U.S. patent application number 14/140317 was filed with the patent office on 2015-03-12 for engine having variable valve timing device.
This patent application is currently assigned to Hyundai Motor Company. The applicant listed for this patent is Hyundai Motor Company. Invention is credited to Yoonhan EO, Dongsun KIM.
Application Number | 20150068474 14/140317 |
Document ID | / |
Family ID | 52624273 |
Filed Date | 2015-03-12 |
United States Patent
Application |
20150068474 |
Kind Code |
A1 |
KIM; Dongsun ; et
al. |
March 12, 2015 |
ENGINE HAVING VARIABLE VALVE TIMING DEVICE
Abstract
An engine having a variable valve timing device of the present
invention may include a valve disposed to open/close a port, an
elastic member for supporting the valve elastically to close the
port, a first camshaft having a first cam formed thereon for moving
the valve to open the port as the first camshaft rotates, a second
camshaft having a second cam formed thereon for moving the valve to
close the port as the second camshaft rotates, a first variable
rotation mechanism for advancing or retarding the rotation of the
first camshaft, and a second variable rotation mechanism for
advancing or retarding the rotation of the second camshaft.
Inventors: |
KIM; Dongsun; (Seoul,
KR) ; EO; Yoonhan; (Hwaseong-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company |
Seoul |
|
KR |
|
|
Assignee: |
Hyundai Motor Company
Seoul
KR
|
Family ID: |
52624273 |
Appl. No.: |
14/140317 |
Filed: |
December 24, 2013 |
Current U.S.
Class: |
123/90.15 |
Current CPC
Class: |
F01L 1/34416 20130101;
F01L 2001/0473 20130101; F01L 1/3442 20130101; F01L 1/047 20130101;
F01L 1/0532 20130101; F01L 2001/34489 20130101 |
Class at
Publication: |
123/90.15 |
International
Class: |
F01L 1/34 20060101
F01L001/34 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 6, 2013 |
KR |
10-2013-0107425 |
Claims
1. An engine having a variable valve timing device comprising: a
valve disposed to open or close a port; an elastic member
configured for supporting the valve elastically to close the port;
a first camshaft having a first cam formed thereon for moving the
valve to open the port as the first camshaft rotates; a second
camshaft having a second cam formed thereon for moving the valve to
close the port as the second camshaft rotates; a first variable
rotation mechanism for advancing or retarding the rotation of the
first camshaft; and a second variable rotation mechanism for
advancing or retarding the rotation of the second camshaft.
2. The engine having the variable valve timing device of claim 1,
wherein the first variable rotation mechanism or the second
variable rotation mechanism is formed at a pulley or a sprocket for
having a torque forwarded thereto to rotate the first camshaft and
the second camshaft.
3. The engine having the variable valve timing device of claim 1,
wherein the second camshaft is slidably inserted into the first
camshaft, and the second cam penetrates the first camshaft to
operate the valve.
4. The engine having the variable valve timing device of claim 1,
wherein the first variable rotation mechanism or the second
variable rotation mechanism includes an advance angle chamber and a
retard angle chamber for advancing rotation of the first camshaft
and the second camshaft or retarding rotation of the first camshaft
and the second camshaft.
5. The engine having the variable valve timing device of claim 4,
further comprising: first and second oil control valves matched to
the first variable rotation mechanism and the second variable
rotation mechanism for selective forwarding of hydraulic oil to the
advance angle chamber or the retard angle chamber; and a hydraulic
pump for pumping the hydraulic oil to the first and second oil
control valves.
6. The engine having the variable valve timing device of claim 4,
further comprising: a control unit for sensing rotation positions
of the first cam and the second cam, and an RPM of a crankshaft,
and determining an engine load, and sensing a position of an
accelerator pedal, and controlling the first and second oil control
valves according to operation information sensed thus.
7. The engine having the variable valve timing device of claim 1,
wherein the first variable rotation mechanism is disposed to one
end of the first camshaft, and the second variable rotation
mechanism is disposed to the other end of the second camshaft.
8. The engine having the variable valve timing device of claim 3,
wherein the first variable rotation mechanism has a torque
forwarded thereto from the crankshaft to rotate the first camshaft,
and the second variable rotation mechanism rotates the second
camshaft by rotation of the first camshaft to advance or retard the
second camshaft with reference to the first camshaft.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to Korean Patent
Application No. 10-2013-0107425 filed on Sep. 6, 2013, the entire
contents of which is incorporated herein for all purposes by this
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an engine having a variable
valve timing device which controls opening time, duration of
opening, and closing time of an intake or an exhaust valve which
opens or closes an intake or exhaust port for improving total
energy consumption efficiency.
[0004] 2. Description of Related Art
[0005] An internal combustion engine generates power by receiving
and burning fuel and air in a combustion chamber. At the time of
intake of the air, a camshaft is driven to operate the intake valve
to draw air into the combustion chamber during the intake valve is
opened.
[0006] In addition, the camshaft is driven to operate the exhaust
valve to discharge the air from the combustion chamber during the
exhaust valve is opened.
[0007] In the meantime, optimum opening/closing times and duration
of the opening of the intake valve/exhaust valve vary with
operation conditions, such as a rotation speed of the engine or an
engine load.
[0008] That is, proper timing (lift) or valve opening/closing vary
with the rotation speed of the engine.
[0009] In the meantime, when one valve is opened/closed with a cam,
if the opening time is retarded, the closing time is retarded too,
and if the opening time is advanced, the closing time is advanced
too. Study for extension/shortening of the duration of opening
between the opening time and the closing time is also underway.
[0010] A prior art discloses a camshaft having a first cam and a
second cam for driving one valve, wherein the camshaft has a
structure in which individual advance or retard of the first cam
and the second cam is not possible.
[0011] The information disclosed in this Background of the
Invention 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
[0012] Various aspects of the present invention are directed to
providing an engine having a variable valve timing device having an
advantage of improving total efficiency. An object of the present
invention is to provide an engine having a variable valve timing
device which can retard or advance an opening time and a closing
time of a valve, as well as extend or shorten duration of opening
between the opening time and the closing time for improving total
efficiency.
[0013] In an aspect of the present invention, an engine having a
variable valve timing device may include a valve disposed to open
or close a port, an elastic member configured for supporting the
valve elastically to close the port, a first camshaft having a
first cam formed thereon for moving the valve to open the port as
the first camshaft rotates, a second camshaft having a second cam
formed thereon for moving the valve to close the port as the second
camshaft rotates, a first variable rotation mechanism for advancing
or retarding the rotation of the first camshaft, and a second
variable rotation mechanism for advancing or retarding the rotation
of the second camshaft.
[0014] The first variable rotation mechanism or the second variable
rotation mechanism is formed at a pulley or a sprocket for having a
torque forwarded thereto to rotate the first camshaft and the
second camshaft.
[0015] The second camshaft is slidably inserted into the first
camshaft, and the second cam penetrates the first camshaft to
operate the valve.
[0016] The first variable rotation mechanism or the second variable
rotation mechanism may include an advance angle chamber and a
retard angle chamber for advancing rotation of the first camshaft
and the second camshaft or retarding rotation of the first camshaft
and the second camshaft.
[0017] The engine having the variable valve timing device may
further may include first and second oil control valves matched to
the first variable rotation mechanism and the second variable
rotation mechanism for selective forwarding of hydraulic oil to the
advance angle chamber or the retard angle chamber, and a hydraulic
pump for pumping the hydraulic oil to the first and second oil
control valves.
[0018] The engine having the variable valve timing device may
further may include a control unit for sensing rotation positions
of the first cam and the second cam, and an RPM of a crankshaft,
and determining an engine load, and sensing a position of an
accelerator pedal, and controlling the first and second oil control
valves according to operation information sensed thus.
[0019] The first variable rotation mechanism is disposed to one end
of the first camshaft, and the second variable rotation mechanism
is disposed to the other end of the second camshaft.
[0020] The first variable rotation mechanism may have a torque
forwarded thereto from the crankshaft to rotate the first camshaft,
and the second variable rotation mechanism rotates the second
camshaft by rotation of the first camshaft to advance or retard the
second camshaft with reference to the first camshaft.
[0021] To achieve the object of the present invention, the opening
time of the valve may be retarded or advanced with the first
camshaft and the first cam, and the closing time of the valve may
be retarded or advanced with the second camshaft and the second
cam.
[0022] Along with this, the duration of opening of the valve may be
controlled easily by controlling the opening time and the closing
time of the valve, individually.
[0023] 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
[0024] FIG. 1 illustrates a schematic perspective view of a part of
an engine having a variable valve timing device in accordance with
an exemplary embodiment of the present invention.
[0025] FIGS. 2A.about.2C illustrate side views of a part of an
engine having a variable valve timing device in accordance with an
exemplary embodiment of the present invention.
[0026] FIG. 3 illustrates a schematic diagram of an engine having a
variable valve timing device in accordance with an exemplary
embodiment of the present invention.
[0027] FIG. 4 illustrates a schematic diagram of an engine having a
variable valve timing device in accordance with an exemplary
embodiment of the present invention.
[0028] 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.
[0029] 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
[0030] 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 the 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.
[0031] An exemplary embodiment of the present invention will
hereinafter be described in detail with reference to the
accompanying drawings.
[0032] FIG. 1 illustrates a schematic perspective view of a part of
an engine having a variable valve lift timing device in accordance
with an exemplary embodiment of the present invention.
[0033] Referring to FIG. 1, the engine includes a first camshaft
100, a second camshaft 110, a first cam 105 and a second cam 115.
The first camshaft 100 and the second camshaft 110 have a structure
in which the first camshaft 100 and the second camshaft 110 are
disposed and rotate on the same axis.
[0034] The first camshaft 100 has one end with the first cam 105
formed thereon, and the second camshaft 110 has the other end with
the second cam 115 formed thereon, wherein the first cam 105 and
the second cam 115 may be disposed adjacent to each other.
[0035] In an exemplary embodiment of the present invention, the
first cam 105 and the second cam 115 open or close one valve 120,
and the first camshaft 100 is rotated in retard or advance by a
crankshaft to rotate the first cam 105 in retard or advance.
[0036] Along with this, the second camshaft 110 may be rotated in
retard or advance by the crankshaft to rotate the second cam 115 in
retard or advance.
[0037] FIGS. 2A.about.2C illustrate side views of a part of an
engine having a variable valve timing device in accordance with an
exemplary embodiment of the present invention.
[0038] Referring to FIG. 2, the first cam 105 and the second cam
115 are disposed on a top side, and the valve 120 is disposed under
the first cam 105 and the second cam 115. Further, an elastic
member 200 supports the valve 120 upward elastically to bring the
valve 120 into close contact with the first and second cams 105 and
115.
[0039] Referring to FIG. 2A, since both of the first cam 105 and
the second cam 115 are retarded, both of the opening time and the
closing time of the valve 120 are retarded, and the duration of
opening of the valve 120 becomes short.
[0040] Referring to FIG. 2B, since the first cam 105 is retarded
and the second cam 115 is advanced, the opening time of the valve
120 is advanced, the closing time of the valve 120 is retarded, and
the duration of the opening is extended.
[0041] Referring to FIG. 2C, since both of the first cam 105 and
the second cam 115 are advanced, both of the opening time and the
closing time are advanced, and the duration of opening of the valve
120 is shortened.
[0042] FIG. 3 illustrates a schematic diagram of an engine having a
variable valve timing device in accordance with an exemplary
embodiment of the present invention.
[0043] Referring to FIG. 3, the engine having a variable valve
timing device includes a control unit 300, a hydraulic pump 310, a
first oil control valve 320, a second oil control valve 330, a
first variable rotation mechanism 340, a second variable rotation
mechanism 350, a first camshaft 100, a second camshaft 110, a first
cam 105 and a second cam 115
[0044] The first camshaft 100 has a left side end with the first
variable rotation mechanism 340 disposed thereto, and the second
camshaft 110 inserted therein. In addition, the second camshaft 110
has a right side end with the second variable rotation mechanism
350 disposed thereto.
[0045] The first cam 105 is formed protruded from one side of an
outside circumference of the first camshaft 100, and the second cam
115 is formed protruded from one side of an outside circumference
of the first camshaft 100 passed through the first camshaft
100.
[0046] In an exemplary embodiment of the present invention, the
first cam 105 and the second cam 115 may be formed to the same
heights from the outside circumference of the first camshaft 100,
respectively.
[0047] The first variable rotation mechanism 340 makes the first
cam 105 to retard or advance through the first camshaft 100, and
the second variable mechanism 350 makes the second cam 115 to
retard or advance through the second camshaft 110.
[0048] The first variable rotation mechanism 340 has a retard angle
chamber 342 or 352 and an advance angle chamber 344 or 345 formed
therein, and the first oil control valve 320 supplies oil to the
retard angle chamber 342 or 352 and the advance angle chamber 344
or 345 for retarding or advancing the first camshaft 100.
[0049] Along with this, the second variable rotation mechanism 350
has a retard angle chamber 342 or 352 and an advance angle chamber
344 or 345 formed therein, and the second oil control valve 330
supplies oil to the retard angle chamber 342 or 352 and the advance
angle chamber 344 or 345 for retarding or advancing the second
camshaft 110.
[0050] The hydraulic pump 310 pumps the oil to the first oil
control valve 320 and the second oil control valve 330 at a preset
pressure.
[0051] Further, the control unit 300 controls the first oil control
valve 320 and the second oil control valve 330 to retard or advance
the first cam 105 and the second cam 115 individually according to
operation information including a position of an opening cam (The
first cam), a position of a closing cam (The second cam), the
engine rotation speed (RPM), an engine load and a position of an
accelerator pedal.
[0052] FIG. 4 illustrates a schematic diagram of an engine having a
variable valve timing device in accordance with an exemplary
embodiment of the present invention.
[0053] Referring to FIG. 4, the crankshaft 420 in the engine
generates a torque, and the first variable rotation mechanism 340
has the torque forwarded thereto from the crankshaft 420 through a
chain or a belt 400, to rotate the first camshaft 100. Along with
this, the first variable rotation mechanism 340 makes the rotation
of the first camshaft 100 retarded or advanced.
[0054] The second variable mechanism 350 is rotated by the first
camshaft 100, and the second variable rotation mechanism 350 may
make the second camshaft 110 to be retarded or advanced with
reference to the first camshaft 100.
[0055] Though FIG. 4 illustrates the first variable rotation
mechanism 340 having a torque forwarded thereto from the crankshaft
420, and the second variable rotation mechanism 350 having a torque
forwarded thereto from the first camshaft 100, the second variable
rotation mechanism 350 may have the torque forwarded thereto from
the crankshaft 420, and the first variable rotation mechanism 340
may have the torque forwarded thereto from the second camshaft
420.
[0056] Along with this, the first variable rotation mechanism 340
and the second variable rotation mechanism 350 may have the torque
forwarded thereto from the crankshaft 420, individually.
[0057] For convenience in explanation and accurate definition in
the appended claims, the terms "upper", "lower", "inner" and
"outer" are used to describe features of the exemplary embodiments
with reference to the positions of such features as displayed in
the figures.
[0058] 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. 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 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.
* * * * *