Title of Invention

SAFETY SYSTEM FOR EXCESSIVE GAS PRESSURE IN A TWO WHEELER MOTOR VEHICLE RUNNING ON LPG

Abstract

A safety system for excessive gas pressure in a two wheeler motor vehicle running on LPG, comprising a replaceable LPG cylinder rigidly accommodible in a housing provided for the vehicle, the cylinder being provided with a swivel valve and a built-in normally closed first pressure relief valve located on the cylinder body, such first pressure relief valve being preset to open whenever the gas pressure within the cylinder exceeds a first predetenn ined value, characterised by a norm ally closed second pressure relief valve incorporated in the LPG line downstream of the outlet of the said cylinder, next to the said outlet, the said second pressure relief valve being preset to open whenever the gas pressure within the cylinder exceeds a second predetenn ined value higher than the first predetermined value.

Full Text

This invention relates to a safety system for C$f£$J&6Y protection against build-up of excessive gas pressure in a replaceable LPG cylinder system for a two wheeler motor vehicle running on LPG. Use of LPG as fuel for propulsion of automobiles offers advantages of low running costs, lower emissions, longer engine life and lower maintenance costs when compared to their gasoline/diesel counterparts. LPG as fuel has also been found to be non-carcinogenic, non-lead bearing. It has further been found that leaner mixtures of LPG can be combusted and higher compression ratios can be obtained due to the higher octane number and because the fuel is in gaseous form. LPG is being commercially used in automobiles in Australia, Japan, USA, Holland, Italy, New Zealand among other countries. Efforts are being made in India, which has a huge motor vehicle population, for use of LPG in automobiles, with adequate safeguards. The LPG commercially available in India is a mixture of butane and propane with traces of other hydrocarbons. This invention proposes a safety system for excessive gas pressure in a replaceable LPG cylinder for a two wheeler motor vehicle. The cylinder is so constructed that it can be rigidly attached to a housing, when located within it so that it is securely advanced in place. According to this invention, die safety system for excessive gas pressure in a two wheeler motor vehicle running on LPG, comprises a replaceable LPG cylinder rigidly accom mod able » a housing provided for die vehicle, the cylinder being provided with a swivel valve and a built-in normally closed first pressure relief valve located on the cylinder body, such first pressure relief valve being preset to open whenever die gas pressure within the cylinder exceeds a first predetermined value, characterised by a normally closed, second pressure relief valve, incorporated in the LPG line downstream of the outlet of the said cylinder, next to the said outlet, the said second pressure relief valve being preset to open whenever the gas pressure within the cylinder exceeds a second predetermined value higher than the first predetermined value. The safety system proposed herein will now be described with reference to the accompanying drawings, the single Figure in which illustrates, by way of example, and not by way of limitation, one of various possible embodiments of this invention. The replaceable LPG cylinder C is rigidly accommodable in a housing H, provided for the vehicle. The cylinder is provided with a swivel valve S, an excess flow cum shut-off valve E. A quick disconnect coupling D is also provided. A normally closed, built-in first pressure relief valve Rl, located on the body B of the cylinder C, is preset to open whenever the gas pressure within the cylinder exceeds a first predetermined value. In this invention, a second normally closed, pressure relief valve R2 is incorporated in the LPG line L downstream of the outlet O of the said cylinder, next to the said outlet. In the embodiment illustrated, this valve is located between the swivel valve S and the excess flow cum shut-off valve E. The valve R2 is preset to open whenever the gas pressure within the cylinder C exceeds a second predetermined value, higher than the first predetermined value. The cylinder C, which is carried by the two wheeler motor vehicle, is subject to many external forces, such as, vibrations, jolts and the like produced during travel. Additionally, external heat or improper filling of gas in the cylinder also has a bearing on the pressure build-up within the cylinder. The valve Rl is therefore provided to relieve the cylinder of gas pressure build-up above the first predetermined value. However, as the cylinder is subject to the various dynamic stresses referred to above, there could be the remote possibility of the valve Rl malfunctioning, in which case any uncontrolled excessive gas pressure build-up within the cylinder can well be hazardous. It is in such a situation that the valve R2, strategically located as aforesaid and preset at a second predetermined value slightly higher than the first predetermined value, comes into operation, to relieve excessive pressure build-up, by opening, whenever the pressure exceeds the second predetermined value. The second predetermined value at which the valve R2 is preset is higher than the first predetermined value at which the valve Rl is preset, in order to prevent R2 operating before giving a chance to Rl to operate, that is to say, to enable R2 to operate only if Rl fails to operate. In actual use of the system, the valve S is always kept open for free exit of gas from the cylinder outlet. By locating the valve R2 next to the outlet 0 (that is, between the valve S and the valve E) the valve R2 is always operable regardless as to whether the valve E is open or shut. This is because valve R2 is incorporated in the LPG line L downstream of the outlet O, next to the said outlet. In other words, the valve R2 is not influenced by any other component of the said system as long as valve S is open. It will be appreciated that the safety system proposed herein is not limited to the description set out herein, since other embodiments of the said system are possible within the scope and ambit of this invention. We Claim: 1. A safety system for excessive gas pressure in a two wheeler motor vehicle running on LPG, comprising a replaceable LPG cylinder rigidly accommodable in a housing provided for the vehicle, the cylinder being provided with a swivel valve and a built-in norm ally closed first pressure relief valve located on the cylinder body, such first pressure relief valve being preset to open whenever die gas pressure within the cylinder exceeds a first predetermined value, characterised by a normally closed second pressure relief valve incorporated in the LPG line downstream of the outlet of the said cylinder, next to the said outlet, the said second pressure relief valve being preset to open whenever the gas pressure within the cylinder exceeds a second predetermined value higher than the first predetermined value. 2. A safety system as claimed in Claim 1 wherein the second pressure relief valve is located between the swivel valve and an excess flow cum shut -off valve comprised in the said system. 3. A safety system for excessive gas pressure in a two wheeler motor vehicle running on LPG substantially as herein described with reference to, and as illustrated in, the accompanying drawings.

Documents:

0052-mas-2000 complete specification as granted.pdf

52-mas-2000-abstract.pdf

52-mas-2000-claims.pdf

52-mas-2000-correspondence others.pdf

52-mas-2000-correspondence po.pdf

52-mas-2000-description complete.pdf

52-mas-2000-drawings.pdf

52-mas-2000-form 1.pdf

52-mas-2000-form 19.pdf

52-mas-2000-form 26.pdf