Rotating inertial pin blank stops for pressware die sets
In an apparatus for manufacturing pressware containers from container blanks there is provided a plurality of inertial blank stop pins disposed so as to position a container blank prior to press forming. The stop pins are rotatable in order to absorb the kinetic energy of the container blanks as they are fed to the apparatus and eliminate blank bounce. In a further aspect of the invention there is provided a method of forming plates utilizing the improved apparatus including the inertial blank stop pins.
1. A method of making a container from a container blank comprising positioning said blank on a lower die member configured to receive said blank said lower die member utilizing positioning means including an improved blank stop system comprising at least four rotatably mounted inertial blank stop pins disposed on the forward portion of the lower die member and projecting upwardly therefrom; at least two of said rotatably mounted inertial blank stop pins being outer pins located on said forward portion of said lower die member in opposing relationship to each other at a distance from each other which is less than the maximum transverse dimension of said container blank and which is greater than or equal to the maximum transverse dimension of the formed container, at least two of said rotatably mounted inertial blank stop pins being inner pins located on said forward portion of said lower die member, forwardly and inwardly located with respect to said outer pins, said inner pins being disposed in opposing relationship at a distance which is less than the maximum transverse dimension of the container formed from said container blank.
2. The method according to claim 1 , wherein said container blank has a caliper of from about 0.008 to about 0.050 inches.
3. The method according to claim 2 , wherein said container blank has a caliper of from about 0.012 inches to about 0.025 inches.
4. The method according to claim 2 , wherein said container blank has a moisture content of from about 8 to about 12 weight percent.
5. The method according to claim 4 , wherein said container blank has a moisture content from about 8.5 to about 10.5 weight percent.
6. The method according to claim 1 , wherein said outer pins project upwardly a greater distance than said inner pins.
7. The method according to claim 1 , wherein said outer and inner pins project upwardly at equal height from said lower die member.
8. The method according to claim 5 , wherein said outer pins project upwardly a distance of from about ½ to about 1½ of an inch and said inner pins project upwardly a distance from about ⅛ to about 1 inch.
9. The method according to claim 1 , wherein each of said pins is substantially cylindrical and is provided with an axial bore for receiving a retaining bolt.
10. The method according to claim 9 , wherein each of said pins has a counterbore cavity for receiving a bolt head.
11. The method according to claim 9 , wherein each of said pins has a diameter of from about ¼ to about 1 inch.
12. The method according to claim 10 , wherein each of said bolts has a diameter of from about ⅜ to about ¾ of an inch.
13. A method of making a container from a container blank comprising positioning said blank on a lower die member configured to receive said blank said lower die member utilizing positioning means including an improved blank stop system comprising at least four rotatably mounted inertial blank stop pins disposed on the forward portion of the lower die member and projecting upwardly therefrom:
at least two of said rotatably mounted inertial blank stop pins being outer pins located on said forward portion of said lower die member in opposing relationship to [each other] each other at a distance from each other which is less than the maximum transverse dimension of the formed container,
at least two of said rotatably mounted inertial blank stop pins being inner pins located on said forward portion of said lower die member, forwardly and inwardly located with respect to said outer pins, said inner pins being disposed in opposing relationship at a distance which is less than the maximum transverse dimension of the container formed from said container blank,
said rotatably mounted inertial blank stop pins farther being positioned, configured and dimensioned such that the stop pins will contact a blank at the forward portion of the die member as it is fed along the production direction and position the blank for forming as well as allow the formed product to slide between the outer pins and over the inner pins.