Attenuating mass for an ultrasonic sensor, use of epoxy resin
View Patent ↗Temperature stability at the temperatures prevailing in a motor and stability that is required over an entire temperature range are provided by an attenuating mass. This enables continuous use at temperatures of approximately 150° C. while providing ultrasonic attenuation at low temperatures.
1. An attenuating mass adapted to be soft and stable in a temperature interval of −30° C. to 150° C., comprising:
an epoxy resin matrix; and
a filler with a multimodal grain size distribution, wherein the filler is dispersed throughout the resin matrix to cause a density gradient of particles.
2. The attenuating mass as claimed in claim 1 , wherein the epoxy resin matrix is adapted to have a glass transition temperature below 0° C.
3. The attenuating mass as claimed in claim 2 , wherein the epoxy resin matrix is adapted to have a viscosity at 25° C. of approximately 4000 to 9000 mPAS.
4. The attenuating mass as claimed in claim 3 , wherein the attenuating mass has a density increased by the filler to 1.5 to 4 g/cm 3 .
5. The attenuating mass as claimed in claim 4 , wherein the epoxy resin matrix has acidic functional groups.
6. The attenuating mass as claimed in claim 4 , wherein the epoxy resin matrix has ester groups.
7. An ultrasonic sensor, comprising:
an ultrasonic transmitter; and
an attenuating mass adapted to be soft and stable a temperature interval of −30′C to 150° C. and including an epoxy resin matrix and a filler with a multimodal grain size distribution, wherein the filler is dispersed throughout the resin matrix to cause a density gradient of particles.
8. The ultrasonic sensor as claimed in claim 7 , wherein the epoxy resin matrix is adapted to have a glass transition temperature below 0° C.
9. The ultrasonic sensor as claimed in claim 8 , wherein the epoxy resin matrix is adapted to have a viscosity at 25° C. of approximately 4000 to 9000 mPAS.
10. The ultrasonic sensor as claimed in claim 9 , wherein the attenuating mass has a density increased by the filler to 1.5 to 4 g/cm 3 .
11. The ultrasonic sensor as claimed in claim 10 , wherein the epoxy resin matrix has acidic functional groups.
12. The ultrasonic sensor as claimed in claim 10 , wherein the epoxy resin matrix has ester groups.