Damping valve for shock absorber

1. A damping valve for a shock absorber, comprising:

a valve disk including a one-side disk and an other-side disk provided to be placed on the one-side disk and partitioning one chamber and another chamber;

a port configured to include through holes formed in the one-side and other-side disks and allowing communication between the one and the other chambers;

a shaft member penetrating through the valve disk; and

a nut for fixing the valve disk to the shaft member by being threadably mounted on the tip of the shaft member;

wherein:

an annular inner peripheral seat surface and an annular outer peripheral seat surface formed at an outer side of the inner peripheral seat surface are respectively formed at corresponding positions of each mating surface of the one-side and other-side disks;

the through holes are each open between each inner peripheral seat surface and each outer peripheral seat surface;

a plurality of the through holes, which are in the other-side disk, extending from the inner peripheral seat surface of the other-side disk to the outer peripheral seat surface of the other-side disk;

elastic deforming portions are formed between the plurality of through holes of the other-side disk; and

the elastic deforming portions of the other-side disk are strained and the inner peripheral seat surface of the one-side disk and that of the other-side disk come into contact in a state where the nut is tightened.

2. The damping valve for the shock absorber according to claim 1 , wherein:

the plurality of through holes in the other-side disk each have an identical arcuate shape, and are arranged at equal intervals.

3. The damping valve for the shock absorber according to claim 1 , wherein:

an annular groove communicating with each through hole is formed at least either between the outer peripheral seat surface and the inner peripheral seat surface of the one-side disk or between the outer peripheral seat surface and the inner peripheral seat surface of the other-side disk.

4. The damping valve for the shock absorber according to claim 1 , wherein:

a total opening area of the plurality of through holes in the other-side disk is set to be larger than that of another plurality of the through holes which are in the one-side disk.

5. The damping valve for the shock absorber according to claim 1 , further comprising:

a leaf valve arranged on the other-side disk with an inner peripheral side as a fixed end and configured to open and close the port.

6. The damping valve for the shock absorber according to claim 5 , wherein:

the leaf valve includes a plurality of leaf valves; and

the damping valve further comprises a ring mounted on any one of the plurality of leaf valves.

7. The damping valve for the shock absorber according to claim 1 , wherein:

the port is a one-side port for permitting the passage of working fluid from the one chamber to the other chamber and has a through hole of the through holes which is in the one-side disk and formed in an inner peripheral side of the one-side disk; and

the damping valve further comprises an other-side port for permitting the passage of the working fluid from the other chamber to the one chamber, and is formed in an outer peripheral side of the one-side disk.

8. A damping valve for a shock absorber, comprising:

a valve disk including a one-side disk and an other-side disk to be placed on the one-side disk, the valve disk partitioning one chamber and another chamber, the one-side disk having a mating surface mating with a mating surface of the other-side disk, each of the one-side disk and the other-side disk having an annular inner peripheral seat surface, and an annular outer peripheral seat surface, at an outer side of the inner peripheral seat surface, formed at corresponding positions of the respective mating surface;

a port including through holes formed in the one-side and other-side disks and allowing communication between the one and the other chambers, the through holes each being open between each of the inner peripheral seat surfaces and each of the outer peripheral seat surfaces, a plurality of the through holes, which are in the other-side disk, extending from the inner peripheral seat surface of the other-side disk to the outer peripheral seat surface of the other-side disk;

a shaft member penetrating through the valve disk; and

a nut for fixing the valve disk to the shaft member by being threadably mounted on a tip of the shaft member, the nut being movable between first and second positions,

wherein the other-side disk includes elastic deforming portions formed between the plurality of through holes of the other-side disk,

wherein with the nut in the first position, the outer peripheral seat surface of the one-side disk and the outer peripheral seat surface of the other-side disk are in direct contact, while a clearance is formed between the inner peripheral seat surface of the one-side disk and the inner peripheral seat surface of the other-side disk, and

wherein with the nut in the second position, the clearance is eliminated so that the inner peripheral seat surface of the one-side disk directly contacts the inner peripheral seat surface of the other-side disk.

9. The damping valve for the shock absorber according to claim 8 , wherein with the nut in the first position, the inner peripheral seat surface of the one-side disk and the inner peripheral seat surface of the other-side disk are free of direct contact.

10. A method for forming a damping valve for a shock absorber, comprising:

providing

a valve disk including a one-side disk and an other-side disk provided to be placed on the one-side disk, the one-side disk having a mating surface for mating with a mating surface of the other-side disk, each of the one-side disk and the other-side disk having an annular inner peripheral seat surface and an annular outer peripheral seat surface, which is at an outer side of the inner peripheral seat surface, formed at corresponding positions of the respective mating surface,

a port including through holes formed in the one-side and other-side disks, a plurality of the through holes, which are in the other-side disk, extending from the inner peripheral seat surface of the other-side disk to the outer peripheral seat surface of the other-side disk,

a shaft member penetrating through the valve disk, and

a nut for fixing the valve disk to the shaft member,

wherein the other-side disk includes elastic deforming portions formed between the plurality of through holes of the other-side disk;

threadably mounting the nut on a tip of the shaft member;

after the threadably mounting, tightening the nut to a first position, so that the outer peripheral seat surface of the one-side disk and the outer peripheral seat surface of the other-side disk are in direct contact, while a clearance is formed between the inner peripheral seat surface of the one-side disk and the inner peripheral seat surface of the other-side disk; and

after the tightening, further tightening the nut to a second position so that the clearance is eliminated such that the inner peripheral seat surface of the one-side disk directly contacts the inner peripheral seat surface of the other-side disk, wherein the valve disk partitions one chamber and another chamber, the port allows for communication between the one and the other chambers, and each of the through holes of the port are open between each of the inner peripheral seat surfaces and each of the outer peripheral seat surfaces.

11. The method of claim 10 , wherein with the nut in the first position, the inner peripheral seat surface of the one-side disk and the inner peripheral seat surface of the other-side disk are free of direct contact.