JPH10136701A - Small-sized farm work wagon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized farm work wagon capable of simultaneously performing a barley plant treading work and a soil lifting work and improving a steering property and safety by elastically energizing a land roller downwards by an elastically energizing means. SOLUTION: A vertical elevating and lowering mechanism C is provided on the front end of a car body frame 1, the land roller B is attached to the vertical elevating and lowering mechanism C and the land roller B is elastically energized downwards by the elastically energizing means 29. Also, it is preferable that an acceleration lever 17 is provided in an operation part 2, the acceleration lever 17 and the engine of a prime mover part 3 are linked and connected through a linking wire, a low-speed operation mechanism linked and connected to a handle 14 is provided on a position near the middle part of the linking wire, the low-speed operation mechanism is made to act on the linking wire linked with the front wheel steering operation for more than a fixed steering angle of the handle 14 and the engine is rotated at a low speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small agricultural work vehicle.

[0002]

2. Description of the Related Art Conventionally, as one form of a small agricultural work vehicle, a driving unit is provided at a front part of a body frame, a motor unit and a transmission part are provided at a rear part, and left and right front wheels are provided below a front part of the body frame. Attached via the front axle case, the rear left and right rear wheels are attached via the rear axle case below the rear, and the left and right front wheels are interlocked via the front wheel steering mechanism to the steering wheel provided in the driver, while the transmission A side clutch mechanism that interrupts the transmission of power to the left and right rear wheels is provided, and the steering wheel side clutch is disengaged in conjunction with the steering operation of the front wheel by a steering angle greater than a certain steering angle, enabling the vehicle to make small turns. There is a small agricultural work vehicle.

[0003] Such a small agricultural work vehicle is provided with an elevating link mechanism at a rear portion thereof, and various agricultural work machines are connected to the elevating link mechanism so that various agricultural operations can be performed.

[0004]

However, the above-mentioned small agricultural work vehicle still has the following problems.

[0005] That is, various agricultural working machines are connected to the rear part of the machine body via an elevating link mechanism so that various agricultural operations can be performed, but, for example, a wheat stepping operation cannot be performed in a wheat field.

When the steering wheel is steered by a predetermined angle or more to turn the front wheels, the vehicle body can make a small turn. May give a feeling.

[0007]

Therefore, the present invention provides a vertical lifting mechanism at the front end of a vehicle body frame, a pressure-reducing roller is mounted on the vertical lifting mechanism, and the pressure-reducing roller is directed downward by elastic urging means. An object of the present invention is to provide a small agricultural work vehicle characterized by being elastically biased.

Further, according to the present invention, a driving unit is provided at a front portion of a vehicle body frame, a motor unit and a transmission unit are provided at a rear portion, and left and right front wheels are provided below a front portion of the vehicle body frame via a front axle case. At the same time, the rear left and right rear wheels are attached via the rear axle case below the rear,
While the left and right front wheels are interlockedly connected to the steering wheel provided in the driving unit via the front wheel steering mechanism, the transmission unit is provided with a side clutch mechanism for intermittently transmitting power to the left and right rear wheels,
In a small agricultural work vehicle that enables the vehicle body to make small turns by disengaging the side clutch on the steering side in conjunction with the steering operation of the front wheel by a steering wheel at a certain steering angle or more, an accelerator lever is provided in the driving unit. The engine of the prime mover unit is interlocked with the engine via the interlocking wire, and a low-speed operation mechanism that is interlocked with the steering wheel is provided near the middle of the interlocking wire, and is interlocked with the steering operation of the front wheels beyond a certain steering angle of the steering wheel A low-speed operation mechanism acts on the interlocking wire to provide a small agricultural work vehicle configured to rotate the engine at low speed.

Further, according to the present invention, an accelerator lever is provided in a driving unit, and the accelerator lever and an engine of a prime mover unit are interlockingly connected via an interlocking wire. The low-speed operation mechanism interlocks and links the operation mechanism, and the low-speed operation mechanism interlocks with the front wheel steering operation beyond a certain steering angle of the steering wheel in the high-speed operation state of the shift lever provided in the driving section, Another feature is that it is configured to rotate at low speed.

[0010]

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

A shown in FIG. 1 is a small agricultural work vehicle according to the present invention. The small agricultural work vehicle A has a pressure-reducing roller B attached to the front end of a body frame 1 via a vertical lifting mechanism C. An earth-moving machine D is attached to the rear end of the vehicle through a lifting link mechanism E.

As shown in FIGS. 1 and 2, the pressure-reducing roller B is extended in the left-right direction to have a width slightly larger than the left-right width of one ridge U, and is provided in a vertical lifting mechanism C described later. It is mounted on the machine frame 27 via the roller support 21 so as to be rotatable around an axis in the left-right direction. 22 is a rolling spindle,
23 is a left and right auxiliary support, and 24 is a mounting bracket.

As shown in FIGS. 1 to 3, the vertical lifting mechanism C includes a connecting bracket 25 connected to the front end of the vehicle body frame 1.
And a vertical elevator frame fixed to the front end of the connecting bracket 25
26, a slide machine frame 27 slidably mounted in the vertical direction at the front position of the vertical elevator frame 26, elevating means 28 for slidably operating the slide machine frame 27, and the vertical elevator frame 26 and the slide machine. An elastic urging means 29 is provided between the frame 27 and elastically urging the pressure-reducing roller B downward. 27a is a rolling roller, and 42 is a supporting member.

The elevating means 28 has an elevating cylinder 30 erected on a vertical elevating frame 26, a pulley 30b is mounted on the upper end of a piston rod 30a of the elevating cylinder 30, and one end of the pulley 30b is attached to the pulley 30b. The other end of the lifting wire 31 is connected to the slide machine frame 27 via a connection bracket 27b.

In this manner, by moving the piston rod 30a of the lifting cylinder 30 up and down, the sliding machine frame 27 can be moved up and down along the vertical lifting machine frame 26 via the lifting wire 31. The pressure reduction roller B can be moved up and down integrally with the machine frame 27.

The elastic biasing means 29 is provided on a stay 32 which is formed to rise forward and upward from the upper position of the vertical elevator frame 26. It is swingably mounted via a support pin 34, a vertically extending pushing rod 35 is inserted into the cylindrical body 33, and the upper end of the slide machine frame 27 is connected to the lower end of the pushing rod 35 by a connecting bracket.
A plurality of pin insertion holes (not shown) are formed in the upper part of the pressing rod 35 in the up-down direction, and a spring positioning pin 36 is inserted into the pin insertion hole. An upper spring 37 is interposed between the upper end of the cylinder 33 and the upper end of the cylindrical body 33 via spring receivers 38, 38, and a slide positioning body 39 is attached to the lower part of the pressing rod 35 so that the slide position can be adjusted. Body39
A lower spring 40 is interposed between the lower end of the cylindrical body 33 and the lower end of the cylindrical body 33 via spring receivers 41,41.

In this way, the elastic positioning force of the lower spring 40 can be adjusted by adjusting the sliding position of the slide positioning member 39 up and down, and the elastic biasing force of the lower spring 40 is made smaller than the elastic biasing force of the upper spring 37. The lower spring 40 is also set to
The pressure-reducing roller B can be pressed toward the ridge U by an elastic urging force that urges the pressing rod 35 downward against the elastic urging force.

Therefore, the pressing force on the ridge U by the crushing roller B can be arbitrarily set by the slide positioning member 39, and the crushing roller B acts as an optimum crushing force according to the condition of the wheat vegetated on the ridge U. Can be.

As shown in FIGS. 1 and 4, the earthmoving machine D has a transmission shaft case 44 suspended from a transmission gear case 43 and a tilling shaft 45 at the lower end of the transmission shaft case 44 in the left-right direction. , 45, and each tilling shaft 45, 45
6,46 are installed. 47 is a tillage cover, 48 is a scraper, 49 is a tail wheel, and 60 is a transmission case.

The lifting link mechanism E is, as shown in FIG.
A three-point link mechanism is adopted, 61 is a lift arm, 62
Is lower link, 63 is lift link, 64 is top link,
65 is a top link connection body.

As described above, in the small work vehicle A according to the present embodiment, as shown in FIG.
While crushing the wheat vegetated on the top (so-called wheat stepping work), as shown in FIG. I have.

As shown in FIG. 1, the small agricultural work vehicle A has a driving unit 2 at a front portion on a body frame 1 and a motor unit 3 and a transmission unit 4 at a rear portion. Left and right front wheels 5, 5 are provided on the body frame 1 at a position below the driving unit 2.
Are mounted via front axle cases 6 and 6 (see FIG. 5), and left and right rear wheels 7 and 7 are
Are interlockingly connected via rear axle cases 8, 8 (see FIG. 8). Reference numeral 11 denotes a hood that covers the motor unit 3 and the transmission unit 4, and 11 a denotes a fender that covers the rear wheel 7.

As shown in FIG. 1, the driving section 2 has a floor-forming body 12 stretched at the front of the vehicle body frame 1 and
A handle column 13 is erected at the center of the front side of 12, and a handle 14 is attached to the upper end of the handle column 13. The forward / reverse shift lever 16 (FIG. 1) is located on the left side of the handle column 13.
1), and an accelerator bar 17 is provided at an upper position on the right side wall of the handle column 13. A driver's seat 18 is placed at the rear center of the floor forming body 12. Reference numerals 19 denote step portions formed on the front left and right sides of the floor portion forming body 12, respectively.

As shown in FIG. 8, the rear wheels 7, 7 are interlockingly connected to left and right side clutch mechanisms F, F, respectively, provided on the transmission section 4 to connect and receive power transmission from the transmission section 4. It can be cut and the rear wheels 7, 7
It is also possible to brake.

As a steering mechanism, as shown in FIG. 5, a bracket 50 is provided on the front side of the driving section 2 so as to protrude upward between a pair of left and right body frames 1, and the steering shaft is attached to the bracket 50. There are 51 standing. The bracket 50 is formed to have a front-back-to-back-low inclination shape, and the handle column 13 erected on the bracket 50 is also inclined slightly rearward, so that the handlebar connected to the upper end of the steering shaft 51 by the driver is provided. 14 is made easy to operate.

The steering shaft 51 has the steering wheel 14 attached to the upper end thereof, and a front wheel steering mechanism S coupled to the lower end thereof, so that the steering of the steering wheel 14 is transmitted to the front wheels 5 and 5 by the front wheel steering mechanism S. ing.

That is, the front wheel steering mechanism S engages with the drive pinion 74 connected to the lower end of the steering shaft 51 on the lower surface of the bracket 50, as shown in FIGS. And a sector-shaped center gear 75.

The drive pinion 74 and the center gear 75
Is sandwiched between the upper plate 53 and the lower plate 54,
Both plates 53 and 54 are connected to the bracket 50.

The center gear 75 has a base shaft 75a projecting upward and downward from the base end of the center gear 75.
The lower end of the shaft 75a and the boss 71a protruding from the steering arm 71 are connected by spline fitting.

The left and right ends of the steering arm 71 are connected to one ends of left and right drag rods 72, 73, respectively, and the other ends of both rods 72, 73 are connected to the front wheels 5, 5, respectively.
5 is linked.

That is, as shown in FIGS. 5 and 6, a steering arm 71 is connected to the front wheels 5, 5 via left and right drag rods 72, 73, and the steering shaft 51 is connected to the steering arm 71 by the drive shaft. They are interlockingly connected via a pinion 74 and a center gear 75.

Therefore, when the handle 14 is turned, the turning power is changed from the steering shaft 51 to the drive pinion.
74 → center gear 75 → base shaft 75a → boss 71a → steering arm 71, the steering arm 71 swings horizontally at a predetermined steering angle, and the front wheels 5, 5 function as steering wheels.

The above-mentioned left and right side clutch mechanisms F, F are interlockingly connected to the center gear 75 via an interlocking mechanism L.

That is, as shown in FIG. 6, the center gear 75 and the left and right side clutch mechanisms F and F having a braking function are interlockingly connected via an interlocking mechanism L which will be described later. The connection and disconnection operations of the side clutch mechanisms F, F are performed, and a braking force can be applied to the rear wheels 7, 7.

In such a configuration, in this embodiment, FIG.
As shown in FIG. 6, the accelerator lever 17 and the motor 3
Control lever (not shown) provided for the engine 3a
Are interlocked and connected via the interlocking wire 66,
A low-speed operation mechanism 67 connected to the steering wheel 14 is provided at a position near the middle of the steering wheel.
To rotate the engine 3a at low speed.

The accelerator lever 17 is, as shown in FIG.
A lever stay 68 protrudes from the upper part of the steering shaft 51, a lever support shaft 69 whose axis is oriented in the left-right direction protrudes from the lever stay 68, and a boss provided at the lower end of the accelerator lever 17 on the lever support shaft 69. The arm 17a is pivotally supported so that it can be rotated back and forth. An operating arm 90 is provided to project rearward from the boss 17a.
The tip of a is connected.

Here, the interlocking wire 66 is an outer wire
An inner wire 66a is slidably inserted into the inner wire 66b, and the inner wire 66a is advanced and slid in conjunction with the forward rotation operation of the accelerator lever 17, and the control lever of the engine 3a is accelerated by the engine. While turning to the side
The inner wire 66a is slid backward in conjunction with the backward rotation operation of the accelerator lever 17, so that the control lever of the engine 3a is rotated to the engine deceleration side.
91 is an outer receptacle.

The control lever is constantly urged to rotate toward the engine deceleration side, and is rotated toward the engine deceleration side by the relaxation of the inner wire 66a.

Further, as shown in FIG. 7, a part of the inner wire 66a is exposed at an intermediate portion of the transmission wire 66, and a low-speed operation mechanism 67, which will be described later, acts on the exposed inner wire 66a. . 92 and 93 are outer receptacles.

As shown in FIG. 7, the low-speed operation mechanism 67 is a base shaft of a center gear 75 protruding upward from the bracket 50.
A swing arm 94 is attached to the upper end of the bracket 75a so as to protrude rightward, and a trochanter 94a is attached to the tip of the swing arm 94 so as to be rotatable about an up-down axis, while a rotator 94a is attached to the right rear of the bracket 50. The rear end of the arm with a cam 96 extending in the front-rear direction is pivotally supported by an arm support shaft 97 whose axis is oriented vertically, and the rear end of the arm with the cam 96 and the left end of the bracket 50 are A tension spring 98 is interposed therebetween to urge the arm with cam 96 to rotate to the left (counterclockwise), and to rotate the pulley 96d around the vertical axis at the front of the arm with cam 96. The inner wire 66a is freely attached, and the middle part of the inner wire 66a exposed on the pulley 96d is wound around from the right side.

The oscillating arm 94 oscillates in the front-rear direction in conjunction with the steering of the front wheel by the steering wheel 14. On the left side of the arm with cam 96, a convex cam surface 96a and a convex cam surface 96a are provided. The front and rear concave cam surfaces 96b, 96
The rotator 94a of the oscillating arm 94 is brought into contact with any one of these cam surfaces 96a, 96b, 96c.

In this manner, in the neutral position where the steering wheel 14 is moved straight, the swing arm 94 is moved as shown in FIG.
The trochanter 94a abuts against the convex cam surface 96a of the arm with cam 96, rotates the arm with cam 96 rightward against the elastic biasing force of the tension spring 98, and The inner wire 66a is pressed rightward via the pulley 96c, and is bent in a V-shape to apply tension.

When the steering wheel 14 is steered to the left (right) by a predetermined steering angle or more, the swing arm 94 swings rearward (forward) as shown in FIG.
The rotator 94a of the swing arm 94 is connected to the rear cam surface 96c (the front cam surface).
96b), the arm with cam 96 is rotated leftward by the elastic biasing force of the tension spring 98, so that the tension on the inner wire 66a is released.

As a result, the middle portion of the inner wire 66a is restored to a straight shape, and the control lever constantly biased to the engine deceleration side is rotated to operate the engine.
3a is rotated at low speed.

Therefore, when the steering wheel 14 is turned at a predetermined steering angle or more to perform the turning steering, the vehicle speed is automatically reduced, and the vehicle body turns smoothly.

Next, the left and right side clutch mechanisms F, F and the interlocking mechanism L will be described.

As shown in FIG. 8, the left and right side clutch mechanisms F, F are connected to the left and right traveling axles connected to the transmission unit 4.
83,83.

That is, the base ends of the traveling axles 83, 83 facing each other are formed in a spline shape, and the base ends of the bearings 84, 8
4, and a side clutch gear 85 is loosely fitted to hold the bearing 84.

Left and right sliding collars 86, 86 are spline-fitted to the base ends of the traveling axles 83, 83.
The springs 87,87 by the side clutch gear 85
, So that the clutch is engaged.

As shown in FIG. 6, the sliding collars 86, 86 are operatively connected to left and right clutch arms 79, 79, which are formed in a substantially rectangular shape, via connecting shafts F1, F1. The traveling axles 83, 83 are slidable against the elastic biasing force of the springs 87, 87 so as to be disengaged from the side clutch gear 85 so that the clutch can be disengaged.

At the left and right ends of the left and right sliding collars 86, 86, multi-plate type brakes 88, 88 are provided, respectively. , 8
8.

Therefore, when the side clutch is disengaged, the sliding collar 86 is preferably moved outward.
Further, when moved outward, the sliding collar 86 presses the spring 87 to operate the multi-plate brake 88.

Then, when the sliding collar 86 returns to the original position, the braking by the multi-plate brake 88 is released, and the side clutch is again engaged. In FIG. 8, reference numeral 89 denotes a main transmission gear group.

On the other hand, the interlocking mechanism L is interlocked with the center gear 75 of the front wheel steering mechanism S, and connects the left and right side clutch mechanisms F, F according to the turning angle of the front wheels 5, 5 according to the steering angle. A configuration in which a cutting operation is performed and braking force can be applied to the rear wheels 7, 7, and as shown in FIG. 6, a part thereof substantially overlaps with the front wheel steering mechanism S. It has become.

That is, one end of a buffer rod 76 is rotatably connected to the left side of the boss 71a of the steering arm 71 at a predetermined distance, and the other end of the buffer rod 76 is connected to the left and right clutch arms 79 described above. , 79 are connected to a crank 78 interlockingly connected. Reference numeral 81 denotes a buffer spring provided in the middle of the buffer rod 76.

The crank 78 is pivotally supported at the center by a pivot 78b, and the other end of the buffer rod 76 is connected to the pivot 78.
It is rotatably connected to the right side of b with a certain distance.

Therefore, the steering arm 71 and the crank 78
Boss 71a and crank 78, which are the pivot center of steering arm 71
Are connected by a buffer rod 76 arranged crosswise to an imaginary line connecting the pivot 78b of the steering arm 71b.
And the swing direction of the crank 78 are opposite.

Also, engaging pins 78 are provided at both ends of the crank 78.
The engaging pins 78c, 78c are connected to the left and right side clutch operating rods 80, 80, respectively. 80a, 80a
Are pin engagement portions connected to the base ends of the left and right side clutch operation rods 80, 80, and have long holes 77, 77 formed in the pin engagement portions 80a, 80a, respectively. The engagement pin 78
c and 78c are engaged.

On the other hand, left and right side clutch operating rods 80, 8
0 has a base end connected to the left and right side clutch mechanisms F, F via connection shafts F1, F1.
It is linked to 9,79 tips.

With the above configuration, when the steering wheel 14 is rotated, the steering arm 71 swings horizontally at a predetermined steering angle, and the front wheels 5, 5 can be steered at a predetermined steering angle. Then, in conjunction with the horizontal swing of the steering arm 71, the buffer rod 76 moves forward and backward,
The forward / backward movement of the buffer rod 76 causes the crank 78 to horizontally swing in a direction opposite to the swing direction of the steering arm 71.

The horizontal swing of the crank 78 causes the left and right clutch arms 79, 79 to swing via the left and right side clutch operating rods 80, 80, and the connecting shafts F1, F1 connected to the base ends of the clutch arms 79, 79. Is rotated, and the respective side clutch mechanisms F, F of the rear wheels 7, 7 perform a power disconnection operation.

When the handle 14 is further turned, the swing of the steering arm 71 and the crank 78 increases,
The angle at which the connecting shafts F1, F1 of the left and right side clutch mechanisms F, F rotate also increases, and the left and right side clutch mechanisms F, F
The multi-plate type brakes 88, 88 provided in the brakes are operated to apply a braking force to the rear wheels 7, 7.

For example, when the handle 14 is rotated to the left (counterclockwise), the steering arm 71 swings to the right (clockwise), and the left and right drag rods 72 and 73 respectively move to the traction side and the pushing side. The front wheels 5, 5 are turned to the left (counterclockwise) to enable a left turn, and the left side clutch mechanism F performs a power disconnection operation. , The multiple disc brake 88 of the left side clutch mechanism F is operated, and a braking force is applied to the left rear wheel 7.

At this time, the braking force can be arbitrarily set by a buffer spring 81 provided in the middle of the buffer rod 76, and the transmission section 4 can be prevented from being damaged due to a stroke over of the buffer rod 76 or the like. Can be prevented.

With the above configuration, during normal traveling,
A brake turn can be easily performed only by operating the handle 14, and a safe small turn can be performed without a risk of erroneous operation. In addition, the operation feeling during turning is improved.

FIGS. 9 and 10 show a low-speed operation mechanism 67 according to a second embodiment. The low-speed operation mechanism 67 has the same basic structure as the low-speed operation mechanism 67 according to the first embodiment. However, an inner wire restoring action pin 110 is protruded from the arm 96 with the cam, and the hook 111 is extended backward from the base end of the arm with the cam 96 to be integrally formed. The difference lies in that the operation release means 112 is interlocked and connected. 120 is a sliding pin, 121 is a winding spring, and 122 is a shaft support.

That is, the inner wire restoring pin 110
Is the arm with cam 96 located near the rear side of the pulley 96d.
And the pin 110 and pulley 96d
And a middle part of the inner wire 66a.

In this way, even when the middle portion of the inner wire 66a is plastically deformed, the pin 110 for restoring the inner wire is moved in the middle of the inner wire 66a in conjunction with the rotation of the arm with cam 96 to the left. The portion is pressed to the left to restore it straight and the engine 3a is reliably rotated at low speed.

The low-speed operation releasing means 112 is provided for the low-speed operation mechanism 67.
Body attached to the body frame 1 to cover immediately above
A long hole 114 is formed in the left and right direction in 113, and an adjustment bolt 115 is inserted into the long hole 114, and a left end of a locking pin support 116 extending in the left and right direction is inserted into a lower end of the adjustment bolt 115. Attach the lock pin to the right end of the lock pin support 116.
The locking pin 117 is locked to the hook 111 by vertically suspending the hook 117 downward.

A nut 118 is fixed to the lower surface of the left end of the locking pin support 116, and the lower end of the adjusting bolt 115 is screwed to the nut 118, and the adjusting bolt 115 is tightened. The locking pin support 116 can be fixed to the cover 113 and can be slid left and right along the cover 113.

In this way, the adjusting bolt 115 is
4 and fixed to the cover 113 so that the arm 96 with the cam is pivoted to the right to move it to the middle of the inner wire 66a. Locking can be performed with tension applied.In this case, even when turning the steering wheel by turning the steering wheel 14 to a certain steering angle or more, the vehicle speed is not reduced, and the low-speed operation can be released. I can do it.

Also, by loosening the adjustment bolt 115 and allowing the locking pin support 116 to slide left and right along the cover 113, the lock of the arm with cam 96 can be released. , The low-speed operation by the low-speed operation mechanism 67 is automatically performed.

FIG. 11 shows a low-speed operation mechanism 67 as a third embodiment. The low-speed operation mechanism 67 is provided with a solenoid valve 100 for operating an outer receiving body on the body frame 1. The outer receiving body 93 is linked and connected, and the outer receiving body 93 is connected to the solenoid valve 100.
By allowing the inner wire 66a to move in the extension direction of the inner wire 66a in conjunction with the forward and backward movement of the inner wire 66a, the rear interlocking wire 66 supported by the outer receiving body 93 is bent to make the inner wire 66a in a relaxed state. The control lever, which is rotationally biased toward the engine deceleration side, rotates to operate the engine 3a at low speed.

A high-speed changeover detection switch 102 is arranged at a high-speed changeover position of a speed change lever 101 provided on the left side of the driving section 2, and the steering shaft 51 is used to perform a front wheel steering operation of the steering wheel 14 over a certain steering angle. Switch body 10
5 Install the steering detection switch 103 that detects through
These switches 102 and 103 and the solenoid valve 100 are connected in series in an electric circuit.

In this way, when the handwheel 14 is operated to steer the front wheels beyond a certain steering angle while the shift lever 101 is operated at a high speed, the solenoid valve 100 relaxes the inner wire 66a and the vehicle body The vehicle is automatically decelerated so that the vehicle turns smoothly.

A neutral position detecting switch 104 is disposed at a neutral position of the forward / reverse speed change lever 16 disposed on the left side of the handle column 13, and the neutral position detecting switch 104 is electrically connected to the solenoid valve 100 in series. Connected.

In this way, when the forward / reverse shift lever 16 is shifted to the neutral position, the solenoid valve
100 relaxes the inner wire 66a so that the engine 3a rotates at a low speed.

Therefore, when starting the machine, the engine
Even when the rotation speed of 3a is high, it is possible to safely and smoothly start from a low speed to a high speed.

Further, even when the shift lever 101 is operated to shift to a high speed, the vehicle can be started slowly and the operability is good.

Further, even in a vehicle body with a small front wheel load, the vehicle body does not head up at the time of starting, and can be started smoothly and is safe.

Further, when the forward / reverse shift lever 16 is returned to the neutral position, the rotational speed of the engine 3a is reduced, so that fuel consumption can be reduced.

[0082]

According to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, a vertical elevating mechanism is provided at the front end of the vehicle body frame, and a pressure-reducing roller is mounted on the vertical elevating mechanism, and the pressure-reducing roller is elastically urged downward by elastic urging means. For example, in a wheat field, when performing wheat stepping work, the pressure-suppressing roller is brought into contact with the ridge on which wheat is planted in a pressed state by elastic biasing means, and while the vehicle body is traveling forward, By rolling the pressure-reducing roller on the ridge, the wheat stepping operation can be performed reliably.

According to the second aspect of the present invention, the operating unit is provided with an accelerator lever, and the accelerator lever and the engine of the prime mover unit are interlockingly connected via an interlocking wire. Because the low-speed operation mechanism is interlockingly connected to the steering wheel, and the low-speed operation mechanism acts on the interlocking wire in conjunction with the steering operation of the front wheel at a certain steering angle or more of the steering wheel, so as to rotate the engine at low speed, When the operator inadvertently turns,
The vehicle speed is automatically reduced, the vehicle body can be smoothly turned, and the steering performance can be improved without giving a sense of fear to the operator.

According to the third aspect of the present invention, the operating unit is provided with an accelerator lever, and the accelerator lever and the engine of the prime mover unit are interlockingly connected via the interlocking wire, and the interlocking wire is interlockingly connected to the steering wheel in the middle. The low-speed operation mechanism is interlocked with the low-speed operation mechanism, and the low-speed operation mechanism is interlocked with a front wheel steering operation at a steering angle of a certain steering angle or more in a high-speed operation state of a shift lever provided in a driving unit, via an interlocking wire. Because the engine is configured to rotate at low speed, even when the operator inadvertently turns sharply during high-speed traveling,
The vehicle speed is automatically and surely reduced, so that the vehicle body can be turned smoothly, and the steering performance and safety can be improved without giving the operator a fear.

[Brief description of the drawings]

FIG. 1 is an overall side view of a small agricultural work vehicle according to the present invention.

FIG. 2 is an explanatory front view of the small agricultural work vehicle.

FIG. 3 is a front view of a vertical lifting mechanism.

FIG. 4 is an explanatory rear view of the earthmoving machine.

FIG. 5 is an explanatory side view of a front wheel steering mechanism.

FIG. 6 is an explanatory plan view of a transmission mechanism.

FIG. 7 is an explanatory plan view of a low-speed operation mechanism.

FIG. 8 is an explanatory diagram of a side clutch mechanism.

FIG. 9 is an explanatory plan view of a low-speed operation mechanism as a second embodiment.

FIG. 10 is a side view of the low-speed operation mechanism.

FIG. 11 is an explanatory plan view of a low-speed operation mechanism as a third embodiment.

[Explanation of symbols]

 A small agricultural work vehicle 1 body frame 2 driving unit 3 motor unit 4 mission unit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenshiro Eiyoshi 428 Enami, Okayama-shi, Okayama Pref.

Claims (3)

[Claims] 1. A vertical lifting mechanism at a front end of a body frame (1).
(C), a pressure reduction roller (B) is attached to the vertical lifting mechanism (C), and the pressure reduction roller (B) is elastically urged downward by elastic urging means (29). Small agricultural work vehicle. 2. An operation section (2) is provided at a front portion of a body frame (1), and a motor section (3) and a transmission section (4) are provided at a rear section.
The left and right front wheels are located below the front of the body frame (1).
(5, 5) via the front axle case (6, 6), and the rear left and right rear wheels (7, 7) via the rear axle case (8, 8) below the rear. The left and right front wheels (5, 5) are linked to the steering wheel (14) provided via the front wheel steering mechanism (S), while the transmission (4) transmits power to the left and right rear wheels (7, 7). A side clutch mechanism (F, F) is provided to intermittently engage and disconnect the steering wheel side clutch (F, F) in conjunction with the steering operation of the front wheel at a certain steering angle or more by the steering wheel (14). A small agricultural work vehicle with a small turning capability is provided with an accelerator lever (17) in the driving section (2), and the accelerator lever (17) is linked with the engine (3a) of the prime mover section (3) by a wire.
(66) and a low-speed operation mechanism (6) interlockingly connected to the handle (14) at a position near the middle of the interlocking wire (66).
7), the low-speed operation mechanism (67) interlocks with the interlocking wire (66) in conjunction with the steering operation of the front wheel at a certain steering angle or more of the steering wheel (14).
A small agricultural work vehicle configured to operate the engine (3a) at low speed. 3. An operation unit (2) is provided at a front portion of a body frame (1), and a motor unit (3) and a transmission unit (4) are provided at a rear portion.
The left and right front wheels are located below the front of the body frame (1).
(5, 5) via the front axle case (6, 6), and the rear left and right rear wheels (7, 7) via the rear axle case (8, 8) below the rear. The left and right front wheels (5, 5) are linked to the steering wheel (14) provided via the front wheel steering mechanism (S), while the transmission (4) transmits power to the left and right rear wheels (7, 7). A side clutch mechanism (F, F) is provided to intermittently engage and disconnect the steering wheel side clutch (F, F) in conjunction with the steering operation of the front wheel at a certain steering angle or more by the steering wheel (14). A small agricultural work vehicle with a small turning capability is provided with an accelerator lever (17) in the driving section (2), and the accelerator lever (17) is linked with the engine (3a) of the prime mover section (3) by a wire.
(66) and a low-speed operation mechanism (67) interlockingly connected to the handle (14) in the middle of the interlocking wire (66). Shift lever provided in section (2)
In the high-speed operation state of (101), the engine (3a) is configured to rotate at a low speed via the interlocking wire (66) in conjunction with the front wheel steering operation of the steering wheel (14) at a certain steering angle or more. Features a small agricultural work vehicle.