JP2009179153A - Rotary valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate manufacture in a rotary valve composed of a sleeve and a spool freely rotatably engaged in the sleeve to control a hydraulic actuator. <P>SOLUTION: The rotary valve comprises the sleeve 60, and the spool 70 freely rotatably engaged in the sleeve 60 for controlling the hydraulic actuator. For feeding and discharging hydraulic oil to/from the hydraulic actuator, actuator oil passage holes 61 and 63 penetrating the sleeve 60 are open in an inner circumferential surface of the sleeve 60 in such a way that the hole diameter is constant where they are located on the inner circumferential side of the sleeve 60. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rotary valve configured to control a hydraulic actuator by a sleeve and a spool that is rotatably fitted in the sleeve.

  The above-described rotary valve has an actuator oil passage hole penetrating the sleeve, and when the spool is rotated, the actuator oil passage is communicated to the pump side or the tank side by the oil passage of the spool to the hydraulic actuator. It is configured to supply and discharge pressure oil.

Conventionally, for example, there has been a control valve described in Patent Document 1 as this type of rotary valve.
The control valve described in Patent Document 1 includes a sleeve, a rotary pool as a spool, and a first port and a second port as actuator oil passage holes penetrating the sleeve.
The first port and the second port include a vertical groove provided on the inner peripheral side of the sleeve, and open to the inner peripheral surface of the sleeve via the vertical groove.

JP 2004-352155 A

When a rotary valve is obtained by adopting the above-described conventional technology, advanced and special processing technology and processing equipment are required.
That is, when the conventional technology is adopted, the oil passage hole for the actuator provided in the sleeve has a hole shape in which the hole diameter expands on the inner peripheral side of the sleeve and opens in the inner peripheral surface of the sleeve in this expanded state. Therefore, in order to provide the oil passage hole for the actuator, a hole forming process performed from the inner peripheral side of the sleeve has been required.

  An object of the present invention is to obtain a rotary valve that is easy to manufacture.

The first aspect of the present invention is a rotary valve configured to control a hydraulic actuator by a sleeve and a spool that is rotatably fitted in the sleeve.
The oil passage hole for the actuator, which is provided in the sleeve so as to be connected to the hydraulic actuator so as to supply and discharge the pressure oil to and from the hydraulic actuator, has a constant hole diameter at a portion located on the inner peripheral side of the sleeve. In the state, it is opened on the inner peripheral surface of the sleeve.

  According to the configuration of the first aspect of the invention, the actuator oil passage hole provided in the sleeve has a hole shape opened to the inner peripheral surface of the sleeve with a constant hole diameter at a portion located on the inner peripheral side of the sleeve. In order to provide the actuator oil passage hole, if the hole forming process performed from the outer peripheral side of the sleeve is performed, the hole forming process performed from the inner peripheral side can be omitted.

  Therefore, a rotary valve can be obtained easily and inexpensively only by providing a technique and processing equipment that do not require the inner peripheral side machining, as compared with a case in which the sleeve is formed with holes from the inner peripheral side.

In the second invention, a valve casing for housing the sleeve is connected to the actuator casing of the hydraulic actuator,
An induction oil passage through which leaked oil generated inside the valve casing flows into the hydraulic actuator is provided across the valve casing and the actuator casing.

  According to the configuration of the second aspect of the present invention, the leak oil generated in the valve casing can be effectively used for the hydraulic actuator, for example, by flowing into the hydraulic actuator through the induction oil passage and replenishing the hydraulic actuator for oil immersion. .

  Therefore, the rotary valve integrated with the hydraulic actuator can be obtained in an advantageous state in which the leak oil of the rotary valve can be effectively used for the hydraulic actuator.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall side view of a riding type rice transplanter. As shown in this figure, this riding type rice transplanter is provided in a pair of left and right steering operations and driveable front wheels 1 and 1, a pair of left and right driveable rear wheels 2 and 2, and a front part of the vehicle body. A self-propelled vehicle having an engine 3 and a driver's seat 4 provided at the rear part of the vehicle body is provided, and a seedling planting device 10 connected to the rear part of the vehicle body frame 5 of the self-propelled vehicle via a link mechanism 6 is provided. .

This riding type rice transplanter performs a plurality of seedling planting operations.
In other words, the link mechanism 6 is swung up and down with respect to the vehicle body frame 5 by the hydraulic cylinder 7 and the grounding float 12 provided at the lower portion of the planting machine body 11 with the seedling planting device 10 is in a descending work state in contact with the rice field. Then, the grounding float 12 is moved up and down to the non-working state in which the grounding float 12 is lifted from the surface. When the seedling planting device 10 is moved down and the self-propelled vehicle is driven, the seedling planting device 10 is driven by the output of the engine 3 being transmitted through the rotary shaft 8 and is planted at the rear of the planting machine 11. The seedlings are planted on the rice field by the seedling planting mechanism 13 arranged side by side in the apparatus. That is, each seedling planting mechanism 13 includes a pair of planting arms 13a and 13a, and one planting arm 13a and the other planting arm 13a are alternately separated from the mat-like seedling on the seedling mount 14 by seedling planting claws. The block seedlings are cut out and taken out, and the taken out block seedlings are transported down and planted to plant the seedlings on the land surface that has been leveled by the ground float 12. The seedling mount 14 is reciprocated in the lateral direction of the seedling planting device in conjunction with the seedling planting movement of the seedling planting mechanism 13, and the removal of the block seedling by each seedling planting mechanism 13 is performed from one end side in the lateral direction of the mat-like seedling. The mat-like seedlings are transferred to the seedling planting mechanism 13 in the lateral direction with respect to the seedling planting mechanism 13 so as to be sequentially performed toward the other end side.

The self-propelled vehicle includes a steering handle 20 provided in front of the driver's seat 4 and a knuckle arm 21 (see FIG. 3) as a steering operation portion of the pair of left and right front wheels 1, 1. A power steering device 22 that is interlocked is provided, and the steering operation is performed by rotating the steering handle 20.
In other words, when the steering handle 20 is rotated, the power steering device 22 is activated to move the pair of left and right front wheels 1 and 1 around the steering axis of the vehicle body in the vertical direction corresponding to the rotation direction of the steering handle 20. The steering operation is performed in the steering direction in the direction corresponding to the rotation angle of the steering handle 20.

  FIG. 2 is a side view of a portion of the self-propelled vehicle where the power steering device 22 is disposed. FIG. 3 is a plan view of the power steering device 22. As shown in these drawings, the power steering device 22 includes a torque generator 40 provided on an upper portion of a transmission case 23 that constitutes a front portion of the vehicle body frame 5, and an input shaft 41 of the torque generator 40. The output shaft 42 is connected to the pair of right and left by a rotating shaft 24 that is linked to the rotating support shaft 20a and a rotating shaft 26 that has an upper end connected to the output shaft 42 of the torque generator 40 so as to be integrally rotatable. And an interlocking mechanism 25 interlocking with the knuckle arm 21 of the front wheels 1 and 1.

  FIG. 4 is a diagram of the interlock mechanism 25. As shown in FIG. 2 and FIG. 2, 3, the interlock mechanism 25 includes the rotation shaft 26, a rotation gear 27 provided at the lower end portion of the rotation shaft 26 so as to be integrally rotatable, and the rotation gear 27. The tie rod 28 meshed with the rack gear portion 28a and the interlocking rod 29 connected to both ends of the tie rod 28 are provided. The interlock rod 29 on the left end side of the tie rod 28 connects the tie rod 28 and the knuckle arm 21 of the left front wheel 1. The interlock rod 29 on the right end side of the tie rod 28 connects the tie rod 28 and the knuckle arm 21 of the right front wheel 1.

  The transmission case 23 supports the front wheel 1 so as to be steerable and drivable via a front wheel drive case 30 extending from a lateral side wall portion thereof. The transmission case 23 includes a hydrostatic continuously variable transmission 31 connected to the front end of the transmission case 23, and the driving force transmitted from the output shaft 3 a of the engine 3 by the transmission belt 32 is transmitted to the hydrostatic continuously variable. The transmission 31 converts and inputs the driving force for the forward side and the reverse side and inputs the input driving force for the forward side and the reverse side to the pair of left and right front wheels 1, 1 and the pair of left and right rear wheels 2, 2. introduce. The transmission case 23 includes a pair of steering clutches 33 and 33 that are installed in the rear part of the transmission case 23. One steering clutch 33 of the pair of steering clutches 33 and 33 is an interlock provided between the clutch operating arm 34 and the knuckle arm 21 when the front wheel 1 is steered leftward by a set angle or more. Switching to the cut-off state is effected by the action of the rod 35, the transmission to the rear wheel 2 on the left side is cut off, and then the wheel 2 is put into the idle state. The other steering clutch 33 of the pair of steering clutches 33, 33 is provided across the clutch operating arm 34 and the knuckle arm 21 when the front wheel 1 is steered rightward and beyond a set angle. The operation is switched to the cut state by the action of the interlocking rod 35, the transmission to the right rear wheel 2 is cut off, and the rear wheel 2 is made idle.

  6 and 7 are sectional views of the torque generator 40. FIG. 5 is a hydraulic circuit diagram of the torque generator 40. 6 and 7 are sectional views of the torque generator 40. As shown in these drawings, the torque generator 40 includes the input shaft 41 and the output shaft 42, as well as a rotary valve 50 according to an embodiment of the present invention as a control valve having a valve casing 51, A swash plate type piston motor 90 having a motor casing 91 (hereinafter abbreviated as “piston motor 90”) is provided.

  As shown in FIGS. 6 and 7, the rotary valve 50 includes the valve casing 51, a cylindrical sleeve 60 rotatably accommodated in an assembly hole 52 of the valve casing 51, and a relative to the sleeve 60. A spool 70 that is rotatably fitted therein is provided.

  The valve casing 51 includes one pump port 54, one tank port 55, and a pair of operation oil passages 56 and 56. The pump port 54 is connected to the hydraulic pump P through an oil supply passage 57. The hydraulic pump P takes out the lubricating oil stored in the transmission case 23 and supplies it to the pump port 54 as hydraulic oil. The tank port 55 is connected to the mission case 23 as a tank via an oil drainage path 58. One operating oil path 56 of the pair of operating oil paths 56, 56 communicates with one of a pair of drive oil paths 92, 92 provided in the motor casing 91, and the other operating oil path 56 is connected to the pair of operating oil paths 56, 56. It communicates with the other of the drive oil passages 92, 92.

  FIG. 8 is a plan view of the sleeve 60. FIG. 9A is a cross-sectional view taken along the line IX-IX (a) of FIG. FIG. 9B is a cross-sectional view taken along the line IX-IX (b) in FIG. FIG. 9C is a cross-sectional view taken along the line IX-IX (c) in FIG. FIG. 9D is a cross-sectional view taken along the line IX-IX (d) in FIG. As shown in these drawings and FIGS. 6 and 7, the sleeve 60 has six first actuators that are arranged in the sleeve 60 in a circumferential direction in a portion of the sleeve 60 that faces the main body 71 of the spool 70. An oil passage hole 61 (hereinafter abbreviated as a first actuator oil passage 61), three input oil passage holes 62 provided in the sleeve portion side by side in the sleeve circumferential direction, and the sleeve portion in the sleeve circumferential direction. Six second oil passage holes 63 for actuators (hereinafter abbreviated as second actuator oil passages 63) that are arranged side by side and three drain oil passage holes 64 that are arranged to penetrate the sleeve portion in the circumferential direction of the sleeve. And.

  The first actuator oil passages 61, the input oil passage holes 62, the second actuator oil passages 63, and the discharge oil passage holes 64 are omitted from the hole forming process performed from the inner peripheral side of the sleeve 60. The hole 60 is formed by a hole forming process performed from the outer peripheral side of the sleeve 60, and has a hole shape opened on the inner peripheral surface of the sleeve 60 in a state where the hole diameter is constant at a portion located on the inner peripheral side of the sleeve 60.

  The six first actuator oil passages 61 communicate with the one operation oil passage 56 via an annular groove 65 provided on the outer peripheral surface of the sleeve 60 so as to communicate the six first actuator oil passages 61. . The six second actuator oil passages 63 communicate with the other operation oil passage 56 via an annular groove 66 provided on the outer peripheral surface of the sleeve 60 so as to communicate the six second actuator oil passages 63. . The three input oil passage holes 62 communicate with the pump port 54 via an annular groove 67 provided on the outer peripheral surface of the sleeve 60 so as to communicate the three input oil passage holes 62. The three drain oil passage holes 64 communicate with the tank port 55 through an annular groove 68 provided on the outer peripheral surface of the sleeve 60 so as to communicate with the three drain oil passage holes 64.

  The spool 70 includes the main body portion 71 located inside the sleeve 60, and a locking portion 72 and a support shaft portion 73 located inside the connecting end portion 43 of the output shaft 42. The support shaft portion 73 is a circular shaft.

  The spool 70 includes three control grooves 74 and three oil drain grooves 75 arranged in the circumferential direction of the spool on the outer peripheral surface of the main body 71, and the inside of the main body 71, the locking portion 72, and the support shaft 73. And a drain oil passage 77 provided along the spool rotation shaft core 76. The three control grooves 74 and the three oil drain grooves 75 are arranged in the spool circumferential direction in an arrangement in which one oil drain groove 75 is positioned between two adjacent control grooves 74.

  As shown in FIGS. 6 and 7, the sleeve 60 includes a plurality of positioning roll pins 80 arranged at one end of the sleeve 60 in the circumferential direction of the sleeve. Each positioning roll pin 80 is slidably engaged with an annular pin groove 79 provided on the outer peripheral surface of the spool 70, and allows the sleeve 60 and the spool 70 to rotate relative to each other while allowing relative rotation between the sleeve 60 and the spool 70. Is positioned so as not to move in the direction along the spool rotation axis 76.

  FIG. 10 is a view in the direction of the spool rotation axis when the rotary valve 50 is in a neutral state. The sleeve portion provided with the first actuator oil passage 61, the sleeve portion provided with the second actuator oil passage 63, and the sleeve portion provided with the input oil passage hole 62 are actually the spool rotation axis. In FIG. 10, the sleeve portion provided with the first actuator oil passage 61, the sleeve portion provided with the second actuator oil passage 63, and the input oil passage hole 62 are arranged. The first actuator oil passage 61, the second actuator oil passage 63, and the input oil passage hole 62 are described in a state where the provided sleeve portion overlaps in the spool rotation axis direction. FIG. 11 is a cross-sectional view of the rotary valve 50 in a neutral state. 12 and 13 are partial cross-sectional views of the rotary valve 50 in a neutral state.

As shown in these drawings, when the spool 70 reaches the center position (neutral position) in the rotation range, the rotary valve 50 is in a neutral state. Then, each of the three control grooves 74 corresponds to one corresponding first actuator oil passage 61 among the six first actuator oil passages 61 and one corresponding input oil among the three input oil passage holes 62. The passage hole 62 faces one second actuator oil path 63 corresponding to the six second actuator oil paths 63, and the input oil path hole 62 is connected to the first actuator oil path 61 and the second by the control groove 74. It communicates with the actuator oil passage 63.
On the other hand, each of the three oil drain grooves 75 corresponds to one corresponding first actuator oil path 61 of the six first actuator oil paths 61 and one corresponding one of the six second actuator oil paths 63. The first actuator oil passage 61 and the second actuator oil passage 63 are opposed to the second actuator oil passage 63 and one corresponding discharge oil passage hole 64 of the three discharge oil passage holes 64. The groove 75 communicates with the drain oil passage hole 64.

  Thereby, in the neutral state, the rotary valve 50 returns the pressure oil supplied from the hydraulic pump P to the pump port 54 from the tank port 55 to the transmission case 23 and stops the piston motor 90.

  That is, the pressure oil supplied to the pump port 54 is caused to flow into each input oil passage hole 62 via the annular groove 67 and then flow into each control groove 74 from each input oil passage hole 62. The pressure oil that has flowed into the control groove 74 is caused to flow into the first actuator oil path 61 and the second actuator oil path 63 that communicate with the control groove 74. The pressure oil that has flowed into the first actuator oil passage 61 flows into the first actuator oil passage 61 that communicates with the drain oil groove 75 via the annular groove 65, and the oil drain groove 75 from the first actuator oil passage 61. To flow into. The pressure oil that has flowed into the second actuator oil passage 63 is caused to flow into the second actuator oil passage 63 that communicates with the drain oil groove 75 via the annular groove 66, and the oil drain groove 75 from the second actuator oil passage 63. To flow into. The pressure oil that has flowed into the drain oil groove 75 flows out from the end of the drain oil groove 75 to the tank port 55 via the drain oil passage holes 64 and the annular groove 68.

  FIG. 14 is a view in the direction of the spool rotation axis when the rotary valve 50 is driven to rotate clockwise. In FIG. 14, the sleeve portion including the first actuator oil passage 61, the sleeve portion including the second actuator oil passage 63, and the sleeve portion including the input oil passage hole 62 are in the spool rotation axis direction. The first actuator oil passage 61, the second actuator oil passage 63, and the input oil passage hole 62 are described in a state where they overlap each other. FIG. 15 is a cross-sectional view of the rotary valve 50 in the right rotation driving state. FIGS. 16 and 17 are partial cross-sectional views of the rotary valve 50 in the clockwise rotation state.

As shown in these drawings, when the spool 70 is positioned at one stroke end in the rotation range, the rotary valve 50 is in the right rotation driving state. Then, each of the three control grooves 74 corresponds to one corresponding second actuator oil path 63 among the six second actuator oil paths 63 and one corresponding input oil among the three input oil path holes 62. The input oil passage hole 62 communicates with the second actuator oil passage 63 through the control groove 74 so as to face the passage hole 62. The second actuator oil passage 63 that does not communicate with the control groove 74 among the six second actuator oil passages 63 is closed by the peripheral surface of the main body 71 of the spool 70.
On the other hand, each of the three oil drain grooves 75 corresponds to one corresponding first actuator oil path 61 among the six first actuator oil paths 61 and one corresponding discharge among the three drain oil path holes 64. Opposing to the oil passage hole 64, the first actuator oil passage 61 is communicated with the drain oil passage hole 64 by the oil drain groove 75. Of the six first actuator oil passages 61, the first actuator oil passage 61 that does not communicate with the oil drain groove 75 is closed by the peripheral surface of the main body 71 of the spool 70.

  Thereby, the rotary valve 50 supplies the pressure oil supplied from the hydraulic pump P to the pump port 54 to the one drive oil path 92 of the piston motor 90 from the one operation oil path 56 in the clockwise rotation drive state. The pressure oil discharged from the other drive oil passage 92 of the piston motor 90 is returned from the tank port 55 to the transmission case 23, and the piston motor 90 is driven to rotate clockwise.

That is, the pressure oil supplied to the pump port 54 is caused to flow into each input oil passage hole 62 via the annular groove 67 and then flow into each control groove 74 from each input oil passage hole 62. The pressure oil that has flowed into the control groove 74 is caused to flow into one operation oil path 56 through the second actuator oil path 63 and the annular groove 66 that communicate with the control groove 74, and from this operation oil path 56 to one drive oil. Supply to path 92.
On the other hand, the pressure oil discharged from the other drive oil passage 92 is caused to flow into the annular groove 65 through the other operation oil passage 56, and the oil discharge groove 75 from the annular groove 65 through the second actuator oil passage 63. To flow into. The pressure oil that has flowed into the drain oil groove 75 flows out from the end of the drain oil groove 75 to the tank port 55 through the drain oil passage hole 64 and the annular groove 68.

  FIG. 18 is a view in the direction of the spool rotation axis when the rotary valve 50 is driven to rotate counterclockwise. In FIG. 18, the sleeve portion provided with the first actuator oil passage 61, the sleeve portion provided with the second actuator oil passage 63, and the sleeve portion provided with the input oil passage hole 62 are in the spool rotation axis direction. The first actuator oil passage 61, the second actuator oil passage 63, and the input oil passage hole 62 are described in a state where they overlap each other. FIG. 19 is a cross-sectional view of the rotary valve 50 in a left-rotation driving state. 20 and 21 are partial cross-sectional views of the rotary valve 50 in the left rotation driving state.

As shown in these drawings, when the spool 70 is positioned at the other stroke end in the rotation range, the rotary valve 50 is in the left rotation driving state. Then, each of the three control grooves 74 corresponds to one corresponding input oil passage hole 62 among the three input oil passage holes 62 and one corresponding first actuator among the six first actuator oil passages 61. The input oil passage hole 62 communicates with the first actuator oil passage 61 through the control groove 74 so as to face the oil passage 61. Of the six first actuator oil passages 61, the first actuator oil passage 61 that does not communicate with the control groove 74 is closed by the peripheral surface of the main body 71 of the spool 70.
On the other hand, each of the three oil drain grooves 75 corresponds to one corresponding second actuator oil path 63 among the six second actuator oil paths 63 and one corresponding discharge among the three drain oil path holes 64. Opposing to the oil passage hole 64, the second actuator oil passage 63 is communicated with the drain oil passage hole 64 by the oil drain groove 75. Of the six second actuator oil passages 63, the second actuator oil passage 63 that does not communicate with the oil drain groove 75 is closed by the peripheral surface of the main body 71 of the spool 70.

  Thereby, in the left rotation drive state, the rotary valve 50 supplies the pressure oil supplied from the hydraulic pump P to the pump port 54 from the other operation oil path 56 to the other drive oil path 92 of the piston motor 90, Pressure oil discharged from one drive oil passage 92 of the piston motor 90 is returned to the transmission case 23 from the tank port 55, and the piston motor 90 is driven to rotate counterclockwise.

That is, the pressure oil supplied to the pump port 54 is caused to flow into each input oil passage hole 62 via the annular groove 67 and then flow into each control groove 74 from each input oil passage hole 62. The pressure oil that has flowed into the control groove 74 is caused to flow into the other operation oil path 56 via the first actuator oil path 61 and the annular groove 65 that communicate with the control groove 74, and the other drive oil from this operation oil path 56. Supply to path 92.
On the other hand, the pressure oil discharged from one drive oil passage 92 is caused to flow into the annular groove 66 through one operation oil passage 56, and the oil discharge groove 75 from the annular groove 66 through the second actuator oil passage 63. To flow into. The pressure oil that has flowed into the drain oil groove 75 flows out from the end of the drain oil groove 75 to the tank port 55 through the drain oil passage hole 64 and the annular groove 68.

  As shown in FIGS. 6 and 7, the sleeve 60 is connected to the output shaft 42 by a connection roll pin 81 attached over an end opposite to the side where the positioning roll pin 80 is located and a connection end 43 of the output shaft 42. It is connected to the unit so as to rotate freely.

  The spool 70 is integrally connected to the input shaft 41 by being integrally formed with the input shaft 41. The spool 70 is engaged with the output shaft 42 by engaging means 85 having the locking portion 72.

  FIG. 22 is a cross-sectional view of the engaging means 85. As shown in this figure, the engaging means 85 is connected to the engaging portion 72, the bent leaf spring 86 provided on both sides of the engaging portion 72, and the connecting end portion 43 of the output shaft 42. A pair of support portions 44, 44 provided in a bifurcated shape is provided.

  The locking portion 72 is inserted between the pair of support portions 44 and 44. Each of the bending spring plates 86 is interposed between the locking portion 72 and the one support portion 44. Each of the bent plate springs 86 includes an anti-slip curved portion 86a that has entered the recessed portion 44a of the support portion 44, and the support shaft portion 44 and the locking portion 72 at both ends of the flex plate spring 86 relative to the anti-detent curved portion 86a. And an urging curved portion 86b sandwiched between the two.

  The detachment-preventing curved portion 86a prevents the bent leaf spring 86 from being detached by engaging with the support portion 44 by entering the recessed portion 44a. When the locking portion 72 rotates, each of the urging curved portions 86b is pressed by the locking portion 72 and elastically deformed to the extension side, and the support portion 44 is engaged via the end of the bent leaf spring plate 86. The rotation of the spool 70 with respect to the sleeve 60 until the stop portion 72 is stopped is allowed.

  FIG. 22A is a transverse cross section of the engaging means 85 in a neutral state of the rotary valve. As shown in this figure, the engaging means 85 is configured so that, in the neutral state of the rotary valve 50, the engaging portion 72 is moved to the center position (in the rotational range) by the pressing operation by the biasing curved portion 86b of the pair of bending spring plates 86, 86. The spool 70 is positioned at the neutral position.

  FIG. 22B is a transverse cross-sectional view of the engagement means 85 in a state where the rotary valve rotates clockwise. As shown in this figure, when the engaging portion 72 rotates to one stroke end in the rotation range determined by the distance between the pair of support portions 44, 44, the engagement means 85 is one of the pair of bending spring plates 86, 86. When the biasing curved portion 86b is elastically deformed by the pressing of the locking portion 72, the pair of support portions 44, 44 stop the locking portion 72 via the ends of the bending spring plate 86, and the spool 70 Is positioned at one stroke end, and the rotational force of the spool 70 as the rotational force of the input shaft 41 rotated by the steering handle 20 is transmitted to the output shaft 42.

  FIG. 22C is a transverse cross-sectional view of the engaging means 85 in the rotary valve counterclockwise driving state. As shown in this figure, the engaging means 85 is configured such that when the locking portion 72 rotates to the other stroke end of the rotation range, the other biasing curved portion 86b of the pair of bending spring plates 86, 86 causes the locking portion 72 to move. By being elastically deformed by pressing, the pair of support portions 44, 44 stop the locking portion 72 via the end of the bending spring plate 86, position the spool 70 at the other stroke end, and the steering handle. The rotational force of the spool 70 as the rotational force of the input shaft 41 that is rotated by the motor 20 is transmitted to the output shaft 42.

  As shown in FIGS. 6 and 7, the piston motor 90 includes the motor casing 91, a cylinder block 93 and a swash plate 94 provided inside the motor casing 91, and an output shaft 42 described in the cylinder block 93. And a plunger 95 slidably provided in a state of being distributed around the periphery.

  The motor casing 91 includes a casing main body 91 a fixed to the transmission case 23 and an oil passage plate 91 b provided with the pair of driving oil passages 92, 92. The oil passage plate 91b is connected to the casing body 91a by a connecting bolt 96 to close the opening of the casing body 91a. The oil passage plate 91 b and the valve casing 51 are connected by the connecting bolt 96. Thereby, the motor casing 91 and the valve casing 51 are connected to each other.

  The cylinder block 93 is connected to the output shaft 42 so as to be integrally rotatable by spline engagement. The swash plate 94 is supported via a bearing 98 by a support block 97 fixed to the casing body 91a. The support block 97 is detachably supported by the casing body 91a, and the rotation speed of the piston motor 90 is changed by replacing the swash plate 94 with one having a different inclination angle of the inclined cam surface. It is possible.

  That is, the piston motor 90 pushes the plunger 95 out of the cylinder block 93 by the pressure oil supplied by one of the pair of drive oil passages 92 and 92, and the end of the plunger 95 is slidably contacted with the inclined cam surface of the swash plate 94. Thus, the axial plunger motor is configured to rotationally drive the cylinder block 93 and thereby rotationally drive the output shaft 42.

  That is, in the torque generator 40, when the steering handle 20 is rotated in the clockwise direction, the input shaft 41 is rotated and the spool 70 is rotated. By positioning at the stroke end, the rotary valve 50 is switched to the right rotation driving state, and the rotary valve 50 supplies and discharges the pressure oil to and from the piston motor 90 to drive the piston motor 90, and the piston motor 90 outputs it. The shaft 42 is driven in a rotation direction corresponding to the rotation direction of the steering handle 20, and a steering operation force in an operation direction corresponding to the rotation direction of the steering handle 20 is output from the output shaft 42. To the right.

  When the steering handle 20 is rotated in the counterclockwise direction, the torque generator 40 rotates the input shaft 41 to rotate the spool 70, and accordingly, the engaging means 85 causes the spool 70 to move to the other stroke end. , The rotary valve 50 is switched to the left rotation driving state, and the rotary valve 50 supplies and discharges the pressure oil to and from the piston motor 90 to drive the piston motor 90, and the piston motor 90 outputs the output shaft 42. Is driven in the rotation direction corresponding to the rotation direction of the steering handle 20, and the steering operation force in the operation direction corresponding to the rotation direction of the steering handle 20 is output from the output shaft 42, and the left and right front wheels 1, 1 are turned leftward. Steer to the side.

  When the rotation operation of the steering handle 20 is stopped, the torque generator 40 stops the input shaft 41 and stops the spool 70, and the rotation operation amount of the output shaft 42 by the piston motor 90 becomes the rotation operation amount of the steering handle 20. When the corresponding rotational operation amount is reached, the sleeve 60 rotates with respect to the spool 70, whereby the rotary valve 50 is switched to the neutral state. The rotary valve 50 stops the supply of pressure oil to the piston motor 90, and the piston motor 90 Is stopped, the driving of the output shaft 42 by the piston motor 90 is stopped, the output of the steering operation force by the output shaft 42 is stopped, and the left and right front wheels 1, 1 are steered corresponding to the operation position of the steering handle 20. Steering posture oriented in the direction with a swing angle corresponding to the rotational operation angle of the steering handle 20 To hold.

  As shown in FIG. 6, the torque generator 40 is incorporated in the casing main body 91a, an induction oil passage 101 provided by inserting a bearing 100 across the valve casing 51 and the hydraulic plate 91b of the pomotor casing 91. The relief valve 102 is provided.

  A rotary valve side of the guide oil passage 101 communicates with the assembly hole 52 of the valve casing 51 and communicates with the drain oil passage 77 through an oil passage 103 using a hollow portion of the connection roll pin 81. . The piston oil side of the induction oil passage 101 is connected to an oil passage that uses a gap generated between the cylinder block 93 and the output shaft 42 at a portion of a spline structure that engages the cylinder block 93 and the output shaft 42. And communicates with the internal space of the motor casing 91.

  In other words, the guide oil passage 101 is generated in the valve casing 51 and directly flows into the guide oil passage 101, and the drain oil passage 77 through the oil passage 104 using the hollow portion of the positioning roll pin 80. The leaked oil that has flowed into the motor casing 91 flows into the motor casing 91 and is supplied to the piston pump 90 as oil for immersing the motor body having the plunger 95 and the cylinder block 93.

[Another Example]
The present invention can be applied to a rotary valve configured to control a hydraulic cylinder instead of the above-described embodiment. Therefore, the piston motor 90, the hydraulic cylinder, and the like are collectively referred to as a hydraulic actuator 90, and the motor casing 91 is referred to as an actuator casing 91.

Overall side view of riding rice transplanter Side view of the power steering device installation part of the self-propelled vehicle Top view of power steering device Diagram of interlocking mechanism Hydraulic circuit diagram of torque generator Cross section of torque generator Cross section of torque generator Top view of sleeve (A) is a cross-sectional view taken along the line IX-IX (a) in FIG. 8, (b) is a cross-sectional view taken along the line IX-IX (b) in FIG. 8, and (c) is a cross-sectional view taken along the line IX-IX in FIG. c) Cross-sectional arrow view, (d) is IX-IX (d) cross-sectional arrow view of FIG. Spool rotation axis direction view in the neutral state of the rotary valve Cross section in the neutral state of the rotary valve Partial sectional view of the rotary valve in the neutral state Partial sectional view of the rotary valve in the neutral state View of spool rotation direction when the rotary valve is driven clockwise Cross-sectional view of the rotary valve in the right rotation drive state Partial sectional view of the rotary valve in the clockwise rotation state Partial sectional view of the rotary valve in the clockwise rotation state View of spool rotation direction when the rotary valve is driven counterclockwise Cross section of the rotary valve in the left rotation drive state Partial sectional view of the rotary valve in the left rotation drive state Partial sectional view of the rotary valve in the left rotation drive state (A) is a cross-sectional view of the engaging means in the neutral position of the rotary valve, (b) is a cross-sectional view of the engaging means in the rotary valve clockwise rotation state, and (c) is a rotary view of the engaging means. Cross-sectional view in the valve counterclockwise drive state

Explanation of symbols

51 Valve casing 60 Sleeve 70 Spool 90 Hydraulic actuator 91 Actuator casing 101 Guide oil passage

Claims (2)

A rotary valve configured to control a hydraulic actuator by a sleeve and a spool that is rotatably fitted in the sleeve;
The oil passage hole for the actuator, which is provided in the sleeve so as to be connected to the hydraulic actuator so as to supply and discharge the pressure oil to and from the hydraulic actuator, has a constant hole diameter at a portion located on the inner peripheral side of the sleeve. A rotary valve that is opened in an inner peripheral surface of the sleeve in a state. A valve casing for housing the sleeve is connected to the actuator casing of the hydraulic actuator;
The rotary valve according to claim 1, wherein an induction oil passage through which leak oil generated in the valve casing flows into the hydraulic actuator is provided across the valve casing and the actuator casing.

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