Abstract:
A body portion of the funnel has a first region of dimension h, the dimension h being measured from the seal edge surface in a direction parallel to a tube axis, and a second region excluding the first region. The second region has a thickness relatively smaller than the thickness of the first region, so that a boundary portion between the two regions forms a stepped portion on the external surface of the body portion.
Abstract:
A diagonal inner-face curved portion is formed on an inner face of a diagonal portion of a pyramid-shaped yoke portion. The diagonal inner-face curved portion is formed to make at least one of partially inner-face curved portions at the major axis side and the minor axis side of the diagonal axis swell to the outward side. The partially inner-face curved portions at the major axis side and the minor axis side are formed by circular arced portions with different radii to each other.
Abstract:
A body portion of the funnel, within a range excluding corners, has a first region of predetermined dimension, the predetermined dimension being measured from the seal edge surface in a direction parallel to a tube axis, and a second region excluding the first region. The second region has a thickness relatively smaller than the thickness of the first region, so that a boundary portion between the two regions forms a stepped portion on the external surface of the body portion.
Abstract:
The reference surface of the positioning reference on the funnel is formed as a flat plane from a mold match line towards a small-diameter opening side. In addition, the reference surface of the positioning reference is formed in parallel with or in a direction near a central axis line of the funnel from the mold match line towards the small-diameter opening side with respect to a plane which is in parallel with the central axis line and includes the mold match line.