Actuator with eccentric pin drive
An injection molding apparatus ( 5 ) comprising 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 ( 12 a , R 3 a ) and a cam device or surface ( 600 ) that is eccentrically disposed or mounted off center a selected distance (ED) from the output rotation axis ( 12 a , R 3 a ) in an arrangement such that when the shaft ( 12 ) or rotation device ( 16, 430, 500 ) is rotatably driven, the cam member or surface ( 600 ) is eccentrically rotatably driven around the output rotation axis ( 12 a , R 3 a ).
1. 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 or shaft ( 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 an output shaft ( 12 ) or to an output rotation device ( 16 , 430 , 500 ) that is rotatably driven around an output rotation axis ( 12 a , R 3 a ),
the pin or shaft ( 100 ) being interconnected to or interengaged with the output shaft ( 12 ) or the output rotation device ( 16 , 430 , 500 ) in an arrangement such that the pin or shaft ( 100 ) is driven reciprocally along a linear path of travel (A),
wherein the one or more valves include a rotational speed reducing mechanism ( 46 ) interconnected to the output shaft or rotor ( 12 ) of the actuator ( 200 ),
the rotational speed reducing mechanism ( 46 ) being comprised of a rotatably driven body having a generally elliptical or other noncircular shaped outer circumferential surface ( 430 , 472 ) interconnected to the output shaft or rotor ( 12 ) in an arrangement such that rotation of the output shaft or rotor ( 12 ) is transmitted to the output rotation device ( 16 , 430 , 500 ) to cause the output rotation device ( 16 , 430 , 500 ) to be rotatably driven at a selected lower rotational speed relative to a rotational speed of the output shaft or rotor ( 12 ).
2. The apparatus of claim 1 including a cam device or surface ( 600 ) adapted to be eccentrically rotatably driven around the output rotation axis ( 12 a , R 3 a ),
the pin or shaft ( 100 ) being interconnected to or interengaged with the output shaft ( 12 ) or the output rotation device ( 16 , 430 , 500 ) in an arrangement such that the pin or shaft ( 100 ) is driven reciprocally along a linear path of travel (A) as the cam member ( 600 ) is eccentrically rotatably driven.
3. The apparatus of claim 2 wherein the output rotation device ( 16 , 430 , 500 ) is interconnected to the rotor or output shaft ( 12 ) in an arrangement such that the output rotation device ( 16 , 430 , 500 ) is controllably rotatably drivable by controllable driven rotation of the rotor or output shaft ( 12 ), the cam device or surface ( 600 ) being eccentrically disposed or mounted off center a selected distance (ED) from the output rotation axis (R 3 a ) of the output rotation device ( 16 , 430 , 500 ).
4. The apparatus of claim 2 further comprising a slide or sled ( 43 ) that has a cammed slot ( 43 sl ) having a slot surface ( 43 ss ) adapted to engage an exterior surface ( 600 cs ) of the cam device or surface ( 600 ) to cause the sled or slide ( 43 ) to move along the linear path of travel (A) as the cam member ( 600 ) is eccentrically rotatably driven around the output rotation axis ( 12 a , R 3 a ).
5. The apparatus of claim 1 wherein the rotational speed reducing mechanism comprises a strain wave gear.
6. The apparatus of claim 1 wherein the electrically driven actuator ( 200 ) is mounted in a remote location or position relative to the heated manifold ( 60 ) such that the electrically driven actuator ( 200 ) is insulated or isolated from thermal communication with the heated manifold ( 60 ).
7. The apparatus of claim 1 wherein an elongated shaft ( 20 , 20 f ) drivably interconnects the rotatable output shaft ( 12 ) or the output rotation device ( 16 , 430 , 500 ) to a rotary to linear converter ( 40 ) that is interconnected to the pin or shaft ( 100 ) to convert rotation of the output shaft ( 12 ) or the output rotation device ( 16 , 430 , 500 ) to linear motion and drive the pin or shaft ( 100 ) linearly.
8. The apparatus of claim 7 wherein the elongated shaft has a length (CL) sufficient to mount the actuator ( 200 ) in a position or location remote from the heated manifold ( 60 ) such that the actuator ( 200 ) is isolated from substantial heat communication with the heated manifold ( 60 ) wherein the actuator remains interconnected to the valve pin ( 100 ) via the one or more elongated cables ( 20 , 20 f ).
9. The apparatus of claim 1 wherein an elongated cable or shaft ( 20 f ) having a length (CL) and a cable axis (CA) that is flexibly bendable along at least a portion of the cable axis (CA) into a curved or curvilinear configuration (CF) interconnects the rotatable output shaft ( 12 ) or the output rotation device ( 16 , 430 , 500 ) to a rotary to linear converter ( 40 ) that is interconnected to the pin or shaft ( 100 ) to convert rotation of the output shaft ( 12 ) or the output rotation device ( 16 , 430 , 500 ) to linear motion and drives the pin or shaft ( 100 ) linearly.
10. The apparatus of claim 2 wherein the cam device or surface ( 600 ) comprises a disk, wheel, pin or projection ( 600 p ) projecting axially from a rotatable member ( 500 ) that is controllably rotatable around a rotation axis (R 3 a ) or comprises a radial surface ( 600 cs ) of a rotatable member ( 500 ) controllably rotatable around a rotation axis (R 3 a ).
11. The apparatus of claim 10 wherein the valve pin ( 100 ) is maintained in engagement with the radial surface ( 600 cs ) under a spring force (SF).
12. 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 ( 12 a , R 3 a ),
interconnecting a rotational speed reducing mechanism ( 46 ) to the output shaft or rotor ( 12 ) or output rotation device ( 16 , 430 , 500 ) of the actuator ( 200 ),
disposing or mounting a cam device or surface ( 600 ) eccentrically off center a selected distance (ED) from the output rotation axis ( 12 a , R 3 a ) in an arrangement such that when the shaft ( 12 ) or rotation device ( 16 , 430 , 500 ) is rotatably driven, the cam member or surface ( 600 ) is eccentrically rotatably driven around the output rotation axis ( 12 a , R 3 a ),
interconnecting to or interengaging with the pin or shaft ( 100 ) the driven cam device or surface ( 600 ) in an arrangement such that the pin or shaft ( 100 ) is drivable reciprocally along a linear path of travel (A) as the cam member ( 600 ) is eccentrically rotatably driven,
controllably operating the electrically driven actuator to drive the pin or shaft ( 100 ),
wherein the rotational speed reducing mechanism is selected to comprise a rotatably driven body having a generally elliptical or other noncircular shaped outer circumferential surface ( 430 , 472 ) interconnected to the output shaft or rotor ( 12 ) in an arrangement such that rotation of the output shaft or rotor ( 12 ) is transmitted to the output rotation device ( 16 , 430 , 500 ) to cause the output rotation device ( 16 , 430 , 500 ) to be rotatably driven at a selected lower rotational speed relative to a rotational speed of the output shaft or rotor ( 12 ).
13. A method of performing an injection molding cycle comprising operating an injection molding apparatus according to claim 1 .