Abstract: An upstanding support is provided and a rotary grinding head is journaled from the upper end of the support for rotation about a vertical axis. A horizontally disposed support arm is pivotally mounted from the support at one end portion for swinging about a vertical axis and the other free end portion of the support arm has a grooved support wheel journaled therefrom for rotation about a horizontal axis extending transversely of the support arm. The grooved support wheel may have a saw chain trained thereover and the grooved support wheel, during oscillation of the support arm, is swingable into registry with diametrically opposite side portions of the rotary grinding head. Also, a chain tooth engaging and positioning member is supported from each of the opposite side portions of the support arm adjacent the grooved support wheel and swingable into and out of an operative position.

Abstract: A mount is provided and includes structure for supporting a saw chain with a tooth thereof in predetermined position relative to the mount. A support is also provided and a rotary grinding wheel is journaled from the support. Parallelogram linkage structure operatively connects the support end of the mount for relative swinging thereof to bring the periphery of the grinding wheel, and said tooth, into engagement with each other along a path of relative movement extending substantially radially of the wheel and with the axis of rotation of the wheel spaced to one side of a plane in which the tooth is disposed.

Abstract: A support plate is provided and includes a pair of intersecting adjacent side marginal edges disposed at generally 100.degree. to 120.degree. relative to each other and provided with endwise outwardly opening grooves formed therein communicated with each other at adjacent ends. The plate includes a transverse bore formed therethrough whereby the plate may be oscillatably supported from a swingable arm of a saw chain sharpener for movement of the plate toward and away from the rotary grinding wheel of the sharpener. Adjustment structure is supported from the plate for adjustably limiting angular displacement of the plate in one direction relative to the corresponding swing arm. The grooves formed in the plate are provided to guidingly and slidingly receive the guide lugs of an associated saw chain and the plate includes adjustable abutment structure engageable with successive saw chain teeth to limit shifting of an associated saw chain relative to the plate along the grooves.

Abstract: A support is provided and a rotary grinding head is journaled from the support for rotation about a first predetermined axis. A support arm is pivotally mounted at one end from the support for swinging of the support and support arm about a second axis substantially paralleling the first axis and the other free end portion of the support arm includes structure for supporting a saw chain therefrom for successive positioning of the cutting teeth of the chain in predetermined position for sharpening by the grinding wheel. As a result of relative swinging of the support and the support arm, the rotary grinding head is swingable into registry opposite side portions of the supported saw chain. Also, a chain tooth engaging and positioning member is supported from the support arm for establishing the predetermined position of the tooth to be sharpened and is swingable into and out of an operative position.

Abstract: A support is provided from which a drivable rotary grinding wheel is journaled for rotation about a first predetermined axis. A mount is also provided and is supported from the support from guided back and forth shifting relative thereto toward and away from the outer periphery of the grinding wheel along a predetermined path extending at least generally radially of the axis of rotation of the grinding wheel. The support means also supports the mount for limited oscillation of the mount about a second axis generally paralleling the first mentioned axis and the mount includes structure operative to support a length of saw chain therefrom.