FORM2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention - A DEVICE FOR MIXING DIFFERENT FLUIDS
PRIOR TO DISPENSING INTO TANK/CONTAINER
2. Applicant(s)
(a) NAME : LARSEN & TOUBRO LIMITED
(b) NATIONALITY : An Indian company
(c) ADDRESS : L & T House, Ballard Estate, Mumbai 400 001,
State of Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

30 JUL 2008

TECHNICAL FIELD OF THE INVENTION
The present invention relates to a device for mixing fluids in variable mixing pump dispenser. More particularly, the invention relates to a mixing connector device for mixing fuels having variable densities or similar density, particularly, petrol and engine oils. However, mixing device of the invention can also be used in applications such as fuel mixing for required for any vehicle, any liquid mixing, juice making and the like.
BACKGROUND AND THE PRIOR ART
Two wheeler vehicles like bike, scooty and the like and any other vehicles require engine oil as lubricant. It needs to be mixed with Petrol. To fulfill this requirement, either engine oil is mixed in petrol after filling petrol in the vehicle tank or mixed together before filling inside the tank.
In variable mixing pump dispenser, two different fuels need to be mixed before dispensing through nozzles. But till date a simple arrangement for mixing of fuels prior to dispensing of fuel into the fuel tank of the vehicle is not reported.
US 4,069,835 discloses a device to proportionately mix fuel and lubricant for use in a two cycle engine which has no internal mixing device incorporated therewith comprising a cylindrical lubricant container, a columnar fuel delivery
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inlet which perpendicularly angles to merge with and to feed fuel into a conical funneled mixing chamber immediately below the base of the lubricant supply container. An axially secured butterfly lever in the line of fuel inlet travel is depressed by passing fuel and activates a spring-loaded piston valve which allows a proportionate flow of lubricant to the mixing chamber.
The common problem faced by the prior art and the existing technology is that simple arrangement for mixing fluid before dispensing and simultaneously dispensing the mixed fluid into the vehicle tank was not available. Moreover, the arrangements available in the market till date are expensive and complicated.
Thus there exists a need to provide for a device which would help in mixing two different fluids before dispensing into the tank of the vehicle.
The inventors have found that a device for mixing of different fluids can be designed such that mixture of two fluids can be formed before dispensing into the vehicle tank. Further the device would provide the operator to dispense fluid mixture at any angle without any interruption in dispensing operation.
OBJECTS OF THE INVENTION
Accordingly, one object of the present invention is to overcome the disadvantages of the prior art.
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Another object of the present invention is to provide a mixing device for easy and effective mixing of different fluids.
Another object of the present invention is to provide a mixing device which is cost effective.
Yet another object of the present invention is to provide ease of assembling.
Yet another object of the present invention is to provide ease of maintenance of the device.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a device for mixing different fluids prior to dispensing into tank of the vehicle, said device comprising:
a mixing chamber having flange portions on both sides;
at least two connector means being located on said flanges portions so as to allow inlet of fluids into the mixing chamber; and
an outlet means for dispensing out the mixed fluid
wherein said connector means comprises valve means being loaded with spring means such that opening and/or closing of the valve means is actuated by the fluid pressures in
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said connector means thereby allowing and/or disallowing flow of fluids from connector means into the mixing chamber.
The other objects and advantages of the present invention will be apparent from the description provided hereinbelow with reference to the accompanying figures and detailed description provided herein below.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a device for mixing different fluids. The device comprises a mixing chamber which has two flange like constructions on two sides which forms base for two inlet connector means adapted to passage of fluid into the mixing chamber. For describing the invention the fluids are considered as petrol and engine oil used in petrol pumps. However, this does not restrict the scope of the invention and any other fluids having different or similar densities can be mixed prior to dispensing into a container/tank.
The connector means comprise two inlet hose connector bodies which accepts the nozzles used for dispensing petrol and engine oil. The connector means comprises valve means located inside the connectors so as to control flow of fluids into the mixing chamber. The valves means used here are non-return valves whose movement is decided by the pressures of the fluids delivered from the nozzles. The fluid pressure is being transmitted to the non-return valves such that the non-return valve is moved to provide
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passage of flow of the fluid from the hose connectors to the mixing chamber. The non-return valves are located on spring means such that when the fluid pressure is transmitted to the valve, the valve moves pressing the spring. The springs used in the invention are compression springs which also help to position the valves to their original positions when the pressures of the fluids are less than the pressure initially exerted on the spring. Springs can be selected having different spring constants depending on the types of fluids and their densities. The non-return valve further comprises rubber gasket which provides sealing and prevent any flowing or leakage of fluid from the hose connectors to the mixing chamber or vice versa.
The mixing chamber comprises an outlet nozzle for dispensing out the mixed fluid into the container/tank. The device further comprises swivel connector means located around the outlet nozzle. The swivel connector means has hollow substantially cylindrical chamber means for accommodating the outlet nozzle such that the mixing device can perform rotation about 360° thereby providing flexibility in the dispensing operation.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 illustrates an isometric view of the mixing device of the present invention.
Figure 2 illustrates a cross-sectional view of the mixing device of the present invention.
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Figure 3 illustrates an exploded view of the mixing device of the present invention.
Figure 4 illustrates a cross section of the exploded view as shown in figure 3.
DETAILED DESCRIPTION OF THE ACCOMPANIYNG DRAWINGS
As shown in figures 1, 2, 3 and 4, mixing chamber (1) comprises inlet port flanges (2) which have hose connectors (3) on both sides. The mixing chamber (1) further comprises swivel connector (4) and outer nozzle (5). The hose connectors (3) comprises non-return valves (6) loaded with compression springs (7) . Rubber gaskets (8) are provided with the non-return valves (6) such that the gaskets provide sealing to the flow of fluids from the hose connectors (3) to the mixing chamber (1). Circlips (9) are provided at the outlet nozzle (5). Swivel connector (4) allows the outlet nozzle (5) to be located inside the hollow chamber (10) of the swivel connector (4). Rubber CD-ring (11) is provided around the outlet nozzle in the space between the outlet nozzle (5) and swivel connector means (4). Cross-holes (12) (also shown in figure 2) are provided on the outlet nozzle (5) .
General Working:
Variable post mix pump is used to dispense fuel after mixing two different fuels (Petrol + Engine oil) before
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delivery. To mix these fuels, it requires two different rubber hose for individual fuel (Fuel 1 & Fuel 2). The hose outlet of each fuel is connected to hose connector of mixing connector.
After lifting nozzle, Pump Electronics get signal to start the motor. At that time, fuel pressure at non-return valve inlet is less than fuel pressure and spring pressure at non return valve outlet. As soon as the nozzle lever is pressed, the pumping unit of petrol and engine oil suck the respective fuel from respective fuel tank. Then Petrol & Engine oil is flowing through respective metering unit, solenoid valve, outlet casting and hoses. Then both the fuels entered into hose connector of mixing connector from hose outlet.
The fuel pressure at non-return valve inlet is more than spring pressure. Due to this pressure difference, the Non return valve gets opened. The Fuel 1 (Petrol) & Fuel 2 (Engine oil) get mixed as soon as non-return valve is opened.
After completion of delivery into vehicle tank, the nozzle lever gets released. Due to this, The fuel pressure at non return valve inlet is less than fuel pressure and spring pressure at non return valve outlet. So, non-return valve gets closed. Non-return valve inlet port surfaces get sealed due to rubber gasket as shown in diagram. Then same operation gets repeated for each delivery.
The mixing connector is also having facility of single plane swivel at nozzle inlet side. It allows nozzle to
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rotate in 360°. Therefore this will help operator to handle nozzle easily. The operator can put nozz1e spout into mouth of vehicle tank in any angle. It is ease of handling.
Due to swivel action between swivel connector and mixer body, the friction takes place. So, the cross hole on the mixer body provides self-lubrication between swivel connector and mixer body with the help of same fuel. Therefore, the swivel connector rotates freely along the mixer body.
The structure thus conceived is adaptable to numerous modifications or variations. In practice the materials and dimensions may be dependant upon specific requirements and that will be comprised within its true spirit.
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WE CLAIM
1. A device for mixing different fluids prior to
dispensing into tank of the vehicle, said device
comprising :
a mixing chamber having flange portions on both sides;
at least two connector means being located on said flanges portions so as to allow inlet of fluids into the mixing chamber; and
an outlet means for dispensing out the mixed fluid
wherein said connector means comprises valve means being loaded with spring means such that opening and/or closing of the valve means is actuated by the fluid pressures in said connector means thereby allowing and/or disallowing flow of fluids from connector means into the mixing chamber.
2. Device as claimed in claim 1 wherein said valve means comprises non-return valves.
3. Device as claimed in claims 1 and 2 wherein said non¬return valves comprise rubber gasket adapted to provide sealing to the flow of fluid as the non-return valves return to their initial position after being actuated by increased pressure of the spring means.
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4. Device as claimed in claim 1 wherein said spring means comprises compression springs adapted to provide resilient motion to the non-return valves.
5. Device as claimed in claim 1 wherein said connectors means are hose connectors.
6. Device as claimed in claim 1 wherein said mixing chamber comprises cross holes for self lubrication.
7. Device as claimed in any of the preceding claims further comprises circlips.
8. Device as claimed in any of the preceding claims additionally comprises a swivel connector having hollow chamber such that the outlet nozzle can perform rotation of about 360° in a single plane.
9. Device as claimed in any preceding claims further comprises O-ring.
10. A device for mixing different fluids prior to dispensing into tank of the vehicle as herein substantially described and illustrated with reference to the accompanying figures.
Dated this 29th day of July 2008
Of S. Majumdar & Co. (Applicant's Agent)
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