JP2023001732A - Traveling vehicle body - Google Patents

Abstract

To provide a traveling vehicle body capable of changing toe angles of left and right front wheels easily and even during traveling because there exists a traveling vehicle body which can execute appropriate work for the left and right front wheels by changing the left and right front wheels to toe-in or toe-out according to conditions of a field, however, conventionally this changes the left and right front wheels to replace with each other for change to toe-in or toe-out and the toe angle change is not easy and the toe angle change cannot be executed during traveling.SOLUTION: A traveling vehicle body having rear wheels as driving wheels and left and right front wheels 7, 7 steered by a steering operation device is provided with: a Pitman arm 27 steering the left and right front wheels 7, 7 in a longitudinal direction through tie rods 32L, 32R by steering operation of the steering operation device; and toe angle change mechanisms 29L, 29R operated by an actuator changing a toe angle of the left and right front wheels 7, 7 by changing a connection position of the tie rods 32L, 32R and the Pitman arm 27.SELECTED DRAWING: Figure 2

Description

The present invention relates to a traveling vehicle body equipped with left and right steerable front wheels.

There is a traveling vehicle body in which the left and right front wheels are changed to toe-in and toe-out according to the conditions of the field so that suitable work can be performed (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2001-299021

Toe-in and toe-out are changed by interchanging the left and right front wheels, and it is not easy to change the toe angle, and the toe angle cannot be changed during running.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a running vehicle body that can easily change the toe angles of the left and right front wheels even during running.

According to the first aspect of the present invention, a traveling vehicle body equipped with a rear wheel 8 which is a drive wheel and left and right front wheels 7, 7 steered by a steering operation device 19 can be operated by steering operation of the steering operation device 19. A pitman arm 27 is provided to steer and rotate the front wheels 7, 7 in the left-right direction via tie rods 32L, 32R. This traveling vehicle body is provided with toe angle changing mechanisms 29L and 29R that are operated by actuators that change the toe angles.

According to the first aspect of the present invention, the pitman arm 27 is provided for steering and rotating the left and right front wheels 7, 7 in the left and right direction via the tie rods 32L, 32R by the steering operation of the steering operation device 19, and the tie rod 32L. , 32R and the pitman arm 27 to change the toe angles of the left and right front wheels 7, 7. The actuators are operated to change the toe angles of the left and right front wheels 7, 7. toe angle can be easily and even while driving.

According to a second aspect of the invention, the toe angle changing mechanisms 29L, 29R are left and right gears 29L, 29R provided on the left and right sides of the rotation shaft 28 of the pitman arm 27 and engaged with each other. 2. The traveling vehicle body according to claim 1, wherein one ends of the tie rods 32L, 32R are connected, and an actuator rotates the left and right gears 29L, 29R to change the toe angles of the left and right front wheels 7,7.

The invention according to claim 3 is the traveling vehicle body according to claim 1 or claim 2, wherein the toe angle changing mechanisms 29L, 29R are provided above the pitman arm 27.

The invention according to claim 4 is the traveling vehicle body according to any one of claims 1 to 3, wherein the actuator is operated by operating the toe angle changing operation tool 35 to change the toe angles of the left and right front wheels 7, 7. be.

According to the fifth aspect of the invention, the slip ratio is calculated by a rotational speed detection device that detects the rotational speed of the rear wheels 8, and when the slip ratio is greater than a standard value, the actuator is operated to drive the left and right front wheels 7,7. is set to toe-in, and when the slip ratio is smaller than a standard value, the actuator is operated to set the left and right front wheels 7, 7 toe-out.

1 is a side view of a riding rice transplanter according to an embodiment of a traveling vehicle body of the present invention; FIG. Fig. 2 is a plan view for explaining the action of the main part of the passenger-type rice transplanter; Fig. 2 is a plan view for explaining the action of the main part of the passenger-type rice transplanter; It is a rear view for operation|movement description of the principal part of a passenger type rice transplanter. Fig. 2 is a plan view for explaining the action of the main part of the passenger-type rice transplanter; Fig. 2 is a plan view for explaining the action of the main part of the passenger-type rice transplanter; Fig. 2 is a plan view for explaining the action of the main part of the passenger-type rice transplanter;

Preferred embodiments of the present invention will be described below with reference to the drawings.

<Overall composition>
FIG. 1 is a side view of a riding-type rice transplanter equipped with a fertilizing device, which is one embodiment of the traveling vehicle body of the present invention. In this riding-type rice transplanter 1 with a fertilizing device, a seedling planting unit 4 is attached to the rear side of a traveling vehicle body 2 via an elevating link device 3 so as to be able to move up and down, and a main body of a fertilizing device 5 is mounted on the rear upper side of the traveling vehicle body 2. is provided. A ground leveling rotor 6 is provided in front of the seedling planting section 4 . Further, on both sides of the front portion of the traveling vehicle body 2 are provided spare seedling mounting bases Y, and at the center of the front end of the traveling vehicle body 2, a center marker CM is provided. The left and right directions of the riding-type rice transplanter 1 are referred to as left and right, respectively, and the forward and backward directions are referred to as front and rear, respectively.

<Running body 2>
The traveling vehicle body 2 is a four-wheel drive vehicle having a pair of left and right front wheels 7, 7 and a pair of left and right rear wheels 8, 8, which are driving wheels. Front wheel final cases 10, 10 are provided on the left and right sides of the case 9 with a caster angle A, and the left and right front wheel final cases 10, 10 are directed outward from the respective front wheel support portions 10a, 10a capable of changing the steering direction. The left and right front wheels 7, 7 are attached to the left and right front wheel axles 10b, 10b, respectively.

A front end portion of a main frame 11 is fixed to the rear portion of the transmission case 9, and left and right rear wheel gear cases 12, 12 are independently movable up and down at the rear end portion of the main frame 11 via left and right suspensions. Rear wheels 8 , 8 are attached to left and right rear wheel axles 13 , 13 projecting outward from left and right rear wheel gear cases 12 , 12 .

The engine 14 is mounted on the main frame 11 , and the rotational power of the engine 14 is transmitted to the mission case 9 via the belt transmission device and the HST 15 . The rotational power transmitted to the mission case 9 is changed in speed by the transmission in the mission case 9, and then separated into traveling power and external power and taken out. A part of the driving power is transmitted to the left and right front wheel final cases 10, 10 to drive the left and right front wheels 7, 7, and the rest is transmitted to the left and right rear wheel gear cases 12, 12 via the left and right rear wheel drive shafts. to drive the left and right rear wheels 8,8. The external extraction power is transmitted to the planting clutch case provided at the rear portion of the traveling vehicle body 2, and then transmitted to the seedling planting unit 4 by the planting transmission shaft, and to the fertilizing device 5 by the fertilizing transmission mechanism. be.

An upper portion of the engine 14 is covered with an engine cover 16, and a seat 17 is installed thereon.

In front of the seat 17, there is a front cover 18 which incorporates various operation mechanisms and has an operation panel 18a at the rear upper part. ing.

Horizontal floor steps 20 are formed on both left and right sides of the lower ends of the engine cover 16 and the front cover 18 . The floor step 20 is partly shaped like a lattice so that the mud attached to the shoes of the worker walking on the floor step 20 falls on the field. The rear portion above the floor step 20 is a rear step 21 that also serves as a rear wheel fender.

The lifting link device 3 has a parallel link structure, and includes one upper link 22a and a pair of left and right lower links 22b, 22b. These links 22a, 22b, and 22b are rotatably attached at their base sides to a back-view portal-shaped link base frame 23 erected at the rear end of the main frame 11, and a vertical link 24 is connected to their tip sides. ing. A connecting shaft 25 rotatably supported by the seedling planting section 4 is inserted into and connected to the lower end of the vertical link 24 , and the seedling planting section 4 is connected to the seedling planting section 4 so as to roll around the connecting shaft 25 . An elevating hydraulic cylinder 26 is provided between the link base frame 23 and the vertical link 24. By extending and contracting the elevating hydraulic cylinder 26 with hydraulic pressure, the elevating link device 3 rotates up and down, and the seedling planting section 4 moves up and down while maintaining a substantially constant posture.

Here, the steering structure of the left and right front wheels 7, 7 will be described in detail with reference to FIGS. 2, 3, 4, and the like.

A pitman arm 27 is provided on the front bottom side of the traveling vehicle body 2 for steering and rotating the left and right front wheels 7, 7 in the left-right direction in response to a steering operation for rotating the handle 19. As shown in FIG. That is, the steering shaft rotates in response to the steering operation for rotating the handle 19, and the pitman arm 27 rotates about the rotation shaft 28 via the pinion mechanism (or the power steering mechanism). do.

In the pitman arm 27, left and right gears 29L and 29R as a toe angle changing mechanism are provided on the left and right upper surfaces of the rotary shaft 28 so as to be rotatable by a drive shaft 30L and a pivot shaft 30R. The rotational position of the driving shaft 30L of the left gear 29L can be changed by a stepping motor provided on the upper surface of the pitman arm 27. By changing the rotational position of the left gear 29L, the right gear 29R meshing with the left gear 29L is also rotated. is changed (details will be described in change of the toe angle of the left and right front wheels 7, 7 below).

Left and right gears 29L and 29R are provided with taper holes 31L and 31R, respectively, and pin bodies 33L and 33R provided at one ends of left and right tie rods 32L and 32R are inserted into the taper holes 31L and 31R to engage and connect. .

The other ends of the left and right tie rods 32L, 32R are engaged and connected to left and right plates 34L, 34R fixed to the left and right front wheel support portions 10a, 10a capable of changing the steering direction of the left and right front wheel final cases 10, 10, respectively.

As a result, by steering the handle 19, the pitman arm 27 rotates about the rotation shaft 28, and engages with the left and right gears 29L and 29R provided on the left and right upper surfaces of the rotation shaft 28 of the pitman arm 27. The left and right front wheel support portions 10a, 10a capable of changing the steering direction of the left and right front wheel final cases 10, 10 are rotated in the left and right direction through the connected left and right tie rods 32L, 32R to rotate the left and right front wheels 7, 7 in the left and right direction. Steer and rotate.

Next, the change of the toe angles of the left and right front wheels 7, 7 will be described in detail.

A left gear 29L provided on the pitman arm 27 can change its rotational position by a stepping motor operated by operating a toe angle changing switch 35 as a toe angle changing operation tool provided on the operation panel 18a. The rotational position of the meshing right gear 29R is also changed.

That is, when the toe angle change switch 35 is operated to the standard position, as shown in FIG. 2 and FIG. 27, the toe angle of the left and right front wheels 7, 7 is 0 degrees, and the left and right front wheels 7, 7 are in a parallel posture facing straight in the front-rear direction when the fuselage is traveling straight without steering operation of the steering wheel 19. .

When traveling on the road, the toe angle change switch 35 is operated to the standard position. Safe and good driving can be performed at high speed on the road.

When the toe angle change switch 35 is operated to the toe-in position, the stepping motor causes the left gear 29L to rotate in the direction of the arrow (A), and the right gear 29R, which meshes with the left gear 29L, rotates in the direction of the arrow (B). 6, the left and right tie rods 32L, 32R bring the left and right front wheels 7, 7 into the toe-in posture. That is, the left and right front wheels 7, 7 assume a V-shaped posture in a plan view in which the front ends are located inside when the vehicle body is traveling straight without steering operation of the steering wheel 19. FIG.

A limit switch 36 is provided on the pitman arm 27, and the left gear 29L rotates in the direction of the arrow (A) to come into contact with the pin body 33L to detect the maximum toe-in position and stop the stepping motor.

When the left and right front wheels 7, 7 are toe-in, the front wheels 7 on the outer side of the turning are already turned in the turning direction when left and right turning, so the final turning angle becomes large and the turning radius becomes small. Although the front wheel 7 on the inner side of the turn is turned in the opposite direction to the turning direction, since there is a caster angle A, the camber angle changes as it turns in the turning direction, and the contact area with the ground becomes smaller. seldom have a detrimental effect on

During planting work in a paddy field, the toe angle change switch 35 is operated to the toe-in position. The straight line performance during planting work is improved, the seedling rows are straightened, and the seedlings grow well after planting. In addition, since it is possible to turn in a small radius, it is easy to turn on the headland.

Here, the action of the caster angle A of the left and right front wheels 7, 7 will be explained. and the contact area between the ground becomes smaller. As the contact area with the ground becomes smaller, the contact pressure increases and the front wheel 7 bites into the ground better. Furthermore, since the front wheel 7 on the inner side of the turning bites deeply into the ground, the front wheel 7 on the inner side of the turning becomes lower than the front wheel 7 on the outer side, and furthermore, the front wheel 7 on the inner side of the turning cuts into the ground well. Therefore, good turning can be performed.

When the toe angle change switch 35 is operated to the toe-out position, the stepping motor rotates the left gear 29L in the direction of the arrow (c), and the right gear 29R, which meshes with the left gear 29L, rotates in the direction of the arrow (d). 7, and the left and right tie rods 32L, 32R bring the left and right front wheels 7, 7 into a toe-out posture. That is, the left and right front wheels 7, 7 assume an upside-down V-shaped posture in a plan view in which the front ends are positioned on the outer side when the vehicle body is traveling straight without steering operation of the steering wheel 19. FIG.

A limit switch 37 is provided on the pitman arm 27, and the left gear 29L rotates in the direction of the arrow (C) to come into contact with the pin body 33L to detect the maximum toe-out position and stop the stepping motor.

When the left and right front wheels 7, 7 are toeed out, the front wheel 7 on the outer side of the turning is already turned in the opposite direction to the turning direction when turning left and right, so the final turning angle becomes small and the turning radius becomes large. Become. Although the front wheel 7 on the inner side of the turn is turned in the opposite direction to the turning direction, since there is a caster angle A, the camber angle changes as it turns in the turning direction, and the contact area with the ground becomes smaller. seldom have a detrimental effect on

The toe angle change switch 35 is operated to the toe-out position during the planting work in the soft paddy field. Appropriate turning can be performed without damaging the plow bed on the headlands.

Operation rods 38L and 38R are connected to the left and right rear ends of the pivot shaft 28 of the pitman arm 27 for disengaging the side clutches on the inner sides of the turning of the left and right rear wheels 8,8.

Also, when the riding-type rice transplanter 1 with a fertilizing device is produced in a factory, even if the toe angle change switch 35 is operated to the standard position due to processing dimensional errors and assembly errors in each part such as the left and right tie rods 32L and 32R, the handle 19 will not be changed. When the left and right front wheels 7, 7 are not aligned in the front-rear direction when the aircraft is traveling straight without steering operation, a toe angle correction switch is provided in the front cover 18, and the stepping motor is operated by the toe angle correction switch. When operated, the left gear 29L is slightly rotated in the direction of the arrow (A) or (C), and the toe angle change switch 35 is moved to the standard position so that the left and right front wheels 7, 7 are in a parallel posture facing straight in the front-rear direction. can be corrected.

In short, the toe angle change switch 35 is operated to rotate the left and right gears 29L and 29R by means of a stepping motor to change the connection positions of the left and right tie rods 32L and 32R that connect the pitman arm 27 and the left and right front wheels 7 and 7, thereby changing the left and right front wheels. Since the toe angles of 7 and 7 are changed, the toe angles can be easily changed even during running.

<Seedling planting part 4>
The seedling planting part 4 is composed of 6 rows of planting, and a transmission case 40 which also serves as a frame, reciprocates left and right on which the mat seedlings are placed to supply the seedlings one by one to the seedling extraction opening 41a of each row, and also supplies one row of the seedlings. A seedling platform 41 for transferring seedlings downward by a seedling feeding belt for supplying all the seedlings to each seedling outlet 41a, and a seedling planting device 42 for planting the seedlings supplied to the seedling outlet 41a in a field are provided.

In the lower part of the seedling planting part 4, a center leveling float 43 is provided in the center, and side leveling floats 44, 44 are provided on both left and right sides thereof. When the machine body is advanced with these leveling floats 43, 44, and 44 in contact with the muddy surface of the field, the leveling floats 43, 44, and 44 slide while leveling the muddy surface, and the seedling planting device is placed on the leveled ground. Seedlings are planted by 42 . Each of the leveling floats 43, 44, 44 is rotatably mounted so that the front end side moves up and down according to the unevenness of the surface soil surface of the field. Detected by a control sensor (not shown), the seedling planting depth is always kept constant by switching the hydraulic valve for controlling the lifting hydraulic cylinder 26 according to the detection result to move the seedling planting unit 4 up and down. maintain.

A ground leveling rotor 6 for leveling the mud surface prior to the ground leveling floats 43 , 44 , 44 is provided in the front part of the seedling planting part 4 .

<Fertilizer 5>
The fertilizing device 5 feeds out the granular fertilizer stored in the fertilizer hopper 50 by a fixed amount by the feeding part 51, and fertilizing guides 53 attached to the left and right sides of each of the ground leveling floats 43, 44, 44 by the fertilizing hoses 52. The fertilizing guide 53 guides the fertilizing ditch 54 to the front side of the fertilizing guide 53 and drops it into the fertilizing structure formed in the vicinity of the side of the seedling planting row. Air generated by a blower driven by an electric blower motor is blown into the fertilizing hose 52 via an air chamber 55 elongated in the left-right direction, and the fertilizer in the fertilizing hose 52 is forcibly transported by air pressure. ing.

<Another embodiment>
(1) In the above embodiment, the toe angle change switch 35 is used to manually change the left and right front wheels 7, 7 to standard, toe-in, and toe-out. The toe angles of the front wheels 7, 7 may be changed.

That is, when turning, the rear wheel 8 on the inside of the turn is disengaged from the side clutch and becomes an idle wheel, so that it rolls on the field without slipping. slip. Therefore, a left and right rotation speed detection device is provided on the left and right rear wheel axles 13, 13 of the left and right rear wheels 8, 8, and the slip rate is calculated by detecting the rotation speed of the rear wheel 8 on the outside of the turn relative to the rotation speed of the rear wheel 8 on the inside of the turn. can be calculated.

When the slip ratio is greater than the standard value, the aircraft is turning farther than the standard turning radius, so the stepping motor is operated to toe-in the left and right front wheels 7, 7 to enable turning in a small turn. to make the turning radius appropriate for good turning.

Conversely, when the slip ratio is smaller than the standard value, the aircraft is turning less than the standard turning radius, so the stepping motor is operated to toe out the left and right front wheels 7, 7, and a large turning is possible. Then, the turning radius is made appropriate to make a state in which good turning can be performed.

(2) A sensor is provided to detect that the sub-transmission lever is at the moving speed. The stepping motor is operated to set the left and right front wheels 7, 7 to the standard state (toe angle 0 degree).

Therefore, when the auxiliary transmission lever is set to the moving speed, the left and right front wheels 7, 7 are automatically set to the standard state (toe angle of 0 degrees), so that safe and good running can be performed on the road at high speed, and the left and right front wheels 7, 7, The uneven wear of 7 can also be prevented.

(3) A sensor is provided to detect that the sub-transmission lever is at the planting speed, and when the sub-transmission lever is set to the planting speed in the field, the sensor detects that the sub-transmission speed is at the planting speed, and the stepping motor is operated. The left and right front wheels 7, 7 are toe-in by operating.

(4) The body is provided with a GPS to perform self-sustaining running control, and when the self-sustaining running control is activated, the stepping motor is operated to toe-in the left and right front wheels 7,7.

(5) A configuration is provided in which a GPS is provided in the body to perform self-sustaining running control, and control is performed to change the toe angles of the left and right front wheels 7, 7 according to the slip ratio of (1) above only when the self-sustaining running control is activated.

(6) Automatic turning control at the headland (when the handle 19 is operated to turn the machine body, the seedling planting unit 4 is automatically turned off to rise, the turning angle α is detected by the machine direction sensor, and the left and right rear wheels 8 , 8 is detected by the left and right rotation speed detection devices provided on the left and right rear wheel axles 13, 13, and when the vehicle turns at a predetermined angle α1 and travels a predetermined distance L1, the planting portion 4 is lowered, When turning at an angle α2 and traveling a predetermined distance L2, the planting part 4 is driven), if it does not reach the predetermined distance L1 even after turning at a predetermined angle α1, it is determined that the machine body is making a small turn, and stepping. A motor is operated to toe out the left and right front wheels 7, 7 to make a large turn, thereby making the turning radius appropriate.

Further, when the predetermined distance L1 is reached but the predetermined angle α1 is not reached, it is determined that the machine body is making a large turn, and the stepping motor is operated to toe-in the left and right front wheels 7, 7 so that a small turn can be made. Proper turning radius.

7 Left and right front wheels 8 Rear wheels 19 Steering operation device (handle)
27 pitman arm 28 rotating shaft 29L, 29R toe angle changing mechanism (left and right gears)
32L, 32R Left and right tie rods 35 Toe angle change operating tool (toe angle change switch)

Claims (5)

In a traveling vehicle equipped with a rear wheel (8) which is a drive wheel and left and right front wheels (7, 7) steered by a steering operation device (19), the left and right wheels are steered by the steering operation of the steering operation device (19). A pitman arm (27) for steering and rotating the front wheels (7, 7) in the left-right direction via tie rods (32L, 32R) is provided, and the connection position between the tie rods (32L, 32R) and the pitman arm (27) is changed. and a toe angle changing mechanism (29L, 29R) actuated by an actuator for changing the toe angles of the left and right front wheels (7, 7). The toe angle changing mechanism (29L, 29R) is left and right gears (29L, 29R) that mesh with each other provided on the left and right sides of the rotation shaft (28) of the pitman arm (27). One ends of the left and right tie rods (32L, 32R) are connected to each other, and the actuator rotates the left and right gears (29L, 29R) to change the toe angles of the left and right front wheels (7, 7). The running vehicle body described. 3. The traveling vehicle body according to claim 1, wherein the toe angle changing mechanism (29L, 29R) is provided above the pitman arm (27). The traveling vehicle body according to any one of claims 1 to 3, wherein the actuator is operated by operating the toe angle changing operation tool (35) to change the toe angles of the left and right front wheels (7, 7). . A rotation speed detector that detects the rotation speed of the rear wheels (8) calculates the slip ratio, and when the slip ratio is greater than the standard value, the actuator is operated to toe-in the left and right front wheels (7, 7), The traveling vehicle body according to any one of claims 1 to 4, characterized in that when the slip ratio is smaller than a standard value, an actuator is operated to toe out the left and right front wheels (7, 7).

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