JP2007283730A - Molding mold for injection molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding mold for injection molding by which a sprue portion and a runner portion are effectively cooled at a low cost and molding circle can be shortened. <P>SOLUTION: In a mold constituted of a plurality of mold members, forming a sprue and a runner, and performing injection molding, the mold members has hole portions or recessed portions 14 to 16 for forming the sprue or the runner, and a cooling air passage way portions 17 to 23 are arranged in the vicinity of the hole portions or the recessed portions. In the mold members, a groove 27 which is a passage of the cooling air is arranged in the vicinity a sprue bush 13 having the hole for forming the sprue which is the hole portion 14 for forming the sprue in the surface thereof. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a mold injection mold that molds a molded product, and more particularly to a mold injection mold that can shorten a molding cycle easily and at low cost.

  An injection mold is used when a molded product is manufactured by injecting a high-temperature molten resin and performing a molding operation. Many of the molds require a runner for flowing the resin from the sprue for injecting the molten resin to the molding part in terms of the mold structure.

  Molded products are becoming thinner and less solidified every year, but the mold sprue and runner are thick and difficult to cool down during molding, so it is difficult to solidify and the molding time becomes longer. It will go down and production efficiency will deteriorate. In general, in order to cool and solidify a high-temperature molten resin and shorten the molding cycle, a circuit for flowing water as a cooling medium is provided inside the mold. A water cooling circuit is also set for the mold sprue bushings and runner groove processed members, and cooling is performed. However, the sprue bushing member with the water cooling circuit must have a reliable sealing structure to prevent water leakage. Therefore, the water cooling circuit of the runner part often has a complicated runner configuration, and thus an effective cooling circuit configuration may not be possible. In addition, the cost is high because equipment such as a device for adjusting the mold temperature is required. This water-cooled circuit structure may lead to accidents such as mold corrosion due to water leakage.

In addition, a cooling circuit configuration by water cooling requires a lot of costs, and it is difficult to set up an effective circuit. Further, since the cooling medium is water, it has been proposed to use a cooling circuit by air cooling in order to solve problems such as corrosion of the mold due to water leakage (see Patent Documents 1 and 2).
JP-A-11-333898 JP 2003-71278 A

  In the conventional cooling circuit structure by air cooling, the structure of the member which comprises a metal mold | die becomes complicated, and there existed a subject that cost became high. An object of the present invention is to provide a mold injection mold capable of efficiently cooling a sprue portion and / or a runner portion at low cost and shortening a molding cycle.

  In order to achieve the above object, the present invention provides an air groove for cooling at a position 0.5 to 2 mm away from the sprue forming portion or runner forming portion of the mold, and cooling air is supplied to the groove. This is a mold that allows the sprue and runner, which are high-temperature molten resin injected and filled, to be cooled and solidified in a short time.

  That is, the present invention comprises a plurality of mold members, and in a mold for forming a sprue and a runner and performing mold injection molding, at least one of the mold members has a hole or a recess for forming a sprue or a runner. And a mold injection mold having a cooling air passage in the vicinity of the hole or the recess.

  According to the present invention, at least one of the mold members is a sprue bush having a hole portion that forms a sprue, and a cooling air is provided on a surface of the sprue bush and in the vicinity of the hole portion that forms the sprue. The mold injection mold which provided the groove | channel used as this passage.

  In the present invention, at least one of the mold members is a groove serving as a cooling air passage in the vicinity of a hole or a recess forming a sprue or a runner and on a joint surface with another mold member. Is a mold injection mold provided with

  Furthermore, the present invention is a mold injection mold in which at least one of the mold members is provided with a groove serving as a passage for cooling air along the periphery of the recess forming the runner.

  Moreover, this invention is a mold injection mold which has a heating means in the vicinity of the hole or recessed part which forms the said sprue or a runner.

  According to the present invention, in the mold for injection molding, the effect of cooling the sprue or runner is enhanced, and the sprue and runner, which are high-temperature molten resins, are cooled and solidified in a short time, thereby shortening the molding cycle and improving the mass productivity. Can be obtained. In addition, since air is used as the cooling medium instead of water, it is not necessary to have a reliable sealing structure. Therefore, the cooling circuit can be configured at low cost, and the temperature controller is not required. Leakage is eliminated and problems such as mold corrosion that have been caused by using cooling water are also improved. In addition, this air cooling can also provide an effective cooling effect for a mold whose temperature is adjusted by a heating means such as a cartridge heater.

The best mode for carrying out the present invention will be described.
Embodiments of the mold injection mold according to the present invention will be described with reference to the drawings.

  Examples will be described. The mold injection mold of the present embodiment is composed of a plurality of mold members, and a part of the mold member has a hole or a recess for forming a sprue or a runner, and a cooling air passage in the vicinity of the hole or the recess. Is provided. The cooling air passage portion is preferably provided on a joint surface with another mold member. FIG. 1 shows a mold injection mold structure employing the cooling method of the present invention. Reference numeral 1 denotes a fixed-side mounting plate, which is a member for mounting the fixed-side mold to the injection molding machine. Reference numeral 2 denotes a fixed-side template, which holds a mold 9 for molding a molded product. The runner plate 3 is a member located between the fixed-side mounting plate 1 and the fixed-side template 2. Reference numeral 4 denotes a movable side template, which holds a core 10 for molding a molded product. Reference numeral 5 denotes a spacer block, which is a member for securing an ejector stroke 28 for releasing the molded product molded by the molding unit 11 from the movable mold. Reference numeral 6 denotes a movable side mounting plate, which is a member for mounting the movable mold to the injection molding machine. Reference numeral 7 denotes an ejector plate, and 8 denotes a member below the ejector plate, which is a member for sandwiching and holding the flange portion of the ejector pin 26 for projecting a molded product formed by the forming portion 11. A locating ring 12 is a positioning member for the molding machine and the mold. Reference numeral 13 denotes a sprue bush, which is a member that guides the high-temperature molten resin injected and injected from the nozzle of the molding machine into the mold. Reference numeral 14 denotes a primary sprue portion formed by pouring molten resin into the sprue bushing 13. Reference numeral 15 denotes a secondary sprue portion. Reference numeral 16 denotes a runner portion for flowing resin from the primary sprue portion 14 to the secondary sprue portion 15. Reference numeral 17 denotes an air groove (a) machined in a circumferential shape with respect to a hole into which the sprue bushing 13 of the runner plate 3 is assembled. Reference numeral 18 denotes an air groove (b) provided so as to surround the runner portion 16 of the fixed-side template 2. Reference numeral 19 denotes an air groove (c) provided around the secondary sprue portion 15. Reference numeral 20 denotes an air hole (a) penetrating through the hole into which the sprue bushing 13 enters from the side surface of the fixed side mounting plate 1 and penetrating to the opposite surface. Reference numeral 21 denotes an air hole (b) which penetrates the circumferential groove 17 from the side surface of the runner plate 3 and penetrates to the opposite surface. Reference numeral 22 denotes an air hole (c) provided so as to penetrate the air groove (b) 18. Reference numeral 23 denotes an air hole (d) provided so as to penetrate the air groove (c) 19. Reference numeral 24 denotes a cooling air tube, and reference numeral 25 denotes a joint connecting the mold and the air tube 24.

  The high-temperature molten resin injected from the nozzle of the injection molding machine passes through the sprue bushing 13 and is filled into the molded part 11 of the molded product through the runner part 16 and the secondary sprue part 15. At the time of molding, in order to quickly solidify the high-temperature molten resin, the primary sprue portion 14 is cooled by flowing air from the air holes (a) 20 provided in the fixed-side mounting plate 1 so that the cylinder of the sprue bushing 13 is air-cooled. The crease provided in the cylindrical surface of the primary sprue portion 14 is more effective and shortens the solidification time of the primary sprue portion 14. Further, the root portion of the primary sprue portion 14 is cooled by flowing air from an air hole (b) 21 provided in the runner plate 3. The runner 16 is cooled by the air flowing from the air holes (c) 22 flowing into the air grooves (b) 18 provided around the runner 16 so that the runner 16 is cooled and the solidification time of the runner 16 is shortened. The Cooling of the secondary sprue part 15 flows from the air hole (d) 23 provided in the fixed side mold plate 2 and flows into the air groove (c) 19 provided around the secondary sprue part 15. And the solidification time is shortened.

  2A to 2C show the mold sprue bushing of this embodiment. In the center of the sprue bushing 13, a tapered hole that becomes the primary sprue portion 14 is provided. An air groove (d) 27 is also provided on the outer peripheral surface of the cylinder to enhance the cooling effect. As shown in FIGS. 5 (a) to 5 (c), a modified example 1 in which a fold shape 29 is formed on the outer peripheral surface of the cylinder to enhance the cooling effect can be used, and FIGS. 6 (a) to (c). The air groove (e) 30 in which air is introduced from the base of the sprue bush and extracted from the tip as shown in FIG.

  FIG. 3 shows a runner cooling groove diagram provided on the fixed side mold plate of the mold of this embodiment, and the shortest distance between the runner portion 16 and the air groove (b) provided along the periphery thereof is 0.5. ˜2 mm.

  FIG. 4 is a secondary sprue cooling groove diagram provided in the fixed side mold plate of the mold of this embodiment, and the shortest distance between the secondary sprue 15 and the air groove (c) 19 provided along the periphery thereof. Is 0.5 to 2 mm.

  In the injection mold of the embodiment, the cooling temperature of the mold resin can be controlled by providing a heating means such as a heater in the vicinity of the hole or the recess where the sprue or runner is formed.

An injection molding mold structure employing the cooling method of the present embodiment is shown. The sprue bush (Example 1) used for the injection mold mold of a present Example is shown. It is the figure which showed the runner part cooling groove figure provided in the stationary side template of the injection molding mold die of a present Example, and was seen from the anti-parting surface. It is the figure which showed the secondary sprue part cooling groove provided in the stationary-side mold plate of the injection molding mold of a present Example, and was seen from the parting surface in the state which extracted the cavity 9. FIG. The sprue bushing (modification 1) used for the injection mold mold of a present Example is shown. The sprue bushing (modification 2) used for the injection mold mold of a present Example is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fixed side mounting plate, 2 ... Fixed side type plate, 3 ... Runner plate, 4 ... Movable side type plate, 5 ... Spacer block, 6 ... Moving side mounting plate, 7 ... On ejector plate, 8 ... Under ejector plate, 9 ... Cabinet, 10 ... Core, 11 ... Molding part, 12 ... Locating ring, 13 ... Sprue bushing, 14 ... Primary sprue part, 15 ... Secondary sprue part, 16 ... Runner part, 17 ... Air groove (a), 18 ..Air groove (b), 19 ... Air groove (c), 20 ... Air hole (a), 21 ... Air hole (b), 22 ... Air hole (c), 23 ... Air hole (d), 24 ..Cooling air tube, 25..Fitting, 26..Ejector pin, 27..Air groove (d), 28 Ejector stroke, 29..Flute shape, 30..Air groove (e)

Claims (5)

In a mold consisting of multiple mold members, forming sprue and runner and performing mold injection molding,
At least one of the mold members has a hole or a recess for forming a sprue or a runner, and a cooling air passage is provided in the vicinity of the hole or the recess. In the mold injection mold according to claim 1,
At least one of the mold members is a sprue bush having a hole for forming a sprue, and a groove serving as a cooling air passage is formed on the surface of the sprue bush and in the vicinity of the hole for forming the sprue. A mold injection mold characterized by being provided. In the mold injection mold according to claim 1,
At least one of the mold members is provided with a groove serving as a cooling air passage in the vicinity of a hole or a recess forming a sprue or a runner and in a joint surface with another mold member. Mold injection mold. In the mold injection mold according to claim 3,
A mold injection mold, wherein at least one of the mold members is provided with a groove serving as a cooling air passage along a periphery of a recess forming a runner. In the mold injection mold according to any one of claims 1 to 4,
A mold injection mold characterized by having a heating means in the vicinity of a hole or a recess forming the sprue or runner.

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