专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明授权

US4932255A Flow sensing using surface acoustic waves 失效
标题翻译：使用表面声波的流量感测
公开(公告)号：US4932255A
公开(公告)日：1990-06-12
申请号：US285625
申请日：1988-12-16
申请人： John G. Brace , Thomas S. Sanfelippo
发明人： John G. Brace , Thomas S. Sanfelippo
IPC分类号： G01F1/00 , G01F1/66 , G01F1/68 , G01F1/688 , G01F1/69 , G01N29/02 , G01P5/12
CPC分类号： G01F1/66 , G01F1/6882 , G01N29/022 , G01N2291/0256 , G01N2291/02836 , G01N2291/0423 , Y10S73/04
摘要： A sensor employs a SAW oscillator heated above the ambient by converting RF energy to heat via acoustic dissipation in energy absorbers located outside the path of propagation. The oscillator utilizes a delay line designed to support single mode operation, fabricated on a substrate. Low insertion loss results from placing the energy absorbers outside the propagation path. Thermally conductive paths around the substrate periphery reduce thermal gradients. Used to measure fluid flow, fluid is directed across the SAW delay line lowering the substrate temperature which is elevated by the heat generating energy absorbers outside the propagation path. The temperature reduction changes the oscillator frequency, indicative of the gas velocity. In operation, gases are passed across the top of the delay-line while liquids are passed across the bottom of the delay-line in a back-side sensing operation. To measure gas or vapor contaminants, chemically sensitive coatings placed on the substrate in the propagation path can be used to sense contaminants in a gas flowing over the substrate. In mass flow sensing applications a difference frequency between an oscillator with a delay-line having end absorbers and operating at elevated temperatures and a reference oscillator with a delay-line operating at ambient is determined.
摘要翻译：传感器采用通过在位于传播路径之外的能量吸收器中的声学耗散将RF能量转换成热量的高于环境的SAW振荡器。振荡器利用设计用于支持在基板上制造的单模操作的延迟线。通过将能量吸收器放置在传播路径之外，导致低插入损耗。衬底周围的导热路径降低了热梯度。用于测量流体流动，流体被引导穿过SAW延迟线，降低由传播路径外部的发热能量吸收体升高的衬底温度。温度降低会改变振荡器频率，指示气体速度。在操作中，气体通过延迟线的顶部，而液体在背面感测操作中通过延迟线的底部。为了测量气体或蒸汽污染物，传播路径中放置在基板上的化学敏感性涂层可用于检测在衬底上流动的气体中的污染物。在质量流量感测应用中，确定具有端部吸收器的延迟线并且在升高的温度下工作的振荡器与具有在环境温度下工作的延迟线的参考振荡器之间的差频。

2. 发明授权

US5051645A Acoustic wave H.sub.2 O phase-change sensor capable of self-cleaning and distinguishing air, water, dew, frost and ice 失效
标题翻译：声波H2 O相变传感器，能够自我清洁，区分空气，水，露水，霜冻和冰
公开(公告)号：US5051645A
公开(公告)日：1991-09-24
申请号：US472125
申请日：1990-01-30
申请人： John G. Brace , Thomas S. Sanfelippo
发明人： John G. Brace , Thomas S. Sanfelippo
IPC分类号： G01N29/02
CPC分类号： G01N29/022 , G01N2291/0251 , G01N2291/0423
摘要： A surface-acoustic-wave (SAW) H.sub.2 O phase-change sensor capable of distinguishing air, water, dew, frost and ice. The sensor can also distinguish various frost thicknesses. The sensor has a size allowing batch fabrication of the chips, and allowing the device to fit in small spaces such as between fins of an evaporator. The sensor is fabricated on a strong piezoelectric substrate with a short acoustic path length. The SAW phase-change sensor experiences large changes in insertion loss and impedance upon deposition of water in various phases. The sensor has a hydrophobic surface treatment covering the SAW sensor surface, and if placed in a vertical position will self-clean during a refrigeration defrost cycle.
摘要翻译：表面声波（SAW）H2O相变传感器，能够区分空气，水，露水，霜冻和冰。传感器还可以区分各种霜冻厚度。传感器具有允许批量制造芯片的尺寸，并允许该装置安装在诸如蒸发器的翅片之间的小空间中。传感器制造在具有短声道长度的强压电基片上。 SAW相变传感器在各种相中的水沉积时经历插入损耗和阻抗的大的变化。传感器具有覆盖SAW传感器表面的疏水表面处理，并且如果放置在垂直位置，则在制冷除霜循环期间将自清洁。

3. 发明授权

US4726225A Surface acoustic wave gas flow rate sensor with self-heating feature 失效
标题翻译：具有自热特性的表面声波气体流量传感器
公开(公告)号：US4726225A
公开(公告)日：1988-02-23
申请号：US899439
申请日：1986-08-22
申请人： John G. Brace , Thomas S. Sanfelippo
发明人： John G. Brace , Thomas S. Sanfelippo
IPC分类号： G01F1/68 , G01F1/66 , G01F1/688 , G01F1/69 , G01N29/00 , G01N29/02
CPC分类号： G01F1/66 , G01F1/6882 , G01N2291/02836 , Y10S73/04
摘要： A surface acoustic wave device for measuring the mass flow rate of a gas includes a surface acoustic wave delay line formed of a piezoelectric substrate and having a temperature coefficient of delay on the order of 10.sup.-4 /.degree.C. The substrate has disposed thereon a transmitting and a receiving interdigital transducer, the transducers being configured to have an operating frequency in the range of from 10MHz to 1000MHz. That portion of the substrate located between the transducers defines a propagation region and has a medium deposited thereon for absorbing a portion of the acoustical and/or electrical energy flowing thereacross. This absorbed energy increases the temperature of the propagation region over that of the surrounding ambient.A mass flow of the gas across the sensor will decrease its temperature and result in an upward shift in the resonant frequency. A suitable amplifier and resonant frequency detector may be coupled to the sensor for detecting the change in resonant frequency, thereby permitting mass flow rate measurement.
摘要翻译：用于测量气体的质量流量的声表面波装置包括由压电基片形成并具有约10-4 /℃的延迟温度系数的声表面波延迟线。基板上设置有发射和接收叉指式换能器，所述换能器被配置为具有在10MHz至1000MHz范围内的工作频率。位于换能器之间的衬底的该部分限定了传播区域并且具有沉积在其上的介质，用于吸收在其上流动的一部分声学和/或电能。这种吸收的能量增加了传播区域的温度超过周围环境的温度。通过传感器的气体的质量流量将降低其温度并导致谐振频率向上移动。合适的放大器和谐振频率检测器可以耦合到传感器，用于检测谐振频率的变化，从而允许质量流量测量。

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式