Screw valve and method for controlling adhesive discharge therefrom

Abstract

This application discloses a screw valve and a method for controlling the dispensing of adhesive. The screw valve (100) includes a valve seat (1), a driver (2), a stator assembly (3), a screw (4), and a needle (6). The upper end of the stator assembly (3) is provided with a liquid adhesive inlet (11). The screw (4) is movably connected to the stator assembly (3) and is power-transmittingly connected to the power output end of the driver. The screw (4) is provided with a spiral groove (12) communicating with the liquid adhesive inlet (11). The magnetic attraction of the magnetic screw or insert to the iron oxide particles in the magnetic adhesive can offset the gravity of the iron oxide particles themselves, eliminating the effect of the gravity of the iron oxide particles on the control of the adhesive dispensing amount. This stabilizes the dispensing of the magnetic adhesive, increases the accuracy of the dispensing amount control, and even enables the dispensing of minute amounts of adhesive.

Description

[Technical Field]

[0001] This application claims priority to a Chinese patent application filed with the State Intellectual Property Office of the People's Republic of China on September 7, 2022, bearing application number 202211087507.6 and entitled "Screw valve with high accuracy of magnetic adhesive dispensing and method for controlling adhesive dispensing therefrom," the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of screw valves, and more particularly to a screw valve and a method for controlling the dispensing of adhesive therefrom. [Background technology]

[0003] Currently, as medium to high viscosity particle adhesives are used for a variety of purposes, the types of particle materials and particle sizes are increasing. However, in actual applications, the conventional concentric screw valve cannot simultaneously apply different particles because the rotor and stator have the same size.

[0004] Magnetic adhesive refers to a liquid adhesive containing iron oxide particles. Such liquid adhesives have a high metal particle content, resulting in high density and low adhesive viscosity. However, the iron oxide particles contained in magnetic adhesives affect the control of adhesive dispensing volume using conventional screw valves. As a result, conventional screw valves and dispenser controllers are unable to stably and accurately control the dispensing volume of such adhesives, and especially when the adhesive dispensing volume is small, they are unable to control dispensing accuracy, resulting in serious problems of adhesive dripping and leakage. Summary of the Invention [Problem to be solved by the invention]

[0005] The present application aims to solve at least one of the technical problems existing in the prior art.

[0006] Therefore, the present application proposes a screw valve and a method for controlling adhesive discharge that have the advantages of high control accuracy over the amount of magnetic adhesive discharged, enabling minute amounts of magnetic adhesive to be discharged, and effectively preventing dripping and leakage of the magnetic adhesive. [Means for solving the problem]

[0007] A screw valve according to an embodiment of the first aspect of the present application includes a valve seat, a driver attached to the valve seat, a stator assembly mounted on the valve seat and having a liquid adhesive inlet at its upper end, a screw movably connected to the stator assembly and power-transmittingly connected to the power output end of the driver so as to drive the screw's own rotation, the screw having a spiral groove communicating with the liquid adhesive inlet, and a needle located below the stator assembly and connected to the stator assembly, the needle having an internal passage communicating with the spiral groove, wherein the screw or the stator assembly is magnetic, and when the magnetic adhesive flows through the spiral groove, the magnetic screw or the stator assembly has a magnetic attraction force to iron oxide particles in the magnetic adhesive to offset the gravity of the iron oxide particles in the magnetic adhesive.

[0008] In the screw valve of the present application, when the screw valve rotates to dispense the adhesive, the magnetic screw or stator assembly has a magnetic attraction force that can offset the gravity of the iron oxide particles in the magnetic adhesive, thereby eliminating the effect of the gravity of the iron oxide particles themselves on controlling the amount of adhesive dispensed, and improving the accuracy of controlling the amount of adhesive dispensed.

[0009] Furthermore, the magnetic attraction of the screw or stator assembly can offset the effect of the gravity of the iron oxide particles themselves on the dispensing amount, allowing for stable dispensing of minute amounts of adhesive. However, without the magnetic attraction of the screw or stator assembly, the magnetic adhesive would have a high metal particle content and high density due to the action of the iron oxide particles in the magnetic adhesive, resulting in low adhesive viscosity and a large increase in adhesive dispensing amount due to the gravity of the metal particles, resulting in an unstable dispensing amount. The screw valve of the present application can effectively avoid these problems, stabilize the dispensing amount, and allow for stable dispensing of minute amounts of adhesive.

[0010] When the adhesive discharge stops, the iron oxide particles in the magnetic adhesive can be attracted by the screw or stator assembly due to the magnetic attraction of the screw or stator assembly to the iron oxide particles in the magnetic adhesive, effectively preventing the magnetic adhesive from automatically leaking due to the presence of iron oxide particles, allowing for quick discharge halt and preventing dripping and leakage of the magnetic adhesive.

[0011] The stator assembly further includes a stator attached to the valve seat, with the liquid adhesive inlet at its upper end and movably connected to the screw, and a magnetic nest disposed between the stator and the screw, fixedly connected to the stator, and within which the screw can rotate.

[0012] Furthermore, a fastener is provided at the lower end of the stator, a portion of the needle is attached to the fastener, and the fastener is fixedly connected to the stator. The fastener functions to fasten the needle, making it easy to attach the needle.

[0013] Furthermore, both the stator and the fastener are made of diamagnetic materials, and both have demagnetizing functions, preventing external magnetic fields from interfering with the magnetism of the screw or insert, and preventing the influence of external magnetic fields on the iron oxide particles in the magnetic adhesive.

[0014] Furthermore, the outer surface of the insert is a conical surface. The outer surface of the insert is arranged on the conical side, which can better ensure concentricity between the insert and the screw, and between the insert and the stator. The conical side can better satisfy the requirement for the gap between the insert and the stator when installing the insert.

[0015] Furthermore, the stator is provided with a locking screw that is threaded into the stator and abuts against the outer wall of the insert to prevent the insert from loosening. By fastening the locking screw, the insert can be prevented from loosening, the insert can be attached to the stator more stably, and unstable discharge volume caused by the insert loosening can be avoided.

[0016] The present application further provides a method for controlling adhesive dispensing of a screw valve, the screw valve including a driver, a stator assembly, a screw, a needle, and a fastener, the stator assembly including a stator and an insert, a liquid adhesive inlet provided at an upper end of the stator assembly, and a spiral groove provided on the screw for communicating with the liquid adhesive inlet, the method for controlling adhesive dispensing includes: Step S1 of magnetizing the screw or the insert to provide magnetism to the screw or the insert; Step S2: attaching the insert to the stator, then attaching the needle and the fastener to the lower end of the stator, and then further attaching the screw; and step S3, when dispensing with a dispenser, controlling the driver to drive the screw to rotate in the normal direction, thereby rotating the screw and simultaneously moving the magnetic adhesive in the spiral groove, If the magnetic attraction force of the screw or the insert to the iron oxide particles in the magnetic adhesive is F1, the gravity of the iron oxide particles in the magnetic adhesive is F2, the adhesive force of the liquid adhesive in the magnetic adhesive is F3, and the thrust force on the magnetic adhesive when the screw is rotated is F4, then F1≧F2 and F1+F3≦F2+F4.

[0017] In the method for controlling the adhesive discharge from the screw valve in this application, by controlling F1≧F2 and F1+F3≦F2+F4, when the adhesive is discharged from the screw valve, the magnetic attraction force of the screw or insert can offset the gravity of the iron oxide particles, and the discharge of the magnetic adhesive is stabilized by the action of the screw thrust, which increases the accuracy of control over the discharge amount and enables the discharge of minute amounts of adhesive.

[0018] Furthermore, after step S3, the adhesive discharge control method further includes step S4, in which during the forward rotation period of the screw, the fluid pressure at the liquid adhesive inlet and the fluid pressure at the lower end of the spiral groove are controlled, where the fluid pressure at the lower end of the spiral groove is Fa and the fluid pressure at the liquid adhesive inlet is Fb, and both Fa and Fb are downward.By setting Fa≧Fb, the magnetic adhesive moves toward the lower end of the spiral groove due to the rotation of the screw and the action of the magnetic attraction force F1, and enters the needle from the lower end of the spiral groove, so that the discharge amount is discharged while being stably controlled.

[0019] Furthermore, after step S4, the adhesive dispensing control method includes: When the screw stops discharging adhesive, the screw is changed from a forward rotation state to a reverse rotation state, and if the screw reversal time is t, the rotation of the screw is stopped after the screw reversal time t has elapsed, and when the screw reversal period and rotation have stopped, the method further includes step S5 where F2≦F1+F3, and after the screw reversal period and rotation have stopped, the magnetic adhesive is attracted to the screw or the insert due to the action of the magnetic attraction force F1 of the screw or the insert on the iron oxide particles in the magnetic adhesive.

[0020] When the screw valve stops dispensing adhesive, the magnetic adhesive can be prevented from dripping or leaking due to inertia during the screw reversal time t, and the magnetic adhesive in the spiral groove exerts a thrust in the direction opposite to the direction of movement during reversal, allowing the adhesive to be quickly stopped from being dispensed. Moreover, by ensuring that F2≦F1+F3, the screw or insert can adsorb the iron oxide particles in the magnetic adhesive when the screw reverses and stops rotating, effectively preventing leakage of the magnetic adhesive and quickly stopping the adhesive from being dispensed.

[0021] Furthermore, in step S1, the magnetic field applied to the screw or insert is φ, and φ is in the range of 5 mT≦φ≦300 mT. By controlling the applied magnetic field φ, it is possible to avoid the magnetic attraction force becoming too large when the applied magnetic field is too large, and also to avoid the iron oxide particles in the magnetic adhesive being difficult to discharge from the spiral groove together with the magnetic adhesive due to the magnetic attraction force being too large. On the other hand, when the applied magnetic field is too small, it is difficult to achieve the magnetic attraction force to offset the effect of the gravity of the iron oxide particles on the amount of magnetic adhesive discharged.

[0022] Furthermore, the screw rotation speed is v, and v≦300 rpm. By controlling the screw rotation speed to within 300 rpm, the precision of the adhesive discharge amount can be more precisely controlled, but if the screw rotation speed exceeds 300 rpm, the precision of the adhesive discharge decreases.

[0023] Furthermore, in step S5, the screw reversal time is 0.1 seconds≦t≦0.6 seconds.

[0024] Furthermore, the ratio of the fluid pressure Fa at the bottom end of the spiral groove to the fluid pressure Fb at the inlet of the liquid adhesive is Fa / Fb = (1 to 5): 1. By setting the ratio of Fa to Fb to Fa / Fb = (1 to 5): 1, it is possible to control Fa and Fb even better.

[0025] Furthermore, in step S3, F2 + F4 - (F1 + F3) ≥ F2, where F2 is the gravity of the iron oxide particles added to the magnetic adhesive and is known. By satisfying F2 + F4 - (F1 + F3) ≥ F2, the control function of the magnetic attraction force F1 relative to the accuracy of the adhesive dispensing amount can be further stabilized, further stabilizing the dispensing amount and increasing the accuracy of the control of the dispensing amount.

[0026] Furthermore, in step S5, 0.5×F2≦F1+F3−F2≦F2 and F1+F3−F2≧Fa−Fb. This further stabilizes the function of preventing the magnetic adhesive from dripping or leaking by the magnetic attraction force F1, and further improves the stability of the function of quickly stopping the adhesive from being dispensed.

[0027] Furthermore, in step S3, the thrust force F4 on the magnetic adhesive when the screw rotates is calculated as v × K, where v is the screw rotation speed and K is a constant. Here, the value of the constant K is within the range of 0.001 × F2 to 0.05 × F2, including the endpoints 0.001 × F2 and 0.05 × F2, and F2 is the gravity of the iron oxide particles added to the magnetic adhesive, which is known. Thus, by adjusting the screw rotation speed, the thrust force F4 can be controlled and adjusted, making it easier to control the accuracy of the discharge amount.

[0028] The beneficial effects of this application are as follows: By controlling F1≧F2 and F1+F3≦F2+F4 during the process of rotating the screw valve to dispense the adhesive, the magnetic screw or insert has a magnetic attraction force that can offset the gravity of the iron oxide particles in the magnetic adhesive, eliminating the effect of the gravity of the iron oxide particles themselves on the control of the dispensed amount. Moreover, the action of the screw thrust stabilizes the dispensed magnetic adhesive, increasing the precision of the dispensed amount control and enabling the dispensed amount to be dispensed in minute amounts.

[0029] Furthermore, the magnetic attraction of the screw or insert can offset the effect of the gravity of the iron oxide particles themselves on the amount of dispensing, allowing for stable dispensing of minute amounts of adhesive. However, without the magnetic attraction of the screw or insert, the iron oxide particles in the magnetic adhesive would cause the magnetic adhesive to have a high metal particle content and high density, resulting in low adhesive viscosity, and the amount of adhesive dispensed would increase significantly due to the gravity of the metal particles, resulting in an unstable dispense rate. The screw valve of the present application can effectively avoid these problems, allowing for stable dispensing of minute amounts of adhesive.

[0030] When the adhesive discharge stops, the iron oxide particles in the magnetic adhesive can be attracted by the screw or insert due to the magnetic attraction of the screw or insert to the iron oxide particles in the magnetic adhesive. This prevents the magnetic adhesive from automatically leaking due to the presence of the iron oxide particles, allowing for quick discharge halt and preventing the magnetic adhesive from dripping or leaking.

[0031] Additional aspects and advantages of the present application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present application. [Brief explanation of the drawings]

[0032] The above and additional aspects and advantages of the present invention will become more apparent and easier to understand from the following detailed description of the preferred embodiments taken in conjunction with the accompanying drawings. [Figure 1] 1 is a schematic cross-sectional view of a screw valve according to the present invention. [Figure 2] FIG. 2 is an enlarged view of a portion A in FIG. [Figure 3] 4 is a flowchart of a method for controlling adhesive dispensing by a screw valve according to the present application. [Figure 4] 10 is another flowchart of the method for controlling adhesive dispensing by the screw valve according to the present application. DETAILED DESCRIPTION OF THE INVENTION

[0033] The following describes in detail the embodiments of the present application. Examples of the described embodiments are shown in the accompanying drawings, in which identical or similar elements, or elements having identical or similar functions, are designated by the same or similar reference numerals throughout. The following embodiments described with reference to the accompanying drawings are illustrative and are intended only to interpret the present application, and should not be understood as limiting the present application.

[0034] In the present description, it should be understood that orientations or positional relationships indicated by terms such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" are orientations or positional relationships shown in the accompanying drawings. These are merely for ease of explanation and simplification of the present description. They do not indicate or imply that the indicated devices or elements must have a particular orientation or be configured or operated in a particular orientation. As such, they should not be understood as limiting the present disclosure. In addition, elements qualified with "first" or "second" can expressly or implicitly include one or more of the elements. In the present description, unless otherwise specified, "plurality" means two or more than two.

[0035] In the description of this application, unless otherwise clearly specified or limited, the terms "attached," "coupled," and "connected" should be understood in a broad sense. For example, they may be understood as fixedly connected, detachably connected, integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intermediate medium, or internally connected between two elements. Those skilled in the art may understand the specific meanings of the above terms in this application depending on the specific situation.

[0036] 1 to 3, the screw valve 100 of the present application includes a valve seat 1, a driver 2, a stator assembly 3, a screw 4, and a needle 6. The driver 2 is attached to the valve seat 1, and the stator assembly 3 is mounted on the valve seat 1. A liquid adhesive inlet 11 is provided at the upper end of the stator assembly 3, and an adhesive bucket 9 is provided on one side of the stator assembly 3. The liquid adhesive inlet 11 and the adhesive bucket 9 are connected by an internal passage or internal pipeline. The screw 4 is movably connected to the stator assembly 3, and is power-transmittingly connected to the power output end of the driver 2 so as to drive the screw 4 to rotate. The screw 4 has a spiral groove 12 that is connected to the liquid adhesive inlet 11. The lower end of the spiral groove 12 is point a, and the liquid adhesive inlet 11 is located at point b. The needle 6 is located below the stator assembly 3 and is connected to the stator assembly 3, with the internal passage of the needle 6 communicating with the spiral groove 12.

[0037] The stator assembly 3 includes a stator 10 and a nest 5. The stator 10 is attached to the valve seat 1. A liquid adhesive inlet 11 is provided at the upper end of the stator 10. The screw 4 is movably connected to the stator 10. The nest 5 is provided between the stator 10 and the screw 4. The nest 5 is fixedly connected to the stator 10, and the screw 4 can rotate within the nest 5. The screw 4 or the stator assembly 3 is magnetic. For example, the screw 4 or the nest 5 is magnetic.

[0038] Since the screw 4 or the stator assembly 3 is magnetic (for example, the screw 4 or the insert 5 is magnetic), when the magnetic adhesive flows within the spiral groove 12, the magnetic screw 4 or the stator assembly 3 (for example, the insert 5 of the stator assembly 3) has a magnetic attraction force to the iron oxide particles in the magnetic adhesive, thereby offsetting the gravity of the iron oxide particles in the magnetic adhesive, thereby eliminating the effect of the gravity of the iron oxide particles themselves on the accuracy of the discharge amount of the magnetic adhesive, making it easier to achieve stable and precise control of the accuracy of the discharge amount.

[0039] In the screw valve 100 of the present application, during the process of the screw valve 100 rotating to discharge the adhesive, the magnetic screw 4 or insert 5 has a magnetic attraction force that can offset the gravity of the iron oxide particles themselves to the iron oxide particles in the magnetic adhesive, thereby eliminating the effect of the gravity of the iron oxide particles themselves on the control of the discharge amount, and improving the accuracy of control of the discharge amount.

[0040] Furthermore, the magnetic attraction of the screw 4 or the insert 5 can offset the effect of the gravity of the iron oxide particles themselves on the amount of dispensing, enabling stable dispensing of minute amounts of adhesive. Conversely, without the magnetic attraction of the screw 4 or the insert 5, the magnetic adhesive would have a high metal particle content and high density due to the action of the iron oxide particles, resulting in low adhesive viscosity. The amount of adhesive dispensed would increase significantly due to the action of the gravity of the metal particles, resulting in an unstable dispense rate. The screw valve 100 of the present application can effectively avoid these problems, stabilize the amount of adhesive dispensed, and enable stable dispensing of minute amounts of adhesive.

[0041] When the discharge of the adhesive stops, the iron oxide particles in the magnetic adhesive can be attracted by the screw 4 or the insert 5 due to the magnetic attraction force of the screw 4 or the insert 5 to the iron oxide particles in the magnetic adhesive, so that the magnetic adhesive does not automatically leak due to the presence of the iron oxide particles, and discharge can be stopped quickly, preventing dripping and leakage of the magnetic adhesive.

[0042] A fastener 7 was provided at the bottom end of the stator 10, and a portion of the needle 6 was mounted within the fastener 7, which was fixedly connected to the stator 10. Specifically, the fastener 7 was threadedly engaged with the stator 10. The fastener 7 served to fasten the needle 6 and facilitate the installation of the needle 6. Both the stator 10 and the fastener 7 were made of a diamagnetic material. Both the stator 10 and the fastener 7 served to demagnetize the screw 4 or the insert 5, preventing interference with the magnetism of the screw 4 or the insert 5 due to external magnetic fields, and also preventing the iron oxide particles in the magnetic adhesive from being affected by external magnetic fields.

[0043] The outer surface of the insert 5 is a conical surface. The outer surface of the insert 5 is arranged on the conical side, which can better ensure coaxiality between the insert 5 and the screw 4 and between the insert 5 and the stator 10, and the conical side can better satisfy the requirement for the gap between the insert 5 and the stator 10 when the insert 5 is installed.

[0044] The stator 10 is provided with a locking screw 8, which is threaded into the stator 10 and abuts against the outer wall of the insert 5 to prevent the insert 5 from loosening. By fastening the locking screw 8, the insert 5 can be prevented from loosening, the attachment of the insert 5 to the stator 10 can be made more stable, and unstable discharge volume caused by the insert 5 becoming loose can also be avoided.

[0045] The present application further provides a method for controlling adhesive dispensing in a screw valve, the screw valve including a driver, a stator assembly, a screw, a needle, and a fastener, the stator assembly including a stator and a nest, a liquid adhesive inlet provided at the upper end of the stator assembly, and a spiral groove provided on the screw for communicating with the liquid adhesive inlet. The screw valve is the screw valve 100 according to any of the above embodiments of the present application. Referring to FIG. 3, the method for controlling adhesive dispensing includes:

[0046] Step S1 of magnetizing the screw or insert to provide magnetism to the screw or insert; Step S2 of assembling the screw valve, specifically, attaching the insert to the stator, then attaching the needle and fastener to the lower end of the stator, and then attaching the screw; When applying with a dispenser, the method includes step S3 of controlling the driver to drive the screw to rotate in the normal direction, thereby rotating the screw and linking it so that the magnetic adhesive moves within the spiral groove, where F1 is the magnetic attraction force of the screw or insert to the iron oxide particles in the magnetic adhesive, F2 is the gravity of the iron oxide particles in the magnetic adhesive, F3 is the adhesive force of the liquid adhesive in the magnetic adhesive, and F4 is the thrust force on the magnetic adhesive when the screw is rotated, and F1≧F2 and F1+F3≦F2+F4.

[0047] In the method for controlling the discharge of adhesive from a screw valve in this application, by controlling F1≧F2 and F1+F3≦F2+F4, when the screw valve discharges adhesive, the magnetic attraction force of the screw or insert can offset the gravity of the iron oxide particles, and the discharge of the magnetic adhesive is stabilized by the action of the screw thrust, improving the control accuracy of the discharge amount and enabling the discharge of minute amounts of adhesive.

[0048] Further, referring to FIG. 4, after step S3, the adhesive dispensing control method includes: During the period when the screw is rotating in the forward direction, the fluid pressure at the inlet of the liquid adhesive and the fluid pressure at the lower end of the spiral groove are controlled, and if the fluid pressure at the lower end of the spiral groove is Fa and the fluid pressure at the inlet of the liquid adhesive is Fb, then step S4 is further included in which both Fa and Fb are directed downward, and by making Fa≧Fb, the magnetic adhesive moves stably toward the lower end of the spiral groove due to the rotation of the screw and the action of the magnetic attraction force F1, and enters the needle from the lower end of the spiral groove, and is discharged with the discharge amount kept stably controlled.

[0049] Further, referring to FIG. 4, the adhesive dispensing control method includes, after step S4: When the screw stops discharging, the screw is changed from a forward rotation state to a reverse rotation state. If the screw reverse time is t, the screw rotation is stopped after the screw reverse time t has elapsed. When the screw reverse period and rotation have stopped, the method further includes step S5, where F2≦F1+F3. After the screw reverse period and rotation have stopped, the magnetic adhesive is attracted to the screw or insert due to the magnetic attraction force F1 of the screw or insert to the iron oxide particles in the magnetic adhesive. This effectively prevents leakage of the magnetic adhesive when the screw reverse period and rotation have stopped.

[0050] For example, in step S5, the screw reversal time is 0.1 seconds≦t≦0.6 seconds.

[0051] When the screw valve stops dispensing adhesive, dripping and leakage of the magnetic adhesive due to inertial force during screw reversal time t can be effectively prevented, and the magnetic adhesive in the spiral groove exerts a thrust in the direction opposite to the direction of movement during reversal, allowing adhesive dispensing to be quickly stopped. Moreover, by ensuring that F2≦F1+F3, when the screw reverses and stops rotating, the screw or insert can absorb the iron oxide particles in the magnetic adhesive, effectively preventing leakage of the magnetic adhesive and also quickly stopping adhesive dispensing.

[0052] In step S1, the magnetic field φ applied to the screw or insert is in the range of 5 mT≦φ≦300 mT. Controlling the applied magnetic field φ prevents the magnetic attraction force from increasing when the applied magnetic field is too large, and also prevents the iron oxide particles in the magnetic adhesive from being difficult to discharge from the spiral grooves along with the magnetic adhesive due to the magnetic attraction force being too large. On the other hand, when the applied magnetic field is too small, it becomes difficult to offset the gravity of the iron oxide particles relative to the amount of magnetic adhesive dispensed by the magnetic attraction force.

[0053] The screw rotation speed is v, and v≦300 rpm. By controlling the screw rotation speed to within 300 rpm, the discharge amount can be controlled more precisely, but if the screw rotation speed exceeds 300 rpm, the adhesive discharge accuracy will decrease.

[0054] The ratio of the fluid pressure Fa at the bottom end of the spiral groove to the fluid pressure Fb at the inlet of the liquid adhesive is Fa / Fb = (1 to 5): 1. By setting the ratio of Fa to Fb to Fa / Fb = (1 to 5): 1, better control over Fa and Fb can be achieved.

[0055] In step S3, F2 + F4 - (F1 + F3) ≥ F2, where F2 is the gravity of the iron oxide particles added to the magnetic adhesive and is known. By satisfying F2 + F4 - (F1 + F3) ≥ F2, the control function of the magnetic attraction force F1 relative to the accuracy of the adhesive dispensing amount can be further stabilized, further stabilizing the dispensing amount and increasing the accuracy of the control of the dispensing amount.

[0056] In step S5, 0.5×F2≦F1+F3−F2≦F2 and F1+F3−F2≧Fa−Fb. When the magnetic adhesive is placed in this manner, the magnetic attraction force F1 can be used to further stabilize the function of preventing the magnetic adhesive from dripping or leaking, and the stability of the function of quickly stopping the adhesive from being dispensed can be further improved.

[0057] In step S3, the thrust force F4 on the magnetic adhesive when the screw rotates is calculated as v × K, where v is the screw rotation speed and K is a constant. The value of the constant K ranges from 0.001 × F2 to 0.05 × F2, including the endpoints 0.001 × F2 and 0.05 × F2, where F2 is the known gravity of the iron oxide particles added to the magnetic adhesive. When set up in this way, the thrust force F4 can be controlled and adjusted by adjusting the screw rotation speed, facilitating control over the precision of the discharge volume.

[0058] The beneficial effects of the adhesive dispensing control method of the present application are as follows: By controlling F1 ≥ F2 and F1 + F3 ≤ F2 + F4 during the process of rotating the screw valve to dispense the adhesive, the magnetic screw or insert has a magnetic attraction force that can offset the gravity of the iron oxide particles in the magnetic adhesive, eliminating the effect of the gravity of the iron oxide particles themselves on the control of the dispensing amount. Moreover, the action of the screw thrust stabilizes the dispensing of the magnetic adhesive, increasing the precision of control over the dispensing amount and enabling the dispensing of minute amounts of adhesive.

[0059] Furthermore, the magnetic attraction of the screw or insert can offset the effect of the gravity of the iron oxide particles themselves on the amount of dispensing, allowing for stable dispensing of minute amounts of adhesive. Conversely, without the magnetic attraction of the screw or insert, the iron oxide particles in the magnetic adhesive would cause the magnetic adhesive to have a high metal particle content and high density, resulting in low adhesive viscosity, and the amount of adhesive dispensed would increase significantly due to the gravity of the metal particles, resulting in an unstable dispense rate. The screw valve of the present application effectively avoids these problems, allowing for stable dispensing of minute amounts of adhesive.

[0060] When the adhesive discharge stops, the iron oxide particles in the magnetic adhesive can be attracted by the screw or insert due to the magnetic attraction of the screw or insert to the iron oxide particles in the magnetic adhesive. This prevents the magnetic adhesive from automatically leaking due to the presence of the iron oxide particles, allowing for quick discharge halt and preventing the magnetic adhesive from dripping or leaking.

[0061] In the description herein, references such as "one embodiment," "some embodiments," "exemplary embodiments," "examples," "particular examples," or "some examples" mean that the specific components, structures, materials, or features described in combination with the embodiment or example are included in at least one embodiment or example of the present application. In the description herein, the use of exemplary expressions for the above terms does not necessarily refer to the same embodiment or example. Furthermore, the specific components, structures, materials, or features described may be combined in any suitable manner in any one or more embodiments or examples.

[0062] Although the embodiments of the present application have been described and illustrated, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is limited by the claims and their equivalents. [Explanation of symbols]

[0063] 100 screw valve, 1 valve seat, 2 driver, 3 stator assembly, 4 screw, 5 insert, 6 needle, 7 fastener, 8 locking screw, 9 adhesive bucket, 10 stator, 11 liquid adhesive inlet, 12 spiral groove.

Claims

1. A valve seat (1), a driver (2) attached to the valve seat (1); a stator assembly (3) mounted on the valve seat (1) and having a liquid adhesive inlet (11) at its upper end; a screw (4) movably connected to the stator assembly (3), and power-transmittingly connected to the power output end of the driver (2) so that the screw itself is driven to rotate, the screw (4) having a spiral groove (12) communicating with the liquid adhesive inlet (11); a needle (6) located below the stator assembly (3) and connected to the stator assembly (3), the internal passage of which communicates with the spiral groove (12); The screw (4) or the stator assembly (3) is magnetic; When the magnetic adhesive flows through the spiral groove (12), the magnetic screw (4) or the stator assembly (3) has a magnetic attraction force to the iron oxide particles in the magnetic adhesive, which counteracts the gravity of the iron oxide particles in the magnetic adhesive. A screw valve (100) characterized by:

2. The stator assembly (3) comprises: a stator (10) attached to the valve seat (1), with the liquid adhesive inlet (11) at its upper end, and movably connected to the screw (4); a magnetic insert (5) disposed between the stator (10) and the screw (4), fixedly connected to the stator (10), and within which the screw (4) can rotate; 2. The screw valve (100) of claim 1.

3. A fastener (7) is provided at the lower end of the stator (10), A portion of the needle (6) is mounted within the fastener (7); The fastener (7) is fixedly connected to the stator (10).

3. The screw valve (100) according to claim 2.

4. 4. The screw valve (100) according to claim 3, characterized in that both the stator (10) and the fastener (7) are made of diamagnetic material.

5. The screw valve (100) according to any one of claims 2 to 4, characterized in that the outer surface of the insert (5) is a conical surface.

6. The stator (10) is provided with a locking screw (8), The locking screw (8) is screwed into the stator (10), The locking screw (8) abuts against the outer wall of the insert (5) to prevent the insert (5) from loosening. A screw valve (100) according to any one of claims 2 to 5.

7. A method for controlling adhesive discharge from a screw valve, comprising: The screw valve includes a driver, a stator assembly, a screw, a needle, and a fastener; the stator assembly includes a stator and an insert; a liquid adhesive inlet at an upper end of the stator assembly; the screw is provided with a helical groove communicating with the liquid adhesive inlet; The method for controlling adhesive dispensing comprises: Step S1 of magnetizing the screw or the insert to provide magnetism to the screw or the insert; Step S2: attaching the insert to the stator, then attaching the needle and the fastener to the lower end of the stator, and then further attaching the screw; and step S3, when applying with a dispenser, controlling the driver to drive the screw to rotate in the normal direction, thereby rotating the screw and simultaneously moving the magnetic adhesive in the spiral groove, where F1 is the magnetic attraction force of the screw or the insert to the iron oxide particles in the magnetic adhesive, F2 is the gravity of the iron oxide particles in the magnetic adhesive, F3 is the adhesive force of the liquid adhesive in the magnetic adhesive, and F4 is the thrust force on the magnetic adhesive when the screw is rotated, F1≧F2 and F1+F3≦F2+F4. A method for controlling adhesive discharge from a screw valve.

8. After step S3, The method further includes a step S4 in which, during the forward rotation period of the screw, the fluid pressure at the inlet of the liquid adhesive and the fluid pressure at the lower end of the spiral groove are controlled, and when the fluid pressure at the lower end of the spiral groove is Fa and the fluid pressure at the inlet of the liquid adhesive is Fb, both Fa and Fb are directed downward; By setting Fa≧Fb, the magnetic adhesive moves toward the lower end of the spiral groove due to the rotation of the screw and the action of the magnetic attraction force F1, and enters the needle from the lower end of the spiral groove, so that the discharge amount is stably controlled.

8. The method for controlling adhesive discharge from a screw valve according to claim 7.

9. After step S4, When the dispensing of adhesive by the screw stops, the screw is changed from a forward rotation state to a reverse rotation state, and when the reverse rotation time of the screw is t, the rotation of the screw is stopped after the reverse rotation time t of the screw has elapsed, and when the reverse rotation period and rotation of the screw have stopped, F2≦F1+F3 is satisfied in step S5, After the screw has stopped rotating during the reverse rotation period, the magnetic adhesive is attracted to the screw or the insert due to the magnetic attraction force F1 of the screw or the insert against the iron oxide particles in the magnetic adhesive.

9. The method for controlling adhesive discharge from a screw valve according to claim 8.

10. In step S1, a magnetic amount φ is applied to the screw or the insert, and φ is in a range of 5 mT≦φ≦300 mT.

10. The method for controlling adhesive discharge from a screw valve according to claim 7.

11. 11. The method for controlling adhesive discharge from a screw valve according to claim 7, wherein the rotation speed of the screw is v, and v≦300 rpm.

12. In step S5, the screw reversal time is 0.1 seconds ≦ t ≦ 0.6 seconds. The method for controlling adhesive discharge from a screw valve according to any one of claims 9 to 11.

13. The ratio of the fluid pressure Fa at the bottom end of the spiral groove to the fluid pressure Fb at the liquid adhesive inlet (11) is Fa / Fb=(1-5):1; The method for controlling adhesive discharge from a screw valve according to any one of claims 7 to 12.

14. In step S3, F2+F4-(F1+F3)≧F2; where F2 is the gravity of the iron oxide particles added to the magnetic adhesive and is known. The method for controlling adhesive discharge from a screw valve according to any one of claims 7 to 13.

15. In step S5, 0.5×F2≦F1+F3−F2≦F2 and F1+F3−F2≧Fa−Fb. The method for controlling adhesive discharge from a screw valve according to any one of claims 9 to 14.

16. In step S3, the thrust force F4 on the magnetic adhesive when the screw is rotated is expressed as F4=v×K, where v is the screw rotation speed and K is a constant. The method for controlling adhesive discharge from a screw valve according to any one of claims 7 to 15.

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