KR20080092597A

KR20080092597A - Auxillary wheel unit

Info

Publication number: KR20080092597A
Application number: KR1020070036107A
Authority: KR
Inventors: 이상규
Original assignee: (주)한국로보틱스
Priority date: 2007-04-12
Filing date: 2007-04-12
Publication date: 2008-10-16

Abstract

The present invention provides an auxiliary wheel unit used in a wheel assembly for moving the robot body forward, comprising: a first casing fixed to the robot body so that relative rotation is impossible with respect to the robot body; A first auxiliary wheel that is coupled to allow relative rotation with respect to the first casing and rotates when the robot body moves; A second casing fixed to a lower front of the robot body such that relative rotation is impossible with respect to the robot body; And a second auxiliary wheel which is coupled to allow relative rotation with respect to the second casing and rotates when the robot body moves. The first auxiliary wheel has the same plane as the rotational center axis of the first casing. It is to provide an auxiliary wheel unit, characterized in that coupled to the first casing rotatably around a virtual straight line in the same direction as the moving direction of the robot body.

Description

Auxillary wheel unit

1 is a view for explaining an example of a conventional auxiliary wheel unit.

2 is a view for explaining the radius of rotation of the casing of the auxiliary wheel unit shown in FIG.

Figure 3 is a perspective view of the auxiliary wheel unit according to an embodiment of the present invention.

4 is an exploded perspective view of the first auxiliary wheel shown in FIG. 3;

5 is a cross-sectional view of the first auxiliary wheel shown in FIG.

6 is an exploded perspective view of the second auxiliary wheel shown in FIG. 3.

7 and 8 are views for explaining the operation of the first auxiliary wheel shown in FIG.

** Explanation of symbols for the main parts of the drawing **

10: first casing 20: first auxiliary wheel

21: first shaft 22: first auxiliary wheel body

23: first satellite wheel 24: first wheel cover

25: first rubber wheel 30: second casing

40: second auxiliary wheel 41: second shaft

42: second auxiliary wheel body 43: second satellite wheel

44: second wheel cover 45: second rubber wheel

The present invention relates to an auxiliary wheel unit for use in a wheel assembly for a robot, and more particularly, by coupling to a casing fixed to prevent relative rotation with respect to the robot body, thereby reducing the area of the bottom of the robot body and thus designing an efficient robot. A secondary wheel unit has been improved in structure to make it possible.

There are various kinds of robots moving indoors according to their purpose, such as cleaning robot and guide robot. These robots are all used for the wheel assembly for the robot for movement.

Such a wheel assembly for the robot is installed on the lower surface of the robot body, and generally consists of a pair of drive wheels and auxiliary wheel units installed on both sides of the robot body, the auxiliary wheel unit is installed on the front and rear of the robot body respectively. And a pair of auxiliary wheels. These auxiliary wheels are usually manufactured in one piece made of plastic or rubber.

The auxiliary wheel is rotatably coupled to a casing that is coupled to the lower surface of the robot body. When the casing is coupled to the robot body in a rotatable manner, the auxiliary wheel does not rotate when the robot rotates in place to change directions. Since the robot body rotates in a non-active state, the robot does not rotate smoothly by friction with the floor, or the casing is deformed by the force transmitted to the auxiliary wheel from the ground, or the casing and auxiliary wheel are released. There is a problem.

Due to this problem, as shown in FIG. 1, the casing 3 is rotatably coupled to the robot body 1, and the auxiliary wheel 4 is rotatably coupled to the casing 3. . In Fig. 1, the part indicated by reference numeral 2 is a driving wheel.

On the other hand, in this auxiliary wheel unit, in order to facilitate the rotation of the casing (3), the center of rotation of the casing (3) and the center of rotation of the auxiliary wheel (4) is configured to be different from each other.

In this case, the casing 3 should rotate, and the rotation center R of the casing 3 is different from that of the casing 3 and the center of rotation of the auxiliary wheel 4, as shown in FIG. This is very large, and this causes a problem that the area of the lower surface of the robot body 1 must be secured to a certain degree.

In addition, when the pressing means (not shown) such as a spring is mounted on the driving wheel 2 to increase the traction force of the driving wheel 2, as shown in FIG. Although not shown in front of the center of rotation and not shown, when the auxiliary wheel (4) is located behind the casing (3) because the support point of the robot body 1 is different, the movement of the robot is not smooth There was also a problem.

The present invention has been made to solve the above-described problems, and while the casing to which the auxiliary wheel is coupled is relatively impossible to rotate relative to the robot body, it provides an auxiliary wheel unit that can be rotated very smoothly. There is a purpose.

In order to achieve the above object, the present invention,

In the auxiliary wheel unit used in the wheel assembly for moving the robot body forward,

A first casing fixed to a lower front of the robot body such that relative rotation is impossible with respect to the robot body;

A first auxiliary wheel that is coupled to allow relative rotation with respect to the first casing and rotates when the robot body moves;

A second casing fixed to a lower front of the robot body such that relative rotation is impossible with respect to the robot body; And,

And a second auxiliary wheel that is coupled to allow relative rotation with respect to the second casing and rotates when the robot body moves.

The first auxiliary wheel is on the same plane as the axis of rotation relative to the first casing, characterized in that coupled to the first casing rotatably around an imaginary straight line in the same direction as the moving direction of the robot body. Provide the auxiliary wheel unit.

The first auxiliary wheel,

First shafts having both ends fixed to the frame;

A pair of first auxiliary wheel bodies having an inner side coupled to the first shaft so as to be relatively rotatable with respect to the first shaft, and having an outer side of the first main body groove at a predetermined interval along the circumferential direction thereof;

A circular ring and an annular wheel having the same number as the number of the first body grooves so as to be fitted into the ring and to each of the first body grooves, wherein each of the annular wheels is formed of the first auxiliary wheel body. A pair of first satellite wheels fitted into and coupled to the first body groove from the outside;

A first cover groove having the same number as the number of the annular wheels is formed along the circumferential direction so that each of the annular wheels can be fitted, and the first auxiliary wheel body and the first satellite are located outside the first satellite wheel. A pair of first wheel covers coupled with the wheels; And

A first rotation wheel coupled to the pair of the first auxiliary wheel body relative to the pair of the first auxiliary wheel body to enable relative rotation, the outer diameter of the first satellite wheel larger than the outer diameter,

The first rubber wheel contacts the floor when the robot body is in normal driving, and when the robot body rotates, the first auxiliary wheel body is centered on a virtual straight line in the same direction as the moving direction of the robot body with respect to the shaft. It is preferable that the first satellite wheel is in contact with the floor while being rotated at an angle.

The first shaft includes a spherical first shaft body and rod-shaped first shaft wings extending in both directions from the first shaft body,

Each of the first auxiliary wheel body extends in the direction of the shaft wing from the spherical surface corresponding to the first shaft body and the spherical body, and the length of the vertical direction increases toward the outside so that the shaft wing can move in the vertical direction. It is preferable that a pair of taper parts are provided.

The second auxiliary wheel is coupled to the second casing to be rotatable about an imaginary straight line in the same plane as the axis of rotation of the second casing and in the same direction as the moving direction of the robot body.

A second shaft having both ends fixed to the frame;

A pair of second auxiliary wheel bodies having an inner side coupled to the second shaft so as to be relatively rotatable with respect to the second shaft, and an outer side of the second main body groove having a predetermined interval along the circumferential direction thereof;

A circular ring and an annular wheel having the same number as the number of the second main body grooves so as to be fitted into the ring and to each of the second main body grooves, each of the annular wheels of the second auxiliary wheel body; A pair of second satellite wheels fitted into and coupled to the second body groove from the outside;

A second cover groove having the same number as the number of the annular wheels is formed along the circumferential direction so that each of the annular wheels can be fitted, and the second auxiliary wheel main body and the second satellite are located outside the second satellite wheel. A pair of second wheel covers coupled with the wheels; And

Coupled to the pair of the second auxiliary wheel body between the pair of the second auxiliary wheel body so as to allow relative rotation, including a second rubber wheel of an outer diameter larger than the outer diameter of the second satellite wheel,

The second rubber wheel is in contact with the floor when the robot body is in normal running, and when the robot body is rotated, the second auxiliary wheel body is centered on a virtual straight line in the same direction as the moving direction of the robot body with respect to the shaft. Preferably, the second satellite wheel is in contact with the floor while being rotated at an angle.

The second shaft includes a spherical second shaft body and a rod-shaped second shaft blade extending in both directions from the second shaft body,

Each of the second auxiliary wheel body extends in the direction of the shaft wing from the spherical surface and the spherical surface corresponding to the second shaft body, and the length of the vertical direction increases toward the outside so that the shaft wing can move in the vertical direction. It is preferable that a pair of taper parts are provided.

Hereinafter, with reference to the drawings will be described a preferred embodiment of the present invention.

Figure 3 is a perspective view of the auxiliary wheel unit according to an embodiment of the present invention, Figure 4 is an exploded perspective view of the first auxiliary wheel shown in Figure 3, Figure 5 is a cross-sectional view of the first auxiliary wheel shown in Figure 4, 6 is an exploded perspective view of the second auxiliary wheel shown in FIG. 3, and FIGS. 7 and 8 are views for explaining the operation of the first auxiliary wheel shown in FIG. 3.

The auxiliary wheel unit according to the present embodiment is an auxiliary wheel unit used in the wheel assembly for moving the robot body 1, the first casing 10, the first auxiliary wheel 20, the second casing 30, The second auxiliary wheel 40 is formed.

The first casing 10 is fixed to the lower front of the robot body 1 so that relative rotation is impossible with respect to the robot body 1.

The first auxiliary wheel 20 is coupled to allow relative rotation with respect to the first casing 10 in the same direction as the rotation direction of the drive wheel 2 of the wheel assembly when the robot body 1 moves. Rotate The first auxiliary wheel 10 is on the same plane as the rotational center axis (C1 shown in FIG. 4) with respect to the first casing 10 and is a virtual straight line in the same direction as the moving direction of the robot body (see FIG. 4). It is coupled to the first casing 10 to be rotatable about the indicated C2).

As shown in FIGS. 4 and 5, the first auxiliary wheel 20 includes a first shaft 21, a first auxiliary wheel body 22, a first satellite wheel 23, and a first wheel cover 24. The first rubber wheel 25 is included.

The first auxiliary wheel 20 is on the same plane as the rotational center axis C1 of the first auxiliary wheel 20 and centers on a virtual straight line C2 in the same direction as the moving direction of the robot body 1. It is coupled to the first casing 10 so as to be rotatable.

Both ends of the first shaft 21 are fixed to the first casing 10 to become the center of rotation of the first auxiliary wheel 20.

As illustrated in FIG. 5, the first shaft 21 is a rod-shaped first shaft blade 212 extending in both directions from a spherical first shaft body 211 and the first shaft body 211. Is done.

The first auxiliary wheel body 22 is coupled to the first shaft 21 so as to be relatively rotatable with respect to the first shaft 22, and a pair is coupled to each of the first shaft blades 212. .

The first auxiliary wheel body 22 has a shape similar to that of a disc, and the first body groove 221 is provided at a predetermined interval along its circumferential direction.

The first taper extending in the direction of the first shaft blade 212 from the spherical surface 222 corresponding to the first shaft body 211 and the spherical surface 222 on the inner side of the first auxiliary wheel body 22. The unit 223 is provided.

The first taper portion 223 is configured to increase in length in the vertical direction toward the outside. In the present embodiment, the first taper portion 223 is configured to increase in inner diameter toward the outside. The shaft blade 212 may move in the vertical direction. By this configuration, the first auxiliary wheel 20 is in the same plane as the rotational center axis C1 with respect to the first casing 10, and a virtual straight line in the same direction as the traveling direction of the robot body 1. It is to be coupled to the first casing 10 to be rotated about (C2). On the other hand, the rotation is limited to the vertical straight line passing through the center of the first auxiliary wheel 20, the rotation is limited by the first casing 10 in the present embodiment, the first taper The shape of the part 223 is formed long in the vertical direction, and is formed in the form of a long hole in which the length of the vertical direction becomes longer toward the outside of the first taper part 223, so that the first shaft blade 212 is the first taper. It may be configured to be movable only in the vertical direction in the unit 223.

The first shaft blade 212 can move to some extent in the vertical direction within the first taper portion 223, so that the entire first auxiliary wheel 20 is constant around a virtual straight line denoted by C2. It will be able to rotate the angle.

The first satellite wheel 23 is provided in the same number as the number of the body grooves 22 to be fitted to the circular ring 231 and the ring 231 and to each of the body grooves 22. Wheel 232.

The first satellite wheel 23 is also provided with a pair, similar to the first auxiliary wheel body 22, the pair of the outer side of the first auxiliary wheel body 22 which is coupled to both sides of the first shaft 21. Each to.

The first wheel cover 24 is provided with a pair, and the pair of the first wheel cover 24 is accommodated in the first auxiliary wheel body 22 in a state in which the first satellite wheels 23 are received from the outside of the first satellite wheel 23. To combine.

The first wheel cover 24 is provided with a cover groove 241 equal to the number of the annular wheels 232.

Due to this structure, as shown in the cross-sectional view of FIG. 5, each annular wheel 232 has a first body groove 221 provided in the first subsidiary wheel body 22 and a cover groove provided in the first wheel cover 24. It becomes the state accommodated in 241.

The first rubber wheel 25 is coupled to the outer circumferential surface of the pair of first auxiliary wheel bodies 22 to allow relative rotation with respect to the first auxiliary wheel bodies 22. However, the first rubber wheel 25 and the first subsidiary wheel body 22 are not completely coupled so as to be relatively free of rotation, and may be configured to be relative to each other only when a predetermined or more frictional force is applied.

When the robot body 1 runs normally, as shown in FIG. 7, the entire first auxiliary wheel 20 rotates while the first rubber wheel 25 is in contact with the floor. At this time, the first rubber wheel 25 and the first auxiliary wheel body 22 rotates together.

When the robot main body 1 rotates in place, the pair of driving wheels 2 rotate in different directions, in which case the eccentric to the first auxiliary wheel 20 is caused by the rotation of the robot main body 1. As a result, as shown in FIG. 8, the annular wheel 232 of the first satellite wheel 23 is rotated at a predetermined angle with respect to the first shaft 21 as shown in FIG. 8. The first auxiliary wheel 20 is rotated in contact with the floor, and the first rubber wheel 25 and the first auxiliary wheel body 22 rotate relative to each other. That is, the first subsidiary wheel body 22 is fixed to the annular wheels 232, but the first rubber wheel 25 is not to rotate.

As shown in FIG. 3, the second casing 30 is fixed to the lower front of the robot body 1 such that relative rotation is impossible with respect to the robot body.

The second auxiliary wheel 40 is coupled to the second casing 30 so as to be relatively rotatable and rotates in a direction in which the driving wheel 2 rotates when the robot body 1 moves.

6 is an exploded perspective view of the second auxiliary wheel 40. In this embodiment, since the configuration of the second auxiliary wheel 40 is the same as the configuration of the first auxiliary wheel 20, the description of the structure of the second auxiliary wheel 40 is shown in FIG. 6 and the first auxiliary wheel 20. It will be made with reference to Fig. 5 which is a cross-sectional view of the, and the description of the operation will be made with reference to Figs. In the following description of the second auxiliary wheel 40, when referring to Figs. 5, 7 and 8, considering the reference numerals, the first auxiliary wheel corresponding to the components of the second auxiliary wheel 40 It is necessary to recognize by reference numerals of the components of the wheel 20. For example, referring to FIG. 5 while describing the second shaft 41, FIG. 5 refers to 21, which is the reference number of the first shaft, instead of 41, which is the reference number of the second shaft.

As shown in FIGS. 5 and 6, the second auxiliary wheel 40 includes a second shaft 41, a second auxiliary wheel body 42, a second satellite wheel 43, and a second wheel cover 44, the second rubber wheel 45 is included.

The second auxiliary wheel 40 is on the same plane as the rotational center axis C1 of the second auxiliary wheel 40 and centers on a virtual straight line C2 in the same direction as the moving direction of the robot body 1. It is coupled to the second casing 10 so that it can rotate.

Both ends of the second shaft 41 are fixed to the second casing 10 to become the center of rotation of the second auxiliary wheel 40.

As shown in FIG. 6, the second shaft 41 has a rod-shaped second shaft blade 412 extending in both directions from the spherical second shaft body 411 and the second shaft body 411. Is done.

The second auxiliary wheel body 42 is coupled to the second shaft 41 so as to be relatively rotatable with respect to the second shaft 42, and a pair is coupled to each of the second shaft blades 412. .

The second subsidiary wheel body 42 has a shape similar to that of a disc, and a second main body groove 421 is provided on the outside thereof at regular intervals along its circumferential direction.

A second taper extending in the direction of the second shaft blade 412 from the spherical surface 422 corresponding to the second shaft body 411 and the spherical surface 422 on the inner side of the second auxiliary wheel body 42. A part 423 is provided.

The second taper portion 423 is configured to increase in length in the vertical direction toward the outside. In the present embodiment, the second taper portion 423 is configured to increase in inner diameter toward the outside. The shaft blade 412 may move in the vertical direction. By this configuration, the second auxiliary wheel 40 is in the same plane as the rotational center axis C1 with respect to the second casing 10, and is a virtual straight line in the same direction as the traveling direction of the robot body 1. It is to be coupled to the second casing 10 to be rotated about (C2). On the other hand, the rotation is preferably limited to the vertical straight line passing through the center of the second auxiliary wheel 40, the rotation is limited by the second casing 10 in the present embodiment, the second taper The shape of the part 423 is elongated in the up and down direction, and is formed in the form of a long hole in which the length of the up and down direction becomes longer toward the outside of the second taper part 423, so that the second shaft blade 412 is the second taper. It may be configured to be movable only in the vertical direction in the unit 423.

The second shaft blade 412 may move to some extent in the vertical direction in the second tapered portion 423, whereby the second auxiliary wheel 40 as a whole is constant around an imaginary straight line denoted by C2. It will be able to rotate the angle.

The second satellite wheel 43 has an annular shape that is equal to the number of the body grooves 42 so that the second satellite wheels 43 fit into the circular ring 431 and the ring 431 and fit into the body grooves 42, respectively. Wheel 432.

The second satellite wheel 43 is also provided with a pair similar to the second auxiliary wheel body 42, the pair of the outer side of the second auxiliary wheel body 42 which is coupled to both sides of the second shaft (41). Each to.

The second wheel cover 44 is provided with a pair, and the pair is provided on the second auxiliary wheel body 42 in a state in which the second satellite wheels 43 are accommodated from the outside of the second satellite wheel 43. To combine.

The second wheel cover 44 is provided with a cover groove 441 equal to the number of the annular wheels 432.

Due to this structure, as shown in the cross-sectional view of FIG. 5, each annular wheel 432 has a second body groove 421 provided in the second auxiliary wheel body 42 and a cover groove provided in the second wheel cover 44. It is in a state accommodated in 441.

The second rubber wheel 45 is coupled to the outer circumferential surface of the pair of second auxiliary wheel body 42 to allow relative rotation with respect to the second auxiliary wheel body 42. However, the second rubber wheel 45 and the second subsidiary wheel body 42 are not completely coupled to be free to rotate relatively, and may be configured to be relative to each other only when a predetermined or more frictional force is applied.

When the robot body 1 runs normally, as shown in FIG. 7, the entire second auxiliary wheel 40 rotates while the second rubber wheel 45 contacts the floor. In this case, the second rubber wheel 45 and the second auxiliary wheel body 42 rotate together.

When the robot body 1 rotates in place, a pair of driving wheels 4 rotate in different directions, and in this case, the second auxiliary wheel 40 is eccentric by the rotation of the robot body 1. As a result, as shown in FIG. 8, the annular wheel 432 of the second satellite wheel 43 is rotated at a predetermined angle with respect to the second shaft 41 as shown in FIG. 8. The second auxiliary wheel 40 is rotated in contact with the floor, and at this time, the second rubber wheel 45 and the second auxiliary wheel body 42 rotate relative to each other. That is, the second subsidiary wheel body 42 to which the annular wheels 432 are fixed rotates, but the second rubber wheel 45 does not rotate.

As such, when the first auxiliary wheel 20 and the second auxiliary wheel 40 take the configuration of the rubber wheels 25 and 45 and the satellite wheels 23 and 43, the first casing 10 and the second casing 20 are used. ) Is constructed so that relative rotation is impossible with respect to the robot body, and the robot body 1 rotates in place for the change of direction while taking a configuration that does not increase the size of the robot body 1 more than necessary. , 43 are rotated to reduce the friction between the auxiliary wheels (20, 40) and the bottom surface has the advantage that can be smoothly rotate the robot body (1).

In the present embodiment, the case in which the configuration of the first auxiliary wheel and the second auxiliary wheel are the same, but the second auxiliary wheel is generally used to achieve the desired effect even when the configuration of the integrated rubber or the like. It is possible to achieve a better effect when the second auxiliary wheel takes the same configuration as the first auxiliary wheel. Therefore, even when the configuration of the second auxiliary wheel is different from the first auxiliary wheel should be considered to be included in the technical spirit of the present invention.

Although a preferred embodiment of the present invention has been described above, the technical idea of the present invention is not limited to the described embodiment, and the implementation of the auxiliary wheel unit of various forms is not limited to the technical idea of the present invention. It is obvious to those skilled in the art.

As described above, according to the present invention, while the casing to which the auxiliary wheel is coupled is coupled relative to the robot body impossible to rotate, while providing a secondary wheel unit that can be rotated very smoothly, the lower surface of the robot body No need to grow more than necessary, it is possible to provide an auxiliary wheel unit for the wheel assembly of the efficient robot.

Claims

The first auxiliary wheel is on the same plane as the axis of rotation relative to the first casing, characterized in that coupled to the first casing rotatably around an imaginary straight line in the same direction as the moving direction of the robot body. Auxiliary wheel unit.

The method of claim 1,

The first auxiliary wheel,

First shafts having both ends fixed to the frame;

A pair of first auxiliary wheel bodies having an inner side coupled to the first shaft so as to be relatively rotatable with respect to the first shaft, and having an outer side of the first main body groove at a predetermined interval along its circumferential direction;

The first rubber wheel contacts the floor when the robot body is in normal driving, and when the robot body rotates, the first auxiliary wheel body is centered on a virtual straight line in the same direction as the moving direction of the robot body with respect to the shaft. The auxiliary wheel unit, characterized in that the first satellite wheel in contact with the floor in a state rotated by a predetermined angle.

The method of claim 2,

Each of the first auxiliary wheel body extends in the direction of the shaft wing from the spherical surface corresponding to the first shaft body and the spherical body, and the length of the vertical direction increases toward the outside so that the shaft wing can move in the vertical direction. A secondary wheel unit, characterized in that the pair of tapered portion is provided.

The method of claim 2,

A second shaft having both ends fixed to the frame;

Including a second rubber wheel having an outer diameter larger than the outer diameter of the second satellite wheel, coupled to the pair of the second auxiliary wheel body relative to the pair of the second auxiliary wheel body, the outer diameter of the second satellite wheel,

The second rubber wheel is in contact with the floor when the robot body is in normal running, and when the robot body is rotated, the second auxiliary wheel body is centered on a virtual straight line in the same direction as the moving direction of the robot body with respect to the shaft. The auxiliary wheel unit, characterized in that the second satellite wheel in contact with the floor in a state rotated by a predetermined angle.

The method of claim 4, wherein

Each of the second auxiliary wheel body extends in the direction of the shaft wing from the spherical surface and the spherical surface corresponding to the second shaft body, and the length of the vertical direction increases toward the outside so that the shaft wing can move in the vertical direction. A secondary wheel unit, characterized in that the pair of tapered portion is provided.