US3673772A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impact mowing machine
Assignee: Deere and Co
•
Filing: 1970-12-17
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Granted: 1972-07-04
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Expires: 1990-12-17
Abstract
Abstract A cylindrical mower rotor has a pair of blades fixed along diametrically opposite sides thereof and the rotor is transversely and horizontally mounted in a fore-and-aft extending housing. The rotor is driven such that the blades are moving forwardly when they reach the lower portion of their path of travel. The blades are angled to cause air to be drawn in through a duct in the forward end of the housing and the duct is so shaped and located that the air discharging therefrom creates a vacuum which lifts the grass just forwardly of the cutting blades at the lower portion of their path of travel. The lower surface of the duct includes a portion which is lower than the cutting height of the mower and which serves to bend the grass into a dense mat to prevent objects from being thrown from under the housing by the mower blades.
Inventors
- 👤 Don Earl Holzhei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:10
CPC Classifications
A; A01; A01D; A01D57/00; A01D57/01; A01D2101/00; Y; Y10; Y10S; Y10S56/00; Y10S56/08
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
344 words
A lawn mower, comprising: a mobile frame having a normal forward direction of travel and including a housing having an open bottom and being supported for movement closely adjacent the ground, said housing further including a pair of transversely spaced, fore-and-aft extending side walls; a transversely extending rotor having opposite ends rotatably mounted in said sides, blade means fixed rigidly to said rotor and having transversely extending cutting edge means located equidistant from the axis of rotation of said rotor, said cutting edge means thus tracing a cylindrical path during rotation of the rotor; said housing further having a top wall joining said side walls, said top wall being arched over said rotor and extending between and including leading and trailing end portions, the leading end portion and the bottom of the side walls being at a level no higher than the bottom of said cylindrical path and the trailing end portion being at a level approximately the same as the axis of rotation of the rotor, an air duct having an inlet extending transversely across and being adjacent the front of the housing, the duct extending into the housing forwardly of said cylIndrical path and having an upwardly and rearwardly directed discharge opening extending transversely across and being located in the lower part of the housing at approximately the same height as the bottom of said cylindrical path and being spaced from the latter and from the top of the housing so as to cause a vacuum to be formed immediately forwardly of the bottom of said cylindrical path when air is flowing from said discharge opening; said blade means being configured for drawing a substantial amount of air in through said duct during rotation of the rotor, the blade means being the sole means for causing air to pass through said duct during rotation of the rotor; and motor means mounted on said frame and being operatively connected to said rotor for rotating the latter in a direction for carrying the blade means forwardly along the bottom portion of said cylindrical path.
Claim 2
Dependent Claim
344 words
A lawn mower, comprising: a mobile frame having a normal forward direction of travel and including a housing having an open bottom and being supported for movement closely adjacent the ground, said housing further including a pair of transversely spaced, fore-and-aft extending side walls; a transversely extending rotor having opposite ends rotatably mounted in said sides, blade means fixed rigidly to said rotor and having transversely extending cutting edge means located equidistant from the axis of rotation of said rotor, said cutting edge means thus tracing a cylindrical path during rotation of the rotor; said housing further having a top wall joining said side walls, said top wall being arched over said rotor and extending between and including leading and trailing end portions, the leading end portion and the bottom of the side walls being at a level no higher than the bottom of said cylindrical path and the trailing end portion being at a level approximately the same as the axis of rotation of the rotor, an air duct having an inlet extending transversely across and being adjacent the front of the housing, the duct extending into the housing forwardly of said cylIndrical path and having an upwardly and rearwardly directed discharge opening extending transversely across and being located in the lower part of the housing at approximately the same height as the bottom of said cylindrical path and being spaced from the latter and from the top of the housing so as to cause a vacuum to be formed immediately forwardly of the bottom of said cylindrical path when air is flowing from said discharge opening; said blade means being configured for drawing a substantial amount of air in through said duct during rotation of the rotor, the blade means being the sole means for causing air to pass through said duct during rotation of the rotor; and motor means mounted on said frame and being operatively connected to said rotor for rotating the latter in a direction for carrying the blade means forwardly along the bottom portion of said cylindrical path.
Claim 3
Dependent Claim
61 words
The invention defined in claim 1 wherein the duct has a bottom wall, a portion of which is positioned below the level of the bottom of said cylindrical path for engaging and bending over grass along the forward underside of the housing, whereby the grass will form a mat for impeding the passage of hard objects thrown by the cutting blades.
Claim 4
Dependent Claim
31 words
The invention defined in claim 1 wherein the duct is curved between its inlet and discharge openings whereby objects thrown by the blades are impeded in their passage through the duct.
Claim 5
Dependent Claim
31 words
The invention defined in claim 2 wherein the duct is curved between its inlet and discharge openings whereby objects thrown by the blades are impeded in their passage through the duct.
Claim 6
Dependent Claim
39 words
The invention defined in claim 1 wherein the top and side walls of the housing form the top and side walls of the duct and said housing further including a front plate forming the bottom wall of said duct.
Claim 7
Dependent Claim
39 words
The invention defined in claim 2 wherein the top and side walls of the housing form the top and side walls of the duct and said housing further including a front plate forming the bottom wall of said duct.
Claim 8
Dependent Claim
39 words
The invention defined in claim 3 wherein the top and side walls of the housing form the top and side walls of the duct and said housing further including a front plate forming the bottom wall of said duct.
Claim 9
Dependent Claim
39 words
The invention defined in claim 4 wherein the top and side walls of the housing form the top and side walls of the duct and said housing further including a front plate forming the bottom wall of said duct.
Claim 10
Dependent Claim
48 words
The invention defined in claim 1 and further including baffle means extending coextensively along, and adjacent to the lower rear portion of said cylindrical path for preventing the recirculation of cuttings about the rotor and for preventing air from being drawn in from the rear of the housing.
Claim 11
Dependent Claim
48 words
The invention defined in claim 2 and further including baffle means extending coextensively along, and adjacent to the lower rear portion of said cylindrical path for preventing the recirculation of cuttings about the rotor and for preventing air from being drawn in from the rear of the housing.
Claim 12
Dependent Claim
48 words
The invention defined in claim 3 and further including baffle means extending coextensively along, and adjacent to the lower rear portion of said cylindrical path for preventing the recirculation of cuttings about the rotor and for preventing air from being drawn in from the rear of the housing.
Claim 13
Dependent Claim
48 words
The invention defined in claim 4 and further including baffle means extending coextensively along, and adjacent to the lower rear portion of said cylindrical path for preventing the recirculation of cuttings about the rotor and for preventing air from being drawn in from the rear of the housing.
Claim 14
Dependent Claim
60 words
The invention defined in claim 1 wherein the forward end of said top wall is curved rearwardly and upwardly and said housing further including a transverse front plate extending between said side walls and being disposed generally parallel to the front end of said top wall, said top wall, side walls and front plate cooperating to form said air duCt.
Claim 15
Dependent Claim
64 words
The invention defined in claim 2 wherein the forward end of said top wall is curved rearwardly and upwardly and wherein the bottom wall of said duct comprises a transverse front plate extending between said side walls and being disposed generally parallel to the front end of said top wall, said top wall, side walls and front plate cooperating to form said air duct.
Claim 16
Dependent Claim
60 words
The invention defined in claim 3 wherein the forward end of said top wall is curved rearwardly and upwardly and said housing further including a transverse front plate extending between said side walls and being disposed generally parallel to the front end of said top wall, said top wall, side walls and front plate cooperating to form said air duct.
Claim 17
Dependent Claim
64 words
The invention defined in claim 4 wherein the forward end of said top wall is curved rearwardly and upwardly and wherein the bottom wall of said duct comprises a transverse front plate extending between said side walls and being disposed generally parallel to the front end of said top wall, said top wall, side walls and front plate cooperating to form said air duct.
Claim 18
Dependent Claim
35 words
The invention defined in claim 1 wherein said rotor is cylindrical and wherein said blade means includes a pair of diametrically opposite blades having continuous cutting edges extending along the entire length of the rotor.
Claim 19
Dependent Claim
30 words
The invention defined in claim 17 wherein said blades extend radially and then angularly from said rotor to the respective cutting edges in the direction of travel from the rotor.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |