[0001] The present invention relates generally to vehicles and particularly, but not exclusively, to a suction air filter of a three wheeled vehicle.
BACKGROUND
[0002] A three-wheeled vehicle conventionally has an engine disposed towards the rear side, behind the passenger cabin. The engine includes an exhaust port through which exhaust gases are expelled. The exhaust gases, often include unburnt hydrocarbon which, if left untreated cause severe pollution and result in a low overall efficiency of said engine. The unburnt hydrocarbons in the exhaust gases are burnt at a catalytic converter placed, usually in the muffler. Burning of the unburnt hydrocarbons requires input of oxygen-rich air which is supplied by a secondary air injection system. The secondary air injection system is typically configured to draw fresh oxygen in order not to draw gases from the air intake of primary air injection system to the engine.
[0003] The secondary air injection system, thus, ensures a separate oxygen-rich air flow to the exhaust port of the engine. The air intake by the secondary air injection system is generally filtered to remove dirt, dust and water. However, the rear wheels of the three-wheeled vehicle tend to throw up a copious amount of contaminants tangentially, when the three-wheeled vehicle is in motion which have potential to enter the secondary air intake system. Owing to this, the filter of the secondary air injection system can result in getting clogged due to an excessive input of contaminants such as dirt, dust and water, along with the oxygen-rich air. Said clogging of the filter of the secondary air injection system can necessitate frequent replacement of said filter which is an expensive and laborious process.
BRIEF DESCRIPTION OF DRAWINGS
[0004] The detailed description of the present subject matter is described with reference to the accompanying figures. Same numbers are used throughout the drawings to reference like features and components.

[0005] Fig. 1 illustrates a right side view of an exemplary three-wheeled vehicle, in accordance with an embodiment of the present subject matter.
[0006] Fig. 2 illustrates a rear view of the exemplary three-wheeled vehicle, in accordance with an embodiment of the present subject matter.
(0007] Fig. 3 illustrates a perspective view of the secondary air injection system of the'exemplary three-wheeled vehicle, in accordance with an embodiment of the present subject matter.
[0008] Fig. 4 illustrates a side view of the secondary air injection system of the exemplary three-wheeled vehicle, in accordance with an embodiment of the present subject matter.
DETAILED DESCRIPTION
[0009] Conventionally, a three-wheeled vehicle that is powered by an engine, generally expels exhaust gases that are fuel-rich or has a considerable amount of unburnt hydrocarbons still left. Expulsion of the exhaust gases from the engine without treating the unburnt hydrocarbons results in air pollution and also results in a low overall efficiency of the engine.
[0010] Burning of the fuel-rich exhaust gases to supplement the energy produced by the engine serves a dual purpose of the exhaust gases being formed mainly of carbon dioxide and also to augment the amount of energy produced by the engine, thereby, increasing the overall efficiency of the engine.
[0011] Combustion of the unburnt hydrocarbons present in the exhaust requires input of oxygen-rich air which may be drawn either from a primary air injection system which supplies air to the engine or it may be drawn from a secondary air injection system that is dedicated to supplying oxygen-rich air to an exhaust port of the engine for the combustion of unburnt hydrocarbons in the exhaust. Having a secondary air injection system separate from the primary air injection system has the advantage of preventing fluctuations and causing of pulses in the engine air intake every time a certain quantum of air is diverted to the catalytic converter

which facilitates combustion of unburnt fuel in the exhaust gases exiting the engine exhaust port.
[0012] While the air inlet of the primary air injection system is secured upward, sideways and outside an engine compartment housing the engine and its ancillary components, air inlet of the secondary air injection system is exposed to contaminants such as dirt, dust and water thrown up tangential ly by a rear wheel of the three-wheeled vehicle, especially when said three-wheeled vehicle is in motion.
[0013] The secondary air injection system is conventionally provided with an air filter to prevent entry of atmospheric contaminants into the exhaust port and further into exhaust channels of the engine. Such contaminants affect the functioning and lifetime of the catalytic converter. Therefore, the filter screens out the atmospheric contaminants present in the air taken in by the secondary air injection system through the air inlet of the secondary air injection system. Disposing the inlet of the secondary air injection away from the engine compartment which may also house the powertrain can be uneconomical, involve complex routing oflhe intake pipes & hoses as well as lead to poor durability / life of the hoses and entire secondary air injection system as such. Thus, there is a need to have the inlet within the said rear compartment at the same time address the issue of undesirable entry of contaminants affecting functioning of the filter & the powertrain as a whole.
[0014] The filter, however, tends to get clogged if the air that is taken in by the air inlet of the secondary air injection system also contains contaminants thrown up by the rear wheel of the three-wheeled vehicle. The air filter, once clogged, must be either replaced or cleaned. Such frequent replacement or cleaning of the air filter of the secondary air injection system is a costly process! Also, it increases the number of times the three-wheeled vehicle is required to be serviced, which is expensive'as well as time consuming. Therefore, a secondary air injection system that provides contaminant free air for combustion of unburnt hydrocarbons in exhaust gases, while preventing excessive clogging of the air filter of the secondary air injection system is desirable in the art.

[0015] The present invention discloses a secondary air injection system comprising an air inlet and an air filter, wherein the air inlet is located in an enclosure. The enclosure allows passage of air to the secondary air injection system through the air inlet, however, the enclosure prevents contaminants from ingressing through said air inlet of the secondary air injection system.
[0016] In one embodiment, the air filter and air inlet of the secondary air injection system are connected through a hose. A hose ensures leak-proof transmission of air from the air inlet to the air filter. As per one embodiment, the air inlet of the secondary air injection system is located in an enclosure, said enclosure being mounted on a. wall of an engine compartment which houses the engine and all ancillary components. The mounting of the enclosure on a wall of the engine compartment has the advantage of firmly securing the hose connecting the air filter and the air inlet, thereby preventing damage of said hose due to excessive vibrations that it would otherwise be subject to. Moreover, disposing the enclosure on the wall of the engine "compartment aids in effective space"managementr~makes it economical, reduced length of hoses and lower complexity of design.
[0017] In one embodiment, the wall on which the enclosure of the air inlet is placed is a vertical wall. Mounting the enclosure on the vertical wall allows the inlet to be placed at an elevated position, away from any contaminants that are thrown up by one or both of the rear wheels of the three-wheeled vehicle. In said elevated position, ingress of contaminants from other sources into the secondary air injection system is also minimized.
(0018] As per one embodiment, the enclosure of the air inlet of the secondary air injection system is a TCI (Transistorized Capacitor Ignition system) case which ■serves a dual function of housing TCI (Transistorized Capacitor Ignition system) units as well as have housing the enclosure of the air inlet of the secondary air injection system. The TCI (Transistorized Capacitor Ignition system) case has at least one aperture for drawing in air and at least one other aperture through which the housing connecting the air inlet and the air filter of the secondary air injection system.

|0019] In one embodiment, the secondary air injection system has an air inlet that is located in an enclosure, thereby, restricting entry of contaminants such as dirt, dust or water, especially thrown up by one or more of the rear wheels. Thus, the secondary air injection system with the air inlet located in an enclosure prevents unnecessary clogging up of the air filter due to unimpeded ingress of contaminants along with air, thereby dispensing with the need to frequently replace or clean the air filter. Thus, the present subject matter provides a solution to the problem of unimpeded inflow of contaminants through the air inlet into the secondary air injection system, which is required to be filtered by the air filter, thereby drastically increasing the rate at which it is clogged and hence, needs to be replaced or cleaned.
[0020] Advantageously, the present invention describes a secondary air injection system in which the air inlet is located in an enclosure that is mounted on a wall of the engine compartment for effective space management as well as to preserve longevity of the hose connecting the air inlet to the air filter. Further, the present
JrLvention_discloses_mounting.of.the enclosure-of-the-air-inlet-on-to-a-vertieal-wall —
to ensure that the air inlet is in an elevated position, so as to inhibit entry of contaminants such as dust, dirt and water, usually thrown up by one or more of the rear wheels when the thee-wheeled vehicle is in motion or the contaminants usually prevalent in considerable amount at a lower level or height.
[0021] As per one embodiment, the present invention additionally has the advantage of enabling the TCI (Transistorized Capacitor Ignition system) case to have a dual function of acting as an enclosure for the air inlet of the secondary air injection system, apart from its regular function of housing TCI (Transistorized Capacitor Ignition system) units. This results in an economic advantage as well as conserves space in the engine compartment of the three-wheeled vehicle. Therefore, the present invention addresses the drawbacks prevalent in the state of the art. Apart from the advantages already mentioned, the described invention has several advantages over conventional arrangements prevalent in state of the art.
[0022] Various other features and advantages of the invention are described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or

structurally similar elements. The drawing in .which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number. With reference to the accompanying drawings, wherein the same reference numerals will be used to identify the same or similar elements throughout the several views. It should be noted that the drawings should be viewed in the direction of orientation of the reference numerals.
[0023] Fig. 1 illustrates a right side view of an exemplary three-wheeled vehicle (100) without the soft top or roof structure, in accordance with an embodiment of the present subject matter. As per one embodiment, the three-wheeled vehicle has a front cowl (106) supporting a windscreen (103). As per one embodiment, the lower portion of the front cowl (106) is connected to a front wheel (108) with a wheel cover (107) disposed in between. A pair of left and right front light assembly (105) disposed on the front cowl (106) of the three-wheeled vehicle (100). A handlebar assembly (104) is present behind the front cowl (106) which is used to operate the vehicle (100). As per one embodiment of the present invention, a floor panel (112) is extending from the bottom portion of the front cowl (106) to the rearward direction of the vehicle (100), supported by a vehicle frame assembly (not shown). In one embodiment, the vehicle (100) has a driver's seat assembly (109) in a front portion of the vehicle (100) and a passenger compartment having at least one passenger seat assembly (113) in a rear portion of the vehicle (100). Further, as per one embodiment, said pair of rear wheels (114) are connected to a swing arm through one or more rear suspension(s). The rear suspension includes a shock absorber and a suspension spring unit (115) mounted to the vehicle frame assembly. The engine (shown in figure 2) and all the ancillary components are disposed behind the passenger seat assembly (113) in an engine compartment (110).
[0024] Fig. 2 illustrates an isometric view of the exemplary three-wheeled vehicle (100), in accordance with an embodiment of the present subject matter, showing the components of the engine compartment (110). The engine compartment (110) has the secondary air injection system (300) shown in Fig.3) connected to an engine (250). The secondary air injection system (shown in Fig.3) includes an enclosure (201), an inlet aperture (202), an inlet hose (204), an air filter

(205), a filter hose (206), a valve (207), a valve hose (208), an exhaust port (210) and a vacuum hose (209). The enclosure (201) includes the inlet aperture (202) through which air enters the enclosure and thereon to the air inlet of the secondary air injection system (as shown in figure 3). An inlet hose (204) connects the air inlet in the enclosure (201) and the air filter (205). The filter hose (206) connects the air filter (205) and the valve (207). The valve hose (208) connects the valve (207) and the exhaust port (210) of the engine (250). Suction pressure for the valve (207) is provided through the vacuum hose (209). In one embodiment, the exhaust gases flowing out of the engine (250) cause a negative pressure which draws in air from the secondary air injection system (shown in Fig.3), Air enters the enclosure (201) through the inlet aperture (202), passes through the air inlet in the enclosure (201). The air is then transmitted to the air filter (205) from the air inlet through the inlet hose (204). After being filtered in the air filter (205)", the air is transmitted to the filter hose (206). The valve (207) sucks in the air present in the filter hose (206) when a suction pressure is applied through the vacuum hose (209). The valve hose (208) transmits the air from the valve (207) to the exhaust port (210) of the engine (250).
[0025] Fig. 3 illustrates a perspective view of the secondary air injection system (300) of the exemplary three-wheeled vehicle (100), in accordance with an embodiment of the present subject matter. The secondary air injection system (300) includes the enclosure (201), the inlet aperture (202), the inlet hose (204), the air filter (205), the filter hose (206), the valve (207), the valve hose (208), the exhaust port (210) and the vacuum hose (209). As shown in the figure, the inlet hose (204) of the secondary air injection system (300) connects the air inlet to the air filter (205), the inlet hose (204) emerging out of the enclosure (201) through an air-tight opening (301), in the present embodiment. In another embodiment, the enclosure (300) is a TCI (Transistorized Capacitor Ignition system) case which has the dual function of housing TCI (Transistorized Capacitor Ignition system) units as well as housing the air inlet of the secondary air injection system (300).
[0026] Fig. 4 illustrates a side view of the engine compartment (110) of the exemplary three-wheeled vehicle (100), in accordance with an embodiment of the

present subject matter. The secondary air injection system (300) includes the enclosure (201), the inlet aperture (202), the inlet hose (204), the air filter (205), the filter hose (206), the valve (207), the valve hose (208), the exhaust port (210) and the vacuum hose (209). In the present embodiment, the enclosure (201) is mounted on a wall (401) of the engine compartment (110). In another embodiment, the wall (401) is vertically inclined. Mounting the enclosure on the wall (401) has the advantage of enabling effective space management as well as to ensure longevity of the inlet hose (204), the filter hose (206), the valve hose (208) and the vacuum hose (209).
[0027] It is to be understood that the aspects of the embodiments are not necessarily limited to the features described herein. Many modifications and variations of the present subject matter are possible in the light of above disclosure. Therefore, within the scope of claims of the present subject matter, the present disclosure may be practiced other than as specifically described.

1. A three-wheeled vehicle (100), said three-vvhcclcd vehicle comprising:
an engine (250) disposed in an engine compartment (110), said engine (250) including an exhaust port (210);
a secondary air injection system (300) adapted to inject air into the said exhaust port (210) of the engine (250), said secondary air injection system (300) includes an air inlet and an air filter (205), said air inlet being located in an enclosure (201).
2. The three-wheeled vehicle (100) as claimed in claim I wherein said
. enclosure (201) is disposed in the engine compartment (110).
3. The three-wheeled vehicle (100) as claimed in claim 1, wherein said enclosure is disposed on a wall (401) of the engine compartment (110)
4. The three-wheeled vehicle (100) as claimed in claim 1, wherein said enclosure (201) includes at least one opening (301) adapted to allow passage of an inlet hose (204), said inlet hose (204) connecting the air inlet and the air filter (205) of the secondary injection system (300).
5. The three-wheeled vehicle (100) as claimed in claim 1, wherein said enclosure (201) includes an inlet aperture (202) adapted to allow inflow of air into the enclosure (201).
6. The three-wheeled vehicle (100) according to claim 1, wherein said enclosure (201) is a case that houses the Transistorized Capacitor Ignition system.