FORM - 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
SAFETY CAP FOR LPG CYLINDERS
HINDUSTAN PETROLEUM CORPORATION LIMITED
an Indian Company of 17, Jamshedji Tata Road, Mumbai - 400020,
Maharashtra, India.
and
INDIAN INSTITUTE OF SCIENCE
an Indian Organization,
of IP Cell, Society for Innovation and Development (SID),
IISc, Bangalore - 560012,
Karnataka, India.
The following specification particularly describes the nature of the invention.

FIELD OF THE INVENTION
The present invention relates to safety devices used for Liquefied Petroleum Gas (LPG) cylinders. Particularly, the present invention relates to a safety cap for LPG cylinders.
BACKGROUND OF THE INVENTION
LPG cylinders are provided with valves which are self closing type. Such valves do not open unless an external pressure is applied. External pressure is applied by a pressure regulator fitted on top of the cylinder when cylinder is being used. The cylinder valves are provided with safety caps. Safety caps are designed to withstand high pressures. If due to some reasons the cylinder valve is not functioning properly, and the pressurized LPG is escaping or leaking, the safety cap provided on the valve, prevents this leakage. Also the safety cap prevents any foreign particulate material from being deposited on and in the valve during transportation of cylinders or when cylinder is not in use.
The safety cap is mounted on the valve of a cylinder and is held in place by means of springs. To remove the safety cap the spring need to be pulled to release the spring grip on the valve neck. Typically, a nylon cord is connected to a spring. By pulling the cord, the spring looses the grip on valve neck & cap can be removed.
The safety cap currently used is not very easy to remove. Pulling the nylon cord to release the spring tension requires a considerable amount of force and most of the users find it difficult to remove the cap. Thus there

is a need for an economically designed safety cap which is easy to remove.
OBJECTS OF THE INVENTION
An object of the present invention is to provide a safety cap for LPG cylinders that requires comparatively less amount of force to remove the safety cap.
Another object of the present invention is to provide a safety cap for LPG cylinders that is adapted to withstand high pressure.
Yet another object of the present invention is to provide a safety cap for LPGcylinders that is adapted to retian clamp load even during, vibrations fatigue or joint relaxation.
Still another object of the present invention is to provide a safety cap for LPG cylinders that is easy to use and operate.
One more object of the present invention is to provide a safety cap for LPG cylinders that is ergonomically designed.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention there is provided a safety cap for Liquefied Petroleum Gas (LPG) cylinders. The safety cap includes a main body, a spring member and a cam lever. The main body includes an internal stub and a groove. The internal stub of the cap fits on a cylinder valve. The groove is configured on the main body at the external portion to hold the spring & puts a limit on the forward

movement of the spring more than the requirement. The spring member is slidably fitted in the groove. The cam lever is connected to the spring member and adapted to lock and unlock the safety cap to the cylinder valve. The cam lever and the spring member are adapted to facilitate spring-back action for configuring locking of the safety cap to the cylinder valve.
In one embodiment of the present invention, the main body is of a synthetic polymeric material.
Typically, the safety cap includes a cord adapted to connect the safety cap to the cylinder valve.
Typically, the cord is of Polyproplene.
Preferably, length of the cord is adapted to facilitate positioning of the safety cap within limits of stay plates of the LPG cylinder, when the safety cap is in unlocked position.
Furthermore, the cam lever has an aperture configured thereon for facilitating connection of the cam lever to the spring member.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The invention will now be described in relation to the accompanying drawings in which,

Figure 1 illustrates a perspective view of a safety cap removably fitted on a LPG cylinder valve, in accordance with one embodiment of the present invention;
Figures 2a illustrates a top view of a main body of the safety cap of Figure 1;
Figure 2b illustrates a sectional view of the main body of Figure 2a;
Figure 2c illustrates a front view of the main body of the safety cap of
Figure 1; -
Figure 2d illustrates a sectional view of the main body of Figure 2c;
Figure 3a illustrates a front view of a spring member of the safety cap of Figure 1;
Figure 3b illustrates a top view of the spring member of Figure 3a;
Figure 3c illustrates a side view of the spring member of Figure 3a;
Figure 4a illustrates a front view of a cam lever of the safety cap of Figure 1; and
Figure 4b illustrates a side view of the cam lever of Figure 4a.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Preferred embodiments will now be described in detail with reference to the accompanying drawings. The preferred embodiments do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.
The present invention envisages a safety cap for removably fitting on a LPG cylinder valve. The safety cap of the present invention is adapted to be easily fitted and removed from the cylinder valve without any trouble to a user. The safety cap of the present invention is adapted facilitate spring-back action for configuring locking the safety cap to the cylinder valve.
Referring to Figure 1, a safety cap 100 for removably fitting on a LPG cylinder valve 102 is illustrated. The safety cap 100 includes a main body 104, a spring member 106 and a cam lever 108.
Referring to Figure 1 and Figure 2a to Figure 2d,, the main body 104 includes an internal stub 110 (shown in Figure 2d) and a groove 112. The internal stub 110 is adapted to be removably fitted on the cylinder valve 102. The groove 112 is configured on the main body 104. In one embodiment of the. present invention, the main body 104 is of a synthetic polymeric material. However, the present invention is not limited to any particular material used for manufacturing the main body 104. Alternatively, the main body 104 may be manufactured of various other materials known in the art. Referring to Figure 1 and Figure 3a to 3c, the spring member 106 is disclosed. The spring member 106 is adapted to be

slidably fitted in the groove 112. The spring member 106 is adapted to facilitate secure locking of the safety cap 100 on the cylinder valve 102.
Referring to Figure 1 and Figure 4a to 4b, the cam lever 108 is illustrated. The cam lever 108 is connected to the spring member 106. The cam lever 108 is adapted to lock and unlock the safety cap 100 to the cylinder valve 102. The cam lever 108 includes an aperture 114 configured thereon for facilitating connection of the spring member 106 to the cam lever 108. The cam lever 108 and the spring member 106 are adapted to facilitate spring-back action for configuring locking of the safety cap 100 to the cylinder valve 102.' In other words, the cam lever 108 is spring loaded by means the spring member 106 to facilitate spring-back action for configuring self locking of the safety cap 100 to the cylinder valve 102.
The safety cap 100 of the present invention also include a cord 116 adapted to connect the safety cap 100 to the cylinder valve 102. The cord 116 may be connected to the main body 104 by means of an apertured attaching means (not shown) configured on the main body 104. The cord 116 facilitates retaining of the safety cap 100 to the LPG cylinder. In one embodiment of the present invention, the cord 116 is of nylon. However, the present invention is not limited to any particular material used for manufacturing the cord 116. Alternatively, the cord 116 may be manufactured of various other materials known in the art. In one embodiment of the present invention, length of the cord 116 is adapted to facilitate positioning of the safety cap 100 within limits of stay plates of the LPG cylinder, when the safety cap 100 is in unlocked position. Accordingly, such positioning of the safety cap 100 within limits of stay plates of the LPG cylinder reduces breaking of the safety cap 100 while the LPG cylinders are moving on chain conveyors in plants.

In one embodiment of the present invention, the weight of the safety cap 100 without the spring member 106 and the cam lever 108 is about 5.6 gm to 6.0 gm. However, the present invention is not limited to any particular weight of the safety cap 100. Further, in one embodiment of the present invention the safety cap 100 is adapted to withstand a pneumatic pressure of at least 17 kg/cm2. However, the present invention is not limited to withstanding any particular pressure limit. Furthermore, in one embodiment of the present invention, the safety cap 100 may be manufactured from various materials such as Dopont Derlin 500, Tenac 5010 or Celcon M90/M140. However, the present invention is not limited to any particular material used for manufacturing the safety cap 100.
In use, for removing the safety cap 100 from the cylinder valve 102, the cam lever 108 is pulled/ lifted. Pulling/lifting of the cam lever 108 pulls the spring member 106, subsequently releasing the grip of the spring member 106 on the cylinder valve 102. Thus, releasing of the grip of the spring member 106 on the cylinder valve 102 releases the safety cap 100 and the safety cap 100 may be removed easily. Further, for replacing the safety cap 100 on the cylinder valve 102, the safety cap 100 needs to be pushed on the cylinder valve 102. The cam lever 108 being spring loaded automatically regains its operative locked state and thus securely hold the safety cap 100 on the cylinder valve 102.
TECHNICAL ADVANCEMENTS AND ECONOMIC
SIGNIFICANCE
The safety cap for LPG cylinders of the present invention is adapted to withstand high pressure. Further, the safety cap is adapted to retain clamp load even during vibration, fatigue or joint relaxation. Furthermore, the

safety cap is easy to use and operate. Additionally, the safety cap is economically designed. Also, the safety cap of the present invention requires comparatively less amount of force to remove the safety cap...
The numeral values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention and the claims unless there is a statement in the specification to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other changes in the preferred embodiment as well as other embodiments of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

We claim:
1. A safety cap for Liquefied Petroleum Gas (LPG) cylinders,
said safety cap comprising:
a) a main body consisting of,
• an internal stub adapted to be removably fitted on a cylinder valve; and
• a groove configured on said main body;

b) a spring member slidably fitted in said groove; and
c) a cam lever connected to said spring member and adapted to lock and unlock said safety cap to said cylinder valve, wherein said cam lever and said spring member are adapted to facilitate spring-back action for configuring locking of said safety cap to said cylinder valve.

2. The safety cap as claimed in claim 1, wherein said main body is of a synthetic polymeric material.
3. The safety cap as claimed in claim 1, further comprising a cord adapted to connect said safety cap to said cylinder valve.
4. The safety cap as claimed in claim 3, wherein said cord is of nylon.
5. The safety cap as claimed in claim 3, wherein length of said cord is adapted to facilitate positioning of said safety cap within limits of stay plates of said LPG cylinder, when said safety cap is in unlocked position.

6. The safety cap as claimed in claim I, wherein said cam lever has an aperture configured thereon for facilitating connection of said cam lever to said spring member.