JP2002307490A - Molding system for resin molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding system capable of continuously molding a molded product not only to shorten a molding cycle time but also to enhance productivity. SOLUTION: The molding system consists of a hot runner block 16 having a resin passage 13 through which a molten resin flows, a molding part 18 having a molding unit provided on the way of the resin passage to mold the flowing molten resin to obtain the molded product, cooling parts 33 and 34 for cooling the molded product molded in the molding unit and a moving means for moving the molded product molded in the molding unit to the cooling parts 33 and 34 to cool the same. The molding unit is constituted of a resin clamping spindle 19 for chucking the molten resin flowing through the resin passage, a pressure molding spindle 26 for molding the chucked molten resin under pressure and the cavity provided to the end surface of the pressure molding spindle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molding product molding system suitable for molding small molded products.

[0002]

2. Description of the Related Art In an injection molding die for molding a resin molded product having the same shape, a cavity is generally formed between a fixed die and a movable die. A resin injection port is provided in the stationary mold, and the resin injection port communicates with the cavity by a hot runner. A gate valve is provided between the end of the hot runner and the cavity, and the cavity is filled with the molten resin by opening the gate valve. Further, a cooling water passage is provided around the cavity, and the molten resin filled in the cavity is cooled and solidified.

[0003] In a multi-cavity molding die for simultaneously molding a plurality of molded products with one injection molding die, a plurality of cavities are provided, and a hot runner is branched and provided in each cavity. The molten resin injected from the resin injection port is distributed by the hot runner and is filled in each cavity.

[0004]

When a molded article is molded by the injection mold having the above-described structure, the fixed mold and the movable mold are clamped, and then melted from the injection molding machine. The resin is injected into the cavity through the resin injection port, and waits for the molten resin in the cavity to be cooled and solidified. Then, after the molten resin is cooled and solidified, the fixed mold and the movable mold are released from the mold and the molded product is taken out, and there is a problem that the molding cycle time is long.

[0005] In addition, the size of a molded product formed by an injection molding die is limited, and it is impossible to form a small molded product of several millimeters.

The present invention has been made in view of the above circumstances. It is an object of the present invention to be able to continuously mold even a minute molded product, to shorten the molding cycle time, and to improve the productivity. It is an object of the present invention to provide a resin molded product molding system capable of improving the quality.

[0007]

To achieve the above object, according to the present invention, there is provided a hot runner block having a resin passage through which molten resin flows, and a hot runner block provided in the middle of the resin passage and flowing through the resin passage. A molding section having a molding unit for molding a molded article with a resin, a cooling section for cooling the molded article molded by the molding unit, and moving means for moving the cooling section to the molding section to cool the molded article. Become
The molding unit is provided with a pair of resin clamp spindles which are provided to be able to advance and retreat in a direction crossing the resin passage and chuck the molten resin flowing through the resin passage, and are independent of the resin clamp spindle inside the resin clamp spindle. Resin molding, comprising: a pair of pressure molding spindles which are provided so as to be able to advance and retreat and pressure-mold the chucked molten resin, and a cavity provided at an end face of the pressure molding spindle. Product molding system.

A second aspect of the present invention is a hot runner block having a resin passage through which a molten resin flows, a molding section provided in the middle of the resin passage, and having a molding unit for molding a molded article with the flowing molten resin, A cooling unit that cools the molded product formed by the unit; and a moving unit that moves the cooling unit to the molding unit to cool the molded product, wherein the molding unit is capable of moving forward and backward in a direction crossing the resin passage. A pair of resin clamp spindles for chucking the molten resin flowing through the resin passage, a cavity provided on at least one end face of the resin clamp spindle, and the resin clamp spindle provided independently and freely movable back and forth. And a pressure molding spindle for pressure molding the molten resin in the cavity. In the goods molding system.

According to a third aspect of the present invention, the resin passage according to the first or second aspect has a receiving portion for the molten resin injected from a resin injection portion for injecting the molten resin, so that the excess molten resin which has passed through the molding unit can be removed. It is a molten resin circulation path for refluxing to the resin injection section.

According to a fourth aspect of the present invention, in the first or second aspect, the cooling section has a cooling block having a cooling water passage, and air is injected into the molded article provided in the cooling block to drop the molded article from the ejection pin. And an air nozzle.

According to a fifth aspect of the present invention, the pressure forming spindle according to the first aspect comprises a pair of spindles having concave portions forming cavities on opposite end faces, and the end faces of the spindles are brought into contact with each other to temporarily transfer the molten resin. After the pressurization, a drive mechanism for increasing the density of the molten resin by performing a second pressurization is provided.

According to the above construction, a part of the molten resin flowing through the resin passage is chucked by the pair of resin clamp spindles, and the chucked molten resin is pressed and molded by the pair of pressure molding spindles having cavities. Then, the molded article can be continuously moved to the cooling section and cooled.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show a first embodiment, and FIG.
1 is a perspective view schematically showing an entire configuration of a molding system for a resin molded product. As shown in FIG. 1, the molding system 1 is provided with a slide unit 2 that is movable in the left-right direction (the direction of the arrow X). A first moving means fixed to the base 1 or the like is provided at one end of the slide unit 2 in the left-right direction.
Are connected, and the slide unit 2 moves in the left-right direction.

Upright walls 4a and 4b are provided at both left and right ends of the slide unit 2, and a recess 5 is formed between the upright walls 4a and 4b of the slide unit 2. The recess 5 is provided with a manifold block 6 in a direction orthogonal to the slide unit 2, which is horizontally supported by a plurality of columns 7.

Rails 8 are provided on both sides along the longitudinal direction of the slide unit 2 in the left-right direction. The rails 8 are supported by rail support blocks 9 provided on the manifold block 6. The slide unit 2 moves with respect to the manifold block 6.

The structure of the manifold block 6 will be described with reference to FIGS. That is, a resin injection port 10 as a receiving portion is provided on an end surface at an intermediate portion in the width direction of the manifold block 6. The resin injection port 10 is provided with a nozzle touch surface 10a to which the nozzle 12 of the resin injection cylinder 11 is joined. The resin inlet 13 is provided with a resin passage 13 through which the molten resin a flows.

The resin passage 13 has a lower passage 13a extending laterally in the vicinity of a lower portion of the manifold block 6, and a rising passage 13 extending vertically from the end of the lower passage 13a.
b and an upper passage 13c extending laterally from the end of the ascending passage 13b near the upper portion of the manifold block 6.
And a descending passage 13d extending vertically from the end of the upper passage 13c.

An opening / closing valve 14 is provided in the descending passage 13d, and a nozzle 14a of the opening / closing valve 14 communicates with the resin injection cylinder 11. Therefore, the resin passage 13 is formed as a circulation path for circulating the molten resin a. further,
A heater 15 is embedded in both sides of the resin passage 13 and around the opening / closing valve 14 to form a hot runner block 16.

The resin passage 13 is a long hole whose cross section is flat in the vertical direction.
Is formed. That is, a resin clamp spindle 19 constituting the molding unit 17 is provided between the rising walls 4a and 4b of the slide unit 2. This resin clamp spindle 19 is used for the resin passage 1.
3 is a cylindrical pipe having an outer diameter smaller than the vertical dimension of the resin clamp spindle 19 and the outer circumferential surface of the resin clamp spindle 19.
A space 13e through which the molten resin a can flow is provided between the inner periphery of both ends of the housing 3 and the inner periphery of the housing 3.

The resin clamp spindle 19 is
, And the base ends of the two portions are rising walls 4a and 4b.
Are slidably fitted in the support hole 20 provided in the axial direction. A first cylinder 21 communicating with the support hole 20 is provided on the rising walls 4a and 4b, and a first piston 22 is provided inside the first cylinder 21 so as to be movable in the axial direction of the resin clamp spindle 19. Have been.

A flange 19a is provided at the base end of the resin clamp spindle 19, and the flange 19a is directly connected to a first piston 22 as a drive mechanism by a fixing ring 23 and a bolt 24. The first cylinder 21 is divided into a front chamber 21 a and a rear chamber 2 by a first piston 22.
The front chamber 21a and the rear chamber 21b are connected to an air supply source (not shown) via air ports 25a and 25b, respectively. Then, the resin clamp spindle 19 advances and retreats by the first piston 22, and the end face thereof comes into contact with and separates from the molded portion 18.

A pressure forming spindle 26 which can be independently advanced and retracted is inserted inside the resin clamp spindle 19. The pressure forming spindle 26 is a thick cylindrical pipe, in which a protruding pin 27 is independently inserted so as to be able to advance and retreat.

The pressure forming spindle 26 and the protruding pin 27 are also divided into two parts at an intermediate portion, and a cavity 28 is formed at the end faces of the pressure forming spindle 26 facing each other.
The end faces of the protruding pins 27 facing each other can hold the molded product b.

The base end of the pressure forming spindle 26 passes through the first cylinder 21 and the first piston 22. A second cylinder 2 is provided inside the first piston 22.
The second cylinder 29 is provided with a second piston 30 as a drive mechanism movably in the axial direction of the pressure forming spindle 26.

At the base end of the pressure forming spindle 26, a flange 26a is provided.
The piston 30 is directly connected. Second cylinder 29
Are the front chamber 29a and the rear chamber 29b by the second piston 30.
The front chamber 29a and the rear chamber 29b are connected to an air supply source (not shown) via air ports 31a and 31b, respectively. Then, the second piston 30
As a result, the pressure forming spindle 26 advances and retreats, and the end faces forming the cavity 28 come into contact with and separate from each other.

Further, the base end of the protruding pin 27 is
And protrudes outside through the piston 30, and the protruding pin 27 is connected to an air cylinder (not shown). Then, the protruding pin 27 is advanced and retracted by the air cylinder, so that the molded product b can be pinched or released.

On the left and right sides of the manifold block 6, first and second resin clamp spindles 19 are fitted.
And second cooling units 33 and 34. The first and second cooling units 33 and 34 are provided with a ring-shaped cooling block 35.
And is fixed to the manifold block 6 by bolts 36.

The cooling block 35 is provided with an air nozzle 37 facing the molded product b at an upper portion with the molding unit 17 interposed therebetween, and a lower portion 3 for dropping the molded product b at a lower portion.
8 are provided. The cooling block 35 has a cooling water passage 3
9 is provided to forcibly cool and solidify the molded article b.

Next, the operation of the molding system 1 configured as described above will be described.

When molten resin a such as polypropylene is injected from the nozzle 12 of the resin injection cylinder 11, the molten resin a flows through the resin passage 13 of the hot runner block 16.

In this state, when air is supplied from the air port 25b to the rear chambers 21b of the pair of left and right first cylinders 21, the first piston 22 moves forward by the air pressure. Therefore, the resin clamp spindle 1
When the end faces abut as shown in FIG. 4A, the molten resin a flowing through the resin passage 13 is chucked. That is, since the resin clamp spindle 19 has a pipe shape, a part of the molten resin a flowing through the resin passage 13 is taken into the resin clamp spindle 19 at the same time when the end face abuts. At this time, the molten resin a outside the resin clamp spindle 19 is
The resin flows through the resin passage 13 via 3e.

Immediately after the forward movement of the resin clamp spindle 19, when air is supplied from the air port 31b to the rear chamber 29b of the pair of left and right second cylinders 29, the second piston 30 moves forward by the air pressure. . Accordingly, each of the pressure forming spindles 26 advances, and the ejection pin 27 advances by the second air cylinder 32.

Therefore, the molten resin a taken in by the resin clamp spindle 19 is
And the inside of the cavity 28 formed by the end face of the protruding pin 27 and the first pressurization is performed. In this state, as shown in FIG. 4A, there is a slight gap g between the pressure molding spindle 26 and the molten resin a, but the second piston 30 further advances and the resin clamp spindle 19 is moved. When the second pressurization is performed for a stroke corresponding to the gap g, the resin density in the cavity 28 increases, and a molded product b suitable for high-density and fine precision parts is formed.

Next, the first cylinder 3 is driven to move the slide unit 2 to the left. Then, the molded product b sandwiched between the end faces of the pressure forming spindle 26 and the protruding pin 27 faces the cooling block 35 of the first cooling unit 33. Since the cooling block 35 is constantly cooled by the cooling water flowing through the cooling water passage 39, the molded article b is forcibly cooled.

Next, when air is supplied from the air ports 25a and 31b to the front chamber 21a of the pair of left and right first cylinders 19 and the front chamber 29a of the second cylinder 29, the first piston is driven by the air pressure. 22 and the second piston 30 are retracted. Therefore, since the resin clamp spindle 19 and the pressure forming spindle 26 are respectively retracted, as shown in FIG.
7.

Then, the air injected from the air nozzle 37 is blown onto the molded product b. When the ejection pin 27 is retracted by the air cylinder, the molded product b held by the end face of the ejection pin 27 is separated from the ejection pin 27 by the pressure of the air and falls from the drop port 38.

At this time, the resin passage 1 in the molding portion 18
Since 3 is blocked by the outer peripheral wall of the resin clamp spindle 19, the molten resin a does not flow into the molding section 18. The resin passage 13 is composed of a lower passage 13a, an ascending passage 13b, an upper passage 13c, and a descending passage 13d. By opening, the molten resin a can be returned to the resin injection cylinder 11.

When the cooling of the molded product b is completed, the first air cylinder 3 is driven again to move the slide unit 2 rightward, and the molding portion 18 is formed at the abutting portion of the resin clamp spindle 19 and the pressure molding spindle 26. As described above, a part of the molten resin a flowing through the resin passage 13 is taken into the resin clamp spindle 19 and molded by the pressure molding spindle 26.

FIG. 5 shows a second embodiment, and is a cross-sectional view showing a state where pressure is applied by a pressure forming spindle. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In this embodiment, a pair of pressure forming spindles 2
The molding block 40 is embedded in the end faces facing each other of 6,
An arc-shaped concave portion 41 is formed in the end faces of the molding block 40 facing each other to form, for example, a lens molding cavity 4.
2 is formed. Further, in the resin clamp spindle 19, when taking in the molten resin a, the pair of resin clamp spindles 19 simultaneously advance and their end faces abut each other. By shutting off the molten resin a, the resin clamp spindle 19
Burr can be prevented from being generated between the end faces.

FIG. 6 shows a third embodiment, in which the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. FIG. 6A is a cross-sectional view showing a state where molten resin is taken in by a resin clamp spindle, and FIG. 6B is a cross-sectional view showing a state where pressure is applied by a pressure forming spindle.

In this embodiment, one of a pair of resin clamp spindles 44 is provided with, for example, an arc-shaped cavity 45 and a protruding pin 27 for molding a lens, and the other is provided with a pressure forming spindle 46 and a protruding pin 27. Things. Cavity 45 of pressure forming spindle 46
A flat surface is formed on the end face facing the.

According to the present embodiment, the resin clamp spindle 44 is configured such that when the molten resin a is taken in, the pair of resin clamp spindles 44 simultaneously advance and their end faces abut each other. The molding spindle 46 advances in the direction of the cavity 45 to press-mold the molten resin a, thereby molding the resin. Thus, the resin density in the cavity 46 can be increased.

In the above-described embodiment, the slide block, the resin clamp spindle, the pressure molding spindle and the protruding pin are driven by the air cylinder. However, for example, the position is detected by a servomotor and driven. The driving source is not limited.

Further, since the pressure forming spindle having the cavity is replaceable, a forming system for forming a molded product having a different shape can be constituted.
Significant cost reduction can be achieved as compared with a conventional injection mold.

[0046]

As described above, according to the present invention, a part of the molten resin flowing through the resin passage is chucked by the pair of resin clamp spindles, and the chucked molten resin is transferred to the pair of clamps having the cavity. Since the molded product is moved to the cooling part and cooled by pressing with the pressure molding spindle, the molded product can be continuously molded, shortening the molding cycle time and improving productivity. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view of an entire molding system according to a first embodiment of the present invention.

2A and 2B show the same embodiment, in which FIG. 2A is a side view of a manifold block, and FIG. 2B is a cross-sectional view taken along line AA.

FIG. 3 shows the same embodiment, and is a vertical side view of a slide block and a manifold block.

FIGS. 4A and 4B show the same embodiment, in which FIG. 4A is a longitudinal side view of a molding section, and FIG.

FIG. 5 shows a second embodiment of the present invention, and is a longitudinal side view of a molded portion.

FIG. 6 shows a third embodiment of the present invention, in which (a)
(B) is a vertical sectional side view of a molding part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Molding system 13 ... Resin passage 16 ... Hot runner block 17 ... Molding unit 18 ... Molding part 19 ... Resin clamp spindle 26 ... Pressure molding spindle 27 ... Protrusion pin 33, 34 ... Cooling part

Continued on the front page F term (reference) 4F202 AA11 CA11 CB01 CK01 CK03 CK07 CK18 CK42 CK52 CK74 CK90 CM02 CM08 CN01 CN05 4F206 AA11 JA07 JN14 JN15 JN25 JN41 JN43 JQ81

Claims (5)

[Claims] 1. A hot runner block having a resin passage through which a molten resin flows, a molding unit provided in the middle of the resin passage and having a molding unit for molding a molded product by the flowing molten resin, and a molding unit formed by the molding unit. A cooling unit that cools the molded product, and a moving unit that moves the cooling unit to the molding unit to cool the molded product. The molding unit is provided so as to be able to advance and retreat in a direction crossing the resin passage. A pair of resin clamp spindles for chucking the molten resin flowing through the resin passage; and a pressure molding of the chucked molten resin provided inside the resin clamp spindle so as to be able to advance and retreat independently of the resin clamp spindle. A pair of pressure forming spindles, and a cavity provided on an end face of the pressure forming spindle. Molding system for plastic molded products. 2. A molding section having a hot runner block having a resin passage through which a molten resin flows, a molding section provided in the middle of the resin passage, and having a molding unit for molding a molded article with the flowing molten resin, and molding by the molding unit. A cooling unit that cools the molded product, and a moving unit that moves the cooling unit to the molding unit to cool the molded product. The molding unit is provided so as to be able to advance and retreat in a direction crossing the resin passage. A pair of resin clamp spindles for chucking the molten resin flowing through the resin passage, a cavity provided on at least one end face of the resin clamp spindle, and the resin clamp spindle independently provided so as to be able to advance and retreat. And a pressure molding spindle for pressure molding the molten resin in the cavity. Shape system. 3. The molten resin has a receiving portion for receiving the molten resin injected from a resin injection portion for injecting the molten resin, and the excess molten resin having passed through the molding unit is returned to the resin injection portion. The molding system for a resin molded product according to claim 1, wherein the molding system is a circulation path. 4. The cooling section includes: a cooling block having a cooling water passage; and an air nozzle provided in the cooling block, which injects air to the molded product and drops the molded product from the ejection pin. The resin molding product molding system according to claim 1 or 2, wherein: 5. The pressure-forming spindle comprises a pair of spindles having concave portions forming cavities on end faces facing each other, and the end faces of the spindles are abutted to each other to first pressurize the molten resin, and then to pressurize the molten resin. The molding system for a resin molded product according to claim 1, further comprising a drive mechanism for increasing the density of the molten resin by applying pressure.