Patent ID: 11919272
Assignee: SUMITOMO RIKO COMPANY LIMITED
Field: Mechanical elements (Mechanical engineering)
Classification: CPC B  F | IPC B  F

Claim 0:
1. A multilayer tube applied to pipelines for an automobile, wherein the multilayer tube is formed of an organic material,
the multilayer tube has:
a first end portion that is connected to a first mating member by inserting the first mating member into the first end portion or by sleeving the first mating member on the first end portion; and
an intermediate part connected to the first end portion, and
the multilayer tube comprises:
an elastic layer formed throughout the entire length of the multilayer tube and having a determined flexural modulus of elasticity; and
a hard layer formed throughout the entire length of the multilayer tube, having a flexural modulus of elasticity higher than that of the elastic layer and disposed radially outward from the elastic layer,
wherein, in a longitudinal direction of the multilayer tube, each of a thickness of the elastic layer and a thickness of the hard layer is varied,
the first end portion of the multilayer tube is formed such that the thickness of the elastic layer is greater than the thickness of the hard layer,
the intermediate part of the multilayer tube in the longitudinal direction has a portion formed such that the thickness of the elastic layer is thinner than the thickness of the hard layer in the longitudinal direction,
a total thickness of the first end portion is greater than a total thickness of the intermediate part,
the thickness of the hard layer in the first end portion is smaller than the thickness of the hard layer in the intermediate part, and
a ratio of the thickness of the elastic layer to the total thickness of the first end portion in the first end portion is greater than a ratio of the thickness of the hard layer to the total thickness of the intermediate part in the intermediate part.