Abstract: A flexible member is provided which can have excellent load resistance and flexibility while being more compact. This flexible member has a main body part in which multiple wave washers having closed ring shapes is stacked in an axial direction and joined to each other by multiple joint parts, and the main body part is able to be bent with respect to the axial direction due to elastic deformation of the wave washers. Each of the joint parts includes: a pair of welded parts in linear shape, being gradually separated from each other in a circumferential direction from an inner circumferential side toward an outer circumferential side of the wave washer.

Abstract: Provided are a bending structure and a joint function part, capable of stabilizing bending operation and simplifying a structure. An inner coiled part is located into an outer coiled part. The outer coiled part and the inner coiled part have a plurality of gaps distancing adjacent coils in an axial direction, and the coils of the inner coiled part fit between the adjacent coils of the outer coiled part while being in contact with the adjacent coils. A dimension P is set in a range meeting ?R/4N?P<d??R/4N in which P is the dimension of the gap of the outer coiled part in the axial direction in a free state, N is the number of turns of the outer coiled part, R is a diameter of the outer coiled part, and d is a wire diameter of the wire of the inner coiled part.

Abstract: Provided are a bending structure and a flexible tube for a medical manipulator, which comprise a main body that is composed of the wave washers stacked in an axial direction and kept a stacked state, the main body being bendable according to the expansion and contraction in the axial direction. Accordingly, linearity of load characteristics based on load and a bending angle is made high to make it possible to obtain the flexible tube having superior load bearing and bendability while conducting size reduction.

Abstract: A joined body includes: a thin plate including through holes; a first member including a proximal portion having a portion contacting the thin plate, and a protruding portion that protrudes in relation to a contact surface of the proximal portion and is inserted through the through hole; and a second member arranged oppositely to the proximal portion via the thin plate and made of a material that is same as that of the first member. The thin plate is made of a material having a specific gravity smaller than that of the material forming the first and the second members. The second member and an end portion of the protruding portion are connected to each other, by a part of the second member and a part of the end portion being melt-solidified, the end portion being at a side opposite to a side connected to the proximal portion.

Abstract: Provided is a bending structure and a joint function part, capable of ensuring sufficient flexibility and rigidity in an axial direction. The bending structure is provided with an outer coiled part formed of a wire wound in a coiled shape and an inner coiled part formed of a wire wound in a coiled shape and arranged in the outer coiled part, wherein the outer coiled part has a plurality of gaps to distance adjacent coils, and coils of the inner coiled part are provided so as to correspond to the gaps of the outer coiled part and fit between the adjacent coils while being in contact with the adjacent coils of the outer coiled part.

Abstract: A spring consists of, by mass %, 0.5 to 0.7% of C, 1.0 to 2.0% of Si, 0.1 to 1.0% of Mn, 0.1 to 1.0% of Cr, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and inevitable impurities. The spring has a structure including not less than 65% of bainite and 4 to 13% of residual austenite by area ratio in a cross section. The spring has a compressive residual stress layer in a cross section from a surface to a depth of 0.35 mm to D/4, in which D (mm) is a circle-equivalent diameter of the cross section. The spring has a high hardness layer with greater hardness than a center portion by 50 to 500 HV from a surface to a depth of 0.05 to 0.3 mm.

Abstract: Provided is a flexible member that can exhibit excellent load resistance and flexibility while achieving a reduction in size. This flexible member includes: a main body part which has multiple wave washers stacked in an axial direction and joined to each other, and the main body part is able to be bent with respect to the axial direction due to elastic deformation of the wave washers; and a linking member that is elastically deformable, the linking member being provided at an end part of the main body part and being linked to other member. A deformation amount of the linking member is smaller than a deformation amount of the wave washer, when the main body part is bent.

Abstract: A flexible member is provided which can have excellent load resistance and flexibility while being more compact. This flexible member has a main body part in which multiple wave washers having closed ring shapes is stacked in an axial direction and joined to each other by multiple joint parts, and the main body part is able to be bent with respect to the axial direction due to elastic deformation of the wave washers. Each of the joint parts includes: a pair of welded parts in linear shape, being gradually separated from each other in a circumferential direction from an inner circumferential side toward an outer circumferential side of the wave washer.

Abstract: The present invention provides a flexible member having excellent load resistance and flexibility while achieving a reduction in size. This flexible member is provided with: a main body part which includes multiple wave washers that are stacked in an axial direction and are joined to one another by multiple joint parts, and which is capable of bending relative to the axial direction by elastic deformation of the wave washers; and easily deformable parts formed between the joint parts that are adjacent to one another in the circumferential direction in each wave washer.

Abstract: An instrument for a surgical assistance robot is provided with a bending structure that enables a joint function part to be bent and is provided with an outer coiled part formed of a wire wound in a coiled shape and an inner coiled part formed of a wire wound in a coiled shape and arranged in the outer coiled part, wherein the outer coiled part has a plurality of gaps to distance adjacent coils, and coils of the inner coiled part are provided so as to correspond to the gaps of the outer coiled part and fit between the adjacent coils while being in contact with the adjacent coils of the outer coiled part.

Abstract: Provided are a bending structure and a flexible tube for a medical manipulator, which comprise a corrugated tube portion having a corrugated portion in which crests and troughs are alternately arranged in the axial direction and being bendable according to expansion and contraction of the crests and the troughs, and insertion holes provided on the corrugated portion to pass the drive wires in the axial direction.

Abstract: Provided are a bending structure and a flexible tube for a medical manipulator, which comprise a main body that is composed of the wave washers stacked in an axial direction and kept a stacked state, the main body being bendable according to the expansion and contraction in the axial direction. Accordingly, linearity of load characteristics based on load and a bending angle is made high to make it possible to obtain the flexible tube having superior load bearing and bendability while conducting size reduction.

Abstract: A joined body includes: a thin plate including through holes; a first member including a proximal portion having a portion contacting the thin plate, and a protruding portion that protrudes in relation to a contact surface of the proximal portion and is inserted through the through hole; and a second member arranged oppositely to the proximal portion via the thin plate and made of a material that is same as that of the first member. The thin plate is made of a material having a specific gravity smaller than that of the material forming the first and the second members. The second member and an end portion of the protruding portion are connected to each other, by a part of the second member and a part of the end portion being melt-solidified, the end portion being at a side opposite to a side connected to the proximal portion.

Abstract: A spring consists of, by mass %, 0.5 to 0.7% of C, 1.0 to 2.0% of Si, 0.1 to 1.0% of Mn, 0.1 to 1.0% of Cr, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and inevitable impurities. The spring has a structure including not less than 65% of bainite and 4 to 13% of residual austenite by area ratio in a cross section. The spring has a compressive residual stress layer in a cross section from a surface to a depth of 0.35 mm to D/4, in which D (mm) is a circle-equivalent diameter of the cross section. The spring has a high hardness layer with greater hardness than a center portion by 50 to 500 HV from a surface to a depth of 0.05 to 0.3 mm.

Abstract: A surface treatment method for a steel material includes carbonitriding, quenching, and tempering. The steel material consists of, by weight %, 0.27 to 0.48% of C, 0.01 to 2.2% of Si, 0.30 to 1.0% of Mn, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and inevitable impurities. The carbonitriding step is performed by heating the steel at a temperature of not less than the A3 point and not more than 1100° C. and bringing the steel into contact with a mixed gas atmosphere so as to concentrate nitrogen and carbon at a surface layer of the steel. The quenching step is performed by cooling the steel to room temperature at a rate of not less than 20° C./second. The tempering step is performed by heating the steel at a temperature of 100 to 400° C.

Abstract: A spring with superior fatigue resistance is provided by decreasing the material cost while simplifying the production process. Disclosed is a spring including: a composition consisting of, by mass %, 0.5 to 0.7% of C, 1.0 to 2.0% of Si, 0.1 to 1.0% of Mn, 0.1 to 1.0% of Cr, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and impurities; a structure including not less than 95% of tempered martensitic structure; a compressive residual stress layer formed to a depth of 0.35 mm to D/4, in which D (mm) is a diameter; the compressive residual stress layer having maximum compressive residual stress of 800 to 2000 MPa; a center portion with Vickers hardness of 550 to 700 HV; and a high hardness layer with greater hardness than the center portion.

Abstract: A spring consists of, by weight %, 0.27 to 0.48% of C, 0.01 to 2.2% of Si, 0.30 to 1.0% of Mn, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and inevitable impurities. The spring has a nitrogen compound layer and a carbon compound layer at the surface at a total thickness of not more than 2 ?m. The spring has a center portion with hardness of 500 to 700 HV in a cross section and has a compressive residual stress layer at a surface layer. The compressive residual stress layer has a thickness of 0.30 mm to D/4, in which D (mm) is a circle-equivalent diameter of the cross section, and has maximum compressive residual stress of 1400 to 2000 MPa.

Abstract: A spring with superior fatigue resistance is provided by decreasing the material cost while simplifying the production process. Disclosed is a spring including: a composition consisting of, by mass %, 0.5 to 0.7% of C, 1.0 to 2.0% of Si, 0.1 to 1.0% of Mn, 0.1 to 1.0% of Cr, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and impurities; a structure including not less than 95% of tempered martensitic structure; a compressive residual stress layer formed to a depth of 0.35 mm to D/4, in which D (mm) is a diameter; the compressive residual stress layer having maximum compressive residual stress of 800 to 2000 MPa; a center portion with Vickers hardness of 550 to 700 HV; and a high hardness layer with greater hardness than the center portion.

Abstract: A spring consists of, by mass %, 0.5 to 0.7% of C, 1.0 to 2.0% of Si, 0.1 to 1.0% of Mn, 0.1 to 1.0% of Cr, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and inevitable impurities. The spring has a structure including not less than 65% of bainite and 4 to 13% of residual austenite by area ratio in a cross section. The spring has a compressive residual stress layer in a cross section from a surface to a depth of 0.35 mm to D/4, in which D (mm) is a circle-equivalent diameter of the cross section. The spring has a high hardness layer with greater hardness than a center portion by 50 to 500 HV from a surface to a depth of 0.05 to 0.3 mm.

Abstract: A spring consists of, by weight %, 0.27 to 0.48% of C, 0.01 to 2.2% of Si, 0.30 to 1.0% of Mn, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and inevitable impurities. The spring has a nitrogen compound layer and a carbon compound layer at the surface at a total thickness of not more than 2 ?m. The spring has a center portion with hardness of 500 to 700 HV in a cross section and has a compressive residual stress layer at a surface layer. The compressive residual stress layer has a thickness of 0.30 mm to D/4, in which D (mm) is a circle-equivalent diameter of the cross section, and has maximum compressive residual stress of 1400 to 2000 MPa.