JPH0676297U - Forklift cargo handling control device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a cargo handling control device for a forklift capable of optimally synchronizing the amount of movement between the face and the vehicle body [Configuration] The amount of movement of the face 9 equipped with the push-pull device 2 And a movement amount of the vehicle body 1 are respectively provided with a synchronous switch 16 for instructing synchronous movement in opposite directions. When the synchronous switch 16 is turned on, the operation amount of the accelerator 15 is used as a movement instruction for the face 9. Since it has a control unit capable of controlling, the synchronization control with the vehicle body can be performed within the limit of the moving speed of the face 9, so that the synchronism is good, the workability is improved, and as a result, the operation amount of the accelerator is almost the same. Proportional running speed is obtained and driving feeling is not impaired.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a forklift cargo handling control device capable of optimally synchronizing the amount of movement between a face and a vehicle body.

[0002]

[Prior art]

 Conventionally, as illustrated in FIG. 5, in a forklift equipped with a push-pull device A, the face 9 is automatically fed in and out and the amount of movement of the vehicle body 1 is controlled in synchronization with each other to improve workability. A cargo handling control device is known.

In such an automatic cargo handling control device, when the operator operates the accelerator 15 to move the vehicle body 1 forward while the synchronous switch 16 provided near the driver's seat is turned on, the load W is placed. After clamping the end portion of the formed sheet pallet 12 with the sheet gripper 11 and the jaw 19 provided on the lower portion of the face 9, the face 9 is made equal to the vehicle speed based on the deviation of the moving amount from the vehicle 1. It controls the feeding so that the speed is maintained.

[0004]

[Problems to be solved by the device]

 However, it is usually difficult to increase the moving speed of the face up to the maximum speed of the vehicle body. Therefore, the vehicle body 1 travels based on the operation amount input by the accelerator 15 as in the conventional case, and the traveling speed becomes In the case where the face 9 is pulled in based on this, if the traveling speed of the vehicle body is high, there is a problem that the moving speed of the face 9 cannot keep up with this and the two cannot be synchronized.

The present invention has been devised in view of the above situation, and an object thereof is to provide a cargo handling control device for a forklift capable of optimally synchronizing the movement amounts of the face and the vehicle body.

[0006]

[Means for Solving the Problems]

 The present invention is directed to a forklift equipped with a push-pull attachment at the front of the forklift, which has a face that can be retracted and extended along the platen and a seat gripper that can clamp the sheet pallet under the face. The cargo handling control device includes a synchronous switch for issuing a synchronous movement command in opposite directions of the movement amount of the face and the movement amount of the vehicle body, and when the synchronization switch is turned on, the operation amount of the accelerator Is a cargo handling control device for a forklift, which comprises a control unit capable of giving a movement command for the face.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of the whole of the present invention. A forklift body 1 is provided with a mast device 3 standing upright in front of the forklift, and a mast device 3 is provided with a lift cylinder capable of moving up and down by a lift cylinder. 4 is installed.

A push-pull device 2 is attached to the front surface of the elevating frame 4, and the push-pull device 2 includes a frame 7 and a platen 8 extending forward from a lower portion of the frame 7. And a face 9 attached along the platen 8 via a pantograph-shaped link mechanism 6 which can be drawn in and out, and a sheet gripper 11 provided below the face 9.

A piston rod of a hydraulic cylinder 5 is pivotally attached to the link mechanism 6 so that the link mechanism 6 can be moved back and forth. Further, the sheet gripper 11 is actuated by the expansion and contraction of the piston rod of the hydraulic cylinder 10, and the sheet gripper 11 and the jaw 19 having a substantially U-shaped cross section can clamp one end of the sheet pallet 12.

Further, in this example, one end of the wire 13 is fixed to the face 9, and the other end of the wire 13 is fixed to the reel type face movement amount detecting unit 14 mounted on the frame 7. Thereby, the amount of movement of the face 9 with respect to the vehicle body 1 can be detected.

Further, the sheet gripper 11 is provided with a clamp detection unit (not shown), and the clamp detection unit is an optical sensor including a light emitting unit and a light receiving unit, each of which is a sheet gripper. 11, the sheet pallet 12 attached to the jaw 19 can detect that the sheet gripper 11 clamps the sheet pallet 12 by blocking the search light.

In the vehicle body 1 of a forklift, an accelerator 15 that outputs a travel command and a synchronization switch 16 that outputs a push-pull synchronization command are usually provided near the driver's seat and on the drive shafts of the running wheels. Is provided with a vehicle body movement amount detector 18 for detecting the amount of movement of the vehicle body.

Next, an electrical block diagram of the present invention will be described with reference to FIG. The control unit 22 is normally input with an accelerator 15 that outputs a vehicle body travel command, a synchronization switch 16 that outputs a synchronization command of the push-pull device 2, and an operation signal of the cargo handling operation lever 17, respectively.

Further, the movement amount signals of the face movement amount detection unit 14 capable of detecting the movement amount of the face 9 and the vehicle body movement amount detection unit 18 capable of detecting the movement amount of the vehicle body are input to the comparator 20, respectively. Then, the comparator 20 outputs a deviation signal to the control unit 22.

Based on these input signals, the control unit 22 outputs a predetermined chopper conduction ratio to the traveling electric motor switching unit 23 and the hydraulic electric motor switching unit 25 according to the procedure stored in advance in the storage unit 21, As a result, the drive motor 24 and the hydraulic motor 26 are drive-controlled. The control unit 22 outputs an excitation signal to the solenoid 27 of the solenoid valve 28 described later.

FIG. 3 shows a hydraulic circuit diagram of the push-pull device, in which the hydraulic electric motor 26 is rotationally driven to discharge the pressure oil by the pump P, and the seat gripper 11 is moved through the solenoid valve 28. It is sent to the hydraulic cylinders 10 and 10 for moving up and down and the hydraulic cylinder 5 for moving the face 9 forward and backward.

[0017]

[Action]

 The operation of the present invention configured as above will be described based on the flowchart of FIG. First, the operator determines whether or not the accelerator operation is performed (step 1). When the accelerator operation is performed (Y in step 1), it is determined whether or not the synchronous switch 16 is turned on (step 2). ).

When the synchronous switch 16 is not turned on, the chopper conduction ratio proportional to the depression angle of the accelerator 15 is output to the traveling motor switching unit 24 as in the usual case (step 8).

When the synchronous switch 16 is turned on (Y in step 2), the direction is detected (step 3). This can be detected by a direction switch (not shown) in the case of a counterbalance type forklift, or directly from the accelerator lever in the case of a reach type.

Here, when the accelerator operation is trying to move the vehicle body forward (Y 3 in step 3), an excitation signal is output to the solenoid 27 in order to switch the solenoid valve 28 to the port A (step 4).

Next, the chopper conduction ratio proportional to the accelerator 15 is output to the hydraulic motor switching unit 25 (step 5), and the hydraulic motor 26 is driven. That is, the operation amount of the accelerator 15 is not a command to the traveling electric motor 24 for traveling the vehicle body 1 but a command to the hydraulic electric motor for extending and contracting the hydraulic cylinder 5 for moving the face 9 back and forth. Become. Further, the oil flow rate is controlled by changing the chopper conduction ratio of the hydraulic motor 26, not the flow control valve.

At this time, since the solenoid valve 28 is switched to the port A, the hydraulic cylinder 5 is contracted by the hydraulic oil sent from the pump P so that the face 9 is drawn to the vehicle body 1 side.

Next, the deviation between the movement amount of the vehicle body 1 and the movement amount of the face 9 is calculated by the comparator 20 (step 6), and based on this, the chopper conductivity is output to the traveling motor switching unit 23. Then, the traveling electric motor 24 is driven, and the process returns to step 1 to repeat the processing.

When the accelerator operation is going to move the vehicle body backward (N in step 3), an excitation signal is output to the solenoid 27 in order to switch the solenoid valve 28 to the port B (step 9). The hydraulic cylinder 5 is extended.

The required speed, the required acceleration, the chopper conductivity, and the like based on the deviation obtained in step 6 may be stored in the storage unit 21 in advance.

As described above in detail, according to the present invention, when the synchronous switch 16 is turned on, the accelerator command is the speed instruction for the face feeding and the face feeding, and the face velocity determined by this is used as a reference. The speed of the car body is controlled.

[0027]

[Effect of device]

 According to the present invention, since the face and the vehicle body can be synchronously controlled within the limit of the moving speed of the face, the synchronism is good and the workability is improved. As a result, a running speed almost proportional to the accelerator operation amount is obtained, and the driving feeling is not impaired. Moreover, in the past, when the running resistance changed abruptly, the vehicle speed also changed abruptly, which caused hunting, but since the face speed is not easily affected by external disturbances, such a situation can be prevented. .

[Brief description of drawings]

FIG. 1 is an overall side view of an embodiment of the present invention.

FIG. 2 is an electrical block diagram of an embodiment of the present invention.

FIG. 3 is a hydraulic circuit diagram of a push-pull device.

FIG. 4 is a flowchart of an embodiment of the present invention.

FIG. 5 is an overall side view of a conventional push-pull device.

[Explanation of symbols]

 1 vehicle body 2 push-pull device 9 face 14 face movement amount detection unit 15 accelerator 16 synchronization switch 18 vehicle body movement amount detection unit 20 comparator 22 control unit

Claims (1)

[Scope of utility model registration request] 1. A forklift loading and unloading machine equipped with a push-pull attachment equipped with a face that can be retracted and extended along a platen and a sheet gripper that can clamp a sheet pallet at the lower part of the face, at the front of the forklift. The controller is provided with a synchronous switch for instructing synchronous movement in opposite directions of the movement amount of the face and the movement amount of the vehicle body, and when the synchronization switch is turned on, the operation amount of the accelerator is changed. A cargo handling control device for a forklift, comprising a control unit capable of issuing a movement command for the face.