PATENT CLAIM ANALYSIS

Application Number: 16017917
Application Type: Utility
Filing Date: 2018-06
Publication Date: 2018-10
Patent Classification: ["073", "204260"]

Abstract:
The present invention disclosed a micromachined composite silicon flow sensor that is comprised of calorimetric flow sensing elements, time-of-flight sensing elements as well as independent temperature sensing element on a silicon-on-insulator device where the device layer is used for the thermal isolation membrane. The disclosed composite silicon flow sensor can measure mass flowrate, volumetric flowrate and flow medium temperature simultaneously, from which a full spectrum of flow parameters including flow pressure can be obtained. The sensor can be further used to alert any changes in physical properties of flow medium during operation. The disclosed manufacture process details the micromachining process of making such a sensor.

Claim (Index 1):
A MEMS silicon composite flow sensor comprising:\n one silicon-on-insulator (SOI) substrate; one thermally isolated suspending membrane across over an underneath cavity which is formed by a backside silicon bulk etching; wherein the suspending thermally isolated membrane are composed of three layers from bottom to top with an order of silicon dioxide, silicon, and silicon nitride; one micro-heater thermistor which is disposed centrally on top of the suspending thermally isolated membrane and used as a heating source; two calorimetric sensing thermistors which are disposed on top of the suspending thermally isolated membrane and on upstream and downstream locations along flow direction respective to the micro-heater thermistor; two time-of-flight sensing thermistors which are disposed on top of the suspending thermally isolated membrane and on upstream and downstream locations along flow direction respectively to the micro-heater thermistor with equal or unequal distance; and one ambient temperature sensing thermistor which is disposed on an area other than the suspending thermally isolated membrane area of the silicon-on-insulator substrate; wherein the thermistors are connected to a control electronics circuit, which is including one microcontroller, two demodulators, and flash memory to control the micro-heater thermistor and collect sensing signals from the calorimetric and time-of-flight sensing thermistors, and wherein the two calorimetric sensing themistors along with two external resistors in the control electronics unit are combined to form a Wheatstone bridge; wherein the MEMS silicon composite flow sensor utilizes the control electronics unit and connect to the two calorimetric sensing thermistors along with the micro-heater thermistor to measure mass flow rate of flow medium by elevating the micro-heater thermistor to a constant temperature; wherein the unbalanced temperature distribution due to flow movement will render resistance difference between the two calorimetric sensing thermistors; and wherein the resistance difference will unbalance the Wheatstone bridge and generate a voltage output which can be utilized to calibrate as the mass flow rate measurement; wherein the MEMS silicon composite flow sensors utilizes the control electronics circuit and connect to the two time-of-flight sensing thermistors along with the micro-heater thermistor to measure volume flow rate of flow medium by measuring phase shift of heat wave received on each of the time-of-flight sensing thermistors; wherein the heat wave is a sinusoidal function wave generated by the micro-heater thermistor; and wherein difference of the received phase shift signals of the heat wave on each of the time-of-flight sensing thermistors is processed by the demodulators of the control electronics unit, and which can be used to calibrate as volumetric flow rate measurement; and wherein the ambient temperature sensing thermistor is used to measure flow medium temperature, and wherein the flow medium pressure can be calculated by the measured data of flow medium temperature, the mass flow rate, and the volumetric flow rate.

Metadata:
- Claim Count in Document: 15.0
- Percentile: 94.0
- Lexical Diversity: 1.62319
- Patent Class: 73.0
- Transitional Phrase Type: open
- Component Type: 1
- Foreign Priority: False
- Related Applications: ['13736941', '13035639', '13847045', '15380035', '11774771']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.687721766102611
- 35 USC 102 Novelty (BERT): 0.513867339791987
- Combined Prediction Score: 0.6703363234715486
- Mean Citation Score: 276.61884
- Max Citation Score: 296.56
- Similarity Product: 226.086818113327

Labels:
- Claim Label 101: 1
- Claim Label 102: 1
- Claim Label 103: 1
- Claim Label 112: 0
- Combined Label: 1
- Label 101 Adjusted: 1

Dataset: test