Transport carriage

Abstract

To provide a carrying truck capable of preventing inclination.SOLUTION: This carrying truck 10 includes a truck body part 20 for loading a carrying object, a caster 31A arranged in at least four corners of the truck body part 20, and an auxiliary caster 51 positioned outside of an outer peripheral edge of the truck body part 20. The carriage 10 includes a connection part 60 for connecting the auxiliary caster 51 to the carriage body part 20.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 items at work sites, etc. The transport cart has casters attached to the four corners of the underside of the cart body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-46379 Summary of the Invention [Problem to be solved by the invention]

[0004] When such a transport cart is loaded with transported goods, the center of gravity becomes high and there is a risk of the cart tipping over. The present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a transport cart that can be prevented from tipping over. [Means for solving the problem]

[0005] The transport cart of the present invention is characterized by comprising a cart main body for carrying transported items, casters arranged at at least four corners of the cart main body, and a ground contact portion located outside the outer periphery of the cart main body. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a transport cart that can be prevented from tipping over. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view of a transport cart according to a first embodiment. [Figure 2]FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. [Figure 6] FIG. 2 is an exploded perspective view of the ground unit. [Figure 7] FIG. 2 is a diagram showing the configuration of a grounding unit. [Figure 8] FIG. 1 is a front view showing two transport carts stacked on top of each other. [Figure 9] FIG. 10 is a bottom view of the transport cart according to the second embodiment. [Figure 10] FIG. 10 is a perspective view of a transport cart according to a third embodiment. [Figure 11] FIG. 10 is a perspective view of a transport cart according to a fourth embodiment. [Figure 12] FIG. 10 is a perspective view of a transport cart according to a fifth embodiment. [Figure 13] FIG. 10 is a perspective view of a transport cart according to a sixth embodiment. [Figure 14] FIG. 13 is a perspective view of a transport cart according to a seventh embodiment. [Figure 15] FIG. 13 is a bottom view of the transport cart according to the eighth embodiment. [Figure 16] FIG. 13 is a bottom view of the transport cart according to the ninth embodiment. [Figure 17] FIG. 20 is a bottom view of the transport cart according to the tenth embodiment. [Figure 18] FIG. 23 is a bottom view of the transport cart according to the eleventh embodiment. [Figure 19] FIG. 23 is a bottom view of the transport cart according to the twelfth embodiment. [Figure 20] FIG. 23 is a bottom view of the transport cart according to the thirteenth embodiment. [Figure 21] FIG. 22 is a bottom view of the transport cart according to the fourteenth embodiment. [Figure 22] FIG. [Figure 23] FIG. [Figure 24] FIG. [Figure 25] FIG. [Figure 26] FIG. 23 is a diagram showing the configuration of a grounding unit according to a fifteenth 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 of a transporter cart 10 according to the first embodiment. Fig. 2 is a bottom view of the transporter cart 10. Fig. 3 is a plan view of the transporter cart 10. Fig. 4 is a front view of the transporter cart 10. Fig. 5 is a side view of the transporter cart 10. For convenience, in the following drawings, arrow Fr indicates the front side, arrow Rr indicates the rear side, arrow R indicates the right side, and arrow L indicates the left side. However, the transport vehicle 10 can travel in any direction on the travel surface, forward, backward, left, or right. Furthermore, center line C is the center of the length of the transport vehicle 10 in the left-right direction.

[0009] The transport cart 10 includes a cart body 20, a running section 30, a push member 40, and a ground contact unit 50. First, the carriage main body 20 will be described. The carriage body 20 is formed by connecting a plurality of frame sections and the like, and is used to carry transported objects. In a plan view, the carriage body 20 is substantially rectangular, with the longitudinal direction being the front-to-rear direction and the transverse direction being the left-to-right direction. The carriage body 20 has a front frame section 21a, a rear frame section 21b, a right frame section 21c, a left frame section 21d, corner members 22, reinforcing frame sections (reinforcing sections) 25a to 25d, a mounting section 27, and guide sections 28A and 28B.

[0010] The front frame portion 21a, the rear frame portion 21b, the right frame portion 21c, and the left frame portion 21d constitute the outer shape of the bogie main body portion 20. The front frame portion 21a and the rear frame portion 21b correspond to an example of a pair of opposing frame portions. The right frame portion 21c and the left frame portion 21d correspond to an example of a pair of opposing frame portions. 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 an aluminum alloy.

[0011] The corner member 22 is made of an aluminum alloy, for example, formed by extrusion molding. The corner member 22 has an insertion hole 23 that opens to the top and a stopper portion 24 that closes the bottom. A push member 40 can be inserted into the insertion hole 23 of the corner member 22. The lower end of the push member 40 inserted into the insertion hole 23 is supported by the stopper portion 24.

[0012] 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 rectangular four-sided frame. The inside of the frame is reinforced by a plurality of reinforcing frame portions 25a, 25b, 25c, and 25d that are butted together in the front-rear and left-right directions and joined with screws, rivets, welding, or the like. The reinforcing frame portions 25a, 25b, 25c, and 25d may be, for example, rectangular hollow pipes made of aluminum alloy or plates with an irregular cross section. Here, by joining two reinforcing frame portions 25a and 25b that are long in the front-rear direction to twelve reinforcing frame portions 25c that are short in the left-right direction, a plurality of rectangular spaces 26 are formed that are divided into three rows in the front-rear direction and five rows in the left-right direction in a plan view. Further, in the front and rear spaces 26 sandwiching the central space 26 of the two rows of spaces 26 on the left and right sides, reinforcing frame portions 25d are joined to the front and rear reinforcing frame portions 25c so as to cross the spaces 26 from front to back. Furthermore, the carriage body 20 has a mounting portion 27 attached to the upper portion of each of the spaces 26 that are not blocked by mounting members 32A and 32B (described later). The mounting portion 27 is a flat metal plate on which an object to be transported is placed. The mounting portion 27 is connected to each frame portion and each reinforcing frame portion with rivets or screws. When identical carriages 10 are stacked, portions of casters 31A and 31B (described later) of the upper carriage 10 fit into the spaces 26 that are not blocked by the mounting portion 27, i.e., the spaces 26 that are open at the top.

[0013] The guide portions 28A and 28B guide the sliding of a connecting member 61 (described later) of the ground unit 50. The guide portions 28A and 28B have a length shorter than the left-right length of the bogie body 20. The guide portions 28A and 28B are hollow members with a substantially rectangular cross section, and both ends are open. The guide portions 28A and 28B may be, for example, rectangular hollow pipes made of an aluminum alloy. The guide portion 28A is located between the two front casters 31A and the two central casters 31B, and the guide portion 28B is located between the two rear casters 31A and the two central casters 31B. The guide portions 28A and 28B are located so as to straddle two reinforcing frame portions 25d located apart on the left and right, and are connected to the undersides of the reinforcing frame portions 25a, 25b, and 25c with rivets or screws.

[0014] Next, the running unit 30 will be described. The running section 30 runs on the running surface while supporting the load of the carriage body 20 and the transported object. The running unit 30 has a plurality of casters 31A, 31B. As shown in FIG. 2, the running unit 30 has six casters: four casters 31A arranged at the four corners of the carriage body 20 and two casters 31B arranged at the center in the front-to-rear direction and spaced apart on the left and right. The casters 31A, 31B are attached to the carriage body 20 via mounting members 32A, 32B connected to the respective frame portions and reinforcing frame portions in a manner that closes the space 26 from below. The casters 31A, 31B are rotatable about a rotation axis O1 that extends in the up-down direction.

[0015] Here, the casters 31A located at the four corners are brake-equipped casters that can be braked or released in response to user operation. On the other hand, the caster 31B located in the center is a brakeless caster. The configuration of the caster 31A will be described below. Note that the caster 31B is configured such that the brake function is omitted from the caster 31A, and a detailed description thereof will be omitted.

[0016] As shown in FIG. 5, the caster 31A includes a wheel 33, a support portion 34, a brake pedal 37, and a swivel portion 39. The wheel 33 has a wheel portion with a built-in bearing and a tire portion fitted onto the outer periphery of the wheel portion.

[0017] The support portion 34 rotatably supports the wheel 33 via an axle. The support portion 34 has a fork member 35 that supports the wheel 33, and a pedal holding member 36 that holds the brake pedal 37 so that it can swing. Fork member 35 is formed, for example, by press-forming a steel plate. Fork member 35 is integrally formed with a pair of side walls located on both sides of wheel 33 and a circular top plate that connects the pair of side walls above wheel 33. The top plate is held rotatably by a swivel part 39. The pedal holding member 36 is formed, for example, by press-forming a steel plate. The pedal holding member 36 is located on both sides of the wheel 33 and is integrally formed with a pair of side walls fixed to the fork member 35 and a connecting plate connecting the pair of side walls at the upper side.

[0018] The brake pedal 37 is formed, for example, by press-forming a steel plate. The brake pedal 37 can swing up and down relative to the pedal holding member 36. The brake pedal 37 has an operating part 38. The operating part 38 is substantially plate-shaped, and the user operates the brake pedal 37 to swing up and down with their foot or the like.

[0019] When the brake is released, the brake pedal 37 is in a raised position. On the other hand, when the user presses the operating part 38 of the brake pedal 37 downward with their foot, the brake pedal 37 swings downward against the bias of the spring. As the brake pedal 37 moves, the brake pedal 37 presses firmly against the outer circumferential surface of the wheel 33, directly or indirectly, preventing the wheel 33 from rotating and placing the brake in an applied state. Furthermore, the brake pedal 37 functions as a stopper because it is maintained in the applied state. The pivoting portion 39 allows the wheel 33, the support portion 34, and the brake pedal 37 to pivot.

[0020] While caster 31A has been described above, caster 31B has a configuration in which the brake-related components of caster 31A are omitted. That is, caster 31B has wheel 33, support portion 34, and swivel portion 39, but does not have brake pedal 37. Therefore, caster 31B can swivel about swivel axis O1 via the top plate of fork member 35, just like caster 31A, but cannot be braked.

[0021] Casters 31A and 31B can be attached to the trolley main body 20 by attaching the swivel portions 39 of casters 31A and 31B configured in this manner to mounting members 32A and 32B, respectively, and then attaching the mounting members 32A and 32B to which casters 31A and 31B are attached, respectively, to predetermined positions on the trolley main body 20 with rivets or screws. The casters 31A and 31B are set such that the ground contact position of the wheels 33 and the rotation axis O1 are eccentric in a plan view. Therefore, the casters 31A and 31B rotate around the rotation axis O1 so that the wheels 33 are on the rear side relative to the front side, which is the direction of travel. In FIG. 2, the locus T1 of the component (brake pedal 37) of the caster 31A that is farthest from the pivot axis O1 when the caster 31A pivots around the pivot axis O1 is indicated by a two-dot chain line.

[0022] Next, the push member 40 will be described. The push member 40 is a member that the user holds onto when moving the transport cart 10. The user moves the transport cart 10 by gripping the push member 40 with their hands and pushing or pulling it. The push member 40 is attached to the cart main body 20 by inserting its lower end into the insertion hole 23 of the corner member 22. The transport cart 10 has four push members 40, which are inserted into the insertion holes 23 of the corner members 22. All four push members 40 have approximately the same configuration. However, the number of push members 40 is not limited to four, and one, two, or three push members 40 may be attached. The push members 40 can be removed from the cart main body 20 by pulling them out of the insertion holes 23 of the corner members 22.

[0023] The push member 40 has a main body member 41 as a main body portion, a protective member 43, and a reinforcing member 44. The main body member 41 is a rod-shaped or long, pipe-shaped member. The main body member 41 is made of, for example, an aluminum alloy and is formed by extrusion molding. The main body member 41 has a metallic color such as silver. The inside of the main body member 41 is reinforced in a cross shape to improve its strength.

[0024] The protective member 43 protects the user's hands from coming into contact with surrounding objects when the user grasps the push member 40. The protective member 43 also serves as an indicator of the maximum loading height when loading transported items. The protective member 43 is fixed to the upper side of the main body member 41 at a predetermined distance from the upper end with bolts, rivets, etc. The part of the push member 40 above the protective member 43 functions as a grip portion that the user grasps with their hands. The protective member 43 is disc-shaped and protrudes outward from the outer periphery of the main body member 41, and has a larger outer diameter than the main body member 41.

[0025] The reinforcing member 44 is fixed to the lower end of the main body member 41, specifically at a position close to the lower end, with bolts, rivets, etc. The reinforcing member 44 not only reinforces the strength of the main body member 41 but also suppresses rattle between the main body member 41 and the insertion hole 23 when the main body member 41 is inserted into the insertion hole 23 of the corner member 22. The reinforcing member 44 is made of, for example, an aluminum alloy and is formed by extrusion molding.

[0026] Next, a description will be given of the ground contact unit 50. The ground contact unit 50 functions as an outrigger. The transporter cart 10 of this embodiment has four ground contact units 50a to 50d. Specifically, the transporter cart 10 has two ground contact units 50a and 50b adjacent to the right frame portion 21c, and two ground contact units 50c and 50d adjacent to the left frame portion 21d. The grounding units 50a and 50b are positioned apart in the front-rear direction, and the grounding units 50c and 50d are positioned apart in the front-rear direction. When viewed from the front-rear direction (side view along the front-rear direction), the grounding units 50a and 50b are positioned so as to overlap, and the grounding units 50c and 50d are positioned so as to overlap. Furthermore, the grounding units 50a and 50c are positioned so as to be symmetrical with respect to the center line C, and the grounding units 50b and 50d are positioned so as to be symmetrical with respect to the center line C. When viewed from the left-right direction (side view along the left-right direction), the grounding units 50a and 50c are positioned so as to overlap, and the grounding units 50b and 50d are positioned so as to overlap. The grounding units 50a to 50d have the same configuration, and will be simply referred to as the grounding unit 50 when there is no need to distinguish between them.

[0027] The ground contact unit 50 of this embodiment has an auxiliary caster 51 as a second caster, and a connecting portion 60. The auxiliary caster 51 corresponds to an example of a ground contact portion. The auxiliary casters 51 are positioned outside the outer periphery of the cart main body 20 and are in contact with the running surface (ground surface) to prevent the transport cart 10 from tipping over. In a plan view, the auxiliary casters 51 are positioned so as not to overlap with the cart main body 20. Specifically, the auxiliary casters 51 of the ground contact units 50a and 50b are each positioned to the right of the right frame part 21c, and the auxiliary casters 51 of the ground contact units 50c and 50d are each positioned to the left of the left frame part 21d.

[0028] Fig. 6 is an exploded perspective view of the grounding unit 50. Fig. 7(a) is a view of the grounding unit 50 as seen from the rear with a portion of the grounding unit 50 cut away, and Fig. 7(b) is a bottom view of the grounding unit 50 shown in Fig. 7(a). First, the auxiliary caster 51 will be described. The auxiliary caster 51 can rotate around a rotation axis O2 that is aligned in the vertical direction. The auxiliary caster 51 is a braked caster that can be braked or released in response to a user's operation. The auxiliary caster 51 is a different type of caster from the casters 31A and 31B described above.

[0029] As shown in FIG. 6, the auxiliary caster 51 includes two wheels 53 a and 53 b, a support portion 54 , a brake pedal 57 , and a swivel portion 59 . The two wheels 53a, 53b have an outer diameter smaller than that of the wheels 33 of the casters 31A, 31B. Each of the two wheels 53a, 53b has a wheel portion with a built-in bearing and a tire portion fitted around the outer periphery of the wheel portion. The two wheels 53a, 53b are the same size and are supported in parallel so that they can rotate independently. That is, the wheels 53a and 53b can rotate at different rotational speeds, and the wheel 53a can rotate in one direction while the wheel 53b rotates in the other direction at the same time.

[0030] The support portion 54 rotatably supports the two wheels 53a, 53b and holds the brake pedal 57 so that it can swing. The support portion 54 is formed, for example, by press-forming a steel plate. The support portion 54 is integrally formed with a pair of side walls located on both sides of the wheels 53a, 53b and a circular top plate that connects the pair of side walls above the wheels 53a, 53b. The top plate is held rotatably by a swivel portion 59.

[0031] The brake pedal 57 is operated by the user when the user wishes to brake the auxiliary caster 51. The brake pedal 57 is formed, for example, by press-forming a steel plate. The brake pedal 57 can swing up and down relative to the support part 54. The brake pedal 57 also has an operating part 58. The operating part 58 is substantially plate-shaped, and the user operates the brake pedal 57 to swing up and down with their foot or the like.

[0032] When the brake is released, the brake pedal 57 is in a raised position. Meanwhile, when the user presses the operating portion 58 of the brake pedal 57 downward with their foot, the brake pedal 57 swings downward against the bias of the spring. As the brake pedal 57 swings downward, the brake pedal 57 directly or indirectly presses firmly against the outer circumferential surfaces of the wheels 53a and 53b, preventing the wheels 53a and 53b from rotating and placing the brake in an applied state. Furthermore, the brake pedal 57 functions as a stopper because it is maintained in an applied state. To release the brake from an applied state (stopper state), the user operates the operating portion 58 of the brake pedal 57 upward with their foot, causing the brake pedal 57 to swing upward. As the brake pedal 57 swings upward, the pressure on the wheels 53a and 53b is released, placing the brake in a released state. The rotating portion 59 rotates the wheels 53a and 53b, the support portion 54, and the brake pedal 57.

[0033] The auxiliary caster 51 is set at a position where the ground contact positions of the wheels 53a, 53b and the rotation axis O2 are eccentric in a plan view. Therefore, the auxiliary caster 51 rotates around the rotation axis O2 so that the wheels 53a, 53b are on the rear side relative to the front side, which is the direction of travel.

[0034] Next, the connecting portion 60 will be described. The connecting part 60 connects the auxiliary caster 51 to the cart body 20 so that the auxiliary caster 51 is positioned outside the outer periphery of the cart body 20. The connecting part 60 of this embodiment is able to slide relative to the cart body 20. By sliding the connecting part 60 relative to the cart body 20, the auxiliary caster 51 can be transitioned between a first position positioned outside the outer periphery of the cart body 20 and a second position that is closer to the cart body 20 than the first position.

[0035] As shown in FIG. 6, the connecting portion 60 includes a connecting member 61, an attachment member 63, and a protective member 64. The connecting member 61 connects the auxiliary caster 51 to the carriage body 20. The connecting member 61 is long and has a length that is approximately half the length of the carriage body 20 in the left-right direction. The connecting member 61 is a hollow member with a substantially rectangular cross section, and both ends are open. The connecting member 61 may be, for example, a rectangular hollow pipe made of an aluminum alloy. The auxiliary caster 51 is attached to one end of the connecting member 61 in the longitudinal direction via an attachment member 63. The other end of the connecting member 61 in the longitudinal direction is fitted into the guide portions 28A, 28B, and the connecting member 61 is slidable along the longitudinal direction of the guide portions 28A, 28B. In this embodiment, the connecting member 61 of the grounding unit 50a and the connecting member 61 of the grounding unit 50c are fitted into the same guide portion 28A from opposite sides, and the connecting member 61 of the grounding unit 50b and the connecting member 61 of the grounding unit 50d are fitted into the same guide portion 28B from opposite sides. In addition, a plurality of engagement holes 62a to 62c are formed in the lower wall of the connecting member 61 at intervals in the left-right direction.

[0036] The mounting member 63 mounts the auxiliary caster 51 to the connecting member 61. The mounting member 63 is a member with a roughly U-shaped cross section. The mounting member 63 is formed, for example, by bending a steel plate. The mounting member 63 is integrally formed with a pair of side walls and a connecting wall that connects the pair of side walls at their lower ends. The connecting member 61 is sandwiched from the front and rear by the pair of side walls of the mounting member 63 and fixed with rivets, screws, etc., thereby mounting the mounting member 63. In addition, the auxiliary caster 51 is mounted to the mounting member 63 by threading a bolt protruding upward from the swivel portion 59 into a nut fixed to the connecting wall of the mounting member 63.

[0037] The protective member 64 prevents the connecting member 61 from being damaged by contact with an obstacle. The protective member 64 is a substantially plate-shaped member. The protective member 64 is formed, for example, from a synthetic resin. The protective member 64 is attached to the connecting member 61 by fitting into an opening at one end of the connecting member 61. When the protective member 64 is attached to the connecting member 61, the end of the connecting member 61 and the end of the mounting member 63 are covered from the outside by the protective member 64. Therefore, as shown in FIG. 5 , in a side view, the end of the connecting member 61 and the end of the mounting member 63 are hidden by the protective member 64 and are not visible.

[0038] Furthermore, the bogie main body 20 of this embodiment has stopper portions 80 that stop the sliding of the connecting member 61 so that the connecting member 61 cannot slide freely when the connecting member 61 slides while being guided by the guide portions 28A and 28B. In this embodiment, a stopper portion 80 is attached to each of the four ground contact units 50a to 50d so that the sliding of each of the connecting members 61 can be stopped. Specifically, two stopper portions 80 corresponding to the ground contact units 50a and 50c are attached to the guide portion 28A, and two stopper portions 80 corresponding to the ground contact units 50b and 50d are attached to the guide portion 28B.

[0039] As shown in FIG. 6, the stopper portion 80 includes a housing 81, an engaging member 82, a biasing member 84, and a shaft member 85. The housing 81 supports the engaging member 82 so that it can swing. The housing 81 is a member with a roughly U-shaped cross section. The housing 81 is formed, for example, by bending a steel plate. The housing 81 is integrally formed with a pair of side walls and a connecting wall that connects the pair of side walls at their lower ends. The guide portion 28A is attached to the housing 81 by being sandwiched from the front and rear between the pair of side walls of the housing 81 and fixed with rivets, screws, etc.

[0040] The engaging member 82 advances into the guide portions 28A and 28B and engages with the connecting member 61, thereby stopping the sliding of the connecting member 61. The engaging member 82 then retreats from the guide portions 28A and 28B, disengaging from the connecting member 61 and thereby releasing the stoppage of the sliding of the connecting member 61. The engaging member 82 is a generally block-shaped member that is elongated in the left-right direction. The engaging member 82 is formed, for example, by bending a steel plate. The engaging member 82 is swingable about a shaft member 85 supported by the housing 81, and the end of the engaging member 82 opposite the side where the shaft member 85 is supported is constantly biased upward by a biasing member 84 so as to advance into the guide portions 28A and 28B through a hole 29 formed in the lower wall of the guide portion 28. The engaging member 82 engages with one of the engaging holes 62a to 62c of the connecting member 61, which slides within the guide portions 28A and 28B, preventing the connecting member 61 from freely sliding along the guide portions 28A and 28B.

[0041] Furthermore, engaging member 82 has knob 83 that allows the user to retract engaging member 82 from guide portions 28A and 28B. Knob 83 corresponds to an example of a release portion that releases the stop on sliding of connecting member 61. When the user presses knob 83 downward against the bias of biasing member 84, engaging member 82 swings and retracts from guide portions 28A and 28B. When engaging member 82 retracts, it is disengaged from engaging holes 62a to 62c of connecting member 61, and therefore, while knob 83 is being pressed down, connecting member 61 can slide freely along guide portions 28A and 28B.

[0042] Since the amount by which the connecting member 61 protrudes from the guide portions 28A, 28B varies depending on which of the engaging holes 62a to 62c of the connecting member 61 the engaging member 82 engages with, the user can adjust the amount by which the connecting member 61 protrudes from the guide portions 28A, 28B independently for each of the grounding units 50a to 50d.

[0043] When the engaging member 82 is engaged with the engaging hole 62a, the connecting member 61 protrudes the most from the guide portions 28A and 28B. This state corresponds to the case where the auxiliary caster 51 attached to the connecting member 61 is located at a first position that is outside the outer periphery of the cart main body 20. Note that the connecting member 61 is configured not to protrude further from the guide portions 28A and 28B than the first position by the abutting portion (not shown) of the connecting member 61 abutting against the abutted portion (not shown) of the guide portions 28A and 28B. Here, the auxiliary caster 51 shown by solid lines in FIGS. 2 to 4 and 7 is located at the first position. At the first position, the auxiliary caster 51 does not overlap with the cart main body 20 in a plan view. 2, the locus T1 of the component (brake pedal 57) of the auxiliary caster 51 that is farthest from the pivot axis O2 when the auxiliary caster 51 is pivoted about the pivot axis O2 at the first position is shown by a two-dot chain line. As shown in FIG. 2, the locus T1 of the auxiliary caster 51 does not overlap with the locus T of the caster 31A. Furthermore, the locus T1 of the auxiliary caster 51 does not overlap with the locus (not shown) of the caster 31B. Furthermore, the locus T1 of the auxiliary caster 51 at the first position does not overlap with the cart main body 20.

[0044] In the first position, even when the transported goods are loaded onto the trolley main body 20 and the center of gravity of the transport trolley 10 including the transported goods becomes higher, the wheels 53a, 53b of the auxiliary caster 51, which is located outside the outer edge of the trolley main body 20, are in contact with the running surface, thereby preventing the transport trolley 10 from tipping over.

[0045] Furthermore, when the engaging member 82 is engaged with the engaging hole 62c, the connecting member 61 is inserted into the guide portions 28A and 28B, resulting in the smallest protrusion. This state corresponds to the auxiliary caster 51 attached to the connecting member 61 being located at a second position closer to the carriage main body 20 than the first position. The auxiliary caster 51 shown by the two-dot chain line in FIGS. 2 to 4 and 7 represents the case where the auxiliary caster 51 is located at the second position. At the second position, the auxiliary caster 51 overlaps with the carriage main body 20 in a plan view. Furthermore, in FIG. 2, the two-dot chain line indicates the locus T2 of the component of the auxiliary caster 51 that is farthest from the swivel axis O2 when the auxiliary caster 51 swivels around the swivel axis O2 at the second position. As shown in FIG. 2, the locus T2 of the auxiliary caster 51 at the second position does not overlap with the locus T of the caster 31A. Furthermore, the locus T2 of the auxiliary caster 51 at the second position does not overlap with the locus (not shown) of the caster 31B. Note that the locus T2 of the auxiliary caster 51 at the second position does not overlap with the cart main body 20 in part, but does overlap with the cart main body 20 in other part.

[0046] In the second position, the auxiliary caster 51 overlaps with the cart main body 20, so that even when the transport cart 10 is traveling in an aisle, the auxiliary caster 51 can be prevented from colliding with the wall of the aisle or the like.

[0047] Furthermore, when the engaging member 82 is engaged with the engaging hole 62b, the amount of protrusion of the connecting member 61 into the guide portions 28A and 28B is intermediate between the maximum and minimum. This state corresponds to the case where the auxiliary caster 51 attached to the connecting member 61 is located at a third position between the first position and the second position. 8 is a front view showing two stacked transport carts 10 with the auxiliary casters 51 positioned in the third position. 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, by placing the casters 31A, 31B of the upper transport cart 10 on the mounting members 32A, 32B of the lower transport cart 10, respectively, the overall height of the stacked transport carts 10 can be reduced by the height of the space 26 present above the mounting members 32A, 32B, compared to when the casters 31A, 31B are placed on the mounting portions 27.

[0048] However, when the transport carts 10 are stacked with the auxiliary casters 51 positioned at the first position, the auxiliary casters 51 protrude significantly in the left-right direction, causing the stacked transport carts 10 to become bulky in the left-right direction. Also, when the transport carts 10 are stacked with the auxiliary casters 51 positioned at the second position, the auxiliary casters 51 of the upper transport cart 10 are placed on the upper surfaces of the right frame portion 21c and the left frame portion 21d, or on the upper surface of the placement portion 27, causing the stacked transport carts 10 to become bulky in the height direction. On the other hand, as shown in Figure 8, when the transport carts 10 are stacked with the auxiliary casters 51 positioned in the third position, the auxiliary casters 51 can be prevented from protruding in the left-right direction, and the auxiliary casters 51 of the upper transport cart 10 do not overlap with the cart body 20 of the lower transport cart 10 and are not placed on the placement section 27, so the stacked transport carts 10 can be prevented from becoming bulky in the height direction. As a result, the stacked transport carts 10 can be stored and carried in and out compactly.

[0049] As described above, the transport cart 10 of this embodiment is equipped with auxiliary casters 51 located outside the outer periphery of the cart main body 20, so that even when transported goods are loaded onto the cart main body 20 and the center of gravity of the transport cart 10 including the transported goods becomes higher, the wheels 53a, 53b of the auxiliary casters 51 are in contact with the running surface at a position outside the outer periphery of the cart main body 20, thereby preventing the transport cart 10 from tipping over.

[0050] (Variation 1) The transport cart 10 of the first embodiment has been described above as being in constant contact with the running surface with the wheels 53a, 53b of the auxiliary caster 51, but this is not limited to this. The wheels 53a, 53b of the auxiliary caster 51 may be kept away from the running surface and may come into contact with the running surface when the transport cart 10 begins to tilt. Furthermore, when the wheels 53a, 53b of the auxiliary caster 51 are kept away from the running surface, the auxiliary caster 51 may be fixed in an orientation that prevents it from turning and allows the wheels 53a, 53b to rotate in the front-to-rear direction.

[0051] (Variation 2) The transport cart 10 of the first embodiment has been described above as having the auxiliary caster 51 with two wheels 53a, 53b, but this is not limiting. The auxiliary caster 51 may also have one wheel.

[0052] (Variation 3) The transporter 10 of the first embodiment has been described above as being capable of gradually shifting the auxiliary caster 51 to a first position, a second position, and a third position. However, this is not limiting. The auxiliary caster 51 may be configured to be able to shift to any position desired by the user between the first position and the second position, or may be fixed at any of the first, second, and third positions without being able to shift. Fixing the auxiliary caster 51 at any of the first, second, and third positions without being able to shift can be achieved by omitting the guide units 28A and 28B and directly or indirectly connecting the connecting member 61 to the transporter body 20. Alternatively, the auxiliary caster 51 may be configured to be able to gradually shift to any two of the first, second, and third positions, but not be able to shift to the remaining position. Alternatively, the auxiliary caster 51 may be configured to be able to shift to a fourth position different from the first to third positions.

[0053] (Variation 4) The transport cart 10 of the first embodiment has been described above as having the stopper portion 80 attached to the underside of the guide portions 28A and 28B, but this is not limitative. The stopper portion 80 may be attached to the front or rear of the guide portions 28A and 28B, or may be attached to the connecting member 61.

[0054] (Variation 5) The transporter cart 10 of the first embodiment described above has been described as being configured so that the connecting member 61 does not protrude further from the guide portions 28A, 28B than the first position, but this is not limited to this. The connecting member 61 may be configured so that it protrudes further from the guide portions 28A, 28B than the first position so that it can be detached from the guide portions 28A, 28B. By configuring it in this way, the ground contact units 50a to 50d can be attached to and detached from the cart main body 20. The present embodiment may be applied by appropriately combining or modifying the following embodiments and modifications.

[0055] [Second embodiment] 9 is a bottom view of the transporter carriage 110 according to the second embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. In the grounding units 150a to 150d of this embodiment, the connecting members 161 can be increased in amount to protrude from the guide portions 128A to 128D.

[0056] The carriage body 20 of this embodiment has guide portions 128A to 128D. Guide portions 128A and 128B are located between the two front casters 31A and the two central casters 31B, and guide portions 128C and 128D are located between the two rear casters 31A and the two central casters 31B. Guide portions 128A and 128B are located at a distance from each other in the front-to-rear direction, and guide portions 128C and 128D are located at a distance from each other in the front-to-rear direction.

[0057] In this embodiment, the grounding units 150a to 150d each have a connecting member 161 that constitutes the connecting portion 60. The connecting members 161 do not overlap each other when viewed from the left-right direction, but overlap each other when viewed from the front-rear direction. The connecting members 161 are elongated and are shorter than the left-right length of the bogie body 20 and longer than the guide portions 128A to 128D. In this embodiment, the connecting members 161 of the grounding units 150a and 150c are fitted into different guide portions 128B and 128A, respectively, and the connecting members 161 of the grounding units 150b and 150d are fitted into different guide portions 128D and 128C, respectively. In this way, by fitting the connecting members 161 into different guide portions 128A to 128D, the left-right length of the connecting members 161 can be increased by an amount that prevents interference with other connecting members 161.

[0058] Here, the auxiliary caster 51 shown by the solid line in Fig. 9 is located at the first position, and the auxiliary caster 51 shown by the two-dot chain line in Fig. 9 is located at the second position. By increasing the length of the connecting member 161 in the left-right direction, the amount by which the connecting member 161 protrudes from the guide portions 128A to 128D can be increased, and therefore, the auxiliary caster 51 can be located farther outward than the outer periphery of the cart main body 20 at the first position. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0059] [Third embodiment] 10 is a perspective view of a transporter carriage 210 according to the third embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. The ground contact units 250a to 250f of this embodiment are detachable from the carriage main body 20.

[0060] The transport cart 210 of this embodiment has six ground contact units 250a to 250f. Specifically, the transport cart 210 has three ground contact units 250a to 250c that are detachably attached to the right frame portion 21c, and three ground contact units 250d to 250f that are detachably attached to the left frame portion 21d. The grounding units 250a to 250f of this embodiment each have a connecting member 261 that extends linearly in the left-right direction. The connecting member 261 has a detachable portion 262 at the other end. The detachable portion 262 is shaped so that it can sandwich the right frame portion 21c or the left frame portion 21d of the cart main body 20 from above and below. Here, the right frame portion 21c and the left frame portion 21d correspond to an example of a detachable portion. A user can attach the grounding units 250a to 250f to the cart main body 20 by tightening the screws of the detachable portion 262 while the right frame portion 21c and the left frame portion 21d are sandwiched between the detachable portion 262. On the other hand, a user can detach the grounding units 250a to 250f from the right frame portion 21c or the left frame portion 21d by loosening the screws. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0061] (Variation 6) In the transport cart 210 of the third embodiment described above, the detachable portion attached to and detached from the detachable portion 262 is the right frame portion 21c or the left frame portion 21d, but this is not limited to this. The detachable portion attached to and detached from the detachable portion 262 may be the front frame portion 21a, the rear frame portion 21b, a reinforcing frame portion, or the mounting portion 27.

[0062] [Fourth embodiment] 11 is a perspective view of a transporter carriage 310 according to the fourth embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. The ground contact units 350a to 350f of this embodiment are detachable from the carriage main body 20.

[0063] The transport cart 310 of this embodiment has six ground contact units 350a to 350f. Specifically, the transport cart 310 has three ground contact units 350a to 350c that are detachably attached to the right frame portion 21c, and three ground contact units 350d to 350f that are detachably attached to the left frame portion 21d. Each of the grounding units 350a to 350f of this embodiment has a connecting member 361 that slopes downward as it extends outward in the left-right direction. The connecting member 361 has a detachable portion 362 at the other end. The detachable portion 362 has a configuration similar to the detachable portion 262 of the third embodiment. By slanting the connecting member 361, it is possible to prevent the grounding units 350a to 350f from becoming bulky in the height direction. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0064] [Fifth embodiment] 12 is a perspective view of a transport vehicle 410 according to the fifth embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and descriptions thereof will be omitted where appropriate. The grounding units 50a and 50b of this embodiment can be integrally moved between a first position and a second position, and the grounding units 50c and 50d can be integrally moved between the first position and the second position.

[0065] The ground unit 50a and the ground unit 50b are integrated by bridging the interlocking member 420 between their respective connecting members 61. Therefore, the connecting member 61 of the ground unit 50a and the connecting member 61 of the ground unit 50b are interlocked to slide on the guide portions 28A and 28B, so that the auxiliary casters 51 of the ground unit 50a and the auxiliary casters 51 of the ground unit 50b can move integrally between the first position and the second position. Similarly, the ground unit 50c and the ground unit 50d are integrated by bridging the interlocking member 420 between their respective connecting members 61, so that the auxiliary casters 51 of the ground unit 50c and the auxiliary casters 51 of the ground unit 50d can move integrally between the first position and the second position. By integrating the ground units, the rigidity of the ground units can be improved. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0066] [Sixth embodiment] 13 is a perspective view of a transport cart 510 according to the sixth embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. The ground contact units 550a to 550d of this embodiment are configured by replacing the auxiliary casters 51 of the first embodiment with leg members 551.

[0067] The grounding units 550a to 550d of this embodiment each have a leg member 551 and a connecting portion 60. The leg member 551 corresponds to an example of a grounding portion. The leg member 551 is located outside the outer periphery of the dolly main body 20, and the lower end of the leg member 551 is spaced apart from the running surface. The leg member 551 comes into contact with the running surface when the transporting dolly 510 begins to tilt, thereby preventing the transporting dolly 510 from tipping over. The leg member 551 has a portion that comes into contact with the running surface made of a flexible material such as synthetic rubber or synthetic resin. Therefore, when the leg member 551 comes into contact with the running surface, the running surface will not be damaged. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0068] [Seventh embodiment] 14 is a perspective view of a transporter truck 610 according to the seventh embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and descriptions thereof will be omitted where appropriate. The ground contact units 650a to 650d of this embodiment swing relative to the truck body 20, thereby allowing the auxiliary casters 51 to transition between a first position and a second position.

[0069] The grounding units 650a to 650d of this embodiment each have a connecting member 661 that constitutes the connecting portion 60. The connecting member 661 connects the auxiliary caster 51 to the cart main body 20. The connecting member 661 is a substantially L-shaped member in which a portion extending in the horizontal direction and a portion extending in the vertical direction intersect at right angles. The auxiliary caster 51 is attached to one end of the connecting member 661. In addition, the other end of the connecting member 661 is supported by a bracket 620, and is capable of swinging around a swing axis S that extends in the vertical direction.

[0070] The state in which the connecting member 661 is aligned in the left-right direction corresponds to the case in which the auxiliary caster 51 attached to the connecting member 661 is located at a first position outside the outer periphery of the cart main body 20. Note that the connecting member 661 abuts against a part of the bracket 620, so that the auxiliary caster 51 does not protrude further rearward or forward from the cart main body 20 than the first position. Here, the auxiliary caster 51 shown by the solid line in Fig. 14 is located at the first position. At the first position, the wheel of the auxiliary caster 51 located outside the outer periphery of the cart main body 20 is in contact with the running surface, so that the transport cart 10 can be prevented from tipping over.

[0071] On the other hand, the state in which the connecting member 661 is aligned in the front-to-rear direction corresponds to the case in which the auxiliary caster 51 attached to the connecting member 661 is located at a second position that is closer to the cart main body 20 than the first position. Here, the auxiliary caster 51 indicated by the two-dot chain line in Fig. 14 is located at the second position. At the second position, it is possible to prevent the auxiliary caster 51 from protruding in the left-right direction. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0072] (Variation 7) In the seventh embodiment described above, the transport cart 610 is described as having a connecting member 661 that is a substantially L-shaped member in which the horizontally extending portion and the vertically extending portion intersect at right angles, but the present invention is not limited to this. The connecting member 661 may be a member that is made up of a portion that extends horizontally, or may be a member that is inclined downward as it extends outward.

[0073] [Eighth embodiment] 15 is a bottom view of a transporter cart 710 according to the eighth embodiment. Note that the same components as those in the first embodiment are given the same reference numerals and the description thereof will be omitted as appropriate. The transport cart 710 of this embodiment has four casters 31A arranged at the four corners of the cart main body 20. The transport cart 710 of this embodiment also has two grounding units 750a, 750b. Specifically, the transport cart 710 has one grounding unit 750a adjacent to the right frame portion 21c and one grounding unit 750b adjacent to the left frame portion 21d. The grounding units 750a and 750b are positioned symmetrically with respect to the center line C. The connecting member 61 of the grounding unit 750a and the connecting member 61 of the grounding unit 750b are fitted from opposite sides into a guide portion 728A located in the center in the front-to-rear direction. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0074] [Ninth embodiment] 16 is a bottom view of a transporter cart 810 according to the ninth embodiment. Note that the same components as those in the first embodiment are given the same reference numerals and the description thereof will be omitted as appropriate. The transporter cart 810 of this embodiment has four casters 31A arranged at the four corners of the cart main body 20. The transporter cart 810 of this embodiment also has three ground contact units 850a to 850c. Specifically, the transporter cart 810 has two ground contact units 850a and 850b adjacent to the right frame portion 21c, and one ground contact unit 850c adjacent to the left frame portion 21d. The ground contact units 850a, 850b and the ground contact unit 850c are positioned asymmetrically with respect to the center line C. The connecting members 861 of the ground contact units 850a to 850c are fitted into different guide portions 828A, 828C, and 828B arranged at intervals in the front-rear direction, respectively. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0075] [Tenth embodiment] 17 is a bottom view of a transporter cart 910 according to the tenth embodiment. Note that the same components as those in the first embodiment are given the same reference numerals and the description thereof will be omitted as appropriate. The transporter cart 910 of this embodiment has four casters 31A arranged at the four corners of the cart main body 20. The transporter cart 910 of this embodiment also has six ground contact units 950a to 950c. Specifically, the transporter cart 910 has three ground contact units 950a to 950c adjacent to the right frame part 21c, and three ground contact units 950d to 950f adjacent to the left frame part 21d. The ground contact units 950a to 950c and the ground contact units 950d to 950f are positioned symmetrically with respect to the center line C. The connecting member 61 of grounding unit 950a and the connecting member 61 of grounding unit 950d are fitted into guide portion 928A located on the front side from opposite sides, the connecting member 61 of grounding unit 950b and the connecting member 61 of grounding unit 950e are fitted into guide portion 928B located in the center from opposite sides, and the connecting member 61 of grounding unit 950c and the connecting member 61 of grounding unit 950f are fitted into guide portion 928C located on the rear side from opposite sides. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0076] [Eleventh embodiment] 18 is a bottom view of a transporter 1010 according to the eleventh embodiment. Note that the same components as those in the first embodiment are given the same reference numerals and the description thereof will be omitted as appropriate. The transporter cart 1010 of this embodiment has four casters 31A arranged at the four corners of the cart body 20. The transporter cart 1010 of this embodiment also has five grounding units 1050a to 1050e. Specifically, the transporter cart 1010 has three grounding units 1050a to 1050c adjacent to the right frame part 21c and two grounding units 1050d and 1050e adjacent to the left frame part 21d. The grounding units 1050a to 1050c and the grounding units 1050d and 1050e are positioned asymmetrically with respect to the center line C. The connecting members 1061 of the grounding units 1050a to 1050e are fitted into different guide parts 1028A, 1028C, 1028E, 1028B, and 1028D arranged at intervals in the front-rear direction, respectively. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0077] [Twelfth embodiment] 19 is a bottom view of a transporter cart 1110 according to the twelfth embodiment. Note that the same components as those in the first embodiment are given the same reference numerals and the description thereof will be omitted as appropriate. The transporter cart 1110 of this embodiment has six casters: four casters 31A arranged at the four corners of the cart body 20 and two casters 31C arranged at the center in the left-right direction and spaced apart in the front-rear direction. The casters 31C are attached to the cart body 20 via mounting members 32C. The transporter cart 1110 of this embodiment has four grounding units 1150a to 1150d. Specifically, the transporter cart 1110 has two grounding units 1150a and 1150b adjacent to the right frame portion 21c and two grounding units 1150c and 1150d adjacent to the left frame portion 21d. The grounding units 1150a and 1150c are positioned symmetrically with respect to the center line C, with the front caster 31C in between, and the grounding units 1150b and 1150d are positioned symmetrically with respect to the center line C, with the rear caster 31C in between. The connecting members 1161 of the grounding units 1150a to 1150d are fitted into different guide portions 1128A to 1128D that are arranged separately in the front, rear, left and right directions. The present embodiment may be applied by appropriately combining or modifying the above-described or later-described embodiments and modifications.

[0078] [Thirteenth embodiment] 20 is a bottom view of a transporting cart 1210 according to the thirteenth embodiment. Note that the same components as those in the first and twelfth embodiments are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. The transporter cart 1210 of this embodiment has eight casters: four casters 31A arranged at the four corners of the cart main body 20, two casters 31B arranged at the center in the front-rear direction and spaced apart on the left and right, and two casters 31C arranged at the center in the left-right direction and spaced apart on the front and rear. The transporter cart 1210 of this embodiment also has four grounding units 1150a to 1150d. Specifically, the transporter cart 1210 has two grounding units 1150a and 1150b adjacent to the right frame part 21c and two grounding units 1150c and 1150d adjacent to the left frame part 21d. The grounding units 1150a and 1150c are positioned symmetrically with respect to the center line C, with the front caster 31C in between, and the grounding units 1150b and 1150d are positioned symmetrically with respect to the center line C, with the rear caster 31C in between. The connecting members 1161 of the grounding units 1150a to 1150d are fitted into different guide portions 1128A to 1128D that are arranged separately in the front, rear, left and right directions. The above-described embodiments and modifications may be combined or modified as appropriate and applied to this embodiment.

[0079] [Fourteenth embodiment] Fig. 21 is a bottom view of a transport cart 1310 according to the fourteenth embodiment. Fig. 22 is a plan view of the transport cart 1310. Fig. 23 is a front view of the transport cart 1310. Fig. 24 is a side view of the transport cart 1310. Note that the same components as those in the first embodiment will be given the same reference numerals, and descriptions thereof will be omitted as appropriate.

[0080] The carriage body 1320 of this embodiment does not have a mounting portion 27. Therefore, the running surface is exposed through the space 26 that is not closed by the mounting members 32A and 32B in a plan view. Furthermore, the guide portions 28A and 28B that are long in the left-right direction are exposed through the space 26 that is not closed by the mounting members 32A and 32B in a plan view. The ground contact units 1350a to 1350d of this embodiment have auxiliary casters 1351. The auxiliary casters 1351 are casters without brakes. Also, as shown in Fig. 23, the auxiliary caster 1351 includes only one wheel 1353.

[0081] 25 is a side view of the transport cart 1310 with the casters 31A and 31B rotated 90 degrees around the rotation axis O1, and the auxiliary caster 1351 rotated 90 degrees around the rotation axis O2. By rotating the caster 31A, a gap G is formed between the front caster 31A and the ground contact unit 1350c, and between the rear caster 31A and the ground contact unit 1350d. By inserting the prongs of a pair of forks of a forklift into the gap G, the transport cart 1310 can be transported by the forklift. The above-described embodiments and modifications may be combined or modified as appropriate and applied to this embodiment.

[0082] [Fifteenth embodiment] 26 is a diagram showing an example of the configuration of a grounding unit 1450 according to the fifteenth embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. As shown in Figure 26(a), the grounding unit 1450 of this embodiment has an auxiliary caster 51 and a connecting portion 1460. A connecting member 1461 of the connecting portion 1460 is elongated.

[0083] As shown in FIG. 26(b), the connecting member 1461 has a generally I-shaped (or generally H-shaped) cross section. An auxiliary caster 51 is rotatably attached to the lower end of the longitudinal end of the connecting member 1461. Furthermore, both front and rear ends of the upper end of the connecting member 1461 are held by a pair of holding portions 1429 of the guide portion 1428A so as to embrace them from the front, rear, and lower sides, allowing the connecting member 1461 to slide along the longitudinal direction of the guide portion 1428A. The connecting member 1461 is not limited to having a generally I-shaped cross section, and can be modified as appropriate, such as a connecting member 1462 in FIG. 26(c) having a generally II-shaped cross section in which two generally I-shaped cross sections are combined in parallel front and rear. The above-described embodiments and modifications may be combined or modified as appropriate and applied to this embodiment.

[0084] Although the present invention has been described above using the above-described embodiments, the present invention is not limited to the above-described embodiments, and the configurations and examples of the above-described embodiments can be combined or modified as appropriate. In the above embodiment, the case where each transport cart has the placement portion 27 has been described, but this is not limitative, and the placement portion 27 may be omitted. [Explanation of symbols]

[0085] 10: Transport cart 20: Cart body 31A, 31B: Caster 33: Wheel 51: Auxiliary caster 53a, 53b: Wheel 60: Connection part 80: Stopper part 262: Detachable part

Claims

1. a carriage body portion on which an object to be transported is loaded; Casters arranged at at least four corners of the cart body; a ground contact portion located outside the outer periphery of the carriage body portion.

2. The transporting dolly according to claim 1, further comprising a connecting portion that connects the ground contact portion to the dolly body portion.

3. The connecting portion is 3. The transporting carriage according to claim 2, wherein the ground contact portion is transitioned between a first position away from the carriage body portion and a second position closer to the carriage body portion than the first position.

4. The connecting portion is The transporting cart according to claim 3, wherein the ground contact portion is moved between the first position and the second position by sliding or swinging relative to the cart body portion.

5. The bogie body portion or the coupling portion is 5. The transporting cart according to claim 4, further comprising a stopper portion for stopping the sliding or swinging of the connecting portion at the first position and the second position.

6. The stopper portion is 6. The transporting cart according to claim 5, further comprising a release portion for releasing the stoppage of the sliding or swinging of the connecting portion.

7. The stopper portion is A transporting cart as described in claim 5 or 6, characterized in that the ground contact portion stops sliding or swinging at a third position that is farther away from the cart main body portion than the second position and closer to the cart main body portion than the first position.

8. A transporting cart according to any one of claims 3 to 7, characterized in that the ground contact portion does not overlap with the cart main body portion in the first position when viewed in a plane, and overlaps with the cart main body portion in the second position.

9. The bogie body has a pair of opposing frame parts that form an outer shape, The transport cart has, as the ground contact portion, a grounding portion on one side located outside an outer periphery of one of the pair of opposing frame portions; and a second grounding portion located outside an outer periphery of the other of the pair of opposing frame portions, 9. The transporting cart according to claim 2, wherein the grounding portion on one side and the grounding portion on the other side overlap each other in a side view perpendicular to the longitudinal direction of the frame portion.

10. The transport cart has, as the connecting portion, a connecting portion on one side that connects the grounding portion on one side to the bogie body portion; a connecting portion on the other side that connects the grounding portion on the other side to the bogie body portion, 10. The transporting cart according to claim 9, wherein the connecting portion on one side and the connecting portion on the other side slide in a direction perpendicular to the longitudinal direction of the frame portion.

11. 11. The transporting dolly according to claim 1, wherein the ground contact portion is a second caster different from the caster.

12. 12. The transport cart according to claim 11, wherein the second caster has a wheel with an outer diameter smaller than that of the wheel of the first caster.

13. 13. The transporting cart according to claim 11 or 12, wherein the second caster is rotatable about a rotation axis extending in the vertical direction.

14. 14. The transporting cart according to claim 1, wherein the ground contact portion is disposed away from a ground surface, and contacts the ground surface when the transporting cart begins to tilt.

15. 11. The transporting cart according to claim 2, wherein the connecting portion has a detachable portion that is detachable from the detachable portion of the cart body.

Images