Method and device for manufacturing bent resin pipe
AssigneeThe Yokohama Rubber Co., Ltd.
InventorNobuaki Kuribayashi
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Abstract
A production method and device for a curved resin pipe via resin injection molding that uses an assist material. An inner curve part and/or an outer curve part of a pre-selected curved section of a cavity which is formed in a mold is configured from a temperature-adjustable piece section. After molten resin is injected into the cavity from an injection molding device, the temperature of the piece section is controlled by a control unit such that the inner curve part has a lower temperature than the outer curve part, and an assist material is injected into the cavity from an assist material injection unit and is passed through the cavity so as to form a pipe path. The resin remaining in the cavity is cured to produce a curved resin pipe.
Claims19
A method for manufacturing a bent resin pipe, the method comprising:
- manufacturing a bent resin pipe by injecting molten resin into a cavity that extends while bending and is formed in a pair of molds assembled together, subsequently injecting an assist material into the cavity, and curing the resin injected, wherein
- at least one of a bent inner portion or a bent outer portion of a pre-selected bent portion of the cavity includes a pair of temperature adjustable piece portions respectively incorporated into the pair of molds,
- a surface of one of the piece portions defines only part of the entire length of the cavity in an extension direction of the cavity formed in one of the molds,
- a surface of the other one of the piece portions defines only part of the entire length of the cavity in the extension direction of the cavity formed in the other one of the molds, and
- in injecting the assist material into the cavity, the bent inner portion being caused to have a lower temperature than the bent outer portion by using a control unit for controlling a temperature of the pair of piece portions,
- wherein a heat insulating layer is interposed between the one piece portion and portions of the one mold other than the one piece portion, and
- another heat insulating layer is interposed between the other piece portion and portions of the other mold other than the other piece portion.
A device for manufacturing a bent resin pipe, the device comprising:
- a pair of molds in which a cavity that extends while bending is formed;
- an injection molding machine configured to inject molten resin into the cavity;
- and
- an assist material injection unit configured to inject an assist material into the cavity into which the resin is injected;
- at least one of a bent inner portion or a bent outer portion of a pre-selected bent portion of the cavity is made up of a pair of temperature adjustable piece portions respectively incorporated into the pair of molds,
- a surface of one of the piece portions defines only part of the entire length of the cavity in the extension direction of the cavity formed in one of the molds,
- a surface of the other one of the piece portions defines only part of the entire length of the cavity in the extension direction of the cavity formed in the other one of the molds,
- a control unit configured to control the temperature of the pair of piece portions is included, and
- controlling, in injecting the assist material into the cavity, the temperature of the piece portions from the control unit causes the bent inner portion to have a lower temperature than the bent outer portion,
- wherein a heat insulating layer is interposed between the one piece portion and portions of the one mold other than the one piece portion, and
- another heat insulating layer is interposed between the other piece portion and portions of the other mold other than the other piece portion.
Dependencies are inferred from the claim text.