초록 ▼

An apparatus and method for injection molding of thermoplastics has elements and steps comprising mating mold components having multiple mold cavities with flow passages and a plurality of conduits connected to the mold cavities so that thermoplastic can flow into the cavities. A plurality of flow c

An apparatus and method for injection molding of thermoplastics has elements and steps comprising mating mold components having multiple mold cavities with flow passages and a plurality of conduits connected to the mold cavities so that thermoplastic can flow into the cavities. A plurality of flow control members are mounted relative to the mold and to corresponding conduits to be moved to regulate the flow of plastic through corresponding conduits into corresponding cavities to allow for controlling the rate of thermoplastic flow among the cavities. The flow control member can each have a first member movable into its corresponding conduit, and a second adjusting member movable to engage and move the first member. A biasing member can be provided to bias the first member relative to its corresponding conduit. The control members can be inserted to varying degrees within their corresponding conduits to control thermoplastic flow rate among the mold cavities. The flow control member can be controlled by structure external to the mold to allow adjustment of the flow control member. A modification provides for bores extending through outer end surfaces of mold components at an angle of about 45.degree. to about 60.degree. relative to their corresponding mold outer surface. In the modification, a control member can have a threaded section that mates with mold bore threads. The control member can have a non-threaded section distal thereto, a part of which is received within the non-threaded part of the bore for guidance during movement.

대표청구항 ▼

[ What is claimed is:] [1.] A method for controlling the flow rate of thermoplastic into multiple cavities of a mold during injection molding of thermoplastics, comprising the steps of:(a) providing a mold having a first mold component and a second mold component shaped to mate with the first moldin

[ What is claimed is:] [1.] A method for controlling the flow rate of thermoplastic into multiple cavities of a mold during injection molding of thermoplastics, comprising the steps of:(a) providing a mold having a first mold component and a second mold component shaped to mate with the first molding component, with a plurality of mold cavities formed by the first and second mold components when the first and second mold components mate;(b) providing a sprue flow passage for the mold for receiving fluid thermoplastic therethrough;(c) providing the mold with a plurality of conduits, each conduit being in fluid flow connection with the sprue passage and with a corresponding cavity so that fluid thermoplastic can flow from the sprue passage through each conduit into its corresponding cavity;(d) providing means to control the flow of thermoplastic through the plurality of conduits comprising a plurality of flow control members, each said flow control member being movably mounted relative to the mold and relative to its corresponding conduit to move to and fro in directions transverse to its corresponding conduit, each said flow control member being insertable into its corresponding conduit to a desired degree; and(e) moving the control member to be inserted into its corresponding conduit to said desired degree to control the flow rate of thermoplastic through the said corresponding conduit into its corresponding cavity for balancing flow of resin into each of said cavities. [4.] An apparatus for injection molding of thermoplastics, comprising:(a) a mold comprising a first mold component, and a second mold component shaped to mate with the first molding component,. with a plurality of mold cavities formed by the first and second mold components when the first and second mold components mate, so that articles can be molded in the cavities;(b) means for mounting the first and second mold components so that the two mold components can be moved into a mating relationship and can be moved apart from each other away from a mating relationship to allow removal of molded articles from the cavities;(c) the mold having a sprue flow passage for receiving fluid thermoplastic flow therethrough;(d) the mold having a plurality of conduits, each such conduit being in fluid flow connection with the sprue passage and with a corresponding cavity so that fluid thermoplastic can flow from the sprue passage through each conduit into its corresponding cavity;(e) means for controlling the flow rate of thermoplastic through each said conduit comprising a plurality of flow control members, each flow control member being movably mounted relative to the mold, and each flow control member being mounted relative to a corresponding conduit to move to and fro in directions transverse to its corresponding conduit so that the control member can be moved to be inserted at multiple locations within its corresponding conduit to regulate the flow of thermoplastic through the said corresponding conduit into its corresponding cavity so that the flow of thermoplastic through the corresponding conduit into its corresponding cavity can be selectively adjusted, to provide balanced flow of thermoplastic to each of said cavities.