GB457743A - Sewing and trimming machine - Google Patents

Abstract

457,743. Sewing-machines. FAIRWEATHER, W. C., 65, Chancery Lane, London.- (Singer Manufacturing Co. ; Elizabeth, New Jersey, U.S.A.) July 2, 1936, No. 18331. [Class 112] The driving mechanism of the trimming device described in Specification 455,001 is modified by improved mounting of the electric motor and its couplings to the knife-actuating shaft. Lubrication devices are also provided. The feed and needlevibrating mechanisms are the same as those described in Specification 374,322. A bracket 20 provides bearings for the knife bar 21 carrying the knife 23 which severs the work parallel to the line of seam formation. The knife bar 21 is reciprocated by the bar 28 via a link 26 and collar 25, when the pin 31 on the crank-arm 32 on the rock-shaft 33 is engaging with the slot 30 in the bar. The shaft 33 can move axially and has a circumferential groove 35 embraced by a notched yoke 36 on the hand lever 37 for disengaging the pin 31 and slot 30. The pin and slot are re-engaged to put the trimmer into action by a lever 43 having an extension 45 which engages the upper end of the knife bar to depress it till the pin enters the notch. The shaft 33 is rocked by the electric motor 73 which is independent of the motor driving the sewing machine. The shaft 33 carries a rock-arm with arms 51, 52 with a pitman 58 between them. The opposite end of this pitman embraces a crank-pin 59 extending from the disc 60 at the end of the rotating shaft 61. This shaft is driven from the motor 73 by the belt 70 and pulley 69. The cutter mechanism can be put out of action by the lever 43 or by stopping the motor 73. Its speed may be varied independently of that of the sewing machine. The machine may trim without sewing by removing the sewing-needle. Lubricating. The arms 51, 52 receive a pin 53 with a longitudinal bore 54 receiving a lubricating wick 55, the bore 54 being intersected by radial ducts 56. To supply lubricant to the bearings of the shaft 61, the bracket lugs 65, 66 are provided with bosses 77 with nipples 83 communicating with wells 79 containing a wick 82, Fig. 5, supplying oil to the grooves 84 in the bushing. The pitman 58 also has a longitudinal groove of which the upper end is enlarged to form an oil reservoir. A C-shaped oil guard bracket 91 collects lubricant in its base and prevents splashes being thrown off.