Patent US3643408A successfully refreshed from Google Patents.
US3643408A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protective device for rotary mowers
Assignee: Deere and Co
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Filing: 1970-07-20
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Granted: 1972-02-22
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Expires: 1990-07-20
Abstract
Abstract A protective device for use in conjunction with a rotary mower of the type having a housing, a vertical driven shaft extending through the housing, and a cutting blade assembly mounted on the lower end of the shaft, the assembly consisting of a center section rigidly fixed to the shaft for rotation therewith, and a pair of outer sections pivotally connected to the outer ends of the center section. The device, which serves the dual function of, first, limiting the deflection of the center blade section, and, secondly, shielding the vertical shaft and center blade section from stumps and similar obstructions, consists of a circular ring mounted on the housing concentrically with the shaft and having a lower edge terminating in close proximity to the center blade section, the outer circumference of the ring being located just inwardly of the pivotal connection between the center and outer blade sections.
Inventors
- 👤 John Kulak
- 👤 Kenneth Lawrence Kirkpatrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:27
CPC Classifications
A; A01; A01D; A01D34/00; A01D34/01; A01D34/412; A01D34/63; A01D2101/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
219 words
A mower comprising a rigid housing having a substantially horizontal top portion, drive means mounted on the top portion of said housing and including a vertical-driven shaft extending therethrough, a blade assembly connected to the lower end of said shaft for rotation therewith beneath the top portion of said housing, said blade assembly including a first blade section fixed to said shaft and extending radially outwardly therefrom, and a second blade section pivotally connected to the outer end of said first blade section, and means for limiting vertical deflection of said first blade section and for shielding said shaft from stumps and similar obstructions and also limiting horizontal movement of said second blade section, said means comprising a rigid circular ring mounted on said housing concentrically with said shaft and having a horizontal lower edge terminating in close proximity to said first blade section, the outer circumference of said ring being located just radially inwardly of the pivotal connection between said first and second blade sections, said first blade section being deflectable upwardly relative to said housing and into engagement with the lower edge of said ring upon striking an obstruction, said ring and said housing being sufficiently rigid to prevent upward deflection of said first blade section relative to said housing beyond the lower edge of said ring.
Claim 2
Dependent Claim
219 words
A mower comprising a rigid housing having a substantially horizontal top portion, drive means mounted on the top portion of said housing and including a vertical-driven shaft extending therethrough, a blade assembly connected to the lower end of said shaft for rotation therewith beneath the top portion of said housing, said blade assembly including a first blade section fixed to said shaft and extending radially outwardly therefrom, and a second blade section pivotally connected to the outer end of said first blade section, and means for limiting vertical deflection of said first blade section and for shielding said shaft from stumps and similar obstructions and also limiting horizontal movement of said second blade section, said means comprising a rigid circular ring mounted on said housing concentrically with said shaft and having a horizontal lower edge terminating in close proximity to said first blade section, the outer circumference of said ring being located just radially inwardly of the pivotal connection between said first and second blade sections, said first blade section being deflectable upwardly relative to said housing and into engagement with the lower edge of said ring upon striking an obstruction, said ring and said housing being sufficiently rigid to prevent upward deflection of said first blade section relative to said housing beyond the lower edge of said ring.
Claim 3
Dependent Claim
28 words
The invention defined in claim 1 wherein said ring includes a vertical, cylindrical wall having an upper edge disposed closely adjacent to the top portion of said housing.
Claim 4
Dependent Claim
38 words
The invention defined in claim 1 wherein said first blade section is horizontal and a lower blade section is pivotally connected to said first blade section and includes a cutting edge offset downwardly from said first blade section.
Claim 5
Dependent Claim
66 words
The invenTion defined in claim 1 wherein said first blade section is horizontal, said second blade section is pivotally mounted on the top surface of said first blade section and extends horizontally therefrom, and the outer circumference of said ring is located sufficiently inwardly of the pivotal connection between said first and second blade sections to permit said sections to assume at least a 90* angle.
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) | 1975-02-21 | 1975-08-23 | 1976-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-21 | 1979-08-23 | 1980-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-21 | 1983-08-23 | 1984-02-22 | $7700.00 | Window Closed / Lapsed |