Hydraulic device, hydraulic motor and construction machine

1. A hydraulic device comprising:

a first block having a block inner circumferential portion and a plurality of internal teeth on the block inner circumferential portion;

a second block configured to rotate relative to the first block;

an oscillatory rotating body having a plurality of external teeth, the external teeth being smaller in number than the internal teeth, the oscillatory rotating body being provided inside the first block such that the oscillatory rotating body is oscillatorily rotatable, the oscillatory rotating body having an inner circumferential portion, the internal teeth and the external teeth defining a working chamber therebetween;

a rotation restricting shaft extending from the inner circumferential portion of the oscillatory rotating body in a direction intersecting a radial direction, the rotation restricting shaft coupling the oscillatory rotating body and the second block such that the oscillatory rotating body and the second block are not allowed to rotate relative to each other while allowing the oscillatory rotating body to oscillatorily rotate;

a first friction plate configured to rotate together with the oscillatory rotating body;

a second friction plate restricted from rotating by the second or first block; and

a press mechanism configured to press the first and second friction plates against each other.

2. The hydraulic device of claim 1 , wherein the first and second friction plates are shaped annularly, and

wherein the first and second friction plates are disposed in a region surrounding the rotation restricting shaft.

3. The hydraulic device of claim 1 , further comprises

a rotation converting block configured to extract only a rotation component from oscillatory rotation of the oscillatory rotating body as a rotation about an axis of rotation of the first block, and configured to rotate synchronously with the rotation; and

a bearing,

wherein the first friction plate is supported by the rotation converting block such that the first friction plate is not allowed to rotate relative to the rotation converting block, and

while being allowed to oscillatorily rotate, the oscillatory rotating body is supported by the first block via the rotation converting block and the bearing.

4. The hydraulic device of claim 1 , wherein the oscillatory rotating body has an end surface, and

wherein the first friction plate is attached to the end surface such that the first friction plate is not allowed to rotate relative to the oscillatory rotating body.

5. The hydraulic device of claim 1 , wherein the first friction plate is attached to an outer periphery of the rotation restricting shaft such that the first friction plate is not allowed to rotate relative to the rotation restricting shaft.

6. The hydraulic device of claim 1 , wherein the press mechanism includes:

a press member configured to apply a pressing force to the first and second friction plates;

a bias device configured to bias the press member in such a direction that the first and second friction plates frictionally touch each other; and

a brake release device configured to move the press member in such a direction that frictional contact between the first and second friction plates is removed.

7. The hydraulic device of claim 6 , wherein the brake release device is constituted by a piston device configured to move the press member in a friction removing direction using pressure produced by an introduced hydraulic fluid.

8. The hydraulic device of claim 7 , wherein, as well as the first and second friction plates, the press member, the bias device and the piston device are disposed in a region surrounding the rotation restricting shaft.

9. A construction machine comprising:

a traveling drive unit; and

a hydraulic motor configured to drive the traveling drive unit using a pressure produced by a hydraulic fluid,

wherein the hydraulic motor is the hydraulic motor of claim 1 .

10. The hydraulic device of claim 1 , wherein the rotation restricting shaft is disposed while meshing with a spline hole in a spline block, which is disposed in a middle portion of the second block in the direction intersecting the radial direction, and meshing with a spline hole in the oscillatory rotating body, and

wherein the spline block is seamlessly coupled with the second block.

11. The hydraulic device of claim 1 , further comprises

a brake mechanism configured to lock oscillatory rotation of the oscillatory rotating body,

wherein a central axis of the second block coincides with an axis of rotation of the first block,

an axial direction parallel to the central axis and the axis of rotation includes:

a first direction from the first block toward the second block; and

a second direction from the second block toward the first block,

wherein at least part of the brake mechanism is disposed in a region surrounding the rotation restricting shaft,

wherein the brake mechanism includes:

the first friction plate;

the second friction plate; and

the press mechanism,

wherein the press mechanism includes:

a press member configured to apply a pressing force to the first and second friction plates;

a bias device configured to bias the press member in such the second direction that the first and second friction plates frictionally touch each other; and

a brake release device configured to move the press member in such the first direction that frictional contact between the first and second friction plates is removed.