JPH0571080U - Four-wheel steering switching mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] In a traveling vehicle equipped with a work machine that can steer the front and rear wheels, it is configured to maintain straightness during work and to change direction by a sharp turn in a headland etc. Then, it enables stable work. [Structure] A switching member is arranged at an arbitrary position of an elevating mechanism of a working machine, the switching member is connected to a steering device, and front and rear wheels are steered in the same phase when the working machine is descending, and opposite phases are steered when the working machine is rising. It should be configured accordingly.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a technique for switching the four-wheel steering of a transplanter such as a rice transplanter or a traveling vehicle such as a tractor equipped with a working machine to the same phase or an opposite phase according to the elevation of the working machine.

[0002]

[Prior Art]

 Most conventional traveling vehicles such as transplanters have a structure in which only the front wheels are steered. In recent years, a technology has been known in which the front and rear wheels can be steered so that a sharp turn can be made on a headland or the like. Is becoming.

[0003]

[Problems to be solved by the device]

 However, even if the configuration is such that four-wheel steering is possible, the speed-sensitive type may have a slow operating speed, so the front and rear wheels can be rotated in phase or in reverse depending on the turning angle of the steering wheel. In the case of a moving configuration, if the steering wheel is turned slightly larger to greatly correct the traveling direction due to unevenness etc., the front and rear wheels will be steered in the opposite phase and the front and rear wheels will turn in opposite directions. However, when the steering of the front wheels is turned off, the tail swing becomes large and the swinging on both sides of the work machine is large, which may damage the crops, resulting in a decrease in yield. That will be the case. Also, in the headland, the steering wheel is once steered in the same phase and then the rear wheels are rotated in the opposite phase, so that the headland is dug up and the leveling is impaired. Had become.

[0004]

[Means for Solving the Problems]

 The present invention uses the following means in order to solve the above problems. That is, in a traveling device having a working machine configured to be able to steer both front and rear wheels, a switching member is arranged at an arbitrary position of the lifting mechanism of the working machine, the switching member is connected to the steering device, and The front and rear wheels are steered in opposite phases when ascending and in the same phase when descending.

[0005]

[Action]

 In the case of rush transplanter, while the planting work is going straight, the planting part is descending, so the front and rear wheels are in phase steering, and the rear wheels turn in the same direction when the front wheels are broken. As a result, there is little deviation in the direction of the machine and good straightness. When changing direction on a headland, etc., the planting claws, etc. are moved away from the ground to raise the planting section, so the front and rear wheels are in anti-phase steering, and a stable and rapid turn is possible. The machine can be oriented in the desired direction without damaging the seedlings, and the distance between the planting seedlings in the previous stroke and the next stroke can be accurately maintained.

[0006]

【Example】

 The problems and configurations to be solved by the present invention are as described above. Next, an embodiment in which the switching device of the present invention is provided in the grass transplantation shown in the accompanying drawings will be described. Fig. 2, Fig. 2 is a side view showing in-phase and anti-phase steering switching of front and rear wheels by wire system, Fig. 3 is a side view showing in-phase and anti-phase steering switching of front and rear wheels by limit switch system, and Fig. 4 is hydraulic pressure. Hydraulic control circuit for front and rear wheel steering by cylinder system, Fig. 5 is a plan view showing the arrangement of tie rod cylinders, Fig. 6 is a plan view showing another arrangement of tie rod cylinders, and Fig. 7 is a transmission unit in Fig. 6. Fig. 8 is a hydraulic control circuit diagram for front and rear wheel steering using the tie rod cylinder system, Fig. 9 is a plan view of the transmission system for front and rear wheel steering using the clutch system, and Fig. 10 is a side view in Fig. 9. 12 is a rear view of the planting part P, FIG. 12 is a plan view of the seedling joint sensor 5 and the stopper 7, FIG. 13 is a side view of the same, FIG. 14 is a plan view of a lever guide of the main shift lever, and FIG. Fig. 16 is a perspective view of a grass transplanter that wants to straddle the arch 32, Fig. 16 is a partial perspective view of an attachment portion of the arch to the crushed preliminary seedling stand, and Fig. 17 is an arch of the preliminary seedling stand equipped with the stopper 33. 18 is a partial perspective view of the mounting portion, and FIG. 18 is a perspective view of a grass transplanter for supporting the preliminary seedling stand at step 34.

First, the structure of the rush transplanter will be described. As shown in FIG. 1, a planting section P including a seedling platform 3 and planting claws 4 is connected to a rear side of the traveling machine S by a link mechanism L so that the planting section P can be moved up and down. I am doing it. M is a marker that descends onto the field during work and scratches the soil surface along the side edges of the planting line to make a mark, which serves as a guide for the course of planting work in the next step. As shown in FIG. 11, in the transplanting section, the grass seedlings are placed on the seedling mounting table 3 and are forcibly conveyed downward by the belt 3a, and the grass seedlings that come to the bottom position are rotated. The nails 4 are grasped and planted on the field. During that time, the rush seedlings on the seedling stand 3 are sent downward one after another, and the transplanting is repeated.

[0008] In this way, as the transplanting work progresses, the rush seedlings on the seedling mounting table 3 will disappear, but if the planting work is still performed in this state, empty planting, that is, a missing plant will occur. Therefore, it is necessary to have a means to notify the person when it comes to this state. Therefore, as shown in FIGS. 11 to 13, conventionally, a whip-shaped seedling splicing sensor 5 is provided on the rib 3b for partitioning the rush seedlings on the seedling placing table 3 into an appropriate row, and the rush seedlings are placed on the seedling placing table 3. While it remains on 3, the seedling splicing sensor 5 is pressed and rotated downward, and the sensor switch is OFF. When the rush seedlings are exhausted, the whip-like seedling splicing sensor 5 rotates to the upper position A by its restoring force, which turns on the sensor switch, and the alarm buzzer arranged near the driver's seat as shown in Fig. 1. 6 is sounded.

However, in such a conventional seedling splicing sensor, when the residual seedlings on the seedling mounting table 3 are removed at the end of the work, the residual seedlings and the clothes of the worker are erected upward. The seedling succession sensor 5 is often touched, and if it is bad, it may damage the sensor. Moreover, since the sensor remained in the ON state during the removal work, the alarm buzzer 6 continued to sound, which was very annoying. Therefore, in this embodiment, as shown in FIGS. 12 and 13, when a stopper 7 made of a bolt is provided on the side surface of the rib 3b and the seedling splicing sensor 5 is rotated to the B position, the sensor moves upward. The restoring force pushes the stopper 7 to fix the sensor switch in the OFF state. In this way, if the seedling splicing sensor 5 is fixed to the stopper 7 during the removal work of the remaining seedlings, the above problems do not occur.

Next, the traveling machine S will be described. First, since the rush transplanter is the same in structure as the rice transplanter, the traveling machine S often uses the rice transplanter. In this example, the machine of the rice transplanter is also used, but the problem here is that in the case of rice planting, since the seedlings on the seedling mounting table are sent and planted, seedling feeding and planting nails are required. The seedlings can be smoothly picked up and the planting work can be performed at high speed.However, in the case of rush transplanting, since the saplings are placed in a disjointed state on the seedling stand, high-speed operation is not possible. However, the feeding of seedlings and the removal of seedlings from the planting claws become unsuccessful, making it impossible to plant properly. Therefore, in the case of transplanting rush, as shown in FIG. 14, the lever guide 8a of the main speed change lever 8 is covered and fixed with the restriction plate 9 so that the lever is not moved to the high speed position so as not to operate at high speed. I try not to send it.

In the transmission of FIG. 14, the traveling speed of the traveling machine S at the time of planting work is a three-speed type, but the regulation plate 9 should be formed in a Y shape so that both ends are fixed. The 2nd speed position 8c and the 3rd speed position 8d are covered by this so that the lever can be sent only to the 1st speed position 8b during the planting work. In the OFF position, the driving clutch of the planting part P is disengaged, the N position is the neutral position, and the planting part P is raised by sending the lever to the U position. In this way, by covering the high speed position with the regulation plate 9, it is possible to prevent a situation in which the main transmission lever 8 is mistakenly sent to the high speed position during transplantation of the grass to cause a transplant error. The left and right markers M of the planting part P shown in FIG. 1 can be lowered to the field by sending the main shift lever 8 to the left and right positions MR and ML of the first speed position 8b, and the regulation plate 9 is The shape is such that the marker set position is not covered. Further, notches 9a are formed at both ends of the regulation plate 9 so that they can be easily attached and detached, and the notches 9a are engaged with the mounting bolts of the guide.

In the traveling machine S of the present invention, both the front wheels 1 and the rear wheels 2 can be steered by operating the steering wheel 10, and can be switched to the opposite phase when the seedling table 3 is raised and the same phase steering when the seedling table 3 is lowered. It has a structure of. First, means for switching between in-phase steering and anti-phase steering by raising and lowering the seedling placing table 3 will be described with reference to FIGS.

FIG. 2 is based on the wire system. That is, in the link mechanism L connecting the planting section P such as the seedling placing table 3 to the traveling machine S, one end of the wire W is fixed to an arbitrary position of the upper link L1, for example, the rotation fulcrum LP. The wire W is composed of an outer wire Wa and an inner wire Wb. The outer wire Wa is fixed by a stopper Wc at a link L, and one end of the outer wire Wa is connected to a rotation fulcrum LP of the upper link L1. Then, the other end is connected to the isophase / antiphase switch S1 which is switched when pulled. With this configuration, when the planting portion P is raised, the wire W is pulled by the upward rotation at the rotation fulcrum LP, and the front / rear wheel steering changeover switch S1 is actuated to perform the reverse phase steering. Then, as the seedling table 3 descends, the rotation fulcrum LP returns to the original link pivotal state, the inner wire Wa returns to the original state, and the front / rear wheel steering changeover switch S1 is set to the in-phase steering setting. Can be switched to.

Further, FIG. 3 shows a configuration of the limit switch LS1. That is, the leaf spring 11 and the limit switch LS1 are provided on the link L, and when the seedling placing table 3 rises, the leaf spring 11 presses against the limit switch LS1 to turn it on. Then, when the limit switch LS1 is ON, reverse phase steering is performed, and when no input is made, that is, when the seedling placing table 3 is being lowered, the same phase is achieved, for example, as shown in FIG. A front / rear wheel steering switching solenoid valve SV1 is configured as a changeover switch. In addition, C is a control apparatus.

Next, three examples of the configuration of front and rear wheel steering (4WS) will be described. First, a hydraulic steering method will be described with reference to FIG. The front wheels 1 are hydraulically steered as power steering. The hydraulic oil sent from the hydraulic pump 12 from the oil tank T attached to the engine E is sent to the front wheel steering cylinder OC1 and the rear wheel steering cylinder OC2 from the steering valve SV2 which is switched by the steering of the steering wheel 10. The expansion and contraction of the piston rods of both steering cylinders OC1, 2 causes the bell cranks 13, 14 to rotate, and the left and right tie rods 15L, 15R, 16L, 16R of the front and rear wheels, respectively, to rotate the front wheel 1 And the rear wheel 2 is turned. In this embodiment, the limit switch LS1 shown in FIG. 3 is used as the steering switching means having the same phase as the opposite phase when the planting part P is moved up and down, and the front / rear wheel steering switching solenoid is switched by the switch. The valve SV1 is provided in the oil passage extending from the steering valve SV2 to the rear wheel steering cylinder OC2.

The planting part raising / lowering valve SV3 for operating the link L that moves up and down the planting part P such as the seedling mounting table is supplied with pressure oil after being sent to the steering valve SV2. However, in the configuration as shown in the figure, the oil is not fed only when the steering is in the straight traveling state, and the planting portion P moves up and down when turning the direction to damage the planting claw 4. , It prevents the planted shoots from being distorted.

As described above, in FIG. 4, the rear wheels 2 are steered by hydraulic pressure similarly to the power steering mechanism of the front wheels 1, but in this case, the cutting angle of the rear wheels 2 is difficult to obtain with accuracy. Therefore, the corner angle of the rear wheel 2 is made smaller than that of the front wheel 1 to deal with it. This steering method has the advantages that the structure is simple and the cost is low.

Next, a steering method in which a hydraulic tie rod cylinder is arranged between the front and rear tie rods will be described. First, as shown in FIG. 5, the knuckle arm 17 of the front wheel 1 on the same side of the knuckle arm 18 of the rear wheel 2 has the rod 19 on which the tie rod cylinder TC1 for the same phase is arranged, and the knuckle of the front wheel 1 on the opposite side. A rod 20 in which a reverse phase tie rod cylinder TC2 is arranged is connected to the arm 17b.

Another embodiment of the arrangement of the tie rod cylinders will be described with reference to FIGS. 6 and 7. The propeller shaft PS is connected from the bell crank 13 of the front wheel 1 via a bevel gear, and the other end of the shaft is inserted into and meshed with the bevel gear box VB of the rear wheel 2 as a bevel gear. Links 21 and 22 are respectively attached from bevel gears V1 and V2 that mesh vertically in the box VB, and from the respective links to the knuckle arm 18 'of the rear wheel 2, from the link 21, a tie lock for same phase is provided. The rod 23 in which the de-cylinder TC1 'is arranged is connected from the link 22 to the rod 24 in which the anti-phase tie rod cylinder TC2' is arranged as shown in the drawing.

FIG. 8 shows a hydraulic circuit diagram in the tie rod cylinder system. The front wheels 1 are of the power steering type having the same structure as in FIG. The structure of the planting section raising / lowering valve is also the same, and the pressure oil sent from the oil tank T of the engine E to the steering valve SV2 by the hydraulic pump 12 is sent to the planting section raising / lowering valve SV3. Part of the oil is used to drive the tie rod cylinders TC1 and TC2. First, a front / rear wheel steering switching solenoid valve SV1 'which is switched by the method shown in FIG. 3 as the planting portion P is moved up and down is arranged in the oil passage to the tie rod cylinder. By switching the solenoid valve SV1 ', the pressure oil is sent to one cylinder to fix the piston in the cylinder, and the rod in which that cylinder is arranged functions as a tie rod, while the other cylinder is operated. By allowing the pressure oil to come in and out freely and to expand and contract, the rod in which the cylinder is installed does not function.

In the case of FIG. 8, the pressure oil is sent to the tie rod cylinder TC1 (TC1 ′) for isotope as the planting section P such as the seedling placing table descends, so that FIG. When the rod 19 (23) in FIGS. 6 and 7 is fixed and, for example, the front wheel 1 is cut to the right, the knuckle arm 18 (18 ') is moved from the knuckle arm 17a (link 21) via the rod 19 (23). Rotate to rotate the rear wheel 2 to the right. At this time, the reverse phase tie rod cylinder TC2 (TC2 ') allows the pressure oil to flow in and out freely, so that even when the front wheel 1 is rotated to the right and the rear wheel is rotated to the right, the rod 20 is rotated. Since the rod 20 (24) freely extends (the rod 24 freely contracts), the rod 20 (24) does not hinder the rotation of the front and rear wheels. Therefore, in this case, the front and rear wheels are smoothly steered in the same phase.

Similarly, when the planting portion P moves up and the front / rear wheel steering switching solenoid valve SV1 ′ is switched, hydraulic oil is sent to the anti-phase tie rod cylinder TC2 (TC2 ′) and the rod 20 (24) is fixed and functions as a tie rod, while the in-phase tie rod cylinder TC1 (TC1 ') allows pressure oil to come and go, so the rod 19 (23) is not fixed, and therefore the front and rear The wheels will be steered in opposite phase. However, when fixing the tie rod cylinder, it is fixed at the straight position.

In the steering method using the tie rod cylinder system as described above, the rear wheel is rotated mechanically by the rod with respect to the cutting angle of the front wheel, so that the cutting angle of the rear wheel also strictly corresponds. Therefore, the turning angle of the rear wheels can be made large, and an accurate direction change can be realized in the reverse phase steering during a sharp turn.

As the final method of steering the front and rear wheels, the clutch system shown in FIGS. 9 and 10 will be described. That is, when the steering wheel 10 is operated, the front wheel steering cylinder OC1 is expanded and contracted, the bell crank 13 is rotated, and the bevel gear 25 is rotated through the bevel gear and the propeller shaft PS, and the bevel gear 25 is in-phase. 26 and an anti-phase bevel gear 27. A rear wheel steering shaft 28 is passed through both bevel gears via a clutch. When the clutch 26a attached to the in-phase bevel gear 26 is ON, the rear-wheel steering shaft 26 is rotated in the rotating direction of the in-phase bevel gear 26. When the shaft 28 rotates and the clutch 27a is ON, the bevel gear 27 for antiphase rotates in the rotating direction. The rear wheel steering shaft 28 is connected to a rear wheel bell crank 29, and the rotation thereof causes the bell crank 29 to rotate, thereby turning the rear wheel.

When the clutches 26a and 27a are switched, the clutch plate 30 is turned on in response to the raising and lowering of the planting part P. In FIG. 10, the method of the wire W of FIG. 2 is adopted. The clutch plate 30 meshes with the clutch 26a when the vehicle is descending, and the front and rear wheels are steered in phase. However, when the planting part P is raised, the wire W is pulled and the clutch plate 30 meshes with the clutch 27a. However, the front and rear wheels are steered in opposite phase. That is, the clutch plate 30 corresponds to the front / rear wheel steering changeover switch S1 in FIG.

As shown in FIG. 15, the auxiliary seedling stand reinforcements arranged on the right and left sides of the traveling machine S of the grass transplanter having the steering mechanism for the front and rear wheels are arranged on the right and left sides of the traveling machine S, respectively. When the seedlings on the seedling placing table 3 of the planting section P are exhausted, the seedlings on the spare seedling placing table 31 are replenished. This spare seedling stand 31 is made of a normal pipe material, and in order to reinforce it, conventionally, an arch 32 made of a pipe material was inserted into the pipe materials of the left and right spare seedling stand 31 and straddled. Of. However, in the case of this conventional technique, it is impossible to put a garage or stack trucks in two stages with the arch 32 standing upright. Therefore, even if the arch 32 is removed, the pipe material is hard to remove and is difficult to remove. A place to put the arch 32 after is also necessary.

In order to eliminate such a problem, for example, as shown in FIG. 16, the arch 32 and the column member mounting portion of the preliminary seedling stand 31 are crushed to be attached and detached with bolts and nuts. In this case, the arch 32 can be easily removed, and if the arch 32 is folded down and bolted to the preliminary seedling stand 31, the labor of placing the removed arch somewhere can be saved. Further, in the structure in which the arch 32 is locked to the preliminary seedling stand 31 with a pin or the like, the L-shaped stopper 33 is attached as shown in FIG. 17, and the 33a portion is pressed against the arm 32 when standing up and the 33b portion when lying down. It has a structure for fixing the arm. Further, the arm 32 is attached to the preliminary seedling stand 31 in an upright state or a fallen state by the locking pin 34. Further, in FIG. 18, the arch is abolished, and the step 35 for getting on and off the cab is formed into a shape as shown to support the preliminary seedling stand 31.

[0028]

[Effect of the device]

 The present invention has the following effects by being configured as claimed. In other words, in the front-rear wheel steering type traveling device, when the work machine descends, it is operating straight ahead.At this time, since the front and rear wheels are in-phase steering, even if the front wheel is slightly broken, the rear wheel Since the sides cut in the same direction in correspondence, the work piece does not move in the same direction and is stable straight. In addition, when the working machine rises, the machine makes a sharp turn in a headland, and at this time the front and rear wheels are steered in opposite phases, so the sharp turn is smooth and stable. The radius is also small. Therefore, clean transplantation and planting work can be performed without the boundaries between the work marks of the previous process and the work processes of the next process overlapping or too far apart. As described above, the work is performed functionally, the growth of crops is improved, and the yield is increased.

[Brief description of drawings]

FIG. 1 is an overall side view of a grass transplanter.

FIG. 2 is a side view showing in-phase / anti-phase steering switching of front and rear wheels by a wire system.

[Fig. 3] Same phase of front and rear wheels by limit switch method
It is a side view which shows reverse phase steering switching.

FIG. 4 is a hydraulic control circuit diagram of front and rear wheel steering using a hydraulic cylinder system.

FIG. 5 is a plan view showing an arrangement configuration of a tie rod cylinder.

FIG. 6 is a plan view showing another arrangement configuration of the tie rod cylinders.

7 is a side view of the transmission system in FIG.

FIG. 8 is a hydraulic control circuit diagram for front and rear wheel steering using a tie rod cylinder system.

FIG. 9 is a plan view of a transmission system in front and rear wheel steering by a clutch system.

FIG. 10 is a side view of FIG.

11 is a rear view of the planting section P. FIG.

FIG. 12 is a plan view of a seedling joint sensor 5 and a stopper 7.

FIG. 13 is a side view of the same.

FIG. 14 is a lever guide plan view of the main shift lever.

FIG. 15 is a perspective view of a grass transplanter in which an arch 32 is to be straddled over a preliminary seedling stand 31.

FIG. 16 is a partial perspective view of a mounting portion of an arch to a crushed preliminary seedling stand.

FIG. 17 is a partial perspective view of an attachment portion of an arch to a preliminary seedling stand equipped with a stopper 33.

FIG. 18 is a perspective view of a grass transplanter that supports a preliminary seedling stand in step 34.

[Explanation of symbols]

 S Traveling machine P Planting part L Link 1 Front wheel 2 Rear W wire LS1 Limit switch OC1 Front wheel steering cylinder OC2 Rear wheel steering cylinder TC1, TC1 'In-phase steering tie rod cylinder TC2, TC2' Reverse phase steering tie rod cylinder S1 Front / rear wheel steering switching switch SV1 Front / rear wheel steering switching solenoid valve SV2 Steering valve

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Claims (1)

[Scope of utility model registration request] 1. A traveling device having a working machine configured to be able to steer both front and rear wheels, wherein a switching member is arranged at an arbitrary position of an elevating mechanism of the working machine, and the switching member is connected to the steering device to perform a rear work. A four-wheel steering switching mechanism in which the machine is configured to steer the front and rear wheels in opposite phases when ascending and in the same phase when descending.