U.S. patent application number 10/154883 was filed with the patent office on 2003-05-01 for lubrication system for a powertrain.
Invention is credited to Bruener, Patrick J., Matuszak, Ray, Webster, David.
Application Number | 20030079710 10/154883 |
Document ID | / |
Family ID | 26851854 |
Filed Date | 2003-05-01 |
United States Patent
Application |
20030079710 |
Kind Code |
A1 |
Webster, David ; et
al. |
May 1, 2003 |
Lubrication system for a powertrain
Abstract
The engine/transmission assembly includes a first chamber, a
second chamber, and a fill hole that fluidly communicates with the
first chamber. The first chamber is capable of containing lubricant
at a first level, and the second chamber is capable of containing
lubricant at a second level. The engine/transmission assembly also
includes an opening that is between the first and second chamber
and that fluidly communicates with the first and second chamber.
The opening is positioned to maintain the first level in the first
chamber and raise the second level in the second chamber when
lubricant is added to the first chamber through the fill hole, and
to maintain these two levels when the engine is running.
Inventors: |
Webster, David; (Wauwatosa,
WI) ; Matuszak, Ray; (New Berlin, WI) ;
Bruener, Patrick J.; (Hartland, WI) |
Correspondence
Address: |
MICHAEL BEST & FRIEDRICH, LLP
100 E WISCONSIN AVENUE
MILWAUKEE
WI
53202
US
|
Family ID: |
26851854 |
Appl. No.: |
10/154883 |
Filed: |
May 24, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60351806 |
Oct 26, 2001 |
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Current U.S.
Class: |
123/196R |
Current CPC
Class: |
F02B 61/02 20130101;
F01M 11/12 20130101; F01M 11/06 20130101 |
Class at
Publication: |
123/196.00R |
International
Class: |
F01M 001/00 |
Claims
We claim:
1. An engine/transmission assembly comprising: a first chamber
capable of containing lubricant at a first level when the
engine/transmission assembly is at rest; a second chamber capable
of containing lubricant at a second level when the
engine/transmission assembly is at rest; a fill hole fluidly
communicating with the first chamber; and an opening in fluid
communication between the first chamber and the second chamber, the
opening being positioned to substantially maintain the first level
in the first chamber when the engine is at rest and raise the
lubricant in the second chamber when lubricant is added to the
first chamber through the fill hole.
2. The engine/transmission assembly of claim 1, wherein each
chamber has a bottom, the engine/transmission assembly further
comprising a drain hole fluidly communicating with the bottom of
the first chamber and the bottom of the second chamber, the drain
hole being capable of allowing lubricant to drain from the first
and second chambers.
3. The engine/transmission assembly of claim 2, further comprising
a drain plug insertable into the drain hole and capable of
preventing fluid communication between the first and second chamber
through the drain hole.
4. The engine/transmission assembly of claim 1, further comprising
a housing that includes a first side, a second side, a bottom, and
a wall that divides the first side from the second side, wherein
the first chamber is partially defined by the first side, the wall,
and the bottom, and the second chamber is partially defined by the
second side, the wall, and the bottom.
5. The engine/transmission assembly of claim 4, wherein the wall
separates the first chamber from the second chamber.
6. The engine/transmission assembly of claim 5, wherein the opening
is in the wall.
7. The engine/transmission assembly of claim 1, further comprising
a clutch assembly positioned within the first chamber.
8. The engine/transmission assembly of claim 7, further comprising
a crankshaft connected to the clutch assembly and substantially
positioned within the second chamber.
9. The engine/transmission assembly of claim 8, wherein the clutch
assembly is a least partially positioned below the opening.
10. The engine/transmission assembly of claim 9, wherein the
opening is positioned to maintain the first level such that the
clutch assembly is at least partially below the first level in the
first chamber and maintaining the second level such that the
crankshaft is entirely positioned above the second level of the
second chamber.
11. The engine/transmission assembly of claim 8, further comprising
an output shaft substantially positioned within the second chamber
and an intermediate shaft coupled to the clutch assembly in the
first chamber and coupled to the output shaft in the second
chamber, the intermediate shaft extending through the opening.
12. The engine/transmission assembly of claim 1, further comprising
a projection extending into the first chamber, wherein the
projection is positioned below the fill hole, the projection
capable of making the first level of the first chamber
substantially visually inaccessible from the outside of the first
chamber through the fill hole.
13. The engine/transmission assembly of claim 1, further comprising
a dipstick capable of measuring the second level of the second
chamber.
14. The engine/transmission assembly of claim 13, wherein the
engine/transmission assembly includes exactly one dipstick.
15. The engine/transmission assembly of claim 13, further
comprising a passageway fluidly connecting with the second chamber,
wherein the passageway extends adjacent to the first chamber, the
dipstick being insertable into the passageway and removable from
the passageway.
16. The engine/transmission assembly of claim 1, further comprising
a pump capable of removing lubricant from the second chamber, and
distributing the lubricant throughout the engine such that at least
some of the lubricant returns to the first chamber.
17. The engine/transmission assembly of claim 1, wherein the
engine/transmission assembly includes exactly one fill hole for
lubricant.
18. A method of lubricating an engine/transmission assembly having
moving parts, the method comprising: providing a first chamber
containing clutch components; providing a second chamber having a
crankshaft; providing a regulator opening between the first and
second chambers; drawing a lubricant from the second chamber to
lubricate the moving parts; returning at least some of the
lubricant used to lubricate the moving parts to the first chamber;
regulating a lubricant level in the first chamber using the
regulator opening by overflowing lubricant from the first chamber
to the second chamber when the lubricant level in the first chamber
reaches a first level.
19. The method of claim 18, further comprising: filling the first
chamber to the first level with the lubricant through a fill hole;
and filling the second chamber to a second level by overflowing
lubricant from the first chamber to the second chamber through the
regulator opening.
20. The method of claim 19, further comprising: measuring the level
of the lubricant in the second chamber with a dipstick.
21. The method of claim 18, further comprising: rotating the clutch
components at least partially below the first level.
22. The method of claim 18, further comprising: rotating the
crankshaft above the level of the lubricant in the second
chamber.
23. The method of claim 18, further comprising: removing a drain
plug to drain the lubricant from the first and second chambers.
Description
[0001] This application claims the benefit of prior filed
co-pending provisional patent application No. 60/351,806 filed on
Oct. 26, 2001.
[0002] FIELD OF THE INVENTION
[0003] The invention relates to powertrains including an engine and
a transmission, and more particularly to lubrication systems for
powertrains.
BACKGROUND OF THE INVENTION
[0004] Known powertrains generally include a crankshaft chamber
that contains a crankshaft and a clutch chamber that contains a
clutch assembly. The crankshaft chamber and the clutch chamber are
either totally separate compartments or compartments that allow
fluid communication of the lubricant.
[0005] Totally separate chambers include separate fill holes used
to introduce lubricant into each of the separate chambers and
separate dipsticks used to measure the amount of lubricant within
each of the separate chambers. Powertrains that contain separate
chambers are disadvantageous because multiple fill holes and
dipsticks increase manufacturing costs and require the operator to
check and fill multiple chambers thereby increasing maintenance
time and expense.
[0006] Known fluidly connected chambers include holes that are
positioned between the chambers to maintain the common lubricant at
the same level in each chamber. These types of engines are
disadvantageous because the level of the lubricant in the
crankshaft chamber should be maintained below the crankshaft for
efficient operation, however this level is inadequate to provide
sufficient lubrication for the clutch assembly in the clutch
chamber.
SUMMARY OF THE INVENTION
[0007] The engine/transmission assembly or powertrain of the
present invention efficiently operates the crankshaft above the
level of the lubricant in the crankshaft chamber and sufficiently
lubricates the clutch assembly in the clutch chamber by positioning
an overflow opening between the crankshaft chamber and the clutch
chamber to maintain the level of lubricant in the clutch chamber at
a level that is above the level of the lubricant in the crankshaft
chamber.
[0008] The lubrication system decreases the manufacturing costs of
the engine/transmission assembly and reduces the maintenance time
required to maintain the proper fill level of lubricant by
eliminating the need for separate lubricant fill holes and
dipsticks. The proper fill level is obtained by measuring the fill
level of the lubricant in the crankshaft chamber and by supplying
lubricant to the clutch chamber through a single fill hole.
[0009] One embodiment of the present invention is directed to an
engine/transmission assembly that includes a first chamber, a
second chamber, and a fill hole that fluidly communicates with the
first chamber. The first chamber is capable of containing lubricant
at a first level, and the second chamber is capable of containing
lubricant at a second level. The engine/transmission assembly also
includes an opening that is between the first and second chamber
and that fluidly communicates with the first and second chamber.
The opening is positioned to maintain the first level in the first
chamber and raise the second level in the second chamber when
lubricant is added to the first chamber through the fill hole.
[0010] Other features and advantages of the invention will become
apparent to those skilled in the art upon review of the following
detailed description, claims, and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a side view illustrating an engine/transmission
assembly embodying the present invention.
[0012] FIG. 2 is a partial cross section view taken along line 2-2
in FIG. 1, illustrating a chain tower of the engine/transmission
assembly.
[0013] FIG. 3 is a cross section view taken along line 3-3 in FIG.
2, illustrating a clutch chamber of the engine/transmission
assembly.
[0014] FIG. 4 is a partial cross section view taken along line 4-4
in FIG. 1, illustrating an overflow opening and a dipstick of the
engine/transmission assembly.
[0015] FIG. 5 is a partial cross section view taken along line 5-5
in FIG. 1, illustrating a drain hole of the engine/transmission
assembly.
[0016] FIG. 6 is a partial cross section view taken along line 6-6
in FIG. 1, illustrating a fill hole of the engine/transmission
assembly.
[0017] FIG. 7 is a schematic view illustrating the operation of the
engine/transmission assembly shown in FIG. 1.
[0018] Before one embodiment of the invention is explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangements
of the components set forth in the following description or
illustrated in the drawings. The invention is capable of other
embodiments and of being practiced or being carried out in various
ways. Also, it is understood that the phraseology and terminology
used herein is for the purpose of description and should not be
regarded as limiting. The use of "including" and "comprising" and
variations thereof herein is meant to encompass the items listed
thereafter and equivalents thereof as well as additional items. The
use of "consisting of" and variations thereof herein is meant to
encompass only the items listed thereafter. The use of letters to
identify elements of a method or process is simply for
identification and is not meant to indicate that the elements
should be performed in a particular order.
DETAILED DESCRIPTION
[0019] FIG. 1 illustrates an engine/transmission assembly 10 of the
present invention. The engine/transmission assembly 10 includes a
housing 12 and an engine 14 including a cylinder housing 16, a
cylinder head 18, and a cylinder head cover 20.
[0020] In further reference to FIG. 4, the housing 12 includes a
first side 24 that includes an outboard wall 26 and a curved outer
wall 28 that extends from the perimeter of the outboard wall 26 and
that is substantially perpendicular to the outboard wall 26. A
forward portion 30 of the outer wall 28 is configured to partially
define a cylinder bore 32 (FIG. 2). The first side 24 also includes
a lubricant filter cavity 34 that houses a lubricant filter 35
(shown schematically in FIG. 7) which is capable of removing
contaminates from a lubricant 36.
[0021] The housing 12 also includes a second side 38 that includes
an outer wall 40. A forward portion 42 of the outer wall 40 is
configured to partially define the cylinder bore 32 (FIG. 2), and
the outer wall 40 includes a chain cavity 44 (FIGS. 2 and 3).
[0022] The second side 38 also includes a dividing wall 46 that
extends approximately perpendicularly from the outer wall 40 and
that divides the outer wall 40 into first and second portions 48,
50. The dividing wall 46 includes an overflow opening 52, and the
second portion 50 of the outer wall 40 includes a drain hole 54
that is capable of draining a lubricant 36 (FIG. 5).
[0023] The housing 12 also includes a second side cover 56 that has
an outboard wall 58 and an outer wall 60 that extends from the
perimeter of the outboard wall 58 and that is substantially
perpendicular to the outboard wall 58. As shown in FIG. 6, the
outboard wall 58 also includes a lubricant fill hole 62 that opens
substantially upwardly to allow a lubricant 36 to be poured into
the lubricant fill hole 62. The lubricant fill hole 62 includes
internal threads 64 to threadingly engage with external threads 66
on an lubricant fill hole cap 68. The outboard wall 58 also
includes a projection, or sight blocker 70 that extends from the
outboard wall 58. The sight blocker 70 is positioned below the
lubricant fill hole 62 and above lubricant level 198 to obstruct
the view of the lubricant level 198 through the fill hole 62.
[0024] The configuration of the housing 12 is not limited to the
illustrated embodiment and can vary without departing from the
scope of the present invention.
[0025] Referring back to FIG. 4, the outboard wall 58 also includes
a dipstick housing 72 that extends toward the bottom of the
outboard wall 58 and into the outer wall 60 of the second side
cover 56. The dipstick housing 72 includes internal threads 74 that
threadingly engage external threads 76 of a dipstick 78 that
extends through a substantial portion of the dipstick housing
72.
[0026] With specific reference to FIGS. 4 and 5, the second side 38
and the second side cover 56 are fastened together such that a
gasket (not shown) is coupled between an adjacent face 80 of the
outer wall 60 of the second side cover 56 and an adjacent face 82
of the first portion 48 of the outer wall 40 of the second side 38
to form a first, or clutch chamber 84. The clutch chamber 84 is
defined by the outboard wall 58 of the second side cover 56, the
dividing wall 46, the first portion 48, and the outer wall 60 of
the second side cover 56. The clutch chamber 84 is in fluid flow
communication with the drain hole 54, the fill hole 62, the
overflow opening 52, and the chain cavity 44.
[0027] The first side 24 and the second side 38 are fastened
together such that a gasket (not shown) is coupled between an
adjacent face 86 of the outer wall 28 of the first side 24 and an
adjacent face 88 of the second portion 50 of the outer wall 40 of
the second side 38 to form a second, or crankshaft chamber 90. The
crankshaft chamber 90 is defined by the outboard wall 26 of the
first side 24, the dividing wall 46, the second portion 50, and the
outer wall 28 of the first side 24. The crankshaft chamber 90 is in
fluid flow communication with the drain hole 54, the overflow
opening 52, the cylinder bore 32, and the dipstick housing 72
through a passageway 91 that is positioned in the first portion 48
of the outer wall 40 of the second side 38 and adjacent to the
clutch cavity. The drain hole 54 includes internal threads 92 that
are removably threadingly engaged with external threads 94 on a
drain plug 96. When the drain plug 96 is inserted into the drain
hole 54 the drain plug 96 blocks the clutch and crankshaft chamber
84, 90 from being fluidly connected with each other and with the
drain hole 54.
[0028] Referring to FIG. 2, the cylinder housing 16 includes the
cylinder bore 32, cooling fins 102, and the chain cavity 44. The
cylinder bore 32 extends through the cylinder housing 16 along a
bore axis 106, and the cooling fins 102 extend perpendicularly from
the bore axis 106 from top, bottom, and side faces 108, 110, 112 of
the cylinder housing 16 (FIG. 1).
[0029] The cylinder head 18 includes a cam shaft 116, rocker arms
(not shown), intake and exhaust valves (not shown), and a spark
plug 124. The cam shaft 116 is rotatably mounted to the cylinder
head 18 and includes first and second lobes 128. The cam shaft 116
includes a cam sprocket 130 that is positioned within the chain
cavity 44 of the cylinder head 18 and that engages a chain 134. The
rocker arms are pivotably connected to a rocker shaft (not shown)
and slidably engage the lobes 128 of the cam shaft 116. The valves
include stems that engage the rocker arms and valve heads 138 that
are biased against valve seats in the cylinder head 18. The
cylinder head 18 is connected to the cylinder housing 16 such that
the valve heads 138 and the spark plug 124 communicate with a
combustion chamber 142 of the cylinder bore 32.
[0030] The cylinder head cover 20 is connected over the cylinder
head 18 for protection and to prevent the lubricant 36 from
escaping the engine/transmission assembly 10. The cylinder head
cover 20, the cylinder head 18, the cylinder housing 16, and the
housing 12 are connected with elongated bolts (not shown) that
extend from the housing 12 through holes (not shown) located in the
corners of the cylinder housing 16, the cylinder head 18, and the
cylinder head cover 20.
[0031] The engine/transmission assembly 10 as illustrated in FIGS.
4-6 includes a crankshaft 144, a clutch assembly 146, an
intermediate shaft 148, and an output shaft 150. As shown in FIG.
5, the crankshaft 144 is rotatably coupled between the outboard
wall 26 of the first side 24 and the dividing wall 46 of the second
side 38. The crankshaft 144 is substantially positioned within the
crankshaft chamber 90 and includes a crankshaft axis 152. The
crankshaft 144 includes a crank pin 154 that is offset from the
crankshaft axis 152. A connecting rod 158 rotatably connects the
crank pin 154 with a piston 160 that is positioned for reciprocal
motion in the cylinder bore 32 to rotate the crankshaft 144 (FIG.
2). The crankshaft 144 also includes at one end a pump drive gear
162 that drives a pump 163 (shown schematically in FIG. 7) that
distributes lubricant 36 throughout the engine. The other end of
the crankshaft 144 extends through the dividing wall 46 and into
the clutch chamber 84 where it couples to the clutch assembly 146
and a drive sprocket 164 that drives the chain 134 which engages to
the cam sprocket 130.
[0032] The clutch assembly 146 includes an automatic clutch 166
that is connected to the crankshaft 144 and that is rotatably
coupled to the outboard wall 58 of the second side cover 56. The
automatic clutch 166 is positioned within the clutch chamber
84.
[0033] Referring again to FIG. 4, the intermediate shaft 148 is
rotatably coupled to the outboard wall 58 of the second side cover
56 and the outboard wall 26 of the first side 24. The intermediate
shaft 148 extends through the overflow opening 52. The intermediate
shaft 148 includes a first portion 172 positioned within the clutch
chamber 84 and a second portion 174 positioned within the
crankshaft chamber 90. The first portion 172 engages the clutch
assembly 146 and the second portion engages the output shaft
150.
[0034] As shown in FIG. 6, the output shaft 150 is rotatably
coupled to the dividing wall 46 of the second side 38 and the
outboard wall 26 of the first side 24. The output shaft 150 extends
through the outboard wall 26 of the first side 24 and is coupled to
an output sprocket 184 that can engage a drive chain 186 which
could be used to rotate a wheel of a scooter, for example.
[0035] Prior to running the engine, the clutch chamber 84 and the
crankshaft chamber 90 are filled with a lubricant 36 that is used
along with a lubrication system 196 (shown schematically in FIG. 7)
to lubricate the components of the engine/transmission assembly 10.
Initially, the lubricant fill hole cap 68 is removed and the
lubricant 36 is poured into the clutch chamber 84 through the open
fill hole 62. After the clutch chamber 84 is filled up to the level
of the overflow opening 52, the excess lubricant 36 will run
through the overflow opening 52 and into the crankshaft chamber 90
to begin filling the crankshaft chamber 90. The sight blocker 70
prevents the operator from seeing the fill level of the clutch
chamber 84 to ensure that the operator uses the dipstick 78 to
measure the fill level of the lubricant 36. If the sight blocker 70
was not present, an operator might incorrectly conclude that both
chambers 84, 90 are properly filled based on visually confirming
that the clutch chamber 84 is filled.
[0036] The operator uses the dipstick 78 to determine the level of
lubricant 36 in the crankshaft chamber 90 and adds lubricant 36 to
the clutch chamber 84 until the level in the crankshaft chamber 90
is properly within the limits marked on the dipstick 78. When the
lubricant 36 in the crankshaft chamber 90 is within the limits of
the dipstick 78, the lubricant 36 is at the proper fill level. At
the proper fill level, the lubricant 36 in the clutch chamber 84 is
at the first lubricant level 198 such that the automatic clutch 166
is partially submerged in the lubricant 36, and the lubricant 36 in
the crankshaft chamber 90 is at a second level 200 such that the
crankshaft 144 is positioned substantially above the lubricant 36
throughout the rotation of the crankshaft 144. After the proper
fill level is obtained, the lubricant fill cap 68 and dipstick 78
are replaced. The proper fill level as shown in the drawings and as
mentioned in the specification and claims is measured when the
engine 14 is at rest.
[0037] The operation of the lubrication system 196 is described
with reference to FIG. 7. The pump 163, which is driven by the pump
drive gear 162 of the crankshaft 144, pumps lubricant 36 from the
crankshaft chamber 90 and moves the lubricant 36 to the lubricant
filter 35 within the lubricant filter cavity 34. From the lubricant
filter cavity 34 the flow of lubricant 36 is split into a first
portion 202 that is diverted to the crankshaft 144 and a second
larger portion that is diverted to the cylinder head 18.
[0038] The first portion 202 moves through the outboard wall 26 of
the first side 24 to lubricate a bearing 206 of the crankshaft 144
and moves through a hollow passage of the crankshaft 144 to
lubricate between the crank pin 154 and connecting rod 158. The
lubricant 36 then exits the bearing 206 and the crank pin 154 and
falls to accumulate in the crankshaft chamber 90.
[0039] In further reference to FIG. 7, the second portion 204 of
lubricant 36 moves up through the cylinder housing 16 and the
cylinder head 18 by flowing through a clearance between a bolt and
bolt hole. Once the second portion 204 of lubricant 36 reaches the
cylinder head 18, the lubricant 36 escapes the hole to lubricate a
first cam bearing 208 (FIG. 2). The lubricant 36 then enters into a
passageway in the rocker shaft to intermittently lubricate the
rocker arms and cam lobes 128. The lubricant 36 escapes through
holes in the rocker shaft and holes in the rocker arms that align
when the rocker arms are in a specific position relative to the
rocker shaft. The remaining lubricant 36 in the rocker shaft flows
across the rocker shaft to lubricate the second cam bearing (not
shown).
[0040] After the second portion 204 of lubricant 36 is diverted
throughout the cylinder head 18, it collects in the cam/rocker arm
cavity until it overflows into the chain cavity 44 of the cylinder
head 18 and down the chain cavity 44 into the clutch chamber 84
(FIG. 3). The clutch chamber 84 will feed excess lubricant 36 into
the crankshaft chamber 90 through the overflow opening 52, and the
lubricant 36 will therefore be maintained at the proper levels in
the clutch and crankshaft chambers 84, 90.
[0041] Since the overflow opening 52 regulates a constant lubricant
level 198 in the clutch chamber 84, consumed lubricant will affect
the lubricant level 200 only in the crankcase chamber 90 where it
can be measured by dipstick 78.
[0042] The invention is not limited to the illustrated powertrain.
Different clutch assemblies, valve trains, and lubrication paths
can be used without departing from the scope of the present
invention.
* * * * *