JP3656500B2 - Omnidirectional cart - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an omnidirectional cart having omnidirectional wheels such as a universal wheel and a ball wheel.
[0002]
[Prior art]
Various types of omnidirectional carts equipped with omnidirectional wheels have been proposed. For example, Japanese Patent Application Laid-Open No. 6-171562 shows a vehicle equipped with omnidirectional wheels that are ball wheels. Japanese Utility Model Publication No. 63-39164 discloses an omnidirectional moving wheel called a universal wheel (all-side roller).
[0003]
[Problems to be solved by the invention]
By the way, in the conventional omnidirectional mobile trolley, the omnidirectional moving wheel that can individually apply the driving force when the omnidirectional moving wheel can be moved in any direction by applying the driving force to the omnidirectional moving wheel. 3 or more were combined.
[0004]
For this reason, the cost is inevitably high.
[0005]
The present invention has been made in view of these points, and the object of the present invention is to move the wheel in substantially any direction even though there are two omnidirectional wheels that can apply driving force. It is in providing an omnidirectional mobile trolley that can be made inexpensive.
[0006]
[Means for Solving the Problems]
Thus, the omnidirectional cart according to the present invention includes an operation handle held by an operator, two omnidirectional wheels that can be individually applied with driving force, and at least one universal wheel. An omnidirectional carriage provided on a carriage, and two omnidirectional wheels to which driving force is applied are arranged on the outer periphery of a frame that can freely rotate around the central axle to which driving force is applied. It is a universal wheel with a plurality of barrels that can rotate around an axis that is perpendicular to the direction and radial direction, and is arranged so that the intersection of the driving direction is on the side far from the operation handle across the center of gravity of the carriage. It has the feature in being.
[0007]
Since there are only two omnidirectional wheels, the cost can be reduced, and there are only two omnidirectional wheels for driving. It can be complemented by an operation by an operator holding the operation handle, and a universal wheel type omnidirectional moving wheel is used, and the intersection of the drive direction comes to the far side of the operation vehicle from the center of gravity of the carriage. Therefore, the operation is also easy.
[0008]
An omnidirectional moving wheel can be suitably used as the above-mentioned free wheel, and in particular, the free wheel can rotate around the central axle, and can rotate around the axis at the outer periphery and orthogonal to the axial direction and the radial direction of the central axle. In the case of a universal wheel consisting of a plurality of barrels, the forward / backward direction by two omnidirectionally moving wheels capable of applying a driving force and the rotational direction around the central axle of the universal wheel are shifted. It is good to leave. You may make it make the back-and-forth advance direction by the two omnidirectional movement wheels which can provide a driving force, and the rotation direction around the axis | shaft of the central axle of the universal wheel which is a universal wheel orthogonally cross.
[0009]
The operating handle is provided with a detecting means for detecting the operating force applied by the operator so that the driving force applied to the omnidirectional moving wheel corresponds to the operating force detected by the detecting means. In this case, the operation becomes easy.
[0010]
At this time, the operating handle is provided with a detecting means and a moving direction indicating switch for applying a driving force in the right and left moving direction to the two omnidirectional moving wheels in preference to the driving force control by the detecting means. And a selection switch for restricting the operation of the driving force control by the detecting means in a plurality of ways. However, the detecting means applies the operating forces in the front, rear, left, right, and rotation directions applied to the operating handle. Of course, it may be detected.
[0011]
Further, it is preferable to provide a braking means for applying a brake by grounding on the operation handle side of the omnidirectional moving wheel to which the driving force is applied.
[0012]
If the operating wheel, the omnidirectionally moving wheel, and the free wheel are provided on the layout vehicle, a layout vehicle having excellent operability can be obtained.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on an example of an embodiment. As shown in FIG. 1, this carriage 1 has omnidirectional moving wheels 2a, 2b on the left and right of the front end side, and casters on the left and right of the rear end side. , And an operation handle 4 that can be gripped by an operator 9 and applied to the rear end face.
[0014]
The omnidirectional wheels 2 a and 2 b are of the universal wheel type shown in FIG. 2, and the universal wheel omnidirectional wheels 2 a and 2 b are connected to the outer periphery of the frame 21 having the central axle 20 with the central axle 20. A plurality of barrels 22 that are rotatable around an axis orthogonal to the axial direction and the radial direction are arranged, and the outer shape of the longitudinal section including the support shaft of each barrel 22 forms an arc centered on the central axle 20. Therefore, the omnidirectional moving wheels 2a and 2b can move in all directions by rotation around the central axle 20 and rotation around the respective axes of the barrels 22. The plurality of barrels 22 are provided in two rows, and the positions of the barrels 22 around the central axle 20 are shifted by a half pitch in both rows so that the barrel 22 can always be grounded. Yes.
[0015]
The two omnidirectional moving wheels 2a, 2b can receive a driving force around the central axle 20 by the motors 25a, 25b being connected to the central axles 20, 20 respectively. Further, two omnidirectionally moving wheels 2 a and 2 b arranged on the left and right sides of the front end side of the carriage 1 have their axial extension lines of the central axles 20 and 20 intersecting at a portion near the center of the carriage 1. Thus, it is attached to the carriage 1 in a state where it is swung left and right from the front-rear direction.
[0016]
The operation handle 4 disposed on the rear end surface of the carriage 1 has a shape that is long in the left-right direction so that the operator can easily apply a force in the left-right direction by grasping with both hands, and two switches SW1, SW2 are attached. ing. Of the two-switch momentary switches SW1 and SW2, the switch SW1 is for forward and backward movement, and the switch SW2 is for left and right movement. As shown in FIG. If the motors 25a, 25b and the omnidirectional moving wheels 2a, 2b are rotated forward to move the carriage 1 forward and the switch SW1 is switched to the reverse side, the motors 25a, 25b and the omnidirectional moving wheels 2a, 2b are reversed. The carriage 1 is moved backward.
[0017]
Further, if the switch SW2 is switched to one side, the motor 25a rotates in the forward direction and the motor 25b rotates in the reverse direction. If the switch SW2 is switched to the other side, the motor 25a rotates in the reverse direction and the motor 25b rotates in the normal direction. In order to move the cart 1 to the left or right, it is only necessary to apply a force in the direction to be moved to the operation handle 4 while switching the switch SW2. If the switch SW1 is also operated while operating the switch SW2, an operation in which the left / right movement and the forward / backward movement operation are combined can be obtained.
[0018]
Here, the lateral force is also applied to the operation handle 4 when moving left and right, because the two omnidirectional moving wheels 2a and 2b exhibiting driving force are on the front end side of the carriage 1 and the turning operation is centered on the rear end side. This is to correct this. In addition, if the force applied to the operation handle 4 is set in the direction opposite to the moving direction generated by the rotation of the omnidirectional moving wheels 2a and 2b, the carriage 1 can be turned slightly. Further, as shown in FIG. 4, the intersection point x in the driving direction of the two omnidirectional moving wheels 2 should be located farther from the operation handle 4 across the center of gravity G of the carriage 1. The operation of turning and moving left and right becomes easy.
[0019]
The motors 25a and 25b of the omnidirectional moving wheels 2a and 2b are driven not according to the operation of the switches SW1 and SW2 but according to the operation force applied to the operation handle 4 by the operator as shown in FIG. Also good. In this case, the longitudinal force (propulsion force) fx, the lateral force (lateral movement force) fy, and the moment fψ applied to the operation handle 4 can be detected. These forces act as Fx, Fy, Fψ at the center of gravity G position of the carriage 1, but if the distance from the center of gravity G to the operation handle 4 is L,
Fx = fx Fy = fy Fψ = fψ + fy · L
Thus, the outputs fl, fr of the motors 25a, 25b are determined from the assist gains Kx, Ky, Kψ for these forces Fx, Fy, Fψ.
[0020]
Assuming that the motor force for assisting the propulsive force Fx is flx, frx, the motor force for assisting the lateral movement force Fy is fly, fry, and the motor force for assisting the moment force Fψ is flψ, frψ. The outputs of 25a and 25b are (flx + frx) · cos θ = Kx · Fx = Kx · fx with respect to the propulsion direction.
For the lateral movement direction,
(Fly-fly) · sin θ = Ky · Fy = Kx · fy
For the moment force, if the distance from the center of gravity G to the omnidirectional moving wheels 2a, 2b is dx, dy,
(−flψ + frψ) · (dy · cos θ + dx · sin θ) = Kψ · Fψ
= Kψ · (fψ + fy · L)
It becomes. The motor outputs fl and fr are
fl = flx + fly + flψ
fr = frx + fry + frψ
Ask for.
[0021]
FIG. 6 shows an example of the configuration of the operation handle 4 that can detect the operation forces fx, fy, and fψ, and is movable in the left-right direction by leaf springs 41, 41 on the rear end surface of the carriage 1. Both ends of the operation handle 4 are connected to the base 40 via leaf springs 42, 42. The operation handle 4 is movable back and forth by bending the leaf spring 42 with respect to the base 40. Here, the non-contact distance sensor 45 is opposed to the detected portion 44 provided on the base 40, and the amount of bending of the leaf spring 41 when the lateral force is applied to the operation handle 4 is determined in the lateral direction of the base 40. , And the non-contact distance sensors 46 and 46 are made to face the leaf springs 42 to detect the amount of bending of the leaf springs 42 and 42, and the non-contact distance sensors 45, 46 and 46 are detected. The operation forces fx, fy, and fψ are obtained from the output.
[0022]
Further, the obtained operating force fx, fy, fψ the assist gain Kx, Ky, from the value of Kpusai, motor 25a, the output fl of 25b, calculates the fr, the motors 25a calculated value through the motor driver, the driving of 25b Do.
[0023]
If the control of the motors 25a and 25b at this time is torque control, the output changes according to the operated force, so that a natural movement for the operator can be obtained, and a speed detection device such as an encoder can be used. There is an advantage that it is not necessary, but when speed control is used, since the speed is controlled according to the operated force, there is an advantage that the operation feeling is constant even when the load fluctuation is large, acceleration control In this case, the operational feeling is constant even when the load fluctuation is large, and a natural operational feeling similar to that during torque control can be obtained.
[0024]
Only one universal wheel 3 may be provided on the operation handle 4 side. Further, in the above example, the caster-type universal wheel 3 is used. However, the caster-type universal wheel 3 in which the vertical rotation axis of the horizontal rotation and the grounding point are deviated depends on the direction and the moving direction of the carriage 1. When the two wheels do not match, sometimes the direction of the carriage 1 must be reversed by 180 ° in the initial stage of movement, and a large operating force is required at this time. 3 may be constituted by an omnidirectional moving wheel such as a ball wheel or a universal wheel. A smooth operation can be obtained when the carriage 1 is moved in any direction.
[0025]
When only one universal wheel-type omnidirectional moving wheel as described above is used as the universal wheel 3, as shown in FIG. 8, two omnidirectional moving wheels 2a, The forward / backward direction by 2b and the rotational direction around the central axle of the universal wheel, which is the universal wheel 3, may be orthogonal to each other. As shown in FIG. 9, when the rotation direction of the free wheel 3 around the central axle 20 and the forward / rearward direction coincide with each other, even if a brake 26 for applying braking to the rotation around the central axle 20 is provided, the free wheel 3. Since the barrel 22 can freely rotate about the axis, the movement of the rear end of the carriage 1 in the left-right direction (the movement in the left-right direction around the point X in the figure) cannot be stopped. In this way, the longitudinal movement can be stopped by the motors 25a and 25b for driving the two omnidirectional moving wheels 2a and 2b, and the lateral movement can be stopped by the free wheel 3. If each barrel 22 of the universal wheel 3 is provided with a brake, the movement of the carriage 1 can be stopped without the orthogonal arrangement as described above, but this is very difficult due to the structure. Not practical.
[0026]
However, when the carriage 1 has to overcome a step when moving forward and backward, the universal wheel type free wheel 3 arranged in the above-mentioned orthogonal direction can only get over a very small step as shown in FIG. From the viewpoint of getting over, it is preferable that the rotation direction of the free wheel 3 around the central axle 20 coincides with the forward / backward direction.
[0027]
For this purpose, when the universal wheel type free wheel 3 is used, in practice, as shown in FIG. 11, the rotation direction of the two or one free wheel 3 around the central axle 20 is changed to the omnidirectional moving wheel 2a. , 2b may be shifted from the forward / backward direction. It is possible to suppress left and right runout centering on the point A in the figure while ensuring the step-over capability.
[0028]
When the brake is provided, a lift-up type that stops the movement of the carriage 1 by grounding on the side where the universal wheel 3 of the carriage 1 is provided, that is, the rear end side, is not applied to the rotation of the universal wheel 3. A brake (for example, a pedal lock) may be provided. It is inexpensive and can be braked reliably.
[0029]
By the way, when the omnidirectional moving wheels 2a and 2b are driven according to the operating force applied to the operating handle 4, the motors 25a and 25b are output by multiplying the operating forces fx, fy and fψ by the assist gains Kx, Ky and Kψ. In other words, when the operation handle 4 is pulled, it moves backward, when the operation handle 4 is pushed, it moves forward, when the operation handle 4 is moved left and right, it moves left and right, and the operation handle 4 is pushed on one side and pulled on one side. For example, when the turning operation is performed by the difference between the left and right outputs, the carriage 1 can be moved in the desired direction simply by operating the operation handle 4, but due to the high degree of freedom. The movement of the carriage 1 may cause wobbling. In particular, although it is desired to move in the width direction to the left and right, the left and right ends of the operation handle 4 cannot be equally applied to the left and right ends, which may cause a turning operation.
[0030]
For this purpose, the above-mentioned two-contact momentary type switch SW2 is provided, and as shown in FIG. 12, when the switch SW2 is not operated, operation control according to the force applied to the operation handle 4 is performed. When SW2 is operated to select leftward or rightward movement, whatever output is applied to the operation handle 4, the selected output for leftward movement or rightward movement is the motor. It is also preferable to obtain it from 25a, 25b.
[0031]
Further, in the driving force control according to the operating force applied to the operation handle 4 instead of the switch SW2 that designates the moving direction, the operation is restricted in a plurality of ways as shown in FIG. A selection switch SW may be provided. For example, as shown in the example, a state where only forward / backward movement according to the applied operation force can be performed, a state where only a turning operation according to the applied operation force can be performed, and a left / right movement according to the applied operation force It is possible to switch between the state in which only the operation can be performed. You may switch to the state which can perform both advancing and turning according to operation force, and the state which can perform a left-right movement according to operation force.
[0032]
By the way, the said trolley | bogie 1 can be applied suitably for the allocation vehicle used for the allocation in a hospital etc. A modern multifunctional vehicle equipped with a heating / cooling function is heavy, and it is a place where the operation place is a hospital with many physically vulnerable people. Can satisfy this requirement.
[0033]
【The invention's effect】
As described above, the present invention includes an operation handle held by an operator, two omnidirectional wheels that can individually apply driving force, and at least one universal wheel. Therefore, only two omnidirectional wheels are required for driving wheels, and the cost can be reduced. In addition, there are only two omnidirectional wheels for driving. It can be supplemented by the operation of the operator holding the handle, and the omnidirectional moving wheel, which is the drive wheel, is composed of a universal wheel. Since they are arranged so that the intersections come, the operations of turning and right-and-left movement are easy and practically not a problem.
[0034]
It is preferable to use an omnidirectional moving wheel as the universal wheel because it can always move smoothly in an arbitrary direction.
[0035]
Further, in the case where the universal wheel is a universal wheel comprising a rotation around the central axle and a plurality of barrels on the outer peripheral portion and rotatable around an axis perpendicular to the axial direction and the radial direction of the central axle, By shifting the forward / backward direction by the two omnidirectional moving wheels to which driving force can be applied and the rotational direction around the central axle of the universal wheel, the left and right sides Shake can be suppressed. In particular, if the forward / backward direction by two omnidirectional moving wheels that can be applied with driving force and the rotational direction around the central axle of the universal wheel, which is a universal wheel, are orthogonal to each other, Although it is inferior, it is possible to suppress left and right run-out only by a brake that suppresses rotation around the central axle.
[0036]
The operating handle is provided with a detecting means for detecting the operating force applied by the operator so that the driving force applied to the omnidirectional moving wheel corresponds to the operating force detected by the detecting means. In this case, it is possible to obtain an operation that is easy and has an excellent operational feeling.
[0037]
At this time, if the operating handle is provided with a detecting means and a moving direction indicating switch for applying a driving force in the left and right moving direction to the two omnidirectional moving wheels in preference to the driving force control by the detecting means, Can be easily moved in the width direction.
[0038]
Further, even if a detection unit and a selection switch that restricts a plurality of operations at the time of driving force control by the detection unit are provided, it is possible to move in a desired direction without wobbling.
[0039]
If the detection means detects the front / rear / right / left and rotation three-axis operation force applied to the operation handle, it can obtain any movement according to the operation force. be able to.
[0040]
Providing reliable braking at low cost can be achieved by providing braking means for braking by grounding on the operation handle side of the omnidirectional moving wheel to which driving force is applied.
[0041]
If the steering wheel is provided with an operation handle, an omnidirectionally moving wheel, and a free wheel, it is possible to obtain a trolley with excellent operability.
FIG. 1 is a schematic plan view of an example of an embodiment of the present invention.
FIG. 2 shows the same omnidirectional wheel, in which (a) is a side view and (b) is a front view.
FIG. 3 is a diagram for explaining the operation of the drive motor for the omnidirectional wheel according to the first embodiment.
FIG. 4 is a schematic plan view of the above.
FIG. 5 is a schematic plan view of another example.
FIG. 6 is a horizontal sectional view of the operation handle portion of the above.
FIG. 7 is a schematic plan view of still another example.
FIG. 8 is a schematic plan view of another example.
FIG. 9 is a schematic plan view of still another example.
FIGS. 10A and 10B are a side view and a front view showing the relationship between an omnidirectional moving wheel and a step.
FIGS. 11A and 11B are schematic plan views of other examples, respectively.
FIG. 12 is a flowchart of an example of a control system.
FIG. 13 is a flowchart of another example of the control system.
[Explanation of symbols]
1 dolly 2a, 2b omnidirectional wheel 3 free wheel 4 operation handle

Claims (10)

An omnidirectional movement type carriage provided with an operation handle held by an operator, two omnidirectional movement wheels capable of individually applying a driving force, and at least one universal wheel . Two omnidirectional wheels to which driving force is applied can rotate around the axis perpendicular to the axial direction and radial direction of the central axle on the outer periphery of the frame that can rotate around the central axle to which driving force is applied An omnidirectional mobile trolley characterized by a universal wheel with a plurality of barrels and an intersection of drive directions on the far side of the trolley across the center of gravity of the trolley.   2. The omnidirectional cart according to claim 1, wherein the universal wheel is an omnidirectional wheel.   The universal wheel is a universal wheel that has a plurality of barrels that can rotate around the axis perpendicular to the axial direction and the radial direction of the central axle on the outer periphery of the frame that can rotate around the central axle. The omnidirectional mobile trolley according to claim 2, wherein the forward / backward direction of the two omnidirectional wheels that can be moved is shifted from the rotational direction of the universal wheel about the central axle.   4. The forward / backward direction of the two omnidirectionally movable wheels capable of applying a driving force and the rotational direction around the central axle of the universal wheel, which is a universal wheel, are orthogonal to each other. Omnidirectional mobile trolley.   The operating handle is provided with detecting means for detecting the operating force applied by the operator, and the driving force applied to the omnidirectional moving wheel is in accordance with the operating force detected by the detecting means. The omnidirectional mobile trolley according to any one of claims 1 to 4.   The operation handle is provided with a detecting means and a moving direction indicating switch for applying a driving force in the left-right moving direction to the two omnidirectional moving wheels in preference to the driving force control by the detecting means. The omnidirectional cart according to claim 5.   6. The omnidirectional mobile trolley according to claim 5, wherein the operation handle is provided with a detecting means and a selection switch for restricting a plurality of operations when the driving force is controlled by the detecting means.   6. The omnidirectional mobile trolley as claimed in claim 5, wherein the detecting means detects an operating force applied to the operating handle in the front, rear, left, right, and rotation directions of three axes.   The omnidirectional mobile type according to any one of claims 1 to 8, further comprising braking means for applying a brake by grounding closer to an operation handle than an omnidirectional mobile wheel to which a driving force is applied. Trolley.   The omnidirectional mobile trolley according to any one of claims 1 to 9, characterized in that an operating handle, an omnidirectional mobile wheel, and a free wheel are provided on the arrangement vehicle.

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