Conveyor

Abstract

To enable smooth lateral movement in a carrier device using two Mecanum wheels.SOLUTION: A carrier device 1 is attached to a bed 10 equipped with casters and having one end side in a longitudinal direction supported by an operator 100, and moves the bed 10 laterally. The carrier device 1 comprises: first and second Mecanum wheels 21R and 21L; first and second motors 22R and 22L drivingly connected to the first and second Mecanum wheels 21R and 21L, respectively; an operation part 3 to which a movement direction of the bed 10 is input; and a controller 4 for controlling the first and second motors 22R and 22L. When a lateral direction is input to the operation part 3 as the movement direction, the controller 4 operates the first and second Mecanum wheels 21R and 21L through the first and second motors 22R and 22L so as to move the bed 10 laterally in the movement direction input to the operation part 3 while turning it in such a manner that a rotation center Oz is positioned on its one end side.SELECTED DRAWING: Figure 9C

Description

[Technical Field]

[0001] The present disclosure relates to a transport device. [Background technology]

[0002] For example, Patent Document 1 discloses an auxiliary propulsion system that uses Mecanum wheels in its drive units. This auxiliary propulsion system includes a pair of Mecanum wheels connected to a chassis, a motor that drives each Mecanum wheel, and a control system that detects changes in the rotational speed of each motor. The chassis to which each Mecanum wheel is connected has front and rear wheels, and is configured so that force is applied from the rear wheels by the operator when the chassis moves.

[0003] According to Patent Document 1, when the chassis moves laterally (sideways) in a predetermined direction, the operator applies a force in the same direction. When each Mecanum wheel rotates due to the applied force, the resulting change in rotation speed is reported to the control system. Based on this report, the control system starts the electric rotation of the motor. This electric rotation assists the lateral movement of the chassis. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2016-525977 Summary of the Invention [Problem to be solved by the invention]

[0005] When two Mecanum wheels are used as in Patent Document 1, the rotation direction of each wheel is the same when moving laterally along the direction in which the Mecanum wheels are aligned and when turning around the center of the two Mecanum wheels. In this case, if each Mecanum wheel is rotated to assist the lateral movement of the chassis, the lateral movement and turning movement will occur simultaneously.

[0006] Therefore, when the configuration described in Patent Document 1 is used, if a force is applied to the rear wheel of the chassis, for example, in the right direction, the rear wheel side portion will move laterally to the right, but the aforementioned turning motion will occur at the same time, causing the front wheel side portion of the chassis to turn to the left. In this case, the front wheel side portion must be manually swung in the opposite direction, which is inconvenient for achieving smooth lateral movement.

[0007] Furthermore, in a narrow environment such as an elevator, when attempting to move the chassis laterally away from the wall, the part on the front wheel side may rotate in the opposite direction as mentioned above, which may result in a collision between that part and the wall.

[0008] The technology disclosed herein has been made in consideration of these points, and its purpose is to achieve smooth lateral movement in a transport device that uses two Mecanum wheels. [Means for solving the problem]

[0009] A first aspect of the present disclosure relates to a transport device attached to a caster-equipped bed whose longitudinal end is supported by an operator and configured to laterally move the bed. The transport device includes first and second Mecanum wheels attached to a lower portion of the bed, first and second motors drivingly connected to the first and second Mecanum wheels, respectively, an operation unit to which a direction of movement of the bed is input, and a controller for controlling the first and second motors. When a lateral movement direction is input to the operation unit, the controller operates the first and second Mecanum wheels via the first and second motors to rotate the bed so that the center of rotation is located at the one end while moving the bed laterally in the movement direction input to the operation unit.

[0010] According to the first aspect, the center of rotation is closer to one end of the bed than to the other end, so the amount of movement during rotation (particularly the amount of movement in the input movement direction) is smaller than that of the other end. However, because one end of the bed is supported by the operator, the operator's own lateral movement is influenced by the lateral movement of the bed, ensuring sufficient movement for that end as well. This allows both one end and the other end of the bed to move sufficiently, and ultimately the entire bed to move laterally in the desired movement direction. This makes it possible to achieve smooth lateral movement even with a transport device using two Mecanum wheels.

[0011] A second aspect of the present disclosure relates to a transport device attached to a caster-equipped bed and configured to laterally move the bed. The transport device includes first and second Mecanum wheels attached to a lower portion of the bed, first and second motors drivingly connected to the first and second Mecanum wheels, respectively, an operation unit supported on one end of the bed in the longitudinal direction and receiving a direction of movement of the bed, and a controller for controlling the first and second motors. When a direction of movement is input to the operation unit, the controller operates the first and second Mecanum wheels via the first and second motors to rotate the bed so that the center of rotation is located at the one end and move the bed laterally in the direction of movement input to the operation unit.

[0012] According to the second aspect, the operating unit is supported on one end of the bed. Therefore, the operator ends up supporting one end of the bed when operating the operating unit, even without consciously supporting that end. This allows the operator to move laterally, as in the first aspect, ensuring sufficient movement on that end. This allows both one end and the other end of the bed to move sufficiently, ultimately moving the entire bed laterally in the desired direction. This allows smooth lateral movement even with a transport device using two Mecanum wheels.

[0013] According to a third aspect of the present disclosure, the first and second Mecanum wheels may be arranged side by side in the short direction of the bed, and each of the first and second Mecanum wheels may have a wheel body that rotates around an axis of rotation extending in the short direction, and a plurality of barrel-shaped rollers that are arranged along the outer periphery of the wheel body and rotate around inclined axes that are inclined with respect to both the short direction and the long direction, and the inclined axis of the first Mecanum wheel may be inclined with respect to the inclined axis of the second Mecanum wheel so as to be line-symmetrical with respect to the long direction.

[0014] According to the third aspect, by rotating the first Mecanum wheel and the second Mecanum wheel in opposite directions, a thrust that rotates the bed and a thrust that moves the bed laterally are simultaneously generated. The former thrust contributes to generating a rotational movement with the center of rotation located at one end of the bed, while the latter thrust acts favorably to encourage the operator to move laterally. Therefore, the configuration of the third aspect is effective in achieving smooth lateral movement when using two Mecanum wheels.

[0015] Furthermore, according to a fourth aspect of the present disclosure, when a movement direction is input to the operation unit, the controller sets the command rotation speeds of the first and second Mecanum wheels so that one of the wheels rotates forward and the other wheel rotates backward, and when setting the command rotation speeds, the absolute values ​​of the command rotation speeds of the first and second Mecanum wheels are equal.

[0016] According to the fourth aspect, by making the absolute values ​​of the command rotation speed of the first Mecanum wheel and the command rotation speed of the second Mecanum wheel equal, it is possible to achieve lateral movement parallel to the lateral direction. This is effective in achieving smooth lateral movement when using two Mecanum wheels.

[0017] Furthermore, according to a fifth aspect of the present disclosure, a head plate of the bed may be arranged on the one end side, and a foot plate of the bed may be arranged on the other end side located opposite the one end side in the longitudinal direction.

[0018] For example, when transporting a medical bed, the operator usually supports the head plate. Therefore, by placing the head plate on the end where the center of rotation is located during a swiveling motion, the operator can naturally support the end without providing any special markings or indications. This is effective in achieving smooth lateral movement when using two Mecanum wheels. [Effects of the Invention]

[0019] As described above, according to the present disclosure, smooth lateral movement can be achieved in a transport device using two Mecanum wheels. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a side view illustrating an example of the overall configuration of a transport device and a caster-equipped bed. [Figure 2] FIG. 2 is a bottom view illustrating an example of the overall configuration of the transport device and the caster-equipped bed. [Figure 3] FIG. 2 is a perspective view illustrating the configuration of a transport device. [Figure 4] FIG. 2 is a plan view illustrating the configuration of a transport device. [Figure 5] FIG. 2 is a side view illustrating the configuration of a transport device. [Figure 6] FIG. 2 is a block diagram illustrating the configuration of a control system of the transport device. [Figure 7] FIG. 2 is a front view illustrating the configuration of an operation unit. [Figure 8] 10A and 10B are diagrams for explaining the operation of the first and second Mecanum wheels. [Figure 9A] 10A and 10B are diagrams showing a specific example of lateral movement using a transport device. [Figure 9B] 10A and 10B are diagrams showing a specific example of lateral movement using a transport device. [Figure 9C] 10A and 10B are diagrams showing a specific example of lateral movement using a transport device. [Figure 10] 10 is a flowchart illustrating a process related to lateral movement of a bed. [Figure 11] 10A and 10B are diagrams illustrating command rotation speeds of each motor during lateral movement. [Figure 12] FIG. 1 is a diagram showing a conventional example of a conveying device. [Figure 13] FIG. 10 is a diagram showing a modified example of the transport device. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0022] FIG. 1 is a side view illustrating the overall configuration of the transport device 1 and the caster bed 10, and FIG. 2 is a bottom view illustrating the overall configuration of the transport device 1 and the caster bed 10. As shown in FIG.

[0023] 3 is a perspective view illustrating the configuration of the transport device 1, Fig. 4 is a plan view illustrating the configuration of the transport device 1, and Fig. 5 is a side view illustrating the configuration of the transport device 1. Also, Fig. 6 is a block diagram illustrating the configuration of the control system of the transport device 1, Fig. 7 is a front view illustrating the configuration of the operation unit 3, and Fig. 8 is a diagram for explaining the operation of the first and second Mecanum wheels 21R, 21L.

[0024] 1 and 2, a transport device 1 according to this embodiment is attached to a bed with casters (hereinafter simply referred to as a "bed") 10. This bed 10 is equipped with a plurality of casters 14 including front wheels 14F and rear wheels 14B, and is designed to be used as, for example, a medical bed.

[0025] Hereinafter, the longitudinal direction of bed 10, i.e., the direction in which a person lies on bed 10, will be referred to as the "front-to-back direction" or "longitudinal direction," and the side of the front-to-back direction toward the feet will be referred to as the "front," and the other side toward the pillow will be referred to as the "rear."

[0026] Similarly, the short direction of the bed 10, that is, the direction perpendicular to the front-to-rear direction on a horizontal plane, is referred to as the "left-to-right direction" or "lateral direction," and the side of the left-to-right direction that faces the depth of the paper in FIG. 1 is referred to as the "right," and the other side that faces the front of the paper in FIG. 1 is referred to as the "left" (see FIG. 2 for details). The "left-to-right direction" here refers to the left-to-right direction when viewed from the rear to the front. In the following description, "lateral movement" refers to movement along this left-to-right direction. The left-to-right direction (lateral direction) can also be defined as the direction that is perpendicular to the front-to-rear direction and extends along the transport surface F (the floor surface along which the bed 10 travels).

[0027] The bed 10 is configured so that one end side in the front-rear direction (the rear end side in this embodiment) is supported by the operator 100. The transport device 1 is configured so as to move the bed 10 supported by the operator 100 laterally.

[0028] 1, the bed 10 includes a bed body 11 on which a mattress (not shown) is placed, a frame 12 that supports the bed body 11 from below, a lifting unit 13 that raises and lowers the bed body 11 relative to the frame 12, and a plurality of casters 14 (four in the illustrated example) arranged on the underside of the bed 10. When used as a medical bed, the bed 10 weighs, for example, between 60 kg and 300 kg.

[0029] Here, the bed body 11 has a headboard 11h arranged at the rear end side of the bed 10, a footboard 11f arranged at the front end side opposite the rear end side in the front-to-rear direction, and side rails 11s arranged on both the left and right sides of the bed 10.

[0030] Of these, the headboard 11h is supported from the rear by the operator 100 in order to manually move the bed 10. The headboard 11h functions as a support part to which force is applied by the operator 100. Members such as handles and grips may be attached to the headboard 11h or integrated with the headboard 11h, and these members may serve as the support part.

[0031] As shown in FIG. 2, the frame 12 is configured in a rectangular frame shape, and its four sides are formed by a front frame 12F, a right frame 12R, a left frame 12L, and a rear frame 12B.

[0032] Here, the front frame 12F is disposed on the front side of the bed 10 and extends in the left-right direction. The right frame 12R is disposed on the right side of the bed 10 and extends in the front-rear direction. The left frame 12L is disposed on the left side of the bed 10 and extends in the front-rear direction. The rear frame 12B is disposed on the rear side of the bed 10 and extends in the left-right direction.

[0033] 1 and 2, the front wheels 14F and rear wheels 14B that make up the plurality of casters 14 are arranged at the four corners of the underside of the bed 10. Two front wheels 14F and two rear wheels 14B are provided along the left-right direction. The plurality of casters 14 support the frame 12, the lifting section 13, and the bed body 11 on the conveyance surface F.

[0034] Each caster 14 is a so-called free caster and includes a mounting portion 14a fixed to the underside of the bed 10, a fork portion 14b that can rotate about a rotation axis Oc relative to the mounting portion 14a, and a wheel 14c that is rotatably supported by the fork portion 14b. The rotation axis Oc of each fork portion 14b extends in the vertical direction (the height direction of the bed 10). The rotation axis of each wheel 14c extends along a horizontal plane. This rotation axis is tilted in the left-right direction as the fork portion 14b rotates relative to the mounting portion 14a.

[0035] The transport device 1 is disposed so as to bridge between a midpoint in the front-to-rear direction of the right frame 12R and a midpoint in the front-to-rear direction of the left frame L. The transport device 1 is disposed between the front wheels 14F and the rear wheels 14B in the front-to-rear direction, and is disposed in the center of the bed 10 in the left-to-right direction.

[0036] 1 to 6, the transport device 1 includes a storage box 6, a fixture 7, first and second Mecanum wheels 21R, 21L, first and second motors 22R, 22L, an operation unit 3, and a controller 4 (the first and second motors 22R, 22L are only shown in FIG. 6). Hereinafter, of the first and second Mecanum wheels 21R, 21L, the first Mecanum wheel 21R is assumed to be located on the right side, and the second Mecanum wheel 21L is assumed to be located on the left side.

[0037] Of these elements, the controller 4 is housed in the housing box 6, while the mounting fixture 7, the first and second Mecanum wheels 21R, 21L, the first and second motors 22R, 22L, and the operating unit 3 are arranged outside the housing box 6.

[0038] As described above, the storage box 6 stores the controller 4. The storage box 6 is disposed between the first Mecanum wheel 21R and the second Mecanum wheel 21L in the left-right direction.

[0039] The storage box 6 is attached to a fixture 7 together with the first and second Mecanum wheels 21R, 21L, and is attached to the bottom of the bed 10 via this fixture 7. The fixture 7 is detachable from the bottom of the bed 10. In other words, the transport device 1 according to this embodiment can be retrofitted to the bed 10 and can be detached as needed.

[0040] More specifically, as shown in Figures 2 to 5, the mounting fixture 7 according to this embodiment has a front rail member 71f, a rear rail member 71b, and first and second arm members 72R and 72L that rotatably support the first and second Mecanum wheels 21R and 21L, respectively.

[0041] The front rail member 71f and the rear rail member 71b are spaced apart in the front-to-rear direction and span the front-to-rear center of the right frame 12R and the front-to-rear center of the left frame 12L, respectively. The front rail member 71f and the rear rail member 71b are detachable from the right frame 12R and the left frame 12L. The first and second Mecanum wheels 21R, 21L and the storage box 6 are arranged between the front rail member 71f and the rear rail member 71b in the front-to-rear direction.

[0042] 3 and 4, the first arm member 72R is swingably supported by the rear rail member 71b. The front end of the first arm member 72R rotatably supports the first Mecanum wheel 21R. The first arm member 72R is positioned between the first Mecanum wheel 21R and the storage box 6 in the left-right direction.

[0043] One end of a first tension spring 75R is anchored to the upper end of the first arm member 72R, and the other end of the first tension spring 75R is anchored to a first bracket 76R fixed to the front rail member 71f.

[0044] 3 and 4, the second arm member 72L is swingably supported by the rear rail member 71b, similar to the first arm member 72R. The front end of the second arm member 72L rotatably supports the second Mecanum wheel 21L. The second arm member 72L is positioned between the second Mecanum wheel 21L and the storage box 6 in the left-right direction.

[0045] One end of a second tension spring 75L is secured to the upper end of the second arm member 72L, and the other end of the second tension spring 75L is secured to a second bracket 76L fixed to the front rail member 71f (see also FIG. 5).

[0046] As shown in Figures 1 and 2, the first and second Mecanum wheels 21R, 21L are attached to the lower part (bottom) of the bed 10. The first and second Mecanum wheels 21R, 21L are disposed rearward of the front wheels 14F and in front of the rear wheels 14B. As shown in Figure 2, the first and second Mecanum wheels 21R, 21L are disposed so as to be aligned in the left-right direction, which is the short side direction.

[0047] More specifically, as shown in Figures 3 to 5, the first and second Mecanum wheels 21R, 21L each have a wheel body 21a, 21a that rotates around a rotation axis Ox extending in the left-right direction, and a plurality of barrel-shaped rollers 21b, 21b that are arranged along the outer periphery of the wheel body 21a, 21a and rotate around inclined axes Or, OL that are inclined with respect to both the left-right direction and the front-rear direction.

[0048] Here, as shown in Fig. 4, the inclination axis Or of the barrel-shaped roller 21b constituting the first Mecanum wheel 21R (hereinafter also referred to as the "first inclination axis") is inclined to be linearly symmetrical with respect to the inclination axis Ol of the barrel-shaped roller 21b constituting the second Mecanum wheel 21L (hereinafter also referred to as the "second inclination axis"), with the front-rear direction as the reference (see the axis of symmetry Os in Fig. 4). In other words, the first inclination axis Or and the second inclination axis Ol extend in mirror symmetry in a plan view.

[0049] Furthermore, when viewed from above (when viewed from above) as in Figure 4, the inclined axes Or, Ol of each barrel-shaped roller 21b, 21b each extend from the inside to the outside in the left-right direction (from the center in the left-right direction to the right or left) as they move from the rear to the front along the front-to-rear direction.

[0050] Specifically, the first inclined axis Or extends from the center to the right in the left-right direction as it moves from the rear to the front along the front-rear direction, while the second inclined axis Ol extends from the center to the left in the left-right direction as it moves from the rear to the front along the front-rear direction.

[0051] More specifically, the inclination angle θr of the first inclined axis Or relative to the rotation axis Ox is set to 45° in plan view. Similarly, the inclination angle θl of the second inclined axis Ol relative to the rotation axis Ox is also set to 45° in plan view. Note that the inclination direction and angle of each barrel-shaped roller 21b are not limited to these examples.

[0052] As described above, the first and second Mecanum wheels 21R, 21L are connected to each other via the front rail member 71f and the rear rail member 71b shown in Fig. 3 etc. Therefore, the first and second Mecanum wheels 21R, 21L move together in the front-rear and left-right directions and rotate together around a rotation axis perpendicular to the horizontal plane.

[0053] The first and second motors 22R, 22L are drivingly connected to the first and second Mecanum wheels 21R, 21L, respectively. Specifically, the first and second motors 22R, 22L are each configured as a DC brushless motor with an encoder. The first and second motors 22R, 22L are both electrically connected to the controller 4 and are activated by signals input from the controller 4.

[0054] The first motor 22R is connected to the first Mecanum wheel 21R so as to transmit a driving force (torque). The second motor 22L is connected to the second Mecanum wheel 21L so as to transmit a driving force (torque).

[0055] The first motor 22R is built into the first Mecanum wheel 21R, and the second motor 22L is built into the second Mecanum wheel 21L. By building the first and second motors 22R and 22L in this way, the entire conveyance device 1 can be simplified and made compact.

[0056] The operation unit 3 is configured to input the movement direction of the bed 10. The operation unit 3 is a remote controller that accepts input of the movement direction, and is connected to the controller 4 by wire or wirelessly. The movement directions that the operation unit 3 can accept include at least the left-right direction (particularly, both the right and left directions).

[0057] 7, the operation unit 3 according to this embodiment has a right switch 31 that is pressed to instruct lateral movement to the right, and a left switch 32 that is pressed to instruct lateral movement to the left. When the right switch 31 is pressed, the operation unit 3 generates an electrical signal corresponding to the pressing, and when the left switch 32 is pressed, the operation unit 3 generates another electrical signal corresponding to the pressing. The operation unit 3 inputs each of the generated electrical signals to the controller 4.

[0058] Moreover, the operating unit 3 according to this embodiment is configured to be supported on one end of the bed 10 in the front-rear direction. For example, the operating unit 3 shown in FIG. 1 is attached to the headboard 11h at the rear end of the bed 10 (see also FIG. 7). The operating unit 3 may be separate from or integrated with the element that functions as the support, such as the headboard 11h. In the former case, the operating unit 3 may be configured to be engaged with the headboard 11h.

[0059] The controller 4 controls the first and second motors 22R, 22L based on an electrical signal input from the operation unit 3. The controller 4 has a CPU, a memory, and an input / output bus, and is configured by, for example, a control board.

[0060] The controller 4 sets command rotation speeds for the first and second motors 22R, 22L based on electrical signals input from the operation unit 3, and inputs control signals corresponding to the command rotation speeds to the first and second motors 22R, 22L. The first and second motors 22R, 22L rotate at the command rotation speeds set by the controller 4. By changing the sign of the command rotation speeds, the rotation directions of the first motor 22R and the second motor 22L can be changed individually.

[0061] When the first motor 22R rotates, its driving force is transmitted to rotate the first Mecanum wheel 21R. Similarly, when the second motor 22L rotates, its driving force is transmitted to rotate the second Mecanum wheel 21L. At this time, by changing the rotation direction of each motor 22R, 22L as described above, the corresponding Mecanum wheel 21R, 21L can be switched between forward and backward rotation.

[0062] In this embodiment, when the first Mecanum wheel 21R located on the right side is rotated forward, a thrust force can be exerted diagonally forward to the left on the transport device 1 and the bed 10 (arrow A in FIG. 8). 11 On the other hand, when the second Mecanum wheel 21L located on the left side is rotated forward, the transport device 1 can apply a thrust force to the bed 10 diagonally forward to the right (see arrow A in FIG. 8). 12 (See

[0063] 8, for example, when both the first and second Mecanum wheels 21R, 21L are rotated forward, the leftward thrust exerted by the forward rotation of the first Mecanum wheel 21R and the rightward thrust exerted by the forward rotation of the second Mecanum wheel 21L cancel each other out, allowing the entire transport apparatus 1 to exert a forward thrust. This thrust allows the bed 10 to move forward.

[0064] Similarly, when the first Mecanum wheel 21R located on the right side is rotated backward, a thrust force can be exerted on the transport device 1 and the bed 10 obliquely backward to the right (arrow A in FIG. 8). 21 On the other hand, when the second Mecanum wheel 21L located on the left side is rotated backward, the transport device 1 can apply a thrust force to the bed 10 obliquely backward to the left (see arrow A in FIG. 8). 22 (See

[0065] 8, for example, when both the first and second Mecanum wheels 21R, 21L are rotated backward, the rightward thrust exerted by rotating the first Mecanum wheel 21R backward and the leftward thrust exerted by rotating the second Mecanum wheel 21L backward cancel each other out, resulting in a backward thrust being exerted by the entire transport apparatus 1. This thrust allows the bed 10 to move backward.

[0066] On the other hand, the transport device 1 can also apply a thrust force to the bed 10 in the left and right directions by rotating one of the first and second Mecanum wheels 21R, 21L forward and rotating the other backward.

[0067] In the example shown in the lower left of FIG. 8, a thrust force in the right direction is applied to the bed 10 by rotating the first Mecanum wheel 21R backward and rotating the second Mecanum wheel 21L forward.

[0068] However, when one of the first and second Mecanum wheels 21R, 21L is rotated forward and the other is rotated backward, the conveying device 1 will simultaneously apply a thrust to rotate the bed 10 in addition to a thrust to move the bed 10 laterally.

[0069] In the example shown in the lower right of Figure 8, the transport device 1 generates a thrust that rotates the bed 10 to the right by rotating the first Mecanum wheel 21R backward and the second Mecanum wheel 21L forward. In this case, the rotation trajectory R is the same as that of the arrow A mentioned above. 21 and arrow A 12 The bed 10 has an arc shape with a tangent at and the center of the arc, namely, the rotation center Oz, is located on the rear end side of the bed 10. Therefore, the thrust applied to the bed 10 causes the part located on the opposite side of the rotation center Oz (the part on the front end side of the bed 10) to rotate rightward.

[0070] Therefore, by rotating the first Mecanum wheel 21R backward and the second Mecanum wheel 21L forward, both a thrust that rotates the bed 10 to the right so that the center of rotation Oz is located at the rear end of the bed 10 (in other words, a thrust that rotates the front end of the bed 10 to the right), and a thrust that moves the entire bed 10 laterally to the right are applied to the bed 10. In this case, the front end of the bed 10 rotates clockwise around the center of rotation Oz. Due to this rotation, the front end of the bed 10 moves significantly more to the right than the rear end.

[0071] Similarly, although not shown in the figures, by rotating the first Mecanum wheel 21R forward and rotating the second Mecanum wheel 21L backward, both a thrust that rotates the bed 10 to the left so that the center of rotation Oz is located at the rear end of the bed 10 (in other words, a thrust that rotates the front end of the bed 10 to the left), and a thrust that moves the entire bed 10 laterally to the left are applied to the bed 10. In this case, the front end of the bed 10 rotates counterclockwise around the center of rotation Oz. Due to this rotation, the front end of the bed 10 moves farther to the left than the rear end.

[0072] The conveying device 1 according to this embodiment is configured to actively utilize the above-mentioned operations to achieve smooth lateral movement, even when using two Mecanum wheels, in the same way as when using four Mecanum wheels.

[0073] That is, when a left-right movement direction is input to the operation unit 3, the controller 4 of this embodiment rotates the bed 10 so that the center of rotation Oz is located at one end side of the bed 10 (the rear end side in this embodiment), and activates the first and second Mecanum wheels 21R, 21L via the first and second motors 22R, 22L to move the bed 10 laterally in the movement direction input to the operation unit 3 (leftward or rightward).

[0074] In this case, the rear end of the bed 10 has a smaller movement distance in the input movement direction because the rotation center Oz is closer to the rear end than to the other end of the bed 10 (the front end in this embodiment). However, the rear end of the bed 10 is supported by the operator 100. Therefore, the operator 100 is also moved laterally in response to the lateral movement of the bed 10, so that it is possible to ensure a sufficient movement distance for the rear end of the bed 10. This allows both the front and rear ends of the bed 10 to move sufficiently, and ultimately allows the entire bed 10 to move laterally in the desired movement direction.

[0075] Furthermore, when a movement direction is input to the operation unit 3, the controller 4 according to this embodiment sets the command rotation speeds for one of the first and second Mecanum wheels 21R, 21L to rotate forward and the other to rotate backward, and when setting these command rotation speeds, the absolute values ​​of the command rotation speeds for the first Mecanum wheel 21R and the second Mecanum wheel 21L are made equal.

[0076] Specific examples of lateral movement of bed 10 will be described below with reference to Fig. 9A, Fig. 9B, and Fig. 9C. Here, Fig. 9A, Fig. 9B, and Fig. 9C are diagrams showing specific examples of lateral movement using transport device 1. Also, Fig. 12 is a diagram showing a conventional example of a transport device.

[0077] First, as shown in Fig. 9A, a case will be illustrated in which a wall W is located to the left of the operator 100, and the bed 10 is moved laterally to the right from a state where the bed 10 is close to the wall W. In such a case, it is conceivable that a lateral force is applied to the rear end of the bed 10 (for example, the headboard 11h shown in Fig. 1) and the first and second Mecanum wheels 21R, 21L are rotated by detecting the force (a so-called assist method).

[0078] However, when such a force is applied, a pivoting motion occurs around the front end of the bed 10 or the center position of the first and second Mecanum wheels 21R, 21L as the center of rotation Oz', which may cause the front end of the bed 10 (the part on the footboard 11f side) to move toward the wall W (see FIG. 12). In order to prevent the bed 10 from colliding with the wall W, it is advantageous to avoid such movement as much as possible.

[0079] 9A, when the right switch 31 is pressed, the first Mecanum wheel 21R rotates backward and the second Mecanum wheel 21L rotates forward. As a result, a thrust is applied to the bed 10 to rotate it to the right so that the center of rotation Oz is located at the rear end of the bed 10, and a thrust is applied to move the entire bed 10 laterally to the right.

[0080] When the two thrust forces described above are applied to the bed 10, as shown in Fig. 9B, the bed 10 moves to the right overall from the rear end to the front end, while rotating the front end to the right (see arrow Ab in Fig. 9B). The amount of movement at that time is shown as the deviation from the initial position Tr1 indicated by the two-dot chain line. Note that the initial position Tr1 here is a schematic representation of the position of the bed 10 in Fig. 9A.

[0081] As shown in FIG. 9C, the movement and rotation of the bed 10 to the right causes the operator 100 to move to the right, ensuring a rightward movement distance for the rear end of the bed 10 supported by the operator 100 (see arrow Ac in FIG. 9C). By ensuring a movement distance for the front end of the bed 10 through the rotational motion and a movement distance for the rear end of the bed 10 through the movement of the operator 100, the entire bed 10 can be moved laterally to the right. The movement distance is indicated by the deviation from the intermediate position Tr2 indicated by the two-dot chain line. The intermediate position Tr2 here is a schematic representation of the position of the bed 10 in FIG. 9B.

[0082] As a hypothetical configuration, consider a case where the bed 10 is rotated so that the center of rotation Oz' is located at the front end, as shown in the comparative example of FIG. 12. In this case, although the rear end supported by the operator 100 moves significantly laterally, the front end of the bed 10 must be rotated by the operator 100 applying a force in the lateral direction. Because the front end of the bed 10 is farther from the operator 100 than the rear end, the load required for such a movement is relatively large. This is inconvenient for achieving smooth lateral movement.

[0083] Furthermore, if such a hypothetical configuration is adopted, the area near the rotation center Oz' on the front end side of the bed 10 (in the example shown in Figure 12, the left front wheel 14F) may turn in the opposite direction, which could result in that area colliding with a wall W or the like.

[0084] Therefore, configuring the bed 10 so that the center of rotation Oz is located on the rear end side as shown in FIGS. 9A to 9C is effective in reducing the load on the operator 100 and preventing collision with the wall W or the like.

[0085] Next, a specific example of the processing performed by the controller 4 during lateral movement will be described. Here, Fig. 10 is a flowchart illustrating the processing related to the lateral movement of the bed 10, and Fig. 11 is a diagram illustrating the command rotation speeds of each motor during lateral movement (particularly during lateral movement to the right).

[0086] 10, the controller 4 reads in the electrical signals output from the operation unit 3 (various readings). In the following step S2, the controller 4 determines whether or not an operation input to the operation unit 3 has been detected (remote control operation detected?) based on whether or not the electrical signals have been read in step S1.

[0087] If the determination in step S2 is NO, the control process returns. On the other hand, if the determination in step S2 is YES, the control process proceeds to step S3.

[0088] In step S3, the controller 4 increases the command rotation speed of each of the first and second motors 22R and 22L. The magnitude of each command rotation speed increases according to the pressing time of the right switch 31 or the left switch 32. At this time, the absolute value of the command rotation speed of the first motor 22R is set to match the absolute value of the command rotation speed of the second motor 22L. The command rotation speed of the first motor 22R is equal to the command rotation speed of the first Mecanum wheel 21R. The command rotation speed of the second motor 22L is equal to the command rotation speed of the second Mecanum wheel 21L.

[0089] Furthermore, when the first tilt axis Or and the second tilt axis Ol are set as in this embodiment, the command rotation speed of the first motor 22R becomes negative and the command rotation speed of the second motor 22L becomes positive when the right switch 31 is pressed. On the other hand, when the left switch 32 is pressed, the command rotation speed of the first motor 22R becomes positive and the command rotation speed of the second motor 22L becomes negative.

[0090] In this embodiment, the command rotation speed when rotating the first or second Mecanum wheel 21R, 21L forward is set to "positive," and the command rotation speed when rotating the first or second Mecanum wheel 21R, 21L backward is set to "negative."

[0091] In the following step S4, the controller 4 determines whether or not the command rotation speeds of the first and second motors 22R, 22L have reached a predetermined threshold value T. This threshold value T is a preset parameter, and is read from the memory of the controller 4 as appropriate. If the determination is NO, the control process skips step S5 and proceeds to step S6. On the other hand, if the determination is YES in step S4, the control process proceeds to step S6 via step S5.

[0092] In step S5, the controller 4 sets the command rotation speed of each of the first and second motors 22R, 22L to the threshold value T. By the controller 4 executing the process of step S5, the command rotation speed of each of the first and second motors 22R, 22L is limited to a value equal to or less than the threshold value T (see also FIG. 11). Note that the signs of the command rotation speeds in FIG. 11 are merely an example for a lateral movement to the right. In the case of a lateral movement to the left, the positive and negative signs of the command rotation speeds of each of the first and second motors 22R, 22L are reversed relative to the values ​​in FIG. 11.

[0093] In step S6, the controller 4 drives the first and second motors 22R, 22L at the command rotation speeds set in steps S4 and S5. This driving realizes the operation described with reference to FIGS. 9A and 9B. As a result, in the following step S7, the lateral movement of the operator 100 himself is induced. As the operator 100 himself moves laterally, the entire bed 10 moves laterally in the desired direction, as described with reference to FIG. 9C.

[0094] As described above, according to this embodiment, as described with reference to Figures 9A to 9C, by utilizing the operation unique to the use of two Mecanum wheels, it is possible to move both the rear end side of the bed 10 where the rotation center Oz is located and the front end side of the bed 10 located on the opposite side of the rotation center Oz laterally. As a result, even with a transport device using two Mecanum wheels, smooth lateral movement can be achieved, similar to when four Mecanum wheels are used.

[0095] 1 to 2 and 9A to 9C, the operating unit 3 is supported on the rear end of the bed 10. Therefore, when the operator 100 operates the operating unit 3, the operator 100 ends up supporting the rear end of the bed 10 without consciously supporting the rear end of the bed 10. This ensures a sufficient amount of movement for the rear end, similar to when the operator 100 consciously supports the rear end. This allows both the rear and front ends of the bed 10 to move sufficiently, and ultimately allows the entire bed 10 to move laterally in the desired direction. This makes it possible to achieve smooth lateral movement even with a transport device 1 that uses two Mecanum wheels.

[0096] 8 and 10, by rotating the first Mecanum wheel 21R and the second Mecanum wheel 21L in opposite directions, a thrust that rotates the bed 10 and a thrust that moves the bed 10 laterally are simultaneously generated. The former thrust contributes to generating a rotational movement in which the rotation center Oz is located at the rear end of the bed 10, while the latter thrust acts favorably to encourage the operator to move laterally. Therefore, the configuration of the third aspect is effective in realizing smooth lateral movement when two Mecanum wheels are used.

[0097] 10, by making the absolute values ​​of the command rotation speed of the first Mecanum wheel 21R and the command rotation speed of the second Mecanum wheel 21L equal, it is possible to achieve lateral movement parallel to the lateral direction. This is effective in achieving smooth lateral movement when using two Mecanum wheels.

[0098] Furthermore, for example, when transporting a medical bed, the headboard 11h is usually supported by the operator 100. Therefore, by locating the headboard 11h at the rear end where the rotation center Oz is located during a turning operation, the operator 100 can naturally support the rear end without providing any special markings or indications. This is effective in realizing smooth lateral movement when two Mecanum wheels are used.

[0099] <Other embodiments> In the above embodiment, the "one end" supported by the operator 100 and where the center of rotation Oz is located during rotation is the rear end of the bed 10, and the "other end" located opposite in the fore-and-aft direction is the front end of the bed 10, with the operating unit 3 being positioned at the rear end of the former, but the present disclosure is not limited to such a configuration.

[0100] FIG. 13 is a diagram showing a modified example of the transport device 1. As in the modified transport device 1", the "one end" may be the front end of the bed 10, and the "other end" may be the rear end of the bed 10. In this case, the support position for the operator 100 and the mounting position of the operating unit 3 are reversed front to back, and the rotation center Oz" is located at the front end of the bed 10. In this case, the first tilt axis Or" of the first Mecanum wheel 21R" according to the modified example and the second tilt axis Ol" of the second Mecanum wheel 21L" according to the modified example may be tilted from the inside to the outside in the left-right direction as they move from the front end to the rear end of the bed 10. [Explanation of symbols]

[0101] 1. Conveyor device 3 Control section 4 Controller 10 beds 11 Bed body 11h Head Plate 11f Footplate 14 Caster 14F front wheel 14B rear wheel 21R 1st Mecanum Wheel 21L 2nd Mecanum Wheel 21a Wheel body 21b Barrel Roller 22R 1st motor 22L Second motor Oz Rotation Center Or 1st tilt axis Ol 2nd tilt axis

Claims

1. A transport device attached to a bed with casters, one end of which is supported by an operator in the longitudinal direction, and configured to move the bed laterally, First and second Mecanum wheels attached to the bottom of the bed; first and second motors drivingly connected to the first and second Mecanum wheels, respectively; an operation unit into which the direction of movement of the bed is input; a controller that controls the first and second motors, When a lateral movement direction is input to the operation unit, the controller operates the first and second Mecanum wheels via the first and second motors so that a thrust for moving the bed laterally and a thrust for rotating the bed are simultaneously exerted and so that the center of rotation in the rotating operation is located on the one end side. A conveying device characterized by:

2. A transport device attached to a caster-equipped bed and configured to laterally move the bed, comprising: First and second Mecanum wheels attached to the bottom of the bed; first and second motors drivingly connected to the first and second Mecanum wheels, respectively; an operating unit configured to be supported on one end side of the bed in the longitudinal direction, and into which a moving direction of the bed is input; a controller that controls the first and second motors, When a movement direction is input to the operation unit, the controller operates the first and second Mecanum wheels via the first and second motors so that a thrust for moving the bed laterally and a thrust for rotating the bed are simultaneously exerted and the center of rotation in the rotating operation is located on the one end side. A conveying device characterized by:

3. 3. The conveying device according to claim 1 or 2, The first and second Mecanum wheels are arranged side by side in the short direction of the bed, The first and second Mecanum wheels each include: a wheel body that rotates around a rotation axis extending in the short side direction; a plurality of barrel-shaped rollers arranged along the outer periphery of the wheel body, each of which rotates around an inclined axis inclined with respect to both the short-side direction and the long-side direction; The tilt axis of the first Mecanum wheel is tilted so as to be symmetrical with respect to the tilt axis of the second Mecanum wheel with respect to the longitudinal direction. A conveying device characterized by:

4. 4. The conveying device according to claim 3, When a movement direction is input to the operation unit, the controller sets command rotation speeds to rotate one of the first and second Mecanum wheels forward and rotate the other backward, and when setting the command rotation speeds, the absolute values ​​of the command rotation speeds of the first Mecanum wheel and the second Mecanum wheel are made equal. A conveying device characterized by:

5. 3. The conveying device according to claim 1 or 2, A head plate of the bed is disposed on the one end side, The foot plate of the bed is disposed on the other end opposite to the one end in the longitudinal direction. A conveying device characterized by:

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