Patent ID: 11896790
Assignee: ASAHI INTECC CO., LTD.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. A dilator comprising:
a hollow-shaped shaft comprising (i) a tapered section with an outer diameter of a distal end being smaller than an outer diameter of a proximal end, (ii) a distal end section including a proximal end being located at the distal end of the tapered section and extending toward a distal end side of the tapered section in an axial direction, and (iii) a body section including a distal end being located at the proximal end of the tapered section and extending toward a proximal end side of the tapered section in the axial direction; and
a spirally-arranged protruding portion comprising (i) spirally-arranged protruding sections provided on outer peripheral surfaces of each of the tapered section, the distal end section, and the body section, and (ii) gaps between adjacent spirally-arranged protruding sections along the axial direction of the shaft,
wherein a location being at a terminal distal end side of the spirally-arranged protruding portion and including a distal end of the spirally-arranged protruding portion is a first location and a location being at a proximal end side of the spirally-arranged protruding portion and at the proximal end side relative to the first location and including a proximal end of the spirally-arranged protruding portion is a second location,
at least one of (i) a height of the spirally-arranged protruding portion at the first location gradually decreases toward the distal end side of the spirally-arranged protruding portion, and (ii) a height of the spirally-arranged protruding portion at the second location gradually decreases toward the proximal end side of the spirally-arranged protruding portion, and
a shape of an outer peripheral surface at at least one of the first location and the second location in the spirally-arranged protruding portion is a concave shape.