JPH0427704Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a loading platform elevating device for a loading vehicle, which is provided at the rear of the loading vehicle and is used when loading and unloading cargo onto the loading platform.

(Prior Art) Conventionally, as shown in FIG. 3, in a loading platform elevating device for a cargo handling vehicle, a rotating shaft n is fixed to a frame a fixed to the rear left and right sides of a vehicle body frame k. A rotating plate b is fixed to n. The base end of the tension link c is rotatably supported by the frame a, and the base end of the lift arm d is rotatably supported by the rotating plate b. The tip of the lift arm d is rotatably supported by the lower end of the column e,
On the other hand, the tip of the tension link c is rotatably supported by the upper end of the support column e. Therefore, the rotating plate b, the tension link c, the lift arm d, and the support column e constitute a parallelogram link mechanism. Furthermore, a forcing cam h that is detachable from a restraining member g fixed to the upper surface of the lift arm d is rotatably supported on the rotary plate b. The members configured as described above are provided symmetrically on both left and right sides at the rear of the vehicle body frame k. The cargo receiving platform (hereinafter referred to as the tailgate) f is pivotally supported by the lower ends of the columns e, and the link mechanism is rotated via the rotating arm j and rotating shaft n by the expansion and contraction of the lifting cylinder i. It is designed to move up and down. When the tailgate f moves up and down from just before the ground to the height of the loading platform m, the forcible cam h is engaged with the restraining member g, so the tailgate f
moves up and down while maintaining a horizontal position. Also,
When the tailgate f reaches the ground (the lower end of the support column e comes into contact with the ground), the forced cam h separates from the restraining member g, and the lift arm d is pulled in the direction of arrow P in FIG. Due to the interaction with the tailgate f's own weight, the lower end of the support column e slid on the ground, and the tailgate f was tilted so that its tip was in contact with the ground.

(Problem to be solved by the invention) However, the tilting of the tailgate as in the conventional case is such that when the tailgate reaches the ground, the forced cam separates from the restraining member and the lift arm is pulled in the direction of arrow P. This is done by the lower end of the pillar touching the ground sliding on the ground due to the interaction between the tailgate's own weight and the tailgate's own weight. For this reason, when the tailgate is not loaded with cargo, or when the ground is soft such that the bottom end of the column that touches the ground is buried in the ground, the tip of the tailgate will not go down until it makes contact with the ground. There was a problem with the tailgate not tilting sufficiently.

(Means for Solving the Problems) The loading platform elevating device for a cargo handling vehicle of the present invention is provided with a link mechanism including a tension link, a lift arm, and a support at the rear of the body frame of the cargo handling vehicle, and an appropriate drive In the loading platform lifting device, the loading platform pivotably supported on the pillar is moved up and down by rotating a link mechanism through the device, wherein the pillar has an upper end portion of a tilting member that is rotatable. The lower end of the tilting member is arranged to protrude downward from the lower end of the support column.

(Function) A tilting auxiliary member protruding downward from the lower end of the column is rotatably supported at an appropriate position on the column. Therefore, as the tailgate descends, this tilting assisting member comes into contact with the ground, and the lower end of the support column and the tailgate are held at a position slightly apart from the ground.
The tailgate tilts smoothly without the lower end of the support column sliding on the ground due to the movement of the lift arm and the tailgate's own weight.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the loading platform elevating device includes a link mechanism formed symmetrically on both left and right sides at the rear of the vehicle body frame 1, and a drive device for driving the link mechanism. The tailgate 16 moves up and down between the cargo bed of the vehicle and the ground. Hereinafter, the structure of the link mechanism and drive device provided on one of the left and right sides at the rear of the vehicle body frame 1 will be described, and members provided symmetrically will be denoted by the same reference numerals.

A rotating shaft 4 is horizontally supported on the lower part of a frame 2 fixed to one rear side of the vehicle body frame 1, and a rotating plate 3 is fixed to the tip of the rotating shaft 4 protruding outward from the frame 2. There is. A base end of a lift arm 6 is rotatably supported on the rotating plate 3, and a base end of a tension link 7 is rotatably supported on the upper part of the frame 2. The tip of the tension link 7 is rotatably supported on the upper end 11 of the column 8, and the tip of the lift arm 6 is supported on the column 8.
It is rotatably supported by the lower end portion 12 of. Therefore, the lift arm 6, tension link 7, support column 8, and rotary plate 3 constitute a parallelogram link mechanism. Further, on the rotating plate 3, a restraining member 13 is fixed to the upper surface of the lift arm 6 near the base end.
A forcing cam 15 that can be engaged with and detached from the cam 15 is rotatably supported. Further, an elevating cylinder 5 is provided on the frame 2 as a driving device for driving the link mechanism, and a rod end of the elevating cylinder 5 is connected to the rotating shaft 4 via a rotating arm 9. The left and right sides of the rear end of the tailgate 16 are pivotally supported on the inner surfaces of the lower end portions 12, 12 of the pillars 8, 8, which are provided symmetrically.
is held perpendicular to the support column 8 (horizontal to the ground) by a holding member 21. Therefore, as the link mechanism rotates, the tailgate 16 is moved up and down while maintaining a horizontal state.

A tilting auxiliary member 18 is rotatably provided at an appropriate position on the support column 8 of the above-mentioned loading platform lifting device. In this example, the upper end 19 of the tilting assisting member 18
is rotatably supported between the column 8 and the tension link 7 by a pin 17 that supports the column 8 and the tension link 7. Tilting auxiliary member 1
The lower end 20 of the support column 8 extends downward so as to protrude beyond the lower end portion 12 of the support column 8. When the tailgate 16 is lowered, the lower end 20 of the tilting auxiliary member 18 comes into contact with the ground, and the lower end portion 12 of the support support 8 extends downward. and tailgate 1
6 is held at a position slightly away from the ground. Further, a stopper 23 is provided on the support column 8 in a protruding manner, and comes into contact with the tilting assisting member 18 at the position where the tailgate 16 has finished tilting. Note that the tilting auxiliary member 18
The supporting position of the support column 8 is not limited to this example. The reference numeral 22 in the figure is a contact member that comes into contact with the lower surface of the lift arm 6 and transmits the movement of the rotary plate 3 to the lift arm 6, and 24 is a loading platform.

Next, the operation of the loading platform lifting device will be explained.

The tailgate 16 moves up and down as the lift cylinder 5 expands and contracts, and the rotary plate 3, lift arm 6, tension link 7, and column 8 that constitute a link mechanism rotate. First, tailgate 1
When the lift arm 6 moves up and down from just above the ground to the height of the loading platform 24, the forced cam 15 rotatably supported by the rotary plate 3 engages with the restraining member 13 fixed to the lift arm 6. The lift arm 6 is restricted from moving in the direction of tilting the tailgate 16. Therefore, the tailgate 16 moves up and down while maintaining a horizontal state.

Next, when the tailgate 16 reaches the ground,
The forced cam 15 is separated from the restraining member 13, and due to the rotation of the rotary plate 3, the lift arm 6 is pulled in the direction of arrow Q in FIGS. 1 and 2, and the weight of the tailgate 16. The interaction causes the tip of the tailgate 16 to tilt so as to touch the ground. At this time, the lower end 20 of the tilting auxiliary member 18 pivotally supported by the support column 8 is in contact with the ground;
This tilting auxiliary member 18 allows the lower end 1 of the column 8 to
2 and the tailgate 16 are held at a position slightly apart from the ground. Therefore, the lower end 12 of the support column 8 does not touch the ground, and the tilting auxiliary member 18
The pillar 8 tilts about the pin 17 that supports the pillar 8, and the tailgate 16, which is pivotally supported by the pillar 8, also begins to tilt smoothly. Furthermore, when the tailgate 16 tilts, the stopper 23 protruding from the support column 8 comes into contact with the tilting assisting member 18, and the tailgate 16 completes its tilting (see FIG. 2).

(Effects of the invention) As described above, according to the loading platform elevating device for a cargo handling vehicle of the present invention, when the tailgate is lowered close to the ground, the lower end of the tilting auxiliary member supported by the pillar By coming into contact with the ground, the lower end of the column and the tailgate are held at a position slightly away from the ground, and the tailgate can be tilted without the lower end of the column sliding against the ground as in the conventional case.
To enable a tailgate to tilt smoothly and reliably even when no cargo is loaded on the tailgate or when the ground is soft.

[Brief explanation of drawings]

Figures 1 and 2 show the loading platform lifting device of the cargo handling vehicle of the present invention, Figure 1 is a perspective view showing the loading platform lifting device installed at the rear of the vehicle, and Figure 2 shows the tailgate reaching the ground. , a schematic explanatory view showing a tilting operation, and FIG. 3 is a perspective view showing a conventional loading platform elevating device for a cargo handling vehicle. DESCRIPTION OF SYMBOLS 1... Body frame, 5... Elevating cylinder, 6... Lift arm, 7... Tension link, 8... Strut, 12... Lower end, 16... Tail gate, 1
8...Tilt assisting member.

Claims (1)

[Scope of utility model registration claim] Tension link at the rear of the body frame of the cargo handling vehicle,
A cargo receiving platform is provided with a link mechanism including a lift arm and a support column, and by rotating the link mechanism via a suitable drive device, a cargo receiving platform pivotally supported by the support column is moved up and down. In the apparatus, an upper end of a tilting member is rotatably supported on the support, and a lower end of the tilting member is arranged to protrude downward from a lower end of the support. lift device.