JP2007283806A - Omnidirectionally moving wheel and transport dolly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an omnidirectionally moving wheel and a transport dolly capable of being embodied in a small size and at low cost, equipped with a high rigidity, capable of suppressing variation in the operating force in the advancing direction, and accomplishing transportation while the straight running performance is secured, and also free of generation of vibrations. <P>SOLUTION: The omnidirectionally moving wheel is fitted with a plurality of barrel-shaped rollers 3 in the circumferential arrangement centering on the center axle 1, and each roller 3 is borne by a frame 2 rotatably round the barrel-shaped roller shaft perpendicularly intersecting the center axle 1. A sliding part 4 having a small friction coefficient is arranged between two rollers 3, and the outer edges of the sliding parts 4 from the center axle 1 constitute the wheel surface together with the outer edges of the rollers 3 from the center axle 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an omnidirectional wheel that prevents a side slip during straight conveyance and does not generate vibration, and a conveyance carriage including the wheel.

Conventionally, a traveling caster is disposed on the lower surface of a carriage such as a bed used in a hospital or the like, thereby enabling the conveyance carriage to move and change its direction by human power or electric power. This transport cart with casters has conveniences such as being able to transport on a flat surface with a light force and being free to move. However, since the caster is offset from the wheel axis and the vertical axis, a phenomenon of shaking the neck occurs. That is, when the bed or the like is transported, the wheel rotates around the support column. For this reason, the transport cart with casters requires different operating forces depending on the relative angle between the traveling direction and the caster direction.

  FIG. 7 is a graph showing the relationship between the weight of the bed and the operating force. In FIG. 7, the case where the caster direction and the traveling direction coincide with the case where the phase between the caster direction and the traveling direction is shifted by 90 °, the wheel diameter φ of the caster is set to 100 mm, 125 mm, The relationship is examined by changing it to 150 mm. As shown in FIG. 7, when the caster direction and the traveling direction coincide with each other when the bed is moved, the operating force is 100 N (Newton) or less for a bed of 400 kg or less, while the caster is started at the start. When the direction and the traveling direction are 90 ° out of phase, an operation force of about 100 N is required even if the bed weight is 100 kg, and when the bed weight is 400 kg, the operation force is more than 300 N. As described above, the transport cart with casters has a problem that the operating force increases depending on the transport direction due to the swinging of the casters.

  In contrast, an omnidirectional moving wheel that can move in all directions on a horizontal plane is holonomic, so there is no increase in operating force due to swinging like a caster, and a transport cart provided with omnidirectional moving wheels is a flat surface. The top can be operated freely with light force. While the caster had to secure an operation space by swinging, the omnidirectional wheel can reduce the operation space by not shaking the head. As such a transport carriage, for example, there is a conventional technique disclosed in Patent Document 1.

  FIG. 8 shows an omnidirectional moving wheel attached to the moving carriage described in Patent Document 1, and is (a) a side view and (b) a front view. As shown in FIG. 8A, the conventional omnidirectional wheel has a plurality of (four in the illustrated example) barrels 122 on the outer periphery of a frame 121 provided with a central axle 120. 122 is rotatable around an axis orthogonal to the axial direction and the radial direction of the central axle 120. FIG. 8A shows a longitudinal section including a rotation axis (not shown) of each barrel 122, and the outer peripheral portion of the barrel 122 constitutes a part of the circumference centering on the central axle 120. Yes. For this reason, the omnidirectional moving wheel can move in all directions by rotation around the central axle 120 and rotation around the rotation axis of each barrel 122. Further, as shown in FIG. 8B, the plurality of barrels 122 are provided in two rows, and in both rows, the arrangement of the barrels 122 around the central axle 120 is shifted by a half pitch. Thereby, the state where the barrel 122 is always grounded is obtained. By installing the omnidirectional moving wheel configured as described above in the moving carriage, for example, even a heavy bed can be easily conveyed in all directions.

  Patent Document 2 also describes an omnidirectional vehicle wheel. FIG. 9 shows an omnidirectional vehicle wheel disposed in an omnidirectional vehicle described in Patent Document 2, and is (a) a side view and (b) a front view. As shown in FIGS. 9 (a) and 9 (b), the omnidirectional vehicle wheel according to the conventional technology is fixedly disposed so as to penetrate the drive shaft 212 and the drive shaft 212 so as to be orthogonal to the central portion. A circular plate-like member 214, a support arm 215 extending radially from the plate-like member 214, a polygonal annular member 217 supported on the outer periphery of the plate-like member 214 by the support arm 215, A first barrel-shaped free roller 216 provided rotatably on the long side portion 217a of the annular member 217; a second barrel-type free roller 218 provided rotatably on the short side portion 217b of the annular member 217; It is configured with. The first barrel type free roller 216 and the second barrel type free roller 218 are equal in size in the radial direction, while the first barrel type free roller 216 is the second barrel type free roller 218. It is formed so as to be longer in the axial direction.

JP 2001-233219 A JP 2001-253364 A

  However, the above-described prior art has the following problems.

  In a transport cart with casters, there is a problem that casters require a large operating force depending on the traveling direction due to the non-holonomic characteristics. In addition, there is a problem that it is easy to meander and skid under the influence of the road surface.

  On the other hand, the omnidirectional moving wheel eliminates the problem of swinging of the caster, but is liable to cause a side slip like the caster. In addition, since a plurality of barrels or barrel-type free rollers serving as the ground contact surfaces are alternately contacted, there is a problem that vibration occurs when the barrel or barrel-type free rollers are switched. On the other hand, there are some which suppress vibration by using a large number of barrel or barrel-type free rollers, but there are many practical problems such as difficulty in reducing the wheel diameter and increased cost. .

  Here, the subject in the case of using an omnidirectional moving wheel similarly to a caster is described in detail. First, rigidity is required for an omnidirectional moving wheel. That is, when considering a caster disposed on a transport carriage, it is presumed that the rigidity against static load exceeds 100 kgf (weight kilogram) and several times as large as the impact load. Therefore, rigidity that can withstand this condition is required. Also, smoothness is required. That is, in consideration of the influence on the conveyed product, it is necessary to prevent the vibration caused by the omnidirectional moving wheel from being generated. In addition, layout is also required, and it is desirable that the size of the omnidirectional wheel used for the caster is small considering the layout on the transport carriage. Furthermore, when versatility is taken into consideration, it is necessary that the cost be low.

  As described above, it is necessary to satisfy the four conditions (rigidity, smoothness, layout, and low cost) at the same time. However, the conventional technology does not satisfy these conditions at the same time. For example, FIG. 10A is a perspective view showing a first conventional example of an omnidirectional moving wheel product, and shows a multidirectional and powered conveyor wheel manufactured by Transwheel. In this product, the strength around the barrel shaft 124 cannot be given, and it is difficult to ensure rigidity. Moreover, since the recessed part 123 formed between the barrels 122 occupies nearly 50% of the outer periphery of the wheel, there is a problem that vibration occurs during transportation.

  FIG. 10 (b) is a perspective view showing a second conventional example of an omnidirectional moving wheel product. Multi-Directional Wheel 1.9 "Dia, 1.2" Bore (Robot Objects) WHL-RF190-12R). In this product, the barrel 122 has acute angle portions 125 at both ends in the longitudinal direction, and since the acute angle wheel portions are cantilevered, it is difficult to ensure rigidity.

  FIG. 10C is a perspective view showing a third conventional example of an omnidirectional moving wheel product, and shows a special front wheel WESN (R) manufactured by Kanto Automobile. This product is a standard specification omnidirectional wheel with a wheel diameter φ = 300 mm used for a wheelchair. As shown in FIG. 10 (c), in order to ensure rigidity, the circumference must be made large, and it is difficult to reduce the size (the current product has a minimum wheel diameter of φ = 250 mm, which is generally Wheel diameter φ = about 50 to 125 mm). In addition, the number of barrels 122 is large, the number of parts is large, and it is difficult to reduce the cost.

  Further, even in the omnidirectional moving wheel described in Patent Document 2, in order to ensure rigidity, a large circumference must be taken and it is difficult to reduce the size (the current product has a minimum wheel diameter φ = 132 mm, general wheel diameter φ = about 50 to 125 mm). There is also a problem that the number of parts is large and it is difficult to reduce the cost.

  The present invention has been made in view of such problems, and is small in size, low cost, and highly rigid, suppresses fluctuations in operating force in the traveling direction, and realizes conveyance while ensuring straightness. An object of the present invention is to provide an omnidirectional moving wheel and a transport carriage that do not generate vibration.

  An omnidirectional moving wheel according to the present invention includes a central axle, a frame attached to the central axle, a circumferential direction centered on the central axle in a virtual plane orthogonal to the central axle, and the central axle. A plurality of barrel rollers pivotally supported by the frame so as to be rotatable around orthogonal barrel roller shafts and an outer edge from the central axle are disposed between the barrel rollers in the virtual plane. A sliding portion supported by the frame so as to form a peripheral surface of the axle together with an outer edge from the central axle of the mold roller, and the barrel roller and the slide by rotation about the central axle It is movable in the first direction by alternately grounding the moving part, and in a second direction orthogonal to the first direction by the rotation of the barrel roller around the barrel roller axis. Specially movable To.

  It is preferable that the friction coefficient in the circumferential direction around the central axle in the sliding portion is smaller than the friction coefficient in the axial direction of the central axle in the sliding portion.

  The sliding portion may alternately include a grounding portion and a non-grounding portion along a circumferential direction around the central axle.

  The same rotary body as the one set of the rotary body composed of the barrel roller and the sliding portion is provided in another virtual plane orthogonal to the central axle, and the two sets of rotary bodies are the barrel roller. It is preferable that the arrangements of these are shifted from each other by a half pitch.

  The barrel roller may be formed of urethane. The sliding portion may be made of nylon.

  It is preferable that an outer edge of the sliding portion centering on the central axle is designed to be smaller than an outer edge of the barrel roller.

  The conveyance trolley | bogie which concerns on this invention is equipped with the said omnidirectional movement wheel, It is characterized by the above-mentioned.

  According to the present invention, in an omnidirectional moving wheel in which a plurality of barrel rollers are pivotally supported on a frame attached to a central axle, a sliding portion supported by the frame is arranged between barrel rollers, and sliding The outer edge from the central axle of the part constitutes the peripheral surface of the axle together with the outer edge from the central axle of the barrel-shaped roller, thereby suppressing vibration during transportation by the transportation carriage having omnidirectional moving wheels, It is possible to prevent the skidding and to convey while ensuring linearity.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. First, an omnidirectional moving wheel according to a first embodiment of the present invention will be described. Fig.1 (a) is a side view which shows the omnidirectional movement wheel which concerns on this embodiment, (b) is a front view.

  First, it demonstrates using Fig.1 (a) which is a side view of the omnidirectional wheel of this embodiment. This side view is a cross-sectional view of a virtual plane orthogonal to the central axle 1, and more specifically, an AA cross-sectional view that is a virtual plane orthogonal to the central axle 1 in the front view shown in FIG. It is shown. As shown in FIG. 1 (a), in the omnidirectional moving wheel of this embodiment, a frame 2 is attached around a central axle 1, and the frame 2 can be rotated together with the central axle 1. A plurality of (three in the illustrated example) barrel rollers 3 are disposed in the frame 2 in the circumferential direction around the central axle 1, and these barrel rollers 3 are each orthogonal to the central axle 1. The barrel 2 is rotatably supported around the barrel roller shaft 13. FIG. 1A shows a longitudinal section including the barrel roller shaft 13, and the outer edge of each barrel roller 3 constitutes a part of the circumference centered on the central axle 1. In other words, the outer edges of these three barrel rollers 3 constitute the wheel surface of the omnidirectional moving wheel. Further, between the barrel rollers 3, sliding portions 4 having a small friction coefficient are provided, and the sliding portions 4 are fixed to the frame 2 with screws 14. The outer edge of the sliding portion 4 from the central axle 1 constitutes the peripheral surface of the axle together with the outer edge of the barrel roller 3 from the central axle 1, and the outer edge of the sliding portion 4 moves in all directions. It constitutes a part of the wheel surface of the wheel. Further, the outer edge of the frame 2 between the sliding part 4 and the barrel roller 3 is not grounded as a wheel surface. Further, the outer edge of the sliding portion 4 centering on the central axle 1 is designed to be smaller than the outer edge of the barrel roller 3.

  Thus, the omnidirectional moving wheel in this embodiment is provided with the sliding portion 4 having a small friction coefficient as a part of the wheel surface between the barrel rollers 3 constituting the wheel surface. Hereinafter, when the wheel surface of the omnidirectional moving wheel is grounded and transported, the direction of rotational movement around the central axle 1 is referred to as a straight traveling direction, and the direction orthogonal to the straight traveling direction is referred to as a lateral direction. The sliding portion 4 needs to have a small coefficient of friction in the straight direction so as not to apply a large load to the conveyance in the straight direction. However, the coefficient of friction in the lateral direction of the sliding portion 4 is assumed to be a value that prevents side-slip during straight-forward conveyance and ensures straight-running performance. However, if the coefficient of friction in the lateral direction is too large, it is difficult to move in the lateral direction with the barrel roller 3 and a part of the sliding portion 4 in contact with each other. Therefore, the coefficient of friction in the lateral direction is not so great as to prevent lateral movement.

  For example, as shown in FIG. 6A, the shape of the outer edge which is the ground contact surface of the sliding portion 4 is an arc shape in the longitudinal direction of the outer edge 11, and the surface thereof is uniform. In FIG. 6A, the base part constituting the sliding portion 4 and the outer edge material covering the base part and forming the grounding surface are different, the outer edge material is, for example, nylon, and the base part is, for example, a stiff and excellent rigid body. It may be of material. The longitudinal direction is the circumferential direction centered on the central axle, and the short side direction is the lateral direction. If the sliding part 4 increases the friction in the lateral movement and hinders the lateral movement, the outer edge 11 of the sliding part 4 is provided with, for example, a lateral slit to reduce the friction. On the other hand, grip force can be obtained in the straight direction. FIG. 6B shows that the frictional force in the lateral direction is reduced by forming a wave-like shape in the longitudinal direction on the outer edge of the sliding portion 4 and alternately arranging the grounding surface and the non-grounding surface. The grip force is obtained in the straight direction. That is, in FIG. 6B, compared with FIG. 6A, the ground contact area is reduced and the lateral friction is reduced. In FIG. 6 (b), as in FIG. 6 (a), the base part constituting the sliding part 4 and the material of the outer edge that covers this base part and forms the ground contact surface are different. The material of the outer edge is, for example, nylon. The base may be made of a hard material having excellent rigidity, for example. Moreover, you may make the shape of the outer edge of the sliding part 4 like FIG.6 (c). 6C, in addition to the shape of FIG. 6B, an arc-shaped contact surface 12 is provided along the longitudinal direction at the center in the short direction of the outer edge 11, and the outer edge 11 of the sliding portion 4 is provided. A ground plane is always present at a part of the surface to reduce vibration during transportation.

  From the viewpoint of the friction coefficient as described above, for example, nylon is used as the material of the sliding portion 4 as a slippery property. Further, as the material of the barrel roller 3, for example, urethane is used. However, since urethane is easily deformed, when urethane is used for the barrel roller 3, the outer diameter of the barrel roller 3 is reduced by the load of the conveyed product. Therefore, the sliding portion 4 is designed with a minus tolerance with respect to the radial direction of the central axle 1.

  As shown in FIG. 1B, the barrel rollers 3 are provided in two rows in the axial direction of the central axle 1, and in both rows, the arrangement of the barrel rollers 3 around the central axle 1 is shifted by a half pitch. It is. As a result, a state in which the barrel roller 3 is always in contact with the ground is obtained.

  Next, the operation of this embodiment will be described. A case will be considered in which the omnidirectional moving wheels of the present embodiment are installed in a transport cart and the transport cart is transported. At the time of conveyance in the straight traveling direction, the omnidirectional moving wheel rotates around the central axle 1, and the barrel roller 3 and the sliding portion 4 are alternately grounded and rotated. At this time, the sliding part 4 suppresses a side slip by friction. Further, when transporting in the horizontal direction, the barrel-shaped roller 3 is transported from the grounded state by rotation about the rotation axis of the barrel-shaped roller 3. Note that when the barrel roller 3 and a part of the sliding part 4 are to be transported in a lateral direction from a grounded state, the sliding part 4 becomes a load, but the lateral friction coefficient hinders the transportability. It is assumed that it is set so as not to cause a problem. As described above, the omnidirectional moving wheel of the present embodiment can move in all directions on the horizontal plane by rotating around the central axle 1 and rotating around the rotating shaft of each barrel roller 3. ing.

  The effect of this embodiment will be described. When the omnidirectional wheel is rotated in the straight direction, the barrel roller 3 and the sliding portion 4 are alternately grounded and rotated, and when the barrel roller 3 changes, the outer edge from the central axle 1 is the barrel roller. Since the sliding part 4 that constitutes the peripheral surface of the axle together with the outer edge from the central axle 1 is grounded, vibration during movement does not occur as in the case where there is no sliding part 4, and it is transported smoothly. Can do. Further, the lateral friction by the sliding portion 4 prevents the side slip and improves the straightness. Moreover, the sliding part 4 is arrange | positioned between the barrel-type rollers 3, By adding this, the magnitude | size of an omnidirectional moving wheel is not affected, but size reduction is possible. Further, the number of barrel-shaped rollers 3 and sliding portions 4 is three, respectively, and the number of parts is small, so that the cost can be reduced. Furthermore, the strength around the barrel roller shaft 13 is reinforced by the sliding part 4, and the rigidity of the omnidirectional moving wheel is ensured.

  Next, a transport cart according to a second embodiment of the present invention will be described. FIG. 2 is a perspective view showing the transport carriage according to the present embodiment. As shown in FIG. 2, the transport carriage 5 of the present embodiment uses the omnidirectionally moving wheels of the first embodiment as casters, and is provided at the four corners of the lower surface of the base portion 8 on which the object to be transported is placed. The omnidirectional moving wheels 6 of the first embodiment are provided via the support shafts 7 respectively. Further, when the mounting direction of the omnidirectional moving wheel 6 is set parallel to the longitudinal direction of the platform 8, the barrel roller fits into the groove during conveyance when the floor has a groove having a width equal to the diameter of the barrel roller. Sometimes it becomes difficult to get over the steps. For this reason, in this embodiment, with respect to the pair of omnidirectional moving wheels 6 provided at the front end of the traveling direction 9 of the transport carriage 5, the mounting direction is a square shape with respect to the traveling direction 9. It is preferable.

  In this embodiment, since the omnidirectional moving wheel of the first embodiment is used, the same operation as that of the first embodiment is realized, and unlike the case where a caster is used, the conveyance carriage is operated. The maximum operating force at the time can be greatly reduced, and conveyance in all directions becomes possible. Moreover, since the sliding part 4 is provided in the omnidirectional moving wheel 6, the vibration at the time of conveyance is suppressed. Furthermore, side slip is prevented by the friction of the sliding portion 4 in the lateral direction, and conveyance can be realized while ensuring straightness, so that operability can be improved. Further, by making the rotational frictional resistance of the central axle smaller than the rotational frictional resistance of the barrel roller shaft, it is difficult to move in the lateral direction, so that the straight traveling performance is improved. In particular, conventionally, an additional device such as providing a center wheel at the center of the lower surface of the carriage carriage as a means for improving the operability against skidding has been required. However, in this embodiment, such an additional device is omitted. can do. In addition, when the present inventors made a prototype of this embodiment, it was confirmed that this embodiment is effective in terms of bodily sensations.

  3 and 4 respectively show a first modification and a second modification of the second embodiment. In FIG. 3, a pair of omnidirectional moving wheels 6 is provided at the front end portion in the traveling direction 9 of the transport carriage 5, and the omnidirectional moving wheels 6 are the omnidirectional moving wheels of the first embodiment. is there. A pair of conventional casters 10 is provided at the rear end of the traveling direction 9 of the transport carriage 5. In this way, by providing the omnidirectional moving wheel of the present invention at the front end of the traveling direction 9 of the transport carriage 5, compared with the case where all the wheels of the transport carriage are configured by conventional casters, Since the frictional resistance can be reduced, straight transportability is improved, and further, there is an effect that there is less play at the time of transport and ride comfort is improved. In FIG. 4, conventional casters 10 are provided at four corners of the lower surface of the base portion 8 of the transport carriage 5 via support shafts 7, respectively. An omnidirectional moving wheel 6 is provided. In this modified example, although conventional casters are disposed at the four corners of the transport carriage 5, the rotational friction resistance of the central axle and the rotation of the barrel roller shaft with respect to the omnidirectional moving wheel 6 itself in the central portion. A difference is provided between the frictional resistance and the rotational frictional resistance of the central axle is made smaller than the rotational frictional resistance of the barrel roller shaft, thereby improving the straight conveyance property. Since other configurations in these modified examples are the same as those in the second embodiment, the same components as those in FIG. 2 are denoted by the same reference numerals in FIG. 3 and FIG. Description is omitted.

Here, the setting method of the friction coefficient of the sliding part 4 is described. The longitudinal direction which is the direction along the outer periphery centering on the central axle 1 of the sliding part 4 and the transverse friction coefficient orthogonal to the longitudinal direction are respectively the longitudinal friction coefficient: μ _f and the transverse friction coefficient: μ _s. In this case, the inventors experimentally confirmed that the straightness is improved when μ _s is about twice as large as μ _f (see FIG. 5). In addition, it has been experimentally confirmed that a normal male can be carried out if the pushing direction operating force is about 150 N and the pulling direction operating force is about 250 N. That is, when M is the mass of the transported object, the lateral friction coefficient with respect to the operating force in the pushing direction is preferably μ _s × M <150. Regarding lifting, referring to the fact that women are about 60% of men (see, for example, the Hyogo Ninth Workplace Accident Prevention Promotion Five-Year Plan) The degree is presumed to be desirable.

The friction coefficient of the sliding portion 4 needs to be set so as to satisfy the above-described conditions. For example, as shown in FIG. 6, the lateral friction coefficient is set according to the shape of the outer edge 11 of the sliding portion 4. Can be controlled. Further, the friction coefficient in the lateral direction can be set by the material of the sliding portion 4. That is, by selecting a material that satisfies μ _f <μ _s , it is possible to improve the straight conveyance property.

  Further, in the transport carriage shown in FIG. 2, the friction in the lateral direction can be set by the difference in friction resistance between the central axle and the barrel roller shaft. Moreover, in FIG. 3, the friction of a horizontal direction can be set by using an omnidirectional moving wheel and the conventional caster together. Furthermore, in FIG. 4, the friction in the lateral direction can be increased by increasing the difference in friction between the omnidirectional moving wheels themselves.

  The present invention can be suitably applied to a transport cart provided with casters such as a bed, a stretcher, a luggage transport cart, and a shopping cart.

(A) It is a side view which shows the omnidirectional movement wheel which concerns on the 1st Embodiment of this invention, (b) It is a front view. It is a perspective view which shows the conveyance trolley | bogie which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows the conveyance trolley | bogie which concerns on the 1st modification of the 2nd Embodiment of this invention. It is a perspective view which shows the conveyance trolley | bogie which concerns on the 2nd modification of the 2nd Embodiment of this invention. It is a graph which shows the relationship between the friction coefficient of the longitudinal direction of a sliding part, and the friction coefficient of a transversal direction, and the relationship with linear conveyance property. It is a perspective view which shows embodiment of a sliding part. It is a graph which shows the relationship between the weight of a bed, and operating force. The omnidirectional moving wheel attached to the moving trolley | bogie described in patent document 1 is shown, (a) Side view, (b) Front view. The wheel for omnidirectional mobile vehicles arrange | positioned at the omnidirectional mobile vehicle of patent document 2 is shown, (a) Side view, (b) Front view. It is a perspective view which shows the prior art example of an omnidirectional moving wheel product.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Central axle shaft 2; Frame 3; Barrel type roller 4; Sliding part 5; Conveyance carriage 6; Omni-directional moving wheel 7; Support shaft 8; Base part 9; Traveling direction 10; Contact surface 13; barrel roller shaft 14; screw 120; central axle 121; frame 122; barrel 123; recess 124; barrel shaft 125; acute angle portion 212; drive shaft 214; plate member 215; Barrel type free roller 217; annular member 217a; long side portion 217b; short side portion 218; second barrel type free roller

Claims (8)

A central axle, a frame attached to the central axle, and a barrel-shaped roller shaft that is arranged in a circumferential direction around the central axle in a virtual plane perpendicular to the central axle and orthogonal to the central axle A plurality of barrel rollers pivotally supported by the frame and an outer edge from the central axle together with an outer edge of the barrel roller from the central axle, each being arranged between the barrel rollers in the virtual plane. A sliding portion supported by the frame so as to constitute a peripheral surface of an axle, and the barrel roller and the sliding portion are alternately grounded by rotation around the central axle. It is movable in a first direction, and is movable in a second direction orthogonal to the first direction by rotation of the barrel roller about the barrel roller axis. Directional moving wheels. 2. The omnidirectional movement according to claim 1, wherein a friction coefficient in a circumferential direction around the central axle in the sliding portion is smaller than a friction coefficient in an axial direction of the central axle in the sliding portion. Wheel. 3. The omnidirectional moving wheel according to claim 1, wherein the sliding portion alternately includes a grounding portion and a non-grounding portion along a circumferential direction around the central axle. The same rotary body as the one set of the rotary body composed of the barrel roller and the sliding portion is provided in another virtual plane orthogonal to the central axle, and the two sets of rotary bodies are the barrel roller. The omnidirectionally moving wheels according to any one of claims 1 to 3, wherein the arrangements of these are shifted from each other by a half pitch. The omnidirectional moving wheel according to any one of claims 1 to 4, wherein the barrel roller is made of urethane. The omnidirectional moving wheel according to any one of claims 1 to 5, wherein the sliding portion is made of nylon. 7. The omnidirectional device according to claim 1, wherein an outer edge of the sliding portion centered on the central axle is designed to be smaller than an outer edge of the barrel roller. Moving wheels. A conveying cart comprising the omnidirectional moving wheel according to any one of claims 1 to 6.

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