Lubricating means for chain saw bar

Claim 1

In a chain saw, the combination of, a guide bar having a pair of sideplates and a center plate rigidly mounted therebetween, each of said plates having longitudinal side edges extending along the opposite sides of the longitudinal centerline of the guide bar, and an endless saw chain mounted upon said guide bar and comprising a series of interconnected side links and center links, said edges of said sideplates upon each side of the guide bar presenting supporting surfaces in the single plane upon which the side links of the chain saw move along and are supported, each side edge of said center plate being spaced inwardly with respect to the adjacent side edges of said sideplates whereby a groove is provided said center links having tangs which are positioned within and move along said groove from a driving sprocket to the nose end of the guide bar, said groove having a depth which is generally greater than the distance of said tangs extend therein whereby the bottom ends of said tangs move along a path which is spaced from the bottom of said groove, said guide bar including a lubricating hole in one of said sideplates extending to said groove to deliver lubricant at a level in said groove adjacent the lower portion of the tangs and said groove being shallow adjacent said lubricating hole with the bottom of the groove being formed by retainer means presenting a surface which is at substantially the level of the path of the lower ends of the tangs whereby lubricant entering said hole is delivered to said surface and is picked up and carried away by the movement of the tangs past said hole.