JP2000247240A - Steering section structure of work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the fixing/releasing actions of a steering wheel at the desired longitudinal position and to operate a shift action tool arranged near a driver's seat without trouble by providing a fixing action tool changing the longitudinal position of the steering wheel near the lower side of the steering wheel. SOLUTION: The rotating action of a steering wheel 6 is transferred to a power steering mechanism 11 via a steering shaft 18, universal joints 22, 24 and a joint 25. Since the lower section of the steering shaft 18 is slidable along the axial direction, the longitudinal positions of the steering wheel 6, the steering shaft 18 and a steering holder 15 can be changed. A ring-like fixing action tool 26 is located near the lower side of the steering wheel 6, and the female screw section 26a of the fixing action tool 26 is meshed with the male screw section 14a of a steering post 14, thereby a driver can easily operate the fixing action tool 26 by extending a hand slightly downward from the steering wheel 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a configuration near a control section of a work vehicle, and more particularly to a configuration near a control handle and a cockpit.

[0002]

2. Description of the Related Art In a working vehicle such as an agricultural tractor or a wheel loader, a steering wheel for steering an aircraft body or a speed change device which is operated artificially by operating a transmission for traveling is provided near a cockpit. Etc. are arranged. In such a work vehicle, there is a configuration in which the front and rear positions of the steering wheel can be changed so that the front and rear positions of the steering wheel can be appropriately set for a driver sitting in a cockpit ( Telescopic function).

[0003]

SUMMARY OF THE INVENTION According to the present invention, when the front and rear positions of the steering wheel are changed, an operator who sits in the cockpit can easily perform the operation of fixing and releasing the steering wheel at a desired front and rear position. It is an object of the present invention to provide a configuration in which the operation of a speed change operation tool or the like disposed near the cockpit can be performed easily and without erroneous operation.

[0004]

[I] According to the features of claims 1 and 2, when the front-rear position of the steering wheel is changed, the fixed operating tool near the lower side of the steering wheel is operated, whereby the steering wheel is operated. Can be fixed and released. Thus, the operator sitting on the cockpit can easily operate the fixed operation tool by slightly extending the hand from the steering handle.

[II] According to the feature of claim 3, similar to the case of claim 1 or 2, the "action" described in the above-mentioned [I] is provided, and in addition to this, the following "action" is provided. It has. According to a third aspect of the present invention, when the fixed operation tool is provided so as to be rotatable around a steering shaft connected to the steering handle near the lower side of the control handle, the fixed operation tool is substantially at the center of the left and right range of the control handle. Thus, the steering wheel is slightly hidden under the center of the steering wheel.

With this arrangement, when the operator holds the left and right sides of the steering wheel and extends the hand from the steering wheel to operate another artificial operating tool, the fixed operating tool becomes an obstacle. It is unlikely that the fixed operation tool will be slightly hidden under the center of the steering handle, so that the fixed operation tool will not visually interfere with the pilot .

[III] According to the feature of claim 4, similar to the case of claim 3, the "action" described in the above [I] and [II] is provided, and in addition, the following "action" is provided. "
It has. According to the feature of claim 4, when the fixed operating tool is rotated around the steering shaft to which the steering handle is connected, the fixed member is pressed by the fixed operating tool, and the steering shaft connected to the steering handle is rotatably supported. The fixing member is pressed against the outer peripheral surface of the supporting member to hold the supporting member (the front and rear positions of the steering handle). As described above, by pressing the fixing member so as to surround the outer peripheral surface of the supporting member, the holding of the supporting member (fixation of the front and rear positions of the steering handle) is reliably performed.

In this case, according to the feature of claim 4, since the outer peripheral surface of the fixing member and the inner peripheral surface of the fixed operating tool are formed as inclined surfaces, the inner peripheral surface of the fixed operating tool is rotated by rotating the fixed operating tool. When the surface presses the outer peripheral surface of the fixed member, the fixed member is pressed by the support member due to the wedge effect of the inclined surface, and the support member (the front and rear positions of the steering handle) is held.

[IV] According to the feature of claim 5, as in any one of claims 1 to 4, the above [I]
To [III], in addition to the following “action”. According to the fifth aspect of the present invention, when the lower part of the steering shaft connected to the steering handle is mounted on the universal joint, the mounting position on the universal joint can be changed along the axis of the steering shaft connected to the steering handle. Thus, a position changing unit for changing the front-back position of the steering handle is configured.

Generally, in a working vehicle, a steering shaft connected to a steering handle is configured to be linked to a steering mechanism via a universal joint, and the steering shaft connected to the steering handle and the universal joint are connected to each other. Often, they are composed of different members. Thus, according to the feature of claim 5, when the lower part of the steering shaft connected to the steering handle is attached to the universal joint, the position changing part for changing the front-rear position of the steering handle only by devising the attachment part is provided. It is possible to obtain a position change part that changes the middle part of the steering shaft connected to the steering handle and makes it expandable and contractable to change the front and rear position of the steering handle. It does not need to be performed.

[V] In a work vehicle, a main transmission operation device which operates a main transmission for traveling and is artificially operated, and an auxiliary vehicle which operates a subtransmission for traveling is artificially operated. Auxiliary speed change operation tool, a lifting / lowering operation tool that is manually operated to raise / lower a working device provided in the body, and a PTO that is to manually transmit power to the work device and to cut off the transmission. Some are equipped with operating tools.

In this case, the sub-transmission is generally operated to select whether to perform work traveling (low speed) or traveling on the road (high speed) at a work place, and the operation frequency of the sub-transmission operation tool is often increased. Is relatively small, whereas the main transmission is often operated to obtain an appropriate traveling speed in accordance with a change in the state in both work traveling on the work site and traveling on the road. The frequency of tool operation is relatively high. In the work traveling in the work place, set the state to transmit power to the work equipment,
When traveling on the road, power is not transmitted to the working device in many cases. Therefore, the frequency of operation of the PTO operating tool is relatively low. Since it is necessary to obtain the position of the device, the operation frequency of the lifting / lowering operation tool is relatively high.

[0013] In the above-mentioned state, according to the feature of claim 6, the main shift operation tool and the elevating operation tool, which are relatively frequently operated, are arranged on the same right or left side with respect to the cockpit. The main shift operation tool and the elevating operation tool can be operated with the same right or left hand for the operator sitting in the cockpit. In this case, if the auxiliary transmission operation device and the PTO operation device, which are relatively infrequently operated, are arranged on the same side of the cockpit as the main transmission operation device and the lifting / lowering operation device, the driver can use the main transmission operation device or the PTO operation device. When trying to operate the lifting device,
In some cases, a situation may occur in which the sub-transmission operation tool or the PTO operation tool is erroneously operated. On the other hand, according to the feature of claim 6, since the auxiliary transmission operation device and the PTO operation device, which are relatively infrequently operated, are arranged on the side opposite to the main transmission operation device and the elevating operation device with respect to the cockpit, When the pilot tries to operate the main shifting operation device or the lifting operation device,
The number of situations in which the auxiliary speed change operation tool or the PTO operation tool is erroneously operated is reduced.

[VI] According to the feature of claim 7, similar to the case of claim 6, the "action" described in the preceding item [V] is provided, and in addition, the following "action" is provided. ing. A main shift operation tool and a lifting / lowering operation tool are arranged on the same side on the right or left side of the cockpit, and a sub speed change operation tool and a PTO operation tool are located on the opposite side of the cockpit from the main shift operation tool and the lifting / lowering operation tool. If, for example, the main shift operation tool and the elevating operation tool are arranged side by side in the lateral direction of the machine, it is possible to arrange the main speed change operation tool and the elevating operation tool in the lateral direction of the machine, Since it is difficult due to the limitation of the width and the like, when the operator tries to operate the main speed change operation tool, a state may occur in which the operator mistakenly operates the elevating operation tool.

According to a seventh aspect of the present invention, the main shift operation device and the elevating operation device are arranged side by side along the longitudinal direction of the fuselage on the same side on the right or left side with respect to the cockpit. On the side opposite to the operation tool and the lifting operation tool,
The sub-shift operation tool and the PTO operation tool are arranged side by side in the longitudinal direction of the aircraft. This makes it possible to set relatively large spaces between the main speed change operation tool and the lifting / lowering operation tool and between the auxiliary speed change operation tool and the PTO operation tool.
The operator can easily recognize the difference between the position of the main speed change operation tool and the position of the elevation operation tool and the difference between the position of the sub speed change operation tool and the PTO operation tool.

[VII] In a work vehicle, generally, a plurality of artificial operation tools are arranged on the side of the cockpit (both right and left, only right or only left). In this case, according to the feature of claim 8, the grip portion of the artificial operation tool farther from the cockpit is set higher than the grip portion of the artificial operation tool closer to the cockpit. As a result, if the pilot sitting on the cockpit reaches out to the side and tries to hold the grip of the artificial manipulation tool far from the cockpit, the grip of the artificial manipulation tool near the cockpit will be Since it is low, it is possible to have the grip portion of the artificial operation tool far from the cockpit without being obstructed by the grip portion of the artificial operation tool near the cockpit.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a body is supported by a pair of left and right front wheels 1 and a pair of left and right rear wheels 2 which can be steered left and right, and an engine 3 is arranged at a front portion of the body. A maneuvering unit 4 is provided at the rear of the body, and a lift arm 5 for operating a working device (not shown) connected to the rear of the body is provided to constitute an agricultural tractor as an example of a work vehicle. Have been.

Next, the structure near the steering wheel 6 for steering the front wheel 1 left and right will be described. 1 and 2
As shown in the figure, the engine 3 is covered with a bonnet 7, a fuel tank 8 is disposed on the rear side of the engine 3, and an instrument panel 9 is disposed on the rear side of the fuel tank 8.
Tachometer (not shown) or fuel gauge (not shown) of engine 3
An instrument section 10 having the same is attached to the instrument panel 9. A hydraulic power steering mechanism 11 that steers the front wheels 1 left and right is disposed below the rear end of the fuel tank 8.

As shown in FIGS. 2 and 3, a support bracket 12 is fixed to an upper portion of the power steering mechanism 11, and a bifurcated support member 13 is swingably supported around a horizontal axis P1 of the support bracket 12. The cylindrical steering post 14 is fixed to the support member 13. The steering post 14 has an opening 9a in the instrument panel 9.
, And a bellows-like boot 19 made of rubber is attached to the opening 9 a of the instrument panel 9 so as to surround the steering post 14.

As shown in FIGS. 3 and 5, a cylindrical steering holder 15 is slidably disposed inside the steering post 14, and a bolt 55 attached to the steering post 14 is inserted into a long hole 15a of the steering holder 15. It is inserted, the steering holder 15 is prevented from rotating with respect to the steering post 14, and the sliding range of the steering holder 15 is determined by the long hole 15a.

As shown in FIG. 3, the lower bearing 16
The steering shaft 18 is rotatably supported by the steering holder 15 by the upper bush 17 and the upper bush 17.
The steering handle 6 is fixed to the upper end of the steering shaft 18. Boss part 22a of universal joint 22
Is rotatably supported by the support member 13 by the holder collar 20 and the bearing 21, and is supported by the clip 23 so as not to fall down. The joint portion of the universal joint 22 is arranged at the position of the horizontal axis P1. I have. Input shaft 11 of power steering mechanism 11
a, a universal joint 24 is attached to the upper and lower universal joints 22, 24.
Are connected by a joint 25.

As shown in FIGS. 3 and 4, a spline portion 18a is formed on the outer surface of the lower portion of the steering shaft 18,
A spline portion 22b is formed on the inner surface of the boss portion 22a of the universal joint 22, the lower portion of the steering shaft 18 is inserted into the boss portion 22a of the universal joint 22, and the steering shaft 18 and the universal joint 22 rotate integrally, In addition, the lower portion of the steering shaft 18 is configured to be slidable along the axis of the steering shaft 18 with respect to the boss portion 22a of the universal joint 22. Thus, the rotation operation of the steering wheel 6 is transmitted to the power steering mechanism 11 via the steering shaft 18, the universal joints 22, 24, and the joint 25, and the front wheels 1 are steered left and right.

As described above, the universal joint 22
The lower portion of the steering shaft 18 with respect to the boss portion 22a of
By being slidable along the axis of the steering shaft 18, the steering handle 6, the steering shaft 18
In addition, the front and rear positions of the steering holder 15 (the bearing 16 and the bush 17) are configured to be freely changeable along the axial direction of the steering shaft 18. The state shown in FIGS. 2 and 3 is a state in which the control handle 6 is depressed most diagonally downward, the state in which the front and rear positions of the control handle 6 are farthest away from the cockpit 28 shown in FIG. 1, and is shown in FIG. The state is a state in which the steering handle 6 is pulled out at the most diagonally upward,
The front and rear positions of the steering handle 6 are closest to the cockpit 28.

As shown in FIGS. 2 and 3, a male screw portion 14a is formed on the outer peripheral surface of the upper portion of the steering post 14, and the female screw portion 26a of the ring-shaped fixing operation tool 26 is connected to the male screw portion of the steering post 14. The fixed shaft 26, the steering holder 15, and the bush 17 pass through the opening of the fixed shaft 26, and the fixed shaft 26 is located near the lower side of the steering handle 6.
A fixing member 27 is attached to an upper end of the steering holder 15, and the fixing member 27 is a ring shape having an outer peripheral surface 27a formed in a conical inclined surface, and a part of the outer peripheral portion of the fixing member 27 is cut out. The outer diameter of the fixing member 27 can be reduced from the outside. The inner peripheral surface 26 b of the fixed operating tool 26 is formed as a conical inclined surface, and the inner peripheral surface 26 b of the fixed operating tool 26 is in contact with the outer peripheral surface 27 a of the fixing member 27.

Thus, the fixed operating tool 26 is rotated around the steering post 14 (around the steering shaft 18) (for example, clockwise), and the fixed operating tool 26 is actuated by the male screw portion 14a and the female screw portion 26a. 26 is moved below the steering post 14, the fixed operating tool 2
6 is pressed against the outer peripheral surface 27a of the fixing member 27, and the outer diameter of the fixing member 27 is reduced.
Is pressed against the outer peripheral surface of the steering holder 15, and the steering member 15 is frictionally held by the fixing member 27. As a result, the steering handle 6, the steering shaft 18
In addition, the front and rear positions of the steering holder 15 (the bearing 16 and the bush 17) can be fixed. In this case, even if the bush 17 is configured to have a sufficient strength and the fixing member 27 is pressed against the outer peripheral surface of the steering holder 15 and the steering holder 15 is frictionally held by the fixing member 27 as described above, the steering handle 6 and the steering shaft 18 can be rotated without any trouble.

The fixed operating tool 26 is connected to the steering post 14
The fixed operation tool 26 is rotated around (around the steering shaft 18) in the opposite direction (for example, counterclockwise) to move the fixed operation tool 26 above the steering post 14 by the action of the male screw portion 14a and the female screw portion 26a. Then, the pressing of the inner peripheral surface 26b of the fixing operation tool 26 on the outer peripheral surface 27a of the fixing member 27 is weakened, the outer diameter of the fixing member 27 increases, and the frictional holding of the steering holder 15 by the fixing member 27 is released. . Thereby, the steering handle 6, the steering shaft 18, and the steering holder 15 (bearing 16)
The front and rear positions of the bush 17) are
Of the steering holder 15 along the axial direction of the
It can be changed steplessly within the range of a.

As shown in FIGS. 2 and 3, the support member 13 is swingably supported around the horizontal axis P1 of the support bracket 12, and the joint portion of the universal joint 22 is arranged at the position of the horizontal axis P1. With this configuration, the vertical angle of the steering handle 6 and the steering shaft 18 can be changed. A fixed lever 29 is swingably supported around a support pin 12 a fixed to the support bracket 12, and projects rearward from a rear panel 30. A balance arm 32 is swingably supported around a support pin 31a of a support plate 31 fixed to the support bracket 12, and a locking member 3 having a plurality of gear tooth-shaped locking portions 33a.
3 is fixed to the steering post 14, and the engaging portion 32 a of the balance arm 32 is
It is configured to engage with. The fixed lever 29 and the balance arm 32 are connected by a link 34, and a spring 35 for urging the fixed lever 29 to a fixed position below is attached to the link 34.

The state shown by the solid line in FIG. 2 and the state shown in FIG. 3 is a state in which the fixing lever 29 is held at a fixing position by the spring 35, and the engaging portion 32a of the balance arm 32 is
3 is engaged with one of the locking portions 33a, and the vertical angle of the steering handle 6 and the steering shaft 18 is fixed. When the fixing lever 29 is operated from the state shown by the solid line in FIG. 2 to the release position shown by the two-dot chain line in FIG. 2 against the spring 35, the balance arm 32 swings clockwise in FIG.
The engaging portion 32a of the balance arm 32 separates downward from the locking portion 33a of the locking member 33. As a result, the steering handle 6
Then, the vertical angle of the steering shaft 18 can be changed. Thereafter, the fixing lever 29 is operated to the fixing position shown by the solid line in FIG.
Is engaged with the locking portion 33a of the locking member 33, thereby fixing the vertical angle of the steering handle 6 and the steering shaft 18 at a desired vertical angle.

Next, the structure near the cockpit 28 will be described. In this agricultural tractor, a traveling main transmission (not shown) capable of changing the speed to three forward speeds and one reverse speed is provided.
An auxiliary transmission (not shown) for traveling capable of changing gears to four speeds, a four-wheel drive state for transmitting power to the front wheels 1 and the rear wheels 2, and the front wheels 1
A switching mechanism (not shown) operable in a two-wheel drive state for transmitting power only to the rear wheel 2 without transmitting power to the rear wheel 2 is provided, and the lift arm 5 (see FIG. 1) is moved to a desired vertical angle. Is provided with a position elevating mechanism (not shown) for performing an elevating operation. As shown in FIG. 1, a rear PTO shaft 3 for transmitting power to a working device (not shown) connected to a rear portion of the body.
6. A mid-PTO shaft 37 for transmitting power to a working device (not shown) connected between the front wheel 1 and the rear wheel 2 is provided.

As shown in FIGS. 1 and 6, in the control section 4, fenders 38 and 39 for covering the upper side of the rear wheel 2 are disposed on the right and left sides of the cockpit 28, and the main transmission for operating the main transmission. A lever 40 is disposed at the front of the right fender 38. An elevating lever 41 for operating the position elevating mechanism to elevate and lower the lift arm 5 to a desired vertical angle, and a switching lever 42 for operating the switching mechanism between a four-wheel drive state and a two-wheel drive state are provided at the rear of the right fender 38. The auxiliary handle 43 is fixed to the outer end of the right fender 38. An arched ropes frame 56 is arranged behind the cockpit 28.

As shown in FIG. 6, a sub-transmission lever 43 for operating the sub-transmission is disposed at the front of the left fender 39 to transmit power to the rear PTO shaft 36 and to cut off transmission. Mid PTO for transmitting and disconnecting power to lever 44 and mid PTO shaft 37
The lever 45 is arranged side by side at the rear of the left fender 39, and the auxiliary handle 43 is fixed to the outer end of the left fender 39. An expandable seat belt 46 is provided on the left side of the cockpit 28, and the cockpit 2
On the right side of 8, a fixing portion 54 for connecting a metal fitting at the tip of the seat belt 46 is arranged.

As shown in FIGS. 1 and 6, on the floor 47 of the control unit 4, a right side brake pedal 48 capable of independently braking the right rear wheel 2, and a left side brake capable of independently braking the left rear wheel 2. A brake pedal 49 and an accelerator pedal 50 of the engine 3 are disposed on the right side of the floor 47, and a clutch pedal 51 for transmitting and disconnecting a main clutch (not shown) is disposed on the left side of the floor 47. I have.

[First Embodiment of the Invention] FIGS. 1 and 6
The agricultural tractor shown in FIG. 1 includes a main transmission (not shown) for traveling that can be shifted in three stages of forward movement and one stage of reverse movement. There is an agricultural tractor provided with a hydrostatic continuously variable transmission (not shown) capable of continuously changing the speed.

In this case, as shown in FIG. 7, the main shift lever 40 (see FIG. 6) is not provided, and the lifting lever 41, the switching lever 42 and the auxiliary handle 43 are attached to the right fender 38 as in FIG. Are located. Sub speed lever 43,
The rear PTO lever 44, the mid PTO lever 45, and the auxiliary handle portion 43 are disposed on the left fender 39 similarly to FIG. 6, and a retractable seat belt 46 is provided on the left side of the cockpit 28, and the right side of the cockpit 28. The fixing portion 54 is arranged at the bottom.

As shown in FIG. 7, a right side brake pedal 48, a left side brake pedal 49, and a clutch pedal 51 are arranged on the floor 47 of the control section 4, as in FIG. A forward pedal 52 for operating the hydrostatic stepless transmission on the high speed side of forward movement and a reverse pedal 53 for operating the high speed side of reverse movement are arranged on the right side of the floor 47.

[Second Alternative Embodiment of the Invention] As described in the first alternative embodiment of the present invention, a main transmission device for traveling that can be freely shifted to three forward speeds and one reverse speed is used. In the case of an agricultural tractor provided with a hydrostatic continuously variable transmission (not shown) capable of continuously changing the speed from the neutral position to the forward side and the reverse side, the configuration may be as shown in FIG. As shown in FIG. 8, when the lifting lever 41 and the switching lever 42 are disposed on the right fender 38, the lifting lever 41 is disposed on the outer side of the fuselage, the switching lever 42 is disposed on the cockpit 28, and the cockpit is provided. The grip portion 42 of the switching lever 42 on the side closer to 28
The grip portion 41a of the lift lever 41 farther from the cockpit 28 than "a" is set at a higher position.

Sub transmission lever 43, rear PTO lever 44
When the mid PTO lever 45 is arranged on the left fender 39, the rear PTO lever 44 is arranged at the center,
The auxiliary transmission lever 43 is arranged on the outside of the fuselage
The O lever 45 is disposed on the cockpit 28 side. In this case, the grip portion 45a of the mid PTO lever 45 closer to the cockpit 28 with respect to the grip portion 44a of the rear PTO lever 44.
a is set at a low position, and the grip portion 43a of the auxiliary transmission lever 43 farther from the cockpit 28 is set at a higher position than the grip portion 44a of the rear PTO lever 44.

Third Embodiment of the Invention FIGS. 6, 7, and 8
In the configuration shown in FIG.
2 (main transmission lever 40) may be arranged on the left fender 39, and the sub transmission lever 43, the rear PTO lever 44 and the mid PTO lever 45 may be arranged on the right fender 38.

In the configuration shown in FIG.
0 to the right fender 38 (or the left fender 3
9) Arranged at the rear part, the lifting lever 41 and the switching lever 4
2 to the right fender 38 (or the left fender 3
It may be arranged at the front of 9). Similarly, in the configuration shown in FIG. 6, the auxiliary transmission lever 43 is disposed at the rear of the left fender 39 (or the right fender 38), and the rear PTO
The lever 44 and the mid PTO lever 45 may be arranged at the front of the left fender 39 (or the right fender 38).

In the configuration shown in FIG.
Is arranged on the cockpit 28 side, and the switching lever 42 is arranged laterally outside the fuselage, and the grip of the switching lever 42 farther from the cockpit 28 than the grip portion 41a of the lift lever 41 closer to the cockpit 28 is gripped. The portion 42a may be set at a higher position. Similarly, in the configuration shown in FIG.
Contrary to 4, the auxiliary transmission lever 43 may be disposed on the cockpit 28 side, and the mid-PTO lever 45 may be disposed on the lateral outside of the body. In this case, the grip portion 44a of the rear PTO lever 44
In contrast, the grip portion 43a of the auxiliary transmission lever 43 closer to the cockpit 28 is set to a lower position, and the rear PTO lever 44
The grip portion 45a of the mid PTO lever 45 farther from the cockpit 28 may be set at a higher position than the grip portion 44a.

In the configuration shown in FIG. 6, the grip portion 41 of the lift lever 41 and the switching lever 42 on the side close to the cockpit 28.
The grip portion 40a of the main transmission lever 40 farther from the cockpit 28 than a and 42a may be set at a higher position. Similarly, in the configuration shown in FIG. 6, the grip portion 43a of the auxiliary transmission lever 43 farther from the cockpit 28 than the grip portions 44a, 45a of the rear PTO lever 44 and the mid PTO lever 45 closer to the cockpit 28. It may be set at a higher position. Instead of the hydraulic power steering mechanism, an electric power steering mechanism using an electric motor may be used, or a steering mechanism without a power assist function may be used. The present invention enables not only a farm tractor that steers the pair of left and right front wheels 1 but also a front body provided with the front wheels 1 and a rear body provided with the rear wheels to be swingable (bendable) around a vertical axis. Work vehicles such as a wheel loader and a pair of left and right crawler traveling devices that are configured to perform a steering operation in connection with each other, and perform a steering operation of the aircraft by giving a driving speed to the left and right crawler traveling devices Applicable.

[0042]

According to the first and second aspects of the present invention, when the front / rear position of the steering wheel is changed in the operating part structure of the work vehicle, the fixed operating tool for fixing and releasing the front / back position of the steering wheel is provided. By positioning the control handle near the lower side, the operator can easily operate the fixed operation tool by extending his / her hand slightly downward from the control handle. Operability was improved.

According to the feature of claim 3, claim 1 or 2
"Effects of the Invention" of Claim 1 or 2 as in the case of
In addition to this “effect of the invention”, the following “effect of the invention” is provided. According to the feature of the third aspect, the fixed operating tool is rotatably provided near the lower side of the steering handle around the steering shaft connected to the steering handle, and the fixed operating tool is provided substantially at the center of the left and right range of the steering handle. However, since it is slightly hidden under the center of the steering handle, the fixed operating tool does not hinder the operation of other human-operated operating tools. The visual obstruction was reduced, and the operability and visibility of the artificial operation tool other than the fixed operation tool could be improved.

According to the feature of the fourth aspect, the "effect of the invention" of the third aspect is provided similarly to the case of the third aspect, and in addition to the "effect of the invention", the following "invention" is provided. Of the effect. According to a fourth aspect of the present invention, in a support member rotatably supporting a steering shaft connected to a steering handle, a fixed member is pressed by a fixed member so as to surround an outer peripheral surface of the support member, and the fixed member is formed by a wedge effect by an inclined surface. Is pressed by the support member, the holding of the support member (fixation of the front and rear positions of the steering handle) is reliably performed, and the reliability of the structure for fixing the front and rear positions of the steering handle can be improved. Was.

According to the feature of claim 5, the "effect of the invention" of the claims 1 to 4 is provided similarly to any one of the claims 1 to 4, and the "effect of the invention" is included in the "effect of the invention". In addition, it has the following "effects of the invention". According to the feature of claim 5, when the lower part of the steering shaft connected to the steering handle is attached to the universal joint, it is possible to obtain a position changing part for changing the front-back position of the steering handle only by devising the attachment part. This is advantageous in terms of simplification of the structure.

According to a sixth aspect of the present invention, the main shift operation device and the elevating operation device, which are relatively frequently operated in the operation section structure of the work vehicle, are arranged on the same right or left side with respect to the cockpit. By arranging the infrequently operated auxiliary shift operation tool and PTO operation tool on the opposite side of the cockpit from the main shift operation tool and the elevating operation tool, erroneous operation can be prevented beforehand. Became.

According to the feature of claim 7, the "effect of the invention" of the above-described claim 6 is provided similarly to the case of the claim 6, and in addition to the "effect of the invention", the following "invention" is provided. Of the effect. According to the feature of claim 7, by arranging the main speed change operation tool and the lifting / lowering operation tool, the sub speed change operation tool and the PTO operation tool along the longitudinal direction of the body, the position of the main speed change operation tool and the elevation operation tool is adjusted. The difference makes it easier for the operator to clearly recognize the difference between the position of the sub-shift operation tool and the position of the PTO operation tool, thereby preventing an erroneous operation from occurring.

According to the eighth aspect of the present invention, the grip portion of the artificial operation device far from the cockpit is set higher than the grip portion of the artificial operation device near the cockpit in the operation portion structure of the work vehicle. By doing so, it is possible to have the grip of the artificial operation tool far from the cockpit without being disturbed by the grip of the artificial operation tool near the cockpit, and the operability of the artificial operation tool Could be improved.

[Brief description of the drawings]

FIG. 1 is an overall side view of an agricultural tractor.

FIG. 2 is a longitudinal side view of the vicinity of a steering handle.

FIG. 3 is a longitudinal rear view of the vicinity of the steering handle showing a state in which the steering handle is pushed down most diagonally.

FIG. 4 is a longitudinal rear view of the vicinity of the steering handle, showing a state in which the steering handle is pulled out at the most obliquely upward;

FIG. 5 is a cross-sectional plan view near a bolt in the steering post.

FIG. 6 is a perspective view of the control unit as viewed obliquely from above and behind.

FIG. 7 is a perspective view of the control section viewed from obliquely rearward and upper direction in the first alternative embodiment of the invention;

FIG. 8 is a longitudinal rear view of the vicinity of a control section according to a second modification of the present invention.

DESCRIPTION OF THE SYMBOLS 6 Steering handle 11 Steering mechanism 15 Support member 18 Steering shaft 22 Universal joint 26 Fixed operating tool 26b Inner peripheral surface of fixed operating tool 27 Fixed member 27a Outer peripheral surface of fixed member 28 Pilot seat 40 Main shifting operating tool, Artificial operation tool 41 Lifting operation tool, Artificial operation tool 42 Artificial operation tool 43 Auxiliary speed change operation tool, Artificial operation tool 44, 45 PTO operation tool, Artificial operation tool 40a, 41a, 42a, 43a, 44a, 45a Gripping of Artificial operation tool Department

Claims (8)

[Claims] A steering mechanism for performing a steering operation of the fuselage; and a steering handle that is manually operated. The steering mechanism and the steering handle are interlocked and connected via a steering shaft. A fixed operation tool which is provided with a position changing portion capable of changing the front-rear position of the steering handle along the axial direction of the connected steering shaft, and which fixes and releases the front-rear position of the steering handle and is manually operated. The operation part structure of the working vehicle provided near the lower side of the operation handle. 2. A steering mechanism for performing a steering operation of an airframe, and a steering handle that is artificially operated. The steering mechanism and the steering handle are interlocked and connected via a steering shaft. A position changing unit that can change the front-rear position of the steering handle along the axis of the connected steering shaft, and an angle changing unit that can change the vertical angle of the steering handle and the steering shaft connected to the steering handle. And a fixed operation tool which is manually operated to fix and release the front and rear positions of the steering handle and is provided near a lower side of the steering handle. 3. The operating section structure of a working vehicle according to claim 1, wherein the fixed operating tool is rotatably operated near a lower side of the operating handle around a steering shaft connected to the operating handle. . 4. A fixing member for fixing a front-rear position of the steering handle by pressing an outer peripheral surface of a support member rotatably supporting a steering shaft connected to the steering handle, the outer peripheral surface of the fixing member, The inner peripheral surface of the fixed operating tool is formed as an inclined surface, and by rotating the fixed operating tool, the outer peripheral surface of the fixing member is pressed by the inner peripheral surface of the fixed operating tool, and The operating portion structure of a working vehicle according to claim 3, wherein the fixing member presses an outer peripheral surface to fix a front-rear position of the operating handle. 5. A universal joint is attached to a lower part of a steering shaft connected to the steering handle, and the universal joint and the steering mechanism are configured to be linked to each other. The position change unit is configured to change a mounting position on the universal joint along an axial direction of a steering shaft connected to the control handle, thereby changing a front-rear position of the control handle. The operating part structure of the working vehicle according to any one of claims 1 to 4. 6. A main shift operation device which is operated by manipulating a main transmission device for traveling and is manually operated on one side of the cockpit and a manipulator which is operated by raising and lowering a working device provided on an airframe. A vertically operated operating device which is operated by a driver, and which is operated on the other side of the cockpit by operating the auxiliary transmission device for traveling. A control section structure of a working vehicle in which a PTO operation tool for transmitting and stopping power transmission and operated artificially is arranged. 7. The main shift operation tool and the lifting / lowering operation tool are arranged side by side in the longitudinal direction of the fuselage on one of the left and right sides of the cockpit, and the sub speed change operation tool and the PTO are arranged on the left and right sides of the cockpit. The operating part structure of a working vehicle according to claim 6, wherein the operating tool and the operating tool are arranged side by side in the longitudinal direction of the vehicle. 8. A plurality of artificially operated devices that are artificially operated are arranged on a lateral side of a cockpit, and a grip portion of the artificially operated device that is closer to the cockpit among the plurality of artificially operated devices. Also, the control section structure of the working vehicle in which the grip portion of the artificial operation tool far from the cockpit is set high.