CN216782524U - Valve needle guide structure and injection mold - Google Patents

Abstract

The utility model relates to a valve needle guide structure and an injection mold. The valve needle guide structure comprises a flow distribution plate, a guide piece and a cover body, wherein a through hole which penetrates through the flow distribution plate up and down is formed in the flow distribution plate, and a first annular groove is formed in the top of the through hole; the guide piece is of a rotary body structure with a central guide hole, the outer peripheral surface of the guide piece is a convex arc surface, and the guide piece is partially accommodated in the first annular groove and can be axially deflected and adjusted through the matching of the arc surface and the first annular groove; the cover body is provided with a clearance hole which penetrates through the cover body from top to bottom, a second annular groove opposite to the first annular groove is formed in the bottom of the clearance hole, and the cover body covers the guide piece and is fixedly connected with the flow distribution plate to limit axial deflection of the guide piece. The utility model can quickly fix the guide piece at the position of the central guide hole and the position of the same central axis line of the ejection hole of the hot runner nozzle, has simple structure and low requirement on processing precision and is convenient and quick to install.

Description

Valve needle guide structure and injection mold

Technical Field

The utility model belongs to the technical field of molds, and particularly relates to a valve needle guide structure and an injection mold.

Background

The hot runner system is mainly used as one part of an injection mold, and has the functions of keeping plastic in a molten state all the time in the injection molding process and guiding the molten plastic to different mold cavities, so that the waste of water gap materials is avoided, the injection molding pressure is favorably reduced, the injection molding period is shortened, and the product quality is improved.

The structure of the existing hot runner system is shown in fig. 1, and mainly includes a guide body 102, a fixing sleeve 103 and a hot runner nozzle 104, the guide body 102 is fixedly mounted on the top surface of the manifold 101 through the fixing sleeve 103, the hot runner nozzle 104 is disposed on the bottom surface of the manifold 101, a through hole 105 communicated with the guide body 102 and the hot runner nozzle 104 is formed between the top surface and the bottom surface of the manifold 101, a valve needle 107 of the hot runner nozzle 104 passes through the through hole 105 and then is slidably connected with a central guide hole of the guide body 102, a branch runner 106 communicated with the through hole 105 is formed in the manifold 101, a molten material enters the hot runner nozzle 104 from the branch runner 106 through the through hole 105, during injection molding, the valve needle 107 moves upwards to open the ejection hole 108 of the hot runner nozzle 104, the melt is ejected from the ejection hole 108 and enters the mold cavity from the mold core gate 109, and the valve needle 107 moves downwards to the ejection hole 108 to be closed after the injection molding is finished; valve needle 107 is guided by a central guide bore of guide body 102 as it moves up and down between the open and closed positions to prevent valve needle 107 from deflecting and damaging the interior of hot runner nozzle 104.

However, due to processing and assembly errors, it cannot be completely ensured that the central guide hole of the guide body 102 and the ejection hole 108 of the hot runner nozzle 104 are located on the same axis, as shown in fig. 2, the valve needle 107 may swing during the movement process to damage the ejection hole 108 of the hot runner nozzle 104, or even damage the mold core gate 109, thereby affecting the surface appearance of the molded product, causing problems such as gate over-height and gate non-smooth glue discharge, resulting in an increase in the production rejection rate, an increase in the production cost, and an impact on the production efficiency.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the defects in the prior art at least to a certain extent and provides a valve needle guide structure and an injection mold.

In order to achieve the above object, the present invention provides a valve needle guiding structure, which is applied in an injection mold, and comprises:

the flow distribution plate is provided with a through hole which penetrates through the flow distribution plate up and down, and a first annular groove surrounding the periphery of the through hole is formed at the top of the through hole;

the guide piece is of a rotary body structure with a central guide hole, and the central guide hole is used for guiding the sliding direction of the valve needle; the outer peripheral surface of the guide piece is a convex arc surface, and the guide piece part is accommodated in the first annular groove and can be axially deflected and adjusted through the matching of the arc surface and the first annular groove;

the cover body is provided with a clearance hole which penetrates from top to bottom and is used for avoiding the valve needle, a second annular groove which surrounds the periphery of the clearance hole and is opposite to the first annular groove is formed at the bottom of the clearance hole, the cover body is covered on the guide piece and is fixedly connected with the flow distribution plate, so that the first annular groove and the second annular groove are clamped on the arc surface from top to bottom to limit the axial deflection of the guide piece.

Optionally, the arc surface of the guide is formed by rotating a segment of arc around the central axis of the central guide hole.

Optionally, the center of the circular arc is located outside the central axis.

Optionally, the first annular groove and the second annular groove are both arc-shaped grooves matched with the arc surface, and the radians of the first annular groove and the second annular groove are both smaller than 90 °.

Optionally, one end of the guide piece protrudes from the clearance hole from the periphery of the central guide hole to form a tubular first guide part.

Optionally, the other end of the guide piece protrudes from the periphery of the central guide hole to form a second guide part extending into the through hole.

Optionally, the top of the flow distribution plate is provided with a mounting hole communicated with the through hole, the first annular groove is formed between the bottom surface of the mounting hole and the through hole, and the cover body is fixedly mounted in the mounting hole.

Optionally, the cover body has a cross-sectional dimension matched with the cross-sectional dimension of the mounting hole, and a top portion of the cover body protrudes radially outward to form a flange, and the flange is fixed on the top surface of the flow distribution plate through a fastener.

Optionally, a runner is formed in the flow distribution plate, one end of the runner is communicated with a main runner of the injection mold, and the other end of the runner is communicated with the through hole.

The utility model also provides an injection mold, which comprises the valve needle guide structure, the bottom surface of the flow distribution plate is provided with a hot runner nozzle communicated with the through hole, and a valve needle of the hot runner nozzle is arranged in the central guide hole in a penetrating manner.

The guide piece is clamped and fixed by the first annular groove and the second annular groove so as to be fixed at the position where the central guide hole and the ejection hole are in the same central axis; so guaranteed that the valve needle can be accurate slide to the blowout hole under the guiding action of center guiding hole to avoid the runner damage and appear influencing the problem of product appearance, improved injection mold's finished product yield, and simple structure, it is low to the machining precision requirement, simple to operate is swift.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a valve pin guide structure of a prior art hot runner system;

FIG. 2 is a schematic view of the valve pin guide structure of FIG. 1 showing deflection of the valve pin due to machining or installation errors;

figure 3 is a cross-sectional view of an embodiment of the valve pin guidance structure of the present invention;

FIG. 4 is an enlarged view of portion A of FIG. 3;

description of the main elements:

101. a flow distribution plate; 102. a guide body; 103. fixing a sleeve; 104. a hot runner nozzle; 105. a through hole; 106. a shunt channel; 107. a valve needle; 108. an ejection hole; 109. a mold core sprue;

10. a splitter plate; 11. a through hole; 12. a first annular groove; 13. a shunt channel; 14. mounting holes;

20. a guide member; 21. a central guide hole; 22. a circular arc surface; 23. a first guide portion; 24. a second guide portion;

30. a cover body; 31. avoiding a void; 32. a second annular groove; 33. a flange;

40. a hot runner nozzle; 41. a flow passage hole; 42. an ejection hole; 50. a valve needle; 60. and a mold core sprue.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be illustrative of the present invention and should not be construed as limiting the present invention, and all other embodiments that can be obtained by one skilled in the art based on the embodiments of the present invention without inventive efforts shall fall within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "circumferential," "radial," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

Referring to fig. 3 and 4, a valve pin guiding structure for an injection mold with a hot runner system according to an embodiment of the present invention includes a splitter plate 10, a guide 20, and a cover 30.

A through hole 11 which penetrates through the flow distribution plate 10 from top to bottom is formed in the flow distribution plate 10, a flow distribution channel 13 is formed in the flow distribution plate 10, one end of the flow distribution channel 13 is communicated with a main flow channel of an injection mold, and the other end of the flow distribution channel 13 is communicated with the through hole 11. The top of the through-hole 11 is formed with a first annular groove 12 around the periphery of the through-hole 11.

The guide 20 is a solid of revolution structure having a central guide hole 21, the central guide hole 21 is used for guiding the sliding direction of the valve needle 50; the outer peripheral surface of the guide 20 is a convex arc surface 22, and the guide 20 is partially accommodated in the first annular groove 12 and can be axially deflected and adjusted through the matching of the arc surface 22 and the first annular groove 12.

The cover body 30 is provided with a clearance hole 31 which penetrates up and down and is used for avoiding the valve needle 50, a second annular groove 32 which surrounds the periphery of the clearance hole 31 and is opposite to the first annular groove 12 is formed at the bottom of the clearance hole 31, the cover body 30 is covered on the guide member 20 and is fixedly connected with the flow distribution plate 10, and the first annular groove 12 and the second annular groove 32 vertically clamp the arc surface 22 so as to limit the axial deflection of the guide member 20.

The injection mold with the hot runner system is provided with a hot runner nozzle 40 communicated with the through hole 11 on the bottom surface of the flow distribution plate 10, a runner hole 41 for molten material to pass through is arranged in the hot runner nozzle 40, and the upper end of the runner hole 41 is connected with the through hole 11, so that the molten material injected from a main runner can sequentially pass through the flow distribution channel 13 and the through hole 11 and enter the runner hole 41; and the lower end of the runner hole 41 is gradually reduced to form an ejection hole 42, the ejection hole 42 is communicated with a die core sprue 60 of the injection mold, the dissolved material in the runner hole can be injected into a molding cavity of the injection mold from the die core sprue 60 through the ejection hole 42, and the mold is opened after the dissolved material in the molding cavity is cooled and solidified to take out a molded product.

In this embodiment, the outer diameter of the valve needle 50 of the hot runner nozzle 40 is adapted to the diameter of the ejection hole 42, and when the lower end of the valve needle 50 slides downward and is located in the ejection hole 42, the valve needle 50 blocks the ejection hole 42 to cut off the communication between the runner hole 41 and the mold core gate 60; when injection molding is required, the valve needle 50 is driven to move upwards to open the ejection hole 42, so that the solvent in the channel hole 41 can be ejected from the ejection hole 42 and injected into the molding cavity from the mold core gate 60, thereby realizing the injection molding of the product.

It should be understood that the injection mold is provided with a driving device (not shown) above the diversion plate 10, the upper end of the valve needle 50 is connected with the driving device, the lower end passes through the central guide hole 21 and extends into the flow passage hole 41, the central guide hole 21 provides a guiding function for the valve needle 50, so that the driving device can be accurately inserted into the ejection hole 42 when the valve needle 50 is driven to move downwards to achieve the purpose of blocking.

It should be noted that the lower end of the valve needle 50 shown in fig. 3 has two position states, the position state of the valve rod 50 shown on the left side of the central line is a closed position state, and the lower end of the valve rod 50 simultaneously seals the ejection hole 42 and the mold core gate 60 to close the communication between the flow passage hole 41 and the molding cavity; the position state of the valve rod 50 shown on the right side of the center line is an open position state, that is, the lower end of the valve rod 50 moves upwards and retracts into the flow passage hole 41 to open the ejection hole 42 and the mold core gate 60, and at this time, the molten material can sequentially pass through the ejection hole 42 and the mold core gate 60 from the flow passage hole 41 and enter the molding cavity to realize injection molding.

According to the valve needle guiding structure of the embodiment of the utility model, in practical application, the guiding element 20 is firstly installed on the first annular groove 12 of the splitter plate 10, then the lower end of the valve needle 50 sequentially passes through the clearance hole 31 of the cover body 30, the central guiding hole 21 of the guiding element 20, the through hole 11 of the splitter plate 10 and the flow passage hole 41 of the hot runner nozzle 40 until extending into the spouting hole 42, at this time, the axial deflection of the guiding element 20 can be adjusted to the condition that the central guiding hole 21 and the spouting hole 42 are positioned on the same central axis by utilizing the matching of the arc surface 22 of the guiding element 20 and the first annular groove 12, then the cover body 30 is fixed on the splitter plate 10, and the guiding element 20 is clamped and fixed by utilizing the first annular groove 12 and the second annular groove 32 so as to fix the guiding element 20 at the position that the central guiding hole 21 and the spouting hole 42 are positioned on the same central axis; with the structure, the valve needle 50 can accurately slide to the ejection hole 42 under the guiding action of the central guide hole 21, so that the problem that the appearance of a product is influenced due to the damage of the pouring gate is avoided, the finished product yield of the injection mold is improved, the structure is simple, the requirement on the processing precision is low, and the installation is convenient and rapid.

Of course, in other embodiments, the cover body 30 may be connected to the flow distribution plate 10 in advance, so that the guide member 20 is movably accommodated between the first annular groove 12 and the second annular groove 32, the needle 50 is inserted into the central guide hole 21 and the spouting holes 42 to achieve the concentric positioning calibration, and then the cover body 30 is locked on the flow distribution plate 10, so that the first annular groove 12 and the second annular groove 32 clamp and fix the guide member 20 up and down; illustratively, the cover 30 may be threadably attached to the manifold 10, and may be installed with the guide 20 in a relaxed position relative to the first and second annular grooves 12, 32, and then tightened to secure the guide 20 after adjustment of the axial deflection of the guide by the needle 50.

In one embodiment, the arc surface 22 of the guide 20 is formed by rotating a segment of arc around the central axis of the central guide hole 21, that is, the outer diameter of the guide 20 is a structure with a large middle and two small ends; preferably, the first annular groove 12 and the second annular groove 32 are both arc-shaped grooves matched with the arc surface 22, and the radians of the first annular groove 12 and the second annular groove 32 are both smaller than 90 °.

In this way, when the guide 20 is in a loose state relative to the diversion plate 10 and the cover 30, the arc surface 22 can axially deflect by matching with the first annular groove 12 and the second annular groove 32, so as to achieve the purpose of quickly adjusting the guide 20; when the cover 30 is locked to the splitter plate 10 such that the first annular groove 12 and the second annular groove 32 clamp the fixed guide 20, the first annular groove 12 fits in the lower half of the arc surface 22 of the guide 20, and the second annular groove 32 fits in the upper half of the arc surface 22 of the guide 20.

In order to ensure the stability of the clamping of the cover 30 and the splitter plate 10 to the guide 20, the center of the circular arc is located outside the central axis in the embodiment; that is to say, the arc surface 22 of the guide 20 is an aspheric surface, so that the guide 20 can axially deflect when being in a loose state relative to the splitter plate 10 and the cover 30, and when the cover 30 and the splitter plate 10 clamp and fix the guide 20, the guide 20 is prevented from axially deflecting due to vibration during use, and stable guiding is ensured. In other embodiments, the center of the arc may be on the central axis, that is, the arc surface 22 of the outer periphery of the guide 20 is a spherical surface, which also enables the guide 20 to achieve axial deflection adjustment in the relaxed state, but in this way, the strength requirement for pressing the cover 30 against the guide 20 is high, so as to avoid axial deflection of the guide 20 in the fixed state.

In one embodiment, the guide member 20 has one end protruding from the periphery of the central guide hole 21 from the clearance hole 31 to form a first guide portion 23 in a tubular shape, and the other end protruding from the periphery of the central guide hole 21 to form a second guide portion 24 protruding into the through hole 11.

In this way, the axial length of the central guide hole 21 can be extended by the arrangement of the first guide part 23 and/or the second guide part 24, and the guide accuracy of the guide 20 to the valve needle 50 is further improved; in the present embodiment, the hole diameter of the clearance hole 31 is larger than the outer diameter of the first guide portion 23, and the hole diameter of the through hole 11 is larger than the outer diameter of the second guide portion 24, so that the guide 20 can achieve axial deflection adjustment within a certain range.

In one embodiment, the top of the flow distribution plate 10 is opened with a mounting hole 14 communicating with the through hole 11, a first annular groove 12 is formed between the bottom surface of the mounting hole 14 and the through hole 11, and the cover 30 is fixedly mounted in the mounting hole 14. Thus, the guide 20 is closer to the spouting hole 42, the distance between the central guide hole 21 and the spouting hole 42 is reduced, the guide accuracy of the guide 20 is improved, and the guide 20 and the cover 30 are accommodated in the mounting hole 14 to optimize the structure of the injection mold.

Further, in order to improve the fixing strength of the cover body 30 and the flow distribution plate 10, in the embodiment, the cross-sectional size of the cover body 30 is matched with the cross-sectional size of the mounting hole 14, a flange 33 is formed by protruding the top of the cover body 30 radially outwards, and the flange 33 is fixed on the top surface of the flow distribution plate 10 through a fastener. Of course, the cover 30 may be provided with external threads on the outer periphery thereof and internal threads on the inner peripheral wall of the mounting hole 14, so that the cover 30 can be screwed into the mounting hole 14 to press and fix the guide 20.

The utility model further provides an injection mold, which comprises the valve needle guide structure, the specific structure of the valve needle guide structure refers to the embodiments, and as the injection mold adopts all the technical schemes of all the embodiments, the injection mold at least has all the beneficial effects brought by the technical schemes of the embodiments, and the details are not repeated herein.

In addition, the utility model also provides a valve needle guiding and positioning method, which is applied to the valve needle guiding structure and comprises the following steps: in a state in which the guide 20 is axially deflectable adjustable relative to the diverter plate 10; the valve needle 50 of the hot runner nozzle 40 is arranged in the clearance hole 31, the central guide hole 21 and the through hole 11 in a penetrating way, and the lower end of the valve needle 50 penetrates out of the through hole 11 and enters the runner hole 41; when the lower end of the valve needle 50 slides to the ejection hole 42 of the hot runner nozzle 40, the axial deflection of the guide 20 can be adjusted to the condition that the central guide hole 21 and the ejection hole 42 are on the same central axis by using the matching of the arc surface 22 of the guide 20 and the first annular groove 12, and then the cover body 30 is fixed to the splitter plate 10 to compress the guide 20, so that the central guide hole 21 is axially positioned to the position on the same central axis as the ejection hole 42.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

In view of the above description of the technical solutions provided by the present invention, those skilled in the art will recognize that there may be variations in the technical solutions and the application ranges according to the concepts of the embodiments of the present invention, and in summary, the content of the present specification should not be construed as limiting the present invention.

Claims (10)

1. The utility model provides a needle guide structure, is applied to in injection mold, its characterized in that includes:

the flow distribution plate is provided with a through hole which penetrates through the flow distribution plate up and down, and a first annular groove surrounding the periphery of the through hole is formed at the top of the through hole;

the guide piece is of a rotary body structure with a central guide hole, and the central guide hole is used for guiding the sliding direction of the valve needle; the outer peripheral surface of the guide piece is a convex arc surface, and the guide piece part is accommodated in the first annular groove and can be axially deflected and adjusted through the matching of the arc surface and the first annular groove;

the cover body is provided with a clearance hole which penetrates through the cover body from top to bottom and is used for avoiding the valve needle, a second annular groove which surrounds the periphery of the clearance hole and is opposite to the first annular groove is formed at the bottom of the clearance hole, the cover body covers the guide piece and is fixedly connected with the flow distribution plate, so that the first annular groove and the second annular groove vertically clamp the arc surface to limit the axial deflection of the guide piece.

2. The valve pin guide structure of claim 1, wherein the arc surface of the guide member is formed by rotating an arc around the central axis of the central guide hole.

3. The valve needle guiding structure of claim 2 wherein the center of the arc is located outside the central axis.

4. The valve needle guiding structure of claim 2 wherein the first annular groove and the second annular groove are both circular arc grooves adapted to the circular arc surface, and the radians of the first annular groove and the second annular groove are both less than 90 °.

5. The valve needle guide structure of claim 1, wherein one end of the guide member protrudes from the periphery of the central guide hole to form a tubular first guide portion.

6. The needle guide structure of claim 5 wherein the other end of the guide member is formed with a second guide portion protruding from the periphery of the central guide hole and extending into the through hole.

7. The needle guide structure of claim 1, wherein a mounting hole communicating with the through hole is formed at the top of the flow distribution plate, the first annular groove is formed between the bottom surface of the mounting hole and the through hole, and the cover body is fixedly mounted in the mounting hole.

8. The needle guide structure of claim 7 wherein the cross-sectional dimension of the cover body is adapted to the cross-sectional dimension of the mounting hole, and the top of the cover body is formed with a flange protruding radially outward, and the flange is fixed to the top surface of the diverter plate by a fastener.

9. The valve pin guide structure according to claim 1, wherein a branch flow passage is formed in the branch flow plate, one end of the branch flow passage communicates with a main flow passage of the injection mold, and the other end communicates with the through hole.

10. An injection mold, comprising the valve needle guide structure according to any one of claims 1 to 9, wherein the bottom surface of the flow distribution plate is provided with a hot runner nozzle communicating with the through hole, and a valve needle of the hot runner nozzle is inserted into the central guide hole.

Images