Adjustable debris shield for a hand-held power trimmer

Harvesters – Motorized harvester – Including cutter yieldably mounted on its drive means

Reexamination Certificate

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Details

C030S276000

Reexamination Certificate

active

06779324

ABSTRACT:

BACKGROUND OF THE INVENTION
Existing hand-held power trimmers can be configured as a string trimmer or as a brushcutter. It is believed that string trimmers can be used to cut leafy vegetation such as grass and weeds and that brushcutters can be used to cut heavier vegetation with thicker stems such as tall grasses, shrubs and sapling trees. The cutting element of these power tools can be driven by either an electric motor or an internal combustion engine.
Certain ones of these hand-held power tools can be converted between a brushcutter and a string trimmer by exchanging the cutting element between a rotary blade and a cutting line assembly. It is believed that the debris shield of a string trimmer is of a different size as compared to that for a brushcutter. In order to accommodate these two different types of cutting elements, it is believed that two distinctly sized shields are used and that the brushcutter shield extends a larger angular span about the rotation axis than does the shield for a string trimmer.
It is believed that a convertible hand-held power trimmer provided with a single shield will unduly restrict visibility when the power trimmer is configured as a string trimmer so that this dual purpose shield is sufficient for use with the rotary blade. It is believed that this oversized dual-purpose shield will span an unnecessarily large portion of the path of the cutting line, thus, possibly restricting the operator's visibility of the cutting circle and, in turn, possibly limiting the precision with which the vegetation can be trimmed such that unwanted cutting of the surrounding vegetation or other objects can occur.
SUMMARY OF THE INVENTION
The present invention provides a hand-held power tool including a debris shield adjustable between a first mode and second mode where the debris shield is initially configured in the first mode.
The present invention also provides a hand-held power tool including an elongate shaft, a mounting structure disposed on one end of the elongate shaft, a cutting element, a prime mover, and an adjustable debris shield. The mounting structure has a rotation axis at an angle relative to the longitudinal axis of the elongate shaft. The cutting element is mounted to the mounting structure and includes at least one of a cutting line assembly and a rotary blade. The prime mover drives the mounting assembly to rotate the cutting element about the rotation axis. The adjustable debris shield has a first operative mode and a second operative mode. The adjustable debris shield has a first lateral span relative to the longitudinal axis when in the first operative mode and a second lateral span relative to the longitudinal axis when in the second operative mode. The second lateral span is greater than the first lateral span.
The present invention yet also provides a hand-held power tool including an elongate shaft, a mounting structure disposed on one end of the elongate shaft, a cutting element, a prime mover, and an adjustable debris shield. The mounting structure has a rotation axis at an angle relative to the longitudinal axis of the elongate shaft. The cutting element is mounted to the mounting structure and includes at least one of a cutting line assembly and a rotary blade. The prime mover drives the mounting assembly to rotate the cutting element about the rotation axis. The adjustable debris shield has a first operative mode and a second operative mode. The adjustable debris shield includes a stationary wall and an extension wall. The stationary wall is secured to one of the mounting structure and the elongate shaft and extends toward the second end of the elongate shaft. The extension wall is coupled laterally adjacent to the stationary wall.
The present invention further provides a hand-held power tool including an elongate shaft, a mounting structure coupled to one end of the elongate shaft, a cutting element, a prime mover, and an adjustable debris shield. The mounting structure has a rotation axis at an angle relative to the longitudinal axis of the elongate shaft. The cutting element is mounted to the mounting structure and includes at least one of a cutting line assembly and a rotary blade. The prime mover drives the mounting assembly to rotate the cutting element about the rotation axis. The adjustable debris shield has a first operative mode and a second operative mode. The adjustable debris shield includes a stationary wall and an extension wall. The stationary wall is secured to one of the mounting structure and the elongate shaft and extends toward the second end of the elongate shaft. The extension wall is secured to the stationary wall and movable relative to the stationary wall between a first retracted position where the stationary wall substantially overlaps the extension wall and an extended position where the extension wall extends laterally from the stationary wall relative to the longitudinal axis.
The present invention provides a hand-held power tool including a debris shield adjustable between a string trimmer shield and a brushcutter shield where the debris shield is initially configured as a string trimmer shield.
The present invention further provides a hand-held power tool convertible between a string trimmer and a brushcutter including an elongate shaft, a mounting structure coupled to the first end of the elongate shaft having a rotation axis angled relative to the elongate shaft, a prime mover coupled to the mounting structure, a cutting element removably mounted to the mounting structure and a shield secured to one of the mounting structure and the elongate shaft. The cutting element rotates in a cutting plane perpendicular to the rotation axis. The shield includes a primary wall extending toward the second end of the elongate shaft and terminating in a rear edge. The rear edge is located at a position at least co-planar with the cutting plane. The shield has an angular span of less than 90 degrees about the rotation axis.
The present further provides a method for converting a hand-held power tool between a string trimmer and a brushcutter. The power tool includes an adjustable shield having a rotation axis, a longitudinal axis, a first operative mode, a second operative mode, a first lateral span in the first operative mode, and a second lateral span in the second operative mode. The second lateral span is greater than the first lateral span. The method includes attaching a cutting line assembly to the hand-held power tool. Next, the adjustable shield is placed in the first operative mode when the cutting line assembly is attached to the hand-held power tool. Then, the cutting line assembly is replaced with a rotary blade. The adjustable shield is then placed in the second operative mode when the cutting line assembly is replaced with the rotary blade.


REFERENCES:
patent: 3797213 (1974-03-01), Sadow, Jr. et al.
patent: 4049059 (1977-09-01), Weibling
patent: 4364435 (1982-12-01), Tuggle et al.
patent: 4679385 (1987-07-01), Carmine
patent: 4736573 (1988-04-01), Seck
patent: 4756148 (1988-07-01), Gander et al.
patent: 4803831 (1989-02-01), Carmine
patent: 4864728 (1989-09-01), Kloft et al.
patent: 5010720 (1991-04-01), Corsi
patent: 5279100 (1994-01-01), Pruitt et al.
patent: 5385005 (1995-01-01), Ash
patent: 5423126 (1995-06-01), Byrne
patent: 5490371 (1996-02-01), Potucek, III
patent: 5768786 (1998-06-01), Kane et al.
patent: 5940973 (1999-08-01), Kitz
patent: 5996234 (1999-12-01), Fowler et al.
patent: 6052976 (2000-04-01), Cellini et al.
patent: 6116349 (2000-09-01), Wilson
patent: 6327782 (2001-12-01), Blevins

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