GB304704A - Improvements in liquid level indicators - Google Patents

Abstract

304,704. Lewis, W W., and Economic Car Light, Ltd. Sept. 22, 1927. Indicators actuated by pressure of head of liquid.-In a liquid-level indicator applicable to fuel tanks of motor vehicles, of the kind in which the air pressure in an open ended pipe dipping into the liquid is measured, a block A of ebonite is provided with a chamber B containing mercury, into which projects an iron pipe C communicating through a. passage D with the dip pipe. A bell E dips into the mercury and by means of a rack E<1> on its stem actuates a spindle F<1> carrying an indicating pointer. The top of the bell carries a cap H which is pressed upwards by a loose ring I and spring J. A transverse spindle M, actuated by an external handle, carries cams N engaging the cap H, N<1> engaging the ring I, and N<2> engaging a depending arm L‹ attached to a spring L carrying a pad L<1> closing the top of a pipe K. To take a reading, the spindle M is turned to depress the bell and expel air from the dip pipe, and a further rotation disengages the cam N from the cap H while the cam N<1> keeps the ring I depressed and allows the bell to move freely under the influence of pressure within. To renew the air in the system when required, the spindle M is turned to raise the arm L‹, spring L, and pad L<1> by the cam N<2>, while the ring I is also released and the bell raised to its hightest point by the spring J, the whole system being open to atmosphere through pipe K. Further rotation of the spindle M enables a reading to be taken as before. The scale reading is adjustable by a spindle P screwing into an auxiliary mercury reservoir O.