Patent Publication Number: US-2023137786-A1

Title: Mold extractor

Description:
STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH OR DEVELOPMENT 
     This invention was made with Government support under Contract No.: DE-NA0002839 awarded by the United States Department of Energy/National Nuclear Security Administration. The Government has certain rights in the invention. 
    
    
     BACKGROUND 
     Various industrial components are manufactured using a variety of molding processes. In a compression molding process, a component is manufactured by flowing a heated or molten plastic, metallic, or similar material in a mold cavity of a first mold portion and covering the molten material with a second mold portion. Pressure and/or heat is applied to one or both of the mold portions to force the heated material into contact with all mold surfaces. The pressure and/or heat are maintained until the molten material has cured, at which point the mold portions are separated and the component is extracted. 
     Depending on the specific geometry of the component being molded, one or more of the mold portions may become stuck or sealed to the component after the component cures. In some instances, this is because the pressure applied during the mold process may form a vacuum seal between a mold portion and the pressed part. This vacuum seal may be difficult to unseat, and in some cases may lead to damage of the component or the mold portion when removing the component from the mold. There thus remains a need for a way to effectively and safely remove a component from a mold portion following a compression molding process or similar manufacturing process. 
     BRIEF SUMMARY 
     Embodiments of the disclosure are directed to a mold extractor that can be implemented to remove a mold portion safely and easily from a molded part after a compression molding process or similar, and methods of using such a mold extractor. At a high level, the mold extractor may include a retainer that abuts and secures the molded part in place and that is operatively coupled to a mold holder via an extraction rod or similar. The mold holder may be configured to removably couple to the mold portion and move with respect to the retainer to thereby unseat the mold portion from the molded part without damage to the part. 
     For example, some embodiments are directed to a mold extractor for separating a molded part from a mold portion following a molding process. The mold extractor comprises a mold holder configured to removably couple to the mold portion, a retainer configured to abut a portion of the molded part, the retainer substantially surrounding the mold holder such that a cavity is provided between the mold holder and the retainer, and an extraction rod engaged with the mold holder and the retainer and spanning the cavity between the mold holder and the retainer. The mold extractor is configured to reduce a distance between the mold holder and the retainer along the extraction rod such that the mold holder translates into the cavity and imparts a force on the mold portion sufficient to extract the mold portion from the molded part. 
     Other embodiments are directed to a method of separating a molded part from a mold portion following a molding process. The method comprises engaging the mold portion with a mold holder, placing a retainer around the mold holder such that it substantially surrounds the mold holder and abuts a portion of the molded part, the placing the retainer around the mold holder including extending an extraction rod between the mold holder and the retainer such that the extraction rod spans a cavity between the retainer and the mold holder, and reducing a distance between the mold holder and the retainer along the extraction rod such that the mold holder translates into the cavity and imparts a force on the mold portion sufficient to extract the mold portion from the molded part. 
     These and other features will be discussed in more detail below in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the disclosure are described in detail below with reference to the attached drawing figures, wherein: 
         FIG.  1    is a perspective view of a pressed part coupled to a mold portion following a compression molding process or similar; 
         FIG.  2    is a perspective view of the pressed part and the mold portion shown in  FIG.  1   , but separated following an extraction process according to some embodiments of the disclosure; 
         FIG.  3    is a perspective view of the pressed part and the mold portion shown in  FIG.  1    with a mold extractor coupled thereto according to some embodiments of the disclosure; 
         FIG.  4    is a perspective view of a pressed part retainer of the mold extractor shown in  FIG.  3   ; 
         FIG.  5    is a perspective view the pressed part and the mold portion with the mold extractor coupled thereto as shown in  FIG.  3   , but with the pressed part retainer shown in  FIG.  4    removed in order to illustrate the internal components of the mold extractor; 
         FIG.  6    is a top view of the pressed part and the mold portion with the mold extractor coupled thereto shown in  FIG.  3   ; 
         FIG.  7    is a first cross-sectional view of the pressed part and the mold portion with the mold extractor coupled thereto as viewed along line  7 - 7  in  FIG.  6   ; 
         FIG.  8    is a second cross-sectional view of the pressed part and the mold portion with the mold extractor coupled thereto as viewed along line  8 - 8  in  FIG.  6   ; and 
         FIGS.  9 A- 9 F  schematically show various steps used to extract the mold portion from the pressed part using the mold extractor shown in  FIGS.  3 - 8   . 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description references the accompanying drawings that illustrate specific embodiments of the disclosure. The embodiments are intended to describe aspects of the disclosure in sufficient detail to enable those skilled in the art to practice the various embodiments. Other embodiments can be utilized, and changes can be made without departing from the scope of the disclosure. The following detailed description is, therefore, not to be taken in a limiting sense. The scope of the current invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled. 
     In this description, references to “one embodiment,” “an embodiment,” or “embodiments” mean that the feature or features being referred to are included in at least one embodiment of the technology. Separate references to “one embodiment,” “an embodiment,” or “embodiments” in this description do not necessarily refer to the same embodiment and are also not mutually exclusive unless so stated and/or except as will be readily apparent to those skilled in the art from the description. For example, a feature, structure, act, etc., described in one embodiment may also be included in other embodiments, but is not necessarily included. Thus, the current technology can include a variety of combinations and/or integrations of the embodiments described herein. 
     Generally, aspects of the disclosure are directed to mold extractor for removing a mold portion from a component following a molding process of the component. The mold extractor may be particularly useful for compression molding processes, in which a portion of the mold can become vacuum sealed to the pressed part, thereby making it difficult to separate the mold portion from the pressed part without damaging the part. However, embodiments are not limited to use in connection with compression molding processes and can be implemented in any process in which a mold or similar needs to be extracted from a component during a manufacturing process. 
     In some embodiments, the mold extractor may include a pressed part retainer operatively coupled to a mold holder via an extraction rod or similar. During use, the pressed part retainer is configured to hold the pressed part in place while the mold holder, which engages the mold portion, moves closer to the retainer, thereby imparting a force on the mold portion, unseating the vacuum seal, and pulling the mold portion apart from the pressed part. The mold extractor thereby easily and quickly removes the mold portion with little chance of damaging the pressed part or the mold portion. These and other features will become more apparent in connection with the description of the various figures. 
     First,  FIGS.  1  and  2    show a pressed part  100  and a mold portion  102 , with  FIG.  1    showing the pressed part  100  coupled to the mold portion  102  following a compression molding process or similar, and  FIG.  2    showing the pressed part  100  separated from the mold portion  102  following an extraction process described below. In this embodiment, the pressed portion  102  generally includes a frustoconical shell portion  101  (i.e., a portion that is generally frustoconically shaped but hollow) and an annular portion  103 . However, embodiments of the disclosure are not so limited, and the mold extractor and mold extraction processes described herein could be used with a variety of alternatively shaped pressed parts. 
     To form the pressed part  100  using a compression molding process or similar, a first, or bottom, mold portion (not shown) will be provided having a cavity mirroring the outer contour of the pressed part  100 . The cavity will be filled with heated and/or molten material, such as a flowable plastic or metallic material, and then the second, or top, mold portion  102  will be moved towards the first mold portion, pressing the molding material therebetween. As best seen in  FIG.  2   , the mold portion  102  has an outer contour mirroring the inner contour of the pressed part  100 , thereby forming the hollow interior of the pressed part  100  during the molding process. More particularly, the mold portion  102  includes a frustoconical portion  105  and a cylindrical portion  107 , which will form the inner contours of the frustoconical shell portion  101  and the annular portion  103 , respectively. 
     The mold portion  102  may include other features such as, e.g., an engagement portion  106  having a receiving hole  108  along a central axis thereof. The engagement portion  106  and/or the receiving hole  108  may be used for attaching the mold portion  102  to a molding apparatus (not shown), and/or, as will be more fully discussed, for coupling the mold portion  102  to a mold extractor  110  following the molding process. Again, embodiments of the disclosure could be implemented in connection with alternatively shaped pressed parts, and thus in other embodiments the mold portion  102  will be similarly alternatively sized and shaped without departing from the scope of the disclosure. The mold portion  102  can be constructed from any suitable material and, in one non-limiting example, is constructed from graphite for use in high temperature applications. 
     Due to the geometry of the generally frustoconical pressed part  100 , following the compression molding or similar process the bottom mold portion may easily separate from the outer surface of the pressed part  100 , however the top mold portion  102  may be more difficult to remove. That is, because the top mold portion  102  is received within the hollow interior of the pressed part  100 , the mold portion  102  and the pressed part  100  may form a vacuum-like seal during the molding process. Thus, the pressed part  100  and the mold portion  102  may become stuck in the orientation shown in  FIG.  1   . Embodiments of the disclosure are directed to a mold extractor  110  and a process of using such an extractor  110  that can easily and safely unseat the vacuum-like seal, thereby separating the pressed part  100  from the mold portion  102 , as shown in  FIG.  2   . For example, in embodiments in which the mold portion  102  is constructed from graphite, the mold portion  102  may be relatively brittle. The mold extractor  110  described herein can thus properly support the mold portion  102  to reduce the likelihood of cracking or otherwise damaging the mold portion  102  during an extraction process. 
       FIGS.  3 - 8    show various views of the mold extractor  110  and portions thereof according to embodiments of the disclosure. At a high level, the mold extractor  110  includes a pressed part retainer  112  generally surrounding, but separated from, a mold holder  114 . The pressed part retainer  112  is best seen in  FIGS.  3  and  4   , while the mold holder  114  can be seen in  FIG.  5   , in which the pressed part retainer  112  is removed for clarity. The pressed part retainer  112  is operatively coupled to the mold holder  114  via an extraction rod  116 , which, in the depicted embodiment, is a threaded rod. More particularly, and as best seen in the cross-sectional views shown in  FIGS.  7  and  8   , the extraction rod  116  extends between the pressed part retainer  112  and the mold holder  114  and is received within a through hole  118 ,  120  of each, respectively. 
     The pressed part retainer  112  has a generally frustoconical shell shaped configuration, with a rim  138  thereof having approximately the same size and cross-sectional shape as the annular portion  103  of the pressed part  100 . The pressed part retainer  112  can be constructed from any suitable material and, in some embodiments, is constructed from a plastic or metallic material. Moreover, the pressed part retainer  112  can be constructed using any suitable means and, in some embodiments, the pressed part retainer  112  is constructed using additive manufacturing or a similar process. For example, in some embodiments the pressed part retainer  112  is  3 D printed and made of acrylonitrile butadiene styrene (ABS). 
     In some embodiments, the pressed part retainer  112  may include a seal such as a plurality of O-rings  140  or similar seated in a corresponding plurality of circumferentially extending slots provided in the rim  138 . As will be discussed more fully below, the O-rings  140  will face the pressed part  100  and abut the annular portion  103  thereof during the extraction process in a cushioning manner. The O-rings  140  may be any desired material and in some embodiments may be a pliable material such as rubber or similar in order to provide a layer of cushioning between the rim  138  and the annular portion  103  to reduce the likelihood of damage to the pressed part  100  during the extraction process. 
     The pressed part retainer  112  may further include one or more cutouts  142  extending through the outer shell of the retainer  112 . For example, in the depicted embodiment the pressed part retainer  112  includes three cutouts  142  spaced equidistantly from each other in the circumferential direction, but in other embodiments the pressed part retainer  112  may include more or less cutouts  142  without departing from the scope of the disclosure. For example, in other embodiments the pressed part retainer  112  could include none, one, two, four, or more than four cutouts  142 . When equipped, the cutouts  142  beneficially reduce the amount of material needed to manufacture the pressed part retainer  112  and also provide one or more windows in order to view the mold holder  114  and other internal portions of the mold extractor  110  during use. 
     As best seen in  FIG.  5   , the mold holder  114  generally includes a plurality of legs  144  (in the depicted embodiment, three, although more or less could be employed without departing from the scope of the disclosure) extending generally outward and downward from a substantially cylindrical main body  145 . The mold holder  114  may further include an opening  146  provided generally between neighboring ones of the legs  144 . The opening  146  is sized and shaped to receive, laterally (i.e., a direction substantially perpendicular to the central axis of the through hole  120  provided in the mold holder  114 ) a part of the mold portion  102 . More particularly, in the depicted embodiment the opening  146  is sized and shaped such that the mold holder  114  can slide, laterally, onto the engagement portion  106  of the mold portion  102 . Each leg  144 , in turn, may include one or more protrusions  148  at a distal, inner side thereof, which removably couple the mold holder  114  to the mold portion  102 . More particularly, each protrusion  148  fits underneath a lip of the engagement portion  106  and thus engages the engagement portion  106  during use, which will be more fully discussed below. As with the pressed part retainer  112 , the mold holder  114  can be constructed from any suitable material and, in some embodiments, is constructed from a plastic or metallic material. Moreover, the mold portion  114  can be constructed using any suitable means and, in some embodiments, the mold portion  114  is constructed using additive manufacturing or a similar process. For example, in some embodiments the mold holder  114  is  3 D printed and made of ABS. 
     In some embodiments, the mold extractor  110  may include one or more reinforcing members, particularly when the portions thereof are constructed from a non-metallic material such as ABS or similar. In one non-limiting example, the mold extractor  110  may include a plurality of washers  122 ,  124 ,  126 , and  128  placed along a central axis thereof to provide reinforcement to the various components such as the pressed part retainer  112  and the mold holder  114  during use. More particularly, the pressed part retainer  112  may include a first washer  122  surrounding a top opening of the retainer through hole  118  and a second washer  124  surrounding a bottom opening of the retainer through hole  118 . The mold holder may include a third washer  126  surrounding a top opening of the mold holder through hole  120 , and a fourth washer  128  surrounding a bottom opening of the mold holder through hole  120 . 
     The washers  122 ,  124 ,  126 ,  128  may be held in place using any desired means such as by an adhesive or otherwise. In one non-limiting example, portions of the mold extractor  110  include a recess, trough, slot, or similar cutout sized and shaped to frictionally receive a reinforcing member such as one of the washers  122 ,  124 ,  126 ,  128  therein. Namely, the pressed part retainer includes a first recess  123  and a second recess  125  configured to receive the first washer  122  and the second washer  124 , respectively. The mold holder  114  includes the third recess  127  and a slot  129  configured to receive the third washer  126  and the fourth washer  128 , respectively. The washers  122 ,  124 ,  126 ,  128  may be secured in the respective recess  123 ,  125 ,  127  and/or slot  129  using any desired means. In one non-limiting example, the first, second, and third recesses  123 ,  125 ,  127  and the slot  129  are configured to have a clearance fit with the first, second, third, and fourth washers  122 ,  124 ,  126 ,  128  respectively, such that the washers  122 ,  124 ,  126 ,  128  are pressed into the respective recesses  123 ,  125 ,  127  or slot  129  and frictionally held therein. 
     Finally, the mold extractor includes a plurality of extraction rod engagement members used to move the mold holder  114  towards the pressed part retainer  112  during an extraction process, thereby imparting a force on the mold portion  102  and thus dislodging it from the pressed part  100 . For example, in embodiments in which the extraction rod  116  is a threaded rod or similar, the extraction rod engagement members may be a plurality of nuts tapped and threaded such that they can be threaded onto the extraction rod  116 . In one non-limiting example, the mold extractor  110  may include one or more tightening nuts  130 , one or more extraction nuts  132 , and one or more locking nuts  136 . The tightening nut  130  is disposed within the mold holder  114  and, more particularly, within a corresponding shaped channel, recess, or similar configured to hold the tightening nut  130  securely in place during use. The extraction nut  132  is threaded onto the extraction rod  116  above the pressed part retainer  112  and snugly to a top surface thereof. Optionally, an additional reinforcement member such as an oversized washer  134  or similar may be placed between the extraction nut  132  and the pressed part retainer to absorb some of the force imparted on the mold extractor  110  during use and thus reduce the change of cracking or premature failure. Finally, the locking nuts  136  are threaded onto the extraction rod  116  above the extraction nut  132  and are used to hold the extraction rod  116  in place (i.e., keep the rod  116  from rotating) during use. 
     When oriented in this manner, the mold portion  102  can be extracted from the pressed part  100  simply by tightening, with respect to one another (i.e., moving closer to one another), the tightening nut  130  and the extraction nut  132 . Doing so reduces the span of the extraction rod  116  that extends between the two nuts  130 ,  132  thereby pulling the pressed part retainer  112  and mold holder  114  towards one another. However, because the pressed part retainer  112  is braced and anchored against the pressed part  100  via engagement of the rim  138  (and, when equipped, the O-rings  140  or other seal) against the annular portion  103  of the pressed part and thus itself cannot translate, the mold holder  114  translates along the extraction rod  116  as the span between the tightening nut  130  and the extraction nut  132  is reduced. The mold holder  114 , in turn, imparts a pulling force on the mold portion  102  via the engagement of the molder holder  114  with the engagement portion  106  of the mold portion  102 , and, more particularly, via the engagement of the protrusions  148  of the legs  144  of the mold holder  114  with the lip of the engagement portion  106 . This upward, or pulling, force unseats the vacuum seal formed between the mold portion  102  and the pressed part  100  during the molding process and pops the mold portion  102  free from the pressed part  100 , as shown in  FIG.  2   . Use of the mold extractor  110  in this way reduces the chance that the pressed part  100  or mold portion  102  will become damaged during the extraction process. 
     The process of extracting the mold portion  102  using the mold extractor  110  will be more readily understood with reference to  FIGS.  9 A- 9 F , which shows the various steps used to place the mold extractor  110  on the mold portion  102  and extract the mold portion  102  from the pressed part  100 . First, at the step shown in  FIG.  9 A , a pressed part  100  with a mold portion  102  coupled thereto (i.e., vacuum sealed thereto) is provided. Again, in this embodiment the pressed part  100  includes a generally frustoconical shell having a correspondingly shaped frustoconical mold portion  102  adhered to an internal cavity thereof, but the process could be used with other sized and shaped pressed parts and/or mold portions without departing from the scope of the disclosure. 
     At the step depicted in  FIG.  9 B , the mold holder  114  is removably coupled to the mold portion  102 . For example, in embodiments in which the mold holder  114  includes an opening  146  in the side thereof, the mold holder  114  may be laterally slid onto engagement portion  106  of the mold portion  102  such that the protrusions  148  of the legs  144  are disposed below the lip of the engagement portion  106 . As should be appreciated, in embodiments in which the mold holder  114  includes the washers  126 ,  128  and the tightening bolt  130 , the washers  126 ,  128  and bolt  130  may be pressed into or otherwise integral with the mold holder  114  and thus will be placed on the mold portion  102  at this step as well. At the step depicted in  FIG.  9 C , the extraction rod  116  is placed in the mold holder  114  and, in some embodiments, the mold portion  102  itself. More particularly, in embodiments in which the extraction rod  116  is a threaded rod, it can be threaded into the tightening nut  130  at this step. Moreover, in some embodiments the mold portion  102  may include a receiving hole  108  along the central axis thereof. Thus, at this step the extraction rod  116  can be threaded to a position in which the distal end of the extraction rod  116  extends into the receiving hole  108 , as best seen in  FIGS.  7  and  8   . In such embodiments, the receiving hole  108  may be sized, tapped, and threaded correspondingly such that the extraction rod  116  can be threaded therein and engage with the threads of the receiving hole  108 . 
     At the step depicted in  FIG.  9 D , the pressed part retainer  112  is placed on the extraction rod  116  such that it abuts the pressed part  100  and generally surrounds the mold holder  114 . More particularly, the pressed part retainer  112  is placed on the extraction rod  116  such that the rod extends through the retainer through hole  118  (and, optionally, any washers  122 ,  124 , if equipped) with the bottom rim  138  of the pressed part retainer  112  abutting the pressed part  100 . In embodiments in which the pressed part retainer  112  includes O-rings  140  or similar seal on the bottom rim  138 , the pressed part retainer  112  is placed on the extraction rod  116  with the O-rings  140  abutting the pressed part  100 . As best seen in  FIGS.  7  and  8   , when in this position there is a cavity  150  formed between the mold portion  114  and the pressed part retainer  112 . 
     At the step depicted in  FIG.  9 E , the remaining hardware (such as, e.g., the extraction nut  132 , the oversized washer  134 , and any locking nuts  136 ) are placed on the extraction rod  116  above the pressed part retainer  112 ; i.e., on a side of the pressed part retainer  112  opposite to the cavity  150 . For example, in the depicted embodiment, the oversized washer  134  is placed around the extraction rod  116  and in such a way that it abuts the top surface of the pressed part retainer  112 . The extraction nut  132  is threaded onto the extraction rod  116  until it is snug against the oversized washer  134 . And the locking nuts  136  are threaded onto the proximal end of the extraction rod. 
     The tightening nut  130  and extraction nut  132  are then tightened with respect to one another, thereby reducing the length of the span of the extraction rod  116  extending between the two nuts  130 ,  134 . In this embodiment, a tool (e.g., wrench) can engage one or both of the locking nuts  136 , which will hold the extraction rod  116  in place (i.e., prevent the rod  116  from rotating). Another tool (e.g., wrench) can then engage the extraction nut  132 , and rotate it as depicted by the arrow in  FIG.  9 E  thereby tightening the nut  132  with respect to the tightening nut  130  and thus reducing the length of the span of the extraction rod  116  extending between the two nuts  130 ,  132 . Because the pressed part retainer  112  is immobile (i.e., it is anchored against the pressed part  110  via the O-rings  140  or other seal on the rim  138  engaging the annular portion  103  of the pressed part  100 ), the mold holder  114  will translate toward the pressed part retainer  112  as the extraction nut  132  turns. Put another way, the mold holder  112  will translate along the extraction rod  116  into the cavity  150  provided between the pressed part retainer  112  and the mold holder  114  in response to the reduction in span of the extraction rod  116  extending between the tightening nut  130  and the extraction nut  132 . As the mold holder  114  translates, the mold holder  114  will impart an upward or pulling force on the mold portion  102  via the protrusions  148  of the legs  144  engaging with the lip of the engagement portion  106  and/or via the threads of the extraction rod  116  engaging with the threads of the receiving hold  108 . 
     At the step depicted in  FIG.  9 F , the mold portion  102  is freed from the pressed part  100  as a result of the mold extractor  110  breaking the vacuum seal or other seal formed between the mold portion  102  and the pressed part  100  during the molding process. More particularly, the extraction nut  132  is continually tightened until the mold portion  102  pops free of the pressed part  100 . Such a process beneficially frees the mold portion  102  from the pressed part  100  without the need to dig at the interface of the mold portion  102  and the pressed part  100  with a tool or similar, thereby reducing the likelihood of damaging the pressed part  100  or the mold portion  102 . Following removal, the mold portion  102  can be removed from the mold holder  114  to thereafter be reused in a compression molding process by essentially performing the steps shown in  FIGS.  9 A- 9 E  in reverse. That is, the mold portion  102  can be removed from the mold holder  114  by removing the lock nuts  136 , removing the extraction nut  132  and oversized washer  134 , lifting off the pressed part retainer  112 , unthreading the extraction rod from the mold portion  102  and, optionally, from the tightening nut  130 , and sliding the engagement portion  106  of the mold portion  102  out of the mold holder  114  via the opening  146  provided therein. 
     Although various aspects of the disclosure have been described with reference to the embodiments illustrated in the attached drawings, it is noted that equivalents may be employed without departing from the scope of the invention as recited in the claims.