JPH0664757A - Loading/unloading device for truck - Google Patents

Abstract

PURPOSE:To prevent collapse of a load during its transportation while facilitating loading/unloading by providing a load transfer unit and a supporting frame transfer unit on a load carrying platform floor surface of a truck, so that the load can be transferred to the front and rear. CONSTITUTION:In a loading/unloading device for a truck, a plurality of sets of chains 5 are endlessly annularly wound along a longitudinal direction in a vehicle load carrying platform 1, to fix a load carrying platform building material 7 of constituting a slip stop moving load carrying platform in a juxtaposed condition to the chain 5, to also provide a front part load supporting plate 8, moved integrally with the chain 5, to vertically rise in the forefront part of the load carrying platform building material 7, and by driving the chain 5 forwardly/reversely rotated, a load can be moved before and after a vehicle by the front part load supporting plate 8 and the load carrying platform building material 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a lorry, and in particular to
The present invention relates to a loading / unloading device for a box type lorry.

2. Description of the Related Art The prior art is, for example, Jitsuko Sho 52-3.
As described in Japanese Patent No. 7055, a luggage transfer device including a roller conveyor and a belt conveyor is provided on the floor surface of a bed of a box-type freight vehicle so that the luggage placed on the cargo transportation device can be transported back and forth. In order to load the movable support frame by moving it forward and backward by the support frame transfer device provided at the upper and lower corners of the box so that it can be fixed at an appropriate position, open the door at the rear of the box and place the movable support frame near the door. After stopping the movement to an appropriate position, contacting the rear surface of the moving support frame and loading an arbitrary amount on the luggage transfer device, press the moving support frame forward together with the luggage, repeat the loading work, and complete. Then, the moving support frame is fixed with a fixing device to support the luggage between the door and the moving support frame to prevent the cargo from collapsing and to be transported. , Fixing the moving support frame by the fixing device The solved, and performs unloading and transferring the upper cargo transferring device to sequentially door opening of cargo.

[0002]

In the prior art, since the luggage transfer device and the moving support frame transfer device are provided separately, it is difficult to move, stop, and fix the two devices at the same time. . When the load moves freely like the roller conveyor of the luggage transfer device described in the above publication, all impacts such as sudden braking during traveling are applied to the moving support frame, and it is necessary to strengthen the moving support frame. At the same time, a considerably strong fixing device is required for the transfer device, and in the case of unloading, it is necessary to transfer the load by pushing it with the moving support frame. In addition, there is a problem that there is no countermeasure against rolling of the automobile.

[0003]

SUMMARY OF THE INVENTION Therefore, according to the present invention, sprocket shafts having sprockets arranged at predetermined intervals are provided at front and rear portions of a vehicle bed so as to face each other, and the sprocket shafts are arranged along the front-rear direction of the vehicle. A plurality of chains are wound in an endless ring, and the upper side of the chain is formed by a chain with a mounting portion, and the loading platform assembly constituting the non-slip movable loading platform is juxtaposed to the mounting portion in the direction orthogonal to the moving direction of the chain. The front luggage support plate which is fixed in a state of being fixed, and further provided at the forefront of the luggage carrier member so as to move integrally with the chain in an upright manner, and the sprocket shaft is driven to rotate forward and backward to drive the front luggage carrier plate and the luggage carrier assembly. An object of the present invention is to provide a loading / unloading device for a freight vehicle, in which materials are movably provided in front of and behind the vehicle. Further, the present invention provides the above-mentioned loading / unloading device for a freight vehicle, wherein a speed reducer is provided between the sprocket shaft and a motor shaft that drives the shaft in forward and reverse rotations, and the speed reducer is used as a chain stop device. (EN) A loading / unloading device for a lorry, which is also used.

Further, the present invention provides the loading and unloading device for a freight vehicle, wherein a guide support member is provided on a side portion of the luggage carrier assembly along the moving direction of the chain with the attachment portion, and the front luggage is provided. Provided is a loading / unloading device for a freight vehicle, characterized in that an upright holding member integrally provided on a base portion of a support plate along a moving direction of a chain is movably engaged with the guide supporting member. It is what Further, the present invention, in the loading and unloading device of the above-mentioned freight vehicle, while supporting the chain with an attachment portion by a vertically long support square member provided along a moving direction,
The supporting square members are supported by horizontal base members arranged at predetermined intervals in the left-right lateral direction, and between adjacent horizontal base members, the front part of the vehicle is supported at a wide interval and the rear part of the vehicle is supported at a narrow interval. The present invention provides a loading / unloading device for a freight vehicle. Further, the present invention is characterized in that, in the above-mentioned loading and unloading device for a lorry, a chain adjusting device is provided adjacent to each sprocket between a sprocket shaft and a horizontal base material parallel to the sprocket shaft. An unloading device for a lorry is provided. Further, the present invention is
A loading / unloading device for a lorry, characterized in that a lateral luggage support plate is provided so as to be movable laterally along the longitudinal direction of the luggage carrier assembly. It is a thing.

[0005]

According to the loading and unloading device for a freight vehicle according to the present invention, the front luggage support plate and the luggage carrier are moved forward and backward by driving the sprocket shaft to rotate forward and backward to move the chain forward and backward. Since it is possible to move at the same time, to load, open the door of the bed and rotate the sprocket shaft to move the front luggage support plate to an appropriate position,
After contacting the rear surface of the front luggage support plate and loading an arbitrary amount on the luggage carrier assembly, rotate the sprocket shaft to move the load to an appropriate position integrally with the front luggage support board and the luggage carrier assembly. Can be moved and repeatedly loaded. At this time, since the load is placed on the carrier assembly that constitutes the non-slip movable carrier that is fixed in a juxtaposed state in the direction orthogonal to the direction of movement of the chain, when carrying it after completing the loading,
The front luggage support plate effectively prevents the vehicle from falling down without sliding on the luggage carrier assembly due to the vibration of the automobile or the impact of sudden braking. Next, when unloading, the sprocket shaft is driven in reverse to reversely move the load together with the front luggage support plate and the carrier assembly to the door, and then unload it. It can be carried out.

Further, in the above-mentioned loading and unloading device for a freight vehicle, a reduction gear is provided between the sprocket shaft and a motor shaft for driving the shaft in forward and reverse rotations, and the reduction gear is also used as a chain stopping device. According to the loading and unloading device for a freight vehicle according to the present invention, which is characterized by being able to slowly and smoothly move the chain that carries a heavy load by the reduction gear, stop the power supply to the motor and stop the motor. When this happens, all of the sprocket shaft, chain, front luggage support plate, cargo bed assembly and cargo will be stopped via the reduction gear. Even if the chain tries to move due to the load on the luggage support plate or the sprocket shaft is rotated, the speed reducer provided between the sprocket shaft and the motor shaft will Of reducing its rotational force to the extent not exceeding stopping force, and thus to keep the front cargo support plate and the bed assembly member in a fixed state by the stopping power of the motor.

Further, in the above-mentioned loading / unloading device for a freight vehicle, a guide support member is provided on a side portion of the luggage carrier assembly along the moving direction of the chain with the attachment portion, and a base portion of the front luggage support plate is provided. In the loading / unloading device for a freight vehicle according to the present invention, an upright holding member integrally provided in the rear longitudinal direction along the moving direction of the chain is engaged movably along the guide supporting member. According to
A load can be easily applied to the front luggage support plate that prevents the load from tipping over due to the impact of sudden braking during transportation, etc., and it can be easily countered by the upright holding member that is integrally provided at the base of the front luggage support plate. The upright holding member that is integrally provided in the rear longitudinal direction along the direction can also function as a stopper when moving backward. Further, in the above-mentioned apparatus for loading and unloading a freight vehicle, the chain with the attachment portion is supported by a vertically long supporting square bar provided along the moving direction, and the supporting square bar is laterally arranged at predetermined intervals in the lateral direction. According to the loading and unloading device for a lorry of the present invention, which is supported by a base material, and between adjacent horizontal base materials, a vehicle front part is supported at a wide interval, and a vehicle rear part is supported at a narrow interval. Since multiple sets of chains that support the loading platform are firmly supported by the vertically-supporting square bars, and the lower part is supported by the horizontal foundation material, it is possible to strongly support the load on the loading platform. On the other hand, since the vehicle's rear part, which is particularly weighted during loading, is provided with horizontal base materials at narrow intervals,
It can strongly resist the impact of loading. Further, in the above-mentioned loading / unloading device for a lorry, according to the device in which a chain adjusting device is provided adjacent to each sprocket between the sprocket shaft and a horizontal base material parallel to the sprocket shaft, a plurality of sets of normal It is possible to individually adjust the tension of each of the chains that are driven to rotate in reverse, so that the chains can be uniformly operated and driven. Further, in the unloading device for a lorry, the unloading device for a lorry of the present invention is characterized in that a lateral luggage support plate is provided so as to be movable laterally along the longitudinal direction of the luggage carrier assembly. According to the device, the lateral load supporting plate supports the load even when it rolls during transportation, and thus it is possible to prevent the load from falling and falling.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The loading and unloading device for a freight vehicle according to the present invention will be described in detail with reference to the embodiments shown below.
Is a vehicle carrier of a box-type freight vehicle, and sprocket shafts 3 and 4 having sprocket 2 arranged at predetermined intervals are provided opposite to each other at a front portion and a rear portion thereof. Between the opposing sprockets 2, a plurality of sets of chains 5 are arranged along the longitudinal direction of the vehicle.
Is wound in an endless ring, and the upper side of the chain is constituted by a chain 6 with a mounting portion, and the loading platform assembly 7 constituting a non-slip movable loading platform is fixed to the mounting portion in a juxtaposed state in a direction orthogonal to the moving direction of the chain. I am doing it. The cargo carrier assembly 7 is fixed only in a juxtaposed state in a direction orthogonal to the moving direction of the chain, and has an effect of preventing the slip of the cargo against an impact in the front-rear direction of the vehicle. It is preferable to provide anti-slip means on the front, back, left and right by applying anti-slip made of synthetic resin or grooves in 45 ° direction, unevenness, and the like. 25 is a front wall of the vehicle body. A front luggage support plate 8 that moves integrally with the chain is provided upright on the forefront of the luggage carrier 7. Reference numeral 9 denotes a motor for driving the sprocket shaft 3 in forward and reverse directions. The front load supporting plate 8 and the luggage carrier 7 are driven by driving the sprocket shaft 3 in forward and reverse directions through a speed reducer 10 having a high reduction ratio. It is provided to be movable before and after. Reference numeral 11 denotes a skeleton member provided on the left and right sides and the center portion along the moving direction of the chain for installing the device of the present invention on the carrier 1, and includes the bearing portions 12 of the sprocket shafts 3 and 4. The rear bearing portion 12 is attached to the frame member 11 so as to be movable and adjustable by a tension adjusting member 13 of the chain. In the case of the embodiment, as shown in FIG. 2, each sprocket 2 is fixed to the sprocket shafts 3 and 4 so as not to move in the axial direction by the reinforcing collars 2a provided on both sides thereof.

Reference numeral 14 is a vertically long supporting square member provided along the moving direction of the chain 6 with the attaching portion, and firmly supports the lower side of the chain 6 with the attaching portion. Also, 15
Is a horizontal foundation member which is arranged on the skeleton member 11 in the left-right lateral direction at predetermined intervals to support the supporting square members 14. Adjacent horizontal base materials 15 are arranged at wide intervals in the front part of the vehicle and at narrow intervals in the rear part of the vehicle, and the horizontal base members are provided at narrow intervals in the rear part of the vehicle where impact loading is particularly likely to occur during loading. 1
With 5 it is possible to compete strongly and durability is improved. In addition, a plurality of reinforcing members 15 are provided between the horizontal foundation members 15 near the loading port.
a is provided in the vertical direction, and individual chains 5, 6 are provided between the sprocket shaft 4 and the adjacent horizontal base material 15.
A chain adjusting device 30 is provided which maintains the tension of each of the chains evenly, prevents the chain from loosening, and prevents frame jumps and lateral shifts of the sprockets. In the case of the embodiment, the chain adjusting device 30 is provided between the two chains one by one, and is individually adjustable. In the embodiment of the chain adjusting device 30, as shown in FIGS. 5 to 7, the advancing / retreating screw shaft 32 having a bearing portion 31 for rotatably bearing-supporting the sprocket shaft 4 at its tip has a horizontal foundation member 15. The casing 33 is fixed to the casing 33 so that it can move back and forth without rotating. Inside the casing 33, a worm internal screw gear 34a that is screwed onto the outer circumference of the advancing / retreating screw shaft 32 and moves the shaft 32 advancing / retreating with its rotation.
The worm wheel 34 integrally having the wheel retainer 35,
It is rotatably provided between 36. A worm gear 34b is provided on the outer circumference of the worm wheel 34, and a worm screw 37 rotatably provided on the casing 33 is provided on the outer circumference thereof.
Are screwed together. The casing 33 for the worm screw 37
Is provided with an operation angle shaft 38 protruding outside, and when the operation angle shaft 38 is operated to rotate in the forward and reverse directions, the worm wheel 34 rotates, and the screw shaft 32 moves forward and backward with the rotation.
By adjusting the position of the sprocket shaft 4 with respect to the horizontal base material 15, the tension of each chain 5 and 6 is maintained evenly, the looseness of the chain is prevented, and the frame jump and the lateral displacement of the sprocket 2 are prevented. can do.

The speed reducer 10 may be constituted by a gear train or the like, but in the case of the embodiment, it comprises a multi-row timing belt provided between the shaft of the motor 9 and the sprocket shaft 3 for transportation. Even if the chains 5 and 6 try to move and rotate the sprocket shaft 3 due to the load of the load on the front luggage support plate 8 due to an impact such as sudden braking, the stop force of the motor 9 is stopped by the reduction gear 10. The torque is reduced to the extent that it does not exceed
It is configured such that the front load supporting plate 8 and the luggage carrier assembly 7 can be maintained in a fixed state by the stopping force of. Reference numeral 16 denotes a guide support member provided on a side portion of the luggage carrier assembly 7 along the movement direction of the chain 6 with the attachment portion, and a guide movement member at the base portion of the front luggage support plate 8 in the movement direction of the chain. Upright holding member 17 integrally provided in the rear longitudinal direction along the
Is movably engaged. In the case of the embodiment, the guide support plate 16 is, as shown in FIG.
1, which is integrally provided on the outside of the upright holding member 17
Is provided with a plurality of rollers 18 along the rear longitudinal direction along the moving direction of the chain, and the rollers 18 roll so as to sandwich the upper and lower surfaces of the guide support plate 16 to thereby provide a front load. The support plate 8 is constructed so as to maintain the upright state. Further, the upright holding member integrally provided in the rear longitudinal direction along the moving direction of the chain is configured so as to contact a limit switch for stopping the motor provided on the rear side of the skeleton member 11, so that the stopper at the time of rearward movement. Can also have the role of. Reference numeral 19 is a reinforcing member provided between the upright holding member 17 and the front luggage support plate 8.

In FIG. 4, reference numeral 20 denotes a lateral load supporting plate provided on a horizontal frame member 21 fixed to the left and right side walls of the vehicle body so as to be movable laterally through an expansion / contraction device 22, and the front load supporting plate is the front load supporting plate. 8 and the luggage carrier assembly 7 are provided laterally so as to be movable and are located above the luggage carrier assembly 7. In the case of the embodiment, the expansion / contraction device 22 is a link 2 that expands / contracts laterally along the longitudinal direction of the luggage carrier assembly 7.
4 and air cylinders 23, which are arranged at a plurality of positions along the front-back direction of the vehicle body. Lateral luggage support plate 20
Is provided to each of the expansion / contraction devices 22 so as to be expandable / contractible individually in the lateral direction along the longitudinal direction of the luggage carrier assembly 7, and the lateral luggage support plate 20 is selectively operated according to the amount of the cargo. , It is configured to support the load and prevent lateral overturn and collapse of the load.

[0012]

According to the loading / unloading device for a freight vehicle according to the present invention having the above-described structure, sprocket shafts having sprockets arranged at predetermined intervals are provided at the front and the rear of the vehicle carrier so as to be opposed to each other. A plurality of chains are wound endlessly in the front-rear direction of the vehicle in between, the upper side of the chain is configured with a chain with a mounting portion, and the loading platform member constituting the non-slip movable loading platform is attached to the mounting portion. The front luggage support plate, which is fixed in a juxtaposed state in the direction orthogonal to the moving direction and moves integrally with the chain, is provided upright at the forefront portion of the luggage carrier assembly, and the sprocket shaft is rotated forward and backward to drive it forward. By having a structure in which a luggage support plate and a luggage carrier assembly are provided so as to be movable in the front and rear of the vehicle, the sprocket shaft is driven to rotate in the forward and reverse directions to move the chain in the forward and backward directions. Since the support plate and the luggage carrier can be moved to the front and rear of the vehicle at the same time, the load can be moved to an appropriate position integrally with the front luggage support plate and the luggage carrier to facilitate repeated loading or unloading work. In addition to the effect that it can be carried out smoothly, at this time, since the load is placed on the load carrier member that constitutes the non-slip movable load carrier that is fixed in a juxtaposed state in the direction orthogonal to the moving direction of the chain, Upon completion of stacking and transportation, there is an effect that the front luggage supporting plate effectively prevents the vehicle from falling down without sliding on the luggage carrier due to the impact of vibrations and sudden braking of the automobile.

Further, in the above-mentioned loading and unloading device for a freight vehicle, a reduction gear is provided between the sprocket shaft and a motor shaft for driving the shaft in forward and reverse rotations, and the reduction gear is also used as a chain stopping device. According to the configuration of the device of the present invention, which is characterized in that it has the effect of slowly and smoothly moving the chain that bears a heavy load by the reduction gear, and when stopping the motor by cutting off the power supply to the motor, All of the sprocket shaft, chain, front luggage support plate, luggage carrier and cargo will be stopped via the reduction gear, but during transportation etc. due to impact such as sudden braking,
Even if you try to rotate the sprocket shaft by moving the chain due to the load on the front luggage support plate of the load,
The speed reducer provided between the sprocket shaft and the motor shaft reduces the rotational force of the motor to the extent that it does not exceed the stopping force of the motor. There is an effect that the luggage support plate and the luggage carrier assembly can be maintained in a fixed state. Further, in the above-mentioned loading and unloading device for a lorry, a guide support member is provided on a side portion of a luggage carrier assembly along a moving direction of the chain with an attachment portion, and a chain of a chain is provided at a base portion of the front luggage support plate. According to the loading and unloading device for a freight vehicle of the present invention, wherein the upright holding member integrally provided in the rear longitudinal direction along the moving direction is engaged movably along the guide supporting member, A load can be easily applied to the front luggage support plate that prevents the load from tipping over due to the impact of sudden braking during transportation, etc., and it can be easily countered by the upright holding member that is integrally provided at the base of the front luggage support plate. The upright holding member provided integrally in the longitudinal direction along the rear has an effect that it can also serve as a stopper when moving backward.

In the loading / unloading device for a freight vehicle, the chain with the attachment portion is supported by a vertically long supporting square bar provided along the moving direction, and the supporting square bar is laterally spaced at predetermined intervals. A loading and unloading device for a freight vehicle according to the present invention, which is characterized in that it is supported by arranged horizontal foundation members, and between adjacent horizontal foundation members is supported by a wide space in a vehicle front part and a narrow space in a vehicle rear part. According to this, since a plurality of sets of chains supporting the loading platform member are firmly supported by the vertically long supporting square members, and the lower part is supported by the horizontal foundation member, the load is strongly supported on the loading platform member. On the other hand, since the transverse base members are provided at narrow intervals in the vehicle rear part to which a load is applied particularly when loading, there is an effect that the impact during loading can be strongly counteracted. Further, in the above-mentioned loading and unloading device for a lorry, according to a device in which a chain adjusting device is provided adjacent to each sprocket between a sprocket shaft and a horizontal base material parallel thereto.
The tension of each chain can be adjusted individually for each chain to drive multiple sets of forward and reverse rotations, and each chain can be operated and driven evenly, preventing side slippage and frame skipping due to looseness of the chain. However, there is an effect that the load can be moved evenly. Further, in the unloading device for a lorry, the unloading device for a lorry of the present invention is characterized in that a lateral luggage support plate is provided so as to be movable laterally along the longitudinal direction of the luggage carrier assembly. According to the device, the lateral load supporting plate supports the load even when it rolls during transportation, and thus there is an effect that it is possible to prevent falling and collapse of the load.

[Brief description of drawings]

FIG. 1 is a schematic side view schematically showing an embodiment of an apparatus for loading and unloading a freight vehicle according to the present invention with a part of the main part omitted.

FIG. 2 is a schematic plan view schematically showing a unloading device for a freight vehicle according to an embodiment of the present invention with a part of an essential part omitted.

FIG. 3 is a schematic front view schematically showing a unloading device for a freight vehicle according to an embodiment of the present invention with a part of an essential part schematically omitted.

FIG. 4 is a schematic plan view schematically showing a unloading device for a freight vehicle according to another embodiment of the present invention with a part of the main part omitted.

FIG. 5 is a schematic front view schematically showing a chain adjusting device according to an embodiment of the present invention with a part of the essential parts omitted.

6 is a schematic plan view schematically showing the chain adjusting device of FIG. 5 according to the present invention with a part of the essential parts omitted.

FIG. 7 is a schematic side view schematically showing the chain adjusting device of FIG. 5 according to the present invention with a part of the essential parts omitted.

[Explanation of Codes] 1 ... Cargo carrier 2 ... Sprocket 3 ... Sprocket shaft 4 ... Sprocket shaft 5 ... Chain 6 ... Chain with mounting section 7 ... Cargo carrier assembly 8 ...・ Front luggage support plate 9 ・ ・ ・ Motor 10 ・ ・ Reduction device 11 ・ ・ Frame member 12 ・ ・ Bearing part 13 ・ ・ Tension adjusting member 14 ・ ・ Supporting square member 15 ・ ・ Horizontal foundation member 16 ・ ・ Guide support member 17・ ・ Standing member 18 ・ ・ Roller 19 ・ ・ Reinforcement member 20 ・ ・ Lateral luggage support plate 21 ・ ・ Horizontal frame member 22 ・ ・ Expansion device 23 ・ ・ Air cylinder 24 ・ ・ Link 25 ・ ・ Front wall 30 ・ ・Chain adjusting device 31..Bearing part 32..Advancing and retracting screw shaft 33..Casing 34..Warm wheel 35..Wheel presser 36..Wheel presser 37..Worm screw 38 ..

Claims (6)

[Claims] 1. A sprocket shaft having sprockets arranged at predetermined intervals at front and rear portions of a vehicle carrier is opposed to each other, and a plurality of sets of chains are wound endlessly in an anteroposterior direction of the vehicle between the opposing sprockets. The upper side of the chain is constituted by a chain with a mounting portion, and the mounting portion which constitutes the non-slip movable carrier is fixed to the mounting portion in a juxtaposed state in a direction orthogonal to the moving direction of the chain. A front luggage support plate that moves integrally with the chain is provided upright at the frontmost portion, and the front luggage support plate and the luggage carrier assembly are movably provided in the front and rear of the vehicle by driving the sprocket shaft to rotate forward and backward. Loading and unloading equipment for lorries 2. The loading / unloading device for a freight vehicle according to claim 1, wherein a speed reducer is provided between the sprocket shaft and a motor shaft that drives the shaft to rotate in the forward and reverse directions, and the speed reducer is connected to a chain. Loading and unloading device for lorries, which is also used as a stop device 3. The loading / unloading device for a freight vehicle according to claim 1 or 2, wherein a guide support member is provided on a side portion of the luggage carrier assembly along a moving direction of the chain with the attachment portion, and the front portion is provided. A cargo of a freight vehicle characterized in that an upright holding member integrally provided on a base portion of a luggage supporting plate in a rear longitudinal direction along a moving direction of a chain is movably engaged with the guide supporting member. Unloading device 4. The loading / unloading device for a freight vehicle according to claim 1, 2 or 3, wherein the chain with the attachment portion is supported by a vertically long support square bar provided along a moving direction, and the support square bar is also provided. Is supported by horizontal foundation members arranged at predetermined intervals in the lateral direction, and between adjacent horizontal foundation members, a front portion of the vehicle is supported at a wide interval and a rear portion of the vehicle is supported at a narrow interval. Loading and unloading equipment 5. The loading / unloading device for a freight vehicle according to claim 1, 2, 3 or 4, wherein a chain adjustment is provided adjacent to each sprocket between a sprocket shaft and a horizontal base member parallel thereto. Equipment for loading and unloading lorries, characterized by having a device 6. The method according to claim 1, 2, 3, 4 or 5.
The unloading device for a lorry according to claim 1, wherein a lateral luggage support plate is provided so as to be movable laterally along the longitudinal direction of the luggage carrier.