Crankshaft bearing support structure

• US 10,641,337 B2
• Filed: 01/18/2018
• Issued: 05/05/2020
• Est. Priority Date: 01/19/2017
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toyota Jidoshokki (Toyota Motor Corporation)
• Original Assignee: Kabushiki Kaisha Toyota Jidoshokki (Toyota Motor Corporation)
• Inventors: Kamiya, Yoshiaki
• Primary Examiner(s): Steckbauer, Kevin R
• Application Number:
  US15/873,982
• Publication Number:
  US 20180202389A1
• Time in Patent Office: 838 Days
• CPC Class Codes: F02F 7/0053 Crankshaft bearings fitted in the crankcase
• CPC Class Codes: F16C 17/022 with a pair of essentially semicircular bearing sleeves
• CPC Class Codes: F16C 35/00 Rigid support of bearing units; Housings, e.g. caps, covers F16C23/00 takes precedence
• CPC Class Codes: F16C 35/02 in the case of sliding-contact bearings
• CPC Class Codes: F16C 35/067 Fixing them in a housing with interposition of an element F16C35/07
• CPC Class Codes: F16C 39/02 using mechanical means
• CPC Class Codes: F16C 9/02 Crankshaft bearings
• CPC Class Codes: F16C 9/03 Arrangements for adjusting play

Abstract

A crankshaft bearing support structure includes a cylinder block having a first holding portion; a first plain bearing held by the first holding portion of the cylinder block; a crank cap fastened to the cylinder block, the crank cap having a second holding portion; a second plain bearing held by the second holding portion of the crank cap; and a crankshaft having an axis of rotation, the crankshaft being rotatably held by the first plain bearing and the second plain bearing and configured to receive an explosive load from a piston via a connecting rod. The crankshaft flexes, when subjected to the explosive load, in a direction of the explosive load. The crank cap in provided with a mechanism which causes the second holding portion to flex in a manner that a bearing holding surface of the second holding portion follows flexure of the crankshaft subjected to the explosive load.

Claims

1. A crankshaft bearing support structure, comprising:

a cylinder block having a first holding portion;

a first plain bearing held by the first holding portion of the cylinder block;

a crank cap fastened to the cylinder block, the crank cap having a second holding portion;

a second plain bearing held by the second holding portion of the crank cap; and

a crankshaft having an axis of rotation, the crankshaft being rotatably held by the first plain bearing and the second plain bearing and configured to receive an explosive load from a piston via a connecting rod,

wherein the crankshaft flexes, when subjected to the explosive load, in a direction of the explosive load, and

the crank cap includes pairs of bolt-fastening points, the bolt-fastening points in the pairs being located on opposite sides of the second holding portion in an axial direction of the crankshaft and being located on opposite sides of the crankshaft when viewed from the axial direction of the crankshaft, and

the bolt-fastening points in the pairs are provided in projecting portions projecting from opposite surfaces of the second holding portion in the axial direction of the crankshaft and integrally formed with the second holding portion, and the crank cap includes surfaces facing the cylinder block and provided with grooves between the second holding portion and the projecting portions, the grooves extending in a direction that intersects the axial direction of the crankshaft, so that the second holding portion flexes in a manner that a bearing holding surface of the second holding portion follows flexure of the crankshaft subjected to the explosive load.

2. The crankshaft bearing support structure according to claim 1, wherein

the crank cap further includes one of an arcuate groove and an arcuate through-hole provided in the second holding portion, formed along an arcuate surface of the second holding portion which holds the second plain bearing, and having a depth in the axial direction of the crankshaft.

3. The crankshaft bearing support structure according to claim 1, wherein

the crank cap further includes round or plain chamfered edges provided in a surface of the second holding portion facing the cylinder block.