JP2004249809A - Carrying vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To connect divided bumpers to each other without a height difference. <P>SOLUTION: At the connection end of side bumpers 21 and 22, an inner wall 28 is erected and an insert groove 30 is formed in the clearance thereof from a side wall 25. In the insert groove 30, an insert piece 36 projectedly formed at the connection end of a corner bumper 23 is inserted into the insert groove 30 for connection. At an insert part 37 inserted into the groove bottom side of the insert groove 30, the projected end side thereof is formed in a converged tapered part 40 at the inner end edge thereof, and the bottom side thereof is formed in a fitting part 41 tightly fitted between a side wall 25 and an inner wall 28. Since the fitting part 41 of an insert piece 36 with rather high rigidity is formed to fit tightly to the groove bottom side of the insert groove 30, the fitting part is not kept in a deformed state due to the absence of room to allow to open to the outside even on the upper end sides of unscrewed upper wall 27 and side wall 25. As a result, the height difference is prevented from occurring at a joint portion between the side wall 25 and upper wall 27 and a corner bumper 23 at the connection end of the side bumpers 21 and 22. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a transportation vehicle, and more particularly to an improvement in a structure for mounting a bumper provided around a main body.
[0002]
[Prior art]
As an example of this type of transport vehicle, there is a hot and cold serving truck used in hospitals and the like, and in such a serving truck, the main body is not damaged even if it accidentally hits a wall or the like while moving. A bumper is provided on the outer periphery of the bottom or ceiling of the main body (for example, see Patent Document 1).
The details of the arrangement structure of the bumper of Patent Document 1 will be described below by taking a lower bumper as an example. As shown in FIGS. 18 to 20, the lower bumper is formed in a substantially channel shape by a synthetic resin material, is mounted with the opening side facing down, and is disposed along the side surface of the main body. Side bumper 1 and a corner bumper 2 disposed at a corner of the main body.
At the connection end of the side bumper 1, an insertion groove 5 is formed between the side wall 3 </ b> A and the inner wall 4, which extends downward from the upper wall 3 </ b> B. A piece 6 is protruded, and the connection ends of the corner bumper 2 and the side bumper 1 are abutted against each other while the insertion piece 6 is inserted into the insertion groove 5 so as to be connected.
[0003]
[Patent Document 1]
JP 2000-168570 A
[Problems to be solved by the invention]
Incidentally, since the side bumper 1 is formed in a relatively thin and long shape by extrusion molding, the side bumper 1 tends to be twisted and easily deformed when opened or closed. Therefore, the distortion is corrected by fitting a metal reinforcing plate at an intermediate position in the length direction, but the reinforcing plate cannot be used at the connection end side with the corner bumper 2 because the insertion piece 6 is inserted.
However, even at the connection end side, the lower wall 3C can be fixed to the mounting plate 7 fixed to the inner surface of the corner bumper 2 with screws 8 as shown in FIG. Then, it cannot be screwed down because of the appearance. On the other hand, between the insertion piece 6 of the corner bumper 2 and the insertion groove 5 of the counterpart, as shown in FIG. 19, a certain gap s is set so that insertion can be performed smoothly. Therefore, when the connection end side of the side bumper 1 is distorted, the side wall 3A and the upper wall 3B that cannot be screwed open outward as shown by a chain line in FIG. As a result.
[0005]
Then, a step is formed in the joint portion t (FIG. 20) between the side wall 3A and the upper wall 3B with the corner panel 2, and there is a problem that the appearance is deteriorated. Therefore, when trying to correct the step, it is necessary to reassemble parts around the bracket and the like, and there is a problem that it takes time and effort.
The present invention has been completed based on the above circumstances, and an object of the present invention is to enable divided bumpers to be connected to each other without a step.
[0006]
[Means for Solving the Problems]
As means for achieving the above object, the carrier according to the invention of claim 1 is provided with a hollow bumper around a main body having wheels on a bottom surface, and the bumper extends along a side surface of the main body. And a corner bumper arranged at a corner of the main body, and an inner wall is provided at one of the connection ends of the side bumper and the corner bumper to be inserted between the side bumper and the outer wall. A groove is formed, and an insertion piece projects from the other connection end, and the two pieces of bumpers are connected by inserting this insertion piece into the insertion groove. The insertion piece is characterized in that a base side can be tightly fitted into the insertion groove, and a tip side is tapered.
The invention according to claim 2 is the bumper according to claim 1, wherein the insertion piece can be inserted into a groove bottom side of the insertion groove, while the bumper on which the insertion piece protrudes is provided. Is characterized in that a projecting piece which can be tightly inserted into the opening side of the insertion groove is protruded from the connection end of the insertion groove.
[0007]
In the truck according to the third aspect of the present invention, a hollow bumper is provided around a main body having wheels on a bottom surface, and the bumper includes a side bumper disposed along a side surface of the main body, And a corner bumper arranged at a corner. At one of the connection ends of the side bumper and the corner bumper, an insertion groove is formed between the side bumper and the outer wall by erecting an inner wall, and the other connection end is formed. Is provided with a projection, and the projection is inserted into the insertion groove so that the two bumpers are connected. The outer wall of the bumper on which the insertion groove is formed is provided. A rib is provided on the inner surface of the insertion groove at a position separated from the groove bottom of the insertion groove, while a connection end of a mating bumper is provided between the groove bottom of the insertion groove and the rib together with the insertion piece. A regulating projection that fits tightly on the The tip of the rib, characterized in was constructed locking portion for restricting the outward movement of the outer wall engages the restricting projection is provided.
[0008]
Function and effect of the present invention
<Invention of claim 1>
Since the base of the insertion piece is tightly fitted in the insertion groove, there is no room for deformation such as the opening of the outer wall of the panel near the position where the insertion groove is formed, and it is kept in a distorted state. It is prevented from being removed. For this reason, it is possible to prevent a step from being formed at a joint portion of the outer wall between the side panel and the corner panel, and it is possible to achieve a good appearance. Further, since the work for correcting the distortion is not required, the work efficiency of the assembling can be improved. On the other hand, since the front end side of the insertion piece is tapered, the first insertion of the insertion piece can be performed smoothly.
<Invention of Claim 2>
Since the protruding piece is directed to the opening side of the inner wall and is prevented from tilting, there is no room for deformation such that the wall of the outer wall on which the inner wall is erected is closed inward, that is, the distortion is corrected.
[0009]
<Invention of Claim 3>
Since the insertion piece and the regulating protrusion are tightly fitted between the groove bottom of the insertion groove and the rib, the bumper on the side where the insertion groove is formed is oriented in the direction in which the inner wall is erected. The rattling is prevented, and the distortion in the same direction is corrected. In particular, a step is prevented from being formed at the joint between the wall of the outer wall on which the inner wall is raised and the mating bumper. The locking portion at the tip of the rib is locked to the restricting projection, thereby preventing the outer wall from being distorted in the opening direction and also preventing a step from being formed at the joint.
Thus, the appearance can be improved, and the work for correcting the distortion is not required, so that the work efficiency of the assembly can be improved.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment in which the present invention is applied to a hot / cold serving car will be described with reference to the accompanying drawings.
<First embodiment>
A first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the hot / cold serving car includes a serving car main body 10 formed of a rectangular heat-insulating box having open front and rear surfaces, and a heat-insulating partition wall 11 is sandwiched in the main body 10. The two sets of the adjacent storage compartments 12 and 13 are formed in a symmetrical arrangement in the left-right direction in the figure, each of which is provided with a double door 14.
A machine room 15 is provided on the upper surface of the main body 10 by assembling a plurality of panels, and houses a heating device for heating the refrigerator compartment 12, a refrigeration device for cooling the refrigerator compartment 13, a control device, and the like. On the other hand, a moving wheel 16 is provided on the bottom surface of the main body 10, and an upper bumper 19 and a lower bumper 20 are provided around the ceiling and the bottom of the main body 10, respectively.
In the pair of the warming room 12 and the cold room 13, shelves 17 are formed in a plurality of stages, and a tray (not shown) on which hot and cold foods are separately placed and penetrates the partition wall 11. While being placed on the shelf 17, the hot food placed on one tray is stored in the warming room 12, and the cold food is stored in the cold room 13, and is stored or refrigerated.
[0011]
Subsequently, the arrangement structure of the lower bumper 20 will be described.
The lower bumper 20 is made of a synthetic resin such as polypropylene, and has a pair of first side bumpers 21 (right side in FIG. 2) disposed on front and rear side surfaces of the main body 10 and a pair of second side bumpers 21 disposed on left and right side surfaces. It is composed of a side bumper 22 (left side in the figure) and four corner bumpers 23 arranged at the corners.
The first side bumper 21 is formed by extrusion molding, and is formed in a channel shape with rounded corners as a whole. The cross-sectional shape of the first side bumper 21 is such that three upper and lower ribs 26 are formed at an interval on the inner surface of the side wall 25 as shown in FIG. From a position slightly before the center of the upper wall 27 in the protruding direction, an inner wall 28 is formed to be suspended to a position slightly above the uppermost rib 26, and between the inner wall 28 and the side wall 25. An insertion groove 30 into which an insertion piece 36 of a corner bumper 23 described later is inserted is formed.
[0012]
At the lower end of the inner wall 28, a hook portion 31 bent twice inward and upward is formed, and an abutment plate 32 projecting inward from an intermediate position is formed. Although not described in detail, the hook portion 31 and the abutment plate 32 function to lock and position the first side bumper 21 on a bracket in order to attach the first side bumper 21 to the main body 10. The lower end of the inner wall 28 and the rib 26 function as hooks and positioning when a reinforcing plate is mounted in the first side bumper 21.
Similarly, the second side bumper 22 is also formed into a channel shape with rounded corners by extrusion molding, and the upper wall 27 has a different protruding length, and the end of the abutment plate 32 has a notch. Although there are some differences, for example, the basic structure is the same as that of the first side bumper 21, including that the insertion groove 30 is formed between the inner wall 28 and the side wall 25.
[0013]
The corner bumper 23 is formed by injection molding or the like. As shown in FIG. 2, the corner bumper 23 has the same height as the first and second side bumpers 21 and 22 and two side walls 35 are arranged orthogonally. In addition, the corners are rounded. On both end surfaces of the corner bumper 23 perpendicular to each other, insertion pieces 36 are formed so as to protrude by a predetermined dimension.
As shown in FIGS. 3 and 8, the cross-sectional shape of the insertion piece 36 is formed at the end of the first and second side bumpers 21, 22 in the insertion groove 30 from the upper wall 27 to the side wall 25. A substantially L-shaped insertion portion 37 that can be inserted along the inner surface extending over the upper end portion, a relief portion 38 that is recessed inward to allow the three ribs 26 to escape, and a hook on the lowermost rib 26 And a hooking portion 39 formed in a row.
[0014]
In particular, at the inner edge of the upper side 37A of the insertion portion 37, as shown in FIG. 5 and FIG. 9, the approximately 略 length portion on the protruding end side (the lower side in FIG. 9) is directed toward the tip. The tapered portion 40 gradually becomes narrower, and the inner side thereof becomes a fitting portion 41 having a width that fits tightly in the insertion groove 30, that is, between the inner wall 28 and the side wall 25. ing. At the base end on the far side of the fitting part 41, a relief part 42 narrowing toward the far end is formed.
Note that a metal mounting plate 44 is mounted on the inner surface of the corner bumper 23. The mounting plate 44 is applied to a boss 46 having a screw hole 45 protruding from the inner surface of the corner bumper 23, and is fixed by tightening a screw 47.
[0015]
The lower bumper 20 is assembled as follows.
First, brackets (not shown) for attaching the first side bumper 21 and the second side bumper 22 are fixed to the front and rear edges and the left and right edges of the lower surface of the main body 10, respectively. The bracket 50 for fixing the corner bumper 23 is fixed.
A reinforcing plate is mounted on the first side bumper 21, and a pair of first side bumpers 21 are fixed to a bracket previously fixed to the main body 10 by fixing a mounting portion of the reinforcing plate from below with a screw. It is attached along both front and rear edges of the lower surface of the main body 10.
[0016]
Next, corner bumpers 23 are integrally attached to both ends of the second side bumper 22. Similarly, a reinforcing plate is attached to the second side bumper 22 in advance, and a mounting plate 44 is fixed to the inner surface of the corner bumper 23. As shown by the arrow A in FIG. 2, the insertion pieces 36 of the corner bumpers 23 are inserted into the insertion grooves 30 and connected to the insertion grooves 30 at both ends of the second side bumper 22, respectively. The lower wall 29 of the bumper 22 is fixed to the mounting plate 44 by screws 52.
The second side bumper 22 integrally connected to the corner bumpers 23 has the other insertion pieces 36 of the corner bumpers 23 at both ends attached first as shown by the arrow B in FIGS. 2 and 7. The lower wall 29 of the second side bumper 22 is similarly fastened to the mounting plate 44 of the corner bumper 23 by screws 52 so as to be inserted and connected to the insertion groove 30 at the corresponding end of the one side bumper 21. .
At the same time, the mounting position of the reinforcing plate on the second side bumper 22 is fixed to the bracket previously fixed to the main body 10 by screws from the lower surface side, and the pair of second side bumpers 22 It is attached along both edges, and the attachment plate 44 of the corner bumper 23 is also screwed to the bracket 50 from the lower surface side and attached to the corner portion, whereby the attachment of the lower bumper 20 is completed.
[0017]
Here, a connection structure between the side bumpers 21 and 22 and the corner bumper 23 will be described in more detail by taking the first side bumper 21 as an example. As shown by the arrow B in FIG. 7, when the insertion piece 36 is inserted into the insertion groove 30, the insertion portion 37 is formed on the inner surface of the insertion groove 30 extending from the upper wall 27 to the upper end of the side wall 25. Since the protruding end side of the upper side 37A of the insertion portion 37 is a tapered tapered portion 40, the insertion is smoothly performed by being guided by the tapered portion 40.
When the edge of the corner bumper 23 is inserted until it comes into contact with the edge of the first side bumper 21, as shown in FIGS. 8 and 9, the fitting portion 41 of the upper side 37 </ b> A of the insertion portion 37 At the bottom of the groove (the upper end in FIG. 8), the state is tightly pressed between the side wall 25 and the inner wall 28.
[0018]
That is, the fitting portion 41 of the relatively rigid insertion piece 36 protruding from the corner bumper 23 is tightly fitted to the groove bottom of the insertion groove 30 of the first side bumper 21. Even at the upper end side of the upper wall 27 and the side wall 25 that are not screwed at the connection end of the first side bumper 21, there is no room to open outward, in other words, the distortion is maintained in a corrected state.
In the connection portion between the second side bumper 22 and the corner bumper 23, the fitting portion 41 of the insertion piece 36, which is also relatively rigid, is tightly fitted to the bottom of the insertion groove 30. The upper ends of the upper wall 27 and the side wall 25 that are not screwed at the connection end of the two-side bumper 22 are prevented from opening outward.
[0019]
As described above, in this embodiment, when connecting the side bumpers 21 and 22 to the corner bumper 23, the fitting portion 41 of the relatively rigid insertion piece 36 of the corner bumper 23 is placed at the bottom of the insertion groove 30. Since the structure is such that the side wall 25 and the inner wall 28 are fitted tightly, the upper wall 27 and the upper end side of the side wall 25 that are not screwed are prevented from being left in a distorted state because there is no room to open outward. You. Therefore, a step is prevented from being formed at the joint between the side wall 25 or the upper wall 27 at the connection end of the side bumpers 21 and 22 and the corner bumper 23, and the appearance can be improved. Of course, since the work for correcting the distortion is not required, the work efficiency of the assembling can be improved.
Since the tip of the fitting portion 41 of the insertion piece 36 is a tapered portion 40 which is tapered, the initial insertion of the insertion piece 36 is performed smoothly. On the other hand, since the relief portion 42 is formed deep in the fitting portion 41, the resistance is reduced at the end of the insertion operation, and the insertion can be reliably performed to the end with the help of inertia force.
[0020]
<Second embodiment>
10 to 12 show a second embodiment of the present invention.
In the corner bumper 23A of the second embodiment, a projecting piece 55 is formed from the back side of the vertical side 37B of the insertion portion 37 of the insertion piece 36 in the first embodiment described above. The protruding piece 55 is formed at a position lower than the upper side 37A of the insertion portion 37 by a predetermined dimension and in parallel with the upper side 37A and protrudes the same length as the fitting portion 41, and the lower end of the inner wall 28 of the side bumpers 21 and 22 is formed. It is possible to abut on a position close to In addition, as shown in FIG. 11, a rounded portion 56 is provided at the tip of the protruding edge of the protruding piece 55 for guiding.
In addition, the same reference numerals are given to the portions having the same functions as those of the first embodiment, and the repeated description will be omitted.
[0021]
In the above-described first embodiment, the upper end side of the upper wall 27 or the side wall 25 of the side bumpers 21 and 22 can be opened outward by fitting the insertion piece 36 tightly into the groove bottom of the insertion groove 30. Although effectively prevented, for example, there is still a possibility that the lower end of the inner wall 28 is displaced outward (to the left in FIG. 8) and the upper wall 27 is distorted so as to close inward.
In this regard, in the second embodiment, when the insertion piece 36 is inserted into the insertion groove 30, the projecting piece 55 is directed to the lower end side of the inner wall 28 as shown in FIG. Therefore, there is no room for the upper wall 27 to close inside, that is, the distortion is corrected.
[0022]
<Third embodiment>
13 to 17 show a third embodiment of the present invention. In the third embodiment, the following improvements are added to the second embodiment.
First, on the side of the side bumpers 21B and 22B, as shown in FIG. 14, the central rib 57 of the three ribs formed on the inner surface of the side wall 25 has the same height as the upper and lower ribs 26, but is T-shaped. It is formed in a cross section.
On the other hand, as shown in FIGS. 15 and 16, a pair of upper and lower vertical projections 60 are formed at predetermined intervals on both end surfaces of the corner bumper 23 </ b> B outside the relief portion 38 of the insertion piece 36. ing.
[0023]
In other words, as shown in FIG. 17, an insertion groove 61 is formed between the upper and lower protrusions 60 so that the base portion 58 of the T-shaped rib 57 can be inserted. The insertion groove 61 is formed at the base of the T-shaped rib 57. It has a width dimension greater than the thickness of the portion 58. A protruding portion 59 at the tip of a T-shaped rib 57 can be locked on the inner surface of both projections 60, and the tip of the inner surface of the projection 60 is a C surface 62 for guiding. I have.
In particular, as shown in FIG. 17, the upper side 37 </ b> A of the insertion portion 37 of the insertion piece 36 and the lower surface of the upper protrusion 60 are formed by the groove bottom of the insertion groove 30 and the upper surface of the base 58 of the T-shaped rib 57. Are set to fit tightly. Further, the vertical side 37B of the insertion portion 37 of the insertion piece 36 and the inner surface of the projection 60 correspond to the inner surface of the side wall 25 forming the side surface of the insertion groove 30 and the overhang portion 59 of the T-shaped rib 57. It is set to fit tightly with the back surface.
In addition, portions having the same functions as those of the first or second embodiment are denoted by the same reference numerals, and redundant description is omitted.
[0024]
In the third embodiment, in addition to the second embodiment, the following operation and effect can be further obtained. First, between the groove bottom of the insertion groove 30 and the base portion 58 of the T-shaped rib 57, the insertion portion 37 of the insertion piece 36 having relatively high rigidity and the upper projection 60 are fitted tightly. In this state, the side bumpers 21B and 22B are prevented from rattling in the vertical direction, and the distortion in the same direction is corrected. In particular, the upper wall 27 of the side bumpers 21B and 22B has a step at the joint with the corner bumper 23B. What you can do is prevented.
Also, between the inner surface of the upper end portion of the side wall 25 and the back surface of the projecting portion 59 of the T-shaped rib 57, the insertion portion 37 of the insertion piece 36, which is also relatively rigid, and the projection 60 are tightly fitted. Since the upper end of the side wall 25 can be brought into close contact with the insertion portion 37 of the insertion piece 36 without being lifted, a step is formed particularly at the seam with the corner bumper 23B at the upper end side of the side wall 25 of the side bumpers 21B and 22B. Can be prevented.
[0025]
<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and furthermore, besides the following, within the scope not departing from the gist. Can be implemented with various modifications.
(1) In the third embodiment, the upper side of the insertion portion of the insertion piece may be set so as to be inserted into the insertion groove with a clearance over the entire length, and such an arrangement is also provided by the present invention. Included in the technical scope.
(2) As for the formation of the insertion groove in the side bumper, another structure may be adopted, such as forming the insertion groove between the side wall and the upper wall by raising the inner wall.
(3) In the above embodiment, the case where the present invention is applied to the lower bumper is illustrated, but the present invention can be similarly applied to the upper bumper.
(4) When the side bumper is formed with relatively higher rigidity than the corner bumper due to the material and the molding method, etc., the insertion groove is provided on the corner bumper side and the insertion piece is provided on the side bumper side. The present invention can be applied to such a case.
(5) The present invention can be widely applied not only to the case in which the bumper is provided on only one of the bottom portion and the ceiling portion of the main body, but also to not only the catering truck but also to all transport vehicles equipped with the bumper. .
[Brief description of the drawings]
FIG. 1 is a front view of a hot / cold serving car according to a first embodiment of the present invention; FIG. 2 is an exploded perspective view of a connection portion between a side bumper and a corner bumper; FIG. 3 is an exploded cross-sectional view of the corner bumper; FIG. 5 is a plan view showing the connection operation between the corner bumper and the side bumper. FIG. 8 is a sectional view showing a connection state of the corner bumper and the side bumper. FIG. 10 is an exploded cross-sectional view of a connection portion between a side bumper and a corner bumper according to a second embodiment. FIG. 11 is a partially enlarged perspective view of the corner bumper. FIG. 12 is a cross-sectional view of a connection state between the corner bumper and the side bumper. 13 is an exploded perspective view of a connection portion between the side bumper and the corner bumper according to the third embodiment; FIG. 14 is an exploded sectional view thereof; FIG. 15 is a side view of the corner bumper; FIG. 16 is a front view of the corner bumper and FIG. back FIG. 17 is a cross-sectional view of a connection state between a corner bumper and a side bumper; FIG. 18 is an exploded perspective view of a connection portion between a side bumper and a corner bumper according to a conventional example; FIG. 19 is a cross-sectional view of the connection state; Perspective view from below [Description of reference numerals]
DESCRIPTION OF SYMBOLS 10 ... Serving car main body (main body) 16 ... Wheel 20 ... Lower bumper 21 ... First side bumper 22 ... Second side bumper 23 ... Corner bumper 25 ... Side wall (outer wall) 27 ... Upper wall (outer wall) 28 ... Inner wall 30 ... Insert Groove 36 Insert piece 37 Insert part 37A Upper side (of insert part 37) 40 Tapered part 41 Fitting part 23A Corner bumper 55 Projection piece 21B First side bumper 22B Second side bumper 23B ... Corner bumper 57 ... T-shaped rib 58 ... Root part (of T-shaped rib 57) 59 ... Extended part (of locking part) 60 ... Protrusion (restricted protrusion)

Claims (3)

A hollow bumper is provided around a main body having wheels on the bottom surface, and the bumper is divided into a side bumper disposed along a side surface of the main body and a corner bumper disposed at a corner of the main body. At one connection end of the side bumper and the corner bumper, an insertion groove is formed between the outer wall by erecting an inner wall, and an insertion piece is protruded at the other connection end, In a configuration in which the two pieces of bumpers are connected by inserting the insertion piece into the insertion groove,
A transport vehicle, wherein the insertion piece has a base portion that can be tightly fitted into the insertion groove and a tip end portion that is tapered. The insertion piece can be inserted into the groove bottom side of the insertion groove, while the connection end of the bumper on the side where the insertion piece protrudes is tightly attached to the opening side of the insertion groove. The carrier according to claim 1, wherein a projecting piece that can be inserted is protruded. A hollow bumper is provided around a main body having wheels on the bottom surface, and the bumper is divided into a side bumper disposed along a side surface of the main body and a corner bumper disposed at a corner of the main body. At one connection end of the side bumper and the corner bumper, an insertion groove is formed between the outer wall by erecting an inner wall, and an insertion piece is protruded at the other connection end, In a configuration in which the two pieces of bumpers are connected by inserting the insertion piece into the insertion groove,
On the inner surface of the outer wall of the bumper on which the insertion groove is formed, a rib is provided at a position separated from the groove bottom of the insertion groove, while a connection end of the mating bumper is provided with the insertion piece, A regulating protrusion is provided which fits tightly between the groove bottom of the insertion groove and the rib, and a tip of the rib engages with the regulating protrusion and extends outward of the outer wall. A transport vehicle provided with a locking portion for restricting movement.

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