Abstract: A guide bar for a chain saw of a tree harvester adapted for applying treatment material to the stump upon severing a tree. The guide bar, typically a laminated bar includes an inner channel in the inner laminate that connects to a series of dispersal holes in the outer laminates and along the bar length. Multiple inlet holes also in the outer laminate or laminates are provided in a rear region of the bar for directing material flow into the channel. Only one of the inlet holes is in use and the other inlet holes are plugged. The invention provides for plugging unused inlet holes with a member (plug) that slides into position over the unused inlet holes at the inner side of the outer laminate. Numerous variations are proposed including both automatic, where treatment material flow generates an inner pressure that urges a member against the inner side of the unused hole and manual, where a blocking tab is manually slid into place at the inner side of the hole.

Abstract: A guide bar for a chain saw of a tree harvester adapted for applying treatment material to the stump upon severing a tree. The guide bar, typically a laminated bar includes an inner channel in the inner laminate that connects to a series of dispersal holes in the outer laminates and along the bar length. Multiple inlet holes also in the outer laminate or laminates are provided in a rear region of the bar for directing material flow into the channel. Only one of the inlet holes is in use and the other inlet holes are plugged. The invention provides for plugging unused inlet holes with a member (plug) that slides into position over the unused inlet holes at the inner side of the outer laminate. Numerous variations are proposed including both automatic, where treatment material flow generates an inner pressure that urges a member against the inner side of the unused hole and manual, where a blocking tab is manually slid into place at the inner side of the hole.

Abstract: A chain saw guide bar for a tree harvester is arranged to yield when an excessive force is applied such as when the guide bar becomes jammed in a cut. Yielding of the guide bar protects the bar holder from damage. The guide bar is heat treated or otherwise structurally modified to provide the desired yield strength.

Abstract: A chain saw guide bar including a chain tightening mechanism. A shaft or rack slidable within the bar body includes a head portion slidable rearwardly against a bar mounting stud. The head portion resides between opposed edges formed in the bar body and the head portion includes fingers that straddle the mounting stud. Rearward sliding of the shaft or rack against the stud produces a lateral force urging spreading of the fingers to produce wedging of the fingers between the opposed edges and the stud. Such wedging of the fingers produces resistance to return sliding of the shaft and retains the tightened condition of the chain.

Abstract: A guide bar mounting arrangement for a tree harvester. The tail end of the guide bar is provided with a center slot and pin receiving slot at each side thereof. A sliding block has a center boss and pins permanently or removably mounted therein at the sides of the boss and the combination is slidably mounted in a fixture or base member fixedly secured to the harvester adjacent a drive sprocket. The guide bar is fitted to the sliding block center slot receiving a center boss of the sliding block and the pin receiving slots engaging the pins of the sliding block. A saw chain is entrained around the guide bar and drive sprocket and the sliding block moved relative to the sprocket to tension the saw chain. The sliding block is forced against the base member to clamp the bar in position.