CN112721054A

CN112721054A - Internal thread working of plastics mold processing

Info

Publication number: CN112721054A
Application number: CN202011594031.6A
Authority: CN
Inventors: 蔡达伟
Original assignee: Guangzhou Bosen Plastic Products Co ltd
Current assignee: Guangzhou Bosen Plastic Products Co ltd
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2021-04-30

Abstract

The invention provides an internal thread plastic part processing mold, which comprises a front mold and a rear mold; the rear die comprises a die core assembly and a driving device; the mold core assembly comprises a product mold core and a thread mold core driven by the driving device to rotate, the thread mold core is provided with an external thread, the thread mold core is sleeved in the product mold core, and an injection molding mold cavity is formed between the thread mold core and the product mold core; the cooling device is characterized in that the threaded mold core is hollow and contains a cooling shaft core, the threaded mold core can rotate relative to the cooling shaft core, the cooling shaft core is hollow to form a containing cavity, the containing cavity is communicated with a refrigerant pipe, the containing cavity and the refrigerant pipe are internally filled with a cooling medium which flows in a circulating mode, the cooling shaft core is connected with the refrigerant pipe in a sealing mode through a sealing structure, and the technical problem that a long-rod internal thread plastic part is easy to deform during demolding is solved.

Description

Internal thread working of plastics mold processing

Technical Field

The invention relates to the technical field of plastic part processing, in particular to a processing mold for an internal thread plastic part.

Background

A plastic mould is a tool matched with a plastic forming machine in the plastic processing industry to endow plastic products with complete configuration and accurate dimension, and is a tool for producing the plastic products and consists of a plurality of parts, wherein a forming mould cavity is arranged in the tool. During injection molding, the mold is clamped on an injection molding machine, molten plastic is injected into a forming mold cavity and is cooled and shaped in the cavity, then the front mold and the rear mold are separated, a product is ejected out of the mold cavity through an ejection system and leaves the mold, finally the mold is closed again for next injection molding, and the whole injection molding process is carried out in a circulating mode.

The plastic injection molding process mainly comprises four stages of filling, pressure maintaining, cooling and demolding, wherein the four stages directly determine the molding quality of a product, and the four stages are a complete continuous process, and the demolding is the last link in an injection molding cycle. Although the product is cooled and formed, demoulding still has a very important influence on the quality of the product, and improper demoulding mode may cause uneven stress on the product during demoulding and deformation of the product during ejection, for example, when an internal thread workpiece with long thread is machined and demoulded, the thread is easy to deform, resulting in deformation and damage of the product. Therefore, it is important to provide a die capable of preventing deformation of the internal thread workpiece during demolding.

Disclosure of Invention

The invention aims to provide an internal thread plastic part processing mold, which solves the technical problem that an internal thread plastic part of a long rod in the prior art is easy to deform during demolding.

In order to achieve the purpose, the invention provides an internal thread plastic part processing mold, which comprises a front mold and a rear mold; the rear die comprises a die core assembly and a driving device; the mold core assembly comprises a product mold core and a thread mold core driven by the driving device to rotate, the thread mold core is provided with an external thread, the thread mold core is sleeved in the product mold core, and an injection molding mold cavity is formed between the thread mold core and the product mold core; the thread mold core is hollow and contains a cooling shaft core, the thread mold core can rotate relative to the cooling shaft core, the cooling shaft core is hollow to form a containing cavity, the containing cavity is communicated with a refrigerant pipe, the containing cavity and the refrigerant pipe are internally filled with a cooling medium which flows circularly, and the cooling shaft core is hermetically connected with the refrigerant pipe through a sealing structure.

Preferably, the cooling shaft core is a beryllium copper shaft core.

Preferably, the driving means includes a motor, a driving gear, a first driven gear and a second driven gear; when the motor rotates, the driving gear is driven to rotate; the first driven gear is meshed with the driving gear and the second driven gear respectively; and the second driven gear drives the threaded mold core to coaxially rotate.

Preferably, the mold core assemblies at least comprise two groups, and the driving device comprises at least two driving parts which are respectively connected with the threaded mold cores of each group of mold core assemblies and used for driving the threaded mold cores to rotate.

Preferably, the threaded mold core is wrapped by a buffer member, and the buffer member is positioned in a gap between the driven gear and the threaded mold core.

Preferably, the sealing structure comprises a sealing groove and a sealing element arranged on the sealing groove, a groove cavity of the sealing groove is in a circular ring shape, the sealing element is matched with the sealing groove, and the sealing element protrudes from the inside of the sealing groove to seal the cooling shaft core.

Preferably, the seal is a rubber ring.

Preferably, workpiece cooling channels are uniformly embedded in the cavity wall of the product mold core, and the workpiece cooling channels are connected with circulating cooling water.

Preferably, the bottom of the inner cavity of the product mold core is provided with a plurality of bulges in a protruding mode, the bottom of the inner cavity of the product mold core is in a round cake shape, and the part, containing the threaded mold core, of the inner cavity of the product mold core is in a columnar shape.

Compared with the prior art, the invention has the following beneficial effects: the driving device is arranged to drive the threaded mold core to rotate, when the injection in the mold cavity is finished, the front mold and the rear mold are separated, the driving device drives the threaded mold core to rotate, and the product is separated from the threaded mold core by using the external thread on the threaded mold core, so that the product rotates along the internal thread of the product during demolding, demolding is not needed in an ejection mode, and the internal thread of the product is not easy to deform; the cooling channel and the cooling shaft core are arranged simultaneously, the cooling medium which is full of circulating flow is filled in the cooling medium pipe through the accommodating cavity of the cooling shaft core, the product is cooled, the demoulding of the product is not easy to deform during cooling, the cooling of the product is more rapid and stable, the internal thread during demoulding of the product is not easy to deform due to high temperature, and the technical problem that the internal thread plastic part of the long rod is easy to deform during demoulding is solved.

Drawings

FIG. 1 is a schematic view of the overall structure of the mold for processing an internally threaded plastic part according to the present invention;

FIG. 2 is a schematic view of the present invention illustrating the internal structure of a mold for forming internally threaded plastic parts;

fig. 3 is a schematic structural diagram for illustrating the threaded mold core of the present invention.

Reference numerals:

1. a front mold; 2. a rear mold; 21. cooling the shaft core; 212. a rubber ring; 22a, a third driven gear; 22b, a second driven gear; 23. a threaded mold core; 231. an external thread; 24. a water inlet; 25. a water outlet; 26. sealing the water cover plate; 27. cooling the branch pipe; 28. a refrigerant pipe; 29. a buffer member; 210. a bearing; 3. a drive device; 31. a driving gear; 32. a hydraulic motor; 33. a first driven gear; 4. and (5) producing the product.

Detailed Description

The embodiments described below are only a part of the embodiments of the present invention, and not all of them. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Hereinafter, an embodiment of a mold for processing a plastic part with internal threads according to the present invention will be described with reference to fig. 1 to 3.

An internal thread plastic part processing mold comprises a front mold 1 and a rear mold 2; the rear die 2 comprises a die core component and a driving device 3; the mold core assembly comprises a product mold core (not shown in the figure) and a thread mold core 23 which is driven by the driving device 3 to rotate, the thread mold core 23 is provided with external threads 231, the thread mold core 23 is sleeved in the product mold core, and an injection molding mold cavity is formed between the thread mold core 23 and the product mold core; the threaded mold core 23 is hollow and contains a cooling shaft core 21, the threaded mold core 23 can rotate relative to the cooling shaft core 21, the cooling shaft core 21 is hollow to form a containing cavity, the containing cavity is communicated with a refrigerant pipe 28, the containing cavity and the refrigerant pipe 28 are filled with cooling media which circularly flow, and the cooling shaft core 21 is hermetically connected with the refrigerant pipe 28 through a sealing structure.

Specifically, the mold core assemblies at least comprise two groups, and the driving device 3 comprises at least two driving parts which are respectively connected with the threaded mold cores 23 of each group of mold core assemblies and used for driving the threaded mold cores 23 to rotate.

Specifically, the driving device 3 includes a hydraulic motor 32, a driving gear 31, a first driven gear 33, and a second driven gear 22 b; when the hydraulic motor 32 rotates, the driving gear 31 is driven to rotate; the first driven gear 33 is meshed with the driving gear 31 and the second driven gear 22b respectively; the second driven gear 22b drives the threaded mold core 23 to rotate coaxially. The driving member includes a second driven gear 22b and a screw core 23 that rotates together with the second driven gear 22 b.

When the mold core assemblies are two groups, the driving device 3 further comprises a third driven gear 22a and a threaded mold core 23 which coaxially rotates with the third driven gear 22a, and the third driven gear 22a is meshed with the first driven gear 33 and is used for driving the third driven gear 22a to rotate.

Specifically, the cooling shaft core 21 is a beryllium copper shaft core.

The cooling shaft core 21 is a beryllium copper shaft core, which has the effects of improving the heat dissipation efficiency, having good sealing performance and being difficult to leak water.

Specifically, the diameter of the part of the threaded mold core 23 close to the driving device 3 is larger than that of the part of the threaded mold core 23 provided with threads, the part of the threaded mold core 23 with larger diameter is wrapped with a buffer 29, and the buffer 29 is located in a gap between the driven gear and the threaded mold core 23 and used for buffering friction between the driven gear and the threaded mold core 23, so that the driven gear and the threaded mold core 23 are prevented from rotating relative to each other, and meanwhile, direct friction between the threaded mold core 23 and the driven gear can be prevented.

It should be noted that at least two bearings 210 are rotatably connected to the portion of the screw core 23 close to the driven gear, and the inner ring of the bearing 210 is rotatably connected to the cooling shaft core 21.

Specifically, seal structure includes sealed recess and sets up the sealing member on sealed recess, the vallecular cavity of sealed recess is the ring form and sets up on the axle wall of the tip of cooling axle core 21, sealing member and sealed recess looks adaptation, the sealing member is protruding in order to seal cooling axle core 21 in the sealed recess, a coolant for preventing in cooling axle core 21 inside cavity and the coolant pipe 28 overflows and influence and mould plastics, specifically, the sealing member is rubber circle 212, in this embodiment, the circulated cooling water that lets in the coolant pipe 28, adopt hydrologic cycle's mode cooling, thereby make plastics cooling non-deformable.

Specifically, a workpiece cooling channel is uniformly embedded in the cavity wall of the product mold core, the workpiece cooling channel is connected with circulating cooling water, a sealing water cover and a plurality of cooling branch pipes 27 communicated with the sealing water cover are accommodated in the workpiece cooling channel, a sealing water cover plate 26 is in a similar ring shape and is provided with a notch, a water inlet 24 and a water outlet 25 are respectively arranged at two ends of the notch formed by the sealing water cover plate 26, and water flow circulation heat dissipation is performed through the water inlet 24 and the water outlet 25, so that the heat dissipation and cooling effects on the plastic pieces in the injection mold cavity are achieved; in this embodiment, the extension direction of the cooling branch pipes 27 is the same as the demolding direction of the plastic part, and the cooling branch pipes 27 are uniformly distributed around the periphery of the injection mold cavity at intervals.

Specifically, the bottom of the inner cavity of the product mold core is provided with a plurality of bulges in a protruding manner, the bottom of the inner cavity of the product mold core is in a round cake shape, and the part of the inner cavity of the product mold core, which contains the threaded mold core 23, is in a column shape.

In the embodiment, as the driving device 3 is arranged to drive the threaded mold core 23 to rotate, when the injection in the mold cavity is finished, the front mold 1 and the rear mold 2 are separated, the driving device 3 drives the threaded mold core 23 to rotate, and the product 4 is separated from the threaded mold core 23 by using the external thread 231 on the threaded mold core 23, so that the product 4 rotates along the internal thread of the product 4 during the demolding, the demolding is not required to be performed in an ejection mode, and the internal thread of the product 4 is not easy to deform; the cooling channel is arranged at the same time, the cooling shaft core 21 is cooled, cooling media which flows in a circulating mode are filled in the accommodating cavity and the refrigerant pipe 28 of the cooling shaft core 21, the product 4 is cooled, demoulding is not easy to deform during cooling of the product 4, cooling of the product 4 is quicker and more stable, internal threads during demoulding of the product 4 are not easy to deform easily due to high temperature, and the technical problem that plastic parts deform easily during demoulding of internal thread teeth of the long rod is solved.

The driven gears in the present embodiment refer to the second driven gear 22b and the third driven gear.

The working conditions of the embodiment are as follows: when the injection molding is carried out in the mold cavity, and the cooling operation is carried out, the front mold 1 and the rear mold 2 are separated, the front mold 1 is left on the injection molding machine, and then the hydraulic motor 32 is driven to rotate, so that the driving gear 31 is driven to rotate, the second driven gear 22b and the third driven gear 22a are further driven to rotate through the first driven gear 33, the threaded mold core 23 is driven to rotate, the product 4 falls off from the threaded mold core 23, and the demolding operation is realized.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention.

Claims

1. An internal thread plastic part processing mold is characterized by comprising a front mold and a rear mold;

the rear die comprises a die core assembly and a driving device;

the mold core assembly comprises a product mold core and a thread mold core driven by the driving device to rotate, the thread mold core is provided with an external thread, the thread mold core is sleeved in the product mold core, and an injection molding mold cavity is formed between the thread mold core and the product mold core;

the thread mold core is hollow and contains a cooling shaft core, the thread mold core can rotate relative to the cooling shaft core, the cooling shaft core is hollow to form a containing cavity, the containing cavity is communicated with a refrigerant pipe, the containing cavity and the refrigerant pipe are internally filled with a cooling medium which flows circularly, and the cooling shaft core is hermetically connected with the refrigerant pipe through a sealing structure.

2. The mold of claim 1 wherein the cooling mandrel is a beryllium copper mandrel.

3. The mold of claim 1 wherein the drive means comprises a motor, a drive gear, a first driven gear and a second driven gear;

when the motor rotates, the driving gear is driven to rotate;

the first driven gear is meshed with the driving gear and the second driven gear respectively;

and the second driven gear drives the threaded mold core to coaxially rotate.

4. The mold of claim 1 wherein the core assemblies comprise at least two sets, and the driving device comprises at least two driving members respectively coupled to the threaded cores of each set of core assemblies for driving the threaded cores to rotate.

5. An internally threaded plastic part processing mold as claimed in claim 3 or claim 4 wherein the threaded core is wrapped with a cushion member located in a gap between the driven gear and the threaded core.

6. The mold for processing the internal thread plastic part according to claim 1, wherein the sealing structure comprises a sealing groove and a sealing element arranged on the sealing groove, the cavity of the sealing groove is annular, the sealing element is matched with the sealing groove, and the sealing element protrudes from the inside of the sealing groove to seal the cooling shaft core.

7. The mold of claim 5 wherein the seal is a rubber ring.

8. The mold of claim 1 wherein the product core has uniformly embedded within its walls a workpiece cooling channel, said workpiece cooling channel having a circulating cooling water connection.

9. The mold of claim 1 wherein the bottom of the cavity of the product core has a plurality of protrusions, and wherein the bottom of the cavity of the product core is shaped like a pie and the portion of the cavity of the product core that receives the threaded core is cylindrical.