FIELD OF THE INVENTION

The present disclosure relates to a sensor assembly and more particularly, relates to an air filter clog sensor assembly having an adjustable range of detectable vacuum pressure for an air filter.

BACKGROUND

Owing to the ever-growing pollution in the environment, air filters find their application across various industries, ranging from industrial facilities to automobiles to vacuum cleaners. As is generally known, air filters are employed to remove airborne pollutants from entering a piece of equipment which otherwise may affect the operation of the equipment, for example, by causing a malfunction or a reduction in overall efficiency. Particularly, in case of automobiles, air filters are generally used in internal combustion engines. Clogged air filters may be a direct cause of a significant decrease in the efficiency of the engine and therefore, of more consumption of fuel. It may also increase wear and tear of the engine thereby resulting in reduction of service life of the engine. Therefore, it becomes relevant to ensure timely maintenance of the air filter.

Nowadays, air filters include a sensor to detect clogging of the air filter. For example, the sensor may be configured to generate a notification indicative of the clogging reaching an unacceptable level. Therefore, the notification may be indicative of the requirement of maintenance of the air filter. The existing sensors are preconfigured to generate the notification at a predefined level of the clogging. The predefined level cannot be changed while being in operation. Therefore, a sensor configured for a specific application cannot be used for another application considering the fixed-output type arrangement.

Further, existing sensors usually include a housing and a cover mounted on the housing. However, the mounting is such that there exists a possibility of an undesired rotation of components with respect to each other. Such movement of the components may hamper an overall operation of the sensor. Moreover, the sensors are not appropriately sealed and therefore, allow infiltration of dust and other particles within the assembly leading to a potential failure. Consequently, an overall efficiency of the sensors and consequently, of the air filter is reduced. Therefore, there is a lack of reliability and robustness in the conventional sensors.

SUMMARY

This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.

In an embodiment of the present disclosure, an air filter clog sensor assembly is disclosed. The air filter clog sensor assembly includes a housing, a cover mounted on the housing forming a chamber, and a diaphragm mounted inside the housing and is adapted to move in response to a vacuum pressure in the chamber. The air filter clog sensor assembly further includes a micro-switch disposed in the cover adapted to transmit signals indicative of the vacuum pressure. The micro-switch transmits a signal when the diaphragm releases the micro-switch once a threshold value of the vacuum pressure is achieved. The air filter clog sensor assembly includes a compression spring coupled to the micro-switch to retract the diaphragm to an original state to stop the transmission of the signal. The air filter clog sensor assembly also includes an adjuster disposed in the housing, coupled to the compression spring, and adapted to be rotated to control a range of vacuum pressure to be indicated by the micro-switch by varying an initial force of the compression spring. The initial force is indicative of a force before compression of the compression spring.

To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is 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.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

Figure 1 illustrates a perspective view of an air filter clog sensor assembly, according to an embodiment of the present disclosure;
Figure 2 illustrates an exploded view of the air filter clog sensor assembly, according to an embodiment of the present disclosure;
Figure 3 illustrates a cross-sectional view of the air filter clog sensor assembly, according to an embodiment of the present disclosure;
Figure 4 illustrates a cross-sectional view of the air filter clog sensor assembly, according to another embodiment of the present disclosure; and
Figure 5 illustrates an exploded view of the air filter clog sensor assembly, according to another embodiment of the present disclosure.

Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the device, one or more components of the device 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 present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES

For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment 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. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Figure 1 illustrates a perspective view of an air filter clog sensor assembly 100, according to an embodiment of the present disclosure. The air filter clog sensor assembly 100 is hereinafter interchangeably referred to as the sensor assembly 100. The sensor assembly 100 may include a housing 102 and a cover 104 mounted on the housing 102. In an embodiment, the cover 104 is snap-fitted with the housing 102. Therefore, the cover 104 and the housing 102 are attached with each other through a snap-fit lock 106. The housing 102 and the cover 104 form a chamber.

In an embodiment, the sensor assembly 100 may be coupled with an air-filter pipe (not shown). The air-filter pipe may be understood as an inlet duct or an outlet duct of an air filter (not shown). The air filter and the air-filter pipe have a dynamic vacuum pressure based on the operation. In an embodiment, an engine having the air filter may suck the air, and the air may then pass through the air filter. When the air filter is clogged, the vacuum pressure increases. In an embodiment, the sensor assembly 100 may detect the increase in the vacuum pressure and generate a notification to be provided on an instrument cluster of a vehicle having the air filter. In an embodiment, the notification may be provided through at least one of a bulb or a Light Emitting Diode (LED) indicator. In an embodiment, the sensor assembly 100 may generate the notification and transmit the notification to an electronic control module (not shown) of the vehicle.

Figure 2 illustrates an exploded view of the sensor assembly 100, according to an embodiment of the present disclosure.

Figure 3 illustrates a cross-sectional view of the sensor assembly 100, according to an embodiment of the present disclosure.

Figure 4 illustrates a cross-sectional view of the sensor assembly 100, according to another embodiment of the present disclosure. For the sake of brevity, constructional and operational features of the sensor assembly 100 that are already disclosed in the description of Figure 1 are not disclosed in detail in the description of Figure 2, Figure 3, and Figure 4.

Referring to Figure 1, Figure 2, Figure 3, and Figure 4, the sensor assembly 100 may include, but is not limited to, the housing 102, the cover 104, a diaphragm 202 mounted inside the housing 102, a micro-switch 204 disposed in the cover 104, a compression spring 206 coupled to the micro-switch 204, and an adjuster 208 coupled to the compression spring 206.

In an embodiment, the diaphragm 202 may be fixed by a round projection in the cover 104. The diaphragm 202 may be adapted to move in response to a vacuum pressure in the chamber. In an embodiment, the diaphragm 202 may be mounted in an annular channel inside the housing 102 by using a press-fit technique. Therefore, no additional fastener is used for mounting the diaphragm 202. Further, the micro-switch 204 may be adapted to operate to transmit signals indicative of the vacuum pressure in the chamber at different time instances.

In an embodiment, the micro-switch 204 may be configured to transmit a signal when the diaphragm 202 releases the micro-switch 204. The diaphragm 202 may release the micro-switch 204 when a threshold value of the vacuum pressure is achieved in the chamber. Therefore, the threshold value of the vacuum pressure may be predefined for the sensor assembly 100. When the vacuum pressure in the chamber reaches the threshold value, the micro-switch 204 may get released and operate to transmit a signal indicative of the vacuum pressure. In an embodiment, the micro-switch 204 may operate to indicate that maintenance of the sensor assembly 100 is due.

When the diaphragm 202 is pulled away from the micro-switch 204 to generate the signals, it has to be retracted to its original state when the vacuum pressure varies. In an embodiment, the compression spring 206 may retract the diaphragm 202 to an original state and push the micro-switch 204 to stop the transmission of the signal. Therefore, the diaphragm 202 may be understood as a sensing element for the sensor assembly 100.

The adjuster 208 may be coupled to the compression spring 206 and the micro-switch 204. In an embodiment, the compression spring 206 and the micro-switch 204 may be coupled to a movable surface of the adjuster 208. In an embodiment, the adjuster 208 may include a slit-type opening in the centre. In an embodiment, the adjuster 208 may have threads on an outer periphery. While being disposed in the housing 102, the threads of the adjuster 208 may engage with corresponding threads in an annular channel inside the housing 102.

The adjuster 208 may be adapted to be rotated to control a range of vacuum pressure to be indicated by the micro-switch 204. The adjuster 208 may be adapted to move in an upward direction when the adjuster 208 is rotated in a clockwise direction. Similarly, the adjuster 208 may be adapted to move in a downward direction, when the adjuster 208 is rotated in an anti-clockwise direction. In an embodiment, the adjuster 208 may move in the upward direction or the downward direction, based on a pitch distance of the threads.

The range of vacuum pressure may be controlled as the rotation of the adjuster 208 may vary an initial force of the compression spring 206. The spring compression in the sensor assembly 100 may depend on an installed or initial height of the compression spring 206. In an embodiment, the initial force of the compression spring 206 may be indicative of a force before compression of the compression spring 206. Therefore, the range of vacuum pressure to be indicated by the micro-switch 204 varies, based on a change in the spring compression caused by the upward and downward motion of the adjuster 208.

In an embodiment, the adjuster 208 may automatically be rotated by using a specific tool. For example, the adjuster 208 may include a rectangular slot for accessing a tool, such as a screw driver flat-type. The tool may be used to rotate the adjuster 208. In another embodiment, the adjuster 208 may be manually rotated as well.

In an embodiment, the sensor assembly 100 may include a diaphragm disc 210 disposed between the diaphragm 202 and the micro-switch 204. The diaphragm disc 210 may be adapted to operate the micro-switch 204. Further, the sensor assembly 100 may include a diaphragm carrier 212 disposed between the diaphragm 202 and the compression spring 206. The diaphragm carrier 212 may be disposed to protect the diaphragm 202 from an operational tear, for example, from the compression spring 206. In an embodiment, the diaphragm carrier 212 may be formed of plastic. In an embodiment, the compression spring 206 may be coupled to the micro-switch 204 through the diaphragm disc 210 and the diaphragm carrier 212.

In an embodiment, the micro-switch 204 may include at least a pair of terminals 214. The pair of terminals 214 may include, but is not limited to, a male terminal and a female terminal. Further, the sensor assembly 100 may include a micro-switch support 216 disposed between the micro-switch 204 and the diaphragm disc 210. The micro-switch support 216 is adapted to support the micro-switch 204 in the sensor assembly 100.

In an embodiment, the sensor assembly 100 may also include a dust filter 218 and a washer 220 disposed at the bottom of the sensor assembly 100. In an embodiment, the sensor assembly 100 may include a sealant 402 at an interface between the housing 102 and the cover 104. In particular, the sealant 402 may be disposed at an annular channel of the cover 104 in which the housing 102 may engage when assembled. Once the sealant 402 is cured, the sealing between the housing 102 and the cover 104 may be formed. In an embodiment, the sealant 402 may be formed of materials that may include, but are not limited to, solid rubber. The solid rubber may include, but is not limited to, Ethylene Propylene Diene Monomer (EPDM).

In an embodiment, the sealant 402 may be used at the end of threads provided on an outer periphery of the housing 102 which may engage with the air filter of the vehicle. When the housing 102 is mounted with a specific torque, the solid rubber may form a sealing between the air filter and the sensor assembly 100.

In an embodiment, the sensor assembly 100 may be actuated at a vacuum pressure of 80 ± 4 millibars. In another embodiment, the sensor assembly 100 may be actuated at a vacuum pressure of 65 millibars. In other embodiments, the sensor assembly 100 may be actuated at any value of the vacuum pressure by making minor modification to the construction, for example, of the compression spring 206.

Figure 5 illustrates an exploded view of the sensor assembly 100, according to another embodiment of the present disclosure. In the present embodiment, the position of the adjuster 208 with respect to the housing 102 and the cover 104 is different than the embodiment as shown in Figure 2, Figure 3, and Figure 4. For the sake of brevity, constructional and operational features of the sensor assembly 100 that are already disclosed in the description of Figure 1, Figure 2, Figure 3, and Figure 4 are not disclosed in detail in the description of Figure 5.

As would be gathered, the present disclosure offers the sensor assembly 100 that is sealed and adapted to adjust the vacuum pressure to be indicated. Considering that the compression spring 206 is adjustable owing to the movement of the adjuster 208, the vacuum pressure can be adjusted within the sensor assembly 100. Due to the adjustable range of vacuum pressure, the sensor assembly 100 can be used for multiple applications having the demand for detection of a different range of vacuum pressure.

Further, the interlocking mechanism between the housing 102 and the cover 104 due to the snap-fit lock 106 may restrict any unwanted relative rotation or movement of the components of the sensor assembly 100. Furthermore, the sensor assembly 100 of the present disclosure has a completely sealed design against, water and dust infiltration.

Also, the construction of the sensor assembly 100 is such that the adjuster 208 may be accessed without opening the sensor assembly 100. The adjuster 208 is further protected and cannot be disturbed while in operation. Further, as is the case in the conventional sensors, one side of the diaphragm 202 is not used as a barrier to debris in the sensor assembly 100 of the present disclosure as the sensor assembly 100 is sealed and therefore, infiltration of debris is not possible. In the present embodiment, the diaphragm 202 does not have any protrusion and is not welded to any of the components. Furthermore, AC coil is not required for operating the diaphragm 202 of the present disclosure. Also, the diaphragm disc 210 used to operate the micro-switch 204 doesn’t require any nut as a fastener.

In addition, the sensor assembly 100 has a plastic body and doesn’t include any indicator lamp inside. The sensor assembly 100 may operate on a 12Volts system, and doesn’t require any resistor. Moreover, the sensor assembly 200 is electro-mechanical in nature and doesn’t include a rack and pinion mechanism. Further, the sensor assembly 100 doesn’t include any metal bracket for mounting, a spacer, bellows, a filter screen, a desiccant, a peripheral circuit, a membrane, and a control circuit. Therefore, the present disclosure offers the sensor assembly 100 that is light-weight, sturdy, flexible, efficient, cost-effective, sealed and has a wide range of application.

While specific language has been used to describe the present disclosure, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment.

WE CLAIM:

1. An air filter clog sensor assembly (100) comprising:
a housing (102);
a cover (104) mounted on the housing (102) forming a chamber;
a diaphragm (202) mounted inside the housing (102) and is adapted to move in response to a vacuum pressure in the chamber;
a micro-switch (204) disposed in the cover (104) adapted to transmit signals indicative of the vacuum pressure, wherein the micro-switch (204) transmits a signal when the diaphragm (202) releases the micro-switch (204) once a threshold value of the vacuum pressure is achieved;
a compression spring (206) coupled to the micro-switch (204) to retract the diaphragm (202) to an original state to stop the transmission of the signal; and
an adjuster (208) disposed in the housing (102), coupled to the compression spring (206), and adapted to be rotated to control a range of vacuum pressure to be indicated by the micro-switch (204) by varying an initial force of the compression spring (206), wherein the initial force is indicative of a force before compression of the compression spring (206).

2. The air filter clog sensor assembly (100) as claimed in claim 1, comprising a diaphragm disc (210) disposed between the diaphragm (202) and the micro-switch (204), and adapted to operate the micro-switch (204).

3. The air filter clog sensor assembly (100) as claimed in claim 1, further comprising a diaphragm carrier (212) disposed between the diaphragm (202) and the compression spring (206), wherein the diaphragm (202) carrier is disposed to protect the diaphragm (202) from operational tear.

4. The air filter clog sensor assembly (100) as claimed in claim 1, wherein the adjuster (208) is adapted to move in an upward direction and a downward direction, when rotated clockwise and anti-clockwise, respectively.

5. The air filter clog sensor assembly (100) as claimed in claim 4, wherein the range of vacuum pressure to be indicated by the micro-switch (204) varies, based on the upward and downward motion of the adjuster (208).

6. The air filter clog sensor assembly (100) as claimed in claim 1, wherein the adjuster (208) having threads is engaged in an annular channel formed inside the housing (102) having corresponding threads.

7. The air filter clog sensor assembly (100) as claimed in claim 1, wherein the diaphragm (202) is mounted in an annular channel inside the housing (102) by using a press-fit technique.

8. The air filter clog sensor assembly (100) as claimed in claim 1, wherein the cover (104) is snap-fitted with the housing (102).

9. The air filter clog sensor assembly (100) as claimed in claim 1, comprising a sealant (402) disposed at an interface of the housing (102) and the cover (104), wherein the sealant is formed at least of solid rubber.

10. The air filter clog sensor assembly (100) as claimed in claim 9, wherein the solid rubber at least includes Ethylene Propylene Diene Monomer (EPDM).