US5347962A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Valve mechanism of internal combustion engine
Assignee: Nissan Motor Co Ltd
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Filing: 1992-06-24
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Granted: 1994-09-20
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Expires: 2012-06-24
Abstract
Abstract A valve mechanism of an internal combustion engine is of a type which has at least two cams for each intake (or exhaust) valve. One cam is shaped to allow the associated engine to exhibit a marked fuel saving characteristic and the other cam is shaped to also the engine to produce a higher torque at relatively low (or high) engine speed. Upon a cam switching between these cams, at least one of the cams is subjected to a phase change before and/or after the actual cam switching. As a result, the undesired shock at the cam switching is eliminated or at least minimized.
Inventors
- 👤 Makoto Nakamura
- 👤 Shigeru Sakuragi
- 👤 Hiroshi Komatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:03
CPC Classifications
F; F02; F02D; F02D13/00; F02D13/02; F02D13/0203; F02D13/0207; F02D13/0211; F01; F01L; F01L1/00; F01L1/26; F01L1/267; F01L1/34; F01L1/344; F01L1/34403; F01L1/34406; F02D13/0223; F02D13/0226; F02D13/023; F01L2201/00; F02D41/00; F02D41/0002; F02D2041/001; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
81 words
A valve mechanism of an internal combustion engine comprising: first and second cams which are shaped to allow the engine to produce lower and higher output torques respectively; switching means for switching between the first and second cams in accordance with an operating condition of the engine; and phase changing means for changing the phase of at least one of said first and second cams one of just before and just after the cam switching is made by said switching means.
Claim 2
Dependent Claim
81 words
A valve mechanism of an internal combustion engine comprising: first and second cams which are shaped to allow the engine to produce lower and higher output torques respectively; switching means for switching between the first and second cams in accordance with an operating condition of the engine; and phase changing means for changing the phase of at least one of said first and second cams one of just before and just after the cam switching is made by said switching means.
Claim 3
Dependent Claim
65 words
A valve mechanism as claimed in claim 1, in which said phase changing means comprises: a cam shaft on which said first and second cams are coaxially and securely mounted; a pulley driven by said engine and coaxially connected to said cam shaft to drive the same; and angular position changing means for changing an angular position of said cam shaft relative to said pulley.
Claim 4
Dependent Claim
119 words
A valve mechanism of an internal combustion engine comprising: first and second cams which are shaped to allow the engine to produce lower and higher output torques respectively; judging means for judging the time when a cam switching between said first and second cams should be made in accordance with an operating condition of the engine; cam switching means for actually carrying out the cam switching based on an information produced by said judging means; and phase changing means for changing the phase of one of said first and second cams before the cam switching actually made by said cam switching means and changing the phase of the other of said first and second cams after said cam switching.
Claim 5
Dependent Claim
119 words
A valve mechanism of an internal combustion engine comprising: first and second cams which are shaped to allow the engine to produce lower and higher output torques respectively; judging means for judging the time when a cam switching between said first and second cams should be made in accordance with an operating condition of the engine; cam switching means for actually carrying out the cam switching based on an information produced by said judging means; and phase changing means for changing the phase of one of said first and second cams before the cam switching actually made by said cam switching means and changing the phase of the other of said first and second cams after said cam switching.
Claim 6
Dependent Claim
93 words
A valve mechanism as claimed in claim 3, in which said phase changing means comprises: a cam shaft on which said first and second cams are coaxially and securely mounted; a pulley driven by said engine and coaxially connected to said cam shaft to drive the same; an angular position changing means for changing an angular position of said cam shaft relative to said pulley and thus changing the phases of said first and second cams; and control means for controlling said angular position changing means in accordance with information signals fed thereto.
Claim 7
Dependent Claim
79 words
A valve mechanism as claimed in claim 4, in which said control means operates in such a manner that upon a requirement of a cam switching from said first cam to said second cam, said first cam is subjected to a phase change from an advanced position to a normal position before the actual cam switching, and said second cam is subjected to a phase change from a delayed position to a normal position after the actual cam switching.
Claim 8
Dependent Claim
65 words
A valve mechanism as claimed in claim 5, in which the phase change of said first cam is carried out while said first cam is in operative condition and said second cam is in idling condition, and in which said phase change of said second cam is carried out while said second cam is in operative condition and said first cam is in idling condition.
Claim 9
Dependent Claim
79 words
A valve mechanism as claimed in claim 4, in which said control means operates in such a manner that upon a requirement of a cam switching from said second cam to said first cam, said second cam is subjected to a phase change from a normal position to a delayed position before the actual cam switching, and said first cam is subjected to a phase change from a normal position to an advanced position after the actual cam switching.
Claim 10
Dependent Claim
64 words
A valve mechanism as claimed in claim 7, in which the phase change of said second cam is carried out while said second cam is in operative condition and said first cam is in idling condition, and in which the phase change of said first cam is carried out while said first cam is in operative condition and said second cam is idling condition.
Claim 11
Dependent Claim
109 words
A valve mechanism of an internal combustion engine comprising: first and second cams which are shaped to allow the engine to produce lower and higher output torques respectively; judging means for judging the time when a cam switching between said first and second cams should be made in accordance with an operating condition of the engine; cam switching means for actually carrying out the cam switching based on an information produced by said judging means; and phase changing means for changing the phase of one of said first and second cams one of just before and just after the cam switching is actually made by said cam switching means.
Claim 12
Dependent Claim
109 words
A valve mechanism of an internal combustion engine comprising: first and second cams which are shaped to allow the engine to produce lower and higher output torques respectively; judging means for judging the time when a cam switching between said first and second cams should be made in accordance with an operating condition of the engine; cam switching means for actually carrying out the cam switching based on an information produced by said judging means; and phase changing means for changing the phase of one of said first and second cams one of just before and just after the cam switching is actually made by said cam switching means.
Claim 13
Dependent Claim
93 words
A valve mechanism as claimed in claim 9, in which said phase changing means comprises: a cam shaft on which said first and second cams are coaxially and securely mounted; a pulley driven by said engine and coaxially connected to said cam shaft to drive the same; an angular position changing means for changing an angular position of said cam shaft relative to said pulley and thus changing the phases of said first and second cams; and control means for controlling said angular position changing means in accordance with information signals fed thereto.
Claim 14
Dependent Claim
57 words
A valve mechanism as claimed in claim 10, in which said control means operates in such a manner that upon a requirement of a cam switching from said first cam to said second cam, said second cam is subjected to a phase change from an advanced position to a normal position just after the actual cam switching.
Claim 15
Dependent Claim
36 words
A valve mechanism as claimed in claim 11, in which the phase change of said second cam is carried out while said second cam is in operative condition and said first cam is in idling condition.
Claim 16
Dependent Claim
29 words
A valve mechanism as claimed in claim 2, in which the cam switching is actually carried out while said first and second cams are being operated in advanced phases.
Claim 17
Dependent Claim
57 words
A valve mechanism as claimed in claim 10, in which said control means operates in such a manner that upon a requirement of a cam switching from said second cam to said first cam, said first cam is subjected to a phase change from a normal position just to an advanced position after the actual cam switching.
Claim 18
Dependent Claim
36 words
A valve mechanism as claimed in claim 14, in which the phase change of said first cam is carried out while said first cam is in operative condition and said second cam is in idling condition.
Claim 19
Dependent Claim
30 words
A valve mechanism as claimed in claim 15, in which the cam switching is actually carried out while said second and first cams are being operated in normally positioned phases.
Claim 20
Dependent Claim
57 words
A valve mechanism as claimed in claim 10, in which said control means operates in such a manner that upon a requirement of a cam switching from said first cam to said second cam, said first cam is subjected to a phase change from an advanced position just to a normal position before the actual cam switching.
Claim 21
Dependent Claim
36 words
A valve mechanism as claimed in claim 17, in which the phase change of said first cam is carried out while said first cam is in operative condition and said second cam is in idling condition.
Claim 22
Dependent Claim
30 words
A valve mechanism as claimed in claim 18, in which the cam switching is actually carried out while said first and second cams are being operated in normally positioned phases.
Claim 23
Dependent Claim
57 words
A valve mechanism as claimed in claim 10, in which said control means operates in such a manner that upon a requirement of a cam switching from said second cam to said first cam, said second cam is subjected to a phase change from a normal position to an advanced position just before the actual cam switching.
Claim 24
Dependent Claim
36 words
A valve mechanism as claimed in claim 20, in which the phase change of said second cam is carried out while said second cam is in operative condition and said first cam is in idling condition.
Claim 25
Dependent Claim
29 words
A valve mechanism as claimed in claim 21, in which the cam switching is actually carried out while said second and first cams are being operated in advanced phases.
Claim 26
Dependent Claim
134 words
A valve mechanism as claimed in claim 2, in which said angular position changing means comprises: means defining a cylindrical bore in said pulley, said bore spacedly receiving therein a cylindrical end of said cam shaft thereby to defining an annular space therebetween; an annular piston coaxially disposed in said annular space; a hydraulic actuator for axially moving said annular piston in said annular space; and means for establishing a helical engagement between said piston and an inner surface of said cylindrical bore and between said piston and said cylindrical end, so that when said annular piston is axially moved by said hydraulic actuator, said pulley and said cam shaft are forced to rotate about a common axis in opposite directions thereby varying the angular position of said cam shaft relative to said pulley.
Claim 27
Dependent Claim
133 words
A valve mechanism as claimed in claim 4, in which said angular position changing means comprises: means defining a cylindrical bore in said pulley, said bore spacedly receiving therein a cylindrical end of said cam shaft thereby defining an annular space therebetween; an annular piston coaxially disposed in said annular space; a hydraulic actuator for axially moving said annular piston in said annular space; and means for establishing a helical engagement between said piston and an inner surface of said cylindrical bore and between said piston and said cylindrical end, so that when said annular piston is axially moved by said hydraulic actuator, said pulley and said cam shaft are forced to rotate about a common axis in opposite directions thereby varying the angular position of said cam shaft relative to said pulley.
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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) | 1997-09-19 | 1998-03-21 | 1998-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-19 | 2002-03-21 | 2002-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-19 | 2006-03-21 | 2006-09-20 | $7700.00 | Window Closed / Lapsed |