Heat sealing apparatus

• US 4,792,373 A
• Filed: 06/18/1985
• Issued: 12/20/1988
• Est. Priority Date: 06/18/1985
• Status: Expired due to Fees

• Current Assignee: Dade International, Inc. (Siemens AG)
• Original Assignee: Baxter Travenol Laboratories Incorporated
• Inventors: Meguro, Jun-Ichi, Solberg, Arne L., Hsei, Paul K., Stark, William A.
• Primary Examiner(s): Ball, Michael W.
• Assistant Examiner(s): DAVIS, JENNA L
• Application Number:
  US06/746,232
• Time in Patent Office: 1,281 Days
• Field of Search: 156/228, 156/282, 156/292, 156/308.4, 156/497, 156/498, 156/581, 156/583.1, 156/583.4, 156/70, 156/219, 156/244.22, 156/275.1, 156/381, 156/379.8 , 156/380.8, 156/69, 53/555, 53/367, 493/191, 493/190
• US Class Current: 156/497
• CPC Class Codes: B29C 51/00 Shaping by thermoforming , i.e. shaping sheets or sheet like preforms after heating, e.g. shaping sheets in matched moulds or by deep-drawing; Apparatus therefor blow moulding of tubular preforms B29C49/00, deforming of tubular or hollow preforms B29C67/0014
• CPC Class Codes: B29C 51/267 Two sheets being thermoformed in separate mould parts and joined together while still in the mould B29C49/0691 takes precedence
• CPC Class Codes: B29C 65/18 using heated tools
• CPC Class Codes: B29C 65/7844 cooperating with specially formed features of at least one of the parts to be joined, e.g. cooperating with holes or ribs of at least one of the parts to be joined parts to be joined comprising holes or slots for the purpose of positioning said parts B29C65/7808; parts to be joined comprising inter-cooperating positioning features B29C65/7814; welding using friction, the welding tool cooperating with specially formed features of at least one of the parts to be joined, e.g. cooperating with holes or ribs of at least one of the parts to be joined B29C65/069
• CPC Class Codes: B29C 66/003 Protecting areas of the parts to be joined from overheating B29C66/348, B29C66/8744 take precedence
• CPC Class Codes: B29C 66/1312 Single flange to flange joints, the parts to be joined being rigid the parts to be joined being flexible B29C66/133
• CPC Class Codes: B29C 66/133 Fin-type joints, the parts to be joined being flexible the parts to be joined being rigid B29C66/1312
• CPC Class Codes: B29C 66/54 Joining several hollow-preforms, e.g. half-shells, to form hollow articles, e.g. for making balls, containers; Joining several hollow-preforms, e.g. half-cylinders, to form tubular articles
• CPC Class Codes: B29C 66/80 General aspects of machine operations or constructions and parts thereof
• CPC Class Codes: B29C 66/81427 comprising a single ridge, e.g. for making a weakening line; comprising a single tooth
• CPC Class Codes: B29C 66/81431 comprising a single cavity, e.g. a groove
• CPC Class Codes: B29C 66/81811 of the welding jaws
• CPC Class Codes: B29C 66/83221 cooperating reciprocating tools, each tool reciprocating along one axis
• CPC Class Codes: B29L 2031/40 Test specimens ; Models, e.g. model cars mannequins B29L2031/7028; Probes
• CPC Class Codes: B29L 2031/753 Medical equipment; Accessories therefor bloodbags, medical bags B29L2031/7148; artificial eyes B29L2011/0008

Abstract

A system for heat sealing in conjunction a pair of plastic strips each of having a series of regularly spaced transverse pockets so that the pockets together form chambers separated by webs. The two pocketed strips to be joined are brought together and the strips heat sealed around the pockets to seal the chambers from one another while passing cooling fluid over the pockets so as to avoid distortion or collapse of the pockets.

Claims

1. Apparatus for heat sealing in conjunction a pair of plastic strips each having a series of regularly spaced transverse pockets separated by web portions so that the pockets together form chambers, and in which the web portion of each strip extends along at least one longitudinal side edge and is formed therealong with a row of indexing perforations, comprising:

first and second coacting heat sealing dies each having heating surfaces for heat sealing the strips together intermediate the pockets,

series of openings in each of said dies, each opening being adapted to receive one of said pockets with said pocket spaced therewithin, said heating surfaces extending at least partially around each of said openings so as to operate to seal the chambers, formed by the association of the strips, from one another,

means for engaging said web portions of said strips for aligning said strips with respect to one another and with respect to said openings, and

means for introducing cooling fluid into said openings so that it flows over the surfaces of said pockets for cooling said pockets received therein during heat sealing,

said dies including heating surfaces separate from the heating surfaces extending around said openings for sealing around said perforations,

at least one of said heat sealing dies having at least one locator pin means which enters an indexing perforation in the web of each said strip to align said strips with respect to each other and with respect to said openings.

2. Heat sealing apparatus as defined in claim 1 in which said locator pin means is a heat pipe which remains cool despite the surrounding high temperature of the heat sealer die.

3. Apparatus for heat sealing in conjunction a pair of plastic strips each formed with a series of regularly spaced transverse pockets separated by web portions to form two integral mirror image side-by-side cuvette belts, comprising:

first and second coacting heat sealing dies each having heating surfaces for sealing the strips together extending around openings adapted to receive said pockets with one said pocket in each opening and each said pocket spaced within the respective opening,

means for engaging said web portions of said strips for aligning said strips with respect to one another and with respect to said openings, and

means for introducing cooling fluid into said openings so that it flows over the surfaces of said pockets for cooling the pockets received therein during heat sealing,

said openings being defined by cavities in said dies and there being provided in the base of each cavity, a central entry aperture for the introduction of cooling fluid and exit apertures adjacent each end for the outflow of the cooling fluid.

4. Apparatus for heat sealing in conjunction a pair of plastic strips each formed with a series of regularly spaced transverse pockets separated by web portions to form two integral mirror image side-by-side cuvette belts, in which the web portions are formed along each longitudinal edge with a row of indexing perforations, said apparatus comprising:

first and second coacting heat sealing dies each having heating surfaces for sealing the strips together extending around openings adapted to receive said pockets with one said pocket in each opening and each said pocket spaced within the respective opening,

means for engaging said web portions of said strips for aligning said strips with respect to one another and with respect to said openings, and

means for introducing cooling fluid into said openings so that it flows over the surfaces of said pockets for cooling the pockets received therein during heat sealing,

said sealing dies including heating surfaces for sealing around said perforations, and said aligning means including a plurality of locator pins which each enter an indexing perforation in the web portion of each strip.

5. Heat sealing apparatus as defined in claim 4 in which said heating surfaces for sealing around said perforations are discrete narrow surfaces separate from one another.

6. Heat sealing apparatus as defined in claim 4 including a narrow longitudinal heating surface along each side of each die for sealing the strips along each edge outbound of the perforations.

7. Heat sealing apparatus as defined in claim 6, in which said heating surfaces for sealing said perforations are discrete narrow surfaces separate from one another and said narrow longitudinal heating surfaces are each integral with the associated heating surfaces for sealing around said perforations