Chemical diaphragm pump for diffusion of crystalline silicon solar cell

Abstract

The utility model relates to the technical field of diaphragm pumps, in particular to a chemical diaphragm pump for diffusion of crystalline silicon solar cells, which comprises a motor, a pump casing, an eccentric shaft connecting rod component, a diaphragm cavity, a gas circuit assembly and a pipeline. The pump shell comprises two end covers and four side walls, a connecting wall is arranged between every two adjacent side walls, heat dissipation holes penetrating through the connecting walls in the length direction of the connecting walls are formed in the connecting walls, and the heat dissipation holes communicate with the space outside the end covers. The thickness of the connecting wall is greater than that of the side wall; the end part of a connecting rod of the eccentric shaft connecting rod assembly corresponds to one film cavity, and each film cavity is communicated with the gas circuit assembly through a pipeline; a fillet transition with the radius larger than or equal to 20 mm is arranged at the turning position of the pipeline. The chemical diaphragm pump is applied to photovoltaic equipment to solve the problems of short diaphragm service life, high maintenance cost, long maintenance period and the like of the conventional chemical diaphragm pump.

Description

Technical Field

[0001] The utility model relates to the technical field of diaphragm pumps, and particularly relates to a chemical diaphragm pump for diffusion of crystalline silicon solar cells. Background Art

[0002] In the production of solar cells, in the low-pressure phosphorus diffusion process, under the action of a vacuum pump, the reaction chamber is in a vacuum state, and then process gases are introduced. During the diffusion process, the chamber is maintained at a constant vacuum state to ensure that the concentration of phosphorus ions in the chamber remains unchanged.

[0003] Currently, the chemical diaphragm pumps widely used in the industry generally have problems such as pump body corrosion, short diaphragm life, high maintenance cost, and long maintenance cycle. Based on the research of the problems of current similar equipment, a series of optimizations and improvements are needed to improve the service life of the diaphragm pump and reduce the maintenance and operation costs. Summary of the Utility Model

[0004] To solve the above technical problems, the utility model provides a chemical diaphragm pump for diffusion of crystalline silicon solar cells, which solves the problems of short diaphragm life, high maintenance cost, and long maintenance cycle of existing chemical diaphragm pumps.

[0005] The technical solution of the utility model is as follows:

[0006] A chemical diaphragm pump for diffusion of crystalline silicon solar cells, the diaphragm pump includes a motor, a pump housing, an eccentric shaft connecting rod assembly, a diaphragm chamber, an air circuit assembly and a pipeline;

[0007] The pump housing includes two end covers and four side walls. A connecting wall is provided between every two adjacent side walls. Heat dissipation holes penetrating the connecting wall along the length direction of the connecting wall are provided on the connecting wall, and the heat dissipation holes communicate with the space outside the end cover; and the thickness of the connecting wall is greater than the thickness of the side wall;

[0008] The connecting rod ends of the eccentric shaft connecting rod assembly respectively correspond to one of the diaphragm chambers, and each diaphragm chamber is communicated with the air circuit assembly through a pipeline; a fillet transition with a radius ≥ 20 mm is provided at the turning point of the pipeline.

[0009] By providing a fillet transition for the pipeline, the heat deformation of the pipeline is reduced, thereby reducing and avoiding the problem of poor air flow. Heat dissipation holes are provided on the pump housing to strengthen heat dissipation, thereby reducing the problems of pump body corrosion and short diaphragm life of the diaphragm pump.

[0010] Further, the cross-section of the heat dissipation hole is an isosceles trapezoid, the long side length of the isosceles trapezoid is 30 mm, the short side length is 15 mm, the waist length is 14 mm, and the short side of the isosceles trapezoid faces the central axis of the pump housing.

[0011] The heat dissipation holes are arranged as isosceles trapezoids. On the one hand, it is to fit the shape of the pump housing. On the other hand, it is to avoid the connecting bolts for fastening the top cover. The inner ends of the heat dissipation holes are inwardly retracted, so that the bolt holes for fixing the top cover will not communicate with the inside of the pump housing.

[0012] Further, the end cover of the pump housing is an end cover that closes the inner cavity of the pump housing. The end cover is provided with through holes corresponding to the heat dissipation holes on the connecting wall, and the shape of the through holes is the same as that of the heat dissipation holes.

[0013] The end cover is set as a square, which can strengthen the connection. The through holes are arranged on the end cover and communicate with the heat dissipation holes to form a heat dissipation channel, enhancing heat dissipation.

[0014] Further, the inner cavity of the pump housing is a cylindrical chamber. The inner cavity of the pump housing is provided with grooves along the length direction of the pump housing, and the grooves are close to the heat dissipation holes.

[0015] The grooves are for reducing the space partition inside the pump housing. When the eccentric shaft connecting rod assembly operates, a circulation channel is formed inside the pump housing to strengthen the internal air circulation, and also increase the inner wall area of the pump housing.

[0016] Further, the length of the pump housing is 325 mm. Each side wall of the pump housing is provided with three diaphragm cavities, and the diaphragm cavities on adjacent side walls are arranged in a staggered manner, and the diaphragm cavities on the mutually parallel side walls are coaxially opposite.

[0017] The pump housing of the present utility model is longer than the pump housing in the prior art, has a larger internal space, and better heat dissipation, compared with the prior art.

[0018] Further, the side wall of the pump housing is provided with connection holes. The connecting rod end of the eccentric shaft connecting rod assembly is connected to the diaphragm. The diaphragm is pressed by the top cover at the connection holes on the side wall of the pump housing, and the cavity between the diaphragm and the top cover forms a diaphragm cavity.

[0019] Further, the side wall of the pump housing and the connecting wall are integrally cast.

[0020] Further, the center distance of the diaphragm cavities on the same side wall is 96.50 ± 0.05 mm.

[0021] Further, the pipe is a pipe made of PFA resin, and the outer diameter of the pipe is 10 mm and the wall thickness is 1.8 mm.

[0022] The pipe made of PFA resin has higher high-temperature resistance, is not easily deformed, has a thicker pipe wall, has strong mechanical strength and burst pressure, can prevent problems such as the increase in pump speed and the sharp rise in pump body temperature caused by pipe deformation and blockage, and thus will not occur the situations of diaphragm bulging, short service life and internal corrosion of the pump body caused by acid leakage.

[0023] Beneficial effects

[0024] 1. The pipeline of the present utility model has a relatively large turning radius, which can prevent deformation caused by heat shock. At the same time, the housing has heat dissipation holes, reducing the heat accumulation inside the pump housing, thereby reducing the pump body corrosion of the diaphragm pump and the problem of short diaphragm life. The present utility model is applied to photovoltaic equipment, reducing the comprehensive operation and maintenance cost by about 50%.

[0025] 2. The present utility model increases the length of the pump housing and the number of diaphragm chambers. After adjusting the distribution of the diaphragm chambers, the performance of the reciprocating pump and the pump is effectively improved. The operating temperature on the pump body surface is basically maintained between 40 - 50 °C. And when the power of the driving motor remains unchanged at 1000 w, the overall performance is improved by about 30%. The maximum pumping speed is increased from 15.2 m

[0026] / h to 20.5 m3 / h, and the regulated pressure accuracy is controlled within 0.1 mbar. Description of the Drawings

[0027] Figure 1 is a schematic structural view of the present utility model;

[0028] Figure 2 is a schematic structural view of the pump housing of the present utility model;

[0029] Figure 3 is a schematic structural view of the end cover of the present utility model.

[0030] The reference numerals in the drawings are: 1, motor; 2, pump housing; 3, gas circuit assembly; 4, pipeline; 5, clamp; 6, end cover; 7, side wall; 8, connecting wall; 9, heat dissipation hole; 10, top cover; 11, through hole; 12, groove; 13, connecting hole. Detailed Embodiment

[0031] In order to make the purpose, technical solutions and advantages of the present utility model clearer, the following further details the present utility model in conjunction with specific embodiments.

[0032] As Figure 1 and Figure 2 shown, a chemical diaphragm pump for diffusion of crystalline silicon solar cells includes a pump body. The pump body includes a motor 1, a pump housing 2, an eccentric shaft connecting rod assembly, a diaphragm chamber and a gas circuit assembly 3. The output shaft of the motor 1 penetrates through the pump housing 2 and is connected to the eccentric shaft connecting rod assembly located inside the pump housing 2. The connecting rod ends of the eccentric shaft connecting rod assembly respectively correspond to a diaphragm chamber. Each diaphragm chamber is communicated with the gas circuit assembly 3 through a pipeline 4. A fillet transition with a radius ≥ 20 mm is provided at the turning of the pipeline 4. The pipeline 4 is connected using a clamp 5 for easy replacement;

[0033] The pump housing 2 has two end covers 6 and four side walls 7. Among the four side walls 7, two adjacent side walls 7 are perpendicular to each other, and the two spaced side walls 7 are parallel to each other. Wherein, a connecting wall 8 is provided between every two adjacent side walls 7. The thickness of the connecting wall 8 is greater than that of the side wall 7, and the width of the connecting wall 8 is less than that of the side wall 7. A heat dissipation hole 9 penetrating the connecting wall 8 along the length direction of the connecting wall 8 is provided on the connecting wall 8, and the heat dissipation hole 9 communicates with the space outside the end cover 6.

[0034] On the surface, the problems of pump body corrosion and short diaphragm life are that the diaphragm is not resistant to high temperature and corrosion. However, from the actual production and maintenance of the diaphragm pump, it is found that: it mainly focuses on two aspects. One is that the existing pump housing 2 is relatively short, and the membrane cavities are distributed densely, resulting in heat accumulation and poor heat dissipation effect; the other is that the pipe 4 connecting the membrane cavities is softened by heat during the heat accumulation process due to the material, and in addition, the wall thickness is small, the turning at the transition is relatively urgent, and it is greatly impacted by the air flow. After deformation, the cross-sectional area of the internal passage of the pipe 4 decreases, resulting in unsmooth air flow. In order to maintain a constant pressure balance, the pump body increases the rotational speed, and then due to the poor heat dissipation of the pump housing 2, the temperature rises, affecting the performance of the diaphragm. The diaphragm delaminates after the use temperature is higher than the rated temperature, and then pump body corrosion is formed.

[0035] The present utility model starts from these two aspects, sets a fillet transition with a radius ≥ 20 mm for the pipe 4, increases the transition fillet, reduces the impact of the air flow on the pipe wall, reduces the heat deformation of the pipe 4, thereby avoiding the problem of unsmooth air flow, and sets heat dissipation holes on the pump housing 2 to strengthen heat dissipation, thereby reducing the problems of pump body corrosion and short diaphragm life of the diaphragm pump.

[0036] The cross-section of the heat dissipation hole 9 is an isosceles trapezoid. The long side length of the isosceles trapezoid is 30 mm, the short side length is 15 mm, the waist length is 14 mm, and the short side of the isosceles trapezoid faces the central axis of the pump housing 2.

[0037] The heat dissipation hole 9 is set as an isosceles trapezoid. On the one hand, it matches the shape of the pump housing 2, and on the other hand, it is to avoid the connecting bolts for fastening the top cover 10 and prevent the bolt holes from communicating with the inner cavity of the pump housing 2.

[0038] As Figure 3 shown, the end cover 6 of the pump housing 2 is an end cover that closes the inner cavity of the pump housing 2. A through hole 11 corresponding to the heat dissipation hole 9 on the connecting wall 8 is provided on the end cover 6, and the shape of the through hole 11 is the same as that of the heat dissipation hole 9.

[0039] The shape of the end cover 6 is the same as the cross-sectional contour of the pump housing 2. The edge of the end cover 6 is used to strengthen the connection with the side wall 7 and the connecting wall 8. A through hole 11 is provided on the end cover 6, which communicates with the heat dissipation hole 9 to form a heat dissipation channel and strengthen heat dissipation.

[0040] The inner cavity of the pump housing 2 is a cylindrical chamber, and a groove 12 along the length direction of the pump housing 2 is provided on the inner cavity of the pump housing 2, and the groove 12 is close to the heat dissipation hole 9.

[0041] The purpose of the groove 12 is to reduce the space division inside the pump housing 2 , so that a circulation channel is formed in the pump housing 2 when the eccentric shaft connecting rod assembly is running, thereby enhancing the internal air circulation and increasing the area of the inner wall of the pump housing 2 .

[0042] The length of the pump housing 2 is 325 mm. Three membrane cavities are provided on each side wall 7 of the pump housing 2. The membrane cavities on adjacent side walls 7 are staggered, and the membrane cavities on the side walls 7 that are parallel to each other are coaxially opposite to each other.

[0043] The pump housing 2 of the utility model is longer than the pump housing in the prior art, has a larger internal space, and has better heat dissipation.

[0044] A connecting hole 13 is provided on the side wall 7 of the pump housing 2. The connecting rod end of the eccentric shaft connecting rod assembly is connected to the diaphragm. The diaphragm is pressed onto the connecting hole 13 on the side wall 7 of the pump housing 2 through the top cover 10. The cavity between the diaphragm and the top cover constitutes a diaphragm cavity.

[0045] The side wall 7 and the connecting wall 8 of the pump housing 2 are integrally cast.

[0046] The center distance of the membrane cavities on the same side wall 7 is 96.50±0.05 mm.

[0047] The pipe 4 is a pipe made of PFA resin, and the outer diameter of the pipe 4 is 10 mm and the wall thickness is 1.8 mm.

[0048] The utility model utilizes the pipe made of PFA resin with higher high temperature resistance, is not easy to deform, has thickened pipe wall, has strong mechanical strength and bursting pressure, and can prevent the problem of rapid heating of the pump body when the pump speed is turned on due to pipeline deformation and blockage, thereby solving the problems of diaphragm bulging, short service life and internal corrosion of the pump body caused by acid leakage.

[0049] Compared with the hexagonal ten-cylinder diaphragm pump in the prior art, the utility model has a larger pump body length, symmetrically arranged pump heads, a more reasonable structure, and the number of pump heads is increased from 10 to 12. The operating temperature of the pump body surface is basically maintained between 40-50°C, and the overall performance is improved by about 30% when the driving motor power remains unchanged at 1000w. The maximum pumping speed is increased from 15.2m3 / h to 20.5m3 / h, and the voltage stabilization accuracy is controlled at 0.1mbar. When used for low-pressure phosphorus diffusion, the pressure in the low-pressure phosphorus diffusion cavity is pumped from normal pressure to 500mbar for voltage stabilization within 30s-40s, and then can be pumped to 80mbar within 50s for the process. After long-term tracking verification, there is no offline maintenance record for 8 months of operation. The application of the utility model in photovoltaic equipment reduces the comprehensive operation and maintenance costs by about 50%.

[0050] It should be understood that the specific embodiments described herein are merely used to explain the present utility model and are not intended to limit the present utility model.

Claims

1. A chemical diaphragm pump for diffusion of crystalline silicon solar cells, characterized in that, The diaphragm pump includes a motor (1), a pump housing (2), an eccentric shaft connecting rod assembly, a diaphragm cavity, an air circuit assembly (3) and a pipeline (4). The pump housing (2) includes two end covers (6) and four side walls (7). A connecting wall (8) is provided between every two adjacent side walls (7). Heat dissipation holes (9) penetrating the connecting wall (8) along the length direction of the connecting wall (8) are provided on the connecting wall (8), and the heat dissipation holes (9) communicate with the space outside the end cover (6); and the thickness of the connecting wall (8) is greater than the thickness of the side wall (7). The eccentric shaft connecting rod assembly, the connecting rod ends of which respectively correspond to one of the diaphragm cavities, and each diaphragm cavity communicates with the air circuit assembly (3) through a pipeline (4); a fillet transition with a radius ≥ 20 mm is provided at the turning point of the pipeline (4).

2. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, characterized in that, The cross-section of the heat dissipation hole (9) is an isosceles trapezoid, the long side of the isosceles trapezoid is 30 mm, the short side is 15 mm, the waist length is 14 mm, and the short side of the isosceles trapezoid faces the central axis of the pump housing (2).

3. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, wherein, The end cover (6) of the pump housing (2) is an end cover (6) that closes the inner cavity of the pump housing (2). Through holes (11) corresponding to the heat dissipation holes (9) on the connecting wall (8) are provided on the end cover (6), and the shapes of the through holes (11) are the same as the shapes of the heat dissipation holes (9).

4. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, wherein The inner cavity of the pump housing (2) is a cylindrical chamber, and a groove (12) along the length direction of the pump housing (2) is provided on the inner cavity of the pump housing (2), and the groove (12) is close to the heat dissipation hole (9).

5. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, characterized in that, The length of the pump housing (2) is 325 mm. Three diaphragm cavities are provided on each side wall (7) of the pump housing (2). The diaphragm cavities on adjacent side walls (7) are arranged in a staggered manner, and the diaphragm cavities on the mutually parallel side walls (7) are coaxially opposite to each other.

6. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, wherein Connecting holes (13) are provided on the side wall (7) of the pump housing (2). The connecting rod end of the eccentric shaft connecting rod assembly is connected to a diaphragm, and the diaphragm is pressed at the connecting hole (13) on the side wall (7) of the pump housing (2) through a top cover (10). The cavity between the diaphragm and the top cover forms a diaphragm cavity.

7. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, characterized in that, The side wall (7) of the pump housing (2) and the connecting wall (8) are integrally cast.

8. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, characterized in that, The center distance of the diaphragm cavities on the same side wall (7) is 96.50 ± 0.05 mm.

9. The chemical diaphragm pump for diffusion of crystalline silicon solar cells according to claim 1, characterized in that, The pipeline (4) is a pipe made of PFA resin, and the outer diameter of the pipeline (4) is 10 mm and the wall thickness is 1.8 mm.

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