A piezoelectric injection valve

Abstract

The present invention relates to a piezoelectric injection valve, comprising a valve body, a valve seat and a striker, wherein the valve body and the valve seat are detachably fixed together, a piezoelectric drive mechanism is arranged in the valve body, the valve seat comprises a valve seat body and a nozzle, the valve seat body comprises a liquid storage cavity above the nozzle, the striker is installed in the valve body via a striker mounting seat, the upper end of the striker is drivingly connected to the piezoelectric drive mechanism, and the lower end cooperates with the nozzle, a pan-seal plug is installed in the opening of the striker mounting seat facing the liquid storage cavity, the pan-seal plug comprises an annular body and an elastic member, and is characterized in that the pan-seal plug further comprises a sealing ring, and the sealing ring seals the elastic member in the annular body. The piezoelectric injection valve of the present invention can greatly increase its service life, ensure production continuity, and reduce production and maintenance costs by changing the structure of the pan-seal plug.

Description

Technical Field

[0001] The invention relates to the field of glue dispensing equipment, and in particular to a piezoelectric injection valve for glue dispensing. Background Art

[0002] The piezoelectric injection valve utilizes the inverse piezoelectric effect of piezoelectric materials. It has a high injection frequency, a simple equipment structure, and can obtain very small glue dots by injection. On the other hand, the piezoelectric structure has high control accuracy, which can improve the quality of injection dispensing. The pan-seal plug is an important part of the piezoelectric injection valve, which is used to place glue into the valve body. During the use of the existing pan-seal plug, glue can easily enter the elastic part (spring or shrapnel), causing the elastic part to be stuck and unable to function normally, and then the pan-seal plug loses its sealing function, and finally may cause glue to enter the valve body, causing the piezoelectric injection valve to fail to work normally and have a short service life. This causes the dispensing quality to be unqualified and the defective rate to increase on the one hand, and on the other hand, it causes production interruptions and high production and maintenance costs. Summary of the invention

[0003] The present invention aims to provide a piezoelectric injection valve to solve the above problems. To this end, the specific technical solutions adopted by the present invention are as follows:

[0004] A piezoelectric injection valve comprises a valve body, a valve seat and a striker, wherein the valve body and the valve seat are detachably fixed together, a piezoelectric drive mechanism is arranged in the valve body, the valve seat comprises a valve seat body and a nozzle, the valve seat body comprises a liquid storage cavity above the nozzle, the striker is installed in the valve body through a striker mounting seat, the upper end of the striker mounting seat is drive-connected to the piezoelectric drive mechanism, and the lower end cooperates with the nozzle, a pan-seal plug is installed in the opening of the striker mounting seat toward the liquid storage cavity, the pan-seal plug comprises an annular body and an elastic member, and is characterized in that the pan-seal plug also comprises a sealing ring, which seals the elastic member in the annular body.

[0005] Furthermore, the valve seat body includes a nozzle mounting portion and a liquid inlet interface portion, the liquid storage cavity is located in the nozzle mounting portion, the liquid inlet interface portion has a flow channel, one end of the flow channel is connected to the liquid inlet joint, and the other end is connected to the liquid storage cavity.

[0006] Furthermore, the nozzle mounting portion and the liquid inlet interface portion are in a straight line or form an angle of 90 degrees.

[0007] Furthermore, the liquid inlet interface portion is also provided with a cleaning port, and the cleaning port is communicated with the flow channel and is sealed by a detachable plug.

[0008] Furthermore, the piezoelectric drive mechanism includes a piezoelectric block, a lever and a return spring. The piezoelectric block is installed obliquely above the striker, the short arm end of the lever is located below the piezoelectric block and the long arm end of the lever is located above the striker, so as to amplify the stroke of the piezoelectric block and transmit it to the striker. The return spring is sleeved on the striker, its upper end abuts the top of the striker, and its lower end abuts the striker mounting seat.

[0009] Furthermore, the piezoelectric injection valve is also provided with a micrometer head, the lower end of the micrometer head abuts against the top end of the striker to adjust the stroke of the striker.

[0010] Furthermore, the piezoelectric injection valve is also provided with a cooling device, and the cooling device is used to cool the piezoelectric block.

[0011] Furthermore, the piezoelectric injection valve is also provided with a counter, and the counter is used to display the accumulated number of actions of the piezoelectric block.

[0012] Furthermore, the piezoelectric injection valve is also provided with a heating device, which is installed around the valve seat and the hot-melt adhesive hose mounting seat, and the hot-melt adhesive hose mounting seat is fixedly connected to the valve seat.

[0013] Furthermore, the heating device includes a first heating part and a second heating part, the first heating part is used to heat the hot melt hose mounting seat, the second heating part is used to heat the valve seat, and the heating temperatures of the first heating part and the second heating part are controlled separately.

[0014] Furthermore, the annular body and the sealing ring of the pan seal are made of Teflon material.

[0015] The present invention adopts the above technical solution, which has the beneficial effect that the piezoelectric injection valve of the present invention can greatly increase its service life, ensure production continuity, and reduce production and maintenance costs by changing the structure of the pan-seal plug. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0017] Figure 1 is a perspective view of a piezoelectric injection valve according to an embodiment of the present invention;

[0018] Figure 2yes Figure 1 A front view of the piezoelectric injection valve shown with part of the housing removed;

[0019] Figure 3 yes Figure 2 A side view of the piezoelectric injection valve is shown;

[0020] Figure 4 is along Figure 3 A cross-sectional view of the piezoelectric injection valve taken along line AA;

[0021] Figure 5 yes Figure 3 An enlarged view of position B in FIG.

[0022] Figure 6 yes Figure 1 A perspective exploded view of the pan seal of the piezoelectric injection valve shown;

[0023] Figure 7 is a three-dimensional diagram of a piezoelectric injection valve according to another embodiment of the utility model;

[0024] Figure 8 yes Figure 7 A side view of a piezoelectric injection valve is shown. DETAILED DESCRIPTION

[0025] The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

[0026] like Figures 1 to 6As shown, a piezoelectric injection valve may include a valve body 1, a valve seat 2 and a striker 3, wherein the valve body 1 and the valve seat 2 are detachably fixed together, for example, by screws. A piezoelectric drive mechanism 11 and a control circuit board 12 are arranged in the valve body 1, wherein the control circuit board 12 is used to control the action of the piezoelectric drive mechanism 11 and is electrically connected to an electrical connector 13 arranged on the valve body 1. The structure of the piezoelectric drive mechanism is described below. The valve seat 2 includes a valve seat body 21 and a nozzle 22, wherein the valve seat body 21 has a liquid storage cavity 23 above the nozzle 22, and the striker 3 is installed in the valve body 1 through a striker mounting seat 4, wherein the upper end thereof is connected to the piezoelectric drive mechanism for driving, and the lower end thereof is matched with the nozzle, so that the glue in the liquid storage cavity 23 can be ejected from the nozzle under the action of the striker 3. A pan seal 5 is installed in the opening of the striker mounting seat 4 toward the liquid storage cavity 23, and the striker 3 is interference-fitted with the pan seal 5 to prevent glue from entering the valve body 1 from the liquid storage cavity 23. The pan-seal plug 5 includes an annular body 51, an elastic member 52 and a sealing ring 53, wherein the sealing ring 53 seals the elastic member 52 in the annular body 51. Compared with the existing pan-seal plug, the pan-seal plug 5 of the present invention has an additional sealing ring 53, so that glue does not enter the spring 52, thereby ensuring that the spring 52 will not be stuck, greatly improving the service life of the pan-seal plug 5. Preferably, the annular body 51 and the sealing ring 52 of the pan-seal plug 5 are both made of Teflon material to improve its wear resistance and further extend its service life.

[0027] In order to realize the active replacement of the pan-seal 5 and avoid its accidental damage that affects the continuity of production. The piezoelectric injection valve is also provided with a counter (not shown), which is used to display the number of times the current pan-seal is used and / or the cumulative number of actions of the piezoelectric block. When the number of times the current pan-seal is used is about to reach the rated number of times, an early warning signal is provided to remind the user to replace the pan-seal 5 in time, so as to achieve the purpose of active maintenance, ensure the continuity of production, and reduce costs. The counting signal of the counter can come from the control circuit board 12 of the piezoelectric block, or from a separately provided counting sensor.

[0028] like Figure 2 and 4As shown, the piezoelectric drive mechanism 11 may include a piezoelectric block 111, a lever 112 and a return spring 113. The piezoelectric block 111 is installed obliquely above the striker 3, the short arm end of the lever 112 is located below the piezoelectric block 111 and the long arm end is located above the striker 3, so as to amplify the stroke of the piezoelectric block 111 and transmit it to the striker 3, and the return spring 113 is sleeved on the striker 3, with its upper end abutting against the top of the striker 3 and its lower end abutting against the striker mounting seat 4. The specific working process of the piezoelectric drive mechanism is that the piezoelectric block 111 expands after being energized, and forms a thrust downward, and then the piezoelectric block 111 expands and displaces larger through the lever 112, and transmits the thrust to the striker 3, and the striker 3 moves downward, compressing the reset spring and driving the glue from the liquid storage cavity 23 into the nozzle 22, and then ejecting it from the nozzle 22; the piezoelectric block 111 retracts after being powered off, and the reset spring 113 resets the striker 3 to return to the initial position. The excitation voltage of the piezoelectric block 11 is a square wave, so the striker 3 reciprocates at high speed under the action of the piezoelectric drive mechanism, so that the glue is ejected from the nozzle 22. Preferably, the width of the square wave can be adjusted to facilitate the adjustment of the injection speed.

[0029] In order to prevent the piezoelectric block 11 from overheating, the piezoelectric injection valve is further provided with a cooling device (not shown), which is used to cool the piezoelectric block 11. The cooling device is usually water-cooled. Cooling water enters the installation cavity of the piezoelectric block 11 from the water inlet and then is discharged from the water outlet.

[0030] like Figure 2 and 4 As shown, the valve seat body 21 may include a nozzle mounting portion 211 and a liquid inlet interface portion 212, which may be formed integrally or separately and then assembled together. The liquid storage cavity 23 is located in the nozzle mounting portion 211, and the liquid inlet interface portion 212 has a flow channel 2121 in it, one end of the flow channel 2121 is connected to the liquid inlet connector 213, and the other end is connected to the liquid storage cavity 23. The liquid inlet connector 213 is used to connect the hose 100.

[0031] The nozzle mounting portion 211 and the liquid inlet interface portion 212 may be in a straight line (eg Figures 1 to 4 As shown) or form a 90 degree angle (as shown Figure 7 and 8 Therefore, the user can select valve seat bodies 21 of different configurations according to actual applications.

[0032] For easy cleaning, the liquid inlet interface portion 212 is further provided with a cleaning port 2122, which is communicated with the flow channel 2121 and sealed by a detachable plug 214. When cleaning is required, the plug 214 is removed and the flow channel 2121 and the nozzle 22 are cleaned with a cleaning agent.

[0033] In addition, the piezoelectric injection valve is also provided with a micrometer head 6, the lower end of which abuts against the top end of the striker 3, for adjusting the stroke of the striker 3, that is, adjusting the amount of glue dispensed. Therefore, the micrometer head 6 can achieve precise adjustment of the amount of glue dispensed.

[0034] In the case where the glue liquid to be sprayed is hot melt glue, that is, in the case where the hose 100 is a hot melt hose, the piezoelectric spray valve is further provided with a heating device (not shown), which is mounted around the valve seat 2 (specifically, the valve seat body 21) and the hot melt hose mounting seat (not shown), and the hot melt hose mounting seat is fixedly connected to the valve seat for placing the hot melt hose. Specifically, the heating device includes a first heating part and a second heating part, the first heating part is used to heat the hot melt hose mounting seat, and the second heating part is used to heat the valve seat, and the heating temperatures of the first heating part and the second heating part are controlled separately.

[0035] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A piezoelectric injection valve, comprising a valve body, a valve seat and a striker, wherein the valve body and the valve seat are detachably fixed together, a piezoelectric drive mechanism is arranged in the valve body, the valve seat comprises a valve seat body and a nozzle, the valve seat body comprises a liquid storage cavity above the nozzle, the striker is installed in the valve body through a striker mounting seat, the upper end of the striker is drivingly connected to the piezoelectric drive mechanism, and the lower end cooperates with the nozzle, a pan-seal plug is installed in the opening of the striker mounting seat facing the liquid storage cavity, the pan-seal plug comprises an annular body and an elastic member, and is characterized in that: The pan-seal plug also includes a sealing ring, which seals the elastic member in the annular body, so that the glue in the liquid storage cavity does not enter the annular body, and ensures that the elastic member is not stuck by the glue, thereby increasing the service life of the pan-seal plug; The piezoelectric injection valve is also provided with a counter, which is used to display the number of times the current flood seal is used and / or the cumulative number of times the piezoelectric block is actuated.

2. The piezoelectric injection valve according to claim 1, characterized in that The valve seat body includes a nozzle mounting part and a liquid inlet interface part, the liquid storage cavity is located in the nozzle mounting part, and a flow channel is provided in the liquid inlet interface part, one end of the flow channel is connected to the liquid inlet joint, and the other end is connected to the liquid storage cavity.

3. The piezoelectric injection valve according to claim 2, characterized in that The nozzle mounting portion and the liquid inlet interface portion are in a straight line or form a 90 degree angle.

4. The piezoelectric injection valve according to claim 2, characterized in that The liquid inlet interface portion is also provided with a cleaning port, which is communicated with the flow channel and is sealed by a detachable plug.

5. The piezoelectric injection valve according to claim 1, characterized in that The piezoelectric drive mechanism includes a piezoelectric block, a lever and a return spring. The piezoelectric block is installed obliquely above the striker, the short arm end of the lever is located below the piezoelectric block and the long arm end of the lever is located above the striker, and the return spring is sleeved on the striker, with its upper end abutting the top of the striker and its lower end abutting the striker mounting seat.

6. The piezoelectric injection valve according to claim 1, characterized in that The piezoelectric injection valve is also provided with a micrometer head, the lower end of which abuts against the top end of the striker to adjust the stroke of the striker.

7. The piezoelectric injection valve according to claim 5, characterized in that The piezoelectric injection valve is further provided with a cooling device, and the cooling device is used to cool the piezoelectric block.

8. The piezoelectric injection valve according to claim 1, characterized in that The piezoelectric injection valve is also provided with a heating device, which is circumferentially mounted on the valve seat and the hot melt hose mounting seat, and the hot melt hose mounting seat is fixedly connected to the valve seat.

9. The piezoelectric injection valve according to claim 8, characterized in that The heating device includes a first heating part and a second heating part, the first heating part is used to heat the hot melt hose mounting seat, the second heating part is used to heat the valve seat, and the heating temperatures of the first heating part and the second heating part are controlled separately.

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