Method of making aerosol valve mounting cups and resultant cups
Metal discs, preferably circular, are cut to a precise diameter and drawn to a preform with a channel and skirt for an aerosol valve mounting cup. The preform then undergoes further forming operations at stations in a press system. “Bumping” is carried out on the skirt edge at a station, to eliminate non-burr trimming of the cup edge, save material and obtain a carefully controlled skirt height and a substantially even skirt edge with minimized earring. The resultant cup terminating skirt edge is characterized by reformed metal. A further coaxing or pinch-cut operation may be performed on the cup skirt.
1. A method of manufacturing a mounting cup for an aerosol valve, said cup having an inner pedestal portion for mounting the aerosol valve, an outer circular channel portion for mounting on the bead of an aerosol container, and a skirt portion forming the outer wall of the channel portion with said skirt portion having a specified skirt height and a terminating edge, said method comprising:
cutting a metal blank from a metal sheet, said metal blank having a curved perimeter;
pressing and drawing said metal blank into a mounting cup preform in a preform pressing and drawing station, said mounting cup preform having a channel portion and a skirt portion having a skirt height and a terminating edge;
performing further forming operations on said mounting cup preform at a plurality of further stations to further form the mounting cup; and
performing a bumping operation on said terminating edge at one of said plurality of stations, said bumping operation comprising striking said terminating edge to reduce said skirt height to a specified dimension and to minimize any unevenness of said terminating edge.
2. The method of claim 1 , wherein said metal blank is a circular disc.
3. The method of claim 1 , wherein the method has a lack of any cutting operation to trim excess non-burr material from a perimeter of the mounting cup during its formation from said metal blank.
4. The method of claim 2 , wherein the method has a lack of any cutting operation to trim excess non-burr material from a perimeter of the mounting cup during its formation from said circular disc.
5. The method of claim 1 or claim 2 , wherein said metal blank is cut from said metal sheet at said preform pressing and drawing station.
6. The method of claim 1 or claim 2 , wherein said plurality of further stations include a sizing station, the method further comprising carrying out said bumping operation at said sizing station.
7. The method of claim 1 or claim 2 , wherein said plurality of further stations are a part of a belt fed or feed bar transfer press system.
8. The method of claim 1 or claim 2 , further including a coaxing station for moving a lower portion of said skirt portion slightly inward.
9. The method of claim 1 or claim 2 , further comprising a circular centering ring that extends into the outer circular channel portion of the cup during the bumping operation, said centering ring having a notch in an outside diameter with an upper notch wall, the method further comprising bumping said terminating edge with the upper notch wall just before bottoming said centering ring in the outer circular channel portion of the cup.
10. The method of claim 1 or claim 2 , further comprising a circular centering ring that extends into the outer circular channel portion of the cup during the bumping operation and has an adjacent bumping ring, the method further comprising bumping said terminating edge with said adjacent bumping ring just before bottoming the centering ring in the outer circular channel portion of the cup.
11. The method of claim 1 or claim 2 , wherein a circular centering ring extends into the outer circular channel portion of the cup during the bumping operation, the method further comprising clamping the outer circular channel portion between the centering ring and a lower support ring, and thereafter bumping said terminating edge with a separate bumping ring.
12. The method of claim 2 , wherein the metal disc has a diameter that is specified to permit the forming of the mounting cup with said skirt height of said specified dimension and without excess non-burr metal being present at a cup perimeter requiring a cutting operation to trim.
13. A method of manufacturing a mounting cup for an aerosol valve, comprising:
forming a metal blank having a curved perimeter;
forming said metal blank into a mounting cup preform, said mounting cup preform having a channel portion and a skirt portion having a skirt height and a terminating edge; and
striking said skirt portion terminating edge to reduce said skirt height to a specified dimension and to minimize unevenness of said skirt terminating edge.
14. The method of claim 13 , wherein the method has a lack of any cutting operation to trim excess non-burr material from a perimeter of the mounting cup during its formation from said metal blank.