Patent ID: 8051788

Claim:
A sewing machine comprising: an upper beam and a lower beam below and spaced from the upper beam in a vertical direction; a head mounted on an end of the upper beam and including a stitching device and a pressing device; a thread hooking mechanism mounted in the lower beam; a needle plate base mounted to an end of the lower beam and located below the head and spaced from the head in the vertical direction; a transmission shaft rotatably extending in the lower beam and having an end extending into the needle plate base, with the transmission shaft adapted to be driven by a power source; and a driving device mounted to the end of the lower beam and including a transmission gear fixed on the end of the transmission shaft, a driven shaft rotatably received in the needle plate base and having an end coupled to the thread hooking mechanism, and a driven gear fixed on the driven shaft and connected to the transmission gear, with the driven shaft and the thread hooking mechanism rotating at a speed higher than the transmission shaft, with the needle plate base including a top plate and a side plate, with the side plate including a plurality of through-holes, with the end of the lower beam including a plurality of screw holes aligned with the plurality of through-holes, with a plurality of bolts extending through the plurality of through-holes into the plurality of screw holes, with the side plate further including a hole, with the end of the transmission shaft extending through the hole, with the end of the lower beam including a first bearing seat receiving a first bearing, and with the end of the transmission shaft extending through the first bearing.