Reusable silicone vacuum bag/tool flange sealing method

Abstract

An improvement to a process for making plastic parts in infusion processes using a reusable polymer soft flexible bag, wherein the bag is sealed directly to the tool flange portion using an interlocking press sealing device. The interlocking device has one mating portion bonded to the tool flange and the other mating portion either bonded to the bag or integrally assimilated into the bag during its manufacture by spraying or swirl spraying one or more multiple layers or coats of a polymer made from one or plural component polymer material, such as that described in U.S. Pat. No. 7,014,809 dated Mar. 21, 2006. Alternative seals include seals made from material suitable for providing a breathable seal against composite materials allow for the passage of air through or underneath a resultant seal during the infusion process. Seals can also be used between soft bags.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 a is a conceptual depiction of the invention where an example of the closure means depicted is the use of V-shaped seals bonded to the soft bag;

FIG. 1 b is a conceptual depiction of the present invention depicting a combination of a V-shaped seal with a press and seal channel type of seal as an alternative to FIG. 1a;

FIG. 1 c is a conceptual depiction of the present invention depicting a combination of a concentric inner seal used with a laminate schedule and an optional offset between the bag and the contact tool as well as an outer perimeter seal; and

FIG. 2 is a conceptual depiction of the a plurality of smaller soft bags being used with a plurality of other soft bags (upper bag) with an example of a press and seal channel type of seal being used between the bags.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, FIGS. 1a-1c and 2 disclose a conceptual depiction of the present invention, which is a re-usable silicone vacuum bag/tool flange sealing method or smaller bag to smaller bag sealing method to create a larger bag, and is depicted generally as 10.

In one embodiment of the invention, the inventive method is used with a reusable silicone vacuum bag 16 and a hard tool 12 to make a plastic part (not shown). More particularly, the invention comprises closure means 20 between the flange 14 of the hard tool 12 and the vacuum bag 16 for sealing a perimeter of the vacuum bag 16 to the flange tool 12 before initiating an infusion process.

In the embodiment using a press and seal channel type of closure means, a first mating portion 20a of the closure means 20 is attached to the tool flange 14 and is engagable with a corresponding second mating portion 20b of the closure means 20, which in turn is attached to the vacuum bag 16. The closure means 20 is re-sealable for multiple uses. This type of press and seal closure means is preferably used as the outer perimeter seal as shown in FIG. 1b or FIG. 1c. The second mating portion 20b of the closure means 20 attached to the vacuum bag 16 is adhesively bonded to the vacuum bag 16.

When the vacuum bag 16 is made by spraying or swirl spraying one or more coats of a polymer material made from one or plural component polymer on a surface of an opposing mold serving as a pattern from which the formed bag 16 is configured in accordance with the process described in U.S. Pat. No. 7,014,809, successive coats of the sprayable polymer material are applied once a previously applied coat becomes sufficiently tack-free so as to not cause tearing of the previously applied coat during the spraying of the successive coat. Resin inlet ports 18a and vacuum ports 18b are inserted where desired, and the sprayed polymer material is cured when a desired number of the one or more coats of the polymer material are applied thereby forming the soft reusable flexible bag 16, which is then used in conjunction with a more rigid mold or other manufacturing aid to make a desired part.

When the bag 16 is made using the above described spraying process, the second mating portion 20b of the closure means 20 along the perimeter portion of the vacuum bag 16 may be inserted during the spraying process, wherein the second mating portion 20b is thereby integrated, molded or modeled into the vacuum bag 16.

Typically, an inner seal 22 is also used in the process and although FIGS. 1a-1b depict this seal as a V-shaped profile seal as described in the summary of the invention above and FIG. 1c depicts this seal 22 as a relatively square profile. The inner seal 22 will not be of the tongue and groove configuration. The inner seal 22 will still be bonded molded or modeled to the underside of the bag 16, but in this case, the inner seal 22 will seal against the contact mold flange 14 or a laminate schedule or other media 24 within or against the contact mold 12 and flange 14, yet will allow for passage of air or resin or both between the seal into the area of greatest vacuum. This inner seal 22 can be bonded, molded, or modeled to complete its attachment to the bag. FIG. 1a depicts the use of the V-shaped seal 22 in both the outer perimeter position as well as inward of the vacuum ports 18b. Further, as depicted in FIG. 1b, the vacuum port 18b may alternatively be located on the flange 14 (Vacuum port 18b is shown in phantom in this case).

The closure means 20 between the flange 14 of the hard tool 12 and the vacuum bag 16 for sealing the perimeter portion of the vacuum bag 16 to the flange tool 12 before initiating the infusion process comprises, in one preferred embodiment, a tongue and groove press sealing connection or as mentioned above, also called a press and seal channel type of seal system between the hard tool flange 14 and the soft bag 16. This type of connection is well known in the food container or food bag industry.

The drawings are intended to show merely examples of inner and outer seal configurations. The inventive process comprises the use of seals attached to the soft bag where the inner seal engage with the components in the contact tool 14 to provide a seal as discussed above.

When desired or needed, an stand-offs or offsets 26, which are typically molded, modeled or adhesively bonded, may be optionally added between the inner and outer seal 22,20 to facilitate vacuum movement throughout the area between the seals.

FIG. 2 conceptually depicts the use of a plurality of channel types of seals or closure means 20 attached to a bag 16 for use with other soft bags 16 to make smaller components of a larger product to be made or to make a larger bag for such applications as a hull of a boat.

It should be understood that the preceding is merely a detailed description of one or more embodiments of this invention and that numerous changes to the disclosed embodiments can be made in accordance with the disclosure herein without departing from the spirit and scope of the invention. The preceding description, therefore, is not meant to limit the scope of the invention. Rather, the scope of the invention is to be determined only by the appended claims and their equivalents.

Claims

1. A reusable polymer vacuum bag/tool flange sealing method for use in infusion or vacuum bag processes to be used in the manufacturing of plastic parts comprising: providing a reusable polymer vacuum bag and a hard tool to make a plastic part;providing a vacuum port in the reusable polymer vacuum bag or in a flange of the hard tool; andproviding spaced-apart outer and inner closure means between a flange of the hard tool and the vacuum bag for sealing an outer perimeter portion of the vacuum bag to the flange tool and having the inner closure means pressing against the flange tool or against a laminate schedule in the tool before initiating a vacuum process, the vacuum port being located between said outer and inner closure means;wherein the outer closure means is molded, modeled or adhesively bonded to the vacuum bag and is further made from material suitable for providing an airtight seal against the flange of the hard tool during the process,wherein the inner closure means is molded, modeled or adhesively bonded to the vacuum bag and is further adapted to allow for a sufficient vacuum, resin or both to be pulled beneath the inner closure means's seal against the hard tool flange or schedule and as such would allow and facilitate the drawing of air or a resinous product between said vacuum bag and said hard tool during the infusion process, andwherein said outer and inner closure means are capable of multiple uses.

2. The method according to claim 1, wherein the polymer vacuum bag is made by spraying or swirl spraying one or more coats of a polymer material made from one or plural component polymer on a surface of an opposing mold serving as a pattern from which the formed bag is configured, wherein successive coats of the sprayable silicone material are applied once a previously applied coat becomes sufficiently tack-free so as to not cause tearing of the previously applied coat during the spraying of the successive coat, inserting of resin ports and vacuum ports where desired; and curing said sprayed silicone material when a desired number of the one or more coats of the silicone material are applied; wherein the cured formed soft reusable flexible polymer vacuum bag is configured so as to be used in conjunction with a more rigid mold or other manufacturing aid to make a desired part.

3. The method according to claim 2, wherein said closure means is integrated into said polymer vacuum bag during the spraying process.

4. The method according to claim 1, wherein the outer closure means between the flange of the hard tool and the polymer vacuum bag comprises a tongue and groove press sealing connection, wherein a bottom mating half of said tongue and groove press sealing connection is bonded to the flange or a single part seal configured and capable of creating an adequate outer seal wherein said single part outer seal is modeled molded or adhesively bonded to the polymer vacuum bag yet lies between the hard tool flange and the polymer vacuum bag.

5. The method according to claim 1, wherein the inner and outer closure means comprises a seal configured with a desired profile.

6. The method according to claim 1, further comprising: providing offset means between the polymer vacuum bag and the flange of the hard tool, said offset means being located between the spaced-apart outer and inner closure means.

7. A reusable polymer vacuum bag sealing method for use in infusion or vacuum bag processes to be used in the manufacturing of various size plastic parts comprising: providing a plurality of soft bag segments, wherein each soft bag segment overlaps an adjacent soft bag segment to form an overlap portion;providing closure means between adjacent soft bag segments at the overlap portion, wherein respective mating portions of the closure means are molded, modeled or adhesively bonded to respective sides of the soft bag segments to be joined; and joining orinstalling the plurality of soft bag segments for the creation of a larger unified bag for use in allowing the creation of a vacuum to be used in making the desired plastic part using an infusion or vacuum bag process,wherein said closure means are capable of multiple uses.

8. The method according to claim 7, wherein the closure means between each of the plurality of soft bag segments comprises a tongue and groove press sealing connection.