JP3583063B2 - Agricultural work equipment steering device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
According to the present invention, a pair of side clutches respectively acting on a pair of left and right traveling devices are individually operably provided by a pair of clutch hydraulic actuators, and one of the traveling devices with the side clutch disengaged is decelerated or driven. A first turning means for changing the traveling direction of the fuselage by turning the traveling device to the inside of the vehicle so as to be freely turned on and off by a first hydraulic actuator for turning is provided, and one of the traveling devices with the side clutch disengaged is braked or reversed. The second turning means, which drives the traveling device to turn inside the turning direction and changes the traveling direction of the aircraft with a smaller turning radius than when turning by the first turning means, is provided by a second turning hydraulic actuator. The present invention relates to a steering device for an agricultural work machine, which is provided so as to be freely turned on and off.
[0002]
[Prior art]
The agricultural working machine can steer the aircraft in a turning mode having different turning radii by operating the side clutch, the first turning means, and the second turning means.
In this kind of agricultural work machine, when the turning mode selection valve is switched by a turning mode selecting operation tool and the steering switching valve and the turning control valve are operated by the steering operation tool, the turning radius is different. In order to steer the aircraft in such a manner, it is necessary to operate both the operating tool for selecting the turning mode and the steering operating tool.
For this reason, conventionally, as disclosed in Japanese Patent Application Laid-Open No. 7-47973, for example, a swing mode selection valve is configured to be operated to be switched by an electromagnetic solenoid, and based on the result of detection of the operation position of the steering operation tool. A control device for switching the turning mode selection valve is provided, and a linkage mechanism for linking the steering operation tool to the steering switching valve and the turning control valve is provided, and one steering operation tool is operated left or right from the neutral position. As the vehicle travels, the side clutch of one of the traveling devices is disengaged, the first turning means is engaged, and the second turning means is disengaged. A second turning state in which the side clutch of the device is disengaged, the first turning means is disengaged, and the second turning means is engaged sequentially appears, and one steering operation tool is provided. Varied only by turning mode operation was followed by a body capable steering operation.
[0003]
[Problems to be solved by the invention]
In the conventional steering apparatus described above, the steering switching valve and the turning control valve are switched by a manual operation force applied to the steering operation tool, and a linking operation for linking the steering operation tool to each valve. In some cases, the operation became heavy due to a mechanism or operation resistance generated by the control valve. Further, in the agricultural working machine, since the mission oil is often used as the hydraulic oil, dust may enter into each valve. Then, the valve may not be easily switched by the operation force of the electromagnetic solenoid.
SUMMARY OF THE INVENTION An object of the present invention is to provide a steering device of an agricultural work machine which can be operated not only in a different turning mode but also in a light operation and easily avoiding a poor switching by dust simply by operating a steering operation tool. Is to do.
[0004]
[Means for Solving the Problems]
The configuration, operation and effect of the invention according to claim 1 are as follows.
[0005]
〔Constitution〕
A pair of side clutches acting separately on a pair of left and right traveling devices are respectively operated by a pair of clutch hydraulic actuators. Individually A first turning means, which is operably equipped and changes the traveling direction of the body by turning or decelerating one of the traveling devices with the side clutch disengaged so that the traveling device is turned inside, is provided by a first hydraulic pressure for turning. An on / off operation is freely provided by an actuator, and the traveling device whose one side clutch is disengaged is braked or reversely driven to turn the traveling device inside the turning direction, and the turning is smaller than when turning by the first turning means. In a steering device for an agricultural work machine provided with a second turning means for changing the running direction of the body by a radius by a second hydraulic actuator for turning so as to be freely turned on and off, an operation direction from a neutral position of one steering operation tool is provided. And a steering switch valve for operating the pair of clutch hydraulic actuators, and a sensor for detecting an operation stroke. And a steering mode switching valve for selectively operating a swing mode selection valve for selectively connecting the first swing hydraulic actuator and the second swing hydraulic actuator to a hydraulic supply source. One A steering control device that includes an electric motor and automatically operates the electric motor based on information from the sensor, and a steering operation tool is linked to a turning control valve that controls hydraulic pressure supply to the turning mode selection valve. And a steering control mechanism having a mechanical interlocking mechanism for causing the pair of side clutches to be engaged when the steering operation tool is operated to the neutral position, and the first turning means and A straight running state in which the second turning means is turned off appears, and when the steering operation tool is operated left or right from the neutral position, The turning control valve is operated via the mechanical interlocking mechanism to supply hydraulic pressure to the turning mode selection valve, and the sensor detects the operation direction and operation stroke from the neutral position of the steering operation tool. Actuating the one electric motor based on the operation of a member interlocked with forward / reverse rotation of the electric motor, the steering switching valve is switched to a left-turn or right-turn steering side, and The turning mode selection valve is controlled to switch in the same direction regardless of whether the electric motor is rotating forward or reverse. First, a first turning state in which the side clutch of one traveling device is disengaged, the first turning means is engaged, and the second turning means is disengaged, and the steering operation is further performed. When the tool is operated to one side, the side clutch of one traveling device is disengaged, the first turning means is disengaged, and the second turning state in which the second turning means is engaged is set. The steering control mechanism is configured to appear.
[0006]
[Action]
When the steering operation tool is operated from the neutral position, the steering control means One of the electric motors is operated, and the steering switching valve is operated to switch to a left-turn or right-turn steering side based on an operation of a member linked to forward and reverse rotation of the electric motor, and the electric motor is operated. The swing mode selection valve is controlled to switch in the same direction regardless of whether the The turning control valve is switched for the interlocking mechanism, so that the first turning state appears first, the traveling direction changes, and then the second turning state appears, and the turning control valve switches to the first turning state. The running direction also changes with a small turning radius.
[0007]
Since the steering switching valve and the turning mode selection valve are switched by the electric motor, the operating force required to operate the steering operation tool can be reduced as compared with the switching operation performed by the manual operation force. Further, even if the switching operation is performed with a stronger operating force than the electromagnetic solenoid and the switching is performed due to the inflow of dust, the switching operation is easily performed by overcoming the resistance.
[0008]
〔effect〕
Therefore, by operating only one steering operation tool and operating it lightly, the first turning state can be easily made to appear to steer the aircraft, and the second turning state can be made to appear. The aircraft can be steered with a turning radius smaller than the turning radius in one turning state. In addition, even if dust enters the steering switching valve or the turning mode selection valve and the switching resistance is slightly increased, the switching operation is firmly performed and the switching failure is less likely to occur.
[0009]
The configuration, operation and effect of the invention according to claim 2 are as follows.
[0010]
〔Constitution〕
In the configuration of the invention according to claim 1, a rotating cam that is rotated forward and backward by the electric motor, and a swinging operation that is swingably operated by an operation cam portion provided on a peripheral surface of the rotating cam to switch the steering switching valve. And a dynamic link.
[0011]
[Action]
When the rotating cam is rotated in the forward direction from the neutral position, the swinging link is operated to swing to one side by the contact between the operating cam portion on the peripheral surface thereof and the swinging link, and the steering switching valve is moved from the neutral position. When the rotating cam is switched to one of the left steering side and the right steering side and the rotating cam is rotated in the reverse rotation direction from the neutral position, the swinging link is contacted by the operating cam portion on the peripheral surface thereof and the swinging link. Can be operated to swing the steering switch valve from the neutral position to the other of the left steering side and the right steering side. When the rotating cam rotates and the turning mode selection valve is operated even after the steering switching valve is switched from the neutral position to the left steering side or the right steering side, the swing link of the operating cam portion is used at this time. If the abutting part has an arc shape centered on the rotation axis of the rotating cam, operate the turning mode selection valve while maintaining the steering switching valve on the left steering side or right steering side. it can.
[0012]
〔effect〕
A shape in which the portion acting on the swing link for operating the steering switching valve to the left steering side and the portion acting on the swing link for operating the steering switching valve to the right steering side are the same. By simply adopting a simple rotating cam, the steering switching valve can be switched between left steering and right steering, and the steering switching valve after switching to the left steering or right steering. Can be maintained in the operation state, and the operation structure can be simplified.
[0013]
The configuration, operation and effect of the invention according to claim 3 are as follows.
[0014]
〔Constitution〕
In the configuration of the invention according to claim 1 or 2, the rotating cam that is rotated by the electric motor, and a free end side abuts on the rotating cam, and is swingably operated by the rotating cam in a state of being swingably operated by the rotating cam. The swinging link includes a supported swinging link, and an interlocking rod that links the free end side of the swinging link to the operating section of the turning mode selection valve.
[0015]
[Action]
By appropriately setting the arrangement of the point of force with which the rotating cam of the swing link abuts, the point of action of the interlocking rod, and the fulcrum rotatably supported by the fixed part, the output of the electric motor is relatively small and small. Even if the above-mentioned motor is adopted, the driving force of the motor is strongly applied to the operation section of the turning mode selection valve, so that the switching operation of the turning mode selection valve can be reliably performed.
[0016]
〔effect〕
A highly reliable one in which the switching of the swing mode selection valve is reliably performed can be obtained compactly by employing a relatively small motor.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a right side view of a combine, which is an example of an agricultural working machine to which the present invention is applied. This combine combines a cutting pre-processing unit 3 with a front part of a traveling machine body 2 having a pair of right and left crawler-type traveling devices 1L and 1R so as to be able to move up and down, and a threshing device 4 and a grain tank on the machine body. 5, engine 6, control unit 7, etc.
[0018]
Hereinafter, the transmission structure of the traveling devices 1L and 1R will be described with reference to FIGS. The description in the left-right direction in the description is based on the left-right direction of the aircraft, and has a relationship opposite to the left-right direction in these figures as viewed from the front.
[0019]
The power of the engine 6 is transmitted to a hydrostatic continuously variable transmission (HST) 8 as a main transmission capable of switching between forward and reverse, and the transmission output thereof is transmitted to a transmission case 9. The power input to the transmission case 9 is transmitted to the first shaft 10 via gears G1 and G2, and then transmitted to the auxiliary transmission mechanism 11 via gears G3 and G4. Further, of the power taken out of the case from the first shaft 10, only the forward rotation power is transmitted to the pre-cutting unit 3 via the one-way clutch OC. The hydrostatic stepless transmission 8 is operated by a main transmission lever 29 provided in the control unit 7.
[0020]
The sub-transmission mechanism 11 performs three-stage gear shifting in a constant mesh manner. The sub-transmission mechanism 11 includes a small-diameter gear G5, a medium-diameter gear G6, and a large-diameter gear G7, which are loosely mounted on the second shaft 12, and the third shaft 13 The gears G8, G9, and G10 fixed on the second shaft 12 are always engaged with each other, and the two shift sleeves S1 and S2 provided on the second shaft 12 are shifted so that one of the three normally meshed gear pairs is shifted. The transmission is configured to perform a speed change transmission from the second shaft 12 to the third shaft 13.
[0021]
That is, as shown in FIGS. 6 and 7, the shift sleeves S1 and S2 are provided with a pair of shift forks 15a and 15b provided on a shifter 15 that slides along a support shaft 14 horizontally supported in a transmission case. The shift sleeves S1 and S2 are simultaneously shifted in the same direction as the shifter 15 slides. An operation arm 16a that engages with the shifter 15 is provided at the tip of a shift operation shaft 16 that is mounted in the transmission case 9 in a front and rear direction. The shifter 15 is configured to slide left and right by rotating the speed change operation shaft 16.
[0022]
Here, the shift sleeve S1 is directly spline-engaged with the second shaft 12 throughout the shift range, whereas the shift sleeve S2 is fitted with the boss portion of the gear G6 and the spline externally fitted on the second shaft 12. The shift can be performed over the spline collar 17 and the boss portion of the gear G7, and the three-speed shift is performed as follows.
[0023]
When the shifter 15 is at the low speed "L" position, as shown in FIG. 8, the shift sleeve S1 engages the boss of the gear G5 over the second shaft 12, and the shift sleeve S2 engages the boss of the gear G6. , And the power of the second shaft 12 is transmitted to the third shaft 13 at low speed via the shift sleeve S1 and the gears G5 and G8. When the shifter 15 is at the middle speed "M" position, as shown in FIG. 9, the shift sleeve S1 is supported only on the second shaft 12, and the shift sleeve S2 is connected to the boss portion of the gear G6 and the spline collar. 17, the power of the second shaft 12 is transmitted to the third shaft 13 at an intermediate speed via the spline collar 17, the shift sleeve S2, and the gears G6, G9. When the shifter 15 is in the neutral "N" position, as shown in FIG. 10, the shift sleeve S1 is supported only by the second shaft 12, and the shift sleeve S2 is supported by the spline collar 17 only. And the power transmission from the second shaft 12 to the third shaft 13 is shut off. When the shifter 15 is at the high speed "H" position, as shown in FIG. 11, the shift sleeve S1 is supported only by the second shaft 12, and the shift sleeve S2 is connected to the boss of the gear G7 and the spline collar 17 as shown in FIG. And the power of the second shaft 12 is transmitted at high speed to the third shaft 13 via the spline collar 17, the shift sleeve S2, the gears G7 and G10.
[0024]
As shown in FIG. 7, the shifter 15 uses a ball detent 18 to lower the low speed “L”, which is the harvesting speed of the lodging grain, the medium speed “M”, which is the standard harvesting speed, and the neutral “N”. , And at a high speed “H” which is a moving speed.
[0025]
The power transmitted to the third shaft 13 as described above is transmitted to the center gear G11 of the fourth shaft 19 via the central gear G9, and then to the left and right side clutches 20L, 20R, the axle gear 21L, The power is transmitted to the left and right traveling devices 1L and 1R via the 21R and the axles 22L and 22R.
[0026]
As shown in FIGS. 4 and 5, the side clutches 20L and 20R are loosely fitted to the fourth shaft 19 and shift the side clutch gears 23L and 23R constantly engaged with the axle gears 21L and 21R to shift the side clutch gears. The power transmission from the center gear G11 to the axles 22L, 22R is interrupted by engaging and disengaging the center internal teeth of the center gear G11 from the side, and the side clutch gears 23L, 23R are shifted. The means are configured as follows.
[0027]
As shown in FIGS. 4 and 5, the fourth shaft 19 is configured as a stepped shaft having a large diameter at the central portion, and the side clutch gears 23 </ b> L and 23 </ b> R are connected to the large diameter portion of the fourth shaft 19. It has a stepped inner diameter that fits over the small diameter portion, and oil chambers g and h are provided between the step portions. Normally, the springs 24L and 24R slidably urge the center gear G11 side to be held at the clutch engagement position, and the oil chambers g and g are provided through oil passages a and b formed inside the fourth shaft 19. When the pressure oil is supplied to h and each of the side clutch gears 23L, 23R is shifted to the limit against the springs 24L, 24R, the clutch is disengaged from the center gear G11 and a clutch disengaged state is brought about. When the side clutch gears 23L, 23R are shifted to the clutch disengaged position, the oil passages a, b for supplying pressure oil are connected to an oil passage d formed inside the fourth shaft 19. It has become.
[0028]
As a result, the left side clutch 20L has a hydraulic piston type hydraulic actuator 23a on the inner peripheral side of the side clutch gear 23L, and is turned on and off by the hydraulic actuator 23a. The right side clutch 20R is a hydraulic piston type hydraulic actuator 23b on the inner peripheral side of the side clutch gear 23R, and is turned on and off by the hydraulic actuator 23b.
[0029]
After reaching the clutch disengagement position where the side clutch gears 23L and 23R are disengaged from the center gear G11, the side clutch gears 23L and 23R are attached to the steering side gears 25L and 25R loosely fitted to both end portions of the fourth shaft 19, respectively. It is connectable via multiple disc type turning clutches 90L and 90R.
[0030]
As shown in FIG. 5, the turning clutches 90L, 90R have pistons 92L, 92R fitted inside large-diameter clutch cases 91L, 91R connected to the side clutch gears 23L, 23R so as to be integrally rotatable. The friction plates 94L and 94R are laminated and interposed between the spline bosses 93L and 93R extending from the steering side gears 25L and 25R and the clutch cases 91L and 91R. The pistons 92L and 92R are urged toward the clutch disengagement side by the springs 95L and 95R, and pressurized oil is supplied to the oil chambers i and j in the clutch cases 91L and 91R so that the pistons 92L and 92R resist the springs 95L and 95R. By displacing and pressing the friction plates 94L, 94R, the side clutch gears 23L, 23L, It is configured to perform power transmission to 3R.
[0031]
Here, the oil chambers i and j for operating the pistons 92L and 92R of the turning clutches 90L and 90R are connected to the oil chambers g and h for operating the side clutch gears 23L and 23R by a communication oil passage k formed in the gears. , M, and the communication oil passages k, m are provided with throttle passage portions p, q.
[0032]
Further, springs 100L, 100R for pressing the pistons 92L, 92R toward the clutch engagement side are incorporated at a plurality of positions in the circumferential direction inside the turning clutches 90L, 90R, so that the pistons 92L, 92R are appropriately lightly frictionally transmitted. , And the low torque rotational power is always transmitted from the steering side gears 25L, 25R to the clutch cases 91L, 91R.
[0033]
The steering side gears 25L, 25R are engaged with the gears 27L, 27R fixed to both ends of the fifth shaft 26, and the gear G13 loosely fitted to the fifth shaft 26 is connected to the center gear G11. The gear G12 is engaged with a small-diameter gear G12 connected to the side and is interlocked with the gear G12.
[0034]
As shown in FIG. 4 and the like, a multi-plate clutch C is provided between the gear G13 and the fifth shaft 26 as first turning means for performing gentle turning. In the clutch C, a hydraulic piston 32 as an example of a turning first hydraulic actuator is normally retracted and returned by a spring 31 incorporated therein, and is maintained in a clutch disengaged state, and an oil passage formed inside the fifth shaft 26 is provided. The supply of the pressure oil via c causes the hydraulic piston 32 to be displaced against the spring 31 and switch to the clutch engaged state.
[0035]
As shown in FIG. 4 and the like, one end of a fifth shaft 26 is supported by a side cover 33 attached to the right side surface of the transmission case 9, and the side cover 33 turns with the clutch C engaged. A multi-plate type braking mechanism B is provided as a second turning means for controlling a pivot turn in which the turning radius is smaller than the turning radius. In the braking mechanism B, a ring-shaped hydraulic piston 34 as an example of a second hydraulic actuator for turning is advanced into the case by application of oil pressure, and presses and displaces the pressing plate 35 against the interior spring 36. Then, a friction braking action is added to the fifth shaft 26, the application of the hydraulic pressure is released, and the pressing plate 35 is returned and retracted by the internal spring 36, whereby the braking is released. Is incorporated in a hydraulic block 37 attached to the outer surface of the side cover 33.
[0036]
FIG. 12 shows a hydraulic circuit diagram and a control system diagram for steering for operating the side clutches 20L and 20R, the turning clutches 90L and 90R, the clutch C, and the braking mechanism B. In the figure, V1 is a steering switching valve for selectively shifting the hydraulic actuator 23a of the left side clutch 20L and the hydraulic actuator 23b of the right side clutch 20R, and is provided outside the transmission case 9. The neutral position and the forward / reverse position are selected by the steering electric motor 110. V2 is a swing mode selection valve for switching the swing mode by selectively connecting the hydraulic piston 32 of the clutch C and the hydraulic piston 34 of the braking mechanism B to an oil passage e as a hydraulic supply source. It is urged to a position where hydraulic oil is supplied to the hydraulic piston 32 of the clutch C, and is switched to a position where hydraulic oil is supplied to the hydraulic piston 34 of the braking mechanism B by the electric motor 110 provided outside the transmission case 9. I have.
[0037]
V3 in FIG. 12 is a sequence valve connected to an oil passage d formed inside the fourth shaft 19, and its operating pressure is controlled by the side clutch gears 23L and 23R of the side clutches 20L and 20R. The pressure is shifted to the clutch disengagement position and set to a pressure for balancing with the springs 24L and 24R. A variable relief valve V4 as a swing control valve is connected to the lower side of the sequence valve V3, communicates with a transmission case 9 also serving as a hydraulic oil tank, and is connected between the sequence valve V3 and the variable relief valve V4. Is connected to the primary side of the turning mode selection valve V2, and the pressure of the variable relief valve V4 is adjusted so that the turning mode selection valve V2 is refueled or stopped. Or
[0038]
The steering switching valve V1 and the turning mode selection valve V2 are configured to be switched by the electric motor 110 based on the operation structure shown in FIGS.
[0039]
That is, the steering switching valve V1 is incorporated in the hydraulic block 37, and can be switched by swinging the swing link 64 located outside the hydraulic block 37 around the axis of the support shaft 62. The swing link 64 is configured to be urged to return to the neutral position by a return spring 112 configured so that both ends thereof abut a spring receiving pin 64a provided at the base of the swing link 64.
[0040]
A rotary cam 114 is attached to the output shaft of the electric motor 110 supported by a motor attachment body 113 fixed to the transmission case 9 so as to be rotatable integrally. When the rotary cam 114 is at the neutral position, a neutral portion 115a, which is a concave portion of the operation cam portion 115 provided on the peripheral surface of the rotary cam 114, is provided by attaching a roller to the free end of the swing link 64. The swing link 64 is operated to the neutral position corresponding to the operating portion 64b. Then, the swing link 64 operates the steering switching valve V1 to the neutral state. When the electric motor 110 is driven in the forward rotation direction or the reverse rotation direction from this state, the rotating cam 114 is operated in the forward rotation direction or the reverse rotation direction by the driving force of the electric motor 110, and the operation cam portion of the rotation cam 114 is operated. A steering portion 115b, which is an arc portion located on the lateral side of the neutral portion 115a of 115, abuts the operating portion 64b of the swing link 64 to move the swing link 64 from the neutral position to the left steering side or right steering. Swing to the side. Then, the swing link 64 switches the steering switching valve V1 to the left or right turning steering side. Steering switching valve V1 is switched to the steering side of left turn or right turn. Changed Even if the rotating cam 114 is further rotated later, since the steering portion 115b of the operation cam portion 115 has an arc shape centered on the rotation axis of the rotating cam 114, the swing link 64 moves to the steering side. The steering switching valve V1 is maintained on the steering side of the left turn or the right turn.
[0041]
The turning mode selection valve V2 is incorporated inside the side cover 33 and can be switched by swinging a lever 70 located outside the side cover 33 around the axis of the support shaft 67. The swing link 117 whose free end side is interlocked with the lever 70 by an interlocking rod 116 made of a spring wire is connected to the support portion 113 a of the motor mounting body 113 as a fixed portion fixed to the transmission case 9. It is swingably supported around the core. The swing link 117 is urged by a return spring 119 whose base acts on the swing link 117 to return to a standby position where an intermediate portion of the swing link 117 contacts the stopper 113 b of the motor mounting body 113. When the swing link 117 is at the standby position, the lever 70 is operated to the clutch position by the self-restoring force of the turning mode selection valve V2. Then, the turning mode selection valve V2 is on the clutch side. An operation cam portion 120 for the swing link 117 is provided by fixing a bent wire to the side surface of the rotary cam 114. When the rotation cam 114 is rotated from the neutral position in the forward rotation direction or the reverse rotation direction, the operation cam portion 120 is switched after the steering switching valve V1 is switched to the left or right turning side. The swing link 117 abuts on a free end side portion of the swing link 117 that is larger in distance from the swing axis than the portion to which the interlocking rod 116 is connected, and the swing link 117 is brought into contact with the return spring 119. In opposition, the swing operation is performed to the side away from the stopper portion 113b. Then, the swing link 117 swings the lever 70 to the brake side via the interlocking rod 116, and the lever 70 switches the turning mode selection valve V2 to the brake side. Even if the rotary cam 114 further rotates after the turning mode selection valve V2 reaches the stroke end, the coil spring portion 116a provided on the interlocking rod 116 is elastically deformed to the extension side, and the operation cannot be performed by the turning mode selection valve V2. No power is applied.
[0042]
As shown in FIG. 12, the electric motor 110 and the variable relief valve V4 are connected to a steering lever 42 as a steering operation tool provided on a handle tower 41 of the steering section 7, a steering control means 43, and a mechanical type They are linked by a steering control mechanism 122 having an interlocking mechanism 121.
[0043]
As shown in FIGS. 13 and 14, a support shaft 45 is rotatably mounted on a bracket 44 mounted on the upper right side (as viewed from the driver) of the handle tower 41 so as to be rotatable around a fulcrum x. The steering lever 42 is mounted on a fulcrum fitting 46 connected to the rear end of the support shaft 45 so as to be swingable about a lateral fulcrum y, and the steering lever 42 is configured to be able to swing crosswise. A first operating arm 47 formed by bending a bar into an L shape is projected from the fulcrum fitting 46, and a second operating arm 48 made of a plate is projected from near the front end of the supporting shaft 45. Have been.
[0044]
The first operation arm 47 is linked to a potentiometer 49 as a sensor attached to the handle tower 41 as follows, and the operation of the steering lever 42 and the operation of the steering lever 42 from the neutral position are performed by the potentiometer 49. The direction and operation stroke are electrically detected.
[0045]
In other words, the operating lever 49a of the potentiometer 49 is urged to rotate clockwise in FIG. 13 by a built-in spring so as to always contact the first operating arm 47 from the side. The operation lever 49a follows the first operation arm 47 and rotates while maintaining the contact state, so that the operation position of the steering lever 42 is An output change is continuously detected, and a detection signal is input to the steering control means 43.
[0046]
The steering control means 43 is composed of a microcomputer. When the steering lever 42 is operated, the electric motor 110 is automatically operated based on information from the potentiometer 49 and the steering switching valve V1 and the turning mode selection valve V2. , The left and right side clutches 20L and 20R, the clutch C, and the braking mechanism B are each operated to a state corresponding to the operation position and operation stroke of the steering lever 42.
[0047]
The interlocking mechanism 121 interlocks the steering lever 42 with the variable relief valve V4. The interlocking mechanism 121 includes the second operation arm 48, a pair of operation arms 51 and 52 loosely fitted to the support shaft 45, and the pair of operation arms 51 and 52. A release wire 50, one end of which is connected to the operating arms 51, 52, and an outer end of the inner wire 50b of the release wire 50, which is connected to the free end, and which is swingably provided outside the hydraulic block 37. And the lever 77.
[0048]
The lever 77 serves as an operating portion of the variable relief valve V4, and is pivotally operated around the axis of the support shaft 75 having a double-shaft structure with the support shaft 67, thereby causing the variable relief valve V4 to operate. Manipulate. The lever 77 is urged to swing toward the low pressure side of the variable relief valve V4 by a torsion spring 78 whose one end is locked to the base end of the lever 77.
[0049]
As shown in FIG. 13 and the like, the operating arms 51 and 52 are urged to swing toward each other by a torsion spring 53, and are contacted and supported so as to sandwich a fixing pin 54 provided on the bracket 44. . The free end of one operating arm 51 is connected and supported by the end of the outer wire 50a of the release wire 50, and the free end of the other operating arm 52 is connected to the free end of the inner wire 50b by the release wire 50. The parts are connected and supported. Further, an operation pin 48a provided at the free end of the second operation arm 48 which is swung around the fulcrum x in the front-rear direction by the steering lever 42 is provided between the two operation arms 51 and 52.
[0050]
According to the above configuration, for example, in FIG. 13, when the steering lever 42 is swung from the neutral position n in the right turning direction (left in the drawing), the second operation arm 48 is swung counterclockwise in the drawing, The operation pin 48a pushes one of the operation arms 51 counterclockwise to swing. At this time, since the other operation arm 52 is prevented from swinging counterclockwise due to the contact with the fixing pin 54, the inner wire 50b of the release wire 50 is relatively pulled out from the outer wire 50a. Conversely, when the steering lever 42 is pivoted from the neutral position n in the left turning direction (rightward in the figure), the second operation arm 48 is pivoted clockwise in the figure, and the operation pin 48a is operated in the other direction. The arm 52 is pushed clockwise to swing. At this time, since one of the operating arms 51 is prevented from swinging clockwise by contact with the fixing pin 54, the inner wire 50b of the release wire 50 is pulled out from the outer wire 50a. That is, even if the steering lever 42 is swung from the neutral position n in either the left turning direction or the right turning direction, the inner wire 50b of the release wire 50 is pulled out in accordance with the operation amount, and the wire drawing amount is reduced. The variable relief valve V4 is linked so that the operating pressure increases as the pressure increases.
[0051]
Thereby, the interlocking mechanism 121 operates the variable relief valve V4 to the low pressure side when the steering lever 42 is at the neutral position n, and when the steering lever 42 is swung left and right from the neutral position n, this lever operation is performed. The variable relief valve V4 is operated to the high pressure side by the force, and the variable relief valve V4 is operated to the higher pressure side as the operation stroke from the neutral position n of the steering lever 42 to the left and right increases.
[0052]
The sequence valve V3, the steering switching valve V1, the turning mode selection valve V2, and the variable relief valve V4 will be described in further detail. The sequence valve V3 is incorporated into the hydraulic block 37 together with the steering switching valve V1, the variable relief valve V4 is incorporated into the side cover 33 together with the swing mode selection valve V2, and each valve is provided inside the hydraulic block 37 and the side cover 33. Are connected to each other via an oil passage formed at the bottom.
[0053]
As shown in FIGS. 15 to 18, the steering switching valve V 1 is provided with a spool 61 slidably mounted in the front-rear direction on the upper part of the hydraulic block 37 through the swing link 64 via a support shaft 62 from outside. It is configured to engage with the swingable operation arm 63 to perform a sliding operation.
[0054]
Thus, when the steering lever 42 is at the neutral position n, the rotary cam 114 is at the neutral position, the spool 61 is held neutral by the return spring 65, and the pressure oil supplied from the pump port P After returning to D, it is returned to the mission case 9. When the steering lever 42 is operated in the left turning direction, this is detected by the potentiometer 49, and the electric motor 110 operates the rotating cam 114 to operate the swing link 64, thereby causing the spool 61 to move to the left in FIG. The sliding operation is performed in the direction, and the pressure oil supplied from the pump port P is supplied to the hydraulic actuator 23a of the side clutch 20L for turning left through the oil passage a. When the steering lever 42 is operated in the rightward turning direction, this is detected by the potentiometer 49, and the electric motor 110 operates the rotating cam 114 to operate the swing link 64. The pressure oil supplied from the pump port P is slid to the right in the middle, and supplied to the hydraulic actuator 23b of the right-turn side clutch 20R via the oil passage b.
[0055]
As shown in FIGS. 4 and 19, the turning mode selection valve V2 swings a spool 66, which is slidably mounted in the front-rear direction on the upper part of the side cover 33, from the outside via a support shaft 67 by the lever 70. The operation arm 68 is configured to be contacted and pressed to perform a sliding operation against the spring 69.
[0056]
Thus, when the rotary cam 114 is at the neutral position, the spool 66 is at the position shown in FIG. 19, and the oil passage e on the lower side of the sequence valve V3 is communicated with the oil passage c reaching the clutch C. When the rotary cam 114 is rotated to swing the swing link 117, the swing link 117 swings the lever 70 counterclockwise in FIG. The oil passage e is communicated with an oil passage f reaching the braking mechanism B.
[0057]
As shown in FIG. 19, the variable relief valve V4 has a poppet 71 incorporated in the upper part of the side cover 33 so as to be movable in the front-rear direction. e and a spring receiving member 74 that supports the rear end of the spring 73, and the spring receiving member 74 is externally mounted on the support shaft 67. The relief pressure can be adjusted by abuttingly pressing and slidingly displacing an operation arm 76 which is swingable from the outside by the lever 77 via a support shaft 75 in a shape of a circle. Further, the lever 77 is urged to swing by the torsion spring 78 in a direction to separate the operation arm 76 from the spring receiving member 74. As shown in FIG. At this time, the relief pressure of the variable relief valve V4 is substantially zero. As described above, when the steering lever 42 is swung left and right to pull the inner wire 50b of the release wire 50, the operation arm 76 is swung counterclockwise in FIG. As the member 74 is pushed in and displaced, the swing amount of the steering lever 42 increases, and the wire pulling amount increases, the relief pressure of the variable relief valve V4 gradually increases.
[0058]
Thus, when the steering control mechanism 122 operates the steering lever 42, the electric motor 110 is automatically operated by the action of the potentiometer 49 and the steering control means 43, and the steering switching valve V1 is operated by the electric motor 110. In addition, by operating the turning mode selection valve V2 and operating the variable relief valve V4 by the action of the interlocking mechanism 121, the straight traveling state in which the aircraft is steered so that the aircraft travels straight in accordance with the operation position of the steering lever 42 is displayed. Or a turning state in which the body is steered so as to change the running direction in a direction equal to the operation direction of the steering lever 42 with a turning radius corresponding to the operation stroke of the steering lever 42.
[0059]
In addition, the vertical movement of the steering lever 42 which can be operated in a cross direction causes the cutting pre-processing unit 3 to move up and down. That is, as shown in FIGS. 13 and 14, a sensor 81 including a potentiometer or a switch for detecting the forward / backward swing of the steering lever 42 and a forward / backward swing of the steering lever 42 are provided on the left and right sides of the extension of the lateral support point y. A torsion spring 82 for urging the neutral position n in the moving direction is provided, and when the sensor 81 detects that the steering lever 42 has been swung forward from the neutral position n, the cutting pre-processing unit 3 is activated. When the sensor 81 detects the lowering operation and the backward swinging operation, the sensor 81 and a drive elevating mechanism (not shown) of the pre-cutting unit 3 are linked so as to raise the pre-cutting unit 3. Have been.
[0060]
Reference numeral 83 in FIG. 2 denotes a stop and parking brake which is provided to act on the end of the third shaft 13, and is operated by depressing a pedal 84 provided at the foot of the control unit 7. The main clutch (not shown) provided in the transmission system from the engine 6 to the hydrostatic continuously variable transmission 8 is disengaged, and the brake 83 is braked. The parking brake can be applied by locking and holding the pedal 84 at the depressed position.
[0061]
The steering apparatus according to the present invention is configured as described above, and the steering operation will be described below.
[0062]
When the steering lever 42 is at the neutral position n, the side clutches 20L and 20R are both in the clutch engaged state, the left and right crawler traveling devices 1L and 1R are driven at the same speed, and the aircraft travels straight.
[0063]
When the steering lever 42 is swung from the neutral position n to one side in the left and right direction, for example, to the first operation region Rc on the right side, this is detected by the potentiometer 49, the electric motor 110 is driven, and the rotation cam 114 is rotated. Then, the steering switching valve V1 is switched to the right turning position, the pressure oil is supplied to the oil chamber h via the oil passage b, and the side clutch gear 23R is shifted to the clutch disengagement position by the hydraulic actuator 23b. The side clutch 20R is disengaged. Therefore, only the right crawler traveling device 1R enters the idle state, and only the left crawler traveling device 1L is driven to appear in a gentle turning state, and the aircraft slowly turns rightward.
[0064]
In this case, in the left turning clutch 90L in which the side clutch 23L is not disengaged, low torque is transmitted via the spring 100L, and a part of the power of the side clutch gear 23L is transmitted to the steering side gear 25L. This is transmitted through the gear 27L, the fifth shaft 26, the gear 27R, and the steering side gear 25R to the right turning clutch 90R. Then, the wraparound power is transmitted to the side clutch gear 23R at the clutch disengaged position by light friction transmission via the spring 100R, and the right crawler traveling device 1R receives low torque power transmission. Accordingly, the right crawler traveling device 1R receives the low-torque power transmitted from the power of the left traveling device 1L and operates the side clutch 23R to be disengaged, and the side clutch 23R is disengaged to transmit the main power. As a result, the crawler traveling device 1R does not completely stop due to the traveling load as soon as the side clutch 23R is disconnected, and the shock accompanying the disengagement operation of the side clutch 23R is reduced.
[0065]
When the right side clutch 20R is disengaged, the pressure oil in the oil chamber h is also supplied to the oil chamber j of the right turning clutch 90R via the communication oil passage m, and the turning clutch 90R is turned on. However, while the steering lever 42 is in the first operation range Rc, the operating pressure of the variable relief valve V4 is still low, so that the clutch C is in a state of receiving the supply of hydraulic oil via the mode switching valve V2. Does not engage the clutch, and the steering side gear 25R is not driven. Therefore, in this state, the turning clutch 90R is engaged, but is not involved in the steering of the machine.
[0066]
When the steering lever 42 is operated to the second operation range Rs, the variable relief valve V4 is operated by the interlocking mechanism 12, and the relief pressure of the variable leaf valve V4 becomes greater than the operating pressure of the sequence valve V3. The high-pressure oil is supplied to the hydraulic piston 32 of the clutch C via the oil passage e and the oil passage c, and the clutch C is engaged to operate the steering side gear 25R at a predetermined low speed. Accordingly, the low speed power of the steering side gear 25R is transmitted to the side clutch 20R at the clutch disengaged position via the turning clutch 90R, and the right crawler traveling device 1R is driven in a low speed state reduced at a predetermined ratio. The first turning state appears, and the aircraft slowly and reliably turns rightward based on the driving speed difference between the left and right crawler traveling 1R and 1L.
[0067]
In this case, when the steering lever 42 at the neutral position n is operated all at once to the second operation range Rs, as described above, the right side clutch 20R is disengaged, the clutch C is immediately engaged, and the right turn is performed. Oil in the oil chamber h in the right side clutch 20R passes through a communication oil path m having a throttle channel portion q, and the oil chamber having a large cross-sectional area in the turning clutch 90R. j, the turning-on clutch 90R is operated slowly and smoothly. Therefore, the power transmitted to the steering side gear 25R via the clutch C is transmitted to the side clutch gear 23R without an impact, and the right crawler traveling device 1R smoothly enters the deceleration driving state.
[0068]
Here, since the hydraulic pressure applied to the clutch C is limited by the variable relief valve V4, the hydraulic pressure applied to the clutch C decreases as the steering lever 42 in the second operation range Rs is closer to the neutral position n. , The torque transmitted through the clutch C is small, and as the steering lever 42 in the second operation range Rs moves away from the neutral position n, the hydraulic pressure applied to the clutch C increases, and the right crawler through the clutch C The torque transmitted to traveling device 1R gradually increases. Eventually, the clutch C is completely connected, and the right crawler traveling device 1R is driven at a low speed in which the speed is reduced at a predetermined ratio.
[0069]
When the steering lever 42 is operated beyond the second operation range Rs to the third operation range Rb, this is detected by the potentiometer 49, the electric motor 110 is further driven, and the rotary cam 114 is further rotated to operate in the turning mode. The selection valve V2 is switched, the oil passage e is connected to the oil passage f, the pressure oil is supplied to the hydraulic piston 34 of the braking mechanism B, and the oil passage c is connected to the drain passage D to disengage the clutch C. . In this case, since the relief pressure has already been increased due to the large operation of the steering lever 42, the fifth shaft 26 is braked by the braking mechanism B, and In a state where the braking of the crawler traveling device 1R is stopped, a second turning state in which only the left crawler traveling device 1L is driven appears, and the aircraft makes a sharp turn rightward (a pivot turn).
[0070]
Also, when the steering lever 42 is returned to the neutral position n from the aircraft steering state, the disengaged right side clutch 23R is engaged and returns to the straight traveling state. In the clutch turning clutch 90R, a low torque is transmitted, and the right side clutch gear 23R is slightly rotated. Therefore, the speed difference between the center gear G11 and the side clutch gear 23R causes the side clutch gear 23R to stop. The side clutch gear 23 </ b> R smoothly re-engages with the center gear G <b> 11 without causing poor occlusion.
[0071]
Needless to say, even when the steering lever 42 is operated in the left turning direction, a gentle turning state in which only the left side clutch 20L is disengaged appears in the first operation range Lc in the same manner as described above. A left turn is performed, and in the second operation area Ls, a first turning state in which the clutch C is operated to decelerate and drive the left crawler traveling device 1L appears, a left turn is performed, and a third operation is performed. In the area Lb, a sharp left turn is performed after the second turning state in which the left crawler traveling device 1L is braked appears.
[0072]
The present invention can be implemented in the following forms.
[0073]
(1) In the above embodiment, the left and right swingable steering lever 42 is used as the steering operation tool. However, a steering wheel that is rotated can be used as the steering operation tool. Therefore, these are collectively called a steering operation tool.
[0074]
(2) The side clutch gears 23L, 23R of the side clutches 20L, 20R may be configured to be shifted externally by a pair of shift forks. In this case, the shift forks may be operated by hydraulic cylinders provided respectively.
[0075]
(3) Instead of the braking mechanism B, a reverse rotation transmission mechanism that transmits a driving force in the reverse rotation direction to the other traveling devices 1R, 1L is provided to one traveling device 1L, 1R, and a third operation area for turning is provided. Lb and Rb can also be implemented by setting the traveling device on the side where the side clutch is disengaged to the super pivot turning mode in which the traveling device is decelerated and reversed.
[0076]
(4) In addition to the braking mechanism B and the clutch C, the reverse rotation transmission mechanism is also provided to brake the third operating range Lb, Rb to the traveling device on which the side clutch is disengaged as described above. In addition, it is also possible to provide a fourth operation area in the super pivot turning mode in which the traveling device on the side where the side clutch is disengaged is driven to decelerate and reversely rotate further outside the third operation areas Lb and Rb.
[Brief description of the drawings]
FIG. 1 is a right side view of the entire combine.
FIG. 2 is a schematic view showing a transmission structure of a traveling mission case.
FIG. 3 is a longitudinal sectional front view showing an upper half of a transmission case.
FIG. 4 is a longitudinal sectional front view showing a lower half of a transmission case.
FIG. 5 is an enlarged longitudinal sectional front view of the vicinity of a side clutch.
FIG. 6 is a side view showing an operation structure of the subtransmission mechanism.
FIG. 7 is a vertical cross-sectional front view of a shifter that operates a subtransmission mechanism.
FIG. 8 is a longitudinal sectional front view of a main part showing a state where the sub transmission mechanism is switched to a low speed.
FIG. 9 is a longitudinal sectional front view of a main part showing a state where the sub transmission mechanism is switched to a medium speed.
FIG. 10 is a longitudinal sectional front view of a main part showing a state in which the auxiliary transmission mechanism is switched to neutral.
FIG. 11 is a longitudinal sectional front view of a main part showing a state in which the subtransmission mechanism is switched at a high speed.
FIG. 12 is a configuration diagram of a hydraulic circuit for steering and a control system.
FIG. 13 is a front view of a steering operation unit.
FIG. 14 is a side view of a steering operation unit.
FIG. 15 is a side view showing an arrangement portion of the motor.
FIG. 16 is a front view showing an arrangement portion of the motor.
FIG. 17 is a longitudinal sectional side view showing the periphery of a steering switching valve.
FIG. 18 is a front view showing an operation unit of the steering switching valve.
FIG. 19 is a longitudinal sectional side view showing the periphery of a mode switching valve and a variable relief valve.
[Explanation of symbols]
1L, 1R traveling device
20L, 20R side clutch
23a, 23b Hydraulic actuator for clutch
32 1st hydraulic actuator for turning
34 Second hydraulic actuator for turning
42 Steering operation tool
43 Steering control means
49 sensors
64 swing link
110 electric motor
113a Fixed part
114 rotating cam
115 Operation cam section
116 Interlocking rod
117 Swing Link
121 Linkage mechanism
122 Steering control mechanism

Claims (3)

It is equipped freely operated separately by a pair of left and right traveling devices (1L) (1R) pair of side clutches acting on each other in (20L) (20R) is a hydraulic actuator for a pair of clutch (23a) (23b), the side clutch First turning means (C) for changing the running direction of the body (2) by turning the running device (1L) inside the turning direction by changing the running direction of the running device (1L) by decelerating or braking the running device (1L) from which the (20L) is cut off Is turned on and off by a first hydraulic actuator for turning (32), and the traveling device (1L) is turned by braking or reversely driving one traveling device (1L) with the side clutch (20L) disengaged. A second turning means for changing the running direction of the body (2) to the inside and with a smaller turning radius than when turning by the first turning means (C); The B), a steering apparatus for agricultural machines are provided with operating freely turns on and off by a second hydraulic actuator for turning (34),
A steering switch including a sensor (49) for detecting an operation direction and an operation stroke from a neutral position of one of the steering operation tools (42), and operating the pair of clutch hydraulic actuators (23a) and (23b); (V1) and an operation of switching a turning mode selection valve (V2) for selectively connecting the first turning hydraulic actuator (32) and the second turning hydraulic actuator (34) to a hydraulic supply source. comprising a single electric motor for direction (110), wherein the sensor automatically operated to steering control means to the electric motor (110) based on information from (49) (43), the swivel mode select valve A steering control mechanism (122) having a mechanical interlocking mechanism (121) for interlocking a steering operation tool (42) with a turning control valve (V4) for controlling hydraulic pressure supply to (V2) is provided. When When the steering operation tool (42) is operated to the neutral position, the pair of side clutches (20L) and (20R) is engaged, and the first turning means (C) and the second turning means are operated. When the steering operation tool (42) is operated left or right from the neutral position, the turning control valve (V4) is turned on via the mechanical interlocking mechanism (121). ) Is operated to supply hydraulic pressure to the turning mode selection valve (V2), and based on detection of an operation direction and an operation stroke from a neutral position of the steering operation tool (42) by the sensor (49). The one electric motor (110) is operated, and based on the operation of the member (114) interlocked with the forward / reverse rotation of the electric motor (110), the steering switching valve (V1) turns left or right. Switched to the steering side Both the electric motor (110) of the reverse rotation to the though turning the mode select valve (V2) First is controlled switching in the same direction, becomes the steering clutch of one of the traveling device (1L) (20L) is cut, and A first turning state in which the first turning means (C) is turned on and the second turning means (B) is turned off appears, and the steering operation tool (42) is operated left or right. Then, the side clutch (20L) of one traveling device (1L) is disengaged, the first turning means (C) is disengaged, and the second turning means (B) is turned on. A steering device for an agricultural work machine, wherein the steering control mechanism (122) is configured so that a second turning state appears. The rotation switching valve (V1) is oscillated by a rotary cam (114) that is rotated forward and reverse by the electric motor (110) and an operation cam section (115) provided on the peripheral surface of the rotary cam (114). 2. The steering apparatus for an agricultural work machine according to claim 1, further comprising a swing link (64) for performing a switching operation of (a). The rotating cam (114) rotated by the electric motor (110) and the fixed portion (113a) in a state where the free end abuts on the rotating cam (114) and is swingably operated by the rotating cam (114). A swinging link (117) supported swingably, and an interlocking rod (117) linking the free end side of the swinging link (117) to the operating section (70) of the turning mode selection valve (V2). The steering device for an agricultural work machine according to claim 1 or 2, further comprising (116).

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