A water jet diversion structure

Abstract

The present invention discloses a water jet diversion structure, which adopts a diversion cavity with a proportionally reduced cross-section, and at the same time, evenly distributed diversion holes are arranged on the bottom surface of the diversion cavity, and the cross-sectional area S1 of the first end surface of the diversion cavity is equal to the cumulative cross-sectional area S3 of all the diversion holes, so that the flow cross-section and flow rate of the fluid in the diversion cavity change in equal proportion, ensuring that the flow velocity of the fluid in the diversion cavity remains unchanged, so that the pressure of the fluid in the diversion cavity tends to be consistent, and an equal amount of fluid will evenly pass through each diversion hole, so as to achieve uniform diversion and improve the overall uniformity of circuit board processing; further, the working surface of the surge cavity is configured as a fully open working surface or a semi-open working surface according to the characteristics of the fluid and the circuit board equipment, so as to accurately control the flow rate and pressure of the fluid released to the circuit board.

Description

Technical Field

[0001] The invention relates to the technical field of circuit boards, and in particular to a water jet shunt structure of a circuit board. Background Art

[0002] In the production process of circuit boards, a variety of chemical treatment processes are required, and treatment equipment containing chemical solutions will be used. In the working tank of these equipment, a water jet is usually set on the top of the circuit board to spray the chemical solution on the circuit board through the water jet to enhance the treatment effect of the solution. This water jet split processing equipment includes an equipment body and a water jet split structure.

[0003] A Chinese patent with announcement number CN 217283645 U discloses a special water jet for browning circuit boards, which includes a water jet main body, a cavity formed inside the water jet main body along its length direction, a water inlet connected to the cavity is opened at one end of the water jet main body, a water spray main body is provided at the bottom of the water jet main body along its length direction, and a plurality of rows of water outlet channels connected to the cavity are provided at the bottom of the water jet main body.

[0004] The water jet disclosed in the above scheme and the common water jet in the prior art are as follows Figures 1a to 1c As shown, the cavity 1' is a rectangular cavity with a constant cross-section along the length direction of the water jet body. The fluid enters the cavity from the water inlet 2'. During the process of flowing through the length direction of the cavity 1', the pressure of the fluid will gradually decrease, resulting in inconsistent pressure and flow rate of the fluid entering each water outlet channel 3', resulting in uneven diversion, causing uneven treatment effect of the fluid on the surface of the circuit board, which has an adverse effect on the appearance and quality of the circuit board.

[0005] Therefore, how to make the water jet effectively distribute the fluid evenly and improve the overall uniformity of circuit board processing has become an urgent problem to be solved in this field. Summary of the invention

[0006] In view of the defects of the prior art, an object of the present invention is to provide a water jet flow diversion structure with uniform flow diversion and consistent internal fluid pressure.

[0007] In order to achieve the above object, the present invention provides a water jet flow splitting structure, which comprises

[0008] A flow dividing cavity, wherein the flow dividing cavity is defined by a bottom surface, a peripheral surface, a first end surface and a second end surface to form a closed cavity;

[0009] A plurality of diversion holes arranged on the bottom surface;

[0010] an inlet pipe disposed on the first end surface, the inlet pipe introducing the working fluid into the diversion cavity, and

[0011] A surge cavity is arranged below the diversion cavity, and the surge cavity is connected with the diversion cavity through the plurality of diversion holes.

[0012] Among them, the cross-section of the diverter cavity defined by the peripheral surface and the bottom surface decreases proportionally from the first end surface to the second end surface along the length direction of the diverter cavity, the diverter holes are evenly distributed equidistantly along the length direction of the diverter cavity, and the cross-sectional area S1 of the first end surface of the diverter cavity is equal to the cumulative cross-sectional area S3 of all the diverter holes.

[0013] Furthermore, the inclined angle θ of the diversion cavity is

[0014]

[0015] Wherein, L is the length of the diverter cavity, w is the width of the diverter cavity, R is the radius of the diverter hole, and n is the total number of the diverter holes.

[0016] Furthermore, surge walls for limiting the flow range of the working liquid are provided on both sides of the surge chamber.

[0017] Furthermore, the bottom surface of the surge chamber and the circuit board cooperates to form a fully open working surface or a semi-open working surface.

[0018] Furthermore, a plurality of long strip-shaped notches are evenly distributed on the semi-open working surface of the flow chamber.

[0019] Furthermore, the total cross-sectional area of ​​all the long strip-shaped notches is equal to or greater than the cumulative cross-sectional area S3 of all the diversion holes.

[0020] Furthermore, a plurality of small holes are evenly distributed on the semi-open working surface of the flow chamber.

[0021] Furthermore, the total cross-sectional area of ​​all the small holes is ≤ the cumulative cross-sectional area S3 of all the diversion holes.

[0022] Furthermore, two ends of the surge chamber are provided with connectors for detachably connecting with the circuit board equipment.

[0023] Furthermore, the connecting piece is composed of a latch.

[0024] The water jet diversion structure and circuit board equipment provided by the present invention cleverly adopt a diversion cavity with a proportionally reduced cross section, and compensate for the pressure drop along the length direction of the diversion cavity by reducing the cross section in proportion. At the same time, evenly distributed diversion holes are arranged on the bottom surface of the diversion cavity, and the cross-sectional area S1 of the first end surface of the diversion cavity is equal to the cumulative cross-sectional area S3 of all the diversion holes. The common correlation of these features makes the flow cross section and flow rate of the fluid in the diversion cavity change in proportion, ensuring that the flow velocity of the fluid in the diversion cavity remains unchanged, so that the pressure of the fluid in the diversion cavity tends to be consistent, so that an equal amount of fluid will pass through each diversion hole evenly, thereby achieving uniform diversion and improving the overall uniformity of circuit board processing. Furthermore, the working surface of the surge cavity is configured as a fully open working surface or a semi-open working surface according to the characteristics of the fluid and the circuit board equipment, so as to accurately control the flow rate and pressure of the fluid released to the circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0026] Figure 1a to Figure 1c It is a schematic diagram of the structure of a water jet in the prior art;

[0027] Figure 2a to Figure 2c They are respectively a bottom view, a front view and a cross-sectional view of the water jet diversion structure of the present invention;

[0028] Figure 3 Schematic diagram of the diverter hole structure of Example 1 of the present invention;

[0029] Figure 4 It is a cross-sectional view and fluid flow diversion schematic diagram of the first embodiment of the present invention;

[0030] Figure 5 for Figure 4 A magnified view of the local structure;

[0031] Figure 6 It is a schematic diagram of the overall structure of the first embodiment of the present invention;

[0032] Figure 7 It is a cross-sectional view of the flow diversion cavity and the surge cavity of the first embodiment of the present invention;

[0033] Figure 8 Schematic diagram of the structure of the diversion cavity in the first embodiment of the present invention;

[0034] Figures 9a to 9c They are respectively a bottom view, a front view and a cross-sectional view of the second embodiment of the water jet diversion structure in the present invention;

[0035] Fig.10 This is a schematic diagram of the overall structure of Embodiment 2 of the present invention;

[0036] Fig.11 The cross-sectional view of the flow diversion cavity and the surge cavity of the second and third embodiments of the present invention is shown in FIG.

[0037] Figures 12a to 12c They are respectively a bottom view, a front view and a cross-sectional view of the third embodiment of the water jet diversion structure in the present invention;

[0038] Fig.13 It is a schematic diagram of the overall structure of the third embodiment of the water jet diversion structure in the present invention;

[0039] Reference numerals:

[0040] 1. flow dividing cavity; 11. first end surface; 12. second end surface; 13. bottom surface; 14. peripheral surface;

[0041] 2. Surge chamber; 21. Fully open working surface; 22. Semi-open working surface; 23. Long strip notch; 24. Small hole; 25. Surge wall;

[0042] 3. Inlet pipe; 4. Diversion hole; 5. Connecting parts. DETAILED DESCRIPTION

[0043] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific diagrams.

[0044] See also Figure 2a to Figure 2c , which is a schematic diagram of the water jet diversion structure provided by the present invention.

[0045] As can be seen from the figure, the water jet diversion structure mainly includes a diversion cavity 1 and a surge cavity 2.

[0046] The diverter cavity 1 is defined by a first end face 11, a second end face 12, a bottom face 13 and a peripheral face 14 to form a closed chamber. The first end face 11 of the diverter cavity 1 is connected to the inlet pipe 3, the second end face 12 is closed, and a plurality of diverter holes 4 are provided on the bottom face 13. The surge cavity 2 is arranged below the diverter cavity 1 and is connected to the diverter cavity 1 through the diverter holes 4, so that the inlet pipe 3 introduces the working liquid into the diverter cavity 1, and the working liquid evenly enters the surge cavity 2 through the diverter holes 4, and finally is released to the circuit board through the surge cavity 2 to process the circuit board.

[0047] In order to specifically illustrate the composition of the water jet diversion structure, an example is given below.

[0048] Embodiment 1:

[0049] See also Figures 3 to 7 , which shows the first embodiment of the water jet diversion structure provided by the present invention.

[0050] According to Bernoulli's principle, It refers to the pressure potential energy p and kinetic energy per unit volume of fluid at any cross section of the same flow tube. The sum of the potential energy ρgh is a constant.

[0051] Among them, p is the pressure of the fluid, ρ is the density of the fluid, v is the flow velocity of the fluid, g is the acceleration due to gravity, h is the height of the fluid, and C is a constant.

[0052] Since the water jet diversion structure is installed horizontally in the circuit board equipment, the height h of the fluid at each location in the diversion cavity 1 can be considered equal. At the same time, the fluid density ρ and the gravitational acceleration g are known and determined. Therefore, the pressure p and flow velocity v of the fluid at different positions in the diversion cavity 1 are proportional.

[0053] by Figure 8 As shown in the figure, the fluids at points A and B in the flow-dividing chamber 1 are taken as an example. According to the Bernoulli principle,

[0054] Where p1 is the pressure of the fluid at point A, v1 is the flow rate of the fluid at point A, h1 is the height of the fluid at point A, p2 is the pressure of the fluid at point B, v2 is the flow rate of the fluid at point B, h2 is the height of the fluid at point B, ρ is the fluid density, and g is the acceleration due to gravity;

[0055] Since the water jet flow splitter structure is installed horizontally in the circuit board equipment, the heights of the fluids at points A and B are equal, that is, h1 = h2. Therefore,

[0056] It can be concluded that the pressure p1 and flow velocity v1 of the fluid at point A are proportional to the pressure p2 and flow velocity v2 of the fluid at point B. Therefore, when the flow velocity v1 of the fluid at point A is the same as the flow velocity v2 of the fluid at point B, the pressure p1 of the fluid at point A is the same as the pressure p2 of the fluid at point B.

[0057] From this we can conclude that in the same fluid system, if the flow velocities v at equal heights are equal, then the pressures p are equal.

[0058] Furthermore, according to the relationship between flow velocity v and flow rate Q, it can be expressed as Among them, Q is the flow rate of the fluid, S is the flow cross-section of the fluid. It can be seen that when the flow cross-section S of the fluid and the flow rate Q change in geometric proportion, the flow velocity v can remain unchanged, that is, the pressure p of the fluid remains unchanged, so that the pressure p of the fluid at various locations in the diversion cavity 1 is consistent, so that each diversion hole 4 can evenly pass an equal amount of fluid.

[0059] Combination Figures 3 to 7In order to make the flow cross-section S and flow rate Q of the fluid at each location in the diverter cavity 1 change in equal proportion to ensure that the flow velocity v and the pressure p of the fluid remain unchanged, the cross-section of the diverter cavity 1 defined by the peripheral surface 14 and the bottom surface 13 is configured to decrease in equal proportion from the first end surface 11 to the second end surface 12 along the length L direction of the diverter cavity 1, so that the flow cross-section S of the fluid in the diverter cavity 1 is reduced in equal proportion.

[0060] At the same time, combined Figure 5 and Figure 8 The diversion holes 4 are evenly distributed along the length direction of the diversion cavity 1, and the fluid flow rate Q is proportional to the distance L' from the fluid position to the second end face 12, so that the fluid flow rate Q in the diversion cavity 1 decreases proportionally from the first end face 11 to the second end face 12 in the length L direction.

[0061] Furthermore, the flow cross-sectional area S of the fluid in the diverter cavity 1 is equal to the cumulative cross-sectional area of ​​the diverter holes 4, that is, the cross-sectional area S1 of the first end face 11 of the diverter cavity 1 is equal to the cumulative cross-sectional area S3 of all the diverter holes 4, expressed as S1=S3, so that the cross-sectional change of the diverter cavity 1 corresponds to the arrangement of the diverter holes 4, so that the flow cross-sectional area S and flow rate Q of the fluid at various locations in the diverter cavity 1 change in equal proportion, so that the flow velocity v remains unchanged, that is, the pressure p of the fluid remains unchanged, and then the pressure p of the fluid at various locations in the diverter cavity 1 is consistent, and each diverter hole 4 can evenly pass an equal amount of fluid, ensuring uniform diversion and improving the overall uniformity of circuit board processing.

[0062] In order to illustrate the specific structure of the flow-dividing chamber 1 , the inclined angle θ of the flow-dividing chamber 1 is illustrated below.

[0063] Specifically, S1 = S3, where S1 = w × H1, S3 = (π × R 2 )×n, H1 is the cross-sectional height of the first end surface 11, w is the width of the diverter cavity 1, R is the radius of the diverter hole 4, n is the total number of the diverter holes 4,

[0064] From this, we can get w×H1=(π×R 2 )×n, that is, H1=(π×R 2 )×n / w, since the inclination angle θ of the diversion cavity 1 is Thus, the tilt angle of the diverter cavity 1 can be

[0065]

[0066] Therefore, the inclination angle θ of the diverter cavity 1 can be determined by knowing the length L of the diverter cavity 1, the width w of the diverter cavity 1, the radius R of the diverter hole 4 and the total number n of the diverter holes 4, so as to configure the specific structure of the diverter cavity 1. Here, the inclination angle θ of the diverter cavity 1 is preferably between 3° and 30°, so that the flow cross-section S and flow rate Q of the fluid at various locations in the diverter cavity 1 can be easily configured to change in proportion, so as to keep the pressure p of the fluid consistent.

[0067] Furthermore, the fluids at various locations in the flow-dividing chamber 1 flow into the flow-surging chamber 2 evenly and equally through each flow-dividing hole 4, so that the flow-surging chamber 2 releases the fluids onto the circuit board through the working surface of the bottom surface.

[0068] Specifically, surge walls 25 are provided on both sides of the surge chamber 2, and a working surface is provided between the bottoms of the surge walls 25 on both sides, so that when the fluid flows into the surge chamber 2 from the diversion hole 4, the surge wall 25 can limit the flow range of the fluid, and at the same time, the flow of the fluid in the surge chamber 2 will not be affected by the outside world, so that the fluid can be evenly released from the surge chamber 2 through the working surface onto the circuit board.

[0069] Combination Figure 6 and Figure 7 In the first embodiment, the working surface of the flow chamber 2 is configured as a fully open working surface 21, so that the fluid in the diversion chamber 1 enters the flow chamber 2 through the diversion hole 4 and is directly released onto the circuit board through the fully open working surface 21, thereby making the fluid flow rate at various locations on the circuit board equal.

[0070] Furthermore, since the bottom surface of the flow chamber 2 is a fully open working surface 21, the fluid is directly released from the diversion hole 4 to the circuit board gently and evenly. For fluids that are prone to crystallization, the transportation path of the fluid is reduced, thereby effectively reducing the risk of crystallization of the fluid during transportation, thereby improving the utilization rate of the fluid and the processing effect on the circuit board.

[0071] Embodiment 2:

[0072] See also Figures 9a to 9c , which shows the second embodiment of the water jet diversion structure of the circuit board device provided by the present invention.

[0073] On the basis of Example 1, when the water jet diversion structure is used for circuit board equipment in a high-flow and low-pressure system, in order to increase the flow rate of the fluid released to the circuit board and achieve uniform spraying of the fluid on the circuit board, so that the fluid flow on the circuit board is larger and the circuit board is effectively flushed and processed, the flow rate and pressure released to the circuit board need to be controlled.

[0074] Therefore, combined with Fig.10 and Fig.11In the second embodiment, based on the first embodiment, the working surface of the flow chamber 2 is configured as a semi-open working surface 22, and a plurality of long strip-shaped notches 23 are evenly distributed on the semi-open working surface 22.

[0075] Furthermore, the total cross-sectional area of ​​all the long strip slots 23 on the semi-open working surface 22 is ≥ the cumulative cross-sectional area S3 of all the diversion holes 4 in the diversion cavity 1, so that the fluid in the diversion cavity 1 enters the surge cavity 2 through the diversion holes 4, and is then released to the circuit board through the long strip slots 23 on the semi-open working surface 22 at the bottom of the surge cavity 2. Since the cross-sectional area of ​​the long strip slots 23 is larger, the long strip slots 23 can make the fluid experience a longer path in the process of passing through the long strip slots 23, so as to increase the friction between the fluid and the slot wall in the long strip slots 23, thereby reducing the speed of the fluid, reducing the kinetic energy, and causing a pressure drop.

[0076] At the same time, the long strip slots 23 can also cause the fluid to generate more vortices and turbulence when passing through the slots. These vortices and turbulence will further consume the kinetic energy of the fluid, resulting in a decrease in pressure, thereby increasing the flow released to the circuit board through the long strip slots 23.

[0077] Here, the number and size of the long strip slots 23 are not limited, and can be adaptively adjusted according to the fluid type and the required flow rate. Preferably, in the second embodiment, two rows of evenly staggered long strip slots 23 are provided on the semi-open working surface 22 to increase the contact area between the fluid and the long strip slots 23, reduce the pressure, and increase the flow rate through the long strip slots 23, so that the fluid is released from the long strip slots 23 onto the circuit board at a larger flow rate, achieving a spraying effect on the circuit board, and effectively treating the circuit board evenly.

[0078] Embodiment three:

[0079] See also Figures 12a to 12c , which shows the third embodiment of the water jet diversion structure of the circuit board device provided by the present invention.

[0080] On the basis of Example 1, when the water jet diversion structure is used for circuit board equipment in a high-pressure and low-flow system and the circuit board needs to be filled with holes, in order to allow the fluid to have a greater impact force to fill the holes in the circuit board and to prevent the fluid pressure on the circuit board from being too low, resulting in the fluid not being able to fully exert its effect on the precise processing of the circuit board, causing the surface structure of the circuit board to be untidy, it is necessary to control the flow and pressure released to the circuit board.

[0081] Therefore, combined with Fig.11 and Fig.13 In the third embodiment, based on the first embodiment, the working surface of the flow chamber 2 is configured as a semi-open working surface 22, and a plurality of small holes 24 are evenly distributed on the semi-open working surface 22.

[0082] Furthermore, the total cross-sectional area of ​​all the small holes 24 on the semi-open working surface 22 is ≤ the cumulative cross-sectional area S3 of all the diverter holes 4 in the diverter cavity 1, so that the fluid in the diverter cavity 1 enters the surge cavity 2 through the diverter holes 4, and is then released to the circuit board through the small holes 24 on the semi-open working surface 22 at the bottom of the surge cavity 2. Since the cross-sectional area of ​​the small holes 24 is small, the fluid needs to be accelerated to pass through the small holes 24, so the flow rate increases. According to the Bernoulli equation, the pressure of the fluid will decrease, but after passing through the small holes 24, during the process of the fluid being released to the circuit board, the fluid enters a larger space relative to the small holes 24. In this space, the flow rate of the fluid will decrease. According to the Bernoulli equation, the fluid pressure will increase, so that the fluid is released from the small holes 24 to the circuit board at a higher pressure, and the circuit board can be filled with holes.

[0083] Here, the number and size of the small holes 24 are not limited and can be adaptively adjusted according to the fluid type and the required flow rate. Preferably, in Example 3, the radius of the small hole is preferably 0.5-1 mm, and two rows of small holes 24 evenly arranged in parallel are provided on the semi-open working surface 22 to reduce the flow rate of the fluid after passing through the small holes 24 and increase the fluid pressure.

[0084] On the basis of Example 1, Example 2 and Example 3, in order to facilitate the installation and removal of the water jet diversion structure from the circuit board device, connecting parts 5 are respectively provided at both ends of the flow chamber 2, so that the water jet diversion structure can be connected to the circuit board device through the connecting parts 5. Preferably, the connecting parts 5 are composed of pins, so that the water jet diversion structure can be easily and quickly assembled and disassembled.

[0085] Furthermore, the water jet diversion structure can be composed of titanium or stainless steel panels according to the fluid characteristics, and can also be composed of engineering plastic panels such as PVC or PP, so that the water jet diversion structure meets the requirements of corrosion resistance and high temperature resistance.

[0086] Furthermore, the water jet diversion structure can be installed in multiple directions. In Example 1, Example 2 and Example 3, the diversion chamber 1 and the surge chamber 2 are installed horizontally downward. As an example, the diversion chamber 1 and the surge chamber 2 can also be configured to be installed horizontally upward, to the left or to the right, so that the water jet diversion structure can adapt to different circuit board equipment.

[0087] Among them, the device body and the circuit board are prior art and should be well known to those skilled in the art, and will not be described in detail here.

[0088] The water jet diversion structure and circuit board equipment provided by the present invention adopt a diversion cavity 1 that is proportionally reduced, and at the same time, the diversion holes 4 are evenly distributed, so that when the flow cross-section S and flow rate Q of the fluid in the diversion cavity 1 change in a proportional manner, the flow velocity v can remain unchanged, that is, the pressure p of the fluid remains unchanged, so that the pressure p of the fluid at various locations in the diversion cavity 1 is consistent, so that each diversion hole 4 can evenly pass an equal amount of fluid; at the same time, the working surface of the flow cavity 2 is configured as a fully open working surface 21 and a semi-open working surface 22 according to the fluid type and equipment characteristics, so as to achieve the effect of pressurizing or depressurizing the fluid.

[0089] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A water jet diversion structure, characterized in that: It includes A flow dividing cavity, wherein the flow dividing cavity is defined by a bottom surface, a peripheral surface, a first end surface and a second end surface to form a closed cavity; A plurality of diversion holes arranged on the bottom surface; an inlet pipe disposed on the first end surface, the inlet pipe introducing the working fluid into the diversion cavity, and A surge cavity is arranged below the diversion cavity, and the surge cavity is connected with the diversion cavity through the plurality of diversion holes. Among them, the cross-section of the diverter cavity defined by the peripheral surface and the bottom surface decreases proportionally from the first end surface to the second end surface along the length direction of the diverter cavity, the diverter holes are evenly distributed equidistantly along the length direction of the diverter cavity, and the cross-sectional area S1 of the first end surface of the diverter cavity is equal to the cumulative cross-sectional area S3 of all the diverter holes.

2. The water jet flow diversion structure according to claim 1, characterized in that: The inclination angle θ of the diversion cavity is Wherein, L is the length of the diverter cavity, w is the width of the diverter cavity, R is the radius of the diverter hole, and n is the total number of the diverter holes.

3. The water jet flow diversion structure according to claim 1, characterized in that: Both sides of the flow chamber are provided with flow walls for limiting the flow range of the working liquid.

4. The water jet flow diversion structure according to claim 1, characterized in that: The bottom surface of the surge chamber and the circuit board cooperates to form a fully open working surface or a semi-open working surface.

5. The water jet flow diversion structure according to claim 4, characterized in that: A plurality of long strip-shaped notches are evenly distributed on the semi-open working surface of the flow cavity.

6. The water jet flow diversion structure according to claim 5, characterized in that: The total cross-sectional area of ​​all the long strip-shaped slots is ≧ the cumulative cross-sectional area S3 of all the diversion holes.

7. The water jet flow diversion structure according to claim 4, characterized in that: A plurality of small holes are evenly distributed on the semi-open working surface of the flow chamber.

8. The water jet flow diversion structure according to claim 7, characterized in that: The total cross-sectional area of ​​all the holes ≦ The cumulative cross-sectional area of ​​all the diversion holes is S3.

9. The water jet flow diversion structure according to claim 1, characterized in that: Connectors for detachably connecting with circuit board equipment are respectively provided at both ends of the surge chamber.

10. The water jet flow diversion structure according to claim 9, characterized in that: The connecting piece is composed of a latch.

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