Tire testing device

1 . A test unit for tire testing, the test unit comprising:

an axle unit configured to rotatably support a test wheel on which a test tire is mounted in a state where the test wheel is in contact with a road surface; and

an alignment unit configured to adjust a load acting on the test wheel,

wherein the alignment unit includes a load adjustment mechanism configured to adjust the load acting on the test wheel,

wherein the load adjustment mechanism includes:

a first movable frame movable vertically;

linear guides configured to guide the vertical movement of the first movable frame; and

a first drive unit configured to drive the first movable frame vertically,

wherein the first movable frame has a substantially inverted U-shaped cross section when cut along a plane orthogonal to a rotation axis of the test wheel, and

wherein the linear guides are on outer sides of the substantially inverted U-shape of the first movable frame so that the first movable frame is sandwiched by the linear guides.

2 . The test unit according to claim 1 ,

further comprising a base frame,

wherein the linear guides each include:

a rail attached to one of the base frame and the first movable frame; and

a carriage attached to the other of the base frame and the first movable frame and configured to travel on the rail,

wherein the first drive unit includes:

a motion converter; and

a second motor configured to drive the motion converter,

wherein the motion converter includes:

a main body attached to the base frame; and

a movable part that is movable vertically with respect to the main body, and

wherein the first movable frame is fixed to the movable part.

3 . The test unit according to claim 1 ,

wherein the alignment unit further includes a camber angle adjustment mechanism configured to adjust a camber angle of the test wheel, and

wherein the camber angle adjustment mechanism includes:

a second movable frame that is rotatable about an E φ axis parallel to a traveling direction;

a first pivot projecting from the second movable frame coaxially with the E φ axis;

a third bearing configured to rotatably support the first pivot; and

a φ drive unit configured to rotationally drive the second movable frame.

4 . The test unit according to claim 3 ,

further comprising a curved guide configured to guide rotation of the second movable frame.

5 . The test unit according to claim 3 ,

wherein the alignment unit further includes a slip angle adjustment mechanism configured to adjust a slip angle of the test wheel, and

wherein the slip angle adjustment mechanism includes:

a third movable frame that is rotatable about an E φ axis orthogonal to each of an E λ axis, which is the rotation axis of the test wheel, and the E φ axis;

a second pivot projecting from the third movable frame coaxially with the E θ axis;

a fourth bearing configured to rotatably support the second pivot; and

a θ drive unit configured to rotationally drive the third movable frame.

6 . The test unit according to claim 1 ,

wherein the axle unit includes:

a spindle;

a fifth bearing configured to rotatably support the spindle; and

a wheel hub coaxially attached to a distal end of the spindle and to which the test wheel is to be attached.

7 . The test unit according to claim 6 ,

wherein the axle unit includes a braking device configured to brake rotation of the spindle.

8 . The test unit according to claim 7 , further comprising:

a power unit configured to output power for rotationally driving the test wheel; and

a power transmission unit configured to transmit power output from the power unit to the spindle,

wherein the power transmission unit includes a sliding constant velocity joint having one end coupled to the spindle.

9 . A test unit for tire testing, the test unit comprising:

an axle unit configured to rotatably support a test wheel on which a test tire is mounted in a state where the test wheel is in contact with a road surface; and

an alignment unit configured to adjust an orientation of the test wheel,

wherein the alignment unit includes a camber angle adjustment mechanism configured to adjust a camber angle of the test wheel,

wherein the camber angle adjustment mechanism includes:

a second movable frame that is rotatable about an E φ axis parallel to a traveling direction;

curved guides configured to guide rotation of the second movable frame;

a first pivot projecting from the second movable frame coaxially with the E φ axis;

a third bearing configured to rotatably support the first pivot; and

a φ drive unit configured to rotationally drive the second movable frame,

wherein the second movable frame has a substantially inverted U-shaped cross section when cut along a plane orthogonal to a rotation axis of the test wheel, and

wherein the curved guides are on outer sides of the substantially inverted U-shape of the second movable frame so that the second movable frame is sandwiched by the curved guides.

10 . The test unit according to claim 9 ,

wherein the alignment unit further includes a slip angle adjustment mechanism configured to adjust a slip angle of the test wheel, and

wherein the slip angle adjustment mechanism includes:

a third movable frame that is rotatable about an E θ axis orthogonal to each of an E λ axis, which is the rotation axis of the test wheel, and the E φ axis;

a second pivot projecting from the third movable frame coaxially with the E θ axis;

a fourth bearing configured to rotatably support the second pivot; and

a θ drive unit configured to rotationally drive the third movable frame.

11 . The test unit according to claim 9 ,

wherein the axle unit includes:

a spindle;

a fifth bearing configured to rotatably support the spindle; and

a wheel hub coaxially attached to a distal end of the spindle and to which the test wheel is to be attached.