JPH04279309A - Structure of die slide type ejector - Google Patents

Abstract

PURPOSE:To enable ejection to be performed without additionally providing any special structures by engaging (n) pieces of pins and an operating material for causing only a primary runner to be projected after the primary injection where the mold is not slid, and engaging 2n pieces of pins and the operating material for causing a secondary runner and an article to be projected after the secondary injection. CONSTITUTION:The leg 214 of an operating material 213 engages with a projecting pin 226 located at a primary runner 223, and the projecting pin 226 is projected and only the primary runner is ejected. When the primary injection is completed, a slide mold 22 is allowed to slide from the first mold clamping position toward upward second mold clamping position. A movable mold 20 is permitted to forward and thus mold-match with the slide mold 22, to thereby allow the half bodies within female molds 201, 221 to be faced to each other, and in such condition, molten resin is injected. Furthermore, molten resin is injected in the cavity of the mold part via a sprue 200, second runner 223 and submarine gate 203, and the facing parts of the half bodies are caused to join, with the result that a hollow article is manufactured.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die slide type ejector structure, and more particularly to a structure that allows ejection without adding any special mechanism to a molding machine.

0002

BACKGROUND OF THE INVENTION When producing synthetic resin products, blow molding or injection molding are generally used.

For example, when manufacturing a hollow product using a blow molding method, the molten resin is extruded into a cylindrical parison using an accumulator head, both sides of the parison are sandwiched between molds, and air is blown into the inside to form the hollow product. In this case, relatively large burrs are formed on the top and bottom of the product due to the mold, and a nozzle hole for blowing air remains on the product, resulting in a completely sealed hollow product. Moreover, it is difficult to manufacture to a uniform thickness.

On the other hand, when manufacturing hollow products using the injection molding method, a method is adopted in which the hollow molded product is divided into two halves, each of which is injection molded, and the two halves are joined by abutting each other. In this case, there is an advantage that completely sealed hollow products and hollow products with complex shapes can be successfully manufactured.

For example, as shown in Japanese Unexamined Patent Publication No. 62-87315, a slide mold is provided between a fixed mold and a movable mold, and the movable mold and the slide mold are placed in the first mold clamping position, and the male and female of both are placed in the first clamping position. A pair of half bodies is manufactured by injecting molten resin into the cavity formed by the mold part, and then the slide mold is slid to set the movable mold and the slide mold to the second mold clamping position, and the half bodies are manufactured. A die slide injection molding method is known in which the two halves are joined by abutting the two halves and injecting molten resin into the abutting portion.

[0006]

However, when constructing this type of injection molding machine, it is necessary to provide the mold with an ejector mechanism in order to eject the product from the mold.

However, in the die slide injection molding method described in the above-mentioned conventional publication, the movable mold and the slide mold are formed with runners that communicate with the male and female mold parts, and two runners are formed at the first and second mold clamping positions. Since the injection is carried out in stages, many different types of runners are created in different mold parts, and if a mechanism to eject each of these runners is provided, the molding machine will become larger and more complicated, which is undesirable. The important thing is how to build it.

[0008] In view of this point, it is an object of the present invention to provide a die slide type ejector structure that allows ejection without adding any special mechanism.

[0009]

[Means for Solving the Problems] Therefore, a die slide type ejector structure according to the present invention is a die slide injection molding type mold structure having a slide mold that moves relatively between a fixed mold and a movable mold. When the number of male and female mold parts is n, the sliding mold is provided with 3n protruding pins slidably in the mold opening direction, the fixed mold is provided with 2n operating members with legs, and the mold is slidable. After the primary injection, the n pins and the operating member engage to project only the primary runner, and after the secondary injection after sliding the mold, the n pins and the operating member engage with each other so as to project the secondary runner and the product. The gist is that 2n pins different from n are engaged with the operating member.

The present invention is highly effective when applied to a mold in which the slide mold slides linearly as shown in Japanese Patent Application Laid-Open No. 62-87315, but when the slide mold rotates, it The present invention can also be applied to a die slide type ejector structure in which split bodies are manufactured and half bodies are joined. That is, sliding type relative movement includes both linear sliding and rotation.

[0011]

[Operation] When the slide mold and movable mold are matched and molten resin is injected, the molten resin is injected into the cavity of the mold part through the primary runner to produce a half body, and the movable mold is opened. When the operating member is actuated, the pin engaged with the leg of the operating member is operated to eject only the primary runner.

Next, the slide mold is relatively moved, the movable mold is matched, the halves are brought into contact, and the molten resin is injected into the cavity of the mold part through the secondary runner. , the abutting portions of the halves are welded together.

[0013] At this time, a pin is selected by the slide of the mold and engaged with the foot, and when the operating member is actuated, the selected pin is operated and the secondary runner and the product are ejected.

[0014] Since the ejecting pin is selected using the sliding motion of the mold in this way, there is no need to provide a mechanism dedicated to the primary eject and secondary eject, and the eject mechanism is extremely simple. .

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below based on specific examples shown in the drawings.

FIGS. 1 to 3 show a die slide type ejector structure according to an embodiment of the present invention. In the figure, a mounting frame 11 is provided on a bed 10 of an injection molding machine 1, a die slide type mold 2 is supported on the mounting frame 11, and a molten resin injection mechanism 3 is mounted on the bed 10. Disposed facing the mold 2, the injection mechanism 3 includes a hopper 30 for storing molten resin, a nozzle 31 for injecting the molten resin, a pressure cylinder 32, and a drive device 33 for moving the nozzle 31 forward and backward. .

On the other hand, the mold 2 has a slide mold 22.
Die slide cylinder 2 that slides the die in the vertical direction
3 is provided, and a mold opening/closing cylinder 24 for opening and closing the movable mold 20 is also provided.

Next, the structure of the mold 2 will be explained in detail. The mold 2 is constructed by disposing a slide mold 22 between a movable mold 20 and a fixed mold 21. A sprue 200 is bored in the movable mold 20 so as to communicate with the mold cutting surface, and a female mold part 201 and a male mold part 202 are formed in the mold cutting surface of the movable mold 20, and the female mold part 201 A submarine gate 203 communicating with the mold is provided, and a mold relief portion 204 is recessed.

On the other hand, the sliding mold 22 has a female mold part 221 and a female mold part 221 on the mold cutting surface of the slide mold 22 that are matched with the mold parts 201 and 202 on the movable mold 20 side to form a half-shaped cavity that is divided into two parts. A male mold part 222 is formed, and a runner 223 for supplying molten resin to the male and female mold parts 221 and 222 is formed on the mold cutting surface of the slide mold 22, and a submarine gate 224 communicating with the female mold part 221 is formed. and side gates are formed. The slide mold 22 also has a pin hole 225 that communicates with the female mold part 221 and the runner 223.
Three protruding pins 22 are provided in the pin holes 225.
6 is housed so that it can freely appear and retract in the mold opening direction, and is prevented from coming out.
The protruding pin 225 is biased in the retracting direction by a spring member 227, and a foot release portion 2 is provided on the back side of the slide mold 22.
28 is recessed.

The fixed mold 21 is fixed to a mounting plate 210, and the fixed mold 21 has two holes 211 for operating pins, and an operating member 213 is provided between the fixed mold 21 and the mounting plate 212. is provided, and the operating member 213 has two legs 21.
4 is formed, and the foot 214 is slidably housed in the pin operation hole 211 and can be engaged with the ejection pin 225, and the ejection pin 225 and the operation member 21
3 constitutes an eject mechanism.

Next, the functions and effects will be explained.

When manufacturing a hollow product, the slide mold 22 is first set at the first mold clamping position, the movable mold 20 is advanced by the mold opening/closing cylinder 24, the molds are aligned as shown in FIG. The male and female mold parts 201, 222, 221, and 202 of the mold 20 and the slide mold 21 form a half-shaped cavity in which the product is divided into two, and in this state, the drive device 33 is operated to move the nozzle 31 forward. Then, the pressurizing cylinder 32 is operated and the molten resin in the hopper 30 is injected. Then the molten resin sprue 200
, primary runner 223 and submarine gate 203,
It is injected into the cavity of the mold part via 224 to produce the halves.

When the half body is manufactured, the nozzle 31 is retracted, the mold opening/closing cylinder 24 is activated to open the movable mold 20, and the operating member 213 is activated. Then, the foot 214 of the operating member 213 is engaged with the ejector pin 226 located on the primary runner 223, and the ejector pin 2
26 is ejected and only the primary runner is ejected,
The molded half bodies are held within the female mold parts 201 and 221 of the movable mold 20 and the slide mold 22.

When the primary injection is completed in this way, the slide mold 22 is slid from the first mold clamping position to the upper second mold clamping position, and the movable mold 20 is advanced to move the slide mold 22 as shown in FIG. 22, the female mold parts 201 and 2
When the halves in 21 are brought together and the molten resin is injected in that state, the molten resin flows through the sprue 200 and the secondary runner 2.
23 and the submarine gate 203 into the cavity of the mold part, and the abutting parts of the halves are joined to produce a hollow product.

When the joining of the halves is completed, the nozzle 31 and movable mold 20 are moved back again to perform ejection, but at this time, the slide mold 22 slides to position the secondary runner 223 and the female mold part 221. The two protruding pins 226 are selected and the two legs 21 of the operating member 213 are
4, and when the operating member 213 is actuated, the selected ejector pin 226 will protrude and the secondary runner and product will be ejected.

In the ejector structure of this embodiment as described above, the sliding movement of the slide mold 22 is used to select the engagement between the leg 214 of the operating member 213 and the ejecting pin 226, and thereby to eject the primary eject and the secondary eject. Since this is done, there is no need to add special mechanisms such as primary-only and secondary-only ejector mechanisms to the injection molding machine 1, and the molding machine 1 can be prevented from becoming large and complicated.

[0027]

As described above, according to the die slide type ejector structure according to the present invention, after the primary injection without sliding the mold, the ejector pin provided on the slide mold and the foot of the operating member provided on the fixed mold are removed. By engaging the two, only the primary runner is projected, while after the secondary injection after sliding the mold, the secondary runner and the product are projected by engaging a pin and an operating member different from those mentioned above. This has the effect of reliably producing the desired ejection without adding any special mechanism to the molding machine.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing a die slide type injection molding machine having an ejector structure according to an embodiment of the present invention.

FIG. 2 is a sectional view showing the state of the ejector structure during primary injection.

FIG. 3 is a sectional view showing the state of the ejector structure during secondary injection.

[Explanation of symbols]

1 Injection molding machine
20 Movable type 21 Fixed type
213 Operation member 214 Leg
22 Slide mold 221 Female mold part
222 Male part 226 Ejection pin

Claims (1)

[Claims] 1. In a mold structure of a die slide injection molding method having a slide mold 22 that moves relatively between a fixed mold 21 and a movable mold 20, the number of a pair of male and female mold parts 221 and 222 of the slide mold 22 is n. When , slide type 2
2 is provided with 3n protruding pins 226 slidably in the mold opening direction, and the fixed mold 21 is provided with an operating member 213 with 2n legs 214, so that only the primary runner is protruded after the primary injection without sliding the mold. After the secondary injection after sliding the mold, 2n pins different from the above n pins are inserted to project the secondary runner and the product. A die slide type ejector structure characterized in that 226 and the operating member 213 engage with each other.