Patent US3802080A successfully refreshed from Google Patents.
US3802080A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Safety guard for a scribe saw
Assignee: BEST AND DONOVAN
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Filing: 1972-09-29
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Granted: 1974-04-09
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Expires: 1992-09-29
Abstract
Abstract A safety guard for a scribe saw that protects the entire periphery of the saw''s circular blade when the saw is not in use, and that retracts to a preset depth for regulating the depth of cut desired when the saw is in use. The safety guard structure includes a fixed cover mounted to the saw for protecting one segment of the circular blade, and a movable cover pivotally mounted to the fixed cover for protecting the other segment. The movable cover is adapted to pivot between a closed position and an open position, the movable cover overlying the circular blade''s periphery for protecting against inadvertent contact when in the closed position and exposing the circular blade''s periphery for cutting when in the open position. A trigger is interconnected by latch linkage with the movable cover; the trigger is spring loaded toward a position at which the linkage is disposed over center so as to restrain the movable cover in the closed position against inadvertent contact, and is manually actuable out of the over center position so as to allow the movable cover to retract into the open position as the circular blade is engaged in a cutting attitude. The depth of cut is regulated by limiting retraction of the movable cover. The depth of retraction of the movable cover is adjusted by rotating a depth disc that is eccentrically mounted on the fixed cover. The disc''s periphery is in the nature of an adjustable abutment adapted to cooperate with a fixed abutment on the movable cover, the two abutments engaging or contacting one another to define the maximum limit of the movable cover''s retracting or opening movement.
Inventors
- 👤 J Peter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:05
CPC Classifications
A; A22; A22B; A22B5/00; A22B5/20; A22B5/203; A22B5/205; A22B5/206; B; B27; B27B; B27B9/00; B27B9/02; B27G; B27G19/00; B27G19/02; B27G19/04
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
333 words
A safety guard for a hand held power saw, said saw including a circular blade, comprising a fixed cover mounted to the saw to overlie one segment of the circular blade''s periphery, a movable cover pivotally mounted to the saw, said movable cover being adapted to pivot between a closed position where same overlies the other segment of the circular blade''s periphery for protecting against inadvertent contact with that other segment, and an open position where same exposes the other segment of the circular blade''s periphery for cutting, over-center type latch linkage comprising a first latch link pivotally mounted at one end to said fixed cover and a second latch link pivotally mounted at one end to said movable cover, said links being pivotally connected together at their other ends, and said links being in an over-center position to one side of an imaginary center line that connects the pivot mounting points of said two links with their respective covers when said movable cover is in the closed position, a spring connected with said latch linkage, said spring being disposed to continuously bias said latch linkage toward the over-center position, a stop mounted to the saw, said latch linkage being adapted to abut against said stop to prevent collapse of said latch linkage when said latch linkage is in the over-center position and an opening force is applied against said movable cover, thereby preventing retraction of said movable cover into the open position when said movable cover is closed, and a trigger integral with said first latch link and positioned adjacent the saw''s handle, said trigger allowing said latch linkage to be manually actuated out of the over-center position to the other side of the imaginary center line that connects the pivot mounting points of said two links with their respective covers to permit collapse of said linkage when an opening force is applied against said movable cover, thereby allowing retraction of said movable cover into the open position from the closed position.
Claim 2
Dependent Claim
333 words
A safety guard for a hand held power saw, said saw including a circular blade, comprising a fixed cover mounted to the saw to overlie one segment of the circular blade''s periphery, a movable cover pivotally mounted to the saw, said movable cover being adapted to pivot between a closed position where same overlies the other segment of the circular blade''s periphery for protecting against inadvertent contact with that other segment, and an open position where same exposes the other segment of the circular blade''s periphery for cutting, over-center type latch linkage comprising a first latch link pivotally mounted at one end to said fixed cover and a second latch link pivotally mounted at one end to said movable cover, said links being pivotally connected together at their other ends, and said links being in an over-center position to one side of an imaginary center line that connects the pivot mounting points of said two links with their respective covers when said movable cover is in the closed position, a spring connected with said latch linkage, said spring being disposed to continuously bias said latch linkage toward the over-center position, a stop mounted to the saw, said latch linkage being adapted to abut against said stop to prevent collapse of said latch linkage when said latch linkage is in the over-center position and an opening force is applied against said movable cover, thereby preventing retraction of said movable cover into the open position when said movable cover is closed, and a trigger integral with said first latch link and positioned adjacent the saw''s handle, said trigger allowing said latch linkage to be manually actuated out of the over-center position to the other side of the imaginary center line that connects the pivot mounting points of said two links with their respective covers to permit collapse of said linkage when an opening force is applied against said movable cover, thereby allowing retraction of said movable cover into the open position from the closed position.
Claim 3
Dependent Claim
69 words
A safety guard as set forth in claim 1, said movable cover, trigger, latch linkage and stop being directly connected to said fixed cover, and said fixed cover being pivotally mounted to the saw''s housing in a manner that allows the entire safety guard to pivot relative to the saw''s housing to expose fully the saw''s circular blade, thereby allowing the circular blade to be easily changed when desired.
Claim 4
Dependent Claim
210 words
A safety guard for a hand held power saw, said saw including a circular blade, comprising a fixed cover mounted to the saw to overlie one segment of the circular blade''s periphery, a movable cover pivotally mounted to the saw, said movable cover being adapted to pivot between a closed position where same overlies the other segment of the circular blade''s periphery for protecting against inadvertent contact with that other segment and an open position where same exposes that other segment of the circular blade''s periphery for cutting, latch linkage interconnected with said movable cover, said linkage being operable to restrain said movable cover in the closed position when said saw is not in use, and to allow said movable cover to retract into the open position when use of said saw is desired, an adjustable abutment in the form of a disc eccentrically mounted to one of said saw and said movable cover, said adjustable abutment being adapted to limit retraction of said movable cover to a preset depth of cut, and a fixed abutment mounted to the other of said saw and said movable cover, said depth disc''s periphery being adapted to cooperate with said fixed abutment to define the maximum limit of said movabLe cover''s open position.
Claim 5
Dependent Claim
210 words
A safety guard for a hand held power saw, said saw including a circular blade, comprising a fixed cover mounted to the saw to overlie one segment of the circular blade''s periphery, a movable cover pivotally mounted to the saw, said movable cover being adapted to pivot between a closed position where same overlies the other segment of the circular blade''s periphery for protecting against inadvertent contact with that other segment and an open position where same exposes that other segment of the circular blade''s periphery for cutting, latch linkage interconnected with said movable cover, said linkage being operable to restrain said movable cover in the closed position when said saw is not in use, and to allow said movable cover to retract into the open position when use of said saw is desired, an adjustable abutment in the form of a disc eccentrically mounted to one of said saw and said movable cover, said adjustable abutment being adapted to limit retraction of said movable cover to a preset depth of cut, and a fixed abutment mounted to the other of said saw and said movable cover, said depth disc''s periphery being adapted to cooperate with said fixed abutment to define the maximum limit of said movabLe cover''s open position.
Claim 6
Dependent Claim
45 words
A safety guard as set forth in claim 3, said depth disc being mounted to said fixed cover and positioned in the same plane as the upper section of said movable cover, said movable cover''s fixed abutment being the upper edge of said movable cover.
Claim 7
Dependent Claim
82 words
A safety guard as set forth in claim 3, said movable cover, latch linkage and adjustable abutment being all directly connected to said fixed cover, and said fixed cover being pivotally mounted to the saw''s housing, said fixed cover being maintained in fixed relation to the saw''s housing in a manner that allows the entire safety guard to pivot relative to the saw''s housing to expose fully the saw''s circular blade, thereby allowing the circular blade to be easily changed when desired.
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) | 1977-04-08 | 1977-10-08 | 1978-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-08 | 1981-10-08 | 1982-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-08 | 1985-10-08 | 1986-04-09 | $7700.00 | Window Closed / Lapsed |