FIELD OF INVENTION
This invention relates to a novel muffler for reducing noise of a vehicle.
PRIOR ART
Exhaust system is provided to reduce overall noise of an engine of vehicle,
wherein mufflers are knov^^n to have been provided for reducing the noise.
Currently, two types of muffler is used, which is either absorptive type where
dampener material is used to dempen the noise or reflective type where noise is
nullified by means of wave destructive interference.
Functionally reflective type muffler is more advantageous over absorptive type.
Further, it is more durable and results in better performance of engine.
Said reflective muffler comprising of a plurality of resonance chambers
corresponding to various frequency to reduce noise. Each chamber is provided
for a range of frequencies. However, these chambers are fixed, which can't be
adjusted so as to cater various frequencies of engine.
Hence, the present invention has been proposed.
Now, reference may be made to US 5921081:- This invention relates to a motor
vehicle muffler mounted with a plurality of baffles, in which the muffler
comprising a variable control unit such that at least one baffle in the muffler is
moved to vary volumes of chambers according to a depression of an accelerator
pedal to obtain an optimum noise attenuation effect and to increase exhaust
efficiency.
In the above Patent, a solenoid valve is attached to an accelerator pedal for
actuation of the muffler. However, it is complicated and expensive.
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OBJECTS OF THE INVENTION
The primary object of the present invention is to provide a novel muffler for
reducing noise of a vehicle which overcomes disadvantages associated with the
prior art.
Yet another object of the present invention is to provide a novel muffler for
reducing noise of a vehicle which is simple in construction and reliable.
SUMMARY OF THE INVENTION
This invention provides a novel muffler for reducing noise of a vehicle
comprising of atleast one baffle plate provided between end plates, which is
movable towards or away from the end plates by means of exhaust gases. A
resilient material is provided between the baffle plate and end plate to keep the
baffle plate in suitable position for working in engine idling.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from
the ensuing description when read in conjunction with the accompanying
drawings and wherein:
Fig. 1 shows: front view of muffler according to one embodiment of present
invention. '
Fig. lA shows: perspective view of muffler of fig. 1 ,
Fig. 2 shows: front view of muffler according to another embodiment of present t
invention.
Fig. 2A sho\vs: perspective view of muffler of fig. 2
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DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE
ACCOMPANYING DRAWINGS;-
The present invention discloses a novel muffler for reducing noise of a vehicle.
Now, reference may be made to fig. 1 and lA, wherein said muffler comprising
of a baffle plate (1) provided between end plates (2 and 3). The baffle plate is
movable towards or away from the end plates by means of exhaust gases
supplied through inlet tube (I). Further, an outlet tube (O) is provided for
exhaust of gas. There is provision of a resilient material such as spring (4 and
5) between the end plate (2) and said baffle plate (1). The spring keeps the
baffle in suitable position for working in engine idling.
The baffle plate is pushed towards the chamber having less volume of gas and
by the chamber having more volume.
The inlet tube (1) and outlet tube (O) are provided with a plurality of
perforations for passage of gas. Said perforations are having different
diameters, which is determined relying on the design.
Said baffle plate can also be provided with a plurality of perforations, which is
based on the exhaust mass flow rate.
The muffler is made of material such as stainless steel (SS) without restricting
scope of the invention to the same. Other materials readily apparent to person
skilled in the art are understood to be within scope of the invention.
The material of said muffler should be able to withstand temperature of gas
and preferably corrosion resistant.
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It can be manufactured by press forming, wherein each component of said
muffler is made by press forming. This is followed by assembling of the
components to obtain the muffler.
Increase in engine speed leads to increase in pressure of gas, which moves the
baffle plate towards the end plate. This creates a different volume for different
frequency of engine noise.
Relying on engine characteristics i.e. engine displacement and gas force in
chamber during engine RPM variations, muffle volume and spring stiffness are
determined.
The aforesaid arrangement can also be provided where more than two chamber
is provided.
Now, reference may be made to fig. 2 and 2A, in which three chambers are
provided with two baffle plates (1) between the end plates (2 and 3). The
resilient material (4 85 5) is provided between each end plate (2 and 3) and each
baffle plate (1) as shown in fig.
Said baffle plates are having a number of perforations on their surface for flow
of gas from one chamber to adjacent chamber.
Further, a guide (G) is provided with each baffle plate for aligned movement of
the baffle plate due to gas pressure. The shape of the muffler can be
circular/elliptical.
It is to be noted that the present invention is susceptible to modifications,
adaptations and changes by those skilled in the art. Such variant embodiments
employing the concepts and features of this invention are intended to be within
the scope of the present invention, which is further set forth under the
following claims:-

WE CLAIM;
1. A novel muffler for reducing noise of a vehicle comprising of atleast one
baffle plate provided between end plates, which is movable towards or
away from the end plates by means of exhaust gases, wherein a resilient
material is provided between the baffle plate and end plate to keep the
baffle in suitable position for working in engine idling.
2. A novel muffler as claimed in claim 1, wherein the resilient material is
such as spring.
3. A novel muffler as claimed in claim 1 or 2, wherein the baffle plate may
be provided with a plurality of perforations for flow of gas from one
chamber to adjacent chamber.
4. A novel muffler as claimed in any of the preceding claims, wherein guide
may be provided with the baffle plate for its movement in an alignment.
5. A novel muffler as claimed in any of the preceding claims, wherein a
baffle plate is placed between two end plates and a spring connects one
end plate with said baffle plate.
6. A novel muffler as claimed in any of the preceding claims, wherein two
baffle plates are located between end plates, in which a spring is
provided to connect one baffle plate with one end plate.
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— 7. A novel muffler as claimed in any of the preceding claims, wherein
increase in engine speed leads to increase in pressure of gas, which
moves the baffle plate towards the end plate thereby creating a different
volume for different frequency of engine noise.
8. A novel muffler as claimed in any of the preceding claims, wherein
muffler volume and spring stiffness are determined relying on engine
characteristics of displacement of engine and pressure of gas in chamber
during engine RPM variations.
9. A novel muffler as claimed in any of the preceding claims, wherein the
muffle is applicable to any number of chambers.
10. A novel muffler as claimed in any of the preceding claims, wherein
the muffler accommodates inlet tube for supply of exhaust gas and outlet
tube for exhaust of gas, in which a plurality of perforations of different
diameter are provided on the surface of said inlet and outlet tube.