Crankshaft for reciprocating engine

Patent metadata

Field	Value
Publication number	US-10247226-B2
Application number	US-201615735496-A
Country	US
Kind code	B2
Filing date	Jun 6, 2016
Priority date	Jun 12, 2015
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

A crankshaft includes journals serving as a central axis of rotation, crank pins decentered from the journals, and crank arms connecting the journals and the crank pins. Some or all of the crank arms have counterweights integrated therewith. At least one of the crank arms has a recess in a crank pin facing surface. The crank arm includes ribs formed respectively in two side portions of the recess along a periphery of the crank arm.

First claim

The invention claimed is:

1. A crankshaft to be mounted in a reciprocating engine, the crankshaft including journals serving as a central axis of rotation, crank pins decentered from the journals, and crank arms connecting the journals and the crank pins, the crank pins being on a first end of a pair of the crank arms, the journals being on a second end of the crank arms opposite to the first end of the crank arms, wherein:
at least one of the crank arms has a counterweight integrated therewith on the second end of the at least one crank arm;
at least one of the crank arms in a selected pair of crank arms having one of the crank pins, one of the counterweights and a recess in a crank pin-facing surface, the recess extending entirely between the one crank pin and the one counterweight so as to not overlap with the one crank pin; and
the at least one crank arm includes a first rib formed only along part of a first side portion of the recess along a first periphery of the one crank arm.

2. The crankshaft according to claim 1 , wherein
the one crank arm has a second rib formed only along a part of a second side portion of the recess along a second periphery of the one crank arm.

3. The crankshaft according to claim 2 , wherein:
the first rib or the second rib extends from an end of the recess nearest to the one crank pin, to a point past the axis of rotation of the crankshaft toward the one counterweight; and
when the one crank arm is viewed from a side, an end of the first rib or the second rib nearest to the one counterweight is located in a range of the recess, the range being from a point of the axis of rotation of the crankshaft to a point nearest to the one counterweight among points of intersection between an outer periphery of one of the journals and the one crank arm, the one journal being on the second end of the one crank arm.

4. The crankshaft according to claim 3 , wherein:
when the one crank arm is viewed from the side, a face of the first rib or the second rib is parallel to a straight line connecting a point nearest to the one counterweight among points of intersection between an outer periphery of the one crank pin and the one crank arm, and a point nearest to the one counterweight among points of intersection between the outer periphery of the one journal and the one crank arm.

5. The crankshaft according to claim 1 , wherein:
the first rib extends from an end of the recess nearest to the one crank pin to a point past the axis of rotation of the crankshaft toward the one counterweight; and
when the one crank arm is viewed from a side, an end of the first rib nearest to the one counterweight is located in a range of the recess, the range being from a point of the axis of rotation of the crankshaft to a point nearest to the one counterweight among points of intersection between an outer periphery of one of the journals and the one crank arm, the one journal being on the second end of the one crank arm.

6. The crankshaft according to claim 5 , wherein:
when the one crank arm is viewed from the side, a face of the first rib is parallel to a straight line connecting a point nearest to the one counterweight among points of intersection between an outer periphery of the one crank pin and the one crank arm, and a point nearest to the one counterweight among points of intersection between the outer periphery of the one journal and the one crank arm.

Assignees

• Nippon Steel & Sumitomo Metal Corp

Inventors

• Imanishi Kenji
• Tamura Kenji
• Yoshino Ken
• Yabuno Kunihiro
• Ishihara Koichiro

Classifications

• F16C3/08 Primary

  made in one piece (features relating to lubrication F16C3/14, to cooling F16C3/16) · CPC title

• F16C3/20 Primary

  Shape of crankshafts or eccentric-shafts having regard to balancing · CPC title

• F16C2360/22

  Internal combustion engines · CPC title

• F16F15/283

  for engine crankshafts · CPC title

• F16F15/24

  of crankshaft systems by particular disposition of cranks, pistons, or the like {(shape of crankshafts or eccentric-shafts having regard to balancing F16C3/20)} · CPC title