Tissue collecting instrument

1. A tissue collecting instrument which cuts and collects tissue, comprising:

a first member formed in a tubular shape and including an internal space and a side hole communicating with the internal space;

a second member inserted into the internal space and configured to be movable relative to the first member;

a first protruding portion provided on the first member and configured to protrude toward the inside of the side hole;

a second protruding portion provided on the second member and configured to protrude in a direction opposite to the first protruding portion;

wherein the tissue is able to enter the internal space through the side hole when the first member and the second member are in a positional relationship in which the first protruding portion and the second protruding portion are spaced apart and facing each other;

wherein a cutaway surface forming a peripheral edge of the side hole comprises:

a first blade surface and a second blade surface which are configured to form the first protruding portion, wherein the first protruding portion comes to a first point along a centerline of the first member, and wherein the second protruding portion comes to a second point along the centerline of the first member;

a first edge surface and a second edge surface which are configured to form an edge portion in a radial direction of the side hole; and

a first end surface and a second end surface which are configured to form an edge portion opposite to the first protruding portion in the side hole;

wherein the first blade surface, the first edge surface, and the first end surface are formed to have a common parallel axis.

2. The tissue collecting instrument according to claim 1 , wherein the second blade surface, the second edge surface, and the second end surface are formed to have another common parallel axis.