US-12622351-B1 - Lawn mower blade assembly with replaceable cutters

US12622351B1US 12622351 B1US12622351 B1US 12622351B1US-12622351-B1

Abstract

lawn mower blade assembly including a blade having an elongated section, and extending plates, each extending plate extending from the elongated section. Each of the extending plates includes connecting holes. The lawn mower blade assembly includes a plurality of cutters, each cutter having an interfacing section with cutter connecting holes configured to align with the connecting holes. Each cutter includes a cutter raised section extending from the interfacing section and has a cutter cutting edge. The cutters are removably attachable to the extending plates using fasteners that pass through the cutter connecting holes and the connecting holes. The blade assembly allows individual cutters to be removed and replaced without removing the entire blade assembly from the lawn mower spindle shaft.

Inventors

Wilburn B. Lancaster

Assignees

Wilburn B. Lancaster

Dates

Publication Date: 20260512
Application Date: 20250918

Claims (9)

1 . A lawn mower blade assembly, comprising: a blade comprising an elongated section with a central hole configured to receive a spindle shaft; a first slant section extending from said elongated section toward a first end; a second slant section extending from said elongated section toward a second end; a first extending plate connected to said elongated section through said first slant section and positioned at said first end; a second extending plate connected to said elongated section through said second slant section and positioned at said second end, wherein said first extending plate comprises first connecting holes and a first cutting edge, and said second extending plate comprises second connecting holes and a second cutting edge; a pair of cutters, each cutter comprising an interfacing section having cutter connecting holes configured to align with said first connecting holes or said second connecting holes, a cutter raised section extending from said interfacing section, a cutter cutting edge positioned on said cutter raised section, and a cutter slant section transitioning between said interfacing section and said elongated section; and a plurality of fasteners configured to removably secure said cutters to said first extending plate and said second extending plate through said aligned holes, wherein said cutters are positioned above said first extending plate and said second extending plate when attached.
2 . The lawn mower blade assembly of claim 1 , wherein said elongated section further comprises sectional holes positioned on both sides of said central hole.
3 . The lawn mower blade assembly of claim 1 , wherein said cutter raised section is angled relative to said interfacing section to create a three-dimensional cutting profile.
4 . The lawn mower blade assembly of claim 3 , wherein said cutter cutting edge is positioned along a leading edge of said cutter raised section relative to a direction of rotation during operation.
5 . The lawn mower blade assembly of claim 1 , wherein said cutter slant section is configured to sit above said first slant section or said second slant section when said respective cutter is attached to said first extending plate or said second extending plate.
6 . The lawn mower blade assembly of claim 1 , wherein said cutter cutting edge of each cutter is positioned to operate in coordination with said first cutting edge or said second cutting edge of said respective extending plate.
7 . The lawn mower blade assembly of claim 1 , wherein said fasteners comprise bolts and nuts.
8 . The lawn mower blade assembly of claim 1 , wherein said cutter slant section is angled between 30 to 65 degrees relative to said interfacing section.
9 . A method of providing a lawn mower blade assembly, said method comprising the steps of: providing a blade comprising an elongated section with a central hole configured to receive a spindle shaft; providing a first slant section extending from said elongated section toward a first end; providing a second slant section extending from said elongated section toward a second end; providing a first extending plate connected to said elongated section through said first slant section and positioned at said first end; providing a second extending plate connected to said elongated section through said second slant section and positioned at said second end, said first extending plate comprising first connecting holes and a first cutting edge, and said second extending plate comprising second connecting holes and a second cutting edge; providing a plurality of cutters, each cutter comprising an interfacing section having cutter connecting holes configured to align with said first connecting holes or said second connecting holes, a cutter raised section extending from said interfacing section and comprising a cutter cutting edge that is positioned on said cutter raised section, and a cutter slant section transitioning between said interfacing section and said elongated section; and removably connecting said cutters to said first extending plate and said second extending plate using fasteners that pass through said cutter connecting holes and said first and second connecting holes, such that said cutters are positioned above said first extending plate and said second extending plate when attached and said connecting holes.

Description

BACKGROUND OF THE INVENTION Field of the Invention The present disclosure relates to lawn mower blade assemblies, and more particularly to a lawn mower blade assembly with replaceable cutters that can be maintained without removing the entire blade assembly from the mower. Description of the Prior Art Lawn mowers are widely used for maintaining grass and vegetation in residential, commercial, and industrial settings. These machines typically employ rotating cutting blades mounted beneath a deck housing to trim grass to a desired height. The cutting blades are subject to regular wear and dulling through contact with grass, soil, rocks, and other debris during operation. Traditional lawn mower blade maintenance involves removing the entire blade assembly from the mower for sharpening or replacement. This process typically requires users to tilt the mower or access the underside of the deck, disconnect the blade from the spindle shaft, and transport the blade to a sharpening facility or replace it entirely. Users often find themselves lying on the ground, lifting heavy equipment, or maneuvering the mower onto ramps or other support structures to gain access to the blade assembly. The conventional approach to blade maintenance presents several challenges. Users may experience physical strain from lifting and positioning equipment, potential safety concerns from working beneath machinery, and inconvenience from the time and effort involved in blade removal and reinstallation. Additionally, when blades become dull, the entire blade assembly is often discarded and replaced, even though only the cutting edges may be worn while the remainder of the blade structure remains functional. The frequency of blade maintenance varies depending on usage conditions, but regular attention to blade sharpness contributes to optimal cutting performance and engine efficiency. Dull blades can result in poor cutting quality, increased fuel consumption, and potential damage to grass through tearing rather than clean cutting. Current maintenance practices may discourage users from maintaining optimal blade sharpness due to the associated inconvenience and physical demands. Various lawn mower configurations exist in the market, including push mowers, self-propelled units, and riding mowers with different deck sizes and blade arrangements. Some mowers utilize single blade systems while others employ multiple blades. Different blade types are available for specific cutting applications, such as standard cutting, mulching, and various lift configurations for different grass conditions. An example is disclosed in a Japanese Patent No. 5995766, entitled “Moore” (“the '766 Patent”). The '766 Patent discloses a mower capable of more simply grinding a cutter blade. The mower includes a mower deck, a cutter blade that is provided inside the mower deck and rotativity driven around a vertically-directed shaft center; an opening that is formed in the mower deck and from which a grinding tool for grinding the cutter blade is taken into the mower deck; and a lid member that can switch the opening between opened and closed states. Another example is disclosed in a U.S. Publication No. 20250107483, entitled “Type of grass trimmer and method of using the same” (“the '483 Publication”). The '483 Publication discloses a grass trimmer comprising a machine head including at least one electric motor, a grass trimmer head driven by the electric motor, and a housing for containing the electric motor. And a base including a shell. In addition, there is a trimming wheel device and a tank wheel device which assist in moving the grass trimmer head. The tank wheel device and the trimming wheel device form a detachable connection to the base. When trimming is required, the base connects to the trimming wheel device. When mowing is required, the tank wheel device replaces the connection between the trimming wheel device and the base. Although the above discussed disclosures are useful, they still have problems and present incomplete solutions. The conventional blade replacement process requires users to physically tilt the entire lawn mower to access the underside of the deck, which may involve significant physical strain and potential injury risk. Users must position themselves beneath or alongside the tilted equipment to reach the blade assembly, often requiring them to lie on the ground or assume uncomfortable positions that may contribute to back strain and other physical discomfort. The blade removal process involves disconnecting the blade and associated washers from the spindle shaft, which requires users to place their hands in proximity to the blade path area. This positioning may present safety concerns, particularly when working with sharp blade edges or when the blade assembly is not properly secured during the removal process. When installing replacement blades, users must ensure proper orientation of the cutting edges relative to the rotation direction