U.S. patent application number 13/889626 was filed with the patent office on 2014-06-19 for lubrication apparatus of high pressure pump for common rail system.
This patent application is currently assigned to Hyundai Motor Company. The applicant listed for this patent is HYUNDAI MOTOR COMPANY. Invention is credited to Chang Sun Hwang, Sun Dong Kwun, Sung il You.
Application Number | 20140165957 13/889626 |
Document ID | / |
Family ID | 50821536 |
Filed Date | 2014-06-19 |
United States Patent
Application |
20140165957 |
Kind Code |
A1 |
Kwun; Sun Dong ; et
al. |
June 19, 2014 |
LUBRICATION APPARATUS OF HIGH PRESSURE PUMP FOR COMMON RAIL
SYSTEM
Abstract
A lubrication apparatus of a high pressure pump for a common
rail system can improve lubrication performance for a friction
portion M1 between a roller 12 and a shoe by supplying a large
amount of lubricating fuel, which is supplied from a low pressure
pump 24, to the friction portion M1 for a short time.
Inventors: |
Kwun; Sun Dong; (Suwon-si,
KR) ; You; Sung il; (Gwacheon-si, KR) ; Hwang;
Chang Sun; (Incheon, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HYUNDAI MOTOR COMPANY |
Seoul |
|
KR |
|
|
Assignee: |
Hyundai Motor Company
Seoul
KR
|
Family ID: |
50821536 |
Appl. No.: |
13/889626 |
Filed: |
May 8, 2013 |
Current U.S.
Class: |
123/196R |
Current CPC
Class: |
F02M 59/44 20130101;
F02M 59/102 20130101; F02M 63/0001 20130101; F04B 53/18
20130101 |
Class at
Publication: |
123/196.R |
International
Class: |
F01M 11/02 20060101
F01M011/02 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 17, 2012 |
KR |
10-2012-0147886 |
Claims
1. A lubrication apparatus of a high pressure pump for a common
rail system, the apparatus comprising: a first lubrication passage
connecting a shaft chamber formed in a pump housing with a low
pressure pump and a high pressure pump; and a support lubrication
passage with one end connected to the first lubrication passage and
the other end connected to a friction portion where a roller and a
shoe are in contact with each other.
2. The apparatus of claim 1, further comprising a check valve
disposed in the support lubrication passage, allows the flow of
fuel from the first lubrication passage to the support lubrication
passage, and prevents backflow of fuel from the support lubrication
passage to the first lubrication passage.
3. The apparatus of claim 2, wherein the support lubrication
passage includes: a diverging passage that diverges from the first
lubrication passage and then extends into the roller; and open
passages connected with the diverging passage and open to the
friction portion.
4. The apparatus of claim 2, wherein the check valve is disposed in
the diverging passage.
5. The apparatus of claim 3, wherein the diverging passage is
positioned at the rotational center of the roller.
6. The apparatus of claim 3, wherein a plurality of open passages
is provided to simultaneously supply fuel to the friction portion.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority of Korean Patent
Application Number 10-2012-0147886 filed Dec. 17, 2012, the entire
contents of which application is incorporated herein for all
purposes by this reference.
BACKGROUND OF INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to a lubrication apparatus of
a high pressure pump for a common rail system, and more
particularly, a lubrication apparatus of a high pressure pump for a
common rail system which can improve lubricating performance of a
friction portion where a roller and a shoe are in contact.
[0004] 2. Description of Related Art
[0005] A high pressure pump 10 used in common rail systems, as
shown in FIGS. 1 and 2, includes a pump housing 11, a roller 12, a
shoe 13, and a plunger 14 wherein a shaft chamber 11a, a roller
chamber 11b, and spring chamber 11c are connected in the pump
housing 11.
[0006] A camshaft 21 with a cam 21a is rotatably disposed in the
shaft chamber 11a, the roller 12 and the shoe 13 are disposed in
contact with the cam 21a in the roller chamber 11b, and a spring 16
is disposed on a spring seat 15 in the spring chamber 11c.
[0007] The plunger 14 is disposed with one end in contact with the
shoe 13 and the other end in a fuel compression chamber 17
positioned between an inlet valve 22 and an outlet valve 23.
[0008] The inlet valve 22 is a valve disposed in a fuel passage
connected with a low pressure pump 24 and the outlet valve 23 is a
valve disposed in a fuel passage connected with a common rail
25.
[0009] Therefore, as the cam shaft 21 is rotated by driving an
engine, the roller 12 pushes the shoe 13 while rotating in
accordance with the lift of the profile of the cam and the plunger
14 is reciprocated by the shoe 13 pushed. Further, low pressure
fuel supplied to the fuel compression chamber 17 through the inlet
valve 22 by the motion of the plunger 14 is compressed at high
pressure and then flows out to the common rail 25 through the
outlet valve 23.
[0010] Meanwhile, the roller 12 and the shoe 13 are in contact
under high pressure, so that the wear is caused by friction and
burning and sticking are caused, if excessive, unless a friction
portion M1 where the roller 12 and the shoe 13 are in contact is
sufficiently lubricated; therefore, the friction portion M1 between
the roller 12 and the shoe 13 is usually lubricated with fuel from
a low pressure pump 24 to preclude those problems.
[0011] That is, in the related art, the friction portion M1 between
the roller 12 and the shoe 13 is lubricated by using a first
lubrication passage 31 connecting the low pressure pump 24 with the
shaft chamber 11a of the pump housing 11 and a second lubrication
passage 32 connecting the shaft chamber 11a with the spring chamber
11c, so that the shaft chamber 11a is filled with the fuel from the
low pressure chamber 24 and then the spring chamber 11c is filled,
and thereafter, the fuel is applied to the friction portion M1
between the roller 12 and the shoe 13, thereby lubricating the
friction portion M1.
[0012] However, there is a defect in the structure of the related
art described above in that the lubricating fuel flows a long
distance to the friction portion M1 between the roller 12 and the
shoe 13, so that the camshaft 21 operates before the friction
portion M1 between the roller 12 and the shoe 13 is sufficiently
lubricated, and in this case, not only the friction portion M1
between the roller 12 and the shoe 13 under large compressive load
is severely worn, but the high pressure pump 10 is broken due to
burning and sticking, if excessive.
[0013] An exemplar of the prior art is Korean Patent Publication
No. 10-2005-0051372
[0014] The information disclosed in this Background section is only
for enhancement of understanding of the general background of the
invention and should not be taken as an acknowledgement or any form
of suggestion that this information forms the prior art already
known to a person skilled in the art.
BRIEF SUMMARY
[0015] The present invention has been made in an effort to solve
the defects described above.
[0016] Various aspects of the present invention provide for provide
a lubrication apparatus of a high pressure pump for a common rail
system which allows sufficient lubrication of a friction portion by
reducing the path along which lubricating fuel flows to the
friction portion where a roller and a shoe are in contact, prevents
wear between the roller and the shoe due to friction by improving
lubricating performance on the friction portion between the roller
and the shoe, and also improves the performance of a high pressure
pump.
[0017] Various aspects of the present invention provide for a
lubrication apparatus of a high pressure pump for a common rail
system including: a first lubrication passage connecting a shaft
chamber formed in a pump housing with a low pressure pump in a high
pressure pump; and a support lubrication passage with one end
connected to the first lubrication passage and the other end
connected to a friction portion where a roller and a shoe are in
contact.
[0018] The apparatus may further include a check valve that is
disposed in the support lubrication passage, allows the flow of
fuel from the first lubrication passage to the support lubrication
passage, and prevents backflow of fuel from the support lubrication
passage to the first lubrication passage.
[0019] The support lubrication passage may include: a diverging
passage that diverges from the first lubrication passage and then
extends into the roller; and open passages that are connected with
the diverging passage and open to the friction portion.
[0020] The check valve may be disposed in the diverging
passage.
[0021] The diverging passage may be positioned at the rotational
center of the roller.
[0022] A plurality of open passages may be provided to
simultaneously supply a large amount of fuel to the friction
portion.
[0023] It is understood that the term "vehicle" or "vehicular" or
other similar term as used herein is inclusive of motor vehicles in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g. fuels derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example both
gasoline-powered and electric-powered vehicles.
[0024] The methods and apparatuses of the present invention have
other features and advantages which will be apparent from or are
set forth in more detail in the accompanying drawings, which are
incorporated herein, and the following Detailed Description, which
together serve to explain certain principles of the present
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIGS. 1 and 2 are views illustrating a lubrication apparatus
of a high pressure pump for a common rail system of the related
art.
[0026] FIGS. 3, 4 and 5 are views illustrating an exemplary
lubrication apparatus of a high pressure pump for a common rail
system according to the present invention.
[0027] It should be understood that the appended drawings are not
necessarily to scale, presenting a somewhat simplified
representation of various features illustrative of the basic
principles of the invention. The specific design features of the
present invention as disclosed herein, including, for example,
specific dimensions, orientations, locations, and shapes will be
determined in part by the particular intended application and use
environment.
[0028] In the figures, reference numbers refer to the same or
equivalent parts of the present invention throughout the several
figures of the drawing.
DETAILED DESCRIPTION
[0029] Reference will now be made in detail to various embodiments
of the present invention(s), examples of which are illustrated in
the accompanying drawings and described below. While the
invention(s) will be described in conjunction with exemplary
embodiments, it will be understood that present description is not
intended to limit the invention(s) to those exemplary embodiments.
On the contrary, the invention(s) is/are intended to cover not only
the exemplary embodiments, but also various alternatives,
modifications, equivalents and other embodiments, which may be
included within the spirit and scope of the invention as defined by
the appended claims.
[0030] A high pressure pump 10 for a common rail system according
to various embodiments of the present invention, as shown in FIGS.
3 to 5, includes a pump housing 11, a roller 12, a shoe 13, and a
plunger 14, in which a shaft chamber 11a, a roller chamber 11b, and
spring chamber 11c are connected in the pump housing 11.
[0031] A camshaft 21 with a cam 21a is rotatably disposed in the
shaft chamber 11a, the roller 12 and the shoe 13 are disposed in
contact with the cam 21a in the roller chamber 11b, and a spring 16
is disposed on a spring seat 15 in the spring chamber 11c.
[0032] The plunger 14 is disposed with one end in contact with the
shoe 13 and the other end in a fuel compression chamber 17
positioned between an inlet valve 22 and an outlet valve 23.
[0033] The inlet valve 22 is a valve disposed in a fuel passage
connected with a low pressure pump 24 and the outlet valve 23 is a
valve disposed in a fuel passage connected with a common rail
25.
[0034] Therefore, as the cam shaft 21 is rotated by driving an
engine, the roller 12 pushes the shoe 13 while rotating in
accordance with the lift of the profile of the cam and the plunger
14 is reciprocated by the shoe 13 pushed. Further, low pressure
fuel supplied to the fuel compression chamber 17 through the inlet
valve 22 by the motion of the plunger 14 is compressed at high
pressure and then flows out to the common rail 25 through the
outlet valve 23.
[0035] Meanwhile, the roller 12 and the shoe 13 are in contact
under high pressure, so that the wear is caused by friction and
burning and sticking are caused, if excessive, unless a friction
portion M1 where the roller 12 and the shoe 13 are in contact is
sufficiently lubricated; therefore, the friction portion M1 between
the roller 12 and the shoe 13 is lubricated with fuel from a low
pressure pump 24 to preclude those problems.
[0036] That is, the lubricating apparatus of a high pressure pump
according to various embodiments of the present invention includes,
in a high pressure pump 10, a first lubrication passage 31
connecting the shaft chamber 11a in the pump housing 11 with a low
pressure pump 24, a second lubrication passage 32 connecting the
shaft chamber 11a with the spring chamber 11c, and a support
lubrication passage 33 with one end connected to the first
lubrication passage 31 and the other end connected to the friction
portion M1 where the roller 12 and the shoe 13 are in contact.
[0037] Further, the lubricating apparatus according to various
embodiments of the present invention further includes a check valve
34 that is disposed in the support lubrication passage 33, allows
the flow of fuel from the first lubrication passage 31 to the
support lubrication passage 33, and prevents backflow of fuel from
the support lubrication passage 33 to the first lubrication passage
31.
[0038] The support lubrication passage 33 is composed of a
diverging passage 33a that diverges from the first lubrication
passage 31 and then extends into the roller 12 and open passages
33b that are connected with the diverging passage 33a and open to
the friction portion M1.
[0039] One check valve 34 is disposed at the inlet of the diverging
passage 33a, but if the check valve 34 is disposed at each other
open passages 33b, the number of articles, the cost, and the weight
increase.
[0040] Further, the diverging passage 33a may be positioned at the
rotational center of the roller 12 for smooth flow of lubricating
fuel.
[0041] If the diverging passage 33a is biased to a side from the
rotational center of the roller 12, the fuel passing through the
diverging passage 33a is biased to a side by a centrifugal force in
rotation of the roller 12, so that resistance is generated in the
flow of the fuel flowing to the open passages 33b from the
diverging passage 33a, and accordingly, the fuel cannot smoothly
flow to the open passages 33b from the diverging passage 33a.
[0042] Further, a plurality of open passages 33b may be formed in
order to simultaneously supply a large amount of fuel to the
friction portion M1 in consideration of the durability of the
roller 12.
[0043] According to various embodiments of the present invention
described above, some of the lubricating fuel flowing to the shaft
chamber 11a of the pump housing 11 through the first lubrication
passage 31 from the low pressure pump 24 is directly supplied to
the friction portion M1 between the roller 12 and the shoe 13
through the support lubrication passage 33.
[0044] Therefore, compared with the related art, it is possible to
considerably reduce the path of the lubricating fuel supplied to
the friction portion M1 between the roller 12 and the shoe 13, to
reduce the time taken to lubricate the friction portion M1, and to
operate the camshaft 21 after the friction portion M1 is
sufficiently lubricated, so that it is possible to prevent wear of
the friction portion M1 as much as possible, and accordingly, it is
possible to significantly improve the durability of the high
pressure pump 10.
[0045] Further, the lubricating fuel supplied to the shaft chamber
11a through the first lubrication passage 31 flows to the spring
chamber 11c through the second lubrication passage 32 after filling
the shaft chamber 11a and the lubricating fuel supplied to the
spring chamber 11c is additionally supplied to the friction portion
M1 between the roller 12 and the shoe 13 by rotation of the cam 21a
and the roller, so that lubrication performance for the friction
portion M1 between the roller 12 and the shoe 13 is considerably
improved.
[0046] According to the present invention, as a large amount of
lubricating fuel supplied from a low pressure pump is supplied to a
friction portion between a roller and a shoe, it is possible to
prevent wear of the friction portion as much as possible and to
considerably improve the durability of a high pressure pump.
[0047] The foregoing descriptions of specific exemplary embodiments
of the present invention have been presented for purposes of
illustration and description. They are not intended to be
exhaustive or to limit the invention to the precise forms
disclosed, and obviously many modifications and variations are
possible in light of the above teachings. The exemplary embodiments
were chosen and described in order to explain certain principles of
the invention and their practical application, to thereby enable
others skilled in the art to make and utilize various exemplary
embodiments of the present invention, as well as various
alternatives and modifications thereof. It is intended that the
scope of the invention be defined by the Claims appended hereto and
their equivalents.
* * * * *