Semi-pneumatic tire and semi-pneumatic tire manufacturing method

1. A semi-pneumatic tire, comprising:

a tread portion configured to make contact with a road surface;

a non-pneumatic portion coupled to an inner circumferential surface of the tread portion;

a pneumatic portion coupled to an inner circumferential surface of the non-pneumatic portion, the pneumatic portion including a space into which an air is filled; and

bonding layers respectively interposed between the tread portion and the non-pneumatic portion and between the non-pneumatic portion and the pneumatic portion,

wherein the non-pneumatic portion includes:

a band portion including an inner band coupled to an outer circumferential surface of the pneumatic portion and an outer band spaced apart from the inner band, the band portion surrounding an outer circumferential surface of the inner band; and

spokes provided between the inner band and the outer band to connect the inner band and the outer band,

wherein each of the spokes includes:

a first member connected at one end to an inner circumferential surface of the outer band and at the other end to an outer circumferential surface of the inner band;

a second member circumferentially spaced apart from the first member and connected at one end to the inner circumferential surface of the outer band and at the other end to the outer circumferential surface of the inner band; and

a third member configured to connect the first member and the second member,

wherein a space is defined by the first member, the second member, and the third member of the spokes, the space being continuously extended in an axial direction of the semi-pneumatic tire along an entire axial width of the non-pneumatic portion,

wherein a sound-absorbing material is inserted to be entirely accommodated in the space,

wherein an external shape of the sound-absorbing material and a shape of the space are complementary to each other,

wherein the space includes a first space and a second space radially outward from the first space,

wherein a plurality of insertion grooves are formed on the outer circumferential surface of the pneumatic portion, and a plurality of insertion projections to be inserted into the insertion grooves are formed on an inner circumferential surface of the inner band,

wherein each of the insertion projections is formed so that a pneumatic portion side cross-sectional area is larger than an inner band side cross-sectional area, and

wherein an entire inner circumferential surface of the inner band makes surface contact with the outer circumferential surface of the pneumatic portion.

2. The semi-pneumatic tire of claim 1 , wherein the insertion projections are made of the same material as the inner band and integrally formed with the inner band.

3. The semi-pneumatic tire of claim 1 , wherein an external shape of the insertion projections and an internal shape of the insertion grooves are complementary to each other, and outer surfaces of the insertion projections make close contact with inner surfaces of the insertion grooves.

4. The semi-pneumatic tire of claim 1 , wherein the spokes are repeatedly provided to be spaced apart in a circumferential direction, and a circumferential cross-sectional shape of a region between the spokes disposed adjacent to each other is a polygonal shape.

5. The semi-pneumatic tire of claim 1 , wherein the third member is configured to connect central portions of the first member and the second member, and the first member and the second member are bent about the central portions.

6. The semi-pneumatic tire of claim 1 , wherein the sound-absorbing material includes a laminated fiber material obtained by laminating a high-density fiber material and a low-density fiber material.

7. The semi-pneumatic tire of claim 1 , wherein the sound-absorbing material includes a porous material.

8. The semi-pneumatic tire of claim 1 , wherein the sound-absorbing material is exposed to an outside of the semi-pneumatic tire.