A hot-runner injection molding apparatus that facilitates use of electric actuators in a compact design includes a hot-runner manifold defining resin channels for conveying resin to nozzles that serve as conduits for introducing liquid resin into a mold cavity, a valve pin configured for linear movement along a longitudinal axis of the nozzle to control flow of liquid resin through the nozzle, and an electric actuator having a body containing an electric motor, wherein the electric actuator body includes channels for circulating a coolant.

A hot-runner injection molding apparatus that facilitates use of electric actuators in a compact design includes a hot-runner manifold defining resin channels for conveying resin to nozzles that serve as conduits for introducing liquid resin into a mold cavity, a valve pin configured for linear movement along a longitudinal axis of the nozzle to control flow of liquid resin through the nozzle, and an electric actuator having a body containing an electric motor, wherein the electric actuator body includes channels for circulating a coolant.

An injection molding apparatus (5) comprising: an actuator (10) comprising a thermally conductive housing body (12) mounted in direct heat or thermally conductive contact with one or more mounts (60, 50, 803) that are in turn mounted in direct heat conductive contact or communication with the manifold (20), the cooling device (500, 800) comprising a heat transmitter comprised of an arm, member (502) or leg (800I) that is either: disposed in direct or integral thermal contact with a complementary surface (12Is) of the actuator (10) or, configured to have compressible spring joints (800s).

An injection molding apparatus and method for adjusting the axial position of a valve pin in an injection molding system, the apparatus comprising: a top clamp plate, a heated manifold receiving and distributing an injection fluid to an exit of a fluid delivery channel to a cavity of the mold, an actuator comprising a housing having a chamber enclosing a drive member for driving a valve pin along an axial path of travel, the actuator housing slidably mounted and adapted for controlled upstream and downstream movement of the drive member along a path complementary to the axial path of travel of the valve pin, a mounting plate and an axial position adjustment screw screwably mounted within the mounting plate upstream of the housing of the actuator for controllably moving the valve pin to selectable starting or ending injection cycle axial positions.

A method is described for operating an actuator (10) adapted for moving by means of a pressurized fluid the shutter (12) of an injection nozzle for molten material into a mould, wherein the shutter (12) moves from a closing position, in which there is no passage of molten material through the nozzle, to an opening position, in which there is passage of molten material through the nozzle, and the shutter (12) comprises a chamber (18), and a piston (14) which is movably mounted in the chamber (18), displaced linearly thanks to the thrust of the fluid and connected to the shutter (12) to move it.

The shutter (12) is moved by inserting or removing the predetermined amount of fluid into/from the chamber (18).

A method is described for operating an actuator (10) adapted for moving by means of a pressurized fluid the shutter (12) of an injection nozzle for molten material into a mould, wherein the shutter (12) moves from a closing position, in which there is no passage of molten material through the nozzle, to an opening position, in which there is passage of molten material through the nozzle, and the shutter (12) comprises a chamber (18), and a piston (14) which is movably mounted in the chamber (18), displaced linearly thanks to the thrust of the fluid and connected to the shutter (12) to move it. The shutter (12) is moved by inserting or removing the predetermined amount of fluid into/from the chamber (18).

A system is disclosed for driving an actuator which comprises a chamber, a shutter of an injection nozzle for molten material for injection molding, and a piston translatable inside the chamber to actuate a shutter. Means are provided for the transfer of a predetermined amount of fluid between the outside and inside of the chamber, so as to bring/move the shutter from a closing position, in which there is no passage of molten material, towards an opening position, in which there is passage of molten material, by injecting the predetermined amount of fluid from the outside into the chamber or by injecting the predetermined amount of fluid from the chamber towards the outside, or vice versa.

An injection molding apparatus (5), comprising: a first fluid drive cylinder (940c, 941c, 942c), a second fluid drive cylinder (940ac, 941ac, 942ac) interconnected to a valve pin (1040, 1041, 1042), wherein the first fluid drive cylinder (940c, 941c, 942c) and the second fluid drive cylinder (940ac, 941ac, 942ac) are interconnected in an arrangement wherein reciprocating movement of a piston (940p, 941p, 942p) of the first cylinder drives concomitant back and forth movement of a piston (940ap, 941ap, 942ap) of the second cylinder and concomitant back and forth movement of the valve pin (1040, 1041, 1042); an electrically powered actuator (940, 941, 942) adapted to drive the piston of the first cylinder reciprocally according to a drive program such that the valve pin (1040, 1041, 1042) is driven between gate closed and gate open positions and selected positions therebetween.

A device is described for adjusting the linear position of one or more shutters (20) in an injection moulding system. The device comprises a body, comprising a cavity in which there can axially slide a movable element, and an adjustment element for adjustment of the axial position of the body with respect to a plate. The adjustment element is rotatably mounted between the body and the plate and comprises a threaded portion on which a corresponding thread of the body and/or of the plate is engaged.

A device is described for adjusting the linear position of one or more shutters (20) in an injection moulding system. The device comprises a body, comprising a cavity in which there can axially slide a movable element, and an adjustment element for adjustment of the axial position of the body with respect to a plate. The adjustment element is rotatably mounted between the body and the plate and comprises a threaded portion on which a corresponding thread of the body and/or of the plate is engaged.