TECHNICAL FIELD OF INVENTION
The invention, in general, relates to emergency brake release system for commercial
vehicles.
BACKGROUND OF INVENTION
Air brake systems are used in vehicles, such as trucks, and buses, for rendering
braking operations. Such systems typically includes service brakes and parking brakes having
a brake pedal, a hand control valve, and an air storage tank as primary constituents. The
parking brake includes a disc or drum brake arrangement that affects braking in vehicles
when held in an 'applied' position by using spring pressure. The parking brake is usually
facilitated by the hand control valve while the service brake is controlled by the brake pedal.
The service brake is applied when a driver steps on the brake pedal. This releases air from the
air storage tank thereby applying pressure on a brake chamber and achieving the braking
action. The air in the air storage tank is powered and maintained by a vehicle engine.
In certain cases, for example, when the vehicle engine may fail or stall, air pressure
will start to decrease and will continue to do so until complete air pressure loss occurs. As a
result, inadvertent engagement of the brakes (both the service brakes and parking brakes)
occurs and the vehicle will ultimately stop. Until a time the air pressure is restored, the brakes
remain engaged and mobility of the vehicle is restricted.
Major problem arises when the vehicle is running on a busy road/highway and all of a
sudden the vehicle engine gets ceased. For example, during monsoon season, owing to
waterlogging, water may enter inside the vehicle engine and may lead to engine seizure or
engine failure. As a result, a complete air pressure loss may occur and the brakes may
inadvertently get engaged. Stalling of the vehicles on such highways/busy roads may result in
traffic jams and affects traffic in certain cases, sudden jamming of brakes may also prove to
be fatal for the occupants of the vehicle.
Thus, there is a need for a solution that overcomes the above deficiencies.
SUMMARY OF INVENTION
This summary is provided to introduce a selection of concepts in a simplified format
that is further described in the detailed description of the invention. This summary is not
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intended to identify key or essential inventive concepts of the claimed invention, nor is it
intended for determining the scope of the claimed invention.
According to an aspect of the present invention, an emergency brake release system is
provided. In an example, the emergency brake release system comprises a double check
valve, a non-return valve, and a relay valve. The double check valve defines a first input port,
a second input port, and an output port. The first input port may be coupled to a primary air
source and the output port may be coupled to at least one spring brake actuator. The nonreturn
valve defines an input port and an output port. The output port of the non-return valve
is connected to the second input port of the double check valve and also to the supply port of
the relay valve; and the input port of the non-return valve may be coupled to an auxiliary air
source. The relay valve is connected between the output port of the non-return valve and the
output port of the hand control valve. Accordingly, the emergency brake release system can
operate in three modes such that:
a. in a first mode of operation defined by the primary air source supplying air at
a first predetermined amount of air pressure to the at least one spring brake
actuator, the double check valve couples the primary air source to the at least
one spring brake actuator;
b. in a second mode of operation defined by a reduction in an amount of air
pressure supplied by the primary air source to about 0 bar, the double check
valve couples the auxiliary air source to the at least one spring brake actuator;
and the auxiliary air source supplies air at a second predetermined air pressure
to the at least one spring brake actuator; and
c. in a third mode of operation defined by at least a partial restoration in an
amount of air pressure supplied by the primary air source, the relay valve
vents at least the air between the second input port of the double check valve
and the output port of the non-return valve. Further, in said mode, the double
check valve couples the primary air source to the at least one spring brake
actuator.
In an implementation, the relay valve defines a first input port, a second input port,
and a venting port. The first input port is coupled to the primary air and the second input port
is connected between the output port of the non-return valve and the second input port of the
double check valve.
In an implementation, the first predetermined amount of air pressure is a minimum of
4.7 bar.
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In an implementation, the second predetermined amount of air pressure is a minimum
of 4.7 bar.
In an implementation, the double check valve is a high pressure valve.
In an implementation, the primary air source is a hand control valve.
In an implementation, the auxiliary air source is at least one tyre of a vehicle.
Following are the advantages of the claimed invention:
a. Useful when the mechanic release system is not accessible.
b. The existing air brake system in the field of automobiles has been improvised
and designed to facilitate the vehicle movement in case of engine failure or
complete air pressure loss in the system.
c. To avoid traffic congestion or vehicle queuing.
d. To prevent unwanted delays.
e. To reduce manpower effort.
f. To make the overall system automated.
g. Towing of the vehicle in case of engine failure can be easily carried out.
h. To improve system overall efficiency.
The details of one or more embodiments are set forth in the accompanying drawings
and description below. Other features and advantages will be apparent from a reading of the
following detailed description and a review of the associated drawings. It is to be understood
that the following detailed description is explanatory only and is not restrictive of the
invention as claimed.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
To clarify the advantages and features of the invention, a more particular description
of the invention will be rendered by reference to specific embodiments thereof, which are
illustrated in the appended drawings. It is appreciated that these drawings depict only typical
embodiments of the invention and are therefore not to be considered limiting of its scope. The
invention will be described and explained with additional specificity and detail with the
accompanying drawings, in which:
Figure 1 illustrates an exemplary emergency brake release system, according to an
embodiment of the present subject matter;
Figure 2a and Figure 2b illustrates the exemplary emergency brake release system,
according to another embodiment of the present subject matter; and
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Figure 3 illustrates the exemplary emergency brake release system, according to
another embodiment of the present subject matter.
It may be noted that to the extent possible like reference numerals have been used to
represent like elements in the drawings. Further, those of ordinary skill in the art will
appreciate that elements in the drawings are illustrated for simplicity and may not have been
necessarily drawn to scale. For example, the dimensions of some of the elements in the
drawings may be exaggerated relative to other elements to help to improve understanding of
aspects of the invention. Furthermore, the one or more elements may have been represented
in the drawings by conventional symbols, and the drawings may show only those specific
details that are pertinent to understanding the embodiments of the invention so as not to
obscure the drawings with details that will be readily apparent to those of ordinary skill in the
art having the benefits of the description herein.
DETAILED DESCRIPTION
For the purpose of promoting an understanding of the principles of the invention,
reference will now be made to the embodiments illustrated in the drawings and specific
language will be used to describe the same. It will nevertheless be understood that no
limitation of the scope of the invention is thereby intended, such alterations and further
modifications in the illustrated system, and such further applications of the principles of the
invention as illustrated therein being contemplated as would normally occur to one skilled in
the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description
and the following detailed description are exemplary and explanatory of the invention and are
not intended to be restrictive thereof. Throughout the patent specification, a convention
employed is that in the appended drawings, like numerals denote like components.
Reference throughout this specification to “an embodiment”, “another embodiment”
or similar language means that a particular feature, structure, or characteristic described in
connection with the embodiment is included in at least one embodiment of the invention.
Thus, the appearances of the phrase “in an embodiment”, “in another embodiment” and
similar language throughout this specification may, but do not necessarily, all refer to the
same embodiment.
The terms "comprises", "comprising", or any other variations thereof, are intended to
cover a non-exclusive inclusion, such that a process or method that comprises a list of steps
does not include only those steps but may include other steps not expressly listed or inherent
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to such process or method. Similarly, one or more devices or sub-systems or elements or
structures proceeded by "comprises. a" does not, without more constraints, preclude the
existence of other devices or other sub-systems.
Air brake systems are implemented in vehicles, such as truck and buses for rendering
braking functionality in the vehicles. Parking brakes in the vehicles is achieved through a
spring provided in a spring brake actuator(s). The spring, when in an expanded state, results
in the application of brakes. Owing to various reasons, for example, due to engine seizure,
loss of air pressure in such air brake systems may occur. During and/or after air pressure loss,
spring brake actuators expand automatically. As a result, the spring expansion takes place
which further leads to inadvertent engagement of the brakes. In such a case, until a time the
air pressure is restored, the brakes remain engaged. In other words, the brakes get jammed.
As a result, the vehicle’s mobility is restricted.
Aspects of the present subject matter describe an emergency brake release system for
vehicles, such as trucks, buses, and the like. During situations where jamming of brakes
occurs in the vehicles, the emergency brake release system operates to release the jammed
brakes.
Various embodiments of the present subject matter will be described below in detail
with reference to the accompanying drawings.
Figure 1 illustrates an exemplary emergency brake release system (100) for a
commercial vehicle, according to an embodiment of the present subject matter. The
emergency brake release system (100) includes a double check valve (101), a non-return
valve (102), a relay valve (103), a primary air source (104), an auxiliary air source (105), and
at least one spring brake actuator (106). In an implementation, the double check valve (101)
is a high pressure valve. In an implementation, the primary air source (104) is a hand control
valve. In an implementation, the auxiliary air source (105) is at least one tyre of the
commercial vehicle.
The double check valve (101) defines a first input port (107), a second input port
(108), and an output port (109). In said example, the first input port (107) may be coupled to
the primary air source (104) and, the output port (109) may be coupled to the at least one
spring brake actuator (106).
The non-return valve (102) defines an input port (110) and an output port (111). In an
example, the output port (111) is connected to the second input port (108) of the double
check valve (101). Furthermore, the input port (110) may be coupled to the auxiliary air
source (105).
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In an example, the relay valve (103) may be connected between the output port (111)
of the non-return valve (102) and the second input port (108) of the double check valve (101).
In an example, the relay valve (103) defines a first input port (112), a second input port (113)
and a venting port (114). In said example, the first input port (112) may be coupled to the
primary air source (104). Furthermore, the second input port (113) is connected between the
output port (111) of the non-return valve (102) and the second input port (108) of the double
check valve (101).
The emergency brake release system (100) operates in three modes. A first mode of
operation is defined when the primary air source (104) supplies air at a first predetermined
amount of air pressure to the at least one spring brake actuator.
A second mode of operation is defined when there is a reduction in the amount of air
pressure supplied by the primary air source.
A third mode of operation is defined when there is a partial restoration in the amount
of air pressure supplied by the primary air source
Accordingly, during the first mode of operation, the double check valve (101) couples
the primary air source (104) to the at least one spring brake actuator (106). Subsequently, the
primary air source (104) provides a first predetermined air pressure to the at least one spring
brake actuator (106) (indicated by the solid lines in figure 1). Based on the provided first
predetermined air pressure, springs housed in the at least one spring brake actuator (106)
contracts. As a result, emergency brakes are released. In an implementation, the first
predetermined air pressure is a minimum of 4.7 bar.
Figure 2a & Figure 2b illustrates the exemplary emergency brake release system
(100), according to an embodiment of the present subject matter. In said embodiment, the
emergency brake release system (100) operates in the second mode of operation. Referring to
Figure 2a, the second mode of operation is defined by the reduction in the amount of the first
predetermined air pressure supplied by the primary air source (104) to about 0 bar (indicated
by dotted lines in figure 2a). As a result, the springs provided in the at least one spring brake
actuator (106) expands and sudden cramming of rear tyres/wheels of the vehicle occurs.
Referring to Figure 2b, in the second operation mode the auxiliary source provides
air at a second predetermined air pressure to release the jammed brakes. As such, the double
check valve (101) couples the auxiliary air source (105) to the at least one spring brake
actuator (106). Subsequent to the coupling, the auxiliary air source (105) provides the second
predetermined air pressure to the at least one spring brake actuator (106) thereby contracting
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the springs and disengaging the emergency brakes. In an implementation, the second
predetermined air pressure is a minimum of 4.7 bar.
The air provided at the second predetermined air pressure by the auxiliary air source
(105) feeds through the non-return valve (102) (indicated by solid line in figure 2b) and goes
to both, the second input port (108) of the double check valve (101) and the second input port
(113) of the relay valve (103). The air at the second predetermined air pressure passes from
the second input port (108) to the output port (109) of the double check valve (101) and
subsequently, feeds the at least one spring brake actuator (106). Thus, the air to disengage or
again contract the springs in the at least one spring brake actuator (106) is provided by the
auxiliary air source (105) at the second predetermined amount of air pressure.
As mentioned above, the air at the second predetermined air pressure is also fed to the
second input port (113) of the relay valve (103). As per the functionality of the relay valve
(103), the air at the second predetermined air pressure will not vent out through the venting
port (114) and thus, the air pressure is always maintained in the second input port (113) of the
relay valve (103).
Figure 3 illustrates the exemplary emergency brake release system (100), according
to an embodiment of the present subject matter. In said embodiment, the emergency brake
release system (100) operates in a third mode of operation. The third mode of operation is
defined by at least partial restoration (indicated by the solid lines in figure 3) in an amount of
the first predetermined air pressure supplied by the primary air source (104). The partial
restoration in the amount of the first predetermined air pressure may happen, for example,
after the vehicle engine maintenance.
In said embodiment, the primary air source (104) again builds up the first
predetermined air pressure and supplies the air at the first predetermined air pressure to the
first input port (107) of the double check valve (101) and the first input port (112) of the relay
valve (103). In an example, the first predetermined air pressure provided to the first input port
(107) of the double check valve (101) and the first input port (112) of the relay valve (103) is
8 bar.
In an example, at the same instant, a lower air pressure of 4.7 bar as per any one of the
previous embodiments is being fed from the output port (111) of the non-return valve (102)
to both the second input port (108) of the double check valve (101) and the second input port
(113) of the relay valve (103). In such a case, the double check valve (101) senses higher
pressure (8bar) at the first input port (107) and thus, provides the predetermined air pressure
provided by the primary air source (104) as output to the at least one spring brake actuator
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(106) through the output port (109). Thus, the emergency brake release system (100) again
operates in the first mode, as described previously with reference to Figure 1.
Continuing with the present embodiment of Figure 3, as per the functionality of the
relay valve (103), the air pressure at the first input port (112) of the relay valve (103) will act
as a control signal. Accordingly, the relay valve (103) at least vents the air between the
second input port (108) of the double check valve (101) and the output port (111) of the nonreturn
valve (102) through the venting port (114). Furthermore, the air pressure (4.7bar) from
the auxiliary air source (105) is also vented out by the relay valve (103). Thus, the original
mode of operation (or the first mode of operation) of the vehicle is restored and emergency
brake release system (100) operates in a manner as described above with reference to the
Figure 1.
Embodiments of the invention have been described in detail for purposes of clarity
and understanding. However, it will be appreciated that certain changes and modifications
may be practiced within the scope of the appended claims. Thus, although the invention is
described with reference to specific embodiments and figures thereof, the embodiments and
figures are merely illustrative, and not limiting of the invention. Rather, the scope of the
invention is to be determined solely by the appended claims.

We Claim:
1. An emergency brake release system (100) for a commercial vehicle comprising:
a double check valve (101) defining a first input port (107), a second input port (108)
and an output port (109), the first input port (107) being coupleable to a primary air
source (104) and the output port (109) being coupleable to at least one spring brake
actuator (106);
a non-return valve (102) defining an input port (110) and an output port (111), the
output port (111) of the non-return valve (102) being connected to the second input
port (108) of the double check valve (101) and the input port (110) of the non-return
valve (102) being coupleable to an auxiliary air source (Tyre) (105); and
a relay valve (103) connected between the output port (111) of the non-return valve
(102) and the second input port (108) of the double check valve (101);
such that:
in a first mode of operation defined by the primary air source (104) supplying air at a
first predetermined amount of air pressure to the at least one spring brake actuator
(106), the double check valve (101) couples the primary air source (104) to the at
least one spring brake actuator (106);
in a second mode of operation defined by a reduction in an amount of air pressure
supplied by the primary air source (104) to about 0 bar, the double check valve (101)
couples the auxiliary air source (105) to the at least one spring brake actuator (106)
and the auxiliary air source (105) supplies air at a second predetermined air pressure
to the at least one spring brake actuator (106); and
in a third mode of operation defined by at least a partial restoration in an amount of
air pressure supplied by the primary air source (104), the relay valve (103) vents at
least the air between the second input port (108) of the double check valve (101) and
the output port (111) of the non-return valve (102); and the double check valve (101)
couples the primary air source (104) to the at least one spring brake actuator (106).
2. The emergency brake release system (100) as claimed in claim 1, wherein the relay
valve (103) defines a first input port (112), a second input port (113) and a venting
port (114), the first input port (112) being coupled to the primary air source (104), the
second input port (113) being connected between the output port (111) of the nonreturn
valve (102) and the second input port (103) of the double check valve (101).
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3. The emergency brake release system (100) as claimed in claim 1, wherein the first
predetermined amount of air pressure is a minimum of 4.7 bar.
4. The emergency brake release system (100) as claimed in claim 1, wherein the second
predetermined amount of air pressure is a minimum of 4.7 bar.
5. The emergency brake release system (100) as claimed in claim 1, wherein the double
check valve (101) is a high pressure valve.
6. The emergency brake release system (100) as claimed in claim 1, wherein the primary
air source (104) is a hand control valve.
7. The emergency brake release system (100) as claimed in claim 1, wherein the
auxiliary air source (105) is at least one tyre of the commercial vehicle.