US 4,625,498 AGranted

Apparatus for applying recessed membrane seals to containers

AssigneeSealright Co., Inc.

InventorJack D. Parsons

Life of this patent

Estimating the term…

Loading patent…

Abstract

A method and apparatus for applying and sealing recessed membranes to containers in a single operation. The membranes are partially cut from a continuous flexible web of film material and remain on the web due to thin necks of film material that are left after the cutting operation. An applicator head is carried on a power cylinder and acts to detach the membranes from the web, to apply the membranes to the containers at recessed locations, and to heat seal the marginal portions of the membranes to the container rims. The applicator head includes a vacuum head which attracts the membranes by suction and a sealing head which heat seals the membranes to the containers. The vacuum head has a tapered vacuum surface which properly centers the membranes and assists in expelling air from the containers before the heat seal is effected. The vacuum head is spaced from the heated sealing head to minimize the heat transfer and may be additionally cooled by a fluid cooling system.

Claims18

Dependent claims

Apparatus for applying a flat flexible membrane to a container having a rim, said apparatus comprising:

a frame;
an applicator head for applying the membrane to the container, said applicator head having a vacuum surface for applying suction to the membrane and a sealing surface for sealing a marginal portion of the membrane to the rim of the container, said vacuum surface and sealing surface being rigidly connected to one another in the applicator head;
means for mounting said applicator head on the frame for generally up and down movement between a raised position wherein the applicator head is located above the container and a lowered position wherein said vacuum surface is lowered into the container a predetermined distance below the rim and said sealing surface is on the rim of the container;
means for applying suction to said vacuum surface;
means for maintaining a flat web of material under tension with the membrane carried on the web and located between the container and applicator head in the raised position of the latter;
power means for effecting movement of said applicator head from the raised position to be lowered position to effect adherence of the membrane to said vacuum surface by suction and detachment of the membrane from the web as said vacuum surface moves below the web and into the container, said vacuum surface projecting beyond said sealing surface to deform and recess the membrane said predetermined distance below the rim of the container before a marginal portion of the membrane is engaged against the rim of the container by said sealing surface;
and
means for heating said sealing surface to heat seal the marginal portion of the membrane to the rim of the container with the membrane recessed below the rim.

5 more elements

Apparatus for applying to a container rim a flexible membrane carried to a position aligned above the container on a continuous flat web of flexible material which is non-ductile and unable to sustain a preformed shape, said apparatus comprising:

an applicator head having a vacuum head for applying suction to the membrane and a sealing head for heat sealing a marginal portion of the membrane to the container rim, said vacuum head having a vacuum surface and said sealing head having a sealing surface;
means for rigidly connecting said vacuum head to said sealing head with an air space therebetween to inhibit heat transmission and with said sealing surface generally surrounding said vacuum surface and spaced above same by a predetermined distance;
means for applying suction to said vacuum surface to effect adherence of the membrane thereto;
means for applying heat to said sealing head and sealing surface to effect heat sealing of the marginal portion of the membrane to the container rim when said marginal portion is pressed against the rim by said sealing surface;
and
power means for moving the applicator head from a raised position above the web to a lowered position below the web to effect adherence of the membrane to the vacuum surface by suction and detachment of the membrane from the web, said sealing surface pressing and heat sealing the marginal portion of the membrane against the rim in the lowered position and said vacuum head entering the container in the lowered position to recess the membrane below the container rim by said predetermined distance before said sealing surface presses said marginal portion against the rim.

3 more elements

Dependencies are inferred from the claim text.