Crawler-type traveling body and traveling apparatus

1 . A crawler-type traveling body comprising:

a crawler;

a drive wheel including a drive shaft, the drive wheel configured to apply a driving force to the crawler;

at least two track rollers disposed below the drive wheel, the crawler being stretched around the drive wheel and said at least two track rollers;

an auxiliary mechanism between said at least two track rollers, the auxiliary mechanism includes:

a swing shaft;

a first auxiliary wheel; and

a second auxiliary wheel, the first auxiliary wheel and the second auxiliary wheel being swingable around the swing shaft; and

a tensioner coupled to the drive shaft of the drive wheel, the tensioner configured to press the drive wheel against the crawler to apply tension to the crawler,

wherein a push-up amount of the first auxiliary wheel pushed up in a vertical direction is larger than a push-down amount of the second auxiliary wheel pushed down in the vertical direction in a swing movement of the auxiliary mechanism, and

the drive wheel includes an in-wheel motor that transmits a rotative force to the drive wheel.

2 . The crawler-type traveling body according to claim 1 , further comprising side plates configured to support the swing shaft,

wherein auxiliary mechanism includes a coupler coupling the first auxiliary wheel and the second auxiliary wheel, and

the swing shaft is coupled to the side plates and is configured to swingably support the coupler.

3 . The crawler-type traveling body according to claim 2 ,

wherein the first auxiliary wheel has a first axle shaft,

the second auxiliary wheel has a second axle shaft,

a first line segment joins the first axle shaft and the swing shaft,

a second line segment joins the second axle shaft and the swing shaft, and

an angle θ between the first line segment and the second line segment is in a range of 90°<0≤105°.

4 . The crawler-type traveling body according to claim 3 ,

wherein the coupler includes:

a swing portion having a double-sided structure configured to support the first auxiliary wheel and the second auxiliary wheel; and

a set collar configured to secure the swing portion to the swing shaft.

5 . The crawler-type traveling body according to claim 4 ,

wherein the coupler includes a bush member at a junction between the swing portion and the swing shaft.

6 . The crawler-type traveling body according to claim 4 , wherein each of the first auxiliary wheel and the second auxiliary wheel includes an oil seal inside the double-sided structure.

7 . The crawler-type traveling body according to claim 1 ,

wherein the first auxiliary wheel has a first axle shaft,

the second auxiliary wheel has a second axle shaft,

the first auxiliary wheel includes a first bearing at a center of the first axle shaft, and

the second auxiliary wheel includes a second bearing at a center of the second axle shaft.

8 . The crawler-type traveling body according to claim 7 ,

the first auxiliary wheel includes a first set collar at each side of the first bearing, and

the second auxiliary wheel includes a second set collar at each side of the second bearing.

9 . The crawler-type traveling body according to claim 1 ,

wherein a part of the crawler between said at least two track rollers is in contact with a road surface, and

a perpendicular line from the drive shaft of the drive wheel is perpendicular to a straight line connecting shafts of said at least two track rollers, and

the first auxiliary wheel is opposite to the second auxiliary wheel across the perpendicular line.

10 . The crawler-type traveling body according to claim 9 ,

wherein the first auxiliary wheel is symmetric to the second auxiliary wheel with respect to the perpendicular line.

11 . The crawler-type traveling body according to claim 1 ,

wherein the push-up amount of the first auxiliary wheel is a half of a distance between the first auxiliary wheel and the second auxiliary wheel, and

the push-down amount of the second auxiliary wheel is equal to or less than a quarter of the distance.

12 . The crawler-type traveling body according to claim 1 , further comprising side plates supporting the drive wheel and said at least two track rollers.

13 . A traveling apparatus comprising:

a plurality of crawler-type traveling bodies including the crawler-type traveling body according to claim 1 ; and

a main body coupling at least two of the plurality of crawler-type traveling bodies.

14 . The crawler-type traveling body according to claim 1 , wherein the auxiliary mechanism includes a link supporting the first auxiliary wheel and the second auxiliary wheel, and

the crawler-type traveling body further includes a position control motor to adjust heights of the first auxiliary wheel and the second auxiliary wheel by moving the link up and down to change a height of the link.