U.S. patent application number 14/570274 was filed with the patent office on 2015-12-10 for manual transmission oil composition having enhanced fuel efficiency and low viscosity.
The applicant listed for this patent is Hyundai Motor Company, Kia Motors Corporation. Invention is credited to Dae Yun Bae, Sung Uk Lee.
Application Number | 20150353861 14/570274 |
Document ID | / |
Family ID | 54706776 |
Filed Date | 2015-12-10 |
United States Patent
Application |
20150353861 |
Kind Code |
A1 |
Lee; Sung Uk ; et
al. |
December 10, 2015 |
MANUAL TRANSMISSION OIL COMPOSITION HAVING ENHANCED FUEL EFFICIENCY
AND LOW VISCOSITY
Abstract
Disclosed is a manual transmission oil composition which
include: (A) a polyalphaolefin (PAO) synthetic base oil in an
amount of about 75 to 85 wt %; (B) an ester-based viscosity
modifier in an amount of about 3 to 10 wt %; and (C) an additive in
an amount of about 8 to 15 wt % which includes one or more of an
anti-wear agent, a detergent dispersant, a friction modifier, an
extreme pressure additive, and an anti-oxidant, based on the total
weight of the manual transmission oil composition. Accordingly, the
manual transmission oil composition may have a low viscosity as
compared to conventional manual transmission oils, and may provide
improvements in endurance of a transmission, reduction in a Rattle
noise, and further improvement in fuel efficiency of vehicles by
about 1 to 2%.
Inventors: |
Lee; Sung Uk; (Boryeong,
KR) ; Bae; Dae Yun; (Yongin, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company
Kia Motors Corporation |
Seoul
Seoul |
|
KR
KR |
|
|
Family ID: |
54706776 |
Appl. No.: |
14/570274 |
Filed: |
December 15, 2014 |
Current U.S.
Class: |
508/459 |
Current CPC
Class: |
C10N 2040/044 20200501;
C10N 2020/04 20130101; C10N 2030/54 20200501; C10M 2209/084
20130101; C10N 2020/02 20130101; C10M 2205/028 20130101; C10M
169/041 20130101; C10M 169/042 20130101; C10M 2205/0285 20130101;
C10N 2030/76 20200501; C10M 2205/028 20130101; C10M 2209/08
20130101 |
International
Class: |
C10M 169/04 20060101
C10M169/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 10, 2014 |
KR |
10-2014-0070362 |
Claims
1. A manual transmission oil composition comprising: a
polyalphaolefin (PAO) synthetic base oil in an amount of about 75
to 85 wt % based on the total weight of the manual transmission oil
composition; an ester-based viscosity modifier in an amount of
about 3 to 10 wt % based on the total weight of the manual
transmission oil composition; and an additive in an amount of about
8 to 15 wt % based on the total weight of the manual transmission
oil composition, wherein the additive comprises one or more
selected from an anti-wear agent, a detergent dispersant, a
friction modifier, an extreme pressure additive, and an
anti-oxidant.
2. The manual transmission oil composition of claim 1, wherein the
ester-based viscosity modifier is a hybrid olefin ester-based
copolymer having a backbone including units derived from a C.sub.6
or more .alpha.-olefin monomer and an ethylenically unsaturated
carboxylic acid or derivatives thereof.
3. The manual transmission oil composition of claim 1, wherein the
manual transmission oil composition further comprises polyalkyl
methacrylate in an amount of about 3 to 5 wt % as the viscosity
modifier.
4. The manual transmission oil composition of claim 3, wherein the
polyalkyl methacrylate has a number average molecular weight of
about 300,000 to 400,000 and about four to six C.sub.12 to C.sub.15
polymer chains.
5. A manual transmission oil of claim 1, wherein the manual
transmission oil has an average kinematic viscosity of about 5 to 6
cSt at a temperature of about 100.degree. C., an average kinematic
viscosity of about 24 to 30 cSt at a temperature of about
40.degree. C., and an average absolute viscosity of about 4,000 to
10,000 cP at a temperature of about -40.degree. C.
6. A manual transmission oil of claim 1 which consists essentially
of the polyalphaolefin (PAO) synthetic base oil; ester-based
viscosity modifier; and additive.
7. A manual transmission oil of claim 1 which consists of the
polyalphaolefin (PAO) synthetic base oil; ester-based viscosity
modifier; and additive.
8. A vehicle that comprises a manual transmission oil of claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims under 35 U.S.C. .sctn.119(a) the
benefit of Korean Patent Application No. 10-2014-0070362 filed on
Jun. 10, 2014, the entire contents of which are incorporated herein
by reference.
TECHNICAL FIELD
[0002] The present disclosure relates to a manual transmission oil
composition having improved fuel efficiency and a reduced
viscosity. The manual transmission oil composition includes an
ester-based viscosity modifier as a viscosity modifier which is
added in a predetermined amount to a polyalphaolefin (PAO)
synthetic base oil thereby reducing a viscosity difference in
various ranges of temperatures. Accordingly, the endurance of a
transmission may be improved even though a viscosity of the
composition is reduced, and fuel efficiency and low temperature
gear-shifting performance of vehicles may be improved.
BACKGROUND
[0003] Generally, a transmission is a device installed between a
clutch and a thrust shaft or between the clutch and a final
reduction gear to change turning force and a speed. Accordingly,
power of an engine may be adjusted for a driving state of vehicles
and thus the turning force and the speed may be transferred to a
driving wheel. For example, a manual transmission changes a turning
speed and turning force transferred from the engine through gear
shifting according to a clutch operation and a driving condition
which may be required to curb power, and transfers the turning
speed and turning force to the driving wheel, and thus, a speed and
torque required by a driver may be obtained.
[0004] In the related arts, the manual transmission for a vehicle
has a synchronizer gear-shifting apparatus so as to smoothly
perform a gear-shifting operation of the driver. The synchronizer
gear-shifting apparatus may be an apparatus adjusting speeds of a
clutch gear and a single gear during gear-shifting thereby
providing a smooth gear-shifting operation. The synchronizer
gear-shifting apparatus may be combined with a sleeve forming
gearing while speed synchronization of the clutch gear and the
single gear may be performed due to a contact of a synchromesh and
an inclined surface of the single gear. When the oil viscosity is
substantially increased, synchronization due to friction during the
contact may be disturbed and the ability to sense gear-shifting may
be reduced, particularly at an ambient air temperature of about -20
to -50.degree. C. or less, thereby causing failure of
gear-shifting.
[0005] In related arts, a method of reducing a viscosity of an oil
at low temperatures has been developed. However, when the viscosity
at the low temperature is reduced, the viscosity at high
temperatures may be reduced accordingly, and thus this manual
transmission oil may aggravate endurance of a transmission and a
Rattle noise may be worsened.
[0006] Therefore, there is an unmet need for development of a
manual transmission oil composition which may have the reduce
viscosity and simultaneously improved endurance of the
transmission, fuel efficiency, and low temperature gear-shifting
performance.
[0007] The above information disclosed in this Background section
is only for enhancement of understanding of the background of the
invention and therefore it may contain information that does not
form the prior art that is already known in this country to a
person of ordinary skill in the art.
SUMMARY OF THE INVENTION
[0008] The present invention provides technical solutions to
above-described technical difficulties in the related art.
[0009] For example, when an ester-based viscosity modifier as a
viscosity modifier is added in a predetermined amount into a
polyalphaolefin (PAO) synthetic base oil, or when polyalkyl
methacrylate is further added, a viscosity difference in various
range of temperatures may be reduced, endurance of a transmission
may be improved although a total viscosity is reduced. Further,
fuel efficiency and low temperature gear-shifting performance of
vehicles may be improved.
[0010] As such, a manual transmission oil composition may be
obtained from the composition. The manual transmission oil
composition may have an average kinematic viscosity of about 5 to 6
cSt at a temperature of about 100.degree. C., an average kinematic
viscosity of about 24 to 30 cSt at a temperature of about
40.degree. C., and a low viscosity of an average absolute viscosity
of about 5,000 to 10,000 cP at a temperature of about -40.degree.
C., thereby improving endurance of a transmission and enhancing
fuel efficiency of vehicles by about 1 to 2%.
[0011] In one aspect, the present invention provides a manual
transmission oil composition. The manual transmission oil
composition may include: a polyalphaolefin (PAO) synthetic base oil
in an amount of about 75 to 85 wt %; an ester-based viscosity
modifier in an amount of about 3 to 10 wt %; and an additive in an
amount of about 8 to 15 wt % including one or more selected from an
anti-wear agent, a detergent dispersant, a friction modifier, an
extreme pressure additive, and an anti-oxidant, based on the total
weight of the manual transmission oil composition. Moreover, the
manual transmission oil composition may further include polyalkyl
methacrylate in an amount of about 3 to 5 wt % as the viscosity
modifier based on the total weight of the manual transmission oil
composition.
[0012] It is also understood that weight percents of the components
as disclosed herein are based on total weight of the composition,
unless otherwise indicated.
[0013] The present invention also provides the manual transmission
oil composition that consist essentially of, or consist of the
disclosed contents. For example, a composition is provided that
consists essentially of, or consists of: a polyalphaolefin (PAO)
synthetic base oil in an amount of about 75 to 85 wt %; an
ester-based viscosity modifier in an amount of about 3 to 10 wt %;
and an additive in an amount of about 8 to 15 wt % including one or
more selected from an anti-wear agent, a detergent dispersant, a
friction modifier, an extreme pressure additive, and an
anti-oxidant. Further, a composition is provided that consists
essentially of, or consists of, consists essentially of: a
polyalphaolefin (PAO) synthetic base oil in an amount of about 75
to 85 wt %; an ester-based viscosity modifier in an amount of about
3 to 10 wt %; an additive in an amount of about 8 to 15 wt %
including one or more selected from an anti-wear agent, a detergent
dispersant, a friction modifier, an extreme pressure additive, and
an anti-oxidant; and polyalkyl methacrylate in an amount of about 3
to 5 wt % as the viscosity modifier.
[0014] In particular, the manual transmission oil composition
according to the present invention may have a low viscosity as
compared to conventional manual transmission oils, and have
improved endurance of a transmission, reduced a Rattle noise, and
improved fuel efficiency of vehicles by about 1 to 2%.
[0015] Further provided are vehicles such as automobiles that
comprises a manual transmission oil composition as disclosed
herein. Other aspects and preferred embodiments of the invention
are discussed infra.
DETAILED DESCRIPTION
[0016] 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 sport 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.
[0017] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a," "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. As
used herein, the term "and/or" includes any and all combinations of
one or more of the associated listed items.
[0018] Unless specifically stated or obvious from context, as used
herein, the term "about" is understood as within a range of normal
tolerance in the art, for example within 2 standard deviations of
the mean. "About" can be understood as within 10%, 9%, 8%, 7%, 6%,
5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated
value. Unless otherwise clear from the context, all numerical
values provided herein are modified by the term "about".
[0019] Hereinafter reference will now be made in detail to various
exemplary embodiments of the present invention, examples of which
are illustrated in the accompanying drawings and described below.
While the invention will be described in conjunction with exemplary
embodiments, it will be understood that present description is not
intended to limit the invention to those exemplary embodiments. On
the contrary, the invention is 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.
[0020] Hereinafter, an exemplary embodiment of the present
invention will be described in detail.
[0021] The present invention provides a manual transmission oil
composition which may include: a polyalphaolefin (PAO) synthetic
base oil in an amount of about 75 to 85 wt %; an ester-based
viscosity modifier in an amount of about 3 to 10 wt %; and an
additive in an amount of about 8 to 15 wt % including one or more
selected from an anti-wear agent, a detergent dispersant, a
friction modifier, an extreme pressure additive and an
anti-oxidant.
[0022] The polyalphaolefin (PAO) synthetic base oil, as used
herein, may be a base oil. In particular, the polyalphaolefin (PAO)
synthetic base oil may have an average kinematic viscosity of about
3.8 to 4.2 cSt at a temperature of about 100.degree. C., a
viscosity index of about 120 or greater, and a pour point of about
-60.degree. C. or less. Moreover, the base oil may be produced
through a GTL (gas to liquid) process.
[0023] When the average kinematic viscosity of the base oil is less
than about 3.8 cSt at a temperature of about 100.degree. C., since
a vaporization amount is substantial under such elevated
temperature condition, an amount of the oil used may increase.
Furthermore, when the average kinematic viscosity is greater than
about 4.2 cSt, since an increase in viscosity is substantial at low
temperatures, a gear-shifting property may be reduced and fuel
efficiency may deteriorate at the low temperatures. Accordingly,
the base oil having the kinematic viscosity within the
aforementioned range may be used. In particular, the base oil may
be used in an amount of about 75 to 85 wt % based on the total
weight of the manual transmission oil composition.
[0024] The ester-based viscosity modifier, as used herein, may be
added to improve endurance of the transmission and form an oil
film. In particular, the ester-based viscosity modifier may be, but
not limited to, a hybrid olefin ester-based copolymer.
[0025] The hybrid olefin ester-based copolymer as used herein may
have a backbone including units derived from a C6 or greater
.alpha.-olefin monomer and an ethylenically unsaturated carboxylic
acid or derivatives thereof, and, the backbone may further include
a vinyl aromatic compound monomer. In particular, a mole ratio
between the C6 or more .alpha.-olefin monomer and the ethylenically
unsaturated carboxylic acid or derivatives thereof may be of about
1:3 to 3:1. Further, the copolymer may selectively include a
nitrogen functional group. Moreover, an ester functional group of
the copolymer may be derived from an alcohol mixture as described
in International Publication No. WO2013-123160, which is
incorporated herein by reference in its entirety. It is also
appreciated that MERIDIAN.TM. from Lubrizol Corp may provide a
suitable option for a representative viscosity modifier. In the
related arts, however, the hybrid olefin ester-based polymer has
not yet used or added to the manual transmission oil to improve
endurance of the transmission.
[0026] The ester-based viscosity modifier may be used in an amount
of about 3 to 10 wt % based on the total weight of the manual
transmission oil composition or particularly in an amount of about
6.5 to 8.0 wt %. When the amount of the ester-based viscosity
modifier is less than about 3 wt %, performance of preventing wear
of the transmission may be reduced, and when the amount is greater
than about 10 wt %, since the viscosity at elevated temperatures
may substantially increase, fuel efficiency of vehicles may
deteriorate. Accordingly, the ester-based viscosity modifier may be
in an amount of about 3 to 10 wt %.
[0027] The additive, as used herein, may include one or more
selected from the anti-wear agent, the detergent dispersant, the
friction modifier, the extreme pressure additive, and the
anti-oxidant. The anti-wear agent may prevent wear between metals
and in particular, zinc dithiophosphate may be used as the
anti-wear agent, without limitation. The detergent dispersant may
be a metal system and disperse sludge, wear debris, and the like
generated in the transmission and thus reduce damage in lubrication
of parts. In particular, a bissuccinimide type ashless dispersant
may be used as the detergent dispersant, without limitation. The
friction modifier may maintain a static friction coefficient and a
kinetic friction coefficient so as to gear a synchronizer ring
without a crash. In particular, an ester phosphate-based compound
may be used as the friction modifier. The extreme pressure additive
may prevent fusion and wear of parts under a high load and a
polysulfide-based compound may be used as the extreme pressure
additive, without limitation. The anti-oxidant may prevent gelation
by oxidation of the oil and in particular, calcium sulfonate may be
used as the anti-oxidant, without limitation. The additive which
may has been generally be used in the art may be further included,
and may not be limited to the aforementioned examples.
[0028] The additive may be used in an amount of about 8 to 15 wt %
based on the total weight of the manual transmission oil
composition. When the amount of the additive is less than about 8
wt %, basic performance required as the transmission oil such as
endurance, a synchronizer ring friction property, and wear
prevention performance may be reduced thereby causing trouble in
the transmission. When the amount is greater than about 15 wt %,
corrosion of copper-based synchronizer ring parts may be promoted.
Accordingly, the additive may be used in an amount of about 8 to 15
wt %.
[0029] Moreover, the manual transmission oil composition may
further include polyalkyl methacrylate in an amount of about 3 to 5
wt % as the viscosity modifier based on the total weight of the
manual transmission oil composition.
[0030] In particular, the polyalkyl methacrylate viscosity modifier
may have a number average molecular weight of about 300,000 to
400,000 and about four to six C.sub.12 to C.sub.15 polymer chains.
The polyalkyl methacrylate viscosity modifier may suppress an
increase in viscosity at low temperatures. In addition, the
polyalkyl methacrylate viscosity modifier may be used in an amount
of about 3 to 5 wt % based on the total weight of the manual
transmission oil composition. when the amount of polyalkyl
methacrylate is less than about 3 wt %, the viscosity may not
appropriately increase at room temperature and elevated
temperatures and an excessive increase in viscosity may be caused
at low temperatures. When the amount is greater than about 5 wt %,
the viscosity may increase at both high and low temperatures and a
reduction of the viscosity due to shearing may be caused during an
endurance test thereby reducing endurance. Accordingly, the
polyalkyl methacrylate may be used in an amount of about 3 to 5 wt
% as described above.
[0031] The manual transmission oil formed of the resin composition
according to various exemplary embodiments of the present invention
may have an average kinematic viscosity of about 5 to 6 cSt at a
temperature of about 100.degree. C., the average kinematic
viscosity of 24 to 30 cSt at a temperature of about 40.degree. C.,
and the average absolute viscosity of about 4,000 to 10,000 cP at a
temperature of about -40.degree. C. Moreover, the manual
transmission oil may have the reduced viscosity as compared to
conventional manual transmission oils of which an average kinematic
viscosity is of about 7 to 15 cSt at a temperature of about
100.degree. C., an average kinematic viscosity is of about 45 to
100 cSt at a temperature of about 40.degree. C., an average
absolute viscosity of about 10,000 to 100,000 at a temperature of
about -40.degree. C., and gear endurance is of about 40 to 60 hr.
In particular, the manual transmission oil of the present invention
may secure endurance such as target gear endurance of about 80 to
200 hr of the transmission and improve fuel efficiency of vehicles
by 1 to 2%.
Examples
[0032] The following examples illustrate the invention and are not
intended to limit the same.
[0033] Hereinafter, the present invention will be described in more
detail through Examples. However, the Examples are set forth to
illustrate the present invention, but the scope of the present
invention is not limited thereto.
Examples 1 to 3 and Comparative Examples 1 to 4
[0034] The manual transmission oils of Examples 1 to 3 and
Comparative Examples 1 to 4 were manufactured according to the
composition and the content described in Table 1.
TABLE-US-00001 TABLE 1 Compositions and contents (unit: wt %)
Example Comparative Example Classification 1 2 3 1 2 3 4 Compo-
Base oil.sup.1) 84 83 80 87 75 75 75 sition (wt %) Polyalkyl 3 --
-- 3 -- 8 3 methacrylate viscosity modifier.sup.2) (wt %)
Ester-based 3 7 10 -- 15 7 12 viscosity modifier.sup.3) (wt %)
Additive 10 10 10 10 10 10 10 package.sup.4) (wt %) Total content
(wt %) 100 100 100 100 100 100 100 .sup.1)Eneos PAO4 (kinematic
viscosity at a temperature of about 100.degree. C.: about 3.9 cSt;
viscosity index: 130; pour point: -69.degree. C.) .sup.2)87725
manufactured from Lubrizol Corp. .sup.3)MERIDIAN .TM. manufactured
from Lubrizol Corp. .sup.4)Anglamol 2141 manufactured from Lubrizol
Corp. which includes an anti-wear agent, a detergent dispersant, a
friction modifier, an extreme pressure additive, and an
anti-oxidant
Test Example
Measurement of Physical Properties
[0035] Physical properties of the manual transmission oils
manufactured according to Examples 1 to 3 and Comparative Examples
1 to 4 were measured by the following method, and the physical
property values are described in Table 2. [0036] (1) Measurement
method of the kinematic viscosity: The kinematic viscosity was
measured by using standard ASTM D 445 measurement method.
[0037] (2) Measurement method of the low temperature viscosity: The
low temperature viscosity was measured by using standard ASTM D
2983 measurement method.
[0038] (3) FZG gear endurance test: FZG gear endurance was measured
by using standard FVA No. 2/IV measurement method.
[0039] (4) Differential endurance test: Endurance of the
differential gear and the ring gear were evaluated by applying the
real-vehicle load having the level of about 300,000 km under the
driving condition where the differential gear was operated.
[0040] (5) Power train endurance test: The actual engine and
transmission were equipped to apply the load to each gear-shifting
stage under the real-vehicle driving condition of the level of
about 300,000 km and thus evaluate endurance.
[0041] (6) Constant speed endurance test: The fixed speed and
torque were given for each stage by using the motor dynamometer to
evaluate endurance.
[0042] (7) Measurement method of transferring efficiency (%) of the
transmission: The ratio of power inputted into the transmission and
power outputted from the transmission were measured.
TABLE-US-00002 TABLE 2 Measurement result of physical properties
Target Example Comparative Example Classification Unit value 1 2 3
1 2 3 4 Test Kinematic 100.degree. C. cSt 5.3 to 6.0 5.3 5.4 6.0
5.3 11.5 13.2 12.8 result viscosity 40.degree. C. cSt 23 to 30 23
25 30 23 49 59 62 Low -40.degree. C. cP 4000 to 10000 4,000 5,000
10,000 4,000 13,000 25,000 30,000 temperature viscosity FZG gear
endurance hr 90 to 200 90 120 200 50 140 140 180 Transmission
Differential -- There are no OK OK OK NG OK OK OK endurance pitting
and Power train -- abnormal wear OK OK OK OK OK OK OK endurance in
parts such Constant -- as gears and OK OK OK NG OK OK OK speed
bearings (OK) endurance Transferring % 96 or more 97 97 96 97 95 94
93 efficiency
[0043] As described in Table 2, the manual transmission oil
compositions of Examples 1 to 3 had the average kinematic viscosity
of about 5 to 6 cSt at a temperature of about 100.degree. C., the
average kinematic viscosity of about 24 to 30 cSt at a temperature
of about 40.degree. C., and the average absolute viscosity of about
4,000 to 10,000 cP at a temperature of about -40.degree. C. In
addition, the manual transmission oil compositions of Examples 1 to
3 had the substantially reduced viscosity as compared to
Comparative Examples while exhibiting improved results of pitting
endurance of about 90 hr or greater as the FZG gear endurance test
result. Moreover, the manual transmission oil compositions of
Examples 1 to 3 had transferring efficiency of the transmission
maintained at about 96% or greater and no abnormality was detected
in the endurance test.
[0044] According to various exemplary embodiments of the present
invention, the manual transmission oil compositions, for example,
Examples 1 to 3, may have substantially reduced viscosity and have
improved endurance of the transmission. Also, effectiveness of fuel
efficiency was enhanced by about 1 to 2% due to the manual
transmission oil compositions.
[0045] Accordingly, the manual transmission oil composition of the
present invention may be advantageous by reducing the viscosity,
and further by improving wear resistance of the transmission, and
an oil film formed therein may be enlarged to improve gear
pitting/scoring and enhance fuel efficiency.
[0046] The invention has been described in detail with reference to
exemplary embodiments thereof. However, it will be appreciated by
those skilled in the art that changes may be made in these
embodiments without departing from the principles and spirit of the
invention, the scope of which is defined in the appended claims and
their equivalents.
* * * * *