| US 7,610,787 B2 | ||
| Spring manufacturing apparatus and control method thereof | ||
| Ichiro Itaya, Katsushika-ku (Japan) | ||
| Assigned to Kabushiki Kaisha Itaya Seisaku Sho, Tokyo (Japan) | ||
| Filed on Jul. 26, 2007, as Appl. No. 11/881,452. | ||
| Claims priority of application No. 2006-203670 (JP), filed on Jul. 26, 2006. | ||
| Prior Publication US 2008/0022742 A1, Jan. 31, 2008 | ||
| Int. Cl. B21F 3/02 (2006.01); B21D 43/00 (2006.01); B21F 35/00 (2006.01) | ||
| U.S. Cl. 72—137 [72/135; 72/142; 72/420] | 1 Claim |
| 1. A control method of a spring manufacturing apparatus having: a wire feeder which feeds a wire; a wire guide which guides
the wire fed out of the wire feeder to a spring forming space on a forming table; a tool unit, a plurality of which can be
arranged radially around the spring forming space on the forming table, which supports a tool so that the tool can be slidable
toward the spring forming space; and a grip unit having face-to-face fingers for gripping part of a yet-to-be-cut spring that
has been formed into a partially finished shape in the spring forming space and which can be moved adjacent to an end portion
of the wire guide, said method comprising:
a primary forming step of forming the wire fed out of an end portion of the wire guide into a first coil portion using said
tool;
a gripping step of gripping the first coil portion using the fingers of the grip unit;
a cutting step of cutting the wire which extends from the first coil portion to the wire guide, while the wire is gripped
by the fingers; and
a secondary forming step of forming a yet-to-be formed wire part extending from the first coil portion, which is gripped by
the fingers after being cut, into a second coil portion by winding the yet-to-be formed wire part on a rotational tool while
it is controlled so that a moving speed of the fingers which are gripping the first coil portion is synchronized with the
wire winding speed which is determined by rotation of the rotational tool.
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