CN212072801U

CN212072801U - Needle valve type hot runner structure

Info

Publication number: CN212072801U
Application number: CN202020576978.3U
Authority: CN
Inventors: 王琳
Original assignee: Shenzhen Lianhua Yisheng Industry Co ltd
Current assignee: Shenzhen Lianhua Yisheng Industry Co ltd
Priority date: 2020-04-17
Filing date: 2020-04-17
Publication date: 2020-12-04
Anticipated expiration: 2030-04-17

Abstract

The application relates to a needle valve type hot runner structure, which comprises a front mould, a rear mould, a valve needle, a flow distribution plate, a nozzle head, a mould core, a small slide block and a small slide shovel, wherein the front mould and the rear mould surround to form a cavity, and an injection molding hole is formed in the front mould; a glue dividing channel is arranged in the flow dividing plate; the nozzle head is fixedly connected with the flow distribution plate, a flow channel is arranged in the nozzle head, and the flow channel is communicated with the glue distribution channel; the valve needle penetrates through the flow distribution plate and is lifted or falls down under the driving of external force so as to block the flow passage and stop injecting the glue or open the flow passage to realize injecting the glue; the mold core is fixed on the rear mold and at least partially extends into the cavity; the small slide block is fixed on the mold core and movably connected with the mold core; little line position shovel machine at least part stretches into in the mold core to sliding connection in mold core, little line position slider sliding connection in little line position shovel machine, when little line position shovel machine slides relative mold core, order about little line position slider and move relative mold core. The needle valve type hot runner structure can be fully injected under low pressure.

Description

Needle valve type hot runner structure

Technical Field

The application relates to the field of injection molding, in particular to a needle valve type hot runner structure.

Background

PCTG is a transparent plastic, an amorphous copolyester. A common comonomer used in PCTG is 1, 4-Cyclohexanedimethanol (CHDM), commonly known as polyethylene terephthalate-1, 4-cyclohexanedimethanol ester. It is a product obtained by Polycondensation of Terephthalic Acid (PTA), Ethylene Glycol (EG) and 1, 4-Cyclohexanedimethanol (CHDM) through an ester exchange method. PCTG has better viscosity, transparency, color, chemical agent resistance and stress whitening resistance, can be quickly thermoformed or extrusion blow molded, and has better viscosity than acrylic acid (acrylic). The product is highly transparent, has excellent impact resistance, is particularly suitable for molding thick-wall transparent products, has excellent processing and molding performance, can be designed into any shape according to the intention of designers, and can be molded by adopting the traditional molding methods such as extrusion, injection molding, blow molding, plastic suction and the like, thereby being widely applied.

However, the PCTG material has poor toughness, and when the injection molding is performed, if the pressure is too high in the injection molding process, the product is cracked and discarded, but the conventional hot runner structure is difficult to complete the injection molding of the PCTG at low pressure.

SUMMERY OF THE UTILITY MODEL

Based on this, it is necessary to provide a needle valve type hot runner structure, which is directed to the problem that the conventional hot runner structure is difficult to complete injection molding of PCTG at low pressure.

The needle valve type hot runner structure comprises a front mold, a rear mold, a valve needle, a flow distribution plate, a nozzle head, a mold core, a small slide block and a small slide shovel machine, wherein the front mold, the rear mold, the valve needle, the flow distribution plate, the nozzle head, the mold core, the small slide block and the small slide shovel machine are arranged on the mold core

The front die and the rear die are fixed with each other and form a cavity in a surrounding manner, and the front die is provided with an injection molding hole;

a glue dividing channel is arranged in the flow dividing plate;

the nozzle head is fixedly connected with the splitter plate, a flow channel is arranged in the nozzle head, and the flow channel is communicated with the glue distributing channel;

the valve needle penetrates through the flow distribution plate and is lifted or falls down under the driving of external force so as to block the flow passage and stop injecting the glue or open the flow passage to realize injecting the glue;

the mold core is fixed on the rear mold, at least partially extends into the cavity and is used for molding a product;

the small slide block is fixed on the mold core and movably connected to the mold core;

the small slide shoveling machine at least partially extends into the die core and is connected with the die core in a sliding mode, the small slide sliding block is connected with the small slide shoveling machine in a sliding mode, and when the small slide shoveling machine slides relative to the die core, the small slide sliding block is driven to move relative to the die core.

In one embodiment, one end of the rear die, which is far away from the front die, is provided with a first through hole, and the die core is detachably assembled at the first through hole.

In one embodiment, a sliding groove is formed in the mold core, and at least part of the small slide shovel is accommodated in the sliding groove and can slide in the sliding groove under the driving of external force;

the die core is also provided with a through hole which penetrates through the die core in the thickness direction, the chute is communicated with the die cavity through the through hole, and the small slide block is assembled in the through hole.

In one embodiment, a slide way is arranged on the small slide shovel machine, and the small slide block is at least partially embedded into the slide way and is in sliding fit with the small slide shovel machine; when the small slide shoveling machine slides in the sliding groove, the small slide shoveling machine drives the small slide block to move in the through hole.

In one embodiment, the moving direction of the small-row shovel machine is defined as a first direction, and the length direction of the slide way is obliquely arranged relative to the first direction.

In one embodiment, a valve needle guide sleeve is arranged at the end of the nozzle head far away from the flow distribution plate and at the tail end of the flow passage, a water gap is arranged in the valve needle guide sleeve and communicated with the flow passage, and the valve needle penetrates through the flow distribution plate and the nozzle head to enter the water gap.

In one embodiment, the maximum width of the nozzle is greater than the width of the flow passage.

In one embodiment, an injection groove is formed in the end face, away from the rear mold, of the front mold, an injection hole is formed in the bottom of the injection groove, the injection groove is communicated with the cavity through the injection hole, and the nozzle head is at least partially accommodated in the injection groove.

In one embodiment, the valve needle guide sleeve is arranged in abutment with one end of the injection molding hole, so that the flow passage of the nozzle head is directly communicated with the cavity.

In one embodiment, the device further comprises a pushing block, a second through hole is formed in the rear die, and the pushing block is assembled in the second through hole and movably connected to the rear die; the pushing block is used for pushing the injection product to be separated from the cavity after the injection product is cooled.

According to the needle valve type hot runner structure, the small slide block is added at the mold core, and is firmly clamped on the small slide shovel machine to form a closed cavity in the glue injection process, so that a product can be fully injected under low pressure.

Drawings

FIG. 1 is a schematic structural view of a needle valve type hot runner structure according to an embodiment of the present application;

FIG. 2 is an exploded view of a needle valve hot runner configuration according to an embodiment of the present application;

FIG. 3 is a schematic cross-sectional view of a needle valve hot runner configuration according to an embodiment of the present application;

FIG. 4 is another schematic cross-sectional view of a needle valve hot runner configuration according to an embodiment of the present application;

FIG. 5 is a partial enlarged view of portion B of bitmap 4;

FIG. 6 is a schematic cross-sectional view of the front and rear molds of a needle valve hot runner configuration according to an embodiment of the present application;

FIG. 7 is a schematic structural diagram of a mold core of a needle valve type hot runner structure according to an embodiment of the present application;

fig. 8 is a schematic cross-sectional view of a mold core of a needle valve type hot runner structure according to an embodiment of the present application.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

According to the needle valve type hot runner structure of each embodiment of the application, the small slide block is added at the mold core, and the small slide block is firmly clamped on the small slide shovel machine to form a closed cavity in the glue injection process, so that a product can be fully injected under low pressure.

The needle valve type hot runner structure of the embodiments of the present application is described in detail below with reference to the accompanying drawings.

Referring to fig. 1 to 4, a needle valve type hot runner structure 10 according to an embodiment of the present application is exemplarily shown, the needle valve type hot runner structure 10 includes a front mold 112, a rear mold 114, a valve needle 120, a splitter plate 130, a nozzle head 140, a mold core 150, a small slide block 160 and a small slide shovel 170, the front mold 112 and the rear mold 114 are fixed to each other and enclose to form a mold cavity 10a, a splitter channel in the splitter plate 130 is communicated with the nozzle head 140, PCTG material enters the mold cavity 10a from the nozzle head 140, the mold core 150 is fixed to the rear mold 114 and at least partially extends into the mold cavity 10a for molding a product, the small slide block 160 is fixed to the mold core 150 and is movably connected to the mold core 150, the small slide shovel 170 extends at least partially into the mold core 150 and is slidably connected to the mold core 150, the small slide block 160 is slidably engaged with the small slide shovel 170, when the small slide shovel 170 slides relative to the mold core 150, the small slide 160 moves on the small slide shovel 170 and causes the small slide 160 to move relative to the mold core 150.

With reference to fig. 6, the front mold 112 includes a first end surface and a second end surface opposite to each other, wherein the first end surface is an end surface close to the rear mold 114, and the second end surface is an end surface far from the rear mold 114. The first end surface is provided with a first groove 112a, and the first groove 112a is a part of the cavity 10a when the front mold 112 and the rear mold 114 are fixed. The second end face is provided with an injection molding groove 112b, the bottom of the injection molding groove 112b is provided with an injection molding hole 112c, and the injection molding groove 112b is communicated with the first groove 112a through the injection molding hole 112 c. When the nozzle head 140 injects the glue, the injection hole 112c is aligned, and PCTG material is injected into the injection hole 112c, and enters the first groove 112 a/the cavity 10a through the injection hole 112 c.

One end of the rear mold 114 close to the front mold 112 is provided with a second groove 114a, and when the front mold 112 and the rear mold 114 are fixed, the first groove 112a and the second groove 114a surround to form a cavity 10 a. One end of the rear die 114, which is far away from the front die 112, is provided with a first through hole 114b, the second groove 114a is communicated with the first through hole 114b, the die core 150 is assembled and fixed in the first through hole 114b and at least partially extends into the second groove 114a, and when the PCTG material enters the die cavity 10a, the side wall of the die cavity 10a and the die jointly complete the forming of the product.

Referring to fig. 3, the diversion plate 130 is connected to the main glue channel, a glue dividing channel (not shown) is disposed in the diversion plate 130, the glue dividing channel is communicated with the main glue channel, and the PCTG material flows into the glue dividing channel from the main glue channel.

Referring to fig. 3, the nozzle head 140 is fixedly connected to the splitter plate 130, the flow channel 140a is disposed in the nozzle head 140, the flow channel 140a is communicated with the glue dividing channel, and when the nozzle head 140 is in the glue injecting state, the PCTG material enters the flow channel 140a of the nozzle head 140 through the glue dividing channel and is injected from the flow channel 140 a.

The valve needle 120 penetrates through the diversion plate 130 and is lifted or dropped by an external force to block the flow passage 140a to stop injecting the glue or open the flow passage 140a to realize injecting the glue.

Referring to fig. 2 and 5, in one or more embodiments, a valve needle guide sleeve 180 is disposed at an end of the nozzle tip 140 away from the diversion plate 130 and located at a distal end of the flow passage 140a, a water gap 180a is disposed in the valve needle guide sleeve 180, the water gap 180a is communicated with the flow passage 140a, and the valve needle 120 penetrates through the diversion plate 130 and the nozzle tip 140 to enter the water gap 180a, so that the injection control of the nozzle tip 140 is realized through cooperation of the valve needle 120, the flow passage 140a and the water gap 180 a.

Specifically, after the PCTG material is melted and plasticized by the heater, the valve pin 120 is controlled to be lifted, the flow channel 140a is opened, and the PCTG material enters the flow channel 140a along the glue dividing channel and is ejected from the water gap 180a of the valve pin guide sleeve 180. After the product injection is completed, the valve needle 120 is controlled to fall to block the flow passage 140a, and during the falling of the valve needle 120, the PCTG glue is adhered to the valve needle 120 and forms a film at the water gap 180a, and the film blocks one end of the flow passage 140a close to the water gap 180 a. Before the injection molding is performed again, the valve needle 120 is heated together, the film at the water gap 180a is melted, the valve needle 120 is lifted, and the runner 140a is opened, so that the injection molding can be performed again. The arrangement of the valve needle guide sleeve 180 and the water gap 180a prevents the glue leakage phenomenon on one hand, and prevents the PCTG glue from adhering to the nozzle head 140 on the other hand.

Referring to fig. 5, in one or more embodiments, the maximum width of the nozzle 180a is greater than the width of the flow channel 140a, so that a better glue leakage prevention effect can be achieved, as long as the valve needle 120 does not extend out of the valve needle guide sleeve 180, the PCTG material will not flow out, and the PCTG material is completely retained in the nozzle head 140 and the valve needle guide sleeve 180.

Referring to fig. 5, in one or more embodiments, the nozzle head 140 is at least partially received in the injection groove 112b, and the valve needle guide sleeve 180 is disposed in contact with one end of the injection hole 112c, so that the flow channel 140a of the nozzle head 140 is directly communicated with the mold cavity 10a, and thus, during injection, PCTG material can be directly injected into the mold cavity 10a from the injection hole 112c after being injected from the nozzle head 140. The direct connection between the runner 140a of the nozzle head 140 and the cavity 10a prevents the PCTG material from being carbonized and deposited on the splitter plate 130 to form black spots, and also prevents the hot runner 140a from being blocked.

Referring to fig. 3, 7 and 8, the shape of the mold core 150 is adapted to the shape of the product to mold the product by the mold core 150. The mold core 150 may include a molding portion 151 and a fixing portion 153, the fixing portion 153 is assembled to the rear mold 114, the molding portion 151 is received in the cavity 10a, and the shape of the molding portion 151 is adapted to the shape of the product. In one or more embodiments, the core 150 is detachably fitted at the first penetration hole 114b so that the core 150 can be replaced to accommodate different product shapes by replacing the core 150.

A chute 150a is arranged in the mold core 150, and at least part of the small slide shovel 170 is accommodated in the chute 150a and can slide in the chute 150a under the driving of external force. The mold core 150 is further provided with a through hole 150b, the through hole 150b penetrates through the mold core 150 in the thickness direction, the chute 150a is communicated with the cavity 10a through the through hole 150b, and the small slide block 160 is assembled in the through hole 150b and is connected to the small slide shovel 170 in a sliding manner.

For example, the small-row shovel 170 is provided with a slide 171, and the small-row slider 160 is at least partially embedded in the slide 171, so as to be in sliding fit with the small-row shovel 170. When the small slide shoveling machine 170 slides in the sliding groove 150a, due to the constraint of the sliding rail 171 on the small slide 160 and the limitation of the small slide 160 at the through hole 150b, when the small slide 160 slides along the sliding rail 171, the small slide shoveling machine 170 provides a driving force to the small slide 160 to drive the small slide 160 to move in the through hole 150b so as to move relative to the mold core 150.

For example, the moving direction of the small-row shovel 170 is defined as a first direction X, and the length direction of the slide rail 171 is inclined with respect to the first direction X, so that when the small-row slider 160 slides in the slide rail 171, the small-row slider 160 can be driven to move. In one or more embodiments, both ends of the slide 171 extend completely through the small-row shovel 170, such that the small-row slider 160 can slide in or out from both ends of the slide 171, i.e., the small-row slider 160 can be completely disengaged from the small-row shovel 170.

In the embodiment shown in fig. 7, two small slide blocks 160 are provided, and the through holes 150b and the slide rails 171 are disposed correspondingly to the small slide blocks 160. It can be understood that, in order to realize the opposite movement of the two small slide blocks 160, the two sliding grooves 150a may be symmetrically arranged about a straight line, so that the small slide shoveling machine 170 realizes the equal driving of the two small slide blocks 160.

For example, the small-row slider 160 may include a hook (not shown) that is at least partially embedded in the slide 171 to achieve a sliding fit between the small-row slider 160 and the small-row shovel 170.

Through assembling the small slide block 160 on the mold core 150, in the process of injecting the glue, the small slide block 160 is assembled at the through hole 150b and clamped on the small slide shovel 170, so that the mold cavity 10a is relatively closed to the outside, and the injection molding can be completed under a relatively small pressure. Meanwhile, under a smaller injection pressure, the PCTG material has a slow flowing speed, so that the gas in the cavity 10a can be smoothly discharged, and gas veins of the product caused by unsmooth exhaust are avoided; and the phenomena of cloak, glue shortage and the like of the formed product caused by glue leakage are prevented, and the appearance delicacy of the product and the yield of the product are improved. When the small slide shovel machine 170 is drawn out, the small slide slider 160 moves relative to the mold core 150, so that the injection product can be taken down more easily, and the problem is solved due to the fact that the injection product made of the PCTG material is good in viscosity and not easy to demold, and the small slide slider 160 is arranged, so that the needle valve type hot runner structure 10 can be competent for the injection product made of the PCTG material.

Referring to fig. 1 to 4, in one or more embodiments, a piston 191 may be further included, and the valve needle 120 is fixedly connected to the piston 191 to drive the movement of the valve needle 120 through the piston 191, so that the valve needle 120 is lifted or lowered. And a valve needle positioning block 193 is further included, the valve needle positioning block 193 is arranged corresponding to the piston 191 and is used for positioning the piston 191, when the piston 191 moves to the valve needle positioning block 193, the valve needle 120 cannot fall down continuously, and the positioning of the valve needle 120 is realized.

Referring to fig. 1 to 4, in one or more embodiments, a push block 195 may be further included, a second through hole 114c may be further disposed on the rear mold 114, and the push block 195 is assembled in the second through hole 114c and movably connected to the rear mold 114. The push block 195 serves to push the injection product out of the cavity 10a after the injection product is cooled. In the embodiment shown in fig. 2, two pushing blocks 195 are provided, the two pushing blocks 195 are disposed opposite to each other, and the molded injection product is clamped between the two pushing blocks 195, so that when the pushing blocks 195 move relative to the rear mold 114, the injection product is driven to move relative to the rear mold 114, and the injection product is separated from the cavity 10 a. It will be appreciated that the front mold 112 and the rear mold 114 need to be released before the injection molded product is released from the cavity 10 a.

When the needle valve type hot runner structure 10 is used, first, the PCTG material is heated by the heater to be melted, and the valve needle 120 is heated, so that the PCTG material remaining in the gate 180a is melted after the valve needle 120 is heated, the valve needle 120 is lifted by the driving piston 191, the flow passage 140a is opened, and the PCTG material in a molten state flows through the glue dividing passage of the flow dividing plate 130 and the flow passage 140a of the nozzle head 140 in this order, directly enters the injection hole 112c through the gate 180a, and flows into the cavity 10a along the injection hole 112 c. Because low-pressure injection molding is adopted, the runner 140a is directly communicated with the cavity 10a by aligning the valve needle guide sleeve 180 with the injection molding hole 112c, PCTG material is slowly injected into the cavity 10a, after the cavity 10a is filled, the valve needle 120 falls down by the driving piston 191, when the valve needle 120 enters the runner 140a and the water gap 180a, the residual PCTG material forms a film between the valve needle 120 and the valve needle guide sleeve 180, the film and the valve needle 120 prevent the PCTG material from flowing out together, and the purpose of preventing glue leakage is achieved, and meanwhile, due to the arrangement of the water gap 180a, the PCTG material cannot be remained in the nozzle head 140. And after the injection product is cooled, the small slide shoveling machine 170 is drawn out, the small slide shoveling machine 170 slides relative to the mold core 150 and drives the small slide block 160 to move until the small slide block is completely retracted into the mold core 150. When the small slide block 160 retracts, the small slide block is separated from the injection product, so that the small slide block 160 is prevented from influencing the taking-out of the injection product. Then, the front mold 112 and the rear mold 114 are separated, and the pusher block 195 is pushed to take out the injection molded product.

In the needle valve type hot runner structure 10, the two small slide blocks 160 are added at the mold core 150, and the small slide blocks 160 are firmly clamped on the small slide shovel 170 to form a closed cavity 10a in the glue injection process, so that the product can be fully injected under a small pressure.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. The needle valve type hot runner structure is characterized by comprising a front mold, a rear mold, a valve needle, a flow distribution plate, a nozzle head, a mold core, a small-slide sliding block and a small-slide shovel machine, wherein the small-slide shovel machine is arranged on the front mold, the rear mold, the valve needle, the flow distribution plate, the nozzle head, the mold core, the small-slide sliding

a glue dividing channel is arranged in the flow dividing plate;

2. The needle valve type hot runner structure according to claim 1, wherein a first through hole is provided at an end of the rear mold remote from the front mold, and the core is detachably fitted at the first through hole.

3. The needle valve type hot runner structure according to claim 1, wherein a sliding groove is formed in the mold core, and the small slide shovel machine is at least partially accommodated in the sliding groove and can slide in the sliding groove under the driving of an external force;

4. The needle valve type hot runner structure according to claim 3, wherein a slide way is arranged on the small slide shovel machine, and the small slide block is at least partially embedded into the slide way and is in sliding fit with the small slide shovel machine; when the small slide shoveling machine slides in the sliding groove, the small slide shoveling machine drives the small slide block to move in the through hole.

5. The needle valve hot runner structure according to claim 4, wherein the direction in which the small slide shovel moves is defined as a first direction, and the length direction of the runner is inclined with respect to the first direction.

6. The needle valve hot runner structure according to claim 1, wherein a needle guide is disposed at an end of the nozzle tip remote from the splitter plate and located at a distal end of the flow channel, a nozzle opening is disposed in the needle guide, the nozzle opening communicates with the flow channel, and the needle passes through the splitter plate and the nozzle tip and enters the nozzle opening.

7. The needle valve hot runner structure according to claim 6, wherein a maximum width of the nozzle is greater than a width of the flow channel.

8. The needle valve type hot runner structure according to claim 6, wherein an injection groove is formed on an end surface of the front mold away from the rear mold, an injection hole is formed in a bottom portion of the injection groove, the injection groove communicates with the cavity through the injection hole, and the nozzle head is at least partially received in the injection groove.

9. The needle valve hot runner structure of claim 8, wherein the valve needle guide sleeve is disposed against an end of the injection molding hole such that the flow channel of the nozzle tip is in direct communication with the mold cavity.

10. The needle valve type hot runner structure according to claim 1, further comprising a push block, wherein the rear mold is further provided with a second through hole, and the push block is assembled in the second through hole and movably connected to the rear mold; the pushing block is used for pushing the injection product to be separated from the cavity after the injection product is cooled.