Brush cutting blade

• US 4,989,489 A
• Filed: 06/23/1989
• Issued: 02/05/1991
• Est. Priority Date: 11/12/1986
• Status: Expired due to Term

• Current Assignee: Pinney J. Dana
• Original Assignee: Pinney J. Dana
• Inventors: Pinney, J. Dana
• Primary Examiner(s): Phan, Hien H.
• Assistant Examiner(s): Jones, Eugenia A.
• Application Number:
  US07/370,697
• Time in Patent Office: 592 Days
• Field of Search: 83/835, 83/837, 83/839, 83/844, 83/848, 83/834, 83/833, 83/840, 83/841, 83/846
• US Class Current: 83/840
• CPC Class Codes: B23D 61/021 Types of set; Variable teeth, e.g. variable in height or gullet depth: Varying pitch; Details of gullet
• CPC Class Codes: B23D 61/06 in exchangeable arrangement
• CPC Class Codes: B27B 33/141 with means to control the depth of cut
• CPC Class Codes: Y10T 83/9331 By independent connecting element
• CPC Class Codes: Y10T 83/9341 Rectilinearly movable
• CPC Class Codes: Y10T 83/935 Plural tooth groups

Abstract

Circular brush cutting blade for powered brush cutter has cutting teeth arranged in pairs on periphery of blade, the teeth in pairs being of alternate right and left configuration and closely spaced together, the pairs of teeth being relatively widely spaced apart on the blade. Means are provided to engage the kerf sides and deflect the blade toward its central plane as it engages the material being cut.

Claims

1. A brush cutting blade for a motor driven brush cutting machine, said blade comprising,

a circular disc having opposite planar parallel side surfaces and a smooth generally continuous periphery,

and a plurality of cutter teeth individually attached to the periphery of said disc,

said teeth being of alternating left and right configuration and being mounted alternately on opposite sides of said disc, there being a plurality of pairs of said teeth,

each of said teeth comprising a flat plate portion abutting one of said side surfaces of said disc,

fastener means extending through each of said tooth plate portions and said disc rigidly to secure said teeth to said disc,

each of said teeth having a single cutter element consisting of a side wall portion integral with said plate portion and an outer flange portion,

said side wall portion being laterally offset from said plate portion, the amount of offset progressively decreasing from a forward end to a rearward end thereof,

said flange portion extending from said side wall portion substantially at right angles to said disc side surfaces across the median plane of said disc,

said flange portion being inclined downwardly at an angle of between seven and ten degrees with respect to a plane perpendicular to a radius of said disc intersecting a forward edge of said flange portion,

a forward edge of said side wall portion and the forward edge of said flange portion of each tooth being formed with a beveled surface defining a cutting edge,

and a depth gauge integral with a forward end portion of each tooth plate portion positioned forwardly of said cutter element to define a gullet therebetween, said depth gauge defining an upwardly facing flat surface sloping upwardly from a leading edge to a trailing edge at an angle of between twenty-five and thirty-five degrees with respect to a plane parallel to the axis of said disc and normal to a radius of the disc intersecting the trailing edge of said depth gauge,

said depth gauge surface having a width of between 0.075 to 0.275 inch,

the trailing edge of said depth gauge being spaced between 0.020 and 0.035 inch below the cutting edge of said flange portion,

the periphery of said disc being cut away opposite each tooth from a point adjacent a rearward end of the said flange portion to the leading edge of said depth gauge portion, each tooth being mounted on said blade with the trailing edge of said depth gauge positioned between about 0.025 and 0.035 inch outwardly from the arc of the blade periphery and with a rearward top edge of said flange portion positioned substantially flush with the periphery of said blade,

said pairs of teeth each comprising a right and a left hand tooth spaced apart circumferentially a distance no greater than about the length of a tooth,

said pairs being spaced apart a distance equal to several times the length of a tooth.

2. A brush cutting blade, as set forth in claim 1, wherein said teeth of a pair are spaced apart between 0.150 and 0.687 inches.

3. A brush cutting blade, as set forth in claim 2, wherein said disc has a diameter of at least eight inches and said pairs of teeth are spaced apart a distance in excess of four inches.

4. A cutting blade, as set forth in claim 1, wherein said depth gauge has a width of 0.175 inch.

5. A cutting blade, as set forth in claim 1, wherein said depth gauge slopes at an angle of thirty degrees.

6. A cutting blade, as set forth in claim 1, wherein said flange portion slopes at an angle of seven degrees.

7. A cutting blade, as set forth in claim 1, wherein said cutter teeth are secured to said disc by rivets extending through said blade and teeth.

8. A brush cutting blade for a motor driven brush cutting machine;

said blade comprising a circular disc having a generally continuous periphery

a plurality of cutter elements on said blade adjacent the periphery thereof,

said cutter elements each having a kerf bottom cutting edge extending laterally across the central plane of said disc,

said cutter elements of each pair being in pairs one cutter element being of right hand configuration and the other cutter element of each pair being of left hand configuration,

the cutter elements of each pair being spaced closely together circumferentially,

said pairs being spaced apart circumferentially by a distance at least several times the spacing between the cutter elements of each pair.

9. A brush cutting blade, as set forth in claim 8, having a maximum of six pairs of cutter elements thereon.

10. A brush cutting blade, as set forth in claim 8, having three pairs of cutter elements thereon.

11. A brush cutting blade, as set forth in claim 10, wherein the cutter elements of each said pair are spaced apart no more than about 0.075 inch.

12. A brush cutting blade, as set forth in claim 8, having four pairs of cutter elements thereon.

13. A brush cutting blade, as set forth in claim 8, having five pairs of cutting elements thereon.

14. A brush cutting blade for a motor driven brush cutting machine,

said blade comprising a circular, disc having a generally continuous periphery and opposite flat sides,

a plurality of cutter teeth secured to the opposite flat sides of said disc adjacent the periphery thereof,

said cutter teeth being of alternate right and left configuration, and said cutter teeth each having means defining a cutting edge extending laterally of said blade on opposite sides thereof,

said teeth being secured in pairs, one tooth of each pair being of right hand configuration and the other tooth of each pair being of left hand configuration said teeth of each pair being spaced about the periphery, in closely adjacent relation to each other,

said pairs being spaced apart peripherally by an amount at least several times the spacing of the teeth of said pairs,

and means on said blade for engaging the sides of a kerf cut in a workpiece by said blade and deflecting said blade toward the central plane of said blade as the blade rotates through said kerf.

15. The blade, as set forth in claim 14, wherein said deflecting means comprises a wing formed by a portion of the blade adjacent its periphery bent outwardly from a side of the disc immediately preceding each said pair of cutter teeth, said wing sloping outwardly toward the next succeeding pair of teeth.

16. A blade, as set forth in claim 14, wherein said deflecting means comprises a pair of wings spaced immediately preceding each said pair of cutter teeth, each said wing being formed by a portion of the blade adjacent its periphery bent outwardly from one side of the disc immediately preceding each said pair of cutters, one of said wings of a pair being bent outwardly of one side of the blade and the other wing of a pair being bent outwardly from the other side of the blade, said wings sloping outwardly toward the next succeeding pair of teeth.

17. A blade, as set forth in claim 14, wherein said deflecting means comprises a plurality of depth gauges, one of said plurality of depth gauges being associated with each of said cutter teeth for limiting the depth of cut of said teeth,

each of said depth gauges including a portion extending outwardly from the side of said blade to which the cutter tooth is mounted,

said portion being inclined outwardly from said blade in a direction opposite the direction of rotation of said blade.

18. A brush cutting blade for a motor driven brush cutting machine, said blade comprising,

a circular disc having a smooth generally continuous periphery,

a plurality of cutter teeth of alternate right and left configuration fastened alternately in pairs to opposite sides of said disc, said teeth each comprising a flange portion extending across the blade and defining a leading cutting edge, said flange portions each sloping downwardly toward the periphery of said blade,

the cutter teeth of each pair being spaced closely together together circumferentially, said pairs being spaced apart circumferentially by a distance at least several times the spacing between the cutter teeth of each pair,

each said tooth having an integral depth gauge positioned forwardly of said cutting edge, adjacent each said tooth with each said tooth fastened to said blade with a trailing edge of the flange portion thereof substantially flush with the periphery of said blade.

19. A brush cutting blade, as set forth in claim 18, wherein said depth gauges define a cutting clearance for said cutting edges of a predetermined amount and said depth gauges project beyond said periphery by an amount equal to the distance of said cutting edge beyond said periphery minus said clearance.

20. A brush cutting blade, as set forth in claim 18, wherein the depth gauge of each said tooth includes a portion defining a surface inclined outwardly from the side of the blade to which the tooth is fastened.

21. A brush cutting blade, as set forth in claim 20, wherein each said depth gauge comprises means defining an upwardly facing surface of at least about twice the width of said blade.

22. A brush cutting blade, as set forth in claim 18, wherein said blade is formed with a plurality of wings projecting outwardly from each side of said blade, there being a pair of such wings, immediately preceding each of said pair of teeth, the wings of each pair being on opposite sides of the blade, said wings sloping outwardly towards the succeeding pair of teeth.

23. A brush cutting blade as set forth in claims 18 or 20, said depth gauge having an upwardly facing flat surface sloping upwardly from a forward edge to a rearward edge, the arc of said disc periphery intersecting said flat surface.