U.S. patent application number 17/553026 was filed with the patent office on 2022-09-29 for scavenging pump.
The applicant listed for this patent is YAMADA MANUFACTURING CO., LTD.. Invention is credited to Masahiko Fujii, Yuu Hirayama, Atsushi Kaneko, Kenji Kawashima, Masako Masuda.
Application Number | 20220307393 17/553026 |
Document ID | / |
Family ID | 1000006125719 |
Filed Date | 2022-09-29 |
United States Patent
Application |
20220307393 |
Kind Code |
A1 |
Fujii; Masahiko ; et
al. |
September 29, 2022 |
SCAVENGING PUMP
Abstract
A scavenging pump is utilized to draw oils from a catch tank
that collects the oils supplied to components to an oil pan that
reserves therein the oils. The scavenging pump includes gears to
draw the oils, and a housing that stores therein the gears. An oil
receiving portion capable of receiving the oils injected from the
exterior is formed in an outer circumferential surface of the
housing, and an oil introducing hole that introduces the oils
injected to the oil receiving portion into the interior is opened
at a position continuous from a lower part of the oil receiving
portion and facing the gears.
Inventors: |
Fujii; Masahiko; (Kiryu-shi,
JP) ; Hirayama; Yuu; (Kiryu-shi, JP) ;
Kawashima; Kenji; (Kiryu-shi, JP) ; Masuda;
Masako; (Kiryu-shi, JP) ; Kaneko; Atsushi;
(Kiryu-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
YAMADA MANUFACTURING CO., LTD. |
Kiryu-shi |
|
JP |
|
|
Family ID: |
1000006125719 |
Appl. No.: |
17/553026 |
Filed: |
December 16, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01M 1/02 20130101; F01M
2011/0095 20130101; F01M 2001/0238 20130101 |
International
Class: |
F01M 1/02 20060101
F01M001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 26, 2021 |
JP |
2021-52941 |
Claims
1. A scavenging pump utilized to draw oils from a catch tank that
collects the oils supplied to a component to an oil pan that
reserves therein the oils, and comprising: gears to draw the oils;
and a housing that stores therein the gears, wherein an oil
receiving portion capable of receiving the oils injected from an
exterior is formed in an outer circumferential surface of the
housing, and an oil introducing hole that introduces the oils
injected to the oil receiving portion into an interior is opened at
a position continuous from a lower part of the oil receiving
portion and facing the gears.
2. The scavenging pump according to claim 1, wherein a guide
portion that guides the oils to the oil introducing hole is formed
along an edge of the oil introducing hole at an
outer-circumferential-surface side thereof.
3. The scavenging pump according to claim 1, wherein an area of the
oil receiving portion is larger than an area of the oil introducing
hole.
4. The scavenging pump according to claim 2, wherein the housing
comprises an oil retaining portion which is capable of retaining
the oils together with the guide portion at a circumferential edge
of the oil introducing hole.
5. The scavenging pump according to claim 1, wherein the oil
introducing hole increases a diameter from an outer circumferential
surface to an inner circumferential surface.
6. The scavenging pump according to claim 1, wherein the oil
receiving portion gradually reduces a width toward the oil
introducing hole.
7. The scavenging pump according to claim 1, wherein: a guide
portion that guides the oils to the oil introducing hole is formed
along an edge of the oil introducing hole at an
outer-circumferential-surface side thereof; and an area of the oil
receiving portion is larger than an area of the oil introducing
hole.
8. The scavenging pump according to claim 1, wherein: a guide
portion that guides the oils to the oil introducing hole is formed
along an edge of the oil introducing hole at an
outer-circumferential-surface side thereof; and the oil introducing
hole increases a diameter from an outer circumferential surface to
an inner circumferential surface.
9. The scavenging pump according to claim 1, wherein: an area of
the oil receiving portion is larger than an area of the oil
introducing hole; and the oil introducing hole increases a diameter
from an outer circumferential surface to an inner circumferential
surface.
10. The scavenging pump according to claim 1, wherein: the housing
comprises an oil retaining portion which is capable of retaining
the oils together with the guide portion at a circumferential edge
of the oil introducing hole; and the oil introducing hole increases
a diameter from an outer circumferential surface to an inner
circumferential surface.
11. The scavenging pump according to claim 1, wherein: a guide
portion that guides the oils to the oil introducing hole is formed
along an edge of the oil introducing hole at an
outer-circumferential-surface side thereof; and the oil receiving
portion gradually reduces a width toward the oil introducing
hole.
12. The scavenging pump according to claim 1, wherein: an area of
the oil receiving portion is larger than an area of the oil
introducing hole; and the oil receiving portion gradually reduces a
width toward the oil introducing hole.
13. The scavenging pump according to claim 1, wherein: the housing
comprises an oil retaining portion which is capable of retaining
the oils together with the guide portion at a circumferential edge
of the oil introducing hole; and the oil receiving portion
gradually reduces a width toward the oil introducing hole.
14. The scavenging pump according to claim 1, wherein: the oil
introducing hole increases a diameter from an outer circumferential
surface to an inner circumferential surface; and the oil receiving
portion gradually reduces a width toward the oil introducing hole.
Description
FIELD OF THE INVENTION
[0001] The present disclosure relates to a scavenging pump that
draws oils from a catch tank which collects the oils supplied to
components to an oil pan which reserves therein the oils.
BACKGROUND
[0002] Some vehicles are provided with components, such as a
turbocharger. Such components are allowed to operate and are cooled
by lubrication oils that circulate within a vehicle. Oils that pass
through a component are collected by a catch tank, and are returned
to an oil pan from the catch tank. At this time, when the catch
tank is located at a lower site than that of the catch tank, oils
are drawn from the catch tank to the oil pan using a scavenging
pump. JP 2019-78190 A discloses a conventional technology related
to such a scavenging pump.
[0003] JP 2019-78190 A describes the features of a scavenging pump
by a comparison with a feed pump for circulating oils. One of such
features is that, although a feed pump carries substantially oils
only, a scavenging pump carries not only oils but also air.
SUMMARY OF THE INVENTION
[0004] For example, immediately after the start-up of a vehicle,
sufficient oils are not circulated in a scavenging pump, and oils
are hardly filled therein in some cases. Even if the scavenging
pump is operated in such a state, a large amount of air is present
between gears for drawing the oils. When the oils filled in the
scavenging pump are insufficient, a sealing performance decreases,
making it difficult for such a pump to draw the sufficient amount
of oil. Hence, there is a leeway for an improvement in view of an
efficient circulation of oils.
[0005] An objective of the present disclosure is to provide a
scavenging pump that can efficiently circulate oils.
[0006] According to the present disclosure, a scavenging pump is
provided which is utilized to draw oils from a catch tank that
collects the oils supplied to a component to an oil pan that
reserves therein the oils, and which includes: [0007] gears to draw
the oils; and [0008] a housing that stores therein the gears,
[0009] in which an oil receiving portion capable of receiving the
oils injected from an exterior is formed in an outer
circumferential surface of the housing, and an oil introducing hole
that introduces the oils injected to the oil receiving portion into
an interior is opened at a position continuous from a lower part of
the oil receiving portion and facing the gears.
[0010] According to the present disclosure, a scavenging pump that
can efficiently circulate oils is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is an exemplary diagram of an oil circulating device
that utilizes a scavenging pump according to an embodiment of the
present disclosure;
[0012] FIG. 2 is a perspective view of the scavenging pump
illustrated in FIG. 1;
[0013] FIG. 3 is an exploded view of the scavenging pump
illustrated in FIG. 2;
[0014] FIG. 4A is a diagram for describing an action of a
scavenging pump according to a comparative example; and
[0015] FIG. 4B is a diagram for describing an action of the
scavenging pump according to the embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0016] Embodiments of the present disclosure will be described
below with reference to the accompanying figures. Note that "Up"
and "Dn" in the figure indicate an upper side and a down side,
respectively.
[0017] [Embodiment]
[0018] With reference to FIG. 1, for example, a vehicle is provided
with an oil circulating device 10 for circulating oils. A
scavenging pump 20 according to the present disclosure forms a part
of the oil circulating device 10.
[0019] The oil circulating device 10 includes an oil pan 11 that
reserves therein oils Oi, a feed pump 12 that can draw the oils Oi
from the oil pan 11, a catch tank 14 that collects the oils Oi
which are fed to a turbocharger 13 from the feed pump 12, and which
cool the turbocharger 13, a scavenging pump 20 that draws the oils
Oi from the catch tank 14 to the oil pan 11, and a nozzle 16 that
can inject the oils Oi to the scavenging pump 20.
[0020] The flow channel of the oil circulating device 10 is
branched in order to lubricate other various components to operate
and to cool those in addition to the turbocharger 13. The oils Oi
that pass through the other components are also returned to the oil
pan 11.
[0021] In this example, the components which are lubricated by the
oils Oi to operate and are cooled are, in addition to the engine,
the turbocharger 13, a supercharger, etc. In this embodiment, a
description will be given of a case in which the example component
which is lubricated by the oils to operate and which is cooled is
the turbocharger 13. The turbocharger 13 will be also referred to
as a "component 13".
[0022] With reference to FIG. 2, the nozzle 16 is provided so as to
face the scavenging pump 20. When, for example, the scavenging pump
20 is operated, the oils Oi are injected to the scavenging pump 20
from the nozzle 16. The reason will be described later.
[0023] With reference to also FIG. 3, the scavenging pump 20
includes an inner rotor 22 provided so as to be rotatable, an outer
rotor 23 which surrounds the inner rotor 22, and which rotates
together with the rotation of the inner rotor 22, and a housing 30
that stores therein those rotors.
[0024] The housing 30 includes a main body 31 that stores therein
the inner rotor 22 and the outer rotor 23, and a cover 32 that is
laid over on the main body 31.
[0025] The main body 31 is provided with an inlet hole 31a that is
opened so as to let the oils to enter from the exterior, an inlet
port 31b that guides the oils from the inlet hole 31a to the inner
rotor 22 and to the outer rotor 23, a discharge port 31c to which
the oils guided from the inlet port 31b is delivered, and a
discharge hole 31d that is opened so as to discharge, to the
exterior, the oils delivered to the discharge port 31c.
[0026] An oil receiving portion 32b that can receive the oils
injected from the nozzle 16 is formed in the outer circumferential
surface of the cover 32 so as to be concaved toward the side face
of the inner rotor 22 and that of the outer rotor 23 relative to a
general surface 32a. Moreover, an oil introducing hole 32c that is
continuous from the lower part of the oil receiving portion 32b is
opened at a position that overlaps a boundary between the inner
rotor 22 and the outer rotor 23.
[0027] The general surface 32a and the oil receiving portion 32b
are connected by a guide portion 32d that guides the oils Oi to the
oil introducing hole 32c. The guide portion 32d is continuously
formed along the outer circumference of the oil receiving portion
32b, and the edge of the oil introducing hole 32c.
[0028] The oil receiving portion 32b is formed in such a way that
the width gradually decreases toward the oil introducing hole 32c
formed at the down side. Moreover, the length of the oil receiving
portion 32b in the vertical direction is longer than the diameter
of the oil introducing hole 32c formed in a cylindrical shape. The
area of the oil receiving portion 32b is larger than the area of
the oil introducing hole 32c.
[0029] The oil introducing hole 32c is opened so as to introduce
the injected oils Oi to the oil receiving portion 32b into the
interior of the housing 30. The oil introducing hole 32c is formed
at a position that overlaps a boundary between the inner rotor 22
and the outer rotor 23.
[0030] With reference to FIG. 4B, for example, the oil introducing
hole 32c increases the diameter toward the inner circumferential
surface from the outer circumferential surface. That is, the
diameter of the oil introducing hole 32c is large at the
inner-circumferential-surface side relative to the
outer-circumferential side.
[0031] Note that the position in which the oil introducing hole 32c
is formed may be located above the boundary between the inner rotor
22 and the outer rotor 23.
[0032] Moreover, the oil introducing hole 32c may have the uniform
diameter from the outer-circumferential-surface side to the
inner-circumferential-surface side. Furthermore, the oil
introducing hole 32c may have the uniform diameter from the
inner-circumferential-surface side to the
outer-circumferential-surface side, and inclined downwardly toward
the inner circumferential surface.
[0033] An oil retaining portion 32e that retains therein the oils
Oi is provided under the oil introducing hole 32 together with the
guide portion 32d and along the lower part of the guide portion
32d. The oil retaining portion 32e is formed in a substantially
semi-circular shape along the edge of a lower-half circumference of
the oil guide portion 32d. It is preferable that the upper surface
of the oil retaining portion 32e should be located higher than the
lower edge of the oil introducing hole 32c at the outer-surface
side.
[0034] Note that the oil retaining portion 32e may be formed
integrally with the general surface 32a, not as a separate
component.
[0035] A bar-shape shaft member passes completely through the
center of the inner rotor 22. The shaft member is coupled to, for
example, the crankshaft of an engine. In this case, when the engine
runs, the crankshaft rotates, and the inner rotor 22 also rotates.
The outer rotor 23 placed at the outer-circumference side of the
inner rotor 22 rotates when the inner rotor 22 rotates.
[0036] Note that the inner rotor 22 and the outer rotor 23 are
gears that draw the oils by rotation. In the following description,
the inner rotor 22 and the outer rotor 23 may be collectively
referred to as "gears 22 and 23".
[0037] With reference to FIG. 1 and FIG. 3, when the gears 22 and
23 rotate, the oils Oi are drawn from the catch tank 14. The drawn
oil Oi flow to the inlet port 31b from the inlet hole 31a. The oils
Oi are suctioned in a space surrounded by the inner rotor 22 and
the outer rotor 23 from the inlet port 31b. The suctioned oils Oi
are discharged to the discharge port 31c since the space surrounded
by the inner rotor 22 and the outer rotor 23 becomes small. The
discharged oils Oi to the discharge port 31c are discharged to the
exterior of the housing 30 from the discharge hole 31d, and are
returned to the oil pan 11.
[0038] Meanwhile, immediately after the vehicle starts, the
sufficient oils Oi are not circulated yet, and the substantially
all oils Oi in the scavenging pump 20 are fallen, and thus the
sealing performance of the scavenging pump 20 is insufficient in
some cases. Even if the scavenging pump 20 is operated from such a
state, a large amount of air is present between the inner rotor 22
and the outer rotor 23. Since the force that draws the oils Oi is
weak when the sealing performance between the inner rotor 22 and
the outer rotor 23 is low, and thus it is difficult to circulate
the sufficient amount of the oils Oi. Hence, the oils Oi are
injected from the nozzle 16, and the oils Oi are supplied to the
interior of the housing 30. By supplying the injected oils Oi to
the interior of the housing 30, the sealing performance between the
inner rotor 22 and the outer rotor 23 can be enhanced. Accordingly,
the sufficient oils Oi reserved in the catch tank 14 can be drawn.
That is, the injected oils Oi from the nozzle 16 serve as priming
oils.
[0039] The nozzle 16 starts injecting the oils immediately after
the engine runs, or with a time lag that is several seconds. As far
as the engine keeps running, the injection of the oils Oi from the
nozzle 16 is maintained. At this time, the pressure of the oils
injected from the nozzle 16 changes in accordance with the engine
revolution speed. When the engine revolution speed is fast, the
oils are injected at high pressure.
[0040] The scavenging pump 20 as described above can be summarized
as follows.
[0041] The scavenging pump 20 is utilized to draw the oils Oi from
the catch tank 14 that collects the oils Oi supplied to the
component 13 to the oil pan 11 that reserves therein the oils Oi.
Moreover, the scavenging pump 20 includes the gears 22 and 23 to
draw the oils Oi, and the housing 30 that stores therein these
gears 22 and 23. The housing 30 has the oil receiving portion 32b
which can receive the oils Oi injected from the exterior and which
is formed in the outer circumferential surface, and has the oil
introducing hole 32c which is continuous from the lower part of the
oil receiving portion 32b, is to introduce the injected oils Oi to
the oil receiving portion 32b to the interior and is opened at a
position facing the gears 22 and 23.
[0042] Since the oil introducing hole 32c is opened in the housing
30, the injected oils Oi toward the housing 30 from the exterior
can be introduced therein. Some oils Oi introduced in the housing
30 flow through between the gears 22 and 23, and thus the sealing
performance between the gears 22 and 23 is enhanced. This makes it
possible for the scavenging pump to efficiently draw the oils Oi.
That is, the scavenging pump 20 can efficiently circulate the oils
Oi.
[0043] The reason why the oil receiving portion 32b is formed in
the housing 30 will now be described.
[0044] With reference to FIG. 4A, the inventors of the present
disclosure first created a scavenging pump 120 that had only an oil
introducing hole 132c formed in a housing 130. Such a scavenging
pump 120 was able to efficiently circulate oils, but there is a
leeway for an improvement regarding the efficient oil circulation.
Based on keen examinations, the inventors of the present disclosure
found that since the oils Oi injected from a nozzle 116 is directly
injected to gears 122 and 123, the gears 122 and 123 are slightly
displaced, and the flow volume for drawing the oils decreases.
Moreover, even if the oils Oi do not directly contact the gears 122
and 123, the discharging side flow channel of the discharge hole
31d is clogged by the pressure of the injected oils Oi, and thus it
becomes a state in which the oils Oi are stuck. Consequently, the
flow volume for drawing the oils decreases.
[0045] With reference to FIG. 4B, the inventors of the present
disclosure designed to form, in the outer circumferential surface
of the housing 30, the oil receiving portion 32b that can receive
the injected oils Oi from the nozzle 16, and to form, continuously
from the lower part of the oil receiving portion 32b, the oil
introducing hole 32c that introduces the injected oils Oi to the
oil receiving portion 32b into the interior of the housing 30. The
oils Oi are injected to the oil receiving portion 32b from the
nozzle 16, flow through the oil receiving portion 32b, and reach
the oil introducing hole 32c. The oils that have reached the oil
introducing hole 32c pass through the oil introducing hole 32c, and
reach the interior of the housing 30. Accordingly, the oils Oi
gradually flow into the interior of the housing 30. Such a
scavenging pump 20 was able to increase the flow volume of the
circulated oils in comparison with the scavenging pump 120
(.sub.see FIG. 4A) according to a comparative example. That is, the
scavenging pump 20 can further efficiently circulate the oils
Oi.
[0046] Moreover, the guide portion 32d that guides the oils Oi to
the oil introducing hole 32c is formed along the edge of the oil
introducing hole 32c at the outer-circumferential-surface side. The
guide portion 32d can guide the oils Oi to the oil introducing hole
32c. Hence, the more oils Oi injected to the oil receiving portion
32b can be guided to the interior of the housing 30, thereby
ensuring the sealing performance between the gears 22 and 23. This
causes the oils Oi to be further efficiently circulated.
[0047] With reference to FIG. 3, furthermore, the area of the oil
receiving portion 32b is larger than the area of the oil
introducing hole 32c. The injected oils can be further surely
received by the oil receiving portion 32b, and the direct injection
of the oils to the oil introducing hole 32c is suppressed. This
results in a further efficient circulation of the oils Oi.
[0048] With reference to FIG. 4B, the housing 30 has the oil
retaining portion 32e which can retain the oils together with the
guide portion 32 at the lower part of the oil introducing hole 32c.
Since the oil retaining portion 32e is formed, the oils that flows
downwardly through the oil receiving portion 32b can be further
surely introduced into the oil introducing hole 32c. Note that the
guide portion 32d may be formed in a planar shape, or may be
inclined downwardly toward the oil introducing hole 32c.
[0049] Moreover, the oil introducing hole 32c increases the
diameter toward the inner circumferential surface side from the
outer circumferential surface. When, for example, a vehicle stops
at a sloping road, the scavenging pump 10 may be inclined relative
to the horizontal axis. According to the above-described structure,
even if the scavenging pump 10 is inclined, the oils that contact
the oil receiving portion 32b can be surely introduced into the
interior of the pump.
[0050] With reference to FIG. 3, the oil receiving portion 32b is
formed so as to gradually decreases the width toward the oil
introducing hole 32c. This enables the oil receiving portion 32b to
receive the further more oils, and further surely causes the
received oils to be guided to the oil introducing hole 32c. Hence,
the oils Oi can be further efficiently circulated.
[0051] Note that, in general, the oil pan 11 (see FIG. 1) is always
filled with the oils that are equal to or greater than a certain
amount. Hence, according to the feed pump 12 that draws the oils
from the oil pan 11, a certain level of sealing performance between
the gears is maintained. That is, under a predetermined condition,
the problem such that the sealing performance is low between the
gears 22 and 23 like the scavenging pump 20 is not likely to occur
at all. In this point, the feed pump 12 and the scavenging pump 20
remarkably differ from each other.
[0052] Although the scavenging pump according to the present
disclosure has been described with reference to an example case
applied to a vehicle, it can be applied to conveyances other than
vehicles, and construction machineries, etc., and the present
disclosure is not limited to such forms. Moreover, although the
scavenging pump that is an internal-gear pump has been described as
an example, internal-contact gear pump to an example, the present
disclosure is applicable to an external-contact gear pump.
[0053] That is, as far as the actions and advantageous effects of
the present disclosure are accomplishable, the present disclosure
is not limited to the embodiments.
INDUSTRIAL APPLICABILITY
[0054] The scavenging pump according to the present disclosure is
suitable to draw oils for cooling a vehicle to an oil pan.
* * * * *