Multiple cavity injection mold

Claim 2

In a multiple cavity injection mold which defines an inner, first mold part positioned between a pair of second mold parts to define a pair of separate mold cavities respectively positioned between the first mold part and each second mold part; means for moving said mold parts in a direction of moving between engaging, mold cavity -forming relation and spaced relation to alternatingly mold and to remove product molded therein; and sprue means to provide molten molding compound to each mold cavity, the improvement comprising, in combination: said sprue means comprising a first sprue conduit extending through one of said second mold parts and communicating between a source of molten molding compound and one of said mold cavities, a second sprue conduit communicating between said first sprue conduit and the other mold cavity through said first mold part, and gate, means conduit.

Claim 3

The injection mold of claim 1 in which said first and second sprue conduits communicate with each other in essentially linear, straight relation, said sprue conduits being free of any sharp turns.

Claim 4

The injection mold of claim 2 in which said sprue conduits extend in the direction of moving of said mold parts.

Claim 5

The injection mold of claim 1 in which said gate means comprises a rotatable member positioned within said first mold part; a passageway extending centrally through said rotatable said member passageway comprising at least a portion of said second sprue conduit; and means for rotating said rotatable member between a first rotary position in which said passageway is in communication between the first sprue conduit and the other mold cavity, and a second rotary position in which said passageway is out of said communication.

Claim 6

The injection mold of claim 4 in which said rotatable member is substantially spherical in shape, said rotatable member defining a recess on its spherical surface that communicates with the one of said mold cavities in the second rotary position, to facilitate distribution of molten molding compound from the first sprue conduit into the one mold cavity.

Claim 7

The injection mold of claim 5 in which said recess is of substantially circular periphery.

Claim 8

The injection mold of claim 5 in which said passageway is essentially sealed from the one mold cavity in the first rotary position.

Claim 9

The injection mold of claim 4 in which means are provided for removing molding compound from said passageway while the rotatable member is in the second rotary position.

Claim 10

The injection mold of claim 8 in which means are provided for cooling said rotatable member to cause molding compound in said passageway to harden.

Claim 11

The injection mold of claim 4 in which means are provided for heating said rotatable member to retain molding compound in said passageway in molten condition.

Claim 12

The injection mold of claim 10 in which said rotatable member is substantially spherical in shape.

Claim 13

The injection mold of claim 11 in which said passageway communicates with the one mold cavity in the first rotary position, whereby both molding chambers can be filled with molding compound in a single shot.

Claim 14

The injection mold of claim 4 in which said rotatable member is of substantially spherical shape.

Claim 15

In a multiple cavity injection mold which defines an inner, first mold part positioned between a pair of second mold parts to define a pair of separate mold cavities respectively positioned between the first mold part and each second mold part; means for moving said mold parts in a direction of moving between engaging, mold cavity-forming relation and spaced relation to alternatingly mold and to remove product molded therein; and sprue means to provide molten molding compound to each mold cavity, the improvement comprising, in combination: said sprue means comprising a first sprue conduit extending through one of said second mold parts and communicating between a source of molten molding compound and one of said mold cavities, a second sprue conduit extending through said first mold part and being in communication between said first sprue conduit and the other mold cavity, said first and second sprue conduits communicating with other in essentially linear, straight relation, and gate means controlling flow through at least said second sprue conduit, said gate means comprising a rotatable member positioned within said first mold part; a passageway extending centrally through said rotatable member and comprising at least a portion of said second sprue conduit; and means for rotating said rotatable member between a first rotary position in which said passageway is in communication between the first sprue conduit and the other mold cavity, and a second rotary position in which said passageway is out of said communication.

Claim 16

In a multiple cavity injection mold which defines an inner, first mold part positioned between a pair of second mold parts to define a pair of separate mold cavities respectively positioned between the first mold part and each second mold part; means for moving said mold parts in a direction of moving between engaging, mold cavity-forming relation and spaced relation to alternatingly mold and to remove product molded therein; and sprue means to provide molten molding compound to each mold cavity, the improvement comprising, in combination: said sprue means comprising a first sprue conduit extending through one of said second mold parts and communicating between a source of molten molding compound and one of said mold cavities, a second sprue conduit extending through said first mold part and being in communication between said first sprue conduit and the other mold cavity, said first and second sprue conduits communicating with other in essentially linear, straight relation, and gate means controlling flow through at least said second sprue conduit, said gate means comprising a rotatable member positioned within said first mold part; a passageway extending centrally through said rotatable member and comprising at least a portion of said second sprue conduit; and means for rotating said rotatable member between a first rotary position in which said passageway is in communication between the first sprue conduit and the other mold cavity, and a second rotary position in which said passageway is out of said communication.

Claim 17

The injection mold of claim 14 in which said sprue conduits extend in the direction of moving of said mold parts, said sprue conduits being free of any sharp turns.

Claim 18

The injection mold of claim 15 in which said rotatable member is substantially spherical in shape, said rotatable member defining a recess on its spherical surface that communicates with the one mold cavity in the second rotary position, to facilitate the distribution of molten molding compound from the first sprue conduit into the one of said mold cavities.

Claim 19

The injection mold of claim 16 in which said passageway is essentially sealed from the one mold cavity in the first rotary position.

Claim 20

The injection mold of claim 17 in which plunger means are provided for removing molding compound from said passageway while the rotatable member is in the secondary rotary position.

Claim 21

The injection mold of claim 18 in which means are provided for cooling said rotatable member to cause molding compound in said passageway to harden.

Claim 22

The injection mold of claim 15 in which means are provided for heating said rotatable member to retain molding compound in said passageway in molten condition.

Claim 23

The injection mold of claim 20 in which said rotatable member is substantially spherical in shape.

Claim 24

The injection mold of claim 21 in which said passageway communicates with the one of said mold cavities in the first rotary position, whereby both molding chambers can be filled with molding compound in a single shot.

Claim 25

In an injection mold which defines a first mold part and a second mold part which together define a mold cavity between them; means for moving said mold parts between engaging, mold cavity-forming relation and spaced relation to alternatingly mold and to remove product molded therein; and sprue means to provide molten molding compound to said mold cavity, the improvement comprising, in combination: said sprue means comprising a first sprue conduit communicating between a source of molten molding compound and a second sprue conduit, said first and second sprue conduits communicating with each other in essentially linear, straight relation, said second sprue conduit communicating between the first sprue conduit and the mold cavity, said second sprue conduit comprising a passageway extending centrally through a rotatable member; means for rotating said rotatable member between a first rotary position in which said passageway is in communication between the first sprue conduit and the mold cavity, and a second rotary position in which said passageway is out of said communication, said rotatable member being substantially spherical in shape, said spherical rotatable member defining a circular recess on its spherical surface that communicates with the mold cavity in the second rotary position, to facilitate distribution of molten molding compound from the first sprue conduit into the mold cavity.

Claim 26

In an injection mold which defines a first mold part and a second mold part which together define a mold cavity between them; means for moving said mold parts between engaging, mold cavity-forming relation and spaced relation to alternatingly mold and to remove product molded therein; and sprue means to provide molten molding compound to said mold cavity, the improvement comprising, in combination: said sprue means comprising a first sprue conduit communicating between a source of molten molding compound and a second sprue conduit, said first and second sprue conduits communicating with each other in essentially linear, straight relation, said second sprue conduit communicating between the first sprue conduit and the mold cavity, said second sprue conduit comprising a passageway extending centrally through a rotatable member; means for rotating said rotatable member between a first rotary position in which said passageway is in communication between the first sprue conduit and the mold cavity, and a second rotary position in which said passageway is out of said communication, said rotatable member being substantially spherical in shape, said spherical rotatable member defining a circular recess on its spherical surface that communicates with the mold cavity in the second rotary position, to facilitate distribution of molten molding compound from the first sprue conduit into the mold cavity.

Claim 27

The injection mold of claim 23 in which means are provided for heating said rotatable member to retain molding compound in said passageway in molten condition, outer portions of said rotatable member comprising insulating material, whereby said rotatable member can rotate to present said insulating material to said mold cavity in the second rotary position.