U.S. patent application number 16/039899 was filed with the patent office on 2020-01-23 for sprocket gerotor pump.
This patent application is currently assigned to GM Global Technology Operations LLC. The applicant listed for this patent is GM Global Technology Operations LLC. Invention is credited to Andy Bennett, SR., Sean M. McGowan.
Application Number | 20200025198 16/039899 |
Document ID | / |
Family ID | 69147906 |
Filed Date | 2020-01-23 |
United States Patent
Application |
20200025198 |
Kind Code |
A1 |
Bennett, SR.; Andy ; et
al. |
January 23, 2020 |
SPROCKET GEROTOR PUMP
Abstract
A sprocket gerotor pump includes an outer gerotor gear
configured to rotate about a first axis. The outer gerotor gear
includes an outer gear body including a plurality of internal gear
teeth extending from the outer gear body toward the first axis. The
sprocket gerotor pump includes an inner gerotor gear configured to
rotate about a second axis. The inner gerotor gear includes an
inner gear body and a plurality of external gear teeth extending
from the inner gerotor gear away from the second axis. The external
gear teeth mesh with the internal gear teeth. Rotating the outer
gerotor gear causes rotation of the inner gerotor gear. The
sprocket gerotor pump further includes a sprocket integrally
coupled with the outer gerotor gear such that the sprocket and the
outer gerotor gear collectively form a one-piece structure. The
sprocket is driven by a chain.
Inventors: |
Bennett, SR.; Andy;
(Rochester Hills, MI) ; McGowan; Sean M.;
(Northville, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GM Global Technology Operations LLC |
Detroit |
MI |
US |
|
|
Assignee: |
GM Global Technology Operations
LLC
Detroit
MI
|
Family ID: |
69147906 |
Appl. No.: |
16/039899 |
Filed: |
July 19, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04C 2240/20 20130101;
F04C 2/102 20130101; F01M 2001/0238 20130101; F01M 2001/0253
20130101; F04C 2210/206 20130101; F04C 2/084 20130101; F04C 15/0061
20130101; F04C 2210/14 20130101; F16N 13/20 20130101; F01M 1/02
20130101 |
International
Class: |
F04C 15/00 20060101
F04C015/00; F04C 2/10 20060101 F04C002/10; F04C 2/08 20060101
F04C002/08 |
Claims
1. A sprocket gerotor pump, comprising: an outer gerotor gear
configured to rotate about a first axis, wherein the outer gerotor
gear includes an outer gear body including a plurality of internal
gear teeth extending from the outer gear body toward the first
axis; an inner gerotor gear configured to rotate about a second
axis, wherein the second axis is spaced apart from the first axis,
the inner gerotor gear includes an inner gear body and a plurality
of external gear teeth extending from the inner gear body away from
the second axis, and the plurality of external gear teeth meshes
with the plurality of the internal gear teeth such that rotation of
the outer gerotor gear causes rotation of the inner gerotor gear;
and a sprocket integrally coupled with the outer gerotor gear such
that the sprocket and the outer gerotor gear collectively form a
one-piece structure.
2. The sprocket gerotor pump of claim 1, wherein the sprocket
includes a ring and a plurality of external sprocket teeth
extending from the ring.
3. The sprocket gerotor pump of claim 2, wherein the ring is
directly coupled to the outer gear body, the first axis is parallel
to the second axis, and each of the plurality of external sprocket
teeth is directly coupled to the ring.
4. The sprocket gerotor pump of claim 3, wherein the plurality of
internal gear teeth defines an inner cavity, the inner cavity is
sized to receive the inner gerotor gear, and the inner gerotor gear
is entirely disposed inside the inner cavity.
5. The sprocket gerotor pump of claim 4, further comprising a
housing partially encasing the outer gerotor gear.
6. The sprocket gerotor pump of claim 5, further comprising a cover
partially encasing the outer gerotor gear.
7. The sprocket gerotor pump of claim 6, wherein the housing and
the cover collectively define an annular gap therebetween.
8. The sprocket gerotor pump of claim 7, wherein the annular gap is
sized to receive the plurality of external sprocket teeth.
9. The sprocket gerotor pump of claim 8, further comprising a chain
meshed with the plurality of external sprocket teeth.
10. The sprocket gerotor pump of claim 9, wherein the annular gap
receives the plurality of external sprocket teeth and a portion of
the chain.
11. A vehicle system, comprising: an engine block; a sprocket
gerotor pump supported by the engine block, wherein the sprocket
gerotor pump includes: an outer gerotor gear configured to rotate
about a first axis, wherein the outer gerotor gear includes an
outer gear body including a plurality of internal gear teeth
extending from the outer gear body toward the first axis; an inner
gerotor gear configured to rotate about a second axis, wherein the
first axis is parallel to the second axis, the second axis is
spaced apart from the first axis, the inner gerotor gear includes
an inner gear body and a plurality of external gear teeth extending
from the inner gear body away from the second axis, and the
plurality of external gear teeth meshes with the plurality of the
internal gear teeth such that rotation of the outer gerotor gear
causes rotation of the inner gerotor gear, the plurality of
internal gear teeth defines an inner cavity, the inner cavity is
sized to receive the inner gerotor gear, and the inner gerotor gear
is entirely disposed inside the inner cavity; and a sprocket
integrally coupled with the outer gerotor gear such that the
sprocket and the outer gerotor gear collectively form a one-piece
structure.
12. The vehicle system of claim 11, wherein the sprocket includes a
ring and a plurality of external sprocket teeth extending from the
ring.
13. The vehicle system of claim 12, wherein the ring is directly
coupled to the outer gear body, the first axis is parallel to the
second axis, and each of the plurality of external sprocket teeth
is directly coupled to the ring.
14. The vehicle system of claim 13, wherein the plurality of
internal gear teeth defines an inner cavity, the inner cavity is
sized to receive the inner gerotor gear, and the inner gerotor gear
is entirely disposed inside the inner cavity.
15. The vehicle system of claim 14, further comprising a housing
partially encasing the outer gerotor gear.
16. The vehicle system of claim 15, further comprising a cover
partially encasing the outer gerotor gear.
17. The vehicle system of claim 16, wherein the housing and the
cover collectively define an annular gap therebetween.
18. The vehicle system of claim 17, wherein the annular gap is
sized to receive the plurality of external sprocket teeth.
19. The vehicle system of claim 18, further comprising a chain
meshed with the plurality of external sprocket teeth, the annular
gap receives the plurality of external sprocket teeth and a portion
of the chain.
20. A vehicle system, comprising: an internal combustion engine
including an engine block; and a sprocket gerotor pump supported by
the engine block, wherein the engine block is in direct contact
with the sprocket gerotor pump and includes: an outer gerotor gear
configured to rotate about a first axis, wherein the outer gerotor
gear includes an outer gear body including a plurality of internal
gear teeth extending from the outer gear body toward the first
axis; an inner gerotor gear configured to rotate about a second
axis, wherein the first axis is parallel to the second axis, the
second axis is spaced apart from the first axis, the inner gerotor
gear includes an inner gear body and a plurality of external gear
teeth extending from the inner gear body away from the second axis,
and the plurality of external gear teeth meshes with the plurality
of the internal gear teeth such that rotation of the outer gerotor
gear causes rotation of the inner gerotor gear; a sprocket
integrally coupled with the outer gerotor gear such that the
sprocket and the outer gerotor gear collectively form a one-piece
structure, wherein the sprocket includes a ring and a plurality of
external sprocket teeth extending from the ring, the ring is
directly coupled to the outer gear body, and each of the plurality
of external sprocket teeth is directly coupled to the ring, each of
the plurality of external sprocket teeth extend away from the first
axis; a housing partially encasing the outer gerotor gear; a cover
partially encasing the outer gerotor gear, wherein the housing and
the cover collectively define an annular gap therebetween; and a
chain meshed with the plurality of external sprocket teeth, wherein
the annular gap solely receives the plurality of external sprocket
teeth and a portion of the chain.
Description
INTRODUCTION
[0001] The present disclosure relates to a sprocket gerotor pump.
Specifically, the present disclosure describes a gerotor pump
integrated with a sprocket.
[0002] Vehicle systems may include pumps for supplying lubricant to
one or more vehicle components. These pumps have to be accommodated
within the vehicle systems. It is therefore desirable to develop a
pump with minimal package size.
SUMMARY
[0003] The present disclosure describes a gerotor pump that
integrates a sprocket. By integrally coupling the sprocket to the
outer gerotor gear, the package size and the mass of the sprocket
gerotor pump is minimized. The sprocket gerotor pump may serve as a
supply pump or a scavenge pump. In some embodiments, the sprocket
gerotor pump may be part of a vehicle system. The vehicle system
may include an internal combustion engine having an engine block.
The sprocket gerotor pump is supported by the engine block. For
instance, the engine block may be in direct contact with the
sprocket gerotor pump. The sprocket gerotor pump includes an outer
gerotor gear configured to rotate about a first axis. The outer
gerotor gear includes an outer gear body including a plurality of
internal gear teeth extending from the outer gear body toward the
first axis. The sprocket gerotor pump includes an inner gerotor
gear configured to rotate about a second axis. The first axis is
parallel to the second axis. The second axis is spaced apart from
the first axis. The inner gerotor gear includes an inner gear body
and a plurality of external gear teeth extending from the inner
gear body away from the second axis. The plurality of external gear
teeth meshes with the plurality of the internal gear teeth such
that rotation of the outer gerotor gear causes rotation of the
inner gerotor gear. The sprocket gerotor pump includes a sprocket
integrally coupled with the outer gerotor gear such that the
sprocket and the outer gerotor gear collectively form a one-piece
structure. The sprocket includes a ring and a plurality of external
sprocket teeth extending from the ring. The ring is directly
coupled to the outer gear body. Each of the plurality of external
sprocket teeth is directly coupled to the ring. Each of the
plurality of external sprocket teeth extend away from the first
axis. The sprocket gerotor pump includes a housing partially
encasing the outer gerotor gear. The sprocket gerotor pump includes
a cover partially encasing the outer gerotor gear. The housing and
the cover collectively define an annular gap therebetween. The
sprocket gerotor pump includes a chain meshed with the plurality of
external sprocket teeth. The annular gap solely receives the
plurality of external sprocket teeth and a portion of the
chain.
[0004] The above features and advantages and other features and
advantages of the present disclosure are readily apparent from the
following detailed description of the best modes for carrying out
the disclosure when taken in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a schematic illustration of a vehicle including an
internal combustion engine, a lubricant source, and a sprocket
gerotor pump in fluid communication with the lubricant source and
the internal combustion engine, wherein the sprocket gerotor pump
may be a supply pump or a scavenge pump.
[0006] FIG. 2 is a schematic perspective sectional view of an
engine block and the sprocket gerotor pump of FIG. 1.
[0007] FIG. 3 is a schematic front view of the engine block and the
sprocket gerotor pump of FIG. 1.
[0008] FIG. 4 is a schematic side view of the sprocket gerotor pump
of FIG. 1.
[0009] FIG. 5 is a schematic perspective, exploded view of the
gerotor of FIG. 1.
[0010] FIG. 6 is a schematic perspective, exploded view of a
housing, a cover, an outer gerotor gear, a shaft, and an inner
gerotor gear of the sprocket gerotor pump of FIG. 1.
[0011] FIG. 7 is a schematic sectional side view of the sprocket
gerotor pump o FIG. 1.
DETAILED DESCRIPTION
[0012] With reference to FIG. 1, a vehicle system 10 includes a
sprocket gerotor pump 12. The sprocket gerotor pump 12 may be
configured as a supply pump 12 for moving a lubricant L (i.e., oil)
to a vehicle component 13 and/or as a scavenge pump 12b for
returning the lubricant L back to a lubricant source 16 (e.g., a
storage reservoir). The vehicle system 10 may be a car, a truck, or
other suitable device capable of transporting objects or
passengers. In the depicted embodiment, the vehicle component 13
may be an internal combustion engine 14 having an engine block 18.
Therefore, the sprocket gerotor pump 12 is in fluid communication
with the vehicle component 13 (e.g., the internal combustion engine
14). The sprocket gerotor pump 12 is also in fluid communication
with the lubricant source 16 (e.g., reservoir) containing the
lubricant L (e.g., oil). Accordingly, the sprocket gerotor pump 12
may pump lubricant L from the lubricant source 16 to the vehicle
component 13 (e.g., the internal combustion engine 14).
Alternatively, the sprocket gerotor pump 12 may return from the
vehicle component 13 back to the lubricant source 16.
[0013] With reference to FIGS. 2 and 4, one or more fasteners 20
directly connects the sprocket gerotor pump 12 to the engine block
18. In the depicted embodiment, the fasteners 20 are bolts 22
extending through the sprocket gerotor pump 12 and into the engine
block 18 in order to directly couple the sprocket gerotor pump 12
to the engine block 18. Plastic bolt retainers 24 may be attached
to each bolt 22 for retaining the bolts 22 in a fixed shipping
position. The sprocket gerotor pump 12 is also supported by the
engine block 18. For example, the engine block 18 may be in direct
contact with the sprocket gerotor pump 12 to enhance their
structural connection.
[0014] With reference to FIGS. 2-7, the sprocket gerotor pump 12 is
a positive displacement pump including a pickup tube 26 in fluid
communication with the lubricant in the engine cylinder head
cavities. The pickup tube 26 defines a pickup channel 28 (FIG. 5)
for allowing fluid flow of the lubricant L. An O-ring may be
disposed around an annular portion 30 of the pickup tube 26 to
avoid air suction. The sprocket gerotor pump 12 further includes an
outer gerotor gear 34 and a housing 32 partially encasing the outer
gerotor gear 34. One or more fasteners 20 (e.g., bolts 22) directly
couples pickup tube 26 to the housing 32. The housing 32 further
includes a housing body 40, a first housing flange 42 extending
laterally from the housing body 40, and a second housing flange 44
extending laterally from the housing body 40. The housing 32
defines a first flange hole 46 extending through the first housing
flange 42 and a second flange hole 48 extending through the second
housing flange 44. Each of the first flange hole 46 and the second
flange hole 48 is configured, sized, and shaped to receive one of
the fasteners 20 (e.g., bolts 22).
[0015] As discussed above, the sprocket gerotor pump 12 includes
the outer gerotor gear 34. Aside from being configured to rotate
about the first axis X1, the outer gerotor gear 34 includes an
outer gear body 36 including a plurality of internal gear teeth 38
extending from the outer gear body 36 toward the first axis X1.
[0016] The sprocket gerotor pump 12 further includes an inner
gerotor gear 50 configured to rotate about a second axis X2. The
first axis X1 of the outer gerotor gear 34 is spaced apart (and
parallel to) the second axis X2 of the inner gerotor gear 50. In
other words, the second axis X2 is offset from the first axis X1.
The inner gerotor gear 50 includes an inner gear body 52 and a
plurality of external gear teeth 54 extending from the inner gear
body 52 away from the second axis X2. The external gear teeth 54
mesh with the internal gear teeth 38 of the outer gerotor gear 34.
Consequently, rotating the outer gerotor gear 34 causes rotation of
the inner gerotor gear 50. The internal gear teeth 38 defines an
inner cavity 53. The inner cavity 53 is sized to receive the inner
gerotor gear 50. Specifically, the inner gerotor gear 50 is
entirely disposed inside the inner cavity 53. The inner gerotor
gear 50 has n external gear teeth 54, while the outer gerotor gear
34 has n+1 internal gear teeth 38, wherein n is a natural number
greater than 2. The geometry of the inner gerotor gear 50 and the
outer gerotor gear 34 partitions the volume between them into n
different dynamically-changing volumes. During rotation, each of
these volumes defined between the internal gear teeth 38 and the
external gear teeth 54 changes continuously (i.e., increasing and
then decreasing). An increase in volume creates a vacuum. This
vacuum in turn creates suction. Lubricant intake by the sprocket
gerotor pump 12 occurs during suction. On the other hand, cavity
compression occurs when the volume between the internal gear teeth
38 and the external gear teeth 54 decreases. During cavity 53
compression, the lubricant L is squeezed out of the sprocket
gerotor pump 12.
[0017] The sprocket gerotor pump 12 further includes a sprocket 56
integrally coupled with the outer gerotor gear 34. As such, the
sprocket 56 and the outer gerotor gear 34 collectively form a
one-piece structure. The term "integrally coupled" means that
components are part of a one-piece or unitary structure and
excludes components that are interconnected by, for example,
fasteners, welding, friction fitting, adhesives, or other attaching
methods. The term "one-piece structure" means a structure made of a
single undivided piece and excludes structures made of components
that are interconnected by, for example, fasteners, welding,
friction fitting, adhesives, or other attaching methods. By
integrally coupling the sprocket 56 to the outer gerotor gear 34,
the package size and the mass of the sprocket gerotor pump 12 is
minimized. As a result, the additional package space is created in
the vehicle system 10, allowing vehicle manufacturers to
incorporate additional devices into the vehicle system 10. The
sprocket 56 includes a ring 58 and a plurality of external sprocket
teeth 60 extending from the ring 58. The ring 58 is directly
coupled to the outer gear body 36. Specifically, the ring 58 is
integrally coupled to the outer gear body 36 to minimize the
package size of the sprocket gerotor pump 12 as discussed above.
Each of the external sprocket teeth 60 is directly coupled to the
ring 58. Specifically, each of the external sprocket teeth 60 is
integrally coupled to the ring 58 to minimize the package size of
the sprocket gerotor pump 12 as discussed above. Each of the
external sprocket teeth 60 extends away from the first axis X1.
[0018] The sprocket gerotor pump 12 further includes a cover 62
partially encasing the outer gerotor gear 34. The housing 32 and
the cover 62 collectively define an annular gap 64 therebetween.
The sprocket gerotor pump 12 further includes a chain 66 partially
disposed in the annular gap 64. One or more fasteners 20 (e.g.,
bolts 22) couple the cover 62 to the housing 32 while maintaining
the annular gap 64 between the cover 62 and the housing 32. In the
case of the supply pump 12a, the cover 62 defines an outlet 70 to
deliver lubricant L to the vehicle component 13. In the case of the
scavenge pump 12b, the cover 62 defines an outlet 70 to deliver
lubricant L to the lubricant source 16. One or more seals 72 are
coupled to the outlet 70 to minimize lubricant leakage. Another
sprocket (that is not part of the meshed sprocket gerotor pump 12)
is connected to a crankshaft and drives the chain 66 to rotate the
outer gerotor gear 34. The chain 66 meshes with the external
sprocket teeth 60. Thus, rotating the chain 66 causes the outer
gerotor gear 34 to rotate. The annular gap 64 solely receives the
external sprocket teeth 60 and a portion of the chain 66 to
minimize the space occupied by the sprocket gerotor pump 12. A
chain tensioner 68 may be coupled to the engine block 18 to
maintain the chain 66 in tension. Accordingly, the chain tensioner
68 is configured to be in direct contact with the chain 66. The
housing 62 includes a support feature 63 (e.g., protrusion) that is
on the same plane with other two bases to support the housing 40 to
absorb vibration and structural load.
[0019] The sprocket gerotor pump 12 further includes a shaft 74
extending through the cover 62, the housing 32, and the inner
gerotor gear 50. Accordingly, the shaft 74 interconnects and
supports the cover 62, the housing 32, and the inner gerotor gear
50. The shaft 74 includes a first end portion 76 (FIG. 7) and a
second end portion 78 (FIG. 8) spaced apart from the first end
portion 76 along the second axis X2. Further, the shaft 74 includes
a thrust face/bearing face 80. The shaft flange 80 is closer to the
first end portion 76 than to the second end portion 78 of the shaft
74. The sprocket gerotor pump 12 includes a first bushing 82 and a
second bushing 84. The first bushing 82 is coupled to the first end
portion 76, and the second bushing 84 is coupled to the second end
portion 78 of the shaft 74. The chain 66 is located in the annular
gap 64 between the first bushing 82 and the second bushing 84 to
evenly distribute the load exerted by the chain 66, thereby
maximizing shared stress load on the shaft 74 and the bearings 84
and 76.
[0020] While the best modes for carrying out the disclosure have
been described in detail, those familiar with the art to which this
disclosure relates will recognize various alternative designs and
embodiments for practicing the disclosure within the scope of the
appended claims.
* * * * *