Patent ID: 12251848

Corresponding reference characters indicate corresponding parts throughout the several views of the figures. The figures represent an illustration of some of the embodiments of the present invention and are not to be construed as limiting the scope of the invention in any manner. Further, the figures are not necessarily to scale, some features may be exaggerated to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Also, use of “a” or “an” are employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

Certain exemplary embodiments of the present invention are described herein and are illustrated in the accompanying figures. The embodiments described are only for purposes of illustrating the present invention and should not be interpreted as limiting the scope of the invention. Other embodiments of the invention, and certain modifications, combinations and improvements of the described embodiments, will occur to those skilled in the art and all such alternate embodiments, combinations, modifications, improvements are within the scope of the present invention.

As shown inFIG.1, an exemplary self-propelled cutter10is in an upright position and has a drive assembly14including a drive gear40engaged with a transfer gear50and the transfer engaged with a propulsion gear60by a lever arm70. The lever arm70enables the propulsion gear60to rotate about the transfer gear50as required to drive the material through the cutter10. As indicated by the bold arrows, the propulsion gear60is driven indirectly by the drive gear40, which is driven by the drive input extension32that extends through the cutter body20. The propulsion gear60provides downward and horizontal forces on the material17to be cut. The rotational axis61of the propulsion gear60and lever arm axis71are configured at an offset angle77from the vertical axis21, extending though the rotation axis51of the transfer gear50. This offset angle and ability to pivot about the transfer gear50enables the propulsion gear60to self-regulate downward and horizontal forces on a material moving through the cutter10. The engagement teeth of the propulsion gear60may grip the material to be cut and pull it through the cutter10. The propulsion gear may have a tread68that extends around the engaging propulsion gear60, wherein the tread extends radially outward beyond engagement teeth of the propulsion gear60. The tread may provide better grip on the material to be cut17and may prevent debris from getting into the propulsion gear60. An exemplary blade80is detachably attached to the cutter body20by a blade fastener84, such as a bolt. The blade assembly82may then be removed and the blade may be exchanged for a new blade. A foot90is configured to extend under the material to be cut17and direct it over the fixed blade80.

As shown inFIG.2, an exemplary self-propelled cutter10is shown. The drive input30is shown on the first side28of the cutter body20. A first set of gears, or gear assembly15, is shown on the second side29of the cutter body20. The rotational axis41of the drive gear40and the rotational axis51of the transfer gear50are shown. The drive input extension32extends from the drive input30, through the cutter body20to the second side29of the cutter body20. The rotational axis61of the propulsion gear60will move in an arc about the rotation axis51of the transfer gear50, due to the lever arm70linkage. The lever arm70holds the transfer gear50and propulsion gear60in engagement with each other. The foot90extending in front of the fixed blade80is more clearly seen in this view. The propulsion gear60can rotate between the front-stop23and back-stop.

Referring now toFIGS.3and4, an exemplary self-propelled cutter10has a drive input30comprising a drive input extension32extending from the first side28to the second side29to drive the drive gear40; shown attached to the drive input extension inFIG.4. The transfer gear50is coupled with a transfer gear bearing54that is coupled to the cutter body20via a transfer gear mount aperture52. As shown inFIG.4, the cutter body20may have a propulsion gear body recess65to allow a propulsion gear extension to extend across or through the cutter body20to couple with a second tread. Note that the back end of this recess65provides the back-stop26to prevent the propulsion gear60from rotating too far back about the transfer gear. The cutter body20has a length from the front22to the back24and a height from the bottom27to the top25. As shown inFIG.3, the drive input is configured on a side that may be conducive for a left handed person to manipulate a hand operated input, such as a handle.

As shown inFIG.5, an exemplary self-propelled cutter10has a drive input device31, such as a crank34, to provide a drive to the drive input30. The crank is coupled with the drive input and a handle35enables manually driving the gear assembly on the second side29of the cutter body20. A cover12is coupled to the cutter body20and extends over the gear assembly for safety.

As shown inFIG.6, an exemplary self-propelled cutter10has a drive input device31, such as a crank34, to provide a drive to the drive input30. The crank is coupled with the drive input and a handle35, a t-handle36, that enables manually driving the gear assembly on the second side29of the cutter body20. A cover12is coupled to the cutter body20and extends over the gear assembly for safety.

Referring now toFIGS.7and8, an exemplary self-propelled cutter10has a gear assembly on both the first side28and second side29of the housing body20. A single drive input30drives both the first and second drive gears40,40′, respectively. The second drive gear40′ is driven by the drive input extension32that extends from the first side28to the second side29of the cutter body20. The dual sided gear assemblies14,14′, provide two propulsion gears60,60′ and two treads that may provide for more even and straight propulsion of the cutter10with respect to a material. The treads68,68′ are configured on opposing sides of the fixed blade80and rotate down to pinch material against the foot90having a width96.

As shown inFIG.9an exemplary self-propelled cutter10has a drive assembly14that utilizes a single gear assembly15on a first side28of the cutter body20. A propulsion gear60is configured on a first side28of the cutter body20and a propulsion gear extension64extends from the first side28of the cutter body20to the second side29of the cutter body20through the propulsion gear body recess65. The propulsion gear extension64couples with a second tread68′ on the second side of the cutter body20. This arrangement enables the first set of gears and the lever arm70to move both the first and second treads68,68′ about the transfer gear50as required. The width96of the foot90is shown inFIG.9.

As shown inFIG.10, an exemplary self-propelled cutter10has two propulsion gears60,60′ configured on opposing sides of the fixed blade80. The propulsion gears60,60′ rotate about the transfer gear. As described herein, the self-propelled cutter may track more easily in a straight line with treads on either side of the fixed blade80.

As shown inFIG.11an exemplary self-propelled cutter10has a tread68with propulsion teeth69that is coupled with the propulsion gear60. The propulsion teeth69extend out radially from the rotational axis61of the propulsion gear a greater distance than the first propulsion engagement teeth67. The propulsion teeth69resemble saw tooth blades having individual portions and having an extended end or point and curved, straight, or radiused sides.

As shown inFIG.12, an exemplary self-propelled cutter10has a worm gear46that engages with the transfer gear50. The drive input30extends to the back24of the cutter10or cutter body20. A drive input device can be easily coupled with the drive input30to propel the cutter forward. A drive input device31, such as an electric motor37may be coupled with the drive input30to turn the drive input extension32, that has a rotational axis41that is orthogonal to the rotational axis51of the transfer gear50, or extends along the length of the cutter body20. The electric motor may have an input interface38such as a socket having planar surfaces to couple with or mate with the planar surfaces on the drive input30. The electric motor may spin the mating socket to turn the drive input and gear assembly of the cutter10. The electric motor may have an on/off button39to control the movement of the cutter10over a material to be cut.

Referring now toFIGS.13to20, an exemplary self-propelled cutter10is configured with a drive assembly14that couples with a handle35and drive input30. The handle is rotated to rotate the drive input30and the first drive gear40is attached to the drive input. The first drive gear40engages with the first transfer gear50, both on the first side28, or drive side of the self-propelled cutter body10. A transfer gear extension55extends as an axle from the first transfer gear50to a second transfer gear56, configured on a second side29of the self-propelled cutter body20, or second side of the fixed blade80. The second transfer gear56engages with a first propulsion gear60that drives a propulsion gear extension64, or axle that drives both the first tread68, coupled to the first propulsion gear and a second tread66, configured on a first side28of the cutter body20. The drive assembly is configured with two lever arms70′,70on the drive or first side28and on the second side29, respectively. Lever arm70extends on the second side29from the propulsion gear axle, or propulsion gear extension64, to the transfer gear extension55. The lever arm70′ extends on the first side from the propulsion gear extension64to the transfer gear extension55, therefore the two lever arms70,70′ move in unison to keep the two treads engaged with the material to be cut.

As shown inFIG.14, the fixed blade80is configured between the first tread68and the second tread66.

As shown inFIG.17, the exemplary drive assembly14is in a down and drive configuration and the handle35is being turned to pivot the lever arm70as indicated by the bold curved arrow. The lever arm70is pivoted down to engage a material being fed over the foot and into the cutter10. As shown inFIG.18, the tread68is up from the foot90and the lever arm70is pivoted up.

FIG.19shows the self-propelled cutter10shown inFIGS.13-18and20-21with the cover12configured thereon.

Referring now toFIGS.20and21, an exemplary drive assembly14comprises a first transfer gear50that is on a first side, or drive input side, of the cutter body, (not shown), a transfer gear extension55that extends to a second transfer gear56, on a second side of the cutter body. The second transfer gear56engages with the first propulsion gear60through the gear teeth57of the second transfer gear56engaging with the engagement teeth67of the first propulsion gear. A tread68is coupled with the first propulsion gear and has propulsion teeth that extend radially out beyond the engagement teeth67of the first propulsion gear. The lever arm70is coupled between the first propulsion gear and the second transfer gear56, and holds these two gears in engagement. The lever arm70pivots around the transfer gear extension55, or rotation axis51of the second transfer gear56, and the propulsion gear extension64, or rotational axis of the propulsion gear61. A spring receiver recess85is shown in the lever arm70inFIG.20, and a spring86is configured in the spring recess inFIG.21. The spring extends from the spring recess to an extended end87of the spring that is configured to interface with the housing or cover to provide a spring force on the lever arm70and to act as a back-stop26for the lever arm70, thereby preventing the lever arm70from rotating up about the propulsion transfer gear rotation axis51.

Referring now toFIGS.22to29, an exemplary self-propelled cutter is configured with a drive input device31, such as an electric motor37, that is powered to automatically drive the drive input30which then turns the gear assembly15and ultimately the two propulsion gears60,60′. The drive input30, such as the electric motor37, may be configured in a drive housing33which may extend orthogonally from the length of the cutter body20, or orthogonal to the direction of cutting101. A first gear assembly58is configured on a first side28of the cutter body and a second gear assembly59is configured on a second side29of the cutter body. As shown inFIGS.22and23, the drive input extension32extends from the drive input device31, an electric motor37and has a drive gear40coupled to the drive input extension32. The drive gear40meshes with an interface transfer gear53on the first side28of the cutter body20. The interface transfer gear53has a transfer gear extension55that extends along the rotational axis51of the interface transfer gear53. A first transfer gear50on the first side28of the cutter body20and a second transfer gear56on the second side29of the cutter body20are coupled to the transfer gear extension55, a transfer gear axle511, and are rotated about the transfer gear rotational axis51, by the attachment to the transfer gear extension55. The first transfer gear50on the first side28of the cutter body20meshes with a first propulsion gear60to turn the first propulsion teeth69, or tread68and the second transfer gear56on the second side29of the cutter body20meshes with the second propulsion gear60′ to turn the second propulsion teeth69′, or tread68′. The first and second propulsion gears and the respective propulsion gear teeth may be coupled together by a propulsion gear extension64that extends through the cutter body20along the rotational axis61of the propulsion gears to form a propulsion axle611. The gear size and ratio of the first and second transfer gears and propulsion gears may be the same to effectively drive the first and second propulsion teeth at the same speed.

As shown inFIGS.24and25, the foot90may be coupled to a foot pivot plate97that is configured to pivot about a foot pivot98to keep the foot rotated up toward the cutter body20. The foot pivot98is configured forward, or more proximal to the front22of the cutter body than the foot90and the spring99is configured back from the foot90or more proximal to the back24of the cutter body. The foot may be pivoted away from the cutter body to accommodate thicker material being fed over the foot and cut by the fixed blade80. The foot plate97pivots about the foot pivot axis91, shown inFIG.23. The spring99is coupled to the cutter body by a foot-spring body attachment93and to the foot90by a foot-spring plate attachment95, such as a post extending from the foot pivot plate9.

Referring now toFIGS.26to29, an exemplary self-propelled cutter10has an input drive device31that is coupled to the cutter body20and configured to automatically drive the gear assembly and the propulsion teeth69,69′ to pull material over the foot90and across the blade fixed80to cut the material. The drive input device is an electric motor37configured in a drive housing33that extends orthogonally to the direction of cutting or the length of the cutter body20extending from the front to the back of the cutter body. The exemplary self-propelled cutter10has a handle110and an activator button120that activates the input drive device31when activated. An additional handle140is provided to enable applying additional force as material is cut using the propelled cutter10. The combination of the dual sided tread configured on opposing sides of the cutter body20and the foot spring99pulling the foot90up toward the cutter body provides effective force between the foot and the blade to ensure the material is cut while the tread68effectively translates the material over the foot90and fixed blade80, as indicated by the two bold arrows proximal the trailing end94of the foot90inFIG.24.

As shown inFIG.28, a directional switch125is configured on the handle110to allow a user to change the direction of rotation of the propulsion teeth.

It will be apparent to those skilled in the art that various modifications, combinations and variations can be made in the present invention without departing from the scope of the invention. Specific embodiments, features and elements described herein may be modified, and/or combined in any suitable manner. Thus, it is intended that the present invention cover the modifications, combinations and variations of this invention provided they come within the scope of the appended claims and their equivalents.