FUEL PUMP

FIELD OF INVENTION The present invention relates to the field of instrumentation. More specifically the present invention is directed towards a portable apparatus for calibration of quantity of fuel injected by a diesel fuel pump.

BACKGROUND OF THE INVENTION

A fuel pump is an essential component of a diesel vehicle or other internal combustion engine device. Fuel has to be pumped from the fuel tank to the engine and delivered under low pressure to the engine or under high pressure to the fuel injection system. Some fuel injected engines have two fuel pumps: one low pressure/high volume supply pump in the tank and one high pressure/low volume pump on or near the engine.

There are many types of fuel pumps such as Mechanical pump, Electronic pump, Turbo pump and CRD1 pump.

All of them have different modes of action.

Electronic fuel injection (EFI) system utilizes an electric fuel pump, pressure regulator and return line to provide a constant fuel pressure differential across the injectors. This requires the fuel pressure to vary with manifold air pressure in both vacuum and boost phases of operation, with the excess fuel returning to the tank. Some fuel pumps run at 100% flow (full voltage) at all times while some systems reduce the voltage supply at low power to reduce heat, wear and noise. This is normally controlled by the engine control ECU, but may also have external drive modules or resistors to do the actual power control, In all cases the pump must be run at full voltage when testing the system so some form of controller by-pass may be required.

TESTING OF FUEL PUMP

One of the most important features of a fuel pump is the flow quantity being injected at a particular RPM and/or pressure of the pump.

Therefore whenever a fuel pump is to be installed in a vehicle, it needs to be tested and calibrated for fuel quantity efficiency.

CURRENTLY AVAILABLE SYSTEMS AND THEIR LIMITATIONS There are many methods and apparatus for testing and calibrating fuel discharge of all types of diesel fuel pumps. Such pumps may be used for vehicles (surface, water), generators or in common rail fuel systems for diesel engines. The fuel pump remains mounted on and driven by the engine. Currently testing of a fuel pump is done on a test bench which includes fuel flow rate testing with the help of flow sensors or graduated glass tubes. Such systems are commercially available in the market under various brands. However these suffer from the limitation of not being portable and are not cost effective. So all the fuel pumps which need to be tested and calibrated, have to be brought at the location where test bench is situated. This becomes a tedious effort.

Secondly the flow sensors being used are very costly if a good accuracy is required. So a device with cost effectiveness is required for use in our country which should not compromise the accuracy and the components of which are readily available.

Thirdly the graduated glass tubes are not accurate as parallax error may occur while taking reading on the glass tube. Size of the glass tubes is also too large. Small volumes cannot be measured using glass tubes and thus accuracy is less. Lastly, no apparatus for this particular application of calibration of diesel fuel pump, is available which has a feature of transmitting data related to various parameters such as fuel volume or temperature or pressure or RPM in a wireless manner.

INNOVATIVE SOLUTION PROPOSED BY THE INVENTOR In a correctly calibrated fuel pump, the weight of the fuel for every cylinder is preset as per the approved norms and parameters. Any deviation from the same indicates need for calibration to optimize the performance. The inventor of the present invention developed a portable apparatus for calibration of quantity of fuel injected by a diesel fuel pump of any type. The correctness of the quantity of fuel flowing into the engine is determined with the help of a 'load cell'. Weight of the fuel is sensed by a load cell and a specially designed electronic processor, processes the information and displays the quantity of fuel injected by diesel fuel pump through injectors as output on a screen with option for taking printout also. If there is any deviation from the preset norms, the nozzles are adjusted and calibrated to ensure accurate quantity of fuel.

The system is easy to use, cost-effective and accurate. It can be easily plugged into existing fuel pump test bench by replacing complex hardware and software mechanisms existing with pressure or volume measurement making it versatile and compatible with existing test benches. Therefore the present apparatus can be supplied as additional accessory for use in existing machines or as an integrated module with new machines.

OBJECTS OF THE INVENTION

The primary object of the present invention is to disclose a portable apparatus for calibration of quantity of fuel of diesel fuel pump of any type which senses the weight of the fuel being discharged and converts it into volume.

Another object of the present invention is to disclose a portable apparatus for calibration of fuel quantity of diesel fuel pump which can be fitted as an accessory with existing test bench by replacing the costly flow sensors. Yet another object of the present invention is to disclose a portable apparatus for calibration of fuel quantity of diesel fuel pump which DOES NOT use graduated glass tubes.

SUMMARY OF THE INVENTION

In present invention, the correctness of the quantity of fuel flowing into the engine is determined by a 'load cell' in which the weight of the fuel is sensed by an load cell , processed by a specially designed processing unit called analyzer and displayed as output on a screen with option for taking printout also. In a correctly calibrated fuel pump, the weight of the fuel for every cylinder is as per the set parameters. Any deviation from the same indicates need for calibration to optimize the performance. The system is easy to use, cost-effective and accurate. A major advantage offered by the system over prior art systems is easy portability, as the system is very compact. It can be easily plugged into existing diesel fuel pump test benches replacing glass test tubes normally used, making the process faster and more accurate. The apparatus can be supplied as additional accessory for use in existing machines or as an integrated module with new machines.

DESCRIPTION OF DRAWINGS:

Fig 1 : Complete representation of present invention

Numbering Details:

DETAILED DESCRIPTION OF THE INVENTION CONSTRUCTIONAL FEATURES The present invention essentially comprises a fuel pump driven by a motor and the said fuel pump is further connected to injectors with nozzles. The number of such injectors varies depending on the number of cylinders of the vehicle to which the fuel pump being tested, belongs. Usually the number of cylinders can vary from 1 to 12 from vehicle to vehicle, therefore the number of injectors with nozzles can also vary accordingly. The apparatus further comprises as many containers as are the injectors with nozzles.

Various models of the apparatus can be manufactured, each having different number of injectors with nozzles and different number of containers. The model which needs to be used for a fuel pump may be selected according to the vehicle thereby depending on the number of cylinders of that vehicle in which the said fuel pump is to be used. Each container rests on a load cell which senses the weight of fuel in the container and provides digital output signal accordingly.

This digital output of load cell is fed to a D/A converter and finally to an Electronic analyzer which converts the signal from load cell which is in fact the weight of fuel in the container, into volume of fuel which is in fact the volume of fuel being injected into the container through the injector with nozzles. The final output of the Electronic analyzer, in terms of volume of fuel being injected by the fuel pump, is displayed using a Mobile/Tablet application specially developed by the inventor. It can also be displayed on a computer or any other output device by using a modified software.

A RPM meter, temperature measuring device, a pressure gauge and stroke counter are also employed to monitor the parameters. The output signals from these devices are fed to the analyzer and further to a Mobile/Tablet or a computer using Bluetooth technology.

If the result displayed on Mobile/Tablet or computer output peripheral is not up to the mark and the volume of fuel is less or more than required, the same can be increased or decreased by changing the fuel pump pre -set settings according to the specifications provided by the fuel pump manufacturer and thereby the fuel quantity through the injector with nozzle can be varied. Thus the feature of calibration of the fuel pump is achieved.

For a reset function, where the containers need to be emptied for testing fuel pump parameters again and again or testing a new fuel pump, each container is connected to a drain pipe which is further connected to a NC Type solenoid valve. This NC type solenoid valve can be operated with the help of signal from Electronic analyzer with which it can be opened or closed. If the solenoid valve is opened, the fuel in all the containers is drained through fuel outlet.

In a preferred embodiment of the present invention, fuel pump for a six cylinder vehicle is being disclosed. Therefore number of container (6) and number of injector with nozzle (7) are selected as six, as shown in FIG 1. The number of 6 containers in the test apparatus of present invention is not fixed and apparatus can have containers corresponding to number of cylinders of the engine being tested which can be 1 or more.

WORKING OF THE INVENTION

Referring Fig 1, fuel pump (1) which is further connected to six number of Injectors with nozzles (5). These injectors with nozzles (5) inject fuel at preset pressure and temperature. Fuel Pump (1) injects some quantity of diesel fuel (F) in container (6). Then load cell (7) checks weight of fuel in cylinders (6). Load cell (7) measures the weight of the fuel (F) and gives output in the form of digital signal which is further converted into analog signal using D/A converter (8). D/A converter (8) reads load cell (7) data and transfers it to Programmable Electronic Analyzer (9). The Programmable Electronic Analyzer (9) is used to process signal from the load cell (7) and convert weight into volume. This processed data is then transferred to either a Bluetooth Module for Wireless Transmission to Mobile/Tablet application (10) for display on Mobile/Tablet (13) OR to Bluetooth Module for Wireless Transmission to computer software (11) for display on a computer (12). A USB printer (14) is also provided for normal page printing from Mobile/Tablet (13) or computer (12).

If there is any deviation from the preset norms, the pump (1) is adjusted and calibrated to ensure accurate quantity of fuel being injected by the fuel pump. To reset the apparatus for testing fuel pump parameters again and again or a new fuel pump, a mechanism using NC type solenoid valve is provided. Each container (6) is connected to a drain pipe which is further connected to a solenoid valve (15). This valve can be operated through software application loaded in mobile/Tablet/ Computer following which all containers that are filled with diesel are emptied. The complete apparatus can be easily plugged into existing fuel pump test bench or can be supplied as additional accessory for use in existing machines or as an integrated module with new test bench.

In the present invention, HX711 module is being used as D/A (digital to analog) converter (8) but any suitable D/A converter can be used. The Programmable Electronic Analyzer (9) being used is Arduino Mega board (9) but any suitable Programmable Electronic Analyzer can be used which can be programmed according to the need of the invention.

NOVELTY

Novelty lies in the fact that no prior art patent or publication discloses an apparatus for calibration of quantity of fuel injected by a diesel fuel pump which works on load cells. Existing systems used flow sensors or graduated glass tubes, to measure the volume of fuel. Flow sensors of good accuracy are quite expensive and the graduated glass tubes are not accurate as parallax error may occur while taking reading on the glass tube. Size of the glass tubes is also too large. Small volumes cannot be measured using glass tubes and thus accuracy is less.

In the present invention, the volume of fuel is being measured with the help of load cells and their signal is fed to an electronic analyzer which is programmed to convert this weight into volume. Since the cost of load cells is quite low as compared to the cost of flow sensors, the overall cost of the system is reduced drastically. The size of the apparatus is also reduced due to small size of load cells. The graduated glass tubes are also not required in the present invention. The apparatus thus becomes more accurate, low cost and portable. The complete output such as pressure, temperature, stroke and RPM along with the volume of fuel injected by the fuel pump being calibrated, can be transmitted wirelessly and displayed at suitable display device such as a tablet or a mobile or a computer.

No such apparatus is cited for a similar application in any of the prior art patents/publications.

INVENTIVE STEP The inventor has successfully designed and developed a portable apparatus for calibration of quantity of fuel of diesel fuel pump of any type. Inventive step lies in replacing the flow sensors or graduated glass tubes being used in existing systems, with load cell sensors in the present apparatus. Output of the load cell sensors is converted into analog signal using D/A converter. An Electronic Analyzer is so programmed that it analyses the data coming from the D/A converter and can give output in multiple forms such as display on a computer or on a mobile using Bluetooth technology. To achieve this, considerable effort has been put in developing software. Printed form of output is also possible. The inventor has achieved portability of the apparatus by making it a compact and plug in type of an apparatus which can be supplied as additional accessory for use in existing test bench machines or as an integrated module with new test bench machines. He has used electronics and computer software extensively to develop software applications which can work on handy mobile sets or computers commonly used by all these days.

The manner in which the parts have been integrated and functionaiized to achieve the desired technical result herein described is based on exhaustive research carried out by inventor.

INDUSTRIAL APPLICATION

The apparatus of the present invention is useful in automobile industry for calibrating fuel pump for fuel flow. Ail the diesel engines require this calibration apparatus. Being portable, low cost and user friendly, it can be easily used with existing test benches or can be manufactured and sold as an accessary. Thus a good potential for industrial application exists in this patent application.