Patent Application
20200008349
None.
A rotary lawnmower blade having replaceable blade components pivotally attaching to a blade base provides a user with a plurality of cutting edges and cut margins and also to provide replaceable blade components which may be bought in bulk for keeping a sharp edge available without having to replace and entire blade or sharpen a dull blade.
A preliminary review of prior art patents was conducted by the applicant which reveal prior art patents in a similar field or having similar use. However, the prior art inventions do not disclose the same or similar elements as the present replaceable cutting edge rotary lawnmower blade, nor do they present the material components in a manner contemplated or anticipated in the prior art. A disc mower blade that provides a plurality of radial teeth with a sharp presenting margin to be used on a roadside mower, with a central disc attaching numerous radial teeth for cutting grass, shown in U.S. Design Pat. D579126 and U.S. Patent Publication No. 2013/0111863 to Johnson. A dual cutting margin blade is shown in U.S. Patent Publication No. 2013/0199148 to Coudeau, Jr. An adjustable length rotary mower blade is shown in U.S. Pat. No. 5,791,131 to Hill which provides a component assembled rotary lawnmower blade, but the extending cutting margin adjusts for length, but does not provide for pivotal rotation, which deflects force and pivots away from the blade body in the event of impact with a hard object.
The present component rotary blade provides a fixed blade body attached to rotary shaft of the rotary lawnmower with pivotally attaching dual cutting margin blade components, which can be flipped to present a fresh cutting margin when the other cutting margin becomes dull, and also accepts replacement blade components to support a variety of cutting edge shapes or lawn grass accessories.
Lawnmower blades attach below the deck of a rotary lawnmower to a central shaft. These blade are most often provided as a hard piece of rectangular metal which has a sharp edge on the presenting margin of the bilaterally symmetrical blade to provide the blade with balance and cutting qualities. Over time the blades become dull and require either sharpening or replacement with sharpening capable of throwing of the balance of the blade which can damage the mower, or blade replacement which is expensive and requires the user to use tools and effort to turn the mower on its side to access the blade being replaced, which may be difficult to do if the nut holding the blade is stuck or frozen. It is also difficult to maintain the blade stationary while attempting to remove the screw.
The primary objective of the present component blade is to provide easy replacement or a dual cutting margin to either quickly refresh the cutting edge, to provide more than one blade cutting margin configuration and to easily replace each component blade by removal of a single retaining screw which provides a fresh sharp blade as often an necessary. A secondary objective is to provide the component blade in pivotal attachment to minimize damage from impact with a hard object during use, allowing the blade component to pivot away from the impact object to reduce the amount of force being delivered to the cutting margin over that of a fixed blade cutting margin striking the same hard object. A third objective is to prevent the use from having to remove the entire blade during exchange which requires more effort to stabilize the blade for removal of the central nut on the mower shaft over that required to remove the pivotal blade screws used to retain the blade component is pivotal assembly with the blade base on each end.
The following drawings are submitted with this utility patent application.
A replaceable component rotary lawnmower blade 10, shown in
The blade base 20 is a reenforced metal component having an overall rectangular shape and an overall flat profile, as seen in
The resulting full rotational engagement provides improved utility features over that of a fully integrated fixed blade in several manners. First, by providing the replaceable blade component 30 in pivotal rotation, the replaceable blade component 30 is more likely to resist deformation and dulling of the presenting cutting edge 35. Second, the replaceable blade components 30 is less likely to propel a hard object from underneath the lawnmower deck due to the pivotal rotation absorbing a portion of the momentum forces generated by a solid lawnmower blade. Third, in the event there is impact with something other than grass, the replaceable blade components 30 may spin completely away from the object after initially striking that object wherein a solid blade may strike that object numerous times. Fourth, by providing the replaceable blade component 30 attaching by the connector pin 50, if the replaceable blade component 30 is damaged, the damaged replaceable blade component may be quickly exchanged with a new one. Fifth, by providing the blade base 20 as one component and the replaceable blade components 30 as another, the blade base 20 is universally applied to any rotatory lawnmower regardless of cutting diameter.
The replaceable blade components 30 attached to the blade base 20 would be variable in length, shape and size which are suitable to the rotary lawnmower cutting diameter to which they are applied. As shown in
The connector pin 50, best illustrated in
While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that changes in form and detail may be made therein without departing from the spirit and scope of the invention.
