| US 7,506,627 B2 | ||
| Balancer shaft arrangement for engine | ||
| Yoshiharu Nakayama, Iwata (Japan) | ||
| Assigned to Yamaha Motor Co., Ltd., Shizuoka-ken (Japan) | ||
| Filed on Aug. 17, 2005, as Appl. No. 11/205,776. | ||
| Claims priority of application No. 2004-237336 (JP), filed on Aug. 17, 2004. | ||
| Prior Publication US 2006/0037576 A1, Feb. 23, 2006 | ||
| Int. Cl. F02B 75/06 (2006.01); F16C 3/00 (2006.01); F16C 3/20 (2006.01) | ||
| U.S. Cl. 123—192.2 [464/180; 74/604] | 22 Claims |
| 1. An engine comprising:
a crankshaft including a plurality of crank weights disposed along a length of the crankshaft;
a balancer shaft defining longitudinal ends and being supported at its ends through first and second bearings by a crankcase
and being disposed generally in parallel with the crankshaft; and
a plurality of balancer weights including at least a first balancer weight disposed generally at a first longitudinal end
of the balancer shaft and at least a second balancer weight disposed generally at a second longitudinal end of the balancer
shaft, at least one of the first and second balancer weights comprising first and second weight portions, the first and the
second weight portions being disposed on opposite axial sides of the first bearing along the length of the balancer shaft;
wherein the first balancer weight is disposed on an axially outer side of the balancer shaft relative to a first outermost
crank weight and the second balancer weight is disposed on an axially outer side of the balancer shaft relative to a second
outermost crank weight, wherein the first and second outermost crank weights are disposed at opposing ends of the crankshaft.
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