Abstract: An improved blade for a rotary lawn mower includes cutting elements which are removably attached to a base member. The removable elements may be made of a higher quality steel than the base member and may be easily removed for sharpening or merely replaced with a new element. A removable element is held in the base member by means of a wedged slot which cooperates with a wedged part of the shank of the removable cutting element, while a notch in the base member serves to hold the back of the blade.

Abstract: A rotary lawn mower (2) has a rigid cutting blade (6) rotatable in a housing (4). A filament holder (12) is releasably attached to blade (6) through aperture (16) by mounting means consisting of tab (22), neck (24), and collar (26). Filament holder (12) releasably contains a filament (14) which extends beyond housing (4) and provides a trimming function outside housing (4).

Abstract: Safety Rotary Lawnmower Disc Blade that uses vacuum to draw flexible material to the cutting edge but will not suck up rigid materials. Both the vacuum generating element and cutting edge are located on the same side of the disc blade.

Abstract: A serrated blade to be mounted on a mowing machine has a plurality of fingers arranged at regular intervals along the circumference of an imaginary circle and a plurality of sawteeth are provided between adjacent fingers. The sharp-pointed ends of the sawteeth define points of a substantially circular arc which has a smaller radius of curvature than the imaginary circle and is eccentric thereto so that each of the fingers is radially recessed on one side thereof.

Abstract: In a mower having a frame and a plurality of rotatable disks supported by the frame, a driving device is operable to rotate each disk, and includes a driving wheel associated with each disk, and a shaft in driven connection with a corresponding driving wheel. A coupling in driven connection with a corresponding shaft for coupling a corresponding disk to the corresponding shaft is provided, and an antifriction bearing guides the corresponding shaft. Each driving wheel and its corresponding shaft, coupling and anti-friction bearing constitutes a separately replaceable subassembly in the mower.

Abstract: A cutting head assembly for a rotary motor is disclosed characterized by a flat disc member having a plurality of holes which are provided with a leading edge. A plurality of radially disposed holes are provided for insertion of a monofilament line which is the cutting element. A bar support is provided to prevent the accidental dislodging of the monofilament line.

Abstract: A rotary lawn mower cutter member in the form of a ring supporting a plurality of grass cutters each in the form of an helical torsion spring having a leg projecting beyond the periphery of the ring. The helical springs are mounted in holders removably attached to the ring such that, upon striking an obstacle, the spring projecting leg is yieldably deflected. The ring is connected to a hub by spokes and the hub is mounted on the end of the power output shaft of a rotary lawn mower.

Abstract: A machine for cutting grass and the like having a flexible strip-like cutting member supported by a disc within a housing. The strip-like member is mounted vertically and the housing has a slope such that the strip-like member is rotated to have a horizontal leading cutting edge extending beyond the housing and an inclined trailing edge which creates a vortex effect within the housing when the strip is driven by a motor to cause grass to assume a more vertical position for cutting thereof. If the cutting edge of the strip strikes an obstacle, it will be deflected into a recess in the housing rather than propelling the obstacle which might have resulted if the blade were rigid. A bottom cover plate is removably secured to the housing to permit the disc carrying the cutting member to store the same therein. Indexing of the cutting member permits measured amounts thereof to be fed from storage.

Abstract: A powered lawn mower adapted to slice grass into small pieces and to disperse these pieces on the lawn to provide a mulch therefor to enrich the soil without impairing the appearance of the lawn. The mower includes a multi-bladed, multi-level rotor having a central hub which is driven to rotate about a vertical axis. Three sets of blades radiate from the hub in staggered relation, the first set being at the level of the hub and having the longest blade length. The second set is a step below the hub and has an intermediate blade length, and the third set is a step below the second and has the shortest blade length. The leading edges of the blades are pitched to create an air foil effect producing an updraft to raise the grass and thereby facilitate a cutting action.

Abstract: An apparatus for cutting vegetation with a rotating head carrying a flexible, non-metallic cutting line extended radially into a cutting plane. An additional length of line is extended into the cutting plane automatically during rotation of the head as its speed increases from a first magnitude to a second magnitude. A laterally displaced cam within the head moves outwardly for releasing a spool carrying coiled cutting line to advance a first angular displacement within the head. The spool rotates a second angular displacement to return the cam to its original position by the drag of the cutting line during vegetation cutting but not by free air travel. After the cutting line length extension is completed, the spool is secured by the cam at its initial position automatically against further rotation within the head.

Abstract: In a mowing implement comprising a housing and a number of cutting members rotatably journalled on said housing the danger of damage of the implement due to stones jammed between a cutting member and said housing is avoided in that each cutter is fastened to the top side of a holder skimming the top side of the housing.

Abstract: The invention is directed to a clamping system for knives with angular cross-sections, especially suited for agricultural cutting operations in which a portion of the length of the sidepiece extending the cutting edge of the knife protrudes over the knife holder when the knife is clamped, with the clamping element engaging the knife in the area of its angular bend. This system allows for a reduction of knife thicknesses while maintaining other desirable characteristics, and provides the knife with greater strength in the area stressed by bending as compared with the unclamped position of the knife.

Abstract: A filament-type vegetation trimmer has an electric motor, a head rotatable by the motor, and a supply of a filament in the head, with the filament extending from the head, whereby on rotation of the head by the motor the extending filament section can cut vegetation. The trimmer further comprises a circuit for detecting the current consumption of the motor and for generating an actual-value output corresponding thereto, an actual-value generator for generating a set-point output corresponding to the current consumption of the motor when the filament is extending from the head by less than a predetermined distance, and a comparator for comparing these outputs and generating a signal when the actual-value output is less than the set-point output.

Abstract: Blade structures useful particularly for mowing vegetation, the several embodiments of the present invention are useful with rotary lawn mowers and weed trimmers intended for mowing lawns and other vegetation with a maximum degree of cutting effectiveness and user safety. The present structures are preferably mounted to the drive shaft of a mower or trimmer in the place of a conventionally used cutting structure, usually without the need for modification of the mower or trimmer. Generally, the present structures include a plate member which acts to bend at least upper portions of vegetation downwardly to allow a cutting bar carried by the plate member to strike the vegetation at or below the bent portions to facilitate clean and rapid cutting of the vegetation.

Abstract: A rotating grass-cutting machine blade is provided at each end with a projecting member which exercises a pushing action on the cut grass pieces so as to eject the cut grass towards a discharging port formed through the rotating grass-cutting machine casing and then into a collecting vessel. The projecting members may be perforated wall blades or may consist of a comb formed by removing material from a bent portion of the blade. Each projecting member may consist of a plurality of laminae which extend parallel with respect to the longitudinal axis of the blade or may consist of a plurality of cantilevered members.

Abstract: A chuteless rotary scything mulching lawn mower is described which is particularly adapted to be powered by an electric motor including sealed motors. The cutting chamber includes a toroidal portion bounded by concentric skirt walls wherein the cross sectional area of the toroid increases towards the inner skirt. The inner skirt slopes downwardly towards the axis of the cutting blade, and terminates close thereto so as to reduce air leakage from the toroid. Air passage openings are provided into the housing on the axial side of the inner skirt through which cooling air is drawn for the motor. This air stream combines with air from the toroidal chamber which is redirected by the inner skirt wall to distribute grass cuttings over a comminuting portion of the blade. The blade is sharpened to a chisel edge along the upper surface thereof, the bevelled surface of the chisel edge functioning as an air propelling surface.

Abstract: A rotary mower has a cutting plate to which freely pivotal blades are attached by retaining pins. Instead of riveting the pins directly to a leaf spring which holds the pins in place, a keyhole slot is provided in each leaf spring and a narrow waist of the retaining pin fits into rectilinear portion of the keyhole slot and is held in position there by a holding plate riveted to the leaf spring. This allows case hardening of the entire retaining pin and prevents nonuniform stresses in the latter from causing breakage.

Abstract: A rotary blade for a pruning machine which comprises a flexible disc made from a high molecular weight elastomeric material, said disc having a plurality of blades projecting radially from the periphery of said disc and a mounting hole disposed in the center of said disc.

Abstract: A lawn care device is provided which essentially consists of support beams or rotary cutter blades which are mounted onto the vertically disposed drive shaft of conventional lawn motors. The support beams are provided with receiving means, support-like bars, trunnions and the like, for pivotably mounting work tools thereon. The work tools are moved into an operating position by the forces resulting from the rotation of the support beam and are pivoted to a non-operative position when engaging an obstacle.

Abstract: A cutting blade for brush and weed cutting machines and the like includes a unitary body with radially extending cutting arms molded from a durable high strength plastic material consisting of approximately 5% glass fiber embodied in nylon.

Abstract: A pruning boom for pruning or trimming trees, bushes, shrubs and the like. A plurality of circular saw blades are rotatably mounted on a saw carrying member. Each saw blade is positioned for rotation in a spatial plane which intersects the spatial plane containing the surface of the saw carrying member located immediately behind the saw blades at an identical non-perpendicular angle. In the preferred embodiment of the present invention, one pruning boom is mounted on each side of the front-end of an agricultural vehicle to construct a machine for pruning parallel rows of citrus trees. During such pruning operations, the angular relationship between the rotating saw blades and the saw carrying member prevents newly cut branches and limbs from wedging in the space between the saw blades and the saw carrying member. The saw blades are overlapped at their peripheries with the uppermost portion of each saw blade positioned behind the lowermost portion of the adjacent saw blade above it on the saw carrying member.

Abstract: A hollow and generally closed body 10 of a safety rotor fits on the motor shaft 12 of a rotary mower and replaces a conventional mower blade. The diameter of body 10 is from 0.5 to 0.9 times the width of the swath of the mower, and several strands 11 extend far enough outward from body 10 to cut to the full width of the swath. Spools 21 or 72 contained within the body supply the strands, and a holder responsive to centrifugal force prevents strands 11 from moving outward as body 10 rotates. The strands can be automatically replenished by a strand feeder that operates when the mower slows down and speeds up.

Abstract: A lawn trimmer has a cutting blade that is formed entirely of a flexible elastomer material, such as polyurethane. The cutting blade is a generally flat, circular plate, having a rim and a plurality of cutting teeth extending outwardly from the rim. The rim has an outer diameter, with the teeth extending outwardly from the outer diameter, and an inner diameter which defines a central opening.A securing plate is used to mount the cutting blade to the lawn trimmer. The securing plate has a central portion secured to the lawn trimmer and an outer portion that overlies the rim of the cutting blade. Various embodiments are disclosed for fixedly attaching the securing plate to the rim of the cutting blade.

Abstract: A cutting blade for a rotary mower has a generally horizontally disposed, elongated blade body adapted for rotational movement about the vertical axis thereof when operatively connected to a rotary mower, and a plurality of fins attached to the blade body, each fin extending generally vertically from the blade body and away from the vertical axis thereof and disposed at an angle to the longitudinal axis of the blade body such that the outwardly facing surface of each fin is presented to the air upon rotation of the blade. In operation, the fins force air and grass clippings upwardly and radially outwardly from the rotating cutting blade.

Abstract: A balanced mower head for carrying a plurality of monofilament lines. The mower head is suitable for being mounted on the shaft of conventional rotary mower and includes certain features which particularly adapt the head for universal fit and for replacing the conventional mower blade with monofilament cutting lines thereby substantially enhancing the safety of the cutting operation. The head defines a bore extending therethrough which is proportioned for receiving the shaft which normally carries the blade of a conventional rotary mower. A plurality of line holders extend outwardly from the head body and define at their outboard end portions an opening which is proportioned for receiving a line such that the line extends outwardly from the outboard end portion of each of the line holders to perform the cutting operation upon rapid rotation of the head. Means are provided for generating air currents in a vertical direction during the cutting operation to stand the vegetation up prior to its being cut.

Abstract: "L" shaped spring wire blades for use on drum type mowers. The upper ends of the vertical leg portions of the L-shaped members are fastened to the drum near its upper end and arcuately spaced apart around its cylindrical surface. The vertical portion of each blade projects downwardly at a position closely adjacent the outer cylindrical surface of the drum and passes through an opening in the disc at the base of the drum whereafter the horizontal portion of each blade extends radially outwardly beneath the disc. A hay cutting end of each blade projects radially outwardly beyond the disc to effect cutting of hay as the drum and its unitary disc rotate. The spring wire blade can yield rearwardly about its vertical leg as an axis of torsional twist when its horizontal leg strikes an obstruction. The inherent spring nature of the L-shaped blade will cause it to automatically resume its cutting position when the obstruction is cleared.

Abstract: A cutting and mulching blade assembly for a rotary lawn mower characterized by being adapted for fine mulching of even long grass and blowing of the grass cuttings away from the internal surface of the shroud housing of the mower back on the lawn among the remaining grass, such as to obviate the need for raking. The self-cleaning feature also allows making the shroud housing without lateral outlets for more safety. This cutting and mulching blade assembly comprises a mulching blade made of essentially the same blank as a conventional lawn mower blade and operatively secured to such cutting blade by a hub member for bodily rotation together and with the mulching blade formed to blow the grass cuttings inward and downward back on the lawn.

Abstract: An improved lawnmower blade for cutting in a substantially horizontal position, of the type including a strip of metal having a substantially flat central region and end portions provided with cutting edges on opposite sides of the blade, the cutting edges being at a level lower than the central region in the position of operation and extending substantially parallel to the surface thereof and being joined by transitional zones to the surface of the central region; these transitional zones extend at the ends of the blade, from the cutting edges to the trailing edges of the blade respectively and which are progressively shorter with increasing distance from the ends. The improvement provides a hump formed in the blade, associated with each transitional zone, for aiding in the ejection of grass from a lawnmower. Each hump merges with its associated transitional zone and is directed towards its associated trailing edge. Advantageously, each hump has an open mouth directed towards its associated trailing edge.

Abstract: A spool feed mechanism for a non-metallic, line grass trimmer wherein the free end of the cutting line is spun at high speed for cutting vegetation, includes a spool of cutting line mounted for rotation about the central axis thereof. The spool has first and second ratchet wheels located at respective ends. Each ratchet wheel includes a set of ratchet teeth, one set of which is angularly displaced with respect to the other. A U-shaped, resilient member having first and second pawls provided on the legs thereof is mounted adjacent the spool with the pawls positioned for alternate engagement and disengagement of the respective ratchet wheels. A manually operated trigger assembly coupled to the member moves the latter from a normal position to disengage the first pawl and ratchet wheel and to engage the second pawl and ratchet wheel, whereby the spool is permitted to rotate incrementally to feed a predetermined length of cutting line.

Abstract: A mowing machine for connection to the three-point hitch of a tractor which extends laterally of the tractor. A drive of meshing pinions contained in a housing, the drive being powered via belts from the power take-off of the tractor. The drive rotates the cutting members about vertical axes which are supported by and disposed immediately above a plate-like supporting element. Plate-like connecting members connect the cutting members with the drive pinions, such connecting members rotating with the cutting members about the same axis. Adjacent cutting members rotate in opposite directions and adjacent connecting members co-operate to move cut crop to the rear relative the mowing machine in swaths by contact and air movement generated thereby. The drive pinions and the cutting members have roller bearings to minimize vibration.

Abstract: In a rotary-scythe grass mower a device is provided for impelling the grass clippings towards a porous bag or other collecting device, the device being within the mower hood and rotating with the cutter blade or blades. The device may conveniently comprise upwardly and outwardly curving tines in a rake-like or comb-like arrangement on the cutter blade or blades, and/or horizontal rods extending radially from the cutter shaft above the cutter blade or blades.

Abstract: A powered lawn mower adapted to slice grass into small pieces and to disperse these pieces on the lawn to provide a mulch therefor to enrich the soil without impairing the appearance of the lawn. The mower includes a multi-bladed, multi-level rotor having a central hub which is driven to rotate about a vertical axis. Three sets of blades radiate from the hub in staggered relation, the first set being at the level of the hub and having the longest blade length. The second set is a step below the hub and has an intermediate blade length, and the third set is a step below the second and has the shortest blade length. The leading edges of the blades are pitched to create an air foil effect producing an updraft to raise the grass and thereby facilitate a cutting action.

Abstract: A cutting blade for agricultural equipment defined by a truncated diamond configuration in plan view, where the cutting blade is made from a high strength plastic material, and where the leading or cutting edges thereof are beveled in a downward and outward direction. In an alternative embodiment, the cutting blade is in a "double diamond" shape, i.e. similar to two truncated diamond shapes at a right angle to each other. In any event, with either invention form, the cutting blade is reversible for extended use.The invention affords particular adaptability to what is presently and commercially known as home trimming and/or edging equipment; however, more far-reaching end purposes are achieved as, for example, the effective cutting of heavy grass, brush and scrub trees because of the unique shape and the material of each cutting blade per se.

Abstract: The invention is concerned with the reduction of the vibration transmitted from a mechanism having at least one element rotating at a fundamental frequency and one or more cyclically displaceable further elements connected to said rotating element, and in which the displacements of said further elements produce an aggregate cyclic linear exciting force of fundamental frequency and harmonics thereof acting on the same line. To prevent transmission of vibrations produced by said exciting force from the mechanism to its support means, the mechanism is constrained to prevent all degrees of freedom of movement relative to the support means except for movement under the influence of said linear exciting force which is thereby isolated from the support means. The mechanism also has balancing means integral with or attached to said rotating element for balancing any rotating force produced at said fundamental frequency.

Abstract: A rotary lawn mower comprises a chassis, a prime mover mounted on the chassis, and a rotating member operatively connected with the prime mover for rotation within the chassis and having a peripheral edge. A cutting blade is movably secured to the rotating member for movement between a retracted position in which the cutting blade is positioned inwardly of the peripheral edge and an extended position in which the cutting blade extends outwardly beyond the peripheral edge. A control mechanism is connected to the chassis and movable axially of the axis of rotation of the rotating member for moving the cutting blade between the retracted and extended positions.

Abstract: A cross flow rotary mower has a rotor with horizontal outer cutting edges and upwardly extending blower vanes. A conduit having upper, lower and side walls cooperates with the rotor to form a cross flow blower. The rear semi-circle of travel of the rotor is within the conduit. The inlet opens forwardly and has a lateral extent preferably as great as the diameter of the tip circle of the rotor. The cutting edges extend forward of the lower wall, and preferably the lower wall extends to the cutting edges. An extension of the upper wall extends forwardly beyond the tip circle with front and side skirt portions. Means for producing and strengthening vortex air flow are described, and also inlet air flow control vanes. A number of rotors and conduit arrangements with advantageous features are described. These include dual blower vane arrangements.

Abstract: A lawn mower blade includes a leading flat portion, at each of its opposite ends, sharpened to define a cutting edge and a trailing vane is joined to and is angled upwardly in trailing relationship to each flat portion. In one embodiment, the vanes are each in the form of a lift wing and perforations or holes are located in the leading flat portion ahead of the lift wing and provide air pressure relief passages. In another embodiment the vanes include lift wings and bagging paddles joined to the lift wings and including second leading flat portions to which trailing fins are joined. The second leading flat portion is either recessed to form a space between outer end portions of the fin and flat portion or is perforated to provide air pressure relief passages.

Abstract: Two embodiments of mowing machines wherein the cutters are resiliently deflectable to within a guard. In both embodiments, the frame of the mowing machine is connected to a tractor and extends laterally therefrom, the mowers being powered from the power take-off of the tractor by a train of gears, shafts and connecting universal joints. In one embodiment, the mowers rotate about vertical axes with the cutters being rotated on elongated resilient shafts which are also rotated about a common main axis from which they are spaced. The cutters are supported near the ground by holders which permit resilient deflection of the cutters' shafts into guards supported by the mowers when the cutters encounter obstacles or otherwise are subjected to forces which cause them to deflect. In the other embodiment, the cutters are mounted on an endless member such as a chain which runs around laterally spaced apart wheels such as sprockets which are mounted on carrier plates which are connected by a rod which is spring-biased.

Abstract: A road grader of the type including a tiltable and vertically adjustable frame is utilized to dependingly support a heavy duty multibladed horizontal rotary cutter head. The frame supports a prime mover drivingly connected to the rotary cutter head and the latter includes a horizontal disc from which elongated blades are supported. The elongated blades include base and free ends and the base ends of the blades are pivotally attached to spaced peripheral portions of the disc for oscillation relative thereto about upstanding axes. The rotary cutter head is disposed between the front steerable and rear driving wheels of the road grader and the blade frame of the grader is provided with a rearwardly opening semi-truncated cone-shaped shield within whose lower periphery the forward outer marginal portion of the disc is received and beneath whose lower periphery the free ends of the blades carried by the forward half of the rotary disc project.

Abstract: An automatic development reel type cutter head for a filament trimmer comprises a circular base member having a circular array of post-like upstanding members and a filament coil disposed about selected of the post-like upstanding members and inside of the remaining post like members. The filament coil has a free end portion which is automatically deployed outwardly from the coil as the cutter head is rotated by a drive shaft upon which the cutter head is mounted against one of the post-like members so as to project radially outwardly therefrom. As one free end portion wears and breaks off as a result of frictional contact with the post-like member from which it projects, another free end portion is automatically deployed outwardly from another post-like member. In one embodiment of the invention a filament retainer plate is disposed over only those post-like members about which the filament is to be wound.

Abstract: A clipping apparatus for bushes and grass intended to be attached to a tractor or like vehicle and comprising two rotatable blades having cutting edges. The blades are operative to produce a clipping action in co-operation with an underlying toothed means. One of the blades, when seen in the direction of movement of the apparatus, is mounted somewhat behind the other blade, and the blades are located on mutually different levels. The distance between the centers of rotation of the blades is greater than the radius of the circle defined by the tips of the cutting edges but shorter than the diameter of said circle. The blades are arranged to rotate in the same direction.

Abstract: A safety cutter blade for a rotary trimmer. The blade has a hub formed with a central opening for mounting it on the drive shaft of a rotary trimmer. Three equally angularly spaced cutting blades are formed integrally with the hub and extend outwardly from said hub. Each blade is formed with a convex rearwardly swept cutting edge which is tangential to the hub on one side of the cutting blade and a short straight forwardly swept cutting edge on the other side of each cutting blade. Either of these cutting edges is adapted to be the leading, or effective edge depending on the orientation of the blade on the drive shaft and the direction of rotation of the trimmer shaft. The safety blade is made of an elastomer reinforced with plastic fibers. A layer of coarse fabric made of threads of an organic polymer is embedded in the elastomer and intersects the cutting edges of the cutting blades.

Abstract: A safety cutter blade for a rotary trimmer. The blade has a circular hub formed with a central opening for mounting the blade on the drive shaft of a rotary trimmer. An annulus is made integral with and coplanar with the hub. A plurality of cutting teeth are formed integrally with the annulus at its periphery. Each tooth is provided with a swept convex cutting edge and a straight cutting edge on opposite sides thereof. The convex cutting edges constitute a set of negative cutting edges which force severed foliage away from the center of the blade while the straight cutting edges constitute a second set of cutting edges which are adapted to cutting short grass. Each of these sets of cutting edges is adapted to be effective when they are the leading edges of the teeth of the cutter blade which is determined by the direction of rotation of the trimmer drive shaft and the position of the blade relative thereto.

Abstract: In order to prevent the adhesion of crop to a swath board of a mowing device, the or each swath former comprises an endless member passed around a foremost and a hindmost reversing element, viewed in the direction of movement, the crop advancing run of said member being at an acute angle to the carrier.

Abstract: Mowing apparatus for connection to the lifting device of a tractor which is powered by the power take-off of the tractor. The apparatus includes a three-point trestle for mounting on the three-point lift device of the tractor, the trestle supporting a parallelogram suspension gear for the mowing component, a gear box and an intermediate telescopic driving shaft for the mowing elements. The parallelogram has a suspension gear including two foldable arm portions whereby the mowing component can be rotated upwardly for transport. The intermediate drive shaft is connected to the mowing component via a gear box. The mowing component is made up of four gear boxes each holding four side-by-side intermeshing pinions, the four gear boxes being connected by a flat frame beam across the top of same with the pinions of adjacent gear boxes being in mesh. Each pinion is journalled in bearings connected to the frame beam thereby suspending same above the bottom of the gear box.

Abstract: A lawnmower using flexible non-metallic filaments as cutting elements is disclosed. In certain specific embodiments the lawnmower may include a stored supply of four lengths of such filament, the free ends of which protrude from a member driven about a nearly vertical axis. Means for metering out line are also disclosed. The mower may include an axial flow fan mounted above the flexible filament cutting apparatus for the purpose of agitating uncut grass and for the purpose of evacuating cut grass particles from the mower housing.

Abstract: A device for mowing crop comprising a pair of discs adapted to rotate in the cutting plane, driven with equal angular speeds and pairwise in opposite senses and having each outwardly projecting cutters.A cutter may be bent upwardly due to impact on a stone.In order to avoid further damage of the device the circumferential rim of each disc is incised in between every two cutters essentially along an arc of a circle having a center of curvature located outside the circumferential rim.

Abstract: The device is applicable to a lawn mower of the rotary type having a rotor on a vertical axis, with cutting blades movable to an outer active position in which they extend radially beyond the rotor, and an inner inactive position in which they are retracted within the rotor; a solenoid is utilized to project the cutting blades to active position, and they are spring-loaded to retract them in inactive position; the solenoid is activated by a switch controlled by the usual manual traction control lever, utilized for throwing the motor into drive condition, so that the cutting blades are moved to active position automatically when the mower is put in drive condition and to inactive position when the mower is stopped; the solenoid is actuated by the magneto of the engine provided in the mower.

Abstract: Disclosed herein is a separable mower blade comprising a stem portion affixed to the drive axis of a rotary type mower shaft, a blade connected thereto and a slot disposed on the blade for reception of a bolt which is affixed to the stem portion so as to fasten the two together. A shroud is provided over the area of interconnection so as to firmly affix the two elements, the blade and the stem together and is so constructed to allow its easy removal so that blades may be taken off with a minimal amount of time and tools used therefore.

Abstract: A mowing machine has an elongated beam that supports side-by-side rotors with pivoted cutters positioned to cut overlapping paths in front of the beam. The rotor units include an upper rotatably hub with pivoted blades and lower bodies which house corresponding driving shafts. The units are releaseably fastened to the beam and in one embodiment, spaced apart supporting elements are fastened to the front side of the beam and a unit is fitted and bolted between elements. In another embodiment, the body of each unit is hollow so that the beam can be passed through units and the latter abutted to one another and secured in place with a single bolt. The driving shaft of each unit is interconnected to adjacent driving shafts by sleeve connectors that form an elongated drive shaft that is parallel and in front of the beam.