Abstract: An adjustable tangent assembly for a positive displacement diaphragm gas meter is provided with a cam on the stroke adjuster. Use of the cam results in a linear relationship between angular movement of the stroke adjuster and the stroke adjustment.

Abstract: A method and means for measuring a characteristic, in particular one associated with particle size, of any of the feed, underflow or overflow streams of a hydrocyclone is provided. Information as to the flowrate and density of the feed stream as well as the angle of flare or other related variable associated with the shape of the underflow stream are fed to processing means which applies a formula or algorithm, which is usually empirically derived, to such information to provide a value of the required characteristic. The characteristic may be related to particle size, particle size distribution in any of the streams or the liquid content or the flowrates of solids or liquids in the underflow or overflow. Measurement apparatus comprising a dedicated hydrocyclone is also provided.

Abstract: A method is disclosed of controlling the operation of a hydro-cyclone or a circuit embodying same. The method involves the measurement of a variable associated with the shape of the slurry underflow emanating from the hydro-cyclone outlet. The variable is generally the cone angle or, in effect, the radius or diameter of the conical shaped stream of slurry flowing from the outlet at a selected position below the outlet and this diameter can be measured using an arm or arms which operatively rides on the outer boundary of the slurry underflow stream.

Abstract: A temperature compensating tangent assembly for a diaphragm gas meter wherein the movement of the tangent wrist is controlled to be other than linearly radial in order to maintain the timing of the valves.

Abstract: A calibration system for a mechanical gas volume corrector which has a first shaft turned at a rate corresponding to the otherwise uncorrected volumetric flow rate through the meter, a second shaft, a variable ratio transmission coupled between the first and second shafts, and a mechanism for altering the ratio of the transmission in response to changes of a physical condition of the gas. The calibration system includes an arrangement for applying a representation of a reference state of the physical condition to the ratio altering mechanism, and indicator for indicating a fixed number of revolutions of one of the shafts, an arrangement for determining the number of revolutions of the other of the shafts corresponding to the fixed number of revolutions of the one shaft, and a calculator for determining and displaying the ratio of the other shaft revolution number to the fixed number.

Abstract: A temperature compensator for gas meters is comprised of two serially connected bi-metallic elements extending between the tangent post and the drive shaft from the flow responsive element. The bimetallic elements are reversely oriented whereby each element responds to a given temperature change to produce movement in the same direction as the other with respect to the axis of the drive shaft.

Abstract: An adjustable tangent assembly for a positive displacement diaphragm gas meter is provided with a pair of concentric face gears coaxial with the axis of rotation of the crank shaft and accessible through a small plug hole in the meter cover. An adjusting tool inserted through the plug hole allows independent self locking adjustment of the timing and stroke with high resolution.

Abstract: In a diaphragm type gas meter, one crank plate pivotally mounting a pair of diaphragm movement transmission levers and the other crank plate pivotally mounting a pair of valve actuating levers overlap each other rockably around the central axis of a crank shaft. The relative angular position of the two plates is controlled e.g. by an eccentric cam. On a diaphragm control wall member for restricting the stroke end of the reciprocation of each measuring diaphragm of said gas meter are formed two inclined diaphragm control surfaces with different angles of inclination. Further, on a lower casing of the gas meter is integrally die-cast a partition wall with triangular section flush with the top surface of the lower casing and defining a discharge-side valve chamber and a discharge passage.

Abstract: A gas meter temperature compensating tangent device having a tangent block to which is adjustably connected a tangent arm for journaling a crankshaft. The tangent block has a guideway formed in alignment with the axial line of the tangent arm. A plurality of nested "U" shaped bi-metal strips have one end pivotably connected to the tangent block and the other end connected to a tangent wrist which is slideably disposed in the guideway. The bi-metal strips will sense temperature changes in the gas and force the tangent wrist to slide in the guideway to increase or decrease the distance between the tangent wrist and the crankshaft.The tangent device provides improved accurate deflection due to temperature changes as a result of built-in radial rigidity of the tangent wrist relative to the tangent arm.