Claims
- 1. A guide bar for a chain saw wherein the guide bar is mounted on a mounting stud of the saw in a manner that permits relative linear sliding for tightening of a saw chain entrained on the bar and a drive sprocket of the saw, said chain saw guide bar comprising:
- an elongated body defining an axis along its length and having a saw chain guide edge extended around a top, a bottom and a front end of the bar, said body having a rear end to be mounted to said chain saw adjacent said drive sprocket, a mounting slot extended through the bar adjacent the rear end thereof and extended axially along the bar length and adapted to receive the mounting stud of the chain saw;
- a cavity formed in the body and axially extended forward of the mounting slot and in communication with the mounting slot, a movable shaft entrapped in the cavity and slidable axially therein and having a rear end portion extended into the mounting slot and engaging the mounting stud of the chain saw with the bar mounted to the chain saw;
- one of said cavity and slot defining opposed side edges, said rear end portion configured to have rearwardly projecting fingers each having opposed inner and outer edges, said fingers configured to straddle the mounting stud and the mounting stud engaging the inner edges of the fingers to urge spreading of the fingers when the shaft is forced against the stud, and said shaft in communication with the exterior of the bar to permit manual slidable movement of the shaft to force the rear end portion of the shaft against the mounting stud whereby the bar is moved to tighten the chain and the resistance to further tightening generating spreading of the fingers which become wedged between the stud and the opposed side edges.
- 2. A chain saw guide bar as defined in claim 1 wherein the shaft is split lengthwise from between the fingers and forwardly thereof whereby the spreading of the fingers is permitted by opening of the split.
- 3. A chain saw guide bar as defined in claim 2 wherein the side edges engaged by the fingers are tapered forwardly and inwardly whereby when in a tightened condition, forward movement of the shaft and the mounting stud relative to the bar is resisted.
- 4. A chain saw guide bar as defined in claim 3 wherein the outer edges of the fingers are configured to have a taper substantially matching the taper of the side edges when spread apart by the mounting stud.
- 5. A chain saw guide bar as defined in claim 1 wherein a second cavity is formed in the body intersecting said cavity, said second cavity configured to receive a pinion having peripheral teeth, said shaft having mated teeth along one edge and inter-engaged with the teeth of the pinion, said pinion exposed to the bar exterior for manual manipulation and turning of the pinion resulting in sliding of the shaft.
- 6. A chain saw guide bar as defined in claim 5 wherein the second cavity is configured to provide a substantially smooth wall interrupted by a notch, said pinion having free movement within the second cavity and said notch configured to engage the teeth of the pinion and provide a stop to resist turning of the pinion, said notch strategically positioned at a forward position of the second cavity whereby a rearward thrust on the bar induces positioning of the pinion forward in the cavity and engagement of the teeth of the pinion in the notch.
- 7. A chain saw guide bar as defined in claim 1 wherein the guide bar is formed of side laminates and a center laminate bonded together, said cavity provided in the center laminate and providing the opposed side edges.
- 8. A chain saw guide bar as defined in claim 7 wherein the shaft is provided with a plurality of holes along its length and the bar is provided with holes exposed to the bar exterior and in overlying non-registered relation with the holes in the shaft whereby the movement of the shaft in the bar is provided by a lever action that moves the hole positions of the shaft relative to the hole positions of the bar.
- 9. A guide bar for a chain saw wherein the guide bar is mounted to housing of the chain saw in a manner that permits relative linear sliding for tightening of a saw chain entrained on the bar and a drive sprocket of the saw followed by fixed clamping of the bar to the saw, said guide bar comprising:
- an elongated guide bar body defining an axis along its length and having a saw chain guide edge extended around a top, a bottom and a front end of the guide bar body, said guide bar body having a rear end configured to be mounted to the chain saw at a position relative to the drive sprocket;
- a movable shaft slidable axially in the bar, a slot in the bar receiving a fixed member from the chain saw that is extended through the slot and providing thereby for abutting engagement between the shaft and the chain saw whereby movement of the shaft relative to the bar produces movement of the bar relative to the drive sprocket of the chain saw for tightening the chain;
- said shaft exposed to an exterior of the bar to permit manual urging between the shaft and the bar for chain tightening, and a holding mechanism holding the shaft in the tightened position and permitting thereby the fixed clamping of the bar to the housing.
- 10. A guide bar as defined in claim 9 wherein the shaft is provided with holes and the guide bar body is provided with mating holes, said holes in the shaft alignable with holes in the bar body and mated so that with a hole of the shaft coinciding with a hole in the bar body, a second hole of the shaft is only partially overlapped with a second hole in the bar body whereby a tool will force alignment of the second holes to force the rearward movement of the shaft.
- 11. A guide bar as defined in claim 10 wherein the tool is tapered and upon the shaft having reached the tightened condition, the tool is wedged into mated holes for providing the holding mechanism.
- 12. A guide bar as defined in claim 9 wherein the member extended through the slot is a member fixed to the chain saw, and wherein the holding mechanism comprises:
- the shaft having a rearwardly facing head end and a slidable member slidable along opposing edges in the bar and between the head end and the member fixed to the chain saw, said slidable member having a front end that is V-shaped defining fingers and said head end forming a cam shape engaging said fingers whereby a rear end of the slidable member engages the fixed member and when movement is resisted, the interaction of the fingers and the head end produces wedging of the fingers against opposing side edges of the slot.
Parent Case Info
This is a continuation-in-part of U.S. Ser. No. 08/944,933 pending filed Oct. 2, 1997.
US Referenced Citations (27)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1329966 A1 |
Mar 1985 |
RUX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
944933 |
Oct 1997 |
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