An apparatus for controlling the metering of additives which are to be blended with a primary substance includes an element which determines how much additive is being discharged from an additive storage container. This element includes a weight detecting device which detects a first portion of the additive contained in a metering container and includes another weight detecting device for detecting the weight of a second portion of the additive contained in an inventory container which feeds the additive into the metering container. This element also includes a volumetric flow rate monitoring device for monitoring the flow rate of a liquid additive. Each of these detecting and monitoring devices generates respective electrical signals proportional to the respective monitored conditions. The apparatus also includes an element for sensing how much of the primary substance is being discharged from a primary substance container. This element includes both a main flowmeter which detects the actual rate of flow and a device for simulating a flow rate. Proportional electrical signals are generated by the flow meter and the flow rate simulating device. The apparatus also includes a control circuit which uses the electrical signals to control the amount of additive which is discharged and added to the primary substance. This determination is made based on data which is entered into the apparatus by means of manually actuated switches and keys. Control signals are generated by a microprocessor and associated program.

Additive metering control system

Disclosed herein is an automatically controlled weigh feeding apparatus including a container for prefilling with a substance, a device for discharging the substance from the container at a controllable rate, apparatus for weighing the substance being discharged and for producing an electrical signal proportional to that weight, a voltage to frequency converter connected to receive the electrical signals, a digital computer, apparatus coupled to an output of the voltage to frequency converter for inputting data signals to the digital computer, the computer being adapted to compute a corrective signal based on the input data signals received, and coupling apparatus coupled between the computer and the device for discharging the substance from the container for controlling the rate of discharge responsive to the corrective signal.

Weigh feeding apparatus

Disclosed herein is an automatically controlled weigh feeding apparatus including a container prefilled with a substance, a device for discharging the substance from the container at a controllable weight, apparatus for weighing the container and its contents and for producing an electrical signal proportional to that weight, a first amplifier for amplifying the electrical signal, a first analog-digital converter coupled to said first amplifier and a digital computer coupled to said first analog-digital converter for computing the weight of substance remaining in the container. A second amplifier is coupled to said first amplifier and a ramp off-set circuit which is controlled by the digital computer inputs a second signal to the second amplifier means having a controlled stepping output applied as a second input signal to the second amplifier to maintain the output of the second amplifier within a given selected range of amplitude during one time cycle of operation. A second analog-digital converter interposed between the second amplifier and the digital computer. The digital computer is adapted to compute a corrective signal based on the signal received for controlling the discharge of the substance from the container.

Weigh feeder system

Apparatus for controlling the rate of flow of a powdered solid material such as flour, comprising a load cell supporting an inclined plate onto which the flour particles impinge after falling through an inclined gate valve. The output of the load cell is fed to a control circuit including a direct proportional control section and an integrated error section with a monitor circuit sensitive to excessive integrated errors. The control circuit acts on an electric motor controlling the opening of the gate valve to maintain a predetermined rate of flow.

Flow control systems

A portable apparatus for controlling the production of a mixture of a fluid and a plurality of additives utilizes a unified control panel having all of the necessary controls compactly contained in a single housing for providing both automatic and manual control of each of the additive channels through which the additives are mixed with the primary fluid. The control of each additive channel is achieved through a software controlled algorithm by which errors are only incrementally, rather than totally, applied to prior drive signals at any one time.

Apparatus and method for mixing a plurality of substances

A control system is provided for stopping the operation of a bulk material conveyor system in response to an indication that the speed of either drive or driven elements thereof are above or below acceptable amounts, that the output speed of a particular material handling component falls below an acceptable difference from the input speed to said component, or that the speed of an upstream material handling component falls outside an acceptable difference with respect to the speed of a downstream material handling component feeding material to said upstream component. Speed indication is provided by the electrical signal output from dc tachometer-generators associated with the drive or driven shafts of the component whose speed is being sensed. The signals are, in turn, transmitted to the input networks of speed comparators; there being one such comparator for each comparison to be made with each such speed comparator incorporating an integrated circuit operational amplifier and an emitter follower power amplifier connected as a comparator circuit with hysteresis. A reed relay also incorporated in the speed comparator, operates in response to a signal from said comparator circuit indicative of improper material handling component operation to effect stoppage of the conveyor system.

Conveyor overspeed-underspeed and/or slip detector

Constant weight feeding apparatus

The batch weighing system disclosed herein for successively weighing out pre-selected ingredients in a batch formula has a modularized weight controller circuit in which pre-set voltages control the weights of ingredients or materials making up the batch and in which a skeleton network is selectively built up by using logic card modules to provide selected combinations of the following functions: automatic, compensated cutoff of each ingredient delivered to the scale hopper, delivery of each ingredient to the scale hopper at a full flow feed rate and a dribble feed rate, overweight and underweight checking of each delivered ingredient, partial batch control for delivering only a selected percentage of each ingredient to reduce the total weight of the batch while retaining the proper proportions of the ingredients in a given formula, an automatic tare to facilitate the use of non-accumulative weight selection devices, and a maximum batch size control to provide an indication if the scale capacity is exceeded.

Gerald C Mayer

Papers

Conveyor overspeed-underspeed and/or slip detector

Constant weight feeding apparatus

Automatic batch weigher

Fluid metering process and apparatus

Automatic batch and checkweighing apparatus