CN102029690A

CN102029690A - Hot nozzle sprue bush

Info

Publication number: CN102029690A
Application number: CN2010105275089A
Authority: CN
Inventors: 徐娜
Original assignee: Shenzhen Skyworth RGB Electronics Co Ltd
Current assignee: Shenzhen Skyworth RGB Electronics Co Ltd
Priority date: 2010-10-29
Filing date: 2010-10-29
Publication date: 2011-04-27

Abstract

The invention discloses a hot nozzle sprue bush for the front end of the hot nozzle of a mould, comprising a sprue bush body (3), screw threads (12) and a sprue, wherein the screw threads (12) are arranged at the excircle of the upper end of the sprue bush body; the sprue is arranged at the inner circle of the lower end of the sprue bush body; the excircle of the lower end of the sprue bush body is a sharp corner(9); the conical degree (2) of the sprue is 8 DEG-10 DEG; and the exit of the sprue is a round corner(8). In the invention, technique means such as the conical degree of the inner wall of the sprue is increased; special polishing treatment is carried out from top to bottom along the conical degree of the sprue; the traditional sharp corner of the exit of the sprue is made to the round corner and the like are adopted to ensure that under the circumstance that the injection molding temperature is constant, the sprue stock column is easy to separate without adhering to the sprue after cooled, and a problem that the plastic stock column is easy to break is solved, thus the production cost is reduced by 50%.

Description

A kind of hot mouth sprue bush

Technical field

The present invention relates to the hot runner mould of injection mo(u)lding, relate in particular to a kind of sprue bush that is used for mold hot mouth leading section.

Background technology

In injection mo(u)lding hot flow path The Application of Technology, TOP-TIP is broadly divided into three classes according to the difference of type: cusp formula TOP-TIP, open TOP-TIP and needle valve TOP-TIP.Its TOP-TIP of every type all has its important use characteristic and the scope of application.Sort out the hot mouth structure that this TOP-TIP of three types can be classified as the band sprue bush from the cast gate pattern.The hot mouth structure of described band sprue bush: instant heating mouth fore-end carries a sprue bush, refills to be fitted on the mold integral.TOP-TIP as needle valve; owing to be provided with sprue bush, its needle just can directly not contact with the cast gate of mould, and the injection moulding sizing material is to have acidity or corrosive a bit; then this sprue bush just can effectively be protected the needle and the gate portions of mould, so that increase the service life of mould.

She Ji hot mouth cast gate routinely occurs usually in practical application: cast gate wire drawing, product cast gate stock column break at heat in the mouth, problem such as difficult taking-ups of mouth of a river material, thereby the progress of influence production causes the increase of production cost.Particularly for quick freezing crystalline plastics, have the transformation of moment sometimes, as long as temperature slightly descends, hard cast gate coagulates material and will produce.And hot mouth front end temperature easily makes cast gate coagulate the material fracture when too low, and the stock column that in hot mouth runner passage, forms, the injection machine that then needs to stop is cleared up, and influences production efficiency greatly.

Summary of the invention

The present invention for cast gate wire drawing, the product cast gate material that solves existing hot mouth cast gate and occur break at heat in the mouth, technical problem such as difficult taking-ups of mouth of a river stock column head, proposes a kind ofly to make that gate freeze is stable, cast gate stock column easy fracture and be convenient to the hot mouth sprue bush that taking-up is expected at the mouth of a river not.

For addressing the above problem, the hot mouth sprue bush that the present invention proposes, comprise the cast gate body, be located at this cast gate body upper end cylindrical screw thread, be located at the cast gate of justifying this cast gate body lower end in, described cast gate body lower end cylindrical is a wedge angle.The tapering of described cast gate is 8 degree～10 degree, and the cast gate exit is a fillet.

Preferred version of the present invention, the tapering of described cast gate can be 8 degree.

Wherein, the radius of curvature of described cast gate fillet is 2mm.

The inwall of described cast gate is the inwall of process along the polishing from top to bottom of its tapering.

The cylindrical of described sprue bush lower end can also be provided with a circle boss.

The height of described boss is 0.5mm.

The invention enables the tapering of cast gate inwall to increase, be more conducive to the stability of gate freeze; Through along the top-down special polishing of cast gate tapering, be convenient to the taking-up of mouth of a river material greatly; The outlet of cast gate is made fillet by original wedge angle, and under the situation of steady temperature, the cast gate stock column breaks away from after supercooling easily, can not stick at cast gate, has solved the difficult problem of plastic cement stock column easy fracture, thereby reduces 50% of production cost.

Description of drawings

The present invention is described further below in conjunction with drawings and Examples, wherein:

Fig. 1 is the cutaway view of preferred embodiment of the present invention;

Fig. 2 uses the schematic diagram of assembling for preferred embodiment of the present invention.

The specific embodiment

Be illustrated in figure 1 as the schematic construction of preferred embodiment of the present invention, described hot mouth sprue bush, comprise cast gate body 3, be located at this cast gate body upper end cylindrical screw thread 12, be located at the cast gate of justifying this cast gate body lower end in, cast gate body 3 lower end cylindricals are wedge angle 9.The tapering 2 of this cast gate is designed to 8 degree～10 degree, and the cast gate exit is a fillet 8.In the present embodiment, the tapering 2 of cast gate is elected the radius of curvature of 8 degree, cast gate fillet 8 as and is elected 2mm as.The inwall of whole cast gate carried out polishing through the polishing personnel of specialty, promptly used thin 600# sand paper along the top-down polishing of tapering, could not be along the circumference polishing! For avoiding the difficult problem of taking out of mouth of a river material, this step is particularly important.The cylindrical of cast gate body 3 lower ends is provided with a circle boss 11, and the radial height of this boss is 0.5mm.Cast gate is the maximal end point of runner in the whole TOP-TIP, also is functional areas crucial in the TOP-TIP, and it has arranged the work of all hot mouths.Because it promptly is the sizing material (plastics short column in the cast gate) of product in process of production and the disengaging between the hot mouth cast gate that the cast gate column cap separates.So the separation of cast gate column cap generally is to occur on the narrowest cross section of gradient cast gate (minimum diameter 6 places).The tapering 2 of cast gate inner chamber is increased to 8 degree～10 degree by 6 original degree, and effectively closed and repeat open effect for the cast gate heating power that keeps hot mouth, all cast gate column caps all will have the size and shape that can bear, and the cast gate aperture generally changes.

As shown in Figure 1 and Figure 2, cast gate body 3 is parts that hot mouth is formed, and its screw thread 12 by top screws in and is assemblied in the body of hot mouth 1, and hot mouth core 10 is housed in the inner chamber of sprue bush top, and needle 5 is housed in the runner of sprue bush.Sprue bush is positioned at the fore-end of hot mouth, constitutes whole hot mouth system.Described hot mouth is seated in 4 li on mould again, hot mouth sprue bush part directly and the mould gate hole closely cooperatively interact.Because the cylindrical of cast gate body 3 lower ends is provided with a circle boss 11, after the assembling, cast gate body 3 roughly just leaves the gap of a circle 0.5mm, formation avoiding hollow groove 7 between cylindrical and the mould gate hole inwall in stage casing.This avoiding hollow groove makes the heat of hot mouth be difficult for passing on the mould, and has effectively reduced the hot transmission loss (cast gate is expected not easy fracture with fixed attention during injection moulding) of hot mouth 1.During injection moulding, the heater by hot flow path adds hot gluse size, and under temperature constant state, the melt of injection moulding sizing material is directed reach in the mold cavity by runner by the nozzle of barrel, at last plastic melt is full of the whole die cavity of mould inside.Gate size can carry out best optimization process according to the regularity of actual injection moulding, regulates cast gate and should carry out the method, and the shape of cast gate should combine with the mold cavity that injects, and can not change the shape of cast gate easily.The type of plastics is depended in the performance of cast gate fracture sometimes, but also with the cast gate design shape close association is arranged.

The present invention adopts the tapering that increases the cast gate inwall, carries out special polishing from top to bottom, again the outlet of cast gate is made technological means such as fillet by original wedge angle along the cast gate tapering, can so that injection temperature under constant situation, the cast gate stock column breaks away from after supercooling easily, can not stick at cast gate, solve the difficult problem of plastic cement stock column easy fracture.Thereby reduce 50% of production cost.

Claims

1. hot mouth sprue bush, comprise cast gate body (3), be located at this cast gate body upper end cylindrical screw thread (12), be located at the cast gate of justifying this cast gate body lower end in, described cast gate body lower end cylindrical is wedge angle (9), it is characterized in that, the tapering of described cast gate (2) is 8 degree～10 degree, and the cast gate exit is fillet (8).

2. hot mouth sprue bush as claimed in claim 1 is characterized in that, the tapering of described cast gate (2) is 8 degree.

3. hot mouth sprue bush as claimed in claim 2 is characterized in that the radius of curvature of described cast gate fillet (8) is 2mm.

4. hot mouth sprue bush as claimed in claim 3 is characterized in that, the inwall of described cast gate is the inwall of process along the polishing from top to bottom of its tapering.

5. hot mouth sprue bush as claimed in claim 4 is characterized in that, the cylindrical of described cast gate body (3) lower end is provided with a circle boss (11).

6. hot mouth sprue bush as claimed in claim 5 is characterized in that the height of described boss (11) is 0.5mm.