JP2004230723A - Injection molding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To mold a molding with a definite good quality by always filling a definite amount of a molding material in a cavity by decreasing flow resistance in a passage for the molding material. <P>SOLUTION: A hot nozzle 14 provided in a fixed mold 3 and having through-holes 19 and 22 communicated with the cavity, a sprue 33 provided on a part of the fixed mold 3 above the hot nozzle 14 and having a through-hole 36 communicated with an injection nozzle on an upper part of the fixed mold 3, and a manifold 26 provided on a part of the fixed mold 3 between the hot nozzle 14 and the sprue 33 and having a through-hole 28 communicating the through-holes 19 and 22 of the hot nozzle 14 with the through-hole 36 of the sprue 33, are provided. A series of passages 44 for the molding material are formed by the through-holes 19 and 22 of the hot nozzle 14, the through-hole 28 of the manifold 26 and the through-hole 25 of the sprue 33, and a part of the through-hole 28 of the manifold 26 constituting the passage 44 for the molding material is formed into approximately a straight line. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an injection molding apparatus, and particularly to an injection molding apparatus having a hot runner mold.
[0002]
[Prior art]
As an example of this type of injection molding apparatus, as shown in FIG. 3, a fixed mold 51 and a movable mold 52 are provided so as to be relatively openable. A molding die for forming the cavity 53 between the two dies, a hot nozzle 56 provided in the fixed die 51 and having a through hole 56a communicating with the cavity 53, and a valve 57 for opening and closing the through hole 56a of the hot nozzle 56 And a sprue 58 provided at a fixed mold portion obliquely above the hot nozzle 56 and having a through hole 58a communicating with an injection nozzle located above the fixed mold, and between the hot nozzle 56 and the sprue 58. And a manifold 59 having a through hole 60 communicating the through hole 56a of the hot nozzle 56 and the through hole 58a of the sprue 58. It is known that a series of molding material passages from the injection nozzle to the cavity are formed by the through hole 56a of the nozzle 56, the through hole 60 of the manifold 59, and the through hole 58a of the sprue 58 (for example, see Patent Reference 1).
[0003]
[Patent Document 1]
JP-A-2000-025072 (page 1, FIG. 3)
[0004]
[Problems to be solved by the invention]
By the way, in the injection molding apparatus having the above-described configuration, the through hole 60 of the manifold 59 has a vertically oriented upper through hole 60a communicating with the through hole of the sprue 58, and a hot nozzle It is formed in the shape of a crank including a lower through-hole 60b extending in the vertical direction communicating with the 56 through-holes 56a, and a middle through-hole 60c communicating the upper through-hole 60a and the lower through-hole 60b in the horizontal direction. For this reason, depending on the type of the molding material, the flow resistance at the corner of the through hole formed at a substantially right angle increases, and the molding material stagnates at that portion, so that a predetermined amount of the molding material is injected into the cavity. Filling becomes difficult, and it becomes difficult to mold a molded article of a certain good quality.
[0005]
The present invention has been made in view of the above-described conventional problems, and reduces the flow resistance in the through-hole of the manifold so that the flow of the manifold can be reduced regardless of the type of molding material used. Injection molding equipment that can reliably inject a predetermined amount of molding material into the cavity without molding material stagnating in the middle of the hole, and mold molded products of constant high quality The purpose is to provide.
[0006]
[Means for Solving the Problems]
The present invention employs the following means in order to solve the above problems. That is, the invention according to claim 1 has a fixed mold and a movable mold that are relatively openably provided in a mold, and forms a cavity between the molds when the molds are clamped. A mold, a hot nozzle provided in the fixed mold and having a through hole communicating with the cavity, and a hot nozzle provided diagonally above the hot nozzle and located at an upper portion of the fixed mold. A sprue having a through-hole communicating with the injection nozzle to be provided, and a through-hole provided at a portion of a fixed mold between the hot nozzle and the sprue, and communicating between the through-hole of the hot nozzle and the through-hole of the sprue. A manifold having holes, wherein a through-hole of the hot nozzle, a through-hole of the manifold, and a through-hole of the sprue form a series of molding material passages from the injection nozzle to the cavity. In the injection molding apparatus, characterized in that the formation of the through hole of the manifold in a substantially linear shape.
According to the injection molding apparatus of the present invention, when the molding material is supplied from the injection nozzle to the molding material passage of the fixed mold, the molding material is supplied through the through hole of the sprue, the through hole of the substantially linear manifold, and the hot nozzle. It flows through the through hole and is injected and filled into the cavity. In this case, since the through hole of the manifold is formed in a substantially linear shape, the molding material does not stay in the through hole of the manifold.
[0007]
The invention according to claim 2 is the injection molding apparatus according to claim 1, wherein the through hole of the manifold is inclined at a gentle angle, and the lower end portion of the through hole is bent so that the hot nozzle is formed at that portion. And a communication part whose inclination is equal to the upper end part of the through hole.
According to the injection molding apparatus of the present invention, when the molding material is supplied from the injection nozzle to the molding material passage of the fixed mold, the molding material is supplied to the through hole of the sprue, the substantially linear manifold inclined at a gentle angle. It flows through the through hole and the through hole of the hot nozzle, and is injected and filled into the cavity. In this case, since the lower end of the through hole of the manifold is provided with a communicating portion whose inclination matches the upper end of the through hole of the hot nozzle, the through hole on the manifold side and the through hole on the hot nozzle side are linearly connected. And the flow resistance can be prevented from increasing in the communicating portion between the two through holes.
[0008]
The invention according to claim 3 is the injection molding apparatus according to claim 1 or 2, wherein the lower end portion of the sprue communicates with the upper communication portion having an inclination that matches the through hole of the sprue, and the communication portion. In addition, there is provided an attachment having a communication hole formed of a through hole of the manifold and a lower communication portion whose inclination coincides with the manifold.
According to the injection molding apparatus of the present invention, when the molding material is supplied from the injection nozzle to the molding material passage of the fixed mold, the molding material is supplied through the through hole of the sprue, the through hole of the substantially linear manifold, and the hot nozzle. It flows through the through hole and is injected and filled into the cavity. In this case, since the communication hole on the attachment side and the communication hole on the manifold side are linearly communicated, the flow resistance is increased at the communication portion between the communication hole on the attachment side and the communication hole on the manifold side. Can be prevented.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention shown in the drawings will be described.
1 and 2 show an embodiment of an injection molding apparatus according to the present invention. The injection molding apparatus 1 includes a fixed mold 3 and a movable mold which are relatively openably provided in a mold clamping mold. A molding die 2 having a mold (not shown); a hot nozzle 14 provided in the fixed die 3; a valve 48 for opening and closing the hot nozzle 14; an actuator 46 for driving the valve 48; A sprue 33 is provided at a portion of the fixed mold 3 that is obliquely upward, and a manifold 26 is provided at a portion of the fixed mold 3 between the hot nozzle 14 and the sprue 33.
[0010]
The fixed mold 3 and the movable mold of the molding mold 2 are attached to a mold clamping mechanism (not shown) of the injection molding apparatus 1, and the movable mold is moved relative to the fixed mold 3 by the operation of the mold clamping mechanism. By relatively moving, the mold clamping mold opening is performed.
[0011]
The fixed mold 3 is configured by combining a plurality of molds. In the present embodiment, the first mold 4 and the second mold 7 located above the first mold 4 are arranged. And a third template 9 located above the second template 7 and a fourth template 11 located above the third template 9.
[0012]
The first template 4 is provided with a cavity 5 penetrating on the lower surface side of the first template 4, and the second template 7 is a cavity communicating with the upper end opening of the cavity 5 of the first template 4. A hot nozzle 14 is mounted in the cavity 5 of the first template 4 and the cavity 8 of the second template 7.
[0013]
The third template 9 is provided with a cavity 10 communicating with an upper end opening of the cavity 8 of the second template 7, and the lower end of the fourth template 11 is the upper end of the cavity 10 of the third template 9. A cavity 12 communicating with the opening and having an upper end penetrating the upper surface of the fourth template 11 is provided, a manifold 26 is provided in the cavity 10 of the third template 9, and an empty space of the fourth template 11 is provided. A sprue 33 is provided in the place 12.
[0014]
As shown in FIG. 2, the hot nozzle 14 is provided on a substantially cylindrical hot nozzle body 15 whose peripheral surface is formed in two steps of a small diameter portion 16 and a large diameter portion 17, and provided on the upper surface side of the hot nozzle body 15. And a guide bush 20 having a substantially frusto-conical shape fitted into the recess 18 having a substantially frusto-conical shape. As shown in FIG. Is formed in the cavity 5 so that a predetermined gap is formed between the inner surface of the space 5 and the inner surface of the space 5.
[0015]
At the center of the hot nozzle body 15, a lower through hole 19 penetrating the hot nozzle body 15 in the up-down direction (vertical direction) is provided, and a lower end opening of the lower through hole 19 is a through hole of the first mold plate 4. 6.
[0016]
At the center of the guide bush 20, a valve insertion hole 21 penetrating the guide bush 20 in the up-down direction (vertical direction) is provided. The lower end of the valve insertion hole 21 is located at the upper end of the lower through-hole 19 of the hot nozzle body 15. It is designed to communicate.
[0017]
An upper through-hole 22 that penetrates obliquely between the upper end of the lower through-hole 19 of the hot nozzle body 15 and the upper surface of the guide bush 20 is provided in a portion of the guide bush 20 outside the valve insertion hole 21. The through hole 23 of the hot nozzle 14 is configured by the upper through hole 22 and the lower through hole 19 of the hot nozzle body 15.
[0018]
The upper through hole 22 of the guide bush 20 is configured such that its center line forms a predetermined angle θ (about 30 degrees in this embodiment) with the center line of the valve insertion hole 21.
[0019]
The upper end opening of the through hole 23 of the hot nozzle 15 is largely hollowed in a hemispherical shape, and the hot nozzle 15 and the manifold 26 thermally expand, so that the through hole 23 of the hot nozzle 15 and the through hole 28 of the manifold 26 described later. When the deviation occurs, the area of the communicating portion between the two through holes 23 and 28 is reduced to prevent the flow resistance from increasing.
[0020]
Heaters 24 and 25 are provided around the small-diameter portion 16 and the large-diameter portion 17 of the hot nozzle body 15, respectively. The heaters 24 and 25 heat the molding material flowing through the through holes 23 of the hot nozzle 14. It has become so.
[0021]
The manifold 26 has a plate shape provided in the space 10 of the third template 9 so that a predetermined gap is formed between the manifold 26 and the inner surface thereof. In a portion corresponding to the insertion hole 21, a valve insertion hole 27 is provided in a state in which the center line is aligned and vertically penetrated, and a portion corresponding to the upper through hole 22 of the guide bush 20 is provided with a through hole. 28 are provided so as to penetrate obliquely in the vertical direction.
[0022]
The through hole 28 of the manifold 26 supplies the molding material from the sprue 33 to the hot nozzle 14 side, and is formed in a substantially straight line from the upper end opening to the lower end opening.
[0023]
The upper end of the through hole 28 of the manifold 26 communicates with the lower end of a through hole 42 of a sprue 33 described later. A lower end portion of the through hole 28 of the manifold 26 is bent at a predetermined angle, and a communication portion 30 is provided at that portion, the communication portion 30 having the same inclination as the upper through hole 22 of the guide bush 20, and the communication portion 30 allows the communication of the manifold 26. The hole 28 and the through hole 23 of the hot nozzle 14 are linearly communicated with each other, so that the flow resistance of the communicating portion between the supply paths 23 and 28 is prevented from increasing. A heater 32 is provided around the manifold 26, and the heater 32 heats a molding material flowing through the through hole 28 of the manifold 26.
[0024]
The sprue 33 has a substantially columnar shape provided so that a predetermined gap is formed between the sprue 33 and the inner surface thereof in the space 12 of the fourth template 11, and the lower end thereof is formed on the upper surface of the manifold 26. It is adapted to be loosely fitted in the provided circular concave portion 31.
[0025]
The sprue 33 includes a sprue main body 34 having a circular concave portion 35 provided on the lower surface side, and a disk-shaped attachment 38 fitted into the concave portion 35 of the sprue main body 34.
[0026]
In the center of the sprue main body 34, a through hole 36 penetrating in the vertical direction (vertical direction) is provided. The through hole 36 is formed in a tapered shape in which the diameter gradually increases from the upper end to the lower end, and the upper end opening is formed in a concave portion 37 having a predetermined curvature. The lower end of an injection nozzle (not shown) of the injection mechanism located is in contact with the injection mechanism.
[0027]
The attachment 38 has a substantially rectangular shape including an upper communication portion 39 which faces in the vertical direction, and a lower communication portion 40 which communicates with a lower end of the upper communication portion 39 and is bent at a predetermined angle with respect to the upper communication portion 39. A communication hole 41 is provided in a state penetrating between the upper and lower surfaces. A lower end of a communication hole 36 of the sprue body 34 communicates with an upper end of the communication hole 41, and an upper end of a communication hole 28 of the manifold 26 communicates with a lower end of the communication hole 41. Are connected.
[0028]
The communication hole 41 of the attachment 38 and the communication hole 36 of the sprue body 34 constitute a communication hole 42 of the sprue 33. In this case, since the lower communication portion 40 of the attachment 38 and the through hole 28 of the manifold 26 are configured to have the same inclination, even if the sprue 33 and the manifold 26 thermally expand, the sprue 33 side The area of the communicating portion between the through hole 42 and the through hole 28 on the side of the manifold 26 does not decrease and the flow resistance does not increase.
[0029]
A heater 43 is provided around the sprue main body 34, and the heater 43 heats the molding material flowing through the through hole 42 of the sprue 33.
[0030]
The through hole 42 of the sprue 33, the through hole 28 of the manifold 26, and the through hole 23 of the hot nozzle 14 configured as described above form a series of molding material passages 44 for supplying molding material from the injection nozzle to the cavity. It is composed.
[0031]
An actuator 46 is provided on a portion of the fourth template 11 located above the hot nozzle 14 in the vertical direction. The actuator 46 has a plunger 47 movably provided in the cylinder chamber 13 provided in the fourth template 11, and the plunger 47 is moved up and down in the cylinder chamber 13. The connected valve 48 opens and closes the injection hole 45 located at the lower end of the molding material passage 44.
[0032]
The valve 48 has a round bar shape whose upper end is connected to the center of the plunger 47, and has a valve insertion hole 27 of the manifold 26, a valve insertion hole 21 of the guide bush 20, and a lower portion of the hot nozzle body 15. The injection hole 45 of the molding material passage 44 is opened and closed at the lower end by inserting the through hole 19.
[0033]
Then, the mold clamping mechanism (not shown) is operated to clamp the fixed mold 3 and the movable mold, and a cavity (not shown) having a predetermined shape is formed between them. When the molding material is supplied to the molding material passage 44 from the injection nozzle while being in contact with the upper end of the molding material 33, the molding material flows through the molding material passage 44 and reaches the injection hole 45 at the lower end of the molding material passage 44.
[0034]
Then, by actuating the actuator 46 to raise the valve 48 to open the injection hole 45, the molding material in the molding material passage 44 is injected into the cavity from the injection hole 45, and a predetermined amount of the molding material is injected into the cavity. Is filled.
[0035]
Then, after the molding material is cured by holding for a predetermined time, the mold 2 is opened, the ejector pins and the like are actuated to release the molded product from the cavity, thereby conforming to the shape of the cavity. A molded article is obtained.
[0036]
In the injection molding apparatus 1 according to this embodiment configured as described above, the through hole 28 of the manifold 26 is formed substantially linearly, and the upper end thereof communicates with the lower end of the through hole 42 of the sprue 33. Since the lower end communicates with the upper end of the through hole 23 of the hot nozzle 14, there is no longer a portion bent at a right angle in the middle of the through hole 28 of the manifold 26. Accordingly, the flow resistance in the through hole 28 of the manifold 26 is partially increased, so that the molding material does not stay in the molding material passage 44, so that a predetermined amount of the molding material can be surely introduced into the cavity. Injection filling can be performed, and a molded product of a certain high quality can be molded.
[0037]
The lower end of the manifold 26 is bent, and a communication portion 30 is provided at that portion, the communication portion 30 having the same inclination as the through hole 23 on the hot nozzle 14 side, and the lower end of the communication portion 30 is connected to the upper end of the through hole 23 of the hot nozzle 14. Can communicate linearly with the through hole 28 on the manifold 26 side and the through hole 23 on the hot nozzle 14 side. Therefore, even when the manifold 26 and the hot nozzle 14 are thermally expanded, the molding material stays in that portion without reducing the area of the communicating portion between the two through holes 23 and 28 and increasing the flow resistance. A predetermined amount of molding material can be supplied into the cavity without the need to do so.
[0038]
Furthermore, by providing an attachment 38 having a communication hole 41 at the lower end of the sprue main body 34, the communication hole 41 having the same inclination as the through hole 28 on the manifold 26 side, the through hole 42 on the sprue 33 side and the through hole 28 on the manifold 26 side are provided. Can be communicated linearly. Therefore, even when the sprue 33 and the manifold 26 thermally expand, the area of the communicating portion between the two through holes 28 and 42 does not decrease and the flow resistance does not increase, and the molding material stays in that portion. As a result, a predetermined amount of molding material can be supplied into the cavity.
[0039]
By providing the attachment 38 having the communication hole 41 at the lower end of the sprue 33, the communication part 30 bent at the lower end of the through hole 28 of the manifold 26 can be provided by machining.
[0040]
In the above description, the lower end of the manifold 26 is bent to provide the communication portion 30 at that portion. However, the upper end of the manifold 26 is bent to provide a communication portion at that portion, and the lower end of the manifold 26 is provided. The portion may be provided with an attachment having a communication hole.
[0041]
【The invention's effect】
As described above, according to the injection molding apparatus of the present invention, since the through hole of the manifold is formed in a substantially straight line, there is no portion bent at a right angle in the middle of the through hole of the manifold. Therefore, since the flow resistance in the through hole of the manifold partially increases and the molding material does not stay in the middle of the through hole, it is necessary to reliably inject and fill a predetermined amount of the molding material into the cavity. Thus, it is possible to form a molded product of a certain high quality.
[0042]
In addition, the through hole of the manifold is inclined at a gentle angle, and the lower end portion of the through hole is bent to provide a communication portion having an inclination corresponding to the upper end portion of the through hole of the hot nozzle. The hole and the through hole of the hot nozzle can be communicated linearly. Therefore, even when the manifold and the hot nozzle thermally expand, the area of the communicating portion between the two through holes does not decrease and the flow resistance does not increase, and a predetermined amount of the molding material is securely inserted into the cavity. Can be supplied.
[0043]
Further, by providing an attachment having a communication hole whose inclination coincides with the through hole of the manifold at the lower end of the sprue, the through hole of the manifold and the through hole of the sprue can be communicated linearly. Therefore, even when the sprue and the manifold are thermally expanded, the area of the communicating portion between the two through holes does not decrease and the flow resistance does not increase, and the predetermined amount of the molding material is reliably supplied into the cavity. Will be able to do that.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing an embodiment of an injection molding apparatus according to the present invention.
FIG. 2 is a partially enlarged view of FIG.
FIG. 3 is a sectional view showing a schematic configuration of a conventional injection molding apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Injection molding apparatus 2 Molding die 3 Fixed die 14 Hot nozzle 19 Lower through hole 22 Upper through hole 26 Manifold 28, 36 Through hole 30 Communication part 33 Sprue 38 Attachment 39 Upper communication part 40 Lower communication part 41 Communication hole 44 Molding Material passage

Claims (3)

A mold having a fixed mold and a movable mold which are relatively openably provided to form a mold, forming a cavity between the two molds when the molds are clamped, and a mold provided in the fixed mold. A hot nozzle having a through-hole communicating with the cavity, and a through-hole provided at a fixed die portion obliquely above the hot nozzle and communicating with an injection nozzle located above the fixed die. A sprue, a manifold provided in a fixed mold portion between the hot nozzle and the sprue, and a manifold having a through hole communicating the through hole of the hot nozzle and the through hole of the sprue; In an injection molding apparatus for forming a series of molding material passages from the injection nozzle to the cavity by a through hole of a nozzle, a through hole of the manifold, and a through hole of the sprue, Injection molding apparatus characterized by the formation of the through hole of the in manifold substantially linearly. The injection molding apparatus according to claim 1,
The through hole of the manifold is inclined at a gentle angle, and the lower end of the through hole is bent to provide a communication portion at the same portion as the upper end of the through hole of the hot nozzle. Injection molding equipment. The injection molding apparatus according to claim 1 or 2,
Attachment having, at a lower end portion of the sprue, a communication hole formed of an upper communication portion that is inclined with the through hole of the sprue, and a lower communication portion that is communicated with the communication portion and that is inclined with the through hole of the manifold. An injection molding apparatus comprising:

Images