Mold for plastic needlepoint sheet

• US 4,362,290 A
• Filed: 07/17/1981
• Issued: 12/07/1982
• Est. Priority Date: 07/17/1981
• Status: Expired due to Term

• Current Assignee: Westminster Marketing Incorporated
• Original Assignee: Westminster Marketing Incorporated
• Inventors: Musante, Louis P., Marx, Michael K.
• Primary Examiner(s): Flint, Jr., J. Howard
• Application Number:
  US06/283,908
• Time in Patent Office: 508 Days
• Field of Search: 425/DIG. 42, 425/588, 425/542, 425/394, 425/395, 249/60, 249/68, 249/67
• US Class Current: 249/60
• CPC Class Codes: B29C 33/00 Moulds or cores; Details thereof or accessories therefor
• CPC Class Codes: B29C 45/26 Moulds
• CPC Class Codes: B29D 28/00 Producing nets or the like, e.g. meshes, latticesby knotting D04G

Abstract

An injection mold for molding plastic needlepoint sheets which have a plurality of aligned rows of perforations which define plastic threads therebetween in a lattice configuration. The mold has engageable top and bottom mold body halves with open uniform mold channels formed in each half in a lattice configuration wherein the channel lattices of the mold halves cooperatively mate with each other upon engagement to define a mold cavity therebetween for the molding of a needlepoint sheet. The lattice channels in the mold body halves are constructed whereby the lattice channels in one half define a greater total volume than that of the other half, such that the greater volume of plastic to be molded in the mold cavity is received in the ejection half of the mold. In order to facilitate removal of the molded sheet from the mold, the lattice mold channels in the mold body halves are contoured to define a resultant cross section of the thread of a needlepoint sheet to be molded which is polygonal. In order to compensate for possible misalignment or offset of the mold halves during the molding operation, the cross-sectional opening width of the lattice mold channels in one mold half are greater than that of the other mold half to provide an intentional mating mismatch between the mold channel openings of the respective mold halves.

Claims

1. In a mold having engageable top and bottom mold body halves with open uniform mold channels formed in each half in a lattice configuration wherein the channel lattices of the mold halves cooperatively mate with each other upon engagement of said mold halves to define a mold cavity therebetween for molding therein of a resultant needlepoint sheet of flexible plastic material having a plurality of aligned rows of perforations with said perforations defining plastic threads therebetween, the improvement comprising said open lattice channels in said mold body halves constructed whereby the lattice channels in one half define a greater total volume than that of the other half, such that the greater volume of plastic to be molded in said cavity is received in said one mold half.

2. The mold of claim 1, including ejection pin means in said one mold body half for ejecting a molded plastic needlepoint sheet from said lattice mold channels in said one mold body half after said mold body halves have been separated.

3. The mold of claim 1, wherein said lattice mold channels in said mold body halves are contoured to define a resultant cross section of the threads of a needlepoint sheet to be molded in said cavity which is polygonal.

4. The mold of claim 3, wherein said polygonal cross section is ten sided.

5. The mold of claim 1 or 3, wherein the cross-sectional opening width of the lattice mold channels in one mold half are greater than that of the other mold half to provide an intentional mating mismatch between the channel openings of the respective mold halves.

6. In a mold having engageable top and bottom mold body halves with open uniform mold channels formed in each half in a lattice configuration wherein the channel lattices of the mold halves cooperatively mate with each other upon engagement of said mold halves to define a mold cavity therebetween for molding therein of a resultant needlepoint sheet of flexible plastic material having a plurality of aligned rows of perforations with said perforations defining plastic threads therebetween, the improvement comprising said lattice mold channels in said mold body halves contoured to define a resultant cross section of the threads of a needlepoint sheet to be molded in said cavity which is polygonal.

7. The mold of claim 6, wherein said polygonal cross section is ten sided.

8. The mold of claim 6 or 7, wherein the cross-sectional opening width of the lattice mold channels in one mold half are greater than that of the other mold half to provide an intentional mating mismatch between the channel openings of the respective mold halves.

9. In a mold having engageable top and bottom mold body halves with open uniform mold channels formed in each half in a lattice configuration wherein the channel lattices of the mold halves cooperatively mate with each other upon engagement of said mold halves to define a mold cavity therebetween for molding therein of a resultant needlepoint sheet of flexible plastic material having a plurality of aligned rows of perforations with said perforations defining plastic threads therebetween, the improvement comprising the cross-sectional opening width of the lattice mold channels in one mold half are greater than that of the other mold half to provide an intentional mating mismatch between the channel openings of the respective mold halves.