Patent Application
20100064529
This invention relates to tools, and more particularly to anvil type pruners and loppers with shock absorbing features.
Anvil type pruners and loppers, where a cutting blade is moved down against an anvil portion with a branch being cut therebetween, are highly effective.
However, the impact of the blade to the anvil, especially when cutting hard or thick branches or the like, can result in a jarring physical shock, which is transmitted to the user's hands and arms. Such physical shock can lead to user fatigue or increase the likelihood of repetitive motion injuries and carpal tunnel syndrome.
In accordance with the invention, an anvil type pruner/lopper is provided with a shock absorbing feature to dampen the physical shock between the blade and anvil when completing a cut.
Accordingly, it is an object of the present invention to provide an improved anvil pruner/lopper which promotes clean cuts.
It is a further object of the present invention to provide an improved anvil pruner/lopper with shock absorbing features built in along with promoting clean cuts.
It is yet another object of the present invention to provide an improved anvil pruner/lopper with a shock absorber provided to the anvil portion for reduction of physical shock from cutting operations.
The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements.
The system according to a preferred embodiment of the present invention comprises an anvil pruner/lopper having a shock absorbing feature.
Referring to
Referring now to
The anvil portion has an interior region that receives anvil cutting base and shock absorbing member 28 therein. In the illustrated embodiment, anvil portion 14 has a central opening slot 15 of a first width, with an interior region 17 of greater width. A stepped profile is provided by an upper ledge 34 of the anvil portion 14 and anvil cutting base 26 has a corresponding profile portion 32 to interact therewith to define an upper extension limit to the cutting base relative to the interior profile. In the illustrated embodiment, the profiles are of substantially right angle edges, but other profiles may be employed, whether with sharply defined edges or smooth or curved edges.
Referring now to
Referring to
Anvil cutting base 26 and shock absorbing member 28 suitably insert into the space define in anvil portion 14, in the direction of arrow 40, and are secured therein against unintended removal by key 38 which is inserted into a corresponding key slot 44 in anvil portion 14, to block removal thereof.
Thus, assembly is accomplished by inserting cutting base 26 and shock absorbing member 28 into the opening of anvil portion 14, followed by insertion of key 38. By reverse procedure, the cutting base and shock absorbing members can be removed for repair or replacement.
In a particular embodiment, blade portion 12 is made of steel, anvil portion 14 is of aluminum, pivot 16 comprises a center oiler bolt and handles 18, 20 comprises aluminum handle members. Bolts 22, 24 are hardened bolts or other suitable fasteners that create a compound action in conjunction with the configuration and shape of the other portions of the device to enable reduction in the amount of strength required to complete a cut. The pivot 16 may comprise, for example, a center oiler bolt by Barnel International, Inc., Portland, Oreg. US, which includes an interior lubrication reservoir with lubrication channels to provide ongoing lubrication to the pivoting region and elements during use. The reservoir includes a refilling capability to replenish the lubrication as desired. Anvil cutting base 26 comprises nylon fiberglass and shock absorbing member 28 comprises poly urethane rubber material. The cutting base 26 may also be a metal member, or of other composition to provide an engagement surface to meet with the blade. Alternatively, shock absorbing member may be a leaf spring or other mechanical spring mechanism. Key 38 (which is optional) and may comprise nylon fiberglass, is sized to provide a friction fit to remain in place in absence of intentional removal forces being applied thereto.
Referring to
With the above embodiments, the shock absorber 28 and base 26 can suitably be replaced as desired, to accommodate wear. A complete replacement anvil with base 26 and shock absorber 28 installed therein may be provided as replacement parts.
Accordingly, in accordance with the above description, an anvil type pruner/lopper is provided having shock absorbing capabilities, to provide a more comfortable cutting action, reduced operator fatigue and the like. The operation of the shock absorbing features results in less physical shock being transmitted through the handles of the pruner/lopper to the user's hands. Also, the compound action design of the anvil base tang provides desirable operational results.
The device promotes clean cuts, leaving no bark strings, etc., as a result of the liner 26 that operates as a cushioning device, as well as to promote ergonomic cuts. Use of the liner 26 also is less apt to dull the blade edge as compared with conventional anvil type cutting devices, but instead retains the longevity of the cutting edge. The blade edge remains ultra sharp given that it is not coming in contact with aluminum but instead with the liner which promotes clean cuts yet remains friendly with the blade coming in contact with it.
While plural embodiments of the present invention has been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fall within the true spirit and scope of the invention.
