JP4080342B2 - Warning device for lifting platform - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a load receiving device lifting device provided at the rear or side of a load carrier of a freight vehicle such as a van type truck, and more particularly to a warning device that warns of this situation when the load receiving device is tilted during lifting. .
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a large number of load receiving platform lifting devices are provided in which, for example, a load receiving platform is provided at a rear end portion of a cargo vehicle so as to be movable up and down via a link mechanism.
[0003]
The load receiving platform elevating device is movable up and down between a most elevated position substantially flush with the load platform and a most lowered position where the load receiving platform contacts the ground, and at the lowest position where the load receiving platform contacts the ground when lowered. When it reaches, it shifts to a tilting action and the tip of the load receiving platform is grounded to the ground. Further, the load receiving platform is rotated to the loading platform side at the highest position so as to be stowed for storage and running (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-233114
[Problems to be solved by the invention]
By the way, in the above conventional load receiving device lifting device, the load receiving device is normally moved up and down while maintaining a horizontal state. When a load is applied, the tip of the load receiving table may be inclined downward.
[0006]
Thus, when the load receiving platform is tilted unexpectedly during the up-and-down operation, there is a problem that the load is inadvertently moved on the load receiving table or falls and is dangerous.
[0007]
The present invention has been made in view of the above-described problems, and the object of the present invention is to warn the operator of this situation when the load receiving platform is tilted during the lifting and lowering operation, and so on. It is an object of the present invention to provide a warning device for a load receiving platform lifting / lowering device capable of preventing accidents in advance and performing highly safe work.
[0008]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a warning device for the load receiving platform lifting apparatus, wherein the load receiving platform is provided between the ground and a load platform positioned at a predetermined height from the ground so as to be movable up and down via a link mechanism. In a load receiving platform lifting device that is tilted so that its tip is grounded on the ground, when the tip tilts downward during the lifting operation of the load receiving platform, this is detected. A detector is provided, and an alarm means is activated based on the detection of the detector.
[0009]
According to a second aspect of the present invention, there is provided a warning device for the load receiving platform lifting apparatus, wherein the link mechanism includes a tilt link for tilting the load receiving platform on the ground so that the front end thereof is grounded. The alarm means is activated by detecting the swinging motion of the link.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0011]
FIG. 1 to FIG. 4 show a schematic configuration of a load receiving table lifting device of the present invention provided in a freight vehicle.
[0012]
In FIG. 1, the load receiving platform lifting device X is attached to a rear portion of a vehicle body frame including a main frame of the cargo vehicle 1 via a support member 10. The load receiving table elevating device X includes a tilt link 2, a lift arm 3, a tilt cylinder 4, a lift cylinder 5 (only one of which is shown) and a load receiving stand 6, which are arranged on the left and right, respectively.
[0013]
The support member 10 includes a frame member 11 extending in the vehicle width direction below the rear end portion of the vehicle body frame, a pair of left and right fixed brackets 12 for fixing the frame member 11 to the rear end portion of the vehicle body frame, and the frame. Support brackets 13 provided at both the left and right positions of the material 11 are provided. Each of the support brackets 13 has opposing pieces 13a that face each other in the vehicle width direction.
[0014]
A loading platform 15 is mounted on the vehicle body frame.
[0015]
Each tilt link 2 is formed in a substantially U-shaped cross section that opens to the rear of the vehicle body frame and extends in the vertical direction. The upper end (base end) of the tilt link 2 is located above the opposing piece 13 a of the support bracket 13 via a pin 21. The lower end side (front end side) is pivotably connected so as to swing in the contact / separation direction with respect to the support member 10, that is, the longitudinal direction of the vehicle body. In this case, each tilt link 2 has a storage position (position shown in FIG. 1) in which the lower end side is stored in contact with the frame member 11 in the opposed piece 13a of the support bracket 13, and from the opposed piece 13a to the rear of the vehicle body. They are mutually converted into a separation position (position shown in FIG. 3) for separation.
[0016]
Each lift arm 3 extends in the longitudinal direction of the vehicle body, and its front end (base end) is rotatably connected to the upper end portion of the tilt link 2 via a pin 31. The rear ends (tips) of the lift arms 3 are rotatably connected to both the left and right positions of the upper end portion of the load receiving platform 6 via pins 32, respectively.
[0017]
Each tilt cylinder 4 is composed of a hydraulic cylinder, and is disposed below the lift arm 3 so as to extend in the longitudinal direction of the vehicle body. The front end of each tilt cylinder 4 is rotatably connected via a pin 41 between an opposing piece 13a on the outside of the support bracket 13 and a bracket piece 16 facing the opposing piece 13a from the outside. Yes. On the other hand, the rear end of each tilt cylinder 4 is rotatably connected to the left and right end positions of the lower end portion of the load receiving platform 6 via pins 42. In this case, each tilt cylinder 4 is laid out below the lift arm 3 diagonally outward.
[0018]
Each lift cylinder 5 is composed of a hydraulic cylinder, and is arranged extending below the lift arm 3 in the longitudinal direction of the vehicle body. The front end of each lift cylinder 5 is rotatably connected to the lower end of the tilt link 2 via a pin 51. The rear ends of the lift cylinders 5 are rotatably connected to the front end side of the substantially intermediate portion of the lift arm 3 via pins 52, respectively.
[0019]
The load receiving platform 6 is moved upward by moving each lift cylinder 5 to be positioned at the highest position (the position shown in FIG. 1) that is substantially flush with the load loading platform 15, while each lift cylinder 5 is contracted. It is positioned at the lowest descending position (position shown in FIG. 2) that descends by moving and contacts the ground (ground) G.
[0020]
The load receiving platform 6 has a substantially triangular cross section when viewed from the side of the vehicle body, and a lifting operation state (the state shown in FIGS. 1 and 2) in which the mounting surface 61 (upper surface) is horizontal, and the rear end of the mounting surface 61 They are mutually converted into a downward tilt (tilting) state (the state shown in FIG. 3) in which the (tip) contacts the ground G.
[0021]
And by the continuous standing operation by the operation switch, the load receiving platform 6 covers the mounting surface 61 so as to cover the rear opening of the loading platform 15 from the rear from the lying state where the mounting surface 61 is horizontal at the highest position. It can be converted into an upright state (the state shown in FIG. 4). On the other hand, the load receiving platform 6 can be converted from the standing state to the lying state at the highest position by continuous lying operation with the operation switch.
[0022]
Next, the tilt operation and the undulation operation associated with the lifting operation of the load receiving platform 6 by the above-described load receiving platform lifting device X will be described. In this case, it is assumed that the cargo receiving platform 6 is positioned at the highest position (the position shown in FIG. 1).
[0023]
First, when the unloading switch (not shown) is turned on to lower the load receiving platform 6, the pressure oil in the non-rod side chamber (not shown) of each lift cylinder 5 is gradually increased by the action of a load such as its own weight of the load receiving platform 6. Each lift cylinder 5 starts to contract, and each lift cylinder 5 and each lift arm around the front end pin 51 of each lift cylinder 5, the front end pin 31 of each lift arm 3, and the front end pin 41 of each tilt cylinder 4 3 and each tilt cylinder 4 are rotated downward.
[0024]
Thereby, the load receiving platform 6 is lowered by the rotation around the pin 52 at the rear end of each lift cylinder 5 and the pin 32 at the rear end of each lift arm 3 while being held in a horizontal state. At this time, each tilt link 2 is directed to the disengagement position (the position shown in FIG. 3) at the rear of the vehicle body because the load receiving table load is applied to each lift cylinder 5 when the load receiving table 6 is moved up and down. The force is not applied and is held in the retracted position (position shown in FIG. 1).
[0025]
After that, when the load receiving platform 6 is positioned at the lowest lowered position (position shown in FIG. 2) where it contacts the ground G, each tilt link 2 swings backward to the vehicle body to the disengagement position (position shown in FIG. 3). With the pin 42 at the rear end of the tilt cylinder 4 as a fulcrum, the rear end of the load receiving platform 6 (mounting surface 61) tilts downward and is automatically converted into a tilted state (the state shown in FIG. 3).
[0026]
In this case, the conversion of the load receiving platform 6 into the tilted state is such that a downward load acts on the rear end of the load receiving platform 6 when the front end of the lower surface of the load receiving platform 6 that descends while maintaining the horizontal state first contacts the ground G. Is done by doing. That is, the tilt cylinders 2 are tilted by moving the pins 32 at the rear ends of the lift arms 3 to the rear of the vehicle body while further contracting the lift cylinders 5 from the ground contact position of the load cradle 6 by the load at the ground contact position of the load cradle 6. This is because the rear end of the load receiving platform 6 tilts downward with the pin 42 at the rear end of the tilt cylinder 4 as a fulcrum.
[0027]
In this way, when the load receiving platform 6 is lowered to the grounding position where it contacts the ground G, each tilt link 2 automatically swings to the rear side of the vehicle body due to the rotational moment related to the pin 42 of the load receiving platform 6. As each tilt link 2 swings, the pin 32 at the rear end of the lift arm 3 similarly moves to the rear of the vehicle body, and the rear end of the load receiving platform 6 is automatically lowered downward with the pin 42 at the rear end of the tilt cylinder 4 as a fulcrum. It is possible to tilt and load / unload the cargo smoothly.
[0028]
On the other hand, when lifting the unloading switch (not shown) to raise the load receiving platform 6 in the tilted state from the grounding position, pressure oil is supplied into the anti-rod side chambers (not shown) of the lift cylinders 5 and the lifts are lifted. The cylinder 5 begins to extend, the rear end of the load receiving platform 6 tilts upward with the pin 42 at the rear end of the tilt cylinder 4 as a fulcrum, and is converted into a horizontal state, whereby the load receiving platform 6 is moved to the lowest lowered position (load receiving platform). 6 in a state in which only the front end of the lower surface of the 6 contacts the ground G).
[0029]
The lift cylinders 5 are continuously extended as they are, so that the lift cylinders 5 around the front end pins 51 of the lift cylinders 5, the front end pins 31 of the lift arms 3 and the front end pins 41 of the tilt cylinders 4, Each lift arm 3 and each tilt cylinder 4 are rotated upward. As a result, the load receiving platform 6 rises by rotating around the pin 52 at the rear end of each lift cylinder 5 and the pin 32 at the rear end of each lift arm 3 while being held in a horizontal state, and is substantially flush with the load platform 15. It is positioned at the highest position.
[0030]
Further, when the stand is operated to raise the load receiving platform 6 at the highest position, pressure oil is supplied into the non-rod side chamber (not shown) of each tilt cylinder 4 and each tilt cylinder 4 starts to extend. Then, the rear end of the load receiving platform 6 rotates upward with the pin 32 at the rear end of the lift arm 3 as a fulcrum, and the load receiving platform 6 is converted from the lifting / lowering operation state (horizontal state) to the standing state (state shown in FIG. 4). . In this manner, the load receiving platform 6 is raised by rotating the tilt cylinders 4 at the highest position so as to rotate upward around the pin 32 at the rear end of the lift arm 3, so that the load receiving table 6 can be received at the highest position. The raising and lowering operation of the platform 6 can be easily performed by the extension movement of each tilt cylinder 4 and used as an opening / closing door that covers the rear opening of the cargo platform 15 of the cargo vehicle 1 from the rear by raising the cargo receiving platform 6. Can do.
[0031]
Further, in order to convert the load receiving platform 6 from the standing state to the raising / lowering operation state, when a tilting operation is performed, the pressure oil in the rod side chamber (not shown) of each tilt cylinder 4 is caused by the action of a load such as its own weight. Then, each tilt cylinder 4 is contracted and discharged, whereby the cargo receiving platform 6 is converted into an ascending / descending operation state by an operation reverse to that described above.
[0032]
By the way, the load receiving table lifting device X configured as described above is provided with a warning device 7 (see FIG. 5) for warning when the load receiving table 6 is tilted during lifting.
[0033]
As shown in FIG. 5, the warning device 7 includes a detector 71 that detects the swing of the tilt link 2 toward the separation position. The detector 71 is provided on the bottom of the frame material 11 via a bracket 11 a so as to face the lower end of the tilt link 2.
[0034]
As the detector 71, for example, a proximity switch is used. For example, when the tilt link 2 is disposed at the retracted position, the detector 71 is turned off. The circuit is configured to be turned on, and when the detector 71 is turned on, an alarm means is activated to warn an operator or the like.
[0035]
In other words, when the tip (rear end) portion is tilted when the load receiving platform 6 is moved up and down, the tilt link 2 always swings from the retracted position to the release position as shown in FIG. By detecting the swing of the tilt link 2 with the detector 71, it is indirectly detected that the load receiving platform 6 is tilted.
[0036]
For example, a buzzer or a lamp is used as the alarm means, and the operator is informed of the situation by sounding the buzzer or turning on the lamp.
[0037]
When the load receiving platform 6 is tilted during the up-and-down movement, the alarm means is activated to warn the operator of the situation and alert the operator, so that the load is moved inadvertently or the load falls. Can be prevented and safe work can be performed.
[0038]
Further, in the warning device 7 configured as described above, the alarm means operates similarly when the cargo receiving platform 6 is tilted with grounding, but the cargo receiving platform 6 is normally tilted with respect to the operator. Since it is possible to call the operator's attention by giving a warning even during the operation, it is preferable in terms of safety. In addition, when the receiving stand 6 performs normal tilting operation on the ground, the detection by the detector 71 can be invalidated so that the warning device 7 is not operated.
[0039]
In the present embodiment, the proximity switch is described as an example of the detector 71. However, the detector 71 is not limited to the proximity switch, and can detect the swing state of the tilt link 2 such as a photoelectric switch or a limit switch. Anything is acceptable.
[0040]
Further, the loading platform lifting device X is not limited to the one provided in the freight vehicle as in the present embodiment, but is a facility for loading and unloading cargo between the ground and a loading platform located at a predetermined height from the ground. May be provided.
[0041]
【The invention's effect】
As described above, according to the warning device in the load receiving table lifting apparatus of the present invention, the detector is provided for detecting when the tip end portion is inclined downward during the lifting operation of the load receiving table. The alarm means is activated based on the detection of the alarm, so that when the load receiving platform is tilted during the raising / lowering operation, the alarm means is activated to warn the operator of the situation and call attention. It is possible to prevent accidents such as accidental movement of the load or dropping of the load, and safe work can be performed.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a side view showing a schematic configuration of a load receiving table lifting device in which a load receiving table is in a lying state at its highest position.
FIG. 2 is a side view showing a schematic configuration of a load receiving table lifting device in which the load receiving table is moved up and down at the lowest position.
FIG. 3 is a side view showing a schematic configuration of the load receiving table lifting device in which the load receiving table is tilted at the lowest position.
FIG. 4 is a side view showing a schematic configuration of a load receiving table lifting device in which the load receiving table is raised at the highest position.
FIG. 5 is a side view showing a warning device.
FIG. 6 is a side view showing an abnormal state in which the warning device is activated due to the inclination of the load receiving platform.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cargo vehicle 15 Loading platform 2 Tilt link 6 Loading platform 7 Warning device 71 Detector G Ground (ground)
X Loading platform lifting device

Claims (2)

A load receiving platform is provided between the ground and a loading platform located at a predetermined height from the ground so as to be movable up and down via a link mechanism, and the cargo receiving platform is tilted so that its tip is grounded on the ground. In the load receiving table lifting device configured to do so, a detector is provided for detecting when the tip of the load receiving table is tilted downward during the lifting operation of the load receiving table, and alarm means based on the detection of the detector A warning device in a load receiving table lifting device, wherein the warning device is configured to operate.   The link mechanism includes a tilt link for tilting the load receiving platform on the ground so that the tip of the load receiving platform is in contact with the ground. The warning device in the load receiving table lifting device according to claim 1, wherein the warning device is configured.

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