Carriage
A carriage moves along rail parts having straight portions and curved portions. The carriage has a pedestal section, and in the pedestal section, at least two first rotor parts and one or a pair of second rotor parts, which are located between the rail parts and which include a pair of wheels that rotate while in contact with side surfaces of the rail parts. The pair of wheels are attached to the pedestal section via support members. Support members of the first rotor parts are located in the pedestal section on predetermined reference lines that overlap center lines of the straight portions of the rail parts when the carriage is moving along the straight portions, and are rotatably connected to the pedestal section such that the rotational centers are positions off a line connecting the rotational centers of the pair of wheels.
1 . A carriage moving along a rail part having a straight section and a curved section, comprising:
a base unit;
at least two first rotor units each including a pair of first wheels rotatably provided on the base unit in such a way as to sandwich the rail part therebetween, each of the first wheels abutting and rolling on a side surface of the rail part; and
one or a pair of second rotor units each including a pair of second wheels rotatably provided on the base unit in such a way as to sandwich the rail part therebetween, each of the second wheels abutting and rolling on a side surface of the rail part;
wherein
the pair of second wheels in each of the second rotor units is attached to the base unit via a second support member, and
the pair of first wheels in each of the first rotor units is attached to the base unit via a first support member, the first support member being connected to the base unit in such a way as to be rotatable about a center of rotation located on a predetermined reference line of the base unit and offset from the line segment connecting the centers of rotation of the pair of first wheels, the predetermined reference line being a line that overlaps the center line of the straight section of the rail part when the carriage is moving along the straight section, wherein
the carriage includes the pair of second rotor units,
the second support members of the second rotor units are fixedly attached to the base unit, and
when the radius of the center line of the curved section of the rail part is R, the width of the rail part is W, the diameter of the second wheel is D, the largest distance between the predetermined reference line and the center line of the rail part along the radial direction of the curved section of the rail part while the carriage is moving along the curved section of the rail part is δ, the distance between the centers of rotation of the two second wheels that are adjacent to each other along the rail part and located on the inner side of the curved section of the rail part when the carriage is moving along the curved section of the rail part is L 1 , and the distance between the centers of rotation of the two second wheels that are adjacent to each other along the rail part and located on the outer side of the curved section of the rail part when the carriage is moving along the curved section of the rail part is L 2 , the four second wheels of the pair of second rotor units are disposed in such a way that the distance between the predetermined reference line and the line segment connecting the centers of rotation of the two second wheels adjacent to each other along the rail part on the inner side of the rail part when the carriage is moving along the curved section of the rail part and the distance between the predetermined reference line and the line segment connecting the centers of rotation of the two second wheels adjacent to each other along the rail part on the outer side of the rail part when the carriage is moving along the curved section of the rail part are both equal to (W+D)/2 and that L 1 and L 2 satisfy the following equations:
L
1
=
2
(
R
-
W
+
D
2
)
2
-
(
R
-
δ
-
W
+
D
2
)
2
L
2
=
2
(
R
+
W
+
D
2
)
2
-
(
R
-
δ
+
W
+
D
2
)
2
.
2 . A carriage moving along a rail part having a straight section and a curved section, comprising:
a base unit;
at least two first rotor units each including a pair of first wheels rotatably provided on the base unit in such a way as to sandwich the rail part therebetween, each of the first wheels abutting and rolling on a side surface of the rail part; and
one or a pair of second rotor units each including a pair of second wheels rotatably provided on the base unit in such a way as to sandwich the rail part therebetween, each of the second wheels abutting and rolling on a side surface of the rail part;
wherein
the pair of second wheels in each of the second rotor units is attached to the base unit via a second support member, and
the pair of first wheels in each of the first rotor units is attached to the base unit via a first support member, the first support member being connected to the base unit in such a way as to be rotatable about a center of rotation located on a predetermined reference line of the base unit and offset from the line segment connecting the centers of rotation of the pair of first wheels, the predetermined reference line being a line that overlaps the center line of the straight section of the rail part when the carriage is moving along the straight section, wherein
the carriage includes the pair of second rotor units,
the second support member in each of the pair of second rotor units is rotatably connected to the base unit at the middle point of the line segment connecting the centers of rotation of the pair of second wheels, and
the center of rotation of the second support member in each of the pair of second rotor units is disposed on the predetermined reference line.
3 . The carriage according to claim 1 , wherein
the carriage includes the pair of second rotor units, and
the pair of second rotor units are arranged in such a way as to be sandwiched between the at least two first rotor units along the rail part.
4 . The carriage according to claim 2 , wherein
the carriage includes the pair of second rotor units, and
the pair of second rotor units are arranged in such a way as to be sandwiched between the at least two first rotor units along the rail part.