Method and apparatus for ultrasonic temperature monitoring

• US 20030001299A1
• Filed: 06/29/2001
• Published: 01/02/2003
• Est. Priority Date: 06/29/2001
• Status: Abandoned Application

• Current Assignee: Superior Graphite Company, University of Chicago The (University of Chicago)
• Original Assignee: University of Chicago
• Inventors: Gopalsami, Nachappa, Chien, Hual-Te
• Application Number:
  US09/897,832
• Publication Number:
  US 20030001299A1
• Time in Patent Office: Days
• US Class Current: 264/40.1
• CPC Class Codes: B30B 11/005 Control arrangements

Abstract

A non-intrusive method of determining temperature and for controlling the Electroconsolidation process is described which is based on the change with temperature of the velocity of sound as it passes through a material. Ultrasonic transducers located outside of the die, but positioned to transmit and receive an ultrasonic signal, are used to determine an average temperature in the line of sight of the transmitted signal. A single-loop feedback system may be used to control the temperature based upon a comparison of the measured temperature to the desired temperature.

Claims

1. In an Electroconsolidation apparatus having a die cylinder, first and second hydraulically-actuated, conductive rams slidably received in opposite ends of the die cylinder;

first and second electrical leads in conductive contact with the first and second rams, respectively, the electrical leads being attached to a source of electrical power; and

an electrically-conductive, pressure-transmitting medium disposed within the cylinder between the rams;

the improvement comprising;

an apparatus for measuring the temperature within the die including a transmitting transducer associated with one of the first and second rams;

a receiving transducer associated with the other of the first and second rams, the transmitting transducer and the receiving transducer being spaced apart a distance within a predetermined range;

a signal generator associated with the transmitting transducer for creating a tone that is transmitted from the transmitting transducer to the receiving transducer;

whereby the temperature of the electrically-conductive, pressure-transmitting medium is calculated by measuring the time of flight of a tone created by the signal generator between the transmitting transducer and the receiving transducer.

2. The apparatus of claim 1 wherein the improvement further comprises a water-cooled electrical contact interposed between each of the first and second electrical leads and its associated ram, each of the transmitting transducer and receiving transducer being located within its water-cooled contact.

3. The apparatus of claim 1 further comprising a control circuit for controlling the amount of electrical power directed to the conductive rams through the electrical leads.

4. The apparatus of claim 3 wherein the control circuit comprises a single-loop feedback that compares an input temperature to the calculated temperature.

5. The apparatus of claim 4 further comprising a controller that adjusts the amount of electrical power directed to the conductive rams based upon a comparison of the input temperature to the calculated temperature.

6. A method for determining the temperature within an Electroconsolidation apparatus having a die cylinder, first and second hydraulically-actuated, conductive rams slidably received in opposite ends of the die cylinder;

first and second electrical leads in conductive contact with the first and second rams, respectively, the electrical leads being attached to a source of electrical power; and

an electrically-conductive, pressure-transmitting medium disposed within the cylinder between the rams;

the method comprising;

providing a transmitting transducer associated with one of the first and second rams;

providing a receiving transducer associated with the other of the first and second rams, the transmitting transducer and the receiving transducer being spaced apart a distance within a predetermined range;

providing a signal generator associated with the transmitting transducer;

creating a tone that is transmitted from the transmitting transducer to the receiving transducer;

measuring the time of flight of the tone created by the signal generator between the transmitting transducer and the receiving transducer;

calculating the velocity of sound between the transmitting transducer and receiving transducer by dividing the distance between the transducers by the time of flight; and

calculating the temperature of the electrically-conductive, pressure transmitting medium.

7. The method of claim 6 further comprising providing a water-cooled electrical contact interposed between each of the first and second electrical leads and its associated ram, each of the transmitting transducer and receiving transducer being located within its water-cooled contact.

8. An apparatus for determining the temperature of within a medium comprising:

a transmitting transducer located exteriorly of the medium on one side thereof;

a receiving transducer located exteriorly of the medium on a side opposite to that on which the transmitting transducer is located;

a signal generator associated with the transmitting transducer for creating a tone that is transmitted from the transmitting transducer to the receiving transducer;

whereby the temperature of the medium is calculated by measuring the time of flight of a tone created by the signal generator between the transmitting transducer and the receiving transducer.