By Jim-Rex Lawson MOSES
A fuel dispenser is a machine at a filling station that is used to pump gasoline, diesel, ethanol fuel, kerosene, or other types of fuel into vehicles. The first gasoline pump otherwise known as fuel dispenser was invented and sold by Sylvanus F. Bowser in Fort Wayne, Indiana on September 5, 1885.
But this pump was not used for automobiles, as they had not been invented yet. Instead, it was used for some kerosene lamps and stoves. He later improved upon the pump by adding safety measures, and also by adding a hose to directly dispense fuel into automobiles.
For a while, the term bowser was used to refer to a vertical gasoline pump. The term is still used in Australia and New Zealand, Petrol pumps in Commonwealth countries, and gas pumps in North America. Many early gasoline pumps had a calibrated glass cylinder on top.
The desired quantity of fuel was pumped up into the cylinder as indicated by the calibration. Then the pumping was stopped and the gasoline was let out into the customer’s tank by gravity. When metering pumps came into use, a small glass globe with a turbine inside replaced the measuring cylinder but assured the customer that gasoline really was flowing into the tank.
A modern fuel dispenser is logically divided into two main parts — an electronic “head” containing an embedded computer to control the action of the pump, drive the pump’s displays, and communicate to an indoor sales system; and secondly, the mechanical section which in a ‘self contained’ unit has an electric motor, pumping unit, meters, pulsars and valves to physically pump and control the fuel flow.
In some cases the actual pump may be sealed and immersed inside the fuel tanks on a site, in which case it is known as a submersible pump. In general submersible solutions in Europe are installed in hotter countries, where suction pumps may have problems overcoming cavitation with warm fuels or when the distance from tank to pump is longer than a suction pump can manage.
In modern pumps, the major variations are in the number of hoses or grades they can dispense, the physical shape, and the addition of extra devices such as pay at the pump devices and attendant “tag” readers.
Nozzles are attached to the pump via flexible hoses, allowing them to be placed into the vehicle’s filling inlet. The hoses are robust to survive hardships such as being driven over, and are often attached using heavy spring or coil arrangements to provide additional strength. The nozzles are usually color coded to indicate which grade of fuel they dispense, however the color coding differs between countries or even retailers.
One of the most important functions for the pump is to accurately measure the amount of fuel pumped. Flow measurement is almost always done by a 4 stroke piston meter connected to an electronic encoder. In older gas pumps, the meter is physically coupled to reeled meters, while newer pumps turn the meters movement into electrical pulses using a rotary encoder.
The technology for communicating with gas pumps from a point of sale or other controller varies widely, involving a variety of hardware and proprietary software protocols. Traditionally these variations gave pump manufacturers a natural tie-in for their own point-of-sale systems, since only they understood the protocols. An effort to standardize this in the 1990s resulted in the International Forecourt Standards Forum, which has had considerable success in Europe.
Understanding the Modern Fuel Dispensing Machine
Since their origin, pumps have been artfully streamlined into designs aesthetically appealing and crafted with mechanical precision, controlled by rapidly advancing computer technology, giving drivers alternative ways of paying for their purchases. Today’s dispensers make it easy to pay and pump at the same time, relieving the need to deal with an attendant. Dispensers used today have much higher flow rates, which means customers, can get on their way quickly.
Flow rate means the time it takes a mechanism located in an underground tank to pump a certain quantity of gasoline or diesel through a dispenser. In present day world the pump lies deep in a tank and is hooked to every dispenser, making the dispenser very smooth and quiet.”
Understanding the Modern Fuel Dispensing Machine/ Components of a Fuel Dispenser
A typical fuel dispensing station has a complicated system of tanks, pipes and computer technology. A meter underground sits large tanks that hold between 25,000 and 50,000 liters of various grades and types of fuel. When the customer selects a grade, fuel begins to travel from the tank to his or her vehicle.
There are two prominent types of pumps which are used for pumping this fuel namely suction pumps or submersible pumps. The fuel hurtles up through the system, emptying into a flow meter – a chamber that could be made out of cast iron or aluminum, depending on the machine.
As it flows through the metering chamber into the hose connected to the vehicle, a complex gear system tells the computer exactly how much fuel is being dispensed. This gear system consists of the Positive Displacement (PD) meter and the counter which have been explained in further detail in the subsequent paragraph. A fuel dispensing pump has three main components.
The first is a pump that actually pumps the gasoline out of the tank. The second is the PD meter, or a positive Displacement Meter that the gasoline flows through. It works a bit like a revolving door in a way that every revolution of the revolving door a fixed very accurate volume of gasoline goes through it. The speed of the pump may vary but the PD meter will always measure an exact quantity of gasoline.
The gas gets pushed through the meter, and there are going to be pistons or a simple rotor that is going to turn. For every turn of the rotor, there is a certain measurement depending on the meter, and that measurement is going to then signal to the register in front of you how many Naira and how much volume have gone through. This is the third part which is a counter that takes the information from the PD meter and converts it into litters and Naira and Kobo.
There is a system which works to detect as to when the tank is full. It works by sending small pulses of gasoline through the line. If there is still air in the tank, the pulses are dissipated in the tank, if the tank is full; the pulse is returned through the hose and detected. When the return pulse is detected it stops the pump.
One of the major difference between the fuel dispensers used today and the earlier ones is the mode used to pump in the fuel, though the motors used and the billing system has not undergone any significant changes but the earlier dispensing machines were more manual it terms that the lever needs to be released once the tank is full else the oil spills over. But today’s dispensers automatically stop the fuel outflow once the tank is full.
Billing Mechanism in Fuel Dispensers
The billing mechanism in fuel dispensing systems is controlled by Mechanical or Electronic meter registers. These registers make up the gasoline pump computer which is responsible for the functioning of the entire billing mechanism of a fuel dispensing systems. The minimum price increments that can be made for each unit sale and the maximum sale that can be recorded vary between different models of the gasoline pump converter, for e.g.: in case of VR-10 gasoline pump converter provides N97.00 per revolution.
This entire unit is a microprocessor based device, where the per unit price is maintained in the microprocessor registers and based on the logic incorporated and the quantity of fuel consumed it increases the counter of the register and displays the price on the analog or digital billing screens of the dispensing machine. External devices quite often make use of asynchronous serial communication protocol to communicate with the billing unit.
Types of Fuel Dispensing System
There are different parameters based on which fuel dispensing machines are classified right from the type of fuel pump used say suction pumps or submersible pumps, as multi fuel or single fuel dispensing machine, based on the technical specification of the pumps. Pertaining to our reference the most prominent way to classify would be as a touch screen machine where in the dispensing machine acts as a POS terminal to be self operated by the consumer and a normal fuel dispensing machine.
Back End Servers and Dispensing Machines
There are different modes which are used to communicate between the fuel dispensing system and the back end servers which would be used to store and process the data; this could be through secure IP network, through LAN or telephone line connection to communicate between the unit placed on the dispensing machine and the back end servers. In certain instances the overhead device on the fuel dispensing machine would transmit the messages to a host computer through a serial communications port.
Fuel Dispenser’s of Future
The fuel dispenser’s of the future are expectedly supposed to be much more user friendly than the ones available today. They supposedly would provide enhanced multimedia services by using features like touch screen monitors (some of which are already in the market). These would be innovative POS solutions, not only would it be easy for the consumers to buy fuel, but would also give an opportunity to the vendors to promote additional offers and services.
Motorists can also gain extra value by accessing information such as traffic news and weather while refueling at the Multimedia Dispensing Solution. These innovative dispensers would use touch screen technology to help users access the extensive functionality of the dispensers, and navigate the many options and functions quickly while refueling.
These laminated sensors senses touch by detecting capacitance changes in an array of micro gauge capacitors embedded within the body of the laminate. Hence in time to come though the internal mechanism of fuel dispensing machines are not expected to change, but revolutionary changes are expected in the way end customers interacts and uses these machines.