JP2004340215A - Traveling vehicle - Google Patents

Abstract

In an agricultural vehicle, a differential device is driven in an appropriate power transmission mode according to a road surface by changing a differential limiting region of a differential device, and the differential device is adjusted so as not to be differential by adjusting the differential limiting region. To be configured.
A differential device (56) is provided for differentiating left and right front wheel axles (57R) for transmitting power to left and right front wheels in accordance with respective driving loads. A differential limiting device 61 is provided for limiting the relative rotational speed difference between the left and right front wheel axles 57R for transmitting power to the left and right front wheels. A changing means 62 for changing the differential limiting area of the differential limiting device 61 is provided, and the differential limiting device 61 is adjusted so that the differential device 56 does not make a differential by adjusting the changing means 62.
[Selection] Fig. 6

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power transmission mechanism in an agricultural traveling vehicle or the like.
[0002]
[Prior art]
In agricultural traveling vehicles such as rice transplanters, in order to prevent the front wheels from slipping when turning or when one wheel rides on the shore, a differential device with a clutch is provided in the front wheel drive system, and the left and right front wheels are Rotational power is transmitted to the left and right front wheels when grounded, and full rotational power is transmitted to the grounded side front wheel when one of the left and right front wheels is floating above the ground, ensuring sufficient thrust at all times There is known a technology that enables the use of such technology (for example, Patent Document 1).
[0003]
[Patent Document 1]
JP-A-6-135256 (pages 3 to 4, FIGS. 8 to 14)
[0004]
[Problems to be solved by the invention]
The conventional traveling vehicle equipped with the above-described differential device only selectively switches between a state in which the normal differential function works and a state in which the clutch is effective and the rotational power is transmitted to only one of the left and right front wheels. Met. In the case of agricultural traveling vehicles, road surface conditions, traveling speeds, and driving modes differ greatly between when working in the field and when traveling on the road, and even during work, conditions such as soil quality and the depth of the cultivator for each field vary. There is a difference. For this reason, the conventional traveling vehicle cannot always travel under an appropriate power transmission mode. Therefore, the present invention makes it possible to always run with an appropriate power transmission mode according to the road surface condition and running state, and to make it possible to adjust the differential device so as not to make a differential while simplifying the configuration. Is what you do.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention has taken the following technical measures.
The invention according to claim 1 is a differential that differentially drives left and right transmission shafts for transmitting power to the left and right traveling propulsion bodies in accordance with respective driving loads, and a relative rotation of the left and right transmission shafts. A differential limiting device for limiting a speed difference, changing means for changing a differential limiting region of the differential limiting device, and changing a differential limiting region of the differential limiting device so that the differential device does not make a differential. And changing means for performing the operation.
[0006]
According to the above configuration, the power from the prime mover is transmitted to the left and right transmission shafts via the differential device to drive the left and right traveling propulsion bodies. At this time, the relative rotational speed difference between the left and right transmission shafts is limited by the differential limiting device. Further, the differential limiting area of the differential limiting device can be changed by the changing means. Further, by adjusting the differential limiting device by the changing means, it is possible to change the differential device so as not to be differential.
[0007]
【The invention's effect】
According to the first aspect of the present invention, the relative rotation speed difference of the power transmitted to each of the left and right transmission shafts via the differential device is limited by the differential limiting device, so that the traveling propulsion body can be sufficiently driven. The driving propulsion can be prevented from slipping at the time of turning or when one of the propulsion propulsions rides on the shore by securing a proper propulsion force. In addition, by adjusting the differential limiting device by the changing means to change the differential device so as not to be differential, it is possible to cope with extreme deterioration of the road surface condition, and it is not necessary to separately provide a differential lock device. The structure can be simplified well.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention shown in the drawings will be described.
1 and 2 are an overall side view and a plan view of a fertilizer rice transplanter equipped with a traveling vehicle according to the present invention. The fertilizer application planter 1 is provided with a five-row seedling planting section 4 that can be moved up and down behind a traveling vehicle body 2 via an elevating link device 3. Part is provided. On the left and right sides of the front part of the traveling vehicle 2, two sets of spare seedling frames 6 are provided on each side. The seedling planting section 4 and the fertilizer applicator 5 have a known configuration, and a description thereof will be omitted.
[0009]
The traveling vehicle 2 is a four-wheel drive vehicle including a pair of left and right front wheels 7, 7 and rear wheels 8, 8, which are traveling propulsion bodies, and is disposed at the front of the body as shown in FIG. Front wheel axle cases 11, 11 are laterally extended from both left and right side surfaces of the transmission case 10, and front wheels 7, 7 are rotatably supported by front wheel final cases 12, 12 which are provided to be able to turn at the front ends thereof. I have. The front ends of a pair of left and right main frames 13, 13 are fixed to the rear surface of the transmission case 10, and are fixed to the front ends of rear frames 14, which extend from the rear ends of the main frames 13, 13 to the left and right sides. Rear wheels 8, 8 are rotatably supported on the rear wheel final cases 15, 15 provided.
[0010]
An engine 20 is mounted above an intermediate portion of the main frames 13 and 13 in the front-rear direction. An upper portion of the engine 20 is covered with an engine cover 21, and a seat 22 is installed above the engine cover 21. A bonnet 23 having various built-in operation mechanisms is arranged in front of the seat 22, and a steering handle 24 for operating the front wheels 7, which are steered wheels, is provided above the bonnet 23. Steps 25 are provided around the engine cover 21 and the hood 23 for a person to move or work.
[0011]
The various operating devices include a shift lever 30, an auxiliary shift lever 31, a planting / elevating lever 32, a four-wheel brake pedal 35, a four-wheel brake lever 34, left and right rear wheel brake pedals 35L and 35R, a differential lock lever. 36, a differential limiting load adjusting lever 37 is provided.
[0012]
Next, the power transmission mechanism of the traveling vehicle 2 will be described.
An engine output shaft 40 projects from the left side portion of the engine 20, and the rotational power of the engine output shaft 40 passes through a belt-type transmission 41 and a belt transmission 42 with a main clutch function, and the left side portion of the transmission case 10. The transmission is transmitted to the transmission input shaft 43 projecting from the transmission input shaft 43. A hydraulic pump 45 is provided on the extension of the engine output shaft 40 and outside the belt-type transmission 41, and the hydraulic pump 45 is directly driven by the rotational power of the engine output shaft 40. The shifting operation of the belt-type transmission 41 is performed by operating the shift lever 30 in the front-rear direction.
[0013]
FIG. 4 is a diagram showing the internal structure of the transmission case 10. The power input to the transmission input shaft 43 via the belt transmission 42 as a main clutch is transmitted to a subtransmission 50 having shift positions of “road running speed”, “normal planting speed”, “ultra low speed” and “neutral”. Is transmitted to the auxiliary transmission shaft 51 via the The sub-transmission 50 is shifted by the sub-transmission lever 31. A part of the rotational power of the auxiliary transmission shaft 51 is transmitted to the brake shaft 53 via the forward / reverse switching device 52 as running power. The forward / reverse switching device 52 switches between “forward” for transmitting reverse power from the auxiliary transmission shaft 51 to the brake shaft 53, “reverse” for transmitting power in the same direction, and “PTO” for not transmitting power. Has become. The shift change of the forward / reverse switching device 52 is performed by operating the shift lever 30 in the left-right direction. The brake shaft 53 is provided with a four-wheel brake device 55 that can be operated by operating the four-wheel brake pedal 33 or the four-wheel brake lever 34.
[0014]
The rotational power of the brake shaft 53 is distributed and transmitted to the front wheel axles 57L, 57R, which are transmission shafts that are transmitted to the traveling propulsion body, by the differential device 56, and further transmitted to the front wheel final cases 12, 12 by the front wheel axles 57L, 57R. The power is transmitted to drive the front wheels 7,7. Further, it is taken out from the rear part of the transmission case 10 via the cylindrical shafts 58L, 58R which mesh with the case of the differential device 56 rotatably fitted to the outer peripheral parts of the front wheel axles 57L, 57R, and are taken out of the rear wheel transmission shaft. The transmission is transmitted to the rear wheel final cases 15, 15 via 59, 59, and the rear wheels 8, 8 are driven.
[0015]
A differential lock device 60 for stopping the differential function of the differential device 56 is provided on the left front wheel axle 57L. The differential lock device 60 includes a sliding body 60a that rotates integrally with the front wheel axle 57L and is slidable in the axial direction. The sliding body 60a is slid by a rotary differential lock pin 60b to form a cylindrical shaft 58L. By meshing, the differential function of the differential device 56 is stopped (differential lock device ON), and the rotational speeds of the left and right front wheel axles 57L, 57R are made equal. The differential lock device 60 is operated by the differential lock lever 36.
[0016]
The right front wheel axle 57R is provided with a differential limiting device 61 for limiting the relative rotational speed difference between the left and right front wheel axles by the differential device 56 as shown in FIG. The differential limiting device 61 presses the disk 61b attached to the shaft cylinder 58a against the plate 61a on the front wheel axle 57R side by the elastic force of the disc spring 61c. As a result, the front wheel axle 57R and the cylinder shaft 58R rotate integrally until the rotational speed difference between the left and right front wheel axles 57L and 57R exceeds a certain value, and the differential lock device 60 is turned on. , The function of the differential 56 stops. When the rotation speed difference exceeds a certain value, the disc 61b is pushed back from the plate 61a against the elastic force of the disc spring 61c, and the axle 57R and the cylinder shaft 58R rotate separately, so that The differential 56 becomes functional.
[0017]
The spring force of the disc spring 61c can be changed by shifting the position of the end face of the disc spring 61c opposite to the disk 61b by the rotating differential limiting load changing pin 62 which is a changing means. When the elastic force of the disc spring 61c is increased, the differential limiting area by the differential limiting device 61 is narrowed, and the rotational speed difference between the left and right front wheel axles 57L, 57R does not increase more than a certain value. Conversely, when the elastic force of the disc spring 61c is weakened, the differential limiting area is widened, and the difference between the rotational speeds of the left and right front wheel axles 57L, 57R can be increased. The differential limiting load changing pin 62 is operated by the differential limiting load adjusting lever 37.
[0018]
The left and right cylinder shafts 58L and 58R are disengaged from the case of the differential device 56 to cut off transmission to the rear wheel drive system, and to brake the rear wheel drive system by a rear wheel clutch / brake device 63L. , 63R are provided. The rear wheel clutch / brake devices 63L and 63R are separately operated by rear wheel brake pedals 35L and 35R, respectively.
[0019]
The remainder of the rotational power of the auxiliary transmission shaft 51 is transmitted to the PTO output shaft 67 via a pair of auxiliary transmission gears 65 and 66 as rotational power for driving the work implement. A PTO transmission shaft 68 is connected to a rear end of the PTO output shaft 67, and PTO power is transmitted to the planting clutch case 69 via the PTO transmission shaft 68. Then, the power is transmitted from the planting clutch case 69 to the seedling planting section 4 and the fertilizer application device 5.
[0020]
Since the power transmission mechanism of the traveling vehicle is configured as described above, by operating the differential limiting load adjusting lever 37 to change the differential limiting area in accordance with the road surface condition and the traveling speed, the road limiting surface is always maintained. Alternatively, an appropriate power transmission mode suitable for the conditions of the field and the traveling speed can be obtained. Specifically, when the differential limiting area is widened when turning the aircraft, the power is appropriately distributed and transmitted to the front wheel axle 57L (57R) inside the turning and the front wheel axle 57R (47L) outside the turning. And the cornering can be stabilized. Further, if the differential limiting area is widened when the road surface is soft, the power is appropriately distributed and transmitted to the left and right front wheel axles 57L, 57R according to the driving load, so that the front wheels 7, 7 are prevented from slipping. While stable running is possible. Furthermore, if the differential limiting area is widened when the steering wheel 24 is turned sharply, it is possible to perform a proper turning according to the turning radius. Further, when the vehicle is traveling at a high speed, such as when traveling on a road, and narrowing the differential limiting region, the straightness is increased and traveling can be stabilized.
[0021]
Next, another embodiment of the differential limiting device 61 will be described with reference to FIG.
The resilient force of the disc spring 61c is shifted by shifting the position of the end face of the disc spring 61c on the side opposite to the disk 61b by the rotating differential limit load changing pin 62, which is a means for changing the differential limit load of the differential limiter 61. In order to change the differential limiting load change pin 62 to the position A, the elastic force of the disc spring 61c is adjusted to a predetermined elastic force to adjust the differential limiting area of the differential limiting device 61, Alternatively, the differential limit load change pin 62 is further operated to the position B, and the disc spring 61c is pressed to differentially move the plate 61a on the front wheel axle 57R side and the disk 61b on the cylinder shaft 58R so as not to slip even when overloaded. It is configured so that it can be changed to the locked state.
[0022]
Thus, by limiting the relative rotational speed difference of the power transmitted to the left and right front wheel axles 57L, 57R via the differential device 56 by the differential limiting device 61, a sufficient propulsive force of the traveling wheels is secured. By changing the differential limiting device 61 to the differential lock state while smoothly turning, when one of the traveling wheels rides on the shore or when the condition of the road surface becomes extremely bad, Also, the traveling wheels can be prevented from slipping and traveling smoothly. Further, by setting the differential limiting device 61 in the locked state, the differential limiting device 61 can also serve as a differential lock device, and the configuration can be simplified.
[0023]
Next, a control device of the differential limiting device 61 will be described with reference to FIG.
The input side of the controller 71 is connected to a sub-shift lever sensor 72 via an input interface, and the output side of the controller 71 is connected to a differential lock lever driving means 73 via an output interface.
[0024]
When the sub-transmission lever sensor 72 detects that the sub-transmission lever 31 has been operated to the low-speed transmission region at the “planting speed” position or the “ultra low speed” position, the difference from the controller 71 is detected. When the dynamic lock command is issued, the differential lock lever driving means 73 is operated, and the differential lock lever 36 is operated to the entrance side, so that the differential lock device 60 is locked.
[0025]
When the sub-transmission lever sensor 72 detects that the sub-transmission lever 31 has been operated in the high-speed transmission region at the “road running speed” position, a differential lock release command is issued from the controller 71 and the differential lock lever driving means 73 is output. Is released, the differential lock lever 36 returns to the cut side, and the differential lock device 60 is released.
[0026]
In the low speed shift state, the differential lock device 60 in the traveling transmission path is in the engaged state, and in the high speed shift state, the differential lock device 60 is released. Even if the gears are shifted to the gear change state, the vehicle does not travel at high speed in the locked state of the differential lock device 60, and the traveling can be stabilized while facilitating the operation.
[0027]
Note that, instead of turning on / off the differential lock device 60, the differential limiting area of the differential limiting device 61 is changed by changing means to switch the differential device 56 to the differential limiting region, May be configured to switch to a differential lock state where no differential is applied.
Next, another embodiment of the steering device of the fertilizer rice transplanter 1 will be described with reference to FIG.
[0028]
In this embodiment, a left and right inclination sensor 74 for detecting the left and right inclination is provided on the traveling body 2 of the fertilizer rice transplanter 1, and when the left and right inclination sensor 74 detects a left or right inclination equal to or more than a predetermined value, the steering motor 75 is activated. Then, the left and right front wheels 7, 7, which are the steered wheels, are steered by a predetermined angle to the higher inclined side to prevent the vehicle from turning to the lower inclined side and to move the traveling vehicle body 2 straight.
[0029]
Steering rods 77, 77 for steering the left and right front wheels 7, 7 are connected to the tip of the pitman arm 76 that rotates left and right, and the steering means 78 is connected to the tip of the pitman arm 76. The steering means 78 has left and right steering wires 78b, 78b connected to the pitman arm 76 so as to be able to be pushed and pulled via springs 78a, 78a, and the other ends of the left and right steering wires 78b, 78b. And a pinion 78d for driving the rack 78c, and the steering motor 75 drives the pinion 78d. The input side of the controller 71 is connected to a left / right tilt sensor 74 via an input interface, and the output side of the controller 71 is connected to a steering motor 75 via an output interface.
[0030]
Thus, when the left-right inclination sensor 74 detects the leftward or rightward inclination that is equal to or more than the predetermined angle, the controller 71 issues a command to perform a predetermined angle steering to the higher inclination side, the steering motor 75 is operated, and the left and right front wheels 7, 7 are moved. Control is performed such that the steering wheel is steered by a predetermined angle to the higher tilt side. Therefore, the traveling vehicle body can be made to travel straight even on a slope, and the steering wheel operation becomes easy. If the operator operates the steering handle 24 with his / her intention, the pitman arm 76 can be operated and steered against the springs 78a and 78a. It is difficult to make the vehicle travel straight on an inclined ground only by operating the conventional steering handle 24.
[0031]
Next, the operation control of the fertilizer rice transplanter 1 will be described with reference to FIGS.
On the input side of the controller 71, a memory start switch 79, a memory stop switch 80, a lateral movement amount detection sensor 82 for detecting the lateral movement amount of the seedling tank 81, and a steering state of the front wheels 7, 7 via an input interface. A steering sensor 83 and a vehicle speed sensor 94 are connected, and on the output side of the controller 71, a control motor 84 for turning on / off the power of the seedling planting section 4 via an output interface, and an elevating cylinder for elevating the elevating link device 3 Driving means 85 is connected.
[0032]
A seedling tank 81 is supported on the seedling mounting table 86 of the seedling mounting section 4 via an upper rail 87 and a lower rail (not shown) so as to be reciprocally movable in the horizontal direction. A detection sensor 82 is provided. Thus, when the seedling tank 81 reciprocates and moves laterally while making contact with the upper rail 87, the lateral movement amount detection sensor 82 rotates, and the lateral movement amount of the seedling tank 81 can be detected.
[0033]
When the fertilizer application planter 1 travels along the shore in the rectangular field 88 to perform seedling planting operation, the seedling planting operation is started in the first step A at the beginning of planting of the seedling planting device (not shown). At the time, the memory start switch 79 is turned on to start detecting the lateral movement amount of the seedling tank 81, and at the end of the seedling planting operation of the first process A, the memory stop switch 80 is turned on, and the lateral movement amount detection sensor 82 The amount of lateral movement of the seedling tank 81 in the first step is detected and stored in the storage unit of the controller 71.
[0034]
At the start of the seedling planting operation in the first step, the control motor 84 is manually operated to transmit power to the seedling planting section 4, and at the end of the first step seedling planting operation, the control motor 84 is manually operated. The drive of the seedling planting section 4 is stopped, and the steering handle 24 is operated to turn the fertilizer planting machine 1.
[0035]
Next, when the steering sensor 83 detects that the turning of the first stroke A of the fertilizer rice transplanter 1 has been completed, the seedling planting operation of the second stroke B is started after traveling a predetermined distance. At the start of the operation of the seedling planting section in the second step B, the control motor 84 is operated by a command from the controller 71 to drive the seedling planting section 4 and the lateral movement amount detection sensor 82 moves the seedling tank 81 laterally. Start detecting the amount. Next, when the lateral movement amount detection sensor 82 detects the end of the movement of the lateral movement distance detected and stored in the first stroke of the seedling tank 81, the control motor 84 is driven by a control command from the controller 71, and the seedling placement section 4 is driven. Stop driving. Next, when the turning of the fertilizer rice transplanter 1 is started by operating the steering handle 24, a command of the controller 71 is issued based on the detection information of the steering sensor 83, and the lifting / lowering cylinder driving means 85 operates to raise the lifting / lowering link device 3. When the steering sensor 83 detects that the turning of the fertilizer planting machine 1 has been completed and the vehicle travels a predetermined distance, the seedling planting operation in the third step is started. Note that the same control as in the second stroke B is performed after the third stroke.
[0036]
In the prior art, each time the seedling planting process is completed, it is necessary for the operator to manually operate the control motor 84 or operate the lever to stop the drive of the seedling planting apparatus. However, there was a problem that it became complicated.
However, in this embodiment, since the configuration is as described above, the memory start switch 79 and the memory stop switch 80 are operated only in the first stroke A, and the control motor 84 is manually operated to control the seedling planting section 4. It is necessary to drive and stop, but after the second stroke B, the driving and stopping of the seedling planting section 4 can be performed automatically, and the turning operation can be simplified.
[0037]
Next, another embodiment of the seat 22 and the step 25 will be described with reference to FIGS.
The upper body 89 is composed of, for example, a synthetic resin material by integrating the step portion 89a, the engine cover portion 89b, and the seat portion 89c, a cushion material 90 is attached to the seat portion 89c, and a backrest portion 89d is integrated with the seat portion 89a. This is a configuration or a configuration in which a separately configured backrest 89d is attached.
[0038]
The backrest 89b is hollowed out to form a tool holder 91. The upper part of the backrest 89d is covered with a lid 92 and is locked with a locking member 93.
With the above-described configuration, the step portion 89a, the engine cover portion 89b, and the seat 89c can be integrated to reduce costs, and the tool holder 91 is formed in the backrest portion 89d of the seat portion 89c. It becomes convenient.
[Brief description of the drawings]
FIG. 1 is a side view of the whole. FIG. 2 is a plan view of the whole. FIG. 3 is a plan view of a main part. FIG. 4 is a cut-away plan view of a main part. FIG. FIG. 7 is a control block diagram. FIG. 8 is a plan view of a main part. FIG. 9 is a plan view of a field. FIG. 10 is a side view and a front view of a main part. FIG. 11 is a control block diagram of FIG. Side view and front view of main parts [FIG. 13] Top view of main parts [FIG. 14] Perspective view of main parts [Explanation of reference numerals]
DESCRIPTION OF SYMBOLS 1 Fertilizer application planting machine 7 Left and right front wheels 8 Left and right rear wheels 37 Differential limit load adjustment lever 56 Differential device 57R Right front wheel axle 61 Differential limit device 61a Plate 61b Disk 61c Belleville spring 62 Differential limit load change pin (change means)

Claims (1)

A differential device for differentially driving the left and right transmission shafts for transmitting power to the left and right traveling propulsion bodies in accordance with respective driving loads, and a differential for limiting a relative rotational speed difference between the left and right transmission shafts. A limiting device, changing means for changing a differential limiting region of the differential limiting device, and changing means for changing a differential limiting region of the differential limiting device so that the differential device does not make a differential. A traveling vehicle, characterized in that:

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