Abstract:
A module or unit manufactured allowing simplified installation of a lifter rod assembly of a core lifter apparatus for a mold for molding plastic parts. In some embodiments, a slide is movably mounted with respect to a retainer and/or a gib, so that the retainer attached to the lifter rod can be moved in a linear direction and a rotational direction to provide free motion and reduce wear and breakage due to uneven ejector plate movement during production cycling of the mold. In some embodiments, the slide has one or more spring-loaded devices that hold the retainer in a particular position with respect to the slide, positioned to receive the lifter rod during mold assembly. In some embodiments, the retainer accommodates connections and coiled hoses for delivering cooling fluid to an internally cooled lifter rod.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0001]    This invention relates to a module or unit for mounting a lifter rod or blade to mold and release molded undercuts. 
       Discussion of Related Art 
       [0002]    Conventional internal core lifter devices include lifter rods that are internally cooled with coolant that flows through channels formed within the lifter rods. 
         [0003]    Known internal core lifter devices include an internal core blade having one end cooperating with mold surfaces for molding and ejecting plastic parts, and having an opposite end pivotally mounted at a predetermined molding angle, in a range of angles, of the mold apparatus. It is known to pivotally mount the opposite end of the core blade for pivoting about multiple axes and also to provide a support for mounting a coupling to the mold apparatus to move the one end of the core blade as the mold apparatus operates mold halves between open and closed positions. It is also known for the core blade to pivot about the coupling in a plane aligned with a linear travel of the lower end of the core blade along the support, and if transverse loads are applied to the core blade it is known that the core blade can also pivot in a second plane, at an angle to the first plane, to prevent binding of the core blade and coupling relative to the support. 
         [0004]    Starkey, U.S. Pat. Nos. 5,137,442 and 5,316,467 each teaches internal core lifter apparatuses, with multiple axes compensation features. The entire teachings and disclosure of each of Starkey, U.S. Pat. Nos. 5,137,442 and 5,316,467, and any related United States Patent and/or Patent Application is incorporated by reference into this specification. 
       SUMMARY OF THE INVENTION 
       [0005]    The apparatus and method of this invention can be manufactured and marketed as a module or unit that can be easily installed, repaired and/or replaced, particularly by one user or person versus two required at each the front and the back of the mold during assembly. 
         [0006]    In some embodiments of this invention, a retainer is movably mounted with respect to an ejector plate so that the retainer to which a lifter rod is attached can move in a linear direction as well as a rotational direction. The linear and rotational movement allow the lifter rod to move with relatively free motion to compensate for any uneven movement by the ejector plate, for example, and thus prevent breakage in the mold and also extend the life of corresponding mold elements. 
         [0007]    According to some embodiments of this invention, one spring loaded device is used to hold a core rod retainer in a specific position at a predetermined set angle. In other embodiments of this invention, another spring loaded device is used to hold the position of the core rod retainer during assembly to the location it will later be in when the ejector plates are retracted and the mold is closed during injection. The securing of both the retainer angle and the retainer&#39;s location, readies the entire unit for receiving the lifter rod during mold assembly, versus one person loading the rod and a second person moving and adjusting the retainer&#39;s location. 
         [0008]    In some embodiments of this invention, the retainer has hoses attached to the retainer body to supply fluid, such as cooling fluid, to an internally cooled lifter rod. In some embodiments of this invention, the hoses are coiled hoses and are able to change length as a mold&#39;s ejector plates move forward and back and the retainer travels perpendicular. 
         [0009]    Other features and advantages of this invention will be apparent from the following detailed description taken in conjunction with the following Figures, wherein like reference numerals represent like features. 
     
    
     
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
         [0010]      FIG. 1  shows a perspective view of a module or unit of a core lifter apparatus, in the back position when a mold&#39;s ejector plates are retracted during the mold closed/injection stage of the cycle, according to one embodiment of this invention; 
           [0011]      FIG. 2  shows a perspective view of a module or unit of a core lifter apparatus, in a front position after molded part ejection, according to one embodiment of this invention; 
           [0012]      FIG. 3  shows a perspective view of the module or unit shown in  FIG. 2 , but in the back position; 
           [0013]      FIG. 4  shows a perspective view of a module or unit of a core lifter apparatus, shown in an example of a locked position at 5°, according to one embodiment of this invention; 
           [0014]      FIG. 5  shows a perspective view of the module or unit shown in  FIG. 4 , but in an example of a locked position at 45°; 
           [0015]      FIG. 6  shows a perspective enlarged sectioned view of a detent within the core rod retainer set at 15 degrees, and also shown are etched line indicators of the 15 degree position for the mold assembly person&#39;s viewability, according to one embodiment of this invention; 
           [0016]      FIG. 7  shows a perspective view of a module or unit of a core lifter apparatus mounted in an ejector plate after the angle has been set and secured, and in the back position, according to one embodiment of this invention; 
           [0017]      FIG. 8  shows a sectional view of a core lifter apparatus, in the back position, according to one embodiment of this invention; 
           [0018]      FIGS. 9-11  each shows a sectional view of a retainer, a slide and a gib, each in different relative positions reflecting the unevenness that occurs during the cycling of the mold, according to one embodiment of this invention; 
           [0019]      FIG. 12  shows a sectional view of a retainer, a slide and a gib, all mounted within an ejector plate, with the gib shown shifted within the ejector plate pocket to automatically adjust for the unevenness that occurs during the cycling of the mold, according to one embodiment of this invention; 
           [0020]      FIG. 13  shows a perspective view of a portion of a retainer and attached cooling fluid lines, according to one embodiment of this invention; 
           [0021]      FIG. 14  shows a sectional view of a core lifter apparatus and its spacer for final tuning of the position within the mold, according to one embodiment of this invention; 
           [0022]      FIG. 15  shows a sectional view of a portion of a core lifter apparatus, according to one embodiment of this invention; and 
           [0023]      FIG. 16  shows a sectional view of a portion of a core lifter apparatus, according to one embodiment of this invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]      FIG. 1  shows a module or unit of core lifter apparatus  22  which is often manufactured for in ejector plate  24 , such as shown in  FIG. 7 .  FIG. 8  shows the module and how it is positioned with respect to pin plate  23 , ejector plate  24  and clamp plate  25 , in some embodiments of this invention. 
         [0025]    During use, for example,  FIGS. 2 and 3  show lifter rod  45  operating between forward or front position  46 , such as shown in  FIG. 2 , and back or rear position  47 , such as shown in  FIG. 3 . In some embodiments of this invention, as lifter rod  45  moves with respect to ejector plate  24 , for example, the module of this invention swivels, slides and/or otherwise moves to accommodate and/or compensate for any uneven movement of ejector plate  24  and/or any other related element or corresponding part. In some embodiments of this invention, the module and/or lifter rod  45  moves with a higher degree of freedom of motion and thus reduces mechanical wear and/or breakage of mold pieces. 
         [0026]      FIGS. 1-5  show different arrangements of retainer  40  mounted between two slides  35 , according to different embodiments of this invention. In other embodiments of this invention, retainer  40  can be mounted to only one slide  35  or can be mounted to more than two slides  35 . As shown in  FIGS. 1-5 , one retainer  40 , which can also be referred to as a trunnion, a trunnion base, a block, a retainer block and/or any other suitable element, is formed by one unitary or integrated element but other embodiments can have retainer  40  formed by more than one element or piece. In some embodiments of this invention, retainer  40  comprises inlet  41  and outlet  43  for passing a cooling fluid, for example, and also has a suitable through hole, threaded or non-threaded, or other void to accommodate attachment of lifter rod  45 . 
         [0027]    In some embodiments according to this invention, gib  30  is mounted, secured and/or otherwise attached directly to or indirectly with respect to ejector plate  24 , such as shown in  FIG. 7 . Also as shown in  FIG. 7 , according to some embodiments of this invention, gib  30  is further secured and/or mounted to ejector plate  24  with a top gib holding the unit to ejector plate  24  yet allowing it to laterally shift to compensate for any uneven movement of ejector plate  24 .  FIG. 8  shows a sectional view of core lifter apparatus  22  in the back position according to some embodiments of this invention. 
         [0028]      FIGS. 4 and 5  show slides  35  able to move in linear direction  27  and/or rotational direction  28 . A combination of linear and rotational movement of retainer  40  with respect to gib  30  and/or ejector plate  24 , for example, allows retainer  40  to float and/or center itself within ejector plate  24 . This movement can reduce or eliminate premature wear or product failure caused by interferences and stresses ultimately applied to lifter rod  45 , for example, that are caused by misalignment of ejector plate  24 .  FIGS. 9-11  illustrate how retainer  40  can become misaligned with respect to ejector plate  24 , for example, and how slides  35  of this invention can be used to move retainer  40  and thus rod  45  in linear direction  27  and rotational direction  28  to overcome reduced lifespans of retainer  40 , lifter rod  45  and/or other connected elements. 
         [0029]      FIGS. 4 and 5  show features of some embodiments of this invention in which gib  30  has inner surface  31  contacting outer surface  36  of slide  35 . In some embodiments of this invention, inner surface  31  is concave and/or arcuate. In some embodiments of this invention, outer surface  36  is convex and/or arcuate. In other embodiments of this invention, inner surface  31  and/or outer surface  36  can have any other suitable shapes and/or dimensions that allow slide  35  and thus retainer  40  to move in linear direction  27  and/or rotational direction  28 . As slide  35  moves with respect to gib  30 , attached retainer  40  can have only linear movement, can have only rotational movement, or can have linear movement and rotational movement. As used throughout this specification and in the claims, the term linear movement is intended to relate to the movement in the direction of linear direction  27  as shown in  FIGS. 4, 5 and 9-12 , and, the term rotational movement is intended to relate to the movement in the direction of rotational, direction  28  as shown in  FIGS. 4, 5  and  9 - 12 , and any other suitable term can be used in place of or in addition to the term linear movement and/or the term rotational movement. In some embodiments of this invention, inner surface  31  slidingly and/or rotatably engages with outer surface  36  to move lifter rod  45  in linear direction  27 , rotational direction  28  and/or any other suitable direction. 
         [0030]    In some embodiments of this invention, slide  35  and retainer  40  move together between front position  46  and rear position  47 , such as shown between  FIGS. 2 and 3 . According to some embodiments of this invention, lock  70  can be adjustable, lockable and/or releasable to releasably hold retainer  40  in rear position  47 . Locking retainer  40  in rear position  47  positions the unit for accepting lifter rod  45  during installation when connecting retainer  40  with lifter rod  45 . With such embodiments of this invention, it is possible for a maintenance person or user to change or replace lifter rod  45  without a need for the help of a second person moving retainer  40  to find the location of the incoming lifter rod  45 . For example, this feature of this invention can eliminate the need for a second person to be positioned beneath the mold because retainer  40  itself holds lifter rod  45 , particularly at rear position  47 . 
         [0031]    Depending on the particular mold design, lifter rod  45  can be set at a different angle or angular position, with respect to slide  35  and/or ejector plate  24 , for example. Some embodiments of the module of this invention can accommodate lifter rod  45  mounted or secured in different relative positions, such as one or more angular positions.  FIGS. 4 and 5  show one embodiment of the module according to this invention which can accommodate different set positions. 
         [0032]      FIG. 4  shows retainer  40  positioned at a 5° angle with respect to slide  35  and/or ejector plate  24 .  FIG. 5  shows retainer  40  positioned at a 45° angle with respect to slide  35  and/or ejector plate  24 .  FIG. 6  shows an enlarged view of retainer  40  attached to two slides  35 .  FIG. 6  shows retainer  40  having pivot rod  48  matingly engageable with opening  37  of slide  35  which allows retainer  40  to pivot and/or otherwise move with respect to slide  35 , according to some embodiments of this invention. In other embodiments of this invention, retainer  40  and/or slide  35  can have any other suitable connector and/or feature that allows retainer  40  to pivot and/or otherwise move with respect to one or more slides  35 . 
         [0033]    As shown in  FIGS. 4-6 , retainer  40  has markings to identify different set positions of retainer  40  with respect to slide  35 .  FIG. 6  shows the markings having 5° increments but other embodiments of this invention can have different increment sizes, shapes and/or features.  FIG. 5  shows outer surface  36  of slide  35  having 5° increment markings and stop positions but other embodiments of this invention can have different increment sizes, shapes and/or features. 
         [0034]      FIG. 6  shows positioning device  65  engageable to fix or secure a relative position of retainer  40  with respect to slide  35 . In some embodiments of this invention, adjustable lock  60  comprises positioning device  65  that can be engaged and/or adjusted to engage bias element  62  which can have enough bias force to move plunger  63  into a corresponding receiver  64  and thus securely or fixedly hold the position of retainer  40  with respect to slide  35 . The arrow representing adjustable lock  70 , in  FIG. 6 , shows the location of adjustable lock  70 , and in some embodiments of this invention, adjustable lock  70  can have a structure and function similar to or the same as the structure of adjustable lock  60 . In some embodiments of this invention, bias element  62  comprises a coiled spring, such as shown in  FIG. 6 , but in other embodiments can also comprise any other suitable spring or other element that exerts a large enough force to hold the position of retainer  40  with respect to slide  35 . In some embodiments of this invention, plunger  63  comprises a ball, a post and/or any other suitable element that can engage with receiver  64  and hold retainer  40 . In some embodiments of this invention, receiver  64  comprises retainer  40  having one or more voids that correspond to or cooperates with plunger  63 , for example, to hold the position of retainer  40  with respect to slide  35 . 
         [0035]    In some embodiments of this invention, such as shown in  FIGS. 4 and 13 , for example, retainer  40  comprises inlet  41  in communication with fluid, such as cooling fluid, furnished from cooling fluid supply  55  through cooling fluid supply line  56 , and with supply channel  42 , such as shown in  FIGS. 14 and 15 . Retainer  40  comprises outlet  43  in communication with fluid, such as cooling fluid, returned to cooling fluid return  57  through cooling fluid return line  58 , and with return channel  44 , such as shown in  FIGS. 14 and 15 . In some embodiments of this invention, retainer  40  and lifter rod  45  each forms or comprises supply channel  42  and/or return channel  44 . Supply channel  42  and/or return channel  44  can be formed by any other suitable hose, line and/or structure. 
         [0036]      FIGS. 13-15  show some embodiments of this invention in which cooling fluid supply  55  comprises a coiled cooling fluid supply line  56  and cooling fluid return  57  comprises a coiled cooling fluid return line  58 . The coiled cooling fluid lines are flexible and particularly suitable for the spaces defined by ejector plate  24 , such as shown in  FIGS. 13-15 , because retainer  40  moves between front position  46  and rear position  47 , and during movement the coiled hoses or lines stay out of the way of other moving parts. In some embodiments of this invention, cooling fluid supply line  56  connects and forms communication with inlet  41  of retainer  40  and cooling fluid return line  58  connects and forms communication with outlet  43  of retainer  40 . Any suitable mechanical and/or fluidic connection can be used to connect and form communication with inlet  41  and/or outlet  43 .