JP2001130438A - Travel speed control system of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the risk that an operator will be thrown off a work deck when the moving direction of a vehicle body is changed. SOLUTION: This travel speed control system 40 comprises a left hydraulic travel motor 15 and a right hydraulic travel motor 16 for driving a pair of undercarriages arranged in the left and right of a vehicle body, a left operating lever 31L and a right operating lever 31R by which the operation of the hydraulic motors 15 and 16 is controlled, a left potentiometer 45 and a right potentiometer 46 for outputting a voltage value or operation signal depending upon the tilting travel of the operating levers 31L and 31R from their neutral position, and a controller 41 for controlling the operation of operation control valves 47 and 49 connected to the hydraulic motors 15 and 16 so that the rotational frequency of the hydraulic motor 15, 16 that is controlled by the operating lever 31L, 31R with the longer tilting travel is reduced below that corresponding to the tilting travel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling speed control device for a vehicle, and more particularly, to a left traveling hydraulic motor and a right traveling hydraulic pressure for rotationally driving a pair of crawler traveling bodies provided on both right and left sides of a vehicle body. The present invention relates to a traveling speed control device for a vehicle having a motor and operation means for operating the rotation speed and direction of the motor.

[0002]

2. Description of the Related Art An aerial work vehicle that performs an aerial work includes a pair of crawler traveling bodies provided in a vehicle body width direction for running the vehicle body, and a boom that is provided on the vehicle body and that can be extended, retracted, undulated, and turned. Some of them are provided with a worktable provided at the end of the boom and on which a worker can board, and an operating device provided on the worktable for controlling the traveling speed and the moving direction of the vehicle. Each crawler traveling body is provided with a traveling motor that is operated by hydraulic pressure to rotationally drive the crawler traveling body, hydraulic fluid discharged from an engine-driven hydraulic pump is supplied to an operation control valve, and the operation control valve is operated by operating an operation device. Are configured to control the supply and discharge of hydraulic oil to control the operation of the traveling motor.

As a result, the operating speed of the pair of traveling motors can be controlled by operating the operating device, so that the vehicle can travel while changing the traveling speed and moving direction of the vehicle body.

[0004]

However, in recent years, the working speed of aerial work vehicles has been increasing, and the traveling speed of the vehicles has been increased. However, vehicles such as a pivot turn and a spin turn can be used. If the vehicle is rotated at a high speed when traveling straight ahead when the vehicle is rotated, a large centrifugal force acts on the work table when the vehicle rotates, particularly when the work floor of the work table is away from the turning center. For this reason, there is a possibility that the worker boarding the work table may be shaken off the work table,
The problem arises.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and a vehicle speed control apparatus for a vehicle in which a worker who is on a worktable does not fall down from the worktable even when the vehicle body rotates. The purpose is to provide.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a traveling speed control device for a vehicle according to the present invention is a traveling speed control device for a vehicle having a free-running vehicle body. Rotatable left traveling means (for example, left lower traveling body 5 in the embodiment) provided on both left and right sides of the vehicle
And a right traveling means (for example, the right lower traveling body 7 in the embodiment), a left traveling motor (for example, the left traveling hydraulic motor 15 in the embodiment) for driving the left traveling means, and a right traveling motor (for driving the right traveling means in the embodiment). For example, in order to operate the right traveling hydraulic motor 16) in the embodiment, the traveling speed and the rotation direction of the vehicle body, a tilt operation can be performed around the neutral position, and the tilt operation can be performed based on the tilt operation amount and the operation direction from the neutral position. Left operating means (for example, left operating lever 31L in the embodiment) and right operating means (for example, right operating lever 31R in the embodiment) for setting the rotation speed and the rotating direction of the left running motor and the right running motor; If the right and left operating means are operated in the same direction from the neutral position, or if one of the left operating means and the right operating means remains in the neutral position and the other is in the neutral position When operated, the rotation speed of the traveling motor operated by the operation means having the larger tilt operation amount is smaller than the rotation speed corresponding to the tilt operation amount, and corresponds to the operation means having the smaller tilt operation amount. Traveling motor operation control means for operating at a rotation speed greater than the rotation speed and operating the rotation speed of the traveling motor operated by the operation means at the smaller or tilting operation amount at a rotation speed corresponding to the tilting operation amount (For example, the controller 41 in the embodiment).

When the left operating means and the right operating means are operated in the same direction from the neutral position, or when one of the left operating means and the right operating means is operated in the neutral position while the other is operated from the neutral position, The traveling motor operation control means is adapted to set the rotation speed of the traveling motor operated by the operation means having the larger tilt operation amount to be smaller than the rotation speed corresponding to the tilt operation amount and to correspond to the operation means having the smaller tilt operation amount. The motor is operated at a rotation speed higher than the rotation speed, and the rotation speed of the traveling motor operated by the operation means located at the position where the tilt operation amount is smaller or at the neutral position is operated at a rotation speed corresponding to the tilt operation amount.

When the left operating means and the right operating means are operated in the same direction from the neutral position, and the operation amounts of the two operating means are different (hereinafter, referred to as "the operation of changing the moving direction of the vehicle body"). The rotation speed of the travel motor operated by the operation means having the larger tilt operation amount is set to be smaller than the rotation speed corresponding to the tilt operation amount, so that the difference between the rotation speeds of the left travel motor and the right travel motor is set. , The change in the moving direction of the vehicle body can be slowed, and it is possible to prevent the possibility that an operator who has boarded the work table is shaken off the work table.

When one of the left operating means and the right operating means is operated from the neutral position while one of the left operating means remains at the neutral position (hereinafter referred to as "the case where an operation of pivoting the vehicle body is performed"). Since the rotation speed of the traveling motor operated by the operated operation means is set to be smaller than the rotation speed corresponding to the tilt operation amount of the operation means, the rotation speed of the operated traveling motor is reduced and the rotation of the pivot turn is reduced. The speed can be reduced, and it is possible to prevent the possibility that the worker who has boarded the worktable is shaken off the worktable. The left traveling motor and the right traveling motor may be exemplified by a hydraulic motor that operates by supplying hydraulic oil and an electric motor that operates by supplying electric power.

In the above vehicle speed control device,
The traveling motor operation control means is configured such that when the left operating means and the right operating means are operated in the same direction from the neutral position, or when one of the left operating means and the right operating means remains in the neutral position and the other is operated from the neutral position In the case, the rotation speed of the traveling motor operated by the operation means having the larger tilt operation amount is changed to the rotation number corresponding to the operation means having the larger tilt operation amount and the rotation number corresponding to the operation means having the smaller tilt operation amount. The value obtained by multiplying the difference between the numbers by a coefficient smaller than 1.0 and the rotation speed corresponding to the operation means with the smaller tilt operation amount may be set to a value.

When the operation for changing the moving direction of the vehicle body is performed or the operation for pivotally turning the vehicle body is performed, the traveling motor operation control means is controlled by the operation means operated by the operation means having the larger tilt operation amount. The tilt operation is performed by multiplying the difference between the rotation speed of the motor that corresponds to the operation means with the larger tilt operation amount and the rotation speed corresponding to the operation means with the smaller tilt operation amount by a coefficient smaller than 1.0. By setting a value obtained by adding the number of rotations corresponding to the operation means having the smaller amount, the difference between the number of rotations of the traveling motor having the larger amount of tilting operation and the number of rotations of the traveling motor having the smaller amount of tilting operation can be obtained. Since the size is reduced, the change in the moving direction of the vehicle body and the rotation speed can be reduced, and it is possible to prevent the possibility that the worker who has boarded the work table is shaken off the work table.

Further, the vehicle traveling speed control device of the present invention is a vehicle traveling speed control device having a free-running vehicle body, and is provided on both right and left sides of the vehicle body for traveling the vehicle body. A traveling means and a right traveling means, a left traveling motor for driving the left traveling means and a right traveling motor for driving the right traveling means, and tilting back and forth around a neutral position to operate a traveling speed and a rotation direction of the vehicle body. Left operating means and right operating means which are operable and set the rotational speed and rotating direction of the left running motor and the right running motor in accordance with the tilt operation amount and the operating direction from the neutral position, and the left operating means and the right operating means Is operated from the neutral position in the forward and backward directions, the rotation speed of the traveling motor operated by each operation means is larger than 0 and smaller than the rotation number corresponding to the tilt operation amount of each operation means. And a driving motor actuation control means for actuating at a rotational speed constituting.

When the left operating means and the right operating means are operated in the forward and backward directions from the neutral position (hereinafter, referred to as "the case where the operation of spinning the vehicle body is performed").
The traveling motor operation control means operates the rotation speed of the traveling motor operated by each operation means at a rotation number larger than 0 and smaller than the rotation number corresponding to the tilt operation amount of each operation means. For this reason, even if the vehicle body makes a spin turn, the rotation speed can be reduced, and the possibility that the worker who has boarded the work table is shaken off the work table can be prevented beforehand.

In the above configuration, when the left operating means and the right operating means are operated in the forward and backward directions from the neutral position, the running motor operation control means controls the rotation speed of the running motor operated by each operating means. A value obtained by multiplying the number of rotations corresponding to each operation means by a coefficient smaller than 1.0 may be set.

When an operation of spinning the vehicle body is performed, the rotation speed of the traveling motor operated by each operation means is set to a value obtained by multiplying the rotation speed corresponding to each operation means by a coefficient smaller than 1.0. Then, the traveling motor operation control means controls the rotation speed of the traveling motor so that the newly set rotation speed is obtained. For this reason, the rotation speed of the vehicle body that performs the spin turn can be reduced, and the possibility that the worker who has boarded the work table swings off the work table can be prevented.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. This embodiment shows an embodiment of a self-propelled aerial work vehicle having a pair of crawler-type lower traveling bodies at both ends in the width direction of a vehicle body. Before describing the vehicle traveling speed control device of the present invention at first, an aerial work vehicle equipped with the traveling speed control device will be described. As shown in FIG. 1, the aerial work vehicle 1 has a crawler-type lower left traveling body 5 and a right lower traveling body 7 at both ends in the width direction of the vehicle body 3. Left lower traveling body 5 and right lower traveling body 7
Are provided on the inside of the crawler belt 9, a starting wheel 11 provided inside the vehicle body front side of the crawler belt 9 for driving the crawler belt 9, and provided on the inside of the crawler belt 9 behind the vehicle body for guiding the crawler belt 9. It comprises an idler wheel 13, a left traveling hydraulic motor 15 and a right hydraulic traveling hydraulic motor 16 provided inside the starting wheel 11 for rotating the starting wheel 11.

A turntable 17 that can turn freely is provided on the upper part of the vehicle body 3.
Is provided in the vehicle body 3 below the turntable 17, and a turn motor (not shown) is provided, and the turntable 17 is turned by the operation of the turn motor. Swivel 1
7 has a concave groove 19 formed in the front-rear direction of the vehicle body 3.
The concave groove 19 is configured so that the telescopic boom 21 can be stored. The telescopic boom 21 is formed in a telescoping manner and can be freely extended and retracted, and the base of the telescopic boom 21 is pivotally connected to the inside of a pair of pivoting plates 23 erected above the concave groove 19 at the rear of the vehicle body. An up / down cylinder 25 is pivotally connected between the lower part of the side wall of the telescopic boom 21 and the bottom of the concave groove 19, and the telescopic boom 21 is configured to move up and down when the up / down cylinder 25 is moved.

At the distal end of the telescopic boom 21, there is provided a bottomed cylindrical work table 27 on which a worker (not shown) can ride. A leveling device (not shown) is connected to the workbench 27, and when the telescopic boom 21 is raised and lowered, the leveling device is operated and the workbench 27 is always kept in a horizontal state. The workbench 27 is provided with a boom operating device 29 that moves the telescopic boom 21 up and down, expands, contracts, and turns, and a traveling operation device 31 that operates the traveling speed and rotation direction of the vehicle.
The traveling operation device 31 includes a left operating lever 31L and a right operating lever 31 for operating the left traveling hydraulic motor 15 of the left lower traveling body 5 and the right traveling hydraulic motor 16 of the right lower traveling body 7.
R.

Next, a description will be given of a vehicle traveling speed control device. The traveling speed control device is a device for controlling the traveling direction and traveling speed of the vehicle. When the traveling direction of the vehicle body 3 is changed (particularly, when the vehicle body 3 is pivot-turned or spin-turned), the traveling speed of the vehicle body 3 is increased. It is a device that makes it slower than that of. The traveling speed control device 40 includes a traveling operation device 31, a controller 41, and a hydraulic circuit 4 as shown in FIG.
3 are provided.

The traveling operation device 31 has a left operation lever 31L and a right operation lever 31R arranged at an upper portion thereof with a predetermined gap therebetween. In addition, the left operation lever 31L
And the right operation lever 31R are collectively referred to simply as “operation levers 31L and 31R”. The operation levers 31L and 31R can be tilted in the front-rear direction (front-back (F-B) direction in FIG. 2) around a neutral position (vertically upper position), and the left operation lever 31L and the right operation lever 31R are moved forward ( F direction)
The left traveling hydraulic motor 15L and the right traveling hydraulic motor 15R rotate forward to move the vehicle body 3 shown in FIG. 1 forward (upward as shown in FIG. 1), and the left operating lever 31L and the right operating lever 31R. Is tilted backward (direction B), the left traveling hydraulic motor 15L and the right traveling hydraulic motor 15R
Rotates in the reverse direction, and the vehicle body 3 shown in FIG. 1 moves rearward (downward as shown in FIG. 1).

The traveling operation device 31 has a left potentiometer 45 and a right potentiometer 46 built therein. When the left operation lever 31L is tilted in the front-rear direction, the left potentiometer 45 is operated to generate a left operation signal that is a voltage value corresponding to the inclination angle from the neutral position of the left operation lever 31L. . Also, the right operation lever 31
When R is tilted back and forth, the right potentiometer 4
6 is operated to generate a right operation signal which is a voltage value corresponding to the inclination angle from the neutral position of the right operation lever 31R.

The controller 41 includes the left potentiometer 4
5 and a function of controlling the traveling speed and the rotation direction of the vehicle body 3 based on the left operation signal and the right operation signal output from the right potentiometer 46. That is, when the left operation lever 31L and the right operation lever 31R are operated in the same direction from the neutral position, or when the left operation lever 31L and the right operation lever 3
When one of the 1Rs is kept at the neutral position and the other is tilted from the neutral position, the controller 41 moves the vehicle body 3 straight, changes the moving direction of the vehicle body, or pivots the vehicle body. When the left operating lever 31L and the right operating lever 31R are operated in the forward and backward directions from the neutral position, the controller 41 causes the vehicle body 3 to spin turn. Here, when the controller 41 changes the moving direction of the vehicle body 3, pivots the vehicle body 3, or spins the vehicle body 3, the controller 41 controls the speed or rotation when the traveling direction of the vehicle body 3 is changing. Make the speed slower than when traveling straight.

The hydraulic circuit 43 is connected to the engine E
It is configured to include a continuous hydraulic pump P, a left traveling hydraulic motor 15, a right traveling hydraulic motor 16, a left operation control valve 47, and a right operation control valve 49. Hydraulic oil discharged from the hydraulic pump P is supplied to the left operation control valve 47 and the right operation control valve 49, and the left operation control valve 47 and the right operation control valve 49 perform supply / discharge control of the operation oil, and the left traveling hydraulic motor 15 and the operation of the right traveling hydraulic motor 16 are controlled. The operation control of the left operation control valve 47 and the right operation control valve 49 is performed by the controller 41.

Next, the operation of the traveling speed control device 40 of the present invention is explained by moving the vehicle body 3 straight, changing the direction of the vehicle body 3,
A case where the vehicle body 3 is pivot-turned and a case where the vehicle body 3 is spin-turned will be described. First, body 3
A case where the vehicle body is moved straight ahead, the direction of the vehicle body 3 is changed, and the vehicle body 3 is pivotally turned will be described. Here, before describing the operation, the contents shown in FIG. 3 will be described. It should be noted that the contents shown in FIG. 4 are the same as those shown in FIG. FIG. 3 is a plan view showing a state in which the operation positions of the left operation lever 31L and the right operation lever 31R of the traveling operation device 31 are changed. For example, as shown in the first column of FIG. In the rectangular frame 51, a horizontal line segment 51H and a vertical line segment 51V are drawn, and both ends of the horizontal line segment 51H and the left and right pieces 53 of the rectangular frame 51 are connected by a left operating lever. The neutral position of 31L and the right operating lever 31R are shown.
The vertical line segment 51V indicates the tilt direction of the operation levers 31L and 31R, and the positions of both ends of the upper and lower pieces 55 of the rectangular frame 51 are the maximum allowable operation points (+ MAX, -MAX) of the left operation lever 31L and the right operation lever 31R. Is shown.

In FIG. 3, the symbol "."
1L and the operation position when the right operation lever 31R is operated, and the “O” mark indicates that the controller 41 shown in FIG. 2 controls the rotation speed of the traveling hydraulic motors 15 and 16 according to the operation positions of the operation levers 31L and 31R. In this case, the operation positions of the operation levers 31L and 31R corresponding to the controlled number of rotations are shown. In other words, “•” marks indicate the operation positions of the operation levers 31L and 31R corresponding to the input values of the operation signals input to the controller 41 from the left potentiometer 45 and the right potentiometer 46 shown in FIG.
The “O” marks indicate the operating positions of the operating levers 31L, 31R corresponding to the output values of the control signals for controlling the rotation speeds of the traveling hydraulic motors 15, 16 based on the output values of the left potentiometer 45 and the right potentiometer 46. Show.

The contents of each figure will be described below. FIG. 3 (a)
As shown in the first row of FIG. 3, the left operating lever 31L and the right operating lever 31R move forward (upward in FIG. 3) from the neutral position.
Is operated to the maximum allowable operation point of the left potentiometer 4 electrically connected to the left operation lever 31L shown in FIG.
5 and a right potentiometer 46 electrically connected to the right operation lever 31R output a left operation signal (voltage signal) and a right operation signal (voltage signal) according to the amount of tilt operation of the operation levers 31L and 31R. 41 receives these operation signals.

When the controller 41 receives the operation signals, the controller 41 determines from the left operation signal and the right operation signal that the operation directions of the operation levers 31L and 31R are the same, and then reduces the magnitudes of the voltage values of these operation signals. Compare,
It is determined that the magnitudes of the voltage values are the same. Then, the controller 41 sends operation control signals corresponding to the respective operation signals to the operation control valves 47 and 49 so that the left traveling hydraulic motor 15 and the right traveling hydraulic motor 16 rotate in the forward direction at the same high speed. The operation of the operation control valves 47 and 49 is controlled.
Thus, the vehicle body 3 shown in FIG. 1 moves straight forward at high speed.

In the second column of FIG. 3B, the left operation lever 31L and the right operation lever 31R are tilted to a half of the tilt operation amount from the neutral position to the maximum allowable operation point forward. 3C shows a state in which the left operation lever 31L and the right operation lever 31R are in the neutral position, and the second column in FIG. FIG. 3E shows a state in which the operation lever 31L and the right operation lever 31R are tilted backward from the neutral position to a tilt operation amount that is half of the tilt operation amount that reaches the maximum allowable operation point, and the third column in FIG. Left operating lever 31L and right operating lever 31R
Is tilted downward from the neutral position to a tilt operation amount that reaches the maximum allowable operation point.

These operations are described in the first part of FIG.
The description of the operation is omitted because it follows the operation of the column,
In the second row of FIG. 3B, the vehicle body 3 shown in FIG. 1 moves straight forward at a medium speed, and in the third row shown in FIG.
Is stopped, and in the second row shown in FIG. 3 (d), the vehicle body 3 moves straight forward at a middle speed, and in the third row shown in FIG. 3 (e), the vehicle body 3 moves rearward at a high speed. Go straight.

Next, a case where the traveling direction of the vehicle body 3 is changed will be described. As shown in the second column of FIG. 3A, the left operation lever 31L is tilted forward from the neutral position to a tilt operation amount that is half of the tilt operation amount from the neutral position to the maximum allowable operation point, and the right operation lever 31R is moved. When the front operation is performed from the neutral position to the maximum allowable operation point, a left operation signal (voltage signal) and a right operation signal (voltage signal) corresponding to each tilt operation amount of the left operation lever 31L and the right operation lever 31R are shown in FIG. Is sent to the controller 41 shown in FIG.

After determining that the operating directions of the operating levers 31L and 31R are the same from the left operating signal and the right operating signal, the controller 41 compares the magnitudes of the voltage values of the left operating signal and the right operating signal. The rotation speed of the right traveling hydraulic motor 16 shown in FIG. 2 operated based on the operation signal of the right operation lever 31R having the larger tilt operation amount is changed to the operation signal of the right operation lever 31R having the larger tilt operation amount. An operation signal of the left operation lever 31L having a smaller tilt operation amount multiplied by a value obtained by multiplying a difference between the rotation speed corresponding to the traveling signal of the left operation lever 31L having the smaller rotation operation amount and the corresponding rotation speed by a coefficient 0.5. Is set to a value obtained by adding the number of rotations corresponding to. Here, the coefficient is not limited to 0.5 but may be any positive number smaller than 1.0. Then, the controller 41 determines this value (rotation speed).
An operation control signal for operating the right traveling hydraulic motor 16 is transmitted to the right operation control valve 49. Further, the controller 41 sends a left operation control signal to the left operation control valve 47 so that the rotation speed of the left traveling hydraulic motor 15 corresponding to the operation of the left operation lever 31L is set.

Then, the left operation control valve 47 and the right operation control valve 49 are operated and controlled in accordance with the respective operation control signals.
The left traveling hydraulic motor 15 rotates in the forward direction at a rotation speed corresponding to the operation signal of the left operation lever 31L, and the right traveling hydraulic motor 16 rotates at a lower rotation speed than the rotation speed corresponding to the operation signal of the right operation lever 31R. To rotate in the forward direction. For this reason, the vehicle body 3 shown in FIG. 1 moves while changing its direction to the front left at a low speed.

In the first row of FIG. 3B, the left operation lever 31L is operated from the neutral position to the maximum allowable operation point in the front, and the right operation lever 31R is moved from the neutral position to the maximum allowable operation point in the front. FIG. 3D shows a state in which the left operation lever 31L is operated backward from the neutral position to the maximum allowable operation point, and the right operation is performed in the third row of FIG. 3D. FIG. 3E shows a state in which the lever 31R is tilted backward from the neutral position to a tilt operation amount that is half of the tilt operation amount that reaches the maximum allowable operation point. Further, the second row in FIG. This shows a state in which the right operation lever 31R has been operated from the neutral position to the maximum allowable operation point rearward from the neutral position by operating to a position tilted to a half of the amount of tilt operation from the position to the maximum allowable operation point to the maximum allowable operation point. I have.

These operations are described in the second section of FIG.
The description of the operation is omitted because it follows the operation of the column,
In the first row of FIG. 3B, the vehicle body 3 moves to the front right while changing the direction at low speed, and in the third column of FIG. 3D, the body 3 moves to the rear right while changing the direction at low speed. And FIG.
In the second row of (e), the vehicle body 3 moves while changing its direction to the rear left side at a low speed.

Next, a case where the vehicle body 3 makes a pivot turn will be described. As shown in the third column of FIG. 3A, the left operation lever 31L is in the neutral position and the right operation lever 31L is in the neutral position.
When R is tilted forward from the neutral position to the maximum allowable operation point, the left operation signal (voltage signal) and the right operation signal (voltage signal) corresponding to each tilt operation amount of the left operation lever 31L and the right operation lever 31R are changed. It is sent to the controller 41 shown in FIG.

After determining that the right operating lever 31R has been operated from the neutral position while the left operating lever 31L remains at the neutral position, the controller 41 compares the magnitudes of the voltage values of the left operating signal and the right operating signal. Then, a value obtained by multiplying the rotation speed of the right travel hydraulic motor 16 corresponding to the operation signal of the right operation lever 31R having the larger tilt operation amount by a coefficient 0.5 is newly set as the rotation speed of the right travel hydraulic motor 16. . Here, the coefficient is not limited to 0.5 but may be any positive number smaller than 1.0. Then, the controller 41 sends an operation control signal corresponding to the set value to the right operation control valve 49. Also, since the left operation lever 31L is at the neutral position,
The controller 41 sends to the left operation control valve 47 an operation control signal for reducing the number of revolutions of the left traveling hydraulic motor 15 to zero.

The operation of the left operation control valve 47 and the right operation control valve 49 is controlled according to the respective operation control signals, the left traveling hydraulic motor 15 is stopped, and the right traveling hydraulic motor 16 is controlled by the right operating lever. The motor rotates in the forward direction at a low speed of half the speed corresponding to the operation signal of 31R. For this reason, the vehicle body 3 shown in FIG. 1 pivotally turns at the middle speed to the left front side with the left lower traveling body 5 as the turning center. For this reason, it is possible to prevent a worker who has boarded the worktable 27 shown in FIG.

In the third column of FIG. 3B, the left operation lever 31L is at the neutral position, and the right operation lever 31R is tilted by half the amount of tilt operation from the neutral position to the maximum allowable operation point forward. FIG. 3 shows a state in which the volume has been manipulated, and FIG.
In the first row of (c), the left operating lever 31L is operated forward from the neutral position to the maximum allowable operating point, and the right operating lever 31L is operated.
R indicates a state in which the lever is in the neutral position, and the second row in FIG. 3C shows that the left operating lever 31L is tilted forward to a maximum tilt operating amount of half of the tilt operating amount from the neutral position to the maximum allowable operating point. The right operation lever 31 </ b> R is in the neutral position. In the first row of FIG. 3D, the left operation lever 31L is at the neutral position, and the right operation lever 31R is tilted backward from the neutral position to a tilt operation amount that is half of the tilt operation amount from the neutral position to the maximum allowable operation point. The first row in FIG. 3E shows a state in which the left operation lever 31L is in the neutral position and the right operation lever 31R is operated backward from the neutral position to the maximum allowable operation point. .

These operations are the same as those described above with reference to FIG.
The description of the operation is omitted because it follows the operation of the column,
In the third row of FIG. 3B, the vehicle body 3 pivotally turns to the front left at a low speed, and in the first row of FIG. 3C, the vehicle body 3 pivots to the front right at a medium speed. In the second row of FIG. 3 (c), the vehicle body 3 pivotally turns to the front right at a lower speed, and in the first row of FIG. 3 (d), the vehicle body 3 pivots to the rear left at a lower speed. In the first row of (e), the vehicle body 3 makes a pivot turn to the rear left at a medium speed.

Next, a case where the vehicle body 3 makes a spin turn will be described. As shown in the first column of FIG. 4 (f), the left operation lever 31L is operated by a half of the tilt operation amount from the neutral position to the rear to the maximum allowable operation point, and the right operation lever 31R is neutralized. When the front operation is performed from the position to the maximum allowable operation point, the left operation lever 31L and the right operation lever 31R are operated.
The left operation signal (voltage signal) and the right operation signal (voltage signal) corresponding to each tilt operation amount are sent to the controller 41 shown in FIG.

The controller 41 determines that the operation levers 31L and 31R have been operated in opposite directions around the neutral position based on the left operation signal and the right operation signal, and then outputs the left operation signal and the right operation signal. A value obtained by multiplying each rotation speed of the left traveling hydraulic motor 15 and the right traveling hydraulic motor 16 based on the coefficient by a coefficient 0.5 is newly set as the rotation speed of the left traveling hydraulic motor 15 and the right traveling hydraulic motor 16.
Here, the coefficient is not limited to 0.5 but may be any positive number smaller than 1.0. Then, the controller 41 sends an operation control signal corresponding to the set value (rotation speed) to the left operation control valve 47 and the right operation control valve 49.

Then, the left operation control valve 47 and the right operation control valve 49 are operated and controlled according to the respective operation control signals.
The left traveling hydraulic motor 15 rotates in the reverse direction at a low speed, and the right traveling hydraulic motor 16 rotates in the forward direction at a medium speed. Then, the vehicle body 3 shown in FIG. 1 spins at a low speed in a counterclockwise direction around the center of the vehicle body 3 as a turning center. For this reason,
It is possible to prevent the possibility that the worker who has boarded the worktable 27 is shaken off the worktable 27 beforehand.

In the second column of FIG. 4F, the left operating lever 31L is operated backward from the neutral position to the maximum allowable operating point, and the right operating lever 31R is operated forward from the neutral position to the maximum allowable operating point. In the first row of FIG. 4 (g), the left operation lever 31L is operated to a tilt operation amount that is half of the tilt operation amount from the neutral position to the rearward maximum allowable operation point, and the right operation lever is operated. FIG. 4G shows a state in which the lever 31R has been operated to a tilt operation amount that is half of the tilt operation amount from the neutral position to the maximum allowable operation point in front. This shows a state in which the right operation lever 31 </ b> R has been operated from the neutral position to the maximum allowable operation point to the forward maximum allowable operation point by half of the tilt operation amount from the position to the maximum allowable operation point.

Further, in the first row of FIG. 4H, the left operating lever 31L is operated from the neutral position to the maximum allowable operating point in the front, and the right operating lever 31R is moved backward from the neutral position to the maximum allowable operating point. FIG. 4H shows a state where the left operation lever 31L is moved from the neutral position to the maximum allowable operation point in front of the left operation lever 31L. FIG. 4 shows a state in which the right operation lever 31R has been operated to a half of the tilt operation amount from the neutral position to the maximum allowable operation point rearward, and FIG. The first row of (i) shows a state in which the left operation lever 31L is operated from the neutral position to the maximum allowable operation point in the front, and the right operation lever 31R is operated rearward from the neutral position to the maximum allowable operation point. FIG.
The second row of (i) shows a state in which the left operation lever 31L has been operated forward from the neutral position to a tilt operation amount that is half the amount of tilt operation from the neutral position to the maximum allowable operation point, and the right operation lever 31R has been moved from the neutral position. This shows a state in which the operation has been performed backward to the maximum allowable operation point.

These operations are the same as those described with reference to FIG.
The description of the operation is omitted because it follows the operation of the column,
In the second row of FIG. 4F, the vehicle body 3 spins counterclockwise at a medium speed, and in the first row of FIG. 4G and the second row of FIG. 4 (h), the vehicle body 3 spins clockwise at a low speed in the first row, and in the second row of FIG.
Spin-turns at a lower speed in the clockwise direction, as shown in FIG.
In the first row, the vehicle body 3 spins clockwise at an intermediate speed, and in the second row of FIG. 4 (i), the vehicle body 3 spins clockwise at a low speed. Although the spin turn speed is expressed as a low speed in the first and second columns in FIG. 4H, the speed in the second column is lower than that in the first column. Speeds are different. In the above-described embodiment, the operation is performed as described above when the difference between the operation amounts of the left operation lever 31L and the right operation lever 31R is equal to or larger than a predetermined value.
Therefore, if the difference between the operation amounts does not exceed the predetermined value, the vehicle is in a straight running or stopped state.

[0046]

As described above, according to the vehicle traveling speed control apparatus of the present invention, the left operating means and the right operating means are operated in the same direction from the neutral position, and the operation amounts of the two operating means are different. In this case, the rotation speed of the traveling motor operated by the operation means having the larger tilt operation amount is set to be smaller than the rotation speed corresponding to the tilt operation amount, and the operation is performed by the operation means having the smaller tilt operation amount. By setting the rotation speed of the traveling motor to the rotation speed operated by the smaller operation means, it is possible to reduce the difference between the rotation speeds of the left traveling motor and the right traveling motor and to slow down the change in the moving direction of the vehicle body. In addition, it is possible to prevent the possibility that the operator who has boarded the work table is shaken off the work table beforehand. Further, when one of the left operating means and the right operating means is operated from the neutral position while the other is operated from the neutral position, the rotation speed of the traveling motor operated by the operated operating means is determined by the tilt operation amount of the operating means. By setting the rotation speed smaller than the rotation speed corresponding to, the rotation speed of the operating traveling motor can be reduced and the rotation speed of the pivot turn can be reduced, and the worker boarding the worktable is shaken off the worktable The fear can be prevented beforehand.

Further, when an operation of changing the moving direction of the vehicle body or an operation of pivot-turning the vehicle body is performed, the traveling motor operation control means is controlled by the traveling motor operated by the operation means having the larger tilt operation amount. Is calculated by multiplying the difference between the number of rotations corresponding to the operation means having the larger tilt operation amount and the number of rotations corresponding to the operation means having the smaller tilt operation amount by a coefficient smaller than 1.0 by a coefficient smaller than 1.0. When setting to a value obtained by adding the number of rotations corresponding to the operation means having a smaller amount of rotation, the difference between the number of rotations of the traveling motor having the larger amount of tilting operation and the number of rotations of the traveling motor having the smaller amount of tilting operation is calculated. It is possible to reduce the change in the moving direction and the rotation speed of the vehicle body by making the size smaller, and it is possible to prevent the possibility that the worker who has boarded the work table is shaken off the work table.

Further, when the left operating means and the right operating means are operated in the forward and backward directions from the neutral position, the running motor operation control means sets the rotation speed of the running motor operated by each operating means to be larger than 0. In addition, by operating at a rotation speed smaller than the rotation speed corresponding to the tilt operation amount of each operation means, even if the vehicle body spin-turns, the rotation speed can be reduced, and the worker who boarded the worktable can It is possible to prevent beforehand from being shaken off the worktable.

Further, the traveling motor operation control means controls the rotation speed of the traveling motor operated by each of the operating means when the left operating means and the right operating means are operated in the forward and backward directions from the neutral position. If the corresponding rotation speed is set to a value multiplied by a coefficient smaller than 1.0, the rotation speed can be reduced even if the vehicle spins,
It is possible to prevent the possibility that the worker who has boarded the work table is shaken off the work table beforehand.

[Brief description of the drawings]

FIG. 1 is a perspective view of an aerial work vehicle equipped with a traveling speed control device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a traveling speed control device according to one embodiment of the present invention.

FIG. 3 is a diagram for explaining an operation of the traveling speed control device according to the embodiment of the present invention.

FIG. 4 is a diagram for explaining an operation of the traveling speed control device according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 aerial work vehicle (vehicle) 3 vehicle body 5 left lower traveling body (left traveling means) 7 right lower traveling body (right traveling means) 15 left traveling hydraulic motor (left traveling motor) 16 right traveling hydraulic motor (right traveling motor) 31L left operating lever (left operating means) 31R right operating lever (right operating means) 40 traveling speed control device 41 controller (traveling motor operation control means)

Claims (4)

[Claims] 1. A traveling speed control device for a vehicle having a free-running vehicle body, comprising: a rotatable left traveling unit and a right traveling unit provided on both right and left sides of the vehicle body for traveling the vehicle body; A left traveling motor for driving a left traveling unit and a right traveling motor for driving the right traveling unit; and a tilting operation centering on a neutral position for operating a traveling speed and a rotation direction of the vehicle body; A left operating means and a right operating means for setting a rotational speed and a rotating direction of the left running motor and the right running motor in accordance with a tilt operation amount and an operating direction from the left and right operating means; When the operation is performed in the same direction from the position, or when one of the left operation unit and the right operation unit is operated from the neutral position while the other is operated from the neutral position, a large amount of tilt operation is performed. Operating the rotation speed of the traveling motor operated by the one operation means at a rotation speed smaller than the rotation speed corresponding to the tilt operation amount and larger than the rotation speed corresponding to the smaller operation means with the tilt operation amount, A vehicle having a traveling motor operation control means for operating the rotation speed of the traveling motor operated by the operation means having the smaller tilting operation amount or the neutral position at the rotation speed corresponding to the tilting operation amount. Traveling speed control device. 2. The traveling motor operation control means, wherein the left operating means and the right operating means are operated in the same direction from the neutral position, or one of the left operating means and the right operating means is in a neutral position. If the other is operated from the neutral position as it is, the rotation speed of the traveling motor operated by the operation means having the larger tilt operation amount is changed to the rotation speed corresponding to the operation means having the larger tilt operation amount. And a value obtained by multiplying a difference between the rotation speeds corresponding to the operation means having the smaller tilt operation amount by a coefficient smaller than 1.0 and a rotation speed corresponding to the operation means having the smaller tilt operation amount. 2. The vehicle running speed control device according to claim 1, wherein: 3. A traveling speed control device for a vehicle having a free-running vehicle body, comprising: a rotatable left traveling unit and a right traveling unit provided on both left and right sides of the vehicle body for traveling the vehicle body; A left traveling motor that drives a left traveling unit and a right traveling motor that drives the right traveling unit; and a tilting operation that can be tilted back and forth around a neutral position to operate a traveling speed and a rotation direction of the vehicle body. A left operating means and a right operating means for setting a rotational speed and a rotating direction of the left running motor and the right running motor in accordance with a tilt operation amount and an operating direction from a neutral position; and the left operating means and the right operating means When the front and rear directions are operated from the neutral position, the rotation speed of the traveling motor operated by each operation unit is set to a value greater than 0 and the rotation speed corresponding to the tilt operation amount of each operation unit. Speed control apparatus for a vehicle, comprising a driving motor actuation control means for actuating at low speed. 4. The travel motor operation control means, when the left operation means and the right operation means are operated in the front and rear opposite directions from the neutral position, respectively, determines the rotation speed of the travel motor operated by each operation means. 4. The vehicle traveling speed control device according to claim 3, wherein a value obtained by multiplying a rotation speed corresponding to each operation means by a coefficient smaller than 1.0 is set.