CN117325401A

CN117325401A - Single-head needle valve capable of rapidly changing color and preparation method thereof

Info

Publication number: CN117325401A
Application number: CN202311262801.0A
Authority: CN
Inventors: 董钟铭; 屈琴; 王艳云
Original assignee: Shenzhen Mould Tip Technology Co ltd
Current assignee: Shenzhen Mould Tip Technology Co ltd
Priority date: 2023-09-27
Filing date: 2023-09-27
Publication date: 2024-01-02

Abstract

The utility model relates to a but single-end needle valve of quick colour change and preparation method thereof, single-end needle valve includes cylinder device and valve body device, the valve body device is including chewing the first, the main part is chewed to the purt and chew the body according to the purt of glue flow direction mutual rigid coupling in proper order, the purt is chewed first and is chewed the main part and locate cylinder device inside, the center that the purt chews the first has seted up into the mouth of gluing, two branch flow ways with advance the mouth intercommunication are chewed to the purt in the main part, one with the equal sprue that communicates of every branch flow way has been seted up in the mouth body, the main part of every branch flow way is the arcuation, the method of seting up of branch flow way is that a purt is chewed the main part by two and is half branch flow ways of arcuation are processed respectively to every piece, then with two purt chew the main part and seal the rigid coupling, every half branch flow way in the main part is chewed the main part and another piece is chewed the corresponding position half branch way in the main part and is matees, can form a complete branch way that is arcuation. The single-head needle valve can realize quick color change.

Description

Single-head needle valve capable of rapidly changing color and preparation method thereof

Technical Field

The application relates to the technical field of hot nozzles, in particular to a single-head needle valve capable of rapidly changing colors and a preparation method thereof.

Background

At present, the plastic product is generally produced by injecting sizing material (molten plastic) into a mold by an injection molding machine under pressure, and cooling and molding the sizing material. The requirements on the appearance and quality of plastic products in the market are higher and higher, so that the development of hot runner technology is promoted, a hot runner device is divided into an open type hot nozzle and a needle valve type hot nozzle according to different hot nozzle structures, wherein the needle valve type hot nozzle has the advantage of being capable of realizing linear feeding of an injection molding center, a needle valve center and a pouring gate center, and the production of many plastic products adopts a single-head needle valve for feeding.

The hot runner of the common single-head needle valve is limited by a processing mode (a processing mode of sectionally and repeatedly drilling holes) and has turning corners at the intersection and the connection positions of the runners, a retaining phenomenon can occur on the corners of sizing materials (molten plastics), when plastic products with different colors are required to be prepared, the sizing materials with different colors need to be replaced in the single-head needle valve, and due to the existence of the retaining phenomenon, the runners of the replaced single-head needle valve are doped with sizing materials with other colors of the last injection molding, so that the colors of the sizing materials are not pure, and finally, the obtained plastic products have larger chromatic aberration, namely, quick color replacement cannot be realized; meanwhile, due to the position limitation, the nozzle body is provided with a section of heating wire which cannot be placed, so that the temperature of the sizing material at the position is lower, and the sizing material is remained on the wall of the runner to influence quick color change.

Disclosure of Invention

The main body part of the branch runner of the single-head needle valve is arc-shaped, and turning corners are not formed, so that glue stock is prevented from staying in the branch runner, and the requirement of quick color change is met; the preparation method is convenient for polishing the branch channels, and can polish the branch channels more smoothly and smoothly, thereby achieving the purpose of avoiding retention of sizing materials and meeting the requirement of quick color change.

In a first aspect, the preparation method of the single-head needle valve capable of changing color rapidly provided by the application adopts the following technical scheme:

the method comprises the following steps:

s1, a sprue main body consists of two halves, each sprue main body is respectively processed into two arc-shaped half branch flow passages, and each half branch flow passage on one sprue main body is matched with a half branch flow passage at a corresponding position on the other sprue main body, so that a complete arc-shaped branch flow passage can be formed;

s2, the main body of the sprue is formed by detachably connecting an upper sprue body and a lower sprue body, the half upper sprue body is fixedly connected in a sealing way, and the half lower sprue body is also fixedly connected in a sealing way;

s3, connecting a pumping nozzle head with an upper pumping nozzle body, embedding the upper pumping nozzle body into a cylinder core, embedding a valve needle into a lower pumping nozzle body, connecting the top end of the valve needle with the cylinder core, and finally sealing and fixing the upper pumping nozzle body and the lower pumping nozzle body;

and S4, firstly placing the pump nozzle head, the pump nozzle main body, the valve needle and the cylinder core which are assembled in the step 3 into the cylinder body, then placing the cylinder cover from the upper surface of the cylinder body, connecting the cylinder cover with the cylinder body, then placing the positioning ring from the lower surface of the cylinder body, connecting the positioning ring with the cylinder body, and finally sealing and connecting the nozzle body with the lower pump nozzle body.

Compared with the traditional single-head needle valve, the branch runner adopts the processing mode of sectioning many times multi-angle drilling, lead to there is turning formula's turning in branch runner and branch runner's junction, the phenomenon of detaining can appear in the corner position to the sizing material, doping has the sizing material of other colours of moulding plastics last time in the runner when changing the sizing material of different colours, and then can't realize quick colour change, in the scheme of this application, half branch runner is processed respectively to the main part with half the purt, then the main part is sealed rigid coupling is chewed to half the purt to the half, form complete branch runner, such processing mode does not receive the processing position restriction, can process into the arciform that does not have turning formula corner with branch runner according to fluidic flow law, reach the purpose that avoids the sizing material to detain, satisfy quick colour change's requirement.

Optionally, in step S1, the half-and-half pump body is a half pump body formed by splitting a whole pump body or a half pump body originally.

Preferably, the step S1 specifically includes: inputting a processing program of a needed arc-shaped half branch runner into a numerical control milling machine, and milling two arc-shaped half branch runners of each sprue main body by using a milling cutter.

Optionally, in step S1, the machining of each pump body is performed simultaneously or sequentially.

Preferably, the step S1 further includes surface polishing the half branch flow channel.

By adopting the technical scheme, the surface of the half branch flow channel is polished more smoothly and smoothly, the retention of sizing materials is better avoided, and the requirement of quick color change is met.

Optionally, in the step S2, a sealing and fixedly connecting manner is diffusion welding.

By adopting the technical scheme, the diffusion welding can not cause macroscopic deformation and melting of the upper sprue runner body and the lower sprue runner body, the welding precision is high, and the upper sprue runner body and the lower sprue runner body with higher dimensional precision can be obtained.

In a second aspect, the single-head needle valve capable of changing color rapidly provided by the application adopts the following technical scheme:

the valve body device comprises a sprue tip, a sprue main body and a sprue body which are fixedly connected with each other in sequence according to the flow direction of glue, the sprue tip and the sprue main body are arranged in the cylinder device, a glue inlet is formed in the center of the sprue tip, two branch passages communicated with the glue inlet are formed in the sprue main body, a main flow passage communicated with each branch passage is formed in the sprue body, the main body of each branch passage is arc-shaped, the sprue main body is formed by two half branch passages, two arc-shaped half branch passages are respectively processed in each sprue main body, then the two sprue main bodies are fixedly connected in a sealing mode, and each half branch passage in one sprue main body is matched with the half branch passage in the corresponding position in the other sprue main body, so that a complete arc-shaped branch passage can be formed.

Through adopting above-mentioned technical scheme, every tributary way's main part is the arcuation, does not have the turning type's of turning type corner, has avoided the tributary way of traditional single-end needle valve to have turning type corner to lead to the sizing material to detain in the corner easily and can't realize quick colour change's problem. In the scheme of this application, will half the main part is chewed to the purt earlier and half of branch channel is processed respectively, then will half the purt and chew the main part and seal the rigid coupling again, form complete branch channel, such processing method does not receive the processing position restriction, can be according to the flow law of fluid, process into the arcuation that does not have turning type turning corner with branch channel, the while is convenient polishes branch channel, can polish branch channel more smooth and easy and smooth with branch channel to reach the purpose that avoids the sizing material to detain, satisfy the requirement of quick colour change.

Optionally, the main body portion of the at least one branch runner is in a shape of a right circular arc or an elliptic arc.

By adopting the technical scheme, the main body part of the branch flow channel is in a right circular arc shape or an elliptic arc shape, so that the flow rule of fluid is met, the retention of sizing materials in the branch flow channel can be avoided, and the requirement of quick color change is met; meanwhile, the regular arc shape or the elliptic arc shape is in a regular shape, so that a corresponding machining program is conveniently input into the numerical control machine tool, the machining difficulty is reduced, and the machining efficiency is improved.

Preferably, the joint of the glue inlet and the branch runner is connected in an arc connection mode.

Through adopting above-mentioned technical scheme, the sizing material can be smooth and easy through when flowing through the junction of inlet and branch flow way, has avoided the sizing material to be detained in the junction of inlet and branch flow way to satisfy the requirement of quick colour change.

Preferably, the joint of the branch runner and the main runner is connected in a smooth transition mode.

Through adopting above-mentioned technical scheme, the sizing material can be smooth and easy through when flowing through the junction of branch flow channel and sprue, has avoided the sizing material to be detained in the junction of branch flow channel and sprue to satisfy the requirement of quick colour change.

Optionally, the single-end needle valve further comprises a heating device, the heating device comprises a first heating wire and a second heating wire, a first wire groove for placing the first heating wire is formed in the peripheral wall of the main body of the sprue, and the first heating wire is embedded into the first wire groove and used for heating the sizing material in the branch flow passage; the outer cover of the nozzle body is provided with a copper sleeve, the peripheral wall of the copper sleeve is provided with a second wire slot for placing a second heating wire, and the second heating wire is embedded into the second wire slot and used for heating sizing materials in the main runner.

By adopting the technical scheme, the proper temperature of the sizing material flowing through the branch runner and the main runner can be ensured, the problem that the fluidity of the sizing material is affected by cooling the sizing material with high melting point on the branch runner or the main runner, and the injection molding process is difficult to carry out smoothly is avoided, and therefore, the single-end needle valve can meet the processing of high-melting-point plastics; the copper sleeve can lead the nozzle body to be heated uniformly.

Preferably, the cross sections of the first heating wire and the first wire slot are semicircular.

Through adopting above-mentioned technical scheme, can increase the area of contact of main part is chewed with the purt to first heating wire, improve the heat utilization efficiency, make simultaneously first heating wire and the better laminating of first linear groove and then make the purt chew the main part and be heated more evenly, avoid local overheated phenomenon to lead to yellowing scheduling problem appears in the sizing material that is more sensitive to the temperature.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the main body part of the branch flow channel is arc-shaped, and turning corners are not formed, so that the glue stock is prevented from staying in the branch flow channel, and the requirement of quick color change is met;

2. the processing mode is convenient for polishing the branch flow passages, and the branch flow passages can be polished more smoothly and smoothly, so that the aim of avoiding retention of sizing materials is fulfilled, and the requirement of quick color change is met.

3. The positions of the heating lines are reasonably distributed, and the phenomenon that the quick color change is influenced due to retention phenomenon caused by low local sizing material temperature is avoided.

Drawings

FIG. 1 is a cross-sectional view of a single-head needle valve according to an embodiment of the present application;

FIG. 2 is another angular cross-sectional view of a single head needle valve according to an embodiment of the present application;

FIG. 3 is a schematic semi-sectional view of a single head needle valve according to an embodiment of the present application.

Reference numerals illustrate:

1. a valve body device; 11. a pump nozzle head; 111. a glue inlet; 12. a pump nozzle body; 121. a pumping nozzle body is arranged; 122. a lower sprue body; 123. a branch flow passage; 124. a first wire chase; 13. a nozzle body; 131. a main flow passage; 14. a valve needle; 15. a copper sleeve;

2. a cylinder device; 21. a cylinder cover; 211. a first airway; 22. a cylinder; 221. a second airway; 23. a positioning ring; 24. a cylinder core; 241. an annular portion; 242. a connection plate portion; 2421. a plug hole; 25. a first air chamber; 26. a second air chamber;

3. a heating device; 31. a first heating wire; 32. and a second heating wire.

Detailed Description

The present application is described in further detail below with reference to fig. 1-3.

The embodiment discloses a single-head needle valve capable of changing colors rapidly, and referring to fig. 1, the needle valve comprises a valve body device 1, a cylinder device 2 and a heating device 3. The valve body device 1 is used for accommodating the sizing material and guiding the flow direction of the sizing material, the cylinder device 2 is used for controlling the outflow of the sizing material in the valve body device 1, and the heating device 3 is used for heating the sizing material in the valve body device 1.

The body part of the valve body device 1 is arranged in the cylinder device 2, and the valve body device 1 comprises a pump nozzle head 11, a pump nozzle body 12 and a nozzle body 13 which are connected in sequence through threads according to the glue flow direction, and a valve needle 14 arranged in the valve body device 1. The main body 12 is chewed to the purt including last purt body 121 and lower purt body 122, go up the purt and chew the body 122 and pass through the bolt fastening that the purt chews the center of first 11 and offered into gluey mouth 111, set up two and advance gluey mouthful branch way 123 that communicate with gluey mouth 111 in the purt main body 12, advance gluey mouth 111 and branch way 123 the mode that links up of linking department adopts the circular arc to link up for the sizing material can smooth and easy pass through when flowing through the linking department that advances gluey mouth 111 and branch way 123. The main part of every branch channel 123 is oval arcuation, and the effect has two, and on the one hand, makes things convenient for the sizing material to follow branch channel 123 homeowner and descend, on the other hand, has avoided turning formula's turning, effectively avoids the sizing material to be detained at branch channel 123 to the inhomogeneous problem of colour change appears when avoiding needing to trade the colour, satisfies the requirement of quick colour change. The main runner 131 communicated with each of the branch runners 123 is formed in the nozzle body 13, and the joint of the branch runner 123 and the main runner 131 is in smooth transition, so that the sizing material can smoothly pass through the joint of the branch runner 123 and the main runner 131.

In other embodiments, the main body portion of the branch flow channel 123 may be in a right circular arc shape, the right circular arc-shaped branch flow channel 123 is longer than the flow path of the elliptical arc-shaped branch flow channel 123, so that the flow velocity of the sizing material at the junction of the two branch flow channels 123 can be reduced, the turbulence of the sizing material at the junction is reduced, the sizing material at the junction of the two branch flow channels 123 is prevented from being retained on the inner wall of the branch flow channel 123 to affect quick color change, and the right circular arc-shaped processing procedure is simpler and more convenient to input in the numerically controlled milling machine.

Referring to fig. 1 and 2, the cylinder device 2 includes a cylinder head 21, a cylinder block 22 and a positioning ring 23 which are sequentially bolted in the flow direction of the rubber, and a core 24 which is nested in the cylinder block 22. The main nozzle body 12 is nested in the cylinder core 24, and the cylinder cover 21 and the positioning ring 23 are respectively abutted with the main nozzle body 12 and fix the main nozzle body 12 inside the cylinder device 2; the cylinder core 24 comprises an annular part 241 and a connecting plate part 242 integrally formed with the annular part 241, the annular part 241 is abutted against the cylinder cover 21 and the cylinder body 22, the connecting plate part 242 is provided with an inserting hole 2421 for connecting the valve needle 14, and the top end of the valve needle 14 is fixedly inserted into the inserting hole 2421; the cylinder core 24, the cylinder cover 21 and the cylinder body 22 are matched to form a first air cavity 25 and a second air cavity 26, a first air channel 211 is formed on one side of the cylinder cover 21, one end of the first air channel 211 is communicated with the first air cavity 25, and the other end of the first air channel is communicated with an air source; a second air channel 221 is formed in one side of the cylinder 22, one end of the second air channel 221 is communicated with the second air cavity 26, and the other end of the second air channel is communicated with an air source. When compressed gas is introduced into the second air channel 221, the compressed gas enters the second air cavity 26 through the second air channel 221 so as to lift the cylinder core 24, and further drive the valve needle 14 to lift so that the sizing material in the main flow channel 131 can flow out; when compressed gas is introduced into the first air passage 211, the compressed gas enters the first air chamber 25 through the first air passage 211 to enable the cylinder core 24 to drop, and then drive the valve needle 14 to drop so that the valve needle 14 blocks the outlet of the main flow passage 131, the glue stock in the main flow passage 131 cannot flow out, and glue injection is stopped.

Referring to fig. 2 and 3, the heating device 3 includes a first heating wire 31 and a second heating wire 32, a first wire groove 124 for placing the first heating wire 31 is formed on the peripheral wall of the nozzle main body 12, the first heating wire 31 is embedded in the first wire groove 124 and used for heating the glue stock in the branch flow channel 123, so that the temperature of the glue stock is ensured to be suitable when the glue stock flows through the branch flow channel 123; the copper bush 15 is sleeved outside the nozzle body 13, a second wire slot for placing a second heating wire 32 is formed in the peripheral wall of the copper bush 15, the second heating wire 32 is embedded into the second wire slot and used for heating the sizing material in the main runner 131, the proper temperature of the sizing material flowing through the main runner 131 is ensured, and the nozzle body 13 can be uniformly heated by the copper bush 15. The problem that the fluidity of the sizing material is affected by cooling the sizing material with high melting point on the branch runner 123 or the main runner 131 by the heating device 3, so that the injection molding process is difficult to smoothly proceed is avoided, and the single-head needle valve can meet the processing requirement of high-melting-point plastics.

As the preferred embodiment, the cross sections of the first heating wire 31 and the first wire slot 124 are semicircular, and this solution can increase the contact area between the first heating wire 31 and the main body 12 of the sprue, improve the heat utilization rate, and simultaneously make the first heating wire 31 and the first wire slot 124 better fit, so that the main body 12 of the sprue is heated more uniformly, and avoid the problems of yellowing of the material sensitive to temperature caused by local overheating.

The pump nozzle head 11 is in threaded connection with the pump nozzle main body 12, and the pump nozzle head 11 is tightly connected with the pump nozzle main body 12 through the locking force of the screw teeth, so that glue leakage is avoided at the joint of the pump nozzle head 11 and the pump nozzle main body 12; simultaneously, the pump nozzle head 11 is submerged into the pump nozzle main body 12, the heat conduction area is larger, and the glue inlet 111 is closer to the first heating wire 31, so that the influence of the cooling of the glue at the glue inlet 111 and the influence of the retention of the glue on the inner wall of the glue inlet 111 on the quick color change is avoided.

The main body 12 of the sprue is in threaded connection with the nozzle body 13, the main body 12 of the sprue is tightly connected with the nozzle body 13 by the locking force of the screw teeth, and the glue leakage at the joint of the main body 12 of the sprue and the nozzle body 13 is avoided; meanwhile, the bottom end of the main body 12 of the sprue is sunk into the nozzle body 13 deeper, so that the bottom end of the branch flow passage 123 is closer to the second heating wire 32, and the phenomenon that the quick color change is influenced due to the fact that the sizing material at the bottom end of the branch flow passage 123 is cooled and then stays on the inner wall of the branch flow passage 123 is avoided.

The preparation method of the single-head needle valve in the embodiment comprises the following steps:

step S1, a main nozzle body 12 is composed of two half-pieces, each main nozzle body 12 is respectively processed into two arc-shaped half branch flow passages, each half branch flow passage on one main nozzle body 12 is matched with a half branch flow passage at a corresponding position on the other main nozzle body 12, and a complete arc-shaped branch flow passage 123 can be formed; and then polishing the surface of the half branch runner, so that the surface of the half branch runner is polished more smoothly and smoothly, the retention of sizing materials is better avoided, and the requirement of quick color change is met. The half of the main body 12 is formed by cutting the whole main body 12 into half main body 12 or the main body 12 is half, and the processing of each main body 12 is performed simultaneously or sequentially.

Step S2: the main body 12 is formed by detachably connecting an upper nozzle body 121 and a lower nozzle body 122, and the upper nozzle body 121 in half is fixedly sealed, and the lower nozzle body 122 in half is also fixedly sealed. Diffusion welding does not cause macroscopic deformation and melting of upper and lower nozzle bodies 121 and 122, and welding accuracy is high, so that upper and lower nozzle bodies 121 and 122 having high dimensional accuracy can be obtained.

Step S3: the upper nozzle body 121 is sealed and fixed by connecting the upper nozzle head 11 with the upper nozzle body 121, embedding the upper nozzle body 121 into the cylinder core 24, embedding the valve needle 14 into the lower nozzle body 122, connecting the top end of the valve needle 14 with the cylinder core 24, and finally sealing and fixing the upper nozzle body 121 and the lower nozzle body 122.

Step S4: the pump nozzle head 11, the pump nozzle main body 12, the valve needle 14 and the cylinder core 24 which are assembled in the step S3 are firstly put into the cylinder body 22, then the cylinder cover 21 is put into the cylinder body 22 from the upper surface of the cylinder body 22, the cylinder cover 21 is connected with the cylinder body 22, the positioning ring 23 is put into the cylinder body 22 from the lower surface of the cylinder body 22, the positioning ring 23 is connected with the cylinder body 22, and finally the nozzle body 13 is connected with the lower pump nozzle body 122 in a sealing way.

The branch channel 123 is formed by processing half of the main body 12 of the half pump nozzle respectively, and then sealing and fixedly connecting the main body 12 of the half pump nozzle to form the complete branch channel 123, so that the processing mode is not limited by processing positions, and the branch channel 123 can be processed into an arc shape without turning corners according to the flow rule of fluid, thereby achieving the purpose of avoiding glue stock retention and meeting the requirement of quick color change.

The implementation principle of the single-head needle valve in the embodiment of the application is as follows: the single-head needle valve needs to realize quick color change, and the flow passage needs to ensure that no turning type corner exists and accords with the flow rule of fluid; the temperature of the whole system needs to be kept stable and balanced, and the situation that the local temperature is too high or too low cannot occur. In this embodiment, half of the branch flow channel 123 is processed by the half-and-half pump nozzle body 12, the surface of the branch flow channel 123 is polished, and then the half-and-half pump nozzle body 12 is welded together by diffusion welding process to form a complete branch flow channel 123, so that the processing mode is not limited by the processing position, and the branch flow channel 123 can be processed into an arc shape without turning corners according to the flow rule of fluid; meanwhile, the processing mode is convenient for polishing the branch flow channel 123, so that the branch flow channel 123 can be polished more smoothly and smoothly, thereby avoiding the retention of sizing materials in the branch flow channel 123 and meeting the requirement of quick color change; in addition, the heating lines are distributed reasonably, and the situation that the quick color change is affected due to the fact that the rubber is retained on the inner wall of the branch runner 123 or the main runner 131 due to the fact that the local rubber temperature is low is avoided.

The embodiments of this embodiment are all preferred embodiments of the present application, and are not intended to limit the scope of the present application, in which like parts are denoted by like reference numerals. Therefore: all equivalent changes in structure, shape and principle of this application should be covered in the protection scope of this application.

Claims

1. The preparation method of the single-head needle valve capable of changing colors rapidly is characterized by comprising the following steps of:

the method comprises the steps of S1, forming a sprue main body (12) by two halves, respectively processing each sprue main body (12) into two arc-shaped half branch channels, wherein each half branch channel on one sprue main body (12) is matched with a half branch channel at a corresponding position on the other sprue main body (12), and a complete arc-shaped branch channel (123) can be formed;

s2, the main body (12) of the pump nozzle is formed by detachably connecting an upper pump nozzle body (121) and a lower pump nozzle body (122), the upper pump nozzle body (121) in half is fixedly connected in a sealing way, and the lower pump nozzle body (122) in half is also fixedly connected in a sealing way;

s3, connecting a pumping nozzle head (11) with an upper pumping nozzle body (121), embedding the upper pumping nozzle body (121) into a cylinder core (24), embedding a valve needle (14) into a lower pumping nozzle body (122), connecting the top end of the valve needle (14) with the cylinder core (24), and finally sealing and fixing the upper pumping nozzle body (121) and the lower pumping nozzle body (122);

s4, firstly placing the pump nozzle head (11), the pump nozzle main body (12), the valve needle (14) and the cylinder core (24) which are assembled in the step S3 into the cylinder body (22), then placing the cylinder cover (21) from the upper surface of the cylinder body (22) and connecting the cylinder cover (21) with the cylinder body (22), then placing the positioning ring (23) from the lower surface of the cylinder body (22) and connecting the positioning ring (23) with the cylinder body (22), and finally sealing and connecting the nozzle body (13) with the lower pump nozzle body (122).

2. The method for preparing a quick color change single-head needle valve according to claim 1, wherein in the step S1, the half-part pump nozzle body (12) is a half pump nozzle body (12) formed by cutting a whole pump nozzle body (12) or a half pump nozzle body (12) originally.

3. The method for preparing a single-head needle valve capable of changing color rapidly according to claim 1, wherein the step S1 is specifically: inputting a machining program of a needed arc-shaped half branch runner into a numerical control milling machine, and milling two arc-shaped half branch runners of each sprue main body (12) by using a milling cutter.

4. A method for manufacturing a quick color change single-head needle valve according to claim 1 or 3, characterized in that in step S1, the machining of each pump nozzle body (12) is performed simultaneously or sequentially.

5. The method for manufacturing a single-head needle valve capable of changing color rapidly according to claim 1, wherein the step S1 further comprises surface polishing the half branch flow passage.

6. The method for preparing a single-end needle valve capable of changing color rapidly according to claim 1, wherein in the step S2, the sealing and fixedly connecting mode is diffusion welding.

7. The utility model provides a but single-end needle valve of quick colour change, includes valve body device (1) and cylinder device (2), valve body device (1) are including the purt of following the glue flow direction and being chewed first (11), purt and chew main part (12) and chew body (13) of mutual rigid coupling in proper order, the purt is chewed first (11) and is chewed main part (12) and locates inside cylinder device (2), the center that is chewed first (11) of purt has been seted up into gluey mouth (111), set up two branch ways (123) with advance gluey mouth (111) intercommunication in purt main part (12), set up in mouth main part (13) one and each branch way (123) all intercommunication main part (131), its characterized in that, the method of seting up of branch way (123) is that is, and one is chewed main part (12) by two and is chewed main part (12) and be processed two and be the form the half branch way respectively, then with the branch way that two branch ways (12) are half the branch way and the one and the branch way is chewed the position is corresponding to the one and is chewed main part (12) and form one and be full, the branch way is formed the arc of the branch way is the branch way of the other and is full.

8. The quick-change single-head needle valve according to claim 7, wherein the main body portion of the at least one branch passage (123) is in a shape of a right circular arc or an elliptical arc.

9. The quick-change single-head needle valve according to claim 7 or 8, wherein the joint of the glue inlet (111) and the branch flow channel (123) is joined in a circular arc joint manner.

10. The quick-change single-head needle valve according to claim 7 or 8, wherein the junction of the branch flow passage (123) and the main flow passage (131) is joined in a smooth transition manner.