[0001] The present disclosure, in general, relates to an apparatus for cooling
brakes of a motor vehicle, and particularly to cooling apparatus having a circular
5 contour that provides effective cooling of the disc brakes of the motor vehicle.
BACKGROUND
[0002] In brake systems, almost all vehicles are fitted with disc brakes. These
disc brakes essentially use a pair of the metallic disc called the brake disc and brake
pads [a cake of friction material] to achieve the desired braking effect. Whenever
10 brakes of a vehicle are applied either at the high speed or the low speed, brake pads
rub against the metallic brake disc and results in the generation of a brake force.
The work done by this brake force is to decrease the kinetic energy of a vehicle and
dissipate this kinetic energy in the form of heat energy.
[0003] Further, during the operation of the vehicle brakes, generally at the
15 lower speeds, when the brake pads are applied frequently to the brake disc due to
traffic congestion and traffic signal, a huge amount of heat is produced at the brake
disc. This build-up heat cannot be easily transferred to the atmosphere as there is
no forced circulation of air.
[0004] By the action of heat generated at brake disc, the temperature near the
20 brake disc increases and may reach as high as 500 degrees celsius. High
temperatures are detrimental to brake performance and may lead to issues such as
fading of the brake pads, phenomena which causes loss of braking effect, red hot
brake disc, and may also compromise dimensional stability which may lead to
undesirable effects such as brake pulling, brake judder, brake noise, etc. In order to
25 counter these effects, the brake disc must be cooled with a high rate of heat loss.
[0005] A complication associated with this build-up of heat is that the heated
air surrounding the brake disc decreases the rate of cooling of brake disc. Moreover,
3
the air surrounding the brake disc is warmer than the ambient temperature resulting
in the stagnation of the heated air above and behind the wheel assembly, thus
requiring specialized outlets for ventilation in order to increase the rate of cooling
of brake disc.
5 [0006] However, the more serious concern resulting from overheated brake disc
is that the braking surfaces experience a reduction in brake force. The loss in brake
force, also known as brake fade, occurs more often during both high-performance
driving as well as slow driving, i.e., frequent application of brakes due to traffic
congestion, and during long steep downhill routes where vehicles are constantly
10 applying the brakes.
[0007] Various approaches have been made in the state of the art to overcome
these problems to assist in brake disc cooling. These approaches include ventilated
brake disc, fan blades, and especially designed wheel that help in dissipating the
heat generated and transfer to the ambient air.
15 [0008] One approach includes blasting of fresh air onto the brake disc. For this,
air ducts are placed in the front of the vehicle to generate a stream of fresh air.
However, this worsens the problem with respect to aerodynamics.
[0009] Another approach discloses an innovation that helps in ventilating the
brake disc itself. Like the air ducts mentioned above, this approach also discloses
20 an innovation that assists in cooling of the brake disc, but complicates the
aerodynamics problem as the air vented from the brake disc is simply pushed into
the high-pressure air pocket around the wheel assembly.
[0010] After recognizing this problem, manufacturers have created air vents
typically located above and behind the wheel that helps in eliminating the high25 pressure air pocket. The combination of the air ducts, the ventilated brake discs, and
the air vents above and behind the wheel generally resolve the brake fade issue.
However, these devices are structurally integrated into the vehicle and cannot be
readily and significantly changed. Also, adjustments to the air ducts and the air
4
vents for cooling of brake disc can be made by simply taping the openings of these
channels. However, such changes to a brake cooling system are rudimentary and
extremely limited. To adjust the airflow patterns via these channels (ducts and/or
vents), the vehicle must again be taken into the garage since the car body shell must
5 be removed in order to access and/or change the air ducts and the air vents for
cooling of brake disc.
[0011] Yet another approach defines fins in brake disc that provide an increased
rate of cooling; however, based on market experience, it has been observed that in
some cases, fins in the brake disc are not sufficient and may lead to increased
10 temperature during braking.
[0012] Yet another approach describes the use of wheels and wheel accessories
(particularly wheel trims, disc brake hat, and wheel fairings) to ventilate the brake
disc. Each of these has significant limitations. One common limitation among these
wheel-related brake-cooling devices is that the airflow generated by these devices
15 is limited to a single outward direction. In other words, these wheel-related devices
make no use of the brake vent system. Wheel-related devices are also not stackable.
For all practical purposes, a vehicle cannot support more than one wheel on a disc
brake hat or support more than one-wheel accessory on a wheel.
[0013] Also, the wheel accessories, and the wheels to a lesser extent, are
20 relatively inefficient at drawing the air away from the brake disc because of the gap
distance and the structural obstructions, i.e., the wheel itself, between the brake disc
and the wheel accessories. Therefore, wheel accessories merely draw out the air
from the wheel assembly area without actively pushing the air out.
[0014] Therefore, it is desirable to provide a relatively inexpensive, light25 weighted and efficient brake cooling system that is adjustable and readily
accessible. Such a brake cooling system should be suited for all driving conditions.
OBJECTS OF THE DISCLOSURE
5
[0015] Some of the objects of the present disclosure, which at least one
embodiment herein satisfy, are listed hereinbelow.
[0016] It is a general or primary object of the present disclosure to provide a
disc brake cooling apparatus.
5 [0017] It is another object of the present disclosure to provide a disc brake
cooling apparatus that is relatively inexpensive, light- weighted and readily
adjustable or accessible.
[0018] It is yet another object of the present disclosure to provide a disc brake
cooling apparatus that is suited for both the high performance as well as for the slow
10 driving.
[0019] These and other objects and advantages will become more apparent
when reference is made to the following description and accompanying drawings.
SUMMARY
[0020] This summary is provided to introduce concepts related to a disc brake
15 cooling apparatus for a motor vehicle having a wheel with a disc brake hat, a disc,
and a disc brake assembly. Moreover, the proposed structure of the disc brake
cooling apparatus has two sets of orientally opposite vanes, in which the first set of
vanes cools an outer face of a brake disc and the second set of vanes cools an inner
face of the brake disc. The concepts are further described below in the detailed
20 description. This summary is not intended to identify key features or essential
features of the claimed subject matter, nor is it intended to be used to limit the scope
of the claimed subject matter.
[0021] The disc braking cooling apparatus for a motor vehicle comprising a
first circular band, a second circular band, and a third circular band, arranged
25 concentrically with respect to one another. Further, a first set of vanes connecting
the first circular band, and the second circular band, and a second set of vanes
6
connecting the second circular band and the third circular band. The first set of
vanes are orientally opposite to the second set of vanes.
[0022] In an aspect, the first set of vanes are convex shaped curved vanes when
viewed from a front side of the brake cooling apparatus.
5 [0023] In an aspect, the second set of vanes are concave shaped curved vanes
when viewed from a front side of the brake cooling apparatus.
[0024] In an aspect, the first set of vanes are placed at an angle ranges in
between 20 to 40 degrees.
[0025] In an aspect, the second set of vanes are also placed at an angle ranges
10 in between 20 to 40 degrees but with different orientations.
[0026] In an aspect, the diameter of the second circular band is equal to an
outer diameter of a disc of the disc brake.
[0027] In an aspect, the first set of vanes directs the airflow from vehicle outside
towards the outer brake disc face of the disc brake.
15 [0028] In an aspect, the second set of vanes directs the airflow from the inner
brake disc face of the disc brake towards vehicle outside.
[0029] In an aspect, the disc brake cooling apparatus is made of engineering
resin.
[0030] In an aspect, the brake cooling apparatus is flexible enough to be
20 mounted on the inner housing of the wheel either through press-fitting or fastening
means such as key-slot arrangements.
[0031] In an aspect, the disc brake cooling apparatus is secured onto the disc
brake hat on the front side of the brake disc rather than within the disc brake
assembly that helps in easy removal of the brake-cooling device if required.
7
[0032] In an aspect, the disc brake cooling apparatus is also designed in such a
way that it is easily attached or detached with other wheel accessories without
interfering with the operation of the wheel (e.g., some embodiments of the invention
do not require the wheel offsets to be changed) or disc brake assembly.
5 [0033] In an aspect, the flexibility provided by the disc brake cooling apparatus
allows rapid adjustments to a brake cooling system, which can be vital both at low
and high speeds. For example, sometimes a brake duct can suffer a blockage both
either at low or high speeds of vehicle, which creates an unequal temperature
distribution in the brake disc. Under those circumstances, the cooling apparatus can
10 be mounted on the disc brake hat or can be press-fitted inside the wheel to divert
the airflow back to the brake disc. The cooling apparatus can also be altered,
removed, or replaced as the need arises.
[0034] Additionally, since the cooling device is located on the easily accessible
disc brake hat, adjustments to the cooling device (e.g., adding, removing, or
15 replacing the brake cooling structure) can be made without heavy equipment. This
means that the cooling device can be adjusted even in remote locations and the
harsh conditions frequently encountered by vehicle drivers. The present invention
thus allows vehicle drivers to make changes to the cooling device just before
reaching steep downgrades, even if there is no service garage in that area.
20 [0035] Various objects, features, aspects, and advantages of the inventive
subject matter will become more apparent from the following detailed description
of preferred embodiments, along with the accompanying drawing figures in which
like numerals represent like components.
BRIEF DESCRIPTION OF THE DRAWINGS
25 [0036] The illustrated embodiments of the subject matter will be best
understood by reference to the drawings, wherein like parts are designated by like
numerals throughout. The following description is intended only by way of
8
example, and simply illustrates certain selected embodiments of devices, systems,
and methods that are consistent with the subject matter as claimed herein, wherein:
[0037] FIG. 1 illustrates a front view of the brake cooling apparatus viewed
from outside of the vehicle, in accordance with an embodiment of the present
5 disclosure;
[0038] FIGS. 2A-2C illustrate an enlarged cross-sectional views of the brake
cooling apparatus that is placed in between the wheel and the brake disc, in
accordance with an embodiment of the present disclosure;
[0039] FIG. 3 illustrates an assembly section view detailing the airflow of the
10 brake cooling apparatus, in accordance with an embodiment of the present
disclosure;
[0040] FIG. 4A illustrates an isometric view of the brake cooling apparatus, in
accordance with an embodiment of the present disclosure;
[0041] FIG. 4B illustrates a disc brake of the vehicle;
15 [0042] FIG. 4C illustrates the joining of the brake cooling apparatus and the
disc brake, in accordance with an embodiment of the present disclosure;
[0043] FIG. 5 illustrates an exploded view of the complete assembly showing
the installation of a wheel, the brake cooling apparatus and the brake disc along
with brake pads, in accordance with an embodiment of the present disclosure;
20 [0044] FIG.6 illustrates a graphical representation of improved cooling of the
brake assembly by using the brake cooling apparatus, in accordance with an
embodiment of the present disclosure.
DETAILED DESCRIPTION
[0045] The following is a detailed description of embodiments of the disclosure
25 depicted in the accompanying drawings. The embodiments are in such detail as to
9
clearly communicate the disclosure. However, the amount of detail offered is not
intended to limit the anticipated variations of embodiments; on the contrary, the
intention is to cover all modifications, equivalents, and alternatives falling within
the spirit and scope of the present disclosure as defined by the appended claims.
5 [0046] As used in the description herein and throughout the claims that follow,
the meaning of “a,” “an,” and “the” includes plural reference unless the context
clearly dictates otherwise. Also, as used in the description herein, the meaning of
“in” includes “in” and “on” unless the context clearly dictates otherwise.
[0047] The present disclosure aims to provide a brake cooling apparatus having
10 a circular contour that effectively cools a disc brake installed in a vehicle. The
proposed disc brake cooling apparatus having two sets of orientally opposing vanes
that suck air from inwards of the vehicle and discharge it outside and vice-versa
true for another set of vanes. The structure of the disc brake cooling apparatus
serves two major functions- the first one is the effective cooling of both the faces
15 of the brake disc and the second one is the effective replacement of the warm air by
the cold air.
[0048] FIG. 1 shows a front view of a brake cooling apparatus (100) viewed
from the outside of a vehicle, in accordance with an exemplary embodiment of the
present disclosure. The brake cooling apparatus (100) having circular contour
20 comprising a first circular band (102) with a diameter (D1), a second circular band
(104) with a diameter (D2) and a third circular band (106) with a diameter (D3). As
can be seen from FIG. 1, the first circular band (102), the second circular band
(104), and the third circular band (106) are arranged concentrically with respect to
one another.
25 [0049] The diameter (D1) of the first circular band (102) is larger than the outer
diameter (Dh2) of a disc brake hat (204), i.e., D1>Dh2, that facilitates in the easy
fitment of the brake cooling apparatus (100) over the disc brake hat (204).
Moreover, FIG. 1 also shows the mounting of the brake cooling apparatus (100) on
the brake disc (210).
10
[0050] As can be seen from FIG. 1, a first set of vanes (108) connects the first
circular band (102) and the second circular band (104), and a second set of vanes
(110) connects the second circular band (104) and the third circular band (106). In
an aspect, the first set of vanes (108) are orientally opposite to the second set of
5 vanes (110).
[0051] FIGS. 2A-2C show enlarged views of the brake cooling apparatus (100)
placed in between a wheel (400) and the brake disc (210). FIGS. 2A-2C show the
various views that clearly illustrate the various components inside the disc brake
assembly and the brake cooling apparatus (100).
10 [0052] The assembly or structure of the brake cooling apparatus (100) is
designed in such a way that the brake cooling apparatus (100) can easily be
assembled inside an inner periphery of the wheel (400) either through press-fitting
and/or key slot arrangement. FIG. 2B clearly shows the interference fit (500)
between the brake cooling apparatus (100) and the wheel (400) that can be achieved
15 by press-fitting the brake cooling apparatus (100) inside the wheel (400). Section
(502) shows the clearance between the surrounding parts and the brake cooling
apparatus (100). Moreover, no part of the structure is projected outside the wheel
(400).
[0053] FIGS. 2A, 2B, and 2C clearly show the design of the structure of the
20 brake cooling apparatus (100) that rotates with the wheel (400) to provide the fan
effect on the brake disc (210) to achieve the desired disc cooling.
[0054] FIG. 3 shows the assembly section view detailing the airflow of the
brake cooling apparatus (100) in accordance with an embodiment of the present
disclosure. The shape of the brake cooling apparatus (100) creates three types of
25 airflows, Flow 1, Flow 2, Flow 3, for effective cooling as described below.
[0055] In Flow 1, when the brake cooling apparatus (100) rotates along with
the wheel (400), the second set of vanes (110) create a pressure difference across
the vanes and suck air from inside of the vehicle and discharge it to outside. On its
11
way towards the second set of vanes (110), cooler air flows over the inner hot face
(206) of the brake disc (210) and carries heat with itself and becomes hot. This hot
air is rejected from the second set of vanes (110) to outside of the vehicle. This
results in an increased rate of heat dissipation from the inner hot face (206) of the
5 brake disc (210) and the desired cooling effect on the inner face (206) of the disc
brake (210).
[0056] In Flow 2, the first set of vanes (108) perform the opposite function and
are responsible for the cooling of the outer face (208) of the brake disc (210). The
first set of vanes (108) suck cooler air from environment and projects directly on
10 hot outer face (208) of the brake disc (210), collecting heat, this air becomes hot
and is rejected from the second set of vanes (110).
[0057] In Flow 3, the second set of vanes (110) perform an additional function
to increase convection cooling by rejecting hot air that came out of inner fins of
brake disc through the second set of vanes (110) to the environment.
15 [0058] Moreover, the second set of vanes (110) has to deal with a higher mass
flow rate than the first set of vanes (108), hence the area of the second set of vanes
(110), radial and circumferential, is kept more than the first set of vanes (108).
[0059] FIG. 4A shows an isometric view of the brake cooling apparatus (100)
for a motor vehicle having circular contour comprising a first circular band (102),
20 a second circular band (104), and a third circular band (106) arranged
concentrically. The first set of vanes (108) connects the first circular band (102) and
the second circular band (104) and the second set of vanes (110) connects the
second circular band (104) and the third circular band (106). The first set of vanes
(108) are positioned orientally opposite to the second set of vanes (110). The first
25 set of vanes (108) are convex shaped curved vanes when viewed from a front side
of the brake cooling apparatus (100). The second set of vanes (110) are concave
shaped curved vanes when viewed from a front side of the brake cooling apparatus
(100). The first set of vanes (108) and the second set of vanes (110) are placed at
an angle of 20 to 40 degrees. In an alternative embodiment, the first set of vanes
12
(108) can be concave shaped curved vanes and the second set of vanes (110) can be
convex shaped curved vanes.
[0060] FIG. 4B shows the disc brake assembly (200) comprising the brake disc
(210) having the inner surface (206) and the outer surface (208). The disc brake
5 assembly (200) also includes the brake disc hat (204) having a plurality of holes
that are used to connect to the wheel (400). Additionally, the diameter (D2) of the
second circular band (104) is equal to an outer diameter (Dd2) of a brake disc (210)
having a brake caliper (202) with brake pads. The brake cooling apparatus (100) is
assembled inside the inner periphery of the wheel (400) through press-fitting or key
10 slot arrangement. Alternatively, it can also be mounted on the brake disc (210) or
the brake disc hat (204).
[0061] FIG. 4C shows a joining process of the brake cooling apparatus (100)
and the disc brake assembly (200). FIG. 4C clearly shows that the diameter (D1)
of the first circular band (102) of the brake cooling apparatus (100) is larger than
15 the outer diameter (Dh2) of the disc brake hat (204), i.e., D1>Dh2, that facilitate in
the easy fitment of the brake cooling apparatus (100) over the disc brake hat (204).
FIG. 4C also shows that the diameter (D2) of the second circular band (104) is
equal to an outer diameter (Dd2) of a brake disc (210) of the disc brake, so as to
ensure that the outer surface (208) of the brake disc (210) is sufficiently cooled by
20 the first set of vanes (108) formed in between the first circular band (102) and the
second circular band (104).
[0062] FIG. 5 shows an exploded view of the complete assembly showing the
installation of the wheel (400), the brake cooling apparatus (100) and the brake disc
(210) along with the brake caliper (202) having brake pads. The exploded view
25 clearly shows the brake cooling apparatus (100) that is used as part of an
embodiment of the present disclosure. The disc brake hat (204) and the wheel (400)
are secured together by lug nuts (not shown) and wheel bolts (not shown) as the
plurality of holes are provided on both the disc brake hat (204) and the wheel (400).
The brake cooling apparatus (100) is assembled in the inner periphery of the wheel
13
(400) through press-fitting and/or key slot arrangement. Alternatively, in an aspect,
there could be a provision for mounting the brake cooling apparatus (100) on the
brake disc (210). During the operation of the motor vehicle, the brake cooling
apparatus (100) rotates along with the rotation of the wheel (400). As the brake
5 cooling apparatus (100) rotates, the first set of vanes (108) pushes the fresh air
inside to cool the outer face (208) of the brake disc (210) and the second set of
vanes (110) pulls out the hot air from and around the inner face (206) of the brake
disc (210) that results in the effective cooling of both the surfaces (206, 208) of the
brake disc (210).
10 [0063] FIG. 6 illustrates a graph that clearly shows the improvement in cooling
by effectively utilizing the brake cooling apparatus (100) of the present disclosure.
In accordance with an embodiment of the present disclosure, the brake cooling
apparatus (100) performance target is decided based on a successive increase in
temperature in repetitive braking.
15 [0064] In the graph as shown in FIG. 6, 1, 2, and 3 represent one braking cycle.
Steps 1-2 represent braking (brake pedal pressed) where temperature increases and
steps 2-3 represent cooling of brakes after the brake pedal is released. Step 3
represents temperature just before the next braking event. The difference between
the temperature at the step 3 and the temperature at the step 1 represents the total
20 increase in temperature of disc brake in a single braking event. Using the brake
cooling apparatus (100) proposed herein, the target is to achieve temperature at step
3 as close as possible to step 1, denoted as ‘targeted cooling’ in the graph.
[0065] In square bullets steps 1ʹ, 2ʹ, and 3ʹ represent the corresponding braking
event where the difference between final and the initial temperature is very less,
25 denoted as ‘achieved cooling’ in the graph. As can be seen from the graph, with the
implementation of the brake cooling apparatus (100) proposed herein, repetitive
braking shows that overall disc brake temperature has come down significantly and
operating range is reduced from Tmax – Tmin to T’max – Tmin. For instance, when the
brake cooling apparatus (100) is not implemented, Tmax could reach around 500
14
degrees celsius from Tmin of atmospheric temperature. However, after
implementation of the brake cooling apparatus (100), Tmax may decrease to 250
degrees Celcius from Tmin of atmospheric temperature. This clearly shows that the
overall cooling of the disc brake is achieved by the implementation of the brake
5 cooling apparatus (100) proposed herein.
[0066] Additionally, to achieve the target cooling, in the brake cooling
apparatus (100) proposed herein, seven number of vanes, i.e., in both the first as
well as the second set of vanes, is found to be suitable. Those skilled in the art can
appreciate that the number of vanes and angle of positioning of the vanes are
10 variable and will depend upon several factors of design including, but not limited
to, targeted cooling, wheel diameter, disc diameter, strength and packaging
constraints, and so forth.
[0067] Further, it will be appreciated that those skilled in the art will be able to
devise various arrangements that, although not explicitly described or shown
15 herein, embody the principles of the invention and are included within its scope.
[0068] Furthermore, all examples recited herein are principally intended
expressly to be only for pedagogical purposes to aid the reader in understanding the
principles of the invention and the concepts contributed by the inventor(s) to
furthering the art and are to be construed as being without limitation to such
20 specifically recited examples and conditions. Also, the various embodiments
described herein are not necessarily mutually exclusive, as some embodiments can
be combined with one or more other embodiments to form new embodiments.
[0069] While the foregoing describes various embodiments of the invention,
other and further embodiments of the invention may be devised without departing
25 from the basic scope thereof. The scope of the invention is determined by the claims
that follow. The invention is not limited to the described embodiments, versions or
examples, which are included to enable a person having ordinary skill in the art to
make and use the invention when combined with information and knowledge
available to the person having ordinary skill in the art.
15
ADVANTAGES
[0070] The proposed brake cooling structure has significant advantages from
current design:
5 Effective cooling of brake disc by generating airflow on both brake disc faces.
 Additional increase in cooling effectiveness of ventilated disc by increasing the
airflow through vanes.
 Effective packaging in brakes with minimum design modification.
 Decrease in overall operating temperature range during repeated braking (as shown
10 in Graph)
 Improved brake pad life due to the reduction in disc temperature.
 Decreased likelihood of phenomenon such as brake judder, noise, pulling, red hot
disc, etc.

We claim:
1. A disc brake cooling apparatus (100) for a motor vehicle having circular
contour, comprising:
a first circular band (102), a second circular band (104), and a third circular
5 band (106), wherein the first circular band (102), the second circular band (104),
and the third circular band (106) are being arranged concentrically;
a first set of vanes (108) connecting the first circular band (102) and the
second circular band (104); and
a second set of vanes (110) connecting the second circular band (104) and
10 the third circular band (106),
wherein the first set of vanes (108) are orientally opposite to the second set
of vanes (110).
2. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
first set of vanes (108) are convex shaped curved vanes when viewed from a front
15 side of the brake cooling apparatus (100).
3. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
second set of vanes (110) are concave shaped curved vanes when viewed from a
front side of the brake cooling apparatus (100).
4. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
20 first set of vanes (108) are placed at an angle of 20 to 40 degrees.
5. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
second set of vanes (110) are placed at an angle of 20 to 40 degree
6. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
diameter (D2) of the second circular band (104) is equal to an outer diameter (Dd2)
25 of a disc (210) of a disc brake (200).
17
7. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
first set of vanes (108) directs the airflow towards the outer brake disc face (208)
of a disc brake (200).
8. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
5 second set of vanes directs the airflow away from the inner brake disc face (206) of
a disc brake (200).
9. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
disc brake cooling apparatus (100) is assembled inside inner periphery of a wheel
(400) through one of a press-fitting and key slot arrangement.
10 10. The disc brake cooling apparatus (100) as claimed in claim 1, wherein the
disc brake cooling apparatus (100) is mounted on one of a brake disc (210) and a
brake disc hat (204).