Compression molding machine
View Patent ↗A compression molding machine includes a wheel mounted for rotation around a horizontal axis and a plurality of angularly spaced molds disposed around the wheel. Each of the molds includes a first mold segment and a second mold segment disposed radially outwardly of the first mold segment. Each of the second mold segments is movable radially with respect to the associated first mold segment between a radially inner closed position with the first mold segment for compression molding a plastic article, and a radially outer open position spaced from the associated first mold segment for removing a molded article from the mold and placing a mold charge into the mold.
1. A method of compression molding plastic articles, which includes the steps of:
(a) providing a wheel mounted for rotation around a horizontal axis and a plurality of angularly spaced molds disposed around said wheel, each of said molds including a first mold segment and a second mold segment disposed radially outwardly of said first mold segment,
(b) rotating said wheel around said horizontal axis,
(c) as said wheel rotates, radially moving each second mold segment in sequence with respect to the associated first mold segment between a radially inner closed position with said first mold segment and a radially outer open position spaced from the associated first mold segment,
(d) with said mold segments in said open position, removing a molded article from said mold and placing a mold charge into said mold,
(e) closing said mold segments as said wheel rotates to compression mold plastic articles between said mold segments, and
(f) using radial motion of said second mold segment in said step (c) to remove the molded article from the mold in said step (d),
wherein each of said first mold segments includes a male mold segment having a core and a stripper sleeve surrounding said core, and
wherein said step (f) is carried out by operatively coupling at least one abutment to said stripper sleeve and spaced from said second mold segment in said closed position of said molds, said abutment being disposed for engagement by said second mold segment during motion of said second mold segment toward said open position to strip a molded part from said core as said second mold segment is moved radially outwardly toward said open position such that there is lost motion between said second mold segment and said abutment to allow said second mold segment to clear said mold core before initiating motion of said stripper sleeve.
2. The method set forth in claim 1 wherein said step (c) is carried out by positioning a cam adjacent to said wheel for engagement with said molds to open and close said molds in sequence as said wheel rotates.
3. The method set forth in claim 2 wherein said step (c) includes latching said mold segments to each other when said mold segments are in said closed position.