JPH0238128Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is applicable to work vehicles where the operator often performs work while looking back, such as when plowing with a tractor, or the seat of the vehicle body. Work vehicles that are configured so that the operator's seating direction faces rearward due to the replacement of The present invention relates to a speed change operation device for a work vehicle, which is configured to easily change the vehicle speed even when the vehicle is directed toward a direction other than the rear or front of the vehicle body.

[Prior art]

Conventionally, the gear change operation of a work vehicle was performed using a lever or pedal located in front of or on the side of the driver's seat.Usually, the lever or pedal was installed in only one place, and the operator was seated facing forward. It is located at the position where operability is most improved when

[Problem that the invention attempts to solve]

However, for example, in the case of agricultural tractors, the operator frequently looks back at the rear of the vehicle to check the working status of the work equipment connected to the plow or the like connected to the rear while driving, and the traction load increases or decreases during the operation. Depending on the situation, it may be necessary to change the traveling speed of the vehicle, and for example, during excavation work at a excavation site, the swivel platform may remain sideways with respect to the traveling vehicle, and the work position may need to be changed. When traveling, the aircraft is operated with the body turned sideways relative to the control section for traveling operations. In these cases, it is difficult for the driver who is looking back to operate the gear shift control lever, etc., and also because the operator has to turn his/her eyes toward the front of the vehicle to confirm the operation. There is also the problem that confirmation of the work status and confirmation of avoidance of contact with other objects of the backhoe device tend to be insufficient.

In addition, in agricultural tractors that are configured so that the seat of the vehicle body is replaced so that the operator is seated toward the rear of the vehicle body, the driver may be seated facing the rear of the vehicle body. In order to obtain an operation structure that allows the gear change operation to be performed from the front of the vehicle, there is a problem in that the structure tends to be complicated.

The present invention was developed in view of the above-mentioned circumstances, and even when the driver directs his/her line of sight to a direction other than the front of the vehicle body, such as the rear or side of the vehicle body, the operator's line of sight is directed toward the front of the vehicle body, and the operator is in operation. It is an object of the present invention to provide a speed change operating device that can be operated in a comfortable posture without having to confirm the above.

[Means for solving problems]

The characteristics of the present invention are that the driving transmission mechanism is configured to be controlled in multiple stages by an electric actuator whose operation is controlled by a switch selection operation of a transmission operation unit consisting of a group of switches; The gear shift operating section is connected to a control device located on the vehicle body via a flexible electrical cord, and the shift operating section is detachably attached to a position near the driver's seat. , its action and effects are as follows.

[Effect]

In other words, as mentioned above, since the traveling speed can be changed via the electric actuator by operating the switch, the switch group can be changed by simply setting the length of the electrical cords that connect the control device for operating the electric actuator and the switch group. can be installed anywhere on the vehicle body, and the structure for installation is extremely simple.

In addition, as mentioned above, the switch-type gear shift operation part is removably attached to a position near the driver's seat, so if the shift operation part is removed and held in the hand, the operator can move around the rear of the vehicle or Even when the user is looking in a direction other than the front, such as sideways, the gear change operation can be performed and the operation can be confirmed without taking the user's line of sight too far or changing the posture.

Furthermore, even if the seat of the vehicle is replaced so that the driver's seating direction faces toward the rear of the vehicle, the gear shift operation section should be located in front of the driver for the reasons mentioned above. Can be done.

[Effect of idea]

Therefore, with a relatively simple structure, a switch-type gear shift operation unit connected to an electric cord and capable of changing the vehicle speed is removably installed near the driver's seat, and this shift operation unit can be easily attached to the rear of the vehicle body or Since it can be operated from any position such as the side, the driver can easily shift gears even when the driver is pointing in a direction other than the front of the vehicle, such as the rear or side of the vehicle. without taking your gaze away from the
In addition, there is provided a gear shift operating device that can be easily changed without changing the posture, can be done easily by simply operating a switch, and can economically change the vehicle speed by only providing one gear shift operating section. It came to this.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Fig. 1, an engine E is mounted on the front part of the aircraft, which is provided with steering drive wheels 5 at the front and drive wheels 4 at the rear. The agricultural tractor is constructed by sequentially connecting the case M and a control section D provided with a meter panel 16, a control handle 17, a seat 18, etc. in the center of the machine body.

The transmission case M is constructed so that its traveling speed change operation is performed by hydraulic pressure, which will be described in detail below.

As shown in FIGS. 2 and 3, a synchronized mesh main gear transmission H 1 that can freely switch between four stages is provided between the input shaft 1 and the first driving transmission shaft 2 which are interlocked and connected to the engine _E. A synchronized mesh forward/reverse gear transmission H includes a friction plate type transmission clutch C between the first transmission shaft 2 and the second traveling transmission shaft 3, and changes the output of the second transmission shaft 3 in forward and reverse directions. ₂ , a synchronized mesh type first auxiliary gear transmission _H3 that can freely switch the output from it into two high and low stages; and a second auxiliary gear transmission that can freely switch the output from it between two high and low stages.
_H4 each provided, and the second auxiliary gear transmission
The output of H ₄ is transmitted to the differential mechanism 4A for the rear wheels 4 and the differential mechanism 5A for the front wheels 5.

A synchromesh type gear transmission 7 is provided which changes the power of the input shaft 1 into four stages and transmits it to the power extraction transmission shaft 6, and a friction plate type transmission is provided between the transmission shaft 6 and the power extraction shaft 8. A clutch 9 is provided so that the speed of the power take-off shaft 8 can be changed.

Next, the speed change operation structure for the driving transmission system will be described in detail with reference to FIGS. 3 and 4.

That is, the main gear transmission H ₁ includes a hydraulic cylinder 10 for operating a gear shifter that is selectively operated.
A and 10B are attached, and hydraulic cylinders 11 and 12 for operating the transmission shifter are attached to the forward and reverse gear transmission H ₂ and the first auxiliary gear transmission H ₃ , respectively.
one of the transmission clutches C is attached, and the transmission clutch C
A hydraulic cylinder 13 for entering operation is attached to the holder.

The main gear shifting hydraulic cylinders 10A, 10B
and a main control valve V ₁ for each of the first auxiliary transmission hydraulic cylinders 12, and an auxiliary control valve V ₂ for the forward/reverse transmission hydraulic cylinder 11.
are connected to the hydraulic pump P in parallel. and,
The piston of each hydraulic cylinder 10A is also used as a sliding spool, and a 3-position switching valve is installed.
An oil passage that supplies pressurized oil from the switching valve S ₁ , which is composed of four valves S ₁ , S ₂ , S ₃ , and S ₄ , and is composed of the hydraulic cylinder 11 for forward/reverse shifting, to the hydraulic cylinder 13 for clutch operation. 14, and pilot pressure operated switching valves T ₁ , T ₂ , T ₃ for opening and closing the oil passage 14.
A switching valve configured of three hydraulic cylinders arranged in series, and each of the main gear shifting hydraulic cylinders 10A, 10B and the first sub-shifting hydraulic cylinder 12.
The valves S _{1 ,} T ₁ , T 2 , and T ₃ are provided to be operated by pressure oil from S 3 , S ₄ , and S ₂ , and control the operation of the clutch operation cylinder ₁₃ . In order to switch to the on operation position only in the transmission state of the gear transmission H ₁ , the forward/reverse gear transmission H ₂ , and the first auxiliary gear transmission H ₃ , the switching operation is automatically performed in conjunction with the gear shifting operation. It is configured.

However, when one of the two hydraulic cylinders 10A, 10B of the main gear transmission _H1 is operated to the gear shifting side, the other hydraulic cylinder is operated and held in the shifting neutral position by pressure oil. be. Further, the second auxiliary gear transmission _H4 is provided with a shifter that can be operated using a speed change lever. Furthermore, the transmission 7 and transmission clutch 9 for the power take-off shaft 8 are configured to be hydraulically operated in the same manner as the above-mentioned traveling transmission structure.

A main relief valve 15 is provided on the flow side of the main and auxiliary control valves V ₁ , V ₂ and the clutch operation control valves S ₁ , T ₁ , T ₂ , T ₃ , and the drained oil from the main relief valve 15 is used for lubrication. Therefore, the power is supplied to the transmission clutch C.

However, in the figure, N and F ₁ to F ₈ each indicate the operating position of the main control valve V ₁ , and F and R are
The operating position of the auxiliary control valve V ₂ is shown.

And pilot operation oil passages 19A, 1 for operating the gear shifter operating hydraulic cylinders 10A, 10B of the main gear transmission _H1 to the neutral gear side.
The oil passage 19A on the low speed side of 9B is closed by the main control valve V ₁ when switching the main gear transmission H ₁ to 3rd or 4th speed,
When switching the main gear transmission _H1 from the first or second speed to the third or fourth speed, the hydraulic cylinder 10A for operating the low speed shifter is configured not to operate.

Further, this tractor is constructed so that the traveling speed can be electrically changed by a speed change operation section 19 provided in the control section D, which will be described in detail below.

As shown in FIGS. 5 to 10, the main control valve _V1 is of a so-called rotary type, in which oil passages are switched by rotational operation.
Further, a direct current electric motor 22 capable of forward and reverse rotation is connected to the rotary operation shaft 20 of the valve V ₁ via a reduction gear device 21.
is installed. The speed reducer 21 is provided with a rotating shaft 21a extending therethrough and connected to the rotating operation shaft 20, and a potentiometer 23 is attached to the other end of the shaft 21a.

Further, the speed change operation section 19 controls the main control valve _V1 at the neutral position N and ₈ indicated by _F1 to F8.
Nine push switches SW are provided so that the gears can be selectively changed.
A lamp 24... is provided inside the..., and
A transparent member 25 is used on the upper surface of the switch Sw so that the lighting of the lamp 24 can be confirmed through the respective switch Sw. The push operation of the switch Sw... is input to the control device 26 composed of a CPU etc., and the control device 26 latches the signal of the operated switch Sw.
Turn on the lamp 24 of the operated switch Sw,
Further, a motor driver 27 composed of a power transistor or the like is operated to drive the electric motor 22. Next, the operating position of the control valve _V1 is detected by the potentiometer 23, and this detection result is fed back to the speed change operating section 19 via the A/D converter 28, and the control valve _V1 is operated to a predetermined position. Then, the operation of the motor driver 27 is stopped and the gear shifting operation is completed.

As shown in FIGS. 2 and 10, the tractor is configured so that the seating direction of the operator can face rearward by changing the seat 18, etc. In this case, the speed change operation section 19 The speed change operation section 19 is connected to a control device 26 on the vehicle body side by a flexible electric cord 29 so that a speed change operation can be performed. In other words, when the operator is seated facing the front of the vehicle, the gear shift operation section 19 can be installed on the meter panel 16, and when the operator is seated toward the rear of the vehicle, the shift operation section 19 can be accessed from the meter panel 16. 19 can be removed and attached to the bracket 30 at the rear of the vehicle for easy gear shifting operations.

[Another example]

In this embodiment, a synchronized mesh gear transmission was used to constitute the multi-stage transmission mechanism A, but instead of this, a large number of gears are arranged in mesh with each other, and a plurality of hydraulic clutches are installed in this gear transmission system. It may be applied to a multi-stage transmission mechanism configured with an interposed so-called hydraulic clutch transmission, and
The present invention may be implemented by providing a multi-stage transmission mechanism that is configured to be able to change speeds using a shift gear with a hydraulic actuator that can operate the shift gear.

Further, in this embodiment, the electric motor 22 capable of forward and reverse rotation is used to operate the control valve _V1 , and the amount of operation of the valve is detected by the potentiometer 23, but instead of this, an electric motor 22 is used. The potentiometer 23 may be omitted by using a stepping motor, a synchronous motor, or the like whose driving rotation speed or rotation angle can be controlled by a power supply current. Also, the valve may be operated by a solenoid instead of an electric motor, and these motors,
The solenoid is referred to as an electric actuator 22.

[Brief explanation of the drawing]

The drawings show an embodiment of the working vehicle according to the present invention, FIGS. 1 and 2 are overall side views of the tractor with the seat seating direction changed, and FIGS. 3 and 4 show the drive system of the hydraulic transmission. 5 and 6 are perspective views of the gear shift operation section and a cross-sectional view of the switch section, FIG. 7 is a perspective view of the drive operation structure of the hydraulic valve, and FIG. 8 is the gear shift operation system. The block diagram, FIGS. 9 and 10 are side views of the control section in which the seating direction of the seat is changed, respectively. 18... Driver's seat, 19... Gear shift operation section, 22...
...Electric actuator, 26...Control device, 29
...electrical cord, Sw...switch.

Claims (1)

[Claims for Utility Model Registration] 1. The driving transmission mechanism is configured to be controlled to be switched in multiple stages by an electric actuator 22 whose operation is controlled by a switch selection operation of a transmission operation unit 19 consisting of a group of switches Sw. A control device 26 disposed on the vehicle body side via a flexible electric cord 29 connects the speed change operation section 19 of the
The work vehicle is connected to the vehicle and has its gear shift operation section 19 removably attached to a position near the driver's seat 18. 2 Single push-button switch type gear shift operation section 19
The work vehicle according to claim 1 of the utility model registration claim, wherein the work vehicle is configured to be able to change its mounting position at a plurality of locations near the driver's seat 18.