Inductor for transversal sealing, a packaging machine comprising the inductor for transversal sealing and a method thereof

Patent metadata

Field	Value
Publication number	US-12258168-B2
Application number	US-202118000528-A
Country	US
Kind code	B2
Filing date	Jun 16, 2021
Priority date	Jul 8, 2020
Publication date	Mar 25, 2025
Grant date	Mar 25, 2025

Abstract

An inductor for transverse sealing a packaging material tube filled with food product comprises a main body comprising first and second sealing surfaces facing the packaging material during a sealing state, a recess in the main body for receiving a knife during a cutting state, and an electric conductor arrangement, in the main body for inducing eddy currents in the packaging material during the sealing state. The first/second sealing surfaces each comprise a top section, an inner sealing section between the recess and the top section, and an outer sealing section between the top section and an outer edge of the inductor. The inner sealing section is inclined towards the recess, and the outer sealing section is inclined towards the outer edge, so that product in the tube is pushed away from a sealing band of the tube as the first/second sealing surfaces are pressed towards the sealing band.

First claim

The invention claimed is:

1. An inductor for transversal sealing of a tube of packaging material filled with food product, said inductor comprising:
a main body comprising a first and a second sealing surface arranged to face the packaging material during a sealing state,
a recess provided in the main body for receiving a knife during a cutting state, wherein the first and second sealing surface are on opposite sides of the recess, and
an electric conductor arrangement, provided in the main body, for inducing eddy currents in the packaging material during the sealing state,
each of the first and second sealing surfaces comprising a top section, an inner sealing section between the recess and the top section, and an outer sealing section between the top section and an outer edge of the inductor, and wherein the inner sealing section is continuously inclined with non-zero degrees inclination from the top section to the recess, and the outer sealing section is continuously inclined with non-zero degrees inclination from the top section to the outer edge, so that product in the food product held inside the tube is pushed away from a sealing band of the tube as the first and second sealing surfaces are pressed towards the sealing band.

2. The inductor according to claim 1 , wherein an outer sealing section length is larger than an inner sealing section length.

3. The inductor according to claim 1 , wherein an inner sub-section inclination of an inner sub-section of the outer sealing section is greater than an outer sub-section inclination of an outer sub-section of the outer sealing section, wherein the inner sub-section abuts the top section.

4. The inductor according to claim 1 , wherein the inner sealing section has constant inclination from the top section to the recess.

5. The inductor according to claim 1 , wherein a sealing band length is less than 14 mm.

6. The inductor according to claim 1 , wherein the electric conductor arrangement comprises a twin-loop.

7. A packaging machine for producing food packages, said packaging machine comprising:
a roll receiver arranged to receive a roll of packaging material,
a tube former arranged to form a tube from the packaging material,
a product filling device arranged to fill the tube with food product,
a transversal sealing arrangement arranged to provide transversal sealings in a lower portion of the tube, said transversal sealing arrangement comprising a first and a second sealing jaw element, wherein the first sealing jaw element is attached to a first arm and the second sealing jaw element is attached to a second arm, wherein the first arm is attached to a first motor arrangement and the second arm is attached to a second motor arrangement, wherein the first sealing jaw element comprises an inductor according to claim 1 ,
wherein the second sealing jaw element comprises an anvil,
wherein the first and second motor arrangement are configured to move the transversal sealing arrangement between
an upper, open state in which the first and second arms are in an upper position and the first and second sealing jaw elements are separated,
an upper, sealing state in which the first and second arms are in the upper position and the first and second sealing jaw elements are pressed onto the tube from opposite sides,
a lower, sealing state in which the first and second arms are in a lower position and the first and second sealing jaw elements are pressed onto the tube from the opposite sides,
a lower, open state in which the first and second arms are in the lower position and the first and second sealing jaw elements are separated,
wherein the inclined inner sealing section and the inclined outer sealing section of the inductor provides for that the food product is moved away from an inner and outer sealing section of the packaging material during an upper state transition from the upper, open state to the upper, sealing state.

8. The packaging machine according to claim 7 , wherein the food packages produced comprise less than 200 ml food product each.

9. The packaging machine according to claim 7 , wherein the packaging machine runs with a speed of less than 20,000 food packages per hour.

10. A method for producing food packages filled with food product, said method comprising:
receiving a roll of packaging material by using a roll receiver,
forming a tube from the packaging material by using a tube former,
filling the food product into the tube using a product filling device,
sealing the tube transversally in a lower portion of the tube by using a transversal sealing arrangement comprising a first and a second sealing jaw element, wherein the first sealing jaw element is attached to a first arm and the second sealing jaw element is attached to a second arm, wherein the first arm is attached to a first motor arrangement and the second arm is attached to a second motor arrangement, wherein the first sealing jaw element comprises an inductor for heating the packaging material,
wherein the inductor comprises:
a main body comprising a first and a second sealing surface arranged to face the packaging material during a sealing state,
a recess provided in the main body for receiving a knife during a cutting state, wherein the first and second sealing surface are on opposite sides of the recess, and
an electric conductor arrangement, provided in the main body, for inducing eddy currents in the packaging material during the sealing state,
wherein each of the first and second sealing surface comprises a top section, an inner sealing section between the recess and the top section, and an outer sealing section between the top section and an outer edge of the inductor,
wherein the inner sealing section is continuously inclined with non-zero degrees inclination from the top section to the recess, and the outer sealing section is continuously inclined with non-zero degrees inclination from the top section to the outer edge, the inner sealing section being inclined over a first inclination length, the outer sealing section being inclined over a second inclination length, the first inclination length being different from the second inclination length,
wherein the second sealing jaw element comprises an anvil,
wherein the step of sealing comprises the sub-steps of
placing the transversal sealing arrangement in an upper, open state in which the first and second arms are in an upper position and the first and second sealing jaw elements are separated by using the first and second motor arrangement,
placing the transversal sealing arrangement in an upper, sealing state in which the first and second arms are in the upper position and the first and second sealing jaw elements are pressed onto the tube from opposite sides by using the first and second motor arrangement, thereby providing for that particles in the food product held inside the tube are pushed away from a sealing band of the tube as the first and second sealing surfaces are pressed towards the sealing band,
placing the transversal sealing arrangement in a lower, sealing state in which the first and second arms are in a lower position and the first and second sealing jaw elements are pressed onto the tube from the opposite sides by using the first and second motor arrangement, and
placing the transversal sealing arrangement in a lower, open state in which the first and second arms are in the lower position and the first and second sealing jaw elements are separated by using the first and second motor arrangement.

11. The method according to claim 10 , wherein an outer sealing section length is larger than an inner sealing section length.

12. The method according to clai

Assignees

• Tetra Laval Holdings & Finance

Inventors

• Israelsson Karl
• Karlsson Per

Classifications

• B29C66/8491

  welding through a filled container, e.g. tube or bag · CPC title

• B65B9/12

  Subdividing filled tubes to form two or more packages by sealing or securing involving displacement of contents · CPC title

• B65B61/06

  by cutting · CPC title

• B65B51/227

  by induction welding · CPC title

• B65B9/2049

  Package shaping devices acting on filled tubes prior to sealing the filling opening (shaping or reshaping completed packages B65B61/24) · CPC title