JP2009179212A - Working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering control mechanism for making turning radii the same, even if a difference between tread widths of wheels journaled on a vehicle exists, when a steering operation of a steering wheel is operated at the same turning angle in the turning control of a tractor etc. <P>SOLUTION: In this steering control mechanism, right and left rear wheels 5 journaled on the working vehicle 4 are constituted to change and adjust the tread widths by an elongating and contracting operation of a hydraulic cylinder, turning angle data of the right and left front wheels 2 related to the turning control are determined corresponding to the tread widths of the rear wheels, and the turning angle data corresponding to the selected tread width are automatically set when changing and adjusting the tread widths in a controller. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

  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, the applicant of the present application. There are known techniques filed by.

  A tread change 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, Or, when it is detected that the tread of the rear wheel is in the changed state, the left and right rear wheels until the on / off switch that changes the tread can be changed from "On" to "Off" or 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

  Conventionally, this type of work vehicle, especially agricultural tractors, is mostly equipped with a tread width change / adjustment mechanism to adjust the left and right wheel positions to the ridge width of the field. Among them, there is a vehicle equipped with a turning control mechanism based on the control of a controller. Usually, the turning control mechanism of a work vehicle is related to the steering operation of the front wheel by the steering operation of the steering handle, for example, by disengaging the side clutch inside the turning or by operating the side brake inside the turning. While applying braking to the wheels, the turning range (turning radius) is narrowed (turning radius is reduced) so that the turning is effective.

  In such turning control, even if the steering operation of the steering handle is operated at the same turning angle, a large difference in turning radius occurs due to the difference in the tread width of the wheel that is pivoted on the vehicle. was there.

  Also, the turning radius of the work vehicle in turning control is greatly affected by the size of the tire, as well as the difference in the tread width.For example, instead of a small diameter tire, a large diameter tire is installed, When turning control is performed based on the same turning angle data, there is a problem that the turning radius greatly differs.

In order to solve the above problems, the present invention takes the following technical means.
First, the invention described in claim 1 is a work vehicle (4) in which turning control is performed by the controller (3) when the left and right front wheels (2) and (2) are steered by operating the steering handle (1). The left and right rear wheels (5), (5) pivoted on the work vehicle (4) are configured such that the tread width can be changed and adjusted by the expansion and contraction operation of the hydraulic cylinders (6), (6). The turning angle data of the left and right front wheels (2), (2) related to the turning control is determined according to the tread width of the rear wheels (5), (5), and the controller (3) When the tread width is changed and adjusted, the cutting angle data corresponding to the selected tread width is automatically set.

  Since the cutting angle data determined according to the tread width is automatically set every time the tread is changed, the turning control action performed after adjusting the tread width also turns with the turning radius that is almost the same as before the adjustment. It became something that could be done. In addition, since the cutting angle data is automatically updated according to the tread width, there is also an advantage that it is possible to omit the operation of changing the setting.

  According to a second aspect of the invention, the turning angle data related to the turning control is determined for each size of the tire (7) to be mounted on the work vehicle (4), and the controller (3) When the tire (7) of the vehicle (4) is changed to another tire (7) having a different size and the size setting operation is performed, the cutting angle data corresponding to the size is automatically set. The construction of the work vehicle according to claim 1.

  When a tire size setting operation is performed after changing to a tire having a different size, the cut angle data corresponding to the size is automatically updated.

  First, since the invention according to claim 1 is configured to automatically set predetermined cut angle data every time the tread is changed according to the tread width, the turning control operation performed after the tread adjustment is also performed before the adjustment. There is an excellent feature that it is possible to turn at a turning radius that is almost the same as that of the turning.

In addition, since the cutting angle data is automatically updated according to the tread width, there is also a feature that it is possible to save time and effort for operations such as setting change.
The invention of claim 2 is characterized in that, when a setting operation is performed by changing to a tire having a different size, the cutting angle data corresponding to the size is automatically updated. Conventionally, a large or small difference has occurred in the turning radius during turning control every time the tire is replaced, but this problem can be solved by the present invention.

  Hereinafter, the present invention will be described in detail with reference to an example of a tread adjusting device and a turning control mechanism equipped in the agricultural tractor 4 (corresponding to the work vehicle 4 of the present application) shown in the drawings.

  First, as shown in FIGS. 4 and 5, the tractor 4 has an engine 11 mounted in a front bonnet 10, and a clutch housing and a gear-type transmission that houses a main clutch at the rear of the engine 11. The mission case 12 to be connected is integrally connected. A tread-adjustable rear axle case 13 is provided on both the left and right sides of the mission case 12, and rear wheels 5 and 5 are provided on the ends of the case 13 on both the left and right sides.

A front axle case is provided below the engine 11 so as to be able to roll around the front and rear axis, and front wheels 2 and 2 are provided to be steerable on both side ends.
The cockpit 14 is provided in a cabin 15 mounted on the vehicle body, and the meter panel 16, the steering handle 1, and other operation levers are concentrated on the front side. Further, various setting devices such as a tread adjustment set switch 17 and a tread width setting dial 18 which will be described later (see FIG. 1) are provided in the vicinity of the levers, and these setting signals are a control unit below the cockpit 14. It is configured to input to the controller 3.

  In FIG. 4, a cylinder case 20 having a hydraulic cylinder for raising and lowering the work implement is provided at the rear upper part of the mission case 12. The lift arm 21 is configured to move up and down by extending and contracting the piston of the hydraulic cylinder in the cylinder case 20 and to move up and down the rear rotary tiller 22 connected thereto. One of the lift arms 21 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 21 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 turning control mechanism will be described.
As shown in FIG. 1, the controller 3 is configured such that when a steering angle sensor 25 is connected to the input side and the steering operation of the steering handle 1 is performed, the steering angle is detected and input. As shown in the drawing, the controller 3 is provided with a left solenoid valve 26 and a right solenoid valve 27 connected to the output side, and an oil path is electromagnetically switched by a control signal, so that a brake device (see FIG. 6) is provided. In this configuration, operations 28 and 29 are performed.

  When the detection information input from the steering angle sensor 25 is a left turn, the turning control by the controller 3 outputs a control signal to the left solenoid 26 inside the turn to switch the oil path, and the left brake device 28 is applied to brake the left rear wheel 5. On the contrary, if the vehicle turns right, the right brake device 29 is operated via the right solenoid valve 27 to apply a braking force to the right rear wheel 5. At that time, the controller 3 is configured to apply a braking force to the brake device 28 or 29 on the inner side of the turn as described above at a braking timing based on preset turning angle data.

  The turning angle data described above is determined in accordance with the tread width of the rear wheels 5 and 5, and the controller 3 uses the tread width setting dial 18 to change or adjust the tread width according to the configuration described later. When the tread width to be changed is set and then the tread adjustment set switch 17 is turned on, the cutting angle data corresponding to the tread width to be adjusted is automatically set and registered.

  Further, it is known that the turning radius during turning control varies depending on the tire size attached to the tractor 4. Therefore, the cutting angle data is determined for each size of the tire 7 attached to the tractor 4. Accordingly, when the controller 3 changes the tire 7 of the tractor 4 to another tire 7, the controller 3 operates the tire size setting device 23 of the meter panel 16, but in accordance with the operation, the controller 3 cuts off corresponding to the changed tire size. The corner data is set automatically.

Next, the tread adjusting device will be described.
First, in FIG. 6, the drive shafts 31, 31 extended left and right from the rear wheel differential mechanism 30 disposed at the center are left and right transmission cylinders 33 via the brake devices 28, 29 and speed reducers 32, 32, respectively. , 33 is configured to transmit traveling power. On the other hand, as shown in the drawing, the rear wheels 5 and 5 are pivotally attached to wheel shafts 34 and 34, respectively, and the wheel shafts 34 and 34 are supported by wheel support cases 35 and 35. It has become.

  As shown in FIG. 6, the wheel shafts 34 and 34 have front and rear rear wheels 5 and 5 that are telescopically extendable with respect to the transmission cylinders 33 and 33 on the vehicle body side (adjustment of the tread width). ) So as to be free to slide so that traveling power can be transmitted from the rear wheel differential mechanism 30 to the rear wheels 5 and 5.

  The hydraulic cylinders 6 and 6 for adjusting the tread fix the cylinder lot 36 to the housing case 37 (vehicle body side), and are provided between the transmission cylinders 33 and 33 and the outer wheel support cases 35 and 35. It consists of a cylinder chamber (outer) 6a and a cylinder chamber (inner) 6b, and the tread width can be adjusted by an expansion / contraction operation between the chambers 6a and 6b.

For the sake of explanation, the embodiment shown in FIG. 6 is illustrated in a state (position) when the left hydraulic cylinder 6 is contracted, and in a state (position) when the right cylinder 6 is expanded for easy understanding. Yes.
In this case, as shown in FIG. 6, the left and right hydraulic valves 40, 40 are respectively connected to an oil tank T (pump P) and both chambers 6a, 6b on the hydraulic cylinders 6, 6 side by pipes 41, 41, respectively. The cylinder chamber (outer) 6a is connected and drained from the left pipe 41, and the cylinder inner chamber 6b is supplied and drained from the right pipe 41 to expand and contract.

  The tread adjusting device configured as described above is performed by setting a tread width to be adjusted in advance with the tread width setting dial 18 shown in FIG. 1 and then turning on the tread adjustment set switch 17.

  As shown in FIG. 6, the stroke sensor 42 is provided along the side of the hydraulic cylinders 6 and 6 in parallel. First, the inner end is attached to the housing case 37 on the vehicle body side, and the outer end is Is fixed to the wheel support case 35 so that the tread width and its change can be measured.

  Next, as shown in FIG. 1, the controller 3 has a tread width adjustment set switch 17, a tread width setting dial 18, stroke sensors (left) (right) 42, 42, steering, The angle sensor 25 is connected to input each information.

  Then, the controller 3 has left and right hydraulic valves 40 and 40 that switch the oil passages of the hydraulic cylinders 6 and 6 that adjust the tread width to the output side, and a solenoid valve (left) that switches the oil passages to the brake devices 28 and 29 ( Right) 26 and 27 are connected.

  Then, the controller 3 receives the tire size to be replaced by communication from the tire size setting device 23 equipped to set the change of the tire size when the tire is replaced in the meter panel 16, and corresponds to the tire size. The cut angle data is set.

  In the tractor 4 configured as described above, when changing or adjusting the tread width, first, the tread width setting dial 18 is operated to set the tread width (adjusted tread width), and the tread width adjustment set switch 17 is turned on. When operated, the controller 3 outputs a control signal to the hydraulic valves (left) (right) to automatically perform the switching operation, and the expansion (or contraction) of the hydraulic cylinders 6, 6 causes the rear wheels 5, 5 to move. The tread width is changed / adjusted to the width set by the tread width setting dial 18.

  When the tread width of the rear wheels 5 and 5 is adjusted in this way, the controller 3 automatically selects one of the cut angle data A to E corresponding to the adjusted tread width as shown in the flowchart of FIG. Is set automatically.

  Then, the tractor 4 starts work by the operation of the operator. For example, when the tractor 4 reaches the end of the field and turns, the steering handle 1 is first turned in the turning direction. Then, when the controller 3 determines that the detected information (steering angle) input from the steering angle sensor 25 is a steering angle that exceeds a slight direction change degree, the controller 3 shifts to turning control. Then, the controller 3 uses a solenoid valve 26 for braking the brake device 28 or 29 on the inside of the turn according to the operation timing calculated based on the turning angle data set corresponding to the tread width, that is, the set turning angle, or The control signal is output to 27 and the oil path is switched and braked by the switching operation (FIG. 4).

  In this case, although the turning radius of the tractor 4 depends on the tread width of the rear wheels 5 and 5 even if the steering operation angle of the steering handle 1 is the same, the turning angle data corresponding to the tread width is set. Therefore, the braking force is applied to the rear wheel 5 on the inside of the turn at an appropriate timing, so that the turn radius is accurately controlled.

  As described above, according to the embodiment of the present invention, the predetermined turning angle data is automatically set in the controller 3 every time the tread width is changed according to the tread width. However, it is possible to turn at a turning radius that is almost the same as the turning control before adjustment.

  Moreover, the cutting angle data is automatically updated by the controller 3 in accordance with the tread width set by the tread width setting dial 18 as a tread width changing operation. There is an advantage that the trouble to do is omitted.

  Next, when the tire 7 having a different size shown in the flowchart of FIG. 3 is replaced, the tire size selected by communication from the tire size setting device 23 is input to the controller 3, and the cutting angle data corresponding to this size is automatically obtained. Is set automatically.

  As described above, in the embodiment, when the tire size setting device 23 is used to set the size on the meter panel 16 by replacing the tires having different sizes, the cutting angle data corresponding to the size is automatically displayed. Since the controller 3 is inputted and updated by the communication means, it is possible to eliminate problems such as a difference in the turning radius at the time of turning control as in the prior art. There is.

  Although the tread width setting dial 18 already described is not specifically illustrated, the tread width is set by manually turning the dial. However, instead of this dial type, FIG. As shown, the tread width may be divided into stages (1 to 5 in the embodiment), and a selection switch type configured by arranging LEDs for each stage may be used. This configuration has the advantage that the tread width setting operation becomes easy and can be easily set.

Next, an embodiment relating to the bracket 46 and the lock plate 47 for locking the adjustment position in the tread adjusting device for the rear wheels 5 and 5 will be described.
First, the tread width adjusting device has already been described with reference to FIG. 7, but in the case of the embodiment, as shown in FIG. 9, the cylinder chamber (outer) 6a of the hydraulic cylinder 6 is replaced with the wheel of the rear wheel 5. It is connected to the support case 35 so that the tread width can be changed and adjusted in the left-right direction. The bracket 46 has one end attached to the wheel support case 35 as shown in FIG. 9, and two long holes in the longitudinal direction as shown in FIGS. 10 (conventional configuration) and FIG. 11 (example). 48 and 48 are provided so as to be slidable and lockable. The lock plate 47 is applied from the outside, the lock bolt 49 is inserted from the outside, and the housing case 50 is screwed and fixed.

  In the conventional configuration shown in FIG. 10, the bracket 46 and the lock plate 47 are overlapped with the lock plate 47 on the outside of the bracket 46, the insertion hole 51 of the lock plate 47 is overlapped with the long holes 48 and 48, and from the outside. A lock bolt 49 is inserted and fixed to the housing case 50 by screwing.

  On the other hand, in the embodiment, as shown in FIG. 11, the lock holes 53 are formed at regular intervals on the outer sides of the two upper and lower long holes 48 provided in the bracket 46. The lock plate 47 is configured such that the lock pins 54 and 54 are arranged at predetermined intervals on the upper and lower ends and protruded so as to be inserted into the lock hole 53.

  In the embodiment configured as described above, the lock pin 54 of the lock plate 47 is inserted into the lock hole 53 of the bracket 46 when the wheel support case 35 is locked to the housing case 50 on the vehicle body side after the tread width is changed or adjusted. Further, the lock bolt 49 is screwed and fixed to the housing case 50 from the outside of the lock plate 47 through the insertion hole 51 and the long holes 48 of the bracket 46.

  Thus, as shown in FIG. 11, in the embodiment, the lock pin 54 of the lock plate 47 is inserted into and engaged with the lock hole 53 of the bracket 46 as compared with the conventional device (see FIG. 10). Since the bolt 49 (see FIG. 9) is screwed and fixed, the adjustment position, that is, the tread width can be reliably held. The embodiment is extremely effective in terms of manufacturing cost because it can be manufactured with a slight increase compared to the conventional product.

  Next, as shown in FIG. 12, when the tractor 4 travels on an inclined land along a slope (along a contour line) by a plowing operation, the weight of the wheel 5 traveling on the upper side of the slope becomes light. Thus, the tread width can be easily corrected for the upper wheel 5. Therefore, when the tractor 4 changes or adjusts the tread width and one side does not move correctly to the width initially set by the tread width setting dial 18, for example, when the plow operation is performed on an inclined ground, Therefore, the upper wheel 5 can be easily changed / adjusted.

  Further, when the tread width is widened during such a plowing operation, the tread width of the rear wheel 5 that has fallen into the groove tends to be narrow (return to the original). This is because the load of the vehicle body acts on the rear wheel 5 on the side falling in the groove. Therefore, when the tread width of the rear wheel 5 that has fallen into the groove is narrow (returns to the original) as described above, the tread width of the wheel 5 that has not fallen into the opposite groove is increased. To do. Thereby, the set tread width between the left and right rear wheels 5, 5 can be secured.

  In this case, when changing the tread width, the tractor 4 can easily change and adjust both the left and right wheels 5 and 5 by reciprocating the slope and changing the tread width by one wheel 5 located on the upper side. There are advantages.

Next, the embodiment shown in FIGS. 13 and 14 will be described.
In this embodiment, the lock bolt 49 described in the embodiment shown in FIGS. 9 and 10 is replaced with a telescopic cylinder.

  That is, as shown in the drawing, the cylinder-type lock bolt 60 is provided in the lock hole 61 of the bracket 46 and is inserted into the fixing hole 63 of the housing case 62 so as to be locked at the adjustment position.

  Conventionally, the adjustment of the front wheel tread width performed by the farmer has been unfamiliar, and many lock bolts have been tightened poorly. In this example, the lock bolt is a cylinder type for changing and adjusting the tread width of the front wheel. Therefore, it automatically extends and operates and engages with the fixing hole 63 so that the position can be reliably fixed.

Next, an embodiment of the unconnected alarm lamp 66 in the left and right brake pedals 65 and 65 of the tractor 4 will be described with reference to FIGS. 15 and 16.
Conventionally, this type of warning lamp is configured such that when the left and right pedals are not connected, it is electrically detected that the left and right pedals are not connected, and a warning lamp is used to warn the cockpit meter panel. Yes.

  On the other hand, in the embodiment, as shown in FIGS. 15 and 16, the unconnected alarm lamp 66 is provided on the upper surface of the connection plate 67 so that the alarm lamp 66 is not visible to the operator when in the connected state. . Therefore, the alarm lamp 66 can be seen by the operator only when the alarm lamp 66 is in the non-connected state as shown in FIG. 15, and the left and right brake pedals 65, 65 are connected to the connecting plate 67 as shown in FIG. When connected, it is on the back side of the pedal and cannot be seen.

  As described above, since the unconnected alarm lamp 66 of the embodiment is attached to the connecting plate 67, when both the pedals 65 and 65 are connected, they are hidden behind and cannot be seen. As shown in FIG. In addition, it is in a position where the operator can visually check. The unconnected alarm lamp 66 is configured to always be in an ON state and ensure safety while the engine is being driven.

  In this way, the embodiment eliminates the need for wiring such as a harness and simplifies the configuration as compared with a configuration that warns with a warning lamp provided on a meter panel in a conventional cockpit. There is a feature that could be achieved.

Controller block diagram showing the control mechanism Flow chart of action Flow chart of action Flow chart of action Tractor side view Rear view of the tractor showing a partial section Cross section of tread width adjustment mechanism Tread width setting device according to embodiments Sectional drawing of a part of the tread adjusting mechanism of another embodiment Conventional bracket and lock plate side view Side view of the bracket and lock plate of the embodiment Rear view of the tractor of the embodiment Slope view of the bracket of the embodiment The partially broken top view which shows the locked state of an Example Slope view with left and right brake pedals disconnected The slope figure which made the brake pedal on either side connect.

Explanation of symbols

1 Steering handle 2, 2 Left and right front wheels 3 Controller 4 Work vehicle 5, 5 Left and right rear wheels 6, 6 Hydraulic cylinder 6a Cylinder chamber (outside)
6b Cylinder chamber (inside)
7 tires

Claims (2)

  When the left and right front wheels (2), (2) are steered by operating the steering handle (1), in the work vehicle (4) in which turning control is performed by the controller (3), the work vehicle (4) is pivoted. The left and right rear wheels (5) and (5) are configured such that the tread width can be changed and adjusted by the expansion and contraction operation of the hydraulic cylinders (6) and (6), and the left and right front wheels (2 ), (2), the cutting angle data is determined in accordance with the tread width of the rear wheels (5), (5), and the controller (3) selects the tread width selected when adjusting the tread width. A work vehicle having a configuration in which cut angle data corresponding to is automatically set.   The turning angle data related to the turning control is determined for each size of the tire (7) to be mounted on the work vehicle (4), and the controller (3) sizes the tire (7) of the work vehicle (4). The work vehicle according to claim 1, wherein when the tire is changed to another tire (7) having a different size and the size setting operation is performed, the cutting angle data corresponding to the size is automatically set. .

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