Adhesive bonding and miscellaneous chemical manufacture – Methods – Surface bonding and/or assembly therefor
Reexamination Certificate
1999-09-02
2002-04-02
Sells, James (Department: 1734)
Adhesive bonding and miscellaneous chemical manufacture
Methods
Surface bonding and/or assembly therefor
C156S204000, C156S210000, C156S227000, C156S269000, C156S470000, C156S498000, C156S499000
Reexamination Certificate
active
06364978
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a thermoplastic filter material, which has been heated for lying in folds and to an apparatus used therefor.
A filter material produced with the known method is known from German Utility Model 93 19 372. In the known filter material, cover layers are folded together with the filter material proper for ensuring that the folds are kept open also under pressure load by the medium flowing there through, i.e. that the folds do not collapse, whereby the passage resistance would be increased. Furthermore, the folds are held together by a cover layer which extends over the backs of the folds. However, during further processing, for instance for obtaining filter inserts, it is difficult to keep the folds of the filter material in such a close vicinity as is required for the filter material shown in
FIG. 1
of said utility model.
Thus it is the object of the present invention to provide a method of producing a folded filter material in which the folds are fixed in a constructional simple manner in close vicinity to each other.
SUMMARY OF THE INVENTION
The object is achieved by a method and apparatus in which the thermoplastic filter material which has been heated for forming the folds is accumulated in a cooling path such that said folds are pushed together and fixed by cooling with respect to their shape.
On the one hand, the spaces that are created by the thickness of the folding tools are eliminated between the folds thanks to the measure that the folds are pushed together following the heating operation and the laying in folds. On the other hand, these folds are fixed by cooling, so that it becomes much easier to pass the folds in a densely packed state to or through subsequent steps of the method.
Advantageous developments of the method according to the invention can be gathered from the following description:
REFERENCES:
patent: 4940500 (1990-07-01), Tadokoro et al.
patent: 5167740 (1992-12-01), Michaelis et al.
patent: 5804073 (1998-09-01), Ter Horst
patent: 5868889 (1999-02-01), Kahler
Skov Martin
Wandel Heinz
Moldex-Metric, Inc.
Schwartz Charles H.
Sells James
LandOfFree
Method and apparatus for producing a filter material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for producing a filter material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for producing a filter material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2928010