JPH09301043A - Load-receiving platform elevating/lowering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a load-receiving platform elevating/lowering device with no fear of the interference of its two parallel links and the like with a packing box and a vehicle frame, and capable of being reliably and simply housed in whole under the packing box. SOLUTION: A load-receiving platform elevating/lowering device 2 has its load receiving platform 7 connected in a elevatable and lowerable manner through two parallel links 4 and 5 to an attached member 3 provided on the bottom end edge of a packing box 1. The two parallel links 4 and 5 are pivotally supported at their base ends by the attached member 3 and at their tip ends by a bracket 71 fixed on the halfway part of a side edge of the load receiving platform 7, and their pivotally-supported positions by the attached member 3 are projected outside the end edge of the packing box 1. The attached member 3 is disposed as to be movable along a guide rail 12 provided on the bottom of the load cage 1 toward the inward side of the load cage 1, while the load receiving platform 7 is structured as to be folded at its halfway part in its side edge. The folded load receiving platform 7 and the two parallel links 4 and 5 can be housed under the packing box 1 though the movement of the attached member 3.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load receiving platform elevating device.

2. Description of the Related Art Conventionally, a mounting member is provided at the lower rear end of a luggage box mounted on a vehicle or the like, and the base ends of two parallel links are pivotally supported by the mounting member and two parallel links are provided. The tip of the link is pivotally supported by the base end of the load receiving platform, and the parallel link is rotated up and down by a driving device such as a hydraulic cylinder to hold the load receiving platform in a horizontal state. There is provided a load receiving platform elevating device for elevating and lowering the device (see, for example, JP-B-55-34004).

However, in the above-mentioned prior art, the parallel link, which is pivotally supported by the mounting member, is located inward of the rear end of the luggage box and at the same time. Since the base end of the platform is pivotally supported by the tip of the parallel link, the parallel link,
In particular, there was a problem that the upper link on the upper side interferes with the rear end of the packing box, and it was necessary to devise the shape of the upper link. Moreover, even if the pivot of the parallel link pivotally supported by the mounting member is arranged so as to project outward from the rear end of the packing box, the parallel link is positioned vertically when the load cradle is raised to the maximum due to the positional relationship of the parallel links. Therefore, there is a problem that the parallel link mechanism is unbalanced due to the imbalance of the parallel link mechanism.

According to a first aspect of the present invention, there is provided a lifting device for lifting and lowering a load receiving platform which is vertically movable via two parallel links to a mounting member provided at a bottom edge of a load box. In the cargo cradle lifting device configured, the two parallel links have their base end portions pivotally supported by the mounting member, and their tip end portions pivotally supported by a bracket fixed to a middle portion of a side edge of the cargo bearer. The two parallel links to the mounting member are arranged so that the pivotal support positions of the two parallel links project outward from the edge of the luggage box. According to a second aspect of the present invention, in the device for raising and lowering a load carrier, the mounting member is provided movably inward of the load container along a guide rail provided at the bottom of the load container, while the load receiver is provided with side edges. The load receiving base and the two parallel links, which are configured to be foldable in the middle and folded by the movement of the mounting member, are configured to be stored below the load box. According to a third aspect of the present invention, in the device for raising and lowering a cradle, the upper link arranged above the two parallel links is configured to be bendable downward in a V shape in the middle thereof. By changing the refraction angle of the link, the length between the both ends of the pivot is variable. In the load receiving platform elevating / lowering device according to claim 4 of the present invention, the upper link is formed such that the end portions of the two link members are pivotally supported at the upper portion and the lower portions of the end portions are notched in a mountain shape. The two link members are arranged in a substantially straight line by the repulsive force of the urging member connected between the lower parts of the link members, and the end portions formed by cutting in the mountain shape repel each other. The two link members are configured so as to be bent downward in a V shape by matching against a force.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic overall configuration of a loading platform raising / lowering device according to the present invention. In FIG. 1, 1
Is a luggage box mounted on, for example, a vehicle frame 11 of a vehicle, and a luggage cradle lifting device 2 is provided at the lower rear end of the luggage box 1. The loading platform elevating / lowering device 2 includes a mounting member 3 provided on a vehicle frame 11, and two parallel links including an upper link 4 and a lower link 5 whose base ends are pivotally supported by the mounting member 3, respectively. It is composed of a load receiving stand 7 provided at the ends of two parallel links. The mounting member 3 is mounted on the vehicle frame 11
It is provided movably in the front-rear direction along a guide rail 12 arranged in the front-rear direction at the rear end portion. For more information,
Two upper guide rollers 31 and 1 provided on the mounting member 3
The lower guide roller 32 and the lower guide roller 32 are arranged so as to sandwich the guide rail 12 from above and below.
When the guide rails 1 and 32 roll on the guide rail 12, the mounting member 3 smoothly moves back and forth. At the rear end of the guide rail 12, the pivot point of two parallel links pivotally supported by the mounting member 3 when the mounting member 3 moves to the rearmost position of the guide rail 12 is the rear end of the packing box 1. The length is set to project from. Further, the mounting member 3 is provided with a moving means such as a handle (not shown) for moving the mounting member 3 back and forth along the guide rail 12 by an operator's operation. The mounting member 3 may be moved back and forth by a hydraulic cylinder, a drive motor, or the like, instead of manually. As described above, the base links of the upper link 4 and the lower link 5 are pivotally supported 41 and 51 on the mounting member 3, respectively. When the mounting member 3 moves to the rearmost position of the guide rail 12, Pivot 41,
The position of 51 is provided so as to project from the rear end of the luggage box 1. Further, the respective tip portions of the upper link 4 and the lower link 5 are provided with a bracket 71 provided at a middle portion of a side edge of the load receiving base 7.
It is pivoted 42 and 52. The upper link 4 is configured to be bendable in the middle. Specifically, in the upper link 4, the ends of the two link members 4a and 4b are pivotally supported at the upper part, and the two link members 4a and 4b are also supported.
Edges 4a1 and 4b1 between the ends of a and 4b are formed by cutting in a mountain shape. A gas spring (biasing member) 6 is continuously provided below the two link members 4a and 4b thus formed, and the two link members 4a and 4b are connected to each other. 6 are arranged in a substantially straight line by the repulsive force of 6, and the edges 4a1 and 4b1 of the end portions formed by cutting in a mountain shape are matched against each other against the repulsive force of the gas spring 6. It is configured to be bent in a shape (see FIG. 2). That is, by arranging the two link members 4a and 4b from the downward V shape to the substantially linear shape, the length between both end pivots pivotally supported by the attachment member 3 and the load receiving base 7 becomes long. Further, although not shown, a telescopic rod of a lift cylinder provided on the mounting member is connected to the upper link 4 through an arm member, and the telescopic operation of the lift cylinder rotates the upper link 4 up and down. When the upper link 4 is vertically rotated, the lower link 5 is also similarly rotated, and the load receiving base 7 can be moved up and down. The load receiving base 7 is formed into a relatively thin plate-like body as a whole by the front end side member 7a and the base end side member 7b, and the base end side member 7b.
The bracket 71 is fixed to the tip of the bracket. Further, the distal end side member 7a and the proximal end side member 7b are the upper hinge 7
The front end side member 7a is foldable in two on the upper surface of the base end side member 7b by 2. A grounding roller 73 is arranged so as to project from the bottom of the base end of the base end side member 7b.
Support when the vehicle reaches the ground, and the tip side member 7a
The lower surface 74 of the tip is formed in a wedge shape, and when the load receiving platform 7 reaches the ground, the tip is grounded on the ground without a step. Next, the operation of the load receiving platform elevating device configured as described above will be described. First, as for loading and unloading of luggage by the cargo receiving stand 7, the mounting member 3 is moved to the rearmost position of the guide rail 12 as shown in FIGS. After arranging the side member 7b on the same plane, the upper cylinder 4 is rotated by the expansion and contraction operation of the lift cylinder, so that the load receiving stand 7 is placed on the ground and the cargo box 1.
It is moved up and down with respect to the floor surface 1a. At this time, the receiving stand 7
Between the highest position, which is indicated by the two-dot chain line in FIG. 1 on the same plane as the floor surface 1a of the load box 1, and the position where the ground roller 73 of the load carrier 7 shown in FIG. The upper link 4 is in a state of being bent in a dogleg shape against the repulsive force of the gas spring 6 due to the weight of the load receiving stand 7 or the like. For this reason, the upper link 4 and the lower link 5 are
1, 51, 42, and 52 rotate up and down while holding the parallelogram, and as a result, the load receiving base 7 moves up and down while holding the horizontal. Then, when the loading platform 7 is raised to the highest position, the base end of the loading platform 7 is placed close to the rear end of the floor surface of the packing box 1, and the loading platform 7 and the floor of the packing box 1 are placed. Surface 1
The luggage can be transferred to and from a smoothly. At this time, the pivotal positions of the base ends of the upper link 4 and the lower link 5 pivotally supported by the mounting member 3 are arranged so as to project rearward from the rear end of the luggage box 1 as shown in FIG. In addition, since the respective tip portions of the upper link 4 and the lower link 5 are pivotally supported by the middle portion of the side edge of the load receiving base 7 via the bracket 71, the entire upper link 4 and the lower link 5 are 1 is arranged rearward of the rear end of the packing box 1
There is no danger of interfering with the vehicle frame 11 and the shape of the upper link 4 and the like need not be devised at all. In addition, the tip ends of the upper link 4 and the lower link 5 are connected via the bracket 71 to the load receiving base 7
Since it is pivotally supported in the middle of the side edge of the load receiving base 7, the load receiving base 7 can be made lighter in weight than the conventional one that is pivotally supported at the base end of the load receiving base 7. Next, when the ground roller 73 of the load receiving base 7 is grounded to the ground, the repulsive force of the gas spring 6 and the moment force acting on the tip of the load receiving base 7 are combined to change the upper link 4 from the dogleg shape to the straight state. Change, which allows both ends of the upper link 4 to pivot 4
The length between 1 and 42 becomes long, and the state of the parallelogram is broken. As a result, the tip of the receiving table 7 tilts downward, and touches the ground. As a result, the transfer of the load between the load receiving table 7 and the ground can be smoothly performed. Also, the receiving stand 7
When the vehicle is raised from the ground to the floor surface 1a of the luggage box 1, the cargo cradle 7 tilted by the operation opposite to the above operation is held in a horizontal state and is moved up and down. In this way, by simply changing the upper link 4 from the bent state to the straight state or from the straight state to the bent state, the loading platform 7 on the ground can be changed.
Can be tilted, and can be moved up and down while the load receiving base 7 is held horizontally. When the loading and unloading of the load by the load receiving platform elevating device 2 is completed in this way, as shown in FIG. 3, the upper link 4 is rotated to a position where the lower link 5 becomes substantially horizontal, and the tip of the load receiving platform 7 is rotated. The side member 7a is folded in two on the upper surface of the base end member 7b. Then, in this state, the mounting member 3 is moved forward by a drive source such as a hydraulic cylinder or the like manually, so that the entire loading platform elevating device 2 is stored under the floor of the loading box 1 (see the alternate long and short dash line in FIG. 1). ). Although not shown, a cover body is provided on the vehicle frame 11 to laterally cover the loading platform raising / lowering device 2 stored as described above, and the loading platform raising / lowering device 2 is protected by the cover body. Stored as state.

According to the load receiving platform raising / lowering device of the first aspect of the present invention, the base ends of the two parallel links are pivotally supported by the mounting member, and the distal ends are provided at the middle portions of the side edges of the load receiving base. By pivotally supporting the fixed bracket and arranging the pivotal support positions of the two parallel links to the mounting member at positions projecting outward from the edges of the packing box, Since the whole is placed behind the rear end of the luggage box, there is no risk of interfering with the luggage box or the vehicle frame, and there is no need to devise the shape of the two parallel links or the like. According to the second aspect of the present invention, the mounting member is provided movably inward of the luggage box along the guide rail provided at the bottom of the luggage box, while the loading tray is provided on the side. Since the load receiving tray and the two parallel links that are folded by the movement of the mounting member can be stored under the load box, the entire load receiving tray lifting device can be securely and easily constructed. Can be stored below the packing box. According to the load receiving platform raising / lowering device of the third aspect of the present invention, the upper link arranged on the upper side of the two parallel links is configured to be bendable downward in the shape of a dogleg at its midpoint. By changing the refraction angle of the upper link and making the length between both ends pivotally variable, the length of the upper link is made longer on the ground than the lower link, so that the tilting of the load receiving platform can be easily performed. According to the loading platform elevating / lowering device of claim 4 of the present invention, the upper link pivotally supports the end portions of the two link members at the upper portion, and forms the lower portions of the end portions in the shape of a mountain, The two link members are arranged in a substantially straight line by the repulsive force of the urging member connected between the lower portions of the link members, and the end portions formed by cutting in the mountain shape are used as the repulsive force of the urging member. By aligning against each other and constructing the two link members to bend downward in a V shape, a simple mechanical structure
The loading platform can be tilted on the ground, and can be moved up and down while horizontally holding the loading platform between the ground level and the floor of the packing box.

[Brief description of drawings]

FIG. 1 is a side view showing an overall schematic configuration of a loading tray elevating device according to the present invention.

FIG. 2 is a side view for explaining the operation of the load receiving platform lifting device.

FIG. 3 is a side view for explaining the operation of the load receiving platform lifting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 packing box 12 guide rail 2 loading platform lifting device 3 mounting member 4 upper link 4a, 4b link member 6 gas spring (biasing member) 7 loading platform 71 bracket

Claims (4)

[Claims] 1. A load receiving platform elevating device in which a load receiving platform is configured to be vertically movable via two parallel links to a mounting member provided at a bottom edge of a load box, wherein the two parallel links are bases. An end portion is pivotally supported by the mounting member, and a tip end portion is pivotally supported by a bracket fixed to a middle portion of a side edge of the load receiving base, so that the pivotal support positions of the two parallel links to the mounting member are the load positions. A device for lifting and lowering a cradle characterized by being arranged at a position projecting outward from the edge of the box. 2. The mounting member is movably provided on the inner side of the luggage box along a guide rail provided at the bottom of the luggage box, while the load receiving base is configured to be foldable in the middle of the side edge. 2. The load-carrying platform lifting device according to claim 1, wherein the load-carrying base and the two parallel links folded by the movement of the mounting member are configured to be retractable under the load box. 3. The upper link of the two parallel links, which is arranged on the upper side, is configured to be bent downward in a dogleg shape in the middle thereof, and the refraction angle of the upper link is changed so that both ends are pivoted. The load receiving platform raising / lowering device according to claim 1 or 2, wherein the length between the branches is variable. 4. The upper link has two link members whose ends are pivotally supported at the upper part, and the lower parts of the ends are notched in a mountain shape, and are connected between the lower parts of these link members. By the repulsive force of the urging member, the two link members are arranged in a substantially straight line, and the end portions formed by cutting in a mountain shape are matched against each other against the repulsive force of the urging member. The load platform elevating / lowering device according to claim 3, wherein the two link members are configured to be bent downward.