Tray sealer

Patent metadata

Field	Value
Publication number	US-10913562-B2
Application number	US-201715832685-A
Country	US
Kind code	B2
Filing date	Dec 5, 2017
Priority date	Dec 6, 2016
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A tray sealer including a sealing station comprising a tool upper part, a clamping frame and a tool lower part. The tool upper part may surround a dome-shaped die used for deforming a skinnable top film. First and second channels in the dome-shaped die and in the tool upper part, respectively, are connectable to one another. The tool upper part or the dome-shaped die may comprise at least a third channel communicating with a vacuum generator so as to generate a thermal air convection from the first channel to the third channel along a side of the top film facing the dome-shaped die.

First claim

What is claimed is:

1. A method of operating a tray sealer, the method comprising the steps of:
providing a tray sealer that includes a control unit and a sealing station, the sealing station comprising a tool upper part, a clamping frame and a tool lower part;
receiving a dome-shaped die in the tool upper part;
deforming a skinnable top film using the dome-shaped die, wherein the dome-shaped die comprises at least a first channel that is in fluid communication with a second channel in the tool upper part, wherein the dome-shaped die has an inner contact surface that defines a cavity;
clamping the top film in position on the tool upper part in a gas-tight manner using the clamping frame to define a chamber within the tool upper part;
withdrawing air from the chamber out of at least a third channel defined in the tool upper part and in fluid communication with the chamber using a vacuum generator that is in fluid communication with the third channel;
introducing a volume of air into the cavity through the first channel of the dome-shaped die and the second channel of the tool upper part using the vacuum generator;
heating the volume of air introduced into the cavity using the dome-shaped die prior to the volume of air being introduced into the cavity; and
generating a thermal air flow along a side of the top film facing the dome-shaped die so that heat from the heated air will be given off to the top film while the heated air passes by the top film, wherein the introducing the volume of air into the cavity through the first channel of the dome-shaped die occurs simultaneously with the withdrawing air from the chamber out of at least the third channel step; and
wherein the generating the thermal air flow along the side of the top film facing the dome-shape die further comprises the thermal air flow being introduced in the cavity, passing between the film and at least one lower edge of the dome-shaped die, through a gap defined between the tool upper part and the dome-shaped die, and out of the chamber through the third channel.

2. The method according to claim 1 , wherein the generating the thermal air flow comprises providing an air flow having a pulse-like nature by clocking the operation of a third valve disposed between the dome-shaped die and the vacuum generator, in a defined series of time intervals.

3. The method according to claim 2 , wherein the defined series of time intervals is a cycle time in a range between 0.1 seconds and 0.5 seconds.

4. The method according to claim 1 , further comprising supplying ambient air to the dome-shaped die using a blowing device.

5. The method according to claim 1 , further comprising supplying heated air to the dome-shaped die using a heating device provided outside the dome-shaped die in addition to the heating the volume of air introduced into the cavity using the dome-shaped die.

6. The method according to claim 1 , further comprising a step of regulating a flow of air into or out of the cavity using a second valve on the second channel, the second valve being selectively moveable between a first position and a second position, wherein in the first position, the cavity is in fluid communication with the vacuum generator, and in the second position, the cavity is in fluid communication wither an opening to a surrounding environment.

7. The method according to claim 1 , further comprising a step of preventing contact between the film and a sealing surface of the dome-shaped die during the generating the thermal air flow along the side of the top film using a plurality of side channels disposed through the dome shaped die between the inner contact surface and an outer side of the dome-shaped die that faces away from the inner contact.

8. A method of operating a tray sealer, the method comprising the steps of:
providing a tray sealer that includes a control unit and a sealing station, the sealing station comprising a tool upper part, a clamping frame and a tool lower part;
receiving a dome-shaped die in the tool upper part;
deforming a top film using the dome-shaped die, wherein the dome-shaped die comprises at least a first channel that is in fluid communication with a second channel in the tool upper part, and wherein the dome-shaped die has an inner contact surface that defines a cavity;
clamping the top film in position on the tool upper part in a gas-tight manner using the clamping frame to define a chamber within the tool upper part;
introducing a first volume of air into the cavity, wherein the introduced first volume air enters the cavity through the second channel of the tool upper part and the first channel of the dome-shaped die;
heating the first volume of air introduced into the cavity using the dome-shaped die prior to the introducing the first volume of air into the cavity so that the heated first volume of air will heat the top film as the heated air contacts the top film; and
generating a thermal air flow along a side of the top film facing the cavity of the dome-shaped die by withdrawing a second volume of air from the chamber through a third channel defined in the tool upper part and in fluid communication with the chamber and and a vacuum generator using the vacuum generator simultaneously with the introducing the first volume of air into the chamber, wherein the first volume of air enters the cavity through the first channel and the second volume of air exits the cavity, passes between the film and at least one lower edge of the dome-shaped die, through a gap defined between the tool upper part and the dome-shaped die and out of the chamber through at least the third channel.

Assignees

• Multivac Haggenmueller Kg

Inventors

• Gabler Albert
• Mader Andreas
• Zedelmaier Thomas
• Capriotti Luciano

Classifications

• B65B47/02

  with means for heating the material prior to forming · CPC title

• B65B31/02

  Filling, closing, or filling and closing, containers {or wrappers} in chambers maintained under vacuum or superatmospheric pressure or containing a special atmosphere, e.g. of inert gas · CPC title

• B65B31/04

  Evacuating, pressurising or gasifying filled containers or wrappers by means of nozzles through which air or other gas, e.g. an inert gas, is withdrawn or supplied · CPC title

• B65B11/52

  one sheet being rendered plastic, e.g. by heating, and forced by fluid pressure, e.g. vacuum, into engagement with the other sheet and contents, e.g. skin- {, blister-, or bubble-} packaging · CPC title

• B65B7/164

  Securing by heat-sealing · CPC title