JP2002087794A - Cargo handling safety device for industrial vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out smooth and rapid cargo handling work by detecting the abnormal insertion direction of a fork to a pallet when the fork is moved for insertion into an opening part of the pallet and by informing an operator of the abnormal state. SOLUTION: When the fork 4 having a photoelectric sensor 4a mounted on its side face is moved for insertion into the opening part 6a of the pallet 6, and when the photoelectric sensor 4a receives and detects the reflected light from the pallet 6, a lamp is lit by the detection signal so that the abnormal state is reported to the operator. The operator keeps the parallelism of the insertional movement direction of the fork 4 to the opening part of the pallet 6 by tilting a mast. Thus, the thrusting up or the like of the pallet 6 by the tip of the fork 4 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cargo handling safety device for an industrial vehicle, and more particularly to a technique for smoothly inserting a fork of an industrial vehicle into a pallet.

[0002]

2. Description of the Related Art Conventionally, an industrial vehicle, in particular, a forklift for moving a fork up and down along a mast is placed on a high frontage of a rack having a plurality of frontages in a longitudinal direction and an upward direction disposed on a road surface. When unloading a pallet (assuming a load is placed on this pallet), an attempt is made to insert a fork into the opening of the pallet,
The operator adjusted the mast by tilting the mast back and forth so that the fork was raised and the fork was parallel to the opening of the pallet. Such adjustment work is a visual operation of the operator, and when unloading the pallet placed on the high frontage of the rack, it must be adjusted many times, and such adjustment work is cumbersome and skilled work. there were.

[0003] In order to relieve such troublesome and skilled work, a vertical gauge for detecting that the mast is perpendicular to the traveling road surface of the forklift is fixed to the mast, and the mast is attached to the traveling road surface by the vertical gauge. When the operator confirms that the pallet is vertical, the operator inserts a fork into the opening of the pallet placed on the high frontage of the rack and unloads the pallet.

[0004]

However, the operator confirms that the mast is perpendicular to the traveling road surface by the vertical gauge, and the operator inserts a fork into the opening of the pallet placed on the high frontage of the rack. Even if the fork is inserted, the parallelism with the fork travel road surface is not always maintained due to unevenness of the installation road surface due to the rack installation location and unevenness of the floor surface itself. The tip could push up the pallet, causing load collapse.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and detects that an insertion direction of a fork with respect to a pallet is abnormal when the fork is being inserted and moved into an opening of the pallet. An object of the present invention is to provide a cargo handling safety device for an industrial vehicle that can smoothly and quickly carry out cargo handling work by changing the fork insertion / moving direction. It is.

[0006]

In order to achieve the above object, an invention according to claim 1 is provided with a fork for transporting a load placed on a pallet by inserting the fork into an opening of the pallet. An industrial vehicle having a mast that locks a fork so as to be vertically movable and tilts in a front-rear direction.
A photoelectric sensor that detects an obstacle positioned in front of the fork mounted on the side of the fork, and operates by a detection signal when the photoelectric sensor detects the pallet during insertion movement of the fork into the opening of the pallet, A notification means for notifying the operator of the abnormality is provided.

In the above configuration, when the fork is inserted into the opening of the pallet and is moved, if the photoelectric sensor mounted on the side of the fork detects an obstacle, the detection signal is activated by the detection signal to notify the operator. Report anomalies. Therefore, when the operator maintains the degree of parallelism between the insertion movement direction of the fork and the opening of the pallet by tilting the mast, the operation of the notification means ends. Thus, the operation of inserting the fork into the pallet can be performed smoothly.

According to a second aspect of the present invention, in the cargo handling safety apparatus for an industrial vehicle according to the first aspect, the side surface of the fork is cut away from the tip end on the loading surface side toward the vehicle body, and the cutout portion is provided with the photoelectric member. The sensor is mounted so that its optical axis is directed toward the tip of the fork. In this configuration, it is possible to prevent the photoelectric sensor from being inadvertently brought into contact with the pallet or another object and damaged.

According to a third aspect of the present invention, in the cargo handling safety device for an industrial vehicle according to the first aspect, the photoelectric sensor has a structure in which an obstacle located at least near the tip of the fork is used as a detection area. In this configuration, unnecessary obstacle detection is not performed by narrowing the obstacle detection area.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cargo handling safety device for an industrial vehicle according to one embodiment of the present invention will be described below with reference to the drawings. 1 (a) and 1 (b) show a side configuration of a forklift and a rack on which a cargo operation is performed according to the present embodiment. The forklift 1 carries out the work of carrying out and carrying in the pallet 6 to and from the rack 9 laid on the traveling road surface. The forklift 1 is a so-called counter type, and includes a vehicle body 2, a mast 3 attached to the vehicle body 2 so as to be tiltable in front of the vehicle body 2, and a pair of the masts 3 movable in the left and right directions in the vertical direction. A fork 4, a front wheel 2 b connected to a traveling drive device (not shown) disposed below and forward of the vehicle body 2, a rear wheel 2 c disposed below and rearward of the vehicle body 2, and disposed on a side surface of the fork 4; A photoelectric sensor 4a for detecting an obstacle,
The fixed side mast 3a of the mast 3 includes a lamp 5 (notifying means) which operates according to a detection signal of the photoelectric sensor 4a and notifies an operator of abnormalities by lighting.

The mast 3 comprises a fixed mast 3a which is mounted to be tiltable in front of the vehicle body 2, and a movable mast 3b which moves vertically along the fixed mast 3a. The lift cylinder 3r is fixed to the fixed mast 3a with the rod side facing upward, and the movable mast 3b and the fork 4 are moved up and down by the telescopic movement of the rod. One end of the tilt cylinder 3t is fixed to the frame 2, and tilts the fixed mast 3a in the front-rear direction in accordance with the expansion and contraction of the rod.

The extension and retraction of the rod of the lift cylinder 3r and the extension and retraction of the rod of the tilt cylinder 3t are attached to the dashboard 2a fixed on the upper front of the frame 2 and the rear wheel 2
The operation is performed by a lift cylinder operation lever 23r and a tilt operation lever 23t provided together with a steering handle 2s capable of changing the direction of the traveling direction of c.

The rack 9 is provided with a plurality of columns 9a standing upright in the width and depth directions perpendicular to the road surface.
A horizontal member 9b on which a load w is placed together with the pallet 6 is fixed in multiple stages in the vertical direction.

Next, the pallet 6 will be described in detail with reference to FIG. The pallet 6 has a plurality of deck boards 6a each having a fixed length, width and thickness, and a plurality of deck boards 6a arranged at predetermined intervals in the length direction of the pallet 6 and arranged in the length direction of the pallet 6 to form an upper surface 6b. An opening 6s through which the fork 4 of the forklift 1 can be inserted is formed between the upper deck board 6a and the lower deck board 6a.

FIG. 3 shows the structure of the fork 4. In the fork 4, a photoelectric sensor 4a is provided with an optical axis 4h at a notched portion 4b closer to the vehicle body side from the loading surface side tip of the fork 4.
Is mounted facing the tip side of the fork 4. In addition,
The detection area of the photoelectric sensor 4a is set near the tip of the fork 4, and is set so as not to detect a distant place in order to prevent unnecessary malfunction.

FIG. 4 shows an operation state of the photoelectric sensor.
(A) shows a state where the photoelectric sensor is operating normally,
FIG. 4B illustrates a state in which the photoelectric sensor detects an obstacle, in this embodiment, a pallet. As shown in FIG. 4A, when the fork 4 is inserted and moved (in the direction of arrow A) in a state parallel to the lower surface or the upper surface of the deck board 6a of the pallet 6, the photoelectric sensor 4a does not detect an obstacle. Work can be continued.

When the pallet 6 is placed on the rack 9 at an angle, for example, as shown in FIG. 4B, the fork 4 is held at an angle with the lower surface of the deck board 6a. When inserted and moved, the photoelectric sensor 4a receives the reflected light from the deck board 6a of the pallet 6, and determines that there is an obstacle, and the photoelectric sensor 4a operates to turn on the lamp 5. When the lamp 5 is turned on, the operator operates the tilt operation lever 23t to tilt the mast 3 forward until the lamp 5 is turned off, whereby the fork 4 tilts in a direction to lower the tip of the fork 4. As a result, FIG.
As shown in (a), the fork 4 is parallel to the lower surface or the upper surface of the deck board 6a, the photoelectric sensor 4a stops receiving the reflected light, and the lamp 5 is turned off. The operator confirms that the lamp 5 is turned off, and as usual, forks 4
Can be inserted into the pallet.

FIG. 5 shows a lighting control circuit 8 for the lamp 5 controlled by the photoelectric sensor 4a. This control circuit 8
A photoelectric sensor 4a, a switching element 8a connected to the base side of the photoelectric sensor 4a,
and a relay contact 8c which is operated by the exciting coil 8b which is connected to the collector side of the lamp lighting relay 8a and which is energized by the switching element 8a being turned on and energized.
And the lamp 5 connected in series to the relay contact 8c. When the photoelectric sensor 4a provided on the fork 4 receives reflected light from the inner surface of the deck board 6a serving as an obstacle during the insertion movement of the fork 4 on the pallet 6, the photoelectric sensor 4a conducts the switching element 8a, and When the excitation coil 8b is energized, the relay contact 8c is closed and the lamp 5 is turned on.

When the operator senses an abnormal state by turning on the lamp 5, the mast 3 is tilted forward by operating the tilt operation lever 23t, and the photoelectric sensor 4a does not receive the reflected light from the pallet 6; 8a becomes non-conductive, the relay contact 8c opens, and the lamp 5 is turned off. The operator confirms that the lamp 5 is turned off, and stops the forward tilting operation of the mast 3. At the position where the forward tilting operation of the mast 3 is stopped, the fork 4 can be inserted into the opening 6s of the pallet 6 without any obstacle.

According to the cargo handling safety device of the forklift of the present embodiment, when the fork 4 is inserted and moved into the opening 6s of the pallet 6, the photoelectric sensor 4a mounted on the side of the fork 4 reflects from the pallet 6. Light is detected, and until the lamp 5 turned on by the detection signal is turned off,
When the operator moves the mast 3 forward,
Insertion movement of fork 4 and deck board 6a of pallet 6
It is possible to easily adjust the degree of parallelism between the lower surface and the upper surface.

The present invention can be variously modified without being limited to the configuration of the above embodiment. For example, as shown in FIG. 6, when unloading the pallet 6 placed near the wall H, the fork 4 is inserted and moved in parallel with the opening 6s of the pallet 6, and the wall H positioned near the tip of the fork 4 is moved. Is detected, the lamp 5 is turned on, and the operator confirms this and stops the movement of the fork 4 inserted into the opening 6s of the pallet 6 so that the fork 4 and the wall H are stopped.
Can be avoided.

Further, the operator confirms that the lamp 5 is lit, and does not stop the movement of the fork 4 by manual operation, but automatically stops the movement of the fork 4 simultaneously with the detection of the photoelectric sensor 4a. If the operation until the light is turned off is manually performed, the safety is enhanced.

[0023]

As described above, according to the cargo handling safety device for an industrial vehicle of the present invention, the photoelectric sensor mounted on the side of the fork detects the pallet during the insertion and movement of the fork into the opening of the pallet. At this time, since the notifying means for notifying the abnormality is activated, the operator can quickly recognize the abnormality and adjust immediately so as to maintain the parallelism between the insertion movement of the fork and the opening of the pallet. It is possible to smoothly and quickly insert the fork into the pallet.

In addition, a photoelectric sensor is mounted on a notched portion of the side surface of the fork so that its optical axis is directed toward the tip of the fork, so that the photoelectric sensor can be brought into contact with a pallet or another object. It can be avoided from damage.

Further, by employing a structure in which the photoelectric sensor uses an obstacle located near the tip of the fork as a detection area, unnecessary detection is prevented, and as a result, the detection capability is improved and malfunctions can be reduced. Become.

[Brief description of the drawings]

FIG. 1A is a side view of a forklift according to an embodiment of the present invention, and FIG. 1B is a side view of a rack that is loaded and unloaded by the forklift.

FIG. 2 is a perspective view of a pallet used in the embodiment.

FIG. 3 is a perspective view of a fork used in the embodiment.

FIG. 4A is a side view when the fork insertion state is normal, and FIG. 4B is a side view when the fork insertion state is abnormal.

FIG. 5 is a configuration diagram of a lamp lighting control circuit.

FIG. 6 is a side view of another use mode of the forklift.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Forklift (industrial vehicle) 3 Mast 4 Fork 4a Photoelectric sensor 5 Lamp (notification means) 6 Pallet 6s Opening

Claims (3)

[Claims] 1. A fork for transporting a load placed on a pallet by being inserted into an opening of a pallet, and a mast that locks the fork so as to be vertically movable and tilts in the front-rear direction. In the industrial vehicle, a photoelectric sensor that detects an obstacle located in front of the fork mounted on the side surface of the fork, and when the photoelectric sensor detects the pallet during the insertion movement of the fork into the opening of the pallet, A cargo handling safety device for an industrial vehicle, comprising: a notifying unit that operates according to the detection signal and notifies an operator of an abnormality. 2. A side surface of the fork is cut away from a tip end on a loading surface side toward a vehicle body, and the photoelectric sensor is mounted in the notched portion with its optical axis directed toward the tip end of the fork. The cargo handling safety device for an industrial vehicle according to claim 1, wherein: 3. The cargo handling and safety device for an industrial vehicle according to claim 1, wherein the photoelectric sensor sets an obstacle located at least near a tip of the fork as a detection area.