Glass based packaging and attachment of saw torque sensor
a technology of torque sensor and glass based packaging, which is applied in the direction of piezoelectric/electrostrictive transducers, generators/motors, instruments, etc., can solve the problems of high cost of such sensors, high quality of attachment technology specific to harsh environmental conditions, and failure to meet low cost requirements or functional requirements in terms of low stress introduced by the package, and achieve low cost , low cost, the effect of robust sensor operation
Inactive Publication Date: 2009-04-23
HONEYWELL INT INC
View PDF8 Cites 5 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
This approach enables cost-effective, flexible, and reliable torque monitoring with reduced stress and improved strain transmission fidelity, suitable for harsh automotive conditions.
Problems solved by technology
The measurement of torque on moving parts of an engine is, of course, the most challenging process, and involves wireless sensing and detector capability to withstand the automotive industry specifications of a much higher temperature and significant vibration.
Wireless optical and magnetic principles are frequently used, but the main disadvantages for these remains the high costs of such sensors and the quality of attachment technology specific to the harsh environmental conditions.
In the prior art, different SAW packaging solutions and attachment technologies have been tried, but they are not passing either the low cost requirement or functional requirement in term of low stress introduced by the package, primarily the technology used to attach the sensor.
Prior art technologies for SAW packaging and attachment to the substrate have suffered from being labor cost intensive.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0018]The present invention relates to both packaging quartz SAW sensors and attaching quartz SAW sensors to a shaft, as defined above, whether or not the sensor has been packaged according to this invention. FIG. 1 illustrates a perspective view of a sensor device generally 10 having a quartz SAW wafer 11 in which at least two SAW devices as is conventional. It is well known that quartz wafers have different thermal coefficients of expansion (TCE) in different crystalline directions.
[0019]A simple, conventional quartz SAW sensor will have two SAW devices electrically connected in parallel (resonator or delay line) located at 45 degrees with respect to an axis normal to the longitudinal axis of a rotating shaft. In the case of SAW resonators based torque sensors, for example, one sensor is exposed to tension stress and its operating frequency is decreasing, while the other sensor is exposed to compression and its operating frequency is increasing. Thus, the frequency difference expr...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| thickness | aaaaa | aaaaa |
| diameter | aaaaa | aaaaa |
| temperature | aaaaa | aaaaa |
Login to View More
Abstract
A glass cover wafer is bonded to a quartz SAW using glass frit technology, such that the glass wafer and glass frit formulation provides a thermal coefficient of expansion (TCE) of glass that fits the average TCE of the quartz in two perpendicular directions in a unique package. A dicing technology is used for chip separation. The sensor back side and the shaft are attached with a glass glue that transitions the TCE from the shaft to the quartz without interposing a large amount of the glue.
Description
FIELD OF THE INVENTION[0001]The present invention relates to a device for monitoring torque on rotating shafts. More particularly, the present invention relates to a torque monitoring device using a surface acoustic wave (SAW) devices.BACKGROUND OF THE INVENTION[0002]At the present time, there is an increased need for torque monitoring on rotating shafts in vehicles where improved operation is needed. It is desirable to measure torque for power train and drive line, and then include the sensing result in a closed loop operation for smooth, reliable operation and lower fuel use. In addition, torque monitoring can be of tremendous importance for the structural health monitoring (SHM) of different civil infrastructures and assets such as buildings, bridges, pumps and the like.[0003]Real time monitoring and predictive condition based maintenance practices are another place where torque sensors can be of value. The measurement of torque on moving parts of an engine is, of course, the mos...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Applications(United States)
IPC IPC(8): H02N1/04B32B38/04
CPCG01L3/10Y10T29/42Y10T156/1062
Inventor COBIANU, CORNELGEORGESCU, ION
Owner HONEYWELL INT INC