| 摘要 |
PURPOSE:To measure the flow rate at a time of a low flow rate accurately, by inputting the output of a contactless type sensor of a piston type flowmeter into a comparator directly or through a sample and hold circuit, holding the sample and holding circuit by the output pulses, and counting said pulses. CONSTITUTION:When fuel is consumed and pressure difference is yielded between chambers 2a and 3a, a piston 4 is moved to the right in the Figure until the pressure difference becomes zero. The amount of the movement is converted into the change in inductance bya contactless type sensor 6, and its output is converted into a voltage proportional to the displacement of the piston 4 by a signal converter 11. The output of a comparator 16 is converted into a signal pulse by a monostable multivibrator 17, and the pulse is applied to a sample and hold circuit 15 and a counter 18. Therefore, the single pulse is generated from the monostable multivibrator 17 every time the flow rate with the minimum resolution enters a piston type flowmeter 7. The counter 18 counts the pulses. The counted value is added to a display 19, and the computed value of the flow rate is displayed by the display 19. |
