Patent Application
20080012176
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:
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.
According to a variant, the thixo-molding station 110 processes and/or maintains a metal molding material in a thixotropic (slurry) state. According to another variant, the thixo-molding station 110 operates at the near-liquidus range of a metal molding material. The metal olding material may be a magnesium alloy, a zinc alloy, or a metal-matrix composite, which is a combination of a metal alloy and a reinforcement (such as a ceramic powder), etc.
Preferably, the system 100 includes a mold-moving assembly 102. The mold-moving assembly 102 cooperates with: (i) a molding station 110 to mold articles, and (ii) an overmolding station 112 to overmold (at least in part) the molded articles that were molded in the molding station 110. The mold-moving assembly 102 moves the molded articles from the molding station 110 over to the overmolding station 112. A technical effect is, amongst other things, increased cycle time by increasing system integration, and/or a reduction in an accumulation of molded articles between the molding station 110 over to the overmolding station 112.
Preferably, operation of the molding station 110 and operation of the overmolding station 112 overlap one another (at least in part) so that a reduction in cycle time is achieved (another technical effect). Even more preferably, operation of the molding station 110 and operation of the overmolding station 112 overlap each other simultaneously or near simultaneously (that is, overlap of operations occur concurrently) for the best possible reduction in cycle time (another technical effect).
The molding station 110 molds articles made from a molding material, such as: (i) a plastic-based molding material, or (ii) a metal-based molding material. The overmolding station 112 overmolds the molded article with another molding material, such as: (i) a plastic-based molding material, or (ii) a metal-based molding material. The molding material may include a reinforcement material, such as: (i) fibers, (ii) a ceramic powder, or (iii) a colorant, etc.
Preferably, a set of mold halves (106, 108) is attached to the mold-moving assembly 102. The set of mold halves (106, 108) includes: (i) a mold half 106, and (ii) a mold half 108. The mold-moving assembly 102 translates the mold halves 106, 108 along a horizontally-aligned axis (as depicted). According to a variant (not depicted), the mold-moving assembly 102 translates mold halves 106, 108 along a vertically-aligned axis.
Actuators 111 (along with another pair of actuators that are hidden in this view) are used to actuatably translate (slide or stroke) the mold-moving assembly 102 along a base 104 toward and away from the molding station 110 so that the mold halves 106, 114 may be opened or closed relative to each other. A mold half 114 is part of the molding station 110. The mold-moving assembly 102 includes rotation actuators (not depicted) used to move (preferably, rotate) the set of mold halves (106, 108) between the stations 110, 112 so that (i) the mold half 106 is depicted positioned in the molding station 110, and (ii) the mold half 108 is depicted positioned in the overmolding station 112.
The molding station 110 uses a group of mold halves (106; 108; 114) to a mold articles by alternately using the combination of: (i) mold halves (106, 114), or (ii) mold halves (108, 114). A molded article 130 is currently positioned in the station 112, and it was moved over from the station 110 to the station 112. The group of mold halves (106; 108; 114) shares at least one mold half that is common with the set of mold halves (106; 108). The mold half 114 is attached to a stationary platen 116. The actuators 111 are actuated to translate the mold-moving assembly 102 toward and away from the stationary platen 116 so that the mold halves 106, 114 may be: (i) closed against each other, or (ii) separated from each other. Once the mold halves 106, 114 are closed together, a clamping mechanism 123 is actuated to apply a clamping force (via tie bars 117) that clamps up the mold halves 106, 114. Once closed together and clamped up, the mold halves 106, 114 define a mold cavity, into which a primary-injection unit 118 will inject a primary molding material into the mold cavity of the mold halves 106, 114. Once the molded article is solidified in the mold cavity, the clamping mechanism 123 will be actuated to apply a mold-break force that acts to break apart the mold halves 106, 114. Once the mold halves 106, 114 are broken apart, the actuators 111 will be actuated to move the mold-moving assembly 102 away from the mold half 114 so as to so separate the mold halves 106, 114. The mold half 106 retains the molded article so that the mold-moving assembly 102 may then be actuated to rotate the mold halves 106, 108, and the molded article may be rotatably moved over to the overmolding station 112.
The overmolding station 112 uses a collection of mold halves (106; 108; 120) to overmold a secondary molding material into (on to, relative to, etc) the molded article 130 by alternately using the combination of: (i) the mold halves (106, 120) or, (ii) the mold halves (108, 120). The molded article 130 is currently positioned in a mold cavity defined by the mold halves 108, 120 that are closed together and clamped up relative to each other. The collection of mold halves (106; 108; 120) shares at least one “common” mold half with the set of mold halves (106, 108). The mold 120 is attached to a movable platen 122. An actuator 109 (along with another actuator that is hidden in this view) is used to translate (stroke or slide) the movable platen 122 along the base 104 toward and away from the mold-moving assembly 102 so that the mold halves 108, 120 may be opened and closed relative to each other. Once the actuator 109 has closed the mold halves 108, 120 together, the clamping mechanism 123 applies a clamp force to the mold halves 108, 120, and then the secondary molding material will be injected into the mold cavity defined by the mold halves 108, 120 so that the molded article 130 will become overmolded (at least in part).
The tie bars 117 are attached to the stationary platen 116 and extend from the stationary platen 116 through the movable platen 122 and over to a tie-bar support structure 119. Structure 119 is optional. Preferably, the structure 119 is used to prevent the tie bars 117 from sagging (that is, if: (i) the tie bars 117 are not stiff enough or, (ii) the tie bars 117 are too long). Preferably, the clamping mechanism 123 is: (i) contained in the movable platen 122, (ii) actuatable to apply the clamping force or to apply the mold-break force via the tie bars 117 so that these forces may then be transmitted and applied to the mold halves that have been closed. A known structure of the clamping mechanism 123 is a pineapple-type mechanism as known in the molding-system art.
The actuator 109 was actuated to stroke the platen 122 toward the mold-moving assembly 102 so that the mold halves 108, 120 became closed relative to each other; then, the clamping mechanism 123 was actuated to apply the clamping force to the mold halves 108, 120. A secondary-injection unit 124 will be used to inject the secondary molding material into the mold cavity defined by the mold halves 108, 120. The secondary molding material will overmold (at least in part) the molded article 130 positioned in the mold cavity to manufacture an overmolded article 132 (depicted in
Preferably the primary-injection unit 118 is a metal-injection unit that injects a metallic alloy (such as: an alloy of magnesium, etc) into the mold cavity to mold a metallic article; and the secondary-injection unit 124 is a plastic-injection unit that injects a plastic-based resin that overmolds the molded metallic article. If the molded article includes a metallic component, a conditioning station 128 includes a cooling bath that is used to spray a coolant (such as water) at the molded metallic article (so as to cool down the metallic article before it becomes overmolded. According to a variant, the conditioning station 128 includes other types of mechanisms for conditioning the molded article, such as cutting, removing, trimming, painting, coating and/or heating of portions of the molded article.
The one or more instructions 206 include instructions for directing instructions for directing a mold-moving assembly 102 to cooperate with a molding station 110 to mold an article, cooperate with an overmolding station 112 to overmold, at least in part, another article that was molded by the molding station 110 in cooperation with the mold-moving assembly 102, and move molded articles between the molding station 110 and the overmolding station, and also include instructions for directing operation of the molding station 110 and operation of the overmolding station 112 to overlap one another at least in part to reduce cycle time.
Preferably, the instructions 206 include the following instructions (in no particular order):
(i) instructions for directing the mold-moving assembly 102 to move a set of mold halves 106, 108 between the molding station 110 and the overmolding station 112, and instructions for directing the set of mold halves 106, 108 to cooperate with the molding station 110 to form the molded article 130 at least in part;
(ii) instructions for directing the mold-moving assembly 102 to move a set of mold halves 106, 108 between the molding station 110 and the overmolding station 112, and instructions for directing the molding station 110 to include a group of mold halves 106, 108, 114 configured to cooperate with the set of mold halves 106, 108 to form the molded article 130 at least in part;
(iii) instructions for directing the mold-moving assembly 102 to move a set of mold halves 106, 108 between the molding station 110 and the overmolding station 112, and instructions for directing the set of mold halves 106, 108 to cooperate with the overmolding station 112 to encapsulate a molding material relative to the molded article 130 at least in part;
(iv) instructions for directing the mold-moving assembly 102 to move a set of mold halves 106, 108 between the molding station 110 and the overmolding station 112, and instructions for directing the overmolding station 112 includes a collection of mold halves 106, 108, 120 configured to cooperate with the set of mold halves 106, 108 to overmold a molding material relative to the molded article 130 at least in part;
(v) instructions for directing the mold-moving assembly 102 to rotate a set of mold halves 106, 108 between the molding station 110 and the overmolding station 112;
(vi) instructions for directing the mold-moving assembly 102 to linearly translate a set of mold halves 106, 108 between the molding station 110 and the overmolding station 112;
(vii) instructions for directing the mold-moving assembly 102 to move a set of mold halves 106, 108 between the molding station 110 and the overmolding station 112, and instructions for directing a retaining structure of the set of mold halves 106, 108 to releasably retain the molded article 130; and
(viii) instructions for directing the molding station 110 to mold the molded article 130, and instructions for directing the overmolding station 112 to overmold the molded article 130).
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:
