ADDED-FLUID-METERING SYSTEM

• US 3,593,966 A
• Filed: 09/24/1969
• Issued: 07/20/1971
• Est. Priority Date: 09/24/1969
• Status: Expired due to Term

• Current Assignee: Lonnie E. Munroe
• Original Assignee: Lonnie E. Munroe
• Inventors: Munroe, Lonnie E.
• Application Number:
  US04/860,637
• Time in Patent Office: 664 Days
• US Class Current: 366/40
• CPC Class Codes: B28C 7/026 by measuring data of the driving system, e.g. rotational speed, torque, consumed power

Abstract

A system for monitoring and controlling the addition of water to dry concrete mix. The water is added through a solenoidcontrolled supply valve to a truck-mounted mixing container rotatable by a three-phase AC motor. The power consumption of the motor, which decreases as water is added to the mix, is monitored by a load sensor transducer which produces a related DC control signal. A voltage comparator and latching circuit are provided to deenergize the solenoid and stop water flow when the DC control signal voltage equals a precalibrated DC reference voltage.

Claims

1. An added-fluid-metering system comprising an electric control value for selectively controlling the flow of fluid from a fluid source to a load, electric motor means for conditioning the load, transducer means for monitoring the power consumption of said motor due to the load and producing an indicating signal in response thereto, means for producing a second signal corresponding to a desired fluid value, comparator means responsive to said indicating signal and said second signal for producing a trigger signal when the magnitude of said indicating signal exceeds the magnitude of said record signal, and latching circuit means responsive to said trigger signal for selectively operating said control valve.

2. A fluid-metering system as described in claim 1 further including a mix-ready-indicating lamp, a source and timing circuit means responsive to said trigger signal for supplying said source to said lamp.

3. An added-fluid-metering system as described in claim 1 wherein said motor is adapted to be energized from a three-phase supply and said transducer means includes probe means for sensing the current supplied to a first phase of said motor and producing a third signal proportional thereto, transformer means for sensing the voltage supplied to the first phase of said motor and producing a fourth signal proportional thereto, and storage means for combining the in-phase portions of said third and fourth signals to produce said DC indicating signal.

4. A metering system as described in claim 3 further including a wet-enough-indicating lamp and circuit means for energizing said lamp in response to said trigger signal.

5. Apparatus for monItoring and controlling the flow of liquid into an electrically motor-driven mixer wherein the introduction of liquid into the mixer affects the power required to drive the motor for the mixer, and the amount of such power required is related to the amount of liquid in the mixer, said apparatus comprising conduit means adapted to connect said mixer to a liquid supply including an electrically operable valve means placeable selectively in open and closed states, transducer means adapted to be operatively connected to said motor operable to produce an indicating signal which reflects the level of power supplied to the motor, circuit means operatively interconnecting said transducer and said valve means, operative with said transducer producing an indicating signal reflecting power supplied the motor above a certain level to place said valve means in one of its said states, and with said transducer producing an indicating signal reflecting power supplied the motor below said certain level to place said valve means in its other state.

6. Apparatus as described in claim 5 wherein the introduction of liquid into the mixer decreases the power required to drive the motor and wherein said valve means is open in its said one state and closed in its other state.

7. Apparatus as described in claim 6 further including adjustable means for establishing said certain power level.

8. Apparatus as described in claim 7 wherein the indicating signal produced by said transducer means comprises a DC voltage, said adjustable means produces a DC reference voltage, and said circuit means further includes a comparator responsive to said DC voltage and said DC reference voltage for controlling the states of said valve means.

9. Apparatus as described in claim 8 wherein said comparator places said valve means in an open state when the magnitude of said DC voltage exceeds the magnitude of said DC reference voltage and places said valve means in a closed state when the magnitude of said DC voltage is less than the magnitude of said DC reference voltage.