High cavitation, low tonnage rubber mold machine and method

1. A rubber injection molding apparatus for simultaneously molding a plurality of work parts in separate molds using a single press machine, said apparatus comprising:

a rubber injection press machine including a press bed and a vertically oriented press ram supported for reciprocating movement in a generally vertical path toward and away from said press bed;

a plurality of separate and distinct injection molds positioned between said press bed and said press ram, each of said molds having two mold halves joining one another along a parting line interface with a mold cavity defined between each of said mold halves;

a supply of molten rubber communicating with said press ram;

a clamping mechanism directly responsive to the vertical motion of said press ram for compressing said plurality of molds in a direction normal to each of said parting lines;

and each of said molds being horizontally arrayed relative to one another such that each of said parting lines are disposed generally parallel to the movement of the press ram, whereby the generally vertical motion of said press ram is converted into a generally horizontal clamping force by said clamping mechanism and thereby simultaneously compressing all of said molds together.

2. The apparatus of claim 1 wherein said clamping mechanism includes at least one moveable wedge directly connected to the press ram and one co-acting stationary wedge directly connected to said press bed, said moveable wedge and said stationary wedge interacting with one another in response to reciprocating movement of said press ram.

3. The apparatus of claim 2 wherein said press machine includes a first rail extending parallel to the direction of said clamping force, said mold halves being suspended from said first rail.

4. The apparatus of claim 3 wherein said press machine includes a second rail spaced parallel from said first rail and cooperatively suspending said mold halves therebetween.

5. The apparatus of claim 4 further including a plurality of carriers directly connected to said first and second rails, each said carrier supporting at least one of said mold halves.

6. The apparatus of claim 5 further including a taper registration interface between said mold half and said carrier.

7. The apparatus of claim 6 wherein each of said mold halves includes a lateral edge, said taper registration interface including a bead on said lateral edge for mating with a complementary groove in said carrier.

8. The apparatus of claim 7 further including a gate formed between mating said mold halves, said gate proximate said lateral edge.

9. The apparatus of claim 8 wherein said gate comprises an edge gate configuration style.

10. The apparatus of claim 1 further including at least one locator pin and a mating socket disposed between respective mating pairs of said mold halves.

11. A method for simultaneously molding a plurality of work parts in separate molds using a single press machine, said method comprising the steps of:

providing a rubber injection press machine having a moveable press ram and a stationary press bed;

reciprocating the press ram in a generally vertical path toward and away from the press bed;

providing a plurality of separate and distinct injection molds each having two mold halves joining one another along a parting line interface with a mold cavity between opposing mold halves;

positioning the molds in the vertical path between the press bed and the press ram in a horizontally extending array such that each of the parting lines are disposed generally parallel to the movement of the press ram;

supplying molten rubber to the press ram;

compressing the plurality of molds together in response to the reciprocating motion of the press ram;

and said compressing step further including converting the generally vertical motion of the press ram into a generally horizontal clamping force and thereby simultaneously compressing all of said molds together while filling the cavities with molten rubber.

12. The method of claim 11 wherein said compressing step further includes co-acting at least one moveable wedge connected to the press ram and one stationary wedge connected to the press bed.

13. The method of claim 11 wherein said step of positioning the molds in the vertical path includes the step of suspending the mold halves from at least one rail extending parallel to the direction of the compressing force.

14. The method of claim 11 wherein said step of positioning the molds in the vertical path includes the step of suspending the mold halves from a pair of spaced rails extending parallel to the direction of the compressing force.

15. The method of claim 14 further including the step of supporting each mold half in a carrier, the carrier being supported directly upon and slideable along the pair of spaced rails.

16. The method of claim 11 further including the step of removing a molded work part from the mold cavity with the assistance of gravity.

17. The method of claim 16 wherein said step of removing a molded part includes inserting a sweeper between the opposing mold halves.