JP3578332B2 - Cargo handling vehicle - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cargo handling vehicle such as a forklift.
[0002]
[Prior art]
Some forklifts as general cargo handling vehicles have a configuration as shown in FIG. 3 and are called counterbalance type. In this forklift, a fork 21 which is a carrier on which a load is placed and a mast 22 which is a support for guiding the fork 21 to move up and down are disposed at a front position, and at a rear position. The vehicle has a vehicle body 24 on which a counter weight 23 is provided. At this time, a hydraulic cylinder 25 is provided upright along the mast 22 which supports the fork 21 so as to be able to move up and down. The fork 21 is moved up and down by an elevating device (not shown) using the hydraulic cylinder 25 as an actuator. It is to be made.
[0003]
Further, a running motor 26 is provided inside the vehicle body 24, and the running body 26 itself, that is, the forklift itself is moved forward and backward along the front-rear direction by a running device (not shown) using the running motor 26 as an actuator. And it is to be turned. On the driver's seat panel 27 of the vehicle main body 24, various operation levers including a lift lever 28 which is manually operated when the fork 21 is moved up and down are arranged. A controller 29 configured using a computer is provided, and the controller 29 comprehensively controls operations of a lifting device, a traveling device, and the like, and operations associated with them.
[0004]
[Problems to be solved by the invention]
By the way, by using this kind of forklift, the loading operation and the unloading operation on the rack shelf 30 after the fork 21 is raised are to be executed. After placing the palletized luggage 31 on the fork 21 inserted into the rack shelf 30 with the forward movement of the vehicle body 24, the fork 21 is racked with the backward movement of the vehicle body 24. The lowering operation is performed after the reciprocating operation is performed to the outside of the shelf 30.
[0005]
However, a lift bracket (not shown) attached to the base end of the fork 21 and a backrest 32 are interposed between the operator sitting on the vehicle body 24 and the fork 21, so that the operator can It is difficult to visually confirm the retreat operation of the fork 21. Further, since the rack shelf 30 is usually installed in a dim warehouse, it is also difficult to visually recognize that the fork 21 has reached the outside of the rack shelf 30. Since the fork 21 is brought into contact with the rack shelf 30 due to the lowering operation of the fork 21, the load collapses, and the load 31 may drop.
[0006]
The present invention has been made in view of such inconvenience, and an object of the present invention is to provide a cargo handling vehicle configured to effectively prevent a fork during a descending operation from contacting a rack shelf.
[0007]
[Means for Solving the Problems]
Cargo handling vehicle according to claim 1 of the present invention, a loading platform which baggage is placed, a lifting device for vertical movement of the loading platform, and a vehicle body to which the loading platform and the lifting device are disposed, distribution to the vehicle body is set to a cargo handling vehicle comprising a running device for advancing and retracting operation of the vehicle body itself, and the lowering operation instructing means for instructing the loading platform of the lowering operation, the moving distance measuring means for measuring the reverse distance of the vehicle body And after the lowering operation instructing means instructs the lowering operation of the carrier, the retreat distance of the vehicle body measured by the moving distance measuring means exceeds a set distance which is set by adding the total length of the carrier and the surplus distance. until prohibits bed of descending operation, and finger and operation control means for performing control to lower operating loading platform with at the time the reverse distance of the vehicle body exceeds the set distance, the execution of the control by the operation control means Characterized in that it comprises a control execution instructing means for.
[0008]
Cargo handling vehicle according to claim 2 of the present invention are those according to claim 1, wherein the control execution instructing means, a vehicle body in which the loading platform is raised operating to over the predetermined height has started to retreat operation is characterized by having at is an indication of the execution of control by the operation control means.
[0009]
A cargo handling vehicle according to a third aspect of the present invention is the cargo handling vehicle according to the first or second aspect, wherein the operation control unit determines that the retreat distance of the vehicle main body measured by the moving distance measurement unit is equal to the total length of the carrier. The reverse movement of the vehicle body is stopped at a point in time when the sum exceeds the set distance and the set distance is exceeded.
[0010]
Cargo handling vehicle according to Claim 4 of the present invention are those described in any one of claims 1 to 3, which comprises a notification means or alarm means for notifying an execution state of the control by the operation control means It is characterized by the following.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, it is assumed that a cargo handling vehicle is a forklift. However, the cargo handling vehicle is not limited to only a forklift, and a cargo bed on which a load is placed, an elevating device for elevating the cargo bed, a vehicle body on which the loading platform and the elevating device are arranged, and Needless to say, a cargo handling vehicle other than a forklift may be used as long as it is a cargo handling vehicle provided with a traveling device disposed on the vehicle main body to move the vehicle main body itself.
[0012]
FIG. 1 is a block diagram showing a main part of a control system provided in the forklift according to the present embodiment, and FIG. 2 is a flowchart showing the control operation. It should be noted that the forklift according to the present embodiment is of a counterbalance type, and its overall structure is basically not different from the conventional embodiment shown in FIG. Will be described with reference to FIG.
[0013]
As shown in FIGS. 1 and 3, the forklift according to the present embodiment has a fork 21 serving as a carrier on which palletized luggage 31 is placed and a mast serving as a support for guiding the fork 21 to move up and down. 22 is disposed at a front position, and a vehicle body 24 having a counterweight 23 disposed at a rear position. A hydraulic cylinder 25 is provided upright along a mast 22 that supports the fork 21 so as to be able to move up and down. The hydraulic cylinder 25 is used as an actuator, and the elevating device 1 disposed inside the vehicle body 24, The fork 21 is to be moved up and down while being guided by the mast 22 as the elevating device 1 of the system is operated. In addition, the height position of the fork 21 that has moved up is detected by using the lift detecting means 2 such as a reel potentiometer or a magnet sensor.
[0014]
A traveling motor 26 that can rotate forward and reverse is disposed inside the vehicle body 24. Depending on the electric traveling device 3 that uses the traveling motor 26 as an actuator, the vehicle body 24 itself, that is, the forklift itself is used. It is to be moved forward and backward along the front-rear direction and to be turned. The forward distance S1 and the backward distance S2 of the vehicle body 24 that is moving forward and backward are determined by an up-down type measuring instrument that counts up the forward distance S1 of the vehicle body 24 and down-counts the backward distance S2, or a rotary encoder. Is measured after using the moving distance measuring means 4 using the following method. Note that the forward distance S1 of the vehicle body 24 is based on the stop position of the vehicle body 24 stopped immediately before the fork 21 is inserted into the rack shelf 30, and the retreat distance S2 is that the fork 21 is placed on the rack shelf 30. The origin is set to the stop position of the vehicle body 24 that is stopped with the luggage 31 inserted and loaded.
[0015]
Further, the driver's seat panel 27 provided in the forklift according to the present embodiment is manually operated when the fork 21 is moved up and down, and also functions as a descending operation instructing means 5 for instructing the fork 21 to descend. A plurality of operation levers including a lift lever 28 to be operated, that is, various operation levers used when operating the elevating device 1 and the traveling device 3 are arranged. The lift lever 28 functioning as the lowering operation instructing means 5 outputs an ON signal in accordance with a manual operation when the fork 21 is lowered, and the ON signal output from the lift lever 28 will be described later. Controller 6 is input. Although not shown, a brake and an accelerator used for operating the traveling device 3 are arranged at the foot positions of the driver's seat panel 27, respectively.
[0016]
The driver's seat panel 27 is provided with a notifying means 7 and a warning means 8 such as a liquid crystal display and a buzzer for notifying an operator of a control execution state and the like. A switch functioning as control execution instructing means 9 for instructing execution of the control to be prohibited is provided, and the ON signal output from this control execution instructing means 9, that is, control for inhibiting the fork 21 from descending is executed. An ON signal indicating an instruction to that effect is also input to the controller 6. If the ON signal output from the control execution instructing means 9 is input to the controller 6 simultaneously with the ON signal output from the lift lever 28 as the descending operation instructing means 5, the moving distance measurement is performed. The means 4 measures the forward distance S1 and the reverse distance S2 of the vehicle body 24.
[0017]
Furthermore, a controller 6 configured by using a microcomputer is provided inside the driver's seat panel 27 at this time, that is, a controller for comprehensively controlling the operation of each device and the cooperative operation of various devices. The controller 6 has a configuration including a memory unit 10 such as a ROM or a RAM for storing various data and an arithmetic processing unit 11 including a CPU. The memory unit 10 constituting the controller 6 has a margin A measured beforehand, that is, the tip of the fork 21 and the rack shelf 30 when the fork 21 has reliably moved out of the rack shelf 30. The set distance [L + A] set by adding the margin distance A to be secured to the outer surface of the fork 21 and the total length L of the fork 21 itself is stored in advance as data.
[0018]
On the other hand, the arithmetic processing unit 11 of the controller 6 determines that the retreat distance S2 of the vehicle body 24 measured by the moving distance measuring means 4 is the sum of the set distance [L + A], that is, the total length L of the fork 21 and the allowance distance A. The fork 21 is prohibited from descending until the set distance [L + A] is exceeded, and the fork 21 is lowered when the retreat distance S2 of the vehicle body 24 exceeds the set distance [L + A]. It is to function as operation control means for executing. Therefore, as shown in FIG. 1, various kinds of operation signals are sent to the controller 6 from the lift detecting means 2, the moving distance measuring means 4, the lowering operation instructing means 5 which is a lift lever 28, and the control execution instructing means 9, respectively. And a detection signal are input, and signals instructing these operations are output from the controller 6 to each of the elevating device 1, the traveling device 3, the notification means 7, and the alarm means 8.
[0019]
By the way, the arithmetic processing unit 11 at this time prohibits the descending operation of the fork 21 until the retreat distance S2 of the vehicle body 24 exceeds the set distance [L + A], and the retreat distance S2 exceeds the set distance [L + A]. Although the control for lowering the fork 21 is executed at the time, a function for automatically stopping the retreat operation of the vehicle body 24 at the time when the retreat distance S2 of the vehicle body 24 exceeds the set distance [L + A]. Of course, it may have. In the present embodiment, the control execution instructing means 9 is turned on by manual operation. However, the present invention is not limited to manual operation, and it is assumed that the fork 21 is at a height position equal to or higher than a predetermined height. When the vehicle body 24 starts a retreating operation while the fork 21 is moving up to a predetermined height or higher automatically by using the lift detecting means 2 for detecting the lift-on operation. It is also possible to adopt a configuration in which the arithmetic processing unit 11 that has determined that the operation is the unloading operation based on this fact automatically determines that the execution of the control has been instructed.
[0020]
Next, a control operation at the time of unloading work performed by the forklift according to the present embodiment will be described based on the flowchart shown in FIG. Here, only the control at the time of the loading operation by the forklift is described, but the control at the time of the loading operation is basically the same as that at the time of the loading operation, and therefore the description is omitted.
[0021]
First, the operator at the time of the unloading operation moves the vehicle body 24 close to the front of the rack shelf 30 where the unloading operation is to be performed, then moves the vehicle body 24 forward, and then moves the fork 21 to the rack. Insert it into the shelf 30. Then, the operator who lifts the fork 21 slightly and places the luggage 31 on the fork 21 releases the brake forcibly stopping the operation of the traveling device 3 (step 1), and then lowers the fork 21. The control execution instructing means 9 for instructing execution of the control for inhibiting the operation, that is, the control execution instructing means 9 disposed on the driver's seat panel 27 as a switch is turned on (step 2). The height position of the fork 21 that has been raised when the fork 21 is inserted into the rack shelf 30 is detected by the lift detecting means 2.
[0022]
Subsequently, the operator manually operates the lift lever 28 functioning as the lowering operation instructing means 5 toward the lowering operation side of the fork 21 (step 3). Then, an ON signal is output from the lift lever 28 serving as the lowering operation instructing means 5, and an ON signal from the lowering operation instructing means 5 and an ON signal from the control execution instructing means 9 are sent to the controller 6. And enter. Then, the arithmetic processing unit 11 of the controller 6 to which the ON signal is input shifts to control for inhibiting the lowering operation of the fork 21 (step 4). At this time, the arithmetic processing unit 11 sends the traveling device 3 , An instruction signal to start the backward movement of the vehicle body 24 is output.
[0023]
As a result, the vehicle body 24 is moved backward by the traveling device 3 instructed to move backward, and the fork 21 is also moved backward together with the vehicle body 24 (step 5). Therefore, the moving distance measuring means 4 measures the retreat distance S2 of the vehicle body 24, and the arithmetic processing unit 11 of the controller 6 measures the moving distance measuring means 4 while prohibiting the fork 21 from descending. It is continuously determined whether or not the retreat distance S2 of the vehicle body 24 has exceeded a set distance [L + A] set by adding the total length L of the fork 21 and the allowance A (step 6).
[0024]
When the arithmetic processing unit 11 determines that the retreat distance S2 of the vehicle main body 24 has exceeded the set distance [L + A], the arithmetic processing unit 11 instructs the traveling device 3 to perform the retreat operation of the vehicle main body 24. An instruction signal to stop is output, and the retreating operation of the fork 21 and the vehicle body 24 is stopped (step 7). That is, the arithmetic processing unit 11 has a function of stopping the retreating operation of the vehicle main body 24 when the retreat distance S2 of the vehicle main body 24 exceeds the set distance [L + A].
[0025]
At the same time, the control for inhibiting the lowering operation of the fork 21 is released in the arithmetic processing unit 11 of the controller 6 (step 8), and the lowering operation of the fork 21 is performed from the arithmetic processing unit 11 to the lifting device 1. Is output. Then, since the lift lever 28 has already been manually operated to the lowering operation side, the fork 21 is continuously lowered by the lifting device 1 to which the instruction signal has been input (step 9). That is, the arithmetic processing unit 11 at this time has a function of lowering the fork 21 when the retreat distance S2 of the vehicle body 24 exceeds the set distance [L + A].
[0026]
Although a detailed description is omitted in the present embodiment, when the prohibition of the lowering operation of the fork 21 is released, the notification unit 7 is used to notify the operator of the release. It is preferable that the alarm means 8 be configured to issue an alarm to the operator when the operator attempts to lower the fork 21 by manual operation during execution of the control for inhibiting the downward movement of the fork 21. When such a configuration is employed, the advantage that erroneous determination by the operator hardly occurs is ensured.
[0027]
【The invention's effect】
As described above, in the cargo handling vehicle according to the present invention, the lowering operation of the carrier is prohibited until the retreat distance of the vehicle body exceeds the set distance that is set by adding the total length of the carrier and the allowance distance. When the retreat distance exceeds the set distance, the bed is lowered. Therefore, the loading platform during loading and unloading operations will move out of the rack shelves, reach a safe position, and be immediately moved down. There is no occurrence of contact with the rack shelves or occurrence of load collapse due to such contact, and the effect that these inconveniences are reliably and effectively prevented can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a main part of a control system provided in a forklift according to the present embodiment.
FIG. 2 is a flowchart showing the control procedure.
FIG. 3 is a side view showing the overall structure of a forklift according to the present embodiment and a conventional form.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 lifting device 3 traveling device 4 moving distance measuring means 6 controller 7 reporting means 8 warning means 9 control execution instructing means 11 arithmetic processing unit (operation control means)
21 Fork (packing bed)
24 Vehicle main body S2 Retraction distance L of vehicle main body Total length A of fork (packing bed) Extra distance

Claims (4)

A loading platform luggage is placed, a lifting device for vertical movement of the loading platform, the loading platform and the lifting device and the vehicle body is disposed is traveling device for advancing and retracting operation of the vehicle body itself is disposed on the vehicle body A cargo handling vehicle comprising:
And lowering operation instructing means for instructing the loading platform of the lowering operation, a moving distance measuring means for measuring the reverse distance of the vehicle body, after the loading platform of the lowering operation is instructed by the lowering operation instructing means, the moving distance measuring means Until the retreat distance of the vehicle body measured by the above exceeds the set distance that is set by adding the total length of the luggage and the allowance distance, the lowering operation of the luggage body is prohibited, and the retreat distance of the vehicle body exceeds the set distance. cargo handling vehicle, characterized in that it comprises an operation control means for performing control to lower operating loading platform with at this point, and a control execution instruction means for instructing the execution of the control by the operation control means. The control execution instructing means, and wherein said loading platform is for instructing the execution of control by the operation control means with at the time when the vehicle body has risen operates to over the predetermined height has started to retreat operation The cargo handling vehicle according to claim 1. The operation control means stops the retraction operation of the vehicle body at a point in time when the retreat distance of the vehicle body measured by the moving distance measurement means exceeds a set distance that is set by adding the total length of the carrier and the allowance distance . The cargo handling vehicle according to claim 1 or 2, wherein the cargo handling vehicle is a vehicle. The cargo handling vehicle according to any one of claims 1 to 3, further comprising a notifying unit or an alarming unit for notifying an execution state of the control by the operation control unit.

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