Abstract: There is provided a method of manufacturing a variable wall thickness steel pipe with a hollow tubular raw pipe. The method of manufacturing a variable wall thickness steel pipe includes locking the raw pipe in a die by thrusting a plug into the raw pipe from an one end side, so as to expand an outer shape on the one end side in a state, where the raw pipe is disposed inside the die and movement of the raw pipe in a longitudinal direction is restricted; and performing ironing in which an inner shape of the raw pipe is expanded while the outer shape is maintained so that a thin portion is formed by further thrusting the plug toward the other end side of the raw pipe while the locked state of the raw pipe is maintained, whereas the restriction on the raw pipe is relaxed.

Abstract: A mandrel 10 for producing a thin-walled bent tube having a bending portion with high strength and a small radius of curvature by rotary draw bending without either cracks in an outside of bend or winkles and buckling in an inside of bend occurring includes a shank 14, a connection mechanism 15 and a mandrel ball 16. In a cross-section orthogonal to an axial direction of the mandrel ball 16 at a central position in the axial direction of the mandrel ball 16, the mandrel ball 16 has a first position 19 and a second position 20 at which a first straight line m that passes through a mandrel ball center 17 meets an outer periphery 21 of the mandrel ball. Further, a ratio (L1/L2) between a dimension L1 from the mandrel ball center 17 to the first position 19 and a dimension L2 from the mandrel ball center 17 to the second position 20 is in a range of 0.915 to 0.976.

Abstract: A mandrel 10 for producing a thin-walled bent tube having a bending portion with high strength and a small radius of curvature by rotary draw bending without either cracks in an outside of bend or winkles and buckling in an inside of bend occurring includes a shank 14, a connection mechanism 15 and a mandrel ball 16. In a cross-section orthogonal to an axial direction of the mandrel ball 16 at a central position in the axial direction of the mandrel ball 16, the mandrel ball 16 has a first position 19 and a second position 20 at which a first straight line m that passes through a mandrel ball center 17 meets an outer periphery 21 of the mandrel ball. Further, a ratio (L1/L2) between a dimension L1 from the mandrel ball center 17 to the first position 19 and a dimension L2 from the mandrel ball center 17 to the second position 20 is in a range of 0.915 to 0.976.

Abstract: A mandrel 10 for producing a thin-walled bent tube having a bending portion with high strength and a small radius of curvature by rotary draw bending without either cracks in an outside of bend or winkles and buckling in an inside of bend occurring includes a shank 14, a connection mechanism 15 and a mandrel ball 16. In a cross-section orthogonal to an axial direction of the mandrel ball 16 at a central position in the axial direction of the mandrel ball 16, the mandrel ball 16 has a first position 19 and a second position 20 at which a first straight line m that passes through a mandrel ball center 17 meets an outer periphery 21 of the mandrel ball. Further, a ratio (L1/L2) between a dimension L1 from the mandrel ball center 17 to the first position 19 and a dimension L2 from the mandrel ball center 17 to the second position 20 is in a range of 0.915 to 0.976.

Abstract: There is provided a method of manufacturing a variable wall thickness steel pipe with a hollow tubular raw pipe. The method of manufacturing a variable wall thickness steel pipe includes locking the raw pipe in a die by thrusting a plug into the raw pipe from an one end side, so as to expand an outer shape on the one end side in a state, where the raw pipe is disposed inside the die and movement of the raw pipe in a longitudinal direction is restricted; and performing ironing in which an inner shape of the raw pipe is expanded while the outer shape is maintained so that a thin portion is formed by further thrusting the plug toward the other end side of the raw pipe while the locked state of the raw pipe is maintained, whereas the restriction on the raw pipe is relaxed.

Abstract: A camshaft-manufacturing method includes: a split die group preparation step; a processing preparation step of preparing a cam including a through-hole, a cam body which is smaller than each of the cam accommodation portions, and ribs which are provided on both sides in a thickness direction of the cam body and configured to be fitted into the rib accommodation portions, and a hollow shaft, accommodating the cam body in the cam accommodation portion and fitting the ribs in the rib accommodation portion, and inserting the hollow shaft into the through-hole of the cam; and a processing step of performing hydroform processing, and fixing the cam to the hollow shaft by expanding the hollow shaft.

Abstract: A camshaft-manufacturing method includes: a split die group preparation step; a processing preparation step of preparing a cam including a through-hole, a cam body which is smaller than each of the cam accommodation portions, and ribs which are provided on both sides in a thickness direction of the cam body and configured to be fitted into the rib accommodation portions, and a hollow shaft, accommodating the cam body in the cam accommodation portion and fitting the ribs in the rib accommodation portion, and inserting the hollow shaft into the through-hole of the cam; and a processing step of performing hydroform processing, and fixing the cam to the hollow shaft by expanding the hollow shaft.

Abstract: The present invention is directed to automatic generation of an operating button for instructing a processing to be executed by a computer on the basis of latest data and display thereof on a display unit, and comprises setting a button class corresponding to an arbitrary field of a plurality of data composed of a plurality of fields and stored in a memory, setting a button group that groups data values classified by the button classes and stored in the memory and individual buttons that correspond to the respective data values and displaying the button group and the individual buttons as an operating button on a display unit. The present invention not only enables the user to implement selection and direction by means of an operating button readily within a short time without the need of operation-related processing software for a menu, buttons, etc. but also facilitates maintenance.