Sewing machine for making decorative stitch patterns

US4144826A · kind A · utility

Assignee

• Dorina Nahmaschinen GmbH · DE

Inventors

• Bernhard Stehlin · Ettlingen, DE
• Joachim Wilken · Ettlingen, DE

Key dates

• Filing date: Oct 14, 1977
• Grant date: Mar 20, 1979
• Expiry date: Oct 14, 1997

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D05B19/12
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

The sewing machine includes respective setting members for adjusting the overstitch width and the stitch length, with the setting members being adjusted by an actuating mechanism responsive to control signals of a program control system, the control signals corresponding to the stitches to be made. The power for driving the actuating mechanism is derived from the continuously operating main shaft of the sewing machine, through a clutch or clutches whose moment to be transmitted is controllable, such as electromagnetic clutches. In one embodiment of the invention, a single electromagnetic clutch is provided for each setting member and includes a first clutch disk connected to the respective setting member to rotate therewith and a second clutch disk secured to a shaft continuously rotated by the main shaft of the machine. A spiral spring is provided to act to rotate the respective setting member in a direction opposite to the direction of rotation thereof by the associated clutch. In a second embodiment of the invention, two clutches are provided to rotate each setting member, each clutch including a first clutch disk. One clutch includes a second disk rotated by a shaft continuousl…