Drip-proof needle valve mechanism and glue gun

Abstract

The utility model discloses a kind of drip-proof needle valve mechanisms, including adapter block, and needle is arranged in adapter block, adapter block includes air cavity, and glue cavity is arranged below air cavity, the top of needle is equipped with leather bowl, leather bowl is arranged in air cavity, air cavity has first air inlet and second air inlet, first, second air inlet is located above and below leather bowl respectively, the nozzle of adapter block below is equipped with, nozzle has glue outlet, needle is inserted nozzle and is set correspondingly with glue outlet below, when first air inlet air, needle presses down and closes glue outlet, when second air inlet air, needle goes up and separates glue outlet. The utility model needle realizes the quick glue of glue gun and broken glue, needle higher degree of adhesion, not easy to wear, can achieve basically no drip.

Description

Technical Field

[0001] This utility model relates to the field of glue gun technology, and in particular to an anti-drip needle valve mechanism and a glue gun. Background Technology

[0002] A glue gun is a tool used for dispensing or spraying glue. In high-precision glue application, the needle valve mechanism is the core component controlling the glue output switch. Its sealing performance and the response speed of the glue dispensing switch directly affect the glue application quality. Existing needle valve mechanisms generally have two major pain points: First, the "leaking problem"—after the glue dispensing stops, the ejector pin and the glue outlet are not sealed tightly, and residual glue drips off under the pressure of the glue path and gravity, contaminating the workpiece surface or causing deviations in the glue application amount; second, "insufficient control precision"—the stroke of the ejector pin's up and down movement is difficult to adjust precisely, and poor air chamber sealing can easily lead to pressure transmission failure, resulting in problems such as glue dispensing interruption and unstable glue dispensing volume. Utility Model Content

[0003] The purpose of this invention is to solve the technical problems of glue guns being prone to dripping and having poor glue dispensing control accuracy.

[0004] To achieve the objectives of this utility model, the following technical solution is adopted: A drip-proof needle valve mechanism includes an adapter block and a pin disposed within the adapter block. The adapter block includes an air chamber and a glue chamber disposed below the air chamber. A cup is provided above the pin and is disposed in the air chamber. The air chamber has a first air inlet and a second air inlet, which are located above and below the cup, respectively. A nozzle is provided below the adapter block, and the nozzle has a glue outlet. The nozzle is inserted below the pin and is positioned corresponding to the glue outlet. When air enters through the first air inlet, the pin presses down to close the glue outlet. When air enters through the second air inlet, the pin moves upward and disengages from the glue outlet.

[0005] In some embodiments, the adapter block is provided with a valve seat, and an adjusting member is provided inside the valve seat. The adjusting member is movably connected to the valve seat and abuts against the ejector pin.

[0006] In some embodiments, the valve seat is provided with a threaded component, and the adjusting component is threadedly connected to the threaded component.

[0007] In some embodiments, one end of the ejector pin is provided with a tapered portion, which is disposed opposite to the glue outlet hole, and the glue outlet hole is a tapered hole and corresponds to the tapered portion.

[0008] In some embodiments, the tapered portion includes a tip portion and a frustum portion disposed between the tip portion and the ejector pin. The tapered hole includes a first tapered hole, a second tapered hole, and a straight hole communicating with the second tapered hole. When the ejector pin is pressed down to close the dispensing hole, the tip portion is inserted into the straight hole through the tapered hole and fits against the second tapered hole.

[0009] In some embodiments, one end of the adapter block is provided with a sleeve, and the sleeve is connected to the nozzle by fasteners.

[0010] In some embodiments, the leather cup includes a first sealing part and a second sealing part arranged symmetrically, and the first and second sealing parts abut against the inner wall of the air cavity.

[0011] In some embodiments, the first air inlet and the second air inlet are connected to a solenoid valve, which switches the air intake of the first and second air inlets.

[0012] In some embodiments, the glue cavity has a glue inlet channel, which is inclined downwards.

[0013] A glue gun includes a gun base and an anti-drip needle valve mechanism, the anti-drip needle valve mechanism being disposed on the side of the gun base, and the glue cavity being connected to the glue supply channel of the gun base.

[0014] The anti-drip needle valve mechanism and glue gun provided by this utility model have the following advantages: This utility model's ejector pin uses two air inlets. By switching between different air inlets using a solenoid valve, the ejector pin is pushed up and pressed down. The sharp end of the ejector pin and the conical hole inside the nozzle come into contact and separate, thus achieving the dispensing and cutting off of glue by the glue gun. Due to the short stroke and rapid glue cutting, compared with traditional round-head ejector pins, the fit is higher, it is not easy to wear, and it can achieve virtually no dripping. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments 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 these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of an anti-drip needle valve mechanism provided in Embodiment 1 of this utility model.

[0017] Figure 2 This is a utility model Figure 1 A schematic diagram of section AA.

[0018] Figure 3 This is a schematic diagram of the adapter block provided in Embodiment 1 of this utility model.

[0019] Figure 4 This is a cross-sectional view of the adapter block provided in Embodiment 1 of this utility model.

[0020] Figure 5 This is a schematic diagram of the ejector pin and nozzle provided in Embodiment 1 of this utility model.

[0021] Figure 6 This is a utility model Figure 5 Enlarged view of section A.

[0022] Figure 7 This is a schematic diagram of the glue gun provided in Embodiment 2 of this utility model.

[0023] In the attached diagram: 1. Adapter block; 2. Ejector pin; 3. Nozzle; 4. Solenoid valve; 5. Sleeve; 6. Fastener; 7. Gun base; 11. Air chamber; 12. Glue chamber; 14. Valve seat; 15. Adjusting component; 16. Threaded component; 21. Leather cup; 22. Conical part; 31. Glue outlet hole; 71. Glue supply channel; 111. First air inlet; 112. Second air inlet; 121. Glue inlet channel; 131. Retaining ring; 132. Gasket; 211. First sealing part; 212. Second sealing part; 221. Tip part; 222. Frustum part; 311. First conical hole; 312. Second conical hole; 313. Straight hole. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0025] In this embodiment, "several" and "more than" refer to two or more. In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] <Example 1> like Figures 1 to 6As shown, this embodiment provides an anti-drip needle valve mechanism, including an adapter block 1 and a ejector pin 2 disposed within the adapter block 1. The ejector pin 2 controls the dispensing of adhesive by moving up and down. The ejector pin passes through the central hole of the adapter block and can slide up and down axially. The adapter block 1 contains two independent air chambers 11 and adhesive chambers 12. The air chamber 11 is located at the top and provides the power for the up and down movement of the ejector pin 2. The adhesive chamber is located below the air chamber 11 and temporarily stores the adhesive to be dispensed. The two are isolated by a sealing structure to prevent adhesive from seeping into the air chamber. The sealing structure includes a retaining ring 131 and a gasket 132. A cup 21 is located above the ejector pin 2 and is disposed within the air chamber 11, forming a sealed fit with the inner wall of the air chamber 11. The air chamber 11 has a first air inlet 111 and a second air inlet 112, located above and below the cup 21 respectively, forming a "bidirectional air intake" structure. To achieve automated air intake switching, both the first air inlet 11 and the second air inlet 112 are connected to a solenoid valve 4. The solenoid valve 4 controls the airflow through an electrical signal, enabling air intake switching to be completed in a short time, ensuring rapid response of the ejector pin and avoiding glue quantity deviation due to switching delay. A nozzle 3 is provided below the adapter block 1, and the nozzle 3 has a glue outlet 31. The ejector pin 2 is inserted below the nozzle 3 and is correspondingly positioned to the glue outlet 31. When air enters through the first air inlet 111, the ejector pin 2 presses down to close the glue outlet 31; when air enters through the second air inlet 112, the ejector pin moves upward and disengages from the glue outlet 31.

[0028] In the above technical solution, when air enters through the first air inlet 111, the air pressure in the upper chamber of the air chamber 11 increases, pushing the cup 21 downwards, which in turn causes the ejector pin to press down as a whole. The lower end of the ejector pin 2 blocks the glue outlet 31 of the nozzle, thus "stopping glue dispensing". When air enters through the second air inlet 112, the air pressure in the lower chamber of the air chamber 11 increases, pushing the cup 21 upwards, which causes the ejector pin to move upwards as a whole. The lower end of the ejector pin disengages from the glue outlet, and the glue flows out from the glue outlet, thus "starting glue dispensing". In this embodiment, the ejector pin uses two air inlets. By switching between different air inlets using a solenoid valve, the ejector pin is pushed up and pressed down to achieve glue dispensing and glue cut-off. Due to the short stroke, glue cut-off is rapid.

[0029] Furthermore, the upper part of the adapter block 1 is provided with a valve seat 14, which is a hollow cylindrical structure with an adjusting component 15 (such as an adjusting bolt) inside. The adjusting component 15 and the valve seat 14 can move axially, and the lower end of the adjusting component 15 abuts against the upper end of the ejector pin 2. By adjusting the position of the adjusting component 15 inside the valve seat 14, the maximum upward height and downward stroke of the ejector pin can be precisely controlled. For example, when the ejector pin 2 is not sealed tightly, adjusting the adjusting component 15 downward can increase the downward pressure of the ejector pin and ensure that it fits tightly with the dispensing hole. The valve seat 14 is provided with a threaded component 16 (such as a nut), and the outer wall of the adjusting component 15 is provided with an external thread that mates with the internal thread of the threaded component. When the threaded component is rotated, the adjusting component moves axially, and the threaded engagement has a "self-locking" property, which can fix the adjusting component in the set position and prevent the adjustment amount from shifting due to vibration during operation.

[0030] Furthermore, one end of the ejector pin 2 is provided with a tapered portion 22, which is positioned opposite to the glue outlet 31. The glue outlet 31 is a tapered hole and corresponds to the tapered portion 22. The lower end of the ejector pin 2 is also provided with a tapered portion 22, the taper of which is consistent with the taper of the glue outlet 31 of the nozzle 3. When the ejector pin 2 is pressed down, the tapered portion 22 and the tapered hole fit tightly together, forming a "surface seal". Compared with the traditional "line seal", the sealing area is increased, which can completely block the dripping path of residual glue. Specifically, the tapered portion 22 includes a tip 221 and a frustum 222. The tip 221 is located at the lowermost end, and the frustum 222 connects the tip 221 and the body of the ejector pin 2. Correspondingly, the tapered hole includes a first tapered hole 311, a second tapered hole 312, and a straight hole 313. The taper of the second tapered hole 312 is consistent with that of the tip, and the straight hole is located at the lowermost end of the tapered hole, with a diameter that matches the minimum diameter of the tip 221. When the ejector pin is pressed down to seal the dispensing hole, the tip 221 is inserted into the straight hole 313 through the second conical hole 312, and the outer wall of the tip fits into the second conical hole, which can effectively compensate for the slight coaxiality deviation of the ejector pin and ensure the reliability of the seal.

[0031] Furthermore, a sleeve 5 is provided below the adapter block 1. The inner wall of the sleeve 5 is adapted to the outer wall of the nozzle 3, and the two are connected by fasteners 6 (nuts and clips). The fasteners 6 and the sleeve 5 are coaxial to avoid poor sealing between the ejector pin and the dispensing hole due to nozzle misalignment. At the same time, the detachable connection method makes it easy to replace nozzles with different orifice diameters (to adapt to different dispensing volume requirements).

[0032] Specifically, the cup 21 includes a first sealing part 211 and a second sealing part 212 symmetrically arranged, which abut against the inner wall of the air chamber 11. The outer diameter of the sealing part abuts tightly against the inner wall of the air chamber, achieving complete isolation between the upper and lower chambers of the air chamber. This ensures that the pressure during air intake can be accurately transmitted to the cup, while also preventing air pressure leakage from causing the ejector pin to jam. A glue inlet channel 121 is provided on one side of the glue chamber 12. This glue inlet channel 121 is inclined downwards (e.g., at a 45° angle to the horizontal). The inclined design utilizes gravity to promote glue flow and prevents glue residue and solidification at the connection between the glue inlet channel and the glue chamber.

[0033] <Example 2> In this embodiment, the parts that are the same as in Embodiment 1 are given the same reference numerals, and the same text descriptions are omitted.

[0034] like Figure 7 As shown, compared to Embodiment 1, this embodiment provides a glue gun, including a gun base 7 and an anti-drip needle valve mechanism. The anti-drip needle valve mechanism is disposed on the side of the gun base 7, and the glue chamber 12 is connected to the glue supply channel 71 of the gun base 7. Glue enters the glue chamber through the glue supply channel and is then output through the glue outlet of the nozzle.

[0035] In this embodiment, the ejector pin uses two air inlets. By switching between different air inlets using a solenoid valve, the ejector pin is pushed up and pressed down. The sharp part at the end of the ejector pin and the conical hole inside the nozzle come into contact and separate, thus realizing the dispensing and cutting off of glue by the glue gun. Due to the short stroke and rapid glue cutting, compared with the traditional round-head ejector pin, the fit is higher, it is not easy to wear, and it can achieve virtually no dripping.

[0036] In the above embodiments one and two, during the working process, depending on the different working environments, some of the technical implementation methods of embodiments one and two can be combined or replaced.

[0037] The technical principles of this utility model have been described above in conjunction with specific embodiments. However, it should be noted that these descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, other specific embodiments or equivalent substitutions of this utility model that can be conceived by those skilled in the art without creative effort will all fall within the scope of protection of this utility model.

Claims

1. A drip-proof needle valve mechanism, characterized in that, The device includes an adapter block and a ejector pin disposed within the adapter block. The adapter block includes an air chamber and a glue chamber disposed below the air chamber. A leather cup is provided above the ejector pin and is disposed in the air chamber. The air chamber has a first air inlet and a second air inlet, which are located above and below the leather cup, respectively. A nozzle is provided below the adapter block, and the nozzle has a glue outlet. The ejector pin is inserted below the nozzle and is positioned corresponding to the glue outlet. When air enters through the first air inlet, the ejector pin presses down to close the glue outlet. When air enters through the second air inlet, the ejector pin moves upward and disengages from the glue outlet.

2. The anti-drip needle valve mechanism according to claim 1, characterized in that, The adapter block is provided with a valve seat, and an adjusting component is provided inside the valve seat. The adjusting component is movably connected to the valve seat and abuts against the ejector pin.

3. The anti-drip needle valve mechanism according to claim 2, characterized in that, The valve seat is provided with a threaded part, and the adjusting part is threadedly connected to the threaded part.

4. The anti-drip needle valve mechanism according to claim 1, characterized in that, One end of the ejector pin is provided with a tapered part, which is positioned opposite to the glue outlet hole, which is a tapered hole and corresponds to the tapered part.

5. The anti-drip needle valve mechanism according to claim 4, characterized in that, The conical part includes a tip and a frustum portion disposed between the tip and the ejector pin. The conical hole includes a first conical hole, a second conical hole, and a straight hole communicating with the second conical hole. When the ejector pin is pressed down to close the dispensing hole, the tip is inserted into the straight hole through the conical hole and fits against the second conical hole.

6. The anti-drip needle valve mechanism according to claim 1, characterized in that, One end of the adapter block is provided with a sleeve, and the sleeve is connected to the nozzle by fasteners.

7. The anti-drip needle valve mechanism according to claim 1, characterized in that, The leather cup includes a first sealing part and a second sealing part arranged symmetrically, and the first and second sealing parts abut against the inner wall of the air cavity.

8. The anti-drip needle valve mechanism according to claim 1, characterized in that, The first and second air inlets are connected to a solenoid valve, which switches the air intake between the first and second air inlets.

9. The anti-drip needle valve mechanism according to claim 1, characterized in that, The glue cavity has a glue inlet channel, which is inclined downwards.

10. A glue gun, comprising a gun base, characterized in that, Includes the anti-drip needle valve mechanism as described in any one of claims 1 to 9, wherein the anti-drip needle valve mechanism is disposed at the front end of the gun holder, and the glue cavity is connected to the glue supply channel of the gun holder.

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