PART EJECTION SYSTEM FOR INJECTION MOLDING APPARATUS

A method for forming a part in an injection mold includes heating a polymer material to a temperature greater than or equal to a polymer glass transition temperature; injecting the polymer material into the injection molding apparatus of any of the preceding claims while pressing together the stationary half mold surface and the moving half mold surface to form the molding cavity; cooling a surface of the molding cavity with the cooling system; separating the stationary half mold surface and the moving half mold surface; and moving the ejection block relative to the stationary half thereby pushing the part away from the stationary half molding surface and ejecting the part from the injection molding apparatus.

BACKGROUND

An injection molding apparatus can include a stationary half (A side) and a moving half (B side). These sections can be brought together by relative movement of the two sections. When together, molding surfaces from either section can combine to form a part forming mold cavity. A series of passages can convey movable molding material (e.g., material which is molten or at a temperature greater than its glass transition temperature), also referred to as the shot, from the injection machine to the mold cavity. A sprue passage can be in fluid communication with a runner, which can convey the shot through a gate and into the part forming mold cavity. Multiple runners can extend from a sprue to convey the shot to multiple part forming mold cavities.

The runner can be a “hot runner” heated to maintain the temperature of material within the runner such that the material does not solidify (or become more viscous such as to interrupt subsequent shot flow) between shot to shot and during the injection cycle. The runner can be a “cold runner” where material within the runner is cooled during the injection cycles. In the cold runner system the runner can remain attached to the part when the part is ejected from the part forming mold cavity between injection cycles. Advantages and disadvantages of each runner design will be known to those in the art.

BRIEF DESCRIPTION

Disclosed herein is an injection molding apparatus and a method of forming a part in an injection mold.

An injection molding apparatus includes: a stationary half comprising: a sprue opening extending through a thickness of the stationary half forming a sprue passage; a stationary half mold surface; and an ejection block cavity disposed adjacent to the sprue opening; an moving half disposed opposite the stationary half and comprising an moving half mold surface, wherein the stationary half mold surface and the moving half mold surface face one another; a presser in mechanical communication with, and configured to move, the stationary half, the moving half, or both together to form a molding cavity between the stationary half mold surface and the moving half mold surface; an ejection block comprising a mold contact surface forming a portion of the stationary half mold surface, wherein at least a portion of the ejection block is disposed within the ejection block cavity, and wherein the ejection block is configured to movably fit within the ejection block cavity; and an injector for introducing a material to be molded through the sprue passage and into the molding cavity; and a cooling system in thermal communication with at least one of the stationary half mold surface and the moving half mold surface for cooling the material during or after it is introduced into the molding cavity.

A method for forming a part in an injection mold includes: heating a polymer material to a temperature greater than or equal to a polymer glass transition temperature; injecting the polymer material into the injection molding apparatus of any of the preceding claims while pressing together the stationary half mold surface and the moving half mold surface to form the molding cavity; cooling a surface of the molding cavity with the cooling system; separating the stationary half mold surface and the moving half mold surface; and moving the ejection block relative to the stationary half thereby pushing the part away from the stationary half molding surface and ejecting the part from the injection molding apparatus.

DETAILED DESCRIPTION

An advantage of a cold runner injection molding apparatus can include simpler design in comparison to injection molding tools which have hot runners. For example, a cold runner system can have fewer parts and can be free of heated components (e.g., manifolds, nozzles, passages, resistive heaters, or the like) which, when used in a hot runner system, can be disposed internally to a section of the tool. Thus, cold runner mold tools can be less expensive to design and build. However, in cold runner systems the cycle time can be longer, attributed, at least in part, to the runner volume which can increase the shot weight, increase the part volume and cool time accordingly, and can increase the distance that the shot must travel to fill the part cavity. Additionally, the runner of a cold runner system can represent a process waste stream which can require additional handling, storage, processing, and the like, even when the runner is recycled. It can be desirable to design a cold runner injection molding apparatus with a reduced cycle time, but without the cost associated with a hot runner system. Additionally, it can be desirable to reduce the amount of taper from one end of the sprue to the other, e.g., from the runner to the mold surface, to reduce the cross-sectional width of the sprue, to reduce cooling time. If an ejection block is utilized, the angle can be reduced since the ejection block can apply pressure to push the sprue from the stationary half of the mold while also pulling it from the moving half as compared to a mold where, when opening, the sprue is only pulled from the moving half.

Disclosed herein is an injection molding apparatus that can reduce molding cycle time by ejecting a part prior to complete cooling of the runner. For example, with the injection molding apparatus disclosed herein, a part made from the injection molding apparatus can be ejected from the injection mold when overall cooling of the part is at a level of less than 80%, for example, less than 70%, for example, less than 60%. The injection molding apparatus can be a cold runner injection molding apparatus.

FIG. 1is an illustration of a stationary half100and a moving half200of an injection molding tool10and a part300formed therebetween. As shown inFIG. 1, the elements of the injection molding tool10are separated. The stationary half100can include an injection plate120and an injection load plate140. The moving half200can include an ejector plate220and an ejector load plate240. The stationary half100, the moving half200, or both can be in mechanical communication with a presser (e.g., clamp). The presser can move the stationary half100, the moving half200, or both together, such that a stationary half mold surface20(or perimeter thereof) (e.g., a resin surface) and a moving half mold surface30(or perimeter thereof) can directly contact one another forming a molding cavity therebetween. Thus, the presser can act to close the tool during the formation of a part300. The stationary half100can include a locator ring opening150extending through a thickness dimension t of the stationary half100to form a sprue passage156(FIG. 2). The cross-sectional shape of the sprue passage156, the cross-sectional flow area of the sprue passage156, or a combination including at least one of the foregoing can vary along the its thickness dimension.

FIG. 2is an illustration of the injection molding tool10ofFIG. 1in a closed position, where the stationary half100and the moving half200have been brought together to form a molding cavity40therebetween. A portion of the surfaces of the molding cavity40can be formed by the stationary half mold surface20and the moving half mold surface30. The stationary half100can include injection cooling passages110which can be in thermal communication with the stationary half mold surface20. The moving half200can include ejector cooling passages210which can be in thermal communication with the moving half mold surface30. Once the molding material is injected into the molding cavity40it can be cooled by the heat capacity of the injection molding tool10, by a fluid flowing through the injection cooling passages110, by a fluid flowing through the ejector cooling passages210, or a combination comprising at least one of the foregoing. The moving half200can include an ejector pin230. Section170of the injection molding tool10is shown in detail inFIG. 3.

Turning now toFIGS. 3-5,FIG. 3is an illustration of section170of the injection molding tool10ofFIG. 2,FIG. 4is an illustration of an injection molding tool10having an ejection block180in the closed position, andFIG. 5is an illustration of the injection molding tool10ofFIG. 4as the tool is opening.

The injection molding tool10can include an ejection block180. The sprue passage156can extend through the stationary half100. The sprue passage156can extend through the ejection block180. An ejection block cavity190can be formed in the stationary half100(e.g., within the injection plate120). The ejector block cavity190can be disposed adjacent to the sprue passage156, the molding cavity40, or both. A portion of the ejection block180can movably fit within (e.g., tightly fit within the cavity while still being capable of moving in and out, such as a piston and cylinder) of the ejector block cavity190. The ejection block180can include a mold contact surface182. The mold contact surface182can form a portion of the stationary half mold surface20, against which a surface of the part300can directly contact during the molding operation.

The ejection block180can include a pressured surface184. The pressured surface184of the ejection block180can oppose the mold contact surface182. The pressured surface184can be in operable communication with a fluid, a mechanical device (e.g., a spring, pin, and the like), or a combination including at least one of the foregoing which can act on the ejection block180providing a motive force relative to the stationary half100. A portion of the ejection block180can be moved into or out of the ejector block cavity190. For example, when the injection molding tool10is not in the closed position (e.g.,FIG. 5) the ejection block180can be moved away from the stationary half100(e.g., out of the ejector block cavity190) such that only a portion of the ejection block180is disposed within the ejector block cavity190. The ejection block180can press the part300(e.g., a runner308portion, a sprue310portion, or both of part300) away from the stationary half mold surface20by this relative movement. The ejection block180, ejector block cavity190, or both can include a mechanical seal there between which can reduce or eliminate movement of molding material into, or movement of fluid (e.g., pneumatic fluid, hydraulic fluid, or the like) out of the ejector block cavity190. A coating, e.g., a lubricant coating, can be present between the ejection block180and the ejector block cavity190to prevent scratching or shearing during mold movement.

The mold contact surface182can include a sprue contact surface186which can form a portion of a wall of the sprue passage156during the injection cycle and can be in contact with the part300during molding. The mold contact surface182can include a runner contact surface188which can extend from the sprue opening160along at least a portion of the stationary half mold surface20. The runner contact surface188can be adjacent to a portion of a runner308when the part300is formed in the molding cavity40. In an embodiment, the sprue passage156can pass through the ejection block180and the sprue opening160can be formed by the ejection block180.

Once the molding material has cooled in the molding cavity40, the part300can be ejected. The use of the ejection block180can reduce the cooling duration. The use of the ejection block180can reduce the extent that the part is to be cooled prior to ejection in comparison to a molding tool without an ejection block180. For example, a part made from the injection molding tool10can be ejected when overall cooling of the part is at a level of less than 80%, for example, less than 70%, for example, less than 60%. A cooling criteria for part300prior to ejection from the tool when using an ejection block180as described herein can result in a shorter hold duration (e.g., when the tool is closed and the part300is cooling) than when an ejection block180is not used. A cooling criteria can include reaching a threshold temperature at one or more selected measuring points of the part300(e.g., temperature of the part300surface), reaching a threshold temperature of a fluid at one or more selected measuring points in the cooling passages110,210, reaching a threshold temperature of a mold section at one or more selected measuring points (e.g., injection plate120, ejector plate220), the material of the part reaching a threshold viscosity, or a combination including at least one of the foregoing. A threshold temperature can include any temperature. The threshold temperature (e.g., ejectable temperature) can be a temperature below the heat deflection temperature (HDT) of the molding material of the part300, e.g., 1° C. to 45° C. below HDT, or, 1° C. to 30° C. below HDT, or 1° C. to 10° C. below HDT. The threshold temperature can be a temperature below the Vicat temperature of the molding material of the part300, e.g., 1° C. to 45° C. below the Vicat temperature, or, 1° C. to 30° C. below the Vicat temperature, or 1° C. to 10° C. below the Vicat temperature. Using an ejection block180can allow the hold duration for a part to be reduced.

The injection molding tool10can include an ejector pin230. The ejector pin230can include an ejector pin tip end232which can form a surface of the molding cavity40. The ejector pin tip end232, a portion of the ejector plate220adjacent the ejector tip end232or both can include an undercut318. The undercut318can include any shape. As illustrated inFIG. 6, the undercut318can include a converging shape. As illustrated inFIG. 7, the undercut318can include a zig-zag interface. As illustrated inFIG. 8, the undercut318can include a notched interface. As illustrated inFIG. 9, the undercut318can include a diverging shape. The undercut318can be shaped to increase the contact area between the part300and the ejector pin230, between the part300the ejector plate220, or between the part300and the ejector pin and between the part300and the ejector pin230in comparison to the planar interface. For example,FIG. 6illustrates an undercut318having a converging shape formed in the ejector plate220which can converge from the ejector tip end232to the runner308. A shape of the ejector pin230can be oriented such that when the tool is opened the part300can fall away from the ejector pin230(e.g., a vertical notch that allows the part300to move in the direction of gravity when the pin is moved away from the ejector plate220).

The ejector pin230can be located adjacent to any portion of the part300. The ejector pin230can be located adjacent the runner308. The ejector pin230can be located opposite the sprue passage156. The ejector pin230can hold a part300against the moving half mold surface30while the tool is opened. When the sections are separated, such as when the tool is transitioning from the closed position to the open position, the part300is held against the moving half200(e.g., against the moving half mold surface30). The ejector pin230and the ejection block180can cooperate to separate part300from the stationary half100when the tool is opened. The ejector pin230can be moved relative to the moving half200to separate the part300from the moving half200(e.g., from the moving half mold surface30after the tool is opened).

FIG. 10is a top view of an illustration of the part300molded in the injection molding tool ofFIGS. 1-3. The part300includes two sub-parts302formed on opposite sides of a shot distributing sprue310and runner308. The shot distribution system includes a sprue310and a runner308interconnecting the sprue310and the sub parts302. The longest dimension of the sprue310and the longest dimension of the runner308can extend orthogonal to one another. For example, the longest dimension of the sprue310can extend in the t dimension (seeFIG. 15) while the longest dimension of the runner308can extend in the d or h dimensions (seeFIG. 14) in the accompanying figures. As illustrated inFIG. 15, the sprue310has the longest dimension in the t dimension, whileFIG. 14illustrates that the runner can have the longest dimension in the d or h dimensions. The runner308can have a larger flow area than the part300. For example, the largest flow area can be at the junction of runner308and sprue310.

FIG. 11is a cross-sectional view of the part300along the A-A cross section ofFIG. 10. The sprue310extends orthogonal to the subparts302.

FIG. 12is a detailed view of the section330of the part300ofFIG. 11. The section330includes the sprue310, runner308, and a portion of the subparts302. The sprue310can include an injection end311and a part end312. The sprue310can have any shape. The sprue can have a conical shape to correspond with a nozzle of the injection molding machine. The sprue310can have a sprue length319. The sprue310can have an injection end width313. The sprue310can have a sprue end width314. The injection end width313and the sprue end width314can be measured in a plane orthogonal to the sprue length319, e.g., measured along the h dimension. The injection end width313can be less than the sprue end width314. The sprue310can be widest at a cross-section between the injection end311and the part end312, such as at a point which was formed within the sprue opening160during the molding operation. A surface of the sprue310can extend from the injection end311at an angle316which is less than to 90° measured relative to a cross-sectional plane315orthogonal to the length319of the sprue, for example the angle can be from 75° to 90°, or, 85° to 90°. The flow area of the runner308(e.g., measured in the t-d plane) can be less than the flow area of the sprue310(e.g., measured in the h-d plane). The sprue310can include an undercut318. The undercut318can include any shape, such as those illustrated inFIGS. 6 to 9.

A wall of the sprue passage156(forming the wall of the sprue310) can extend at a draft angle317of less than 10° relative to a theoretical cylinder wall350which extends from the sprue opening160to the locator ring opening150of a stationary half100, for example, the draft angle317can be 1° to 10°, or 1° to 5°.FIGS. 16 and 17illustrate the sprue310where the draft angle317inFIG. 16is reduced as compared toFIG. 12and wherein the draft angle317inFIG. 17is reduced as compared toFIG. 12andFIG. 16. As also illustrated inFIG. 16andFIG. 17, sprue end width314can be reduced with the injection molding tool10as described herein. As demonstrated inFIG. 17, a smaller sprue end with314(e.g., sprue diameter322) with a corresponding smaller draft angle317can produce the same injection end width313as compared toFIG. 16(see larger sprue diameter320inFIG. 16). A smaller draft angle317can lead to a reduction in sprue end width314, which can mean less material needed to fill the mold, shorter cooling time, and therefore, shorter overall cycle time.

FIG. 13is an illustration of the part300in a three dimensional space. The part300can include ejection block runner contact surface380, where the ejection block180was in contact with the part300during molding. The part300can include an ejection block sprue contact surface381where the ejection block180was in contact with the part300during molding. The ejection block runner contact surface380can extend across a portion of a surface of the runner308. The ejection block sprue contact surface381can extend over a portion of a surface of a wall of the sprue310. The walls of the sprue passage156can diverge as it extends to the sprue opening160and the sprue passage156can extend through the ejection block180such that an ejection block180can push against a wall of the sprue310(e.g., along the t dimension in the accompanying figures) when the part300is to be ejected from the tool. The ejection block runner contact surface380and the ejection block sprue contact surface381can be removed from the sub parts302along with the sprue310and runner308during finishing operations performed on part300. Such operations can include any material removal process, e.g., cutting, machining, grinding, filing, sanding, and the like. The runner308can be broken from the part300when the part is ejected from the tool.

The molding material can be any material that can be flowed into the molding cavity40. For example, the molding material can include a polymer, including, but not limited to amorphous, semi-crystalline, crystalline, elastomers, etc. For example, a polymer can include thermoplastic materials such as polybutylene terephthalate (PBT); polypropylene (PP); polyethylene (PE) (e.g., high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE); polyamides (PA) (e.g., nylon); polyphenylene sulfide (PPS); polysulfone (e.g., polyethersulfone (PES)); polyether ketone (PEK) (e.g., polyether ether ketone (PEEK); polyester (e.g., polyethylene terephthalate (PET)); polyetherimides (PEI); acrylonitrile-butadiene-styrene (ABS); polycarbonate (PC); polycarbonate/PBT blends; polycarbonate/ABS blends; copolycarbonate-polyesters; blends of polycarbonate/polyethylene terephthalate (PET)/PBT; as well as combinations comprising at least one of the foregoing. A polymer material can include additives, e.g., an impact modifier, ultraviolet light absorber, mold release agent, anti-dripping agent, flame retardant, anti-graffiti agent, pigment, or a combination including at least one of the foregoing. The molding materials can include reinforcing materials, such as glass, carbon, basalt, aramid, or combination comprising at least one of the foregoing. Reinforcing materials can include cut, chopped, strand fibers, or a combination comprising at least one of the foregoing.

A molding process using the molding tool disclosed herein can include moving a stationary half100and the moving half200of an injection molding tool10together, forming a molding cavity40between the stationary half100and the moving half200, forming a molding cavity40between the stationary half mold surface20and the moving half mold surface30, or a combination including at least one of the foregoing.

The molding process can include heating a molding cavity40, heating a sprue passage156, heating a runner passage, heating a part forming mold cavity, heating a moldable material, frictionally heating a moldable material with a ram or screw, or a combination including at least one of the foregoing.

The molding process can include injecting a moldable material into the molding cavity40at an injection pressure of 1 MegaPascal (MPa) to 400 MPa, pressing the stationary half100and the moving half200together and pressing the moldable material into the mold cavity. The molding process can include cooling a portion of a part300until a cooling criteria is satisfied, cooling a part300until a surface temperature of the part300decreases below an ejectable temperature, cooling a part300while a molding tool is closed, holding a molding tool in a closed position for a specified time duration, holding a molding tool in a closed position until a cooling criteria has been satisfied, or a combination including at least one of the foregoing.

The molding process can include separating the stationary half100and the moving half200, separating the stationary half mold surface20and the moving half mold surface30to open the molding cavity40, moving the stationary half mold surface20and the moving half mold surface30away from one another, ejecting a part300from a molding tool with an ejection block180at an ejection pressure of 1 Pascal (Pa) to 100 Pascals, moving an ejection block180within an ejection block cavity190where an mold contact surface182extends away from a stationary half mold surface20, pressing a pressured surface184of an ejection block180with a fluid, pressing a pressured surface184of an ejection block180with a mechanical device, pushing a part300along an ejection block runner contact surface380with the runner contact surface188of an ejection block180, pushing a part300along an ejection block sprue contact surface381with the sprue contact surface186of an ejection block180, pushing a part300with more than one ejection block180, or a combination including at least one of the foregoing.

The molding process can include holding a part300in direct contact with the moving half mold surface30by interlocking the part300onto the ejector plate220with an undercut318, pushing a part300away from a moving half mold surface30with a ejector pin230, pushing a part300with more than one ejector pin230, or a combination including at least one of the foregoing. The mold process can include can include holding a part300in direct contact with the moving half mold surface30by interlocking the part300onto the ejector plate220without an undercut, pushing a part300away from a moving half mold surface30with a ejector pin230, pushing a part300with more than one ejector pin230, or a combination including at least one of the foregoing

EXAMPLE

The injection tool ofFIG. 1was used with a shot including polycarbonate, acrylonitrile-butadiene-styrene (ABS), and glass filler to mold the part300with and without the use of the ejection block180to push the part from the stationary half100of the tool. The shot composition included 15 weight percent glass filler. The time to part ejection for the part300when the ejection block180was not used was 22 seconds. The time to part ejection for the part300when the ejection block180was used was 18 seconds. Thus, the time to part ejection was reduced by 18.2% with the use of the ejection block180. The other cycle time for the molding process was 13.34 seconds (e.g., to close the tool, inject the shot, and open the tool), which was unchanged. In this example the total cycle time was reduced from 35.34 seconds to 31.34 seconds upon the use of the ejection block180resulting in an 11.3% cycle time reduction. Ejection can be accomplished with the use of spring tension poles (e.g., coil springs).

The injection molding apparatus and method for forming a part in an injection mold include at least the following embodiments:

Embodiment 1: An injection molding apparatus comprising: a stationary half comprising: a sprue opening extending through a thickness of the stationary half forming a sprue passage; a stationary half mold surface; and an ejection block cavity disposed adjacent to the sprue opening; an moving half disposed opposite the stationary half and comprising an moving half mold surface, wherein the stationary half mold surface and the moving half mold surface face one another; a presser in mechanical communication with, and configured to move, the stationary half, the moving half, or both together to form a molding cavity between the stationary half mold surface and the moving half mold surface; an ejection block comprising a mold contact surface forming a portion of the stationary half mold surface, wherein at least a portion of the ejection block is disposed within the ejection block cavity, and wherein the ejection block is configured to movably fit within the ejection block cavity; and an injector for introducing a material to be molded through the sprue passage and into the molding cavity; and a cooling system in thermal communication with at least one of the stationary half mold surface and the moving half mold surface for cooling the material during or after it is introduced into the molding cavity.

Embodiment 2: The injection molding apparatus of Claim1, wherein the stationary half comprises a stationary half mold cavity wherein at least a portion of the stationary half mold surface is disposed within the stationary half mold cavity.

Embodiment 3: The injection molding apparatus of Claim1or Claim2, wherein the moving half comprises a moving half mold cavity and at least a portion of the moving half mold surface is disposed within the moving half mold cavity.

Embodiment 4: The injection molding apparatus of any of the preceding claims, wherein the sprue passage extends through the ejection block.

Embodiment 5: The injection molding apparatus of any of the preceding claims, wherein the molding cavity comprises a part forming space and a runner space interconnecting the sprue passage and the part forming space.

Embodiment 6: The injection molding apparatus of any of the preceding claims, wherein the mold contact surface of the ejection block further comprises a sprue contact surface extending from the sprue opening along at least a portion of a wall of the sprue passage, and a runner contact surface extending from the sprue opening along at least a portion of the stationary half mold surface.

Embodiment 7: The injection molding apparatus of any of the preceding claims, wherein a wall of the sprue passage extends from the sprue opening at an angle of less than or equal to 90° measured relative to a cross-sectional plane of the sprue opening.

Embodiment 8: The injection molding apparatus of any of the preceding claims, wherein the sprue passage has a conical shape that converges as it extends from the sprue opening to an injector opening, and wherein a wall of the sprue passage extends at a draft angle of less than or equal to 5° measured relative to the wall of a theoretical cylindrical sprue passage extending from the sprue opening.

Embodiment 9: The injection molding apparatus of any of the preceding claims, wherein the ejection block further comprises a pressured surface and the ejection block is moved relative to the stationary half by pressuring the pressured surface with a fluid or a mechanical device, or a combination comprising at least one of the foregoing.

Embodiment 10: The injection molding apparatus of any of the preceding claims, wherein the ejection block is configured to be moved relative to the stationary half by an electromagnetic force, a pneumatic force, a hydraulic force, a mechanical force, or a combination comprising at least one of the foregoing.

Embodiment 11: The injection molding apparatus of any of the preceding claims, wherein the ejector cavity, or the ejection block, or the ejector cavity and the ejection block further comprise a seal therebetween for retaining a fluid within at least a portion of the ejection block cavity.

Embodiment 12: The injection molding apparatus of any of the preceding claims, wherein the material can be pushed from the molding cavity by the ejection block following a molding operation without separating material formed in the sprue passage from material formed within the molding cavity.

Embodiment 13: The injection molding apparatus of any of the preceding claims, wherein the moving half further comprises an ejector pin cavity and an ejector pin configured to movably fit within the ejector pin cavity, wherein at least a portion of the moving half molding surface is disposed within the ejector pin cavity.

Embodiment 14: The injection molding apparatus of Claim13, wherein the ejector pin or the ejector pin cavity, or the ejector pin and the ejector pin cavity comprise an undercut or cooperate to form an undercut configured to hold the material adjacent to the moving half when the injector section and the moving half are separated.

Embodiment 15: The injection molding apparatus of any of the preceding claims, wherein the ejector pin is configured to push the material away from the moving half.

Embodiment 16: The injection molding apparatus of any of the preceding claims, wherein the injection molding apparatus is a cold runner injection molding apparatus or a semi-cold runner injection molding apparatus.

Embodiment 17: A method for forming a part in an injection mold comprising: heating a polymer material to a temperature greater than or equal to a polymer glass transition temperature; injecting the polymer material into the injection molding apparatus of any of the preceding claims while pressing together the stationary half mold surface and the moving half mold surface to form the molding cavity; cooling a surface of the molding cavity with the cooling system; separating the stationary half mold surface and the moving half mold surface; and moving the ejection block relative to the stationary half thereby pushing the part away from the stationary half molding surface and ejecting the part from the injection molding apparatus.

Embodiment 18: The method of Claim17, wherein the moving further comprises pulling the part with an ejector pin extending from the moving half.

Embodiment 19: The method of Claim17or Claim18, wherein the part is pulled from the injection mold at an overall cooling level of less than 80%.

Embodiment 20: The method of any of Claims17-19, wherein the polymeric material is selected from polypropylene; polyethylene; polyamide; polysulfone; polybutylene terephthalate; polyetherimides; acrylonitrile-butadiene-styrene; polycarbonate; polycarbonate/polybutylene terephthalate blends; polycarbonate/acrylonitrile-butadiene-styrene blends; copolycarbonate-polyesters; blends of polycarbonate/polyethylene terephthalate/polybutylene terephthalate; or a combination comprising at least one of the foregoing.

In general, the invention may alternately comprise, consist of, or consist essentially of, any appropriate components herein disclosed. The invention may additionally, or alternatively, be formulated so as to be devoid, or substantially free, of any components, materials, ingredients, adjuvants or species used in the prior art compositions or that are otherwise not necessary to the achievement of the function and/or objectives of the present invention.