Medical hollow needle and a method of producing thereof

A method of producing a medical hollow needle, said method comprising:

• grinding a top edge portion of a cylindrical member defining a flow path capable of passing a fluid therein along a center axis direction, in an oblique direction with respect to said center axis direction of said cylindrical member, thinning wall thickness of said cylindrical member, so as to form a fourth bevel grinding face in the shape of a plane;
• performing a grinding machining on a portion opposed to said fourth bevel grinding face of said top edge portion of said cylindrical member formed said fourth bevel grinding face, in an oblique direction, having a first inclined angle with respect to said center axis so as to form a first bevel grinding face in which said flow path is open in an oblique direction;
• performing a grinding machining on said top edge portion of said cylindrical member by rotating a first rotational angle in a positive direction with respect to said first bevel grinding face with said axis center as its center, having a second inclined angle with respect to said center axis so as to form a second bevel grinding face, and by rotating a second rotational angle in an opposite direction with respect to said first bevel grinding face with said axis center as its center, having a third inclined angle with respect to said center axis so as to form a third bevel grinding face, respectively;
• and
• forming a sharp edge portion comprised of at least said second, said third and said fourth bevel grinding faces.

A method of producing a medical hollow needle, said method comprising:

• performing a grinding machining on a top edge portion of a cylindrical member formed a flow path capable of passing a fluid therein in its center axis direction, in an oblique direction having a first inclined angle with respect to said center axis so as to form a first bevel grinding face in which said flow path is open in an oblique direction;
• performing a grinding machining on said top edge portion of said cylindrical member by rotating a first rotational angle in a positive direction with respect to said first bevel grinding face with said axis center as its center, having a second inclined angle with respect to said center axis so as to form a second bevel grinding face, and by rotating a second rotational angle in an opposite direction with respect to said first bevel grinding face with said axis center as its center, having a third inclined angle with respect to said center axis so as to form a third bevel grinding face, respectively;
• grinding a position opposed to said first bevel grinding face of said top edge portion of said cylindrical member in an oblique direction with respect to said center axis, thinning a wall thickness of said cylindrical member so as to form a fourth bevel grinding face in the shape of a plane;
• and
• forming a sharp edge portion comprised of at least said second, said third and said fourth bevel grinding faces.

A method of producing a medical hollow needle, said method comprising:

• performing a grinding machining on a top edge portion of a cylindrical member forming a flow path capable of passing a fluid therein in its center axis direction, in an oblique direction having a first inclined angle with respect to said center axis so as to form a first bevel grinding face in which said flow path is open in an oblique direction;
• grinding a position opposed to said first bevel grinding face of said top edge portion of said cylindrical member in an oblique direction with respect to said center axis, thinning wall thickness of said cylindrical member so as to form a fourth bevel grinding face in the shape of a plane;
• performing a grinding machining on said top edge portion of said cylindrical member by rotating a first rotational angle in a positive direction with respect to said first bevel grinding face with said axis center as its center, having a second inclined angle with respect to said center axis so as to form a second bevel grinding face, and by rotating a second rotational angle in an opposite direction with respect to said first bevel grinding face with said axis center as its center, having a third inclined angle with respect to said center axis so as to form a third bevel grinding face, respectively;
• and
• forming a sharp edge portion comprised of at least said second, said third and said fourth bevel grinding faces.

A method of producing a medical hollow needle, said method comprising:

• performing a grinding machining on a top edge portion of a cylindrical member forming a flow path capable of passing a fluid therein in its center axis direction by rotating a first rotational angle in a positive direction with respect to a predetermined standard position with said axis center as its center, having a second inclined angle with respect to said center axis so as to form a second bevel grinding face, and by rotating a second rotational angle in an opposite direction with respect to said standard position with said axis center as its center, having a third inclined angle with respect to said center axis so as to form a third bevel grinding face, respectively;
• grinding a position opposed to said standard position of said top edge portion of said cylindrical member in an oblique direction with respect to said center axis direction, thinning wall thickness of said cylindrical member so as to form a fourth bevel grinding face in the shape of a plane;
• performing a grinding machining on said top edge portion of said cylindrical member at said standard position in an oblique direction, having a first inclined angle with respect to said center axis so as to form a first bevel grinding face in which said flow path is open in an oblique direction;
• and
• forming a sharp edge portion comprised of at least said second, said third, and said fourth bevel grinding faces.

A method of producing a medical hollow needle, said method comprising:

• performing a grinding machining on a top edge portion of a cylindrical member formed a flow path capable of passing a fluid therein in its center axis direction by rotating a first rotational angle in a positive direction with respect to a predetermined standard position with said axis center as its center, having a second inclined angle with respect to said center axis so as to form a second bevel grinding face, and by rotating a second rotational angle in an opposite direction with respect to said standard position with said axis center as its center, having a third inclined angle with respect to said center axis so as to form a third bevel grinding face, respectively;
• performing a grinding machining on said top edge portion of said cylindrical member at said standard position in an oblique direction, having a first inclined angle with respect to said center axis so as to form a first bevel grinding face in which said flow path is open in an oblique direction;
• grinding a position opposed to said first bevel grinding face of said top edge portion of said cylindrical member in an oblique direction with respect to said center axis direction, thinning wall thickness of said cylindrical member so as to form a fourth bevel grinding face in the shape of a plane;
• and
• forming a sharp edge portion comprised of at least said second, said third, and said fourth bevel grinding faces.