CN107791460B

CN107791460B - Injection mold with built-in mixed flow

Info

Publication number: CN107791460B
Application number: CN201711190864.4A
Authority: CN
Inventors: 虞伟炳; 李金国
Original assignee: Zhejiang Saihao Industrial Co ltd
Current assignee: Zhejiang Saihao Industrial Co ltd
Priority date: 2017-11-24
Filing date: 2017-11-24
Publication date: 2024-02-20
Anticipated expiration: 2037-11-24
Also published as: CN107791460A

Abstract

The invention provides an injection mold with a built-in mixed flow, and belongs to the technical field of injection molding processing. It has solved the inhomogeneous scheduling technical problem of current molten material temperature that gets into the die cavity. This built-in injection mold who mixes flows, including the mould body, be provided with the runner that is used for the fashioned die cavity of product and is used for accepting external plastic melt in the mould body, be provided with the runner that is used for the intercommunication between runner and the die cavity, be provided with the vortex post in the runner, its characterized in that, the vortex post is located runner width direction's middle part, and the vortex post falls into two branches that supply plastic melt to flow through with runner inner space, and the discharge gate of two branches is close the slope relatively, and the discharge gate of two branches merges in the intercommunication department of runner and die cavity. The inner turbulent flow column can mix the plastic melt and make the temperature uniform.

Description

Injection mold with built-in mixed flow

Technical Field

The invention belongs to the field of injection molding processing, and particularly relates to an injection mold with built-in mixed flow.

Background

The plastic product has the advantages of low cost, firmness, durability and the like, and is widely applied to the production and the living of people. Many of these plastic parts are produced by injection molding, i.e. a mold cavity is provided in an injection mold which corresponds to the shape of the plastic part to be produced, and the injection mold is usually composed of two mold parts. When the injection molding, injection mold is installed on the injection molding machine, and the injection molding machine injects the plastics of molten state into the runner of mould, runner and die cavity intercommunication and intercommunication mouth be the runner, and outside molten plastics flows into the die cavity inside through the runner, then in the die cavity cooling shaping, and then injection mold opens, and the product of moulding plastics completion can deviate from smoothly.

When the molten plastic flows in the runner, the peripheral plastic is in direct contact with the outer wall of the runner, so that the temperature of the peripheral plastic is lower than that of the middle plastic, the temperature distribution of the plastic is not very uniform in the plastic flowing into the die cavity through the gate, obvious flow marks are easily caused on the outer wall of a formed product in the flowing process of the plastic in the die cavity, and the product quality is not up to standard.

The prior Chinese patent with publication number of CN20660575U discloses an improved mold glue inlet, which comprises a glue inlet cavity body, wherein at least a plurality of turbulence protrusions are arranged in the glue inlet cavity body, and the turbulence protrusions are hemispherical or semi-cylindrical, but can only relieve the impact of molten materials and can not effectively solve the effect of uneven temperature of the molten materials.

Disclosure of Invention

The invention aims at the problems existing in the prior art, and provides an injection mold with a built-in mixed flow, which aims at solving the technical problems that: how to keep the temperature of the melt entering the mold cavity uniform.

The aim of the invention can be achieved by the following technical scheme:

the utility model provides an injection mold of built-in mixed flow, includes the mould body, be provided with the die cavity that is used for product shaping in the mould body and be used for accepting external plastic melt's runner, be provided with the runner that is used for the intercommunication between runner and the die cavity, be provided with the vortex post in the runner, its characterized in that, the vortex post is located runner width direction's middle part, the vortex post falls into two branches that supply plastic melt to flow through with runner inner space, and the discharge gate of two branches is closed relatively the slope, and the discharge gate of two branches merges in the intercommunication department of runner and die cavity.

When the plastic melt flows into the pouring gate from the flow passage, the turbulent flow column positioned in the middle part can divide the plastic melt from the middle part, so that the molten materials in the middle of the plastic melt can diffuse to two sides after impacting the turbulent flow column, and in the diffusion process, the molten materials in the middle can be mixed with the molten materials at two sides so as to be mixed with each other. Then, because the discharge ports of the branch channels are relatively close to each other and incline, the plastic melt flowing through the branch channels is mutually opposite to each other in an inclined manner at the position of the discharge ports, and is fully mixed again in the opposite-to-flushing process. Meanwhile, the mixing point is positioned at the communication position of the pouring gate and the die cavity, and the mixed plastic melt directly enters the die cavity to avoid cooling in the runner again. Therefore, the temperature of the plastic melt flowing into the die cavity is uniform, flow marks and the like are not easy to occur on the surface of the product, meanwhile, the whole turbulence structure is simple, only local processing is needed at the pouring gate, and the effect is obvious.

In the injection mold with the built-in mixed flow, the number of the turbulence columns is one, the turbulence columns are prismatic, and the edges of the turbulence columns are opposite to the communicating position of the pouring gate and the runner. The plastic melt under the flowing state is impacted on the turbulent flow column prism, two fluid flows are easy to cut, meanwhile, the molten materials can be directly separated at the cutting position without forming a convolution, the rapid and stable flowing of the fluid is ensured, and the injection molding efficiency is ensured. Two branches can be stably formed by one turbulence column, so that the structure is simple, and the processing is easy.

In the injection mold with the built-in mixed flow, two side surfaces of the pouring gate are concave surfaces which are matched with the outer side surfaces of the turbulent flow columns, and the concave surfaces and the side walls of the turbulent flow columns form two arc-shaped branch passages together. The structure of the concave surface can ensure that enough space is reserved in the branch channel for the plastic melt to flow through, so that the blocking condition is avoided. The arc-shaped branch can enable the molten material to form a stable opposite impact angle at the discharge port of the branch, so that the stability of the molten material in the flowing process is ensured.

In the injection mold with the built-in mixed flow, the two branch structures are symmetrically arranged about the center. Two symmetrical branch roads can be with the flow all separated, and then two equal melt of exit end two branch roads carry out the intermixture, and inside mixed flow maximize when can letting to join like this has guaranteed the inside temperature's of plastics fuse-element degree of consistency.

In the injection mold with the built-in mixed flow, a cooling well for containing plastic melt front cold charge is arranged at the communication part of the pouring gate and the runner. The forefront part of the molten material of the plastic melt injected from each wheel is the front cold material, and the cooling well is a cavity capable of containing part of the plastic melt, so that the cooling well can store the colder plastic melt flowing from the forefront in the primary injection molding process, and the influence of the colder plastic melt on the injection molding is avoided. And the plastic melt with stable subsequent temperature continuously enters the die cavity through the gate, so that the injection molding quality of the product is ensured.

In the injection mold with the built-in mixed flow, a plurality of pouring gates are connected to each mold cavity, a buffer area for shunting is arranged at the tail end of the flow channel, which is communicated with the pouring gates, and the pouring gates are communicated with the buffer area. The plastic melt flowing in the runner can be buffered in the buffer area, mixed with each other and then enter the pouring gate one by one to mix the flow again, so that the uniformity of the temperature of the plastic melt entering the die cavity can be further improved.

In the injection mold with the built-in mixed flow, an ejector rod for ejecting the condensed plastic in the runner is arranged in the buffer zone. After one-time injection molding is finished, the runner and the plastic in the mold cavity are cooled and molded, and the ejector rod can generate the push-out force of the product, so that the plastic in the runner is pushed out, and the next injection molding is convenient to continue. The force application point of the ejection rod is positioned in the buffer area, the plastic area in the buffer area is large, the ejection force can be fully dispersed, and the stable ejection of the product is ensured.

Compared with the prior art, the invention has the following advantages:

1. the plastic flowing in from the outside can be fully mixed in the pouring gate, so that the temperature of the plastic melt flowing into the die cavity is even, and the quality of the injection molded product is better.

2. The whole structure is simple, the processing cost is lower, and the effect is better.

Drawings

Fig. 1 is a schematic structural view of the present embodiment.

Fig. 2 is a partial enlarged view at a of the present embodiment.

In the figure, 1, a die body; 11. a cooling well; 2. a flow passage; 21. a buffer area; 22. an ejector rod; 3. a mold cavity; 4. a gate; 41. a concave surface; 42. branching; 421. an inlet end; 422. an outlet end; 5. a turbulent flow column.

Detailed Description

The following are specific embodiments of the present invention and the technical solutions of the present invention will be further described with reference to the accompanying drawings, but the present invention is not limited to these embodiments.

As shown in fig. 1, an injection mold with mixed flow inside comprises a mold body 1, wherein a mold cavity 3 and a runner 2 are arranged inside the mold body 1, the mold cavity 3 and the runner 2 are arranged on the parting surface of the mold body 1, and the two mold bodies 1 are mutually butted to form a complete and sealed mold cavity 3 and runner 2 inside. The shape of the die cavity 3 is consistent with that of a plastic product to be processed, and when in injection molding processing, the runner 2 is in butt joint with an external injection molding machine, and external plastic melt flows through the runner 2 to enter the die cavity 3 for cooling molding.

As shown in fig. 2, a buffer area 21 is connected to the end of the runner 2, and only a plurality of gates 4 communicating with the cavity 3 are provided on the buffer area 21. The buffer zone 21 is larger in volume, the plastic melt flowing from the runner 2 firstly enters the buffer zone 21, and the plastic melt is mixed in the buffer zone 21 in a buffering flow mode, and enters the die cavity 3 from different pouring gate 4 positions. An ejector rod 22 is arranged in the buffer zone 21, and the ejector rod 22 is connected with an external driving piece and can do free telescopic movement. During injection molding, the top surface of the ejector rod 22 is flush with the surface in the buffer zone 21, and when injection molding is completed and the plastic is cooled and molded, the ejector rod 22 ejects the product in the runner 2.

Wherein, be provided with cooling well 11 on runner 4 and runner 2 intercommunication's lateral wall, every runner 4 corresponds to be provided with a cooling well 11, and the plastics fuse-element front that flows from runner 2 is cooled down easily in the flow process, forms the cold charge, and the cold charge enters into the injection molding quality that can influence the product in the die cavity 3, lets the front cold charge with the plastics fuse-element enter into in the cooling well 11 through the structure of cooling well 11, and follow-up temperature stable plastics can be sustainable enter into the die cavity 3 inside and fill up the die cavity 3 inside like this.

As shown in fig. 2, a turbulence post 5 is disposed at the center of each gate 4, the turbulence post 5 has a quadrangular prism structure and a diamond cross section, wherein concave surfaces 41 are disposed on two sidewalls of the gate 4, and the shape of the concave surfaces 41 corresponds to the shape of the sidewalls of the turbulence post 5. The space in the pouring gate 4 is divided into a left branch 42 and a right branch 42 by the vortex column 5, the two side surfaces of the branch 42 are respectively the concave surface 41 of the pouring gate 4 and the side wall of the vortex column 5, the shape of the concave surface 41 of the pouring gate 4 is corresponding to that of the side wall of the vortex column 5, the distance between the concave surface 41 of the pouring gate 4 and the shape of the side wall of the vortex column 5 are consistent, the widths of all the positions inside the branch 42 formed in this way are equal, and therefore the plastic melt can be guaranteed to flow smoothly, and the blocking condition is avoided.

The two ends of the branch 42 are respectively an inlet end 421 and an outlet end 422, the inlet end 421 is positioned at the communication position of the gate 4 and the buffer cavity, and the outlet ends 422 of the two branch 42 are intersected at the communication position of the gate 4 and the die cavity 3. The inlet ends 421 of the two branches 42 are of uniform width. The melt exiting the outlet ends 422 of the two branches 42 meet at an angle other than 0, preferably 45-90, so that mixing is most efficient without affecting the flow of melt.

The two branch passages 42 are in a ring shape as a whole, and the two branch passages 42 are symmetrically arranged with each other and have equal widths. When entering the pouring gate 4, the plastic melt firstly impacts the turbulent flow column 5, the turbulent flow column 5 shunts the plastic melt, the plastic melt enters the two equal branch passages 42, the width of the branch passages 42 is uniform, the plastic melt flows stably, and the blocking condition can not occur. At the same time, the two branches 42 finally meet, and the plastic melt again generates mixed flow, so that the peripheral plastic melt with lower original temperature and the plastic melt with higher middle temperature can be uniformly mixed, and finally enter the die cavity 3.

During injection molding, the front cold charge of the plastic melt can be stored in the cooling well 11, avoiding that it affects the quality of the injection molded product. The plastic melt continuously fed in the runner 2 is firstly subjected to large-scale buffer mixing in the buffer zone 21, finally enters the pouring gate 4, and in the pouring gate 4, the turbulent flow column 5 divides and mixes the central fluid of the plastic melt, so that the temperature of the plastic melt entering the die cavity 3 is balanced, and the injection molded product is stable.

The specific embodiments described herein are offered by way of example only to illustrate the spirit of the invention. Those skilled in the art may make various modifications or additions to the described embodiments or substitutions thereof without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Although 1, the mold body is used more herein; 11. a cooling well; 2. a flow passage; 21. a buffer area; 22. an ejector rod; 3. a mold cavity; 4. a gate; 41. a concave surface; 42. branching; 5. turbulent flow column, etc., but does not exclude the possibility of using other terms. These terms are used merely for convenience in describing and explaining the nature of the invention; they are to be interpreted as any additional limitation that is not inconsistent with the spirit of the present invention.

Claims

1. The utility model provides an injection mold of built-in mixed flow, includes mould body (1), be provided with in mould body (1) be used for the fashioned die cavity (3) of product and be used for accepting runner (2) of external plastic melt, be provided with runner (4) that are used for the intercommunication between runner (2) and die cavity (3), be provided with vortex post (5) in runner (4), a serial communication port, vortex post (5) are located the middle part of runner (4) width direction, vortex post (5) divide into two branch ways (42) that supply plastic melt to flow through with runner (4) inner space, the discharge gate of two branch ways (42) is close the slope relatively, and the discharge gate of two branch ways (42) is joined in the intercommunication department of runner (4) and die cavity (3), be used for on runner (2) with the end of runner (4) intercommunication have buffer (21) that are used for the reposition of redundant personnel, the intercommunication department of runner (4) and runner (2) is provided with cooling well (11) that holds before the plastic melt, cooling well (11) distributes and is in the corresponding one of each of two sides (4) and is provided with buffer (11).

2. The injection mold with mixed flow built-in according to claim 1, wherein the number of the turbulence columns (5) is one, the turbulence columns (5) are prismatic, and edges of the turbulence columns (5) are opposite to a communicating position of the pouring gate (4) and the runner (2).

3. The injection mold with mixed flow built-in according to claim 1, wherein both side surfaces of the gate (4) are concave surfaces (41) corresponding to the outer side surfaces of the turbulent flow column (5), and the concave surfaces (41) and the side walls of the turbulent flow column (5) form two arc-shaped branch passages (42) together.

4. The injection mold of claim 1, wherein the two branch structures (42) are symmetrically disposed about the center.

5. The injection mold with built-in mixed flow according to any one of claims 1 to 4, wherein a plurality of gates (4) are connected to each cavity (3), and the gates (4) are communicated with the buffer (21).

6. The injection mold with built-in mixed flow according to claim 5, wherein an ejector rod (22) for ejecting condensed plastic in the runner (2) is provided in the buffer zone (21).