Sensor for measurement of temperature and pressure for a cyclic process

• US 8,986,205 B2
• Filed: 05/16/2011
• Issued: 03/24/2015
• Est. Priority Date: 05/14/2010
• Status: Expired due to Fees

• Current Assignee: Frederick J. Buja
• Original Assignee: Frederick J. Buja
• Inventors: Buja, Frederick J.
• Primary Examiner(s): Thomson, William
• Assistant Examiner(s): Archer, Marie
• Application Number:
  US13/108,906
• Publication Number:
  US 20110282163A1
• Time in Patent Office: 1,408 Days
• US Class Current: 600/300
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/0271 Thermal or temperature sensors
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: A61B 5/682 Mouth, e.g., oral cavity; tongue; Lips; Teeth
• CPC Class Codes: B29C 2043/5808 pressure or compressing force
• CPC Class Codes: B29C 2043/5816 temperature
• CPC Class Codes: B29C 43/58 Measuring, controlling or regulating for bank adjustment in calendering B29C43/245
• CPC Class Codes: G01K 13/20 Clinical contact thermometers for use with humans or animals
• CPC Class Codes: G01K 2211/00 Thermometers based on nanotechnology
• CPC Class Codes: G01K 7/02 using thermoelectric elements, e.g. thermocouples
• CPC Class Codes: G01K 7/06 the thermoelectric materials being arranged one within the other with the junction at one end exposed to the object, e.g. sheathed type

Abstract

Disclosed is a multi-variable sensor and systems and methods for its use to sense process changes or variations. The sensor is employed to concurrently sense a plurality of parameters (e.g., temperature and pressure) for a process.

Claims

1. A method for concurrently sensing a combined temperature and pressure of a process over time, using a single sensor, comprising:

sensing a plurality of cycles of the process using a single micro-bead sensor in direct contact with a flow of a material in the process, including placing a sensor consisting of two dissimilar metal wires terminated by a generally-spherical, micro-bead junction in a path of the flowing material;

exposing the micro-bead junction to the process, wherein the micro-bead junction is responsive to material flow in the process and produces a signal in response to the process;

receiving the signal;

converting the signal to data representing at least temperature and pressure using at least one reference point against which the sensor was calibrated; and

at least temporarily, storing data representing the temperature and pressure in memory;

wherein the sensing and receiving of the signal occurs at a rate less than one-half that of a period of the process cycle.

2. The method according to claim 1, wherein the rate of sensing and receiving the signal is less than one-tenth of the average process cycle.

3. The method according to claim 2, wherein converting the signal to data representing at least temperature and pressure in produces a first output representing a digital temperature change (T_emf) and a second output representing a pressure change (P_emf) due to bead compression relative to the at least one reference point, where a sum of the signals represents the combination of the temperature change and pressure change from the at least one reference point.

4. The method according to claim 3, wherein the reference point temperature and pressure are both below the temperature and pressure of the process aspects being sensed and where the temperature change and pressure change are both positive.

5. The method according to claim 2, wherein the rate of sensing and receiving the signal is less than one-tenth of an average process cycle and where variations in the timing and sequence of the cycle are accurately detected.

6. The method according to claim 1, wherein the process is a manufacturing process employing a mold and where the sensor is applied to the mold at a location selected from the group consisting of:

a mold cavity vent;

a slot in the mold;

in contact with the material being molded;

an aperture through which molding material flows;

a mold flow controlling mechanism;

an ejector pin;

a mold cavity;

stationary pin;

machine nozzle retaining hole; and

a mold cavity plate.

7. The method according to claim 1, wherein providing a sensor consisting of two dissimilar metal wires includes a termination process selected from the group consisting of:

welding;

laser welding;

friction welding;

electron beam welding; and

fusing.

8. The method according to claim 1, further comprising producing the generally-spherical, micro-bead junction of the sensor wherein sensitivity of the micro-bead junction is inversely related to a diameter of the micro-bead.

9. The method according to claim 1 wherein the micro-bead junction is at least partially covered with a flexible coating prior to exposure to the cyclic process.

10. A system to concurrently measure at least temperature and pressure of a cyclic process using a common sensor, comprising:

at least one sensor consisting of a generally spherical micro-bead junction formed from dissimilar metals, said micro-bead sensor being exposed to material flowing in the process, wherein the sensor produces a signal in response to the flow of material in the process;

electrical circuitry to receive a sensor output signal and convert the sensor output signal to a digital signal;

a processor for receiving the digital signal and processing the received digital signal in order to quantify at least temperature and pressure components of the signal relative to at least one reference point against which the sensor was calibrated, the processor correcting for the reference point to produce an output representing at least two parameters.

11. The system according to claim 10, wherein said processor, using the at least one reference point, produces a first output representing a digital temperature change (T_emf) and a second output representing a pressure change (P_emf) due to bead compression wherein a sum of the T_emf and P_emf represents the combination of the temperature change and pressure change determined relative to the at least one reference point.

12. The system according to claim 10, wherein a sensitivity of the micro-bead junction is inversely related to a diameter of the micro-bead.