Title:
Molding-system valve
Kind Code:
A1


Abstract:
Disclosed is: (i) a metal-molding-system valve, (ii) a metal-molding system having a metal-molding-system valve, and (iii) a method of a metal-molding-system valve.



Inventors:
Weir, Sean Ian (Toronto, CA)
Application Number:
11/489981
Publication Date:
01/24/2008
Filing Date:
07/20/2006
Assignee:
Husky Injection Molding Systems Ltd.
Primary Class:
Other Classes:
164/312
International Classes:
B22D13/00; B22D17/08
View Patent Images:



Primary Examiner:
KERNS, KEVIN P
Attorney, Agent or Firm:
HUSKY INJECTION MOLDING SYSTEMS LTD. (BOLTON, ON, CA)
Claims:
What is claimed is:

1. A metal-molding-system valve, comprising: a valve body positionable in a melt-carrying passageway of a metal-molding system, the valve body permitting solidified adherance of a metallic-molding material of melt-carrying passageway to the valve body.

2. A metal-molding-system valve of claim 1, wherein solidified adherance of the metallic-molding material to the valve body permits repeatable operation of the valve body.

3. The metal-molding-system valve of claim 1, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway.

4. The metal-molding-system valve of claim 1, wherein a metallic plug is solidifyable to and meltable from the valve body.

5. The metal-molding-system valve of claim 1, wherein the valve body is slidable within a melt-carrying passageway defined by a metal-molding system.

6. The metal-molding-system valve of claim 1, wherein a metallic plug is formable from a metallic-molding material carried by a melt-carrying passageway defined by a metal-molding system.

7. The metal-molding-system valve of claim 1, wherein a metallic plug is formable from a metallic-molding material, the metallic-molding material including an alloy of magnesium.

8. The metal-molding-system valve of claim 1, wherein a metal-molding component is configured to have a metallic plug formable adjacent thereto.

9. The metal-molding-system valve of claim 1, wherein a metallic plug is adherable and unadherable to and from any one of the valve body, a metal-molding component of the metal-molding system and any combination and permutation thereof.

10. The metal-molding-system valve of claim 1, wherein the valve body is configured to define a cavity, the cavity is configured to have a metallic plug formed therein.

11. The metal-molding-system valve of claim 1, wherein: a metal-molding system has a metal-molding component, the metal-molding component includes a barrel, the barrel defines a melt-carrying passageway; and the valve body is receivable in the melt-carrying passageway.

12. The metal-molding-system valve of claim 1, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway, the cooling mechanism includes cooling circuits adapted to carry a cooling fluid.

13. The metal-molding-system valve of claim 1, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway, the cooling mechanism cooperates with a processing screw and the valve body.

14. The metal-molding-system valve of claim 1, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway, the cooling mechanism cooperates with a processing screw and the valve body, the cooling mechanism includes manifolds configured to communicate a cooling fluid to a cooling circuit defined in the processing screw, the manifolds are mounted to a barrel of a metal-molding system.

15. The metal-molding-system valve of claim 1, wherein the valve body includes a melt-receiving feature.

16. The metal-molding-system valve of claim 1, wherein a metal-molding system includes a barrel, and wherein the valve body includes an outer surface, the valve body is attachable to a processing screw useable in the barrel, the barrel having a barrel inner wall facing the outer surface of the valve body, the outer surface of the valve body configured to be cooled by a mechanism, the cooling mechanism is configured to form a metallic plug between the outer surface of the valve body and the barrel inner wall.

17. The metal-molding-system valve of claim 1, wherein the valve body defines a valve passageway, a metallic plug is formed in the valve passageway.

18. The metal-molding-system valve of claim 1, wherein the valve body defines a valve passageway, a metallic plug is formed in the valve passageway, the valve passageway extends from an accumulation zone to a melt-carrying passageway defined by a processing screw and a barrel.

19. The metal-molding-system valve of claim 1, wherein the valve body cooperates with a valve seal placed between the valve body and a barrel.

20. The metal-molding-system valve of claim 1, wherein the valve body cooperates with a valve heater, the valve heater is locatable adjacent to a valve passageway.

21. The metal-molding-system valve of claim 1, wherein a heating mechanism includes a heat pipe.

22. The metal-molding-system valve of claim 1, wherein a heating mechanism includes a heat pipe embedded in a processing screw.

23. The metal-molding-system valve of claim 1, wherein a metal-molding system includes a barrel, the barrel interacts with a cooling mechanism, the cooling mechanism is configured to cooperate with the barrel, and the cooling mechanism is positionable adjacent to the valve body.

24. The metal-molding-system valve of claim 1, wherein the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of grooves.

25. The metal-molding-system valve of claim 1, wherein the valve body has a longitudinal axis extending therethrough, the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of grooves aligned orthogonal to the longitudinal axis.

26. The metal-molding-system valve of claim 1, wherein the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of any one of rectangular shaped grooves, v-shaped grooves, semispherical-shaped grooves and any combination and permutation thereof.

27. The metal-molding-system valve of claim 1, wherein the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of divots.

28. A metal-molding system, comprising: a metal-molding-system valve, including: a valve body positionable in a melt-carrying passageway of the metal-molding system, the valve body permitting solidified adherance of a metallic-molding material of melt-carrying passageway to the valve body.

29. A metal-molding system of claim 28, wherein solidified adherance of the metallic-molding material to the valve body permits repeatable operation of the valve body.

30. The metal-molding system of claim 28, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway.

31. The metal-molding system of claim 28, wherein a metallic plug is solidifyable to and meltable from the valve body.

32. The metal-molding system of claim 28, wherein the valve body is slidable within a melt-carrying passageway defined by a metal-molding system.

33. The metal-molding system of claim 28, wherein a metallic plug is formable from a metallic-molding material carried by a melt-carrying passageway defined by a metal-molding system.

34. The metal-molding system of claim 28, wherein a metallic plug is formable from a metallic-molding material, the metallic-molding material including an alloy of magnesium.

35. The metal-molding system of claim 28, wherein a metal-molding component is configured to have a metallic plug formable adjacent thereto.

36. The metal-molding system of claim 28, wherein a metallic plug is adherable and unadherable to and from any one of the valve body, a metal-molding component of the metal-molding system and any combination and permutation thereof.

37. The metal-molding system of claim 28, wherein the valve body is configured to define a cavity, the cavity is configured to have a metallic plug formed therein.

38. The metal-molding system of claim 28, wherein: a metal-molding system has a metal-molding component, the metal-molding component includes a barrel, the barrel defines a melt-carrying passageway; and the valve body is receivable in the melt-carrying passageway.

39. The metal-molding system of claim 28, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway, the cooling mechanism includes cooling circuits adapted to carry a cooling fluid.

40. The metal-molding system of claim 28, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway, the cooling mechanism cooperates with a processing screw and the valve body.

41. The metal-molding system of claim 28, wherein responsive to a cooling mechanism cooling the metallic-molding material, a metallic plug is formable between the valve body and the melt-carrying passageway, the cooling mechanism cooperates with a processing screw and the valve body, the cooling mechanism includes manifolds configured to communicate a cooling fluid to a cooling circuit defined in the processing screw, the manifolds are mounted to a barrel of a metal-molding system.

42. The metal-molding system of claim 28, wherein the valve body includes a melt-receiving feature.

43. The metal-molding system of claim 28, wherein a metal-molding system includes a barrel, and wherein the valve body includes an outer surface, the valve body is attachable to a processing screw useable in the barrel, the barrel having a barrel inner wall facing the outer surface of the valve body, the outer surface of the valve body configured to be cooled by a mechanism, the cooling mechanism is configured to form a metallic plug between the outer surface of the valve body and the barrel inner wall.

44. The metal-molding system of claim 28, wherein the valve body defines a valve passageway, a metallic plug is formed in the valve passageway.

45. The metal-molding system of claim 28, wherein the valve body defines a valve passageway, a metallic plug is formed in the valve passageway, the valve passageway extends from an accumulation zone to a melt-carrying passageway defined by a processing screw and a barrel.

46. The metal-molding system of claim 28, wherein the valve body cooperates with a valve seal placed between the valve body and a barrel.

47. The metal-molding system of claim 28, wherein the valve body cooperates with a valve heater, the valve heater is locatable adjacent to a valve passageway.

48. The metal-molding system of claim 28, wherein a heating mechanism includes a heat pipe.

49. The metal-molding system of claim 28, wherein a heating mechanism includes a heat pipe embedded in a processing screw.

50. The metal-molding system of claim 28, wherein a metal-molding system includes a barrel, the barrel interacts with a mechanism, the mechanism is configured to cooperate with the barrel, and the mechanism is positionable adjacent to the valve body.

51. The metal-molding system of claim 28, wherein the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of grooves.

52. The metal-molding system of claim 28, wherein the valve body has a longitudinal axis extending therethrough, the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of grooves aligned orthogonal to the longitudinal axis.

53. The metal-molding system of claim 28, wherein the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of any one of rectangular shaped grooves, v-shaped grooves, semispherical-shaped grooves and any combination and permutation thereof.

54. The metal-molding system of claim 28, wherein the valve body includes a melt-receiving feature, the melt-receiving feature includes a plurality of divots.

55. A method of a metal-molding-system valve, comprising: positioning a valve body in a melt-carrying passageway of a metal-molding system, and permitting solidified adherance of a metallic-molding material of melt-carrying passageway to the valve body.

56. The method of claim 55, further comprising: repeatably operating the valve body inspite of solidified adherance of the metallic-molding material to the valve body.

57. The method of claim 55, further comprising: forming a metallic plug between the valve body and the melt-carrying passageway.

58. The method of claim 55, further comprising: solidifying and melting a metallic plug to and from the valve body.

59. The method of claim 55, further comprising: sliding the valve body within a melt-carrying passageway defined by a metal-molding system.

60. The method of claim 55, further comprising: forming a metallic plug from a metallic-molding material carried by a melt-carrying passageway defined by a metal-molding system.

61. The method of claim 55, further comprising: forming a metallic plug from a metallic-molding material, the metallic-molding material including an alloy of magnesium.

62. The method of claim 55, further comprising: forming a metallic plug formable adjacent to a metal-molding component.

63. The method of claim 55, further comprising: adhereing and unadhereing a metallic plug to and from any one of the valve body, a metal-molding component of the metal-molding system and any combination and permutation thereof.

64. The method of claim 55, further comprising: defining a cavity in the valve body, the cavity is configured to have a metallic plug formed therein.

65. The method of claim 55, further comprising: receiving the valve body in the melt-carrying passageway, a metal-molding system has a metal-molding component, the metal-molding component includes a barrel, the barrel defines a melt-carrying passageway.

66. The method of claim 55, further comprising: forming a metallic plug between the valve body and the melt-carrying passageway responsive to a cooling mechanism cooling the metallic-molding material, the cooling mechanism includes cooling circuits adapted to carry a cooling fluid.

67. The method of claim 55, further comprising: forming a metallic plug between the valve body and the melt-carrying passageway, responsive to a cooling mechanism cooling the metallic-molding material, the cooling mechanism cooperates with a processing screw and the valve body.

68. The method of claim 55, further comprising: forming a metallic plug between the valve body and the melt-carrying passageway responsive to a cooling mechanism cooling the metallic-molding material, the cooling mechanism cooperates with a processing screw and the valve body, the cooling mechanism includes manifolds configured to communicate a cooling fluid to a cooling circuit defined in the processing screw, the manifolds are mounted to a barrel of a metal-molding system.

69. The method of claim 55, further comprising: including a melt-receiving feature in the valve body.

70. The method of claim 55, wherein a metal-molding system includes a barrel, and wherein the valve body includes an outer surface, the valve body is attachable to a processing screw useable in the barrel, the barrel having a barrel inner wall facing the outer surface of the valve body, the outer surface of the valve body configured to be cooled by a mechanism; the cooling mechanism is configured to form a metallic plug between the outer surface of the valve body and the barrel inner wall.

71. The method of claim 55, further comprising: defining a valve passageway in the valve body; and forming a metallic plug in the valve passageway.

72. The method of claim 55, further comprising: defining a valve passageway in the valve body; and forming a metallic plug in the valve passageway, the valve passageway extends from an accumulation zone to a melt-carrying passageway defined by a processing screw and a barrel.

73. The method of claim 55, further comprising: cooperating the valve body with a valve seal placed between the valve body and a barrel.

74. The method of claim 55, further comprising: cooperating the valve body with a valve heater, the valve heater is locatable adjacent to a valve passageway.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

The following is a list of patent applications related to the present application, in which the Applicant's references numbers are: H-903-0-US, HB-903-0-US and HC903-0-US.

TECHNICAL FIELD

The present invention generally relates to molding systems, and more specifically the present invention relates to: (i) a metal-molding-system valve, (ii) a metal-molding system having a metal-molding-system valve, and (iii) a method of a metal-molding-system valve.

BACKGROUND

Examples of known molding systems are (amongst others): (i) the Hylectric™ Molding System, (ii) the Quadloc™ Molding System, (iii) the Hylectric™ Molding System, and (iv) the HyMe™ Molding System, all manufactured by Husky Injection Molding Systems Limited (Location: Bolton, Ontario, Canada; www.husky.ca).

U.S. Pat. No. 4,908,169 (Inventor: Galic et al; Published: Mar. 3, 1990) discloses a plasticisation method using a reciprocating screw having a double-flighted screw to keep a solid bed under compression and to transfer melt films from the screw and a barrel-heated surface.

U.S. Pat. No. 5,040,589 (Inventor: Bradley et al; Published: Aug. 20, 1991) discloses injection molding of metal alloys, such as magnesium alloys, with improved yield, productivity, and mold life.

U.S. Pat. No. 5,680,894 (Inventor: Kilbert; Published: Oct. 28, 1997) discloses an injection-molding apparatus for a metal alloy having dendritic properties. The apparatus includes a sub-ring on a non-return valve assembly, which eliminates piston-ring leakage.

U.S. Pat. No. 5,750,158 (Inventor: Wissmann et al: Published: May 12, 1998) discloses an apparatus for preheating and blending material being fed to an extruder. The apparatus uses co-rotating screws and a close-temperature control to allow the preheating of materials containing a high-mineral filler content without localised heating or compacting.

U.S. Pat. No. 5,843,489 (Inventor: Nakano; Published: Dec. 01, 1998) discloses a screw for an extruder. The screw contains a jacket-shaped, spiral channel around a back side of a screw flight linked to inward and outward channels for a dual tube through a centre hole of a screw core.

U.S. Patent Application Number 2005/0233020A1 (Inventor: Manda et al; Published: Oct. 20, 2005) discloses a non-return valve for use in a molding system. The valve has two complementary spigot portions provided on melt-flow surfaces that are engageable in closely-spaced, overlapping, and parallel arrangement when valve is in a closed configuration.

SUMMARY

According to a first aspect of the present invention, there is provided a metal-molding-system valve, including a valve body positionable in a melt-carrying passageway of a metal-molding system, the valve body permitting solidified adherance of a metallic-molding material of melt-carrying passageway to the valve body.

According to a second aspect of the present invention, there is provided a metal-molding system, having a metal-molding-system valve, including a valve body positionable in a melt-carrying passageway of the metal-molding system, the valve body permitting solidified adherance of a metallic-molding material of melt-carrying passageway to the valve body.

According to a third aspect of the present invention, there is provided a method of a metal-molding-system valve, including positioning a valve body in a melt-carrying passageway of a metal-molding system, and also including permitting solidified adherance of a metallic-molding material of melt-carrying passageway to the valve body.

A technical effect, amongst other technical effects, of the aspects of the present invention is the molding-system valve is less prone to wear.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the exemplary embodiments of the present invention (including alternatives and/or variations thereof) may be obtained with reference to the detailed description of the exemplary embodiments along with the following drawings, in which:

FIGS. 1A and 1B are cross-sectional views of a metal-molding-system valve according to a first exemplary embodiment;

FIG. 2 is a cross-sectional view of a metal-molding-system valve according to a second exemplary embodiment;

FIG. 3 is a cross-sectional view of a metal-molding-system valve according to a third exemplary embodiment;

FIG. 4 is a cross-sectional view of a metal-molding-system valve according to a fourth exemplary embodiment;

FIGS. 5A to 5C are views of metal-molding-system valves according to a fifth exemplary embodiment; and

FIGS. 6A to 6C are views of a metal-molding-system valves according to a sixth exemplary embodiment.

The drawings are not necessarily to scale and are sometimes illustrated by phantom lines, diagrammatic representations and fragmentary views. In certain instances, details that are not necessary for an understanding of the embodiments or that render other details difficult to perceive may have been omitted.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1A is a cross-sectional view of a metal-molding-system valve 100 (hereafter referred to as “the valve 100”) according to the first exemplary embodiment. The valve 100 is used in a metal-molding system 102 (hereafter referred to as the “system 102”) or in a thixo-molding system. A thixo-molding system is used to process a slurry (part liquid, part solid) of a magnesium alloy.

The valve 100 includes a valve body 104 that is positionable in a melt-carrying passageway 108 of the system 102. The valve body 104 permits solidified adherance of a metallic-molding material 110 of (disposed in) melt-carrying passageway 110 to the valve body 104. Preferably, solidified adherance of the metallic-molding material 108 to the valve body 104 permits repeatable operation of the valve body 104. The metallic-molding material 110 is hereafter referred to as the “melt 110”.

Preferably, responsive to a cooling mechanism 116 actuated to cooling the melt 110, a metallic plug 106 is formable between the valve body 104 and the melt-carrying passageway 108. The metallic plug 106 is solidifyable to (formable to, detachably adherable to) and meltable from (deformable from) the valve body 104. The metallic plug 106 (a thixo plug in the case of a thixo-molding system) is formable to the valve body 104. The metallic plug 106 (hereafter referred to as “the plug 106”) is formable from a melt 110 (a metallic molding material). Preferably, the melt 110 includes an alloy composition of magnesium (such as AZ91D). According to a variant, other alloys or types of metals are used (zinc, aluminum, etc).

The valve body 104 defines a cavity 112 in cooperation with a molding-system component 114 (for example: a barrel) of the system 102. For simplifying the description of the first exemplary embodiment, the molding component 114 is hereafter referred to as “the barrel 114”; however, according to other variants, the molding component 114 is a component other than “the barrel”. The cavity 112 is configured to have the plug 106 formed therein at least in part. The valve body 104 includes or defines an outer surface 126. The valve body 104 is attached (preferably threadably attached) to a processing screw 120 having an outer surface 121 and the processing screw 120 is useable in the barrel 114. The barrel 114 defines an outer barrel wall 129 and also defines a barrel inner wall 128 which faces the outer surface 126 of the valve body 104 and faces the processing screw 120.

The outer surface 126 of the valve body 104 is configured to be cooled by a cooling mechanism 116. The cooling mechanism 116 is configured to form a plug 106 between the outer surface 126 of the valve body 104 and the barrel inner wall 128. Details of the cooling mechanism 116 will be described below in more detail.

During the operation of the system 102, the processing screw 120 transports the melt 110 through a melt-carrying passageway 108 which is defined between the barrel inner wall 128 and the outer surface 121 of the processing screw 120. The melt-carrying passageway 108 extends from a hopper (not depicted, but located to the right side of FIG. 1A) to a machine nozzle 144 that extends from the barrel 114. The melt 110 is transported past the valve body 104 and toward the machine nozzle 144 upon rotational actuation of the processing screw 120. The melt 110 is accumulated within an accumulation zone 140 defined between the valve body 104 and the machine nozzle 144. Although the nozzle 144 is depicted (in FIG. 1A) in an open condition, it is understood that a plug (not depicted in FIG. 1A) will be formed within the nozzle 144 by using the cooling mechanism 138; it is understood that once a plug is formed in the nozzle 144, accumulation of the molding material in the accumulation zone 140 may then begin. The melt 110 is deposited into the accumulation zone 140 where the melt 110 is collected (during a recovery phase) and then injected (during an injection phase) into a mold cavity defined by a mold (not depicted) which is operatively connected to the machine nozzle 144.

The processing screw 120 is actuatably rotated via an actuation mechanism (not depicted). Rotation of the processing screw 120 is sufficient to transport the melt 110 into the accumulation zone 140 (this is the recovery phase) and this action builds up an accumulation (or a shot) of melt in the accumulation zone 140. The screw 120 translates away from the machine nozzle 144 during recovery. The actuation assembly then slidably translates the processing screw 120 which injects the shot of melt from the accumulation zone 140 and into the mold cavity (this is the injection phase). Upon slidable translation of the processing screw 120, the valve body 104 becomes slidable and translatable as well since the valve body 104 is connected to the processing screw 120.

The plug 106 is created or formed, within the cavity 112, upon actuation of the cooling mechanism 116 after the shot of melt has been accumulated within the accumulation zone 140. The cooling mechanism 116 cooperates with the processing screw 120 and cooperates with the valve body 104. The cooling mechanism 116 defines a cooling circuit 118A that extends within the processing screw 120 (at least in part). The cooling circuit 118A is, preferably, enwrapped by an insulation layer 119 (at least in part) which avoid the cooling circuit 118A from absorbing heat from the processing screw 120. The valve body 104 defines a cooling circuit 118B that is in fluid communication with the cooling circuit 118A. Preferably, the molding material freezes in the cavity 112 to form the plug 106 and it would be acceptable that some of the molding material was to freeze elsewhere along the surface of the nozzle body 104 which is being generally cooled. The amount of cooling directed to forming the plug 106 should be enough to form the plug and no more to cause adverse cooling of the molding material. The amount of cooling would have to be determined by some experiementation. A layer of frozen molding material may form to and adhere to the front surface of the body 104, but it may be best (preferably) to minimize this condition from occuring.

Preferably, the processing screw 120 cooperates with a manifold 122A and a manifold 122B. Preferably, the manifolds 122A, 122B include rotary-fluid couplings. The manifolds 122A, 122B are adapted to permit the screw 120 to be rotatable (by way of using gaskets, bearings, etc as known to those skilled in the art). The manifold 122A receives, within a coolant holding area, a cooling fluid 125 (under pressure), transfers the cooling fluid 125 into the cooling circuit 118A. The cooling fluid 125 then flows from the cooling circuit 118A, into the cooling circuit 118B of the valve body 104, back into another branch of the cooling circuit 118A and then into the manifold 122B which permits the cooling fluid 125 to exit from the processing screw 120. The cooling fluid 125 removes heat from the valve body 104. In response to the removal of this heat from the valve body 104, the plug 106 is formed adjacent to the valve body 104 and within the cavity 112. The cooling fluid 125 is deposited into the cooling circuits 118A and 118B for a calculated duration and possesses a sufficient cooling effect to form the plug 106.

The valve body 104 includes a melt-receiving feature 124 that faces the cavity 112. The plug 106 is formed and eventually, if the cooling process of the cooling mechanism 116 acts with sufficient duration and strength, adheres to the melt-receiving feature 124. Preferably the plug 106 forms and adheres to both the melt-receiving feature 124 and detachably adheres to the barrel inner wall 128 so as to provide an efficient barrier that prevents backflow of melt from the accumulation zone 140 backwardly toward the hopper and the manifolds 122A and 122B upon translation of the processing screw 120 toward the accumulation zone 140. The plug 106 detachably adheres to the body 104 in that the plug 104 may form and temporarily adhere to the body 104 so as to significantly reduce or prevent leakage of molding material (once the plug 106 is formed and adhered to the body 104); however, the formed and adhered plug 106 is sheared off the from the inner surface of the barrel 114 once the screw 120 is made to translate (but the plug 106 may continue to adhere to the valve body 104 after the plug 106 has been sheared off the barrel 114).

The melt-receiving feature 124 acts to facilitate or enhance bonding with the plug 106 so that as the valve body 104 is translated forwardly toward the machine nozzle 144 the plug 106 does not become detached from the valve body 104. In an alternative embodiment, the valve body 104 does not include the melt-receiving feature 124 since the plug 106 may be adhered to the valve body 104 with sufficient a bonding strength. Generally, the plug 106 is adherable and unadherable (depending on the ability of the cooling mechanism 116) to and from any one of the valve body 104, the barrel 114 and any combination and permutation thereof. The plug 106, although adhered to the barrel 114 and/or to the valve body 104 is shearable from either the valve body 104 and/or the barrel 114 upon actuation of the processing screw 120 which translates the valve body 104 toward the accumulation zone 140. Preferably, the plug 106 is adhered to the melt-receiving feature 124 so that the plug 106 becomes shearable (as close as possible) from the barrel inner wall 128 of the barrel 114 while remaining adhered to the melt-receiving feature 124 of the valve body 106. According to a variant, a small gap (not depicted) is permitted between the formed plug 106 and the inner wall of the barrel, and the small gap is small enough so as to permit creation of a sufficient pressure drop from the front to the back of the valve body 104. After the screw 120 is stroked forwardly, cooling may be shut off and this arrangement permits melting of the plug 106 (if so desired).

Once the injection phase has been completed, the plug 106 is no longer required. The plug 106 is preferably melted by actuation of a heater 132A placed accordingly along the barrel outer surface 129. Before the recovery phase begins, the remaining heaters 132B and 132C may be actuated to melt any solidified melt disposed in the melt-carrying passageway 108, and a thixo plug (not depicted) is formed in the machine nozzle 144. According to a variant, the plug formed in the nozzle 114 may be substituted for a mechanical valve (for example).

FIG. 1B is a detailed cross-sectional view of the valve 100 of FIG. 1A. The valve 100 is shown immediately after the injection phase but before initiation of the recovery phase. For clarity, immediately after injection, the plug 106 may continue to exist (even though the plug 106 has been sheared off the barrel 114). However, the heater 142 may be actuated so as to add heat to the barrel 114 sufficiently enough to melt the plug 106 completely (the melted condition of the plug 106 is depicted in FIG. 1B). During the injection phase, the processing screw 120 is translated forwardly toward the machine nozzle 144, and the melt 110 accumulated in the accumulation zone 140 is then forced through the machine nozzle 144 into the mold cavity of the mold (not depicted). During the recovery phase, the melt 110 is transported by the processing screw 120 along the melt-carrying passageway 108 to deposit into the accumulation zone 140. This accumulation of the melt within the accumulation zone 140 causes the processing screw to translate backwardly toward the manifold 122A (not shown). At this time, the plug 106 may be reheated enough to remelt the plug 106 if so desired.

Prior to the injection phase, a thixo plug (not depicted) is formed within the machine nozzle 144 by using a nozzle cooling mechanism 138. This thixo plug is blown out from the nozzle 144 during the injection phase to allow the melt 110 in the accumulation zone 140 to enter the mold cavity. Upon injecting the melt accumulated in the accumulation zone 140, another shot of the melt 110 must be accumulated. This is accomplished by melting the plug 106 (not shown) which is adhered to the valve body 104 by using the heater 132A. If needed heaters 132B and 132C may be used to melt any potentially solidified melt that may have formed unintentionally (for whatever reason). After a calculated duration, sufficient to melt the plug 106 and reform another thixo plug (not depicted) in the machine nozzle 144, the recovery phase may be repeated. This is then followed by repetition of the injection phase. In a variant (not depicted), the heater 142 is and induction heater that is attached to the barrel 114 to increase effectiveness for melting the plug 106. The induction heater 142 is a fast-acting heating mechanism. According to a variant, a mechanical nozzle is used in place of forming and blowing out a plug from the nozzle 144.

FIG. 2 is a cross-sectional view of a metal-molding-system valve 200 (hereafter referred to as “the valve 200”) according to the second exemplary embodiment. To facilitate an understanding of the second exemplary embodiment, elements of the second exemplary embodiment (that are similar to those of the first exemplary embodiment) are identified by reference numerals that use a two-hundred designation rather than a one-hundred designation (as used in the first exemplary embodiment). For example, the valve body of the second exemplary embodiment is labeled 204 rather than being labeled 104, etc.

Preferably, the valve body 204 includes a valve passageway 209, a valve seal 211, a cooling circuit 218B and a valve heater 213. The valve passageway 209 is defined within the valve body 204, and allows the plug 206 to be formable therein. The valve passageway 209 extends from the accumulation zone 240 to the melt-carrying passageway 208. The passageway 208 is defined by the processing screw 220 and the barrel 214. The valve passageway 208 receives the melt 210, and then it passes the melt 210 to the accumulation zone 240 during a recovery phase.

The valve body 204, which defines a valve body surface 205, accommodates the valve seal 211. The valve seal 211 is located on the valve body surface 205, and the valve seal 211 is adjacent to the barrel 214. The valve seal 211 interacts with the barrel inner wall 228 to substantially prevent a backflow of melt (the metallic molding material) from the accumulation zone 240 along the barrel inner wall 228 and toward the melt-carrying passageway 208 during an injection phase. The valve body 204 defines the cooling circuit 218B. The cooling circuit 218B is connected to the cooling mechanism 216, which is actuated to form the plug 206. The cooling circuit 218B is placed accordingly in the valve body 204 as to not interfere with any mechanisms and/or assemblies defined therein. The valve heater 213 is positionable within the valve body 204 adjacent to the valve passageway 209. The valve heater 213 is electrically connected to a valve-heater connection 215. The valve-heater connection 215 extends from the valve heater 213 into the processing screw 220 and over to an electrical power source (not depicted). The valve heater 213 is placed along the valve passageway 209 to remove the plug 206 prior to commencement of the injection phase. In a variant (not depicted), the heater 213 is omitted and the plug is removed by throttling the cooling to the valve body 204 and allowing the valve body 204 to reheat by conduction from the molding material.

FIG. 3 is a cross-sectional view of a metal-molding-system valve 300 (hereafter referred to as “the valve 300”) according to the third exemplary embodiment. To facilitate an understanding of the third exemplary embodiment, elements of the third exemplary embodiment (that are similar to those of the first exemplary embodiment) are identified by reference numerals that use a three-hundred designation rather than a one-hundred designation (as used in the first exemplary embodiment). For example, the valve body of the third exemplary embodiment is labeled 304 rather than being labeled 104, etc.

The valve body 304 is configured to have a plug 306 formable within the cavity 312. The cooling mechanism 316 includes heat pipes 350. Using heat pipes in screws is known to those skilled in the art (reference is made to Japanese Patent JP 61-188125. Preferably, the valve body 304 and the processing screw 320 are configured to accommodate a set of heat pipes 350 (or a single heat pipe). The heat pipes 350 include a heat conductive material such as aluminum or copper and the heat pipes 350 are filled with a heat-transfer medium (for example: a wick material and/or a coolant medium) that conducts heat from one end of the heat pipes 350 to the other end. Preferably, the coolant medium or the wick material is chosen from a chemical element or composition that absorbs heat effectively (for example: mercury or sodium). Preferably, a sufficient number of heat pipes 350 are used to remove heat from the cavity 312 in order to form (at least in part) the plug 306 therein (preferably after the recovery phase). Preferably, the heat pipes 350 are oriented such that heat is absorbed from the cavity 312 at a receiving end of the heat pipes 350 and then the absorbed heat is transported to a relief end (or an opposite end) of the heat pipes 350. The relief end of the heat pipes 350 is in fluid communication with a manifold 322. Toward the end of the recovery phase, the manifold 322 distributes the coolant fluid 325 (under pressure) over the relief end of the heat pipes 350 to remove heat therefrom. This heat removal from the valve body 304 forms (at least in part) the plug 306. In order to prevent the heat pipes 350 from absorbing heat from the processing screw 320, the heat pipes 350 may be encapsulated within an insulation layer 311. As an option, at the end of injection but before recovery, the heat pipe 350 is permitted to deliver heat to the valve body 304 so as to melt the plug 306. Heat pipes and the operation of heat pipes are known to those skilled in the art, and therefore no further description is provided for heat pipes. According to a variant (not depicted), the heat pipes 350 depicted in FIG. 3 are used along with the valve body 204 of FIG. 2, and this arrangement permits elimination of the heater 213.

FIG. 4 is a cross-sectional view of a metal-molding-system valve 400 (hereafter referred to as “the valve 400”) according to the fourth exemplary embodiment. To facilitate an understanding of the fourth exemplary embodiment, elements of the fourth exemplary embodiment (that are similar to those of the first exemplary embodiment) are identified by reference numerals that use a four-hundred designation rather than a one-hundred designation (as used in the first exemplary embodiment). For example, the valve body of the fourth exemplary embodiment is labeled 404 rather than being labeled 104, etc.

A cooling mechanism 416 is used to form the thixo plug 406. The cooling mechanism 416 cooperates with the barrel 414. The cooling mechanism 416 is positioned adjacent to the valve body 404 along the barrel outer wall 429. The cooling mechanism 416 removes heat from the barrel outer wall 429 adjacent to a region proximate to where the valve body 404 is located. The cooling mechanism 416 delivers a coolant fluid 425 (under pressure) toward the end of the recovery phase to form (at least in part) the plug 406.

FIGS. 5A to 5C are cross-sectional views of metal-molding-system valves 500A, 500B and 500C (hereafter referred to as “the valves 500A, 500B, 500C) according to the fifth exemplary embodiment. To facilitate an understanding of the fifth exemplary embodiment, elements of the fifth exemplary embodiment (that are similar to those of the first exemplary embodiment) are identified by reference numerals that use a five-hundred designation rather than a one-hundred designation (as used in the first exemplary embodiment). For example, the mold body of the fifth exemplary embodiment is labeled 504 rather than being labeled 104. The valves 500A, 500B and 500C each include meli-receiving features 524A, 524B, and 524C respectively, and each has a plurality of various types or shapes of grooves. The valve body 504 has a longitudinal axis 562 that extends from the center therethrough.

FIG. 5A shows the valve 500A that includes the melt-receiving feature 524A that has a plurality of rectangular-shaped grooves 560A, 560B, and 560C that are aligned (preferably) orthogonally to the longitudinal axis 562. The rectangular-shaped grooves 560A, 560B, 560C are arrayed successively at calculated, offset distances therebetween. The arrangement of the rectangular-shaped grooves 560A, 560B, and 560C is not limited to this configuration (for example: they may be irregularly spaced and/or the rectangular-shaped grooves may be inclined non-orthogonally from the longitudinal axis 562).

FIG. 5B shows the valve 500B that includes the melt-receiving feature 524B that has a plurality of v-shaped grooves 564A, 564B, 564C. The v-shaped grooves 564A, 564B, and 564C are arrayed successively at a calculated offset distance between one another. The arrangement of the v-shaped grooves 564A, 564B, and 564C is not limited to this configuration (for example: they may be irregularly spaced apart and/or may be inclined non-orthogonally from the longitudinal axis 562).

FIG. 5C shows the valve 500C that includes the melt-receiving feature 524C that has semispherical-shaped grooves 566A, 566B, 566C. The semispherical-shaped grooves 566A, 566B, and 566C are arrayed successively at a calculated offset distance apart from each other. The arrangement of the semispherical-shaped grooves 566A, 566B, and 566C is not limited to this configuration (for example: they can be irregularly spaced apart from one another and/or may be inclined non-orthogonally from the longitudinal axis 562.

According to a variant (not depicted), the melt-receiving features 524A, 524B, 524C are not used in the valve body 504. According to another variant (not depicted), the melt-receiving features 524A, 524B, 524C are not used in the valve body 504, and the side walls of the body 504 are tapered towards a front end of the body 504 (towards the top side of FIG. 5).

FIGS. 6A to 6C are cross-sectional views of a metal molding-system valve 600 (hereafter referred to as ”the valve 600) according to the sixth embodiment. To facilitate an understanding of the sixth exemplary embodiment, elements of the sixth exemplary embodiment (that are similar to those of the first exemplary embodiment) are identified by reference numerals that use a six-hundred designation rather than a one-hundred designation (as used in the first exemplary embodiment). For example, the mold body of the sixth exemplary embodiment is labeled 604 rather than being labeled 104. The valve 600A, 600B and 600C each include melt-receiving features 624A, 624B, and 624C respectively (each having a plurality of recesses).

FIG. 6A shows the valve 600 that includes the melt-receiving feature 624A that has a plurality of rectangular-shaped recesses 670 that are aligned (in rows) orthogonally to a surface of the valve body 604. The rectangular-shaped recesses 670 are arrayed successively at calculated offset distances from one another. The arrangement of the rectangular-shaped recesses 670 is not limited to this configuration (for example: they may be irregularly spaced and/or inclined non-orthogonally from a longitudinal axis of the valve body 604 and/or placed in a random pattern onto the valve body 604).

FIG. 6B shows the valve 600B that includes the melt-receiving feature 624B includes a plurality of conically-shaped recesses 672. The conically-shaped recess 672 are arrayed successively at calculated offset distances from one another. The arrangement of the conically-shaped recesses 672 is not limited to this configuration (for example: they may be irregularly spaced apart, etc).

FIG. 6C shows the valve 600C that includes the melt-receiving feature 624C that has semispherical-shaped recesses 674. The semispherical-shaped recesses 674 are arrayed successively at a calculated offset distance from each other. The arrangement of the semispherical-shaped recesses 674 is not limited to this configuration (for example: they may be irregularly spaced apart, etc).

According to a variant (not depicted), the melt-receiving features 624A, 624B, 624C are not used in the valve body 604. According to another variant (not depicted), the melt-receiving features 624A, 624B, 624C are not used in the valve body 604, and the side walls of the body 604 are tapered towards a front end of the body 604 (towards the top side of FIG. 6). According to another variant, the melt-receiving feature 624 includes a plurality of divots.

The description of the exemplary embodiments provides examples of the present invention, and these examples do not limit the scope of the present invention. It is understood that the scope of the present invention is limited by the claims. The concepts described above may be adapted for specific conditions and/or functions, and may be further extended to a variety of other applications that are within the scope of the present invention. Having thus described the exemplary embodiments, it will be apparent that modifications and enhancements are possible without departing from the concepts as described. Therefore, what is to be protected by way of letters patent are limited only by the scope of the following claims: