Patent EP0487960A1 successfully refreshed from Google Patents.
EP0487960A1
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EP
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Valve gear oiling system for overhead camshaft engine
Assignee: Tecumseh Products Co
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Filing: 1991-11-09
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Granted: —
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Expires: 2011-11-09
Abstract
Abstract A single cylinder overhead cam, internal combustion engine lubrication system where lubricating oil is pumped from a crankcase oil sump (56) through oil passages (58,60) to the upper bearings (28,42) of the crankshaft (26) and camshaft (44). The oil leaks from the bearings, adheres and flows down the shafts which is flung by rotation thereby lubricating the cam lobes (46,47) and valve tappets (48,49). Oil, accumulating in the cam chamber sump (62), lubricates the lower camshaft bearing (64) before being pumped through the closed loop circulatory system (68).
Inventors
- 👤 Eric B. Hudson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 12:36
CPC Classifications
F; F02; F02B; F02B75/00; F02B75/16; F01; F01M; F01M1/00; F01M1/02; F01M9/00; F01M9/10; F01M9/102; F01M9/106; F02B75/007; F02B75/02; F02B2075/022; F02B2075/027; F02B2275/00; F02B2275/20
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
156 words
A single cylinder, overhead cam, internal combustion engine, comprising: a crankcase (14) including a main oil sump (54) and a cam chamber (66); a vertical crankshaft (26) rotatably supported by an upper crankshaft bearing (30) and a lower crankshaft bearing in said crankcase (14); a vertical camshaft (44) rotatably supported by an upper camshaft bearing (42) and a lower camshaft bearing (64) and extending through said cam chamber (66); intake and exhaust valves (41,43); valve actuating means (48,49) operably connected to said valves (41,43); cam lobes (46,47) on said camshaft (44) operably connected with said valve actuating means (48,49); and lubrication means for supplying oil under pressure from said main oil sump (64) to said upper camshaft bearing (42), whereby said camshaft (44), said cam lobes (46,47), and said valve actuating means (48,49) are lubricated by oil falling from said upper camshaft bearing (42), adhering to said camshaft (44) and flung radially outward by camshaft rotation.
Claim 2
Dependent Claim
45 words
The engine of Claim 1, characterized in that said lubrication means comprises: an oil pump (54) in fluid communication with said main oil sump (56); oil passages formed integrally within said crankcase (14) whereby said lubrication means supplies oil to said upper crankshaft bearing (30).
Claim 3
Dependent Claim
15 words
The engine of Claim 2, characterized by an oil sump in said cam chamber (66).
Claim 4
Dependent Claim
24 words
The engine of Claim 3, characterized in that said lower camshaft bearing (64) is lubricated by oil within said cam chamber oil sump (62).
Claim 5
Dependent Claim
43 words
The engine of Claim 4, characterized in that a pressure differential between said cam chamber oil sump (62) and said main oil sump (56) assists gravity in returning excess oil in said cam chamber oil sump (62) to said main oil sump (56).
Claim 6
Dependent Claim
193 words
A single cylinder, overhead cam, internal combustion engine, comprising: a crankcase (14) including a main oil sump (54) and a cam chamber (66); a vertical crankshaft (26) rotatably supported by an upper crankshaft bearing (30) and a lower crankshaft bearing in said crankcase (14); a vertical camshaft (44) rotatably supported by an upper camshaft bearing (42) and a lower camshaft bearing (64) and extending through said cam chamber (66); an oil sump (62) located in said cam chamber for lubricating said lower camshaft bearing (64), said cam chamber oil sump (62) including recirculating means (68) for returning the oil therein to said main oil sump (54); intake and exhaust valves (41,43); valve actuating means (48,49) operably connected to said valves (41,43); cam lobes (46,47) on said camshaft (44) operably connected with said valve actuating means (48,49); and lubrication means for supplying oil under pressure from said main oil sump (54) to said upper camshaft bearing (42), whereby said camshaft (44), said cam lobes (46,47), and said valve actuating means (48,49) are lubricated by oil falling from said upper camshaft bearing (42), adhering to said camshaft (44) and flung radially outward by camshaft rotation.
Claim 7
Dependent Claim
25 words
The engine of Claim 6, characterized in that said lubrication means comprises an oil pump (54) in fluid communication with said main oil sump (56).
Claim 8
Dependent Claim
29 words
The engine of Claim 7, characterized in that said lubrication means includes oil passages formed integrally within said crankcase (14), and supplies oil to said upper crankshaft bearing (30).
Claim 9
Dependent Claim
19 words
The engine of Claim 7, characterized in that said lubrication means supplies oil to said upper crankshaft bearing (30).
Claim 10
Dependent Claim
15 words
The engine of Claim 7, characterized in that said valve actuating means are tappets (48,49).
References Cited (Backward Citations)
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