Antenna apparatus for transmitting data of a fill-level measuring device

Patent metadata

Field	Value
Publication number	US-9812781-B2
Application number	US-201314648962-A
Country	US
Kind code	B2
Filing date	Nov 26, 2013
Priority date	Dec 3, 2012
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

Antenna apparatus for transmitting data of a fill-level measuring device, comprising at least two coil arrangements (i=1, 2 . . . n). The coil arrangements i=1, 2 . . . n have a coil length (l i ) and a coil diameter (d i ), wherein the coil diameter (d i ) is less than the associated coil length (l i ). The coil arrangements (i=1, 2 . . . n) each intersect a straight line (e) in such a way that the straight line (e) and the longitudinal axis of the coil arrangements (i=1, 2 . . . n) form at the intersection an acute or 90° angle of intersection (g) of at least 85°, wherein the intersection of each coil arrangement (i=1, 2 . . . n) is arranged at a position between
3 7 ⁢ l i ⁢ ⁢ and ⁢ ⁢ 4 7 ⁢ l i ,
wherein the at least two coil arrangements (i=1, 2 . . . n) are arranged along this line (e) in a sequence, in the case of which the coil lengths l i of the coil arrangements (i=1, 2 . . . n) monotonically decrease l 1 >l 2 > . . . l n . The at least two coil arrangements (i=1, 2 . . . n), in each case, have a separation (s i ) along the line (e) between the coil arrangement (i) and (i+1), which is, at most, a fourth as large as the coil length (l i ).

First claim

The invention claimed is:

1. An antenna apparatus for transmitting data of a fill-level measuring device, comprising:
at least two coil arrangements, said coil arrangements have a coil length (l i ) and a coil diameter (d i ), wherein:
the coil diameter (d i ) is less than the associated coil length (l i );
said coil arrangements each intersect a straight line (e) in such a way that the straight line (e) and the longitudinal axis of said coil arrangements form at their intersection an angle of 90°;
the intersection of each coil arrangement is arranged at a position between

1
3

⁢

l
i

⁢

⁢
and
⁢

⁢

2
3

⁢

l
i

,

said at least two coil arrangements are arranged along this line (e) in a sequence, which the coil lengths l i of the coil arrangements monotonically decrease l 1 >l 2 > . . . l n ; and
said at least two coil arrangements, in each case, have a separation along the line (e) between the coil arrangement (i) and (i+1), which is, at most, exactly as large, as the coil length (l i ) of the longer coil, respectively.

2. The apparatus as claimed in claim 1 , wherein:
said coil arrangements have a curvature in the direction of a point on the line (e), which considered from the coil arrangement with the smallest coil length (l n ) lies on a side opposite the remaining coil arrangements.

3. The apparatus as claimed in claim 1 , wherein:
a periodic voltage is placed on said coil arrangements and the voltage of each coil arrangement has a phase difference relative to the two neighboring coil arrangements.

4. The apparatus as claimed in claim 3 , wherein:
said phase differences can be time varied.

5. The apparatus as claimed in claim 3 , wherein:
the voltages of uneven numbered and/or even numbered coil arrangements have the same phase φ 1 =φ 3 =φ 5 = . . . and/or φ 2 =φ 4 =φ 6 = . . . .

6. The apparatus as claimed in claim 3 , wherein:
said voltages comprise a digital signal.

7. The apparatus as claimed in claim 3 , wherein:
said voltages are sinusoidal and/or cosinusoidal.

8. The apparatus as claimed in claim 3 , wherein:
said voltages are sinusoidal and/or cosinusoidal and are triggered with a digital signal.

9. The apparatus as claimed in claim 8 , wherein:
said coil cores of said coil arrangements can be permanent magnets.

10. The apparatus as claimed in claim 3 , wherein:
said phase difference can be a half period.

11. The apparatus as claimed in claim 1 , wherein:
said coil lengths (l i ) from (i) to (i+1) are reduced by a length (Δl i ) between

2
10

⁢

l
i

⁢

⁢
and
⁢

⁢

4
10

⁢

l

i
+
1

=

l
i

-

Δ
⁢

⁢

l
i

.

12. The apparatus as claimed in claim 1 , wherein:
said coil lengths (l i ) from (i) to (i+1) are reduced by a length (Δl i ) between between

3
10

⁢

l
i

⁢

⁢
and
⁢

⁢

4
10

⁢

l
i

,

l

i
+
1

=

l
i

-

Δ
⁢

⁢

l
i

.

13. The apparatus as claimed in claim 1 , wherein:
said coil arrangements can have one or more coil cores.

14. The apparatus as claimed in claim 1 , wherein:
said coil lengths (l i ) from (i) to (i+1) are reduced by a length (Δl i ) between

1
10

⁢

l
i

⁢

⁢
and
⁢

⁢

5
10

⁢

l
i

.

15. The apparatus as claimed in claim 1 , wherein:
the intersection of each coil arrangement is arranged between ⅖ l i and ⅗ l i .

16. The apparatus as claimed in claim 1 , wherein:
the intersection of each coil arrangement is arranged between 3/7 l i and 4/7 l i .

Assignees

• Endress Hauser Gmbh Co Kg

Inventors

• Blodt Thomas

Classifications

• H01Q1/225 Primary

  used in level-measurement devices, e.g. for level gauge measurement · CPC title

• H01Q7/08

  Ferrite rod or like elongated core · CPC title

• H01Q7/06

  with core of ferromagnetic material (H01Q7/02 takes precedence) · CPC title

• H01Q7/00 Primary

  Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop · CPC title