Chain saw carriage

Claim 1

A portable chain saw attachment for a chain saw to facilitate cutting a reclined log into lumber, the log being supported by a substantially planar log supporting surface, the chain saw having a saw chain, saw bar, motor end and opposite nose bar end, the attachment comprising: frame means having interconnected frame members for straddling the log without contacting the log; a plurality of sliding members mounted to said frame for direct contact with said supporting surface such that said frame can slide on said supporting surface relative to said log, said sliding members having substantially planar bottom portions; mounting means for mounting the chain saw such that said saw chain defines an imaginary cutting plane disposed at a predetermined relationship to said log supporting surface; height adjusting means interconnecting said frame means and mounting means for adjusting the height of said mounting means relative to said log supporting surface; said frame means including a plurality of substantially vertical support members and horizontal support means supportively interconnecting said vertical members; said horizontal support means including opposed pairs of telescoping support members adjustable to vary the width of said frame means and thereby accommodate saw bars of different lengths; said mounting means including first clamping means for clamping said nose bar end and second clamping means for clamping said motor end; said height adjusting means including a pair of rotatable threaded elements, one associated with each said first and second clamping means, and a pair of vertically movable support elements, one connected to each said first and second clamping means, each said movable support element being threadably engaged by one said threaded element such that rotation of said threaded element causes its associated said support element and clamping means to move upwardly or downwardly; and said height adjusting means further including a drive chain cooperable with said threaded support elements for translating rotation of one said threaded element into simultaneous corresponding rotation of the other said threaded element.