Transport dolly

Abstract

To inhibit increase in size of a transport dolly.SOLUTION: A transport dolly 10 of the invention includes: a dolly main part 20; casters 41A located at four corners of the dolly main part 20; and a first mounting part 80a and a second mounting part 80b which are located spaced apart from each other in a front-back direction of the dolly main part 20. The first mounting part 80a and the second mounting part 80b may be shifted between a first state where the first mounting part 80a and the second mounting part 80b are located on an upper surface of the dolly main part 20 and a second state where the first mounting part 80a and the second mounting part 80b are spaced apart from the upper surface of the dolly main part 20. In the first state and the second state, the first mounting part 80a and the second mounting part 80b overlap an area of the dolly main part 20 in plan view.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a transport cart. [Background technology]

[0002] Transport carts are used to transport goods at work sites, etc. Patent Document 1 discloses a transport cart that can use a forklift to lift just the load from the cart body or to lift the entire cart. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-137690 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to prevent the size of the transport cart from increasing. [Means for solving the problem]

[0005] The present invention provides a transport cart comprising a cart main body, casters located at the four corners of the cart main body, and a first mounting section and a second mounting section located at a distance in the fore-and-aft direction of the cart main body, wherein the first mounting section and the second mounting section are capable of transitioning between a first state in which they are located on the top surface of the cart main body and a second state in which they are spaced apart from the top surface of the cart main body, and in the first and second states they overlap with the area of ​​the cart main body in a planar view. [Effects of the Invention]

[0006] According to the present invention, it is possible to prevent the size of the transport cart from increasing. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing an example of the configuration of a transporter truck according to a first embodiment. [Figure 2] FIG. 2 is a bottom view showing an example of the configuration of the transport cart. [Figure 3] FIG. 2 is a plan view showing an example of the configuration of a transport cart. [Figure 4] FIG. 2 is a side view showing an example of the configuration of the transport cart. [Figure 5] FIG. 2 is a rear view showing an example of the configuration of the transport cart. [Figure 6] FIG. 10 is a perspective view showing the caster in an exploded state. [Figure 7] FIG. 10 is a perspective view showing a state in which the caster is coupled to the mounting member. [Figure 8] FIG. 10 is a side view showing an example of a state in which a transported object is placed. [Figure 9] FIG. 10 is a bottom view showing the swivel position where the casters are locked from swivel. [Figure 10] 10A and 10B are perspective views showing states before and after the swivel of the casters is locked. [Figure 11] 10A and 10B are cross-sectional views showing the states before and after the swivel of the casters is locked. [Figure 12] FIG. 10 is a side view showing an example of a state in which the transport carts are stacked. [Figure 13] FIG. 10 is a perspective view showing an example of the configuration of a transporter truck according to a second embodiment. [Figure 14] FIG. 2 is a bottom view showing an example of the configuration of the transport cart. [Figure 15] FIG. 2 is a plan view showing an example of the configuration of a transport cart. [Figure 16] FIG. 10 is a perspective view showing a locked member according to a third embodiment. [Figure 17] FIG. 10 is a side view showing an example of the configuration of a transporter vehicle according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] The transport vehicle according to this embodiment will be described with reference to the drawings. First Embodiment FIG. 1 is a perspective view showing an example of the configuration of the transporter 10. FIG. 2 is a bottom view showing an example of the configuration of the transporter 10. FIG. 3 is a plan view showing an example of the configuration of the transporter 10. FIG. 4 is a side view showing an example of the configuration of the transporter 10. FIG. 5 is a rear view of the transporter 10 as seen from the rear. In each figure, including those described below, the direction of travel of the transporter 10 is defined as the front-rear direction, with the front side indicated as Fr, the rear side as Rr, the right side as R, and the left side as L. The center of the transporter 10 in the left-right direction is indicated as center line C1, and the center in the front-rear direction is indicated as center line C2. Therefore, the side view of FIG. 4 is a view seen from the side perpendicular to the direction of travel of the transporter 10. The transporter 10 of this embodiment can travel in any direction, including front-rear, left-right, and not limited to the front-rear direction.

[0009] The transport cart 10 includes a cart main body 20, a running section 40, and placement sections 80a and 80b. The bogie main body 20 is formed by connecting a plurality of frame sections and the like, and is used to carry transported goods. When viewed from above (or from the bottom), the bogie main body 20 has a generally rectangular shape with the longitudinal direction being the front-to-rear direction (first direction) and the lateral direction being the left-to-right direction (second direction) perpendicular to the front-to-rear direction. The bogie main body 20 is configured to be generally symmetrical with respect to the center line C1. The bogie main body 20 is also configured to be generally symmetrical with respect to the center line C2. The bogie body 20 has a front frame portion 21a, a rear frame portion 21b, a right frame portion 21c, a left frame portion 21d, corner members 22, reinforcing portions 25, mounting portions 30, and the like.

[0010] The front frame portion 21a, the rear frame portion 21b, the right frame portion 21c, and the left frame portion 21d form the outer shape of the bogie main body portion 20. The front frame portion 21a, the rear frame portion 21b, the right frame portion 21c, and the left frame portion 21d are joined at their four corners by corner members 22 to form a substantially rectangular four-sided frame frame. The front frame portion 21a, the rear frame portion 21b, the right frame portion 21c, and the left frame portion 21d can be formed, for example, from rectangular hollow pipes made of aluminum alloy.

[0011] The corner members 22 connect adjacent frame members among the front frame member 21a, the rear frame member 21b, the right frame member 21c, and the left frame member 21d at their four corners. The corner members 22 also function as mounting members for attaching the push member 70 to the cart main body 20. The corner members 22 have an insertion hole 23 that opens upward into which the push member 70 is inserted, and a support portion 24 that supports the push member 70 inserted into the insertion hole 23. The corner members 22 can be made of, for example, an aluminum alloy member formed by extrusion molding.

[0012] In each figure, the push member 70 is indicated by a two-dot chain line. The push member 70 is a member that the user grasps with their hands when moving the transport cart 10. The user grasps the push member 70 with their hands and pushes or pulls the transport cart 10 to move it. The push member 70 is attached to the cart main body 20 by inserting it into the insertion hole 23 of the corner member 22, and is removed from the cart main body 20 by removing it from the insertion hole 23.

[0013] As shown in FIG. 1, the push member 70 has a main body member 71 and a protection member 72. The main body member 71 is a long, straight rod-like member or a long, pipe-like member. The main body member 71 is made of, for example, an aluminum alloy and is formed by extrusion molding. The protective member 72 protects the user's hands from coming into contact with surrounding objects when the user grasps the push member 70. The protective member 72 is fixed to the upper side of the main body member 71 at a predetermined distance from the upper end with bolts, rivets, etc. The part of the push member 70 above the protective member 72 functions as a grip portion that the user grasps with their hand. The protective member 72 is disc-shaped and protrudes outward from the outer periphery of the main body member 71, and has a larger outer diameter than the main body member 71.

[0014] The reinforcing portion 25 reinforces the frame on all four sides of the bogie main body 20. As shown in FIGS. 2 and 3 , the reinforcing portion 25 has reinforcing frame portions 26a, 26b, 26c, 26d, 26e, and 26f. The reinforcing frame portions 26a, 26b, 26c, 26d, 26e, and 26f are joined by bolts, rivets, welding, or the like to the frame on all four sides or to each other in the front-rear and left-right directions, thereby reinforcing the bogie main body 20. The reinforcing frame portions 26a, 26b, 26c, 26d, 26e, and 26f may be, for example, rectangular hollow pipes made of an aluminum alloy. In addition, since the reinforcing portion 25 of this embodiment is configured to be approximately symmetrical in the front-rear direction with respect to the center line C2, the configuration of the front side of the reinforcing portion 25 will be mainly described, and the description of the configuration of the rear side will be omitted.

[0015] The reinforcing frame portions 26a, 26b, and 26c extend in the left-right direction and are installed across the right frame portion 21c and the left frame portion 21d. The reinforcing frame portions 26a, 26b, and 26c are arranged from the front side in the order of reinforcing frame portion 26a, reinforcing frame portion 26b, and reinforcing frame portion 26c, with a gap between them.

[0016] The reinforcing frame portions 26d, 26e, and 26f are each formed as a pair, spaced apart on the left and right. The reinforcing frame portion 26d extends in the front-to-rear direction and is provided between the front frame portion 21a and the reinforcing frame portion 26a. The reinforcing frame portion 26e extends in the front-to-rear direction and is provided between the reinforcing frame portions 26b and 26c. The reinforcing frame portion 26f extends in the front-to-rear direction and is provided between the reinforcing frame portions 26c and 26c so as to intersect with the center line C2.

[0017] The bogie main body 20 has a frame frame on all four sides partitioned by reinforcing frame portions 26a, 26b, 26c, 26d, 26e, and 26f, thereby forming a plurality of substantially rectangular spaces 27a, 27b, 27c, and 27d in a plan view. Space 27a is located at the four corners of the bogie main body 20. Space 27b is located in the center of the bogie main body 20 in the front-to-rear direction, separated from the left and right. Space 27c is located between reinforcing frame portion 26a and reinforcing frame portion 26b, separated from the front and rear. Space 27c is a space that is long in the left-to-right direction. Space 27d is a space other than spaces 27a to 27c.

[0018] The mounting section 30 mounts the running section 40 to each frame section and each reinforcing frame section of the carriage body section 20. The mounting section 30 has a plurality of (four) mounting members 31A and a plurality of (two) mounting members 31B. Mounting members 31A are positioned corresponding to spaces 27a at the four corners, and mounting members 31B are positioned corresponding to spaces 27b on the left and right of the center. Mounting members 31A and 31B are fixed to each frame portion and each reinforcing frame portion using bolts, rivets, etc. so as to close spaces 27a and 27b from below. Mounting member 31A has a rectangular shape in plan view with notched corners, and is made of, for example, a plate-like aluminum alloy. On the other hand, mounting member 31B has a rectangular shape in plan view with notched two adjacent corners, and is made of, for example, a plate-like aluminum alloy.

[0019] Space 27a in which mounting member 31A is disposed is open at the top and partially or entirely closed at the bottom by mounting member 31A. Space 27b in which mounting member 31B is disposed is open at the top and partially or entirely closed at the bottom by mounting member 31B. On the other hand, spaces 27c and 27d in which mounting members 31A and 31B are not disposed are penetrated in the vertical direction. When the same transport carts 10 are stacked, portions of casters 41A, 41B (described later) of the upper transport cart 10 enter into the spaces 27a, 27b closed by the mounting members 31A, 31B.

[0020] The running unit 40 runs on the floor while supporting the weight of the carriage body 20 and the load. The running unit 40 has a plurality of (four) casters 41A arranged at the four corners of the carriage body 20, and a plurality of (two) casters 41B arranged at the center in the front-to-rear direction and spaced apart on the left and right. The casters 41A are attached to the carriage body 20 via mounting members 31A, and the casters 41B are attached to the carriage body 20 via mounting members 31B.

[0021] The caster 41A is rotatable around a rotation axis O1, which is a vertical axis. The caster 41A is a brake-equipped caster that can be braked or released in response to an operation by the user.

[0022] The configuration of the caster 41A will now be described with reference to FIGS. Fig. 6 is a perspective view showing a state before the caster 41A is coupled to the mounting member 31A, with a part of the caster 41A disassembled. Fig. 7 is a perspective view showing a state after the caster 41A is coupled to the mounting member 31A. The caster 41A includes a wheel 42, a support portion 45, a brake pedal 55, a rotation lock mechanism 100, and the like.

[0023] The wheel 42 has a wheel portion 42a with a bearing built in, and a tire portion 42b fitted onto the outer periphery of the wheel portion 42a. The support portion 45 rotatably supports the wheel 42 via the axle 43. The support portion 45 supports the wheel 42 and includes a fork member 46 attached to the carriage body 20 via the attachment member 31A, and a pedal holding member 51 supporting the brake pedal 55 so that the brake pedal 55 can swing.

[0024] The fork member 46 is integrally formed of a pair of side walls 46a located on either side of the wheel 42, and a circular top plate 46b that connects the pair of side walls 46a above the wheel 42. The top plate 46b is sandwiched between an upper dish member 47 and a lower dish member 48 via bearings 49 and 50, which will be described later (see FIG. 11, which will be described later).

[0025] An insertion hole 46e is formed in the center of the top plate 46b, coaxial with the rotation axis O1 of the caster 41A. The upper tray member 47 is formed in a circular shape that is slightly larger than the top plate 46b, and has an insertion hole 47a formed in the center coaxial with the rotation axis O1. The lower tray member 48 is formed in a circular shape that is smaller than the top plate 46b, and has an insertion hole 48a formed in the center coaxial with the rotation axis O1. The upper tray member 47 and the lower tray member 48 are integrally joined so as to prevent relative rotation in the vicinity of the insertion holes 47a and 48a. Therefore, the top plate 46b, i.e., the fork member 46, can rotate about the pivot axis O1 relative to the upper tray member 47 and the lower tray member 48 via bearings 49 and 50.

[0026] The pedal holding member 51 is integrally formed by a pair of side walls 51a located on both sides of the wheel 42 and a connecting plate 51b connecting the pair of side walls 51a at the upper side. The pair of side walls 51a extend in different directions from the connecting plate 51b in a bifurcated shape, with one side of the bifurcated shape supported by the axle 43 together with the fork member 46 at the lower side and the other side supported by the shaft member 52 at the upper side. A shaft member 56 that supports a brake pedal 55 in a swingable manner is inserted into the upper part of the side walls 51a at a position close to the connecting plate 51b.

[0027] The brake pedal 55 applies the brakes to the wheels 42 in response to operation by the user. The brake pedal 55 has a pedal body 55a and an operating piece 55b as a pedal operating portion that extends integrally from the pedal body 55a. The pedal body 55a is integrally formed with a pair of side walls located on both sides of the wheels 42 and a connecting plate that connects the pair of side walls at the top. When the caster 41A is viewed in the direction of travel, the brake pedal 55 is positioned so as to overlap the wheels 42. The brake pedal 55 can swing up and down relative to the pedal holding member 51 around a shaft member 56. When the user operates the operation piece 55b with his / her foot or the like, the brake pedal 55 swings up and down.

[0028] When the brake is released, the brake pedal 55 is in a raised position. On the other hand, when the user operates the brake pedal 55 by pressing the operating piece 55b downward with their foot, the brake pedal 55 swings downward. Note that the brake pedal 55 shown in each figure is in a released state. As the brake pedal 55 swings downward, the brake pedal 55 directly or indirectly presses firmly against the outer circumferential surface of the wheel 42, preventing the wheel 42 from rotating and placing the brake in an applied state. Furthermore, the brake pedal 55 functions as a stopper because it is maintained in the applied state.

[0029] The swivel lock mechanism 100 locks the swivel of the caster 41A. The swivel lock mechanism 100 has a support member 110, a locking member 120, and a locked member 130. In this embodiment, the support member 110 and the locking member 120 are located on the fork member 46, which is the swivel side, and the locked member 130 is located on the carriage main body 20, which is the fixed side. In other words, when the caster 41A swivels, the support member 110 and the locking member 120 swivel in synchronization with the fork member 46, and the locked member 130 does not swivel, and its relative position with the carriage main body 20 is maintained.

[0030] The support member 110 supports the locking member 120. The support member 110 is connected to the fork member 46 at a position opposite the pedal holding member 51 across the pivot axis O1. The support member 110 has a pair of side walls 111 and a connecting portion 112 connecting the pair of side walls 111 at their upper sides. The support member 110 is formed, for example, by pressing a metal plate. The pair of side walls 111 have recesses 113 formed at their rear ends. The recesses 113 engage with the shaft member 52 when the support member 110 is connected to the fork member 46, thereby positioning the support member 110. The pair of side walls 111 are suspended by shaft members 114 and 115 spaced apart from each other in the front-to-rear direction. The support member 110 rotatably supports the locking member 120 via the shaft member 114. The shaft member 115 is located in an elongated hole that is long in the front-to-rear direction of the pair of side walls 111 and is movable within the elongated hole. A biasing member 116 is bridged between the shaft members 114 and 115 (see FIG. 11). Therefore, the shaft members 114 and 115 are biased in directions toward each other by the biasing member 116. The pair of side walls 111 also have shaft holes 118 into which fixing bolts 117 for connecting the support member 110 to the fork member 46 are inserted.

[0031] The locking member 120 locks the rotation of the caster 41 by engaging with the locked portion 132 of the locked member 130. The locking member 120 is rotatably supported on the support member 110 via the shaft member 114. The locking member 120 has a pair of side walls 121 and a connecting portion 122 that connects the pair of side walls 121 at their front ends. The locking member 120 is formed, for example, by pressing a metal plate. The pair of side walls 121 have a first positioning portion 123a and a second positioning portion 123b at their rear ends (see FIG. 11). The first positioning portion 123a and the second positioning portion 123b are positioned vertically apart and have an arc shape that is concave toward the front. The rotation of the locking member 120 is positioned by engaging either the first positioning portion 123a or the second positioning portion 123b with the shaft member 115.

[0032] The connecting portion 122 has a locking portion 124 on the upper side and an operating portion 125 on the lower side. In response to operation by the user, the locking portion 124 engages with the locked portion 132 of the locked member 130 to lock the rotation of the caster 41A. The locking portion 124 is a plate-like member integrally formed of a wide portion 124a located on the lower side and a narrow portion 124b located on the upper side. The wide portion 124a gradually narrows toward the upper side, while the narrow portion 124b has a substantially constant width. Note that the width here refers to the horizontal length of the locking portion 124 when viewed from a direction perpendicular to the axle 43. The narrow portion 124b of the locking portion 124 engages with the locked portion 132. As the locking member 120 rotates about the shaft member 114, the locking portion 124 moves in the front-to-rear direction. Specifically, when the locking portion 124 moves toward the pivot axis O1, the locking portion 124 engages with the locked portion 132, and when the locking portion 124 moves away from the pivot axis O1, the engagement between the locking portion 124 and the locked portion 132 is released.

[0033] The operating unit 125 is operated by a user when the user wishes to release the engagement between the locking unit 124 and the locked unit 132. The operating unit 125 has multiple anti-slip ridges 125a protruding from the front surface across the width. When the locking unit 124 is engaged with the locked unit 132, the user operates the operating unit 125 by, for example, using their foot to push the operating unit 125 toward the pivot axis O1. By operating the operating unit 125 toward the pivot axis O1, the locking member 120 rotates about the shaft member 114, and the engagement between the locking unit 124 and the locked unit 132 is released.

[0034] The locking member 130 is engaged with the locking portion 124 of the locking member 120. When the fork member 46 of the caster 41A is coupled to the mounting member 31A, the locking member 130 is disposed between the fork member 46 (specifically, the upper tray member 47) and the mounting member 31A, and is fixed to the mounting member 31A. The locking member 130 is formed in a substantially flat, circular plate shape centered on the pivot axis O1. The locking member 130 is formed, for example, by press-working a plate-shaped metal plate. The locking member 130 has an insertion hole 131 in its center that is coaxial with the pivot axis O1.

[0035] The lockable member 130 also has a lockable portion 132 on a part of the outer periphery. The locked portion 132 engages with the locking portion 124 of the locking member 120. The locked member 130 has a step 133 that is stepped downward over a certain range of its outer periphery. The locked portion 132 has a concave shape within the step 133 that faces the pivot axis O1. The locked portion 132 gradually narrows in width toward the pivot axis O1. In other words, the locked portion 132 gradually widens in width as it moves away from the pivot axis O1. The center of the width of the locked portion 132 is indicated by a center line S. The position of the locked portion 132 that engages with the locking portion 124 has a width WB, which is approximately the same as the width WA of the narrow portion 124b of the locking portion 124 (see Figure 10(a) described below).

[0036] To couple the support member 110 of the swivel lock mechanism 100 to the fork member 46 of the caster 41, the lock member 120 is first assembled to the support member 110 in a rotatable state, and the support member 110 is then coupled to the fork member 46 of the caster 41. Specifically, the support member 110 is inserted between the pair of side walls 46a of the fork member 46, and the shaft member 52 supporting the pedal holding member 51 is engaged with the recess 113 of the support member 110, thereby positioning the support member 110. Next, the shaft holes 46c formed in each of the pair of side walls 46a of the fork member 46 are communicated with the shaft holes 118 in the pair of side walls 111 of the support member 110, and a fixing bolt 117 is inserted and fixed, thereby coupling the support member 110 in a state in which the lock member 120 is supported to the fork member 46.

[0037] When the support member 110 is coupled to the fork member 46 of the caster 41A, the brake mechanism and the rotation lock mechanism are located on opposite sides of the rotation axis O1. That is, the lock portion 124 of the lock member 120 and the brake pedal 55 are located on opposite sides of the rotation axis O1. Also, the operation portion 125 of the lock member 120 and the operation piece 55b of the brake pedal 55 are located on opposite sides of the rotation axis O1.

[0038] To connect the lockable member 130 of the swivel lock mechanism 100 to the fork member 46 of the caster 41, the lockable member 130 is sandwiched between the upper tray member 47 and the mounting member 31A to connect to the fork member 46. Specifically, as shown in FIG. 6, from above the mounting member 31A, the bolt 60 is inserted through the insertion hole 62 of the washer member 61, the insertion hole 32 of the mounting member 31A, the insertion hole 131 of the lockable member 130, the insertion hole 47a of the upper tray member 47, the insertion hole 46e of the top plate 46b of the fork member 46, and the insertion hole 48a of the lower tray member 48, in that order, and then the nut 63 is screwed between the pair of side walls 46a of the fork member 46 to secure the lockable member 130. Therefore, the lockable member 130 is fixed at a position between the mounting member 31A and the upper tray member 47.

[0039] Here, locked member 130 is fixed so that locked portion 132 is at a predetermined position relative to mounting member 31A. Specifically, locked portion 132 of locked member 130 is fixed so that it is positioned so that it points toward corner 34 (see FIG. 6) diagonally opposite the rectangular cutout portion of mounting member 31A. Note that locked portion 132 can be fixed at a predetermined position relative to mounting member 31A by positioning locked member 130 and mounting member 31A using projections and recesses, or by directly joining the two using fixing members such as bolts or rivets.

[0040] 7, when the caster 41A is coupled to the mounting member 31A, the caster 41A can rotate around the rotation axis O1. At this time, the support member 110 and the locking member 120 of the rotation lock mechanism 100 are coupled to the fork member 46, and therefore rotate in synchronization with the fork member 46. On the other hand, the locked member 130 does not rotate because it is fixed to the mounting member 31A.

[0041] By attaching the mounting members 31A to which the casters 41A are coupled to the four corners of the carriage body 20, the locked portions 132 are positioned below the carriage body 20 at predetermined positions when viewed from the bottom.

[0042] The caster 41B is swivelable around a vertical axis, the rotation axis O2. Unlike the caster 41A, the caster 41B is a brakeless caster. That is, the caster 41B does not include the brake-related components of the caster 41A. Specifically, the caster 41B has the wheel 42, the fork member 46 of the support portion 45, the rotation lock mechanism 100, etc., but does not include the pedal holding member 51 and the brake pedal 55.

[0043] To connect the locked member 130 of the swivel lock mechanism 100 to the fork member 46 of the caster 41B, the locked member 130 is connected to the fork member 46 by sandwiching it between the upper tray member 47 and the mounting member 31B. At this time, the locked portion 132 of the locked member 130 is fixed in a position that points toward the center 35 of the side between the two corners of the rectangle of the mounting member 31B where the rectangle is cut out (see FIG. 2). By attaching the mounting member 31B to which the caster 41B is coupled to the center of the cart main body 20, the locked portion 132 is located below the cart main body 20 in a predetermined position when viewed from the bottom.

[0044] By attaching the casters 41A, 41B to the carriage body 20 in this manner, the casters 41A, 41B can be rotated around the rotation axes O1, O2 relative to the carriage body 20. In Fig. 2, the loci T1, T2 of the casters 41A, 41B when the casters 41A, 41B rotate around the rotation axes O1, O2 are shown by two-dot chain lines. The locus T1 indicates the locus of the operating piece 55b of the brake pedal 55 of the caster 41A. The locus T2 indicates the locus of the rear end of the wheel 42 of the caster 41B.

[0045] Here, a part of the locus T1 protrudes outward from the outer periphery (the frame frames on all four sides) of the carriage main body 20 in a plan view (or a bottom view). Specifically, when the wheel 42 faces in the front-to-rear direction, the operation piece 55b protrudes rearward from the rear frame part 21b of the locus T1, and when the caster 41A is turned 90° and the wheel 42 faces left-to-right, the operation piece 55b protrudes from the left frame part 21d. On the other hand, when the caster 41A is turned 45° and the wheel 42 faces diagonally, the operation piece 55b overlaps with the corner member 22, and the operation piece 55b does not protrude from the carriage main body 20, or the amount of protrusion is small. Note that although the locus T1 of one caster 41A has been described here, the same applies to the loci of the other casters 41A.

[0046] On the other hand, the locus T2 does not extend beyond the outer periphery (framework on all four sides) of the bogie main body 20 in a plan view (or a bottom view), but when the wheels 42 face left and right and the rear ends of the wheels 42 face outward from the bogie main body 20, the casters 41B come close to the outer periphery of the bogie main body 20. On the other hand, when the wheels 42 face left and right and the rear ends of the wheels 42 face toward the center of the bogie main body 20 (the intersection of the center line C1 and the center line C2), the casters 41B move away from the outer periphery of the bogie main body 20. Note that the casters 41B may be configured to extend beyond the outer periphery of the bogie main body 20 when the wheels 42 face left and right and the rear ends of the wheels 42 face outward from the bogie main body 20.

[0047] The placement portions 80a and 80b can transition between a first state in which they are positioned on the upper surface of the carriage main body 20 and a second state in which they are positioned away from the upper surface of the carriage main body 20. The mounting portions 80a, 80b are arranged horizontally in the left-right direction. The mounting portions 80a, 80b are long, straight rods, and may be, for example, hollow pipes made of aluminum alloy and having a substantially rectangular cross section. The left-right length of each of the mounting portions 80a, 80b is shorter than the left-right length of the carriage main body 20.

[0048] First, the placement sections 80a and 80b in the first state will be described. In the first state, the placement sections 80a and 80b are located on the upper surface of the cart main body 20 and are spaced apart in the front and rear. Therefore, it is possible to place an object to be transported straddling the placement sections 80a and 80b. In this embodiment, the placement sections 80a and 80b in the first state are located approximately symmetrically with respect to the center line C2 and have an approximately symmetrical configuration, so the placement section 80a will be mainly described, and a description of the placement section 80b will be omitted as appropriate.

[0049] The mounting portion 80a is located on the front side of the bogie main body 20, and is located closer to the front end of the bogie main body 20 than the center line C2. Furthermore, the mounting portion 80a overlaps with the area of ​​the bogie main body 20 in a plan view, and is located so as not to protrude from the area of ​​the bogie main body 20 in a plan view. Here, the area of ​​the bogie main body 20 refers to the range inside the outer periphery of the bogie main body 20 in a plan view.

[0050] The mounting portion 80a is in surface contact with the upper surfaces of the reinforcing frames 26a and 26d, and the load from the transported object is transmitted to the reinforcing frames 26a and 26d. Furthermore, the mounting portion 80a overlaps with the components that make up the bogie body 20 in a plan view. Specifically, the mounting portion 80a overlaps with parts of the reinforcing frames 26a and 26d in a plan view, and also overlaps with part of the mounting member 31A. Furthermore, the mounting portion 80a is positioned so as to cover parts of the front spaces 27a and 27d from above. In the first state, the upper surface of the mounting portion 80a is a flat mounting surface 81 on which the transported object is placed.

[0051] In the first state, the transport cart 10 has a space S1 above the cart body 20, between the mounting portions 80a and 80b. The space S1 opens upward in a side view. A pair of claws of a forklift can be inserted into the space S1. The height H1 of the space S1 is approximately the same as the vertical height of the mounting portions 80a and 80b in the first state. The height H1 of the space S1 in this embodiment is set to be larger than the thickness T of the claws of the forklift. Furthermore, the length L1 of the space S1 in the front-rear direction is longer than half the length of the cart body 20 in the front-rear direction. The length L1 of the space S1 in this embodiment is set to be longer than the distance between the pair of claws of the forklift.

[0052] Next, the placement units 80a and 80b in the second state will be described. In the second state, the placement units 80a and 80b are positioned away from the upper surface of the carriage main body 20. In this embodiment, the placement units 80a and 80b in the second state are positioned approximately symmetrically with respect to the center line C2 and have an approximately symmetrical configuration, so the placement unit 80a will be mainly described, and a description of the placement unit 80b will be omitted as appropriate.

[0053] The placement portion 80a transitions from the first state to the second state by rotating relative to the carriage main body portion 20, specifically the reinforcing portion 25. The mounting portion 80a is rotatably connected to the reinforcing frame portion 26a adjacent to the front frame portion 21a via a hinge portion 82. The hinge portion 82 is attached so as to straddle the rear surface of the mounting portion 80a in the first state and the rear surface of the reinforcing frame portion 26a. The rotation axis of the hinge portion 82 is arranged so that its axial direction is along the left-right direction. The axis U of the rotation axis of the hinge portion 82 is located at the rear end and upper end of the reinforcing frame portion 26a. When the mounting portion 80a rotates approximately 180° from the first state via the hinge portion 82, the mounting portion 80a is positioned between the reinforcing frame portions 26a and 26b, in the space 27c of the bogie main body portion 20. The mounting portion 80a overlaps with the area of ​​the bogie main body portion 20 in a plan view, and is positioned so as not to protrude from the area of ​​the bogie main body portion 20 in a plan view. However, since the mounting portion 80a is located within the space 27c, it does not overlap with either of the mounting members 31A and 31B in plan view. In addition, in the second state, the mounting surface 81, which was located on the upper surface in the first state, is located on the lower surface.

[0054] The mounting portion 80a in the second state is positioned so as not to protrude above the upper surface of the bogie main body 20, and so as not to protrude below the lower surface of the bogie main body 20. The upper surface of the mounting portion 80a in the second state may be substantially flush with the upper surface of the bogie main body 20, or may be lower than the upper surface of the bogie main body 20. Furthermore, the lower surface of the mounting portion 80a in the second state may be substantially flush with the lower surface of the bogie main body 20, or may be higher than the lower surface of the bogie main body 20.

[0055] In the second state, the transport cart 10 can be configured so that the upper surface of the cart body 20 is flatter than in the first state. By making the upper surface of the cart body 20 flat in this way, even transported objects that cannot be placed on the placement sections 80a, 80b in the first state or that are difficult to place can be easily placed on the placement sections 80a, 80b.

[0056] In the transport platform 10 configured as described above, a forklift can lift only the transported article placed between the placement sections 80a and 80b in the first state. Furthermore, in the transport platform 10, regardless of whether the placement sections 80a and 80b are in the first state or the second state, the transport platform 10 itself (together with the transport platform 10) can be lifted by a forklift. The forklift may be one that is operated by an operator, or may be an AGF (Automated Guided Forklift) that operates unmanned without operator operation.

[0057] First, a case where only the transported object is lifted by a forklift will be described. Fig. 8 is a side view showing an example of a state in which a plurality of flat plasterboards P are stacked and placed as transported items on the cart body 20. In Fig. 8, a plane F obtained by extending the placement surfaces 81 of the placement sections 80a and 80b in the horizontal direction is shown by a two-dot chain line.

[0058] Here, multiple plasterboards P are placed on the placement sections 80a and 80b, straddling the two sections. When lifting only the transported object with a forklift, a pair of claws of the forklift are inserted from the side of the transport cart 10 into the space S1 located between the placement sections 80a and 80b. At this time, since no parts of the transport cart 10 are arranged in the space S1 from the right frame section 21c to the left frame section 21d in a side view, the claws inserted into the space S1 do not come into contact with the parts of the transport cart 10. A pair of forklift tines is inserted into space S1 and then raised. Since space S1 is open at the top, the raised tines support only the transported object. Therefore, by raising the forklift tines, only the transported object can be lifted.

[0059] Next, a case where the transport cart 10 itself is lifted by a forklift will be described. In a side view, the transport cart 10 has spaces S2 below the cart body 20, between the front caster 41A and the central caster 41B, and between the rear caster 41A and the central caster 41B. The tines of a forklift can be inserted into each of the spaces S2. The height H2 of the space S2 is set to be larger than the thickness of the tines of the forklift. Furthermore, the length L2 of the space S2 in the front-to-rear direction is set to be larger than the width of one tine of the forklift.

[0060] Therefore, when lifting the transport cart 10 itself with a forklift, a pair of forklift claws is inserted from the sides of the transport cart 10 into the spaces S2 located at the front and rear, respectively. With the forklift claws inserted into the spaces S2, the pair of claws is raised. Because the right frame portion 21c and the left frame portion 21d of the cart main body 20 are located above the space S2, the raised claws support the undersides of the right frame portion 21c and the left frame portion 21d. Therefore, by raising the forklift claws, the entire transport cart 10 can be lifted.

[0061] Here, the space S1 and the space S2 are located above and below the cart body 20. Therefore, whether lifting only the transported object or lifting the entire transport cart 10, there is no need to adjust the distance between the pair of claws. The length L2 of the space S2 varies as the casters 41A, 41B rotate. If the length L2 of the space S2 is short, the forklift claws may come into contact with the casters 41A, 41B when they are inserted into the space S2, resulting in damage. Furthermore, when the transport cart 10 itself is being lifted by the forklift, if the casters 41A, 41B rotate, the casters 41A, 41B may come into contact with the claws or surrounding objects, resulting in damage.

[0062] Therefore, in this embodiment, the rotation of the casters 41A, 41B is locked by the rotation lock mechanism 100 provided on the casters 41A, 41B, and then the forklift claws are inserted into the space S2 or the transport cart 10 itself is lifted by the forklift. FIG. 9 is a bottom view of the transport cart 10, showing a state in which the rotation of the casters 41A and 41B is locked by the rotation lock mechanism 100. As shown in FIG.

[0063] The rotation of the casters 41A at the four corners is locked when the operating pieces 55b of the casters 41A overlap the corner members 22 in a plan view or a bottom view. The rotation position of the casters 41A at this time is a state in which the operating pieces 55b of the casters 41A do not protrude from the outer shape of the cart main body 20 in a plan view or a bottom view, or protrude only slightly. Specifically, in the case of the two rear casters 41A, the rotation of the casters 41A is locked when the wheels 42 are rotated 45° from a state in which they are facing forward and backward, and are facing diagonally. In addition, in the case of the two front casters 41A, the rotation of the casters 41A is locked when the wheels 42 are rotated 135° from a state in which they are facing forward and backward, and are facing diagonally. The position in which the rotation of the casters 41A is locked is a state in which the rear ends of the wheels 42 are facing the corners of the cart main body 20 in a plan view or a bottom view.

[0064] On the other hand, the central caster 41B is locked at a position where the length L2 of the space S2 can be secured long in a side view. Specifically, the rotation of the caster 41B is locked when the wheel 42 is rotated 90° from a position facing the front-rear direction to a position facing the left-right direction. The position where the rotation of the caster 41B is locked is when the rear end of the wheel 42 faces the center of the cart main body 20 in a plan view or a bottom view. When viewed along the axial direction of the axle 43, the caster 41B is positioned so that the rear end of the wheel 42 is offset away from the swivel axis O2. Therefore, by orienting the rear end of the wheel 42 toward the center of the cart main body 20, the caster 41B can be locked so that it does not protrude from the outer shape of the cart main body 20, or so that the protrusion is minimal.

[0065] The locked portions 132 of the swivel locking mechanisms 100 for the casters 41A and 41B are arranged so as to be able to lock the casters 41A and 41B at their respective swivel positions as shown in FIG. 2, the locked portions 132 of the two front casters 41A are located closer to the center line C1 and further rearward than the swivel axis O1, at a 45° angle from the swivel axis O1. Similarly, the locked portions 132 of the two rear casters 41A are located closer to the center line C1 and further frontward than the swivel axis O1, at a 45° angle from the swivel axis O1. That is, the locked portions 132 of the casters 41A are disposed at a position where the acute angle α between the center line S of the width of the locked portions 132 and the center line C1 of the cart main body 20 intersects at approximately 45°. The locked portions 132 of the two central casters 41B are located on the opposite side of the center line C1 across the rotation axis O2, and the center line S of the width of the locked portions 132 overlaps with the center line C2.

[0066] The operation by the user to lock the rotation of the casters 41A and 41B will now be described. Figure 10(a) is an oblique view showing the state of the swivel lock mechanism 100 when the rotation of the casters 41A and 41B is not locked, and Figure 10(b) is an oblique view showing the state of the swivel lock mechanism 100 when the rotation of the casters 41A and 41B is locked. Fig. 11(a) is a cross-sectional view showing the state of the swivel lock mechanism 100 when the swivel of the casters 41A, 41B is not locked, and Fig. 11(b) is a cross-sectional view showing the state of the swivel lock mechanism 100 when the swivel of the casters 41A, 41B is locked. Figs. 11(a) and 11(b) are cross-sectional views taken along a line passing through the center line S of the width of the swivel axes O1, O2 and the locked portion 132.

[0067] 10(a) and 11(a), when the rotation of casters 41A, 41B is not locked, locking portion 124 of locking member 120 and locked portion 132 of locked member 130 are separated, and the engagement between locking portion 124 and locked portion 132 is released. Therefore, fork member 46a can freely rotate about rotation axes O1, O2. At this time, shaft member 115 is engaged with first positioning portion 123a of locking member 120, so the position of locking member 120 is maintained.

[0068] When a user wants to lock the rotation of casters 41A, 41B, casters 41A, 41B are rotated so that locking portion 124 of locking member 120 faces locked portion 132 of locked member 130, as shown in Figures 10(a) and 11(a). Next, the user presses the locking portion 124 toward the pivot axes O1 and O2, for example, using their feet. At this time, the shaft member 115, biased by the biasing member 116, engages with the first positioning portion 123a of the locking member 120, so the user presses the locking portion 124 against the biasing force of the biasing member 116. Therefore, the locking member 120 rotates around the shaft member 114 in the direction of arrow A, and the locking portion 124 engages with the locked portion 132, as shown in FIGS. 10(b) and 11(b). Furthermore, as the locking member 120 rotates, the shaft member 115 moves within the elongated hole, climbing over the protrusion at the boundary between the first positioning portion 123a and the second positioning portion 123b, and engaging with the second positioning portion 123b. Therefore, the position of the locking member 120 is maintained by the engagement of the shaft member 115 with the second positioning portion 123b.

[0069] By engaging the locking portion 124 with the locked portion 132, even if an attempt is made to rotate the casters 41A, 41B, the locking portion 124 interferes with the locked portion 132 and the casters 41A, 41B cannot move, so the rotation of the casters 41A, 41B can be locked. Note that the user may also use the operating portion 125 to engage the locking portion 124 with the locked portion 132.

[0070] In this way, by locking the rotation of the casters 41A, 41B, the length L2 of the space S2 can be maintained in an extended state, which prevents the forklift claws from coming into contact with the casters 41A, 41B when the forklift claws are inserted into the space S2. Also, when the transport cart 10 itself is being lifted by the forklift, the casters 41A, 41B can be prevented from rotating and coming into contact with the claws or surrounding objects.

[0071] When a user unlocks the rotation of casters 41A and 41B, the user presses operating unit 125 toward rotation axes O1 and O2, for example, using their foot. At this time, because shaft member 115, biased by biasing member 116, is engaged with second positioning portion 123b of locking member 120, the user presses operating unit 125 against the biasing force of biasing member 116. Therefore, locking member 120 rotates around shaft member 114 in the direction of arrow B, disengaging locking portion 124 from locked portion 132. Furthermore, as locking member 120 rotates, shaft member 115 moves within the elongated hole, overcomes the protrusion at the boundary between first positioning portion 123a and second positioning portion 123b, and engages with first positioning portion 123a. Therefore, the position of locking member 120 is maintained by the engagement of shaft member 115 with first positioning portion 123a. By releasing the engagement between the locking portion 124 and the locked portion 132, the locking portion 124 does not interfere with the locked portion 132 when the casters 41A, 41B are rotated, and therefore the rotation lock mechanism 100 can release the lock on the rotation of the casters 41A, 41B. Therefore, the casters 41A, 41B can freely rotate around the rotation axes O1, O2.

[0072] The above-described transport carts 10 can be stacked. 12 is a diagram showing two transport carts 10 stacked on top of each other. Multiple transport carts 10 may be stacked when storing the transport carts 10 without using them or when transporting the transport carts 10 themselves to and from a work site. In this case, the casters 41A, 41B of the upper transport cart 10 are placed on the mounting members 31A, 31B of the lower transport cart 10, respectively, thereby reducing the overall height of the stacked transport carts 10.

[0073] As described above, the transporter cart 10 of this embodiment includes the first mounting portion 80a and the second mounting portion 80b located apart in the front-to-rear direction of the cart main body 20. The first mounting portion 80a and the second mounting portion 80b can transition between a first state in which they are located on the upper surface of the cart main body 20 and a second state in which they are spaced apart from the upper surface of the cart main body 20. In the first state and the second state, the first mounting portion 80a and the second mounting portion 80b overlap with the area of ​​the cart main body 20 in a plan view, which makes it possible to prevent the transporter cart 10 from becoming too large.

[0074] Furthermore, since the casters 41A, 41B of this embodiment have a swivel lock mechanism 100 that locks the swivel of the casters 41A, 41B, the swivel of the casters 41A, 41B can be locked. Note that the lock member 120 that locks the swivel of the casters 41A, 41B and the brake pedal 55 that holds the wheels 42 of the casters 41A, 41B in a state where they cannot rotate can be operated independently. Therefore, the swivel of the casters 41A, 41B can be locked while the wheels 42 of the casters 41A, 41B can rotate, or the wheels 42 of the casters 41A, 41B can be made to be in a state where they cannot rotate while the swivel of the casters 41A, 41B is not locked.

[0075] In this embodiment, the case where the casters 41A and 41B have the swivel lock mechanism 100 has been described, but they may not have the swivel lock mechanism 100. Also, the caster 41B may not have the swivel lock mechanism 100, and the caster 41A may have the swivel lock mechanism 100, or the caster 41A may not have the swivel lock mechanism 100, and the caster 41B may have the swivel lock mechanism 100.

[0076] <Second embodiment> In the second embodiment, a transport cart 210 will be described in which the two central casters 41B of the transport cart 10 of the first embodiment are omitted, and four casters 41A are arranged on the underside of the cart main body 20. Note that the same components as those in the first embodiment are given the same reference numerals and their description will be omitted.

[0077] Fig. 13 is a perspective view showing an example of the configuration of the transport cart 210. Fig. 14 is a bottom view showing an example of the configuration of the transport cart 210. Fig. 15 is a plan view showing an example of the configuration of the transport cart 210. The mounting section 230 of the transporter cart 210 has a plurality of (four) mounting members 31A but does not have a mounting member 31B. Furthermore, the running section 240 of the transporter cart 210 has a plurality of (four) casters 41A arranged at the four corners of the cart main body 220 but does not have the two central casters 41B. Therefore, in a side view, the transporter cart 210 has a large space S3 below the cart main body 220 between the front caster 41A and the rear caster 41A (see FIG. 13).

[0078] As described above, the transport cart 210 of this embodiment does not have the two central casters 41B, and therefore the automated guided vehicle V can enter the space S3 below the cart main body 220 from the side. In other words, the transport cart 210 can be transported by the automated guided vehicle V. The automated guided vehicle V is a transport car that can travel automatically without human driving operation. The automated guided vehicle V is assumed to be an automated guided vehicle that enters below the cart main body 220 from the side and transports the transport cart 210 in a lifted-up state, but it may also be an automated guided vehicle that transports the transport cart 210 with the casters 41A in contact with the traveling surface without being lifted up.

[0079] In this embodiment, the user can lock the rotation of the caster 41A in advance using the rotation lock mechanism 100, thereby preventing the caster 41A from rotating due to centrifugal force or the like when the automated guided vehicle V transports the transport cart 210. Note that, in this embodiment, the case where the caster 41A has the rotation lock mechanism 100 has been described, but the rotation lock mechanism 100 does not have to be provided.

[0080] <Third embodiment> In the first embodiment, the locked member 130 is described as being in the shape of a substantially flat disk. In the third embodiment, the locked member 140 is described as being in the shape of an uneven disk. Fig. 16 is a perspective view showing a state before the caster 41A is coupled to the mounting member 31A. Note that in Fig. 16, the configuration is the same as in the first embodiment except for the locked member 140, and the same reference numerals are used and the description thereof will be omitted.

[0081] The locked member 140 has a central insertion hole 141 that is coaxial with the pivot axis O1. The locked member 140 has lower convex portions that are convex toward the bottom and upper convex portions that are convex toward the top, which are formed alternately along the circumferential direction around the pivot axis O1. By having the lower convex portions and upper convex portions in this way, the rigidity of the locked member 140 can be increased. The locked member 140 also has a locked portion 142 on part of its outer periphery. The locked portion 142 engages with the locking portion 124 of the locking member 120. When connecting the fork member 46 of the caster 41A to the mounting member 31A, the lockable member 140 is positioned between the fork member 46 (specifically, the upper tray member 47) and the mounting member 31A. At this time, the lower convex portion of the lockable member 140 contacts the upper tray member 47, and the upper convex portion contacts the mounting member 31A. Therefore, when the wheel 42 of the caster 41A collides with an obstacle, the moment generated in the caster 41A is transmitted to the highly strong mounting member 31A via the rigid lockable member 140, thereby preventing plastic deformation of the fork member 46 of the caster 41A.

[0082] <Fourth embodiment> In the first embodiment, the mounting portions 80a and 80b are described as being positioned so as to rest on the upper sides of the reinforcing frame portions 26a and 26d. In the fourth embodiment, the mounting portions 380a and 380b are described as being positioned in different positions.

[0083] FIG. 17 is a side view showing an example of the configuration of a transporter cart 310 according to the fourth embodiment. Similarly, the mounting portions 380a and 380b of this embodiment can transition between a first state in which they are located on the upper surface of the carriage main body 320 and a second state in which they are located away from the upper surface of the carriage main body 320. Meanwhile, the mounting portions 380a and 380b of this embodiment are rotatably connected to the reinforcing frame portion 26b via hinge portions 82.

[0084] In the first state, the mounting portions 380a, 380b are in surface contact with the upper surfaces of the reinforcing frame portions 26b, 26e, and the load from the transported object is transmitted to the reinforcing frame portions 26b, 26e. Meanwhile, in the second state, the mounting portions 380a, 380b rotate approximately 180° from the first state via the hinge portions 82, and the mounting portions 380a, 380b transition to the second state in which they are located between the reinforcing frame portions 26a and 26b.

[0085] In this embodiment, since the distance between the placement sections 380a and 380b in the first state can be made small, even an object that is short in the front-to-rear direction can be placed on it. In this embodiment, when lifting only the object placed between the placement sections 380a and 380b in the first state with a forklift, one claw of the forklift can be inserted into the front side of the placement section 380a from the side of the transport cart 310, and the other claw can be inserted from the rear side of the placement section 380b, thereby lifting only the object.

[0086] The present invention has been described above using the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, and modifications can be made within the scope of the present invention by combining part of each embodiment or part of each of the following variations with other embodiments or other variations.

[0087] In the present embodiment, the casters 41A, 41B are described as being configured such that the swivel lock mechanism 100 locks the swivel at one predetermined swivel position, but the present invention is not limited to this, and the swivel may be locked at a plurality of predetermined swivel positions. In this case, the locked member 130 can be realized by providing a plurality of locked portions 132 spaced apart in the circumferential direction.

[0088] In the present embodiment, the case where the swivel lock mechanism 100 locks the swivel of the casters 41A, 41B at the swivel position described above has been described, but this is not the only possible case. The swivel lock mechanism 100 may be configured to lock the swivel of the casters 41A, 41B at a swivel position where the wheels 42 face forward and backward (for example, the state shown in FIG. 2). In this embodiment, the caster 41B has been described as being in a position where the rear end of the wheel 42 faces the center of the cart main body 20, and the swivel lock mechanism 100 locks the rotation. However, the swivel lock mechanism 100 may be configured to lock the rotation at a position where the rear end of the wheel 42 faces the opposite side from the center of the cart main body 20.

[0089] In this embodiment, the case has been described where the rotation lock mechanism 100 locks the rotation of the casters 41A and 41B at a predetermined rotation position, but the rotation position may be any position. 9, the swivel lock mechanism 100 may be configured to lock the rear end of the wheel 42 of the caster 41A at any position within an angle range β1, any position within an angle range β2, any position within an angle range β3, or any position within an angle range β4 around the swivel axis O1. The swivel lock mechanism 100 may also be configured to lock the rear end of the wheel 42 of the caster 41A at a position where it overlaps with the boundary line between the angle ranges β1 and β2, a position where it overlaps with the boundary line between the angle ranges β2 and β3, a position where it overlaps with the boundary line between the angle ranges β3 and β4, or a position where it overlaps with the boundary line between the angle ranges β4 and β1. 9, the swivel lock mechanism 100 may be configured to lock the rear end of the wheel 42 of the caster 41B at any position within an angle range γ1, any position within an angle range γ2, any position within an angle range γ3, or any position within an angle range γ4 around the swivel axis O2. The swivel lock mechanism 100 may also be configured to lock the rear end of the wheel 42 of the caster 41B at a position where it overlaps with the boundary line between the angle ranges γ1 and γ2, a position where it overlaps with the boundary line between the angle ranges γ2 and γ3, a position where it overlaps with the boundary line between the angle ranges γ3 and γ4, or a position where it overlaps with the boundary line between the angle ranges γ4 and γ1.

[0090] In this embodiment, the case where the support member 110 and the locking member 120 are located on the fork member 46 side and the locked member 130 is located on the trolley main body 20 side has been described, but this is not limited to this case, and the support member 110 and the locking member 120 may be located on the trolley main body 20 side and the locked member 130 may be located on the fork member 46 side. In this embodiment, the case where the locked member 130 has the locked portion 132 has been described, but this is not limited to this case, and the locked portion 132 may be provided integrally with the mounting members 31A, 31B, or the locked portion 132 may be provided integrally with the bogie main body 20. In this case, the locked member 130 can be omitted.

[0091] In the present embodiment, the transport carts 10, 210, and 310 have been described as having six casters 41A and 41B or four casters 41A, but this is not limited to this. The number of casters 41A and 41B can be freely changed depending on the use of the transport carts 10, 210, and 310. In the present embodiment, the mounting section 30, 230 has been described as having four mounting members 31A and two mounting members 31B or four mounting members 31A, but this is not limited to this. The two front mounting members 31A may be connected to form a single mounting member that is long in the left-right direction. The two rear mounting members 31A may also be connected to form a single mounting member that is long in the left-right direction. The two central mounting members 31B may also be connected to form a single mounting member that is long in the left-right direction.

[0092] In this embodiment, the case where the transport cart 10 has the mounting portions 80a and 80b and the transport cart 310 has the mounting portions 380a and 380b has been described, but this is not limited to this. The transport cart may be configured to have the mounting portions 80a and 380b, or may be configured to have the mounting portions 380a and 80b. [Explanation of symbols]

[0093] 10, 210, 310: Transport cart 20, 220, 320: Cart body 22: Corner member 23: Insertion hole 41A, 41B: Caster 42: Wheel 55: Brake pedal 55b: Operation piece 70: Hand push member 80a, 80b, 380a, 380b: Placement section 100: Swivel lock mechanism 110: Support member 120: Lock member 124: Lock section 125: Operation section 130, 140: Locked member 132, 142: Locked section

Claims

1. A bogie main body; Casters located at four corners of the cart body; A transport cart including a first placement section and a second placement section positioned apart in the front-rear direction of the cart body, The first placement unit and the second placement unit are A transport trolley capable of transitioning between a first state in which it is located on the top surface of the trolley main body and a second state in which it is separated from the top surface of the trolley main body, and characterized in that in the first and second states it overlaps with the area of ​​the trolley main body in a planar view.

2. 2. The transporting cart according to claim 1, wherein in the first state, a pair of claws of a forklift can be inserted between the first placement portion and the second placement portion.

3. The first placement unit and the second placement unit are 3. The transporting cart according to claim 1, wherein the support members are positioned apart from each other across a center line of the cart body, which is perpendicular to the front-rear direction in a plan view.

4. The first placement unit and the second placement unit are 4. The transporting cart according to claim 3, wherein the two carts are positioned approximately symmetrically with each other in front and behind the center line in a plan view.

5. The cart body has an attachment member that attaches the caster to a lower surface of the cart body, The first placement unit and the second placement unit are 3. The transporting cart according to claim 1, wherein in the first state, the transporting cart overlaps with the mounting member in a plan view.

6. The first placement unit and the second placement unit are The transporting cart according to claim 5, wherein in the second state, the transporting cart does not overlap with the mounting member in a plan view.

7. The first placement unit and the second placement unit are The transporting cart according to claim 1 or 2, characterized in that the transporting cart can transition between the first state and the second state by rotating with respect to the cart body.

8. The first placement unit and the second placement unit are 3. The transporting cart according to claim 1, wherein in the second state, the upper surface is positioned so as not to protrude upward from the upper surface of the cart body.

9. 3. The transport cart according to claim 1, wherein the caster has a swivel lock mechanism for locking the swivel.

10. The caster has a wheel, The rotation lock mechanism is 10. The transport truck according to claim 9, wherein the rotation of the caster can be locked when the rear end of the wheel is facing a corner of the truck body in a plan view.

11. In addition to the casters located at the four corners, a caster is provided on the center side in the front-rear direction of the cart body, 3. The transport cart according to claim 1, wherein the caster on the central side has a swivel lock mechanism for locking the swivel.

12. The central caster has a wheel, The rotation lock mechanism is A transport cart as described in claim 11, characterized in that the rotation of the central caster can be locked when, when viewed in a plan view, the rear end of the wheel is facing toward the center of the cart main body or when it is facing away from the center of the cart main body.

Images