JP3942023B2 - Safety equipment for cargo handling vehicles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a safety device for preventing a cargo handling vehicle such as a forklift from falling from a platform or crashing into an obstacle while driving.
[0002]
[Prior art]
In general, forklifts are actively used to load and unload luggage on trucks. In this case, a so-called platform may be provided in which the road surface on which the forklift travels is raised one step higher than the road surface on which the truck travels in accordance with the height of the truck bed so that the cargo handling operation can be easily performed. The truck is stopped on the lower road surface of the platform, while the forklift is operated on the upper road surface of the platform to perform the cargo handling work. In such a cargo handling operation, the forklift is frequently switched between forward travel and reverse travel.
[0003]
By the way, when steering a forklift near the platform step as described above to load and unload a load, the driver must always pay attention to the road surface condition so that the wheel does not come off at the platform step. Is required.
[0004]
In particular, when the forklift is moved backward, the state of the load placed on the fork is distracted, the attention to the road surface condition in the reverse direction is distracted, and the presence of the stepped portion of the platform is not noticed. In this case, there is a risk that the forklift falls.
[0005]
In order to prevent the occurrence of such a problem, a guide wire is laid near the stepped portion of the platform, and an alarm is issued when this is detected by a pickup coil provided on the vehicle body. (See Patent Document 1). In addition, the distance to the road surface is detected by a distance measuring sensor provided on the body of the forklift, and when the detected distance becomes longer, it is determined that the forklift has approached the stepped portion of the platform and an alarm is generated or A device that is stopped is also proposed (see Patent Document 2).
[0006]
[Patent Document 1]
A microfilm of Japanese Patent Application No. 60-116886 (Japanese Utility Model Publication No. 62-23295) [Patent Document 2]
Japanese Patent Laid-Open No. 9-272700
[Problems to be solved by the invention]
However, it is not sufficient to ensure safety only by issuing an alarm, and there is a problem that if the vehicle suddenly stops during traveling, cargo collapse or the like occurs and hinders smooth cargo handling work.
[0008]
The present invention has been made to solve the above problems, and an object of the present invention is to provide a safety device capable of ensuring safety while performing a cargo handling operation smoothly.
[0009]
[Means for Solving the Problems]
In the first invention, the detected object is installed in the vicinity of the dangerous place on the traveling road surface of the cargo handling vehicle, and two detection means for detecting the detected object are provided before and after the vehicle, and When the first detection means provided at the rear of the vehicle detects the detected object, control is performed to issue an alarm, and when the second detection means provided at the front of the vehicle detects the detected object A controller that performs control for stopping the vehicle is provided. According to the first aspect of the invention, when the vehicle approaches the dangerous place, an alarm is first issued to alert the driver, and the vehicle can be stopped when the vehicle further approaches the dangerous place. Therefore, since the driver only needs to drive away from the dangerous place after the alarm is issued until the vehicle stops, danger can be avoided and smooth driving can be realized. In addition, since the driver is alerted in advance by an alarm, it is possible to avoid a shock or a collapse of the load due to an unexpected sudden stop of the vehicle. The detected object and each detection means can be configured as means for mediating electricity, magnetism, light, or the like. Moreover, the said to-be-detected body can arrange | position these in the shape of a line in the range which can be designed, or several dots. The controller is preferably installed in the cargo handling vehicle as a microcomputer.
[0010]
In the first aspect of the invention, the controller may issue an alarm that is issued when the vehicle is in a reverse drive state and the first detection means detects the detected object. It is characterized in that the control is carried out so as to release when the means detects the detected object again. Therefore, the alarm is continuously issued while the vehicle is in a position close to the dangerous place, which is useful for prompting the driver to leave the dangerous place.
[0011]
According to a second aspect, in the first aspect, the controller stops the vehicle when the second detection means detects the detected object, and then prohibits the vehicle from moving backward and allows the vehicle to move forward. It is characterized by performing control for this purpose. According to the second aspect of the invention, after the vehicle is forcibly stopped by the controller, access to the dangerous place is prohibited, but driving in a direction away from the dangerous place is permitted. You can avoid danger.
[0012]
A third invention is characterized in that, in the invention according to the first or second aspect , the detected body is laid or buried on the traveling road surface so that the vehicle can travel on the detected body. Yes. According to the third aspect of the invention , the detected object itself does not become an obstacle, and there is an advantage that safe driving can be ensured while ensuring smooth running of the vehicle. The object to be detected may be formed by adhering an adhesive magnetic tape on a road surface or by embedding a magnetic rod, and these may be detected by a magnetic sensor as the detection means. The object to be detected may be a wire or the like that emits current or emits radio waves, and may be electrically detected by the detection means.
[0013]
According to a fourth invention, in the inventions according to the first to third aspects , the detected object has a distance greater than a horizontal distance between the second detection means and the center of the rear wheel of the vehicle from the dangerous place. It is characterized by being installed. According to the fourth aspect of the present invention , since the rear wheel of the vehicle does not reach the dangerous place when the vehicle stops, the danger of the vehicle body falling can be avoided when the dangerous place is a stepped portion of the platform. It is effective.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0015]
FIG. 1 is an explanatory diagram showing the overall configuration of a safety device according to an embodiment of the present invention. In this embodiment, an example of a forklift is used as a cargo handling vehicle, and an apparatus for preventing the forklift from falling from a stepped portion of the platform is disclosed.
[0016]
In this embodiment, a guide wire 5 as an object to be detected is embedded in the upper road surface 3 in the vicinity of the stepped portion 2 of the platform, which is a dangerous traveling place of the forklift 1. That is, the guide wire 5 is made of a magnetic material such as iron, so that the rear wheel 7 of the forklift 1 is not removed from the upper road surface 3 when a second sensor 22 described later detects the guide wire 5. It is embedded along the stepped portion 2 of the platform and at a position away from the stepped portion 2 by a certain distance L1. That is, the distance L1 is set to be larger than the horizontal distance L2 between the second sensor 22 and the center of the vehicle rear wheel 7 in the side view shown in FIG. The distance is set such that the rear wheel 7 is not removed from the upper road surface 3 when 5 is detected and the vehicle body is suddenly stopped.
[0017]
On the other hand, the forklift 1 in this embodiment is of a so-called counterbalance type, and a mast 9 for guiding the lifting and lowering operation of the fork 8 on which the load W is placed is disposed at the front of the vehicle body 6. A counterweight 10 is provided at the rear of the vehicle 6, and a driver's seat 11 on which the driver is boarded is secured at a substantially central portion of the vehicle body 6. Reference numeral 14 denotes a handle and 15 denotes a head guard.
[0018]
Further, the vehicle body 6 of the forklift 1 is provided with detection means 20 for detecting the guide wire 5 described above. The detection means 20 includes a first sensor 21 as a first detection means provided on the rear end side of the vehicle body 6 and a second sensor as a second detection means provided on the vehicle body front side with respect to the first sensor 21. 22. Both of these sensors 21 and 22 are electromagnetic induction-type sensors, and when each sensor 21 and 22 approaches the guide wire 5, the strength of the magnetic line of force between them changes, so that the presence of the guide wire 5 exists. Can be detected.
[0019]
FIG. 2 is a block diagram showing a schematic configuration of an operation control system provided in the forklift 1. In FIG. 2, 24 is a forward / reverse switching lever that switches between a mode in which the vehicle body 6 travels forward and a mode in which the vehicle travels backward, and 25 is an accelerator lever for speed adjustment. Reference numeral 26 denotes a traveling mechanism unit having a traveling motor or the like that causes the vehicle body 6 to travel in a forward direction or a backward direction at a predetermined speed according to the operation of the forward / reverse switching lever 24 and the accelerator lever 25, and 27 indicates that the forklift 1 travels. For example, a buzzer, a lamp, a sound generator or the like is applied as an alarm device that issues an alarm when it is dangerous.
[0020]
Reference numeral 28 denotes a controller such as a microcomputer. The controller 28 operates the alarm device 27 when the detection output of the first sensor 21 is detected when the vehicle body 6 moves backward, decelerates the traveling by the traveling mechanism unit 26, and If the detection output of the second sensor 22 is present when the vehicle body 6 is moving backward, control is performed to forcibly stop the traveling operation by the traveling mechanism section 26. In the present embodiment, the controller 28 is set so as to perform the above-described controls such as alarm, deceleration, stop, etc., when the sensors 21 and 22 approach almost directly above the guide wire 5. Although not shown, the operation control system shown in FIG. 2 includes an elevating lever and an elevating mechanism for operating the fork 8 up and down.
[0021]
Next, the control operation of the forklift in the above configuration will be described with reference to the flowchart shown in FIG. In addition, the code | symbol S means each step.
[0022]
First, the controller 28 determines whether or not there is a detection output from the first sensor 21 to the guide wire 5 (S1). If there is a detection output, is the reverse travel mode set by the forward / reverse switching lever 24? It is determined whether or not (S2). When there is no detection output or when the forward running mode is set, it is determined that the vehicle body 6 is not likely to fall from the stepped portion 2 of the platform, and the process returns to step S1 again.
[0023]
Here, when there is a detection output from the first sensor 21 and the vehicle body is in the reverse drive state, the controller 28 determines that the vehicle body 6 is in a dangerous state approaching the stepped portion 2 of the platform and issues an alarm device. 27 is activated to issue a warning by a buzzer, a lamp, a voice, etc., and the operation amount of the accelerator lever 25 is ignored, and the traveling mechanism unit 26 is controlled to decelerate the vehicle to travel at a low speed (S3).
[0024]
After that, if there is a detection output from the first sensor 21 again (S4), the vehicle body 6 is switched to the forward mode and moved forward to move forward from the position of the first sensor 21 and away from the stepped portion 2 of the platform. to decide. Then, the operation of the alarm device 27 is stopped, the deceleration control is released, and the traveling mechanism unit 26 is controlled so that the traveling speed according to the operation amount of the accelerator lever 25 is reached (S5). If there is no detection output from the first sensor 21, the controller 28 determines whether there is a detection output from the second sensor 22 to the guide wire 5. If there is no detection output from the second sensor 22, the process returns to step S4 (S7).
[0025]
When the detection output of the second sensor 22 is received after step S4, the controller 28 determines that the vehicle body is extremely close to the stepped portion 2 of the platform while maintaining the reverse movement state, and controls the traveling mechanism 26. The traveling operation is forcibly stopped (S7).
[0026]
Next, the controller 28 determines whether or not the forward / reverse switching lever 24 has switched to the forward travel mode (S8). When the forward travel mode is entered, or when the accelerator is depressed in the forward travel mode, the travel mechanism unit 26 is controlled to cancel the travel stop state (S9), and then the process returns to step 5.
[0027]
Thus, in the safety device in this embodiment, when the vehicle body 6 of the forklift 1 approaches the stepped portion 2 of the platform, the first sensor 21 provided on the vehicle body 6 detects the guide wire 5 and issues an alarm. At the same time, the vehicle body is decelerated, and then the vehicle body is stopped when the second sensor 22 detects the guide wire 5. Therefore, the risk of the vehicle body falling from the platform is surely avoided, and since the vehicle body does not suddenly stop without any notice, the cargo handling operation can be performed smoothly.
[0028]
In this embodiment, the dangerous travel location of the forklift 1 has been described as the stepped portion 2 of the platform. For example, an obstacle such as a wall of a building or a curb is at risk of colliding when the vehicle body 6 travels. It is also possible to lay or embed the detected object 2 in advance on the road surface in the vicinity of a dangerous place.
[0029]
In the above embodiment, the case where the present invention is applied to a counterbalance type forklift has been described. However, the present invention is not limited to this, and other types of forklifts such as a reach type and an opicking type, or other types. It can be widely applied to various cargo handling vehicles. In addition, it is not limited to the structure of this invention, and it cannot be overemphasized that it can change suitably and implement in the range which does not deviate from the meaning of this invention.
[0030]
【The invention's effect】
According to the safety device of the present invention, the following effects can be obtained.
[0031]
In the invention according to claim 1, there is an effect that the risk of the vehicle body falling from the platform is avoided and the cargo handling operation can be performed smoothly.
[0032]
In the invention according to claim 1, since the alarm is continuously issued while the vehicle is in a position close to the dangerous place, there is an effect of prompting the driver to leave the dangerous place.
[0033]
In the invention according to claim 2, in addition to the effect of the invention according to claim 1 , after the vehicle is forcibly stopped by the controller, access to the dangerous place is prohibited, but the vehicle is moved away from the dangerous place. Since driving in the direction is allowed, there is an effect of reliably avoiding danger.
[0034]
In the invention according to claim 3, in addition to the effect of the invention according to claim 1 or 2 , the detected body itself does not become an obstacle, and safe driving is ensured while ensuring smooth running of the vehicle. There is an effect that can be done.
[0035]
In the invention according to claim 4, in addition to the effects of the inventions according to claims 1 to 3 , the rear wheel of the vehicle does not reach the dangerous place when the vehicle stops. When it is a stepped portion, there is an effect that the danger of the vehicle body falling can be avoided.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an overall configuration of a safety device according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a schematic configuration of an operation control system provided in the forklift in the embodiment of the present invention.
FIG. 3 is a flowchart for explaining a road surface monitoring process operation in the safety device according to the embodiment of the present invention.
[Explanation of symbols]
1 Forklift (handling vehicle)
2 Stepped part of the platform (hazardous location)
5 Guide wire (object to be detected)
20 detection means 21 first sensor (first detection means)
22 Second sensor (second detection means)
28 controller

Claims (4)

A detected object is installed in the vicinity of a dangerous place on the road surface of the cargo handling vehicle, and two detection means for detecting the detected object are provided before and after the vehicle, respectively, and provided at the rear of the vehicle. When the first detection means detects the detected object, control is performed to issue an alarm, and when the second detection means provided in front of the vehicle detects the detected object, the vehicle is stopped. There is provided a controller for performing control , and the controller issues an alarm that is issued when the vehicle is in a reverse drive state and the first detection means detects the detected object, and the vehicle is in a forward drive state and the first A safety device for a cargo handling vehicle that performs control so as to be released when one detecting means detects the detected object again . The controller, after the second detecting means of the vehicle is stopped upon detecting the detection object, in claim 1, characterized in that for performing control to permit advancement prohibits backward of the vehicle Safety equipment for cargo handling vehicles as described. The cargo handling vehicle according to claim 1 , wherein the detected object is laid or embedded in the traveling road surface so that the vehicle can travel on the detected object. Safety equipment. 4. The detection object according to claim 1, wherein the detected object is installed at a distance greater than a horizontal distance between the second detection means and a rear wheel center of the vehicle from the dangerous place . The safety device for a cargo handling vehicle according to any one of the above.

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