Mass flow rate meter

Claim 2

A flow meter in accordance with claim 1 in which the flow directing means includes a guide member having at least a portion thereof positioned intermediate the discharge lip of said distributor means and the impact surface of said sensor.

Claim 3

A flow meter in accordance with claim 1 in which the distributor means has a downwardly inclined surface terminating at the discharge lip and in which the inclined surface of said distributor means extends in a direction substantially normal to the inclined impact surface of said sensor.

Claim 4

A flow meter in accordance with claim 1 in which said distributor means further includes means for limiting the initial downwardly directed velocity of the particulate material leaving the discharge lip of said distributor means.

Claim 5

A flow meter in accordance with claim 1 in which common support means is provided for said distributor means, said flow directing means and said sensor, a vertical conduit is provided to carry the particulate material to and from said flow meter, and means mounting said common support means for movement relative to said vertical conduit to permit movement of said flow meter into and out of said conduit without interrupting flow of the particulate material through said conduit.

Claim 6

The flow meter defined in claim 1 including: means providing downwardly inclined slots in said sensor impact surface; and means for introducing air interiorly of the sensor to exit through said slots to aid material flow over the sensor surface.

Claim 7

Apparatus as recited in claim 1 and further comprising means for rotating said sensor about its vertical axis.

Claim 8

The flow meter defined in claim 1 including: said sensor impact surface providing a relatively sharper angle at said impact area where first engaged by the falling material and a relatively flatter angle where the material leaves the sensor surface.

Claim 9

Apparatus as recited in claim 1 in which said means opposing downward movement of the sensor is an adjustable spring.

Claim 10

Apparatus as recited in cLaim 1 including: means including a lever mechanism for transmitting the motion of said sensor to an indicator.

Claim 11

Apparatus as recited in claim 1 and further comprising: means for forcing said sensor impact surface in an upward direction; and servo means connected between said means responsive to movement of the sensor and said forcing means to cause said forcing means to maintain the sensor substantially in its undeflected position.

Claim 12

Apparatus as recited in claim 1 including: a flange on the lower edge of said sensor impact surface adapted to retain particulate material of sufficient depth to protect said impact surface.

Claim 13

Apparatus as recited in claim 1 in which said sensor impact surface is substantially conical.

Claim 14

Apparatus as recited in claim 1 in which said sensor impact surface is a multisided pyramid.

Claim 15

A flow meter for measuring the mass rate of flow of particulate material, a sensor having an inclined impact surface, means mounting said sensor for movement only in a straight line vertical direction excluding rotational movement about a definite axis, means opposing downward movement of said sensor, distributor means for dropping the particulate material whose mass rate of flow is to be measured onto said sensor impact surface at a substantially definite impact velocity to exert a downward force on the sensor having no movement to rotate the sensor bodily about a definite axis, said distributor means including a downwardly sloping member having a central opening therethrough and a vertical sleeve positioned interiorly of the central opening of said downwardly sloping member and providing a vertical surface against which the material is directed to cause the material to fall substantially the same vertical height on the sensor impact surface regardless of the rate of flow of the material, and means responsive to the force on said sensor and thereby responsive to said mass flow rate independently of the lateral position of the point of impact of said material on the sensor impact surface as long as said definite impact velocity of said particulate material remains the same for indicating said mass rate of flow.

Claim 16

A flow meter in accordance with claim 16 in which said vertical sleeve is in the form of an axial guidetube extending through the central opening of said spreader and downwardly into close proximity with said sensor impact surface to limit inward movement of the particulate material.

Claim 17

A flow meter as recited in claim 16 including: means for limiting the initial velocity of said particulate material comprising a baffle for applying particulate material to said spreader, positioned and oriented to cause said particulate material to turn through substantially 90*.

Claim 18

The flow meter defined in claim 16 including: means for introducing air into said vertical sleeve to exit between the bottom of the sleeve and the sensor impact surface to inhibit the accumulation of material on the sensor impact surface adjacent the bottom of the sleeve.

Claim 19

Apparatus as recited in claim 17 and further comprising: a skirt extending downward surrounding said guide tube and into the region of said sensor impact surface to limit outward movement of said particulate material.

Claim 20

A flow meter for measuring the mass rate of flow of particulate material comprising: a sensor having an inclined impact surface; means mounting said sensor for substantially vertical movement; means opposing downward movement of said sensor; means for dropping particulate material, whose mass rate of flow is to be measured, through a predetermined distance of free fall onto said impact surface to generate a downward force on the sensor; means for measuring the downward force on the sensor and thereby the mass rate of flow through the meter; a vertical guide surface above the sensor impact surface; and means for directing the flow of particulate material against said veRtical guide surface at substantially all rates of flow so that the material strikes the impact surface at substantially the same height to make the distance of free fall substantially independent of the rate of flow.

Claim 21

The flow meter defined in claim 21 including: said sensor mounting means restricting it to straight line, vertical movement only.

Claim 22

The flow meter defined in claim 21 in which: said vertical guide surface is provided by an inner sleeve extending vertically downward to a position adjacent the sensor impact surface; and said directing means comprises an inclined spreader at the outside of said sleeve and directing the material inwardly against the sleeve surface.

Claim 23

The flow meter defined in claim 23 including: a central baffle above said spreader and having the baffle surface inclined at substantially 90* to the spreader surface for interrupting the vertical component of velocity of flow above the spreader.

Claim 24

The flow meter defined in claim 23 including: means for introducing air into said sleeve to exit between the bottom end of the sleeve and the adjacent sensor impact surface to inhibit the accumulation of material on the sensor surface adjacent the bottom of the sleeve.

Claim 25

The flow meter defined in claim 21 in which: said vertical guide surface is provided by an outer sleeve extending downward to a position adjacent the sensor impact surface; and said directing means comprises a central inclined baffle directing the material outwardly against the sleeve surface.

Claim 26

A flow meter for measuring the mass rate of flow of particulate material comprising: a sensor having an inclined impact surface, distributor means spaced above said sensor and terminating in a discharge lip for dropping the particulate material whose mass rate of flow is to be measured onto said sensor, the discharge lip of said distributor means positioned in a substantially horizontal predetermined plane, the impact surface of said sensor having a predetermined impact area in the form of a narrow elongated band substantially parallel to the plane of the discharge lip of said distributor means, flow directing means to direct the fall of the particulate material passing over the discharge lip of said distributor onto the said predetermined impact area of said sensor impact surface so that individual particles of said particulate material strike the impact surface at substantially the same velocity as each other particle and that the same proportion of the velocity head of each particle is converted to a downward impulse of force on the sensor, and a force balance supporting the sensor in a predetermined position to measure the downward force exerted on the sensor by the particulate material and thereby the mass rate of flow of particulate material through the meter, said force balance operable to resist downward movement of the sensor due to the impact of the particulate material on said sensor and maintain said sensor in substantially said predetermined position.