US 9,808,279 B2
Medical knife
Makoto Mori, Seki (JP); Hidetoshi Amemoto, Seki (JP); and Kazuyuki Hasebe, Seki (JP)
Assigned to KAI R&D CENTER CO., LTD., Gifu-ken (JP)
Appl. No. 14/110,503
Filed by Makoto Mori, Seki (JP); Hidetoshi Amemoto, Seki (JP); and Kazuyuki Hasebe, Seki (JP)
PCT Filed Apr. 27, 2012, PCT No. PCT/JP2012/061406
§ 371(c)(1), (2), (4) Date Oct. 8, 2013,
PCT Pub. No. WO2012/147934, PCT Pub. Date Nov. 1, 2012.
Claims priority of application No. 2011-100960 (JP), filed on Apr. 28, 2011.
Prior Publication US 2014/0031847 A1, Jan. 30, 2014
Int. Cl. A61B 17/3211 (2006.01); A61F 9/013 (2006.01)
CPC A61B 17/3211 (2013.01) [A61F 9/0133 (2013.01); F04C 2270/0421 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A medical knife comprising:
a handle having a grip portion and extending in one direction;
a blade plate extending from the handle in a manner intersecting the handle, the blade plate including a distal end and a proximal end; and
a blade portion formed at the distal end of the blade plate, wherein
the blade portion has a front-face portion and a back-face portion, the front-face portion being formed on an upper side in a thickness direction of the blade plate where the grip portion is arranged, the back-face portion being formed on a lower side in the thickness direction of the blade plate opposite to the grip portion,
four blade surfaces in total are formed at two sides in a width direction of the blade plate intersecting the thickness direction of the blade portion in both the front-face portion and the back-face portion of the blade portion, each side in the front-face portion having a single blade surface, each side in the back-face portion having a single blade surface, the blade surfaces being inclined from a middle portion in the width direction to opposite outer ends in the width direction in the blade plate to cooperatively decrease a thickness dimension,
an outer end at which each one of the blade surfaces of the front-face portion and the corresponding one of the blade surfaces of the back-face portion cross each other form a cutting edge extending from the distal end to the proximal end of the blade portion,
each blade surface of the front-face portion and the back-face portion is defined by the corresponding cutting edge and an opposite side formed on the front-face portion and the back-face portion,
the two blade surfaces in the width direction of the back-face portion of the blade portion are formed to gradually increase a distance between the opposite side and the cutting edge from one of the distal end and the proximal end to the other, and
the two blade surfaces in the width direction of the front-face portion of the blade portion are formed such that the distance between the opposite side and the cutting edge becomes uniform over the entire cutting edge from the distal end to the proximal end of the cutting edge,
in the front-face portion and the back-face portion of the blade portion, a boundary between the opposite blade surfaces in the width direction is formed between a point at which the cutting edges of the blade surfaces in the width direction cross each other and a peak at which the opposite sides of the blade surfaces in the width direction cross each other, a middle surface being formed between the opposite sides of the blade surfaces in the width direction,
in the blade plate, the cutting edges in the width direction of the blade portion extend from the point to an end, a maximum width-direction distance is defined between the ends of the cutting edges in the width direction,
the distance between the opposite side and the cutting edge in each blade surface in the width direction of the back-face portion of the blade portion is greater than the distance between the opposite side and the cutting edge in each blade surface in the width direction of the front-face portion of the blade portion, and
the inclination angle between each blade surface of the front-face portion of the blade portion and a plane including the cutting edge in the width direction is set to a value greater than the inclination angle between each blade surface of the back-face portion of the blade portion and said plane.