US3903995A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Balancing system
Assignee: Outboard Marine Corp
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Filing: 1973-07-16
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Granted: 1975-09-09
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Expires: 1993-07-16
Abstract
Abstract Disclosed herein is a chain saw including a balanced two-stroke single cylinder engine in which balancing is provided, at least in part, exteriorly of the crankcase so as to maintain the volume of the crankcase as small as practical and thereby improve crankcase pumping action. More specifically, in the disclosed construction, rotary counterweights are carried at opposite ends of an engine block exteriorly of the crankcase. In one embodiment of the invention, one of the counterweights is driven by the same pinion which drives the chain sprocket. In another embodiment of the invention, one of the rotary counterweights is also a part of a lubricating oil pump.
Inventors
- 👤 Finn T Irgens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:38
CPC Classifications
B; B27; B27B; B27B17/00; B27B17/12; B27B17/0033; F; F02; F02B; F02B63/00; F02B63/02; F02B75/00; F02B75/007; F02B75/16; F16; F16F; F16F15/00; F16F15/22; F16F15/26; F16F15/264; F16N; F16N13/00; F16N13/02; F16N13/06; F16N13/10; F02B75/02; F02B2075/022; F02B2075/025; F02B61/00; F02B61/04; F02B61/045; F02B67/00; Y; Y10; Y10T; Y10T83/00; Y10T83/263
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
370 words
A chain saw including an internal combustion engine comprising an engine block defining a crankcase and a cylinder extending from said crankcase, a piston reciprocable in said cylinder, a connecting rod connected to said piston, a crankshaft rotatably mounted by said engine block and including first and second end portions coaxial with said crankshaft rotational axis and extending exteriorly of said crankcase from the opposite sides of said engine block, a crank pin offset form the crankshaft rotational axis and located within said crankcase, and first and second crank cheeks located within said crankcase and connecting the ends of said crank pin to said first and second crankshaft end portions, a first pinion mounted on said first crankshaft end portion exteriorly of said crankcase, a second pinion mounted on said second crankshaft end portion exteriorly of said crankcase, a first gear mounted on said engine block exteriorly of said crankcase and in mesh with said first pinion for rotation about an axis parallel to said crankshaft rotational axis, and a second gear mounted on said engine block exteriorly of said crankcase and in mesh with said second pinion for rotation about an axis parallel to said crankshaft rotational axis and in the plane defined by said crankshaft axis and said first gear axis, a member rotatably journalled in said block about an axis parallel to said crankshaft axis and driven by one of said first and second crankshaft end portions, said member having an axial bore offset from the axis of rotation of said member, a lubricant pumping element reciprocably movable in said bore, means for reciprocating said pumping element in said bore in response to rotation of said member and including a spring in said bore seated against the inner end of said element and urging said element outwardly of said bore and cam means fixed on said engine block and engaged by the outer end of said element in response to the action of said spring, whereby to effect reciprocation of said member in response to rotation of said member, and porting means selectively communicating with said bore in response to rotation of said member for supplying lubricant to said bore and for delivering lubricant from said bore.
Claim 2
Dependent Claim
370 words
A chain saw including an internal combustion engine comprising an engine block defining a crankcase and a cylinder extending from said crankcase, a piston reciprocable in said cylinder, a connecting rod connected to said piston, a crankshaft rotatably mounted by said engine block and including first and second end portions coaxial with said crankshaft rotational axis and extending exteriorly of said crankcase from the opposite sides of said engine block, a crank pin offset form the crankshaft rotational axis and located within said crankcase, and first and second crank cheeks located within said crankcase and connecting the ends of said crank pin to said first and second crankshaft end portions, a first pinion mounted on said first crankshaft end portion exteriorly of said crankcase, a second pinion mounted on said second crankshaft end portion exteriorly of said crankcase, a first gear mounted on said engine block exteriorly of said crankcase and in mesh with said first pinion for rotation about an axis parallel to said crankshaft rotational axis, and a second gear mounted on said engine block exteriorly of said crankcase and in mesh with said second pinion for rotation about an axis parallel to said crankshaft rotational axis and in the plane defined by said crankshaft axis and said first gear axis, a member rotatably journalled in said block about an axis parallel to said crankshaft axis and driven by one of said first and second crankshaft end portions, said member having an axial bore offset from the axis of rotation of said member, a lubricant pumping element reciprocably movable in said bore, means for reciprocating said pumping element in said bore in response to rotation of said member and including a spring in said bore seated against the inner end of said element and urging said element outwardly of said bore and cam means fixed on said engine block and engaged by the outer end of said element in response to the action of said spring, whereby to effect reciprocation of said member in response to rotation of said member, and porting means selectively communicating with said bore in response to rotation of said member for supplying lubricant to said bore and for delivering lubricant from said bore.
Claim 3
Dependent Claim
35 words
A chain saw in accordance with claim 1 wherein said bore is located in one of said first and second gears and has common co-axial rotation with said one of said first and second gears.
Claim 4
Dependent Claim
38 words
A chain saw in accordance with claim 1 including a saw chain drive sprocket driven by one of said first and second pinions, and wherein said member is connected to said drive sprocket and rotates in unison therewith.
Claim 5
Dependent Claim
269 words
A chain saw including an internal combustion engine comprising an engine block defining a crankcase and a cylinder extending from said crankcase, a piston reciprocable in said cylinder, a connecting rod connected to said piston, a crankshaft rotatably mounted by said engine block and including first and second end portions co-axial with said crankshaft rotational axis and extending exteriorly of said crankcase from the opposite sides of said engine block, a crank pin offset from the crankshaft rotational axis and located within said crankcase, and first and second crank cheeks located within said crankcase and connecting the ends of said crank pin to said first and second crankshaft end portions, a pinion mounted on one of said crankshaft end portions, a member rotatably journalled in said block about an axis parallel to said crankshaft axis and driven by said pinion, said member having an axial bore offset from the axis of rotation of said member, a lubricant pumping element reciprocably movable in said bore, means for reciprocating said pumping element in said bore in response to rotation of said member and including a spring in said bore seated against the inner end of said element and urging said element outwardly of said bore and cam means fixed on said blOck and engaged by the outer end of said element in response to the action of said spring, whereby to effect reciprocation of said member in response to rotation of said member, and porting means selectively communicating with said bore in response to rotation of said member for supplying lubricant to said bore and for delivering lubricant from said bore.
Claim 6
Dependent Claim
269 words
A chain saw including an internal combustion engine comprising an engine block defining a crankcase and a cylinder extending from said crankcase, a piston reciprocable in said cylinder, a connecting rod connected to said piston, a crankshaft rotatably mounted by said engine block and including first and second end portions co-axial with said crankshaft rotational axis and extending exteriorly of said crankcase from the opposite sides of said engine block, a crank pin offset from the crankshaft rotational axis and located within said crankcase, and first and second crank cheeks located within said crankcase and connecting the ends of said crank pin to said first and second crankshaft end portions, a pinion mounted on one of said crankshaft end portions, a member rotatably journalled in said block about an axis parallel to said crankshaft axis and driven by said pinion, said member having an axial bore offset from the axis of rotation of said member, a lubricant pumping element reciprocably movable in said bore, means for reciprocating said pumping element in said bore in response to rotation of said member and including a spring in said bore seated against the inner end of said element and urging said element outwardly of said bore and cam means fixed on said blOck and engaged by the outer end of said element in response to the action of said spring, whereby to effect reciprocation of said member in response to rotation of said member, and porting means selectively communicating with said bore in response to rotation of said member for supplying lubricant to said bore and for delivering lubricant from said bore.
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) | 1978-09-08 | 1979-03-10 | 1979-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-08 | 1983-03-10 | 1983-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-08 | 1987-03-10 | 1987-09-09 | $7700.00 | Window Closed / Lapsed |