A method of manufacturing a hollow coil spring which is made of a hollow wire in which a terminal sealed portion is formed on an end portion of the wire. The terminal sealed portion has a rotationally symmetric shape in which an axis passing through the center of the wire is the symmetric axis. The hollow coil spring includes an end wall portion, and an end face arc-shaped curved surface. The end wall portion includes an end face perpendicular to the axis. A distal-end-center closure portion is formed on the axis at the center of the end wall portion. A spring seat includes a base member and a sheet member. An end turn portion of the hollow coil spring is in contact with the sheet member. The end face of the end turn portion is opposed to a stopper wall of the spring seat.

A process for preparing a multi-thickness welded steel vehicle rail, the process comprises the steps of: (a) forming a first tube having a first outer diameter, an inner diameter and a first wall thickness; (b) forming a second tube having the first outer diameter, a second inner diameter and a second wall thickness different than the first wall thickness; (c) swaging a first end of the first tube to a second outer diameter less than the second inner diameter of the second tube; (d) inserting the swaged first end of the first tube into an end of the second tube to form a joint; (e) welding the first tube and the second tube together to form a weld at the joint to form a tube blank with a heat affected zone of lower metal strength in the area of the weld; (f) preheating the tube blank to create a common crystalline microstructure along a length of the tube blank; (g) introducing the tube blank into a blow molding tool having inner molding walls; (h) molding the tube blank at an elevated temperature by expanding the tube blank against the inner molding walls of the molding tool by injecting a pressurized medium into an interior cavity of the tube blank; and (i) quenching the tube blank by replacing the pressurized medium with a cooling medium through the molding tool and the tube blank to achieve a rapid cooling effect on the tube blank and to create a completed vehicle rail with essentially uniform material strength across the weld. A completed vehicle rail has an overlapped welded structure and uniform microcrystalline structure along the length of the rail.

A fitting includes: a first member; a second member coupled by screw coupling with the first member; and a ferrule placed in an accommodation space between the first member, the second member, and a pipe. The ferrule has a rising portion including a first end portion, a pressed portion located closer to a second end portion than the rising portion, and an intermediate portion including a portion where an inner diameter is greater than the first end portion and the second end portion, the intermediate portion connecting together the rising portion and the pressed portion. The first member has a first tapered inner circumferential surface, which is an inner circumferential surface having a tapered shape, to be in contact with the first end portion of the ferrule. The second member has a pressing portion for pressing at least a portion of the pressed portion of the ferrule. The accommodation space provides a clearance for accommodating the ferrule and allowing the rising portion to rise so as to increase an angle of the rising portion.

A fitting includes: a first member; a second member coupled by screw coupling with the first member; and a ferrule placed in an accommodation space between the first member, the second member, and a pipe. The ferrule has a rising portion including a first end portion, a pressed portion located closer to a second end portion than the rising portion, and an intermediate portion including a portion where an inner diameter is greater than the first end portion and the second end portion, the intermediate portion connecting together the rising portion and the pressed portion. The first member has a first tapered inner circumferential surface, which is an inner circumferential surface having a tapered shape, to be in contact with the first end portion of the ferrule. The second member has a pressing portion for pressing at least a portion of the pressed portion of the ferrule. The accommodation space provides a clearance for accommodating the ferrule and allowing the rising portion to rise so as to increase an angle of the rising portion.

According to a method for forming an elliptical hollow cylinder, part of the elliptical hollow cylinder is formed into a circular hollow cylindrical shape by spinning. The forming method includes a first forming process for forming the part of the elliptical hollow cylinder into a circular hollow cylindrical shape by using an inside roller, and a second forming process for reducing a diameter of the part formed into the circular hollow cylindrical shape in the first forming process by using an outside roller. According to the forming method, it becomes possible to shorten time required for forming the part of the elliptical hollow cylinder into a circular hollow cylindrical shape by spinning.

According to a method for forming an elliptical hollow cylinder, part of the elliptical hollow cylinder is formed into a circular hollow cylindrical shape by spinning. The forming method includes a first forming process for forming the part of the elliptical hollow cylinder into a circular hollow cylindrical shape by using an inside roller, and a second forming process for reducing a diameter of the part formed into the circular hollow cylindrical shape in the first forming process by using an outside roller. According to the forming method, it becomes possible to shorten time required for forming the part of the elliptical hollow cylinder into a circular hollow cylindrical shape by spinning.

The present invention relates to a slotless motor including a thin-walled hollow rotor body 100, and methods of manufacture of such rotors, the methods including hot forming and machining steps. The rotor body has a rotational axis 102 and comprises a first cylindrical portion 104 having a first diameter, a second cylindrical portion 106 having a second diameter, larger than the first diameter and a third cylindrical portion 108 having a third diameter, smaller than the second diameter, the third cylindrical portion located at a second end of the rotor body 100. A first end cap 110 joins the first and second cylindrical portions together, and a second end cap 112 joins the first and second cylindrical portions together. The first, second and third cylindrical portions are all arranged coaxially with the rotational axis 102 of the rotor 100 such that the second cylindrical portion 108 and the first and second end caps collectively define a hollow cavity 114 in the rotor body 100. The rotor body 100 may be provided with a Halbach array.

Mufflers with unique configurations which, in certain (but not all) embodiments, improve engine performance. In other embodiments, improved manufacturing processes and methods for making mufflers. In particularly preferred embodiments, methods for making motorcycle mufflers with swaging techniques. In still other preferred embodiments, swaged motorcycle mufflers with improved exhaust flow. In still other embodiments, aftermarket mufflers which can be assembled to a variety of engine exhaust systems utilizing a universal coupler.

The present invention discloses a swaging die holder for the flexible shaft operations. In the preferred embodiment, the swaging die holder comprises of an elliptical die holder slot, a stress relief slot, a radius curve, a recess and an insert. The die holder slot at top of the die holder allows each die holder to mount to the machine. The insert is adapted through the recess at the bottom of each die holder and designed to produce the different output profiles at the end of the flexible shaft. The insert is made of HSS material with cobalt content to achieve optimal life. The insert is further re-grinded or re-sharpened for same or other profile applications of the flexible shaft.

A device for crimping a radially expandable and collapsible prosthetic valve comprises a crimping loop having a first end portion, a second end portion, and a loop portion extending between the first and second end portions and defining an opening configured to receive the prosthetic valve. The crimping loop is movable between a first state in which the opening has a first diameter and a second state in which the opening has a second diameter smaller than the first diameter such that when the prosthetic valve is positioned within the loop portion, movement of the crimping loop from the first state to the second state is effective to reduce a diameter of the prosthetic valve. A method for crimping a prosthetic valve comprises reducing a diameter of an opening of a crimping loop, thereby radially compressing an at least partially expanded prosthetic valve disposed within the opening.