Title of Invention

INTEGRATED NON RETURN VALVE AND VACUUM LEAK SENSOR FOR AUTOMOTIVE APPLICATION

Abstract

Integrated Non Return Valve and Vacuum Leak Sensor for Autonrative Application The device relates to an integrated Non Return Valve and Vacuunn Leak Sensor for automotive brake application. It has two main components a Non Return Valve assembly and a Vacuum Leak Sensor assembly wherein Non Return Valve consist of a housing and a flap valve which does not allow air inside the booster thereby ensuring sufficiency of vacuum for assistance during brake application. A Vacuum Leak Sensor assembly having a base, an *0' ring, a spring, a spring guide and a flexible disc with contact button. The said flexible disc is capable of being pushed up by the spring such that when there is a vacuum leak in the booster the contact button presses against the terminals and establish contact. When there is no vacuum leak the flexible disc is pulled down due to presence of vacuum ensuring no contact between the two terminals.

Full Text

Integrated Non Return Valve and Vacuum Leak Sensor for Automotive Application Field of Invention This invention in general relates to automobile industry. More particularly this invention relates to integrated Non-Return Valve and Vacuum Leak Sensor for automobile brake application. Prior Art Disclosure A Non Retum Valve is an unit, which allows flow of fluid only in one direction. To ensure the presence of vacuum, a Non Retum Valve is generally fixed in a booster unit. This prevents air from entering inside the booster. A Vacuum Leak Sensor is an unit, which senses a drop in vacuum level. During a vacuum leak in the booster unit, to provide a warning indication to the driver, a Vacuum Leak Sensor is used. Vacuum Leak Sensor as known in the art and which is available today, as a separate unit, is connected either in the line between the vacuum source and the booster assembly or in the booster assembly itself. The instant invention integrates the Vacuum Leak-Sensing feature in the Non-Retum Valve assembly itself. It is well known in the art that vacuum booster assembly is an unit designed to provide power assistance to the effort applied by the driver on the brake pedal. The booster assembly provides assistance by differential pressure concept. Vacuum created in the engine inlet manifold (in case of petrol engine) or vacuum pump (in case of diesel engine) is sent to the rear chamber and front chamber. A mbber diaphragm and a diaphragm plate separate these two chambers. There are various parts on either side of the diaphragm, which are not explained here in detail, since they are not directly related to the invention. Vacuum is applied to both sides of the diaphragm through the Non Return Valve. During a brake application, atmospheric air is admitted to collapse the vacuum on the rear chamber, thereby a differential pressure is created between the chambers and thus power assistance is obtained. Should a drop occur in the vacuum level in the front chamber, or in the Non Return Valve or in the line connecting the booster assembly and the vacuum source, the power assistance will drop down. Hence a Vacuum Leak Sensor is required to indicate that there is a drop in vacuum. The device according to the invention will signal the driver about the deficiency. Accordingly what is needed in the art is an improvement that overcomes the above mentioned deficiency of the prior art. It is to be noted that the prior art description gives in detail information of the technology, method or process and device known in the art. It explains the deficiency in the related art and the object of the invention. SUMMARY OF INVENTION The inventors have made great effort to provide a device which meet the requirement of the industry and overcome the problem associated in the prior art by integration and value addition. To achieve the object according to first aspect and feature of the present invention there is provided an integrated device to improve efficiency. According to second aspect and feature of the invention in addition to the first feature the invention comprises a device, which is unique, mgged, efficient and economical. At the outset of the description which follows it is to be understood that ensuing description only illustrate a particular form of this invention. However, such particular fonri is only an exemplary embodiment without intending to imply any limitation on the scope of this invention. Accordingly, the description is to be understood as an exemplary embodiment and reading of the invention is not intended to be taken restrictively. The foregoing description is outlined rather broadly preferred and alternative feature of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that fomn the subject of claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiment as a basis for designing and modifying other structures for canrying out the same purposes of the present invention. Those skilled in the art should realize such equivalent conception do not depart from the spirit and scope of the invention in its broadest form. As it is described eariier that the primary object of invention is to invent a device which integrate the feature of Vacuum Leak Sensing in the Non-Retum Valve assembly itself. It is a Value Addition in terms of integration of existing or conventional device namely the Non Retum Valve. It is another object of invention at ease of manufacture and assembly. The invented Non Retum Valve assembly has to be replaced with this integrated unit consisting of Non Retum Valve and Vacuum Leak Sensor in order to realise the objects of the invention. Further objects of the invention will be clear from the ensuing description. The above and other objects, features and disadvantages will be clear fronn the following description of prefen^ed embodiment taken in conjunction with accompanying drawings. 1. An Integrated Non Retum Valve and Vacuum Leak Sensor for Automotive Brake Applications. The said device comprises of two main components a Non Retum Valve assembly and a Vacuum Leak Sensor assembly, wherein Non Retum Valve essentially consist of a housing and a flap valve which do not allow air inside the booster thereby ensuring sufficiency of vacuum for assistant during brake application and a vacuum leak sensor assembly having a base, an 'O' ring, a spring, a spring guide, a flexible disc with contact button said flexible disc capable of being pushed up by the spring such that when there is a vacuum leak in the booster the contact button presses against the terminals and establishes a contact and when there is no vacuum leak, the flexible disc is pulled down due to presence of vacuum ensuring no contact between the two terminals. Now the invention will be described in detail with reference to the drawings, which accompany the description. Fig. (1) shows in elevation the Booster Assembly with existing Non Retum Valve, Fig. (2) shows in elevation how the invented device is fitted in the Booster Assembly (utilising) the same porting for Non Retum Valve and Fig. (3) shows in elevation the component details of the invented device. BRIEF DESCRIPTION OF DRAWINGS The accompanying drawings are intended to provide further understanding of invention and are incorporated in and constitute a part of invention. The drawings Illustrate an emt)odiment of invention and together with the description illustrate principle of invention. i The drawings should not be taken as implying any necessary limitation on the essential scope of invention. The drawings are given by way of non-limiting example to explain the nature of the invention. For a more conriplete understanding of the instant invention reference is now made to the following description taken in conjunction with accompanying drawings. The various feature of novelty, which characterise the invention are pointed out specifically in the claims which form a part of description. For a better understanding of the invention, its operating advantage, specific objects obtained by its use, reference should be made to the drawings and descriptive matter is which there are illustrated and described preferred embodiments of invention. Refer now to drawings, where like numerals designate identical or corresponding parts throughout the referred views. Fig.1 of the drawing shows in elevation and partial cut section, parts of the conventional booster assembly. Fig.2 of the drawings shows in elevation and partial cut section, the replaced Non Return Valve assembly with the said device. Fig.3 of the drawings shows in elevation and partial cut section, various components contained in the invented device. DETAILED DESCRIPTiON OF AN EMBODIMENT OF INVENTION The device consists of two major components:- 1. A Non Return Valve (NRV) Assembly Non Return Valve consists of a housing (1) and a flap valve (2) as shown in Fig.3. The vacuum flow direction is shown in the Fig. 3 The flap valve (2) prevents air from entering inside the booster, thereby ensuring the existence of vacuum for assistance during brake application. The vacuum is collapsed during brake application to effectively assist / boost the driver's input brake pedal force. 2. A Vacuum Leak Sensor (VLS) Assembly Vacuum Leak Sensor consists of a Base (3), an 0-Ring (4), a flexible disc (5) with contact a button (6). a spring (7). a spring guide (8), two terminals (9), and an outer cover (10). When vacuum is present in the booster, the flexible disc (5) is pulled down due to the presence of the vacuum and hence there is no contact between the two terminals (9). During vacuum leak in the front chamber (12) - (Shown in Fig.1), the flexible disc (5) is pushed up due to the spring (7) and the contact button (6) comes in contact with both the terminals (9) and thus continuity is established between the two terminals (9), thereby giving an electrical indication. The indication can be visual or audible based on customer requirement. The booster assembly, shown in Fig.1, is an unit designed to provide power assistance to the effort applied by the driver on the brake pedal. The booster assembly provides assistance by differential pressure concept. Vacuum created in the engine inlet manifold (in case of petrol engine) or vacuum pump (in case of diesel engine) is sent to the rear chamber (11) and front chamber (12). A rubber diaphragm (13) and a diaphragm plate (14) separate these two chambers. There are various parts on either side of the diaphragm, which are not explained here in detail, since they are not directly related to the invention. Vacuum is applied to both sides of the diaphragm through the Non Return Valve (15). During a brake application, atmospheric air is admitted to collapse the vacuum on the rear chamber (11), differential pressure is created between both the chambers (11 & 12) and thus power assistance is obtained. Should a drop occur in the vacuum level in the front chamber (12). or in the Non Retum Valve or in the line connecting the booster assembly and the vacuum source or in the source itself, the power assistance will drop down. Hence a Vacuum Leak Sensor is required to indicate that there is a drop in vacuum. When the brake is applied, the vacuum maintained in the rear chamber (11), Is collapsed to create the differential pressure. For the booster assembly to effectively function and provide power assistance during the braking cycle, presence of required vacuum is very important. The Non Retum Valve is either fixed in the booster assembly or in the line between vacuum source and the booster assembly and maintains the vacuum level in the chambers. This prevents air from entering inside the booster assembly. To provide a warning indication to the driver, during a vacuum leak in the booster, a Vacuum Leak Sensor feature is integrated with the Non Retum Valve. The booster assembly with the integrated Non Return Valve and Vacuum Leak Sensor (16) device is shown in Fig.2. The objective of the invented device is to provide a safe braking system using a vacuum assisted booster and additionally signals the leakage of vacuum to the driver. The said device, shown in Fig.3, according to the invention is a Non-Return Valve integrated with the features of a Vacuum Leak Sensor for a Vacuum assisted booster assembly. A flap valve (2) assembled in the housing (1), ensures that vacuum is always retained in the booster assembly which is used during the brake application. Though it is not confined to a particular location within the housing, it is generally positioned below the Vacuum Leak Sensor. The flap valve (2) does not allow air at atmospheric pressure or more to enter into the booster assembly. In case there is a leak, it has to be indicated to the driver, so that the driver can take care of pedal load during further brake applications. This indication is done by the Vacuum Leak Sensor assembly, which consists of a base (3), an 0-Ring (4), a flexible disc (5) with a contact button (6), a spring (7), a spring guide (8), two terminals (9), and an outer cover (10). When vacuum is present in the booster, the flexible disc (5) is pulled down due to the presence of the vacuum and hence there is no contact between the two terminals (9). If there is a vacuum leak, the flexible disc (5) is pushed up due to the spring (7) and the contact button (6) presses against both the terminals (9) and thus continuity is established between the two terminals (9), thereby giving an electrical indication. Any type of output can be connected to the terminals (9) for leak indication - Either Visual or audible. The Vacuum Leak Sensor spring (7) is designed to offer a load to the flexible disc (5) to attain contact between the two terminals (9), till the cut-off vacuum level is reached. (Below which, is considered as leak or collapse of vacuum). The fitted load of the spring (7) can be modified suitably to have indication at any desired Vacuum level. The critical components in this assembly are the flap valve, flexible disc with contact button and the spring. If the flap valve fails, there will be a leak in the vacuum level. If the deflection of the flexible disc varies or the spring deflection varies, then the vacuum level at which the driver gets the waming will vary. ADVANTAGES OF THE INVENTION This invention is primarily intended as a safety measure for the driver to indicate the leakage of vacuum, which will enable the driver to take appropriate action. The driver will have the foreknowledge that he has to apply more pedal load to get the required pressure. Further the vacuum leak indication will demand the service of the required parts. The invention has been explained in relation to specific embodiment. It is inferred that the foregoing description is only illustrative of the present invention and it is not intended that the invention be limited or restrictive thereto. Many other specific embodiments of the present invention will be apparent to one skilled in the art from the foregoing disclosure. All substitution, alterations and modification of the present invention, which come within the scope of the following claims are to which the present invention is readily susceptible without departing from the spirit of the invention. The scope of the invention should therefore be determined not with reference to the above description but should be determined with reference to appended claims along with full scope of equivalents to which such claims are entitled. We claim : 1. an Integrated Non Return Valve and Vacuum Leak Sensor for Automotive Brake Applications. The said device comprises of two main components a Non Return Valve assembly and a Vacuum Leak Sensor assembly, wherein Non Return Valve essentially consist of a housing and a flap valve which do not allow air inside the booster thereby ensuring sufficiency of vacuum for assistance during brake application and a vacuum leak sensor assembly having a base, an '0' ring, a spring, a spring guide, a flexible disc with contact button said flexible disc capable of being pushed up by the spring such that when there is a vacuum leak in the booster the contact button presses against the terminals and establishes a contact and when there is no vacuum leak, the flexible disc is pulled down due to presence of vacuum ensuring no contact between the two terminals. 2. a device as claimed in claim 1 wherein Non Return Valve assembly consist of a housing, a flap valve which prevent air from entering inside the booster ensuring the sufficient vacuum for assistance during brake application and the said vacuum being collapsed during brake application to effectively assist / boost the driver's input brake pedal force. 3. the device as claimed in claim 1 wherein Vacuum Leak Sensor assembly consist of a base, an '0' ring, a spring, a spring guide, flexible disc with contact button, two terminals and an outer cover such that when sufficient vacuum being present there is no contact between two terminals and in the event of vacuum leak in the front chamber the flexible disc is pushed up by the spring and contact button comes into contact with both the terminals leading to vacuum leak indication. 4. the device as claimed in claim 1 wherein vacuum indication can be either visual or audible based on customer requirement. 5. the device as described in the description and as illustrated by way of drawings.

Documents:

992-che-2003-abstract.pdf

992-che-2003-claims duplicate.pdf

992-che-2003-claims original.pdf

992-che-2003-correspondnece-others.pdf

992-che-2003-correspondnece-po.pdf

992-che-2003-description complete duplicate.pdf

992-che-2003-description complete original.pdf

992-che-2003-drawings.pdf

992-che-2003-form 1.pdf

992-che-2003-form 19.pdf