US3589112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thatcher attachment for rotary type lawnmower
Assignee: Individual
•
Filing: 1969-08-25
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Granted: 1971-06-29
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Expires: 1989-08-25
Abstract
Abstract A pair of generally V-shaped spring wire rake members are carried at the same radius on opposite ends of an elongated bar that is mounted at its midpoint on the lower end of the vertical driven shaft of the mower in lieu of the cutter blade. The rake members are both pivoted on vertical axes at their apex points to the underside of the bar to enable their swinging horizontally out of the way of any stone or other obstruction that might otherwise cause serious damage thereto and yet allow instant return of the rake members so deflected to normal radial operative position under centrifugal force, and the downwardly curved outer ends of each rake member are flexed upwardly by contact with the ground and are thusly maintained under spring pressure against the surface being raked and they operate at different radii to greatly increase the raking effectiveness of the attachment. Should either or both of the spring wire rake members be broken, or so badly bent out of shape as to require replacement, that is an easy matter as they are detachably secured in place by small bolts. These are shouldered to insure leaving the right amount of working clearance for pivotal movement of each rake member relative to the bar, regardless of how tightly the nuts may be fastened on the bolts.
Inventors
- 👤 Lester H Frohmader
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:11
CPC Classifications
A; A01; A01D; A01D34/00; A01D34/01; A01D34/412; A01D34/63; A01D34/82; A01D2101/00
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
125 words
An attachment for use with a rotary-type lawnmower a portable substantially horizontal housing open on the bottom and carrying a motor on the top thereof that is adapted to drive an elongated horizontal cutting blade supported at its midpoint on and rotatable on a substantially vertical axis in said housing, said attachment comprising an elongated horizontal bar adapted to be operated substantially at the level of a cutting blade and supported at its midpoint for rotation on a substantially vertical axis in said housing, and generally V-shaped rake members mounted substantially horizontally by their apex portions on the bottom of said bar in equally spaced relation to and on opposite sides of said midpoint and extending outwardly and downwardly for raking contact with the ground.
Claim 2
Dependent Claim
125 words
An attachment for use with a rotary-type lawnmower a portable substantially horizontal housing open on the bottom and carrying a motor on the top thereof that is adapted to drive an elongated horizontal cutting blade supported at its midpoint on and rotatable on a substantially vertical axis in said housing, said attachment comprising an elongated horizontal bar adapted to be operated substantially at the level of a cutting blade and supported at its midpoint for rotation on a substantially vertical axis in said housing, and generally V-shaped rake members mounted substantially horizontally by their apex portions on the bottom of said bar in equally spaced relation to and on opposite sides of said midpoint and extending outwardly and downwardly for raking contact with the ground.
Claim 3
Dependent Claim
33 words
An attachment as set forth in claim 1 wherein one arm of each V-shaped rake member is longer than the other so that their outer ends rake at different radii in said housing.
Claim 4
Dependent Claim
54 words
An attachment as set forth in claim 1 wherein said rake members are of spring wire construction and are so disposed as to elevation with respect to the ground level that the outer ends are deflected upwardly by contact with the ground, thereby causing raking contact with the ground under a predetermined spring pressure.
Claim 5
Dependent Claim
72 words
An attachment as set forth in claim 1 wherein said rake members are of spring wire construction and are so disposed as to elevation with respect to the ground level that the outer ends are deflected upwardly by contact with the ground, thereby causing raking contact with the ground under a predetermined spring pressure, the elevation of said bar relative to the ground being adjustable to increase or decrease the spring pressure.
Claim 6
Dependent Claim
79 words
An attachment as set forth in claim 1 wherein said rake members are of spring wire construction and are so disposed as to elevation with respect to the ground level that the outer ends are deflected upwardly by contact with the ground, thereby causing raking contact with the ground under a predetermined spring pressure, the elevation of said bar relative to the ground being adjustable by change in elevation of said housing to increase or decrease the spring pressure.
Claim 7
Dependent Claim
78 words
An attachment as set forth in claim 1 wherein said rake members are of spring wire construction and are so disposed as to elevation with respect to the ground level that the outer ends are deflected upwardly by contact with the ground, thereby causing raking contact with the ground under a predeterminEd spring pressure, the arms of each of said rake members being of different length so that their outer ends rake at different radii in said housing.
Claim 8
Dependent Claim
22 words
An attachment as set forth in claim 1 wherein the elongated bar carrying the rake members is substituted for the cutting blade.
Claim 9
Dependent Claim
56 words
An attachment as set forth in claim 1 wherein the rake members are pivotally mounted at their apex points on said bar on substantially vertical axes with freedom to swing out of the way of an obstruction upon contact therewith and then return under centrifugal force to their normal operative position in alignment with the bar.
Claim 10
Dependent Claim
58 words
An attachment as set forth in claim 8 wherein the rake members are held with a predetermined friction in their normal operative position in alignment with the bar so that anticipated side thrust on said members in performing the raking function is not enough to cause said rake members to swing out of aligned relationship to said bar.
Claim 11
Dependent Claim
57 words
As an article of manufacture, a spring wire rake member of generally V-shape, having a substantially horizontal circular bearing eye defined at its apex end in substantially coplanar relationship with the two diverging rake arms that are integral therewith, said arms being of different lengths, each terminating in a downwardly curved outer end portion for raking purposes.
Claim 12
Dependent Claim
57 words
As an article of manufacture, a spring wire rake member of generally V-shape, having a substantially horizontal circular bearing eye defined at its apex end in substantially coplanar relationship with the two diverging rake arms that are integral therewith, said arms being of different lengths, each terminating in a downwardly curved outer end portion for raking purposes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |