JP2021156407A - Spherical acceleration/deceleration machine and control method for spherical acceleration/deceleration machine - Google Patents

Abstract

To provide a spherical acceleration/deceleration machine capable of efficiently transmitting rotation of a rotor around an axis line connecting centers of a rotor of a spherical motor and an output ball to which the rotation of the rotor is transmitted, to the output ball, and an effective control method for the spherical acceleration/deceleration machine.SOLUTION: The present invention relates to a spherical acceleration/deceleration machine 1 which comprises a spherical motor 2 and an output ball 8 and rotates the output ball 8 by transmitting rotation of a rotor 3 of the spherical motor 2 to the output ball 8. The spherical acceleration/deceleration machine comprises a plurality of rotation transmission balls 6A and 6B which is rotated with the rotation of the rotor 3 and rotates the output ball 8. The spherical acceleration/deceleration machine 1 comprises rotation suppression mechanisms 7 which are provided so as to be freely rotatable around any axis line within an orthogonal plane P passing centers OA and OB of the rotation transmission balls 6A and 6B and being orthogonal to a virtual transmission axis line C when an axis line connecting centers O3 and O8 of the rotor 3 and the output ball 8 is defined as the virtual transmission axis line C, and are configured to suppress the rotation around a parallel axis line CP in parallel with the virtual transmission axis line C.SELECTED DRAWING: Figure 1

Description

The present invention relates to a spherical accelerator / reducer and a method for controlling a spherical accelerator / reducer.

Conventionally, motors having various mechanisms have been used. These motors usually operate as a one-degree-of-freedom system. Therefore, for example, when constructing a manipulator having three degrees of freedom, it is necessary to connect and arrange the motors in series at at least three places at the root, the tip and the intermediate position between the manipulators. In such a configuration, since the error of each motor is accumulated at the tip position of the manipulator, it is not easy to control with high accuracy.
Spherical motors have been researched and developed as motors to solve this problem. Spherical motors include wire-towed spherical motors that pull and rotate spheres with wires, piezoelectric spherical motors that use piezoelectric elements, and induced spherical motors that rotate spheres by an induced current generated by rotating a magnetic field with respect to the sphere of a conductor. Various types have been developed, such as an electromagnetic spherical motor that rotates a sphere by attracting a permanent magnet provided on the sphere with an electromagnet. For example, an electromagnetic spherical motor includes a stator having a spherical recess and a spherical rotor that fits within the recess. A plurality of permanent magnets are provided on the surface of the rotor, and a plurality of electromagnets are provided on the wall surface of the recess of the stator. By passing an electric current through an arbitrary electromagnet of the stator and attracting the permanent magnet of the rotor, the rotor can be rotated in an arbitrary direction and at an arbitrary speed.
One spherical motor having such a configuration operates as a three-degree-of-freedom system. That is, since the structure is such that the rotation centers of the rotation axes coincide with each other, the attitude control is easy, and the error can be reduced even when the above-mentioned manipulator is realized. In addition, when a normal motor realizes a three-degree-of-freedom system, three motors are required, but in the case of a spherical motor, one unit can realize a three-degree-of-freedom system. It is possible to reduce the size and weight.
Patent Document 1 discloses such a spherical motor.

Regarding the above spherical motor, when it is desired to improve the torque of the spherical motor and output it, an output sphere having a radius larger than the radius of the rotor is provided, and the rotation of the rotor is transmitted to the output sphere to rotate the output sphere. The spherical speed reducer may be configured so as to take out the output from the output sphere. Further, when it is desired to increase the rotation speed of the spherical motor to output it, an output sphere having a radius smaller than the radius of the rotor is provided and the rotation of the rotor is transmitted to the output sphere to form a spherical speed increaser. Is also possible.
An example of a conventional spherical speed reducer is shown in FIG.
In the spherical speed reducer 100 shown in FIG. 8, a rotation transmission ball 103 is provided so as to abut each of the rotor 101 and the output ball 102. The rotation transmission ball 103 rotates with the rotation of the rotor 101, transmits the rotation to the output ball 102, and rotates the output ball 102. When the axis connecting the center O101 of the rotor 101 and the center O102 of the output sphere 102 is the virtual transmission axis C100, the rotation transmission sphere 103 sets the center O103 so that the center O103 is located on the virtual transmission axis C100. It is rotatably provided around an arbitrary axis that passes through.
In such a configuration, for example, the rotor 101 is rotated counterclockwise around the center O101 in a plane constituting the paper surface, as shown as the direction D101. In this case, due to the frictional force acting between the rotor 101 and the rotation transmission sphere 103, the rotation transmission sphere 103 that abuts on the rotor 101 rotates clockwise about the center O103 as shown as the direction D103. .. Along with this, the output sphere 102 that comes into contact with the rotation transmission sphere 103 rotates counterclockwise about the center O102, as shown as the direction D102.

Another example of the conventional spherical speed reducer is shown in FIG.
Similarly to the spherical speed reducer 100 of FIG. 8, the spherical speed reducer 110 shown in FIG. 9 is also provided with a rotation transmission ball 113 so as to come into contact with each of the rotor 111 and the output ball 112. In the spherical speed reducer 110, two rotation transmission balls 113A and 113B are provided so that their centers O113A and O113B are located away from the virtual transmission axis C110. Each rotation transmission ball 113 is rotatably provided about an arbitrary axis passing through the centers O113A and O113B.
Even in such a configuration, when the rotor 111 rotates as shown in the direction D111, the rotation transmission balls 113A and 113B rotate in the direction D113, which is transmitted to the output sphere 112, and the output sphere 112 rotates in the direction D112. do.

JP-A-2009-5550

In the spherical speed reducers 100 and 110 shown in FIGS. 8 and 9, the rotation of the rotors 101 and 111 around the virtual transmission axes C100 and C110 is difficult to be transmitted to the output balls 102 and 112.
For example, in the spherical speed reducer 100 of FIG. 8, the virtual transmission axis C100 passes through the centers O101 and O103 of the rotor 101 and the rotation transmission ball 103, and at the contact point P101 between the rotor 101 and the rotation transmission ball 103. It is orthogonal to the tangent plane. Therefore, even if the rotor 101 rotates around the virtual transmission axis C100 in, for example, the direction D104, this rotation acts in the direction in which the rotation transmission sphere 103 is to be twisted at the contact P101, so that the rotor 101 and the rotation transmission sphere 103 The frictional force does not sufficiently act between the two, and the rotation is not sufficiently transmitted to the rotation transmission ball 103.

Further, in the spherical speed reducer 110 of FIG. 9, when the rotor 111 rotates around the virtual transmission axis C110 in the direction D114, for example, the rotation transmission ball 113A located on the right side of the paper surface rotates as shown in the direction D115, for example. .. This direction D115 is rotation about the axis C111 passing through the centers O112 and O113A of the output sphere 112 and the rotation transmission sphere 113A.
Here, the axis C111 is orthogonal to the tangent plane at the contact point P112 of the output sphere 112 and the rotation transmission sphere 113A. Therefore, even if the rotation transmission sphere 113A rotates in the direction D115 about the axis C111, this rotation acts in the direction of twisting the output sphere 112 at the contact P112, so that the rotation transmission sphere 113A and the output sphere 112 The frictional force does not act sufficiently between them, and the rotation is not sufficiently transmitted to the output ball 112.
Similarly, it is difficult for the rotation transmission ball 113B located on the left side of the paper surface to sufficiently transmit the rotation of the rotor 111 about the virtual transmission axis C110 to the output ball 112.

The problem to be solved by the present invention is to efficiently transmit the rotation of the rotor around the axis connecting the centers of the rotor of the spherical motor and the output sphere to which the rotation of the rotor is transmitted to the output sphere. It is to provide a possible spherical accelerator / reducer and an effective control method of the spherical accelerator / reducer.

The present invention employs the following means in order to solve the above problems. That is, the present invention is a spherical acceleration / deceleration machine including a spherical motor and an output sphere, which transmits the rotation of the rotor of the spherical motor to the output sphere to rotate the output sphere, wherein the rotor and the output sphere are rotated. It is a sphere provided in contact with each of the above, and includes a plurality of rotation transmission spheres that rotate with the rotation of the rotor and rotate the output sphere, and each of the plurality of rotation transmission spheres is the rotor and the said. When the axis connecting the centers of the output spheres is a virtual transmission axis, a plurality of rotatably provided around an arbitrary axis in an orthogonal plane passing through the center of the rotation transmission sphere and orthogonal to the virtual transmission axis. Provided is a spherical accelerator / reducer provided with a rotation suppression mechanism that suppresses rotation of each of the rotation transmission spheres around a parallel axis that passes through the center of the rotation transmission sphere and is parallel to the virtual transmission axis.

Further, the present invention is a control method for a spherical accelerator / reducer, comprising a spherical motor and an output sphere, and transmitting the rotation of the rotor of the spherical motor to the output sphere to rotate the output sphere. The speed machine is a spherical surface provided in contact with each of the rotor and the output sphere, and includes a plurality of rotation transmission spheres that rotate with the rotation of the rotor and rotate the output sphere, and the plurality of rotations thereof. Each of the transmission spheres is arbitrary in an orthogonal plane passing through the center of the rotation transmission sphere and orthogonal to the virtual transmission axis when the axis connecting the centers of the rotor and the output sphere is used as the virtual transmission axis. A rotation suppression mechanism is provided that is rotatably provided around the axis and suppresses rotation of each of the plurality of rotation transmission spheres around a parallel axis that passes through the center of the rotation transmission sphere and is parallel to the virtual transmission axis. The rotor and the output sphere of the rotor are based on the acceleration / deceleration ratio of the rotation centered on an arbitrary axis in the orthogonal plane and the acceleration / deceleration ratio of the rotation centered on the virtual transmission axis. Provided is a control method of a spherical accelerator / reducer that rotates the output ball by adjusting a rotation direction and a rotation speed.

According to the present invention, a spherical surface capable of efficiently transmitting the rotation of the rotor around the axis connecting the centers of the rotor of the spherical motor and the output sphere to which the rotation of the rotor is transmitted to the output sphere. It is possible to provide an accelerator and a speed reducer and an effective control method for the spherical speed reducer.

It is a schematic side view of the spherical accelerator / reducer in embodiment of this invention. It is a top view of the said spherical accelerator / reducer in a state excluding an output sphere. It is an enlarged view of the B arrow view part of FIG. It is explanatory drawing explaining the transmission of the rotation of the spherical accelerator / reducer. It is explanatory drawing explaining the torque transmission of the said spherical speed booster. It is a flowchart explaining the control method of the said spherical accelerator / reducer. It is a top view of the spherical accelerator / reducer which concerns on the modification of the said Embodiment in the state which removed the output sphere. It is explanatory drawing of the conventional spherical acceleration / reduction machine. It is explanatory drawing of the conventional spherical acceleration / reduction machine.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic side view of the spherical accelerator / reducer according to the present embodiment. FIG. 2 is a plan view of the spherical accelerator / reducer shown in FIG. 1 in a state where the output sphere is removed, and is a cross-sectional view of a portion AA of FIG.
The spherical accelerator 1 includes a spherical motor 2, a support plate 5, rotation transmission balls 6A and 6B, a rotation suppression mechanism 7, an output ball 8, and a control device (not shown).
The spherical motor 2 includes a rotor 3. The rotor 3 is a sphere having a shape, and is provided on a support base (not shown) so as to be rotatable around the center O3. The rotor 3 is controlled by a control device described later so as to rotate about the center O3 in an arbitrary direction and at an arbitrary speed.
The spherical motor 2 may be of any type that drives the rotor 3 by any method. For example, the spherical motor 2 includes a wire-towed spherical motor that pulls and rotates a sphere with a wire, a piezoelectric spherical motor that uses a piezoelectric element, and an induced spherical surface that rotates a sphere by an induced current generated by rotating a magnetic field with respect to the sphere of a conductor. It may be either a motor or an electromagnetic spherical motor in which a permanent magnet provided on a sphere is attracted by an electromagnet to rotate the sphere, or a type other than the above may be used.

A plate-shaped support plate 5 is horizontally provided above the spherical motor 2. The support plate 5 is fixed to a support base or the like by a support member (not shown).
The support plate 5 is provided with a plurality of holes 5a. In this embodiment, two holes 5a are provided. The plurality of holes 5a are provided at symmetrical positions with respect to the center O3 of the rotor 3 when viewed in a plan view as shown in FIG. In the present embodiment, the two holes 5a are provided so as to be separated from each other in the horizontal direction (x-axis direction).

The rotation transmission spheres 6A and 6B are spheres having a radius smaller than that of the rotor 3 in the present embodiment. The rotation transmission balls 6A and 6B are provided with a number corresponding to the number of holes 5a in the support plate 5. That is, in this embodiment, two rotation transmission balls 6A and 6B are provided. Each of the rotation transmission balls 6A and 6B is housed inside the hole 5a corresponding to each of the plurality of holes 5a, and the lower side is by the rotor 3 and the side is the rotation suppression mechanism 7 described below. It is supported and positioned by. The centers OA and OB of the rotation transmission balls 6A and 6B are provided at the same horizontal positions as the support plate 5.

A plurality of rotation suppressing mechanisms 7 are provided for each of the rotation transmitting spheres 6A and 6B, particularly four in the present embodiment. The rotation suppression mechanism 7 is a rotating body that rotates about the rotation axis C7. In particular, in the present embodiment, the rotation suppressing mechanism 7 is a roller. Each rotation suppressing mechanism 7 is provided so that the peripheral surface at a position having the largest radius of gyration about the rotation axis C7 abuts on the corresponding rotation transmission spheres 6A and 6B.

The output sphere 8 is a sphere having a radius larger than that of the rotor 3 in the present embodiment. The output sphere 8 is provided above the rotation transmission spheres 6A and 6B so as to abut on each of the rotation transmission spheres 6A and 6B. The output sphere 8 is shown at a position above each of the rotation transmission spheres 6A and 6B and, for example, the rotation transmission spheres 6A and 6B so as not to interfere with the rotation of the output sphere 8 around the center O8. It is supported by a support member that is not.
In the present embodiment, the center O8 of the output ball 8 is located above the center O3 of the rotor 3 in the vertical direction. As will be described later, since the rotation of the rotor 3 is transmitted to the output sphere 8 via the rotation transmission spheres 6A and 6B, the axis connecting the rotor 3 and the centers O3 and O8 of the output sphere 8 is a virtual transmission axis. Called C. The virtual transmission axis C extends in the z-axis direction, that is, in the vertical direction, which is orthogonal to both the x-axis direction in which the rotation transmission spheres 6A and 6B are separated from each other and the y-axis direction orthogonal to the x-axis direction in the horizontal plane. Exists.

Each of the rotor 3, the rotation transmission balls 6A and 6B, and the output ball 8 is formed of, for example, resin or the like. The surfaces of the rotor 3, the rotation transmission balls 6A and 6B, and the output ball 8 are surface-treated by, for example, coating a material having a high coefficient of friction or processing the surface into a rough surface.
Further, at the contact points between the rotation transmission balls 6A and 6B and the output balls 8, the output balls 8 are appropriately pressed against the rotation transmission balls 6A and 6B by the gravity acting on the output balls 8. Further, at the contact point between the rotation transmission balls 6A and 6B and the rotor 3, the rotation transmission balls 6A and 6B are appropriately pressed against the rotor 3 by the gravity acting on the rotation transmission balls 6A and 6B.
As a result, a frictional force is generated between the rotor 3 and the rotation transmission balls 6A and 6B, and between the rotation transmission balls 6A and 6B and the output ball 8. Therefore, when the rotor 3 rotates around the center O3, the rotation transmission balls 6A and 6B rotate around the centers OA and OB accordingly, and the output sphere 8 rotates around the center O8.
In the present embodiment, as described above, the radius of the output sphere 8 is larger than the radius of the rotor 3. Therefore, the rotation speed of the output ball 8 is slower than the rotation speed of the rotor 3, and the torque of the output ball 8 is higher than the torque of the rotor 3. Therefore, the spherical speed reducer 1 in the present embodiment is a spherical speed reducer.

Here, the rotation axis C7 of each rotation suppression mechanism 7 extends in an orthogonal plane P that passes through the centers OA and OB of the rotation transmission spheres 6A and 6B and is orthogonal to the virtual transmission axis C. The rotation axis C7 of each rotation suppression mechanism 7 is orthogonal to the axis CV connecting the contact points P6 of the rotation suppression mechanisms 7 with the corresponding rotation transmission balls 6A and 6B and the centers OA and OB of the rotation transmission balls 6A and 6B. It is provided. Therefore, each rotation suppressing mechanism 7 does not rotate around an axis parallel to the z-axis.
In such a configuration, for example, when the rotation transmission sphere 6A tries to rotate around the axis parallel to the x-axis through the center OA, the rotation suppression mechanism 7 located above and below the rotation transmission sphere 6A in FIG. 2 moves around the rotation axis. It rotates and does not interfere with the rotation of the rotation transmission ball 6A. Further, in the rotation suppressing mechanism 7 located to the left and right of the rotation transmitting sphere 6A, the rotation of the rotation transmitting sphere 6A acts in the direction of twisting the rotation suppressing mechanism 7 at the contact P6, so that the rotation transmitting sphere 6A and the rotation suppressing mechanism No frictional force acts between 7 and therefore does not interfere with the rotation of the rotation transmission ball 6A. In this way, since none of the rotation suppressing mechanisms 7 hinders the rotation of the rotation transmitting sphere 6A around the axis that passes through the center OA and is parallel to the x-axis, the rotation transmitting sphere 6A freely rotates around the x-axis.
For the same reason, the rotation transmission sphere 6A freely rotates around the axis parallel to the y-axis through the center OA. Further, the rotation transmission sphere 6A freely rotates around an arbitrary axis extending between the x-axis and the y-axis through the center OA.
That is, each of the rotation transmission spheres 6A and 6B is rotatably provided around an arbitrary axis in the orthogonal plane P with the centers OA and OB as the centers.

Further, when each of the rotation transmission spheres 6A and 6B tries to rotate around the parallel axis CP parallel to the virtual transmission axis C, which extends in the z-axis direction through the centers OA and OB, the rotation suppression mechanism 7 moves to the z-axis. Since it does not rotate around, this rotation is suppressed by friction with the rotation suppressing mechanism 7 and stopped. That is, the rotation of each of the rotation transmission balls 6A and 6B around the parallel axis CP is suppressed by the rotation suppressing mechanism 7. As a result, the rotation transmission balls 6A and 6B are provided so as not to rotate around the parallel axis CP.
Hereinafter, when it is described that the spheres of the rotor 3, the rotation transmission spheres 6A, 6B, and the output sphere 8 rotate around axes such as the x-axis, y-axis, and z-axis, these spheres are parallel to the axis. Indicates that the rotation is centered on the axis passing through the centers O3, OA, OB, and O8.

Next, the operation of the spherical accelerator 1 will be described, in particular, the transmission of rotation from the rotor 3 to the output ball 8. The rotation of the rotor 3 is transmitted by each of the rotation transmission spheres 6A and 6B, but since the transmission principle of the rotation transmission sphere 6A and the rotation transmission sphere 6B is the same, in the following description, mainly in FIG. The case where the rotation is transmitted by the rotation transmission ball 6A provided on the right side of the paper surface will be described, and the description of the rotation transmission ball 6B provided on the left side of the paper surface will be omitted.

モーメントのｚ軸方向の成分Ｔ_ｚに関しては、回転伝達球６Ａが中心ＯＡを中心としてｚ軸周りに回転しようとすると回転抑制機構７との摩擦による反作用の力で釣り合って動かないため、回転伝達球６Ａの回転に寄与するのは、モーメントのｙ軸方向の成分Ｔ_ｙのみである。したがって、図３に示されるように力Ｆが加えられた場合には、回転伝達球６Ａは中心ＯＡを中心として、ｙ軸周りに回転する。 FIG. 3 is an enlarged view of the portion seen by the arrow B in FIG. As shown in FIG. 3, consider a case where a force F is applied to the rotation transmission sphere 6A in the x-axis direction perpendicular to the paper surface. The magnitude T of the moment applied around the center OA of the rotation transmission sphere 6A is expressed by the following equation 1 assuming that the distance from the axis of rotation to the point where the force F is applied, that is, the radius of the rotation transmission sphere 6A is R. Will be done.

_{Regarding the component T z in} the z-axis direction of the moment, when the rotation transmission sphere 6A tries to rotate around the z-axis around the center OA, it does not move in balance due to the reaction force due to friction with the rotation suppression mechanism 7, so that the rotation is transmitted. Only _{the component T y} of the moment in the y-axis direction contributes to the rotation of the sphere 6A. Therefore, when a force F is applied as shown in FIG. 3, the rotation transmission sphere 6A rotates about the y-axis with the center OA as the center.

速度成分ｖ_ｉは、ロータ３の、中心Ｏ３を通りｙ軸に平行な軸線周りの回転によっても表現できる。すなわち、ロータ３のｙ軸周りの回転の角速度をω_ｉｙ、ロータ３の半径をＲ_ｉとすると、速度成分ｖ_ｉは、次の式３で表される。

FIG. 4 is an explanatory diagram illustrating the transmission of rotation of the spherical accelerator / reducer.
First, the transmission of rotation around the y-axis by the rotation transmission sphere 6A will be described.
As in Figure 4, at the point of contact between the rotor 3 rotation transmitting ball 6A, when the velocity component in the vertical x-axis direction to the paper surface was v _i, the rotation transmitting ball. 6A around a center OA, rotated around y axis do. The angular velocity of rotation around the y-axis is ω _m , the radius of the rotation transmission sphere 6A is R _m , and the angle formed by the line connecting the center O3 of the rotor 3 and the center OA of the rotation transmission sphere 6A with respect to the virtual transmission axis C is φ. When the velocity component v _i is expressed by the following equation 2.

Velocity component v _i is the rotor 3 can be expressed by rotation about axes parallel to the street y axis center O3. That is, the rotation of the angular velocity omega _iy around y-axis of the rotor _3, and the radius of the rotor 3 and R _i, the velocity components v _i is expressed by the following equation 3.

これら式２〜式５により、次の式６が導き出せる。

Likewise rotation radius R _o of the output ball _8, the output balls 8, angular velocity omega _oy rotation about an axis parallel to the street y axis center _O8, to the virtual transmission axis C, the center O8 output sphere 8 _{Assuming that the angle formed by the line connecting the center OA of the transmission sphere 6A is θ, the velocity component vo} in the x-axis direction perpendicular to the paper surface at the contact point between the output sphere 8 and the rotation transmission sphere 6A is expressed by the following equations 4 and 5. It is represented by.

The following equation 6 can be derived from these equations 2 to 5.

Regarding the transmission of rotation around the x-axis by the rotation transmission sphere 6A, the rotation of the gear when the rotor 3, the rotation transmission sphere 6A, and the output sphere 8 are viewed in a plan view and each of them is regarded as a gear as shown in FIG. It is considered to be the same as the speed transmission ratio. Therefore, the angular velocity of rotation of the rotor 3 around the axis passing through the center O3 and parallel to the x-axis is ω _ix , and the angular velocity of rotation of the output sphere 8 around the axis passing through the center O8 and parallel to the x-axis is ω _ox . Then, the following equation 7 holds.

As already described, the radius R _o of the output ball 8 is greater than the radius R _i of the rotor 3. _{Therefore, the angular velocity ω ox} of the rotation of the output sphere 8 around the x-axis _{and the angular velocity ω oy} of the rotation around the y-axis _{are both the angular velocity ω ix} of the rotation of the rotor 3 around the x-axis and the rotation around the y-axis. It is a value decelerated at the same reduction ratio than the angular velocity ω _{ii of.}
Further, the symbols on the left side and the right side of the equation 7 are the same, and therefore, the output sphere 8 rotates in the same direction as the rotor 3 when rotating around the x-axis and the y-axis.

Next, the behavior when the rotor 3 rotates around the z-axis, that is, about the virtual transmission axis C will be described.
Conceptually, when the rotor 3 rotates around the z-axis, the rotation-transmitting sphere 6A does not rotate around the parallel axis CP that passes through the center OA and is parallel to the z-axis with respect to the rotation-transmitting sphere 6A that abuts on the rotor 3. Because it is provided in, it is transmitted as a rotation around an axis extending in the orthogonal plane P.
The rotation of the rotation transmission sphere 6A around the axis extending in the orthogonal plane P is transmitted to the output sphere 8.
Here, when there is only one rotation transmission sphere 6A, a force acts on the output sphere 8 only at the contact point with the rotation transmission sphere 6A deviated from the virtual transmission axis C, so that the output sphere 8 The rotation of is unstable. However, the spherical accelerator 1 has a rotation transmission ball 6B in addition to the rotation transmission ball 6A. Although not particularly described, since the rotation transmission sphere 6B is provided with the same configuration as the rotation transmission sphere 6A, the rotation transmission sphere 6A is viewed with the virtual transmission axis C as the center based on the same principle as the rotation transmission sphere 6A. Rotates in the same direction of rotation as. That is, since the output sphere 8 is in contact with the two rotation transmission spheres 6A and 6B that rotate in the same rotation direction when viewed from the virtual transmission axis C as the center, the output sphere 8 is virtually transmitted at two different points. When viewed around the axis C, a force that rotates in the same direction acts. As a result, the rotation of the output sphere 8 does not become unstable, and the output sphere 8 rotates about the virtual transmission axis C.

For example, as shown in FIG. 4, the rotor 3 is shown as the direction D3, the portion on the left side of the virtual transmission axis C reaches the right side of the virtual transmission axis C via the front side of the paper surface of the virtual transmission axis C, and the virtual transmission is achieved. Consider a case where the axis C rotates in a direction of returning to the original position from the back side of the paper surface.
Along with this rotation, the rotation transmission sphere 6A located on the right side of the virtual transmission axis C and abutting on the rotor 3 has a portion above the orthogonal plane P passing through the front side of the paper surface as shown as the direction D6A. It reaches below the orthogonal plane P and rotates in a direction of returning to the original position from the back side of the paper surface.
Similarly, the rotation transmission ball 6B located on the left side of the virtual transmission axis C and abutting on the rotor 3 has a portion below the orthogonal plane P passing through the front side of the paper surface as shown as the direction D6B. It reaches above the orthogonal plane P and rotates in a direction of returning to the original position from the back side of the paper surface.
As the rotation transmission spheres 6A and 6B rotate, the output sphere 8 has a portion on the right side of the virtual transmission axis C via the front side of the paper surface of the virtual transmission axis C as shown as the direction D8. It reaches the left side of C and rotates in a direction that returns to the original position from the back side of the paper surface of the virtual transmission axis C.
In this way, when the rotor 3 rotates about the z-axis, the output ball 8 rotates about the z-axis in the direction D8 opposite to the direction D3 in which the rotor 3 rotates.

ここで、回転伝達球６Ａに関しては、上記のようにｚ軸周りには回転せず、直交平面Ｐ内に延在する軸線周りに回転するため、例えばこれをｙ軸とすると、上記の式２、式４が成立する。
したがって、式２、式４、式８、式９により、次の式１０が導き出せる。

Regarding the transmission of rotation around the z-axis by the rotation transmission sphere 6A as described above, the angular velocity of rotation around the axis of the rotor 3 passing through the center O3 and parallel to the z-axis is ω _iz , and the center O8 of the output sphere 8 is set. _Assuming that the angular velocity of rotation around the axis parallel to the z-axis is ω oz, the following equations 8 and 9 hold for the rotor 3 and the output sphere 8.

Here, the rotation transmission sphere 6A does not rotate around the z-axis as described above, but rotates around an axis extending in the orthogonal plane P. Therefore, for example, assuming that this is the y-axis, the above equation 2 , Equation 4 holds.
Therefore, the following equation 10 can be derived from the equations 2, 4, 8, and 9.

Comparing Equations 6 and 7 with Equation 10, it can be seen that the reduction ratio in the transmission of rotation around the z-axis is different from the transmission ratio in the transmission of rotation around the x-axis and y-axis.
Further, the symbols on the left side and the right side of Equation 10 are different. Therefore, when the output sphere 8 rotates about the z-axis, it rotates in a direction opposite to that of the rotor 3, as described above.

Next, the transmission of torque by the rotation transmission ball 6A will be described. FIG. 5 is an explanatory diagram illustrating the transmission of torque of the spherical accelerator / reducer.
Regarding the transmission of torque around the y-axis by the rotation transmission sphere 6A, the moment of rotation around the axis of the rotor 3 passing through the center O3 and parallel to the y-axis is _Tyy , and the output sphere 8 passes through the center O8 to the y-axis. rotation of the moment T _oy about parallel _axes, F _mi the force transmitted to the rotor 3 from rotating transfer spheres _6A, the force transmitted to the rotation transmitting ball 6A from the rotor 3 F _im, transmitted from the rotation transmission balls 6A in the output sphere 8 the force _{F mo,} when the force transmitted to the rotation transmitting ball 6A from the output balls 8 and _{F om,} rotation transmitting ball 6A, 6B from the two is, by considering the balance of moment, the following equation 11 formula 13 Is established.

したがって、式１１〜式１４より、次の式１５、式１６が導き出せる。

Here, the relationship of the following equation 14 is established for each force F _mi , F _im , F _mo , and _Fom.

Therefore, the following equations 15 and 16 can be derived from the equations 11 to 14.

Regarding the transmission of rotation around the x-axis by the rotation transmission sphere 6A, as in the case of the rotation speed, when the rotor 3, the rotation transmission sphere 6A, and the output sphere 8 are viewed in a plan view and each of them is regarded as a gear, It is considered to be the same as the transmission ratio of gears. Therefore, the moment of rotation of the rotor 3 around the axis passing through the center O3 and parallel to the x-axis is _Tix , and the moment of rotation of the output sphere 8 around the axis passing through the center O8 and parallel to the x-axis is _Tox . Then, the following equation 17 is established.

As already described, the radius R _o of the output ball 8 is greater than the radius R _i of the rotor 3. Therefore, the rotation moment T _ox about the x axis of the output ball _8, and the moment T _oy rotation about the y-axis are both moment T _ix rotation about the x-axis of the rotor _3, and a rotation about y-axis It is a value amplified at the same ratio than the moment T _{yy of.} That is, in the x-axis direction and the y-axis direction, the torque of the rotor 3 is amplified and transmitted to the output ball 8. This amplification ratio is the reciprocal of the reduction ratio in Equations 6 and 7.

回転速度の場合と同様に、回転伝達球６Ａはｚ軸周りには回転せず、直交平面Ｐ内に延在する軸線周りに回転するため、ｙ軸の場合と同様に式１２が成立する。したがって、式１２、式１４、式１８、式１９により、次の式２０、式２１が導き出せる。

On the other hand, regarding the transmission of rotation around the z-axis by the rotation transmission sphere 6A, the moment of rotation around the axis of the rotor 3 passing through the center O3 and parallel to the z-axis is _Tiz , and the output sphere 8 passes through the center O8. _Assuming that the moment of rotation around the axis parallel to the axis is Toz, the following equations 18 and 19 are established.

As in the case of the rotation speed, the rotation transmission sphere 6A does not rotate around the z-axis but rotates around the axis extending in the orthogonal plane P, so that the equation 12 holds as in the case of the y-axis. Therefore, the following equations 20 and 21 can be derived from the equations 12, 14, 18, and 19.

Comparing Equations 16 and 17 with Equation 21, it can be seen that the torque amplification ratio in the transmission of rotation around the z-axis is different from the amplification ratio in the transmission of rotation around the x-axis and y-axis. This amplification ratio is the reciprocal of the reduction ratio in Equation 10.
As shown in Equations 10 and 21, in the spherical accelerator 1, the rotation of the rotor 3 around the z-axis, that is, around the virtual transmission axis C is surely transmitted to the output ball 8.

As described above, the reduction ratio of the rotation speed (torque amplification ratio) has different values depending on the components in the x-axis direction, the y-axis direction, and the z-axis direction. Therefore, in order to rotate the output ball 8 in a desired direction and at a desired speed, the rotation direction and rotation speed of the rotor 3 must be set in consideration of reduction ratios and the like that differ in these axial directions. It doesn't become.
The control device controls the rotation direction and rotation speed of the rotor 3 in consideration of such a reduction ratio.

A radius R _o of the output ball 8 radius R _m sum value A of the rotation transmitting ball 6A, the sum of the radius R _m of the radius R _i of the rotor 3 rotation transmitting ball 6A and value B, the rotation from the virtual transmission axis C Assuming that the distance of the transmission sphere 6A to the center OA is L, the following equation 22 holds.

この値Ｋにより、式１０と式２１は、次の式２４、式２５のように表すことができる。

Here, the value K is defined as in the following equation 23.

With this value K, equations 10 and 21 can be expressed as the following equations 24 and 25.

The above equations 6, 7, 16, 16, 17, 24, and 25 are simply expressed as the following equations 26 and 27 by matrix representation.

That is, when rotating the output ball 8, Equation 26 the value to be realized as an angular velocity and torque of the output ball 8, the formula _{27 ω ox, ω oy, ω} oz, T ox, T oy, as _{T oz} It may be input and determined by calculating the rotation speed, rotation direction, and torque of the rotor 3.
In this way, the control device has a reduction ratio (acceleration / reduction ratio) of rotation of the rotor 3 and the output sphere 8 centered on an arbitrary axis in the orthogonal plane P, and a deceleration of rotation centered on the virtual transmission axis C. Based on the ratio (acceleration / deceleration ratio), the rotation direction and rotation speed of the rotor 3 are adjusted to rotate the output ball 8.

Next, the control method of the spherical accelerator 1 will be described with reference to FIGS. 1 to 5 and 6. FIG. 6 is a flowchart of a control method for the spherical accelerator / reducer 1.
For example, when the spherical motor 2 is an electromagnetic spherical motor, the control device is an information processing device such as a personal computer, and the rotation direction and rotation of the rotor 3 are determined by software and programs executed by the CPU in the information processing device. It may be configured to adjust the speed. For example, when the spherical motor 2 itself already includes a control device for controlling the rotation of the rotor 3, the control device may also be used as a control device for the spherical accelerator 1.
Here, the control method is described assuming that the control method is realized as software and a program in this way. However, in reality, the control device does not have to be realized by the information processing device. The control device may be configured by some physical mechanism or mechanism capable of realizing a control method as described below, whereby the rotation direction and rotation speed of the rotor 3 may be controlled.

When the control is started (step S1), the angular velocity and torque for rotating the output ball 8 are acquired and determined (step S3).
Next, the determined angular velocity and torque of the output ball 8 are substituted into the equations 26 and 27, and the angular velocity and torque of the rotor 3 are calculated and determined (step S5).
The rotation of the rotor 3 is controlled based on the angular velocity and torque of the rotor 3 determined in this way (step S7).
It is determined at any time whether to end the rotation of the output ball 8 and stop it (step S9), and if it is determined to end (Yes in step S9), the process ends (step S11). If not (No in step S9), the process proceeds to step S3 and the process is continued.

Next, the effects of the spherical accelerator 1 and the control method of the spherical accelerator 1 will be described.

The spherical accelerator 1 of the present embodiment is a spherical accelerator 1 comprising a spherical motor 2 and an output sphere 8 and transmitting the rotation of the rotor 3 of the spherical motor 2 to the output sphere 8 to rotate the output sphere 8. It is a sphere provided in contact with each of the rotor 3 and the output sphere 8, and is provided with a plurality of rotation transmission spheres 6A and 6B that rotate with the rotation of the rotor 3 and rotate the output sphere 8. Each of the rotation transmission spheres 6A and 6B passes through the centers OA and OB of the rotation transmission spheres 6A and 6B when the axis connecting the centers O3 and O8 of the rotor 3 and the output sphere 8 is set as the virtual transmission axis C. It is rotatably provided around an arbitrary axis in the orthogonal plane P orthogonal to the virtual transmission axis C, and passes through the centers OA and OB of the rotation transmission spheres 6A and 6B, respectively. A rotation suppressing mechanism 7 for suppressing rotation around a parallel axis CP parallel to the virtual transmission axis C is provided.
According to the above configuration, when the rotor 3 rotates around the virtual transmission axis C, the virtual transmission axis C of the rotation transmission sphere 6A centered on the center OA with respect to the rotation transmission sphere 6A that abuts on the rotor 3. Since the rotation around the parallel axis CP parallel to is suppressed by the rotation suppressing mechanism 7, it is transmitted as the rotation around the axis extending in the orthogonal plane P.
The rotation of the rotation transmission sphere 6A around the axis extending in the orthogonal plane P is transmitted to the output sphere 8.
Here, when there is only one rotation transmission ball 6A, the rotation of the output ball 8 becomes unstable. However, the spherical accelerator 1 has a plurality of rotation transmission balls 6A and 6B. The rotation transmission sphere 6B rotates in the same rotation direction as the rotation transmission sphere 6A when viewed with the virtual transmission axis C as the center, based on the same principle as the rotation transmission sphere 6A. That is, since the output sphere 8 is in contact with a plurality of rotation transmission spheres 6A and 6B that rotate in the same rotation direction when viewed with the virtual transmission axis C as the center, the output sphere 8 is virtual at a plurality of different points. When viewed around the transmission axis C, a force that rotates in the same direction acts. As a result, the rotation of the output sphere 8 does not become unstable, and the output sphere 8 rotates about the virtual transmission axis C.
As described above, in the spherical acceleration / deceleration machine 1, the rotation of the rotor 3 about the virtual transmission axis C can be efficiently transmitted to the output ball 8.

Further, the rotation suppressing mechanism 7 is a rotating body provided so as to individually contact each of the plurality of rotation transmitting spheres 6A and 6B, and the rotation axis C7 of the rotating body extends in the orthogonal plane P. It is provided orthogonal to the axis CV connecting the center of the rotation transmission balls 6A and 6B corresponding to the rotating body and the contact point P6 with the rotation transmission balls 6A and 6B.
According to the above configuration, each of the plurality of rotation transmission spheres 6A and 6B passes through the centers OA and OB of the rotation transmission spheres 6A and 6B and is an arbitrary axis in the orthogonal plane P orthogonal to the virtual transmission axis C. It is possible to efficiently realize a structure that is rotatably provided around the rotation transmission spheres 6A and 6B and suppresses rotation around the parallel axis CP that passes through the centers OA and OB and is parallel to the virtual transmission axis C.

Further, a plurality of rotation suppressing mechanisms (rotating bodies) 7 are provided for one rotation transmitting sphere 6A and 6B.
Further, the rotation suppressing mechanism (rotating body) 7 is a roller.
According to the above configuration, the spherical accelerator 1 can be appropriately realized.

Further, a control device for controlling the rotation direction and rotation speed of the rotor 3 is further provided, and the control device is a reduction ratio (increase / decrease) of rotation of the rotor 3 and the output sphere 8 around an arbitrary axis in the orthogonal plane P. The output ball 8 is rotated by adjusting the rotation direction and rotation speed of the rotor 3 based on the speed ratio) and the reduction ratio (acceleration / reduction ratio) of rotation centered on the virtual transmission axis C.
According to the above configuration, when the reduction ratio of the rotation of the rotor 3 and the output sphere 8 around an arbitrary axis in the orthogonal plane P and the reduction ratio of the rotation around the virtual transmission axis C are different. Even so, the output ball 8 can be rotated in a desired rotation direction and rotation speed by controlling the rotation direction and rotation speed of the rotor 3.

Further, the control method of the spherical accelerator 1 of the present embodiment includes a spherical motor 2 and an output sphere 8, and transmits the rotation of the rotor 3 of the spherical motor 2 to the output sphere 8 to rotate the output sphere 8. A control method for the accelerator 1 is that the spherical accelerator 1 is a sphere provided in contact with each of the rotor 3 and the output sphere 8, and rotates with the rotation of the rotor 3 to cause the output sphere 8 to rotate. When a plurality of rotation transmission spheres 6A and 6B to be rotated are provided, and each of the plurality of rotation transmission spheres 6A and 6B has a virtual transmission axis C as an axis connecting the centers O3 and O8 of the rotor 3 and the output sphere 8. , Each of the plurality of rotation transmission spheres 6A and 6B is rotatably provided around an arbitrary axis in the orthogonal plane P passing through the centers OA and OB of the rotation transmission spheres 6A and 6B and orthogonal to the virtual transmission axis C. A rotation suppression mechanism 7 for suppressing rotation around a parallel axis CP that passes through the centers OA and OB of the rotation transmission spheres 6A and 6B and is parallel to the virtual transmission axis C is provided, and the rotor 3 and the output sphere 8 are orthogonal to each other. Rotation direction and rotation of the rotor 3 based on the reduction ratio (acceleration / deceleration ratio) of rotation centered on an arbitrary axis in the plane P and the reduction ratio (acceleration / deceleration ratio) of rotation centered on the virtual transmission axis C. The speed is adjusted to rotate the output sphere 8.
As described above, the spherical accelerator 1 used in the above method can efficiently transmit the rotation of the rotor 3 about the virtual transmission axis C to the output ball 8.
In this spherical accelerator 1, the reduction ratio of rotation of the rotor 3 and the output ball 8 around an arbitrary axis in the orthogonal plane P is different from the reduction ratio of rotation around the virtual transmission axis C. By controlling the rotation direction and rotation speed of the rotor 3, the output ball 8 can be rotated in a desired rotation direction and rotation speed.

The control method of the spherical accelerator 1 and the spherical accelerator 1 of the present invention is not limited to the above-described embodiment described with reference to the drawings, and various other modifications are made within the technical scope thereof. Can be considered.

For example, in the above embodiment, the radius of the output sphere 8 is larger than the radius of the rotor 3, and the spherical speed reducer 1 reduces the rotational speed of the rotor 3 and amplifies the torque to output. It was a spherical speed reducer transmitted to the ball 8, but it is not limited to this.
For example, by making the radius of the output ball 8 smaller than the radius of the rotor 3, the spherical accelerator / reducer is realized as a spherical accelerator in which the rotation speed of the rotor 3 is increased and the torque is attenuated. You can also do it.
In this case, in the description of the above embodiment, the same description as that of the above embodiment can be made by reading the reduction ratio of the rotation speed as the acceleration ratio and the torque amplification ratio as the damping ratio.

Further, in the above embodiment, the virtual transmission axis C is provided so as to coincide with the vertical direction, but it goes without saying that the present invention is not limited to this. That is, a force is applied so that the rotor 3, the rotation transmission spheres 6A and 6B, and the output sphere 8 are crimped to each other without being separated from each other, and a sufficient frictional force acts between them. Then, the spherical accelerator / reducer can be arranged by tilting it in an arbitrary direction or reversing it in the vertical direction.
In this case, in the description of the above-described embodiment, the same description as that of the above-described embodiment can be made by tilting the virtual transmission axis C and the z-axis so as to correspond to the tilt of the spherical accelerator / reducer.

Further, in the above embodiment, the two rotation transmission balls 6A and 6B are provided at symmetrical positions with respect to the virtual transmission axis C, but the present invention is not limited to this. FIG. 7 is a modified example of the arrangement of the rotation transmission spheres. As shown in FIG. 7, even if the three rotation transmission spheres 6C, 6D, and 6E are arranged so as to form an equilateral triangle with the virtual transmission axis C as the center when viewed from the direction of the virtual transmission axis C. good.
Alternatively, four or more rotation transmission balls may be provided.
When three or more rotation transmission spheres are provided in this way, even if the rotor 3 or the output sphere 8 is not in contact with the rotor 3 or the output sphere 8 due to, for example, a displacement of one rotation transmission sphere, the rotor is provided by another rotation transmission sphere. The rotation of 3 can be normally transmitted to the output ball 8.
Further, for example, when two rotation transmission spheres are provided, these two rotation transmission spheres do not necessarily have to be in symmetrical positions with respect to the virtual transmission axis C. For example, two rotation transmission spheres may be provided at positions separated from each other by an angle other than 180 ° about the virtual transmission axis C.
In the above embodiment, the radii of the rotation transmission balls 6A and 6B are smaller than the radius of the rotor 3, but in principle, they may be larger than the radius of the rotor 3.

Further, in the above embodiment, four rotation suppression mechanisms 7 are provided for each rotation transmission sphere 6A and 6B, but the number of rotation suppression mechanisms 7 is not limited to this and may be three. However, it may be 5 or more.
In principle, the rotation suppression mechanism 7 is for suppressing the rotation of the rotation transmission sphere around the parallel axis CP, so one is sufficient. However, in this case, the position of the rotation transmission sphere in the hole 5a of the support plate 5 is not determined. Therefore, the rotation transmission sphere may be supported by providing a sphere that can rotate in an arbitrary direction at two or more other positions. The same applies when there are two rotation suppression mechanisms 7.
Further, the rotation suppressing mechanism 7, that is, the rotating body may be a disk, an annular body in which the inside of the disk is partially hollowed out, or the like. Alternatively, as the rotation suppressing mechanism 7, a roller, a disk, an annular body, or the like may be used in combination.

In addition to this, as long as the gist of the present invention is not deviated, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate.

1 Spherical accelerator 2 Spherical motor 3 Rotor 5 Support plates 6A, 6B, 6C, 6D, 6E Rotation transmission sphere 7 Rotation suppression mechanism 8 Output sphere C Virtual transmission axis CP Parallel axis CV Rotation suppression mechanism center and rotation suppression mechanism Axis line connecting the contact point between the rotation suppression mechanism and the rotation transmission sphere C7 Rotation axis of the rotation suppression mechanism O3 Center of the rotor O8 Center of the output sphere OA, OB Center of the rotation transmission sphere P Orthogonal plane P6 Contact point between the rotation suppression mechanism and the rotation transmission sphere

Claims (6)

A spherical accelerator / reducer including a spherical motor and an output sphere, which transmits the rotation of the rotor of the spherical motor to the output sphere to rotate the output sphere.
It is a sphere provided in contact with each of the rotor and the output sphere, and includes a plurality of rotation transmission spheres that rotate with the rotation of the rotor and rotate the output sphere.
Each of the plurality of rotation transmission spheres is in an orthogonal plane that passes through the center of the rotation transmission sphere and is orthogonal to the virtual transmission axis when the axis connecting the centers of the rotor and the output sphere is used as the virtual transmission axis. Is rotatably provided around any axis
A spherical accelerator / reducer provided with a rotation suppression mechanism that suppresses rotation of each of the plurality of rotation transmission spheres around a parallel axis that passes through the center of the rotation transmission sphere and is parallel to the virtual transmission axis. The rotation suppressing mechanism is a rotating body provided so as to individually contact each of the plurality of rotation transmitting spheres.
The rotation axis of the rotating body extends in the orthogonal plane and is provided orthogonal to the axis line connecting the center of the rotation transmission sphere corresponding to the rotating body and the contact point between the rotation transmission spheres. The spherical accelerator / reducer according to claim 1. The spherical accelerator / reducer according to claim 2, wherein a plurality of the rotating bodies are provided with respect to one of the rotation transmitting spheres. The spherical accelerator / reducer according to claim 2 or 3, wherein the rotating body is either a disk, an annular body, or a roller. A control device for controlling the rotation direction and rotation speed of the rotor is further provided.
The control device is based on the acceleration / deceleration ratio of the rotation of the rotor and the output sphere about the arbitrary axis in the orthogonal plane and the acceleration / deceleration ratio of the rotation around the virtual transmission axis. The spherical accelerator / reducer according to any one of claims 1 to 4, wherein the output ball is rotated by adjusting the rotation direction and rotation speed of the rotor. A control method for a spherical accelerator / reducer, which comprises a spherical motor and an output sphere, and transmits the rotation of the rotor of the spherical motor to the output sphere to rotate the output sphere.
The spherical accelerator / reducer is a sphere provided in contact with each of the rotor and the output sphere, and includes a plurality of rotation transmission spheres that rotate with the rotation of the rotor and rotate the output sphere.
Each of the plurality of rotation transmission spheres is in an orthogonal plane that passes through the center of the rotation transmission sphere and is orthogonal to the virtual transmission axis when the axis connecting the centers of the rotor and the output sphere is used as the virtual transmission axis. Is rotatably provided around any axis
Each of the plurality of rotation transmission spheres is provided with a rotation suppression mechanism that suppresses rotation around a parallel axis parallel to the virtual transmission axis through the center of the rotation transmission sphere.
Rotation direction of the rotor based on the acceleration / deceleration ratio of the rotation of the rotor and the output sphere around the arbitrary axis in the orthogonal plane and the acceleration / deceleration ratio of the rotation around the virtual transmission axis. A method for controlling a spherical accelerator / reducer that rotates the output ball by adjusting the rotation speed.

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