port 53 are connected via the high-pressure port groove 25 and the stator output port 43A, and the time of a low-pressure connection state in which the body low-pressure port 52 and the body output port 53 are connected via the low-pressure port groove 26 and the stator output port 43A. The controller 10 controls the motor 61 to change the time of the high-pressure connection state and the time of the low-pressure connection state. The controller 10 controls the motor 61 to change the time of the high-pressure connection state and the time of the low-pressure connection state in accordance with the rotor angle (rotor angle) that indicates the rotation angle of the rotating body 2A.

[0055] In the following description, the time in the high voltage connection state will be referred to as the high voltage connection time, and the time in the low voltage connection state will be referred to as the low voltage connection time.

[0056] 9 is a diagram showing the relationship between the high-pressure connection state and the low-pressure connection state and time according to this embodiment. In FIG. 9, the horizontal axis represents time, and the vertical axis represents the pressure of the hydraulic oil flowing out from the body output port 53. As shown in FIG. 9, the high-pressure connection state and the low-pressure connection state are alternately switched by the rotation of the rotating body 2A.

[0057] In the following description, the time from the start of a first high-voltage connection state to the end of the next first low-voltage connection state will be referred to as one cycle [sec], and the reciprocal of one cycle will be referred to as the switching frequency [Hz]. One cycle is the sum of the first high-voltage connection time [sec] and the next first low-voltage connection time [sec]. The proportion of the high-voltage connection time in one cycle will be referred to as the duty ratio.

[0058] In this embodiment, one cycle is the time required for the rotating body 2A to rotate by 60°. The higher the rotation speed (rotational speed) of the rotating body 2A, the higher the switching frequency. The longer the high-voltage connection time, the higher the duty ratio. The duty ratio is adjusted by adjusting the high-voltage connection time or the low-voltage connection time. The controller 10 can adjust the switching frequency by controlling the motor 61 to control the rotational speed of the rotating body 2A. The controller 10 can adjust the duty ratio by controlling the motor 61 to control the high-voltage connection time or the low-voltage connection time.

[0059] Figure 10 is a diagram illustrating the operation of the rotary valve 1A according to this embodiment. The upper diagram in Figure 10 shows the relationship between the stator 4A and the high-pressure port groove 25 when the rotor 2A rotates, and corresponds to the cross-sectional view taken along line B1-B1 in Figure 2. The lower diagram in Figure 10 shows the relationship between the stator 4A and the low-pressure port groove 26 when the rotor 2A rotates, and corresponds to the cross-sectional view taken along line D1-D1 in Figure 2.

[0060] Figure 10 shows the state of the rotary valve 1A when the rotor angle, which indicates the rotation angle of the rotor 2A, changes to 0°, 10°, 20°, and 30°. In the example shown in Figure 10, the stator 4A does not rotate. The following description focuses on one high-pressure port groove 25A out of the six high-pressure port grooves 25. Similarly, the following description focuses on one low-pressure port groove 26A out of the six low-pressure port grooves 26.

[0061] 10 , when the rotor angle is 0°, high-pressure port groove 25A is blocked by the inner surface of stator 4A, and therefore hydraulic oil in high-pressure port groove 25A is not supplied to output flow path 54. Low-pressure port groove 26A is blocked by the inner surface of stator 4A, and therefore hydraulic oil in low-pressure port groove 26A is not supplied to output flow path 54.

[0062] When the rotor angle is 10°, although high-pressure port groove 25A is connected to stator output port 43B, stator output port 43B is blocked by the inner surface of accommodation space 50, and therefore hydraulic oil in high-pressure port groove 25A is not supplied to output flow path 54. On the other hand, low-pressure port groove 26A is connected to stator output port 43A, and therefore hydraulic oil in low-pressure port groove 26A is supplied to output flow path 54.

[0063] When the rotor angle is 20°, although high-pressure port groove 25A is connected to stator output port 43B, stator output port 43B is blocked by the inner surface of accommodation space 50, and therefore hydraulic oil in high-pressure port groove 25A is not supplied to output flow path 54. On the other hand, low-pressure port groove 26A is connected to stator output port 43A, and therefore hydraulic oil in low-pressure port groove 26A is supplied to output flow path 54.

[0064] When the rotor angle is 30°, high-pressure port groove 25A is blocked by the inner surface of stator 4A, so the hydraulic oil in high-pressure port groove 25 is not supplied to output flow path 54. Low-pressure port groove 26A is blocked by the inner surface of stator 4A, so the hydraulic oil in low-pressure port groove 26 is not supplied to output flow path 54.

[0065] Figure 11 is a diagram showing the relationship between the rotor angle, the area of ​​the hydraulic oil flow path, and the target value of the rotation speed of the rotor 2A according to this embodiment. In Figure 11, line L1 shows the relationship between the rotor angle and the overlapping area between the low-pressure port groove 26 and the stator output port 43A. Line L2 shows the relationship between the rotor angle and the overlapping area between the high-pressure port groove 25 and the stator output port 43A. Line L3 shows the relationship between the target rotation speed, which is the target value of the rotation speed of the rotor 2A, and the rotor angle.

[0066] As the rotor 2A rotates and the rotor angle changes, the overlapping area between the high-pressure port groove 25 and the stator output port 43A changes, and the overlapping area between the low-pressure port groove 26 and the stator output port 43A changes.

[0067] The overlapping area between the low-pressure port groove 26 and the stator output port 43A gradually increases when the rotor angle is in the range of 0° to 10°. The overlapping area between the low-pressure port groove 26 and the stator output port 43A is constant when the rotor angle is in the range of 10° to 20°. The overlapping area between the low-pressure port groove 26 and the stator output port 43A gradually decreases when the rotor angle is in the range of 20° to 30°. The low-pressure port groove 26 and the stator output port 43A do not overlap when the rotor angle is in the range of 30° to 60°.

[0068] When the rotor angle is in the range of 0° to 30°, the high-pressure port groove 25 and the stator output port 43A do not overlap. When the rotor angle is in the range of 30° to 40°, the overlapping area between the high-pressure port groove 25 and the stator output port 43A gradually increases. When the rotor angle is in the range of 40° to 50°, the overlapping area between the high-pressure port groove 25 and the stator output port 43A is constant. When the rotor angle is in the range of 50° to 60°, the overlapping area between the high-pressure port groove 25 and the stator output port 43A gradually decreases.

[0069] 11 , the controller 10 changes the rotation speed [rpm] of the rotor 2A according to the rotor angle. That is, the controller 10 changes the rotation speed of the rotor 2A for each of a plurality of rotor angles. By changing the rotation speed (rotational speed) of the rotor 2A for each of a plurality of rotor angles, the overlapping area between the high-pressure port groove 25 and the stator output port 43A and the overlapping area between the low-pressure port groove 26 and the stator output port 43A are each changed for each of the plurality of rotor angles.

[0070] In the example shown in FIG. 11 , when the rotor angle is in the range of 0° to 10°, the target rotation speed of the rotating body 2A is set to a value Ra. When the rotor angle is in the range of 10° to 20°, the target rotation speed of the rotating body 2A is set to a value Rb that is smaller than the value Ra. When the rotor angle is in the range of 20° to 40°, the target rotation speed of the rotating body 2A is set to a value Ra. When the rotor angle is in the range of 40° to 50°, the target rotation speed of the rotating body 2A is set to a value Rc that is smaller than the value Rb. When the rotor angle is in the range of 50° to 60°, the target rotation speed of the rotating body 2A is set to the value Ra. The controller 10 controls the motor 61 so that the rotating body 2A rotates at the target rotation speed.

[0071] Figure 12 is a diagram showing the relationship between time and the area of ​​the hydraulic oil flow path according to this embodiment. In Figure 12, line L4 shows the relationship between time and the overlapping area between the low-pressure port groove 26 and the stator output port 43A. Line L5 shows the relationship between time and the overlapping area between the high-pressure port groove 25 and the stator output port 43A. In Figure 12, 0 msec is the time when the rotor angle is 0°. The rotating body 2A rotates according to the target rotation speed described with reference to Figure 11.

[0072] In the range from 0 msec to 1 msec, the overlapping area between the low-pressure port groove 26 and the stator output port 43A gradually increases. In the range from 1 msec to 2 msec, the overlapping area between the low-pressure port groove 26 and the stator output port 43A remains constant. In the range from 2 msec to 3 msec, the overlapping area between the low-pressure port groove 26 and the stator output port 43A gradually decreases. In the range from 3 msec to 10 msec, there is no overlap between the low-pressure port groove 26 and the stator output port 43A.

[0073] In the range of 0 msec to 3 msec, the high-pressure port groove 25 and the stator output port 43A do not overlap. In the range of 3 msec to 4 msec, the overlapping area between the high-pressure port groove 25 and the stator output port 43A gradually increases. In the range of 4 msec to 9 msec, the overlapping area between the high-pressure port groove 25 and the stator output port 43A remains constant. In the range of 9 msec to 10 msec, the overlapping area between the high-pressure port groove 25 and the stator output port 43A gradually decreases.

[0074] 12, the high voltage duration is 7 msec in one cycle of 10 msec, so the duty ratio is 0.7. In this way, the duty ratio is adjusted by changing the rotation speed (rotational speed) of the rotor 2A for each of a plurality of rotor angles.

[0075] 13 is a diagram illustrating a method for determining the rotation speed of the rotor 2A according to this embodiment. As shown in FIG. 13, correlation data showing the relationship between the duty ratio, the rotation speed of the rotor 2A, and the switching frequency is calculated in advance and stored in the storage device 10B.

[0076] 13, line L6 shows the relationship between the target value of the rotation speed of the rotor 2A and the duty ratio when the low-pressure port groove 26 and the stator output port 43A overlap. Line L7 shows the relationship between the target value of the rotation speed of the rotor 2A and the duty ratio when the high-pressure port groove 25 and the stator output port 43A overlap. Line L8 shows the relationship between the switching frequency and the duty ratio.

[0077] As shown by line L6, when the rotation speed of the rotor 2A decreases when the low-pressure port groove 26 and the stator output port 43A overlap, the duty ratio decreases. As shown by line L7, when the rotation speed of the rotor 2A decreases when the high-pressure port groove 25 and the stator output port 43A overlap, the duty ratio increases. In the example shown in FIG. 13 , the switching frequency varies with the duty ratio, as shown by line L8. When the rotation speed of the rotor 2A is set so that the duty ratio is 0.5, the switching frequency increases. A desired duty ratio is input to the controller 10. The controller 10 determines the rotation speed for each angle of the rotor 2A and controls the motor 61 to obtain the switching frequency based on the input duty ratio and correlation data.

[0078] As described above, according to this embodiment, the stator 4A is supported by the body 5, and the stator output port 43 and the body output port 53 are connected via the output flow path 54 provided in the body 5. The high rigidity of the body 5 prevents the rotary valve 1A from being distorted or deformed by the pressure of the hydraulic oil. The suppression of distortion or deformation allows the assembly gap between the body 5 and the stator 4A to be reduced, thereby preventing leakage of the hydraulic oil. This improves the performance of the rotary valve 1A.

[0079] In this embodiment, the number of ports of the internal components disposed inside the body 5 is 12. Therefore, radial distortion and deformation of the rotary valve 1A due to the pressure of the hydraulic oil is suppressed.

[0080] Second Embodiment A second embodiment will be described below. In the following description, components that are the same as or equivalent to those in the first embodiment described above will be denoted by the same reference numerals, and descriptions of those components will be simplified or omitted.

[0081] Figures 14, 15, 16, and 17 are cross-sectional views showing a rotary valve 1B according to this embodiment. Figure 15 corresponds to a cross-sectional view taken along line B2-B2 in Figure 14. Figure 16 corresponds to a cross-sectional view taken along line C2-C2 in Figure 14. Figure 17 corresponds to an enlarged view of a portion of Figure 16.

[0082] The rotary valve 1B includes a control shaft 2B (rotating body), a rotor 3, a stator 4B, and a body 5. The body 5 has a body high-pressure port 51, a body low-pressure port 52, and a body output port 53. The stator 4B is disposed inside the body 5. The stator 4B has a stator output port 43 connected to the body output port 53 via an output flow passage 54 provided in the body 5. The rotor 3 is disposed inside the stator 4B. At least a portion of the rotor 3 is disposed between the outer surface of the control shaft 2B and the inner surface of the stator 4B. The rotor 3 has a rotor output port 33. The rotor 3 rotates about a rotation axis AX so that the stator output port 43 and the rotor output port 33 are switched between a connected state and a disconnected state. The rotation axis AX of the rotor 3 is parallel to the X-axis.

[0083] 18 is a perspective view showing a control shaft 2B according to this embodiment. The control shaft 2B has substantially the same structure as the rotating body 2A described in the first embodiment. The diameter of the control shaft 2B is smaller than the diameter of the rotating body 2A. The control shaft 2B is disposed inside the rotor 3. The operating rod portion 27 protrudes in the +X direction from the +X side end of the end rod portion 22.

[0084] High-pressure hydraulic oil from the body high-pressure port 51 is supplied to the high-pressure port groove 25. Low-pressure hydraulic oil from the body low-pressure port 52 is supplied to the low-pressure port groove 26. The high-pressure port groove 25 and the low-pressure port groove 26 are provided at different positions in the circumferential direction. The high-pressure port groove 25 and the low-pressure port groove 26 are provided at different positions in the axial direction.

[0085] 19 is a perspective view showing the rotor 3 according to this embodiment. The rotor 3 is long in the X-axis direction. The rotor 3 has a cylindrical portion 30, a rotor high-pressure port 31, a rotor low-pressure port 32, a rotor output port 33, and an operating rod portion 34.

[0086] The cylindrical portion 30 is disposed around at least a portion of the control shaft 2B. The cylindrical portion 30 is disposed around the central rod portion 20, the end rod portions 21 and 22, the high-pressure recess 23, and the low-pressure recess 24. An opening is provided at the +X side end of the cylindrical portion 30. The central rod portion 20 is inserted into the cylindrical portion 30 through the opening at the +X side end of the cylindrical portion 30. The -X side end of the cylindrical portion 30 is closed by a wall portion. The operating rod portion 34 protrudes to the -X side from the -X side end of the cylindrical portion 30.

[0087] The rotor high-pressure port 31 is provided at the end of the cylindrical portion 30 on the -X side. The rotor high-pressure port 31 is a hole that penetrates the outer surface and inner surface of the cylindrical portion 30. In this embodiment, the rotor high-pressure port 31 is circular. Six rotor high-pressure ports 31 are provided at equal intervals in the circumferential direction. In the X-axis direction, the position of the rotor high-pressure port 31 and the position of the high-pressure recess 23 coincide. The hydraulic oil that passes through the rotor high-pressure port 31 is supplied to the high-pressure recess 23.

[0088] The rotor low pressure port 32 is provided at the end of the cylindrical portion 30 on the +X side. The rotor low pressure port 32 is a hole that penetrates the outer surface and inner surface of the cylindrical portion 30. In this embodiment, the rotor low pressure port 32 has a rectangular shape that is long in the X-axis direction. Six rotor low pressure ports 32 are provided at equal intervals around the circumference. In the X-axis direction, the positions of the rotor low pressure ports 32 and the low-pressure recess 24 coincide with each other. The hydraulic oil that passes through the rotor low pressure ports 32 is supplied to the low-pressure recess 24.

[0089] The rotor output port 33 is provided between the rotor high-pressure port 31 and the rotor low-pressure port 32 in the X-axis direction. The rotor output port 33 is a hole that penetrates the outer surface and inner surface of the cylindrical portion 30. In this embodiment, the rotor output port 33 has an elliptical shape that is long in the X-axis direction. The size of the rotor output port 33 is smaller than the size of the rotor high-pressure port 31 and the size of the rotor low-pressure port 32. Eight rotor output ports 33 are provided in the X-axis direction. Twelve rotor output ports 33 are provided at equal intervals in the circumferential direction. The eight rotor output ports 33 arranged in the X-axis direction are arranged at equal positions relative to each other in the circumferential direction. In other words, the eight rotor output ports 33 arranged in the X-axis direction are arranged linearly in the X-axis direction.

[0090] In the X-axis direction, the positions of the four rotor output ports 33 on the −X side of the center of the cylindrical portion 30 coincide with the positions of the high-pressure port grooves 25. The four rotor output ports 33 on the −X side overlap with the high-pressure port grooves 25 in the X-axis direction.

[0091] In the X-axis direction, the positions of the four rotor output ports 33 on the +X side of the center of the cylindrical portion 30 coincide with the positions of the low-pressure port grooves 26. The four rotor output ports 33 on the +X side overlap with the low-pressure port grooves 26 in the X-axis direction.

[0092] 17, the dimension of the high-pressure port groove 25 is equal to the dimension of the rotor output port 33 in the circumferential direction. The dimension of the low-pressure port groove 26 is equal to the dimension of the rotor output port 33 in the circumferential direction.

[0093] Figure 20 is a perspective view showing a stator 4B according to this embodiment. The stator 4B has substantially the same structure as the stator 4B described in the first embodiment. As shown in Figure 17, the dimension of the stator output port 43 in the circumferential direction is larger than the dimension of the high-pressure port groove 25. The dimension of the stator output port 43 in the circumferential direction is larger than the dimension of the low-pressure port groove 26. The dimension of the stator output port 43 in the circumferential direction is larger than the dimension of the rotor output port 33.

[0094] The cylindrical portion 40 is disposed around the cylindrical portion 30. An opening is provided at each of the +X side end and the −X side end of the cylindrical portion 40. The central rod portion 20 and the cylindrical portion 30 are inserted into the inside of the cylindrical portion 40 through the opening at the +X side end or the opening at the −X side of the cylindrical portion 40.

[0095] In the X-axis direction, the position of the stator high-pressure port 41 coincides with the position of the rotor high-pressure port 31. The hydraulic oil that has passed through the stator high-pressure port 41 is supplied to the high-pressure recess 23 via the rotor high-pressure port 31.

[0096] In the X-axis direction, the position of the stator low-pressure port 42 coincides with the position of the rotor low-pressure port 32. The hydraulic oil that passes through the stator low-pressure port 42 is supplied to the low-pressure recess 24 via the rotor low-pressure port 32.

[0097] The two stator output ports 43 on the -X side are an example of first stator output ports that can be connected to the high-pressure port groove 25 via the four rotor output ports 33 on the -X side. The two stator output ports 43 on the -X side are not connected to the low-pressure port groove 26. The two stator output ports 43 on the +X side are an example of second output ports that can be connected to the low-pressure port groove 26 via the four rotor output ports 33 on the +X side. The two stator output ports 43 on the +X side are not connected to the high-pressure port groove 25.

[0098] The body 5 has substantially the same structure as the body 5 described in the first embodiment. The control shaft 2B, rotor 3, and stator 4B are accommodated inside an accommodation space 50 of the body 5. The outer surface of the stator 4B faces the inner surface of the accommodation space 50. The outer surface of the stator 4B contacts the inner surface of the accommodation space 50. With the control shaft 2B, rotor 3, and stator 4B arranged inside the accommodation space 50, the opening on the -X side of the accommodation space 50 is covered with a cover 6, and the opening on the +X side of the accommodation space 50 is covered with a cover 7. The operating rod portion 27 protrudes on the +X side from an opening provided in the center of the cover 7. The operating rod portion 34 protrudes on the -X side from an opening provided in the center of the cover 6.

[0099] High-pressure hydraulic oil supplied from the body high-pressure port 51 to the stator high-pressure port 41 is supplied to the high-pressure recess 23 via the rotor high-pressure port 31. The high-pressure hydraulic oil supplied to the high-pressure recess 23 flows through the high-pressure port groove 25, and can then flow into the two stator output ports 43 on the −X side of the cylindrical portion 40 via the four rotor output ports 33 on the −X side of the cylindrical portion 30.

[0100] Low-pressure hydraulic oil supplied from body low-pressure port 52 to stator low-pressure port 42 is supplied to low-pressure recess 24 via rotor low-pressure port 32. After flowing through low-pressure port groove 26, hydraulic oil supplied to low-pressure recess 24 can flow into two stator output ports 43 on the +X side of cylindrical portion 40 via four rotor output ports 33 on the +X side of cylindrical portion 30.

[0101] FIG. 21 is a schematic diagram showing a rotary valve 1B according to this embodiment. A motor 62 is connected to the operating rod portion 34 of the rotor 3. The rotor 3 rotates inside the stator 4B due to the rotational force generated by the motor 62. A motor 61 is connected to the operating rod portion 27 of the control shaft 2B. The control shaft 2B rotates a predetermined angle about the rotation axis AX due to the power generated by the motor 61. A controller 10 controls each of the motors 61 and 62. The control shaft 2B may be rotated manually. The angle of the control shaft 2B can be adjusted as desired. With the control shaft 2B stopped, hydraulic oil flows through the rotary valve 1B. The angle of the control shaft 2B may be changed while hydraulic oil is flowing through the rotary valve 1B.

[0102] As shown in Figure 17, twelve stator output ports 43 are provided in the circumferential direction. Six output flow paths 54 are provided in the circumferential direction. The radially inner openings of the output flow paths 54 are provided at equal intervals in the circumferential direction. The stator output ports 43 include a stator output port 43A connected to the output flow paths 54 and a stator output port 43B that is not connected to the output flow paths 54 and is closed by the inner surface of the accommodation space 50. The stator output ports 43A and the stator output ports 43B are provided alternately in the circumferential direction.

[0103] Six high-pressure port grooves 25 are provided circumferentially. Twelve rotor output ports 33 are provided circumferentially. The rotor 3 rotates about the rotation axis AX. As shown in FIG. 17 , when the rotor 3 rotates, the rotor output ports 33 include a rotor output port 33B connected to the high-pressure port groove 25 and a rotor output port 33A not connected to the high-pressure port groove 25. The rotor output ports 33A and the rotor output port 33B are arranged alternately in the circumferential direction. Note that when the high-pressure port groove 25 is connected to the rotor output port 33B, the rotor output port 33A is not connected to the high-pressure port groove 25. In other words, as the rotor 3 rotates, switching is performed between a state in which the high-pressure port groove 25 is not connected to the rotor output port 33A but the high-pressure port groove 25 is connected to the rotor output port 33B, and a state in which the high-pressure port groove 25 is not connected to the rotor output port 33B but the high-pressure port groove 25 is connected to the rotor output port 33A.

[0104] Furthermore, when the rotor output port 33A and the stator output port 43A are connected during rotation of the rotor 3, the rotor output port 33B and the stator output port 43B are connected. When the rotor output port 33A and the stator output port 43B are connected, the rotor output port 33B and the stator output port 43A are connected. In other words, as the rotor 3 rotates, a state in which the rotor output port 33A and the stator output port 43A are connected and a state in which the rotor output port 33A and the stator output port 43B are connected are switched. A state in which the rotor output port 33B and the stator output port 43B are connected and a state in which the rotor output port 33B and the stator output port 43A are connected are switched.

[0105] The stator output port 43B is not connected to the output flow path 54 but is blocked by the inner surface of the accommodation space 50. Therefore, when the rotor output port 33A and the stator output port 43B are connected, the hydraulic oil supplied to the rotor output port 33A from the high-pressure port groove 25 or the low-pressure port groove 26 is not supplied to the output flow path 54. When the rotor output port 33B and the stator output port 43B are connected, the hydraulic oil supplied to the rotor output port 33B from the high-pressure port groove 25 or the low-pressure port groove 26 is not supplied to the output flow path 54.

[0106] Figure 22 is a diagram illustrating the operation of the rotary valve 1B according to this embodiment. The upper diagram in Figure 22 illustrates the operation of the rotary valve 1B when hydraulic oil is supplied from the body high-pressure port 51 to the high-pressure port groove 25 via the stator high-pressure port 41 and the rotor high-pressure port 31, and corresponds to the cross-sectional view taken along line B2-B2 in Figure 14. The lower diagram in Figure 22 illustrates the operation of the rotary valve 1B when hydraulic oil is supplied from the body low-pressure port 52 to the low-pressure port groove 26 via the stator low-pressure port 42 and the rotor low-pressure port 32, and corresponds to the cross-sectional view taken along line D2-D2 in Figure 14. The following description focuses on one of the six high-pressure port grooves 25, the high-pressure port groove 25A. Similarly, the following description focuses on one of the six low-pressure port grooves 26, the low-pressure port groove 26A.

[0107] 22 shows the state of the rotary valve 1B when the rotor angle, which indicates the angle of the rotor 3, changes to 0°, 10°, 20°, and 30°. In the example shown in FIG. 22, the control shaft 2B and the stator 4B do not rotate.

[0108] As shown in Figure 22, when the rotor angle is 0°, none of the twelve rotor output ports 33 are connected to the stator output port 43. As shown in Figure 22, when the rotor angle is 0°, on the high-pressure side, the high-pressure port groove 25A is connected to the rotor output port 33B. Because the rotor output port 33B is blocked by the inner surface of the stator 4B, the hydraulic oil in the high-pressure port groove 25A is not supplied to the output flow path 54. Also, on the low-pressure side, the low-pressure port groove 26A is connected to the rotor output port 33A. Because the rotor output port 33A is blocked by the inner surface of the stator 4B, the hydraulic oil in the low-pressure port groove 26A is not supplied to the output flow path 54.

[0109] When the rotor angle is 10°, on the high-pressure side, the rotor output port 33A and the stator output port 43A are connected, and the high-pressure port groove 25A is connected to the stator output port 43B via the rotor output port 33B. The stator output port 43B is not connected to the output flow passage 54 but is blocked by the inner surface of the accommodation space 50, so the hydraulic oil in the high-pressure port groove 25A is not supplied to the output flow passage 54. On the other hand, on the low-pressure side, the low-pressure port groove 26A is connected to the rotor output port 33A, and the rotor output port 33A is connected to the stator output port 43A, so the hydraulic oil in the low-pressure port groove 26A is supplied to the output flow passage 54.

[0110] When the rotor angle is 20°, on the high-pressure side, high-pressure port groove 25A is connected to rotor output port 33A, which is connected to stator output port 43A, and therefore hydraulic oil in high-pressure port groove 25A is supplied to output flow path 54. On the other hand, on the low-pressure side, rotor output port 33A and stator output port 43A are connected, and low-pressure port groove 26A is connected to stator output port 43B via rotor output port 33B. Since stator output port 43B is not connected to output flow path 54 and is blocked by the inner surface of accommodation space 50, hydraulic oil in low-pressure port groove 26A is not supplied to output flow path 54.

[0111] When the rotor angle is 30°, on the high-pressure side, high-pressure port groove 25A is connected to rotor output port 33A, but rotor output port 33A is blocked by the inner surface of stator 4B, so hydraulic oil in high-pressure port groove 25 is not supplied to output flow path 54. Also, on the low-pressure side, low-pressure port groove 26A is connected to rotor output port 33B, but rotor output port 33B is blocked by the inner surface of stator 4B, so hydraulic oil in low-pressure port groove 26A is not supplied to output flow path 54.

[0112] In this way, rotation of the rotor 3 switches between a state in which hydraulic oil supplied from the body high-pressure port 51 to the high-pressure port groove 25 is supplied to the output flow path 54 and a state in which hydraulic oil supplied from the body low-pressure port 52 to the low-pressure port groove 26 is supplied to the output flow path 54. The hydraulic oil supplied from the body high-pressure port 51 to the high-pressure port groove 25 flows through the output flow path 54 and then flows out from the body output port 53. The hydraulic oil supplied from the body low-pressure port 52 to the low-pressure port groove 26 flows through the output flow path 54 and then flows out from the body output port 53. In other words, when high-pressure hydraulic oil is supplied to the body high-pressure port 51 and low-pressure hydraulic oil is supplied to the body low-pressure port 52, rotation of the rotor 3 switches between a state in which high-pressure hydraulic oil flows out from the body output port 53 and a state in which low-pressure fluid flows out from the body output port 53.

[0113] Fig. 23 is a diagram showing the relationship between the rotor angle and the area of ​​the high-pressure side flow path for hydraulic oil according to this embodiment, illustrating the relative relationship between one high-pressure port groove 25A of the six high-pressure port grooves 25, one stator output port 43A of the twelve stator output ports 43, and one rotor output port 33A of the twelve rotor output ports 33, as shown in Fig. 22.

[0114] In FIG. 23 , line La indicates the flow path area of ​​the high-pressure port groove 25A. The flow path area of ​​the high-pressure port groove 25A is constant. Line Lb indicates the overlapping area between the high-pressure port groove 25A and the rotor output port 33A. As shown in FIG. 22 , when the rotor angle is in the range of 0° to 10°, the high-pressure port groove 25A and the rotor output port 33A are not connected, so the overlapping area indicated by line Lb is zero. As the rotor angle approaches 20°, a portion of the high-pressure port groove 25A overlaps with the rotor output port 33A, and when the rotor angle is 30°, the overlapping area between the high-pressure port groove 25A and the rotor output port 33A is maximized. Line Lc indicates the overlapping area between the rotor output port 33A and the stator output port 43A. 22 , when the rotor angle is 0°, the rotor output port 33A and the stator output port 43A are not connected, and therefore the overlapping area indicated by line Lc is zero. As the rotor angle gradually increases from 0°, a portion of the rotor output port 33A overlaps with the stator output port 43A, and when the rotor angle reaches 10°, the overlapping area between the rotor output port 33A and the stator output port 43A reaches a maximum. When the rotor angle is in the range of 10° to 20°, the overlapping area between the rotor output port 33A and the stator output port 43A remains maximum. As the rotor angle gradually increases from 20°, the overlapping area between the rotor output port 33A and the stator output port 43A gradually decreases, and when the rotor angle reaches 30°, the overlapping area between the rotor output port 33A and the stator output port 43A becomes zero.

[0115] Hydraulic oil supplied from the body high-pressure port 51 to the high-pressure port groove 25A passes through the overlapping portion between the high-pressure port groove 25A and the rotor output port 33A, and then passes through the overlapping portion between the rotor output port 33A and the stator output port 43A, before being supplied to the output flow passage 54. Therefore, the minimum flow passage area of ​​the hydraulic oil supplied from the high-pressure port groove 25A to the output flow passage 54 is represented by line Ld. That is, the flow passage area of ​​the hydraulic oil at each of multiple rotor angles is represented by the smallest area among lines La, Lb, and Lc. At rotor angles where the flow passage area represented by line Ld is greater than zero, the hydraulic oil supplied from the body high-pressure port 51 to the high-pressure port groove 25A is supplied to the output flow passage 54 and flows out of the body output port 53.

[0116] As the control shaft 2B rotates and the angle of the control shaft 2B is changed, the overlapping area between the high-pressure port groove 25 and the rotor output port 33, and the overlapping area between the low-pressure port groove 26 and the rotor output port 33 are each changed for each of multiple rotor angles.

[0117] Furthermore, by rotating the control shaft 2B and changing the angle of the control shaft 2B, the ratio between the rotor angle range in which the flow path area indicated by line Ld is zero and the rotor angle range in which it is greater than zero is adjusted during one rotation of the rotor 3. By changing the angle of the control shaft 2B, the ratio between the non-connection time and the connection time between the high-pressure port groove 25 and the body output port 53 is adjusted.

[0118] That is, by changing the angle of control shaft 2B, the time for a high-pressure connection state in which body high-pressure port 51 and body output port 53 are connected via high-pressure port groove 25, four rotor output ports 33 on the −X side, and two stator output ports 43 on the −X side, and the time for a low-pressure connection state in which body low-pressure port 52 and body output port 53 are connected via low-pressure port groove 26, four rotor output ports 33 on the +X side, and two stator output ports 43 on the +X side, are changed, respectively. That is, by changing the angle of control shaft 2B, the duty ratio is changed.

[0119] 24 and 25 are diagrams showing the relationship between the rotor angle and the area of ​​the flow path for the high-pressure hydraulic oil according to this embodiment.

[0120] As shown in Figures 24 and 25, the high-pressure connection time is adjusted by adjusting the rotational position of the control shaft 2B in the rotational direction. Figure 24 shows the relationship between the rotor angle and the area of ​​the high-pressure flow path for hydraulic oil when the control shaft 2B is rotated clockwise by approximately 5° in the diagram shown in the upper part of Figure 22. Figure 25 shows the relationship between the rotor angle and the area of ​​the high-pressure flow path for hydraulic oil when the control shaft 2B is rotated counterclockwise by approximately 5° in the diagram shown in the upper part of Figure 22. As shown in Figure 24, when the control shaft 2B is rotated clockwise by approximately 5°, line Lb, which indicates the overlapping area between the high-pressure port groove 25A and the rotor output port 33A, shifts to line Lbu, and the high-pressure connection time becomes longer. As shown in Figure 25, when the control shaft 2B is rotated counterclockwise by approximately 5°, line Lb, which indicates the overlapping area between the high-pressure port groove 25A and the rotor output port 33A, shifts to line Lbd, and the high-pressure connection time becomes shorter.

[0121] 23, 24, and 25 show the relationship between the rotor angle and the area of ​​the flow path for hydraulic oil on the high-pressure side. The relationship between the rotor angle and the area of ​​the flow path for hydraulic oil on the low-pressure side is also similar. The low-pressure connection time is adjusted by adjusting the rotational position of the control shaft 2B.

[0122] As described above, in this embodiment as well, the stator 4B is supported by the body 5, and the stator output port 43 and the body output port 53 are connected via the output flow path 54 provided in the body 5. The high rigidity of the body 5 prevents the rotary valve 1B from being distorted or deformed by the pressure of the hydraulic oil. The suppression of distortion or deformation allows the assembly gap between the body 5 and the stator 4B to be reduced, thereby preventing leakage of the hydraulic oil. This improves the performance of the rotary valve 1B.

[0123] In this embodiment, the number of ports of the internal components arranged inside the body 5 is 12. Therefore, radial distortion and deformation of the rotary valve 1B due to the pressure of the hydraulic oil is suppressed.

[0124] Third Embodiment A third embodiment will now be described. In the following description, components that are the same as or equivalent to those in the first embodiment described above will be denoted by the same reference numerals, and descriptions of those components will be simplified or omitted.

[0125] 26 and 27 are diagrams illustrating an example of use of the rotary valve 1 (1A, 1B) according to this embodiment. As shown in FIG. 26, the rotary valve 1 can be used as a flow booster. A high-pressure hydraulic oil source pH is connected to a body high-pressure port 51, and a low-pressure hydraulic oil source pL is connected to a body low-pressure port 52. Rotation of the rotor 3 switches between a state in which high-pressure hydraulic oil flows out of the body output port 53 and a state in which low-pressure hydraulic oil flows out. The hydraulic oil flowing out of the body output port 53 is supplied to the load 12 via the inertia pipe 11 and then discharged to the tank 13. An accumulator 14 is connected to the flow path between the inertia pipe 11 and the load 12.

[0126] Rotation of the rotating body 2A or the control shaft 2B adjusts the ratio between the high-pressure connection time, which indicates the connection time between the high-pressure hydraulic oil source pH and the body output port 53, and the low-pressure connection time, which indicates the connection time between the low-pressure hydraulic oil source pL and the body output port 53. In other words, the duty ratio is adjusted. For example, when the pressure of the hydraulic oil from the low-pressure hydraulic oil source pL is 0 MPa and the pressure of the hydraulic oil from the high-pressure hydraulic oil source pH is 10 MPa, if the ratio of the high-pressure connection time to the low-pressure connection time is [50:50], hydraulic oil at a pressure of 5 MPa is theoretically supplied to the load 12, and if the ratio is [70:30], hydraulic oil at a pressure of 7 MPa is theoretically supplied to the load 12.

[0127] 27 , the rotary valve 1 can be used as a pressure booster. An inertia pipe 11 is connected to a hydraulic oil source pM, and the rotary valve 1 is disposed between the inertia pipe 11 and a load 12. The inertia pipe 11 is connected to a body output port 53, the body high-pressure port 51 is connected to a load 12, and the body low-pressure port 52 is connected to a tank 13. By changing the state in which the body output port 53 and the body low-pressure port 52 are connected to each other, and the state in which the body output port 53 and the body high-pressure port 51 are connected, the pressure of hydraulic oil from the inertia pipe 11 flows into the accumulator 14, and pressure accumulates in the accumulator 14, even if the pressure of the accumulator 14 is higher than the pressure of the hydraulic oil source pM.

[0128] 1...rotary valve, 1A...rotary valve, 1B...rotary valve, 2A...rotating body, 2B...control shaft (rotating body), 3...rotor, 4A...stator, 4B...stator, 5...body, 6...cover, 7...cover, 8...plug, 9...plug, 10...controller, 10A...processor, 10B...storage device, 10C...input / output interface, 11...inertia piping, 12...load, 13...tank, 14...accumulator, 20...central rod portion, 21...end rod portion, 22...end rod portion, 23...high pressure recess, 24...low pressure recess, 25...high pressure port groove, 25A...high pressure port groove, 26...low pressure port groove, 26A...Low pressure port groove, 27...Operating rod portion, 30...Cylindrical portion, 31...Rotor high pressure port, 32...Rotor low pressure port, 33...Rotor output port, 33A...Rotor output port, 33B...Rotor output port, 34...Operating rod portion, 40...Cylindrical portion, 41...Stator high pressure port, 42...Stator low pressure port, 43...Stator output port, 43A...Stator output port, 43B...Stator output port, 44...Flange portion, 50...Accommodation space, 51...Body high pressure port, 52...Body low pressure port, 53...Body output port, 54...Output flow path, 55...Connection flow path, 61...Motor, 62...Motor, AX...Rotating shaft

Claims

1. A rotary valve system comprising: a body having a body high-pressure port, a body low-pressure port, and a body output port; a stator arranged inside the body and having a stator output port connected to the body output port via an output flow path provided in the body; a rotor arranged inside the stator and having a high-pressure port groove to which hydraulic oil is supplied from the body high-pressure port, and a low-pressure port groove located at a position different from the high-pressure port groove in the circumferential direction to which hydraulic oil is supplied from the body low-pressure port; and a controller for controlling the rotation of the rotor, wherein the controller rotates the rotor so as to change each of the time of a high-pressure connection state in which the body high-pressure port and the body output port are connected via the high-pressure port groove and the stator output port, and the time of a low-pressure connection state in which the body low-pressure port and the body output port are connected via the low-pressure port groove and the stator output port.

2. The rotary valve system according to claim 1, wherein the outer surface of the rotor faces the inner surface of the stator, and the controller rotates the rotor so that the overlapping area between the high-pressure port groove and the stator output port and the overlapping area between the low-pressure port groove and the stator output port are both changed for each of a plurality of rotor angles.

3. The rotary valve system according to claim 2, wherein the high-pressure connection state and the low-pressure connection state are switched by the rotation of the rotor, and the controller changes the rotation speed of the rotor for each of a plurality of rotor angles to adjust a duty ratio indicating the proportion of time spent in the high-pressure connection state in one cycle which is the sum of time spent in the high-pressure connection state and time spent in the low-pressure connection state.

4. The rotary valve system according to claim 3, wherein the controller controls the rotational speed to adjust a switching frequency, which is the reciprocal of one period.

5. The rotary valve system according to claim 3, wherein the high-pressure port groove and the low-pressure port groove are provided at different positions in the axial direction, and the stator output ports include a first stator output port connectable to the high-pressure port groove and a second stator output port connectable to the low-pressure port groove.

6. The rotary valve system according to claim 1, further comprising: a rotor at least a portion of which is disposed between an outer surface of the rotating body and an inner surface of the stator, the rotor having a rotor output port; the controller rotates the rotor so that the stator output port and the rotor output port are switched between a connected state and a disconnected state; and the controller rotates the rotating body so that the overlapping area between the high-pressure port groove and the rotor output port, and the overlapping area between the low-pressure port groove and the rotor output port, are each changed for each of a plurality of rotor angles.

7. The rotary valve system according to claim 1, wherein the stator is accommodated in an accommodation space provided in the body, and an outer surface of the stator faces an inner surface of the accommodation space.

8. The rotary valve system according to claim 6, wherein the high pressure port groove and the low pressure port groove are provided at different positions in the axial direction, and the stator output ports include a first stator output port connectable to the high pressure port groove via the rotor output port, and a second stator output port connectable to the low pressure port groove via the rotor output port.

9. The rotary valve system according to claim 1, wherein the number of the stator output ports provided in the circumferential direction is an even number of 10 or more.

10. The rotary valve system according to claim 1, wherein six of the output flow passages are provided in the circumferential direction, and twelve of the stator output ports are provided in the circumferential direction.

11. The rotary valve system according to claim 6, wherein six of the output flow passages are provided in the circumferential direction, twelve of the stator output ports are provided in the circumferential direction, and twelve of the rotor output ports are provided in the circumferential direction.

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