Patent US3810309A successfully refreshed from Google Patents.
US3810309A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protection arrangement at chain motor saws
Assignee: Individual
•
Filing: 1972-08-16
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Granted: 1974-05-14
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Expires: 1992-08-16
Abstract
Abstract A chain saw operated by an internal combustion engine in which the forces of a ''''kick-back'''' or throw resulting when the nose of the rotating chain engages a work piece, is minimized by means of a safety device which absorbs movement of the saw blade about the drive wheel axis and in which a spring-urged detent means acts normal to the plane of the blade to hold the blade in a normal, operative position; including means for shorting out the internal combustion engine by relative movement between a housing and saw blade support section; and including means for reorienting the saw blade to a normal work position after the ''''kick-back'''' force diminishes.
Inventors
- 👤 P Wiklund
- 👤 E Bang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:47
CPC Classifications
B; B27; B27B; B27B17/00; B27B17/0033; B27B17/02; B27G; B27G19/00; B27G19/003; Y; Y10; Y10T; Y10T74/00; Y10T74/20; Y10T74/20576; Y10T74/20636
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
102 words
In a power-operated chain saw including a body section and a blade holder section on which a chain saw blade is entrained, the improvement characterized in that one section has relative movement in the plane of the saw with respect to the other section; and means displaceably connected between said sections for permitting relative movement between the sections in the plane of the chain saw blade when reaction force due to ''''kickback'''' occurs, said means comprising an energy-absorbing damper device interposed between the relatively displaceable sections whereby the reaction force of a ''''kick-back'''' of the blade is absorbed by the body section.
Claim 2
Dependent Claim
102 words
In a power-operated chain saw including a body section and a blade holder section on which a chain saw blade is entrained, the improvement characterized in that one section has relative movement in the plane of the saw with respect to the other section; and means displaceably connected between said sections for permitting relative movement between the sections in the plane of the chain saw blade when reaction force due to ''''kickback'''' occurs, said means comprising an energy-absorbing damper device interposed between the relatively displaceable sections whereby the reaction force of a ''''kick-back'''' of the blade is absorbed by the body section.
Claim 3
Dependent Claim
33 words
The apparatus as claimed in claim 1 in which said energy-absorbing damper device is constructed and arranged to absorb ''''kick-back'''' energy when contact between the saw blade and a work piece is interrupted.
Claim 4
Dependent Claim
17 words
The apparatus as claimed in claim 1 in which the energy-absorbing damper device is a return spring.
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) | 1977-05-13 | 1977-11-12 | 1978-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-13 | 1981-11-12 | 1982-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-13 | 1985-11-12 | 1986-05-14 | $7700.00 | Window Closed / Lapsed |