Patent Publication Number: US-10322537-B2

Title: Valve pin position adjuster

Description:
RELATED APPLICATIONS 
     This application is a continuation of and claims the benefit of priority to U.S. application Ser. No. 14/950,004 filed Nov. 24, 2015 which is a continuation of PCT/US2014/039932 filed May 29, 2014 which claims the benefit of priority of U.S. Provisional Application Ser. No. 61/828,391 filed May 29, 2013. 
     The disclosures of all of the following are incorporated by reference in their entirety as if fully set forth herein: U.S. Pat. Nos. 5,894,025, 6,062,840, 6,294,122, 6,309,208, 6,287,107, 6,343,921, 6,343,922, 6,254,377, 6,261,075, 6,361,300, 6,419,870, 6,464,909, 6,599,116, 7,234,929, 7,419,625, 7,569,169, U.S. patent application Ser. No. 10/214,118, filed Aug. 8, 2002, U.S. Pat. Nos. 7,029,268, 7,270,537, 7,597,828, U.S. patent application Ser. No. 09/699,856 filed Oct. 30, 2000, U.S. patent application Ser. No. 10/269,927 filed Oct. 11, 2002, U.S. application Ser. No. 09/503,832 filed Feb. 15, 2000, U.S. application Ser. No. 09/656,846 filed Sep. 7, 2000, U.S. application Ser. No. 10/006,504 filed Dec. 3, 2001, and U.S. application Ser. No. 10/101,278 filed Mar. 19, 2002 and U.S. application Ser. No. 13/484,336 filed May 31, 2012 and U.S. application Ser. No. 13/484,408 filed May 31, 2012. 
    
    
     BACKGROUND OF THE INVENTION 
     Injection molding systems powered by hydraulically driven actuators typically utilize the hydraulic system to adjust the initial positioning of the valve pin by driving the piston of the actuator, the housing or cylinder of which is fixedly attached to the hotrunner manifold such that the housing is stationary in the axial direction relative to the manifold. Other systems have been developed using a screw that forms a portion of the actuator housing. 
     SUMMARY OF THE INVENTION 
     An apparatus for adjusting the axial position of a valve pin in an injection molding system, the apparatus comprising: 
     an actuator comprising a housing having a chamber enclosing a drive member that is fixedly interconnectable to the valve pin, the drive member driving the valve pin reciprocally upstream and downstream along an axial path of travel through a fluid delivery channel having an exit to a cavity of a mold which is reciprocally opened and closed by reciprocal downstream and upstream driven movement of a tip end of the valve pin into and out of the exit of the fluid delivery channel,
         the actuator housing being slidably mounted upstream of the fluid delivery channel 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,   the adjustment screw being controllably screwable clockwise and counterclockwise within the mounting plate to move along an upstream and downstream path complementary to the axial path of travel of the drive member and the valve pin,   the valve pin being movable to selectable starting or ending injection cycle axial positions upon interconnection of the valve pin to the drive member, clockwise or counterclockwise screwing of the adjustment screw within the mounting plate to corresponding selectable axial positions and subsequent interconnection of the adjustment screw to the actuator.       

     The drive member is preferably interconnectable to and disconnectable from the valve pin externally of the enclosure of the housing of the actuator while the enclosure is enclosed. 
     The apparatus typically further comprises a coupling that interconnects an upstream end of the valve pin to the axial drive device, the coupling being accessible for interconnection and disconnection of the valve pin while the enclosure is enclosed. 
     The actuator typically comprises a fluid driven actuator, the enclosure of the actuator comprising a fluid sealed chamber, the axial drive device comprising a piston slidably mounted within the fluid sealed chamber. 
     The mounting plate is typically fixedly mounted to either a fluid delivery manifold or a top clamping plate in an arrangement such that the adjustment screw is rotatable to axially adjust the valve pin to selectable upstream and downstream axial positions. 
     The manifold is preferably disposed between the mounting plate and the exit of the fluid delivery channel, the manifold having a fluid distribution channel delivering injection fluid to the fluid delivery channel. 
     The top clamp plate is typically disposed upstream of the manifold. 
     The actuator housing is preferably mounted for axial movement without rotation. 
     The apparatus can further comprise a top clamp plate interconnected to a mold containing a cavity with which the exit of the fluid delivery channel communicates, a heated manifold that delivers heated injection fluid to the fluid delivery channel and an injection molding machine that delivers heated injection fluid to the heated manifold. 
     In another aspect of the invention there is provided a method of adjusting an axial position of a valve pin in an injection molding system comprising an actuator comprised of a housing that forms an enclosure that contains a controllably drivable axial drive device interconnectable to and adapted to drive a valve pin reciprocally upstream and downstream along an axial path of travel through a fluid delivery channel having an exit which is reciprocally opened and closed by reciprocal upstream and downstream driven movement of a distal tip end of the valve pin into and out of the exit of the fluid delivery channel, 
     wherein the actuator is mounted upstream of the fluid delivery channel and adapted for controlled upstream and downstream movement of the actuator and the drive member along a path complementary to the axial path of travel of the valve pin, 
     the apparatus including a mounting plate and an axial position adjustment screw screwably mounted within the mounting plate upstream of the housing of the actuator, the adjustment screw being controllably screwable clockwise and counterclockwise within the mounting plate to move along an upstream and downstream path complementary to the axial path of travel of the drive member and the valve pin, 
     the method comprising: 
     screwing the adjustment screw clockwise or counterclockwise a selected degree of rotation within the mounting plate to position the adjustment screw at a selected axial position along its axial path of movement, 
     moving the actuator along the axial direction complementary to the axial path of travel of the valve pin, 
     Such a method can further comprise fixedly interconnecting the adjustment screw to the actuator housing to controllably move the actuator and the valve pin to a preselected axial starting or ending injection cycle position along the axial path of movement of the valve pin as predetermined by the selected degree of screwable rotation of the adjustment screw. 
     Such a method preferably further comprises interconnecting and disconnecting the valve pin to and from the axial drive device externally of the actuator housing while the enclosure is enclosed and contains the axial drive device. 
     Such a method preferably further comprises moving the actuator housing along its axial path of movement without rotation. 
     The apparatus used in such a method preferably has the mounting plate fixedly mounted to either a fluid delivery manifold or a top clamping plate in an arrangement such that the adjustment screw is rotatable to adjust the valve pin to move to selectable upstream and downstream axial positions. 
     The apparatus used in such a method preferably has the manifold mounted between the actuator and the exit of the fluid delivery channel, the manifold having a fluid distribution channel delivering injection fluid to the fluid delivery channel. 
     The apparatus used in such a method preferably has the top clamp plate disposed upstream of the manifold. 
     In another aspect of the invention there is provided an apparatus for adjusting the axial position of a valve pin in an injection molding system, the apparatus comprising: 
     an actuator comprised of a housing that forms a chamber that contains a drive member interconnected to and adapted to drive a valve pin reciprocally upstream and downstream along an axial path of travel through a fluid delivery channel having an exit which is reciprocally opened and closed by reciprocal upstream and downstream driven movement of a distal tip end of the valve pin into and out of the exit of the fluid delivery channel, 
     a mounting plate and an adjustment screw screwably mounted within the mounting plate, the mounting plate and adjustment screw being arranged such that the adjustment screw is controllably movable along an axial path complementary to the axial path of travel of the valve pin by controlled clockwise and counterclockwise screwable movement of the adjustment screw within the mounting plate, 
     the actuator housing being slidably mounted upstream of the fluid delivery channel 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, 
     the adjustment screw being controllably screwable clockwise and counterclockwise within the mounting plate to move along an upstream and downstream path complementary to the axial path of travel of the drive member and the valve pin, 
     the valve pin being movable to selectable starting or ending injection cycle axial positions upon interconnection of the valve pin to the drive member, clockwise or counterclockwise screwing of the adjustment screw within the mounting plate to corresponding selectable axial positions and subsequent interconnection of the adjustment screw to the actuator, 
     the drive member being interconnectable to and disconnectable from the valve pin externally of the chamber of the housing of the actuator while the chamber is enclosed and contains the drive member. 
     Such an apparatus preferably further comprises a coupling that interconnects an upstream end of the valve pin to the axial drive device, the coupling being accessible for interconnection to and disconnection from the valve pin while the chamber is enclosed and contains the drive member. 
     The mounting plate and adjustment screw are preferably mounted separate and spaced upstream apart from the actuator housing. 
     The actuator can include a fluid driven actuator, the enclosure of the actuator comprising a fluid sealed chamber, the axial drive device comprising a piston slidably mounted within the fluid sealed chamber. 
     The mounting plate is preferably fixedly mounted to either a fluid delivery manifold or a top clamping plate in an arrangement such that the adjustment screw is rotatable to axially adjust the valve pin to selectable upstream and downstream axial positions. 
     The manifold is preferably disposed between the mounting plate and the exit of the fluid delivery channel, the manifold having a fluid distribution channel delivering injection fluid to the fluid delivery channel. 
     The top clamp plate is preferably disposed upstream of the manifold. 
     The actuator housing is preferably mounted for axial movement without rotation. 
     Such an apparatus typically further comprises a top clamp plate interconnected to a mold having a cavity with which the exit of the fluid delivery channel communicates, a heated manifold that delivers heated injection fluid to the fluid delivery channel and an injection molding machine that delivers heated injection fluid to the heated manifold. 
     In another aspect of the invention there is provided an apparatus for adjusting the axial position of a valve pin in an injection molding system, the apparatus comprising: 
     an actuator comprised of a housing that forms and encloses a chamber that contains a controllably drivable axial drive device interconnected to and adapted to drive a valve pin reciprocally upstream and downstream along an axial path of travel through a fluid delivery channel having an exit which is reciprocally opened and closed by reciprocal upstream and downstream driven movement of a distal tip end of the valve pin into and out of the exit of the fluid delivery channel, 
     a mounting plate and adjustment screw mounted upstream, spaced apart and separate from the actuator housing, the mounting plate being mounted in an axially stationary position relative to the exit of the fluid delivery channel, 
     the adjustment screw being screwably mounted within the mounting plate such that the adjustment screw is controllably movable along a path complementary to the axial path of travel of the valve pin by controlled clockwise and counterclockwise screwable movement of the adjustment screw within the mounting plate, 
     the actuator housing being mounted for upstream and downstream axial movement of the axial drive device along a path complementary to the axial path of travel of the valve pin, 
     the adjustment screw being readily fixedly interconnectable to and detachable from the actuator housing such that the axial drive device and valve pin are controllably movable together upstream and downstream to selectable axial positions when the adjustment screw and actuator housing are fixedly interconnected to each other, 
     the distal tip end of the valve pin being controllably positionable at selectable axial positions relative to the exit by controlled clockwise and counterclockwise screwing of the adjustment screw within the mounting plate when the adjustment screw is fixedly interconnected to the actuator housing. 
     The axial drive device is preferably interconnectable to and disconnectable from the valve pin externally of the chamber while the chamber is enclosed and contains the axial drive device. 
     The apparatus can further comprise a coupling that interconnects an upstream end of the valve pin to the axial drive device, the coupling being accessible for interconnection and disconnection of the valve pin while the enclosure is enclosed. 
     The actuator typically comprises a fluid driven actuator, the chamber of the actuator comprising a fluid sealed chamber, the axial drive device comprising a piston slidably mounted within the fluid sealed chamber. 
     The mounting plate is preferably fixedly mounted to either a fluid delivery manifold or a top clamping plate in an arrangement such that the adjustment screw is rotatable to axially adjust the valve pin to selectable upstream and downstream axial positions. 
     The manifold is typically disposed between the mounting plate and the exit of the fluid delivery channel, the manifold having a fluid distribution channel delivering injection fluid to the fluid delivery channel. 
     The top clamp plate is preferably disposed upstream of the manifold. 
     The actuator is typically mounted for axial movement without rotation. 
     The apparatus preferably further comprises a top clamp plate interconnected to a mold containing a cavity with which the exit of the fluid delivery channel communicates, a heated manifold that delivers heated injection fluid to the fluid delivery channel and an injection molding machine that delivers heated injection fluid to the heated manifold. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and further advantages of the invention may be better understood by referring to the following description in conjunction with the accompanying drawings in which: 
         FIG. 1  is a cross section of a valve that includes an adjustment apparatus according to the invention showing the adjustment screw fixedly mounted to a cooling plate that is fixedly mounted to a fluid distribution manifold. 
         FIG. 2  is a perspective view of mounting plate and adjustment screw according to the invention shown fixedly mounted to a cooling plate via mounting screws having mounting rails, the mounting screws fixedly mounting the adjustment screw to a fluid distribution manifold. 
         FIG. 3  is a perspective view of an actuator housing that can be slidably mounted on the rails shown in  FIG. 2  showing axial apertures provided in the housing that slidably receive the rails. 
         FIG. 4  is a cross-sectional view of the adjustment screw and plate components of the  FIG. 1  system showing the fixed interconnection of the mounting plate to the manifold and the slidable mounting of the actuator housing on the rails. 
         FIG. 5  is a cross-sectional view of certain components of the  FIG. 1  assembly showing the adjustment screw fixedly attached to the actuator housing after adjustment of the screw within the mounting plate and showing in schematic an alternative mounting of the mounting plate to a top clamping plate. 
         FIG. 6A  is a top view of a subassembly of certain components of the  FIG. 1  system showing alternatively available clockwise and counterclockwise means of screwing the adjustment screw. 
         FIG. 6B  is a side view of the components of the subassembly shown in  FIG. 6A  showing the result of clockwise rotation of the adjustment screw. 
         FIG. 6C  is a side view of the components of the subassembly shown in  FIG. 6A  showing the result of counterclockwise rotation of the adjustment screw. 
         FIG. 7  is a perspective view of the subassembly of components of  FIG. 6  showing a final step in use of the mounting plate-adjustment screw where the adjustment screw is fixedly attached to the actuator housing causing the housing to axially slide on the rails to a fixed position determined by the previous step of rotating the adjustment screw within the mounting plate. 
     
    
    
     DETAILED DESCRIPTION 
     As shown in  FIGS. 1-7 , the invention provides an apparatus  10  for adjusting the axial position A of a valve pin  50  in a larger injection molding system that typically includes an injection molding machine  2  that injects molten injection fluid  4  into the distribution channels  65  et al. of a heated distribution manifold or hotrunner  60 . The apparatus  10  includes an actuator  15  comprising a housing  20  having a chamber  15   c  enclosing a piston drive member  40  that is fixedly interconnectable to the valve pin  50 , the drive member  40  driving the valve pin  50  reciprocally upstream and downstream along an axial path of travel A through a fluid delivery channel  63  having an exit or gate  107  to a cavity  110  of a mold  112  which is reciprocally opened and closed by reciprocal downstream and upstream driven movement AA,  FIG. 4 , of a distal downstream tip end  52  of the valve pin  50  into and out of the exit  107  of the fluid delivery channel  63 . The actuator housing  20  is slidably mounted upstream of the fluid delivery channel  63  for controlled upstream and downstream movement AA of the drive member  40  along a path complementary to the axial path of travel A of the valve pin. 
     The apparatus  10  includes a mounting plate  200  and an axial position adjustment screw  300  screwably mounted within the mounting plate  200  upstream of the housing  20  of the actuator  15 , the adjustment screw  300  being controllably screwable clockwise  315  and counterclockwise  317  within the mounting plate  200  to move along an upstream and downstream path A complementary to the axial path of travel A of the drive member  40  and the valve pin  50 . 
     The path of movement or travel of the screw  300  and drive member  40  and actuator  20  can be generally parallel to path of travel A of the valve pin  50 . Or the path of movement or travel of the adjustment screw  300  and drive member  40  can be axially aligned or coincident with the path of axial travel A of the valve pin  50   
     The valve pin  50  is movable to selectable axial starting or ending injection cycle positions along the path of travel A such that the axial position of the tip end  52  of the valve pin  50  is selectively adjustable by selectable rotation  315 ,  317  of the adjustment screw  300 . The selected starting or ending axial position of the valve pin  50  is effected by first clockwise or counterclockwise screwing of the adjustment screw  300  is fixed or set, fixedly interconnecting the actuator  15  or housing  20  to the adjustment screw  300  via locking bolt  400 . Once the axial position of the screw  300  is set, the starting or ending injection cycle position of the valve pin  50  is correspondingly set via the interconnection of the screw  300  to the housing and the mounting of the drive member  40  within the housing  20  and the interconnection of the actuator coupling  40   c  to the proximal upstream disposed pin head  50   h.    
     The drive member  40  is preferably interconnectable to and disconnectable from the valve pin  50 ,  50   h  externally of the enclosure or chamber  15   c  of the housing  20  of the actuator  15  while the enclosure  15   c  is still enclosed not requiring disassembly of the actuator  15  or housing  20  in order to gain access to the mechanism(s) that interconnect the pin  50  to the drive member  40 . 
     The actuator can alternatively comprise an electrically powered motor as described for example in U.S. Pat. No. 6,294,122 that has an electrically or electric power driven rotor that is mounted and housed in an actuator chamber or housing, the rotor being driven to move along an axial path of travel to concomitantly drive a valve pin  50  along an axial path of travel in a fluid delivery channel as described in U.S. Pat. No. 6,294,122, the disclosure of which is incorporated herein by reference in its entirety. 
     The apparatus typically further comprises a coupling  40   c  that interconnects an upstream end  50   h  of the valve pin  50  to the axial drive device  40 , the coupling  40   c  being accessible for interconnection and disconnection of the valve pin head  50   h  with and while the enclosure or chamber  15   c  containing the drive member  40  is still enclosed. 
     The actuator  15  typically comprises a fluid driven actuator, the enclosure  15   c  of the actuator  15  comprising a fluid sealed chamber  15   c , the axial drive device comprising a piston  40  slidably mounted within the fluid sealed chamber  15   c.    
     The mounting plate  200  is typically fixedly mounted to either a fluid delivery manifold or hotrunner  60 ,  FIGS. 1-5 , or to a top clamping plate  800 ,  FIG. 6 , in an arrangement such that the adjustment screw  300  is rotatable  315 ,  317  to axially adjust A the valve pin  50  to selectable upstream and downstream axial positions. 
     The manifold  60  is preferably disposed between the mounting plate  200  and the exit  107  of the fluid delivery channel  63 ,  65 , the manifold  60  having a fluid distribution channel  65  delivering injection fluid to the fluid delivery channel  63 . 
     The top clamp plate  800  is typically disposed upstream of the manifold. 
     The actuator housing  20  is preferably slidably mounted on rails  250  for axial movement A without rotation, the rails preventing the housing  20  from rotating when the screw  300  is screwably rotated  315 ,  317 . 
     The top clamp plate  800  is typically fixedly interconnected to a mold or mold plate(s)  112  containing a cavity  110  with which the exit  107  of the fluid delivery channel communicates. The heated manifold  60  delivers heated injection fluid  4  to the fluid delivery channel  63  and the injection molding machine  2  that delivers heated injection fluid  4  to the heated manifold  60 . 
     As shown in  FIG. 1 , the apparatus  10  is comprised of an actuator  15  that is comprised of a housing  20 , a piston  40  acting as the drive mechanism which is sealably and slidably mounted within a complementary cylindrical chamber  15   c  formed within the housing  20 . The downstream end of the piston  40  is axially fixedly connected to the upstream proximal end  50   h  of the valve pin  50  that has a downstream distal tip end  52  that is reciprocally drivable upstream and downstream along the axis A into and out of a complementarily configured exit port or gate  107  of a downstream portion  105  of the channel formed by a nozzle  62 . The exit port  107  is the downstream terminus of the downstream channel portion  105  formed within the distal end  100  of the nozzle  62  that is axially stationarily mounted to and assembled together with a fluid distribution manifold  60  that has a distribution channel  65  that communicates with and delivers injection fluid under pressure to and downstream through channels  63 ,  105  and eventually through the exit port  107  when the pin  50  and tip end  52  are disposed upstream, the injection fluid flowing out of exit port  107  into mold cavity  110 . 
     As shown in  FIGS. 1, 4  the mounting plate  200  is axially A fixedly interconnected to a downstream mount  80  via bolts  270  that are axially fixedly attached between mounting plate  200  and downstream mount  80 . As shown, a cooling plate  70  is typically fixedly mounted between the actuator housing  20  and the heated manifold  60  and is supported on an upstream surface of the mount  80  that is directly attached to and in engagement with the heated manifold  60 . Bolts  270  fixedly interconnect mounting plate  200  to heated manifold  60  such that the plate  200  is axially fixed relative to the exit or gate  107 . Bolts  270  attach plate  200  to mount  80  via head  273  and screw  275 . The head  273  of bolts  270  are received within complementary receiving attachment recesses  207  and the threaded ends  275  of bolts  270  are received within threaded apertures  85  provided mount  80 . The downstream mounting plate  80  is in turn axially fixedly mounted via bolts or pins  90  to the body of fluid distribution manifold  60 . The manifold  60  is in turn axially fixedly or stationarily mounted onto nozzle  62 ,  100  that is axially stationarily mounted at its downstream distal end within a mold plates  112 . Thus the mounting plate  200  is axially stationarily mounted relative to the exit port  107  of the nozzle  100 , the adjustment screw  300  being selectively adjustable in the axial direction A relative to the exit port  107 . 
     As shown in  FIGS. 1-4, 6A-7 , the actuator housing  20  is axially A slidably mounted on rails  250  that are slidably received within complementary receiving apertures  28  provided within the body of housing  20 . The actuator housing  20  is slidably movable upstream and downstream A along rails  250  in the axial A direction. As shown in  FIG. 4 , rails  250  are coaxially mounted around elongated connecting bolts or screws  270 . 
     As shown in  FIGS. 1-3, 5-7 , the actuator housing  20  is reversibly and readily fixedly connectable to and disconnectable from the adjustment screw  300  via an attachment screw  400  that has male threads  405  that are screwable within female threads  25  provided within the body of housing  20 . When attachment screw  400  is screwed clockwise, housing  20  is pulled upstream U,  FIG. 5 , to a position where the upstream top surface  27  of housing  20  eventually reaches a position where it is in compressed engagement with the downstream surface  311  of adjustment screw  300  thus fixedly connecting housing  20  axially to adjustment screw  300 . When housing  20  is so connected to screw  300 , the screw  300  cannot be rotated because housing  20  is rotationally fixed by virtue of its mounting on rails  250 . 
     Once screw  300  is axially set by selective screwing  315 ,  317  using spanner wrench S, and housing  20  is next subsequently axially fixedly interconnected to screw  300  via screw  400  or other means, the starting and/or ending axial position of the tip end  107  of valve pin  50  is fixed for future injection cycles. The starting or ending axial injection cycle position of all of housing  20 , drive member  40 , valve pin  50  and the tip end  107  of the valve pin  50  are all so fixed. 
     Housing  20  can be disconnected from screw  300  by conversely unscrewing attachment screw  400  in a counterclockwise direction thus loosening housing  20  from compressed engagement with adjustment screw  400  and screw  300 . When housing  20  is so loosened, screw  300  can be rotated or screwed via spanner screw S has teeth T that are insertable into complementary receiving apertures disposed in the upstream surface of screw  300  enabling screw  300  to be manually rotated to a selectable degree of clockwise rotation  315 ,  FIG. 6A, 6B  or to a selected degree of counterclockwise rotation  317 ,  FIGS. 6A, 6C . When screw  300  is rotated to a selected degree  315  or  317 , screw  300  is in turn moved axially  300 A by a corresponding selected degree of axial travel. 
     Depending on the selected degree  300 A of clockwise  315  or counterclockwise  317  rotation of screw  300 ,  FIGS. 6A, 6B, 6C, 7 , the axial position of screw  300  can be adjusted a selected axial distance in a downstream D or upstream U direction. Because the valve pin  50  is fixedly interconnected to the drive mechanism  40  which is, in turn, axially fixed within housing  20  during the initial pin positioning process (the housing  20  is, in turn, axially fixed to screw  300  by use of attachment screw  400 , the tip end  52  of the valve pin  50  can thus be axially adjusted to a selected axial position relative to the exit port  107 , the exit  107  being stationary relative to the mounting plate  200  in which adjustment screw  300  is mounted. 
       FIGS. 1-4  show an embodiment where the mounting plate  200  is fixedly or stationarily mounted to the manifold  60  which is in turn fixedly or stationarily mounted axially relative to the nozzle  100  and exit  107 . Axial adjustment of adjustment screw  300  in upstream direction U,  FIG. 6C , or adjustment of screw  300  in a downstream direction D,  FIG. 6B , therefore results in a concomitant axial movement of the actuator housing  20 , piston  40  and its interconnected valve pin  50  and its tip end  52  relative to exit  107  such that the tip end  52  can be positioned at selected axial positions within exit  107  at the beginning or end of an injection cycle. 
     The beginning or ending axial position of the valve pin  50  and its tip end  107  are typically stationary positions, the purpose of the assembly  200 ,  250 ,  300  being to enable the user to select and predetermine the precise axial location of the beginning or end axial positions as well as to change and adjust such beginning and end positions prior to beginning an injection cycle. Thus the user can predetermine before the injection cycle is started where the beginning stationary start position and the ending stationary end position of the tip end  107  is going to be. 
     Such selective axial positioning of the tip end  52  at the beginning of an injection cycle thus enables the user to adjust, modify, improve or change the size, shape or appearance of vestiges that may appear in or on the surface of a cooled molded part that may be formed within cavity  110  at or around the location of the exit  107  as a result of the precise positioning of the tip end  52  relative to the exit  107  when the pin  100  is in its fully downstream exit closed position. And such selective axial positioning of the tip end  52  enables the user to readily adapt the valve pin to axially fit varying axial lengths of nozzles, manifolds, actuators and other components of the system of varying sizes and configurations. 
       FIG. 5  shows an alternative embodiment where the mounting plate  200  is fixedly or stationarily mounted  805  on or to a top clamping plate  800  that is disposed upstream of the manifold  60 . In such an embodiment, the coupling  40   c  preferably is adapted to allow the pin head  50   h  to travel radially R within but at the same time remain axially coupled to the coupling  40   c . A coupling  40   c  and pin head  50   h  design as shown and described in U.S. Pat. No. 8,091,202 (the disclosure of which is incorporated herein by reference in its entirety), particularly with reference to  FIGS. 2 a , 2 b , 3 a , 3 b    therein can provide a radial travel clearance for the  FIG. 5  embodiment that enables the pin  50 ,  50   h  to travel radially R a small distance within the coupling  40   c  that occurs on heating of the manifold  60 . Such radial clearance is needed because the actuator support components  200 ,  250 ,  300  for the actuator  15 ,  20 ,  40  are radially fixed relative to the manifold which is not radially fixed but rather moves and expands slightly in the radial direction on heating. Thus on heating of the manifold  60  the pin head  50   h  will travel radially R a small distance together with the manifold relative to the radially fixed coupling  40   c . The radial clearance provided by the coupling design described in U.S. Pat. No. 8,091,202 thus allows the pin  50   h  to travel radially and simultaneously remain axially coupled within coupling  40   c.    
     In such an embodiment the top clamping plate  800  is, in turn, stationarily mounted axially relative to the nozzle  100  and the nozzle exit or exit port  107 , such that axial adjustment of adjustment screw  300  in upstream direction U,  FIG. 6C , or adjustment of screw  300  in a downstream direction D,  FIG. 6B , results in a concomitant axial movement of the actuator housing  20 , piston  40  and its interconnected valve pin  50  and its tip end  52  relative to axially stationary mounting plate  200 . Again, such selective axial positioning of the tip end  52  at the beginning of an injection cycle enables the user to adjust, modify, improve or change the size, shape or appearance of vestiges that may appear in or on the surface of a cooled molded part that may be formed within cavity  110  at or around the location of the exit  107 . And such selective axial positioning of the tip end  52  enables the user to readily adapt the valve pin to axially fit varying axial lengths of nozzles, manifolds, actuators and other components of the system of varying sizes and configurations.