Oil passage structure for engine

Patent metadata

Field	Value
Publication number	US-2019301317-A1
Application number	US-201916364670-A
Country	US
Kind code	A1
Filing date	Mar 26, 2019
Priority date	Mar 29, 2018
Publication date	Oct 3, 2019
Grant date	—

Abstract

An engine oil passage structure for an engine contributing to downsizing the engine and achieving protection of an oil passage against external forces is provided. Provided is an oil passage structure for an engine installed in a small vehicle, the engine including an engine body formed of a crankcase and a cylinder block and a cylinder head stacked inclined vehicle frontward on the crankcase, the crankcase, the cylinder block, and the cylinder head being integrally fastened. The oil passage structure includes, near a bent part formed by a case front wall of the crankcase and a cylinder front wall of the cylinder block forming a valley part by an obtuse angle, a right-left direction oil passage extending in a right-left direction along the valley part.

First claim

What is claimed is:

1 . An oil passage structure for an engine installed in a small vehicle, the engine including an engine body formed of a crankcase and a cylinder block and a cylinder head stacked inclined vehicle frontward on the crankcase, the crankcase, the cylinder block, and the cylinder head being integrally fastened, the engine body including an oil passage for supplying oil to a valve gear provided at the cylinder head, the oil passage structure comprising:
near a bent part formed by a case front wall of the crankcase and a cylinder front wall of the cylinder block forming a valley part by an obtuse angle, a right-left direction oil passage extending in a right-left direction along the valley part.

2 . The oil passage structure for an engine according to claim 1 , wherein the right-left direction oil passage is formed at the case front wall.

3 . The oil passage structure for an engine according to claim 1 , further comprising:
a return oil passage for returning oil from the cylinder head to an oil pan provided below the crankcase, the return oil passage being formed to extend in a top-bottom direction at the front wall of the engine body, wherein the right-left direction oil passage is positioned inner than the return oil passage at the front wall.

4 . The oil passage structure for an engine according to claim 1 , further comprising:
a front-rear direction oil passage formed to extend in a front-rear direction at one of right and left side walls of the engine body, wherein the front-rear direction oil passage is an outer piping where an oil passage pipe forming the front-rear direction oil passage is exposed outside.

5 . The oil passage structure for an engine according to claim 4 , wherein the front-rear direction oil passage is formed at a side wall of the engine body on an opposite side in the right-left direction relative to a side wall where a cam chain is provided.

6 . The oil passage structure for an engine according to claim 1 , further comprising:
at one of the right and left side walls of the engine body, a body top-bottom direction oil passage formed to extend in the top-bottom direction along a surface of the side wall.

7 . The oil passage structure for an engine according to claim 6 , wherein the body top-bottom direction oil passage is formed at a side wall of the engine body on an opposite side in the right-left direction relative to a side wall where a cam chain is provided.

8 . The oil passage structure for an engine according to claim 1 , wherein
the valve gear includes
a camshaft oriented in a right-left vehicle width direction and rotatably provided at the cylinder head,
a cam carrier as a cylindrical member axially slidably fitting to an outer circumference of the camshaft while prohibited from relatively rotating, a plurality of cam lobes being different in cam profile from each other being formed axially adjacent to each other in an outer circumferential surface of the cam carrier, and
a cam switch mechanism axially shifting the cam carrier to switch the cam lobes acting on a valve,
the oil passage supplying oil to the valve gear is an oil passage that supplies oil to an actuator of the cam switch mechanism, wherein the oil passage structure further comprising a head top-bottom direction oil passage formed to extend in the top-bottom direction at the side wall of the cylinder head, and the head top-bottom direction oil passage is provided between a pair of supply and discharge oil passages supplying and discharging oil to and from the actuator.

9 . The oil passage structure for an engine according to claim 2 , further comprising:
a return oil passage for returning oil from the cylinder head to an oil pan provided below the crankcase, the return oil passage being formed to extend in a top-bottom direction at the front wall of the engine body, wherein the right-left direction oil passage is positioned inner than the return oil passage at the front wall.

10 . The oil passage structure for an engine according to claim 2 , further comprising:
a front-rear direction oil passage formed to extend in a front-rear direction at one of right and left side walls of the engine body, wherein the front-rear direction oil passage is an outer piping where an oil passage pipe forming the front-rear direction oil passage is exposed outside.

11 . The oil passage structure for an engine according to claim 3 , further comprising:
a front-rear direction oil passage formed to extend in a front-rear direction at one of right and left side walls of the engine body, wherein the front-rear direction oil passage is an outer piping where an oil passage pipe forming the front-rear direction oil passage is exposed outside.

12 . The oil passage structure for an engine according to claim 2 , further comprising:
at one of the right and left side walls of the engine body, a body top-bottom direction oil passage formed to extend in the top-bottom direction along a surface of the side wall.

13 . The oil passage structure for an engine according to claim 3 , further comprising:
at one of the right and left side walls of the engine body, a body top-bottom direction oil passage formed to extend in the top-bottom direction along a surface of the side wall.

14 . The oil passage structure for an engine according to claim 4 , further comprising:
at one of the right and left side walls of the engine body, a body top-bottom direction oil passage formed to extend in the top-bottom direction along a surface of the side wall.

15 . The oil passage structure for an engine according to claim 2 , wherein
the valve gear includes
a camshaft oriented in a right-left vehicle width direction and rotatably provided at the cylinder head,
a cam carrier as a cylindrical member axially slidably fitting to an outer circumference of the camshaft while prohibited from relatively rotating, a plurality of cam lobes being different in cam profile from each other being formed axially adjacent to each other in an outer circumferential surface of the cam carrier, and
a cam switch mechanism axially shifting the cam carrier to switch the cam lobes acting on a valve,
the oil passage supplying oil to the valve gear is an oil passage that supplies oil to an actuator of the cam switch mechanism, wherein the oil passage structure further comprising a head top-bottom direction oil passage formed to extend in the top-bottom direction at the side wall of the cylinder head, and the head top-bottom direction oil passage is provided between a pair of supply and discharge oil passages supplying and discharging oil to and from the actuator.

16 . The oil passage structure for an engine according to claim 3 , wherein
the valve gear includes
a camshaft oriented in a right-left vehicle width direction and rotatably provided at the cylinder head,
a cam carrier as a cylindrical member axially slidably fitting to an outer circumference of the camshaft while prohibited from relatively rotating, a plurality of cam lobes being different in cam profile from each other being formed axially adjacent to each other in an outer circumferential surface of the cam carrier, and
a cam switch mechanism axially shifting the cam carrier to switch the cam lobes acting on a valve,
the oil passage supplying oil to the valve gear is an oil passage that supplies oil to an actuator of the cam switch mechanism, wherein the oil passage structure further comprising a head top-bottom direction oil passage formed to extend in the top-bottom direction at the side wall of the cylinder head, and the

Assignees

• Honda Motor Co Ltd

Inventors

• Iwama Takahiro
• Kataoka Dai
• Tawarada Yuichi

Classifications

• F01L2250/06

  the camshaft being driven by gear wheels · CPC title

• F01L2810/02

  Lubrication · CPC title

• F01L2001/0537

  Double overhead camshafts [DOHC] · CPC title

• F01L2820/033

  Hydraulic engines · CPC title

• F01L2013/105

  Hydraulic motors · CPC title