Ejector apparatus for molding machine

Claim 2

A molding machine having relatively movable platens and mold portions removably mounted on said platens and which mold portions define a cavity in which a part is molded, a plurality of ejector pins in one of said mold portions, said pins being slidable within said one portion to cause projection of said pins into said cavity thereby to eject a part therefrom, an ejector plate mounted rearwardly of a first of said platens upon which said one mold portion is mounted, said ejector plate being mounted for movement toward and away from said first platen, said ejector plate being normally positioned in spaced relation to said first platen, said first platen having a plurality of openings therethrough in a regular array arranged generally over the entire area of said first platen for slidably receiving in selected ones thereof ejector rods, a plurality of ejector rods slidably mounted in selected ones of said first platen openings, said ejector rods being substantially aligned one with each of said ejector pins and adapted upon movement of said ejector plate from said normal position thereof to be moved forwardly to engage and move said ejector pins forwardly thereby ejecting a part from said cavity, said array of openings permitting utilization of said first platen with a plurality of molds having differing mold configurations and differing arrangements of ejector pins.

Claim 3

A molding machine as set forth in claim 1 wherein resilient means are operatively arranged with each of said ejector pins to bias the same out of said cavity.

Claim 4

A molding machine as set forth in claim 1 wherein each of said ejector pins comprises a small shank and an enlarged head portion for engagement by an ejector rod whereby to permit latitude of location of an ejector pin with respect to an ejector rod.

Claim 5

A molding machine as set forth in claim 1 wherein each of said ejector pins comprises a shank and an enlarged head portion sliding within a counterbore in said one mold portion, and compression spring means are operatively arranged in said counterbores to engage each said head portion and bias said pins to a withdrawn position with respect to said cavity, and stop means in said mold limiting the movement of said ejector pins under the bias of said springs.

Claim 6

A molding machine as set forth in claim 1 wherein said first platen is a fixed platen.

Claim 7

A molding machine as set forth in claim 1 comprising plastic injecting means operatively arranged with said first platen for injecting said cavity through said one mold portion.

Claim 8

In an injection molding machine having a fixed platen and a movable platen for mounting thereon of a core side and a cavity side, respectively, of a mold, said fixed platen having a plurality of openings therethrough for slidably receiving ejector rods in selected ones of said openings, an ejector plate mounted rearwardly of said fixed platen for movement toward and away from said fixed platen, means operatively connected to said ejector plate for moving said ejector plate toward said fixed platen to cause said ejector rods to be extended from the forward surface of said fixed platen, a core side of a mold mounted on said fixed platen and having in the front surface thereof opposite said fixed platen a cavity defining at least a portion of a part to be injection molded, said mold core side having a plurality of openings therethrough extending from said cavity to the rear surface abutting sAid fixed platen, said openings being counterbored from said rear surface, a plurality of ejector pins mounted one in each of said mold core side openings for sliding movement therein, said ejector pins each comprising an enlarged head slidably received with the counterbore of the corresponding opening, stop means operatively associated with each of said ejector pins to limit the rearward movement of said pins, spring means operatively arranged with each of said ejector pins for biasing the head thereof against said stop means, said ejector pins being so positioned that the head of each will be engaged by an ejector rod upon forward movement of the latter thereby to cause forward movement of said ejector pins to eject a part molded in said cavity, and a plurality of ejector rods arranged within said openings in said fixed platen, there being an ejector rod aligned one with each of said ejector pins.

Claim 9

In an injection molding machine having a fixed platen and a movable platen for mounting thereon of a core side and a cavity side, respectively, of a mold, said fixed platen having a plurality of openings therethrough for slidably receiving ejector rods in selected ones of said openings, an ejector plate mounted rearwardly of said fixed platen for movement toward and away from said fixed platen, means operatively connected to said ejector plate for moving said ejector plate toward said fixed platen to cause said ejector rods to be extended from the forward surface of said fixed platen, a core side of a mold mounted on said fixed platen and having in the front surface thereof opposite said fixed platen a cavity defining at least a portion of a part to be injection molded, said mold core side having a plurality of openings therethrough extending from said cavity to the rear surface abutting sAid fixed platen, said openings being counterbored from said rear surface, a plurality of ejector pins mounted one in each of said mold core side openings for sliding movement therein, said ejector pins each comprising an enlarged head slidably received with the counterbore of the corresponding opening, stop means operatively associated with each of said ejector pins to limit the rearward movement of said pins, spring means operatively arranged with each of said ejector pins for biasing the head thereof against said stop means, said ejector pins being so positioned that the head of each will be engaged by an ejector rod upon forward movement of the latter thereby to cause forward movement of said ejector pins to eject a part molded in said cavity, and a plurality of ejector rods arranged within said openings in said fixed platen, there being an ejector rod aligned one with each of said ejector pins.