Metallised plastic antenna funnel for a fill level radar
A metalized plastic antenna includes a plastic antenna body with metallization on the inside. In this arrangement metallization is used for conducting electromagnetic waves. Furthermore, metallization may be implemented as a protective coating so that chemical resistance of the plastic antenna may be ensured even in the case of corrosive environmental conditions.
1. A metallised plastic antenna for a fill level radar, comprising:
an antenna body made of a plastic material; and
a collar having a connection region,
wherein an inside of the antenna body includes metallisation adapted for conducting electromagnetic waves, and
wherein the connection region of the collar includes a first angle in relation to the longitudinal axis of the collar such that the connection region can be placed against a waveguide so as to provide a seal.
2. The metallised plastic antenna according to claim 1 , wherein the inside of the antenna body forms a hollow space; wherein the hollow space comprises an aperture; and wherein the hollow space is filled at least in part with a filler that closes off the aperture of the hollow space.
3. The metallised plastic antenna according to claim 1 , wherein the filler comprises a dielectric material.
4. The metallised plastic antenna according to claim 1 , wherein the frequency of the electromagnetic waves is between 50 gigahertz and 100 gigahertz.
5. The metallised plastic antenna according to claim 1 , wherein the frequency of the electromagnetic waves is between 75 gigahertz and 85 gigahertz.
6. The metallised plastic antenna according to claim 1 , wherein the frequency of the electromagnetic waves is between 5 gigahertz and 30 gigahertz.
7. The metallised plastic antenna according to claim 1 , wherein the plastic antenna is designed as one of a horn antenna and as a parabolic antenna.
8. The metallised plastic antenna according to claim 1 , wherein the antenna body comprises glass-fibre reinforced plastic.
9. The metallised plastic antenna according to claim 1 , wherein the antenna body comprises polybutylene therapthalate and glass fibre.
10. The metallised plastic antenna according to claim 8 , wherein the glass fibre content in the antenna body is between 25% and 35%.
11. The metallised plastic antenna according to claim 1 , wherein metallisation of the inside of the antenna body comprises a varnish coating that has been enriched with conductive elements.
12. The metallised plastic antenna according to claim 11 , wherein the varnish coating comprises a metal-filled conductive varnish.
13. The metallised plastic antenna according to any one of the preceding claims, wherein metallisation of the inside of the antenna body has been applied as a high vacuum vapour-deposit layer.
14. The metallised plastic antenna according to claim 1 , wherein metallisation of the inside of the antenna body has been applied as a chemical electroplating layer.
15. The metallised plastic antenna according to claim 1 , further comprising: an encapsulation for closing off the aperture of the hollow space; wherein the encapsulation serves to provide chemical protection to the inside of the antenna body from external influences.
16. The metallised plastic antenna according to claim 15 , wherein encapsulation is designed as a lens for focussing the electromagnetic waves.
17. The metallised plastic antenna according to claim 1 , wherein the connection region of the plastic antenna is rotationally symmetrical in relation to the longitudinal axis of the collar.
18. The metallised plastic antenna according to claim 1 , further comprising a second layer; wherein the second layer is arranged between the metallisation and the antenna body.
19. The metallised plastic antenna according to claim 1 , further comprising a third layer; wherein the third layer is arranged on the metallisation.
20. A fill level radar for determining the fill level in a tank, comprising:
a plastic antenna according to claim 1 for at least one of transmitting receiving electromagnetic waves; and
a waveguide feeding the electromagnetic waves to the antenna,
wherein the waveguide includes a region for connecting the waveguide to the connection region of the plastic antenna;
wherein the region of the waveguide in the connected state includes a second angle in relation to the longitudinal axis of the collar of the plastic antenna;
wherein the connection region of the plastic antenna includes a first angle in relation to the longitudinal axis of the collar of the lastic antenna which first angle is larger than the second angle; and
wherein the connection region of the plastic antenna can be placed against the region of the waveguide so as to provide a seal.
21. The use of a plastic antenna according to claim 1 for fill level measuring.
22. A method for producing a plastic antenna according to claim 1 , comprising the steps of: providing an antenna body from a plastic, with an inside; metallisation of the inside of the antenna body for conducting electromagnetic waves.
23. The method according to claim 22 , further comprising the step of: plasma activation of the inside prior to metallisation; wherein metallisation involves a step selected from the group comprising varnish coating, high-vacuum vapour depositing, and chemical electroplating.
24. The method according to claim 22 , further comprising the step of: applying a second layer to the inside of the antenna body prior to metallisation.
25. The method according to claim 22 , further comprising the step of: applying a third layer to the metallisation of the antenna body.