Position adjusting system for printing head on rotating disc type photovoltaic screen printing machine

Abstract

The invention discloses a position adjusting system for a printing head on a rotating disc type photovoltaic screen printing machine. The position adjusting system comprises a base plate, three movable supporting seats, a fixed supporting seat, two screen printing plate supporting air cylinders, a screen printing plate movable bottom plate and a screen printing plate mounting frame. The top face of the base plate is provided with two rectangular channels of X-direction channels and two rectangular channels of Y-direction channels. The three movable supporting seats are installed in the middle of one X-direction channel and in the middle of the two Y-direction channels of the base plate. The fixed supporting seat is mounted in the middle of the other X-direction channel; the two screen supporting air cylinders are installed in the two X-direction channels. The screen printing plate moving bottom plate is mounted on inner rings of the crossed roller bearings at the tops of the three moving supporting seats and inner rings of the crossed roller bearings at the top of the fixed supporting seat; the screen installation frame is installed on the top face of the screen moving bottom plate and connected with the two conical heads penetrating out of the two guide holes in the screen moving bottom plate in a clamped mode through the two caulking grooves. According to the invention, the printing registration precision of the printing head and the silicon crystal battery piece can be further improved.

Description

Technical Field

[0001] The invention relates to a position adjustment system for a printing head on a rotary disc type photovoltaic screen printer. Background Art

[0002] Screen printing (printing conductive silver paste on silicon wafers) is the most important step in the preparation of solar panels, which directly determines the power generation efficiency of solar panels. With the development of science and technology, the power generation of solar panels has been continuously improved, and the requirements for the preparation equipment of solar panels, especially the screen printing part, have become higher and higher. The existing product printing line width is basically around 25μm, and the printing registration requirements for lines are generally ±5~10μm. Now with the continuous advancement of industry technology and cost-based requirements, the printed product lines are getting thinner and thinner, and the new technology line width is less than 20μm, which requires higher registration accuracy to meet the production and promotion of new technologies.

[0003] The photovoltaic cell screen printing equipment currently on the market has structures such as linear interactive and track-type. The accuracy, speed and stability of these types of screen printing equipment sometimes cannot meet the printing requirements of photovoltaic cell silicon crystals. There is also a turntable photovoltaic screen printing machine, which adopts a five-station working turntable conveying form, cooperates with a detection device and two adjustable screen printing heads. It has made breakthroughs in accuracy and stability, and can effectively improve the screen printing quality of silicon crystal cell wafers and improve production efficiency. This turntable photovoltaic screen printing machine includes a base 1, a working turntable 2, a feed conveying device 8, a loading conveying device 3, a visual inspection device 4, a first screen printing head 5, a second screen printing head 6, a unloading conveying device 7 and a discharging conveying device 9 (see Chinese patent CN202322694766.1 and see Figure 1 ). The first screen printing head 5 is used to screen print silver paste on a silicon crystal cell 10, and it can be adjusted in the X direction, Y direction, Z direction and T (angle). Before printing, according to the position deviation data of the silicon crystal cell 10 obtained by the visual inspection device 4, it is quickly adjusted to be flush with the position of a silicon crystal cell 10 on the printing table 20 before printing. The structure of the second screen printing head 6 is the same as that of the first screen printing head 5. The second screen printing head 6 is flush with the position of another silicon crystal cell 10 on the printing table 20 before printing.

[0004] The position adjustment system of the printing head on the existing rotary screen printing machine has the following two defects:

[0005] 1. In the existing rotary screen printing machine, the drive mechanisms involved in the X-axis, Y-axis and T (angle) adjustment mechanisms of the print head position adjustment system are installed at different levels, that is, there are three coordinate systems for action execution (see Figure 2), while the data processed by the detection device (visual processing system) is read and processed on the same plane. Taking into account the errors in the installation of each actuator, the actual results produced by the movement of the X-, Y- and T-axis actuators according to the data provided by the detection device deviate from the data provided by the detection device.

[0006] 2. When the existing screen printing equipment adjusts the T angle of the printing head, the independent servo motor drives the screen frame to rotate. This means that once the equipment is assembled, the rotation axis of the T coordinate system is fixed. The subsequent plate making requires that the center position of each graphic in the screen frame must perfectly coincide with the T rotation axis. In the actual plate making process, deviations are inevitable, and this deviation is not fixed. This part of the deviation cannot be calculated when the subsequent actuator processes the data. Existing equipment often ignores this data, and uniformly defaults to the center of the graphic of each screen coinciding with the T rotation axis during plate making. This will also cause deviations in the execution results in actual production; Summary of the invention

[0007] The purpose of the present invention is to overcome the defects of the prior art and provide a position adjustment system for a printing head on a photovoltaic screen printer, which further improves the printing registration accuracy between the printing head and the silicon crystal cell on the printing table and meets the printing registration requirements of finer lines.

[0008] The object of the present invention is achieved as follows: a position adjustment system for a printing head on a turntable photovoltaic screen printer, the turntable photovoltaic screen printer comprising a workbench, a work turntable, a visual inspection device and two screen printing heads; the position adjustment system for the printing head comprises a substrate, three movable support seats, a fixed support seat, two screen support cylinders, a screen movable bottom plate and a screen mounting frame; wherein,

[0009] The substrate is a rectangular plate with a rectangular through hole in the middle and an outer frame around it, and the substrate is installed on the top surface of the workbench through a Z-direction adjustment mechanism, an inner frame is provided on the top surface of the substrate along the four sides of the through hole, and a rectangular channel with two X-direction channels and two Y-direction channels is formed between the inner frame and the outer frame;

[0010] The three movable support seats are mounted one by one in the middle of one X-direction channel and the middle of two Y-direction channels of the base plate; each movable support seat comprises a mechanism bottom plate, a pair of lower cross roller guide rails mounted on the top surface of the mechanism bottom plate, a lower moving block mounted on the lower cross roller guide rails, a ball nut connected to the lower moving block, a ball screw mounted on the ball nut, a driving motor connected to the ball screw, a pair of upper cross roller guide rails mounted on the top surface of the lower moving block and perpendicular to the pair of lower cross roller guide rails, an upper moving block mounted on the upper cross roller guide rails, and a cross roller bearing mounted in the center of the top surface of the upper moving block;

[0011] The fixed support seat is installed in the middle of another X-direction channel of the base plate, and the fixed support seat includes a mechanism bottom plate, a pair of lower cross roller guide rails installed on the top surface of the mechanism bottom plate, a lower moving block installed on the lower cross roller guide rails, a pair of upper cross roller guide rails installed on the top surface of the lower moving block and perpendicular to the pair of lower cross roller guide rails, an upper moving block installed on the upper cross roller guide rails, and a cross roller bearing installed in the center of the top surface of the upper moving block;

[0012] Two screen supporting cylinders are installed in two X-direction channels one by one, and a conical head is installed at the center of the top surface of the piston rod of each screen supporting cylinder;

[0013] The screen moving bottom plate is a rectangular frame plate and is installed on the inner rings of the cross roller bearings on the tops of the three moving support seats and the inner rings of the cross roller bearings on the tops of the fixed support seats by screws; a guide hole coaxial with the piston rods of the two screen support cylinders is respectively provided on the two long sides of the screen moving bottom plate, so that the piston rods of the two screen support cylinders are inserted into the two guide holes one by one when they are extended at the same time;

[0014] A lower guide bar with an L-shaped cross-section is fixed to the bottom surface of each of the two long sides of the screen mounting frame, and a groove is provided on the horizontal portion of each of the two lower guide bars, which is matched with the conical heads on the two screen supporting cylinders. The screen mounting frame is installed on the top surface of the screen moving bottom plate and is clamped with the two conical heads that pass through the two guide holes on the screen moving bottom plate through the two grooves, which correspond one to one.

[0015] The position adjustment system of the printing head on the above-mentioned turntable photovoltaic screen printing machine, wherein an upper guide bar with an L-shaped cross-section and one-to-one connection with the two lower guide bars on the screen mounting frame is fixed on the top surface of each of the two long sides of the screen moving bottom plate.

[0016] In the above-mentioned position adjustment system for the printing head on the rotary disc photovoltaic screen printer, a limiting block is respectively fixed on both sides of the top surface of the front short side of the screen movable bottom plate.

[0017] The position adjustment system of the printing head on the photovoltaic screen printing machine of the present invention has the following characteristics:

[0018] 1. The position adjustment system of the present invention uses three mobile support seats driven by servo motors and a rotating plane of a fixed support seat as four support points to form X-axis, Y-axis and T-axis actuators integrated into the same coordinate plane. There is no error in the basic coordinate system, which is consistent with the benchmark of the data detected by the visual inspection device, so that the deviation caused by the mobile bottom plate of the screen will be greatly reduced;

[0019] 2. The center position of the T-axis in the position adjustment system of the present invention can be set arbitrarily in the coordinate plane, which can compensate for the deviation of the center position of the graphics generated in different printing processes, greatly improving the printing registration accuracy between the printing head and the silicon crystal cell on the printing table. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a perspective view of a photovoltaic screen printing machine according to the present invention;

[0021] Figure 2 is a perspective view of a position adjustment system of a printing head on a photovoltaic screen printing machine of the prior art;

[0022] Figure 3 is a perspective view of a position adjustment system of a printing head on a photovoltaic screen printer of the present invention;

[0023] Figure 4 It is a perspective view of the position adjustment system of the present invention without the screen moving bottom plate and the screen installation frame;

[0024] Figure 4a is a perspective view of a movable support seat in a position adjustment system of the present invention;

[0025] Figure 4b is a perspective view of a fixed support seat in the position adjustment system of the present invention;

[0026] Figure 4c is a perspective view of a screen supporting cylinder in a position adjustment system of the present invention;

[0027] Figure 5 It is a perspective view of the position adjustment system of the present invention without the screen moving bottom plate;

[0028] Figure 6 It is a perspective view of the position adjustment system of the present invention after removing the two upper guide strips on the screen moving bottom plate;

[0029] Figure 7 is a perspective view of a screen mounting frame in a position adjustment system of the present invention when viewed from above;

[0030] Figure 7a It is a vertical cross-sectional view of the installation structure of the screen installation frame in the position adjustment system of the present invention;

[0031] Figure 8 It is a schematic diagram of the position adjustment system of the printing head on the photovoltaic screen printing machine of the present invention.

[0032] Fig. 9 1 is a plan view of four adjustment conditions of the position adjustment system of the present invention. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with the accompanying drawings.

[0034] See also Figures 3 to 7a In conjunction with Figure 1 The position adjustment system of the printing head on the turntable photovoltaic screen printer of the present invention involves a turntable photovoltaic screen printer comprising a workbench 1, a work turntable 2, a visual inspection device 4 and two screen printing heads 5, 6;

[0035] The position adjustment system of the printing head 6 includes a base plate 60 , three movable support seats 61 , a fixed support seat 62 , two screen supporting cylinders 63 , a screen moving bottom plate 64 and a screen mounting frame 65 .

[0036] The substrate 60 is a rectangular plate with a rectangular through hole in the middle and an outer frame 601 around it. The substrate 60 is installed on the top surface of the workbench 1 through a Z-axis adjustment mechanism. An inner frame 602 is provided on the top surface of the substrate 60 along the four sides of the through hole. A rectangular channel with two X-axis channels 60x and two Y-axis channels 60y is formed between the inner frame 602 and the outer frame 601.

[0037] Three movable support seats 61 are installed one by one in the middle of an X-direction channel 60x and the middle of two Y-direction channels 60y of the substrate 60; each movable support seat 61 includes a mechanism base plate 610, a pair of lower cross roller guides 611 installed on the top surface of the mechanism base plate 610, a lower moving block 612 installed on the lower cross roller guide 611, a ball nut 616 connected to the lower moving block 612, a ball screw 617 installed on the ball nut 616, a driving motor 619 connected to the ball screw 617 through a coupling 618, a pair of upper cross roller guides 613 installed on the top surface of the lower moving block 612 and perpendicular to the pair of lower cross roller guides 611, an upper moving block 614 installed on the upper cross roller guide 613 and a cross roller bearing 615 installed in the center of the top surface of the upper moving block 614, and the upper moving block 614 is fixedly connected to the outer ring of the cross roller bearing 615.

[0038] The fixed support seat 62 is installed in the middle of another X-direction channel 60x of the base plate 60, and the fixed support seat 62 includes a mechanism base plate 610, a pair of lower cross roller guides 611 installed on the top surface of the mechanism base plate 610, a lower moving block 612 installed on the lower cross roller guides 611, a pair of upper cross roller guides 613 installed on the top surface of the lower moving block 612 and perpendicular to the pair of lower cross roller guides 611, an upper moving block 614 installed on the upper cross roller guides 613 and a cross roller bearing 615 installed in the center of the top surface of the upper moving block 614, and the upper moving block 614 is fixedly connected to the outer ring of the cross roller bearing 615.

[0039] Two screen supporting cylinders 63 are installed in two X-direction channels 60x in a one-to-one correspondence, and a conical head 630 is installed at the center of the top surface of the piston rod of each screen supporting cylinder 63;

[0040] The screen moving base plate 64 is a rectangular frame plate and is installed on the inner ring of the cross roller bearing 615 on the top of the three moving support seats 61 and the inner ring of the cross roller bearing 615 on the top of the fixed support seat 64 by screws; a guide hole 640 coaxial with the piston rods of the two screen support cylinders 63 is respectively opened on the two long sides of the screen moving base plate 64, so that the piston rods of the two screen support cylinders 63 are inserted into the two guide holes one by one when they are extended at the same time; an upper guide strip 641 with an L-shaped cross section is respectively installed on the top surface of the two long sides of the screen moving base plate 64 by screws; a limit block 642 is respectively fixed on both sides of the top surface of the front short side of the screen moving base plate 64.

[0041] A lower guide bar 651 with an L-shaped cross-section is fixed to the bottom surface of each of the two long sides of the screen mounting frame 65. The horizontal portions of the two lower guide bars 651 are correspondingly located at the bottom of the horizontal portions of the two upper guide bars 641. The horizontal portions of the two lower guide bars 651 each have an embedding groove 650 that matches the conical heads 630 on the two screen supporting cylinders 63. The screen mounting frame 65 is mounted on the top surface of the screen moving base plate 64 and is clamped with the two conical heads 630 that pass through the two guide holes on the screen moving base plate 64 through the two embedding grooves 650.

[0042] The position adjustment system of the printing head on the rotary disk photovoltaic screen printer of the present invention comprises:

[0043] The two upper guide bars 641 on the screen moving bottom plate 64 and the two lower guide bars 651 on the screen mounting frame 65 facilitate quick installation of the screen mounting frame 65 , so that the two embedding grooves on the screen mounting frame 65 are accurately coaxial with the piston rods of the two screen supporting cylinders 63 .

[0044] A screen is installed in the inner hole of the two upper guide strips 641 and the screen installation frame 65, and the screen has the required pattern for printing. When replacing the screen, the piston rods of the two screen support cylinders 63 are retracted to make the two conical heads 630 withdraw from the two embedded grooves 650 on the screen installation frame 65 one by one, and then the screen installation frame 65 is withdrawn backward along the two upper guide strips 641 on the screen moving bottom plate 64. After the screen is replaced, the screen installation frame 65 is moved forward along the two upper guide strips 641 on the screen moving bottom plate 64 until the front end surface of the screen installation frame 65 touches the fixing on the screen moving bottom plate 64. The two limit blocks 642 on the movable bottom plate 64, at this time, the two embedding grooves on the screen mounting frame 65 are just coaxial with the piston rods of the two screen supporting cylinders 63, and the piston rods of the two screen supporting cylinders 63 are controlled to extend, so that the two conical heads 630 are embedded in the two embedding grooves 650 on the screen mounting frame 65 one by one, and the piston rods of the two screen supporting cylinders 63 are also inserted into the two guide holes on the screen moving bottom plate 64 one by one, so that the screen mounting frame 65 is also installed on the screen moving bottom plate 64, and moves and rotates with the screen moving bottom plate 64.

[0045] The position adjustment system of the printing head on the turntable photovoltaic screen printing machine of the present invention includes three movable support seats 61. When the driving motor 619 provides power, the rotation of the ball screw 616 is converted into a linear movement of the ball nut 617 on the ball screw 617, thereby driving the lower moving block 612 and the upper cross roller guide 613, the upper moving block 614 and the cross roller bearing 615 installed on the lower moving block 612 to move axially along the ball screw 617 on the lower cross roller guide 611; the upper moving block 614 can passively move along the upper cross roller guide 613 and the direction perpendicular to the ball screw 617 with the cross roller bearing 615, and the cross roller bearing 615 can rotate around the center. The fixed support seat 62, the upper and lower moving blocks 612, the upper cross roller guide rail 613, the upper moving block 614 and the cross roller bearing 615 installed on the lower moving block 612 move passively on the lower cross roller guide rail 611; the upper moving block 614 and the cross roller bearing 615 can move passively along the upper cross roller guide rail 613 and the direction perpendicular to the ball screw 617, and the cross roller bearing 615 can rotate around the center. The three moving support seats 61 and the one fixed support seat 62 constitute the four supporting points A, B, C, and D of the screen moving bottom plate 64.

[0046] Please see again Figure 8 and Fig. 9 The working principle of the position adjustment system of the printing head on the rotary disk photovoltaic screen printing machine of the present invention in the following four adjustment situations is as follows:

[0047] 1. When the visual inspection device 4 of the printer detects that the center of the screen and the silicon crystal cell on the printing table are not aligned and there is an X-axis position deviation (see Fig. 9 a), when the visual processing system gives the adjustment data, the graphics on the screen on the printing head need to be moved in the X-axis direction. The driving motors 619 of the two movable support seats 61 installed in the two Y-direction channels 60y of the substrate 60 in a one-to-one correspondence do not provide power, the brake is locked, and the driving motor 619 of the movable support seat 61 (support point A) installed in an X-direction channel 60x of the substrate 60 converts the data given by the visual processing system in combination with the pitch of the ball screw 617, and rotates a certain number of circles according to the conversion result. At this time, the entire screen moving base plate 64 and the screen mounting frame 65 on which it has been positioned move as a whole in the X-axis direction, and the other two support points B, C and support point D follow (see Figure 8 ).

[0048] 2. When the visual inspection device 4 of the printer detects that the center of the screen and the silicon crystal cell on the printing table are not aligned and there is a Y-axis position deviation (see Fig. 9 b), when the visual processing system gives adjustment data and needs the graphics on the screen to move in the Y-axis direction, the drive motor 619 of the mobile support seat 61 (support point A) installed in an X-direction channel 60x of the substrate 60 does not provide power, the brake is locked, and the two drive motors 619 of the mobile support seat 61 installed in the two Y-direction channels 60y of the substrate 60 corresponding to each other convert the data given by the visual processing system in combination with the pitch of the ball screw 617, and rotate the same number of circles according to the conversion result. At this time, the entire screen moving base plate 64 and the screen mounting frame 65 that has been positioned on it move in the Y-axis direction as a whole, and the other two support points A and D follow (see Figure 8 ).

[0049] 3. When the visual inspection device 4 of the printer detects that the center of the screen and the silicon crystal cell on the printing table are not aligned and there is an angle deviation (see Fig. 9 c), when the visual processing system gives the adjustment data and requires the graphics on the screen to rotate around the T axis, the driving motors 619 of the three moving support seats 61 convert the data given by the visual processing system and the pitch of the ball screw 617, and rotate different circles according to the conversion results. At this time, the entire screen moving base plate 64 and the screen mounting frame 65 that has been positioned on it rotate around the central T axis of the screen moving base plate 64 as a whole. During the process, the four support points A, B, C, and D all have X-axis movement, Y-axis movement, and rotation around the center of their respective support points (see Figure 8 ).

[0050] 4. When the visual inspection device 4 of the printer detects that the center of the screen and the silicon crystal cell on the printing table are not aligned and there are both angle deviations, X-axis position deviations and Y-axis position deviations (see Fig. 9 d), when the visual processing system gives adjustment data and requires the graphics on the screen to move in the X-axis and Y-axis and rotate around the T-axis, the drive motors 619 of the three mobile support seats 61 convert the data given by the visual processing system in combination with the pitch of the ball screw 616, and rotate different numbers of circles according to the conversion results. At this time, the entire screen moving base plate 64 and the screen mounting frame 65 that has been positioned on it rotate as a whole around the central T axis of the screen moving base plate 64. During the process, the four support points A, B, C, and D all move in the X-axis and Y-axis directions, and rotate around the center of their respective support points (see Figure 8 ).

[0051] The position adjustment system of the printing head on the turntable photovoltaic screen printer of the present invention uses the rotating planes of three movable support seats 61 driven by servo motors and a fixed support seat 62 as four support points to form the rotating translation planes of the X-axis, Y-axis and T-axis; combined with the graphic data read by the visual detection device 4 and the deviation value of the analysis data, high-precision registration printing of the graphic is completed.

[0052] The above embodiments are only used to illustrate the present invention, rather than to limit the present invention. Those skilled in the relevant technical field may make various changes or modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also belong to the scope of the present invention and should be defined by the claims.

Claims

1. A position adjustment system for a printing head on a turntable photovoltaic screen printer, the turntable photovoltaic screen printer comprising a workbench, a work turntable, a visual inspection device and two screen printing heads; the position adjustment system for the printing head comprises a substrate, three movable support seats, a fixed support seat, two screen support cylinders, a screen movable bottom plate and a screen mounting frame; characterized in that: The substrate is a rectangular plate with a rectangular through hole in the middle and an outer frame around it, and the substrate is installed on the top surface of the workbench through a Z-direction adjustment mechanism, an inner frame is provided on the top surface of the substrate along the four sides of the through hole, and a rectangular channel with two X-direction channels and two Y-direction channels is formed between the inner frame and the outer frame; The three movable support seats are mounted one by one in the middle of one X-direction channel and the middle of two Y-direction channels of the base plate; each movable support seat comprises a mechanism bottom plate, a pair of lower cross roller guide rails mounted on the top surface of the mechanism bottom plate, a lower moving block mounted on the lower cross roller guide rails, a ball nut connected to the lower moving block, a ball screw mounted on the ball nut, a driving motor connected to the ball screw, a pair of upper cross roller guide rails mounted on the top surface of the lower moving block and perpendicular to the pair of lower cross roller guide rails, an upper moving block mounted on the upper cross roller guide rails, and a cross roller bearing mounted in the center of the top surface of the upper moving block; The fixed support seat is installed in the middle of another X-direction channel of the base plate, and the fixed support seat includes a mechanism bottom plate, a pair of lower cross roller guide rails installed on the top surface of the mechanism bottom plate, a lower moving block installed on the lower cross roller guide rails, a pair of upper cross roller guide rails installed on the top surface of the lower moving block and perpendicular to the pair of lower cross roller guide rails, an upper moving block installed on the upper cross roller guide rails, and a cross roller bearing installed in the center of the top surface of the upper moving block; Two screen supporting cylinders are installed in two X-direction channels one by one, and a conical head is installed at the center of the top surface of the piston rod of each screen supporting cylinder; The screen moving bottom plate is a rectangular frame plate and is installed on the inner rings of the cross roller bearings on the tops of the three moving support seats and the inner rings of the cross roller bearings on the tops of the fixed support seats by screws; a guide hole coaxial with the piston rods of the two screen support cylinders is respectively provided on the two long sides of the screen moving bottom plate, so that the piston rods of the two screen support cylinders are inserted into the two guide holes one by one when they are extended at the same time; A lower guide bar with an L-shaped cross-section is fixed to the bottom surface of each of the two long sides of the screen mounting frame, and a groove is provided on the horizontal portion of each of the two lower guide bars, which is matched with the conical heads on the two screen supporting cylinders. The screen mounting frame is installed on the top surface of the screen moving bottom plate and is clamped with the two conical heads that pass through the two guide holes on the screen moving bottom plate through the two grooves, which correspond one to one.

2. The position adjustment system for the printing head on the rotary disk photovoltaic screen printer according to claim 1, characterized in that: An upper guide bar with an L-shaped cross section and connected one by one with the two lower guide bars on the screen installation frame is fixed on the top surface of the two long sides of the screen moving bottom plate.

3. The position adjustment system for the printing head on a rotary disk photovoltaic screen printer according to claim 1 or 2, characterized in that: A limiting block is respectively fixed on both sides of the top surface of the front short side of the screen moving bottom plate.

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