Piezoelectric valve and piezoelectric injection device using the same

Abstract

This invention provides a piezoelectric valve and a piezoelectric injection device applicable thereto. The piezoelectric valve includes a valve body, a piezoelectric drive rod, an adjusting assembly, a power output assembly, and a striking pin. The piezoelectric drive rod is disposed within the internal space of the valve body. The adjusting assembly is connected to the upper end of the piezoelectric drive rod. The power output assembly is connected to the lower end of the piezoelectric drive rod and includes a power output shaft and a power output lever. The bottom and top of the power output lever, near the first end, respectively abut against the power output shaft and the lower end of the piezoelectric drive rod. The top of the striking pin abuts against the bottom of the lever near the second end. A double-sided support structure, consisting of an arc portion and at least two supporting surfaces, is provided between the adjusting assembly and the upper end of the piezoelectric drive rod, between the lower end of the piezoelectric drive rod and the power output lever, between the adjusting assembly and the inner wall of the valve body, and / or between the power output assembly and the inner wall of the valve body, providing stable support and limiting functions.

Description

Technical Field

[0001] This invention relates to an improvement in the structure of a piezoelectric valve, particularly a piezoelectric valve with a double-sided support structure. Prior Technology

[0002] Piezoelectric valves primarily use a piezoelectric actuator to generate thrust, pushing high-viscosity colloids into the valve body to achieve a spraying effect. However, since the movement of the piezoelectric actuator is relatively small, the amount of colloid that can be pushed is limited. Therefore, a lever mechanism is usually used to amplify the movement of the piezoelectric actuator, making it sufficient to push the colloid.

[0003] Specifically, a lever mechanism consists of a pivot and a lever. The force-applying arm is the distance between the point of application of force and the fulcrum, while the amplifying arm is the distance between the point of output force and the fulcrum. The amplification factor of the movement is determined by the ratio of the amplifying arm length to the force-applying arm length. For example, when the force-applying arm length is 2mm and the amplifying arm length is 14mm, the amplification factor is 14 / 2 = 7 times. That is, when the applied force movement is 0.03mm, the movement amplified by the lever mechanism can reach 0.21mm. However, in traditional lever mechanisms, the contact between the pivot and the lever is usually a single-point contact, which can cause the pivot to slip during operation, thus changing the position of the fulcrum. For example, when the fulcrum position slips by 0.1mm, the force-applying arm length will change from 2mm to 1.9mm, and the amplifying arm length will change from 14mm to 14.1mm. In this case, the new amplification factor will become 14.1 / 1.9 = 7.42 times. In other words, when the applied force movement is 0.03mm, the amplified movement will become 0.2226mm, which will produce an error of about 6%, ultimately resulting in inaccurate glue dispensing. Summary of the Invention

[0004] The purpose of this invention is to provide a piezoelectric valve that can solve the above-mentioned problems.

[0005] To achieve the above objectives, the present invention provides a piezoelectric valve. The piezoelectric valve is suitable for connection to a glue cartridge and includes a valve body, a piezoelectric actuator, an adjusting assembly, a power output assembly, and a striking pin. The valve body has an internal space. The piezoelectric actuator is disposed within the internal space. The adjusting assembly is connected to the upper end of the piezoelectric actuator and configured to adjust the position of the piezoelectric actuator. The power output assembly is connected to the lower end of the piezoelectric actuator and includes a power output shaft and a power output lever, wherein the power output lever has opposing first and second ends. The power output shaft is disposed in the lower part of the internal space and abuts against the bottom of the power output lever near the first end, and the top of the power output lever abuts against the lower end of the piezoelectric actuator near the first end. The striking pin is disposed at the bottom of the valve body, wherein the top of the striking pin abuts against the bottom of the power output lever near the second end and is configured to actuate the glue supplied by the glue cartridge. A double-sided support structure is provided at one or more of the following locations: between the adjustment component and the upper end of the piezoelectric drive rod, between the lower end of the piezoelectric drive rod and the output lever, between the adjustment component and the inner wall of the internal space, and between the output component and the inner wall of the internal space. The double-sided support structure is composed of an arc portion and at least two support surfaces that abut against the surface of the arc portion.

[0006] In one embodiment of the present invention, at least two of the above-mentioned support surfaces are disposed at the bottom of the output lever near the first end, and the surface of the arc portion is the surface of the output shaft.

[0007] In one embodiment of the present invention, at least two of the above-mentioned support surfaces are disposed at the lower end of the piezoelectric drive rod, and the arc portion is a protruding structure disposed at the top of the output lever near the first end.

[0008] In one embodiment of the present invention, the adjustment assembly includes a first adjustment shaft and an adjustment lever, wherein the adjustment lever has a first end and a second end opposite to each other. The first adjustment shaft is disposed in the upper part of the internal space and abuts against the top of the adjustment lever near the first end. The bottom of the adjustment lever near the first end abuts against the upper end of the piezoelectric drive rod. At least two support surfaces are disposed at the top of the adjustment lever near the first end, and the surface of the arcuate portion is the surface of the first adjustment shaft.

[0009] In one embodiment of the present invention, the adjustment assembly further includes a second adjustment shaft disposed between the adjustment lever and the upper end of the piezoelectric drive rod. At least two support surfaces are disposed on the upper end of the piezoelectric drive rod, and the surface of the arcuate portion is the surface of the second adjustment shaft.

[0010] In one embodiment of the present invention, the above-mentioned at least two supporting surfaces include two planes, two arc surfaces, or a combination of at least one plane and at least one arc surface.

[0011] In one embodiment of the present invention, at least two of the above-mentioned support surfaces are either directly connected to each other or not directly connected.

[0012] In one embodiment of the present invention, the at least two supporting surfaces and the surface of the arc portion are in contact at at least two contact points, wherein the included angle between the two tangents passing through the at least two contact points is in the range of 60 to 150 degrees.

[0013] In one embodiment of the present invention, the aforementioned output shaft is a protruding shaft structure protruding from the inner wall of the internal space.

[0014] To achieve the above objectives, the present invention further provides a piezoelectric jetting device. This piezoelectric jetting device includes a glue cartridge, the aforementioned piezoelectric valve, and a glue supply tube. The bottom of the valve body of the piezoelectric valve is provided with a nozzle seat, and the bottom of the striking pin extends to the nozzle seat. The glue supply tube connects the glue cartridge and the nozzle seat, wherein the striking pin is configured to push the glue supplied by the glue supply tube to be ejected from the nozzle seat.

[0015] As described above, the double-sided support structure provided by this invention can be installed between components that require relative rotation or oscillation within the internal structure of a piezoelectric valve, providing dual-point support for the rotating or oscillating components. This enables the positioning of the fulcrum and ensures stable lever output ratio. Furthermore, the double-sided support structure not only improves the operational stability of components within the internal structure of the piezoelectric valve but also enhances the accuracy of their installation and positioning. Simple Explanation of the Diagram

[0016] Figure 1 is a schematic diagram of the structure of a piezoelectric jetting device according to one embodiment of the present invention. Figure 2 is an enlarged schematic diagram of part A of Figure 1. Figure 3 is a schematic diagram of a double-sided support structure according to one embodiment of the present invention. Figures 4 to 6 are schematic diagrams of a double-sided support structure according to different embodiments of the present invention. Figure 7 is an enlarged schematic diagram of part B of Figure 1. Implementation

[0017] To make the above and other objects, features, and advantages of the present invention more apparent and understandable, preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Furthermore, the directional terms used in this invention, such as up, down, top, bottom, front, back, left, right, inside, outside, side, surrounding, center, horizontal, transverse, vertical, longitudinal, axial, radial, uppermost, or lowermost, are merely for reference to the accompanying drawings. Therefore, the directional terms used are for illustrating and understanding the present invention, and not for limiting the present invention.

[0018] Please refer to Figures 1 to 3. The piezoelectric jetting device 1 in this embodiment mainly includes a piezoelectric valve 2, a glue cartridge 3, and a glue supply pipe 4. The glue supply pipe 4 is connected between the piezoelectric valve 2 and the glue cartridge 3, and is configured to deliver the glue in the glue cartridge 3 to the piezoelectric valve 2, and then jet it through the piezoelectric valve 2.

[0019] Specifically, the piezoelectric valve 2 includes a valve body 21, a piezoelectric actuator 22, an adjustment assembly 23, an output assembly 24, and a striking pin 25. The valve body 21 has an internal space 21a and a nozzle seat 26 at its bottom. The striking pin 25 is located at the bottom of the internal space 21a (i.e., the striking pin 25 is located at the bottom of the valve body 21) and extends to the nozzle seat 26. The piezoelectric actuator 22 is installed in the internal space 21a and extends or retracts according to the piezoelectric effect when energized. The adjustment assembly 23 is connected to the upper end 221 of the piezoelectric actuator 22 and is used to adjust the position or range of motion of the piezoelectric actuator 22. The output assembly 24 is connected to the lower end 222 of the piezoelectric actuator 22 and, under the extension and retraction of the piezoelectric actuator, further pushes the striking pin 25. When the striking pin 25 is pushed, the adhesive is sprayed from the adhesive supply tube 4 through the nozzle seat 26.

[0020] As shown in Figure 2, the output assembly 24 includes an output shaft 241 and an output lever 242. The output shaft 241 is disposed in the lower part of the internal space 21a, serving as a fulcrum. In one embodiment, the output shaft 241 may be disposed in the inner wall (e.g., the bottom wall) of the internal space 21a and may be accommodated in a groove on the bottom wall, or the output shaft 241 may be a protruding shaft extending from the bottom wall. The output lever 242 has two opposing ends, namely a first end 242a and a second end 242b, and the bottom of the output lever 242 near the first end 242a abuts against the output shaft 241 and swings around the output shaft 241. The top of the output lever 242 near the first end 242a abuts against the lower end 222 of the piezoelectric drive rod 22. The bottom of the output lever 242 near the second end 242b abuts against the top of the striker 25. When the piezoelectric drive rod 22 extends or retracts, it can drive the output lever 242 to swing around the output shaft 241, thereby pressing the striker 25.

[0021] In one embodiment, a double-sided support structure 5 is provided between the output component 24 and the inner wall of the internal space 21a. This double-sided support structure 5 consists of an arcuate portion 51 and at least two support surfaces (e.g., support surface 52 and support surface 53), with support surface 52 and support surface 53 respectively contacting the surface of the arcuate portion 51. In this embodiment, support surface 52 and support surface 53 are located at the bottom of the output lever 242, near the first end 242a, and the surface of the arcuate portion 51 is the surface of the output shaft 241. Thus, through the design of support surface 52 and support surface 53, when the output lever 242 swings relative to the output shaft 241, it can swing stably with the axis of the output shaft 241 as the fulcrum. Furthermore, through the design of at least two support surfaces 52 and support surface 53, the stress of the structure can be effectively dispersed, thereby reducing the risk of structural damage and improving durability.

[0022] In this embodiment, as shown in FIG3, the support surface 52 and the support surface 53 are two planes directly connected to each other, and the included angle A1 between the support surface 52 and the support surface 53 ranges from 60 to 150 degrees. Furthermore, the support surface 52 and the support surface 53 contact the surface of the arc portion 51 at at least two contact points, and the included angle of the tangents between these contact points ranges from 60 to 150 degrees. When the included angle A1 is less than 150 degrees, a better limiting effect is provided because the force component ratio gradually increases; while when the included angle A1 is greater than 60 degrees, stress concentration can be avoided, thereby maintaining the smooth swing of the output lever 242.

[0023] It should be noted that the support surfaces 52 and 53 of the double-sided support structure 5 are not limited to a continuous planar design. In other embodiments, such as shown in Figure 4, the support surfaces 52 and 53 can also be discontinuous planar designs, that is, the support surfaces 52 and 53 in Figure 4 are not directly connected. In other embodiments, such as shown in Figure 5, the support surfaces 52 and 53 can also be convex arc surfaces, or as shown in Figure 6, the support surfaces 52 and 53 can be a combination of planar and arc surfaces. As long as the support surfaces 52 and 53 of the double-sided support structure 5 can form contact at at least two points on the surface of the arc portion 51, and achieve the purpose of restricting the movement of the arc portion 51, an effective support and limiting function can be achieved. Similarly, in the embodiments of Figures 4 to 6, the included angle between the two tangents formed by the at least two contact points of the support surfaces 52 and 53 with the surface of the arc portion 51 ranges from 60 to 150 degrees.

[0024] Referring again to Figures 1 and 2, in one embodiment, a double-sided support structure 6 may also be provided between the lower end 222 of the piezoelectric drive rod 22 and the output lever 242. The design principle of the double-sided support structure 6 is the same as that of the double-sided support structure 5. Specifically, the double-sided support structure 6 is composed of an arc portion 61 and at least two support surfaces (e.g., support surface 62 and support surface 63), with support surface 62 and support surface 63 respectively contacting the surface of the arc portion 61. In this embodiment, support surface 62 and support surface 63 are provided at the lower end 222 of the piezoelectric drive rod 22, and the arc portion 61 is a protruding structure provided at the top of the output lever 242 near the first end 242a. Thus, through the design of the support surface 62 and support surface 63 at the lower end 222 of the piezoelectric drive rod 22, it can be ensured that the output lever 242 maintains a stable oscillation with the axis of the output shaft 241 as the fulcrum when oscillating relative to the output shaft 241. In some embodiments, the design principles of support surfaces 62 and 63 are the same as those of support surfaces 52 and 53. For example, support surfaces 62 and 63 can be planes, curved surfaces, or a combination of planes and curved surfaces, or they can be directly connected continuous planes or non-directly connected discontinuous planes, all of which can achieve the same support and limiting effect.

[0025] Referring also to Figures 1 and 7, in one embodiment, the adjustment assembly 23 includes a first adjustment shaft 231, a second adjustment shaft 232, an adjustment lever 233, and an adjustment knob 234. The first adjustment shaft 231 is disposed in the upper part of the internal space 21a, serving as a fulcrum. In one embodiment, the first adjustment shaft 231 is disposed in the top wall of the internal space 21a and can be accommodated in a groove on the top wall, or the first adjustment shaft 231 can be a protruding shaft extending from the top wall. The adjustment lever 233 has two ends, a first end 233a and a second end 233b, and the top of the adjustment lever 233 near the first end 233a abuts against the first adjustment shaft 231 and can swing around the first adjustment shaft 231. The bottom of the adjustment lever 233 near the first end 233a abuts against the upper end 221 of the piezoelectric drive rod 22. The adjustment knob 234 abuts against the top of the adjustment lever 233 near the second end 233b. In this way, the rotation angle of the adjusting lever 233 can be controlled by adjusting the knob 234, thereby linking the position of the upper end 221 of the piezoelectric drive rod 22 with the engagement end of the adjusting lever 233, and thus adjusting the position of the piezoelectric drive rod 22.

[0026] In one embodiment, a double-sided support structure 7 is provided between the adjusting component 23 and the inner wall (e.g., the top wall) of the internal space 21a. The design principle of this double-sided support structure 7 is the same as that of the double-sided support structure 5, also consisting of an arcuate portion 71 and at least two support surfaces (e.g., support surface 72 and support surface 73), with support surface 72 and support surface 73 respectively contacting the surface of the arcuate portion 71. In this embodiment, support surface 72 and support surface 73 are located at the top of the adjusting lever 233 near the first end 233a, and the surface of the arcuate portion 71 is the surface of the first adjusting shaft 231. Thus, through the design of support surface 72 and support surface 73, when the adjusting lever 233 swings relative to the first adjusting shaft 231, it can swing stably with the axis of the first adjusting shaft 231 as the fulcrum.

[0027] As shown in Figures 1 and 7, in some embodiments, a double-sided support structure 8 may also be provided between the upper end 221 of the piezoelectric drive rod 22 and the adjusting lever 233. The design principle of the double-sided support structure 8 is the same as that of the double-sided support structure 5. Specifically, the double-sided support structure 8 is composed of an arc portion 81 and at least two support surfaces (e.g., support surface 82 and support surface 83), with support surface 82 and support surface 83 respectively contacting the surface of the arc portion 81. In this embodiment, support surface 82 and support surface 83 are disposed at the upper end 221 of the piezoelectric drive rod 22, and the surface of the arc portion 81 is the surface of the second adjusting shaft 232. Thus, through the design of support surface 82 and support surface 83 at the upper end 221 of the piezoelectric drive rod 22, it can be ensured that the adjusting lever 233 can rotate stably. In some embodiments, the design principles of support surface 72 and support surface 73, as well as support surface 82 and support surface 83, are the same as those of support surface 52 and support surface 53, and will not be described again here.

[0028] It should be noted that although this invention demonstrates the arrangement of four sets of double-sided support structures (i.e., double-sided support structure 5, double-sided support structure 6, double-sided support structure 7, and double-sided support structure 8) in the valve body 21, this is not intended to limit the number of double-sided support structures in this invention. The number of these double-sided support structures can be adjusted as needed and can be selectively arranged in one or more of the following locations: between the adjusting component 23 and the upper end 221 of the piezoelectric drive rod 22, between the lower end 222 of the piezoelectric drive rod 22 and the output lever 242, between the adjusting component 23 and the inner wall of the valve body 21, and between the output component and the inner wall of the valve body 21, thereby achieving positioning and support for components within the internal structure of the piezoelectric valve that require relative rotation or oscillation. This enables the positioning and support of components within the internal structure of the piezoelectric valve that require relative rotation or oscillation.

[0029] As can be seen from the embodiments of the present invention described above, the double-sided support structure provided by the present invention can be installed between components that need to rotate or oscillate relative to each other in the internal structure of the piezoelectric valve, providing a double-point support function for the rotating or oscillating components, thereby enabling the positioning of the fulcrum and ensuring the stability of the lever output ratio. In addition, through the design of the double-sided support structure, not only can the actuation stability of the components in the internal structure of the piezoelectric valve be improved, but the installation and positioning accuracy of these components can also be improved.

[0030] Although the present invention has been disclosed with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art may make various modifications and alterations without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

[0031] 1: Piezoelectric jetting device 2: Piezoelectric valve 21: Valve body 21a: Interior space 22: Piezoelectric drive rod 221: Upper end 222: Lower end 23: Adjust components 231: First Adjustment Shaft 232: Second Adjustment Shaft 233: Adjust the lever 233a: First end 233b: Second end 234: Adjusting the knob 24: Output Components 241: Output shaft 242: Output lever 242a: First end 242b: Second end 25: Firing pin 26: Nozzle seat 3: Glue tube 4: Glue supply hose 5: Double-sided support structure 51: Arc section 52: Support surface 53: Support surface 6: Double-sided support structure 61: Arc section 62: Support surface 63: Support surface 7: Double-sided support structure 71: Arc section 72: Support surface 73: Support surface 8: Double-sided support structure 81: Arc section 82: Support surface 83: Support surface A: Enlarged portion of Figure 1 B: Enlarged portion of Figure 1 A1: Angle

Claims

1. A piezoelectric valve suitable for connecting to a glue cartridge and comprising: a valve body having an internal space; a piezoelectric actuator disposed in the internal space; an adjustment assembly connected to an upper end of the piezoelectric actuator and configured to adjust the position of the piezoelectric actuator; an output assembly connected to a lower end of the piezoelectric actuator, the output assembly comprising an output shaft and an output lever, wherein the output lever has opposing first and second ends, the output shaft is disposed in the lower part of the internal space and abuts against the bottom of the output lever near the first end, and the top of the output lever near the first end abuts against the lower end of the piezoelectric actuator; and a striker disposed at the bottom of the valve body, wherein the top of the striker abuts against the bottom of the output lever near the second end and is configured to actuate glue supplied by the glue cartridge. A double-sided support structure is provided at one or more of the following locations: between the adjustment component and the upper end of the piezoelectric drive rod, between the lower end of the piezoelectric drive rod and the output lever, between the adjustment component and the inner wall of the internal space, and between the output component and the inner wall of the internal space. The double-sided support structure is composed of an arc portion and at least two support surfaces that abut against the surface of the arc portion. The at least two support surfaces and the surface of the arc portion are in contact at at least two contact points, and the included angle between the two tangents passing through the at least two contact points is in the range of 60 to 150 degrees.

2. The piezoelectric valve as claimed in claim 1, wherein the at least two support surfaces are disposed at the bottom of the output lever near the first end, and the surface of the arcuate portion is the surface of the output shaft.

3. The piezoelectric valve as claimed in claim 1, wherein the at least two support surfaces are disposed at the lower end of the piezoelectric drive rod, and the arcuate portion is a protruding structure disposed at the top of the output lever near the first end.

4. The piezoelectric valve as described in claim 1, wherein: The adjustment assembly includes a first adjustment shaft and an adjustment lever, wherein the adjustment lever has a first end and a second end opposite to each other, the first adjustment shaft is disposed in the upper part of the internal space and abuts against the top of the adjustment lever near the first end, the bottom of the adjustment lever near the first end abuts against the upper end of the piezoelectric drive rod; and the at least two support surfaces are disposed at the top of the adjustment lever near the first end, the surface of the arc portion is the surface of the first adjustment shaft.

5. The piezoelectric valve as described in claim 4, wherein: The adjustment assembly also includes a second adjustment shaft disposed between the adjustment lever and the upper end of the piezoelectric drive rod; and the at least two support surfaces are disposed at the upper end of the piezoelectric drive rod, with the surface of the arcuate portion being the surface of the second adjustment shaft.

6. The piezoelectric valve as described in any one of claims 1 to 5, wherein the at least two support surfaces comprise two planes, two arcuate surfaces, or a combination of at least one plane and at least one arcuate surface.

7. The piezoelectric valve as described in claim 6, wherein the at least two support surfaces are directly connected to each other or not directly connected.

8. The piezoelectric valve as described in any one of claims 1 to 5, wherein the output shaft is a convex shaft structure protruding from the inner wall of the internal space.

9. A piezoelectric jetting device comprising: a glue cartridge configured to supply glue; a piezoelectric valve as claimed in claim 1, wherein a nozzle seat is provided at the bottom of the valve body and the bottom of the ejector pin extends to the nozzle seat; and a glue supply tube connecting the glue cartridge and the nozzle seat, wherein the ejector pin is configured to actuate the glue supplied by the glue supply tube from the nozzle seat.

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