CN112203825A

CN112203825A - Pins, sleeves, or inserts

Info

Publication number: CN112203825A
Application number: CN201980035797.XA
Authority: CN
Inventors: 玉谷智
Original assignee: Yugu Manufacturing Co ltd
Current assignee: Yugu Manufacturing Co ltd
Priority date: 2018-05-31
Filing date: 2019-05-30
Publication date: 2021-01-08
Also published as: WO2019230870A1; JP2019209532A; JP6436260B1

Abstract

The invention provides a pin, a sleeve or an insert, which can reliably discharge gas even if the pin is small in diameter, and can ensure necessary strength. The pin (1), the sleeve or the insert has a main body part and a flange part arranged at the rear end of the main body part, a plurality of grooves (1a) are formed in the longitudinal direction of the outer peripheral surface of the main body part, and narrow parts (20a) with narrow width in the outer peripheral surface direction and wide parts (21a) with wide width in the outer peripheral surface direction are alternately and continuously formed in the grooves (1 a).

Description

Pins, sleeves, or inserts

Technical Field

The present invention relates to a pin, a sleeve, or an insert that is fitted into an insert molding die, and relates to a pin, a sleeve, or an insert in which an exhaust groove is formed.

Background

Conventionally, there have been known a push-out pin having a gas discharge groove formed in a tip end and an outer peripheral surface thereof, a push-out pin having a structure in which a plurality of gas escape grooves are formed inside a cylinder combined with a plurality of gas discharge members, and the like, in order to discharge gas in a cavity of a molding die to the outside (non-patent document 1 and patent documents 1 to 4).

Non-patent document 1: missimi, incorporated by reference, parts catalogues 2015.4, P93 for plastic molds, gas-venting straight ejector pins

Patent document 1: japanese laid-open patent publication No. 2002-1776

Patent document 2: japanese patent No. 3587845

Patent document 3: japanese patent No. 4678616

Patent document 4: japanese patent laid-open publication No. 2011-

However, the ejector pin and the like described in non-patent document 1 and

patent document

1 or 2 have a problem in that it is difficult to effectively transmit the pressure at the time of gas ejection, and the gas discharge effect is poor.

Further, the ejector pins described in

patent documents

3 and 4 are difficult to confirm the clogging of the plurality of gas escape grooves formed inside the column, and a dedicated resin clogging removing device is required for the clogging, and it is difficult to form the gas escape grooves in the ejector pins having a small diameter.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object thereof is to provide a pin, a sleeve, or an insert that can reliably discharge gas even with a small-diameter pin or the like and can secure necessary strength.

The pin, the sleeve, or the insert of the invention of mode 1 is fitted into and inserted into a molding die for forming a cavity filled with a molten material, wherein the pin, the sleeve, or the insert has only a main body portion, or has the main body portion and a flange portion provided at a rear end of the main body portion, and a plurality of grooves are formed in a longitudinal direction of an outer peripheral surface of the main body portion, and the grooves are alternately and continuously formed with shallow groove portions having a shallow depth with respect to the outer peripheral surface and deep groove portions having a deep depth with respect to the outer peripheral surface.

In the pin, the sleeve, or the insert of the aspect 1, since the plurality of grooves are formed in the longitudinal direction of the outer peripheral surface of the main body portion, even when one groove is blocked by accumulation of gas such as resin, gas can be reliably discharged from the other groove. Further, since the shallow groove portions and the deep groove portions are alternately and continuously formed, even a pin or the like having a small diameter can secure a necessary strength, and the venturi effect that can increase the flow velocity with a decrease in pressure is utilized by contracting the fluid flow, so that gas accumulation is less likely to occur, and therefore, the groove can be prevented from being clogged. The longitudinal direction of the outer peripheral surface on which the plurality of grooves are formed is a direction away from the cavity from a tip portion adjacent to or close to the cavity.

The pin, the sleeve, or the insert of the invention of mode 2 is fitted and inserted into a molding die for forming a cavity filled with a molten material, wherein the pin, the sleeve, or the insert has only a main body portion, or has the main body portion and a flange portion provided at a rear end of the main body portion, and a plurality of grooves are formed in a longitudinal direction of an outer peripheral surface of the main body portion, and a narrow width portion having a narrow width in the outer peripheral surface direction and a wide width portion having a wide width in the outer peripheral surface direction are alternately and continuously formed in the grooves.

In the pin, the sleeve, or the insert of the aspect 2, since the plurality of grooves are formed in the longitudinal direction of the outer peripheral surface of the main body portion, even when one groove is blocked by accumulation of gas such as resin, gas can be reliably discharged from the other groove. Further, since the narrow width portions and the wide width portions are alternately and continuously formed, even a pin or the like having a small diameter can secure a necessary strength, and the venturi effect that can increase the flow velocity with a decrease in pressure is utilized by contracting the fluid flow, so that the gas accumulation is less likely to occur, and the groove can be prevented from being clogged. The longitudinal direction of the outer peripheral surface on which the plurality of grooves are formed is a direction away from the cavity from a tip portion adjacent to or close to the cavity.

The invention of mode 3 is the pin, the sleeve, or the insert of

mode

1 or 2, wherein the groove is formed by a curved surface. Therefore, in the grooves formed by the curved surface, the shallow groove portions and the deep groove portions are alternately formed repeatedly, or the narrow width portions and the wide width portions are alternately formed repeatedly, so that the resistance of the fluid is reduced as compared with the grooves not formed by the curved surface, the venturi effect can be improved, and the gas accumulation is less likely to occur, so that the clogging of the grooves can be prevented.

The invention of embodiment 4 is the pin, the sleeve, or the insert according to any one of embodiments 1 to 3, wherein the plurality of grooves are formed such that positions of all of the deep groove portions or the wide width portions do not overlap in the longitudinal direction. Therefore, even a pin with a small diameter or the like can be ensured with a necessary thickness, and a necessary strength can be reliably ensured.

The invention of mode 5 is the pin, the sleeve, or the insert according to any one of modes 1 to 4, wherein adjacent grooves of the plurality of grooves communicate with each other at a predetermined portion. Therefore, even when the groove is clogged at a plurality of positions, a gas escape passage can be ensured, and therefore, gas discharge can be performed more reliably.

The invention according to mode 6 is the pin, the sleeve, or the insert according to any one of modes 1 to 5, wherein the flange portion has a groove. Therefore, gas can be discharged from the groove formed in the flange portion.

The invention of embodiment 7 is the pin, the sleeve, or the insert of embodiment 6, wherein the groove formed in the flange portion is a plurality of grooves formed in both the upper surface and the outer peripheral surface of the flange portion. Therefore, the gas reaching the vicinity of the upper surface of the flange portion can be discharged rearward of the flange portion via the groove formed in the upper surface of the flange portion and the groove formed in the outer peripheral surface of the flange portion.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the invention of the

mode

1 or 2, even when one groove is blocked by accumulation of gas such as resin, gas can be reliably discharged from the other groove, and necessary strength can be secured even for a pin or the like having a small diameter. Further, since gas accumulation is less likely to occur due to the venturi effect, clogging of the groove can be prevented. Further, according to the invention of mode 3, clogging of the groove can be further prevented by enhancing the venturi effect. Further, according to the invention of the aspect 4, the necessary thickness of the pin can be ensured even for the pin having a small diameter or the like, and therefore the necessary strength can be reliably ensured.

According to the invention of the mode 5, since the escape passage of the gas can be secured even when the clogging portion of the groove is generated in a plurality of places, the gas discharge can be performed more reliably. Further, according to the invention of the mode 6, it is also possible to discharge gas from the groove formed in the flange portion. Further, according to the invention of the mode 7, the gas reaching the vicinity of the upper surface of the flange portion can be discharged rearward of the flange portion via the groove formed in the upper surface of the flange portion and the groove formed in the outer peripheral surface of the flange portion.

Drawings

Fig. 1 is a sectional view of a molding die into which a pin, a sleeve, or an insert of the present invention is fitted and inserted.

Fig. 2 is a perspective view of the pin of the present invention.

Fig. 3 is a sectional view showing a state where the pin of the present invention is fitted and inserted into the mold.

Fig. 4 (a) to (d) are sectional views of the pin of the present invention.

Fig. 5 (a) is an enlarged front view of the pin of the present invention, and fig. 5 (b) is a sectional view taken along line a-a of fig. 5 (a).

Fig. 6 is a front view of the pin of the first embodiment of the present invention.

Fig. 7 is a view of the pin of the first embodiment of fig. 6 rotated by 45 degrees.

Fig. 8 is a front view of a pin according to a second embodiment of the present invention.

Fig. 9 is a view of the pin of the second embodiment of fig. 8 rotated by 45 degrees.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings. In addition, the present invention is not limited to the following embodiments.

Fig. 1 is a sectional view of a resin molding die for injection molding into which a pin, a sleeve, or an insert of the present invention is fitted. The relationship of the pin, sleeve or insert of the present invention to the mold is illustrated using this figure. The mold is configured to be opened and closed by moving the movable mold 14 relative to the fixed mold 13, and is closed when the molten resin as the molding material is filled therein, and opened when the molded product is taken out.

When the mold is opened and closed, the ejector pin 1, the product pin 3, and the gate lock pin 6 are slidably inserted through respective pin holes formed in the movable mold 14. On the other hand, the knockout sleeve 2, the core pin 4, and the insert 5 (also referred to as a core) are not slidably fixed but fixed to the respective pin holes. The molten resin is injected from the resin injection port 10 into the product portion 9 (also referred to as a cavity) through the gate 11.

Here, although not shown in fig. 1, the pin of the present invention includes, in addition to the ejector pin 1, the product pin 3, the gate lock pin 6, and the core pin 4, all pins such as an injection pin and a valve gate pin, which are inserted into the mold in a fitting manner while being adjacent to a rail through which the molten molding material passes, including the product portion 9 and/or the gate 11 of the mold.

The sleeve of the present invention includes, in addition to the ejector sleeve 2 shown in fig. 1, all sleeves that are adjacent to a rail through which a molten molding material passes, including the product portion 9 and/or the gate 11 of the mold, and that are fitted and inserted into the mold. In fig. 1, for the sake of easy understanding, the clearance between the pin and the die is exaggerated, and is actually only a slight clearance of a slidable degree.

Similarly, the insert of the present invention includes, in addition to the insert 5 shown in fig. 1, all inserts that are adjacent to a rail through which a molten molding material passes, including the product portion 9 and/or the gate 11 of the mold, and that are fitted and inserted into the mold.

Fig. 2 is a perspective view of a pin according to a first embodiment of the present invention. Fig. 3 is a sectional view of the first embodiment of the present invention in a state where the pin is fitted and inserted into the mold. Fig. 4 (a) to (d) are cross-sectional views of the pin according to the first embodiment of the present invention. Fig. 5 (a) is an enlarged front view of the pin according to the first embodiment, and fig. 5 (b) is a sectional view taken along line a-a of fig. 5 (a). Fig. 6 is a front view of the pin according to the first embodiment, and fig. 7 is a front view of the pin of fig. 6 rotated by 45 degrees. The pin of the first embodiment will be specifically described with reference to these drawings.

The pin (ejector pin) 1 of the first embodiment includes a cylindrical body portion 15a and a flange portion 15b provided at the rear end of the body portion 15 a. Four

grooves

1a, 1b, 1c, and 1d are formed in the longitudinal direction of the outer periphery of the body 15a at positions that divide the outer periphery into four equal parts. The number of grooves formed in the pin, the sleeve, or the insert of the present invention is not limited to the four grooves shown in the pin 1 of the first embodiment, and may be two or more. By forming the plurality of grooves, even when one groove is blocked by accumulation of gas such as resin, gas can be reliably discharged from the other grooves. The four

grooves

1a, 1b, 1c, and 1d formed in the pin 1 have terminal ends located in the middle of the body 15 a. This is because, as shown in fig. 1, the entire outer periphery of the main body portion 15a of the pin 1 does not come into sliding contact with the die, but as in the core pin 4 shown in fig. 1, when the entire outer periphery of the main body portion comes into sliding contact with the die, the terminal ends of the plurality of grooves may be extended to reach the flange portion, and such a configuration is included in the present invention.

In the pin of the first embodiment, as shown in the sectional view of fig. 4 and the enlarged front view of the pin of fig. 5, shallow groove portions 20 having the smallest depth with respect to the outer peripheral surface and deep groove portions 21 having the largest depth with respect to the outer peripheral surface are alternately and continuously formed in four

grooves

1a, 1b, 1c, and 1 d. That is, the groove depth gradually decreases from the deep groove portion 21 to the shallow groove portion 20, and the groove depth gradually increases from the shallow groove portion 20 to the deep groove portion 21. This can cause the gas flow drawn from the pin tip into the deep groove portion 21 to be contracted at the shallow groove portion 20, and the fluid flow to be contracted, thereby making it possible to utilize the venturi effect in which the flow velocity increases with a decrease in pressure, and thus to prevent the occurrence of gas accumulation, so that the groove can be prevented from being clogged. In the vicinity of the deep termination groove portions 22, the groove depth may gradually increase from the shallow groove portions 20 in the front to the deep termination groove portions 22, but the present invention is not limited thereto. This is because the pin 1 does not come into sliding contact with the mold of the main body portion in the vicinity of the terminal deep groove portion 22, and therefore the venturi effect described above cannot be expected.

The deep groove portions 21 of the four

grooves

1a, 1b, 1c, and 1d are formed so as not to overlap in the longitudinal direction. Thus, even a pin having a small diameter or the like can be ensured with a required thickness, and thus required strength can be reliably ensured. Here, the strength required for the ejector pin is strength required for a function of ejecting a product by sliding when the mold is opened and closed. In addition, the strength necessary for the function that should be performed by other pins, sleeves, or inserts is also referred to. Note that, in fig. 3, arrows indicate gas flows, and for the sake of understanding, the gap between the pin and the mold is exaggerated and actually is only a minute gap of a slidable degree.

As described above, the pin 1 of the first embodiment alternately and continuously forms the shallow groove portions 20 having a shallow depth with respect to the outer peripheral surface and the deep groove portions 21 having a deep depth with respect to the outer peripheral surface, and as shown in fig. 5 (a), the wide portions 21a having the widest width in the outer peripheral surface direction are formed at positions corresponding to the deep groove portions 21, and the narrow portions 20a having the narrowest width in the outer peripheral surface direction are formed at positions corresponding to the shallow groove portions 20. Therefore, the narrow width portions 20a and the wide width portions 21a of the pin 1 of the first embodiment are alternately and continuously formed. That is, the width in the outer peripheral surface direction gradually decreases from the wide portion 21a to the narrow portion 20a, and the width in the outer peripheral surface direction gradually increases from the narrow portion 20a to the wide portion 21 a. This makes it possible to cause the air flow drawn from the pin tip into the wide portion 21a to be constricted at the narrow portion 20a, and to cause the fluid flow to be constricted, thereby making it difficult to generate gas accumulation by the venturi effect that increases the flow velocity with a decrease in pressure, and therefore, it is possible to prevent the groove from being clogged. In the vicinity of the terminal wide portion 22a, the width in the outer peripheral surface direction may gradually increase from the front narrow portion 20a to the terminal wide portion 22a, but the present invention is not limited thereto. This is because the pin 1 does not come into sliding contact with the mold of the main body portion in the vicinity of the terminal wide portion 22a, and the venturi effect described above cannot be expected. In fig. 5, the shallow groove portions 20 and the deep groove portions 21 are indicated by dots, and the corresponding narrow width portions 20a and the corresponding wide width portions 21a are indicated by straight lines, but the shallow groove portions 20 (narrow width portions 20a) and the deep groove portions 21 (wide width portions 21a) are preferably not formed with sharp corners but are located at the tops of rounded corner surfaces having rounded corners. The shallow groove portions 20 (narrow width portions 20a) and the deep groove portions 21 (wide width portions 21a) may have widths in the longitudinal direction of the groove.

Further, since the four

grooves

1a, 1b, 1c, and 1d are formed by curved surfaces, the resistance of the fluid is reduced as compared with a groove that is not formed by a curved surface, and the venturi effect can be improved. Further, the

wide portions

21a and 22a are formed at positions corresponding to the

deep groove portions

21 and 22, and the narrow portion 20a is formed at a position corresponding to the shallow groove portion 20, whereby the venturi effect can be increased. The above-described configuration is also included in the present invention because the venturi effect can be exhibited even in the case where the deep groove portions 21 and the shallow groove portions 20 are alternately continuous and the groove width is constant, and in the case where the wide portions 21a and the narrow portions 20a are alternately continuous and the groove depth is constant.

As shown in fig. 7, the wide portions 21a (deep groove portions) of the four

grooves

1a, 1b, 1c, 1d are formed so as not to overlap in the longitudinal direction. Thus, even a pin having a small diameter or the like can be ensured with a required thickness, and thus required strength can be reliably ensured. Here, the present invention can be applied to a pin having a minimum diameter of up to 0.2mm according to a conventional machining technique. In the case where the minimum diameter of the pin is 0.2mm, the width of the narrow width portion is 0.087178mm, the width of the wide width portion is 0.173205mm, the depth of the shallow groove portion is 0.01mm, and the depth of the deep groove portion is 0.05 mm. The width and depth of the groove can be precisely measured using a three-dimensional measuring instrument, and an example thereof is a multisensor measuring instrument (O-instect 543, manufactured by CARL ZEISS).

In the flange portion 15b of the pin 1 of the first embodiment,

grooves

1e and 1f are formed on both the upper surface and the outer peripheral surface of the flange portion 15 b. The

grooves

1e and 1f allow the gas reaching the vicinity of the upper surface of the flange portion 15b to be discharged rearward of the flange portion 15b via the groove 1e formed in the upper surface of the flange portion 15b and the groove 1f formed in the outer peripheral surface of the flange portion 15 b. When the outer peripheral surface of the flange portion 15b is in sliding contact with the mold, the groove 1f may be formed by alternately and continuously forming shallow groove portions having the smallest depth with respect to the outer peripheral surface and deep groove portions having the largest depth with respect to the outer peripheral surface, or by alternately and continuously forming narrow width portions having the smallest width in the outer peripheral surface direction and wide width portions having the largest width in the outer peripheral surface direction, in the same manner as the main body portion 15 a. This makes it difficult to generate gas accumulation by the venturi effect that increases the flow velocity with a decrease in pressure, and therefore, clogging of the groove 1f can be prevented.

In addition, the pin 1 of the first embodiment has a circular cross section, but the present invention is not limited thereto. For example, the present invention can be applied to a pin, a sleeve, or an insert having a polygonal shape with a triangular, quadrangular, pentagonal, hexagonal, or more cross-section, and a special shape such as an oval, star, heart, or the like.

In the first embodiment, the resin molding die for injection molding is described, but the present invention is not limited thereto. For example, the present invention can be applied to a mold used in a molding machine (a molding machine such as injection molding, compression molding, injection molding, or extrusion molding) for filling resin, rubber, and metal such as aluminum or magnesium and a pin, a sleeve, or an insert provided in a mold used in a casting machine such as die casting.

Fig. 8 is a front view of a pin according to the second embodiment, and fig. 9 is a front view of the pin of fig. 8 rotated by 45 degrees. The pin of the second embodiment is explained using these diagrams.

Adjacent grooves

30a, 30b of the plurality of grooves of the pin 30 of the second embodiment communicate at a predetermined location 32. This ensures a gas escape passage even when a large number of closed portions of the groove are formed, and therefore, gas discharge can be performed more reliably. The wide portions 31 (deep groove portions) are formed so as not to overlap in the longitudinal direction. Thus, even a pin having a small diameter or the like can be ensured to have a necessary pin thickness. The other structures are the same as those of the pin 1 of the first embodiment, and therefore, the description thereof is omitted.

Industrial applicability

The pin, the sleeve, or the insert of the present invention is used by being fitted into a molding die.

Description of the reference numerals

1. 30 pin

1a, 1b, 1c, 1d, 1e, 1f, 30a, 30b slots

15a main body part

15b flange part

20 shallow groove part

20a narrow part

21 deep groove part

21a, 31 wide part

22 terminal deep groove portion

22a terminal wide part

32 predetermined location.

Claims

1. A pin, sleeve or insert to be fitted into a molding die for forming a cavity to be filled with a molten material, the pin, sleeve or insert being characterized in that,

the pin, the sleeve, or the insert has only a main body portion, or has the main body portion and a flange portion provided at a rear end of the main body portion, and a plurality of grooves are formed in a longitudinal direction of an outer peripheral surface of the main body portion,

the groove is formed by alternately and continuously forming a shallow groove portion having a shallow depth with respect to the outer peripheral surface and a deep groove portion having a deep depth with respect to the outer peripheral surface.

2. A pin, sleeve or insert to be fitted into a molding die for forming a cavity to be filled with a molten material, the pin, sleeve or insert being characterized in that,

the groove is formed with narrow portions having a narrow width in the outer peripheral surface direction and wide portions having a wide width in the outer peripheral surface direction alternately and continuously.

3. A pin, sleeve or insert as claimed in claim 1 or claim 2, wherein the slot is formed by a curved surface.

4. The pin, sleeve or insert of any one of claims 1 to 3, wherein the plurality of grooves are formed such that positions of all of the deep groove portions or the wide width portions do not overlap in a longitudinal direction.

5. A pin, sleeve or insert according to any one of claims 1 to 4, wherein adjacent slots of the plurality of slots communicate at predetermined locations.

6. A pin, sleeve or insert according to any one of claims 1 to 5, wherein the flange portion is formed with a groove.

7. The pin, sleeve or insert of claim 6, wherein the grooves formed in the flange portion are a plurality of grooves formed in both the upper surface and the outer peripheral surface of the flange portion.