Hot melt adhesive spray gun capable of conveniently adjusting adhesive outlet amount

Abstract

The utility model relates to the field of hot melt adhesive spraying equipment, in particular to a hot melt adhesive spray gun convenient to adjust the adhesive outlet amount, which comprises a shell, an adjusting seat, a valve seat, a sealing sleeve, an ejector pin and a piston, the shell comprises an adhesive inlet cavity and an adhesive outlet cavity, and the adjusting seat is arranged above the adhesive outlet cavity; the sealing sleeve is in threaded connection with the adjusting seat, a through receding hole is formed in the adjusting seat, and the receding hole is used for providing a receding space for rotating the sealing sleeve; the ejector pin is fixedly connected with the piston and penetrates through the sealing sleeve, the adjusting seat and the glue outlet cavity, a pin head of the ejector pin is positioned in the glue outlet cavity and is used for communicating or isolating the glue inlet cavity and the glue outlet cavity and sucking a glue solution in the glue spraying head into the glue outlet cavity when glue spraying is paused, so that the problem that the glue solution is easy to block the glue spraying head is solved; the piston can move up and down and is mounted in the valve seat; the ejector pin can move up and down along with the piston; the position of the piston abutting against the upper end of the sealing sleeve is changed by rotating the sealing sleeve so as to adjust the opening degree of the ejector pin, and the problem that a spray gun is frequently disassembled and assembled when the opening degree of the ejector pin is adjusted is solved.

Description

Technical Field

[0001] This utility model relates to the field of hot melt adhesive spraying equipment, and in particular to a hot melt adhesive spray gun that is easy to adjust the amount of adhesive dispensed. Background Technology

[0002] Hot melt adhesive spray guns are the core equipment in automated glue application processes. Their core function is to control the opening of the ejector pin to achieve the amount of adhesive dispensed. The ejector pin opening of traditional hot melt adhesive spray guns is usually adjusted in two ways: (1) Mechanical disassembly adjustment: the spray gun housing needs to be disassembled to manually adjust the position of the ejector pin, and then reassembled after adjustment. This method has the problems of long operation interruption time and repeated disassembly and assembly leading to increased wear of parts. (2) Indirect adjustment by transmission components: the ejector pin displacement is controlled by mechanical transmission systems such as gear sets and linkage mechanisms. Although this type of solution avoids frequent disassembly and assembly, it has the disadvantages of complex structure, high manufacturing cost, and difficult maintenance. In addition, when the spray gun stops working, the hot melt adhesive residue at the nozzle solidifies rapidly due to the temperature drop, forming solid glue blocks, which are very easy to block the glue flow channel. In the existing technology, glue is usually sprayed out by splashing or by physically squeezing out the blocked glue blocks before applying glue, which causes serious waste of glue, high frequency of machine shutdown for cleaning, and wear of parts affecting the glue application accuracy.

[0003] Therefore, there is an urgent need to develop a hot melt adhesive spray gun that allows for easy adjustment of the dispensing amount and convenient adjustment of the ejector pin opening, thereby solving the problem of adhesive clogging the spray nozzle when the spraying process is paused. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a hot melt adhesive spray gun that is easy to adjust the amount of adhesive dispensed.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] A hot melt adhesive spray gun with adjustable dispensing volume includes a housing, an adjusting seat, a valve seat, a sealing sleeve, a ejector pin, and a piston. The housing includes an inlet chamber and an outlet chamber. The adjusting seat is installed above the outlet chamber. The valve seat is installed above the adjusting seat. The sealing sleeve is threadedly connected to the adjusting seat. The adjusting seat has a through clearance hole to provide clearance space for rotating the sealing sleeve. The ejector pin is fixedly connected to the piston and passes through the sealing sleeve, the adjusting seat, and the outlet chamber. The tip of the ejector pin is located in the outlet chamber and is used to connect or isolate the inlet and outlet chambers. The piston is movable up and down and is installed in the valve seat. The ejector pin can move up and down with the piston. When the inlet and outlet chambers are isolated, the piston is in its initial position. When the piston moves downward from its initial position to abut against the upper end of the sealing sleeve, the ejector pin moves the maximum downward distance, and the inlet and outlet chambers are connected. By rotating the sealing sleeve, the position of the piston when it abuts against the upper end of the sealing sleeve is changed, thereby changing the maximum downward distance that the piston drives the ejector pin to move.

[0007] Preferably, the sealing sleeve is provided with several adjustment holes along the circumference, and the adjustment holes are located inside the relief hole.

[0008] Preferably, the bottom of the ejector pin tip is provided with a glue outlet groove, which is inclined downward toward the ejector pin axis.

[0009] Preferably, the housing also includes an air inlet chamber located below the glue inlet chamber, which is used to input heating gas to heat the housing.

[0010] Preferably, the air intake chamber is arranged in a serpentine shape.

[0011] Preferably, the device also includes a glue spray head, which is installed below the glue dispensing chamber. The glue spray head has a glue dispensing channel and several air dispensing channels inside, and the glue dispensing channel is connected to the glue dispensing chamber. The air dispensing channels are circumferentially arranged outside the glue dispensing channel and are connected to the air inlet chamber.

[0012] Preferably, the nozzle seat is also included. The inner side of the nozzle seat is provided with an annular venting groove. The outer radial direction of the end section of the spray head gradually decreases downward. Several air jet grooves are obliquely arranged along the circumference of the outer wall of the end section of the spray head. The nozzle seat is sleeved on the outside of the spray head. A venting chamber is formed between the venting groove and the outer wall of the middle section of the spray head. The venting chamber is connected to the air outlet channel. An air jet chamber is formed between the air jet groove and the inner wall below the venting groove of the nozzle seat. The air jet chamber is connected to the venting chamber.

[0013] Preferably, the system also includes a solenoid valve. The piston divides the internal space of the valve seat into an upper chamber and a lower chamber. The solenoid valve is used to control the amount of gas input into the upper and lower chambers to change the size of the upper and lower chambers and drive the piston to move up and down.

[0014] Preferably, an annular seal is provided between the piston and the valve seat.

[0015] Preferably, a return spring is also included, which provides a spring force for the piston to move toward the initial position. One end of the return spring is connected to the sealing sleeve, and the other end is connected to the piston.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] (1) The hot melt glue spray gun proposed in this utility model can directly rotate and adjust the sealing sleeve through the relief hole on the adjustment seat, so as to change the position of the piston in the valve seat when the upper end of the piston and the sealing sleeve abuts, thereby changing the maximum distance that the piston drives the ejector pin to move downward, realizing the adjustment of the ejector pin opening, controlling the glue output of the glue dispensing chamber, and the adjustment structure is simple and convenient.

[0018] (2) The hot melt glue spray gun proposed in this utility model is easy to adjust the glue output by setting the needle of the ejector pin in the glue outlet chamber. When the needle of the ejector pin moves upward to abut against the inlet of the glue outlet chamber, the space of the glue outlet chamber becomes larger and a negative pressure is generated, which draws the glue liquid that originally flowed into the glue outlet channel into the glue outlet chamber. When the spray gun stops working, it avoids the seepage of residual glue, so as to accurately control the glue cut-off of the spray gun and solve the problems of glue waste and glue easy to clog the spray nozzle.

[0019] (3) The hot melt glue spray gun proposed in this utility model is designed with a serpentine air inlet chamber below the glue inlet chamber of the housing and an airflow channel designed in the spray head. The heated gas enters the airflow channel after passing through the serpentine air inlet chamber. The temperature of the glue liquid in the glue inlet chamber, glue outlet chamber and glue outlet channel is maintained by heat transfer in the housing and the spray head, so that the glue material is kept in a liquid state and the glue liquid in the spray head solidifies and causes blockage.

[0020] (4) The hot melt glue spray gun proposed in this utility model is designed with a glue groove at the bottom of the needle of the ejector pin, so as to avoid the needle of the ejector pin blocking the glue outlet cavity when the opening of the ejector pin is large, so that the glue liquid cannot flow to the glue outlet channel.

[0021] (5) The hot melt glue spray gun proposed in this utility model has a spray head that is easy to adjust the amount of glue. Through the structural design of the spray head and nozzle seat, the gas sprayed from the air chamber will spirally pressurize the glue liquid, making the glue spraying more uniform and ensuring the glue spraying effect. Attached Figure Description

[0022] Figure 1 This is a cross-sectional schematic diagram of the overall structure of this utility model;

[0023] Figure 2 This is a cross-sectional schematic diagram of the air intake chamber of the housing of this utility model;

[0024] Figure 3 This is a schematic diagram of the overall structure of the glue spray head of this utility model;

[0025] Figure 4 This is a cross-sectional schematic diagram of the glue spray head of this utility model;

[0026] Figure 5 This is a schematic diagram of the nozzle seat of this utility model;

[0027] Reference numerals: 1. Housing; 11. Inlet cavity; 12. Outlet cavity; 13. Air inlet cavity; 2. Adjusting seat; 21. Clearance hole; 3. Valve seat; 31. Upper chamber; 32. Lower chamber; 4. Sealing sleeve; 41. Adjusting hole; 5. Ejector pin; 51. Needle; 52. Outlet groove; 61. Piston; 62. Annular seal; 63. Return spring; 7. Spray nozzle; 71. Outlet channel; 72. Outlet air channel; 73. Air jet groove; 8. Nozzle seat; 81. Vent groove; 9. Solenoid valve. Detailed Implementation

[0028] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. The accompanying drawings are merely illustrative to facilitate understanding of the present invention, and their specific proportions can be adjusted according to design requirements. The vertical relationships of relative elements and the definitions of front / back in the graphics described herein should be understood by those skilled in the art to refer to the relative positions of the components; therefore, they can all be flipped to present the same component, and all of this should fall within the scope disclosed in this specification.

[0029] refer to Figures 1 to 5 This application proposes a hot melt adhesive spray gun with easily adjustable dispensing volume, comprising a housing 1, an adjusting seat 2, a valve seat 3, a sealing sleeve 4, a ejector pin 5, a piston 61, a spray head 7, a nozzle seat 8, and a solenoid valve 9. The housing 1 includes an inlet chamber 11 and an outlet chamber 12. The adjusting seat 2 is installed above the outlet chamber 12, and the spray head 7 is installed below the outlet chamber 12. The nozzle seat 8 is sleeved on the outside of the spray head 7. The valve seat 3 is installed above the adjusting seat 2, and the valve seat 3 and the adjusting seat 2 are sealed together. The sealing sleeve 4 is threadedly connected to the adjusting seat 2. The adjusting seat 2 has a through clearance hole 21, which provides clearance space for rotating the sealing sleeve 4, so that the sealing sleeve 4 can be rotated without the need for... Disassemble the spray gun; the ejector pin 5 is fixedly connected to the piston 61 and passes through the sealing sleeve 4, the adjusting seat 2 and the dispensing chamber 12. The needle 51 of the ejector pin 5 is located in the dispensing chamber 12 and is used to connect or isolate the dispensing chamber 11 and the dispensing chamber 12. When the spray gun stops working, the needle 51 of the ejector pin 5 moves upward to abut against the inlet of the dispensing chamber 12 to isolate the dispensing chamber 11 and the dispensing chamber 12 and prevent the glue from continuing to flow out. Specifically, the upward movement of the ejector pin 5 makes the space of the dispensing chamber 12 larger, generating negative pressure, which draws the glue that originally flowed into the dispensing channel 71 into the dispensing chamber 12 to avoid the seepage of residual glue, so as to accurately control the dispensing of the spray gun and solve the problems of glue waste and glue clogging of the spray nozzle 7.

[0030] The piston 61 is movable up and down inside the valve seat 3. Specifically, the piston 61 divides the internal space of the valve seat 3 into an upper chamber 31 and a lower chamber 32. The solenoid valve 9 is used to control the amount of gas input into the upper chamber 31 and the lower chamber 32 to change the size of the upper chamber 31 and the lower chamber 32 and drive the piston 61 to move up and down. An annular seal 62 is provided between the piston 61 and the valve seat 3 to isolate the upper chamber 31 and the lower chamber 32. The ejector pin 5 can move up and down with the piston 61. When the glue inlet chamber 11 and the glue outlet chamber 12 are isolated, the position of the piston 61 is the initial position. When the piston 61 moves down from the initial position to the state where it abuts against the upper end of the sealing sleeve 4, the ejector pin 5 moves down the maximum distance. At this time, the glue inlet chamber 11 and the glue outlet chamber 12 are connected. The sealing sleeve 4 can be directly rotated through the relief hole 21 to change the position when the piston 61 abuts against the upper end of the sealing sleeve 4, so as to change the maximum distance that the piston 61 drives the ejector pin 5 to move down, thereby changing the opening of the ejector pin 5 to control the glue output of the glue outlet chamber 12. The adjustment structure is simple and convenient.

[0031] In a specific embodiment, the sealing sleeve 4 is provided with a plurality of adjustment holes 41 along the circumference, so that when the sealing sleeve 4 is rotated, force is applied to the adjustment holes 41 to drive the sealing sleeve 4 to rotate. Furthermore, the adjustment holes 41 are located inside the relief hole 21, so that when the sealing sleeve 4 is rotated, there is no need to disassemble the spray gun, and it is convenient to directly pass through the relief hole 21 to apply force to any one of the adjustment holes 41 to drive the sealing sleeve 4 to rotate.

[0032] In a specific embodiment, when the glue inlet chamber 11 and the glue outlet chamber 12 are isolated, the needle tip 51 of the ejector pin 5 abuts against the inlet of the glue outlet chamber 12; the bottom of the needle tip 51 of the ejector pin 5 is provided with a glue outlet groove 52, which is inclined downward toward the axis of the ejector pin 5 so that the glue liquid can flow from the glue outlet groove 52 to the glue outlet channel 71.

[0033] In a specific embodiment, the housing 1 further includes an air inlet chamber 13, located below the glue inlet chamber 11, for inputting heating gas to heat the housing 1; Reference Figure 2 The air inlet chamber 13 is arranged in a serpentine pattern to increase the heat exchange efficiency between the introduced heated gas and the housing 1, thereby maintaining the temperature of the adhesive liquid in the adhesive inlet chamber 11. Further, refer to... Figure 1 , Figure 3 and Figure 4 The spray nozzle 7 is provided with a glue outlet channel 71 and several air outlet channels 72. The glue outlet channel 71 is connected to the glue outlet chamber 12. The air outlet channels 72 are arranged circumferentially outside the glue outlet channel 71 and are connected to the air inlet chamber 13. The heated gas enters the air outlet channel 72 after passing through the serpentine air inlet chamber 13. The temperature of the glue liquid in the glue inlet chamber 11, glue outlet chamber 12 and glue outlet channel 71 is maintained by heat transfer in the housing 1 and the spray nozzle 7, so that the glue material is kept in a liquid state and the glue liquid in the spray nozzle 7 is prevented from solidifying and causing blockage.

[0034] In a specific embodiment, refer to Figure 1 , Figure 3 and Figure 5 The nozzle seat 8 has an annular venting groove 81 on its inner side. The outer radial direction of the end section of the spray head 7 gradually decreases downwards. Several air jet grooves 73 are obliquely arranged circumferentially on the outer wall of the end section of the spray head 7. Specifically, the end section of the spray head 7 is a truncated cone. The inner side of the nozzle seat 8 is provided with a truncated cone cavity that matches the spray head 7. The truncated cone cavity is located below the venting groove 81. The nozzle seat 8 is fitted onto the outer side of the spray head 7. A venting chamber is formed between the venting groove 81 and the outer wall of the middle section of the spray head 7. The venting chamber is connected to the air outlet channel 72. An air jet chamber is formed between the air jet grooves 73 and the truncated cone cavity below the venting groove 81 of the nozzle seat 8. The air jet chamber is connected to the venting chamber. Through the structural design of the spray head 7 and the nozzle seat 8, the gas ejected from the air jet chamber forms a spiral airflow, which spirally pressurizes the adhesive, resulting in more uniform spraying and ensuring the spraying effect.

[0035] In a specific embodiment, the return spring 63 is used to provide elastic force for the piston 61 to move toward the initial position. One end of the spring is connected to the sealing sleeve 4, and the other end is connected to the piston 61.

[0036] The following describes a specific working process to further illustrate the hot melt adhesive spray gun proposed in this application, which facilitates the adjustment of adhesive output.

[0037] When no glue is being applied, the air supply mechanism does not supply gas to the upper chamber 31 and lower chamber 32 within the valve seat 3. The piston 61 moves upward to its initial position under the action of the return spring 63. At this time, the ejector pin 5 moves upward under the drive of the piston 61, causing the needle tip 51 of the ejector pin 5 to abut against the inlet of the glue outlet chamber 12, isolating the glue inlet chamber 11 and the glue outlet chamber 12. The glue inlet chamber 11 cannot supply glue to the glue outlet chamber 12. When glue application is required, the air supply mechanism supplies air to the upper chamber 31 within the valve seat 3, increasing... The increased space in the upper chamber 31 reduces the space in the lower chamber 32, causing the piston 61 to move downwards. At this time, the ejector pin 5 moves downwards under the influence of the piston 61, connecting the glue inlet chamber 11 and the glue outlet chamber 12. The glue inlet chamber 11 supplies glue to the glue outlet chamber 12 for spraying. Simultaneously, the air supply mechanism inputs heating gas into the air inlet chamber 13. The heating gas passes sequentially through the air inlet chamber 13 and the air outlet passage 72 to maintain the temperature of the glue in the glue inlet chamber 11 and the spray head 7, preventing the glue from solidifying and clogging. Furthermore, before spraying, the nozzle seat 8 is fitted onto the outside of the spray head 7. After the heating gas flows out from the air outlet passage 72, it sequentially enters the ventilation chamber and the air jet chamber, spraying out a spiral airflow to spirally pressurize the glue, ensuring the spraying effect.

[0038] When it is necessary to stop spraying glue, the air supply mechanism supplies air to the lower chamber 32 in the valve seat 3 and depressurizes the upper chamber 31. Under the action of the gas change in the upper chamber 31 and the lower chamber 32 and the return spring 63, the piston 61 moves upward quickly to the initial position. The ejector pin 5 also moves upward quickly under the drive of the piston 61, so that the needle tip 51 of the ejector pin 5 moves upward and abuts against the inlet of the glue outlet chamber 12. As the ejector pin 5 moves upward, the space of the glue outlet chamber 12 becomes larger, generating negative pressure, which draws the glue that originally flowed into the glue outlet channel 71 into the glue outlet chamber 12, avoiding the seepage of residual glue, preventing glue tailing, stopping the glue spraying, and achieving precise control of the glue cut-off of the spray gun.

[0039] When the dispensing volume needs to be adjusted, the sealing sleeve 4 can be rotated directly through the clearance hole 21 of the adjusting seat 2, causing the sealing sleeve 4 to move upward or downward. Furthermore, the sealing sleeve 4 can be rotated by applying force through the adjusting hole 41 on the sealing sleeve 4, making adjustment convenient and eliminating the need to disassemble the spray gun. The amount of movement of the sealing sleeve 4 can be directly controlled and observed through the clearance hole 21, thereby changing the position of the piston 61 when it abuts against the upper end of the sealing sleeve 4, and thus changing the maximum distance that the piston 61 drives the ejector pin 5 to move downward, thereby changing the opening of the ejector pin 5 to control the dispensing volume. This is convenient and practical, overcoming the drawbacks of traditional ejector pin 5 opening adjustment methods, such as frequent disassembly and assembly, complex structure, high manufacturing cost, and difficult maintenance.

[0040] The above embodiments are only used to further illustrate the technical solution of this utility model, but this utility model is not limited to the embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this utility model shall fall within the protection scope of the technical solution of this utility model.

Claims

1. A hot melt adhesive spray gun with easily adjustable dispensing volume, characterized in that: The device includes a housing, an adjusting seat, a valve seat, a sealing sleeve, a ejector pin, and a piston. The housing includes an inlet cavity and an outlet cavity. The adjusting seat is mounted above the outlet cavity. The valve seat is mounted above the adjusting seat. The sealing sleeve is threadedly connected to the adjusting seat. The adjusting seat has a through clearance hole to provide clearance space for rotating the sealing sleeve. The ejector pin is fixedly connected to the piston and passes through the sealing sleeve, the adjusting seat, and the outlet cavity. The tip of the ejector pin is located in the outlet cavity, used to connect or isolate the inlet cavity and the outlet cavity. The piston is movable up and down and is mounted inside the valve seat. The ejector pin can move up and down with the piston. When the inlet cavity and the outlet cavity are isolated, the piston is in its initial position. When the piston moves downward from its initial position to abutting the upper end of the sealing sleeve, the ejector pin moves downward to its maximum distance, and the glue inlet chamber and glue outlet chamber are connected. By rotating the sealing sleeve, the position of the piston when it abuts the upper end of the sealing sleeve is changed, thereby changing the maximum distance that the piston drives the ejector pin to move downward.

2. The hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 1, characterized in that: The sealing sleeve is provided with a plurality of adjustment holes along the circumference, and the adjustment holes are located inside the clearance holes.

3. The hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 1, characterized in that: The bottom of the needle tip of the ejector pin is provided with a glue outlet groove, which is inclined downward toward the axis of the ejector pin.

4. A hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 1, characterized in that: The housing also includes an air inlet chamber located below the glue inlet chamber, which is used to input heating gas to heat the housing.

5. A hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 4, characterized in that: The air intake chamber is arranged in a serpentine shape.

6. A hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 4, characterized in that: It also includes a glue spray head, which is installed below the glue dispensing chamber. The glue spray head has a glue dispensing channel and several air dispensing channels inside. The glue dispensing channel is connected to the glue dispensing chamber. The air dispensing channels are circumferentially arranged outside the glue dispensing channel and are connected to the air inlet chamber.

7. A hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 6, characterized in that: It also includes a nozzle seat, the inner side of which is provided with an annular venting groove. The outer radial direction of the end section of the spray head gradually decreases downward. The outer wall of the end section of the spray head has several air jet grooves obliquely arranged circumferentially. The nozzle seat is sleeved on the outside of the spray head. A venting chamber is formed between the venting groove and the outer wall of the middle section of the spray head. The venting chamber is connected to the air outlet channel. An air jet chamber is formed between the air jet groove and the inner wall below the venting groove of the nozzle seat. The air jet chamber is connected to the venting chamber.

8. A hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 1, characterized in that: It also includes a solenoid valve, wherein the piston divides the internal space of the valve seat into an upper chamber and a lower chamber. The solenoid valve is used to control the amount of gas input into the upper chamber and the lower chamber, so as to change the size of the upper chamber and the lower chamber and drive the piston to move up and down.

9. A hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 1, characterized in that: An annular seal is provided between the piston and the valve seat.

10. A hot melt adhesive spray gun with easily adjustable dispensing volume according to claim 1, characterized in that: It also includes a return spring, which provides a spring force for the piston to move toward the initial position. One end of the return spring is connected to the sealing sleeve, and the other end is connected to the piston.

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