JPH1076972A - Hydraulic travelling agricultural working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent impact force to an operator at the time of stopping by providing a second operation area to reduce discharge of each variable flow rate control pump through a pair of electric working means by a control means and a third operation area where a brake system brakes a driving wheel. SOLUTION: A pump operation part is provided in a pump operation part case 80, an arm 161 for actuation as an output end part of the pump operation part is installed on a bottom part of the pump operation part case 80, and rod type direct-coupled links 126, 127 are respectively interposed between the arm 161 for actuation and pump operation levers 128, 129 of variable flow rate control pumps PL, PR. Revolving radiuses of the arm 161 for actuation to push, pull and slide the direct-coupled links 126, 127 and each of the pump operation levers 128, 129 are roughly the same. At the time of steering and operating a frame body, working angles of the arm 161 for actuation and each of the pump operation levers 128, 129 become roughly the same, and it is possible to improve a rectilinear propagating property and operating feeling of the frame body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic traveling agricultural working machine having a crawler traveling section.

[0002]

2. Description of the Related Art Conventionally, as one form of a hydraulic traveling agricultural machine, a pair of traveling hydraulic motors are connected to a pair of variable flow control pumps interlocked with an engine through a closed circuit oil passage, and each traveling hydraulic pressure is controlled. Drive wheels provided on a pair of left and right crawler type traveling units are connected to the motor in an interlocking manner, and each of the variable flow control pumps is operated by two steering / shift operation levers.
There are some aircraft that can be changed to any of a straight traveling mode, a gentle turning mode, a pivot turn mode, and a spin turn mode.

[0003] In addition, a brake device is provided for the drive wheel,
The brake device can be operated by a brake pedal.

[0004]

However, the hydraulic traveling agricultural working machine described above still has the following problems.

That is, when stopping the body, the brake device is braked by depressing the brake pedal.
When the aircraft suddenly stops, the operator's body jumps forward due to inertial force, giving a sense of fear to the operator or injuring the operator.

Further, when the brake braking operation is released, the aircraft is suddenly started to switch to the operation mode immediately before the brake braking operation, that is, the high-speed traveling mode. Or cause an accident.

[0007]

Therefore, according to the present invention, a pair of traveling hydraulic motors are connected to a pair of variable flow control pumps interlocked with the engine via a closed circuit oil passage, and each traveling hydraulic motor is Drive wheels provided on a pair of left and right crawler-type traveling units are interlocked, and each of the variable flow rate control pumps is operated by steering operation means and speed change operation means to increase / decrease each traveling hydraulic motor. By causing the left and right traveling units to travel respectively, the aircraft can be changed to any of a straight traveling mode, a gentle turning mode, a pivot turn mode, and a spin turn mode,
The steering operation means includes a first steering operation range for setting a gentle turning mode, a second steering operation range for setting a pivot turn mode, and a third steering operation range for setting a spin turn mode. And, in a hydraulic traveling agricultural work machine in which a brake device provided on the drive wheel can be operated by a brake braking operation means, a steering operation angle detection means for detecting a steering operation angle of the steering operation means, Shift operation angle detection means for detecting a shift operation angle of the shift operation means, vehicle speed detection means for detecting vehicle speed, brake braking operation detection means for detecting brake braking operation of the brake braking operation means, and the pair of variable flow control A pair of electric actuation means interlockingly connected to each swash plate angle control member for controlling the swash plate angle of the pump,
Control means for connecting each of the detection means to the input side and connecting the pair of electric actuation means to the output side, wherein the brake braking operation means is based on a detection result by the brake braking operation detection means. A first operating area in which the control means increases the reduction ratio of each traveling hydraulic motor via a pair of electric operating means, and a pair of electric operating means based on a detection result by the brake braking operation detecting means. A hydraulic operating agricultural working machine characterized by having a second operating area for reducing the discharge rate of each variable flow control pump through the means and a third operating area for the brake device to brake the drive wheels. Is what you do.

The present invention is also characterized in that the brake braking release operation by the brake braking operation means is performed through a third operation area → a second operation area → a first operation area.

[0009]

Embodiments of the present invention will be described below.

The hydraulic traveling agricultural working machine according to the present invention enables high-speed traveling (for example, 35 km / h) and improves the operation system accordingly.

That is, in the hydraulic traveling agricultural working machine, a pair of traveling hydraulic motors are connected to a pair of variable flow control pumps linked to the engine via a closed circuit oil path, and a pair of left and right traveling hydraulic motors are connected to each traveling hydraulic motor. By interlocking the drive wheels provided on the crawler type traveling unit, operating each of the variable flow rate control pumps by the steering operation means and the speed change operation means, and increasing / decreasing each traveling hydraulic motor, The traveling units on the left and right sides are respectively operated to travel, and the aircraft can be changed to any of a straight running mode, a gentle turning mode, a pivot turn mode, and a spin turn mode, and the steering operation means is set to a slow turning mode. A first steering operation range for performing, a second steering operation range for performing the pivot turn mode, and a third steering operation range for performing the spin turn mode, and The brake device provided to the drive wheel comprises a basic structure that can be operated by braking operation unit, and it has the characteristics in the following configuration.

(1) Steering operation angle detecting means for detecting the steering operation angle of the steering operation means, shift operation angle detecting means for detecting the shift operation angle of the shift operating means, and vehicle speed detecting means for detecting the vehicle speed Rotation speed detection means for detecting the rotation speed of the engine; brake braking operation detection means for detecting the brake braking operation of the brake braking operation means; and each swash plate for controlling the swash plate angle of the pair of variable flow control pumps. A pair of electric actuating means interlockingly connected to the angle control member, and a control means connecting each of the detecting means to the input side and connecting the pair of electric actuating means to the output side are provided.

When the steering operation means and the speed change operation means are respectively operated in this way, the detection results are inputted to the control means from the steering operation angle detection means and the speed change operation angle detection means, respectively, and the control means is operated by the control means. Based on the detection result, a pair of electric operating means is operated, each electric operating means operates a pair of swash plate angle control members, and each swash plate angle control member is a pair of variable flow control pump swash plate. By controlling the angle, the aircraft can be changed to any one of a forward / backward straight traveling mode, a left / right gentle turning mode, a left / right pivot turn mode, and a left / right spin turn mode.

Further, the swash plate angle control members of the pair of variable flow control pumps are operated by a pair of electric operating means, respectively, so that the discharge amount of each variable flow control pump can be controlled. By controlling each traveling hydraulic motor driven by the variable flow control pump with high precision and synchronizing both traveling hydraulic motors, it is possible to ensure good straightness of the body.

Further, as described above, by electrically controlling each drive unit, it is possible to improve the response of the operation of the traveling unit to each operation of the steering operation means and the speed change operation means. I have.

(2) When the vehicle speed detecting means detects a vehicle speed higher than a predetermined speed range, the control means slowly turns the operating range of the electric operating means for operating each swash plate angle control member. Only the mode is limited to the permissible range, so that even when the operator performs a sharp turning operation during high-speed driving, the aircraft does not turn sharply and safety can be ensured well. ing.

(3) When the vehicle speed detecting means detects a vehicle speed higher than a predetermined speed range, the operating speed of each electric operating means for operating each swash plate angle control member is reduced by the control means. In this way, even when the operator performs a sharp turning operation during high-speed driving, the aircraft does not turn sharply, and good safety can be ensured. (4) Steering By making the steering operation speed faster by operating the steering operation means in proportion to the speed at which the operation means is steered and the speed at which the electric actuation means is operated, the aircraft operates faster and the steering operation means is operated slowly. Then, the body also moves slowly, so that the operator can obtain a comfortable operation feeling.

(5) When the steering operation angle detecting means detects the neutral position of the steering operating means and the vehicle speed detecting means detects the vehicle speed, each swash plate angle control by a pair of electric operating means. By making the operation amounts of the members the same, the discharge amounts of the pair of variable flow control pumps are made the same, the driving power of each traveling hydraulic motor driven by each variable flow control pump is made the same, It ensures that you can go straight.

(6) The ground position detecting means is connected to the input side of the control means, and based on the detection result of the ground position detecting means, the control means controls the right and left traveling sections through a pair of electric operating means. By making it possible to correct the speed difference, it is possible to ensure good straightness of the aircraft.

(7) Steering operation angle regulating means for regulating the steering operation angle of the steering operation means is provided, and when the vehicle speed detecting means detects a vehicle speed higher than a predetermined speed range, control is performed. By driving the steering operation angle restricting means by the means, the steering operation range of the steering operation means is regulated to be within the first steering operation range, thereby restricting sudden turning of the aircraft at high speed traveling. Therefore, safety can be ensured well.

(8) When the vehicle speed detecting means detects a vehicle speed higher than a predetermined speed range, the control means inputs an input signal input from the steering angle detecting means to the control means, By configuring the input signal to be limited to the input signal within the steering operation range, a sharp turn of the aircraft at the time of high-speed traveling is restricted, and good safety can be ensured.

(9) The first brake operation means for increasing the speed reduction ratio of each traveling hydraulic motor via a pair of electric operating means by the control means based on the detection result by the brake braking operation detection means. And a second operation area in which the control means reduces the discharge amount of each variable flow control pump through a pair of electric operating means based on the detection result by the brake braking operation detecting means, and a braking device controls the driving wheels. By having a third operation area for brake braking, and sequentially operating the brake braking operation means from the first operation area → the second operation area → the third operation area, the aircraft can be gently stopped. In addition, it is possible to eliminate the impact force to the operator at the time of stop.

(10) The brake braking release operation by the brake braking operation means is performed through the third operation area → the second operation area → the first operation area, and the aircraft is always started at a low speed to prevent an accident due to a quick start. To be able to.

(11) Each traveling section has a drive wheel formed to have a diameter larger than that of the idler wheel to enable high-speed traveling, so that a long-distance travel can be easily performed by self-propelled traveling.

[0025]

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

A shown in FIG. 1 is an agricultural tractor as a hydraulic traveling agricultural working machine according to the present invention. The agricultural tractor A is provided with various working devices such as a rotary tilling working device (not shown) at the rear. A three-point link type elevating / swinging mechanism B is connected so as to be able to ascend / descend / swing freely so that work by various working devices can be performed.

As shown in FIGS. 1 to 3, the agricultural tractor A has a body frame 3 suspended laterally between traveling frames 2L and 2R of a pair of left and right crawler traveling parts 1L and 1R. A motor unit 4 such as an engine E is provided at a front portion of the engine 3 and a cabin 5, a hydraulic oil tank 6, and a fuel tank 7 are provided at a rear portion.
And are arranged. 8 is a front weight and 9 is a battery.

As shown in FIGS. 1 to 3, the right and left traveling parts 1L and 1R are respectively composed of traveling frames 2 extending in the front-rear direction.
Drive wheels 10L, 10R are mounted on the front ends of L, 2R, and idler wheels 11L, 11R are mounted on the rear ends of the running frames 2L, 2R, and the crawler tracks 12L, 12R are wound between the two wheels 10L, 10R, 11L, 11R. Turning.
13 is an equalizer.

The drive wheels 10L, 10R are connected to idler wheels 11L, 11R.
It is formed with a diameter approximately twice as large as R, and tracks 12L and 12R.
Is formed as narrow as possible, and the ground contact area of the crawler tracks 12L, 12R is made as small as possible.

Each drive wheel 10L, 10R is provided with a variable left and right traveling hydraulic motor ML, MR, respectively.

In this manner, the left and right traveling portions 1L and 1R allow the aircraft to travel at a high speed (for example, 35 km / h).

As shown in FIGS. 1 and 4, an operating section 29 is provided in the cabin 5. The operating section 29 is provided with an operating section 31 in front of a floor section 30, and the operating section 31 is provided with an operating section 31. Seat 32 in rear position
The left lever column 33 is arranged on the left side of the seat 32, and the right lever column 34 is arranged on the right side.

The operating section 31 is provided on an operating column 35 erected on the floor 30 with a circular handle 36 forming a part of a steering operating means 88 described later, an accelerator lever 37, a PT
The O-clutch lever 38, the display unit 39, and the electric / mechanical changeover switch 14 are mounted. 40 is a brake pedal as a brake braking operation means, and 41 is a parking brake lever.

The seat 32 is attached to the floor 30 so that the front and rear slide position is adjustable and the seat 32 is rotatable by a predetermined angle (for example, 20 degrees) to the right around the vertical axis. 43 is a seat rotation lever, and 44 is a hydraulic valve adjustment knob.

The left lever column 33 is provided with a PTO shift lever 45 and an accessory box 46.

In the right lever column 34, a speed change lever 47 forming a part of a speed change operation means 89 to be described later and various operation levers for operating the working device are centrally arranged.
As various operation levers, a lowering position setting lever 48 for setting a lowering position of various working devices by an elevating / swinging mechanism B.
And first, second, and third working device operation levers 49, 50, and 51. 52 is a control box.

As described above, the operator rotates the seat 32 to the right, thereby turning the handle 36 with the left hand, setting the upper body in a half body state, turning the face backward, and further using the right hand. By operating various operation levers arranged in a centralized manner, the working device connected to the rear of the machine body can be operated safely and reliably, and the working efficiency can be improved.

As shown in FIGS. 5 and 6, a front transmission (not shown) is interlockedly connected to the engine E, and a rear transmission 65 provided at the rear of the body frame 3 at the front transmission. And a pair of variable flow control pumps PL and PR and a hydraulic pump for work equipment lift
P1 and the charge pump P2 are interlocked and connected in the front-rear direction, and a hydraulic motor ML for left running is interlockedly connected to the variable flow control pump PL via a closed hydraulic circuit (not shown). , A right running hydraulic motor MR is interlocked and connected via a closed hydraulic circuit.

As shown in FIGS. 5 and 6, the operating section 31 has a pump operating section case 80 which spans between a pair of left and right side frames 3a, 3b forming a part of the body frame 3, and The lower end of a lower transmission shaft 81a extending upward is interlockingly connected to a steering operation shaft 120 protruding upward from the front center portion of the ceiling wall of the pump operation unit case 80, and the upper end of the lower transmission shaft 81a is connected. Transmission shaft 81 extending upward to the part
The lower end of the upper transmission shaft 81d extending rearward and upward to the upper end of the midway transmission shaft 81b is interlocked via the upper universal joint 81e. Connected to the upper transmission shaft 81d
The steering operation means 88 is formed by attaching the handle 36 to the upper end of the steering wheel.

The transmission arm 172 is attached to the transmission shaft 121 protruding from the left side wall of the pump operation section case 80 by the boss 17.
3 and the transmission arm 172 and the transmission lever
A speed change operating means 89 is formed by interposing an interlocking wire (not shown) between the gear 47 and the gear 47.

A pump operating unit 91 is provided in the pump operating unit case 80, and operating arms 161 and 162 as output ends of the pump operating unit 91 are attached to the bottom of the pump operating unit case 80. Bar-shaped direct links 126 and 127 are interposed between the pump operation levers 128 and 129 of the variable flow control pumps PL and PR 161,162, respectively.

In addition, each of the operating arms 161 and 162 for pushing and pulling the direct link 126 and 127 and the pump operating lever 12
The turning radii of 8,129 are assumed to be substantially the same.

As described above, when the body is steered, the operating arms 161 and 162 and the pump operating levers 128 and
The operating angles of the 129 are substantially the same, so that the straightness and operation feeling of the aircraft can be improved.

Therefore, when the handle 36 is turned, power is transmitted as follows. Upper transmission shaft 81d → Upper universal joint 81e → Midway transmission shaft 81b → Lower universal joint 81c → Lower transmission shaft 81a → Rotational operation force is transmitted to the steering operation shaft 120 of the pump operation unit 91, and the pump operation unit 91 operating arms 85L, 85R → a pair of directly connected links 87
L, 87R → A pair of pump operation levers 86L, 86R → A pair of variable flow control pumps PL, PR → Hydraulic motors ML, MR for left and right traveling →
Crawler type left and right running parts 1L, 1R.

In this way, the steering operation of the left and right traveling units 1L and 1R can be performed by rotating the handle 36,
The aircraft can be changed to any of the forward / backward straight forward mode, left / right slow turn mode, left / right pivot turn mode, and left / right spin turn mode, and the steering wheel 36 has a first steering operation range for the slow turn mode. , A second steering operation range for entering the pivot turn mode, and a third steering operation range for entering the spin turn mode.

By rotating the transmission lever 47 in the front-rear direction, the left and right traveling hydraulic motors M are driven.
The speed and direction of rotation of L and MR can be changed,
The switching operation of the forward / reverse / stop of the body and the speed adjusting operation can be performed.

In the above-described configuration, the gist of the present invention is that the steering operation for changing the aircraft to any one of the forward / backward straight traveling mode, the left / right gently turning mode, the left / right pivot turn mode, and the left / right spin turn mode is described above. The power can be transmitted mechanically by the configuration described above, and the power can be controlled by an electric system.The switching can be performed by the electric / mechanical system provided in the operation unit 31. The changeover switch 14 is used.

That is, the control means 15 shown in FIG. 7 is accommodated in the control box 52 provided in the operation section 29,
On the input side of the control unit 15, the electric / mechanical changeover switch 14, the steering operation angle detection unit 16, the shift operation angle detection unit 17, the vehicle speed detection unit 18, the rotation speed detection unit 19, The brake braking operation detecting means 20, the auxiliary speed change switch 21, and the ground position detecting means 22 are connected, while the output side of the control means 15 has a pair of clutch means 23L, 23R and a pair of electric operating means. 24L and 24R are connected.

The steering operation angle detecting means 16 includes a steering operation means 88.
Attached to the upper end of the steering shaft 120 which forms part of
The steering operation angle of the handle 36 can be detected, and a rotation angle detection sensor, for example, a potentiometer can be used as the steering operation angle detection means 16.

The shift operation angle detecting means 17 is provided with a shift operation means 89.
Is mounted on a lever support shaft 47a of a transmission lever 47 forming a part of the transmission lever 47 to detect a transmission operation angle of the transmission lever 47. As the transmission operation angle detecting means 17, a rotation angle detection sensor, for example, A potentiometer can be used.

The vehicle speed detecting means 18 can detect the rotation speed of the drive shafts 10La, 10Ra of the drive wheels 10L, 10R, and can use a rotation speed detection sensor.

The rotation speed detecting means 19 can detect the rotation speed of the engine E.
A rotation speed detection sensor can be used.

The brake braking operation detecting means 20 is attached to a pedal support shaft 40a of the brake pedal 40 so as to detect a depression operation angle of the brake pedal 40. A detection sensor, for example, a potentiometer, can be used.

The auxiliary speed change switch 21 is attached to the grip portion of the speed change lever 47, and the swash plates 201 and 202 provided on the variable left and right traveling hydraulic motors ML and MR by the switching operation of the auxiliary speed change switch 21 (see FIG. 21). ) Can be changed between a standard (low-speed) operation position and a high-speed operation position.

The ground position detecting means 22 receives a signal from an artificial satellite in a GPS (Global Positioning System) and inputs the signal to the control means 15. Based on the input signal, the control means 15 controls the airframe. Electric actuation means for driving the vehicle in a preset direction
24L, 24R is feedback controlled to drive the left and right traveling units 1L, 1
The speed difference of R is corrected. Such control is
In particular, the present invention is suitable for the case where the aircraft is caused to travel straight, and the control based on the detection result of the steering operation angle detecting means 16 is selectively performed.

A pair of clutch means 23L and 23R are provided with swash plate angle control members 238L and 238R (provided on swash plate angle control means 236L and 236R for controlling the angles of the swash plates 198 and 199 of the variable flow control pumps PL and PR, respectively). 21) and the pump operation lever
Interposed between the levers 128, 129 and the lever support shafts 128a, 129a, the connection / disconnection operation is performed via the control means 15 by the switching operation of the electric / mechanical changeover switch 14.

The pair of electric actuating means 24L, 24R are operatively connected to swash plate angle control members 238L, 238R for controlling the swash plate angles of the respective variable flow control pumps PL, PR. twenty four
Each swash plate angle control member 238L, 238R can be operated by R, and for example, a servo motor can be used as each of the electric operating means 24L, 24R.

In this way, when the electric / mechanical switch 14 is switched to the mechanical side, the clutch means 23L and 23R are connected and the switch 14 is switched to the electric side. When operated, each clutch means 23L,
23R is in a cut-off state, so that mechanical control of the variable flow control pumps PL and PR via the pump operating section 91 is disabled, and only electrical control is enabled.

In this state, the handle 36
When the shift lever 47 is operated, the detection results are input to the control means 15 from the steering operation angle detection means 16 and the shift operation angle detection means 17, respectively. By operating the electric actuation means 24L, 24R, each electric actuation means 24L, 24R actuates a pair of swash plate angle control members 238L, 238R, and each swash plate angle control member 238L, 238R.
Can control the swash plate angle of the pair of variable flow control pumps PL and PR to change the aircraft to any of the forward / backward straight forward mode, left / right gentle turning mode, left / right pivot turn mode, and left / right spin turn mode .

At this time, since the hydraulically traveling agricultural working machine A can travel at a high speed, it can easily move a long distance.

Moreover, a pair of variable flow control pumps PL, PR
The swash plate angle control members 238L and 238R are operated by a pair of electric actuation means 24L and 24R, respectively, so that the discharge amount of each of the variable flow control pumps PL and PR can be controlled. By accurately controlling each of the traveling hydraulic motors ML and MR driven by the control pumps PL and PR and synchronizing the two traveling hydraulic motors ML and MR, it is possible to ensure good straightness of the aircraft. .

Further, as described above, since the drive units are electrically controlled, the responsiveness of the operation of the left and right traveling units 1L and 1R to each operation of the steering wheel 36 and the shift lever 47 can be improved. .

When the vehicle speed detecting means 18 detects a vehicle speed higher than a predetermined speed range (for example, 10 km / h), the electric operating means 24L for operating the swash plate angle control members 238L, 238R. , 24R is controlled by the control means 15 to a range in which only the gentle turning mode is allowed.

Therefore, even when the operator performs a sharp turning operation while traveling at a vehicle speed higher than the set speed range, the aircraft does not turn sharply, and safety can be secured well.

The speed at which the steering wheel 36 is steered and the speed at which the electric operating means 24L, 24R are operated are proportional to each other via the control means 15. If the handle 36 is operated quickly, the body also operates quickly. If the handle 36 is operated slowly, the body also operates slowly, so that the operator can obtain a comfortable operation feeling.

When the steering operation angle detecting means 16 detects the neutral position of the steering wheel 36 and the vehicle speed detecting means 18 detects the vehicle speed, the pair of electric operating means 24
The L and 24R are controlled so that the aircraft goes straight.

That is, when the steering operation angle detecting means 16 detects the neutral position of the handle 36, the operation amounts of the respective swash plate angle control members 238L, 238R by the pair of electric operating means 24L, 24R are made equal. By doing, a pair of variable flow control pumps
The discharge volume of PL and PR is assumed to be the same and each variable flow control pump P
The driving force of each traveling hydraulic motor ML, MR driven by L, PR is made equal. Therefore, the straightness of the aircraft can be favorably secured.

The brake pedal 40 is, as shown in FIG.
A first operation area Z1 for increasing the reduction ratio of each of the traveling hydraulic motors ML, MR via the pair of electric operating means 24L, 24R by the control means 15 based on the detection result by the brake braking operation detecting means 20; A second operation area Z2 for reducing the discharge amount of each of the variable flow control pumps PL and PR by the control means 15 via the pair of electric actuation means 24L and 24R based on the detection result by the brake braking operation detection means 20; Brake equipment 195,
196 is the third operating area Z3 that brakes the drive wheels 10L and 10R.
A brake operating arm 26 protrudes from the pedal support shaft 40a, and a brake braking switching valve 27 attached to the front wall of the pump operating section case 80 is connected to the brake operating arm 26 by a connecting rod 28. The brake-brake switching valve 27 operates the brake pedal 40 in the third operation range.
When the switch is operated up to Z3, it switches and the brake device 195, 19
6 is braked.

As described above, the brake pedal 40 is sequentially operated from the first operation area Z1, the second operation area Z2, and the third operation area Z3, so that the machine body can be gently stopped. The impact force on the operator can be eliminated.

The brake braking release operation by the brake pedal 40 is performed through the third operation area → the second operation area → the first operation area.

In this way, the aircraft is always started at a low speed, so that an accident due to a quick start can be prevented.

In addition to the above-described control, the following control can be appropriately adopted.

That is, when the vehicle speed detecting means 18 detects a vehicle speed higher than a predetermined speed range (for example, 10 km / h), the control means 15 controls the swash plate angle control members 23
8L, 238R is operated by changing the current value of the signal output to each electric actuating means 24L, 24R,
By reducing the operating speed of the 24R, the speed at which the aircraft responds to the turning operation of the steering wheel 36 is reduced, and the agile turning operation of the aircraft during high-speed traveling can be prevented, ensuring good safety. .

When the vehicle speed detecting means 18 detects a vehicle speed higher than a predetermined speed range (for example, 10 km / h), the input signal inputted to the control means 15 from the steering operation angle detecting means 16. The control means 15 is configured to limit the input signal within the first steering operation range, thereby restricting the turning of the aircraft during high-speed traveling to a range in which only the slow turning mode is permitted, thereby improving safety. It can be secured well.

Further, the operation lever 47 is moved in a very
When the steering wheel 36 is turned while operating within a speed of 5 km / h or less, the traveling portion on the turning direction side (inside) does not change the speed, and the traveling portion on the opposite side (outside) is increased in speed. By doing so, the turning of the aircraft can be performed quickly, and a comfortable operation feeling can be given to the operator.

On the other hand, if the steering wheel 36 is turned while the shift lever 47 is being operated within the medium / high speed range (for example, 5 km / h to 35 km / h), the traveling portion on the turning direction side (inside) is decelerated, and The side (outside) traveling unit does not change the speed, so that the body turns smoothly, and it is possible to give a comfortable operation feeling without giving the operator a fear of sudden turning. .

When the amount of turning operation (steering angle) of the handle 36 is large, the sub-transmission switch 21 automatically switches from the high-speed operation position to the standard operation position, thereby turning the aircraft sharply. Prevention can also ensure safety.

The control based on the detection result by the vehicle speed detecting means 18 is performed by using the rotation speed detecting means 19, the shift operation angle detecting means 17, or the sub-shift switch 21 instead of the vehicle speed detecting means 18. You can also do it.

In addition to the above control, the steering operation angle of the steering wheel 36 is controlled by the control means 15 based on the detection result by the vehicle speed detection means 18 as shown in FIG. It can also be driven to regulate.

That is, the steering operation angle restricting means 55 is provided as shown in FIG.
As shown in FIG. 8, a pair of upper and lower disks is provided on the upper end of the steering operation shaft 120 protruding upward from the ceiling wall of the pump operation unit case 80.
On the other hand, a high-speed turning restricting body 58 is arranged on the left side of the ceiling wall of the pump operation unit case 80 so as to face the lower disk 57, and a medium-speed turning is provided on the right side of the ceiling wall. The regulating body 59 is arranged to face the upper disk 56.

Then, as shown in FIGS. 10 and 11,
With the handle 36 in the neutral position, the lower disc 57
An abutment piece 57a protrudes from the right end of the. WL is the steering operation range of the steering wheel to the left, and WR is the steering operation range of the steering wheel to the right.

The high-speed turning restricting body 58 is attached to a solenoid 60 connected to the output side of the control means 15 and a movable iron core 60a of the solenoid 60 so as to face the left peripheral surface of the lower disk 57. And a regulating piece 61 arranged to be able to advance and retreat,
A contact surface where the contact piece 57a contacts the front and rear ends of the regulating piece 61.
61a and 61b are formed. 61c is a guide hole, and 61d is a guide pin.

In this way, when the vehicle speed detecting means 18 detects a high speed (for example, 15 km / h or more to 35 km / h), the control means 15 outputs a signal to the solenoid 60,
The solenoid 60 advances the restricting piece 61 to a position close to the lower disk 57. As a result, as shown in FIG. 57a contacts one of the contact surfaces 61a and 61b of the regulating piece 61,
The rotation operation range of the handle 36 is restricted. WL1 is a left-hand steering wheel turning operation range during high-speed running, and WR1 is a right-hand steering wheel turning operation range during high-speed operation.

Then, as shown in FIGS. 12 and 13,
With the handle 36 in the neutral position, the upper disc 56
A contact piece 56a protrudes from the left end portion of the.

The medium-speed turning restricting body 59 is attached to a solenoid 62 connected to the output side of the control means 15 and a movable iron core 62a of the solenoid 62 so as to face the right peripheral surface of the upper disk 56. And a regulating piece 63 arranged to be able to advance and retreat.
A contact surface where the contact piece 56a contacts the front and rear ends of the restriction piece 63.
63a and 63b are formed. 63c is a guide hole, and 63d is a guide pin.

In this way, when the vehicle speed detecting means 18 detects the medium speed (for example, 5 km / h or more to less than 15 km / h), the control means 15 outputs a signal to the solenoid 60 and the solenoid 60 regulates. The piece 63 is advanced to a position close to the upper disk 56, and as a result, as shown in FIG.
Even if the handle 36 is turned greatly, the contact piece 56 of the disc 56
The contact a contacts one of the contact surfaces 63a and 63b of the restricting piece 63 so that the range of rotation of the handle 36 is restricted. WL2 is a left-hand steering wheel turning operation range during middle-speed operation, and WR2 is a right-hand steering wheel turning operation range during medium-speed operation.

With the above configuration, in this embodiment,
As shown in Table 1, during high-speed running, the handle 36 is restricted within the handle rotation operation range WL1 and WR1, so that neither left-right pivot turn nor right-left spin turn can be performed.

When the vehicle is running at a medium speed, the steering wheel 36 is restricted within the steering wheel turning operation range WL2, WR2 so that the left and right spin turns cannot be performed. When the vehicle is running at a low speed (for example, less than 5 km / h), the vehicle can be turned in any of the left and right gentle turns, the left and right pivot turns, and the left and right spin turns.

[0089]

[Table 1]

Therefore, it is possible to restrict the sharp turning of the body during middle / high speed running and to ensure good safety.

Next, the pump operating section case 80 will be described in more detail.

The pump operating section case 80 is shown in FIGS.
As shown in the figure, a cast case main body 92 having an opening and supporting the pump operating portion 91 and a cast closing body 93 closing the opening of the case main body 92 are formed in two parts. I have.

A plurality of bolt screw holes 94 are formed in the periphery of the opening of the case body 92 in the vertical direction.
A plurality of bolt insertion holes 95 vertically aligned with the bolt screw holes 94 are formed in the periphery of the bolt 93, and bolts 96 are inserted into both holes 94 and 95, so that the case body 92 and the closing body 93 are closed. And four bolt insertion holes 95, 95, 95, 9
5 By inserting bolts 96, 96, 96, 96 through bolt holes 97 formed in the stays 90, 90, 90, 90, the stay 90, the case body 92, and the closing body 93 are connected. They are integrally fastened together.

In this manner, the operation of attaching / detaching the pump operating section case 80 to / from the body frame 3 can be easily performed, and the case body forming the pump operating section case 80 can be easily operated.
The connection and disconnection of the closing body 92 and the closing body 93 can be performed at the same time, so that maintenance of the pump operating section 91 supported by the case main body 92 can be performed easily.

Further, at the rear of the left and right side walls of the case main body 92, a transmission shaft 12 forming a part of a pump operation section 91 described later is provided.
Left and right side shaft insertion holes 98 and 99 are formed to allow the 1 to pass through in the left and right direction. 170 and 171 are bearings.

The front part of the ceiling wall of the case body 92 and the closing body 93
Upper and lower shaft insertion holes 110 and 111 for vertically penetrating and inserting the steering operation shaft 120 are formed in the front portion thereof so as to face each other in the vertical direction. 174,175 are bearings.

Further, as shown in FIGS. 14 and 15, an arm support shaft 165 of a pump operation section 91, which will be described later,
Bosses 163 and 164 for supporting the rotor 166 are formed, and detent mechanisms DL and DR for holding the rotor support arms 159 and 160 in a neutral state are provided.

As shown in FIG. 6, the detent mechanisms DL and DR are respectively formed with cylindrical bottomed neutral holding ball containers 112 and 113 protruding downward from the right and left sides of the lid 93, respectively. The neutral holding ball housings 112 and 113 contain neutral holding balls 114 and 115 and springs 116 and 117 for elastically urging the neutral holding balls 114 and 115 upward.

The neutral holding balls 114, 115
The rotor support arms 159, 160 are disposed immediately above the rotor support arms 159, 160, and ball engaging recesses 118, 119 are formed in the center of the lower surface of each rotor support arm 159, 160.

Thus, the rotor support arms 159, 16
14 is in a neutral state, that is, in a state of extending horizontally in the left-right direction as shown in FIGS. 14 and 15, the ball engaging recesses 118, 119 of the rotor support arms 159, 160
Neutral holding balls 114 and 115 which are pushed upward and urged by the springs 116 and 117 are engaged from below to maintain the neutral state.

Therefore, when the operator switches the transmission lever 47 between the forward switching position and the reverse switching position, the neutral holding balls 114 and 115 engage with the ball engaging recesses 118 and 119 at the neutral position. In order to be held neutral, the operator can experience the switching operation to the neutral position by the held response, while performing the switching operation to the forward or reverse switching position beyond the neutral position,
The operator must consciously perform the switching operation to the forward or reverse switching position, so that unintentional erroneous operation can be prevented, and safety can be ensured.

Next, the pump operating section 91 will be described.

That is, as shown in FIGS. 14 to 16, the pump operating section 91 is located at a position in front of the speed change shaft 121.
A slide shaft 122 is laid horizontally in parallel with 121. A pair of left and right slide bodies 123, 124 are fitted on the slide shaft 122 so as to be slidable in the axial direction, and a movable body 125 is provided between the slide bodies 123, 124. It is arranged. Each slide 123,124
Connected to the direct link 126,127, the direct link 126,127
Are connected to pump operation levers 128, 129 of a pair of variable flow control pumps PL, PR.

Therefore, the pump operating section 91 is connected to the direct link 12
The variable flow control pumps PL and PR are operated via 6,127 to control the steering of the traveling units 1L and 1R.

The moving body 125 has a base 130 mounted on the slide shaft 122 so as to be slidable in the axial direction, and a main body integrally mounted on the base 130 and disposed immediately in front of the slide shaft 122.
Abutment pieces 134 and 135 which abut on the projecting pieces 132 and 133 of the respective slide bodies 123 and 124 at both ends of the main body 131.
On the upper surface of the main body 131, a rack 136 extending in the left-right direction is fixed.

The rack 136 has a pinion gear 137
Are engaged. The pinion gear 137 is the steering operation shaft 120
The steering operation shaft 120 is linked to the lower end of the lower transmission shaft 81a of the handle 36 disposed above.

Therefore, when the handle 36 is rotated, the pinion gear 137 is rotated, and the rack 136 is slid in the left-right width direction in conjunction therewith, and the moving body 125 is slid accordingly.
5 slide bodies 123,
Move one side of 124.

The proximal ends 140, 141 of the guide support arms 138, 139 are loosely fitted on the outer peripheral surfaces of the slides 123, 124, respectively, and the detents 142, 143 are provided rearward from the respective proximal ends 140, 141.
And the rotation stoppers 142 and 143 are freely slidably fitted on the speed change shaft 121. 144 and 145 are rotation stoppers 14
It is a boss section connected to 2,143.

On the other hand, at the rear of each base end 140, 141, the boss 14
6,147 are formed in the vertical direction, and the upper ends of the pivot pins 148,149 having their axes oriented vertically are inserted into the bosses 146,147, and the lower ends of the pins 148,149 are inverted U-shaped in cross section and horizontally elongated. The center upper wall portions of the guide members 150 and 151 are rotatably mounted.

The swing arms 152 and 153 are respectively provided below the bosses 144 and 145, and the swing arms 152 and 153 are respectively provided.
The rear ends of the swing links 154, 155 are connected to the lower end of the guide member 3, and the upper ends of the guide members 150, 151 are connected to the front ends of the swing links 154, 155 by pivotal support. 156 is a pair of left and right boss portions 144, 1
This is a moving body neutral return spring interposed between the 45.

In the recesses of the guide members 150, 151 having an inverted U-shaped cross section, rotatable rotors 157, 158 are accommodated, respectively.
They are linked to the operating arms 161 and 162 via 159 and 160, respectively. The operating arms 161 and 162 are
The base end is attached to the lower end of a vertical arm support shaft 165, 166 pivotally supported through a boss 163, 164 on the bottom wall of the 80, while the rotor support arm 159, 160 is attached to the upper end of the arm support shaft 165, 166. At the same time, rotors 157 and 158 are attached to the tip.

In addition, the extending directions of the operating arms 161 and 162 and the rotor supporting arms 159 and 160 are
5,166 in the opposite direction and each rotor support arm
Rotors 157 and 158 attached to the tips of 159 and 160
Each of the actuating arms 16 is linked with the operation of rotating around the arm support shafts 165 and 166 while sliding in the recesses 150 and 151.
The tip of 1,162 pivotally moves about each arm support shaft 165,166 to a point symmetrical position with each rotor 157,158.

The operation arms 161 and 162 are connected to the pump operation levers 128 and 12 via the direct links 126 and 127, respectively.
Linked to 9

In such a configuration, the moving body 125 is slid by the rotation of the handle 36, and the sliding body 12 is moved.
3, 124 is moved along the slide shaft 122 and the speed change shaft 121, and the guides 150, 151 provided integrally with the slides 123, 124 are slid.

When the transmission shaft 121 is rotated by the transmission lever 47, each of the guide members 150, 151 is moved by the slide members 123, 1.
The operation arms 161 and 162 are pivoted about arm support shafts 165 and 166 around pivot pins 148 and 149 via swing links 154 and 155 connected to the arm 24, respectively.

Next, the movement of the left and right guides 150 and 151 when the handle 36 and the speed change lever 47 are operated will be described with reference to FIGS.

That is, the shift lever 47 is set to the neutral state,
At the same time, if the rotary handle 36 is also in the neutral state,
Left and right guide bodies 150,151, rotor support arms 159,160,
And, the operating arms 161 and 162 are, as shown in FIG.
Maintain a horizontal position.

When the shift lever 47 is shifted to the forward shift position from this state, the shift shaft 121 rotates, and the left and right slide bodies 123, 124, the swing arms 152, 153, the swing links 154,
155 are linked, and the left and right guide bodies 150, 151
Rotated around 49.

Then, the rotor support arms 159, 160, arm support shafts 165, 166, and left and right rotors 157, 158
The operation arms 161 and 162 are inclined as shown in FIG.

In this case, the left and right traveling hydraulic motors ML, MR
The right and left swash plates (not shown) for controlling the vehicle have the same inclination angle, the left and right traveling units 1L and 1R advance forward at the same speed, respectively, and the aircraft goes straight.

Next, when the steering wheel 36 is turned leftward by turning the handle 36 leftward from the straight traveling state, the steering operation shaft 120 is rotated, and the rack 136 meshing with the pinion gear 137 is moved rightward. The moving body 125 together with the rack 136 pulls and moves the left slide body 123 to the right.

The left guide body 150 is a slide body.
The guide body 150 is moved to the right together with 123, and the guide body 150 is slid to the right while maintaining the inclined posture. On this occasion,
The rotor 157 fitted to the left guide 150 is shown in FIG.
As shown in FIG.
Is located in the approximate center.

Accordingly, the left rotor supporting arm 159 and the operating arm 161 are rotated to approach a horizontal posture, and the left inclined control arm for controlling the left traveling hydraulic motor ML via the direct connection link 126 and the pump operation lever 128. Bring the plate (not shown) closer to the neutral state.

In this case, since the speed of the left traveling unit 1L is reduced or stopped and the right traveling unit 1R maintains the previous speed, the aircraft slowly turns left.

Next, in the left turning state, the steering wheel
When the rotation of the 36 is further performed in the left turning direction, the left guide body 150 is further slid to the right while maintaining the inclined posture. At this time, as shown in FIG. 20, the left rotor 157 is moved to the left portion of the guide body 150, and the rotor support arm 159 and the operating arm 161 are inclined right down. Lean the left swash plate to the reverse control side.

In this case, the left traveling unit 1L travels backward, while the right traveling unit 1R travels forward, so that the aircraft makes a spin turn to the left.

Next, the hydraulic circuit K will be described with reference to FIG. That is, the hydraulic circuit K has an HST hydraulic circuit 190 connected to the hydraulic tank T, and the HST hydraulic circuit 190 has a hydraulic circuit 191 for driving the left traveling unit and a hydraulic circuit 192 for driving the right traveling unit.
And are connected respectively.

The HST hydraulic circuit 190 is provided with a pair of variable flow control pumps PL and PR.
Hydraulic pump P1 for work equipment lift is linked and connected to PL and PR,
The work equipment lifting hydraulic pump 193 is connected to the work equipment lifting hydraulic circuit 193.

The variable flow rate control pumps PL and PR are linked to a charge pump P2, and the charge pump P2 is connected to pilot oil passages 235 provided with brake devices 195 and 196 provided in hydraulic circuits 191 and 192 for driving the left and right traveling units, respectively. The pilot oil passage switching valve 194 is mounted in the middle of the pilot oil passage 235. 197 is a bypass operation switching valve.

The pilot oil passage switching valve 194 is interlocked with the brake pedal 40, and the pilot oil passage switching valve 194 is switched in conjunction with the depression operation of the brake pedal 40, and the brake devices 195 and 196 are operated. It is configured to brake.

That is, in the brake devices 195 and 196, piston rods 195c and 196c urged in the extending direction by springs 195b and 196b are provided in cylinders 195a and 196a, respectively. 1
Attach 96d, and attach each pressure contact body 195d, 196d to each running part 1L, 1R
Brake equipment 195e, 196 mounted on drive wheels 10L, 10R
e can be moved freely.

By supplying the pilot oil into each of the cylinders 195a and 196a in this manner, the spring 195
The piston rods 195c and 196c are shortened against the urging of the b.
5c, 196e It is possible to make the non-brake operation state by separating from the state.

By discharging the pilot oil from the cylinders 195a and 196a, the piston rods 195c and 196c are extended by the urging force of the springs 195b and 196b, and the press-contact members 195d and 196d are moved to the brake device main body 195e and 196e. At 196e, it can be brought into pressure contact with the brakes.

Accordingly, by depressing the brake pedal 40, the driving of the left and right traveling units 1L, 1R can be stopped simultaneously by the left and right brake devices 195, 196, and even in an emergency, the same depressing operation feeling as that of a car can be obtained. Brake depression operation can be performed, and safety can be ensured well.

In the middle of the pilot oil passage 235,
As shown in FIG. 21, a branch pilot oil passage 237 is connected via a pilot oil passage switching valve 194. The branch pilot oil passage 237 has a bifurcated tip to form branch oil passages 237a and 237b, while the pair of variable flow control pumps PL and PR have swash plate angle control means 236L and 236L, respectively.
R, and the swash plate angle control means 236L and 236R
237a and 237b are connected.

[0136]

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

According to the first aspect of the present invention, a steering operation angle detecting means for detecting a steering operation angle of the steering operation means, a shift operation angle detecting means for detecting a shift operation angle of the shift operation means, and a vehicle speed Vehicle speed detecting means for detecting the brake braking operation, brake braking operation detecting means for detecting the braking operation of the brake braking operation means, and swash plate angle control members for controlling the swash plate angles of the pair of variable flow control pumps. A pair of electric actuation means connected to the input side and a control means connecting the pair of electric actuation means to the output side. Based on the detection result by the operation detection means,
A first operating area in which the reduction ratio of each traveling hydraulic motor is increased through the pair of electric operating means by the control means, and a pair of electric operating means by the control means based on a detection result by the brake braking operation detecting means. Since the brake device has a second operation region for reducing the discharge amount of each variable flow control pump through the third operation region and a third operation region in which the brake device brakes the drive wheels, By sequentially operating the operation area → the second operation area → the third operation area, the machine body can be gently stopped, and the impact force to the operator at the time of stop can be eliminated.

[0138] Therefore, the operator may be scared,
It is possible to prevent the operator from being injured.

According to the second aspect of the present invention, since the brake-braking release operation by the brake-braking operation means is performed through the third operation area → the second operation area → the first operation area, the aircraft always starts at a low speed. Is done.

Therefore, it is possible to prevent the operator from feeling terrified or causing an accident due to the rapid start.

[Brief description of the drawings]

FIG. 1 is a side view of an agricultural tractor as a hydraulic traveling agricultural working machine according to the present invention.

FIG. 2 is a plan view of the agricultural tractor.

FIG. 3 is a front view of the agricultural tractor.

FIG. 4 is an explanatory plan view of a driving unit.

FIG. 5 is a side view of the operation unit.

FIG. 6 is a plan view of the operation unit.

FIG. 7 is a control explanatory diagram.

FIG. 8 is an explanatory diagram of a braking operation of a brake pedal.

FIG. 9 is a rear view of the steering operation angle regulating unit.

FIG. 10 is an explanatory diagram of a regulating operation of the steering operation angle regulating means.

FIG. 11 is an explanatory diagram of a regulating operation of the steering operation angle regulating means.

FIG. 12 is a diagram illustrating a regulating operation of the steering operation angle regulating means.

FIG. 13 is an explanatory diagram of a regulating operation of the steering operation angle regulating means.

FIG. 14 is a sectional front view of a pump operation unit.

FIG. 15 is a cross-sectional plan view of the pump operation unit.

FIG. 16 is a sectional side view of the pump operation unit.

FIG. 17 is an explanatory plan view of a link operating arm in a neutral state.

FIG. 18 is an explanatory plan view of a link operating arm in a straight traveling state.

FIG. 19 is an explanatory plan view of the link operating arm in a left-turn state.

FIG. 20 is an explanatory plan view of a link operating arm in a left spin turn state.

FIG. 21 is a hydraulic circuit diagram.

[Explanation of symbols]

 A Agricultural tractor 1L Left running section 1R Right running section 2L Left running frame 2R Right running frame 3 Airframe 4 Engine section

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Katsumi Fujiki 428 Enami, Okayama City, Okayama Pref.

Claims (2)

[Claims] 1. A pair of traveling hydraulic motors are connected to a pair of variable flow control pumps interlocked to an engine via a closed circuit oil passage, and each traveling hydraulic motor is connected to a pair of left and right crawler traveling units. The driving wheels provided are interlocked and the variable flow control pumps are operated by the steering operation means and the speed change operation means to operate the traveling hydraulic motors to accelerate and decelerate the traveling parts on the left and right sides. Run each one,
The aircraft can be changed to any one of a straight running mode, a gentle turning mode, a pivot turn mode, and a spin turn mode, and the steering operation means includes a first steering operation range for setting a gentle turning mode, a pivot It has a second steering operation range for turning into a turn mode and a third steering operation range for turning into a spin turn mode, and a brake device provided on the drive wheel can be operated by a brake braking operation means. A steering operation angle detecting means for detecting a steering operation angle of the steering operation means, a shift operation angle detecting means for detecting a shift operation angle of the shift operation means, and a vehicle speed for detecting a vehicle speed. Detecting means; brake braking operation detecting means for detecting a brake braking operation of the brake braking operating means; A pair of electric operating means interlockingly connected to the member, and control means connecting the respective detecting means to an input side and connecting the pair of electric operating means to an output side; Means for increasing a reduction ratio of each traveling hydraulic motor through a pair of electric operating means by the control means based on a detection result by the brake braking operation detecting means; On the basis of the detection result, a second operation area in which the control means reduces the discharge amount of each variable flow control pump through a pair of electric operating means, and a third operation area in which the brake device brakes the driving wheels. A hydraulically driven agricultural work machine having: 2. The hydraulic traveling agricultural work machine according to claim 1, wherein the brake braking release operation by the brake braking operation means is performed through a third operation area → a second operation area → a first operation area.