JP3120404B2 - forklift - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forklift.

[0002]

2. Description of the Related Art FIG. 4 is a partial longitudinal sectional view showing a state where a pallet is scooped by a conventional forklift.
In this figure, reference numeral 1 denotes a forklift, and the forklift 1 has two L-shaped forks 21 and 22 on a vehicle body.
And a fork mounting portion 20 for mounting the forks 21 and 22 and a mast 23 for raising and lowering the forks. Reference numerals 30 to 33 denote pallets on which cargo is loaded.

The forklift 1 has a fork 2
After inserting the pallets 30 between the horizontal frames 30a, 30b and the floor with the lower parts 1, 22 lowered to the lower end,
By lifting the forks 21, 22, the stacked pallets 30, 32 can be lifted via the horizontal frames 30a, 30b, and the cargo handling operation can be performed.

[0004]

However, in the conventional forklift 1, as shown in FIG. 4, the forks 21 and 22 are excessively inserted and
May pass through the pallet 30 and reach the position of the horizontal frame 31a of the pallet 31 at the back. In this case, if the forks 21 and 22 are raised as it is, the pallet 31 on the back and the pallet 33 placed thereon are greatly inclined as shown by the phantom line in the figure, which is extremely dangerous.

On the contrary, fork tips 21a, 22a
If the pallet 30 does not reach the horizontal frame 30b on the back side of the pallet 30 on the front side, the pallet 30 and the pallet 32 placed thereon are greatly inclined, which is also very dangerous. Therefore, the operator always keeps the tips 21a, 22a of the forks at the front pallet 3 so that this situation does not occur.
It is necessary to check with extreme caution that it reaches the frames 30a and 30b of the pallet 31 and does not reach the frame 31a of the pallet 31 at the back. There was a drawback that it was easy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and when a pallet is picked up by a forklift, it is possible to easily prevent a danger caused by a forklift of a forklift being too deep or too shallow. It aims to provide forklifts.

[0007]

That is, in the present invention,
A detector for checking the distance from the pallet is provided at the fork mounting portion of the forklift, and the distance between this detector and the pallet is obtained by subtracting the depth of the pallet from the length of the fork .
Multiple preset values within the range of the optimal distance determined from the numerical values
A circuit, and a detection signal of the detector is selected by one of the circuits.
A changeover switch for selectively supplying power,
The distance between the pallet detected by output device is the
Preset to the circuit switched by the switch
The forklift is provided with a notifying means for notifying that it is within the range of the optimum distance .

[0008]

According to the invention, there is provided a notifying means for notifying that the distance between the detector and the pallet is within the range of the optimum distance obtained from the length of the fork and the depth of the pallet,
In addition, a plurality of circuits preset in the range of the optimum distance
Select switch to select distance information from detector
By supplying, when the operator operates the forklift to scoop the pallet, when the distance between the detector and the pallet is optimized, the notifying means of the forklift informs the operator that scooping is possible, By operating the fork in accordance with the notification, the operator can easily prevent the danger that the fork enters the pallet too much and the rear pallet is picked up at the same time and the rear pallet is knocked down.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a partially cutaway perspective view showing a state in which a pallet is scooped by a forklift according to the present invention, FIG. 2 is a partially horizontal sectional view seen from above, and FIG. 3 is a sequence circuit diagram for controlling a notification means. . In these figures, the same members as those shown in FIG. 4 are the same members or equivalent members, and thus detailed description thereof will be omitted.

In these figures, reference numeral 4 denotes a distance detecting means, for example, an ultrasonic sensor. The ultrasonic sensor 4 is mounted on the fork mounting portion 20 by a mounting bracket 40 so that the ultrasonic wave hits the horizontal frame 30 a of the pallet 30 placed on the forks 21 and 22 and bounces off the ultrasonic sensor 4. Is configured.

A control unit 5 is connected to the ultrasonic sensor 4 by an electric signal cable 6. The control unit 5 is connected to the horizontal frame 30 a of the pallet 30 and the ultrasonic sensor in accordance with an electric signal sent from the ultrasonic sensor 4. 4
The distance between the pallet 3 and the length of the forks 21 and 22
It is configured to determine whether or not it is within the range of the optimum distance obtained from the depth of 0, and when it is within the range of the optimum distance, inform the operator that scooping is possible.

FIG. 2 particularly shows how the distance between the ultrasonic sensor 4 and the frame 30a is monitored. In the figure, L indicates the fork ends 21b and 22b.
From the tip to the tip 21a, 22a, P is the pallet 30
And d indicates the distance from the fork ends 21b and 22b to the measurement position of the ultrasonic sensor 4. Therefore, the distance between the ultrasonic sensor 4 and the frame 30a indicated by Q is obtained by adding the distance L from the fork ends 21b and 22b to the measurement position of the ultrasonic sensor 4 to the length L of the forks 21 and 22. When the distance is equal to the depth of the pallet 30 minus the fork tip 21
a and 22a have just been inserted into the pallet 30 by a depth that is just right for scooping.

Fork 2 used in the above calculation
Since the length L of the pallet 30 and the length L of the pallet 30 are always constant, the length L of the pallet 30 is constant. Therefore, when the depth of the pallet to be used changes to some predetermined size, the optimum distance for each of them can be set in advance.

For example, the depth P of each pallet is 900 m
m, 1000 mm, and 1100 mm, assuming that the length L of the forks 21 and 22 is 1200 mm and the distance d from the fork ends 21 b and 22 b to the measurement position of the ultrasonic sensor 4 is 10 mm. When the distance Q measured by the ultrasonic sensor 4 is 310 mm, 210 mm, and 110 mm, respectively, when the depth of the pallet is 900 mm, 1000 mm, and 1100 mm, it can be obtained by the above calculation.

Further, by providing the optimum distance with a certain width, the operator can more easily work within the range of the optimum distance. In the above-described example, the depth of each pallet changes in units of 100 mm. For example, when a pallet having a depth of 900 mm is scooped, the optimum distance is 310 mm. In this case, for example, 50 mm, that is, the range in which the measurement distance of the ultrasonic sensor 4 is 260 mm can be set within the range of the optimum distance.

Therefore, the worker can continue working within the optimum distance without having to use excessively nervous positioning. Note that the range of the optimum distance is too large, and the setting of the optimum distance for each pallet should not be meaningless, or the fork tips 21a and 22a should not reach the pallet 31 at the back. Needless to say.

FIG. 3 shows a sequence circuit inside the control device 5. In this FIG.
To 72 are amplifier main circuits that determine a range of an optimum distance set in advance according to the depth of each of the three pallets;
75 is a relay which is turned on by any one of the amplifier main circuits 70 to 72, 76 is a timer which starts the operation by the relay 75 and shuts off the circuit C after 5 seconds, for example, 8
Reference numerals 0 and 81 denote a lamp and a buzzer which are turned on by the relay 75 and turned off by the timer 76.
Is configured. Reference numeral 9 denotes a select switch for selectively supplying an electric signal from the ultrasonic sensor 4 to any of the three amplifier main circuits 70 to 72.

Next, a method in which the control device 5 monitors the electric signal given from the ultrasonic sensor 4 and determines whether or not the electric signal is within the optimum distance will be described step by step. First, the ultrasonic sensor 4 always measures the distance from the pallet 30. The amplifier main circuits 70, 71, and 72 respectively have three large, medium, and small depths (1100 in the above example).
mm, 1000 mm, 900 mm) within the range of the optimal distance (60 mm to 110 mm, 1 in the above example).
(60 mm to 210 mm, 260 mm to 310 mm).

The select switch 9 selects the type of pallet to be conveyed by supplying an electric signal of the ultrasonic sensor 4 to any of the three amplifier main circuits 70, 71, 72. When the forks 21 and 22 are inserted into the pallet 30 in this state, when the distance between the ultrasonic sensor 4 and the pallet 30 matches the distance preset in the switched amplifier main circuit, the amplifier main circuit Outputs an output and turns on the relay 75.

When the relay 75 is turned on, the lamp 80 and the buzzer 81 are turned on to notify the worker that the distance is within the range of the optimum distance, and the timer 76 starts operating and counts for 5 seconds. The circuit C for driving the lamp 80 and the buzzer 81 is shut off. Therefore, the lamp 80 and the buzzer 81 operate for 5 seconds after the worker adjusts to the range of the optimum distance, and informs the worker that the entering amount of the forks 21 and 22 at that time is optimum. The lamp 80 and the buzzer 81 stop.

Therefore, it is easy for the operator to work with the optimal amount of the forks 21 and 22 by the ramp 80 or the buzzer 81, and the fork tips 21a and 21
There will be no mistakes such as scooping up the frame 31a of the pallet 31 at the back due to excessive entry of 2a, or not reaching the frame 30b of the pallet 30 too deeply.
It is extremely safe, can effectively prevent occurrence of accidents and the like, and can perform work easily and quickly.

In the above embodiment, three amplifier main circuits 70, 71 and 72 are prepared so as to be able to cope with the depths of the three types of pallets. However, the present invention is not limited to this. More amplifier main circuits may be used. Further, in this embodiment, the pallet is selected by the select switch 9, but the volume adjustment for the distance setting of the amplifier main circuit may be directly performed.

Further, the detector for detecting the distance is not limited to the ultrasonic sensor 4 and the mounting method is also limited to the method for mounting the sensor to the fork mounting portion 20 via the mounting bracket 40 as in the above embodiment. I can't. Further, the notification means 8 is not limited to the lamp 80 or the buzzer 81.

[0024]

As described above, the forklift according to the present invention has a notifying means for notifying that the distance between the detector and the pallet is within the range of the optimum distance obtained from the length of the fork and the depth of the pallet. provided Rutotomoni, the pre
Select multiple circuits within the optimal distance range
Switch selectively supplies distance information from the detector
When the operator operates the forklift to pick up the pallet, the notification means of the forklift notifies the operator that the picking up is possible when the distance between the detector and the pallet becomes optimal. For,
The operator can easily recognize by this notification that the fork is at the optimum depth, so that the fork can be operated accurately in the optimum condition, the fork enters the pallet too much, and the back pallet simultaneously scoops up. It is very easy to prevent the rear pallet from being knocked down, or, on the other hand, the fork from entering the pallet too shallowly so that the front pallet is knocked down.

[Brief description of the drawings]

FIG. 1 is a partially broken perspective view showing a state where a forklift according to the present invention scoops up a pallet.

FIG. 2 is a partial horizontal sectional view of the forklift.

FIG. 3 is a sequence circuit diagram for controlling a notification means of the forklift.

FIG. 4 is a partial longitudinal sectional view showing a state where a conventional forklift lifts a pallet.

[Explanation of symbols]

1 ... forklift, 4 ... detector, 8 ... reporting means, 20 ...
Fork mounting part, 21,22 ... fork, 30 ... pallet,
L: fork length, P: pallet depth, Q: distance between detector and pallet.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 58-95998 (JP, U) Japanese Utility Model Sho 62-65499 (JP, U) Japanese Utility Model Hei 1-140400 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) B66F 9/24

Claims (1)

(57) [Claims] The method according to claim 1 detector to check the distance between the pallet fork attachment portion of the forklift is provided from the detector and <br/> numerical value by subtracting the depth distance from the length of the fork of the pallet with the pallet Set in advance within the range of the obtained optimal distance.
A plurality of circuits, and the detector
Switch to selectively supply the detection signal
A circuit in which the distance from the pallet detected by the detector is switched by the switch.
A forklift provided with a notifying unit for notifying that the distance is within the range of the preset optimum distance .