Patent US4074869A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4074869A Expired / Lapsed US ⏱️ 0.0 years remaining

Machine for shredding leaves and garden debris

Assignee: Individual
•
Filing: 1977-03-11
•
Granted: 1978-02-21
•
Expires: 1997-03-11
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A vacuum blower-type mobile unit for shredding leaves and other garden debris. The unit comprises a pair of coaxially disposed rotors operated at respectively different speeds, the blades of the two rotors being separated by a minimum practical axial clearance to provide shredding action. Shredding is further enhanced by stationary radial blades fixed to the casing adjacent the input to the slow speed rotor, and a circular plate formed to include a large number of exit guide vanes including fixed blades disposed adjacent the output from the high speed rotor. The speed differential between the rotors and the shapes of the blades cooperate to create between them a high velocity axial stream of air and debris which moves smoothly through the machine, depositing the product in comminuted form in a bag or other container.

Inventors

  • 👤 Walter G. Johnson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 20:42
CPC Classifications
B; B02; B02C; B02C18/00; B02C18/06; A; A01; A01G; A01G3/00; A01G3/002; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18056; Y10T74/18272

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 211 words
A device for shredding garden debris which comprises in combination: a housing frame having intake, exhaust and collecting means for said debris, a main shaft journalled for rotation in said housing frame, means comprising a motor for driving said main shaft to rotate about its principal axis, a first rotor fixed for rotation by said main shaft and having a plurality of cutting blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, a second rotor axially aligned ahead of said first rotor and having a plurality of cutting blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, said rotors being constructed and arranged to provide between them a substantial axial flow of air and debris from said intake to said exhaust means, the trailing edges of the blades of said second rotor being slightly spaced apart in an axial direction in cutting relation from the leading edges of the blades of said first rotor, gear reducing means connected to said main shaft and coupled to drive said second rotor at a rotational rate which is substantially less than the rotational rate of said first rotor.
Claim 2
Independent Claim 211 words
A device for shredding garden debris which comprises in combination: a housing frame having intake, exhaust and collecting means for said debris, a main shaft journalled for rotation in said housing frame, means comprising a motor for driving said main shaft to rotate about its principal axis, a first rotor fixed for rotation by said main shaft and having a plurality of cutting blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, a second rotor axially aligned ahead of said first rotor and having a plurality of cutting blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, said rotors being constructed and arranged to provide between them a substantial axial flow of air and debris from said intake to said exhaust means, the trailing edges of the blades of said second rotor being slightly spaced apart in an axial direction in cutting relation from the leading edges of the blades of said first rotor, gear reducing means connected to said main shaft and coupled to drive said second rotor at a rotational rate which is substantially less than the rotational rate of said first rotor.
Claim 3
Dependent Claim 107 words
The combination in accordance with claim 1 wherein said gear reducing means comprises an auxiliary shaft journalled for rotation on said main shaft, a ring gear having N teeth around its inner periphery and having a collar fastened to said auxiliary shaft, a pinion gear having less than N teeth around its external periphery of substantially smaller outer diameter than the internal diameter of said ring gear and disposed to move in meshed tooth relationship around the teeth of said ring gear, and planocentric means coupled to said pinion gear to prevent said pinion gear from rotating about its own axis as it transverses said ring gear.
Claim 4
Dependent Claim 31 words
The combination in accordance with claim 1 wherein the speed of rotation of said first rotor is approximately five times as great as the speed of rotation of said second rotor.
Claim 5
Dependent Claim 40 words
The combination in accordance with claim 1 wherein the clearances between the trailing edges of the blades of said second rotor and the leading edges of the blades of said first rotor do not exceed about one-tenth of an inch.
Claim 6
Dependent Claim 29 words
The combination in accordance with claim 1 whereby said housing has a substantially uniform internal cross-sectional area throughout the entire length thereof, including said intake and said exhaust means.
Claim 7
Independent Claim 320 words
A device for shredding garden debris which comprises in combination: a housing frame having intake and collecting means for said debris, a main shaft journalled for rotation in said housing frame, means comprises a motor for driving said main shaft to rotate about its principal axis, a first rotor fixed for rotation by said main shaft and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, a second rotor axially aligned ahead of said first rotor and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, the trailing edges of the blades of said second rotor being slightly spaced apart in an axial direction from the leading edges of the blades of said first rotor, gear reducing means connected to said main shaft and coupled to drive said second rotor at a rotational rate which is substantially less than the rotational rate of said first rotor, a hub comprising a plurality of radially extended stationary blades coaxial with said rotors and disposed in fixed relation to said housing frame in a position between said intake means and said second rotor, said stationary blades having their trailing edges transversely disposed to the principal axis of said main shaft and slightly spaced apart from the leading edges of the blades of said second rotor, and a screen coaxial with said rotors and disposed in fixed relation to said housing frame in a position between said collecting means and said first rotor, said screen comprising a plurality of openings each comprising a fixed blade having a leading edge transversely disposed to the principal axis of said main shaft, the leading edges of said screen blades slightly spaced apart from the trailing edges of the blades of said first rotor.
Claim 8
Independent Claim 320 words
A device for shredding garden debris which comprises in combination: a housing frame having intake and collecting means for said debris, a main shaft journalled for rotation in said housing frame, means comprises a motor for driving said main shaft to rotate about its principal axis, a first rotor fixed for rotation by said main shaft and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, a second rotor axially aligned ahead of said first rotor and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, the trailing edges of the blades of said second rotor being slightly spaced apart in an axial direction from the leading edges of the blades of said first rotor, gear reducing means connected to said main shaft and coupled to drive said second rotor at a rotational rate which is substantially less than the rotational rate of said first rotor, a hub comprising a plurality of radially extended stationary blades coaxial with said rotors and disposed in fixed relation to said housing frame in a position between said intake means and said second rotor, said stationary blades having their trailing edges transversely disposed to the principal axis of said main shaft and slightly spaced apart from the leading edges of the blades of said second rotor, and a screen coaxial with said rotors and disposed in fixed relation to said housing frame in a position between said collecting means and said first rotor, said screen comprising a plurality of openings each comprising a fixed blade having a leading edge transversely disposed to the principal axis of said main shaft, the leading edges of said screen blades slightly spaced apart from the trailing edges of the blades of said first rotor.
Claim 9
Dependent Claim 93 words
The combination in accordance with claim 2 wherein the clearances do not exceed about one-tenth of an inch between: (a) the trailing edges of the blades of said hub comprising radially extended stationary blades and the leading edges of the blades of said second rotor; (b) the trailing edges of the blades of said second rotor and the leading edges of the blades of said first rotor; and (c) the trailing edges of the blades of said first rotor and the leading edges of the blades fixed to the openings of said screen.
Claim 10
Independent Claim 412 words
A device for shredding garden debris which comprises in combination: a housing frame having intake and collecting means for said debris, a main shaft journalled for rotation in said housing frame, means comprising a motor for driving said main shaft to rotate about its principal axis, a first rotor fixed for rotation by said main shaft and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, a second rotor axially aligned ahead of said first rotor and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft. the trailing edges of the blades of said second rotor being slightly spaced apart in an axial direction from the leading edges of the blades of said first rotor, gear reducing means connected to said main shaft and coupled to drive said second rotor at a rotational rate which is substantially less than the rotational rate of said first rotor, wherein said gear reducing means comprises an auxiliary shaft journalled for rotation on said main shaft, a ring gear having N teeth around its inner periphery and having a collar fastened to said auxiliary shaft, a pinion gear having less than N teeth around its external periphery of substanially smaller outer diameter than the internal diameter of said ring gear and disposed to move in meshed tooth relationship around the teeth of said ring gear, planocentric means coupled to said pinion gear to prevent said pinion gear from rotating about its own axis as it traverses said ring gear, wherein said planocentric means comprises a spider having two pairs of radially disposed arms extended in rectangular relation from a central hub, each of which arms is longitudinally slotted, a fixed pair of lateral projections diametrically spaced apart connected to said pinion, said lateral projections being keyed for vertical motion in one pair of slots of said spider, a second pair of spaced-apart lateral projections fixed to said housing frame being keyed for horizontal motion in the other pair of slots of said spider permitting said spider to move to and fro in a horizontal direction, whereby when said pinion moves around the teeth of said ring gear, said first pair of projections move vertically in said first pair of slots, and said spider moves laterally relative to said second pair of projections.
Claim 11
Independent Claim 412 words
A device for shredding garden debris which comprises in combination: a housing frame having intake and collecting means for said debris, a main shaft journalled for rotation in said housing frame, means comprising a motor for driving said main shaft to rotate about its principal axis, a first rotor fixed for rotation by said main shaft and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft, a second rotor axially aligned ahead of said first rotor and having a plurality of blades each shaped to include a leading edge and a trailing edge transversely disposed to the principal axis of said main shaft. the trailing edges of the blades of said second rotor being slightly spaced apart in an axial direction from the leading edges of the blades of said first rotor, gear reducing means connected to said main shaft and coupled to drive said second rotor at a rotational rate which is substantially less than the rotational rate of said first rotor, wherein said gear reducing means comprises an auxiliary shaft journalled for rotation on said main shaft, a ring gear having N teeth around its inner periphery and having a collar fastened to said auxiliary shaft, a pinion gear having less than N teeth around its external periphery of substanially smaller outer diameter than the internal diameter of said ring gear and disposed to move in meshed tooth relationship around the teeth of said ring gear, planocentric means coupled to said pinion gear to prevent said pinion gear from rotating about its own axis as it traverses said ring gear, wherein said planocentric means comprises a spider having two pairs of radially disposed arms extended in rectangular relation from a central hub, each of which arms is longitudinally slotted, a fixed pair of lateral projections diametrically spaced apart connected to said pinion, said lateral projections being keyed for vertical motion in one pair of slots of said spider, a second pair of spaced-apart lateral projections fixed to said housing frame being keyed for horizontal motion in the other pair of slots of said spider permitting said spider to move to and fro in a horizontal direction, whereby when said pinion moves around the teeth of said ring gear, said first pair of projections move vertically in said first pair of slots, and said spider moves laterally relative to said second pair of projections.

References Cited (Backward Citations)

US1137334A Cited
US2590734A Cited
US2677223A Cited
US2761332A Cited
US3011304A Cited
US3968938A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-02-20 1981-08-22 1982-02-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-02-20 1985-08-22 1986-02-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-02-20 1989-08-22 1990-02-21 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag