Partially rotated eccentric drive for valve pin

A method of injecting a selected injection fluid (9) into a cavity (80) of a mold (70) in an injection molding apparatus (5) comprised of an injection molding machine (IMM), a heated manifold (60) that receives injection fluid (9) from the injection molding machine and distributes the injection fluid through a fluid distribution channel (120), a mold (70) having a cavity (80) and one or more valves (50) having a valve pin (100) that controls injection of the injection fluid (9) into the mold cavity, the method comprising:

• selecting an electrically driven actuator (200) having a driven rotatable rotor drivably rotatably interconnected to an output shaft (12) or to an output rotation device (16, 430, 500) that is rotatably driven around an output rotation axis (12a, R3a),
• disposing or mounting an eccentric (600) eccentrically off center a selected distance (ED, R) from the output rotation axis (12a, R3a) in an arrangement such that when the shaft (12) or rotation device (16, 430, 500) is rotatably driven, the eccentric (600) is eccentrically rotatably driven around the output rotation axis (12a, R3a),
• controllably rotating the shaft (12) or output rotation device (16, 430, 500) during the course of an entire injection cycle to angular positions between about 70 degrees above and 70 degrees below the 270 degree position or between about 70 degrees above and 70 degrees below the 90 degree position,
• wherein a preselected angular position between the 270 or 90 degree position and 70 degrees above defines a fully open valve pin position (PFO) and a preselected angular position between the 270 or 90 degree position and 70 degrees below defines a valve pin position where the gate is closed (PFC),
• interconnecting to or interengaging with the pin or shaft (100) the driven cam member (600) in an arrangement such that the pin or shaft (100) is drivable reciprocally along a linear path of travel (A) as the eccentric (600) is eccentrically rotatably driven,
• controllably operating the electrically driven actuator to drive the pin or shaft (100).

An injection molding apparatus (5) comprising an injection molding machine (IMM), a heated manifold (60) that receives injection fluid (9) from the injection molding machine and distributes the injection fluid through a fluid distribution channel (120), a mold (70) having a cavity (80) and one or more valves (50) having a valve pin (100) that controls injection of the injection fluid (9) into the mold cavity, the one or more valves (50) being comprised of:

• an electrically driven actuator (200) having a driven rotatable rotor drivably rotatably interconnected to a shaft (12) or to an output rotation device (16, 430, 500) that is rotatably drivable 360 degrees around an output rotation axis (12a, R3a),
• a rotary to linear converter device that includes an eccentric (600) that is eccentrically disposed or mounted off center a selected distance (ED, R) from the output rotation axis (12a, R3a) in an arrangement such that when the shaft (12) or rotation device (16, 430, 500) is rotatably driven, the eccentric (600) is eccentrically rotatably drivable around the output rotation axis (12a, R3a) to selectable angular positions above and below either a 270 degree position or a 90 degree position,
• a controller interconnected to the shaft (12) or output rotation device (16, 430, 500), the controller including an algorithm that controllably limits rotation of the shaft (12) or output rotation device (16, 430, 500) during the course of an entire injection cycle to selectable angular positions that create a moment arm that extends between a selected minimum moment arm and a selected maximum moment arm, the selectable angular positions being between 70 degrees above and 70 degrees below an angular position that corresponds to the selected maximum moment arm,
• the pin or shaft (100) being interconnected to or interengaged with the driven eccentric (600) in an arrangement such that the pin or shaft (100) is driven reciprocally along a linear path of travel (A) as the eccentric (600) is eccentrically rotatably driven.

A method of injecting a selected injection fluid (9) into a cavity (80) of a mold (70) in an injection molding apparatus (5) comprised of an injection molding machine (IMM), a heated manifold (60) that receives injection fluid (9) from the injection molding machine and distributes the injection fluid through a fluid distribution channel (120), a mold (70) having a cavity (80) and one or more valves (50) having a valve pin (100) that controls injection of the injection fluid (9) into the mold cavity, the method comprising:

• selecting an electrically driven actuator (200) having a driven rotatable rotor drivably rotatably interconnected to an output shaft (12) or to an output rotation device (16, 430, 500) that is rotatably driven around an output rotation axis (12a, R3a),
• disposing or mounting an eccentric (600) eccentrically off center a selected distance (ED, R) from the output rotation axis (12a, R3a) in an arrangement such that when the shaft (12) or rotation device (16, 430, 500) is rotatably driven, the eccentric (600) is eccentrically rotatably driven around the output rotation axis (12a, R3a),
• controllably rotating the shaft (12) or output rotation device (16, 430, 500) during the course of an entire injection cycle to selectable angular positions that create a moment arm that extends between a selected minimum moment arm and a selected maximum moment arm, the selectable angular positions being between 70 degrees above and 70 degrees below an angular position that corresponds to the selected maximum moment arm,
• interconnecting to or interengaging with the pin or shaft (100) the driven cam member (600) in an arrangement such that the pin or shaft (100) is drivable reciprocally along a linear path of travel (A) as the eccentric (600) is eccentrically rotatably driven,
• controllably operating the electrically driven actuator to drive the pin or shaft (100).