1. Field of Invention
This invention relates generally to the field of lawn and garden tools and, more particularly, to a fixed-line trimmer device for use in cutting vegetation.
2. Description of Related Art
Rotary string trimmers are commonly used for trimming grass and other vegetation in areas not accessible by conventional lawn mowers. These line trimmers are typically powered by either a small engine or electric motor mounted and have a rotary line trimmer head connected to a drive spindle which is rotatably mounted on the end of an elongated boom. One or more segments of 0.05 to 0.10 inch diameter cutting line extend radially outward from the line trimmer head.
During use, the cutting portion of the line becomes damaged and needs to be replaced. A number of varying mechanisms to achieve line replacement have been developed over the years. The most common technique is to include a spool of line within the head and incrementally advance the line, thereby extending the cutting line to replace the damaged portion. This type of trimmer typically has a bump head in which the line incrementally advances in response to the trimmer head being bumped on the ground. Other trimmer heads are of the automatic variety in which the line incrementally advances in response to a significant change in rotational speed of the trimmer head, i.e., reducing the engine to idle and then resuming full operational speed.
The problem associated with spool-type trimmer heads is that the line may become tangled within the spool or welded to itself during periods of extended heavy use. Therefore, there is a trend toward using trimmer heads which utilize fixed-length line segments which are simply discarded when worn and replaced with a new line segment. While this results in a smaller percentage of the line being actually used, the tangling problems are eliminated and heavier line gauges may be utilized. Heavier line gauges extend the interval of time between line replacements.
A variety of fixed line trimmer heads have been developed. Some utilize line segments which have an enlarged head formed thereon to retain the line to the trimmer head. Others use uniform cross-section segments of line that may be severed from a large spool. Uniform cross-section line enables the replacement line to be easily obtained from convenient low cost sources. Problems, however, occur in simply and securely attaching the line segment to the trimmer head while also permitting the line segment to be quickly replaced.
USPTO Backgrounds
USPTO Backgrounds