Set rate gravimetric feeder

Claim 2

Apparatus comprising, a- a weigh belt system including a horizontally-disposed endless belt mounted between spaced pulleys, and a variable speed motor coupled to one of the pulleys, b- a pair of leaf springs Supporting the said system for pivotal displacement about a horizontal axis, c- a load cell coupled to the weigh belt system and providing an output signal in correspondence with pivotal displacement of said system, said load cell having an address button positioned below the said weigh belt system, d- a pair of pulley wheels rotatably mounted on the end portions of a rigid bar secured to the address button, e- a pair of arms secured to the weigh belt system and spanning the load cell, f- a flexible member passing over the said pulley wheels and having its'' ends secured to the free Ends of the said arms, and g- means controlling the speed of said motor in correspondence with the said output signal.

Claim 3

The invention as recited in claim 1, wherein said leaf springs are disposed on either side of the weigh belt system and lie in a plane containing the top portion of said belt.

Claim 4

The invention as recited in claim 1, including a spout for directing the flow of material onto the belt, said spout having a discharge opening of rectangular cross-sectional configuration and spaced from the belt surface.

Claim 5

The invention as recited in claim 3, wherein the said leaf springs are disposed on either side of the weigh belt system and lie in the plane containing the top portion of the belt, and wherein a vertical plane containing the pivot axis of the weigh belt system passes through the discharge opening of the spout.

Claim 6

The invention as recited in claim 4, wherein the said vertical plane passes through the spout discharge opening along a line located substantially 3 A/4 from the front wall of the spout, A being the width of the spout opening taken longitudinally of the belt.

Claim 7

The invention as recited in claim 5, including means for vibrating said spout in a substantially horizontal plane.

Claim 8

A set rate weigh belt feeder comprising, a- a frame carrying a pair of spaced pulleys, b- a horizontally-disposed endless belt passing over said pulleys, c- a variable speed motor carried by the frame and coupled to one of the pulleys, d- a tachometer carried by the frame and coupled to said motor, said tachometer producing a first voltage which varies in correspondence with the linear speed of the belt, e- a pair of leaf springs disposed on either side of the frame and supporting the frame for pivotal displacement about a horizontal axis, said leaf springs lying in the plane containing the top portion of the belt, f- means for directing the flow of material onto the top portion of the belt in the region of the leaf springs, g- a load cell for producing a second voltage which varies in correspondence with the weight of material on the belt, said load cell having an address button, h- a pair of pulley whels rotatably carried at the ends of a rigid bar secured to said address button, i- a pair of vertical arms spanning the said rigid bar and having upper ends secured to the said frame, j- a flexible wire passing over the said pulley wheels and having ends secured to the other ends of said vertical arms, k- means multiplying the said first and second voltages to produce a third voltage, which third voltage corresponds to the weight of material discharged by the belt per unit time, l- means providing a reference voltage corresponding to a predetermined set rate of the feeder, m- means comparing the said reference voltage with the said third voltage, and n- means changing the speed of the said motor in accordance with the difference between the said reference and third voltages.

Claim 9

A set rate weigh belt feeder comprising, a- a frame carrying a pair of spaced pulleys, b- a horizontally-disposed endless belt passing over said pulleys, c- a variable speed motor carried by the frame and coupled to one of the pulleys, d- a tachometer carried by the frame and coupled to said motor, said tachometer producing a first voltage which varies in correspondence with the linear speed of the belt, e- a pair of leaf springs disposed on either side of the frame and supporting the frame for pivotal displacement about a horizontal axis, said leaf springs lying in the plane containing the top portion of the belt, f- means for directing the flow of material onto the top portion of the belt in the region of the leaf springs, g- a load cell for producing a second voltage which varies in correspondence with the weight of material on the belt, said load cell having an address button, h- a pair of pulley whels rotatably carried at the ends of a rigid bar secured to said address button, i- a pair of vertical arms spanning the said rigid bar and having upper ends secured to the said frame, j- a flexible wire passing over the said pulley wheels and having ends secured to the other ends of said vertical arms, k- means multiplying the said first and second voltages to produce a third voltage, which third voltage corresponds to the weight of material discharged by the belt per unit time, l- means providing a reference voltage corresponding to a predetermined set rate of the feeder, m- means comparing the said reference voltage with the said third voltage, and n- means changing the speed of the said motor in accordance with the difference between the said reference and third voltages.

Claim 10

The invention as recited in claim 7, including an electro-mechanical gyrator carried by a concave member which terminates in said spout, said gyrator including eccentrically-mounted weights imparting horizontal vibrations to the conical member and spout when the gyrator is energized.