CN216442931U

CN216442931U - Internal expansion pull pin mechanism and molding mechanism

Info

Publication number: CN216442931U
Application number: CN202122158853.6U
Authority: CN
Inventors: 刘光; 钱正军; 蒋绪强; 吴雅迪
Original assignee: Tsp Shanghai Precision Tooling Co ltd
Current assignee: Tsp Shanghai Precision Tooling Co ltd
Priority date: 2021-09-07
Filing date: 2021-09-07
Publication date: 2022-05-06
Anticipated expiration: 2031-09-07

Abstract

The embodiment of the utility model provides an internal expansion pull pin mechanism and a molding mechanism, belonging to the field of insert injection. The internal expansion pull pin mechanism and the molding mechanism comprise: the top end of the expansion sleeve is used for penetrating into the inner part of the insert of the molding mechanism; the expansion inner pin is arranged inside the expansion sleeve, and the diameter of the top end of the expansion inner pin is larger than the inner diameter of the expansion sleeve; a top plate connected with the expansion inner pin; and the push rod is connected with the top plate and is parallel to the length direction of the expansion inner pin. Through the cover half promotion push rod downstream when the compound die action for the round pin moves down in the inflation, thereby makes the outside expansion sleeve of setting round pin in the inflation outwards expand and have the trend of downstream, and then lets the inserters of entangling the expansion sleeve closely laminate with the mould core. The internal expansion pull pin mechanism and the molding mechanism improve the problems of the flash and poor encapsulation of the surface of the insert under the condition that the appearance of a blind hole insert injection molding piece is not influenced.

Description

Internal expansion pull pin mechanism and molding mechanism

Technical Field

The utility model relates to the field of insert injection molding, in particular to an internal expansion pull pin mechanism and a molding mechanism.

Background

Insert injection molding is a process of fixing an insert at a proper position in an injection mold in advance, then injecting plastic for molding, and after mold opening, tightly wrapping and burying the insert in the plastic by the cooled and solidified plastic to obtain a product with inserts such as threads, electrodes and the like.

When the appearance of the blind hole insert injection molding piece is not allowed to be a through hole, the insert can flow along with molten plastic in the injection molding filling process, so that the fit clearance between the insert and a mold core is caused, and the flash of the insert surface and poor encapsulation are generated.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model aims to provide an internal expansion pull pin mechanism and a molding mechanism, which can fix an insert on a mold core during injection molding of a mold and reduce the flash of the insert surface and poor encapsulation.

In order to achieve the above object, an aspect of the embodiments of the present invention provides an internal expansion pull pin mechanism, including:

the top end of the expansion sleeve is used for penetrating into the inner part of the insert of the molding mechanism;

the expansion inner pin is arranged inside the expansion sleeve, and the diameter of the top end of the expansion inner pin is larger than the inner diameter of the expansion sleeve;

a top plate connected with the expansion inner pin;

and the top plate is used for being installed inside a mold core of the molding mechanism, so that when the push rod is subjected to downward pressure, the top plate can drive the expansion inner pin to move downwards to expand the inner diameter of the top of the expansion sleeve.

Optionally, the molding mechanism includes a first core, a second core and a third core arranged in sequence from top to bottom, the top of the first core is used for mounting the insert, a cavity is arranged between the second core and the third core to accommodate the top plate, and passages for accommodating the expansion sleeve and the expansion inner pin are arranged inside the first core and the second core.

Optionally, the expansion sleeve has a bottom radius greater than a top radius.

Optionally, the bottom of the expansion sleeve is provided with a first spring to jack the expansion sleeve upwards.

Optionally, a second spring is arranged at the bottom of the top plate to jack the top plate upwards.

Optionally, the top plate comprises a key pin disposed at a junction of the expansion inner pin and the top plate to connect the expansion inner pin and the top plate.

In another aspect, embodiments of the present invention provide a molding mechanism comprising a molding mechanism body and an internal expansion pull pin mechanism as described in any one of the above.

Through the technical scheme, the fixed die pushes the push rod to move downwards during the die closing action, so that the expansion inner pin which is parallel to the push rod and is also connected to the top plate moves downwards, the expansion sleeve arranged outside the expansion inner pin expands outwards and has the tendency of moving downwards, and the insert sleeved on the expansion sleeve is tightly attached to the die core. The internal expansion pull pin mechanism and the molding mechanism improve the problems of the flash and poor encapsulation of the surface of the insert under the condition that the appearance of a blind hole insert injection molding piece is not influenced.

Additional features and advantages of embodiments of the utility model will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the embodiments of the utility model and not to limit the embodiments of the utility model. In the drawings:

FIG. 1 is a three-dimensional view of an internal expansion pull pin mechanism according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of an internal expansion pull pin mechanism according to an embodiment of the present invention.

Description of the reference numerals

1. Expansion sleeve 2 and expansion inner pin

3. Top plate 4, push rod

5. A first spring 6 and a second spring

7. Key pin 8, first core

9. Second core 10, third core

11. Insert piece

Detailed Description

The following detailed description of embodiments of the utility model refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the utility model, are given by way of illustration and explanation only, not limitation.

FIG. 1 is a three-dimensional view of an internal expansion pull pin mechanism according to an embodiment of the present invention; fig. 2 is a cross-sectional view of an internal expansion pull pin mechanism according to an embodiment of the present invention. This internal expansion draws pin mechanism includes: expansion sleeve 1, expansion inner pin 2, top plate 3, push rod 4 and insert 11. In this mechanism, the top end of the expansion sleeve 1 is intended to penetrate into the interior of the insert 11 of the molding mechanism. The expansion inner pin 2 is arranged inside the expansion sleeve 1, and the diameter of the top end is larger than the inner diameter of the expansion sleeve 1. The top plate 3 is connected with the expansion inner pin 2. The push rod 4 is connected with the top plate 3 and is parallel to the length direction of the expansion inner pin 2, and the top plate 3 is used for being installed inside a mold core of a molding mechanism so that when the push rod 4 is pressed downwards, the top plate 3 can drive the expansion inner pin 2 to move downwards to expand the inner diameter of the top of the expansion sleeve 1.

In the mechanism, the push rod 4 and the expansion inner pin 2 can be parallel, so that the expansion inner pin 2 can be better driven when the push rod 4 is pushed, and the angle setting between the expansion inner pin 2 and the top plate 3 can be various forms known to those skilled in the art, and can be 30 degrees, 60 degrees, 90 degrees and the like. However, in a preferred example of the present invention, the angle between the inner expansion pin 2 and the top plate 3 may be 90 °, and the 90 between the inner expansion pin 2 and the top plate 3 may facilitate the mold core casting hole and may enable the top plate 3 to better pull the inner expansion pin 2 to move, compared to other angles.

When carrying out the blind hole inserts and moulding plastics, the cover half promotes push rod 4 downstream during the compound die action, it moves down jointly to drive inflation inner pin 2 through roof 3, thereby enlarge the diameter at 1 top of expansion sleeve, make the top of expansion sleeve 1 and inserts 11 combine closely more and grasp inserts 11 and stimulate downwards, let inserts 12 and core closely laminate, prevented that inserts 11 from flowing along with melting at the filling in-process of moulding plastics and causing inserts 11 and the laminating of mould core inserts face overlap and the bad rubber coating condition that the clearance produced appear.

In one embodiment of the present invention, as shown in fig. 2, the molding mechanism includes: a first core 8, a second core 9 and a third core 10. The first core 8, the second core 9 and the third core 10 may be arranged one above the other. The top of the first core 8 is used for mounting an insert 11, and passages capable of accommodating the expansion sleeve 1, the expansion inner pin 2 and the push rod 4 are provided inside the first core 8 and the second core 9, and the insert 11 is placed above the passages accommodating the expansion sleeve 1 and the expansion inner pin 2. A cavity is arranged between the second mold core 9 and the third mold core 10 and can contain the top plate 3, the push rod 4 is applied with downward pressure to drive the expansion inner pin 2 to move downwards, so that the top of the expansion sleeve 1 expands outwards to grasp the insert 11 and pull down, and the insert 12 is tightly attached to the top of the first mold core 8.

In one embodiment of the utility model, as shown in fig. 2, the internal expansion pull pin mechanism comprises a first spring 5 and a second spring 6. The first spring 5 is arranged at the bottom of the expansion sleeve 1, and can push the expansion sleeve 1 out a part upwards so that the top of the expansion sleeve 1 is better provided with the insert 11. In order to allow a better mounting of the first spring 5 at the bottom of the expansion sleeve 1 with a larger contact area with the bottom of the expansion sleeve 1, the radius of the bottom of the expansion sleeve 1 may be larger than the radius of the top. The second spring 6 is provided at the bottom of the top plate 3 and the bottom end of the second spring 6 may contact the cavity of the third core 10, and the third spring may push up the top plate 3 by a certain distance so that the top plate 3 may be displaced downward by a certain distance before the stationary mold pushes the push rod 4 downward.

In one embodiment of the present invention, as shown in fig. 1 and 2, the top plate 3 includes a key pin 7, and the key pin 7 is disposed at a connection point of the expansion inner pin 2 and the top plate 3 to connect the expansion inner pin 2 and the top plate 3 together.

In another aspect, the present invention also provides a molding mechanism comprising a molding mechanism body and an internal expansion draw pin mechanism.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. An internal expansion pull pin mechanism, comprising:

a top plate connected with the expansion inner pin;

2. The internal expansion pull pin mechanism according to claim 1, wherein the molding mechanism comprises a first core, a second core and a third core which are sequentially arranged from top to bottom, the top of the first core is used for installing the insert, a cavity is arranged between the second core and the third core to accommodate the top plate, and the first core and the second core are internally provided with passages for accommodating the expansion sleeve and the expansion internal pin.

3. The internal expansion pull pin mechanism of claim 2, wherein the bottom radius of the expansion sleeve is greater than the top radius.

4. The internal expansion pull pin mechanism of claim 2, wherein the bottom of the expansion sleeve is provided with a first spring to jack the expansion sleeve upward.

5. The internal expansion pull pin mechanism of claim 1, wherein the bottom of the top plate is provided with a second spring to jack the top plate upward.

6. The internal expansion pull pin mechanism of claim 1, wherein the top plate includes a key pin disposed at a junction of the expansion inner pin and the top plate to connect the expansion inner pin and the top plate.

7. A molding mechanism comprising a molding mechanism body and an internally expanding pull pin mechanism as claimed in any one of claims 1 to 6.