JPH054437Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an elevating device that is attached to the rear of a truck body, such as a freight vehicle, to facilitate the loading and unloading of cargo by raising and lowering a platform.

(Prior Art and Problems) Conventionally, elevating devices installed on freight vehicles generally have a structure in which a platform is raised and lowered via a parallel link mechanism, and when the freight vehicle is running, the platform is also used as a rear gate, or It was folded up and stored under the floor of the car.

By the way, when a box-shaped vehicle body (vanhode) is installed as a truck body, the rear door of the box-shaped vehicle body is a double door, so it is better to change the door structure by making the platform foldable and storing it under the floor. This is convenient because there is no need for it.

However, in the conventional elevating device of the platform underfloor storage structure, the platform in the folded state must be stored in the limited space under the floor of the vehicle body, so the arm of the elevating link mechanism and the platform in the folded state are close to parallel to each other. It was configured so that it was stored in a state. Therefore, when starting cargo handling work, it is necessary to lower the end of the arm of the lifting link mechanism, and manually lift the folded platform, which overlaps the arm and tilts toward the back, and rotate it forward. This caused the workers to have a bad posture and required a lot of effort.

(Means for Solving the Problems) In view of the above points, the present invention allows the platform to be unfolded horizontally by providing a mechanism for raising the folded platform in conjunction with the lowering of the arm of the lifting link mechanism. The purpose of the present invention is to provide an elevating device that facilitates the work.

The present invention includes a fixed support member fixed to the underfloor of a vehicle body, a rotary shaft rotatably supported by the fixed support member and rotationally driven by a drive means, and one end on each side of the rotary shaft. a main arm that is attached and receives rotational driving force from the rotating shaft; a sub-arm that forms a parallel link for lifting and lowering together with the main arm and has one end pivoted to the fixed support member side; the other end of the arm is a first pin, the other end of the sub-arm is pivotally connected to the lower end of the vertical link body by a second pin, and the first pin is pivotally connected to the main arm and the vertical link body. and a sub-platform that is foldably connected to the main platform via a hinge, the main platform being folded in an inverted direction about the first pin. The wire rope is a tension member that can be rotated and stored under the floor of the vehicle body, and further includes a sheave supported by each of the first and second pins, and an extension spring and a wire rope connected in series. is installed on each sheave, one end of the tension member is locked to the main arm side, the other end of the tension member is locked to the main platform side, and the extension of the extension spring is A member is provided for regulating the tension member to a certain amount or less, and the distance between the main arm side fixing point of the tension member and the sheave on the lower side increases as the vertical link body descends. The above-mentioned problems of the prior art are solved by the configuration in which the main platform is raised up.

(Function) In the elevating device of the present invention, the folded main platform and sub-platform are stacked on the elevating link mechanism consisting of the main arm and the sub-arm, and the elevating link mechanism is placed in the raised position to store it under the floor. In the cargo handling preparation state in which the tips of each arm of the lifting link mechanism are lowered, the main platform is moved from a specific point on the main arm to a specific point on the vertical link body pivotally attached to the tip of each arm. Focusing on the fact that the distance to a specific point changes, one end of a tension member consisting of an extension spring and a rope connected in series is fixed to the main arm, the other end is fixed to the main platform, and the tension member is An intermediate portion of the tension member passes through a sheave provided on the vertical link body, so that the tension member raises the folded platform when each arm of the lifting link mechanism is lowered. I have to.

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

In FIGS. 1 and 2, the lifting device is attached to the rear of the vehicle body (for example, a box-shaped vehicle body) 1 of a freight vehicle, and as shown in FIG. 2, it is fixed to the vehicle chassis 2 and serves as a bearing. A fixed support member 4 having a round pipe 3, a rotating shaft 5 that passes through the round pipe 3 of the fixed supporting member 4 and is rotatably supported, and a rotating member 7 fixed to both sides of the rotating shaft 5. , and a main arm 8 and a sub-arm 9 that form a parallel link mechanism for lifting and lowering. The rotating shaft 5 is rotatably driven by a mechanism using a hydraulic cylinder.

One end of the main arm 8 is pivotally connected to the rotating member 7 by a pin 15, and when the rotating member 7 attempts to rotate counterclockwise due to the left rotation of the rotating shaft 5, the main arm 8 is rotated. It rotates together with the moving member 7 to raise the tip. Further, when the rotating shaft 5 rotates clockwise, the main arm 8 rotates together with the rotating member 7 until its tip touches the ground, lowering the tip.

One end of the sub-arm 9, which forms a parallel link for lifting and lowering together with the main arm 8, is attached to the fixed support member 4.
It is pivotally connected to a bracket 11 fixed to the round pipe 3 with a pin 12.

The other ends, ie, the tips, of the main arm 8 and the sub-arm 9 are pivotally connected to a vertical link body 20, respectively. That is, the upper end of the vertical link body 20 together with the main arm 8 is pivotally connected by a pin 21 to a bracket 23 fixed to the rear end surface of the main platform 30. In addition, the sub arm 9
The tip of the vertical link body 20 is pivotally connected to the lower end of the vertical link body 20 with a pin 25.

A sub-platform 3 is connected to the main platform 30 via a foldable hinge.
1 are connected to form a foldable platform, and both platforms 30 and 31 form one horizontal plate when extended.

Now, at the start of cargo handling work, both platforms 3
0 and 31 are erected as the arms 8 and 9 descend to facilitate the unfolding of the folded platform.
0 is installed between the intermediate portion of the main arm 8 near the tip and the tip portion of the main platform 30. That is, one end of the wire rope 36 is locked and fixed to the protrusion 37 on the side surface of the main arm 8, and the other end of the wire rope 36 is connected to the main platform 3.
It is connected to the head of a bolt-like member 39 that slidably passes through a guide stopper 38 fixed to the side surface of the bolt. A nut 41 serving as a stopper is screwed to the tip of the bolt-like member 39.
The coil spring 35 is connected between the tip of the bolt-like member 39 and a hook 42 fixed to the main platform 30. The guide stopper 38 and a bolt-like member 39 having a nut 41 fixed to the tip function as a member that restricts the expansion of the coil spring 35 to a certain amount or less. moreover,
A pin 21 passing through the upper end of the vertical link body 20
A sheave (pulley) 44A is supported by a pin 25 passing through the lower end, and a sheave 44B is supported by a pin 25 passing through the lower end, and an intermediate portion of the wire rope 36 is stretched between the grooves of these sheaves 44A and 44B.
Note that the wire rope 36 is kept under tension by the coil spring 35, and the sheaves 44A, 4
It is designed so that it does not fall out of the groove of 4B.

Next, the operation of the lifting device shown in the embodiment will be explained.

As shown in position A in FIG.
1 is folded and stored, the sheave 44 can be accessed from the hook 42 on the main platform 30 side.
A, 44B to the protrusion 37 on the side of the main arm 8 is the shortest distance (protrusion 37, pin 2
1. The triangle formed by the three points of the pin 25 is the most oblate), the tension of the tension member 40 is the lowest, and the coil spring 35 is in the most compressed state. At this time,
There is almost no force trying to raise the platform.

When the main arm 8 is rotated clockwise from position A in FIG. 1 and the tips of the main arm 8 and sub-arm 9 are lowered, the positional relationship between the lower part of the vertical link body 20 and the main arm 8 changes. result,
Lower sheave 44B over which wire rope 36 is stretched
The distance from the main arm side protrusion 37 to the main arm side protrusion 37 gradually becomes longer, and as a result of the bolt-like member 39 being pulled, the nut 41 reaches the main platform 30.
Since the length of the tensioning member 40 does not change after this point, the main platform 30 contacts the guide stopper 38 fixed to the tensioning member 4.
0 gradually stands up.

When the arms 8 and 9 are in a lowered tip landing state as in position B in FIG.
That is, the length from the protrusion 37 to the sheave 44B is at its maximum, and the main platform 30 is raised almost vertically by the tension member 40. From this state, the operator can very easily move the main platform 30 to the C position. Lay down the main platform 30 horizontally,
Furthermore, the sub-platform 31 at the tip can be expanded horizontally. The upright state of the platform can be easily adjusted by adjusting the position of the nut 41 that serves as a stopper.

Note that since the arms 8 and 9 form a parallel link mechanism, the main arm 8 is rotated by the rotational driving force of the hydraulic cylinder, that is, the rotation of the rotating member 7, and the vertical link body 20 is held in a vertical state. The main platform 30 and the sub-platform 31 in the unfolded state supported horizontally by the vertical links 20 can be raised and lowered to carry out cargo handling work.

(Effects of the invention) As explained above, according to the elevating device of the present invention, the elevating link mechanism, the vertical link body pivotally attached to the tip thereof, and the vertical link body pivotably attached to the vertical link body and corresponding thereto. and a folding platform supported in a horizontal state in contact with each other, and the folding platform is folded and stored under the rear floor of the vehicle body. The tension member is engaged with the main arm of the lifting link mechanism, the other end is engaged with the main platform of the folding platform, and the intermediate portion of the tension member passes through sheaves at the upper and lower ends of the vertical link. Therefore, each arm of the elevating link mechanism is lowered by utilizing the fact that the distance between the main arm side fixing point of the tension member and the sheave becomes longer as the vertical link body descends. When the platform is folded, the tension member can raise the folded platform.

As a result, the folded platform can be unfolded horizontally with great ease, reducing the amount of effort required by the operator.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the lifting device according to the present invention, and FIG. 2 is a front view of the main platform and sub-platform folded and stored. DESCRIPTION OF SYMBOLS 1... Vehicle body, 3... Round pipe, 4... Fixed support member, 5... Rotating shaft, 7... Rotating member, 8... Main arm, 9... Sub arm, 20... Vertical link body, 30 ...Main platform, 31...
...Subplatform, 35...Coil spring, 3
6... Wire rope, 40... Tension member, 4
4A, 44B...Sheave.

Claims (1)

[Claims for Utility Model Registration] A fixed support member 4 fixed to the underfloor of a vehicle body, a rotating shaft 5 rotatably supported by the fixed supporting member and rotationally driven by a drive means, and the rotating shaft. A main arm 8 has one end attached to each side of the main arm 5 and receives rotational driving force from the rotation shaft, and the main arm 8 forms a parallel link for lifting and lowering together with the main arm 8, and one end is pivotally attached to the fixed support member side. a vertical link body 20 having the other end of the main arm 8 at its upper end pivoted by a first pin 21 and the other end of the sub-arm 9 pivoting at its lower end by a second pin 25; 1st pin 2
1, a main platform 30 is pivotally connected to the main arm and the vertical link body, and a sub-platform 31 is foldably connected to the main platform 30 via a hinge; The main platform 30 can be rotated in the inside out direction around the first pin 21 and stored under the floor of the vehicle body. Furthermore, the sheaves 44A and 44B are connected by the first and second pins 21 and 25. The wire ropes 36 of the tension members 40 are respectively pivotally supported and the tension springs and the wire ropes 36 are connected in series to each sheave 44.
A, 44B, one end of the tension member 40 is locked to the main arm 8 side, the other end of the tension member 40 is locked to the main platform 30 side, and the A member is provided to restrict the extension of the extension spring to a certain amount or less, and the distance between the main arm side fixing point of the tension member 40 and the lower sheave 44B increases as the vertical link body 20 descends. A lifting device characterized in that the main platform 30 is raised up by taking advantage of its length.