A chainsaw is a power tool that may be used to cut quickly through tree trunks, branches and so on. A chainsaw may be gas or electric. One of the most inconvenient problems with a chainsaw is that during the cutting operation the chain may expand due to the heat generated by the friction between the chain and the chain guide bar. The chain may therefore increase in overall length therein causing a loss of the preset tension of the chain. When this occurs, the chain may fall off from the chain guide bar. This may cause a lot of accidents, and may take a lot time to repair.
The present device will eliminate these inconveniences, making the chainsaw operation safer, the cutting operation much smoother, and may save time by reducing required maintenance of the chainsaw. Further, the present device may not require any additional tools to operate.
An automatic chainsaw chain tension adjuster is provided. The automatic chainsaw chain tension adjuster maintains the chain of a chainsaw on the chainsaw guide bar during use of the chainsaw. As heat expands the overall length of the chain while the chainsaw is running, an internal spring forces a sprocket located at the second end of the guide bar outward therein increasing the overall path the chain must travel around the guide bar/sprocket to compensate for the heat expansion of the chain. As the chain of the chainsaw heats up or cools down during use and non-use, the internal spring automatically adjusts the chain to the exact proper tension so that the chain does not fall off the guide bar.
The present device keeps the chainsaw chain cutting at the same preset tension during the entire operation of the chainsaw. Further, the present device also meets the common “snap test” for chainsaws. The constant proper tension the present device applies to the chain is achieved by the automatic adjustment of distance between the sprocket and the guide bar of the chainsaw through an internal spring assembly. The internal spring assembly increases or decreases the distance the chain must travel to compensate for the change of the length of the chain due to heat dilatation.
The present automatic chain tension adjuster device may be used in connection with many different chainsaw designs and may be used with both gas and electric chainsaws.
Prior patents fail to describe an automatic chainsaw tension adjuster which is easy to use. Further, these patents fail to provide for an automatic chainsaw tension adjuster which allows for safe and uninterrupted use of a chainsaw.
The present automatic chainsaw chain tension adjuster continuously adjusts the distance between the driving sprocket and the fixed chainsaw guide bar. The distance between those two elements is controlled by an internal spring drive mechanism device which compensates for the increased length of the chain due to heat dilation. As a result, the chain remains on the guide bar during use.
An automatic chainsaw chain tension adjuster is provided. The automatic chainsaw chain tension adjuster maintains the chain of a chainsaw on the chainsaw guide bar during use of the chainsaw. As heat expands the overall length of the chain while the chainsaw is running, an internal spring forces a sprocket located at the second end of the guide bar outward therein increasing the overall path the chain must travel around the guide bar/sprocket to compensate for the heat expansion of the chain. As the chain of the chainsaw heats up or cools down during use and non-use, the internal spring automatically adjusts the chain to the exact proper tension so that the chain does not fall off the guide bar.
An automatic chainsaw tension adjuster is provided. The automatic chainsaw tension adjuster has an internal spring connected to the sprocket which automatically adjusts the tension on a chainsaw chain to exactly compensate for the chains dilation and therefore loosening which is caused by the increased heat created during use of the chainsaw. The internal spring moves the sprocket of the housing of the chainsaw away from the guide bar of the chain (in one embodiment) to increases the tension of the chain which would be otherwise relaxed from the expansion of the chain caused by the frictional heat created during operation. As a result, the chain remains consistently tight and is prevented from becoming disengaged with the guide bar.
One of the biggest problems with using a chainsaw is that during use the chain quickly becomes slightly longer as a result of dilation created from the heat generated by the movement of the chain. The increased length of the chain means that the chain often becomes dislocated from the guide bar of the chainsaw and needs to be properly reattached. This can result in a safety hazard. The present device solves that problem.
By the present device, the tension of the cutting chain is adjusted so that it neither binds on nor becomes loose from the guide bar during use. In order for a chainsaw to safely and effectively cut, the chain needs to have the proper tension around the metal guide bar upon which it rides. If the chain is too tight, not only will it rob the chainsaw's engine of power due to increased friction, but the chain also runs the risk of breaking. If the chain is too loose, it can come off the guide bar and seriously injure the operator. Further, if the chain is loosened the chain may cause damage to the guide bar or other portions of the chainsaw. Replacing and mounting of the chain is very difficult, requiring technical skill and requiring specialized tools. The present device maintains a consistent tension on the chain of the chainsaw while the chainsaw is in use.
An advantage of the present automatic chainsaw tension adjuster is that the present automatic chainsaw tension adjuster saves time by not requiring someone to reattach a chain to the guide bar of the chainsaw which may be caused by the chain falling off the guide bar of the chainsaw from expansion of the length of the chain during use.
And another advantage of the present automatic chainsaw tension adjuster is that the present automatic chainsaw tension adjuster has an internal spring which provides consistent tension on the chain of the chainsaw during use during heating up and cooling down of the chainsaw.
Still another advantage of the present automatic chainsaw tension adjuster is that the present automatic chainsaw tension adjuster has an internal spring mechanism which acts as a shock absorber to absorb vibrational forces that the chain of the chainsaw encounters during use, therein making the chainsaw operate more smoothly.
Yet another advantage of the present automatic chainsaw tension adjuster is that the present automatic chainsaw tension adjuster may be used in connection with gas or electric chainsaws.
And yet another advantage of the present automatic chainsaw tension adjuster is that the present automatic chainsaw tension adjuster extends the life of the guide bar and chainsaw by reducing the wear and tear of the chain guide bar which is caused by extended vibration of the chain over time.
Still another advantage of the present automatic chainsaw saw tension adjuster is that a user never needs to remove the chain bar from the chainsaw for maintenance.
Still another advantage of the present automatic chainsaw saw tension adjuster is that the chain guide bar is permanently bolted in the body of chainsaw.
Still another advantage of the present automatic chainsaw saw tension adjuster is that because the chain guide bar is permanently bolted to the body of chainsaw, the chain guide bar never becomes loosed during cutting operation.
Yet another advantage of the present automatic chainsaw saw tension adjuster is that the present device increases the safety operation of the chainsaw by eliminating accidents that typically are caused by the chain falling off of standard chainsaws.
Still another advantage of the present automatic chainsaw saw tension adjuster is that a user does not need tools to remove and replace the chain from the chainsaw for maintenance.
Another advantage of the present automatic chainsaw saw tension adjuster is that a user never needs to remove the chain bar from the chainsaw for maintenance.
For a more complete understanding of the above listed features and advantages of the automatic chainsaw tension adjuster reference should be made to the detailed description and the drawings. Further, additional features and advantages of the invention are described in, and will be apparent from, the detailed description of the preferred embodiments.
An automatic chainsaw chain tension adjuster is provided. The automatic chainsaw chain tension adjuster maintains the chain of a chainsaw on the chainsaw guide bar during use of the chainsaw. As heat expands the overall length of the chain while the chainsaw is running, an internal spring forces a sprocket located at the second end of the guide bar outward therein increasing the overall path the chain must travel around the guide bar/sprocket to compensate for the heat expansion of the chain. As the chain of the chainsaw heats up or cools down during use and non-use, the internal spring automatically adjusts the chain to the exact proper tension so that the chain does not fall off the guide bar.
An automatic chainsaw tension adjuster is provided. The automatic chainsaw tension adjuster has an internal spring connected to the sprocket which automatically increases the tension on a chainsaw chain to exactly compensate for the chains dilation and therefore loosening which is caused by the increased heat created during use of the chainsaw. The internal spring pulls the sprocket of the housing of the chainsaw away from the guide bar of the chain to increases the tension of the chain which would be otherwise relaxed from the expansion of the chain caused by the frictional heat created during operation. As a result, the chain remains consistently tight and is prevented from becoming disengaged with the guide bar.
Referring now to the figures, in an embodiment a chainsaw 1 is provided. The chainsaw 1 may have a main housing 10. The main housing 10 may have an internal motor (not illustrated) which is mechanically secured to a movable sprocket 12 which rotates three hundred and sixty degrees around a pin 13. A guide bar 20 having a first end 21 and a second end 22 may be connected to the housing 10 may act as a rail for a cutting chain 30. The first end 21 of the guide bar 20 may be rounded (such as semi-circular) while the second end 22 of the guide bar 20 may have a concave arch 23. The guide bar 20 may have a slight internal groove at its permitter wherein groove receives a portion of the chain 30 and keeps the chain 30 aligned on the guide bar 20. In an embodiment, the first end 21 of the guide bar is convex and the second end 22 is concave. In an embodiment, the arch of the concave and convex sides are substantially the same. In one embodiment, the guide bar 20 is bolted permanently to the main housing 10 of the chainsaw 1 and, therefore, never becomes loosened during use of the chainsaw 1.
The movable sprocket 12 may be located at or near the second end 22 of the guide bar 20. The movable sprocket 12 may have a plurality of teeth 14 which rotate around the circular pin 13. An adjustable space 15 may be located between the arch 23 of the second end 22 of the guide bar 20 and (an internal second base 70) of the sprocket 12. The chain 30 is forced to rotate around both the teeth 14 of the sprocket 12 and the top, the bottom and first end 21 of the guide bar 20 as a result of the motor quickly rotating the sprocket 12. The rotation of the chain 30 therein is used for cutting an object.
Referring now to
The second end 52 of the internal spring 50 is secured to (or, with the lever 100 embodiment of
Because the distance 15 between the sprocket 12 (or internal second base 70) and the stationary first end 21 of the guide bar 20 is altered by the movement of the second base unit 70 (and therein sprocket 12), the distance any specific individual link 80 of the chain 30 must travel is altered by the movement of the sprocket 12 forward or backward with respect to the first end 21 of the guide bar 20. More specifically, as the sprocket 12 moves closer to the arch 23 of the second end 22 of the guide bar 20, the full perimeter the chain 30 travels in completion of a full cycle is reduced. Conversely, as the distance 15 between the sprocket 12 and the arch 23 of the stationary second end 23 of the guide bar 20 is increased, the total distance the chain 30 travels in one full rotation is increased. Because the distance 15 between the sprocket 12 and the guide bar 20 is continuously adjusted by the internal spring 50 of the housing, the spring 50 may therein compensate for the dilation of the chain 30 from the frictional heat created during use of the chainsaw 1. As a result, a present tension on the chain 30 of the chainsaw 1 may be maintained during use.
The present internal spring 50 is biased to automatically apply pressure to force the sprocket 12 away from the arch 23 of the second end 22 of the guide bar 20 so that any slack in the chain 30 caused by the frictional heat expansion during use is automatically and precisely eliminated by the spring 50.
While using a chainsaw, the frictional heat generated by the rotating chain causes the chain to expand. In standard chainsaws, the expanded length of the chain during use, combined with the non-expanded total perimeter of the guide bar, often causes the chain to become dislocated from the guide bar causing injury to the person, damage to the property or, at the least, a delay in operation of the chainsaw.
When the chain 30 is rotating at a reduce speed or even not rotating at all, the overall length of the chain 30 is decreased. Because the internal spring 50 is constantly applying the precise counter-force to either push (as in
During use, frictional heat causes the rotating the chain 30 to dilate and therefore increase in overall length. The overall length means that the chain 30 can more easily fall off the guide bar 20. Having the internal spring 50 actively and automatically move the sprocket 12 either toward or away from the guide bar 20 results in an automatic and precise increase in tension to equal that increased length of the chain 30. Therefore, as the overall length any link 80 of the chain 30 must travel increases during use, at the same time, the spring 50 adjusts the sprocket 12 with respect to the guide bar 20 therein increasing the tension and exactly compensating of the increased length of the chain 30.
In one embodiment, the chainsaw 1 may be an automatic quick release lever 100 (
As shown in
Another advantage of the present chainsaw is that because the sprocket 12 may be moved by the lever 100 closer to the guide bar 20, a user may release the tension on the chainsaw chain to easily replace the chain without the need for any additional tools. In particular, a user first moves the lever 100 to the relaxed position (
Finally, another advantage of the internal spring 50 of the present chainsaw 1 is that the spring 50 also acts as a shock absorber by helping to absorb the friction and repetitive movement and shaking of the chainsaw 1 while the chainsaw 1 is cutting an object.
The present invention may be applied to many variances and types of chainsaws.
Although embodiments of the invention are shown and described therein, it should be understood that various changes and modifications to the presently preferred embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the invention and without diminishing its attendant advantages.
The following application is a based on and claims the priority benefit of U.S. provisional application Ser. No. 63/147,598 filed on Feb. 9, 2021 and 63/148,107 filed on Feb. 10, 2021, both currently co-pending; the entire content of which is incorporated by reference.
Number | Date | Country | |
---|---|---|---|
63147598 | Feb 2021 | US | |
63148107 | Feb 2021 | US |