JPH0761794A - Control device for forklift - Google Patents

Abstract

PURPOSE:To set the rotating speed with high accuracy by providing an interlocking detecting switch for applying the power to lead switches of the respective modes of acceleration-holding-deceleration-stop in order by the power-on of an automatic switch in the case of providing a roll clamp for clamping a cylindrical product. CONSTITUTION:A rotating lever 10d, an automatic switch 20 and an interlocking detecting switch 21 are provided on the input side, and electromagnetic control valves 30, 31 for counter-clockwise and clockwise rotation and an unload electromagnetic switching valve are provided on the output side, centering round a controller 11. A roll clamp is rotated clockwise or counter-clockwise by the power-on of the automatic switch 30 to be rotated horizontally or vertically. When the interlocking detecting switch 21 is rotated with the above rotation, the increase/decrease of rotating speed is detected by a lead switch 211, the constant speed holding of the rotating speed is detected by a lead switch 212, the deceleration is detected by a lead switch 213, and the stop is detected by a lead switch 214, and the detection results of the respective lead switches are inputted to CPU 112 to control the electromagnetic control valves 30, 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forklift control device, and is particularly useful when applied to a forklift equipped with a roll clamp attachment.

[0002]

2. Description of the Related Art A forklift truck is an industrial vehicle for loading and unloading, which has a mast for raising and lowering loaded loads in front of a vehicle body so that it can be moved from place to place.

The forklift is provided with various attachments so that a good cargo handling work can be performed on each cargo depending on the shape and type of the cargo.
As one type of this attachment, there is a roll clamp which is useful when a cylindrical product, for example, a roll paper is held and lifted and transported.

FIG. 13 shows an example of a forklift equipped with a roll clamp. As shown in the figure, the lift cylinder 1 is fixed to a pair of left and right outer masts 2, and the pair of left and right inner masts 3 is moved up and down by using the outer mast 2 as a guide as the piston rod 1a expands and contracts. . The outer mast 2 is fixed to the vehicle body 7 in front of the vehicle body 7. As a result, as the inner mast 3 moves up and down, the lifting unit including the bracket 5 suspended on the chain and the roll clamp 4 that holds the load moves up and down.

The clamp cylinder 9 rotates the two clamp pieces 4c and 4d of the roll clamp 4 which rotates about the hinge portions 4a and 4b at the base end by the expansion and contraction of the piston rod 9a. The roll clamp 4 is opened and closed.

Working machine levers 10a, 10b, 10c, 1
0d and 10e are for controlling the operation of various cylinders through the controller 11 and the electromagnetic proportional control valve by the operator operating them, and are housed in the joystick box 14 together with the safety switch 13 for performing an emergency stop. There is.

Further, it has a rotary lever for hydraulically rotating the roll clamp 4 to the right or left while the roll paper is being held, and a hydraulic drive portion thereof. When the roll paper is stored, it is stacked vertically. On the other hand, when loading and unloading a truck, it is carried out with the horizontal grip. Therefore, the roll clamp 4 is mounted vertically (horizontal grip) and horizontally (horizontal grip). This is because it is necessary to rotate.

Therefore, as a work, for example, by supplying pressure oil from the electromagnetic proportional control valve to the clamp cylinder 9 by operating the working machine lever 10c, the roll clamp 4
It is possible to hold the cylindrical product by opening and closing the clamp pieces 4c and 4d, and lift it by operating the working machine lever 10a. Also, for example, the roll clamp 4 can be moved horizontally or vertically by operating the working machine lever 10d. It is rotated to load or unload trucks.

[0009]

However, in the forklift equipped with the roll clamp 4 described above, when the roll clamp 4 rotates, the operating device lever (rotating lever) is used.
Although the rotation speed and the rotation position are determined by the operation of 10d, it is difficult to operate with the lever output value with respect to the rotation lever angle (opening) as shown in FIG. 12, which requires skill. That is, when the vertical direction or the horizontal direction of the clamp is not reliable, the load applied to the bottom of the roll paper becomes uneven, and the roll paper may be damaged.

In the forklift, the clamped roll paper is placed on the ground or a table and the interlock for releasing the clamp is released when the chain of the mast is slackened. When rolling the roll paper caught laterally to the bed for loading, the clamp piece often hits the bed and damages the bed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide a control device for a forklift that accurately and efficiently sets a rotational speed and a rotational position.

A further object of the present invention is to provide a forklift control device that enables the loading of a truck or the like without trouble even if the roll paper is clamped.

[0013]

Means for Solving the Problems The structure of the present invention that achieves the above-mentioned object is as follows: (1) Control by a controller that has a roll clamp that can hold a cylindrical product from the outer peripheral surface and that is based on the operation of a rotary lever. In a control device for a forklift that rotates the roll clamp with a hydraulic motor via an electromagnetic control valve, an automatic switch and by turning on the automatic switch, the rotary lever is rotated in the same manner as the roll clamp separately from the operation. An interlocking detection switch that sequentially turns on the reed switches in each of speed-holding-deceleration-stop modes is arranged as an input device of the controller,

(2) A forklift having a roll clamp capable of holding a cylindrical product from the outer peripheral surface thereof, and rotating the roll clamp with a hydraulic motor via an electromagnetic control valve under the control of a controller based on the operation of a rotating lever. In the control device of (1), an automatic switch and an interlocking detection switch having a reed switch that shifts to an automatic deceleration mode and a stop mode in addition to the operation of the rotary lever when the automatic switch is turned on are arranged as an input device of the controller. Characterized by what was done, and

(3) The controller of the controller based on the operation of the opening / closing lever drives the clamp cylinder to hold the cylindrical product from the outer peripheral surface and has a roll clamp for releasing the holding, while the piston of the lift cylinder has a piston. In a control device for a forklift that suspends a chain by expanding and contracting a rod and elevates a bracket equipped with the roll clamp, a hydraulic sensor of the lift cylinder and an interlock release switch are connected to an input side of the controller. The controller is characterized in that the interlock of the roll clamp is released even when the high pressure is detected by the hydraulic pressure sensor 23 by turning on the interlock release switch.

[0016]

[Function] Regardless of the operation of the rotary lever, or in addition to the operation, at least the deceleration mode and the stop mode are executed by turning on the automatic switch, and the operation of the open / close lever is restored by the interlock release switch. .

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will now be described with reference to FIGS. 1 and 2 show a configuration of an embodiment, which is applied to a forklift having a roll clamp shown in FIG. 13, and is provided with a rotary lever 10d, an automatic switch 20, and an interlocking detection switch 21 on the input side centering on the controller 11. On the output side, left-hand and right-hand electromagnetic control valves 30 and 31 and an unload electromagnetic switching valve 32 are provided. Here, the controller 11 includes a clock 111, a CPU 112, an A / D converter 113, a solenoid valve drive circuit 114, a RAM 115, a ROM 116, a switch input interface 117, and a power supply circuit 118.
Consists of.

The rotary lever 10d is formed of, for example, a potentiometer, and a current value which is a lever output value shown in FIG. 12 and proportional to an operation amount is output to the controller 11 as a lever operation signal. This lever operation signal is A
It is converted into a digital signal by the / D converter 113 and sent to the CPU 112. In the CPU 112, RM
A115 realizes the functions described in various software stored in the ROM 116 and performs various calculations, and the calculation processing is synchronized with the clock of the clock generator 111. The solenoid valve drive circuit 114 is driven based on the calculation result of the CPU 112, and the flow rate control signal and the unload valve opening / closing signal are output to the hydraulic circuit including the solenoid control valves 30, 31 and the solenoid switching valve 32.

Further, in the controller 11, the switch input interface 117 is connected with the automatic switch 20 and the detection switch 21 which is interlocked with the automatic switch 20. This automatic switch 20 is provided on condition that there is no input from the rotary lever 10d when it is turned on.
Rotate the vertical grip of the roll clamp to the horizontal grip,
Alternatively, it has a function of rotating a horizontal grip into a vertical grip. When the automatic switch 20 is turned on, the roll clamp rotates to the right or left to rotate horizontally or vertically, and the interlocking detection switch 21 also rotates with this rotation. This interlocking detection switch 21 has four reed switches 211, 212, 213 for the magnet 210 in a fixed state.
When the automatic grasping switch 214 in the state of FIG. 1 is used to turn the horizontal grip into the vertical grip, the reed switch 211 detects the rotational speed. Inputting to the CPU 112 through the switch input interface 117, the acceleration, the constant speed (holding) of the rotation speed by the magnet detection of the reed switch 212, the deceleration by the detection of the reed switch 213, and the stop by the detection of the reed switch 214. To do. In this case, the reed switches 211, 212, 213, 21 are rotated when the roll clamp is rotated clockwise by the right grip.
When the interlocking detection switch 21 rotates in the order of 4 and rotates sideways by left rotation, the reed switches 214, 2
The interlocking detection switch 21 rotates in the order of 13, 212 and 211.

As a result, the roll clamp is automatically rotated by turning on the automatic switch 20 in addition to the operation of the rotary lever 10d, and the reed switch 213 or 21 is used.
By inputting 2, the deceleration mode is adopted, and the rotation speed and the rotation position can be easily and efficiently determined.

As shown in FIG. 2, the hydraulic circuit includes a hydraulic pump 301, electromagnetic control valves 30, 31, a hose reel 302,
It mainly has a hydraulic motor 303 for rotating the roll clamp, and further has a pilot hydraulic pressure relief valve 30 for the electromagnetic control valve.
4, a check valve 305, a relief valve 306, and an unload valve 32. When the electromagnetic control valve 30 or 31 is switched from the neutral position by a command from the controller 11, the oil flow is reversed and the roll clamp is rotated via the hydraulic motor 303. In this case, the interlocking detection switch 21 is rotated by the rotation of the worm gear 215 when the automatic switch 20 is turned on.

FIG. 3 shows a vertical or horizontal stop (right angle stop) control flow associated with the rotation of the roll clamp. First, after initialization, it is determined whether the operation of the rotary lever 10d is right rotation or left rotation, and in each case, the calculation is performed by the lever, and the output value is output from the lever value, and the output value is calculated by the electromagnetic control valves 30, 31. Output to. This is the rotary lever 1
This is rotation control of the roll clamp by operating only 0d. When there is no input from the rotary lever 10d and when the automatic switch 20 has already been turned on and is not in the automatic rotation mode, it is determined whether the automatic switch 20 is on or off. Output stop is set when the automatic switch 20 is not turned on. When the automatic switch 20 is turned on, it is determined whether the right rotation deceleration switch 213 is turned on or the right rotation stop switch 214 is turned on. If the automatic switch 20 is turned on, the left rotation automatic flag set in the reverse rotation is set. , The left speed increase flag is set, and the left initial value is set. Further, when the deceleration switch 213 for right rotation or the stop switch 214 is not on, it is determined whether the deceleration switch 212 for left rotation or the stop switch 211 is on. The speed flag is set and the right initial value is set. Normally, when the automatic switch is turned on, the switches 213, 214,
Since 212 and 211 are in the ON state, the flag setting and the initial value setting are performed, and then the right rotation automatic mode or the left rotation automatic mode is selected and the automatic control is performed.

FIG. 4 shows a right rotation automatic control flow in the automatic mode in FIG. 3, in which speed control is performed by discriminating between speed increase, constant speed (holding), deceleration, and stop by the reed switch. . At the start of the control flow, first, the reed switch 211 determines whether or not the speed increasing mode is set. In the speed increasing mode, the output value is obtained by adding the speed increasing value to the previous value. If it is larger than the constant speed value, the speed is further increased, and if it is larger, the speed increase flag is cleared and the holding flag is set to set the output value to the constant speed value.
If the speed increasing mode is not set, the reed switch 212 determines whether or not the holding mode is set, and the holding mode (constant speed mode)
In the case of, it is determined whether or not the deceleration switch has been turned on. If the deceleration switch 213 has not been turned on, the holding mode is maintained. If the deceleration switch is turned on, the holding flag is cleared and the deceleration flag is set. . If it is not in the holding mode, then the reed switch 213 determines whether or not it is in the deceleration mode. If the stop switch 214 has not been turned on in the deceleration mode, the deceleration mode is continued as it is and the deceleration is performed using the previous value-deceleration value as the output value. Then, in this deceleration mode, it is determined whether or not the output value is smaller than the fine speed value, and when it becomes smaller, the deceleration flag is cleared and the output value is set to the fine speed value. In this way, when the stop switch 214 is turned on in the deceleration mode, the automatic rotation flag is cleared and the output stop value is set. Next, when the stop switch 214 is turned on, the rotation automatic flag is reset and the output stop value is set. In this way, rotation with speed-holding-deceleration-stop is performed. 4 shows the automatic control flow for right rotation, but FIG. 5 shows the left rotation automatic control flow, and FIG. 5 is the same as FIG. 4 except that the left and right sides are switched.

Thus, in this embodiment, the automatic switch 2
By inserting 0, the mutual rotation of the vertical grip and the horizontal grip by the roll clamp can be automatically performed, and the introduction of the deceleration mode ensures the rotation of the roll clamp efficiently and with high accuracy, even if not an expert. it can.

In the above-described embodiment, when the automatic switch 20 is turned on, the horizontal grip and the vertical grip are automatically rotated and the deceleration mode is provided.
As another example, it is possible to detect whether the roll paper is held vertically or horizontally by turning on the automatic switch 20 and to automate the deceleration mode, and the rotation can be performed manually by the rotary lever 10d. That is, there is no automatic speed-up or constant-speed mode in FIG.
Only the switch 213 and the stop switches 211 and 214 are activated, and only the deceleration mode and the stop mode are activated.

The control flow shown in FIGS. 6 to 8 is executed in the so-called semi-automatic mode consisting only of deceleration / stop, not in the fully automatic mode consisting of such acceleration / constant speed / deceleration / stop. In this semi-automatic mode, since the operation by the rotary lever 10d is the main operation, the roll clamp is rotated by the rotary lever 10d regardless of the closing of the automatic switch 20, but when the automatic switch 20 is closed, the rotary lever by the operator is turned on. Regardless of the operation of 10d, the deceleration mode is set at the deceleration position and the shockless mode is reached to stop. In this case, in order to perform restart and fine adjustment, in the stop region in the neutral region of the rotary lever 10d, the right start flag is set by turning on the right stop switch 214 and the left stop switch 211 is turned on as shown in FIG. The left start flag is set, and the start flag is cleared when the stop switches 214 and 211 are not in the ON state.

FIG. 7 shows a control flow of the right rotation lever. The opening degree of the rotary lever is calculated in accordance with the control circuit of the rotary lever 10d. In this case, it is determined whether the automatic switch 20 is on or off. Automatic switch 2
When 0 is in the off state, control is performed only by the lever 10d.
When the automatic switch 20 is turned on, it is determined whether or not the right stop switch is on and the right start flag is present. When the stop switch 214 is not in the on state, it is determined whether the deceleration switch 213 is on or off. It When the deceleration switch 213 is turned on, the deceleration mode is set. Here, when the rotary lever value is smaller than the fine speed value, the output value is the lever value, and when it is not smaller than the fine speed value, it is determined whether or not the holding mode. When the mode is not the holding mode, the output value is the previous value minus the deceleration value and gradually decreases the speed. When the output value is smaller than the slow speed value, the holding flag is set and the slow speed value is set as the output value. By setting this holding flag, the slow speed holding mode is set. When the stop switch 214 is turned on after the deceleration mode, the hold flag is cleared and the output stop value is set. This stop switch 2
Since the right start flag is set by turning on 14,
When the stop switch is turned on, the start flag is set, but when the stop switch is turned off and the right start flag is cleared, the restart is performed to eliminate the positional deviation. Although FIG. 7 shows a right lever control flow, the left lever control flow of FIG. 8 is different from that of FIG. 7 only in the left and right levers, and the flow itself does not change.

Thus, in the semi-automatic mode, deceleration and stop can be automatically performed by turning on the automatic switch 20, and the shockless mode can be accurately stopped.

FIG. 9, FIG. 10 and FIG. 11 show the structure for interlocking and releasing the roll clamp. Figure 9
In the above, as the input of the controller 11, the clamp opening / closing lever 10c and the hydraulic pressure sensor 2 of the lift cylinder 1 are used.
3, an interlock release switch 22 is provided, and outputs include a vertical control electromagnetic control valve 40 of the lift cylinder 1, a roll clamp opening / closing electromagnetic control valve 41, and an unload switching valve 42. Further, in the hydraulic circuit in FIG. 10, there is an electromagnetic control valve 40 that controls the lifting and lowering of the lift cylinder 1, and an electromagnetic control valve 41 that controls the opening and closing of the clamp cylinder 9 of the roll clamp via the hose reel 402. Exists. In addition to the unload valve 42,
There is a relief valve 406, a check valve 405, a pilot relief valve 406, and a clamp relief valve 407. The hydraulic pressure of the lift cylinder 1 is detected by the hydraulic pressure sensor 2
It is detected in 3 to detect whether the roll paper is being conveyed, the opening / closing lever 10c outputs a clamp command, and the interlock release switch 22 outputs an interlock release command. When the electromagnetic control valve 41 is driven through the controller 11 by operating the opening / closing lever 10c, the roll paper is clamped, and when the electromagnetic control valve 40 is driven by a command from the controller 11, the lift cylinder 1 lifts the roll paper. Interlock works at. This interlock is released when the roll paper is grounded and the bracket supporting chain by the lift cylinder 1 is slackened to prevent accidental release of the clamp during transportation. The hydraulic sensor 23 determines whether the roll paper is being transported. That is, when the hydraulic pressure sensor 23 detects that the roll paper is being conveyed, the controller 11 closes the command of the open / close lever 10c.
Is working. However, when the roll paper is loaded onto the truck by the horizontal grip, it is necessary to release the interlock and roll the roll paper even if the hydraulic pressure sensor 23 detects the load. Is provided with an interlock release switch 22.

FIG. 11 shows an interlock release control flow. The output stop value is set when the lever is in the neutral position according to the judgment of the clamp opening / closing, and the clamp closing lever value is calculated to judge the clamp output. Give out. If the interlock release is not turned on even if the clamp open command is issued, the clamp open command is closed by detecting the hydraulic pressure above a certain load or detecting the chain tension.
When the clamp open command is issued and the interlock release command is issued, or when the hydraulic pressure falls below a certain value, the clamp is opened and the open output value is output.

In this way, the horizontal stacking work can be made efficient by the forced interlock release without damaging the truck.

[0032]

As described above, according to the present invention, the automatic rotation of the roll clamp and the adoption of the deceleration mode enable the rotational position to be set accurately and efficiently without any skill, and also the rotation of the roll clamp. The same applies when the deceleration / stop mode, which is semi-automatic, is adopted. In addition, the interlock can be released so that the horizontal stacking work can be efficiently performed.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram showing a hydraulic system.

FIG. 3 is a flowchart of a roll clamp automatic right-angle stop control.

FIG. 4 is a right rotation automatic control flowchart.

FIG. 5 is a left rotation automatic control flowchart.

FIG. 6 is a roll clamp semi-automatic right-angle stop control flowchart.

FIG. 7 is a right lever control flowchart.

FIG. 8 is a left lever control flowchart.

FIG. 9 is a configuration diagram of an embodiment of interlock release.

FIG. 10 is a diagram showing a hydraulic system.

FIG. 11 is a roll clamp interlock release control flowchart.

FIG. 12 is a characteristic diagram of a lever output value with respect to a lever opening.

FIG. 13 is an overall configuration diagram of an example of a forklift.

[Explanation of symbols]

 1 Lift Cylinder 4 Roll Clamp 5 Bracket 9 Clamp Cylinder 10c Opening / Closing Lever (Working Machine Lever) 10d Rotating Lever (Working Machine Lever) 11 Controller 20 Automatic Switch 21 Interlocking Detection Switch 22 Interlock Release Switch 23 Hydraulic Pressure Sensor 211, 212, 213, 214 Reed switch 30,31 Electromagnetic control valve 40,41 Electromagnetic control valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsuruji Kitabayashi 3,000, Tana, Sagamihara-shi, Kanagawa M / E / I Sagami High-Tech Co., Ltd.

Claims (3)

[Claims] 1. A forklift having a roll clamp capable of holding a cylindrical product from the outer peripheral surface thereof and rotating the roll clamp by a hydraulic motor via an electromagnetic control valve under the control of a controller based on the operation of a rotary lever. In the control device, the automatic switch and the reed switch for each of the speed increasing-holding-decelerating-stop modes are sequentially turned on by rotating the automatic lever in the same manner as the roll clamp in addition to the operation of the rotary lever. A forklift control device, characterized in that an interlocking detection switch and is arranged as an input device of the above controller. 2. A forklift having a roll clamp capable of holding a cylindrical product from the outer peripheral surface thereof, and rotating the roll clamp by a hydraulic motor via an electromagnetic control valve under the control of a controller based on the operation of a rotary lever. In the control device, an automatic switch and an interlocking detection switch having a reed switch that shifts to the automatic deceleration mode and the stop mode in addition to the operation of the rotary lever when the automatic switch is turned on are arranged as the input device of the controller. A forklift control device characterized by the above. 3. A piston rod of a lift cylinder, which has a roll clamp for driving the clamp cylinder to hold the cylindrical product from the outer peripheral surface and releasing the holding under the control of the controller based on the operation of the opening / closing lever. In a control device for a forklift that suspends the chain by expansion and contraction and raises and lowers the bracket equipped with the roll clamp, connect the hydraulic sensor of the lift cylinder and the interlock release switch to the input side of the controller. A forklift controller, wherein the controller is configured to release the interlock of the roll clamp even when a high pressure is detected by the hydraulic pressure sensor by turning on a lock release switch.