Patent ID: 8417470

Claim:
A security pulse generator being applied in a fuel dispenser having a flow measuring transducer and a control main board, on which there is a measuring microprocessor, said security pulse generator comprising: a pulse signal generating component, which is applied to generate a corresponding pulse signal according to rotation of the flow measuring transducer; an encoding microprocessor, which receives and transduces said pulse signal, and transmits said pulse signal to said control main board, in the meanwhile said encoding microprocessor counts and encodes said pulse signal; a measuring microprocessor, which receives output pulse number encoded data from said encoding microprocessor and decodes said data to get an output pulse number, wherein, an output pulse signal that said control main board collects and the count encoding microprocessor outputs is directly implemented by the measuring microprocessor or the pulse count number component on said control main board and is transmitted to the measuring microprocessor, said measuring microprocessor comparing the decoded pulse number to the pulse number counted by the control main board to determine if there are suspected frauds in the fueling process; wherein said pulse signal generating component is a photoelectric or electromagnetic one, and wherein the photoelectric pulse signal generating component comprises an optical grating encoder, which is installed on a spindle that is connected to the flow measuring transducer and rotates therewith, of which the rotating circle number is proportional to flow volume; said electromagnetic pulse signal generating component comprising a magnetic steel body as the magnetic field generating component which is installed on the spindle that is connected to the flow measuring transducer and rotates therewith, of which the rotating circle number is proportional to the flow volume; wherein said electromagnetic pulse signal generating component further comprises a programmable magnetic rotary encoder chip, which inducts magnetic field distribution of said magnetic steel body to transmit two circuit output pulse signals after the chip is processed.