JP3883044B2 - Loading platform lifting device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a load receiving table lifting / lowering device that is mounted on a rear portion or a side portion of a truck and used for loading and unloading loads.
[0002]
[Prior art]
For example, in a conventional load receiving table lifting apparatus described in Japanese Patent Application Laid-Open No. 2001-39205, a pair of left and right arms provided on a vehicle body are rotated by a pair of left and right hydraulic cylinders to raise and lower the load receiving table. A connecting member is provided between the distal end portions of the arms, and the left and right arms are interlocked during the lifting operation. Each arm is supported by a pair of left and right support members provided on the vehicle body, and a spare tire carrier for holding a spare tire is attached to a central portion of an attachment member fixed between the support members.
[0003]
[Problems to be solved by the invention]
In addition to the load receiving device lifting device having the arm structure as described above, there is a load receiving device lifting device adopting a two-stage arm configuration of a base arm and a tip arm. If it is going to apply the attachment form of the above connecting members to the load receiving platform lifting apparatus adopting such a two-stage arm configuration, a connecting member is provided between the left and right tip arms, or between the left and right base arms. A connecting member will be provided. However, when a connecting member is provided between the left and right tip arms, the connecting member interferes with the base arm when the tip arm is folded so as to overlap the base arm. Similarly, when a connecting member is provided between the distal ends of the left and right base arms, interference with the distal arms occurs. On the other hand, when a connecting member is provided between the rear end portions of the left and right base arms, it is difficult to secure a spare tire mounting space.
[0004]
In view of the conventional problems as described above, the present invention is a load receiving platform lifting apparatus adopting a two-stage arm configuration of a base arm and a tip arm, in which the left and right arms are interlocked while avoiding interference between members, The purpose is to secure a spare tire mounting space.
[0005]
[Means for Solving the Problems]
The present invention relates to a load receiving base lifting device capable of lifting and lowering and storing / deploying a load receiving base by turning a pair of left and right base arms and a tip end arm provided on the vehicle body, for attaching the load receiving base lifting apparatus to the vehicle body side. A pair of left and right support members, a pair of cylinders for driving the pair of base arms, and a channel-shaped cross section, with the opening facing downward, between the pair of support members in the vehicle width direction a member mounting provided to be attached to the intermediate in the vehicle width direction of the mounting member, the chain is suspended through the opening, by a pressed against the spare tire to the lower end surface of the mounting member a spare tire carrier for holding this, the disposed through the interior of the mounting member, and connected to each other the pivot axes of the pair of base arm, said pair of base earth And those in which a connecting member integrally forms the rotation axis.
[0006]
In the load receiving platform lifting apparatus configured as described above, the pair of left and right base arms are interlocked with each other by the connecting member that integrally forms the rotation axis with the base arm. Further, since the connecting member is present at the rotation axis position of the base arm, the connecting member does not interfere with the base arm and the tip arm when the load receiving table is stored. In addition, an attachment member for passing the connecting member therein is provided between the pair of left and right support members of the load receiving platform elevating device, and a spare tire carrier is provided in the middle in the vehicle width direction , so that the space for attaching the spare tire is left and right. Secured between the base arms. Further, the spare tire is held by being pressed against the lower end surface of the mounting member by a chain suspended through the opening of the mounting member having a channel-shaped cross section.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a load receiving table lifting apparatus employing an arm structure according to an embodiment of the present invention will be described with reference to the drawings. FIGS. 1 and 2 are a rear view and a side view, respectively, showing the load receiving platform lifting / lowering device 1 attached to the lower part of the cargo box 102 at the rear part of the body 101 of the truck. In FIG. 2, brackets 2A are attached to both side surfaces of the chassis 104 behind the rear wheel 103, and a support member 2B is attached thereto. The load receiving table elevating device 1 is attached to the support member 2B. 2 is in a traveling state stored in the lower part of the vehicle body 101. As shown in FIG. In use, the vehicle is pulled out from the state of FIG. 2 to the rear of the vehicle body 101 as shown in the order of FIG. 3, FIG. 4, and FIG.
[0008]
Next, the structure of each part of the load receiving platform elevating device 1 will be described with reference to FIG. The load receiving platform lifting / lowering device 1 basically has a two-stage arm structure including a base arm (base lower arm 4, base upper arm 8) and a tip arm (tip lower arm 13, tip upper arm 16). is doing. A spare tire 37 is attached between the pair of left and right base arms (4, 8) (details will be described later).
In FIG. 4, the base lower arm 4 can be rotated within a predetermined range around a pin 5 provided at the left end as a fulcrum, and the pin 5 is supported by the support member 2B. The right end portion of the base lower arm 4 is connected to a base connecting member 7 via a pin 6 as an action point. On the other hand, the base upper arm 8 can be rotated within a predetermined range around the arm shaft member 9 integrally provided by welding at the left end as a fulcrum. The arm shaft member 9 has a pipe shape and is supported by the support member 2B. A right end portion of the base upper arm 8 is connected to the base connecting member 7 via a pin 10 as an action point. Here, assuming that the arm shaft member 9 and the pin 5 are a pair of upper and lower fulcrums A and B, and the pins 10 and 6 are action points C and D corresponding to the fulcrums A and B, respectively, the base lower arm 4 and the base connection The member 7 and the base upper arm 8 constitute a base link mechanism composed of unequal squares with A, B, C and D as four vertices, side CD longer than side AB, and side BD longer than side AC. Yes.
[0009]
The base upper arm 8 is connected to a hydraulic cylinder 30 (shown only in FIG. 4) as a driving device. When the base upper arm 8 is rotated by the supply of hydraulic pressure, the base lower arm 4 is also rotated accordingly. To do. The base upper arm 8 is formed by fixing two steel materials of the same shape arranged in the vehicle body width direction to each other by a channel material 11. The channel material 11 serves to reinforce the base upper arm 8 and also controls the rotation of the tip upper arm 16. That is, in the retracted state of FIG. 2, the tip portion (pin 17 side) of the tip end upper arm 16 comes into contact with the upper surface of the channel material 11, and the tip end top arm 16 further rotates counterclockwise. Is regulated.
[0010]
Next, in FIG. 4, the tip end lower arm 13 is pivotally attached to the base lower arm 4 by a pin 6 and is attached to be rotatable in a predetermined range in the counterclockwise direction from the illustrated position. The right end of the tip lower arm 13 is connected to the tip connecting member 15 via a pin 14 as an action point. Further, the L-shaped tip upper arm 16 is pivotally attached to the base upper arm 8 by a pin 10 and can be rotated counterclockwise within a predetermined range. Is detented. The right end of the tip upper arm 16 is connected to the tip connecting member 15 through a pin 17 as an action point. Here, assuming that the pins 17 and 14 are the action points E and F, respectively, the distal end lower arm 13, the distal end connecting member 15 and the distal end upper arm 16 are parallel four sides having C, D, E and F as four vertices. A tip end link mechanism having a shape is formed.
[0011]
In the base link mechanism (ABCD), the tip end link mechanism (CDEF), and the load receiving platform 18 supported by the tip end link mechanism, the position shown by the solid line in FIG. At the end.
Further, the distal end link mechanism (CDEF) can be folded as shown in FIGS. 3 and 2 by rotating counterclockwise with respect to the base link mechanism (ABCD).
[0012]
On the other hand, in FIG. 5, the load receiving stand 18 is also a foldable structure, and includes a main plate 19 and a sub plate 20. The sub-plate 20 can be rotated counterclockwise from the illustrated position with respect to the main plate 19 (see FIG. 4). The main plate 19 is attached so as to be able to turn counterclockwise from the illustrated position with the pin 17 as a support point. Further, the stopper 21 attached to the main plate 19 is in contact with the right end surface of the tip end connecting member 15. The guide plate 22 protruding from the left end of the main plate 19 serves to fill a gap between the floor surface of the load box 102 and the load receiving platform 18 when loading and unloading the load. The guide roller 23 engages with the load receiving table 18 when the load receiving table lifting device 1 is stored, and guides it. The guide roller 23 is rotatably supported by a guide roller support member 24 fixed to the support member 2B.
[0013]
Next, the raising / lowering mechanism of the load receiving stand 18 will be described. FIG. 6 is a side view showing in principle the load receiving platform 18 and an arm structure composed of a base link mechanism and a tip link mechanism for raising and lowering the load receiving table 18, and the reference numerals of the respective parts are the same as those in FIGS. 2 to 5. . The base link mechanism is represented by an unequal side rectangle ABCD, where A and B are fixed points and C and D are movable points. The tip link mechanism is represented by a parallelogram CDEF, and each vertex C, D, E, F is a movable point. When the base lower arm 4 and the base upper arm 8 are rotated within the range shown in the drawing, the distal end is connected to the rotating end side and is prevented from rotating in the clockwise direction with respect to the base upper arm 8. The upper arm 16 rotates integrally, and the tip end lower arm 13 also rotates following this. The side CD and the side EF are always parallel to each other, and the load receiving stand 18 always maintains a constant posture with respect to the side EF. Therefore, the inclination of the receiving tray 18 is determined by the inclination of the side CD. On the other hand, as long as the inclination of the side CD is constant, the posture of the load receiving stand 18 is constant and always lateral. For example, the load receiving stand 18 in the state shown in FIG. 3 is different from the state shown in FIG. 5 in that the sub-plate 20 is folded, but the inclination of the side CD is unchanged. Accordingly, the posture of the load receiving platform 18 (inclination of the main plate 19) is completely the same in the range shown in FIG. 3 and the state shown by the solid line in FIG.
[0014]
In addition, as shown in FIG. 6, the distal end link mechanism (CDEF) has an inclination angle steeper than the inclination angle of the base upper arm 8 at the rising end of the base upper arm 8, and is It plays a role of further pushing up the EF and the receiving platform 18. Therefore, it is possible to push up the load receiving platform 18 to a predetermined height while suppressing the rotation range of the base link mechanism (ABCD). In addition, it is possible to avoid interference between the base arm or the like and the load box 102 at the rising end of the load receiving platform. Conversely, at the descending end of the base upper arm 8, the distal end link mechanism has an inclination angle that is gentler than the inclination angle of the base upper arm 8, and suppresses the lowering of the side EF and the load receiving table 18 with respect to the side CD. Playing a role.
[0015]
In this embodiment, the lengths of the sides AB, CD, AC and BD of the base link mechanism (ABCD) are configured such that AB <CD and AC <BD. Such a magnitude relationship between two opposing sides affects the link operation.
FIG. 7 is a diagram showing how the size relationship between sides AB and CD in a link mechanism having an unequal side square affects the link operation, in addition to the actual arrangement shown in FIG. (A) shows the link operation when AC = BD and AB <CD, and (b) shows the link operation when AB> CD.
[0016]
In (a), in the state shown by the solid line, the sides AB and CD are both vertical, but the side CD is tilted to the left as shown by the two-dot chain line by raising the rotation side of the link mechanism. Further, the side CD is inclined to the right as the pivot side of the link mechanism is lowered. On the other hand, in (b), in the state shown by the solid line, the sides AB and CD are both vertical, but the side CD is inclined to the right as shown by the two-dot chain line by raising the rotation side of the link mechanism. . Further, the side CD is tilted to the left as the rotation side of the link mechanism is lowered. That is, in (a) and (b), the inclination direction of the side CD accompanying the rotation of the link mechanism is opposite.
Further, in (a), when AC> BD, the inclination angle of the side CD with respect to the vertical at the time of ascent and descent decreases. Conversely, when AC <BD, the inclination angle of the side CD with respect to the vertical at the time of ascent and descent increases. Further, in (b), when AC> BD, the inclination angle of the side CD with respect to the vertical at the time of ascent and descent increases. Conversely, when AC <BD, the inclination angle of the side CD with respect to the vertical at the time of ascent and descent decreases.
[0017]
Based on the above, based on the magnitude relationship between AB and CD (including the case where they are equal), an unequal-sided quadrilateral that further takes into account the magnitude relationship between AC and BD (including cases where they are equal) as necessary. By configuring the link mechanism, it is possible to adjust the inclination of the side CD with respect to the side AB that occurs as the link rotates to a desired level. In the present embodiment, as described above, the relationship of AB <CD and AC <BD is employed.
[0018]
Returning to FIG. 6, at the rising end of the base link mechanism (ABCD), the side CD and the side EF are inclined to the storage side of the load receiving platform 18 from the left side, that is, from the vertical line. In this state, the load receiving stand 18 is supported substantially horizontally. When the base link mechanism descends from this state, the side CD and the side EF tilt gently. At the descending end, the inclination angles of the side CD and the side EF are smaller than those at the ascending end, and the load receiving stand 18 is tilted. However, the side CD and the side EF are still inclined toward the storage side from the vertical line even at the descending end.
In this way, the tilting operation of the load receiving platform 18 is not performed separately from the lifting operation, but is performed integrally with the lifting operation. Therefore, a dedicated structure for the tilt operation is not necessary, and the structure is simple. Further, this tilting operation is performed very smoothly and does not involve an impact. Accordingly, it is possible to prevent the luggage from falling or falling. On the other hand, when moving from the descending end to the ascending end, similarly, the load receiving platform 18 changes its posture from the tilted state to the horizontal very smoothly.
[0019]
Next, the arm structure will be described in more detail. FIG. 8 is an exploded perspective view of an arm structure (an example on the port side, that is, the left side as viewed from the rear of the vehicle body). In the figure, the base upper arm 8 is composed of two plates as described above, and the tip end upper arm 16 composed of a single plate is connected between the ends of the two plates. On the other hand, the tip end lower arm 13 is composed of two plates, and between the ends of the two plates, a base lower arm 4 consisting of a single plate (however, pipe-like members are welded to both ends). The connection is made. Further, as described above, the above-described CD is connected by the base connecting member 7, and the EF is connected by the tip connecting member 15. That is, both the upper arm (base upper arm 8 and distal end upper arm 16) and lower arm (base lower arm 4 and distal lower arm 13) have a structure in which a two-plate arm and a single-plate arm are connected. It has become.
[0020]
FIG. 9 is a plan view (including a partially broken cross-sectional view) showing a detailed structure between the pair of left and right support members 2B of the vehicle body and the mounting position of the spare tire 37. FIG. FIG. In FIG. 9, the hydraulic cylinder 30 is pivotally mounted between a pair of side plates 2B1 constituting the support member 2B. The piston tip 30 a is pivotally attached to a drive arm 31 welded to the outer periphery of the arm shaft member 9. Therefore, the drive arm 31 rotates according to the expansion and contraction of the piston, and the arm shaft member 9 and the base upper arm 8 welded thereto rotate. The pair of left and right arm shaft members 9 are connected to each other by a pipe-shaped connecting member 32. Accordingly, the connecting member 32 and the arm shaft member 9 integrally form a pivot shaft with the base upper arm 8. As a result, the left and right base upper arms 8 and the base lower arm 4 that follows the left and right base upper arms 8 are rotated in an equal amount in conjunction with each other. Further, since the connecting member 32 serves as the pivot shaft of the base upper arm 8, the connecting member 32, the base arm (4, 8) and the tip arm (13, Interference with 16) can be avoided.
[0021]
On the other hand, between the pair of support members 2B between the pair of left and right base arms (4, 8), the mounting member 33 is horizontally mounted in the vehicle width direction and welded to the support member 2B at both ends. The attachment member 33 has a channel-shaped cross section (FIG. 10) and is hollow. A part of the connecting member 32 and the arm shaft member 9 is disposed through the inside of the mounting member 33.
A round hole 33a is provided in the middle of the attachment member 33 in the vehicle width direction (substantially the center in this example), and L-shaped brackets 34 are attached to both sides thereof. A spare tire carrier 35, which is a known unit, is attached to a pair of brackets 34. The spare tire carrier 35 incorporates a gear mechanism that winds up a chain and holds the spare tire 37. Specifically, the hook at the lower end of the chain 36 (FIG. 10) is hooked on the spare tire 37, a handle (not shown) is attached to the spare tire carrier 35 from the rear side of the vehicle body, the chain 36 is wound up, and the spare tire The spare tire 37 is held by pressing 37 against the lower end surface of the mounting member 33. As described above, since the connecting member 32 passes through the inside of the mounting member 33, it does not interfere with the spare tire mounting. Further, since the spare tire 37 is attached to the lower part of the attachment member 33, it is possible to avoid interference with the distal end arms (13, 16) when the load receiving table is stored (FIG. 2).
[0022]
In this way, it is possible to interlock the pair of left and right arms while avoiding interference between the members, and to secure a mounting space for the spare tire between the pair of left and right base arms (4, 8).
Note that the attachment position of the spare tire carrier 35 is not limited to the upper surface of the attachment member 33 and may be a side surface. Further, the cross-sectional shape of the mounting member 33 is not limited to the channel shape, and various hollow shapes are possible. However, the portion in contact with the spare tire 37 is preferably a flat surface from the viewpoint of stable maintenance.
[0023]
A series of normal operations (lifting and lowering and storing) in the load receiving table lifting / lowering device 1 configured as described above will be described.
First, after stopping the vehicle and pulling the parking brake, the hydraulic cylinder 30 (FIG. 4) is driven from the state shown in FIG. 2 to rotate the base upper arm 8 and the base lower arm 4 clockwise to the lower end. Let As a result, the load receiving base 18 is pushed away by the guide roller 23, and the distal end lower arm 13 and the distal end upper arm 16 are slightly opened clockwise around the pins 6 and 10, respectively, as shown in FIG. To.
[0024]
Next, the operator pulls the folded cargo receiving tray 18 backward by hand. As a result, the distal end lower arm 13 and the distal end upper arm 16 rotate in the clockwise direction around the pin 6 and the pin 10, respectively. During this rotation, the parallelogram CDEF formed by the pins 10, 6, 17 and 14 changes its shape, but the side CD and the side EF maintain a parallel relationship with each other. Accordingly, the load receiving platform 18 descends while maintaining a certain posture, and reaches near the floor as shown in FIG. Thereafter, the operator raises and rotates the sub-plate 20 of the load receiving table 18 by hand, and unfolds as shown in FIG.
[0025]
When unloading a load, the hydraulic cylinder 30 (FIG. 4) is driven to rotate the base upper arm 8 and the base lower arm 4 counterclockwise. In accordance with this, the tip end upper arm 16 and the tip end lower arm 13 also rotate, and the load receiving stand 18 rises. At this time, the pair of left and right base upper arms 8 are interlocked with each other due to the presence of the connecting member 32. Similarly, each arm (4, 13, 16) that rotates according to the base upper arm 8 also rotates in conjunction with each other in a pair of left and right. During this ascent, the side CD of the base link mechanism (ABCD) is gradually tilted with respect to the side AB, so that the side EF of the tip end link mechanism (CDEF) is similarly tilted. Gradually level from the state. In this way, the load receiving stand 18 rises to the rising end indicated by the two-dot chain line in FIG. 5 where the load receiving stand 18 and the floor surface of the load box 102 coincide. Here, the operator transfers the load from the load box 102 to the load receiving platform 18. After the transfer, the hydraulic cylinder 30 (FIG. 4) is driven to rotate the base upper arm 8 and the base lower arm 4 in the clockwise direction. In accordance with this, the distal end upper arm 16 and the distal end lower arm 13 are also rotated, and the load receiving table 18 is lowered. During the lowering, the side CD of the base link mechanism is gradually tilted with respect to the side AB, so that the side EF is similarly tilted, and the load receiving platform 18 is gradually shifted from the substantially horizontal state to the tilted state. Reach the falling edge. Accordingly, no impact is applied to the load, and the load can be prevented from falling or falling.
When loading a package into the packing box 102, the above operations are performed in the reverse order.
[0026]
Next, when storing the load receiving platform lifting / lowering device 1, the operator folds the sub-plate 20 from the state shown by the solid line in FIG. 5, and then lifts the folded load receiving stand 18. Return to the state shown in FIG. Here, the hydraulic cylinder 30 (FIG. 4) is driven to rotate the base upper arm 8 and the base lower arm 4 in the counterclockwise direction. Thereby, the cargo receiving stand 18 is in the state shown in FIG. 2 and is stored in the lower part of the vehicle body 101.
[0027]
In the above-described embodiment, the rotation shafts of the pair of left and right base upper arms 8 are connected. However, if necessary, the rotation shafts of the pair of left and right base lower arms 4 are connected instead. It is also possible to do.
In the above embodiment, the hydraulic cylinder 30 (FIG. 9) is attached to the support member 2B, that is, the vehicle body side, and the piston is connected to the base upper arm 8 side. The side may be attached to the base upper arm 8 or the like, and the piston may be connected to the vehicle body side.
Further, in the above-described embodiment, the load receiving platform lifting / lowering device 1 has been described as being pulled out rearward of the vehicle body 101. However, the configuration can be similarly applied to a configuration that is pulled out to the side.
[0028]
【The invention's effect】
According to the load receiving platform lifting / lowering device of the present invention configured as described above, since the connecting member that integrally forms the pivot shaft with the base arm is provided, the pair of left and right base arms can be interlocked with each other. Further, since the connecting member is present at the rotation axis position of the base arm, it is possible to avoid interference between the connecting member, the base arm, and the tip arm when the load receiving table is stored. Further, since the mounting member for passing the connecting member is provided between the pair of left and right support members of the load receiving platform lifting device and the spare tire carrier is provided in the middle in the vehicle width direction , the spare tire is provided between the pair of left and right base arms. A mounting space can be secured. Also, since the spare tire is held by being pressed against the lower end surface of the mounting member by a chain suspended through the opening of the mounting member having a channel-shaped cross section, the spare tire is held directly on the mounting member. can do.
[Brief description of the drawings]
FIG. 1 is a rear view of a state in which a cargo receiving platform lifting device including an arm structure according to an embodiment of the present invention is attached to a lower part of a cargo box at a rear part of a vehicle body of a truck.
FIG. 2 is a side view of the load receiving table lifting device, showing a state of being stored in a vehicle body.
FIG. 3 is a side view of the load receiving table lifting device, showing a state during expansion or storage.
FIG. 4 is a side view of the load receiving table lifting device, showing a state in which the distal end link mechanism is expanded with respect to the base link mechanism and the load receiving table is folded.
FIG. 5 is a side view of the load receiving table lifting device, showing a state in which the tip link mechanism and the load receiving platform are deployed and moved up and down.
FIG. 6 is a side view showing in principle a load receiving platform in the load receiving platform elevating device and an arm structure including a base link mechanism and a tip link mechanism for moving the load receiving platform up and down.
FIG. 7 is a diagram showing how a size relationship between sides AB and CD in a link mechanism having an unequal side rectangle generally affects a link operation;
8 is an exploded perspective view of the arm structure (example on the left side when viewed from the rear of the vehicle body) shown in FIGS.
FIG. 9 is a plan view (including a sectional view partially broken horizontally) showing a detailed structure between a pair of left and right support members of a vehicle body and a mounting position of a spare tire.
10 is a view corresponding to a cross section taken along line XX in FIG. 9;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cargo stand raising / lowering device 2B Support member 4 Base lower arm 8 Base upper arm 9 Arm shaft member 13 Tip lower arm 16 Tip upper arm 18 Cargo cradle 30 Hydraulic cylinder 32 Connecting member 33 Mounting member 35 Spare tire carrier 37 Spare tire

Claims (1)

In the load receiving platform lifting device capable of lifting and lowering and storing / deploying the load receiving platform by turning the base arm and the distal end arm provided on the left and right of the vehicle body
A pair of left and right support members for attaching the load receiving platform lifting device to the vehicle body side;
A pair of cylinders for respectively driving the pair of base arms;
Have a cross section of the channel-shaped, in a state in which the opening to the bottom, and the member Mounting provided in the vehicle width direction between the pair of support members,
A spare tire carrier that holds the spare tire by pressing it against the lower end surface of the mounting member by means of a chain that is mounted in the middle of the mounting member in the vehicle width direction and is suspended through the opening ,
And a connecting member that is disposed through the mounting member, connects the pivot shafts of the pair of base arms to each other, and integrally forms the pivot shaft with the pair of base arms. Cargo stand lifting device.

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