The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 10, 1981
Filed:
Apr. 28, 1980
Walter Hager, Kaiserslautern, DE;
Karl-Heinz Walther, Weilerback, DE;
Abstract
A thread-cutting device for sewing machines including a housing mounting a reciprocating thread guiding needle which cooperates with a revolving looper comprises a thread catcher adjacent the looper which is movable to engage the thread and to advance the thread past a fixed knife. The catcher is mounted so that it may move relative to the looper and the fixed knife to urge thread held by the catcher into cutting engagement with the knife. Double action fluid pressure operated piston and cylinder is connected to the catcher so as to move it relative to the knife and to the looper. A member is connected to the mechanism between the fluid pressure cylinder operator and the thread catcher and a spring has one end connected to the member and an opposite end mounted on the housing in such a manner that the force of the spring may be adjusted. A fluid pressure operated control has a movable control piston rod which is engageable with the member in an engagement portion thereof such as an opening therethrough. When engaged, it holds the connection between the fluid pressure operated piston rod and the thread catcher against the influence of the spring. When the spring is connected so that it operates through the member moving the catcher, it causes the catcher to be moved during the cutting movement of the thread with some delay so that tearing of the thread is less likely. In a non-operative position, the control member holds the moving mechanism for the thread catcher against the force of the spring.