Three-dimensional rigid ball driving system

Patent metadata

Field	Value
Publication number	US-9751644-B2
Application number	US-201314414852-A
Country	US
Kind code	B2
Filing date	Jul 24, 2013
Priority date	Jul 25, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

Provided is a three-dimensional rigid ball driving system including: a support frame having a polyhedral shape; a rigid ball positioned at the center of an inner portion of the support frame; a plurality of ball bearings installed at corners of inner sides of the support frame, respectively, and contacting a surface of the rigid ball; and a plurality of electromagnets disposed around the ball bearings and generating magnetic fields to rotate the rigid ball; and a controller controlling the electromagnets to control a rotation direction and a rotation speed of the rigid ball.

First claim

The invention claimed is:

1. A three-dimensional rigid ball driving system comprising:
a support frame ( 10 ) having a polyhedral shape;
a rigid ball ( 20 ) positioned at the center of an inner portion of the support frame ( 10 );
a plurality of ball bearings ( 30 ) installed at corners of inner sides of the support frame ( 10 ), respectively, and contacting a surface of the rigid ball ( 20 );
a plurality of electromagnets ( 40 ) disposed around the ball bearings ( 30 ) and generating magnetic fields to rotate the rigid ball ( 20 ); and
a controller ( 50 ) controlling the electromagnets ( 40 ) to control a rotation direction and a rotation speed of the rigid ball ( 20 ),
wherein the ball bearings ( 30 ) include balls ( 31 ), bearing racers ( 32 ) installed in the support frame ( 10 ) and having grooves ( 32 A) having the balls ( 31 ) seated therein and having a hemispherical shape, and bearing cages ( 33 ) coupled to upper portions of the bearing racers ( 32 ) and having guide grooves ( 33 A) formed therein and having a hemispherical shape,
the balls ( 31 ) being installed so as to be confined in grooves formed by allowing the grooves ( 32 A) of the bearing racers ( 32 ) and the guide grooves ( 33 A) of the bearing cages ( 33 ) to meet each other.

2. The three-dimensional rigid ball driving system of claim 1 , wherein centers of the balls ( 31 ) are positioned at points defined by following Equation 3:

X
=

±

R
+
r

(
3
)

,

Y
=

±

R
+
r

(
3
)

,

Z
=

±

R
+
r

(
3
)

[

Equation
⁢

⁢
3

]

where X, Y, and Z are coordinate values of points at which the centers of the balls ( 31 ) of the ball bearings ( 30 ) are positioned, R is a radius of the rigid ball ( 20 ), and r is a radius of the ball ( 31 ) of the ball bearing ( 30 ).

3. The three-dimensional rigid ball driving system of claim 1 , wherein the ball bearing ( 30 ) and the support frame ( 10 ) have a vibration damping member installed therebetween.

4. The three-dimensional rigid ball driving system of claim 1 , wherein a cross section of the support frame in a length direction has a ‘ ’ shape.

5. A three-dimensional rigid ball driving system comprising:
a support frame ( 10 ) having a polyhedral shape;
a rigid ball ( 20 ) positioned at the center of an inner portion of the support frame ( 10 );
a plurality of ball bearings ( 30 ) installed at corners of inner sides of the support frame ( 10 ), respectively, and contacting a surface of the rigid ball ( 20 );
a plurality of electromagnets ( 40 ) disposed around the ball bearings ( 30 ) and generating magnetic fields to rotate the rigid ball ( 20 ); and
a controller ( 50 ) controlling the electromagnets ( 40 ) to control a rotation direction and a rotation speed of the rigid ball ( 20 ),
wherein a cross section of the support frame in a length direction has a ‘ ’ shape.

Assignees

• Korea Aerospace Res Inst

Inventors

• Kim Dae-Kwan
• Yoon Hyungjoo
• Kang Wooyong
• Kim Yong Bok
• Choi Hong-Taek

Classifications

• B64G1/283

  using reaction wheels · CPC title

• H02K5/1737

  radially supporting the rotor around a fixed spindle; radially supporting the rotor directly · CPC title

• H02K41/025

  Asynchronous motors · CPC title

• H02K7/088

  radially supporting the rotor directly · CPC title

• H02K2201/18

  Machines moving with multiple degrees of freedom · CPC title