A coil spring manufacturing device includes a mandrel around which a wire is wound, a feed mechanism which feeds the wire toward the mandrel, guide members which guide the wire, a chuck which fixes a distal end of the wire, and a clamp mechanism. The clamp mechanism sandwiches the wire from both sides before the distal end of the wire reaches the mandrel. Further, the clamp mechanism can be rotated about a fulcrum by rotation actuator, and can also be slid in a direction along an axis of the mandrel by sliding actuator. In a state in which the wire is sandwiched by the clamp mechanism, the clamp mechanism is rotated, and if necessary, is slid. Thereby, a bent portion for a negative pitch portion of a coil spring is formed at a part of the wire.

A coiling machine includes a material guide, first pin, second pin, pitch tool, cutting tool, heating device, temperature sensor, and controller. A material is bent between the first pin and the second pin to form an arc part between the first pin and the second pin. The controller select control data corresponding to the temperature of the material from a plurality of control data corresponding to a processing temperature. Then, the positions of the first pin and the second pin are controlled such that a radius of curvature of the arc part increases when the temperature of the material increases, and the position of the cutting tool is controlled such that a gap between the center of curvature of the arc part and the cutting tool increases.

A coiling machine includes a material guide, first pin, second pin, pitch tool, cutting tool, heating device, temperature sensor, and controller. A material is bent between the first pin and the second pin to form an arc part between the first pin and the second pin. The controller select control data corresponding to the temperature of the material from a plurality of control data corresponding to a processing temperature. Then, the positions of the first pin and the second pin are controlled such that a radius of curvature of the arc part increases when the temperature of the material increases, and the position of the cutting tool is controlled such that a gap between the center of curvature of the arc part and the cutting tool increases.

A method is provided for verifying operative parameters of a selecting device of a machine for forming springs, configured for subdividing the springs formed by a spring forming device of a spring forming machine in at least one first group corresponding to springs having dimensional parameters falling into predefined tolerance values, and a second group corresponding to springs having dimensional parameters varying from the predefined tolerance values.

In order to manufacture an innerspring unit comprising pocketed springs and having an increased stability at its edge regions, in a first step, an innerspring main body comprising a plurality of first strings of pocketed springs is provided. In a subsequent second step, at least one second string of pocketed springs is attached to a lateral surface of the innerspring main body, so that the at least one second string of pocketed springs extends in a longitudinal direction of the innerspring main body. The springs of the at least one second string of pocketed springs have a spring characteristic or a spring geometry different from the springs of the plurality of first strings of the innerspring main body. The at least one second string of pocketed springs forms together with the innerspring main body the innerspring unit.

A tool holder configuration structure for spring making machine includes a flat base plate and three displacement mechanisms arranged on the front side in a triangle, each displacement mechanism including a first sliding tract set and a second sliding tract set arranged at right angles, and three tool holder panels each said tool holder panel including a base, a first tool holder located on one side of the base and two second tool holders obliquely disposed at two opposite lateral sides of the first tool holder. The tool holder panels are respectively coupled to the second sliding tract sets of the displacement mechanisms to keep the first tool holders adjacent to one another so that the moving distance of the tool holder panels can be minimized and a large number of tools can be installed in each tool holder panel.

A tool holder configuration structure for spring making machine includes a flat base plate and three displacement mechanisms arranged on the front side in a triangle, each displacement mechanism including a first sliding tract set and a second sliding tract set arranged at right angles, and three tool holder panels each said tool holder panel including a base, a first tool holder located on one side of the base and two second tool holders obliquely disposed at two opposite lateral sides of the first tool holder. The tool holder panels are respectively coupled to the second sliding tract sets of the displacement mechanisms to keep the first tool holders adjacent to one another so that the moving distance of the tool holder panels can be minimized and a large number of tools can be installed in each tool holder panel.

The present invention relates to a hot coiling machine, and an object of the invention is to provide a hot coiling machine that produces coil springs having various coil shapes and diameters from a heated wire without a mandrel. The present invention provides a hot coiling machine including: a center roll rotating by a drive unit; a feeding roll disposed near the center roll and facing an external surface of the center roll, the center roll being configured to move by a first positioning unit and being rotated by a drive unit thus moving a wire together with the center roll; a forming roll for forming the wire into a coil shape; and a pitch control unit disposed near the forming roll to come into contact with the coiled wire and pushing the coiled wire to provide the coiled wire with a desired pitch.

The present invention relates to a hot coiling machine, and an object of the invention is to provide a hot coiling machine that produces coil springs having various coil shapes and diameters from a heated wire without a mandrel. The present invention provides a hot coiling machine including: a center roll rotating by a drive unit; a feeding roll disposed near the center roll and facing an external surface of the center roll, the center roll being configured to move by a first positioning unit and being rotated by a drive unit thus moving a wire together with the center roll; a forming roll for forming the wire into a coil shape; and a pitch control unit disposed near the forming roll to come into contact with the coiled wire and pushing the coiled wire to provide the coiled wire with a desired pitch.

Provided is a continuous heating device for coil springs and a continuous heating method for coil springs using the same. The device may include: a pair of tapered rollers configured to support and rotate the coil spring, configured to have a cross-sectional diameter that increases as it goes from the front end portion to the rear end portion, and configured to have rotational inner surfaces that are arranged to be parallel with each other while the central rotation axes thereof are not parallel with each other; a conveyor chain configured to have a push rod that is installed therein to move the coil spring; and a driving unit configured to provide a rotational driving force to the pair of tapered rollers.