High overpressure low range pressure sensor
First Claim
1. A pressure sensor comprising a base plate, a diaphragm plate including a rim secured to the base plate, and a central diaphragm web section that is deflectable under force toward the base plate comprising;
- a plurality of posts formed on one of said plates in registry with the deflectable web section, and forming stops when the deflectable web section is deflected toward the base plate a preselected amount, said plurality of posts being integrally formed with said deflectable web section of said diaphragm and having ends which engage the base plate for forming the stops.
1 Assignment
0 Petitions
Accused Products
Abstract
A low range pressure sensor includes a base plate of brittle material, and a diaphragm plate mounted on the base plate and sealed around a periphery to the base plate. Pressures are introduced to cause the diaphragm to deflect toward the base plate, and the deflection of the diaphragm is sensed through strain gauges to provide an indication of the pressure. The diaphragm is provided with a plurality of individual support posts on a side facing the base plate, so that when the diaphragm is deflected toward the base plate under high overpressures the support posts will support the diaphragm against movement to avoid failure or breakage of the diaphragm. The number of support posts can be varied as desired. In a preferred form of the invention, the base plate is provided with a very thin layer of silicon dioxide, which is a good electrical insulator and which also serves to help accommodate slight movement of the support posts as they touch the surface of the base plate to reduce stress buildup in the diaphragm as the overpressure increases.
44 Citations
11 Claims
-
1. A pressure sensor comprising a base plate, a diaphragm plate including a rim secured to the base plate, and a central diaphragm web section that is deflectable under force toward the base plate comprising;
a plurality of posts formed on one of said plates in registry with the deflectable web section, and forming stops when the deflectable web section is deflected toward the base plate a preselected amount, said plurality of posts being integrally formed with said deflectable web section of said diaphragm and having ends which engage the base plate for forming the stops. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
8. A pressure sensor comprising a base plate, a diaphragm plate including a rim secured to the base plate, and a central diaphragm web section that is deflectable under force toward the base plate comprising;
a plurality of posts formed on one of said plates in registry with the deflectable web section, and forming stops when the deflectable web section is deflected toward the base plate a preselected amount, the plurality of posts comprising at least four posts on the diaphragm web section. - View Dependent Claims (9)
-
10. A pressure sensor comprising a base plate having a central portion, a diaphragm plate including a rim secured to the base plate, and a central diaphragm portion having a deflectable web section deflectable under force toward the base plate, comprising;
-
a plurality of posts formed on one of said plates in registry with the deflectable web section, and forming stops when the deflectable web section is deflected toward the base plate a preselected amount; the plate other than the one plate having a surface facing the posts, which surface is recessed a greater depth in central portions of the other plate than at edges thereof. - View Dependent Claims (11)
-
Specification