A compression coil spring having high durability can be provided by using an inexpensive wire material. The present invention provides a compression coil spring formed by using a steel wire material, the steel wire material made of C: 0.45 to 0.85 mass %, Si: 0.15 to 2.5 mass %, Mn: 0.3 to 1.0 mass %, Fe and inevitable impurities as a remainder, and a circle-equivalent diameter of 1.5 to 9.0 mm, wherein hardness of a freely selected cross-section of the wire material is 570 to 700 HV, and at an inner diameter side of the coil spring, unloaded compressive residual stress at a depth of 0.2 mm from a surface in an approximate maximal main stress direction in a case in which compressive load is loaded on the spring is 200 MPa or more, and unloaded compressive residual stress at a depth of 0.4 mm from surface is 100 MPa or more.

A control method and a device for a cutter shaped by a helical spring includes two controlling apparatuses (20) connected to two coil spring bending tools (10) respectively and including a lifting apparatus (30). The two controlling apparatuses (20) are arranged in the same assembly platform (40). The controlling apparatus (20) controls an amount of displacement of the stretching and retracting of the two coil spring bending tools (10). The amount of displacement of the coil spring bending tools (10) and the amount of up and down movement of the assembly platform (40) are controlled simultaneously by a motor (50). By applying the concept of relative coordinates, the requirements of control can be simplified from two two-dimensional control movements to three single-axis linear movements by using the coordinate of the center point (P3) of a spring coil as the origin of the coordinates for the movement of the spring outer diameter cutter. In the case that the distances of linear movement on the three axes are identical or at a fixed ratio, the advantage of reducing the number of motors is achieved.

A control method and a device for a cutter shaped by a helical spring includes two controlling apparatuses (20) connected to two coil spring bending tools (10) respectively and including a lifting apparatus (30). The two controlling apparatuses (20) are arranged in the same assembly platform (40). The controlling apparatus (20) controls an amount of displacement of the stretching and retracting of the two coil spring bending tools (10). The amount of displacement of the coil spring bending tools (10) and the amount of up and down movement of the assembly platform (40) are controlled simultaneously by a motor (50). By applying the concept of relative coordinates, the requirements of control can be simplified from two two-dimensional control movements to three single-axis linear movements by using the coordinate of the center point (P3) of a spring coil as the origin of the coordinates for the movement of the spring outer diameter cutter. In the case that the distances of linear movement on the three axes are identical or at a fixed ratio, the advantage of reducing the number of motors is achieved.

Apparatus for forming wire components, which are in this example springs, comprises a supply station (202), for supplying spring forming material, such as metallic wire W. The supply station includes a pair of guide rollers (204) and pair of driven feed rollers (206), mounted on a heavy support plate (216). The wire is fed through a flexible sheath FS to a remotely located wire shaping device, in particular a spring forming device 208, comprising forming tools (210), a pitch control tool (212) and a cutter (214). The forming tools (210) and the pitch control tool (212) form the wire into a spring S, which is cut from the supply of wire when it is complete. The tools (210, 212) and cutter (214) are controlled remotely from a control station (220) via a bundle of flexible control cables (222), which may include a power cable. The spring forming device 208 is mounted on a positioning member (224), such as a robot arm or moveable table, configured for three-dimensional movement, and/or optionally adjustments in inclination. Without the heavy plate (216) and rollers (205, 206), the spring forming device (208) is sufficiently light in weight and compact as to be moved by the positioning member (224) to a location in which springs are to be used, thereby avoiding the need for transportation apparatus to convey the springs from the place where they are formed to the place where they are to be used.

Apparatus for forming wire components, which are in this example springs, comprises a supply station (202), for supplying spring forming material, such as metallic wire W. The supply station includes a pair of guide rollers (204) and pair of driven feed rollers (206), mounted on a heavy support plate (216). The wire is fed through a flexible sheath FS to a remotely located wire shaping device, in particular a spring forming device 208, comprising forming tools (210), a pitch control tool (212) and a cutter (214). The forming tools (210) and the pitch control tool (212) form the wire into a spring S, which is cut from the supply of wire when it is complete. The tools (210, 212) and cutter (214) are controlled remotely from a control station (220) via a bundle of flexible control cables (222), which may include a power cable. The spring forming device 208 is mounted on a positioning member (224), such as a robot arm or moveable table, configured for three-dimensional movement, and/or optionally adjustments in inclination. Without the heavy plate (216) and rollers (205, 206), the spring forming device (208) is sufficiently light in weight and compact as to be moved by the positioning member (224) to a location in which springs are to be used, thereby avoiding the need for transportation apparatus to convey the springs from the place where they are formed to the place where they are to be used.

A wire material for a canted coil spring 1 includes a core wire 10 made of steel with a pearlite structure and a plating layer 20 covering a surface 11 of the core wire 10 and made of copper or a copper alloy. The steel constituting the core wire 10 contains 0.5% to 1.0% by mass of carbon, 0.1% to 2.5% by mass of silicon, and 0.3% to 0.9% by mass of manganese, with the balance being iron and unavoidable impurities.

A wire material for a canted coil spring 1 includes a core wire 10 made of steel with a pearlite structure and a plating layer 20 covering a surface 11 of the core wire 10 and made of copper or a copper alloy. The steel constituting the core wire 10 contains 0.5% to 1.0% by mass of carbon, 0.1% to 2.5% by mass of silicon, and 0.3% to 0.9% by mass of manganese, with the balance being iron and unavoidable impurities.

According to an embodiment, a coil spring is formed of a wire which is helically wound, and includes an end turn portion and an effective portion, and a surface of the wire in the end turn portion includes an area which is softer than a surface of the wire in the effective portion.

Spring rings and closed wire loops each can have two ends that are connected. The connected ends can be welded. The connected ends can be aligned for welding by incorporating complementary surfaces so that when joined, the tip at the first end mate to the tip at the second end. The mating can be self-aligning spatially and radially. The spring rings and the closed wire loops can be used in many applications, including in connector applications and seal applications.

Provided is an electrical dust-collecting filter manufacturing method and an electrical dust-collecting filter. The method includes the steps of: preparing a frame body, a dust-collecting electrode, a discharge electrode, and a discharge frame; assembling the dust-collecting electrode into an assembly hole of the frame body; connecting the discharge frame to the frame body via an insulating member; and arranging the discharge electrode in an axial direction inside the dust-collecting electrode via the discharge frame and fixing the same. The dust-collecting electrode assembling step includes: temporarily elastically deforming the dust-collecting electrode in the radial direction and inserting the same into the assembly hole of the frame body; and pressurizing end parts of both ends of the dust collecting electrode, which protrude out of a plate member when fitted into the assembly hole, in the axial direction such that the end parts are compressed against the surface of the plate member.