JP2009029210A - Tread adjustment control device of working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein a sensor value is not changed up to a tread width set in advance within a stroke time corresponding to a tread change output when adjusting a tread, in other words, the tread can not be adjusted up to the set width. <P>SOLUTION: This tread adjustment control device is provided with hydraulic cylinders changing and adjusting the treads of right and left wheels journaled on a vehicle. The hydraulic cylinders are connected to hydraulic valves for supplying hydraulic fluid based on hydraulic cylinder signals. The hydraulic cylinders are provided with each stroke sensor to measure changes of the treads. When measured values of the stroke sensors corresponding to the tread change outputs can not be obtained after supplying the hydraulic fluid to the hydraulic cylinders by the hydraulic valves and performing tread change outputs, controls to stop the tread change outputs are made possible after a positive correction time added to the normal stroke time by the tread change outputs. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a tread adjustment control device for a work vehicle such as an agricultural tractor, a riding management machine, or an aerial work vehicle.

  2. Description of the Related Art Conventionally, a technique for changing and adjusting a tread of a wheel pivoted on a vehicle is widely known, for example, as disclosed in Japanese Patent Application Laid-Open No. 2000-301906 (see Patent Document 1). In addition, there is a known technique filed by the present applicant.

  A tread changing device for a work vehicle described in the publication includes a hydraulic cylinder that changes a tread of a front wheel or a rear wheel of the vehicle, and a stroke sensor that detects the tread, and the front wheel when the engine of the vehicle is started, Alternatively, when it is detected that the tread of the rear wheel is in the changed state, the left and right rear wheels are operated until the on / off switch for changing the tread is changed from [On] to [Off] and from [Off] to [On]. The brake is activated to temporarily check the start of the vehicle.

As described above, the known technique is a technical means for ensuring the safety of the subsequent traveling accompanying the change of the tread.
JP 2000-301906 A

  Normally, when adjusting the tread between the left and right wheels in the tractor, the operator uses the tread width setting dial to preset the tread width to be adjusted and input it to the controller, and then turn on the tread adjustment set switch. By operating, tread adjustment control is started. The controller then controls the hydraulic valve based on the tread change output that is output as a control signal, and adjusts the tread while supplying hydraulic oil to the hydraulic cylinder. At that time, it responds to the tread change output for some reason. In some cases, the detection value of the stroke sensor is not obtained.

  In such a case, conventionally, when the operator knows that there is no change in the sensor value as described above, the tread change output is stopped immediately, or after the normal stroke time corresponding to the tread change output elapses. Since the change output was stopped, there was a problem that the tread adjustment of the wheel could not be adjusted to a preset tread width.

  In general, tread adjustments for tractors, etc. are performed by treading to the tread width set within the normal stroke time corresponding to the tread change output when the weight of the work equipment connected to the vehicle body, especially the weight of the work equipment is loaded on the load. In many cases, it cannot be changed, and a normal stroke time + α is required, and α must be set according to the weight of the work implement (corresponding to the load).

  In order to solve the above-mentioned problems, the present invention provides a hydraulic cylinder (3, 3) that changes and adjusts the tread of the left and right wheels (2, 2) that are pivotally mounted on the vehicle (1). 3), and the hydraulic cylinder (3, 3) is connected to a hydraulic valve (4, 4) for supplying hydraulic oil based on a control signal. The hydraulic cylinder (3, 3) has a stroke sensor, respectively. (5, 5) is provided so that changes in the tread can be measured, and hydraulic oil is supplied to the hydraulic cylinders (3, 3) by the hydraulic valves (4, 4) to perform a predetermined tread change output. After that, when the measurement value of the stroke sensor (5, 5) corresponding to the tread change output is not obtained, a predetermined correction time (α) is added to the normal stroke time (T) by the tread change output. Before time passes It is obtained by a tread regulatory control device for a working vehicle which constitutes the controller (22) to stop the tread changes output.

When adjusting the tread of the left and right wheels pivoted on the vehicle, the correction time α is set, and the normal stroke time corresponding to the tread change output is set in the controller and output.
The invention described in claim 2 is a tread adjustment control device for a work vehicle according to claim 1, wherein the correction time (α) is set longer when the weight of the vehicle (1) increases. is there.

  The correction time α is set according to the weight of the vehicle body, and the normal stroke time plus the correction time α corresponding to the tread change output (T + α) is set in the controller (22) and output.

  First, according to the invention described in the claims, in setting the time at the time of stroke operation in the controller 22, the time (T + α) is set by adding the correction time α to the normal stroke time T corresponding to the tread change output, By configuring the control to stop the tread change output after a lapse of time, even if the left and right wheels are temporarily in contact with an obstacle during the tread change, for example, the correct tread is output by continuing the change output for the correction time α. It becomes possible to become a position.

  According to the second aspect of the present invention, when the vehicle weight increases, the correction time α to be added is lengthened. Therefore, the tread adjustment of the wheel can be adjusted in advance without depending on the vehicle weight. You can adjust to the width.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a tread adjustment control apparatus equipped with an agricultural tractor shown in the drawings will be described in detail below.
First, as shown in FIGS. 4 and 5, the tractor 7 has an engine 9 mounted in a front bonnet 8, and a clutch housing and a gear-type transmission that houses a main clutch at the rear of the engine 9. The mission case 10 to be connected is integrally connected. A tread-adjustable rear axle case 11 is provided on both the left and right sides of the mission case 10, and wheels 2 and 2 are provided on the ends of the case 11 on both the left and right sides.

Further, a front axle case is provided below the engine 9 so as to be able to roll around a front and rear axis, and front wheels 12 and 12 are provided to be steerable on both side ends.
The cockpit 13 is provided in a cabin 14 mounted on the vehicle body 1, and has a configuration in which an operation panel 15, a display panel 16, a steering handle 17, and operation levers are concentrated in the front. Yes. Reference numeral 18 denotes a cover of the display panel 16. As shown in FIG. 1, the operation panel 15 is provided with various setting devices such as a tread adjustment set switch 20 and a tread width setting dial 21 and a controller serving as a control unit below the cockpit 13. 22 is input.

  In FIG. 4, a cylinder case 24 having a hydraulic cylinder for raising and lowering the work implement is provided at the upper rear portion of the mission case 10. The lift arm 25 is configured to move up and down by expanding and contracting the piston of the hydraulic cylinder in the cylinder case 24, and to move up and down the rear rotary tiller 26 connected thereto. One of the lift arms 25 is provided with a potentiometer-type lift arm angle sensor for detecting the height of the work implement, and the detection position of the potentiometer of the work implement lift lever and the rotation setting position of the lift arm 25 are as follows. The switching control valve for raising or lowering the work implement in the hydraulic circuit is switched by a control signal from the controller for raising / lowering control so as to match.

Next, the tread adjustment control device will be described.
First, in FIG. 3, drive shafts 29, 29 extending from the rear wheel differential mechanism 28 disposed at the center to the left and right sides are respectively connected to the left and right transmission cylinders via brake devices 30, 30 and speed reducers 31, 31. The driving power reaching 32 and 32 is transmitted. As shown in the drawing, the left and right wheels 2 and 2 are pivotally attached to the wheel shafts 33 and 33, respectively, and the wheel shafts 33 and 33 are supported by the wheel support cases 34 and 34. It has become.

  As shown in FIG. 3, the wheel shafts 33, 33 are arranged such that the wheels 2, 2 at the tip (outer side) are left and right with respect to the transmission cylinders 32, 32 supported rotatably on the vehicle 1 side. The rear wheel differential mechanism 28 is configured so that the traveling power can be transmitted from the rear wheel differential mechanism 28 to the wheels 2 and 2. The tread adjusting hydraulic cylinders 3 and 3 fix the cylinder lot 35 to the housing case 36 (on the transmission cylinder 32 side), and are provided between the transmission cylinders 32 and 32 and the wheel support cases 34 and 34. It consists of a left chamber 3L and a cylinder right chamber 3R, and is configured such that the tread can be adjusted by an expansion / contraction operation between the chambers 3L and 3R.

For the sake of clarity, the hydraulic cylinders 3 and 3 of the embodiment shown in FIG. 3 are shown for convenience, with the left side in a contracted state and the right side in an expanded state.
As shown in FIG. 3, the left and right hydraulic valves 4 and 4 are connected to oil tanks (hydraulic pumps) and the chambers 3L and 3R on the hydraulic cylinders 3 and 3 side by piping, respectively. Oil is used to supply hydraulic oil and expand and contract.

  As shown in FIG. 3, the stroke sensors 5, 5 are attached at positions where the expansion / contraction stroke can be measured along the hydraulic cylinders 3, 3, and the measured values are input to the controller 22. In FIG. 1, reference numeral 37 denotes an input shaft rotation sensor that detects the rotation of the wheels 2 and 2.

  As shown in FIG. 1, the controller 22 connects the tread width setting dial 21 of the operation panel 15, the stroke sensors 5 and 5 and the rotation sensor 37 on the input side, and the output side on the output side. The hydraulic valves 4 and 4 are connected to the display panel 18. When the tread change output is output from the controller 22 and tread adjustment is performed, the display panel 18 displays (A) shown in FIG. 2, and as the tread adjustment control proceeds, the stroke sensor 5 is displayed. , 5 is configured to display the change in the detected value measured schematically as shown in (B).

  The tread control based on the tread change output of the controller 22 is a stroke time corresponding to the tread change output when the load is weighted by the weight of a work machine (in the embodiment, the rotary tiller 26 in the embodiment) connected to the vehicle 1. It is assumed that there is no change in the sensor value up to a preset tread width, in other words, the tread adjustment cannot be made up to the set width. Therefore, the controller 22 sets a plus α time corresponding to the weight of the work machine 26 connected to the vehicle 1. With this setting, when the measured values of the stroke sensors 5 and 5 cannot be obtained within the normal stroke time corresponding to the tread change output, the controller 22 adds to the normal stroke time (T) by the tread change output. It becomes possible to perform control to stop the tread change output after the time α (T + α).

  The tread adjustment control device configured as described above is controlled by the controller 22 shown in FIG. 1, and a tread width to be adjusted is set in advance by the tread width setting dial 21, and then the tread adjustment set switch 20 is turned on. Can be done.

  Then, the hydraulic cylinders 3 and 3 perform the tread changing operation while the high pressure hydraulic oil is supplied in a state where the relief is effective, and when the output operation is finished, the internal pressure remains in the cylinders 3 and 3 next time. Wait until the tread change operation. Then, the internal pressure remaining in the hydraulic cylinders 3 and 3 gradually increases with time, and when the oil temperature rises in relation to the ambient temperature, the pressure is further influenced by the internal pressure. Will be higher. As a result, the hydraulic cylinders 3 and 3 have a problem that there is a risk that the internal pressure is applied to the pipes in the communication state, resulting in breakage or the like.

  Therefore, in the case of the embodiment, after the hydraulic valves 4 and 4 supply the hydraulic oil to the hydraulic cylinders 3 and 3 to adjust the tread of the left and right wheels 2 and 2, the tread change on the opposite side to the tread change output is performed. Provide a means to output the output for the set time (T), reduce the internal pressure remaining in the cylinder, prevent the ripple to the surrounding piping in communication, and protect it safely. Yes.

  As described above, in the case of the embodiment, when the hydraulic valves 4 and 4 supply the hydraulic oil to the hydraulic cylinders 3 and 3 to perform the tread change output and the tread adjustment is finished, The tread change output on the opposite side (opposite direction) to the direction of the tread change output is executed for a set time. At this time, in the embodiment, on the expansion side and the contraction side of the hydraulic cylinders 3 and 3 Since the inner areas of the cylinders are different, for example, the output is an extremely short time such as “T = 80 msec,” but the output is made with a time difference according to the area difference.

  As described above, the embodiment of the present invention assumes a weighted load generated by the weight of the work implement 26 when the tread changing operation of the wheels 2 and 2 is performed in setting the waiting time during the stroke operation in the controller 22. The correction time α is set, and the total waiting time (T + α) is set in the controller 22 in addition to the normal stroke time (T) corresponding to the tread change output. Therefore, the controller 22 controls the tread adjustment control of the wheels 2 and 2 to the tread width set in advance by the tread width setting dial 21 without depending on the type (weight) of the work equipment 26 connected to the vehicle 1. It can be adjusted.

Next, an embodiment regarding the attachment of the front fender 40 and the cutting angle stopper 55 of the front wheels 12 and 12 will be described.
Conventionally, the tractor rarely attaches the front fender 40 to the front wheels 12, 12, and the safety of the front wheels 12, 12 at the time of traveling and the scattering of mud to the surroundings are problems, and the attachment of the fender is desired.

Examples will be described below with reference to FIGS.
First, the mounting bracket 41 of the front fender 40 is connected and supported in a state straddling the final case 42 for attaching the front wheels 12 and 12 and the connecting portion of the knuckle arm 43, and the fender support 44 is placed on the upper side. Are connected and fixed. As shown in FIGS. 7 and 8, the fender 40 is connected to the upper side sequentially from the lower first fixture 45 to constitute the fender support 44. The fixture 46 is connected, this is made into a front view (or rear view) L shape, the 3rd fixture 47 is integrally formed, and it is set as the structure which attached the fender 40 to the upper position of this. The mounting bracket 41 according to the embodiment is provided by tightening the mounting bolts together to secure the mounting strength, and does not interfere with the surroundings even if the steering wheel is steered together with the front wheels 12 and 12 in accordance with the steering operation. It has a configuration.

  As shown in FIG. 8, in the fender support 44, the first fixture 45 is provided with front and rear adjustment long holes 49 in two stages, and the second fixture 46 is provided with a vertical adjustment hole. 50, 50, 50 are provided in a plurality of stages, and the third fixture 47 is provided with left and right adjustment holes 51, 51, 51, which are connected to be adjustable in the front-rear direction, the up-down direction, and the left-right direction. The front fender 40 is attached to the three attachments 47.

  The fender support 44 configured as described above can be attached while adjusting the position to the left and right according to the tire size when the fender 40 is attached to the left and right adjustment holes 51, 51, 51 of the third attachment 47. . When the front fender 40 is attached to the fender support 44, the first attachment 45 is attached by adjusting the position back and forth using the upper and lower longitudinal adjustment holes 49, 49, and the second attachment. 46 is characterized in that it can be attached according to the tire size of the front wheels 12 and 12 while selecting the vertical position using a plurality of vertical adjustment holes 50, 50 and 50.

  Next, as shown in FIGS. 9 and 10, the cutting angle stopper 55 is disposed at a position away from the rotation center (steering axis at the time of steering operation) PP of the front wheels 12 and 12 for steering operation. Accordingly, the front wheels 12 and 12 are configured to have a stopper function that is steered and rotated around the rotation center PP. As shown in the drawing, the cutting angle stopper 55 is provided with a plurality of adjustment holes 57, 57, 57 on the base side of the attachment member 56 to adjust the attachment position of the attachment member 56, or A plurality of adjustment holes 58, 58, 58 are provided on the distal end side for adjustment.

  In this manner, the cutting angle stopper 55 can select and adjust the cutting angle of the front wheels 12 and 12 that are steered and rotated about the rotation center PP when steering is performed. There is an advantage that interference with the surroundings of the tractor can be prevented in advance.

  The cutting angle stopper 55 according to the embodiment is provided with a plurality of adjustment holes 57, 57, 57, or 58, 58, 58 on either the base side or the tip side of the mounting member 56, thereby cutting the front wheel. Since the angle range can be adjusted, there is a feature that a suitable cutting angle can be selected corresponding to the tread width.

Next, an embodiment of the breather 61 of the front axle 60 will be described with reference to FIGS.
First, as shown in the drawing, the breather 61 is provided with a through hole 63 in a battery mounting table 62 provided on the front axle 60, and passes through a breather pipe 61a communicating with the front axle 60 from the lower side to the upper side. And open to the open air.

  As shown in the drawing, the breather pipe 61a is formed long enough to prevent the oil in the front axle 60 from overflowing, and is configured not to be covered with mud and muddy water. As shown in the drawing, the through-hole 63 is formed in a laterally long hole so that it can cope with the swinging of the front axle 60.

  As shown in FIG. 13, the through-hole 63 is closed by a dust-proof cover 64 (in the embodiment, the rubber cover is provided with a cut so that the breather pipe 61a can swing left and right) to prevent dust from entering. It has a configuration that can be done.

  In the configuration example of FIG. 14, the breather 61 is welded and fixed to a tube 66 penetrating the bracket 65, a breather pipe 61 a is connected to the upper side, and a hose 67 attached to the front axle 60 is connected to the lower side. Configured.

By configuring in this way, the embodiment has a feature that it can sufficiently cope with the swing of the front axle 60 without being covered with mud.
Next, an embodiment of the brake switch device 69 will be described with reference to FIGS. 15 and 16.

  First, as shown in the drawing, the brake switch device 69 is provided as a sensor box 70 on the vehicle body side at a position corresponding to the middle of the brake pedal arm 71, and an operation bar in which the sensor arm 72 is provided integrally with the brake pedal arm 71. 73 is configured to be switched ON and OFF by 73. In this case, in FIG. 15, the sensor arm 72 is always configured to be tensioned by a spring toward the operation bar 73 (counterclockwise in FIG. 15) to maintain the pressure contact state, and the brake pedal 75 is depressed. When the brake pedal arm 71 is rotated, the operation bar 73 is also operated and moved integrally. At this time, the brake bar in the sensor box 70 is turned on by following and rotating in the tension state. Yes. In FIG. 16, the brake pedal 75 indicates a standby position, b a switch operating position, and c a brake effective start position.

This embodiment is characterized in that a rubber cover 76 is provided on the operation bar 73 and is always in contact with the sensor arm 72.
Thus, since the operation bar 73 according to the embodiment is configured to be covered with the rubber cover 76, wear caused by contact with the sensor arm 72 is greatly reduced, and the sensor arm that is always in a pressure contact state is reduced. The wear of 72 is also greatly reduced.

Next, a description will be given of an embodiment of a new operating mechanism in which the finger lever mechanism 81 is used together with the accelerator lever 80 and the conventional finger lever 83 (see FIG. 17) is eliminated.
First, as shown in FIG. 17, the conventional operating mechanism has a configuration in which two operating levers, that is, an accelerator lever 80 and a finger lever 83, are provided on one side of the operating lever box 82. It was the cause of mistakes.

  On the other hand, in the embodiment, as shown in FIGS. 18 and 19, one accelerator lever 80 is used and a finger gap mechanism 81 is used in combination with the lever. In this case, the accelerator lever 80 is configured such that the accelerator operation is possible in the lateral accelerator operation groove 84, and the vertical figup operation groove 85 is continuously formed at the terminal portion of the accelerator operation groove 84.

  In this way, as shown in FIG. 19, the accelerator lever 80 adjusts the increase / decrease in the amount of supply of engine fuel in the lateral accelerator operation groove, and moves the working machine up and down in the vertical figup operation groove 85. be able to.

  As described above, the embodiment has the advantage that the number of operation levers can be reduced and the periphery of the steering wheel can be cleaned, and the occurrence of erroneous operations can be extremely reduced, and the operation is easier than before. There are features.

  Next, an embodiment of an auxiliary brake device in a tow tractor will be described with reference to FIG. The auxiliary brake device according to the embodiment is provided in a trailer pulled by the tractor 86, and is configured to be used by detachably connecting a hydraulic hose to the external hydraulic pressure take-out device 87 on the tractor 86 side. As shown in the drawing, the hydraulic device 88 is configured such that hydraulic oil can be supplied to and discharged from the auxiliary brake device by operating a hydraulic operation lever 89 connected to the side portion. And as can be seen from the drawings, the tractor 86 is equipped with left and right brake devices 90, 90, and brake lots 91, 91, brake arms 92, 92, and brake pedals 93, 93 are connected to each other. Alternatively, the brakes can be operated by connecting and stepping on the left and right simultaneously.

  As described above, the auxiliary brake device according to the embodiment can be used simultaneously with the brake devices 90, 90 on the tractor side to ensure safety during parking. The embodiment is characterized in that the auxiliary brake device provided in the trailer can be braked using the external hydraulic pressure take-out device 87 of the tractor 86.

  And if the auxiliary brake device equipped in the trailer is structured such that the operation lever 89 of the hydraulic device 88 is mechanically connected to and interlocked with the brake arm 92 or the brake lot 91 of the tractor 86, the brake pedal of the tractor 86 The hydraulic device 88 can be interlocked and operated through the external hydraulic pressure take-out device 87 only by depressing operations 93, 93.

  Furthermore, if the hydraulic device 88 is configured to be interlocked by electrical means with a series of operation systems below the brake pedals 93, 93 of the tractor 86, manual operation of the hydraulic operation lever 89 is omitted. be able to.

  In this way, the auxiliary brake device provided in the trailer can be braked by hydraulic pressure using the external hydraulic pressure take-out device 87 provided in the tractor 86.

Schematic showing the control mechanism of the tread adjuster The figure which shows an example of a display of the measurement value of the stroke sensor displayed on a display panel, and the figure which shows an example of the display which the measurement value of this sensor changes with a tread change operation Horizontal cross section of rear axle case showing tread adjuster Tractor side view Tractor back view Top view of the front fender attached Front view of previous Fig. 6 Slope view of front fender mounting device Slope view of front fender mounting device Frontal fender mounting device Front axle front view Slope view showing front axle breather Slope view showing front axle breather Breezer slope map Side view of brake switch sensor box Side view of the action of the brake pedal arm and sensor Plan view of a conventional control lever box Plan view of the operation lever box of this embodiment Slope view of the operating lever box of the proposed embodiment The side view of the brake operation apparatus of an tractor and an external hydraulic pressure taking-out apparatus.

Explanation of symbols

1 Vehicle 2, 2 Wheel 3, 3 Hydraulic cylinder 4, 4 Hydraulic valve 5, 5 Stroke sensor T Normal stroke time α Correction time added to set the total stroke time.

Claims (2)

  A hydraulic cylinder (3, 3) is provided for changing and adjusting the tread of the left and right wheels (2, 2) pivoted on the vehicle (1), and the hydraulic cylinder (3, 3) is hydraulic oil based on a control signal. The hydraulic cylinders (4, 4) are connected to each other, and the hydraulic cylinders (3, 3) are provided with stroke sensors (5, 5), respectively, so that changes in the tread can be measured. After supplying hydraulic oil to the hydraulic cylinders (3, 3) by (4, 4) and performing a predetermined tread change output, the measured value of the stroke sensor (5, 5) corresponding to the tread change output Is not obtained, the controller (22) is configured to stop the tread change output after a time (T + α) obtained by adding a predetermined correction time (α) to the normal stroke time (T) by the tread change output. Tread adjustment control device for a working vehicle.   The tread adjustment control device for a work vehicle according to claim 1, wherein when the weight of the vehicle (1) increases, the correction time (α) is set longer.

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