Plate type nail holder for edgers, trimmers, or other applications

Claim 2

A rotary cutting head for a lawn edger having a drive shaft comprising a driven plate stationarily mounted on the shaft, a pressure plate mounted on said shaft and movable axially thereon toward and away from the driven plate, means biasing the pressure plate toward the driven plate, a cutter element retaining plate journaled on said shaft and disposed between the driven plate and pressure plate, a plurality of radially extending cutter elements carried by said retaining plate, said retaining plate including mounting means for the cutter elements, each of said cutter elements having a headed inner end and a shank, said mounting means including radially extending recess means in the retaining plate for receiving the headed inner end and adjacent portion of the shank of the cutter element whereby the pressure plate will retain the cutter elements mounted on the retaining plate and bias the driven plate, retaining plate and pressure plate toward each other for frictionally driving the retaining plate and pressure plate from the driven plate and enabling slippage of the driven plate in the event the cutter elements engage an obstruction.

Claim 3

The structure as defined in claim 1 wherein said recess means in the retaining plate includes a through hole in said retaining plate spaced inwardly from the peripheral edge thereof and a radial groove in the surface of the retaining plate facing the pressure plate and communicating with the hole and peripheral edge of the retaining plate with the headed inner end of the cutter element being disposed in the hole and the shank of the cutter element being disposed in the groove to retain the shank of the cutter element in radial relation to the rotational axis of the retaining plate.

Claim 4

The structure as defined in claim 2 wherein said pressure plate includes an annular recess in alignment with the three holes in the retaining plate for partially receiving the headed inner end of the cutter elements, said pressure plate including an annular flat surface outwardly of the annular recess for engaging the grooved surface of the retaining plate for retaining the shanks of the cutter elements in the grooves and frictionally engaging the retaining plates when thE shanks are no greater in diameter than the depth of the grooves and frictionally engaging the cutter elements when the diameter of the shanks is greater than the depth of the grooves.

Claim 5

The structure as defined in claim 3 wherein said driven plate and retaining plate have contacting flat surfaces for frictionally driving the retaining plate from the driven plate, said biasing means including a coil spring mounted on said shaft with one end of the spring engaging the pressure plate in opposed relation to the driven plate, and collar means on said shaft engaging the other end of the spring and being adjustably secured longitudinally on the shaft for varying the pressure exerted on the pressure plate by the spring.

Claim 6

The structure as defined in claim 3 wherein each through hole in the retaining plate includes a pair of radially disposed communicating axially extending apertures with the radially inner aperture being larger than the radially outer aperture thereby enabling cutter elements having different sized headed inner ends to be supported from the retaining plate.

Claim 7

The structure as defined in claim 5 wherein each of said cutter elements is in the form of a nail, a tubular sleeve rotatably supporting said drive shaft, and a drive pulley on the drive shaft adjacent the end of the sleeve remote from the plates.

Claim 8

A rotary cutting head comprising a rotary shaft, a first plate mounted on said shaft, a second plate mounted on said shaft, an intermediate plate mounted on said shaft between the first and second plates, a plurality of radially extending nails each having a headed end carried by said intermediate plate, said plates being mounted on said shaft for relative movement toward and away from each other for frictional engagement, one of said plates being fixed to said shaft for driving all of the plates and the nails, said intermediate plate including radially extending recess means receiving the headed inner end and an adjacent shank portion of a nail, said recess means including a radially extending groove in one surface of the intermediate plate and an enlarged recess at the inner end of the groove receiving the headed inner end of the nail for retaining the nail in radial relation to the rotational axis of the shaft with the frictional engagement between the plates driving all of the plates and the nails and enabling the intermediate plate with the nails mounted thereon to slip in the event the nails engage an obstacle, and means adjustably urging the first and second plates towards each other for frictionally clamping the intermediate plate therebetween.

Claim 9

A rotary cutting head comprising a rotary shaft, a first plate mounted on said shaft, a second plate mounted on said shaft, an intermediate plate mounted on said shaft between the first and second plates, a plurality of radially extending nails each having a headed end carried by said intermediate plate, said plates being mounted on said shaft for relative movement toward and away from each other for frictional engagement, one of said plates being fixed to said shaft for driving all of the plates and the nails, said intermediate plate including radially extending recess means receiving the headed inner end and an adjacent shank portion of a nail, said recess means including a radially extending groove in one surface of the intermediate plate and an enlarged recess at the inner end of the groove receiving the headed inner end of the nail for retaining the nail in radial relation to the rotational axis of the shaft with the frictional engagement between the plates driving all of the plates and the nails and enabling the intermediate plate with the nails mounted thereon to slip in the event the nails engage an obstacle, and means adjustably urging the first and second plates towards each other for frictionally clamping the intermediate plate therebetween.