Patent GB-503365-A (GB)
Title: Sewing machine
IPC: D05B71/00
Filed: 1938-03-15
Abstract: 503,365. Sewing - machines. FAIRWEATHER, W. C. (Singer Manufacturing Co.) March 15, 1938, No. 7960. [Class 112] Lock-stitch sewing-machines.-The needle-bar acutating shaft has a longitudinal bore to distribute oil to its bearings, the oil being supplied from a reservoir by a pump driven by the loop-taker actuating shaft. The needlebar actuating shaft 37 is supported in fixed bearings 34, 35 and a self-aligning bearing 36, and is connected to the shaft 94 carrying the loop-taker by a vertical shaft 90 having bevel gearing at each end. The shaft 37 carries the usual crank disc 40 with a pin 41 for the takeup operating link and a return crank-pin 43 for the needle operating link ; both these links have needle bearings on their pins. Lubricating passages, channels, and reservoirs; frames.-The base 28 of the machine is hinged at one side to the table and has depending walls 30 resting on a resilient gasket 27 in a groove in the walls of an oil reservoir 25 fixed to the under side of the table, the frame having no rigid connection with the reservoir ; the groove containing the gasket 27 communicates with the reservoir by drainage grooves 24. A centrifugal pump 99, driven by an extension of the shaft 90, supplies oil through a pipe 106 to the bearing 35 of the shaft 37, whence it passes into the bore of the shaft. At the left-hand end of the shaft a radial passage allows oil to pass from the bore to the bearing 34, a helical groove in the shaft carrying the oil along the bearing, which also has a drainage channel 112 for oil leaking from its front end and falling from a thrower ring 171 on the shaft; the helical groove also carries oil to radial passages in the bearing 34 communicating with a well 114 from which wicks 116, resting in a dish 113 and depending through tubes 117 therefrom, conduct oil to the joints of the take-up and needle-bar actuating mechanisms ; the well has a drainage passage (not shown) for surplus oil. The other end of the bore in the shaft 37 communicates by radial passages and circumferential grooves with the feed-operating eccentrics 56, 64 and the face of the bevel gear 65, whence it passes to the teeth of the gears and falls into a cup 129, then running down the shaft 90 to lubricate the bearings thereof. A thrower ring 172 on the shaft 37 prevents excess of oil passing to the bearing 36. Excess oil from the bearings of the shaft 37 and other parts drains down the standard 31, some of it passing a window in the standard; part of this oil enters the bearing 96<1> of the shaft 94 and part into a trough (not shown) which communicates with the bearing 96. A helical groove in the shaft 94 prevents excess oil from escaping at the front of the bearing 96. To facilitate assembly of the feed-actuating rock-shafts 77, they pass through open notches in the end wall of the machine base, these notches being closed by inserted parts when the shafts are in position ; the shafts are provided with oil-throwing rings 170 to prevent oil from leaking through the apertures in the end wall. Feed, regulating.-The usual four-motion feed dog is actuated by two rock-shafts 77 connected to eccentrics 56, 64 on the shaft 37. The eccentric 64, from which the dog derives its lifting movement, is integral with the gear 65, secured on the shaft by a set screw. The eccentric 56, imparting the feeding movement to the dog, is of variable throw. Presser-bars, lifting.-Knee-eontrol means for lifting the presser-bar are provided, as described in Specification 504,610, comprising a knee-engaging lever (not shown) fixed to a rockshaft 152 carried in arms depending from the oil reservoir 25, a lever 156 on the shaft 152, a push-rod 157 passing up into the oil reservoir and provided with a cap 157<1> to prevent leakage of splashed oil through its bearing, and a lever 159 connected with the presser-bar through a vertical link and a horizontal spring-biassed lever pivoted on the head of the machine.