Ultrasonic welding apparatus having plurality of sonotrodes

Patent metadata

Field	Value
Publication number	US-9427912-B2
Application number	US-201414782176-A
Country	US
Kind code	B2
Filing date	Apr 15, 2014
Priority date	Apr 25, 2013
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

The invention relates to an ultrasonic welding apparatus for ultrasonic machining of a material, having at least two sonotrodes and a converter device, which converts an electrical AC voltage into an ultrasonic vibration and sets the at least two sonotrodes in ultrasonic vibration, the at least two sonotrodes being arranged in such a manner that the material to be machined is arranged between them during machining and can at the same time be machined by the at least two sonotrodes. To specify an ultrasonic welding apparatus that allows effective material machining without an undesirable interaction occurring between the two sonotrodes, the converter device according to the invention excites the first sonotrode at a frequency f s1 and the second sonotrode at a frequency f s2 , f s2 being greater than f s1 .

First claim

The invention claimed is:

1. An ultrasonic welding apparatus for ultrasonic machining of a material comprising at least two sonotrodes ( 3 , 4 ) and a converter device ( 6 , 7 , 8 ) which converts an electrical AC voltage into an ultrasonic vibration and causes the at least two sonotrodes ( 3 , 4 ) to perform ultrasonic vibration, wherein the at least two sonotrodes ( 3 , 4 ) are so arranged that the material to be machined is disposed between them during the machining operation and can be machined at the same time by the at least two sonotrodes ( 3 , 4 ), wherein the converter device ( 6 , 7 , 8 ) excites the first sonotrode at a frequency f s1 and the second sonotrode at a frequency f s2 , wherein f s2 is greater than f s1 , characterised in that there is provided at least one third sonotrode ( 5 ), wherein the third sonotrode ( 5 ) is so arranged that the material to be machined is positioned between at least one sonotrode ( 3 ) on the one hand and at least two sonotrodes ( 4 , 5 ) on the other hand during the machining operation and wherein preferably the total surface area of the sonotrode ( 3 ) positioned on one side of the material to be machined approximately corresponds to the total surface area of the sonotrodes ( 4 , 5 ) positioned on the other side of the material to be machined.

2. An ultrasonic welding apparatus as set forth in claim 1 characterised in that f s2 is not an integral multiple of f s1 .

3. An ultrasonic welding apparatus as set forth in claim 1 characterised in that

f

S
⁢

⁢
2

-

f

S
⁢

⁢
1

f

S
⁢

⁢
1

≤
0.4

and preferably

f

S
⁢

⁢
2

-

f

S
⁢

⁢
1

f

S
⁢

⁢
1

≤

0.2
.

4. An ultrasonic welding apparatus as set forth in claim 1 characterised in that the at least two sonotrodes respectively have at least one flat sealing surface portion.

5. An ultrasonic welding apparatus as set forth in claim 1 characterised in that at least one sonotrode, preferably two sonotrodes, has at least one curved, preferably concavely curved sealing surface portion.

6. An ultrasonic welding apparatus as set forth in claim 5 characterized in that at least one sonotrode has two flat sealing surface portions and a curved sealing surface portion arranged between the two sealing surface portions.

7. An ultrasonic welding apparatus as set forth in claim 1 characterised in that the sonotrodes positioned on the same side of the material to be machined have mutually spaced sealing surfaces.

8. An ultrasonic welding apparatus as set forth in claim 2 characterised in that

f

S
⁢

⁢
2

-

f

S
⁢

⁢
1

f

S
⁢

⁢
1

≤
0.4

and preferably

f

S
⁢

⁢
2

-

f

S
⁢

⁢
1

f

S
⁢

⁢
1

≤

0.2
.

9. An ultrasonic welding apparatus as set forth in claim 2 characterised in that the at least two sonotrodes respectively have at least one flat sealing surface portion.

10. An ultrasonic welding apparatus as set forth in claim 3 characterised in that the at least two sonotrodes respectively have at least one flat sealing surface portion.

11. An ultrasonic welding apparatus as set forth in claim 1 characterised in that at least one sonotrode has at least one concavely curved sealing surface portion.

12. An ultrasonic welding apparatus as set forth in claim 1 characterised in that at least two sonotrodes each have at least one concavely curved sealing surface portion.

13. An ultrasonic welding apparatus as set forth in claim 2 characterised in that at least one sonotrode has at least one curved sealing surface portion.

14. An ultrasonic welding apparatus as set forth in claim 2 characterised in

Assignees

• Hermann Ultraschalltechnik Gmbh & Co Kg
• Herrmann Ultraschalltechnik Gmbh & Co Kg

Inventors

• Schneider Arnold
• Gnad Gerhard

Classifications

• B29C66/81423

  being concave · CPC title

• B29C66/81469

  one placed next to the other in a single line transverse to the feed direction, e.g. shoulder to shoulder sonotrodes · CPC title

• B29C66/9513

  characterised by specific vibration frequency values or ranges · CPC title

• B29C66/9512

  by controlling their vibration frequency · CPC title

• B29L2031/7128

  Bags, sacks, sachets (tea bags B29L2031/7122; medical bags B29L2031/7148) · CPC title