US5174257A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Balancer shaft for two cycle engine
Assignee: Yamaha Motor Co Ltd
•
Filing: 1991-12-30
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Granted: 1992-12-29
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Expires: 2011-12-30
Abstract
Abstract A balancer shaft arrangement for a two cycle, crankcase compression, internal combustion engine wherein the balancer shaft is driven from the crankshaft and is disposed below the crankcase and externally of it. The balancer shaft is driven from end of the crankshft and a flywheel is driven at the other end of the crankshaft. The balancer shaft axis is disposed at a lesser distance from the crankshaft axis than the radius of the flywheel so as to provide a compact assembly.
Inventors
- 👤 Toshikazu Ozawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:38
CPC Classifications
F; F16; F16F; F16F15/00; F16F15/22; F16F15/26; F16F15/264; F02; F02B; F02B67/00; F02B67/04; F02B67/06; F02B75/00; F02B75/06; F02B75/16; F02B75/18; F02B75/20; F02B75/02; F02B2075/022; F02B2075/025; F02B2075/1804; F02B2075/1812; F02B3/00; F02B3/06; Y; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2173; Y10T74/2183
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
73 words
A balancer shaft arrangement for an internal combustion engine comprising a crankcase defining at least one crankcase chamber in which a crankshaft rotates, a cylinder block extending from one side of said crankcase and defining at least one cylinder bore receiving a piston driving said crankshaft, a balancer shaft chamber contiguous to but sealed from said crankcase chamber, and a balancer shaft driven by said crankshaft and contained within said balancer shaft chamber.
Claim 2
Dependent Claim
73 words
A balancer shaft arrangement for an internal combustion engine comprising a crankcase defining at least one crankcase chamber in which a crankshaft rotates, a cylinder block extending from one side of said crankcase and defining at least one cylinder bore receiving a piston driving said crankshaft, a balancer shaft chamber contiguous to but sealed from said crankcase chamber, and a balancer shaft driven by said crankshaft and contained within said balancer shaft chamber.
Claim 3
Dependent Claim
28 words
A balancer shaft arrangement as set forth in claim 1 wherein the cylinder block extends substantially vertically and the balancer shaft axis is disposed below the crankshaft axis.
Claim 4
Dependent Claim
36 words
A balancer shaft arrangement as set forth in claim 1 wherein the engine operates on a two cycle, crankcase compression principal and further includes an induction system for delivering an air charge to the crankcase chamber.
Claim 5
Dependent Claim
28 words
A balancer shaft arrangement as set forth in claim 3 wherein the cylinder block extends substantially vertically and the balancer shaft axis is disposed below the crankshaft axis.
Claim 6
Dependent Claim
54 words
A balancer shaft arrangement as set forth in claim 4 wherein the balancer shaft is driven from the crankshaft by a belt drive embodying tension and idler pulleys disposed on opposite sides of the balancer shaft axis for rotating the balancer shaft in a direction opposite to the direction of rotation of the crankshaft.
Claim 7
Dependent Claim
42 words
A balancer shaft arrangement as set forth in claim 1 wherein the balancer shaft is driven at one end of the crankshaft and wherein a flywheel is affixed to the opposite end of the crankshaft for providing an output from the engine.
Claim 8
Dependent Claim
32 words
A balancer shaft arrangement as set forth in claim 6 wherein the balancer shaft axis is disposed at a lesser distance from the crankcase shaft axis then the radius of the flywheel.
Claim 9
Dependent Claim
28 words
A balancer shaft arrangement as set forth in claim 7 wherein the cylinder block extends substantially vertically and the balancer shaft axis is disposed below the crankshaft axis.
Claim 10
Dependent Claim
36 words
The balancer shaft arrangement as set forth in claim 6 wherein the engine operates on a two cycle, crankcase compression principal and further includes an induction system for delivering an air charge to the crankcase chamber.
Claim 11
Dependent Claim
28 words
A balancer shaft arrangement as set forth in claim 9 wherein the cylinder block extends substantially vertically and the balancer shaft axis is disposed below the crankshaft axis.
Claim 12
Dependent Claim
54 words
A balancer shaft arrangement as set forth in claim 10 wherein the balancer shaft is driven from the crankshaft by a belt drive embodying tension and idler pulleys disposed on opposite sides of the balancer shaft axis for rotating the balancer shaft in a direction opposite to the direction of rotation of the crankshaft.
Claim 13
Dependent Claim
106 words
A balancer shaft arrangement for an internal combustion engine comprising a crankcase defining at least one crankcase chamber in which a crankshaft rotates, a cylinder block extending from one side of said crankcase and defining at least one cylinder bore receiving a piston driving said crankshaft, a balancer shaft journalled on an axis parallel to the axis of rotation of said crankshaft, and means for driving said balancer shaft from said crankshaft comprising belt drive and tension and idler pulleys disposed on opposite sides of said balancer shaft axis for rotating said balancer shaft in a direction opposite to the direction of rotation of said crankshaft.
Claim 14
Dependent Claim
106 words
A balancer shaft arrangement for an internal combustion engine comprising a crankcase defining at least one crankcase chamber in which a crankshaft rotates, a cylinder block extending from one side of said crankcase and defining at least one cylinder bore receiving a piston driving said crankshaft, a balancer shaft journalled on an axis parallel to the axis of rotation of said crankshaft, and means for driving said balancer shaft from said crankshaft comprising belt drive and tension and idler pulleys disposed on opposite sides of said balancer shaft axis for rotating said balancer shaft in a direction opposite to the direction of rotation of said crankshaft.
Claim 15
Dependent Claim
36 words
A balancer shaft arrangement as set forth in claim 12 wherein the engine operates on a two cycle, crankcase compression principal and further includes an induction system for delivering an air charge to the crankcase chamber.
Claim 16
Dependent Claim
28 words
A balancer shaft arrangement as set forth in claim 13 wherein the cylinder block extends substantially vertically and the balancer shaft axis is disposed below the crankshaft axis.
Claim 17
Dependent Claim
42 words
A balancer shaft arrangement as set forth in claim 12 wherein the balancer shaft is driven at one end of the crankshaft and wherein a flywheel is affixed to the opposite end of the crankshaft for providing an output from the engine.
Claim 18
Dependent Claim
32 words
A balancer shaft arrangement as set forth in claim 15 wherein the balancer shaft axis is disposed at a lesser distance from the crankcase shaft axis then the radius of the flywheel.
Claim 19
Dependent Claim
36 words
A balancer shaft arrangement as set forth in claim 16 wherein the engine operates on a two cycle, crankcase compression principal and further includes an induction system for delivering an air charge to the crankcase chamber.
Claim 20
Dependent Claim
28 words
A balancer shaft arrangement as set forth in claim 17 wherein the cylinder block extends substantially vertically and the balancer shaft axis is disposed below the crankshaft axis.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-12-29 | 1996-06-29 | 1996-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-29 | 2000-06-29 | 2000-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-29 | 2004-06-29 | 2004-12-29 | $7700.00 | Window Closed / Lapsed |