Piezoelectric injection valve and glue injection apparatus

Abstract

The utility model discloses a piezoelectric injection valve and glue spraying equipment relates to point gum device technical field, wherein, piezoelectric injection valve includes valve body, movable injection device and check valve subassembly, check valve subassembly includes setting on the first drive piece of valve body, first piezoelectric ceramic element, first displacement amplification mechanism and valve needle, first drive piece is connected with first piezoelectric ceramic element drive, first displacement amplification mechanism is connected between first piezoelectric ceramic element and valve needle, and valve needle is inserted in the accommodating cavity correspondingly and can move along its axial direction, to make valve needle have the first position of the fluid transmission channel of on -off and the second position of the fluid transmission channel of blocking. The utility model provides technical scheme to drive first piezoelectric ceramic element through first drive piece, and through first displacement amplification mechanism drive valve needle and move along its axial direction to on -off or block the fluid transmission channel, to improve the consistency of piezoelectric injection valve injection.

Description

Technical Field

[0001] This utility model relates to the field of dispensing device technology, and in particular to a piezoelectric jet valve and a glue spraying device. Background Technology

[0002] Piezoelectric jet valves are widely used for controllable flow and high-speed dispensing of various adhesives, including surface mount adhesives, conductive silver pastes, underfill adhesives, sealants, and surface coating adhesives. The adhesive cartridge is clamped onto the piezoelectric jet valve to spray the adhesive from the cartridge to the target location.

[0003] Traditional piezoelectric jet valves utilize the length changes of piezoelectric ceramics to drive levers during dispensing, enabling high-frequency action of the ejector pin. However, the fluid properties and compressibility of the adhesive lead to unstable dispensing volume, and adhesive may backflow during dispensing, affecting the consistency of the dispensing amount. Utility Model Content

[0004] The main purpose of this invention is to provide a piezoelectric jet valve and a glue spraying device, which aims to improve the consistency of glue dispensing by the piezoelectric jet valve.

[0005] To achieve the above objectives, the present invention proposes a piezoelectric injection valve for installing a liquid storage tank and injecting fluid from the liquid storage tank. The piezoelectric injection valve includes: The valve body has a receiving cavity and an inlet and an outlet communicating with the receiving cavity. A fluid transmission channel and an outlet communicating with the fluid transmission channel are formed in the receiving cavity. The two ends of the fluid transmission channel are respectively connected to the inlet and the outlet. A movable spraying device is located on the valve body and movably seals the liquid outlet; and The check valve assembly includes a first drive member, a first piezoelectric ceramic element, a first displacement amplification mechanism, and a valve needle disposed on the valve body. The first drive member is drivenly connected to the first piezoelectric ceramic element, and the first displacement amplification mechanism is connected between the first piezoelectric ceramic element and the valve needle. The valve needle is inserted into the receiving cavity corresponding to the through-hole and can move axially thereto, so that the valve needle has a first position that opens the fluid transmission channel and a second position that blocks the fluid transmission channel.

[0006] In one embodiment, the valve body has a first receiving groove, the first drive member and the first rotating shaft are connected to the first groove sidewall of the first receiving groove, the first piezoelectric ceramic element includes a first ceramic strip and a second ceramic strip that are intersected and connected, the first ceramic strip is movably connected to the groove sidewall of the first receiving groove and abuts against the first drive member and the first rotating shaft, the second ceramic strip is disposed in the first receiving groove, one end of the second ceramic strip abuts against the side of the first ceramic strip opposite to the first rotating shaft corresponding to the first rotating shaft, and the other end movably abuts against the first displacement amplification mechanism.

[0007] In one embodiment, the second sidewall of the first receiving groove is provided with a second rotating shaft, the second sidewall of the groove is disposed opposite to the first sidewall of the groove, and the first displacement amplification mechanism includes a first connecting rod, one end of the first connecting rod abuts against the second rotating shaft on the side away from the second ceramic strip, and the other end is drivenly connected to the valve needle.

[0008] In one embodiment, the third groove sidewall of the first receiving groove is provided with a third rotating shaft, the third groove sidewall and the second groove sidewall form a stepped structure, the first displacement amplification mechanism further includes a second connecting rod, one end of the second connecting rod abuts against the third rotating shaft, and movably abuts against the first connecting rod on the side opposite to the third rotating shaft, the other end of the second connecting rod abuts against the valve needle.

[0009] In one embodiment, the fluid transmission channel includes two spaced-apart transmission sections, the gap between the two transmission sections forming the through port, and the valve needle forming a liquid passage. At the first position, the liquid passage is connected to the two transmission sections respectively, and at the second position, the ports of the two transmission sections at their closest ends are positioned opposite to the outer peripheral wall of the valve needle.

[0010] In one embodiment, there is a gap between the ports of the two transmission segments at their closest points to each other and the valve needle.

[0011] In one embodiment, the two transmission segments are configured as a first transmission segment connecting the liquid inlet and a second transmission segment connecting the liquid outlet, wherein the length of the second transmission segment is less than or equal to the length of the first transmission segment.

[0012] In one embodiment, the piezoelectric injection valve further includes a sealing element disposed within the receiving cavity, the sealing element being connected to the inner wall surface of the receiving cavity and sleeved on the outer side of the valve needle, the inner peripheral wall of the sealing element having a lip that abuts against the valve needle.

[0013] In one embodiment, the valve body forms a second receiving groove, and the movable injection device includes a second driving member, a second piezoelectric ceramic element, a third connecting rod, and a striking pin assembly. The second driving member is connected to the side wall of the second receiving groove, the second piezoelectric ceramic element is movably connected to the side wall of the second receiving groove and abuts against the second driving member, the third connecting rod is disposed in the second receiving groove and connects between the second piezoelectric ceramic element and the striking pin assembly, and one end of the striking pin assembly facing away from the third connecting rod passes through the fluid transmission channel and movably seals the liquid outlet.

[0014] In one embodiment, the valve body includes a first housing, a second housing, and a third housing connected to each other. The first housing and the second housing are disposed opposite to each other. The outer side walls of the first housing and the second housing are provided with fixing members for fixing the liquid storage cylinder. A first receiving groove is formed on the side of the first housing away from the second housing, and the check valve assembly is at least partially located in the first receiving groove. A second receiving groove is formed on the side of the second housing away from the first housing, and the movable injection device is at least partially located in the second receiving groove. The fluid transmission channel is formed inside the third shell. The first shell and the second shell are located on the same side of the third shell. The liquid outlet is formed on the side of the third shell away from the second shell, and the liquid inlet is formed on the side of the first shell away from the second shell. The valve needle passes through the third shell and is movably connected to the first shell.

[0015] This utility model also proposes a glue spraying device, including the aforementioned piezoelectric spray valve.

[0016] The technical solution of this utility model uses a first driving component to drive a first piezoelectric ceramic element, and a first displacement amplification mechanism to drive a valve needle to move axially along the element. This allows the valve needle to open the fluid transmission channel at a first position and block the fluid transmission channel at a second position. When the piezoelectric injection valve performs injection operations, the valve needle is located at the second position, blocking the fluid transmission channel, thereby blocking the fluid backflow path. This effectively reduces fluid backflow and compression phenomena, and helps avoid pressure fluctuations and unstable liquid output caused by fluid compressibility or fluidity. Consequently, it improves the consistency and accuracy of the piezoelectric injection valve during injection.

[0017] Meanwhile, the first piezoelectric ceramic element generates a high-frequency micro-deformation, which is amplified by the first displacement amplification mechanism and transmitted to the valve needle, thereby realizing high-frequency drive of the valve needle. This ensures that the valve needle can block the fluid transmission channel in time every time the piezoelectric injection valve injects, thus ensuring the consistency and accuracy of the piezoelectric injection valve during injection. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the structure of an embodiment of the piezoelectric injection valve provided by this utility model; Figure 2 for Figure 1 Front view of the piezoelectric injection valve in the image; Figure 3 for Figure 1 A schematic diagram of the piezoelectric injection valve from another perspective; Figure 4 for Figure 3 A partial cross-sectional view of the piezoelectric injection valve in the image; Figure 5 This is a partial schematic diagram of the piezoelectric injection valve when the valve needle is in the first position; Figure 6 This is a partial schematic diagram of the piezoelectric injection valve when the valve needle is in the second position; Figure 7 for Figure 3 A partial cross-sectional view of the piezoelectric injection valve in the image.

[0020] Explanation of icon numbers: 10. Piezoelectric injection valve; 20. Liquid reservoir; 100. Valve body; 200. Movable injection device; 300. Check valve assembly; 400. Seal; 500. Heat sink; 600. Fixing component; 110. First housing; 111. First receiving groove; 1111. First groove sidewall; 1112. Second groove sidewall; 1113. Third groove sidewall; 120. Second housing; 121. Second receiving groove; 130. Third housing; 131. Receiving cavity; 132. Fluid transmission channel; 1321. First transmission section; 1322. Second transmission section 133. Inlet; 134. Outlet; 210. Second drive unit; 220. Second piezoelectric ceramic element; 230. Impact pin assembly; 240. Third connecting rod; 310. Valve needle; 311. Liquid passage; 320. First drive unit; 330. First piezoelectric ceramic element; 331. First ceramic strip; 332. Second ceramic strip; 340. First displacement amplification mechanism; 341. First connecting rod; 342. Second connecting rod; 351. First rotating shaft; 352. Second rotating shaft; 353. Third rotating shaft; 410. Lip.

[0021] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0023] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0024] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0025] This utility model proposes a piezoelectric injection valve.

[0026] Please see Figure 1 , Figure 3 and Figure 4In one embodiment of this utility model, the piezoelectric jet valve 10 is used to install a liquid storage tank 20 and jet the fluid inside the liquid storage tank 20. The piezoelectric jet valve 10 includes a valve body 100, a movable jetting device 200, and a check valve assembly 300. The valve body 100 forms a receiving cavity 131 and an inlet 133 and an outlet 134 communicating with the receiving cavity 131. A fluid transmission channel 132 and an outlet communicating with the fluid transmission channel 132 are formed inside the receiving cavity 131. The two ends of the fluid transmission channel 132 are respectively connected to the inlet 133 and the outlet 134. The movable jetting device 200 is disposed on the valve body 100 and is movable. The check valve assembly 300 includes a first drive member 320, a first piezoelectric ceramic element 330, a first displacement amplification mechanism 340, and a valve needle 310, all disposed on the valve body 100. The first drive member 320 is driven to connect with the first piezoelectric ceramic element 330. The first displacement amplification mechanism 340 is connected between the first piezoelectric ceramic element 330 and the valve needle 310. The valve needle 310 is inserted into the receiving cavity 131 through the corresponding opening and can move along its axial direction, so that the valve needle 310 has a first position that opens the fluid transmission channel 132 and a second position that blocks the fluid transmission channel 132.

[0027] Specifically, a fixing member 600 is provided on the outer wall of the valve body 100 for installing the liquid storage cylinder 20. The fixing member 600 has an arc-shaped groove with an opening. When installing the liquid storage cylinder 20, the liquid storage cylinder 20 is clamped into the arc-shaped groove of the fixing member 600 through the opening, thereby fixing the liquid storage cylinder 20. The opening on the fixing member 600 facilitates the replacement and installation of the liquid storage cylinder 20. A receiving cavity 131 is formed inside the valve body 100, and a fluid transmission channel 132 for fluid flow is formed inside the receiving cavity 131. The ends of both ends of the valve body 100 have inlet ports 133 and outlet ports connected to the fluid transmission channel 132. The opening of the liquid storage cylinder 20 is connected to the inlet port 133. Under the squeezing action of the extruder, the fluid in the storage cylinder 20 flows into the fluid transmission channel 132 through the inlet 133 along the cylinder opening of the storage cylinder 20, and flows along the fluid transmission channel 132 towards the outlet 134.

[0028] The movable spraying device 200 is located within the valve body 100 and is movably sealed at the outlet 134 to open and close the outlet 134, controlling the spraying of fluid. By aligning the outlet 134 with the target position to be sprayed, fluid is sprayed along the outlet 134 to the target position. By setting the movable spraying device 200 to movably seal the outlet 134, the extruder and the movable spraying device 200 work simultaneously, so that each time the movable spraying device 200 moves, a certain amount of fluid is sprayed from the outlet 134. During the fluid spraying process, the movable spraying device 200 moves at high speed and controls the overall movement of the piezoelectric spray valve 10, thus connecting the point-like fluid sprays from the outlet 134 into a line to complete the operation at the target position. The fluid can specifically be conductive silver paste, various adhesives, or other liquids requiring spraying operations. For example, for adhesives, connecting the adhesive dots sprayed from the outlet 134 into a line completes the adhesive spraying at the target position.

[0029] Because fluids possess a certain degree of compressibility and fluidity, backflow can easily occur during injection, leading to unstable output. This invention addresses this by incorporating a check valve assembly 300, which blocks the backflow path during injection, effectively reducing fluid backflow and compression. This ensures a more consistent pressure state for the fluid during each injection, thereby guaranteeing consistent output. Even with complex fluids possessing certain viscosity and compressibility, such as conductive silver paste and underfill adhesives, it maintains excellent injection performance. The piezoelectric injection valve 10 is particularly suitable for industrial applications requiring high precision and stability, such as electronic packaging and chip bonding.

[0030] The opening can be an opening on one side wall of the fluid transmission channel 132 or a channel section of the fluid transmission channel 132, for the valve needle 310 of the check valve assembly 300 to pass through, so that the valve needle 310 can move along its axial direction, thereby opening or blocking the fluid transmission channel 132.

[0031] The valve needle 310 has a cylindrical or conical structure and is movable along its axial direction, thus having a first position and a second position. (See also...) Figure 5 When the movable injection device 200 raises to allow liquid inflow, the valve needle 310 moves to the first position, and the check valve assembly 300 opens the fluid transmission channel 132, allowing the fluid in the storage tank 20 to smoothly reach the outlet 134 through the fluid transmission channel 132; please refer to Figure 6When the active injection device 200 presses down to discharge liquid, the valve needle 310 moves to the second position, and the check valve assembly 300 blocks the fluid transmission channel 132. Fluid near the outlet 134 cannot flow back towards the inlet 133 through the fluid transmission channel 132. Simultaneously, because the valve needle 310 blocks the fluid transmission channel 132, the space at the end of the fluid transmission channel 132 near the outlet 134 is reduced. The fluid near the outlet 134 is confined to a small volume space. Even if the fluid is compressed, its impact is limited to a localized area, reducing overall pressure fluctuations. Therefore, by setting the check valve assembly 300 to block or open the fluid transmission channel 132, it is beneficial to avoid pressure fluctuations and unstable discharge caused by the compressibility or fluidity of the fluid, thereby improving the consistency of the piezoelectric injection valve 10 during injection and increasing the accuracy of the fluid discharge volume.

[0032] The first driving element 320 is mounted on the valve body 100 and electrically connected to an external control circuit. The first driving element 320 is driven by the first piezoelectric ceramic element 330 and applies a driving voltage to it. Utilizing the piezoelectric effect, the first piezoelectric ceramic element 330 undergoes a minute length change under voltage drive, which is transmitted to the first displacement amplification mechanism 340. The first displacement amplification mechanism 340 amplifies the minute displacement of the first piezoelectric ceramic element 330 to drive the valve needle 310 to move axially, thereby switching to either a first position that opens the fluid transmission channel 132 or a second position that blocks the fluid transmission channel 132. By controlling the on / off state of the first piezoelectric ceramic element 330, precise control of the fluid transmission channel 132 by the valve needle 310 can be achieved. This allows for rapid blocking of the fluid transmission channel 132 during injection by the piezoelectric injection valve 10, preventing fluid backflow, ensuring consistent fluid volume in each injection, and improving injection consistency and accuracy. In addition, piezoelectric ceramic elements have fast response speed and high control precision. Combined with the first displacement amplification mechanism 340, they can realize high-frequency spraying operation, which is especially suitable for high-speed automated production scenarios, such as electronic packaging, chip packaging, and surface mount production scenarios with high requirements for dispensing accuracy and frequency.

[0033] Understandably, the deformation of the first piezoelectric ceramic element 330 is linearly related to the applied voltage, allowing precise control of the valve needle 310's displacement via voltage, thereby achieving micron-level or even sub-micron-level flow control. Combined with the first displacement amplification mechanism 340, the valve needle 310 can perform hundreds to thousands of opening and closing actions per second, meeting the demands of high-speed injection and ensuring that the valve needle 310 promptly blocks the fluid transmission channel 132 each time the piezoelectric injection valve 10 injects. Furthermore, this driving method eliminates the need for traditional electromagnetic or pneumatic actuators, resulting in a more compact structure and the absence of frictional wear parts, making it suitable for long-term continuous operation.

[0034] The first displacement amplification mechanism 340 can adopt a lever-type, bridge-type, or flexible hinge-type structure, and its amplification ratio can be designed according to actual needs to meet the injection frequency and stroke requirements under different working conditions.

[0035] The technical solution of this utility model uses a first driving member 320 to drive a first piezoelectric ceramic element 330, and a first displacement amplification mechanism 340 to drive a valve needle 310 to move axially. This allows the valve needle 310 to open the fluid transmission channel 132 in a first position and block the fluid transmission channel 132 in a second position. When the piezoelectric injection valve 10 performs injection operations, the valve needle 310 is located in the second position blocking the fluid transmission channel 132, thereby blocking the fluid backflow path, effectively reducing fluid backflow and compression phenomena, and helping to avoid pressure fluctuations and unstable liquid output caused by fluid compressibility or fluidity. This improves the consistency and accuracy of the piezoelectric injection valve 10 during injection.

[0036] Meanwhile, the first piezoelectric ceramic element 330 generates a high-frequency micro-deformation, which is amplified by the first displacement amplification mechanism 340 and transmitted to the valve needle 310, thereby realizing high-frequency drive of the valve needle 310. This ensures that the valve needle 310 can block the fluid transmission channel 132 in time every time the piezoelectric injection valve 10 injects, thus ensuring the consistency and accuracy of the injection of the piezoelectric injection valve 10.

[0037] In one implementation, please refer to Figure 1 and Figure 2 The valve body 100 has a first receiving groove 111. The first groove sidewall 1111 of the first receiving groove 111 is connected to the first driving member 320 and the first rotating shaft 351. The first piezoelectric ceramic element 330 includes a first ceramic strip 331 and a second ceramic strip 332 that are intersected and connected. The first ceramic strip 331 is movably connected to the groove sidewall of the first receiving groove 111 and abuts against the first driving member 320 and the first rotating shaft 351. The second ceramic strip 332 is disposed in the first receiving groove 111. One end of the second ceramic strip 332 abuts against the side of the first ceramic strip 331 opposite to the first rotating shaft 351, and the other end movably abuts against the first displacement amplification mechanism 340.

[0038] The valve body 100 is provided with a first receiving groove 111, and the first groove sidewall 1111 of the first receiving groove 111 is connected to a first driving member 320 and a first rotating shaft 351. The first ceramic strip 331 and the second ceramic strip 332 are intersecting and connected, and can be in a "T" shape or an "L" shape. When the first driving member 320 applies voltage to the first ceramic strip 331, the first ceramic strip 331 undergoes a slight deformation, swinging or bending around the first rotating shaft 351, thereby pushing the second ceramic strip 332. The other end of the second ceramic strip 332 transmits this displacement to the first displacement amplification mechanism 340, which ultimately drives the valve needle 310 to perform a high-frequency opening and closing action.

[0039] Understandably, after the first driving component 320 is connected to the external circuit, it drives the first ceramic strip 331 to swing around the first rotating shaft 351, which in turn causes the second ceramic strip 332 to tilt. The tilted second ceramic strip 332 presses against the first displacement amplification mechanism 340, which in turn causes the first displacement amplification mechanism 340 to press against the valve needle 310. This causes the valve needle 310 to block the outlet during its movement, thus opening and closing the outlet. The valve needle 310, in conjunction with the opening and closing of the liquid outlet 134, either opens or blocks the fluid transmission channel 132. The valve needle 310 is fitted with an elastic element (not shown in the figure) on its outer periphery. One end of the elastic element abuts against the side wall of the first receiving groove 111, and the other end abuts against the first displacement amplification mechanism 340. The elastic element is used to drive the first displacement amplification mechanism 340 to return to its initial position through the elastic force of the spring. Then, the first displacement amplification mechanism 340 drives the second ceramic strip 332 to return to its initial position. In turn, the second ceramic strip 332 drives the first ceramic strip 331 to return to its initial position and abut against the first driving member 320. The first driving member 320 then drives the first ceramic strip 331 to perform the next movement.

[0040] In other embodiments, only one ceramic strip may be provided, with one end of the ceramic strip abutting against the first driving member 320 and the other end movably abutting against the first displacement amplification mechanism 340.

[0041] In one implementation, please refer to Figure 1 and Figure 2 The second groove sidewall 1112 of the first receiving groove 111 is provided with a second rotating shaft 352. The second groove sidewall 1112 is arranged opposite to the first groove sidewall 1111. The first displacement amplification mechanism 340 includes a first connecting rod 341. One end of the first connecting rod 341 abuts against the second rotating shaft 352 on the side away from the second ceramic strip 332, and the other end is connected to the valve needle 310.

[0042] The first receiving groove 111 has a first groove sidewall 1111 and a second groove sidewall 1112 arranged opposite to each other. The second rotating shaft 352 is disposed on the second groove sidewall 1112. The second ceramic strip 332 extends approximately along the distribution direction of the first groove sidewall 1111 and the second groove sidewall 1112. The first displacement amplification mechanism 340 includes a first connecting rod 341. The first connecting rod 341 swings around the second rotating shaft 352 under the action of the second ceramic strip 332. The first connecting rod 341, the first piezoelectric ceramic element 330, and the second rotating shaft 352 together constitute a lever-type displacement amplification system, which geometrically amplifies the small deformation of the piezoelectric ceramic, thereby driving the valve needle 310 to move effectively.

[0043] Understandably, when the first ceramic strip 331 deforms under the action of the first driving member 320, it causes the second ceramic strip 332 to undergo displacement, which in turn pushes the first connecting rod 341 to rotate around the second rotating shaft 352. The other end of the first connecting rod 341 transmits the amplified displacement to the valve needle 310, causing the valve needle 310 to move axially, thereby opening or closing the fluid channel. In this way, the tiny driving displacement of the first piezoelectric ceramic can be amplified many times through the lever principle to meet the large stroke action requirements of the valve needle 310, thereby driving the valve needle 310 to perform high-frequency, high-precision opening and closing actions.

[0044] In other embodiments, the first displacement amplification mechanism 340 may also adopt a bridge-type or flexible hinge-type structure.

[0045] In one implementation, please refer to Figure 1 and Figure 2 The third groove sidewall 1113 of the first receiving groove 111 is provided with a third rotating shaft 353. The third groove sidewall 1113 and the second groove sidewall 1112 form a stepped structure. The first displacement amplification mechanism 340 also includes a second connecting rod 342. One end of the second connecting rod 342 abuts against the third rotating shaft 353 and moves against the first connecting rod 341 on the side away from the third rotating shaft 353. The other end of the second connecting rod 342 abuts against the valve needle 310.

[0046] The second slot sidewall 1112 and the third slot sidewall 1113 are located on the same side of the first piezoelectric ceramic element 330. Compared to the second slot sidewall 1112, the plane containing the third slot sidewall 1113 is farther from the plane containing the first slot sidewall 1111, thus forming a stepped structure between the third slot sidewall 1113 and the second slot sidewall 1112. In this way, one end of the first connecting rod 341 is movably connected to the second slot sidewall 1112 via the second rotating shaft 352, and the other end is connected to the upper surface of the second connecting rod 342. The third rotating shaft 353 is mounted on the third slot sidewall 1113, serving as the rotation fulcrum and support point of the second connecting rod 342. The first connecting rod 341 and the second connecting rod 342 constitute a stepped, multi-stage linkage amplification mechanism. Through the linkage between the first link 341 and the second link 342, multi-stage lever amplification is achieved, thereby gradually amplifying the minute displacement of the first piezoelectric ceramic element 330, and finally driving the valve needle 310 to perform high-precision, long-stroke motion control.

[0047] Understandably, when the first piezoelectric ceramic element 330 deforms under the voltage of the first driving member 320, the second ceramic strip 332 pushes the first connecting rod 341 to move around the second rotating shaft 352. The first connecting rod 341 amplifies the minute displacement of the first piezoelectric ceramic element 330 for the first time. At the same time, the first connecting rod 341 drives the second connecting rod 342 to move around the third rotating shaft 353. The second connecting rod 342 amplifies the displacement again and transmits it to the valve needle 310. Through the linkage of the first connecting rod 341 and the second connecting rod 342, the minute driving displacement of the first piezoelectric ceramic element 330 is amplified in multiple stages, thereby meeting the high-frequency, long-stroke, and high-precision motion control required by the valve needle 310 during the injection process.

[0048] In other embodiments, depending on the required stroke of the valve needle 310 of the piezoelectric injection valve 10 of different specifications, only the first connecting rod 341 can be provided. One end of the first connecting rod 341 is connected to the second ceramic strip 332, and the other end is directly connected to the valve needle 310. Alternatively, two or more connecting rods can be provided to achieve more levels of displacement amplification.

[0049] In one embodiment, the fluid transmission channel 132 includes two spaced transmission sections, with the gap between the two transmission sections forming an opening. The valve needle 310 forms a liquid passage 311. In a first position, the liquid passage 311 is connected to the two transmission sections respectively. In a second position, the ports of the two transmission sections at their closest ends are positioned opposite to the outer peripheral wall of the valve needle 310.

[0050] The gap between the two transmission sections forms an orifice, one located upstream and the other downstream. This orifice serves as the movement space for the valve needle 310, allowing it to move axially to control the flow of fluid. The valve needle 310 internally contains a fluid passage 311; please refer to [reference needed]. Figure 5When the valve needle 310 moves to the first position, the liquid passage 311 aligns with the ports of the two transmission sections closest to each other, thus connecting the two transmission sections. The fluid flows sequentially along the path of the storage tank 20, inlet 133, upstream transmission section (i.e., first transmission section 1321), liquid passage 311, downstream transmission section (i.e., second transmission section 1322), and outlet 134. Please refer to [link / reference]. Figure 6 When the valve needle 310 moves to the second position, the ports of the two transmission sections at their closest ends are offset from the liquid passage 311 and are opposite to the outer peripheral wall of the valve needle 310, so as to block the connection between the two transmission sections. The fluid at the outlet 134 cannot flow back to the inlet 133 side, avoiding backflow and flow fluctuation caused by fluid compressibility. The fluid can only be ejected at high speed from the outlet 134 to complete the dispensing or spraying operation and ensure stable spraying.

[0051] In other embodiments, the port is an opening formed on one side wall of the fluid transmission channel 132. When the valve needle 310 moves to the second position, the valve needle 310 is inserted into the fluid transmission channel 132 from the port and abuts against the other side wall opposite to the port to block the flow path of the fluid. When the valve needle 310 moves to the first position, there is a gap between the other side wall opposite to the port and the valve needle 310, and the fluid can flow from the gap to the outlet 134.

[0052] In one embodiment, there is a gap between the ports of the two transmission segments at their respective ends and the valve needle 310.

[0053] During the movement of the valve needle 310, the gap prevents the valve needle 310 from directly and rigidly contacting the transmission section port, reducing the risk of wear and jamming, ensuring the valve needle 310 operates flexibly and reliably, and improving the stability and durability of the valve needle 310 during long-term use. Moreover, the existence of a small gap allows for a certain degree of tolerance, reducing manufacturing costs and difficulty.

[0054] It is worth mentioning that the gap between the valve needle 310 and the transmission section is very small, much smaller than the effective flow channel for fluid. When the valve needle 310 is in the first position, the fluid flow velocity is very high, and this gap does not affect the connectivity of the fluid passage 311; the fluid can still pass smoothly through the fluid transmission channel 132. When the valve needle 310 is in the second position, during the injection process, due to the high-speed compression of the fluid by the movable injection device 200, the resistance of the fluid passing through this tiny gap is extremely high, almost equivalent to being blocked. This allows for a good anti-backflow effect even without complete sealing.

[0055] In other embodiments, there may be no gap between the ports of the two transmission segments at their respective ends and the valve needle 310, and the end faces of the ports may fit against the outer peripheral wall of the valve needle 310, and both may be coated with a wear-resistant coating, a smooth coating, etc.

[0056] In one implementation, please refer to Figure 4 The two transmission segments are configured as a first transmission segment 1321 connecting the liquid inlet 133 and a second transmission segment 1322 connecting the liquid outlet 134, wherein the length of the second transmission segment 1322 is less than or equal to the length of the first transmission segment 1321.

[0057] The first transmission section 1321 is the channel from the inlet 133 to the outlet, and the second transmission section 1322 is the channel from the outlet to the outlet 134. The lengths of the first transmission section 1321 and the second transmission section 1322 can be the same, or the first transmission section 1321 can be relatively longer and the second transmission section 1322 relatively shorter. The longer first transmission section 1321 helps maintain the stability of fluid input. The shorter second transmission section 1322 reduces the volume change of the fluid under pressure, weakens the impact of pressure fluctuations on the spray volume, reduces spraying errors caused by fluid compressibility, and improves dispensing accuracy. The check valve assembly 300 only needs to block the fluid in a small space, resulting in a faster response and better effect. The fluid is more easily propelled out by the movable spray device 200, which helps to achieve high-speed, high-frequency operations.

[0058] In other embodiments, the length of the second transmission segment 1322 may be greater than the length of the first transmission segment 1321, and the outlet may be located closer to the midpoint of the fluid transmission channel 132.

[0059] In one implementation, please refer to Figures 5 to 7 The piezoelectric injection valve 10 also includes a sealing element 400 disposed in the receiving cavity 131. The sealing element 400 is connected to the inner wall surface of the receiving cavity 131 and is sleeved on the outer side of the valve needle 310. The inner peripheral wall of the sealing element 400 has a lip 410 that abuts against the valve needle 310.

[0060] A fluid transmission pipe is installed inside the receiving cavity 131, forming a fluid transmission channel 132; or the fluid transmission channel 132 is integrally formed by the valve body 100; of course, in other embodiments, the valve body 100 may form only a cavity, which serves as the fluid transmission channel 132 and is equipped with a one-way valve. The valve needle 310 passes through the receiving cavity 131 and moves at the opening of the fluid transmission channel 132, and a small amount of fluid may flow into the receiving cavity 131 from the opening. By providing a sealing element 400, fluid leakage from the gap between the valve needle 310 and the valve body 100 can be prevented. The sealing element 400 is disposed inside the receiving cavity 131 and connected to the inner wall surface of the receiving cavity 131, and surrounds the valve needle 310. The inner peripheral wall of the sealing element 400 is provided with a lip 410. During injection, the valve needle 310 moves axially. Throughout this process, the lip 410 of the sealing element 400 remains in contact with the outer peripheral wall of the valve needle 310, forming a dynamic seal. The lip 410 has a certain elastic deformation capacity, allowing it to deform slightly with the axial movement of the valve needle 310, ensuring good sealing performance even during high-speed reciprocating motion. The sealing element 400 and the lip 410 are integrally molded and can be made of corrosion-resistant and wear-resistant elastic materials (such as fluororubber or silicone) to extend their service life.

[0061] In other embodiments, the check valves are all located in the receiving cavity 131, the valve needle 310 does not need to pass through the valve body 100, and there is no gap between the valve needle 310 and the valve body 100, so there is no need to provide a sealing element 400.

[0062] In one implementation, please refer to Figure 3 The valve body 100 has a second receiving groove 121. The movable injection device 200 includes a second driving member 210, a second piezoelectric ceramic element 220, a third connecting rod 240, and a striker assembly 230. The second driving member 210 is connected to the side wall of the second receiving groove 121. The second piezoelectric ceramic element 220 is movably connected to the side wall of the second receiving groove 121 and abuts against the second driving member 210. The third connecting rod 240 is disposed in the second receiving groove 121 and connected between the second piezoelectric ceramic element 220 and the striker assembly 230. One end of the striker assembly 230 away from the third connecting rod 240 passes through the fluid transmission channel 132 and is movably sealed at the liquid outlet 134.

[0063] The second driving member 210 is connected to the side wall of the second receiving groove 121 and is electrically connected to an external control circuit. The second piezoelectric ceramic element 220 is movably connected to the side wall of the second receiving groove 121 and abuts against the second driving member 210. The second driving member 210 applies a driving voltage to the second piezoelectric ceramic element 220. The second piezoelectric ceramic element 220 utilizes the piezoelectric effect to generate a slight length change under voltage drive and transmits it to the third connecting rod 240 for movement. The striker assembly 230 abuts between the end of the third connecting rod 240 away from the second driving member 210 and the side wall of the second receiving groove 121. The end of the striker assembly 230 away from the third connecting rod 240 passes through the fluid transmission channel 132 and the nozzle and seals the outlet 134, so that the striker assembly 230 is driven to move by the third connecting rod 240, thereby movably sealing the outlet 134, thus realizing the opening and closing of the outlet 134.

[0064] The active spraying device 200 also includes a counter, which is electrically connected to an external circuit and located at the end of the second piezoelectric ceramic element 220 near the second drive member 210, and on the side facing away from the second drive member 210. When the second drive member 210 drives the second piezoelectric ceramic element 220 to make a small displacement, and drives the impact pin assembly 230 to move through the third connecting rod 240, the movement frequency of the impact pin assembly 230 can be obtained by each time the second drive member 210 drives the second piezoelectric ceramic element 220, that is, the second piezoelectric ceramic element 220 strikes the contact of the counter. By setting the counter to monitor the movement frequency of the impact pin assembly 230 and adjusting the travel speed of the nozzle, the spraying of adhesive to the target position can be achieved, preventing uneven spraying.

[0065] Understandably, after the second driving component 210 is connected to the external circuit, it drives the impact pin assembly 230 to move through the second piezoelectric ceramic element 220 and the third connecting rod 240. Each cycle of the impact pin assembly 230 completes one opening and closing of the liquid outlet 134, and a certain amount of fluid is ejected from the nozzle. By controlling the nozzle to move along the target position, under the high-frequency movement of the impact pin assembly 230, the point-like fluid ejected through the liquid outlet 134 can be connected into a line to complete the spraying operation at the target position.

[0066] In one implementation, please refer to Figures 1 to 3The valve body 100 includes a first housing portion 110, a second housing portion 120, and a third housing portion 130 connected to each other. The first housing portion 110 and the second housing portion 120 are arranged opposite to each other. The outer side walls of the first housing portion 110 and the second housing portion 120 are provided with fixing members 600 for fixing the liquid storage cylinder 20. A first receiving groove 111 is formed on the side of the first housing portion 110 away from the second housing portion 120, and the check valve assembly 300 is at least partially located in the first receiving groove 111. A third receiving groove 130 is formed on the side of the second housing portion 120 away from the first housing portion 110. The second receiving groove 121 is at least partially located within the movable injection device 200; a fluid transmission channel 132 is formed within the third housing 130; the first housing 110 and the second housing 120 are located on the same side of the third housing 130; an outlet 134 is formed on the side of the third housing 130 away from the second housing 120; and an inlet 133 is formed on the side of the first housing 110 away from the second housing 120; a valve needle 310 passes through the third housing 130 and is movably connected to the first housing 110.

[0067] The fixing member 600 is connected to the outer wall of the first housing 110 and the second housing 120. The liquid storage cylinder 20 is installed on the end of the fixing member 600 opposite to the first housing 110 and the second housing 120. The fixing member 600 fixes the liquid storage cylinder 20 to the outer wall of the first housing 110 and the second housing 120, thereby enabling the liquid storage cylinder 20 to move synchronously with the valve body 100 for operation. The fixing member 600 can be fixedly connected to the outer wall of the first housing 110 and the second housing 120 by a screw, which facilitates installation and disassembly. The fixing member 600 connects the first housing 110 and the second housing 120 simultaneously, making the installation of the fixing member 600 more stable. Even if the fixing member 600 becomes loose from one housing, it can still be firmly installed on the other housing. In other embodiments, the fixing member 600 can be integrally formed with the first housing 110 or the second housing 120 to enhance the installation firmness and prevent the screw from loosening and falling off due to vibration during operation.

[0068] The third housing 130 can be connected to the first housing 110 and the second housing 120 via screws for easy installation and disassembly. A nozzle connected to the fluid transmission channel 132 is provided on the side of the third housing 130 opposite to the second housing 120. The end of the nozzle opposite to the fluid transmission channel 132 forms an outlet 134. The movable spraying device 200 passes through the fluid transmission channel 132 and the nozzle sequentially, and is movably sealed at the outlet 134. Under the squeezing action of the extruder, the fluid in the reservoir 20 flows into the fluid transmission channel 132 and then into the nozzle. The extruder and the movable spraying device 200 act simultaneously, causing the fluid in the nozzle to be ejected through the outlet 134 with each movement of the movable spraying device 200. During the fluid ejection process, the movable spraying device 200 moves at high speed and simultaneously controls the nozzle to align with the target position, thus connecting the point-like fluid ejected from the outlet 134 into a line to complete the spraying operation at the target position.

[0069] The third housing 130 has a liquid inlet 133 on the side opposite to the first housing 110. The opening of the liquid storage cylinder 20 is located at the liquid inlet 133 and communicates with the fluid transmission channel 132. One end of the valve needle 310 is located in the first housing 110 and connected to the first transmission assembly, while the other end passes through the third housing 130 and is movably disposed in the fluid transmission channel 132. When the movable injection device 200 is raised to allow liquid inflow, the first drive member 320 is activated, driving the first transmission assembly to move the valve needle 310 to the first position, so that the fluid transmission channel 132 is in a conductive state. The fluid in the liquid storage cylinder 20 flows into the fluid transmission channel 132 and smoothly flows into the nozzle along the fluid transmission channel 132. When the active spray device 200 presses down to discharge liquid, the first drive component 320 drives the valve needle 310 to move to the second position through the first transmission component, so that the fluid transmission channel 132 is in a blocked state; at this time, the valve needle 310 blocks the fluid transmission channel 132 to prevent the fluid in the nozzle from flowing back, and the fluid can only be sprayed out at high speed from the liquid outlet 134 to complete the precise spraying operation.

[0070] In other embodiments, the first shell portion 110 and the second shell portion 120 may also be integrally formed. That is, the first shell portion 110 and the second shell portion 120 are the same shell portion, and the first receiving groove 111 and the second receiving groove 121 are respectively machined on the two opposite sides of the same shell portion.

[0071] In one implementation, please refer to 1 to Figure 3 Both the first shell portion 110 and the second shell portion 120 are provided with heat dissipation components 500, which are located on the outer side wall of the corresponding shell portion.

[0072] Both the first housing 110 and the second housing 120 are provided with heat dissipation components 500. The heat dissipation component 500 on the first housing 110 is connected to the outer wall of the first housing 110, and the heat dissipation component 500 on the second housing 120 is connected to the outer wall of the second housing 120. Taking the heat dissipation component 500 on the second housing 120 as an example, the heat dissipation component 500 includes a heat dissipation body, an input pipe, and an output pipe. The heat dissipation body is connected to the outer wall of the second housing 120 and is close to the movable spraying device 200. A heat dissipation cavity (not shown in the figure) for the flow of cryogenic liquid or cryogenic gas is formed inside the heat dissipation body, and both the input pipe and the output pipe are connected to the heat dissipation body. During the spraying operation, due to the high-speed movement of the movable spraying device 200, a large amount of heat is generated by friction, and the heat is conducted to the heat dissipation body through the second housing 120. Cryogenic liquid or gas is injected into the heat dissipation cavity of the heat sink through the inlet pipe. During its flow within the cavity, the liquid or gas exchanges heat with the heat sink. The liquid or gas, having completed the heat exchange, exits the cavity through the outlet pipe, carrying away heat and thus cooling the second housing 120. This prevents the movable spray device 200 from overheating during spraying, which could affect its performance. Similarly, the high-speed movement of the check valve assembly 300 generates significant heat through friction. This heat is conducted through the first housing 110 to the heat sink 500, cooling the first housing 110 and preventing the check valve assembly 300 from overheating during the movement of the valve needle 310, which could also affect its performance.

[0073] In other embodiments, the first housing portion 110 and the second housing portion 120 may also share a heat sink 500. A third receiving groove is formed on the opposite side of the first housing portion 110 and the second housing portion 120, and the heat sink 500 is disposed in the third receiving groove and connected to the outer side wall of the first housing portion 110 and the second housing portion 120.

[0074] This utility model also proposes a glue spraying device, which includes a piezoelectric jet valve. The specific structure of the piezoelectric jet valve is as described in the above embodiments. Since the glue spraying device adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0075] The above description is merely an exemplary embodiment of the present utility model and does not limit the scope of protection of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present utility model.

Claims

1. A piezoelectric injection valve for mounting a liquid storage tank and injecting fluid from the liquid storage tank, characterized in that, The piezoelectric injection valve includes: The valve body has a receiving cavity and an inlet and an outlet communicating with the receiving cavity. A fluid transmission channel and an outlet communicating with the fluid transmission channel are formed in the receiving cavity. The two ends of the fluid transmission channel are respectively connected to the inlet and the outlet. A movable spraying device is located on the valve body and movably seals the liquid outlet; and The check valve assembly includes a first drive member, a first piezoelectric ceramic element, a first displacement amplification mechanism, and a valve needle disposed on the valve body. The first drive member is drivenly connected to the first piezoelectric ceramic element, and the first displacement amplification mechanism is connected between the first piezoelectric ceramic element and the valve needle. The valve needle is inserted into the receiving cavity corresponding to the through-hole and can move axially thereto, so that the valve needle has a first position that opens the fluid transmission channel and a second position that blocks the fluid transmission channel.

2. The piezoelectric injection valve as described in claim 1, characterized in that, The valve body has a first receiving groove. The first groove sidewall of the first receiving groove is connected to the first driving member and the first rotating shaft. The first piezoelectric ceramic element includes a first ceramic strip and a second ceramic strip that are intersected and connected. The first ceramic strip is movably connected to the groove sidewall of the first receiving groove and abuts against the first driving member and the first rotating shaft. The second ceramic strip is disposed in the first receiving groove. One end of the second ceramic strip abuts against the side of the first ceramic strip opposite to the first rotating shaft, and the other end movably abuts against the first displacement amplification mechanism.

3. The piezoelectric injection valve as described in claim 2, characterized in that, The second sidewall of the first receiving groove is provided with a second rotating shaft. The second sidewall of the groove is arranged opposite to the first sidewall of the groove. The first displacement amplification mechanism includes a first connecting rod. One end of the first connecting rod abuts against the second rotating shaft on the side away from the second ceramic strip, and the other end is connected to the valve needle.

4. The piezoelectric injection valve as described in claim 3, characterized in that, The third groove sidewall of the first receiving groove is provided with a third rotating shaft, and the third groove sidewall and the second groove sidewall form a stepped structure. The first displacement amplification mechanism also includes a second connecting rod. One end of the second connecting rod abuts against the third rotating shaft and moves against the first connecting rod on the side away from the third rotating shaft. The other end of the second connecting rod abuts against the valve needle.

5. The piezoelectric injection valve as described in claim 1, characterized in that, The fluid transmission channel includes two spaced-apart transmission sections, with the gap between the two transmission sections forming the through port. The valve needle forms a liquid passage. At the first position, the liquid passage is connected to both transmission sections. At the second position, the ports of the two transmission sections at their closest ends are positioned opposite to the outer peripheral wall of the valve needle.

6. The piezoelectric injection valve as described in claim 5, characterized in that, There is a gap between the ports of the two transmission segments at their closest points to each other and the valve needle; And / or, the two transmission segments are configured to connect a first transmission segment to the inlet and a second transmission segment to the outlet, wherein the length of the second transmission segment is less than or equal to the length of the first transmission segment.

7. The piezoelectric injection valve as described in claim 1, characterized in that, The piezoelectric injection valve further includes a sealing element disposed within the receiving cavity. The sealing element is connected to the inner wall surface of the receiving cavity and sleeved on the outer side of the valve needle. The inner peripheral wall of the sealing element has a lip that abuts against the valve needle.

8. The piezoelectric injection valve as described in claim 1, characterized in that, The valve body has a second receiving groove. The movable injection device includes a second driving member, a second piezoelectric ceramic element, a third connecting rod, and a striker assembly. The second driving member is connected to the side wall of the second receiving groove. The second piezoelectric ceramic element is movably connected to the side wall of the second receiving groove and abuts against the second driving member. The third connecting rod is disposed in the second receiving groove and connected between the second piezoelectric ceramic element and the striker assembly. One end of the striker assembly away from the third connecting rod passes through the fluid transmission channel and movably seals the liquid outlet.

9. The piezoelectric injection valve as described in claim 1, characterized in that, The valve body includes a first shell, a second shell, and a third shell connected to each other. The first shell and the second shell are arranged opposite to each other. The outer side walls of the first shell and the second shell are provided with fixing members for fixing the liquid storage cylinder. A first receiving groove is formed on the side of the first shell away from the second shell, and the check valve assembly is at least partially located in the first receiving groove. A second receiving groove is formed on the side of the second shell away from the first shell, and the movable injection device is at least partially located in the second receiving groove. The fluid transmission channel is formed inside the third shell. The first shell and the second shell are located on the same side of the third shell. The liquid outlet is formed on the side of the third shell away from the second shell, and the liquid inlet is formed on the side of the first shell away from the second shell. The valve needle passes through the third shell and is movably connected to the first shell.

10. A glue spraying device, characterized in that, Includes the piezoelectric injection valve as described in any one of claims 1 to 9.

Images