JP4336944B2 - Carriage for transportation - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transport carriage having wheels attached to positions near the bottom four corners.
[0002]
[Prior art]
For example, as shown in FIG. 1 and FIG. 2, as a transportation carriage having wheels 1 a to 1 d attached near the bottom four corners, the planar shape of the transportation carriage is a rectangle that is long in the longitudinal movement direction X, and the longitudinal movement is performed. Wheels 1a to 1d are attached to the left and right end bottoms of the front and rear side frame panels 2 and 3 in the direction X, and one of the front and rear side frame panels 2 and 3 (the side frame panel 3 in the figure) is provided only on the left and right sides. Can be folded inside the back frame panel 4, and the loading platform 5 supported by the lower sides of these three panels 2 to 4 can be removed or inside any panel (the back frame panel 4 in the figure). 2. Description of the Related Art As shown in FIG. 2, there is known a transporting carriage configured to be nestable by folding an unused carriage in an L shape in a plan view as shown in FIG.
[0003]
In the nesting conveyance cart having the above-described configuration, as shown in Patent Document 1 and FIG. 3A, the front left and right wheels 1a and 1c use fixed wheels whose directions are fixed in the longitudinal movement direction X. When the rear left and right wheels 1b and 1d are free wheels (casters) rotatable around a vertical steering axis, the front left and right wheels 1a and 1c are oriented in the direction of travel. However, it is not possible to translate the cart diagonally forward (skew), for example. As shown in FIG. 3B, when nesting is performed so that the corner portion of the second carriage C2 folded in the same manner is inserted inside the corner portion of the first carriage C1 folded in an L shape, the second carriage C2 Must change the direction of the cart by lifting the end side, it takes considerable effort.
[0004]
Therefore, as shown in FIG. 4, all the wheels 1 a to 1 d are free wheels (casters) so that the cart can be moved in parallel in an arbitrary direction so that the above nesting operation can be easily performed. However, if all the wheels 1a to 1d are free wheels as described above, the straight traveling property during the normal moving operation is remarkably deteriorated and the unstable traveling is forced, and the inertia particularly increases. The danger increases when things are transported.
[0005]
As a means for solving the above-described problems of the transport carriage having all the wheels 1a to 1d as free wheels, as described in, for example, Patent Document 2 and Patent Document 3, as a free wheel, generally, it is vertical. It was considered to use a free wheel with its steering axis tilted at the required angle. However, in the configuration described in Patent Document 2, when the carriage is viewed from the lateral side with respect to the front-rear movement direction, all the free wheels are placed in the same direction in which the respective rotation axis for steering is located forward. Therefore, when the carriage is moved forward, it is very unstable when it is moved backward, although it can ensure straightness. Therefore, although it is easy to apply to a transport cart having a hand handle only on the rear side, it is not effective for a cart in which the forward direction is not specified like the transport cart shown in FIG. In the configuration described in Patent Document 3, a free wheel is attached to a seesaw member pivotally supported by left and right lateral support shafts, and the seesaw member swings automatically according to the moving direction of the carriage. Since it is configured so that the tilt direction of the rotating shaft center for steering of the existing wheel can always be switched to a direction that improves the straightness, it is also applicable to the type of transporting carriage that can be pushed and moved in either the front-rear direction. This is not only costly because a special seesaw member is required to mount the universal wheel, but if the seesaw movement of the seesaw member is not performed smoothly due to deterioration over time, the expected effect may not be expected. Is also big.
[0006]
[Patent Document 1]
JP-A-52-19853 [Patent Document 2]
Japanese Patent Laid-Open No. 2001-1706 [Patent Document 3]
Japanese Patent Laid-Open No. 2001-130204
[Means for Solving the Problems]
An object of the present invention is to provide a transport carriage capable of solving the above-described conventional problems, and the means is shown with reference numerals of embodiments described later, and the bottom four corners are shown. It is a transport carriage with wheels 1a to 1d attached in the vicinity, and all four wheels 1a to 1d are universal wheels, and the steering rotation axis SC of each of the universal wheels 1a to 1d is attached to the carriage. When viewed from the lateral direction Y with respect to the determined longitudinal movement direction X, the steering rotational axes SC of the front and rear universal wheels 1a, 1b (1c, 1d) are respectively inclined so as to form a reverse C shape. It is the composition which was made.
[0008]
The present invention having the above-described configuration is particularly suitable for a trolley that can be nested as described below. That is, the plane shape of the transport carriage is a rectangle that is long in the front-rear movement direction X, and the free wheels 1a to 1d are attached to the left and right end bottoms of the front and rear side frame panels 2, 3 in the front-rear movement direction X. One of the frame panels 2 and 3 can be folded inside the back frame panel 4 provided only on the left and right sides, and the loading platform 5 supported by the lower sides of these three panels 2 to 4 can be removed. Alternatively, in the transport cart configured to be foldable inside any one of the panels 2 to 4 and configured to be nestable by folding a cart that is not used in an L shape in plan view, for steering each of the free wheels 1a to 1d. When the rotational axis SC is viewed from the lateral direction Y with respect to the longitudinal movement direction X defined on the carriage, the steering rotational axis SC of the front and rear universal wheels 1a, 1b (1c, 1d) To be It can be tilts, respectively.
[0009]
Further, each of the universal wheels 1a to 1d is inclined as described above when the steering rotation axis SC is viewed from the lateral direction Y and is not inclined as described above, or is not inclined or has a gentle inclination angle. When a load exceeding a certain level is applied to the transporting carriage, and an elastic body (plate spring 17) that is urged to the tilting action posture is also provided. In addition, each of the free wheels 1a to 1d can be configured to swing against the urging force of the elastic body (leaf spring 17) and switch to the non-inclined posture.
[0010]
Further, each of the universal wheels 1a to 1d has a tilting action posture in which the steering rotation axis SC is inclined as described above when viewed from the left-right lateral direction Y and a non-inclined posture in which the inclination is not inclined or the inclination angle is gentle. Are supported by the mounting base 6 so as to be swingable between the movable wheels 1a to 1d, and the elastic bodies (plate springs 17) are urged to be non-inclined by the elastic body and transported. When a certain load or more is applied to the carriage, each of the free wheels 1a to 1d swings against the urging force of the elastic elastic body (leaf spring 17) and switches to the tilting action posture. It is also possible to configure.
[0011]
Further, when the rotational axis SC for steering of each universal wheel is viewed from the front-rear movement direction X defined on the carriage, the rotational axis SC for steering of both the left and right universal wheels is reverse C-shaped or C-shaped. Each can be tilted so that Further, the pair of left and right universal wheels 1a, 1c on one end side in the front-rear movement direction X defined on the carriage is inclined forward narrowed or forward spread in plan view, and the pair of left and right universal wheels 1b, 1d on the other end side are It is also possible to incline the pair of left and right universal wheels 1a and 1c on the one end side so as to be symmetric.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. The transport carriage in this preferred embodiment is a transport cart that can be nested as described above with reference to FIGS. The free wheels 1a to 1d are attached to the bottom four corners of the bottom, that is, the bottom left and right ends of the front and rear side frame panels 2, 3 in the front and rear movement direction X of the transport carriage whose planar shape is a rectangle long in the front and rear movement direction X. However, as shown in FIG. 5, all the free wheels 1 a to 1 d are provided under the mounting base portion 6, and the axis SC is perpendicular to the mounting base portion 6. A fork-like wheel support member 8 is rotatably supported around a steering rotation shaft 7 inclined by a predetermined angle with respect to a vertical line, and the wheel 9 is supported by the wheel shaft support member 8 with its axis being the axis. Horizontally at a position one side away from the rotational axis SC for steering Those which are pivotally supported capable of rotating by a shaft 10. 11 and 12 are ball bearings that sandwich the wheel support member 8 from above and below around the steering shaft 7.
[0013]
As shown in FIG. 6, the free wheel 1 a to 1 d having the above-described configuration is such that the steering rotation axis SC of each of the free wheels 1 a to 1 d has a lateral Y direction (see FIG. 1) with respect to the longitudinal movement direction X defined for the carriage. As seen from the reference), the front and rear free side frames 1a, 1b (1c, 1d) are arranged in the direction in which the rotational axis SC for steering becomes a reverse C-shape through the mounting base 6 respectively. The panels 2 and 3 are attached to the bottoms at the left and right ends.
[0014]
According to the transport carriage having the above-described configuration, the wheel 9 (wheel support member 8) of each of the universal wheels 1a to 1d operates because the steering rotation axis SC is inclined as shown in FIG. A rotational force around the steering rotational axis SC, that is, a restoring force is received in a direction in which the floor surface height of the mounting base portion 6 is lowest due to the load. Therefore, normally, each of the free wheels 1a to 1d is used for steering the front and rear free wheels 1a and 1b (1c and 1d) when the free wheels 1a to 1d are viewed from the lateral direction Y as shown in FIG. The rotation axis SC is stable in the initial state where it becomes a reverse C shape. In other words, even if the direction of the universal wheels 1a to 1d is turned against the restoring force by pushing the carriage for sideways or the like, when the operating force is released, each of the free wheels 1a to 1d is released by the restoring force. 1d automatically returns to the initial state. This restoring force increases as the inclination angle of the steering rotation axis SC increases, and increases as the load acting on the transfer carriage increases, so when the transfer carriage is empty as in the case of nesting, It is desirable to set the inclination angle of the steering rotation axis SC so that the rotational resistance around the steering rotation axis SC is greater than or equal to the restoring force.
[0015]
Thus, when the transport carriage is manually pushed forward (or rearward) in the front-rear movement direction X, as shown by a solid line (or virtual line) in FIG. The pair of left and right universal wheels 1a, 1c (or 1b, 1d) on the front side in the direction move while maintaining the initial posture in which the steering rotation axis SC is located rearward in the movement direction toward the lower side. The pair of left and right universal wheels 1b, 1d (or 1a, 1c), in which the ground contact resistance of the wheel 9 wins over the restoring force, moves from the initial position around the steering rotation axis SC. Rotate to the rear side, and follow and move at the rear position of the steering rotation axis SC in the same manner as the free wheels 1a, 1c (or 1b, 1d) on the front side in the movement direction. That is, since the pair of left and right universal wheels 1a, 1c (or 1b, 1d) on the front side in the movement direction maintain the initial posture by both the restoring force and the ground contact resistance of the wheel 9, The pair of left and right universal wheels 1b, 1d (or 1a, 1c), which are straight in the direction of the moving direction, exhibit almost straight movement as in the case of a fixed wheel and hardly move in the lateral direction with respect to the moving direction. Acts in the opposite direction, so that the straight running performance is lower than that of the front universal wheels 1a, 1c (or 1b, 1d), but during the movement, the rear position of the steering rotation axis SC due to the ground contact resistance of the wheels 9 It maintains the posture of following and moving, and functions as much as a conventional free wheel. Therefore, as a whole, the transport carriage can be moved straight forward in the forward / backward direction X (or rearward) without wobbling in the lateral direction. Of course, applying a left / right lateral steering force to the rear end side of the carriage with respect to the moving direction to bend the moving direction to the left / right lateral direction is a pair of left and right universal wheels 1b, 1d (or 1a, 1c) on the rear side of the moving direction. ) Is in a state where it is easy to rotate around the steering axis SC by the restoring force, and the front free wheels 1a, 1c (or 1b, 1d) are also steered from the fixed axis. It can be easily performed from what can be rotated around the SC, and there is no problem in maneuverability.
[0016]
When the carriage is empty when no load is loaded on the loading platform 5, the vertical load acting on each of the free wheels 1a to 1d is small and the restoring force to the initial posture is remarkably reduced. It is also relatively easy to translate the trolley in the lateral and lateral directions and the oblique direction. Therefore, when the trolley is nested in a planar shape in an L shape as shown in FIG. 2, nesting can be performed more easily than a conventional pair of front left and right wheels.
[0017]
Basically, as shown in FIG. 7, the steering rotation axis SC of each of the free wheels 1 a to 1 d is vertical and parallel to each other when viewed from the front-rear movement direction X defined on the carriage. In order to further improve the straightness, as shown in FIG. 8, the steering rotation axis SC of each of the free wheels 1a to 1d is also viewed from the back-and-forth movement direction X defined on the carriage. It can be attached in a direction that becomes a reverse C shape (upwardly spread state, with a normal camber angle), and conversely, as shown in FIG. 9, for the steering of each of the free wheels 1a to 1d. The rotation axis SC can also be attached in a direction that becomes a C-shape (downward spread state) when viewed from the front-rear movement direction X defined on the carriage. As another method for improving the straight traveling performance, as shown in FIG. 10, the pair of left and right universal wheels 1a and 1c on one end side in the front-rear movement direction X defined on the carriage are each narrowed forward (toe-in state) in plan view. The pair of left and right universal wheels 1b and 1d on the other end side are symmetrical with the pair of left and right universal wheels 1a and 1c on the other end side. It is also possible to incline each so as to be.
[0018]
In the state shown in FIGS. 8 to 10, when the mounting base 6 is attached to the left and right end bottoms of the front and rear side frame panels 2 and 3, the mounting base 6 is placed around the vertical axis. It is only necessary to change the direction in which the steering rotation shaft 7 is tilted by rotation, but in this method, the steering rotation shaft of each of the free wheels 1a to 1d from the lateral direction Y with respect to the longitudinal movement direction X determined for the carriage. Since the inclination angle (see FIG. 6) when looking at the center SC also changes at the same time, when the mounting base 6 is attached to the left and right both bottoms of the front and rear side frame panels 2, 3, The inclination angle of the steering rotation axis SC when viewed from the lateral direction Y (see FIG. 6) and the inclination angle of the steering rotation axis SC when viewed from the front-rear movement direction X (see FIG. 8 or FIG. 9). ) Or the horizontal and horizontal inclination angles (see FIG. 10) in plan view are respectively predetermined values. To configure to be desirable.
[0019]
The universal wheel 13 shown in FIG. 11 does not support the wheel support member 8 on the mounting base portion 6 directly by the steering rotating shaft 7, and the intermediate movable member 14 is interposed below the mounting base portion 6. The wheel support member 8 is supported by the intermediate movable member 14 via the steering rotating shaft 7, and one end portion of the intermediate movable member 14 is supported on one end of the mounting base portion 6 so as to be swingable up and down. A support portion 15 is provided, and a receiving portion 16 for receiving the free end portion of the intermediate movable member 14 is provided at the other end of the mounting base portion 6. The intermediate movable member 14 faces downward toward the receiving portion 16. A leaf spring 17 as an elastic body that presses and urges the free end portion is interposed between the mounting base portion 6 and the intermediate movable member 14. Specifically, the leaf spring 17 has a downwardly convex arc shape, the downward convex portion is fixed on the free end portion of the intermediate movable member 14, and both free ends of the leaf spring 17 are attached to the mounting base. It is in pressure contact with the lower surface of the base 6.
[0020]
Thus, as shown in FIG. 11A, the intermediate movable member 14 is received by the receiving portion 16 by the urging force of the leaf spring 17, and the intermediate movable member 14 with respect to the horizontal mounting base portion 6. However, when the free end portion is tilted so that the free end portion is lowered, the steering rotation axis SC perpendicular to the intermediate movable member 14 is inclined with respect to the horizontal mounting base portion 6. It will be. Then, as shown in FIG. 11C, the intermediate movable member 14 swings upward to the upper limit around the support portion 15 against the urging force of the leaf spring 17 with respect to the horizontal mounting base portion 6. Then, the intermediate movable member 14 becomes horizontal or near-horizontal, and the steering rotation axis SC is in a non-inclined posture at a right angle or slightly inclined with respect to the horizontal mounting base portion 6.
[0021]
When the universal wheel 13 having the above-described configuration is used as the universal wheels 1a to 1d in the transporting carriage, the steering rotation axis SC in which the universal wheel 13 in the inclination action posture shown in FIG. 11A is inclined is shown in FIG. The four universal wheels 13 may be attached with their orientations of the mounting base portions 6 determined so as to incline in the directions. By using in this way, when the transport carriage is empty or light, each of the free wheels 1a to 1d (13) provided with the steering shaft SC that tilts as shown in FIG. When the tilt angle of the steering rotation shaft SC becomes larger (tilt action posture), and on the contrary, the loading amount of the transport carriage is large and the vertical load acting on each of the free wheels 1a to 1d (13) becomes large. The inclination angle of the steering rotation axis SC of each of the free wheels 1a to 1d (13) becomes small (non-inclined posture). In the state shown in FIG. 6, if the inclination angle of the steering rotation axis SC of each of the free wheels 1a to 1d (13) is small, the restoring force for returning to the initial state shown in FIG. Although it is in the same state as the wheels, since the loading capacity of the transport carriage is large and the ground pressure of each of the free wheels 1a to 1d (13) increases, the transport carriage to be pushed and moved is less likely to fluctuate from side to side. In addition, it can be moved relatively straight forward and the direction can be changed easily. Conversely, in the state shown in FIG. 6, if the inclination angle of the steering rotation axis SC of each of the free wheels 1 a to 1 d (13) is large, the straight traveling performance in the front-rear movement direction X is improved. Since it is in an empty or light load state, it can be changed in direction or translated obliquely relatively easily by a manual operation.
[0022]
The universal wheel 18 shown in FIG. 12 has the same reference numerals as those of the universal wheel 13 shown in FIG. 11 and the description thereof will be omitted. However, the universal wheel 13 shown in FIG. And the urging end of the leaf spring 17 are reversed in the front-rear direction. That is, in the universal wheel 18 shown in FIG. 12, as shown in FIG. 12A, the free end of the intermediate movable member 14 is supported by the receiving portion 16 of the mounting base portion 6 by the urging force of the leaf spring 17. The intermediate movable member 14 is in a substantially horizontal posture parallel to the mounting base portion 6. Therefore, the steering rotational axis SC perpendicular to the intermediate movable member 14 has a horizontal mounting base portion. 6 is substantially perpendicular (non-tilted posture). When the intermediate movable member 14 swings upward against the urging force of the leaf spring 17 around the support portion 15 due to the load, the intermediate movable member 14 with respect to the mounting base portion 6 as shown in FIG. 12C. Is tilted, and the steering rotation axis SC perpendicular to the intermediate movable member 14 is inclined with respect to the horizontal mounting base portion 6 (inclination action posture).
[0023]
When the universal wheel 18 having the above-described configuration is used as the universal wheels 1a to 1d in the transporting carriage, the steering rotation axis SC that inclines when the inclination acting posture shown in FIG. The four universal wheels 18 may be attached so as to incline with their orientations of the mounting base portions 6 determined. By using in this way, when the carrying amount of the transport traveling body is large and the vertical load acting on each of the free wheels 1a to 1d (13) becomes large, the steering of each of the free wheels 1a to 1d (13) is performed. As shown in FIG. 12C, the inclination angle of the rotation axis SC for use is increased (inclination posture), and the initial state shown in FIG. 6 is obtained. Conversely, when the carriage is empty or lightly loaded, As shown in FIG. 12A, the inclination angle of the steering rotation axis SC of each of the universal wheels 1a to 1d (13) of the carriage is reduced or becomes zero (vertical) (non-inclined posture). That is, when the loading capacity of the transport carriage is large, the initial state shown in FIG. 6 is obtained, so that the straight traveling performance in the forward / backward movement direction X is greatly improved, but conversely, the transport carriage is empty or lightly loaded. In this case, the situation is the same as when a normal universal wheel is used, and it can be moved easily in a free direction by a hand pushing operation, which is suitable for a nesting operation or the like.
[0024]
11 and 12, the structure of the support portion 15 that supports one end portion of the intermediate movable member 14 so as to be swingable up and down is not limited to that shown in the figure, and for example, another support portion is supported. A configuration using an axis may also be used. Further, although the leaf spring 17 is used as an elastic body for urging the intermediate movable member 14, any configuration such as a coil spring or a rubber block may be used, and the interposition structure is not limited to the illustrated example.
[0025]
【The invention's effect】
The present invention can be implemented and used as described above, and according to the transport carriage of the present invention, since all four wheels are free wheels, the transport traveling body is empty. When the load is light or light, it is possible to easily move lightly and easily in any direction by taking advantage of the characteristic that all wheels are free wheels. In addition, as the loading capacity of the transport carriage increases, the straightness in the forward / backward movement direction defined for the transport carriage increases, and the straight forward movement can be stably performed. Because the free wheel on the side is less straight forward than the free wheel on the front side, the rear end side with respect to the moving direction is steered in the horizontal and horizontal directions in the same way as the conventional carriage for the front fixed wheel and the rear free wheel. It also has the feature that the operation to change the direction of movement can be done relatively easily. Of course, basically, no special movable member is required for mounting the free wheel, so that it can be carried out inexpensively and easily, and the improvement of the conventional existing carriage is easy.
[0026]
In addition, if the present invention is applied to a carriage that can be nested by folding a carriage that is not used in an L shape in plan view as described in claim 2, the straight traveling performance is exhibited at the time of loading and carrying work. Nesting work can be easily translated in an oblique direction by taking advantage of the fact that all wheels are free wheels when nesting in the folded state of an empty transport cart, even though it is a transport cart. Work can be done easily and easily.
[0027]
In addition, according to the configuration of claim 3, as the carrying load of the transport carriage increases, all the free wheels become the same as normal free wheels with the steering rotation axis in the vertical state, and the maneuverability is improved. Can be suppressed from being extremely reduced. On the contrary, according to the configuration of claim 4, as the loading load of the transport carriage increases, the straight traveling performance of the transport carriage in the front-rear movement direction is improved, and can be stably moved straight forward, When the vehicle is empty or lightly loaded, the straightness of the transfer carriage is almost lost, so that the empty transfer cart can be arranged very easily.
[0028]
Furthermore, it can comprise as described in Claim 5 and Claim 6, and can further improve the straight-ahead performance of the back-and-forth movement direction of the conveyance trolley | bogie. Of course, the effects can be enhanced by combining the configurations described in the claims.
[Brief description of the drawings]
FIG. 1 is a perspective view of an entire conveyance carriage.
FIG. 2 is a plan view showing a folded state of the transport carriage shown in FIG.
FIG. 3A is a schematic plan view showing a straight traveling state when the transport carriage shown in FIG. 1 is a front fixed wheel and a rear free wheel, and FIG. B is a state during nesting work of the transport carriage. It is a schematic plan view which shows.
4 is a schematic plan view showing a state during a nesting operation in a case where all the wheels of the transport carriage shown in FIG. 1 are free wheels. FIG.
FIG. 5 is a partially longitudinal side view showing a universal wheel used in the present invention.
6 is a partially cutaway side view of a transport carriage using the universal wheel shown in FIG. 5. FIG.
FIG. 7 is a partially cutaway front view of the transport carriage.
FIG. 8 is a partially cutaway front view showing a modified example of the transport carriage.
FIG. 9 is a partially cutaway front view showing still another modified example of the transport carriage.
FIG. 10 is a schematic plan view showing still another modified example of the transport carriage.
FIG. 11 is a view showing a modification of the free wheel used in the present invention, in which FIG. A is a partially longitudinal side view in a tilting action posture, B is a partially longitudinal front view, and C is a non-tilting posture. It is a partially vertical side view in FIG.
FIG. 12 is a view showing still another modified example of the universal wheel used in the present invention, in which FIG. A is a partially longitudinal side view in a non-inclined posture, B is a partially longitudinal front view, and FIG. It is a partial vertical side view in a tilting action posture.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1a-1d Swivel wheel 2,3 Front and back side frame panel 4 Back frame panel 5 Foldable loading platform 6 Mounting base part 7 Steering rotation shaft 8 Wheel support member 9 Wheel 10 Horizontal support shafts 13 and 18 Universal wheel 14 Intermediate movable member 15 Bearing portion 16 Receiving portion 17 Leaf spring (elastic body)
SC Steering rotation axis X Forward / backward movement direction of transport carriage Y Left / right lateral direction of transport carriage

Claims (6)

It is a transporting carriage with wheels attached in the vicinity of the bottom four corners, and all four wheels are freewheels, and the steering rotation axis SC of each freewheel is in the longitudinal movement direction X defined for the carriage. On the other hand, when viewed from the left-right lateral direction Y, the transport carriage is tilted so that the steering rotation axis SC of the front and rear free wheel is in a reverse C shape. The planar shape of the transport carriage is a rectangle that is long in the front-rear movement direction X, and the universal wheels are attached to the left and right ends of the front and rear side frame panels in the front-rear movement direction X. One side can be folded inside the back frame panel provided only on the left and right sides, and the loading platform supported by the lower sides of these three panels can be removed or folded inside any panel. The carriage according to claim 1, wherein the carriage is configured to be nestable by folding an unused carriage in an L shape in a plan view. Each of the universal wheels swings between a tilting posture in which the steering rotation axis SC is tilted as described above when viewed from the left-right lateral direction Y and a non-tilted posture in which the tilting angle is not tilted or has a gentle tilt angle. An elastic body that is movably supported by the mounting base portion and urged to the tilting posture is provided, and when a load of a certain level or more is applied to the transport carriage, each of the free wheels is attached to the elastic body. The carriage according to claim 1 or 2, wherein the carriage is configured to swing against an urging force and to switch to the non-tilt posture. Each of the universal wheels swings between a tilting posture in which the steering rotation axis SC is tilted as described above when viewed from the left-right lateral direction Y and a non-tilted posture in which the tilting angle is not tilted or has a gentle tilt angle. An elastic body that is movably supported by the mounting base and is urged in the non-tilt posture is provided, and when a load of a certain level or more is applied to the transport carriage, each of the free wheels is attached to the elastic body. The carriage for transfer according to claim 1 or 2, wherein the carriage is configured to swing against an urging force and switch to the tilting action posture. When the rotational axis SC for steering of each of the free wheels is viewed from the front-rear movement direction X defined on the carriage, the rotational axis SC for steering of the left and right universal wheels has a reverse C-shape or C-shape. As described above, the carriage for transportation according to any one of claims 1 to 4, wherein each is inclined. A pair of left and right universal wheels on one end side in the front-rear movement direction X defined in the carriage is inclined forward narrowing or frontward in plan view, and the pair of left and right universal wheels on the other end side is a pair of left and right free wheels on the one end side. The transport carriage according to any one of claims 1 to 5, wherein the transport carriage is inclined so as to be symmetrical with the wheels.

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