JPS61221565A - Double freedom degree dc motor capable of positioning - Google Patents

Abstract

PURPOSE:To enable a power shaft rod to be positioned at an optional position, by generating electromagnetic action respectively between a rotary unit and a substrate, and between the rotary unit and the power shaft rod. CONSTITUTION:By electromagnetic action between a magnetic field forming unit 16 and a coil 18 which are provided respectively for a rotary unit 1 and a substrate 5, the rotary unit 1 is rotated to the substrate 5. By electromagnetic action between a coil 19 and a magnetic field forming unit 17 which are provided respectively for the rotary unit 1 and a power shaft rod 11, the power shaft rod 11 is rotated around a shaft to meet at right angles to a shaft rotating to the rotary unit 1. As the result, the power shaft rod 11 is rotated around two shafts meeting at right angles to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a two-degree-of-freedom DC motor that can be used for positioning, such as a hand joint of a robot arm.

[Prior Art] The present inventors previously proposed a three-dimensional motor having three degrees of freedom (Japanese Patent Application No. 59-80058).

The three-dimensional motor described above has windings that generate rotating magnetic fields around three mutually orthogonal axes, and rotates in any direction within a stator that can generate a composite rotating magnetic field in any direction. It is constructed by providing a rotor that is supported in a rotor manner. Although this three-dimensional motor does not have a fixed rotation axis and can be rotated around any rotation axis, the control system inevitably becomes complicated because it has many degrees of freedom.

Furthermore, applications of linear motors and planar motors that have been developed into two-degree-of-freedom rotary motors are also known (Japanese Patent Application Laid-open Nos. 182782-1982 and 1927-1982), but these are all pulse-pulsed motors. Since this is a motor application, when driving at high speed, the problem of motor rotation not following pulses (tax adjustment) cannot be avoided.

[Problems to be Solved by the Invention] The purpose of the present invention is to simplify the control system while sacrificing the degree of freedom compared to the three-dimensional motor. It is configured to be controllable using the same simple control method, and the second type of pulse motor application mentioned above.
It is an object of the present invention to provide a two-degree-of-freedom DC motor which eliminates the drawbacks of a degree-of-freedom rotary motor.

Another object of the present invention is to effectively utilize the configuration for giving the motor two degrees of freedom and provide a rotation measuring means for positioning the output shaft rod at an arbitrary position, thereby making it possible to control the robot arm. It is an object of the present invention to provide a positionable two-degree-of-freedom DC motor with a simple configuration suitable for use in hand joints, etc.

Means for Solving Problem E] In order to achieve the above object, the two-degree-of-freedom DC motor of the present invention has a rotating body rotatably supported by a stationary base, and an axis perpendicular to the axis of rotation. An output shaft rod is rotatably attached around the base body and the output shaft rod, and magnetic field forming bodies having different polarities arranged alternately in the relative rotational direction with respect to the rotating body are provided on the base body and the output shaft rod. A coil is provided that faces the forming body and generates a relative rotational force between the magnetic field forming body, and a commutator mechanism is provided between the base body and the rotating body and between the rotating body and the output shaft rod. It is constructed by providing a rotation measuring means for detecting mutual rotation angles and rotation angular velocities and feeding them back to the input side.

[Function] In the two-degree-of-freedom DC motor of the present invention having the above configuration, the rotating body rotates with respect to the base due to the electromagnetic action between the magnetic field forming body and the coil provided on each of the rotating body and the base, In addition, due to the electromagnetic action between the coils provided on the rotating body and the output shaft rod, and the magnetic field forming body, the output shaft rod rotates with respect to the rotating body around an axis perpendicular to the axis of rotation, thereby outputting The shaft rod will rotate around two orthogonal axes.

The rotation angle and rotational angular velocity of the rotating body and output shaft rod are detected by a rotation measuring means, and the detection signal is fed back to the control device on the input side, so that the output shaft rod can be accurately positioned at any position. can.

[Effects of the Invention] The two-degree-of-freedom DC motor of the present invention generates driving force by electromagnetic action similar to that in a general-purpose electric type l-degree-of-freedom DC motor, so it is easy to control a general l-axis DC motor. The method can be applied, the control system is therefore simplified, and since the joint mechanism and actuator are used together, the product as a whole can be made smaller and lighter.

In addition, since the rotation of the rotating body and output shaft rod is detected by the one-rotation measuring means and fed back to the control device, it is possible to position the output shaft rod at any position around the two axes, and also to drive the output shaft rod. can be performed at significantly higher speeds than those using conventional pulse motors.

[Embodiment] Fig. 1 shows an embodiment of the present invention, in which this two-degree-of-freedom DC motor has a cross-shaped arm rod 2.3 that protrudes in two mutually orthogonal X*s' axes directions. Equipped with a body l,
This rotary body 1 is rotatably supported around the X-axis by an arm rod 2 with respect to a base body 5 as a stationary system in a robot arm or the like.

That is, a bifurcated support arm 7 is attached to a fixed shaft rod 8 fixed to the base body 5.
, and the both end support portions 8.8 of the support arm 7 are rotatably inserted into both ends of the arm rod 2 along the X axis of the rotating body 1 via a commutator mechanism and rotation measuring means, respectively, which will be described later. are doing.

Furthermore, both end supports 10.10 of the output extraction support arm 8 are rotatable at both ends of the arm rod 3 along the y-axis of the rotating body l via a commutator mechanism and rotation measuring means similar to those described above. The supporting arm θ and the output shaft rod 11 fixed thereto are attached to the rotating body 1 so as to be rotatable around the y-axis.

Therefore, by rotating the rotating body 1 around the X-axis relative to the support arm 7 and rotating the support arm 8 around the y-axis relative to the rotating body 1, the output shaft rod 11 is It rotates around the axis with two degrees of freedom.

As the driving force for causing each of the above rotations, electromagnetic force based on the same principle as a DC motor is used.

In order to generate the electromagnetic force, each of the supporting arms 7.9 is provided with a magnetic field forming body 113.17, and the rotating body l is provided with a coil 18. lO is provided.

The magnetic field forming body 17 has a configuration as shown in FIG. In addition, in FIG. 2, the magnetic field forming body 1
Although only the structure of the magnetic field forming body 7 is shown, the other magnetic field forming body 18 is also substantially the same except for the direction. The magnetic field forming body 17 shown in the figure has a large number of permanent magnets 21 connected to an inwardly curved spherical or cylindrical surface arranged in the rotation direction of the opposing coil 19, and the magnets 2! The arrangement is such that adjacent magnets with the same polarity face each other, thereby generating a magnetic field in the direction of arrow A between each magnet.

Furthermore, as shown in FIG. 1, the coils 18.19 provided on the rotating body l protrude in the z-axis direction perpendicular to the X, ry, and y axes, and are arranged opposite to the magnetic field forming body 1111.17.
The coils 18.18 are arranged so that a current flows in a direction perpendicular to the direction of relative rotation with the magnetic field forming body 113.17 (in the direction of arrow B in FIG. 2), and these coils 18.
It is connected to a DC power source 33 (see FIG. 3), which will be described later, through a commutator mechanism 24, 25 provided at one end of the power source 3.

The commutator mechanism 25 includes a support arm 3 as shown in FIG.
The commutator 2 is mounted around the insulating column 28 fixed to the support lO of the
9 are arranged and fixed, and are rotatably inserted into the hollow part 32 of the arm rod 3 through the insulating sleeve 30 and the bearing 31, so that each adjacent commutator 28 alternately has a different polarity, and
The pair of commutators 28 at opposite positions are connected to the DC power supply 33 so that they have different polarities, and the pair of commutators 28 at opposite positions
Then, the brushes 34, 34 fixed to the arm rod 3 are brought into electrically conductive contact, and these brushes 34, 34 are electrically connected to the coil 19.

Thereby, the two brushes 34, 34 are connected to a pair of commutators 29 connected to mutually different electrodes in the DC power supply 33.
．． 29, and as the arm rod 3 rotates, the pair of brushes 34, 34 sequentially contact the commutator 29, 29 connected to the corresponding pole, and as a result, the current flowing through the coil 19 is Along with the above rotation, the rotation is sequentially reversed.

It goes without saying that the other commutator mechanism 24 is also configured in the same manner as described above.

Further, in order to position the output shaft rod 11 at an arbitrary position, as shown in FIG. l
Rotation measuring means 41 and 42 are provided between the arm rods 2 and 3 of the rotating body 1, respectively. Each of the above-mentioned rotation measuring means 41.
42 is an angle detector 43.44 such as a potentiometer that measures the rotation angle between the rotating body l and the support arm 7.9;
It is composed of angular velocity detectors 45, 48 such as tough generators for measuring the rotational angular velocity between the rotating body 1 and the support arm 7.9, and these detectors are connected to each of the coils 18.
The control device on the input side is connected to a control device (not shown) that controls the energization to the coils 18 and 19, and receives the rotation angle and rotational angular velocity of the rotating body 1 and the support arm 8 that are generated when the energization is applied to each coil 18 and 19. It is configured to provide feedback.

The configuration explained and illustrated above shows the basic configuration in principle, and therefore, in reality, it is possible to increase the number of turns of the coil, increase the number of poles, or use an iron core etc. to create a stronger magnetic field. It is natural that it is effective to create a

In the DC motor having the above configuration, the permanent magnet 2 of the magnetic field forming body 18
The electromagnetic force acting between the coil 18 and the coil 18 causes the rotating body 1 to rotate around the X axis relative to the base 5, and the electromagnetic force acting between the coil 18 and the permanent magnet 21 causes the support arm 9 And the output shaft rod 11 rotates around the y-axis with respect to the rotating body l.

These rotational forces are generated when a current in the direction of arrow B flows through the coil 19 arranged in the direction crossing the magnetic field in the direction of arrow A in FIG. A driving force is generated in the direction of arrow C, and this
8 acts as a rotational force. Further, when the coil 18 moves close to the adjacent magnetic field A with this rotation, the coil 13 has the above-mentioned commutator mechanism 25.
Due to the action of , a current flows in the opposite direction to that previously, and this causes an interaction between the permanent magnet and the coil in the same manner as described above, and the coil 19 continues to rotate in the direction of arrow C.

In this way, the rotating body 1 rotates around the X-axis, and the support arm 8 and the output shaft rod 11 rotate around the Y-axis, but the rotation direction, rotation angle, and angular velocity of these are determined by the rotation measuring means. It is measured by the angle detector and the angular velocity detector at 41 and 42 and fed back to the control device. Thereby, the control device controls the energization of the coils 18 and 19, and the output shaft rod 11 is positioned at an arbitrary position.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is an explanatory diagram of its rotation principle, and FIG. 3 is an enlarged perspective view of the commutator mechanism. ! ... Rotating body, 5... Base, 11... Output shaft rod, te, i7... Magnetic field forming body,
18.19φ・Coil. 41.42 Fist/Rotation Measuring Means. ill

Claims (1)

[Claims] 1. An output shaft rod is attached to a rotating body rotatably supported by a stationary base so as to be rotatable around an axis perpendicular to the axis of rotation, and the output shaft rod is attached to the base and the output shaft so that the rotation body is rotatably supported. Magnetic field forming bodies having different polarities arranged alternately in the rotating direction are provided, and a coil is provided on the rotating body to face each magnetic field forming body and generate a relative rotational force between the magnetic field forming bodies. A commutator mechanism is provided between the base body and the rotating body and between the rotating body and the output shaft rod, and a rotation measuring means is provided for detecting the mutual rotation angle and rotational angular velocity and feeding it back to the input side. A two-degree-of-freedom DC motor capable of positioning.