Spraying system

Abstract

The utility model relates to the technical field of spraying, and particularly discloses a spraying system which comprises a spraying head, a liquid storage device, a liquid supply branch, a gas supply branch and a power assembly. Wherein the liquid storage device is used for containing spraying liquid; the liquid supply branch is connected between the spray head and the liquid storage device, and a flow detection device used for detecting the flow of liquid in the liquid supply branch and a first valve used for controlling the liquid supply branch to be connected and disconnected are arranged in the liquid supply branch; the air supply branch is connected to the spray head and used for being connected with an air source, and a first adjusting valve used for adjusting the air supply amount and a second valve used for controlling on-off of the air supply branch are arranged in the air supply branch; the power assembly is connected to the liquid storage device and used for conveying the spraying liquid in the liquid storage device to the spray head through the liquid supply branch. The spraying system is not influenced by the change or fluctuation of the liquid level of the sprayed liquid, the stability is high, and the spraying amount can be controlled.

Description

Technical Field

[0001] The utility model relates to the technical field of spraying, and more specifically to a spraying system. Background Art

[0002] Printed circuit boards (PCBs) and components are mostly soldered using wave soldering equipment. Wave soldering equipment is an automated assembly line operation mode. The PCB does not stop halfway on the assembly line. The soldering is completed through four steps: flux spraying, preheating, wave soldering, and cooling. The flux spraying is done by using a spraying system. The flux nozzle of the spraying system sprays the flux evenly on the bottom of the PCB to clean the pads on the PCB. The amount of flux spraying will directly affect the soldering results of PCB products. If the flux is sprayed excessively, there will be flux residue after soldering, the PCB board will be very dirty, and the flux will be wasted. If the amount of flux spraying is insufficient, the tinning effect is not good, and it is easy to produce soldering defects such as cold soldering and continuous soldering, resulting in poor soldering. Therefore, quantitative control of flux spraying can greatly improve the soldering quality of PCB products and reduce unnecessary scrap or rework.

[0003] In the process of implementing this application, the inventors found that there are at least the following problems in the prior art:

[0004] In the current spraying system, gravity supply is used for liquid supply. The gravity supply method is to lift or place the liquid raw material to a position higher than the PCB spraying position, and use the potential energy of the liquid to flow from a high position to a low position to supply liquid to the relatively low nozzle for spraying. The gravity supply method will cause different spraying amounts due to the height of the liquid placement, and during the spraying process, the liquid level will continue to change, resulting in unstable liquid supply output. The fluctuation of the spraying amount will affect the welding quality of PCB products. Utility Model Content

[0005] In view of this, an object of the present invention is to provide a spraying system, the structural design of which can effectively solve the problem of fluctuation in spraying amount.

[0006] In order to achieve the above object, the utility model provides the following technical solutions:

[0007] A spraying system, comprising:

[0008] Sprinklers;

[0009] A liquid storage device, used for containing spraying liquid;

[0010] A liquid supply branch connected between the nozzle and the liquid storage device, wherein the liquid supply branch is provided with a flow detection device for detecting the liquid flow in the liquid supply branch and a first valve for controlling the on-off of the liquid supply branch;

[0011] An air supply branch connected to the nozzle and used to be connected to an air source, wherein a first regulating valve for regulating the air supply volume and a second valve for controlling the on-off of the air supply branch are provided in the air supply branch;

[0012] The power assembly is connected to the liquid storage device and is used to transport the spraying liquid in the liquid storage device to the spray head through the liquid supply branch.

[0013] Optionally, in the above-mentioned spraying system, the power component includes a liquid supply pump arranged in the liquid supply branch.

[0014] Optionally, in the above-mentioned spraying system, a first pressure stabilizing device is further provided in the liquid supply branch, and the first pressure stabilizing device is provided between the liquid supply pump and the first valve;

[0015] The first pressure stabilizing device is provided with a first pressure detecting device for detecting pressure.

[0016] Optionally, in the above-mentioned spraying system, the overflow port of the first pressure stabilizing device is connected to the inlet of the liquid storage device.

[0017] Optionally, in the above-mentioned spraying system, the liquid storage device is a pressure tank, the power assembly includes a boost branch connected between the pressure tank and the air source, and the boost branch is provided with a second regulating valve for adjusting the air supply.

[0018] Optionally, the above-mentioned spraying system further includes a second pressure detection device connected to the outlet of the pressure tank and used to detect the outlet pressure of the pressure tank.

[0019] Optionally, in the above-mentioned spraying system, a tee is provided in the liquid supply branch, a first interface and a second interface of the tee are respectively connected to the first valve and the pressure tank, and a third interface of the tee is connected to the second pressure detection device.

[0020] Optionally, in the above-mentioned spraying system, the liquid supply branch is provided with a second pressure stabilizing device, and is connected to the spray head through the second pressure stabilizing device.

[0021] Optionally, in the above-mentioned spraying system, a third pressure stabilizing device is provided in the air supply branch, and the third pressure stabilizing device is provided between the second valve and the first regulating valve.

[0022] Optionally, the above-mentioned spraying system further includes an alarm device connected to the flow detection device, and the alarm device is used to output an alarm when the flow rate detected by the flow detection device is greater than a preset value.

[0023] The spraying system provided by the utility model comprises a spray head, a liquid storage device, a liquid supply branch, an air supply branch and a power assembly. The liquid storage device is used to hold the spraying liquid; the liquid supply branch is connected between the spray head and the liquid storage device, and a flow detection device for detecting the liquid flow in the liquid supply path and a first valve for controlling the on-off of the liquid supply branch are arranged in the liquid supply branch; the air supply branch is connected to the spray head, and the air supply branch is used to connect to the air source, and a first regulating valve for adjusting the air supply amount and a second valve for controlling the on-off of the air supply branch are arranged in the air supply branch; the power assembly is connected to the liquid storage device, and is used to transport the spraying liquid in the liquid storage device to the spray head through the liquid supply branch.

[0024] In the spraying system provided by the utility model, the liquid supply branch cooperates with the air supply branch, the liquid supply branch is used to provide spraying liquid, and through the setting of the power component, the spraying liquid in the liquid storage device can be transported to the nozzle, and the flow rate of the spraying liquid can be detected in real time through the flow detection device. The power component can provide stable power, so the flow rate of the spraying liquid is stable and controllable, thereby realizing quantitative spraying of the spraying liquid. In summary, the spraying system is not affected by the change or fluctuation of the liquid level of the spraying liquid, has high stability, and can control the spraying amount. That is, the spraying system can provide a suitable and stable spraying amount, which can ensure the welding quality of the PCB when applied to flux spraying, greatly reduce the product defective rate, and improve the intelligence level of the wave soldering equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 This is a structural schematic diagram of a spraying system according to a specific embodiment of the utility model;

[0027] Figure 2 It is a structural schematic diagram of a spraying system according to another specific embodiment of the utility model.

[0028] Reference numerals:

[0029] 1-nozzle; 2-liquid storage device; 3-liquid supply branch; 4-air supply branch; 51-liquid supply pump; 52-boosting branch;

[0030] 31-flow detection device; 32-first valve; 33-first pressure stabilizing device; 34-first pressure detection device; 35-second pressure detection device; 36-three-way valve; 37-second pressure stabilizing device;

[0031] 41-first regulating valve; 42-second valve; 43-third pressure stabilizing device;

[0032] 521-Second regulating valve. DETAILED DESCRIPTION

[0033] The utility model discloses a spraying system to control the spraying amount of soldering flux, reduce the defective rate of PCB products caused by excessive or insufficient soldering flux spraying, and improve the welding quality of PCB products.

[0034] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0035] The spraying system provided in this application is applicable to but not limited to the flux spraying in the field of SMT (Surface Mounted Technology) welding. Conventional flux spraying adopts gravity liquid supply, and the spraying amount is uncontrollable, which easily leads to excessive or insufficient flux spraying. The PCB with poor spraying continues to flow to the subsequent preheating, wave soldering, and cooling steps, until the final manual inspection to find that the welding quality is poor, and at this time the welding equipment has produced a large number of poor PCB products, and the treatment methods of poor products are usually the following: 1. The product is directly scrapped; 2. Manual rework, due to the inconsistent manual operation techniques, it is also difficult to ensure the quality of the solder joints; 3. Secondary wave soldering, which is easy to cause mechanical damage and thermal shock to the components of the PCB machine, leading to failure. It can be seen that both manual inspection and secondary welding are difficult to achieve the expected results, and for PCB products with extremely high requirements for solder joint quality, secondary welding rework is not accepted. Therefore, it can only be scrapped, and the losses caused are very huge.

[0036] In order to at least partially solve the defects of the above-mentioned spraying system, the present application provides a quantitative spraying system, which can control the spraying amount of flux and reduce the defective rate of PCB products caused by excessive or insufficient spraying of flux.

[0037] In some embodiments, the spraying system provided in the present application includes a spray head, a liquid storage device, a liquid supply branch, an air supply branch and a power assembly. Among them, the structure of the spray head can refer to the spray head structure setting in a conventional spraying system, and is not specifically limited here. The liquid storage device is used to hold the spraying liquid, and its specific shape can be set as needed. The liquid supply branch is connected between the spray head and the liquid storage device, and a flow detection device for detecting the liquid flow in the liquid supply path and a first valve for controlling the on-off of the liquid supply branch are provided in the liquid supply branch. The liquid supply branch can specifically adopt a hard or soft pipeline, or a channel formed by a structure such as a shell. The flow detection device and the first valve are respectively arranged in the pipeline or channel of the liquid supply. When the first valve is opened, the power assembly can transport the spraying liquid in the liquid storage device to the spray head through the flow detection device. The air supply branch is connected to the spray head, and the air supply branch is used to connect to the air source. The air supply branch is provided with a first regulating valve for adjusting the air supply amount and a second valve for controlling the on-off of the air supply branch. The air supply branch can be a hard or soft pipeline, or a channel formed by a shell or other structure. The first regulating valve and the second valve are arranged in the pipeline or channel of the air supply. When the second valve is opened, the gas provided by the gas source can be delivered to the nozzle through the first regulating valve. The power assembly is connected to the liquid storage device, and is used to deliver the spraying liquid in the liquid storage device to the nozzle through the liquid supply branch. The power assembly is a power device for delivering the spraying liquid. Unlike the conventional gravity supply of the spraying liquid, the power assembly can provide power for the spraying liquid in the liquid storage device to deliver it to the nozzle. The flow rate of the spraying liquid can be controlled by controlling the output power of the power assembly. The gas is output according to the amount after being adjusted by the first regulating valve, and enters the nozzle when the second valve is connected. The nozzle sprays the required amount of flux through the quantitative ratio of gas and liquid.

[0038] In the spraying system provided by the utility model, the liquid supply branch cooperates with the air supply branch, the liquid supply branch is used to provide spraying liquid, and through the setting of the power component, the spraying liquid in the liquid storage device can be transported to the nozzle, and the flow rate of the spraying liquid can be detected in real time through the flow detection device. The power component can provide stable power, so the flow rate of the spraying liquid is stable and controllable, thereby realizing quantitative spraying of the spraying liquid. In summary, the spraying system is not affected by the change or fluctuation of the liquid level of the spraying liquid, has high stability, and can control the spraying amount. That is, the spraying system can provide a suitable and stable spraying amount, which can ensure the welding quality of the PCB when applied to flux spraying, can greatly improve the yield rate, and enhance the intelligence level of the wave soldering equipment.

[0039] In some embodiments, see Figure 1 The power assembly includes a liquid supply pump 51 disposed in the liquid supply branch 3. That is, the liquid supply pump 51 is provided to pump the spraying liquid in the liquid storage device 2 to the nozzle 1. The through hole controls the rotation speed of the liquid supply pump 51 to adjust the flow rate of the spraying liquid, thereby realizing flow-controllable spraying.

[0040] In some embodiments, a first pressure stabilizing device 33 is further provided in the liquid supply branch 3, and the first pressure stabilizing device 33 is provided between the liquid supply pump 51 and the first valve 32. The first pressure stabilizing device 33 is provided to buffer the influence of the spraying liquid fluctuation. The first pressure stabilizing device 33 can be specifically a pressure stabilizing bottle.

[0041] In some embodiments, the first pressure stabilizing device 33 is provided with a first pressure detecting device 34 for detecting pressure. The first pressure detecting device 34 detects the pressure value of the liquid at the outlet of the liquid supply pump 51 in real time. When the pressure value deviates from the set value, the speed of the liquid supply pump 51 is controlled and adjusted to return the pressure value to the set value, forming a pressure closed loop to ensure the stable delivery of the spraying liquid such as flux. The first pressure detecting device 34 can specifically be a pressure sensor.

[0042] In some embodiments, the overflow port of the first voltage stabilizing device 33 is connected to the inlet of the liquid storage device 2. The rotation speed of the liquid supply pump 51 is set according to the spraying amount of the spraying liquid such as flux, and the liquid supply pump 51 extracts the spraying liquid from the liquid storage device 2. When the first valve 32 is in the passage state, the spraying liquid reaches the nozzle 1 through the flow detection device 31. When the first valve 32 is in the open state, the spraying liquid can flow back to the liquid storage device 2, thereby improving the safety and reliability of the system.

[0043] Specifically, the liquid storage device 2 can be a liquid storage barrel, the liquid supply pump 51 can be a gear pump, the first valve 32 and the second valve 42 can both be solenoid valves, the flow detection device 31 can be an electronic flow meter, and the first regulating valve 41 can be an electrical proportional valve.

[0044] In some embodiments, see Figure 2 , the liquid storage device 2 is a pressure tank, and the power assembly includes a boost branch 52 connected between the pressure tank and the air source, and a second regulating valve 521 for adjusting the air supply is provided in the boost branch 52. Different from the above-mentioned power assembly using the liquid supply pump 51, in this embodiment, the power assembly uses the boost branch 52, that is, the air supply of the air source is used to adjust the pressure in the pressure tank, thereby controlling the flow rate of the spraying liquid in the pressure tank. Specifically, the air source for supplying air to the power assembly and the air source for supplying air to the air supply branch 4 can be shared, thereby simplifying the structure. The pressure value of the pressure tank is set according to the spraying amount of the spraying liquid, and the intake air adjusts the flow rate through the first regulating valve 41 to provide gas to the pressure tank to ensure the pressure. When the first valve 32 is in the passage state, the spraying liquid reaches the nozzle 1 through the flow detection device 31. The second regulating valve 521 can specifically adopt an electrical proportional valve.

[0045] In some embodiments, the spraying system further includes a second pressure detection device 35 connected to the outlet of the pressure tank for detecting the outlet pressure of the pressure tank. The second pressure detection device 35 collects the liquid pressure value at the outlet of the pressure tank in real time. When the pressure value deviates from the set value, the pressure value is returned to the set value by controlling and adjusting the air intake pressure of the pressure tank, thereby forming a pressure closed loop to ensure the stable delivery amount of the spraying liquid. The first pressure detection device 34 can specifically be a pressure sensor.

[0046] In some embodiments, a tee 36 is provided in the liquid supply branch 3, the first interface and the second interface of the tee 36 are connected to the first valve 32 and the pressure tank respectively, and the third interface of the tee 36 is connected to the second pressure detection device 35. By providing the tee 36, the connection of the second pressure detection device 35 is facilitated.

[0047] In some embodiments, see Figure 1 , the liquid supply branch 3 is provided with a second voltage stabilizer 37, and is connected to the nozzle 1 through the second voltage stabilizer 37. That is, the second voltage stabilizer 37 is arranged at the rear end of the liquid supply branch 3, and the spraying liquid finally enters the nozzle 1 after passing through the second voltage stabilizer 37 in the liquid supply branch 3. Specifically, the second voltage stabilizer 37 is arranged between the flow detection device 31 and the nozzle 1. The second voltage stabilizer 37 can buffer the influence of liquid fluctuations and further ensure the stability of the system. The second voltage stabilizer 37 can specifically adopt a voltage stabilizer bottle.

[0048] In some embodiments, see Figure 1 or Figure 2 A third pressure stabilizing device 43 is provided in the gas supply branch 4, and the third pressure stabilizing device 43 is provided between the second valve 42 and the first regulating valve 41. The third pressure stabilizing device 43 can buffer the impact of gas fluctuations and further ensure the stability of the system. The third pressure stabilizing device 43 can specifically adopt a pressure stabilizing tank.

[0049] In some embodiments, the spraying system further includes an alarm device connected to the flow detection device 31, and the alarm device is used to output an alarm when the flow detected by the flow detection device 31 is greater than a preset value. By setting up the alarm device, relevant personnel can be reminded of abnormal flow so that emergency measures can be taken, further ensuring the reliability of spraying.

[0050] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0051] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A spraying system, characterized in that: include: Nozzle (1); A liquid storage device (2), used for containing the spraying liquid; A liquid supply branch (3) connected between the nozzle (1) and the liquid storage device (2), wherein the liquid supply branch (3) is provided with a flow detection device (31) for detecting the flow of liquid in the liquid supply branch and a first valve (32) for controlling the on-off of the liquid supply branch (3); An air supply branch (4) connected to the nozzle (1), and the air supply branch (4) is used to be connected to an air source, and the air supply branch (4) is provided with a first regulating valve (41) for regulating the air supply volume and a second valve (42) for controlling the on-off of the air supply branch (4); A power assembly is connected to the liquid storage device (2) and is used to transport the spraying liquid in the liquid storage device (2) to the spray head (1) via the liquid supply branch (3).

2. The spraying system according to claim 1, characterized in that: The power assembly comprises a liquid supply pump (51) arranged in the liquid supply branch (3).

3. The spraying system according to claim 2, characterized in that: A first pressure stabilizing device (33) is also provided in the liquid supply branch (3), and the first pressure stabilizing device (33) is provided between the liquid supply pump (51) and the first valve (32); The first pressure stabilizing device (33) is provided with a first pressure detecting device (34) for detecting pressure.

4. The spraying system according to claim 3, characterized in that: The overflow port of the first pressure stabilizing device (33) is in communication with the inlet port of the liquid storage device (2).

5. The spraying system according to claim 1, characterized in that: The liquid storage device (2) is a pressure tank, the power assembly comprises a pressurizing branch (52) connected between the pressure tank and the gas source, and a second regulating valve (521) for regulating the gas supply volume is provided in the pressurizing branch (52).

6. The spraying system according to claim 5, characterized in that: It also includes a second pressure detection device (35) connected to the outlet of the pressure tank and used to detect the outlet pressure of the pressure tank.

7. The spraying system according to claim 6, characterized in that: A tee (36) is provided in the liquid supply branch (3), a first interface and a second interface of the tee (36) are respectively connected to the first valve (32) and the pressure tank, and a third interface of the tee (36) is connected to the second pressure detection device (35).

8. The spraying system according to any one of claims 1 to 7, characterized in that: The liquid supply branch (3) is provided with a second pressure stabilizing device (37), and is connected to the nozzle (1) via the second pressure stabilizing device (37).

9. The spraying system according to any one of claims 1 to 7, characterized in that: A third pressure stabilizing device (43) is provided in the gas supply branch (4), and the third pressure stabilizing device (43) is provided between the second valve (42) and the first regulating valve (41).

10. The spraying system according to any one of claims 1 to 7, characterized in that: It also comprises an alarm device connected to the flow detection device (31), the alarm device being used to output an alarm when the flow detected by the flow detection device (31) is greater than a preset value.

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