GB467947A - Tension device for sewing machines - Google Patents

Abstract

467,947. Sewing-machines. FAIRWEATHER, W. C. (Singer Manufacturing Co.) June 24, 1936, No. 17517. [Class 112] A tension device for the needle thread has means for adjusting the initial tension of the discs and check spring. The head 10 of the machine has a recess 11 to receive the cylindrical arbor 13 of the tension device, the shank being held by a set screw. The usual check spring 15 is coiled about the arbor with one end 16 anchored in one of eight slots 17 in an enlarged portion of the arbor. The other end of the spring forms a loop for engaging the thread, the movement of the loop being limited by a stop on the plate 20. The slot 17 receiving the spring shank determines its tension. The tension discs 26, 27 are fitted on the arbor between the plate 20 and the plate 28. The plate 28 has a part 29 entering an aperture in the machine, to prevent rotation. Two telescopic members 30, 38 enclose a spring 34. The tension is regulated by rotating the nut 42. This'turns the member 38 by the engagement of the lug 43 in one of the slots 40. The rotation of the nut and member 38 causes them to travel down the arbor causing the spring 34 to press the discs 26, 27 together with out rotations. A usual tension release is provided consisting of a lever 46 and rod 45 operated by the presser lifter.