CN114108110A

CN114108110A - Melt-blown die

Info

Publication number: CN114108110A
Application number: CN202010899656.7A
Authority: CN
Inventors: 林作钱
Original assignee: ZHEJIANG QIANXIGUANG PLASTIC MOLD CO Ltd
Current assignee: ZHEJIANG QIANXIGUANG PLASTIC MOLD CO Ltd
Priority date: 2020-08-31
Filing date: 2020-08-31
Publication date: 2022-03-01

Abstract

A melt-blowing die head for a melt-blowing machine comprises a die body which is constructed as a base body, a spinneret plate which extends along the longitudinal direction is arranged on the die body, the spinneret plate is constructed with a pair of support plates which are opposite to each other, a protruding structure is arranged in the middle of the support plates, and a plurality of spinneret orifices which are sequentially arranged along the length of the spinneret plate and are used for plastic blowing are constructed at the top end of the protruding structure. The die body is composed of a left side plate and a right side plate which are attached together along the transverse direction and are arranged in a mirror symmetry mode, identical half flow channels are respectively formed in the attached side faces of the left side plate and the right side plate, when the left side plate and the right side plate are attached together, the half flow channels are connected in an opposite mode to form a complete flow channel, the half flow channels comprise multiple equal flow channels formed by a plurality of sub flow channels constructed in a multiple equal mode and upper long groove flow channels constructed in an integrated mode, and the multiple equal flow channels are communicated with the upper long groove flow channels in a fluid mode.

Description

Melt-blown die

Technical Field

The present invention relates to a meltblowing die, in particular for a meltblowing machine for producing meltblown webs. The melt-blown die head is provided with a die body which is constructed as a base body, a spinneret plate extending along the longitudinal direction is arranged on the die body, the spinneret plate is constructed with a pair of support plates which are opposite to each other, a convex structure is arranged in the middle of the support plates, and a plurality of spinneret orifices for plastic spraying are constructed at the top end of the convex structure and are sequentially arranged along the length of the spinneret plate.

Background

The meltblown process is a common textile process in the manufacture of nonwoven fabrics, particularly meltblown fabrics. The spinning method is generally a spinning method which adopts high-speed hot air flow with crossed directions to rapidly stretch, solidify and form a high polymer melt just extruded from a die hole in a high-power mode, and is commonly used for producing non-woven fabrics such as polypropylene fibers, terylene and the like. Its advantages are short technological route, and direct spinning to obtain non-woven fabric.

The melt-blown machine is a core component for manufacturing non-woven fabrics by a melt-blown method, wherein the melt-blown die head is a core component for realizing high polymer wire drawing in the melt-blown machine. The structure of the melt-blowing die head directly influences the length, uniformity, toughness, fineness and the like of drawn wires, thereby having decisive influence on the final melt-blown fabric finished product. In the prior art, the working principle of the traditional investment spray head is as follows: the plastic enters the die body cavity and is heated to melt the plastic, the melted plastic slowly enters the spinneret plate in the form of molten material, air enters from the air inlet pipeline, high-flow-rate air is formed and blown out from the air plate, and the molten material in the spinneret plate is blown out from the spinneret orifice along with high-speed air flow, is further drawn and is provided for the next spinning process.

For example, from document CN108716023A, a meltblowing die for fiber production is known, which comprises a die body, a spinneret and a gas plate, which are detachably mounted in the die body, in which spinneret a spinneret orifice is provided, between which spinneret and gas plate a plurality of slot slots are formed. And a plurality of gas circulation channels are also arranged in the die head main body and are communicated with the crack groove. In addition, be equipped with the return flow channel in the spinneret, when the spinneret takes place to block up, the raw materials can flow into screw extruder again through the return flow channel to unnecessary raw materials loss has been reduced, the risk that too big pressure caused the influence to self structure can be reduced moreover.

In addition, another melt-blowing die head for producing non-woven fabrics is known from document CN205907402U, which includes a spinneret plate, an air plate is disposed on the outer wall of the spinneret plate, a spinneret plate protective cover is mounted at the bottom of the air plate, a base body is disposed on the top of the spinneret plate, a die body cavity is longitudinally disposed in the middle of the outer wall of the base body, and air inlet ducts are disposed on both the left and right sides of the die body cavity. By utilizing the air inlet pipeline arranged on the die body, air is blown out from the air knife after flowing through the die, so that uniform and stable air outlet is kept, the condition of uneven silk outlet is reduced as much as possible, and the silk outlet quality of the die is ensured.

As is known from the prior art, in the case of the known investment nozzles, a single fan-shaped flow channel is usually used, which leads to an uneven distribution of the melt fed into the spinneret, i.e. to a fast central discharge and a slow edge discharge, which in turn leads to an uneven spinning of the spinneret. Because the spinning is uneven and dead angles exist in the spinneret plate, plastics are bonded in the spinneret plate for a long time and can be plasticized, and plasticized hard materials enter the spinneret plate and then block the spinneret plate, are not easy to clean and can affect the product quality for a long time; in addition, the heating of the plastic is not uniform due to the integrally formed mold body, so that the nozzle of the spinneret plate is easily broken due to local high pressure. The prior art only aims to remedy the problems of uneven spinning, uneven heating and blockage of a spinning nozzle, but cannot fundamentally prevent the problems.

Disclosure of Invention

Aiming at the problems of the existing melt-blowing die head, the invention provides an improved fusible pattern nozzle which is provided with a split die body and is constructed with a multiple equal division runner system, runners have no dead angle and are convenient to install and clean, and a spinneret plate of the fusible pattern nozzle is provided with a flow dividing mechanism and a heat conducting mechanism, so that a melt can be uniformly sent into the spinneret plate and then sent to a spinneret orifice to be discharged, and the technical problems of non-uniform spinning, spinneret orifice blockage, non-uniform heating of the melt and the like can be fundamentally solved.

According to the invention, a melt-blowing die head, in particular for melt-blowing machines, is provided with a die body designed as a base body, on which a spinneret extending in the longitudinal direction is arranged, which spinneret is designed with a support plate lying opposite one another, in the middle of which a projection is arranged, at the tip of which a plurality of nozzles for plastic injection are designed, which are arranged one behind the other along the length of the spinneret. According to the invention, the mold body is formed by two left and right side plates which are attached to each other in the transverse direction and are arranged in mirror symmetry with each other, and identical half flow channels are respectively hollowed out on the side surfaces of the left and right side plates which are attached to each other, and when the left and right side plates are attached to each other, the half flow channels are butted to form a complete flow channel, wherein the half flow channels comprise multiple equal flow channels formed by a plurality of sub flow channels constructed in multiple equal parts and upper long groove flow channels constructed in an integrated manner, and the multiple equal flow channels are in fluid communication with the upper long groove flow channels. In practice, the left side plate and the right side plate can be fixed together through threaded fasteners, including but not limited to bolts and screws, to form a die body, according to the technical scheme of the invention, the two side plates respectively containing the half flow channels are butted into a complete die body to form a complete flow channel, so that the flow channel is convenient to disassemble and clean, and further uneven spinning caused by difficulty in cleaning after the flow channel is blocked is avoided.

Preferably, according to the present invention, the upper elongated channel is disposed above the multiple equally divided channels, the multiple equally divided channels have a channel inlet and a plurality of channel outlets uniformly arranged in sequence along the longitudinal direction, wherein the channel outlets are in fluid communication with the upper elongated channel, and the multiple equally divided channels are multiple halved channels, that is, two sub-channels are bifurcated from one channel near the channel inlet, each sub-channel is bifurcated into two sub-channels, and/or two sub-channels are bifurcated into more sub-channels, and each sub-channel finally leads to one channel outlet. The novel use of a multiple-divided flow channel arrangement consisting of a plurality of sub-flow channels allows the polymer melt, preferably plastic melt, used for producing the meltblown fabric to be distributed as uniformly as possible over the entire length of the meltblowing die head, so that it can be fed uniformly into the spinneret and extruded uniformly through the spinneret orifices, without the melt fed into the spinneret being uneven due to the fast intermediate and slow side discharges. In a preferred embodiment according to the invention, the multiple equally divided flow channel is quartered in half with a total of sixteen sub-flow channels. Of course, depending on the actual size and processing requirements of the meltblowing die, configurations such as eight or thirty-two sub-runners and runner outlets or more or fewer sub-runners and runner outlets are possible and fall within the scope of the invention.

According to a further preferred embodiment of the present invention, each of the flow path outlets of the multiple equal flow paths is a slit formed by a tube portion and a wall portion, the slit having a width smaller than the flow path diameter, wherein each of the flow path outlets includes two short sides constituted by the tube portions having a gradually decreasing cross section and the wall portion connecting the two tube portions, and is configured in a hanger shape of an obtuse triangle as a whole. The flow channel outlet constructed in the shape of the clothes rack avoids the phenomenon that plastic melt is accumulated in a dead angle for a long time to be plasticized due to the formation of the dead angle in the flow channel outlet of the multiple equal-divided flow channels, and the plasticized hard material enters a spinneret plate to finally cause the blockage of a spinneret orifice.

According to another preferred embodiment of the invention, a lower elongated channel is centrally cut out in the longitudinal direction on the lower side of the injection-molding plate, and a hollow injection-molding cavity extending in the longitudinal direction is centrally arranged in the injection-molding plate, wherein the injection-molding cavity extends upwards into the projection of the injection-molding plate until it is in fluid communication with the spinneret and the injection-molding cavity extends downwards into the lower elongated channel, wherein the lower elongated channel of the injection-molding plate is in fluid communication with the upper elongated channel of the mold body. The melt is fed from the die body into the spinneret plate by the two elongated channels being in fluid communication with each other.

Further preferably, a branched stream is arranged in a lower long groove flow channel of the injection molding plate, and one or more high heat conducting plates are arranged in the injection molding cavity and extend upwards to the position below the spinning nozzle, wherein the high heat conducting plates are positioned in the middle of the branched stream. The branched beams have a rectangular strip-shaped structure and are embedded in long groove flow channels at the lower part of the plastic spraying plate, wherein a plurality of uniformly distributed through grooves are respectively formed in the branched beams at two sides of the high heat conduction plate, and smooth chamfers are arranged at upper and lower openings of the through grooves. The partial flow bundle can be embodied in two ways, on the one hand, it can be split and has two left and right parts that are mirror-symmetrical to each other, wherein the left and right half parts are respectively located on both sides of the high thermal conductive plate and form the through-groove at the contact with the high thermal conductive plate; on the other hand, the partial streams may also be formed in one piece, wherein a recess is provided in the middle of the partial streams, into which recess the high thermal conductivity plate is inserted and on both sides of which recess the through-grooves are formed.

According to another preferred embodiment of the present invention, a filter screen for filtering the molten material is disposed between the upper elongated channel of the mold body and the lower elongated channel of the plastic-injection plate, and the filter screen is fastened to the plastic-injection plate by a filter screen pressing plate. The arrangement of the filter screen further ensures that harmful substances which can obstruct spinning, such as plasticized hard materials and the like which can enter the spinneret plate, are completely shielded.

Further, a sealing band is provided around the multiple aliquoting flow passages, the sealing band fluidly sealing the multiple aliquoting flow passages with respect to the left and right side plates. Preferably, the sealing band is in fluid-tight connection with the left and right side plates via fastening screws, high temperature split spring washers, or the like. The structural form that the half flow channels in the two side plates are spliced into the complete flow channel is adopted, so that higher requirements are put on the flow channel sealing, and special sealing strips are arranged around the multiple equally-divided flow channels and are fixed together by high-temperature open spring gaskets and the like. When the joint is expanded by heat and contracted by cold, the joint is kept from leaking due to the action of a high-temperature opening spring gasket and the like.

According to a particularly preferred embodiment of the present invention, a hot air adjusting plate extending in the longitudinal direction for blowing out hot air is fastened to each of the support plates, and hot air passage cover plates for the hot air adjusting plates are provided at both ends of the plastic injection plate in the longitudinal direction, respectively, the hot air passage cover plates covering hot air passage holes provided in the hot air adjusting plates, and hot air passages extending in the longitudinal direction and communicating with the hot air passage holes are further provided in the hot air adjusting plates, a plurality of blowing holes are evenly distributed in the hot air passages, and hot air fed from an air inlet of a blower is blown out from the blowing holes of the hot air passages through the hot air passage holes and further into air gaps between the hot air adjusting plates and the projection structures of the plastic injection plate, wherein the width of the air gaps can be adjusted, and the compensation height between the upper surface of the hot air adjusting plate and the top end of the plastic spraying plate can be adjusted. The hot air adjusting plate is arranged, so that the size of hot air flowing through the spinneret orifice can be adjusted, the uniformity of the air flow at the spinneret orifice is kept, and the proper temperature at the spinneret orifice is kept to be increased. In addition, the air gap and the compensation height may be adjusted by adjusting the fastening degree of the die plate to the die body and the fastening degree of the hot air adjusting plate to the die plate, thereby preventing interference between the hot air adjusting plate and the tip end of the die plate.

In addition, the spinneret plate is fixed to the upper surfaces of the left and right side plates of the mold body using threaded fasteners, including but not limited to screws, bolts, etc. Of course, other detachable connection methods for fixing the spinneret plate and the die body are also feasible for the present invention, and all fall into the protection scope of the present invention.

A plurality of heating devices for heating the melt are arranged in the mold body or the left side plate and the right side plate. For example, in a preferred embodiment, two heating devices arranged one above the other are provided in each case in mirror image symmetry with respect to one another in the left and right side of the mold body. Through setting up heating device and based on the high heat conductivity of the high heat-conducting plate that sets up for get into the plastic-blasting cavity plastic and keep a constant temperature, thereby can be smoothly extruded by the spinneret, reduced pressure, avoided causing the fracture of spinneret because of the high pressure.

Drawings

The following detailed description of the preferred embodiments of the present invention is provided in conjunction with the accompanying drawings, and the following description is exemplary and not limiting, and any other similar cases are within the scope of the present invention. In the following detailed description, directional terms, such as "left", "right", "upper", "lower", "front", "rear", and the like, are used with reference to the orientation as illustrated in the drawings. Components of embodiments of the present invention can be positioned in a number of different orientations and the directional terminology is used for purposes of illustration and is in no way limiting. In particular, the "longitudinal direction" in the present invention refers to a direction extending along the length of the investment spray head; the "transverse direction" refers to a direction extending along the width of the investment spray head. Wherein the various figures respectively show:

FIG. 1 is a schematic perspective view of a meltblowing die for a meltblowing machine according to the invention;

FIG. 2 is a cross-sectional top view of the meltblowing die shown in FIG. 1 taken at the spinneret;

FIG. 3 is a cross-sectional view of a meltblowing die according to the invention taken along section line A-A shown in FIG. 2;

FIG. 4 is an enlarged view of the cut out section I shown in FIG. 3;

FIG. 5 is a cross-sectional view of a meltblowing die according to the invention taken along section line B-B shown in FIG. 2;

FIG. 6 is an enlarged view of section II of FIG. 5;

FIG. 7a is a sectioned diagrammatic perspective view of a spinneret plate of a meltblowing die according to the invention;

FIG. 7b is a cut-away section of a schematic perspective view of the underside of the spinneret plate of a meltblowing die according to the invention;

FIG. 8 is a sectioned-out section of a schematic perspective view of one of the hot air adjustment plates of a meltblowing die according to the invention;

fig. 9 is a further enlarged view of the cut-out section III shown in fig. 6.

Detailed Description

Fig. 1 schematically shows a perspective view of a meltblowing die 1 for a meltblowing machine according to the invention, in which the overall structure of the meltblowing die 1 is shown. The meltblowing die 1 has a die body 20 as a base body, and the die body 20 is formed by two left and

right side plates

21 and 22 which are abutted against each other in the transverse direction. A plurality of through holes or blind holes 25 for receiving threaded fasteners are provided on the sides of the left and

right side plates

21, 22, and the left and

right side plates

21, 22 can be detachably connected by threaded fasteners such as screws (see fig. 4 for details). A spinneret 10 extending in the longitudinal direction is further disposed on the die body 20, and a pair of hot

air adjusting plates

31 and 32 extending in the longitudinal direction and used for blowing out hot air are fixed to the spinneret 10. In addition, a hot

air duct cover

41, 42 covers the spinneret plate 10 and the hot

air adjusting plates

31, 32 at both ends in the longitudinal direction.

Fig. 2 is a cross-sectional top view of the meltblowing die 1 shown in fig. 1 taken at the spinneret 10. In this figure, a section line that cuts the meltblowing die 1 from the middle of the meltblowing die in the transverse direction is denoted by a-a, and a section line that cuts the meltblowing die 1 from the middle of the meltblowing die in the longitudinal direction is denoted by B-B. As shown in fig. 2,

support plates

11 and 12 are provided at both ends of the spinneret plate 10 in the transverse direction, respectively, so as to face each other, and the spinneret plate 10 can be detachably attached to the left and

right side plates

21 and 22 by screw fasteners received in screw holes 26. Furthermore, a lower slot channel 15 is provided in the middle of the spinneret plate 10 in the transverse direction, and a partial flow bundle 13 for dividing the incoming melt is arranged in the lower slot channel, said partial flow bundle 13 clamping the high thermal conductive plate 5 in the middle. The length of the lower elongated slot flow channel 15, the split beam 13 and the high heat conducting plate 5 is slightly smaller than the length of the spinneret plate 10 and does not extend to the edge of the spinneret plate, so as to ensure the necessary strength of the spinneret plate 10.

FIG. 3 shows a cross-sectional view of a meltblowing die 1 according to the invention taken along the section line A-A shown in FIG. 2. The specific structure of one of the left side plate 21 and the right side plate 22 can be seen from fig. 3, and the structure of the other of the left side plate 21 and the right side plate 22 is completely mirror-symmetrical to that shown in fig. 3, so that the left side plate 21 and the right side plate 22 can be combined into a complete mold 20. For example, in the left side plate 21, half channels 27 are cut out on the side facing the right side plate, and the half channels 27 and the half channels cut out on the right side plate 22, which are mirror images of each other, can be joined to form a complete channel.

As shown in fig. 3, the half flow channel 27 includes a multiple-divided flow channel 29 formed of a plurality of sub flow channels 30 configured in multiple-divided form and an upper long groove flow channel 28 configured integrally. The upper elongated slot flow channel 28 is arranged above the multiple aliquoting flow channel 29, and the multiple aliquoting flow channel 29 is in fluid communication with the upper elongated slot flow channel 28. The multiple equally dividing flow channel 29 has a flow channel inlet 33 and a plurality of flow channel outlets 34 which are arranged in sequence and uniformly along the longitudinal direction after multiple equal dividing, wherein the flow channel outlets 34 are in fluid communication with the upper long groove flow channel 28. In the embodiment shown in fig. 3, the multiple equal-dividing flow channel 29 is a multiple halving flow channel, that is, two sub-flow channels are branched from one flow channel near the flow channel inlet 33, each sub-flow channel is further branched into two sub-flow channels, further two sub-flow channels are further branched into two sub-flow channels, and therefore the sub-flow channels are further branched into sixteen sub-flow channels, and each sub-flow channel 30 is finally led to one flow channel outlet 34. Of course, it is also possible to finally branch into more or fewer sub-runners, for example eight or thirty-two sub-runners, etc., depending on the size of the meltblowing die and the actual requirements. This multiple-split flow channel configuration allows melt fed into the die body 20 of the meltblowing die from the flow channel inlet 33 to be uniformly distributed throughout the length of the die body 20 for subsequent uniform delivery to the spinneret 10.

The enlarged view of fig. 4 with respect to section I of fig. 3 shows a schematic structure of the flow channel outlet. This is a particularly preferred embodiment, wherein each flow channel outlet 34 of the multiple-divided flow channel 29 is a slit formed by a tube portion and a wall portion, the slit having a width smaller than the flow channel diameter, wherein each flow channel outlet 34 comprises two short sides constituted by tube portions having gradually decreasing cross sections and a wall portion connecting the two tubes, and is configured in a coat hanger shape of an obtuse triangle as a whole. Such slits having a coat hanger shaped wall portion replace the melt outlet apertures such that melt exiting each channel outlet is not only dispensed centrally from a single aperture but rather is more uniformly linearly delivered to the upper elongated channel 28 along the entire length of the slit. Of course, it is also possible to construct the channel outlet 34 with other wall portions of similar shapes for the present invention, for example, the channel outlet may be formed by the tube outlet of each sub-channel, and when there are enough sub-channels, the channel outlet extends over the upper long channel 28, and the molten material can be delivered uniformly enough, and the above technical solution also falls into the protection scope of the present invention.

Furthermore, as can be seen from fig. 3, a sealing band 35 is provided around the multiple aliquoting flow channel 29, which sealing band 35 is capable of fluid sealing the multiple aliquoting flow channel 29 with respect to the left and

right side plates

21, 22 via a high temperature open spring gasket 36 (see fig. 4).

FIG. 5 shows a cross-sectional view of a meltblowing die 1 according to the invention taken along section line B-B shown in FIG. 2. In addition to the meltblowing die 1, a housing 2 covering the meltblowing die 1 and a blowing machine 3 for blowing air to the meltblowing die 1 are shown, and the blowing machine 3 supplies hot air to the hot

air adjusting plates

31, 32 through an air inlet 4, respectively.

From fig. 5 it is clear that the left and

right side panels

21, 22, which lie against each other in the transverse direction, are independent of each other and mirror-symmetrical. The left and

right side plates

21 and 22 are connected to each other at inner side surfaces opposite to each other by screw fasteners received in the screw holes 25, and thus can be very conveniently disassembled into two separate parts, so that the respective flow passages can be very easily cleaned. In the illustrated embodiment, the threaded holes in the left side plate 21 are blind holes, the threaded holes in the right side plate 22 are through holes, and a high temperature split spring washer 36 is provided in the threaded holes to provide lock compensation. Of course, it is also possible for the invention to provide other elements with similar lock compensation functions, all falling within the scope of the invention. Furthermore, a plurality of heating devices 37 for heating the plastic material are provided in the mold body 20, and in the embodiment shown in fig. 4, two heating devices 37 arranged one above the other are provided in each case in mirror image symmetry with respect to one another in the left side plate 21 and the right side plate 22 of the mold body 11.

As further shown in fig. 5, the injection plate 10 is configured with a pair of

support plates

11, 12 opposite to each other, a protrusion structure 8 is disposed between the

support plates

11, 12, and a plurality of nozzles 14 for injection molding are sequentially arranged along the length of the injection plate 10 at the top end 9 of the protrusion structure 8, in the embodiment shown here, the protrusion structure 8 is configured as a triangle, although other similar shapes with a pointed end are also possible for the protrusion structure, and fall within the protection scope of the present invention. In this case, a hot

air adjusting plate

31, 32 extending in the longitudinal direction for blowing out hot air is fastened to each of the

support plates

11, 12, the left and

right side plates

21, 22 are each formed with a

baffle plate

23, 24 on the outer side facing away from each other, the spinneret plate 10 is arranged overall between the

baffle plates

23, 24, as described above, the spinneret plate 10 can be fastened to the left and

right side plates

21, 22 by means of threaded fasteners, and the hot

air adjusting plates

31, 32 can be fastened to the two

support plates

11, 12 of the spinneret plate 10 by means of threaded fasteners.

As can also be seen from fig. 5, a lower slot channel 15 is centrally cut in the longitudinal direction on the underside of the spinneret plate 10, and a hollow plastic injection cavity 18 extending in the longitudinal direction is centrally provided in the interior of the spinneret plate 10, wherein the plastic injection cavity 18 projects upward into the projection 8 of the spinneret plate 10 and is in fluid communication with the spinning orifices 14, and the plastic injection cavity 18 opens downward into the lower slot channel 15, wherein the lower slot channel 15 of the spinneret plate 10 is in fluid communication with the upper slot channel 28 of the mold body 20.

The detail of the design of the spinning plate 10, in particular after the partial stream 13 and the high thermal conductivity plate 5 have been introduced into the spinning plate 10, can be seen from the enlarged partial illustration of the spinning plate 10 shown in fig. 6 and from the cut-out sections of the perspective views of the spinning plate 10 shown in fig. 7a to 7 b.

As can be seen more clearly in fig. 6 and 7a to 7b, a plurality of orifices 14 for plastic injection are formed at the top end 9 of the raised structure 8 of the spinneret 10, which are arranged in succession along the length of the spinneret 10, a lower slot channel 15 is centrally formed in the lower side of the spinneret 10 in the longitudinal direction, and a hollow plastic injection cavity 18 extending in the longitudinal direction is centrally formed in the interior of the spinneret 10, wherein the plastic injection cavity 18 extends upward into the raised structure 8 of the spinneret 10 and is in fluid communication with the orifices 14, and the plastic injection cavity 18 opens downward into the lower slot channel 15, wherein the lower slot channel 15 of the spinneret 10 is in fluid communication with the upper slot channel 28 of the die body 20. The melt fed into the die body 20 then enters the spinneret plate 10 via the multiple-divided channels in the die body 20, the upper elongated channel 28 and further via the lower elongated channel 15. A branched stream 13 is arranged in a lower elongated channel 15 of the spinneret 10, and a high thermal conductive plate 5 is arranged in the plastic injection cavity 18, wherein the high thermal conductive plate 5 is located in the middle of the branched stream 13, the high thermal conductive plate 5 extends upward to below the spinneret orifice 14, wherein the branched stream 13 has a rectangular strip-shaped structure and is embedded in the lower elongated channel 15 of the spinneret 10, wherein the branched stream 13 is configured with a plurality of uniformly distributed through grooves 19 near the high thermal conductive plate 5, and the branching effect is achieved through the through grooves 19, so that the molten material fed into the spinneret 10 can be more uniformly fed into the plastic injection cavity 18. In addition, smooth chamfers are arranged at the upper opening and the lower opening of the through groove 19, so that a channel without flow resistance and dead angles is formed in the space of the long groove flow channel 15 at the lower part and the lower part of the high heat conducting plate 5, and the phenomenon that the spinning nozzle 14 is blocked by hard materials formed by plasticizing the molten materials at high temperature for a long time due to flow resistance and dead angles is avoided. In the embodiment shown in fig. 6, the branched bundle 13 is composed of left and right halves, wherein the left and right halves are located on both sides of the high thermal conductive plate and the through groove 19 is formed at a contact point with the high thermal conductive plate. According to the length of the die body, a plurality of high heat conducting plates can be arranged in sequence along the longitudinal direction of the die body. The introduction of the high heat conducting plate leads the high-temperature melt to be quickly and effectively guided to the spinneret orifice, and greatly improves the heating effect and the melt-blowing effect.

As shown in fig. 6, a filter screen 16 for filtering the melt is disposed between the upper elongated channel 28 of the die body 20 and the lower elongated channel 15 of the spinneret plate 10, and the filter screen 16 is fastened to the spinneret plate 10 by a filter screen press plate 17. As can also be seen from fig. 5, the mold body 20 is provided with heating devices 37 arranged in mirror symmetry for heating the melt, and the melt flowing through the entire melt-blowing mold head 1 is uniformly heated by the heating devices 37 and the high thermal conductive plate 5 arranged in the plastic-blowing cavity 18, so that the melt to be ejected is kept at a constant temperature and can smoothly flow out in parallel under pressure from the spinneret orifices, thereby reducing the pressure and eliminating the risk of spinneret orifice rupture caused by high pressure.

Fig. 7a and 7b show sections of the spinneret plate 10 in a top and bottom perspective view, respectively, in order to clearly show the structure of the spinneret plate 10. As shown in fig. 7a,

support plates

11, 12 are provided at both ends of the spinneret plate 10 in the longitudinal direction, and a protruding tip 9 is formed at the center in the longitudinal direction, threaded holes are provided in the bottom wall between the tip 9 and the

support plates

11, 12, through which fasteners can fasten the spinneret plate to the left and

right side plates

21, 22 of the mold body 20, and threaded holes are formed in the

support plates

11, 12 for receiving fasteners fastening the hot

air adjusting plates

31, 32 to the spinneret plate 10.

Fig. 8 shows a cut-out section of a schematic perspective view of one of the hot

air adjusting plates

31 or 32 of the meltblowing die according to the invention. The internal structure of the hot air adjusting plate can be seen from fig. 8, and the hot

air adjusting plates

31 and 32 are configured as long strips having a trapezoidal cross section, and the trapezoidal cross section of the hot

air adjusting plates

31 and 32 matches the shape of the top end 9 of the spinneret plate 10 and the side surfaces of the

support plates

11 and 12, but other shapes may be used as long as the shapes match each other. The hot air channel holes 39 penetrate through the whole hot

air adjusting plates

31 and 32 along the transverse direction, rectangular hot air channels 40 are drawn on the lower surfaces of the hot

air adjusting plates

31 and 32, the length of each hot air channel 40 is slightly shorter than that of each hot

air adjusting plate

31 and 32, and a plurality of air blowing holes 38 are uniformly distributed in the hot air channels 40 along the longitudinal direction.

Fig. 9 shows a further enlarged view of the view of fig. 6 in the vicinity of the tip end 9 of the spinneret 10 in an embodiment of the further enlarged view of the tip end 9 of the raised structure 8 of the spinneret 10. As shown in fig. 9, an air gap 6 exists between the side 6 of the hot

air adjusting plates

31, 32 from which hot air is blown and the tip end 9 of the spinneret 10, and a compensation height 7 exists between the upper surfaces of the hot

air adjusting plates

31, 32 and the tip end 9 of the spinneret 10. Referring to fig. 5, 6 and 8, hot air flow is blown from the air blower 3 into the hot

air adjusting plates

31, 32 through the air inlet passages 4 and finally blown from the blowing holes 38 into the hot air passage 40 via the hot air passage holes 39, and then flows out from both sides of the spinneret orifices 14 via the air gaps 6 between the hot

air adjusting plates

31, 32 and the tips 9 of the convex structures 8 of the spinneret plate 10. By adjusting the hot

air adjusting plates

31 and 32, the size of the hot air flow flowing out of the hot air passage 40 can be adjusted, so that the air supply flowing through the spinneret 14 is uniform, and the temperature of the spinneret 14 is increased.

In addition to adjusting the blowing power of blower 3, the magnitude of the hot air flow flowing out of hot

air adjusting plates

31, 32 can also be adjusted by adjusting the above air gap 6 and compensation height 7. The air gap 6 and the compensation height 7 can be adjusted, for example, by adjusting the fastening degree and the fastening position of the hot

air adjusting plates

31, 32 on the spinneret plate 10, which can be achieved by fixing the hot

air adjusting plates

31, 32 to the spinneret plate using stroke-adjustable fasteners and by providing spacers between the hot

air adjusting plates

31, 32 and the spinneret plate 10, although other technical means capable of changing the gap between the objects are also conceivable in the mechanical field. Furthermore, interference between the hot

air adjusting plates

31, 32 and the tip end 9 of the spinneret plate 10 can be avoided by adjusting the air gap 6 and the compensation height 7.

The best mode of carrying out the invention is described in detail above with reference to the accompanying drawings. It should be understood by those skilled in the art that the drawings and their corresponding descriptions are merely for purposes of illustrating the invention and that other modifications, substitutions and alterations may be made by those skilled in the art based on the teachings herein. Such modifications, substitutions or improvements are intended to be within the scope of the invention.

List of reference numerals:

1 melt blowing die

2 housing

3 air blower

4 air inlet channel of air blower

5 high heat-conducting plate

6 air gap

7 compensating for height

8 raised structure of spinneret plate

9 top end of the convex structure

10 spinneret plate

11 support plate of spinneret plate

12 support plate of spinneret plate

13 split beam

14 spinning nozzle

15 lower long groove flow passage

16 filter screen

17 filter screen pressure plate

18 spraying plastic cavity

19 through groove

20 die body

21 left side plate

22 right side plate

23 stop surface of left side plate

24 stop surface of right side plate

25 threaded holes in the left and right side plates

26 threaded hole on spinneret plate

27 half runner

28 Upper long groove flow passage

29 multiple equal dividing flow passage

30 sub-channels

31 hot air adjusting plate

32 hot air adjusting plate

33 channel inlet

34 outlet of flow passage

35 sealing tape

36 high-temperature opening spring gasket

37 heating device

38 air blowing hole

39 hot air passage hole

40 hot air channel

41 hot air channel cover plate

42 hot air channel cover plate.

Claims

1. A melt-blowing die head (1) for a melt-blowing machine, having a die body (20) designed as a base body, on which die body (20) a spinning plate (10) extending in the longitudinal direction is arranged, wherein the spinning plate (10) is designed with a pair of support plates (11, 12) lying opposite one another, wherein a projection (8) is arranged between the support plates (11, 12), wherein a plurality of spinning orifices (14) for plastic blowing are designed at the tip (9) of the projection (8) in a sequential manner along the length of the spinning plate (10),

the die body (20) is characterized by comprising a left side plate (21) and a right side plate (22) which are attached together along the transverse direction and are arranged in a mirror symmetry mode, identical half flow passages (27) are respectively formed in the attached side faces of the left side plate (21) and the right side plate (22) in a digging mode, when the left side plate (21) and the right side plate (22) are attached together, the half flow passages (27) are butted to form a complete flow passage, wherein the half flow passages (27) comprise multiple equally-divided flow passages (29) formed by a plurality of sub flow passages (30) which are constructed in a multiple equally-divided mode and upper long groove flow passages (28) which are integrally constructed, and the multiple equally-divided flow passages (29) are in fluid communication with the upper long groove flow passages (28).

2. The meltblowing die (1) according to claim 1, characterized in that the upper elongated slot flow channel (28) is arranged above the multiple aliquoting channels (29), the multiple aliquoting channels (29) having a channel inlet (33) and a plurality of channel outlets (34) arranged uniformly in succession in the longitudinal direction, wherein the channel outlets (34) are in fluid communication with the upper elongated slot flow channel (28).

3. Meltblown die head (1) according to claim 2, characterised in that the multiple flow channel (29) is a multiple flow channel bisecting from one channel into two sub-channels (30) in the vicinity of the channel inlet (33), each sub-channel continuing bifurcating into two sub-channels (30) and/or continuing into two sub-channels (30), each sub-channel (30) finally leading to a channel outlet (34).

4. Meltblown die (1) according to claim 2, characterised in that the individual channel outlet (34) of the multiple partial channel (29) is a slit formed by a tube section and a wall section, the width of the slit being smaller than the channel diameter, wherein the individual channel outlet (34) comprises two short sides consisting of tube sections of decreasing cross-section and a wall section connecting the two tube sections and is constructed overall in the shape of an obtuse-angled triangle.

5. Meltblown die head (1) according to any of claims 1 to 4, characterised in that a lower slot (15) is centrally hollowed out in the longitudinal direction on the underside of the spinneret (10), and a hollow plastic injection cavity (18) extending in the longitudinal direction is centrally provided in the interior of the spinneret (10), wherein the plastic injection cavity (18) extends up into the projection (8) of the spinneret (10) up to the spinning orifices (14) and the plastic injection cavity (18) opens down into the lower slot (15), wherein the lower slot (15) of the spinneret (10) is in fluid communication with the upper slot (28) of the die body (20).

6. Meltblown die head (1) according to claim 5, characterised in that a partial stream (13) is arranged in the lower elongated channel (15) of the spinneret (10) and in that one or more highly thermally conductive plates (5) are arranged in the spray cavity (18), said highly thermally conductive plates (5) extending up to below the spinning orifices (14), wherein the highly thermally conductive plates (5) are located in the middle of the partial stream (13).

7. Melt-blowing die head (1) according to claim 6, characterised in that the partial stream (13) has a rectangular strip-like structure which engages in the lower long channel flow (15) of the spinneret (10), wherein the partial stream (13) is formed with a plurality of uniformly distributed through-channels (19) close to the high thermal conductivity plate (5), wherein smooth chamfers are provided at the upper and lower openings of the through-channels (19).

8. Meltblown die head (1) according to claim 5, characterised in that a filter screen (16) for filtering the melt is arranged between the upper slot (28) of the die body (20) and the lower slot (15) of the spinneret (10), the filter screen (16) being fastened to the spinneret (10) by means of a filter screen pressure plate (17).

9. Meltblown die head (1) according to any of claims 1 to 4, characterized in that a sealing band (35) is provided around the multiple aliquoting channels (29), said sealing band (35) fluidly sealing the multiple aliquoting channels (29) from the left and right side plates (21, 22) via a high temperature open spring gasket (36).

10. The melt blowing die head (1) according to any one of claims 1 to 4, characterized in that a hot air adjusting plate (31, 32) extending in the longitudinal direction for blowing out hot air is fastened to each of the support plates (11, 12), and a hot air passage cover plate (41, 42) for the hot air adjusting plate (31, 32) is provided at each of both ends of the spinneret plate (10) in the longitudinal direction, the hot air passage cover plate (41, 42) covering a hot air passage hole (39) provided in the hot air adjusting plate (31, 32), and a hot air passage (40) extending in the longitudinal direction and communicating with the hot air passage hole (39) is further provided in the hot air adjusting plate (31, 32), a plurality of blowing holes (38) are uniformly provided in the hot air passage (40), and hot air fed by an air inlet (4) of a blowing machine (3) is blown from the hot air passage (40) through the hot air passage hole (39) Air holes (39) are blown out and blown into an air gap (6) between the hot air adjusting plate (31, 32) and the raised structure (8) of the spinneret plate (10), wherein the width of the air gap (6) can be adjusted and the compensation height (7) between the upper surface (38) of the hot air adjusting plate (31, 32) and the tip (9) of the spinneret plate (10) can also be adjusted.