| 摘要 |
<p>An improved self-oiling system for the drive shaft and feed dog assembly of a portable, bag-closing sewing machine utilizes a drive shaft having an internal axial oil channel, an upper radial oil bore which extends from the oil channel to the outer periphery of the shaft to confront the lower main drive shaft bearing, and a lower radial oil passage which extends between the oil channel and the outer periphery of a feed dog eccentric cam which is integral with the lower end of the drive shaft. Oil is supplied to the lower main drive shaft bearing for further downward distribution along the bore, channel and passage to the outer periphery of the feed dog cam which is rotatably received in the feed dog block. An oil passage within the feed dog block delivers oil from the feed dog cam radial oil passage to a slide bearing within the block to lubricate the interface between a guide post and the slide bearing. Annular recesses are provided on the shaft and post to further enhance transfer of oil within the machine. The described oil distribution network utilizes the centrifugal force of the rotating drive shaft and the oscillation of the moving feed dog block to transfer and distribute oil.</p> |
