Patent ID: 9689768
Date: 2017-06-27
CPC Classifications: G01L

Claim:
1. A pressure difference sensor, comprising: a pressure difference measuring cell, which has a measuring cell platform having a first measuring chamber and a second measuring chamber in its interior, said measuring chambers are separated from one another by a measuring membrane, said measuring cell platform has on a first measuring chamber side a first planar mounting surface facing away from the measuring membrane, and on a second measuring chamber side a second planar mounting surface facing away from the measuring membrane, said measuring chambers have, in each case, a measuring chamber opening to the first, respectively second, planar mounting surface, via which they are contactable with a first, respectively second, pressure, said measuring membrane is elastically deformable as a function of a difference between the first pressure in said first measuring chamber and the second pressure in said second measuring chamber; a transducer for providing a signal dependent on the deformation of said measuring membrane; a first reinforcement element having a first planar reinforcement area, wherein there extends through said first planar reinforcement element a first pressure duct, which opens into the first reinforcement area and communicates with the first measuring chamber opening, said first reinforcement area is connected pressure bearingly with said first mounting surface; and a second reinforcement element having a second planar reinforcement area, wherein there extends through said second planar reinforcement element a second pressure duct, which opens into said second reinforcement area and communicates with said second measuring chamber opening, said second reinforcement area is connected pressure bearingly with said second mounting surface, wherein: a deflection of said first and said second mounting surfaces due to a pressure loading of said first and said second measuring chambers is lessened by said reinforcement elements to no greater than 25%, especially no greater than 10%, preferably no greater than 5%, further preferably no greater than 2% and especially preferably no greater than 1% of the deflection of said mounting surfaces of a pressure difference measuring cell of same type without connection with said reinforcement elements; at least 50%, preferably at least 70%, further preferably at least 85% and especially preferably at least 95% of an effective stiffness K=1/(dx/dp) of said reinforcement element connected by the pressure difference measuring cell is provided only by these connections of said reinforcement element with said measuring cell platform without additional connections between said reinforcement elements in a parallel branch, wherein x is the separation between said first mounting surface and said second mounting surface having the greatest pressure dependence dx/dp.