A thick film printer

Abstract

The present application belongs to the technical field of printing, and particularly relates to a thick film printing machine, which comprises a printing device, a printing platform, a screen, a machine box, a machine frame and a controller. The printing device comprises a doctor blade assembly and a doctor blade control mechanism. The doctor blade control mechanism cooperates with the doctor blade assembly. The doctor blade assembly comprises a doctor blade. The doctor blade control mechanism comprises a doctor blade adjusting assembly, a doctor blade lifting assembly and a doctor blade pressing assembly. The doctor blade assembly can cooperate with the screen under the action of its own gravity. The doctor blade lifting assembly is used for lifting the doctor blade assembly upward. The doctor blade pressing assembly is used for increasing the pressure between the doctor blade and the screen. The doctor blade adjusting assembly is used for lifting the doctor blade upward and reducing the pressure between the doctor blade and the screen. The pressure information of the doctor blade acting on the screen can be fed back to the controller. The printing platform can feed back the pressure information of the substrate placed thereon to the controller. Compared with the prior art, the printing device cooperates with the printing platform to realize the accurate adjustment of the substrate printing.

Description

Technical Field

[0001] This invention relates to the field of printing technology, and more specifically, to a thick film printing machine. Background Technology

[0002] Thick film printing machines are specialized equipment used to print circuits, patterns, and resistors on electronic components using a substrate printing method. They mainly include printing equipment, screen printing, printing table, frame, and control device.

[0003] During operation, the printing press applies pressure to the screen using a squeegee on the printing device, thereby printing ink onto the substrate of the printing table, thus achieving printing on the substrate. After prolonged operation, the tension of the screen itself will change to a certain extent, which means that simply adjusting the pressure applied by the printing device is far from sufficient to adjust the printing accuracy of the printing press.

[0004] Chinese Patent ZL2012105631167, filed by the applicant on December 21, 2012, discloses a squeegee control mechanism for a screen printing machine, including a base, a squeegee assembly, an ink coating assembly, a squeegee lifting mechanism, and a squeegee pressure applying mechanism. The squeegee pressure applying mechanism uses a worm gear mechanism to drive a torsion spring for pressure adjustment, which is convenient. The worm gear has a self-locking function, improving the stability of the printing pressure. The squeegee lifting mechanism uses a cam, a swing rod, a pull rod, a four-bar linkage, a slide rail, and rollers to drive the squeegee to rise and fall.

[0005] In the above technical solution, the lifting mechanism and the pressure-applying mechanism work together to decompose the lifting motion of the squeegee and the pressure transmission into two separate mechanisms. This ensures that the resistance of the lifting motion of the squeegee does not affect the printing pressure, thus improving the controllability of the mechanism. This structure has been proven to be stable and reliable through more than ten years of large-scale use. This structure is mainly used in thick-film printed sensors and printed hybrid integrated circuits, where the printing area is relatively small, and this mechanism can meet the requirements. With the advancement of technology, the required printing area is getting larger and larger, and the above mechanism is inadequate for printing larger areas, such as LTCC and wafers larger than 8 inches.

[0006] Currently, there are basically two types of CCD automatic alignment stages: UVW type and XYθ type. Both types of alignment stages use three motors to drive ball screw nuts to achieve alignment by moving in three degrees of freedom in the plane. The movement accuracy of this type of alignment stage depends entirely on the accuracy of the ball screw nuts. If the alignment stage components do not need to move after the alignment movement is completed, and the subsequent work can be completed, then this alignment method is feasible.

[0007] However, tabletop screen printing machines require movement; the alignment stage, after achieving alignment at the alignment station, needs to quickly move to the printing station for positioning. This rapid start-up and stopping back and forth causes significant impact. The lead screw and nut have a clearance, and the impact can cause positional misalignment, especially after prolonged use and wear, which increases the clearance. If an alignment accuracy of <5μm is required, the clearance between the lead screw and nut may exceed 5μm. Therefore, general-purpose CCD automatic alignment stages cannot meet high-precision printing requirements or have a very short service life. Summary of the Invention

[0008] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a thick film printing machine that solves the problems of the claimed technology.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A thick film printing machine includes a printing device, a printing table, a screen, a machine housing, a frame, and a controller. The printing table is slidably connected to the machine housing, the frame is fixed to the machine housing, the printing device is connected to the frame, and the screen is placed between the printing device and the printing table. The printing device includes a squeegee assembly and a squeegee control mechanism. The squeegee control mechanism cooperates with the squeegee assembly. The squeegee assembly includes a squeegee. The squeegee control mechanism includes a squeegee adjustment component, a squeegee lifting component, and a squeegee pressing component. The squeegee assembly can engage the squeegee with the screen under its own weight. The squeegee lifting component is used to lift the squeegee assembly upwards, the squeegee pressing component is used to increase the pressure between the squeegee and the screen, and the squeegee adjustment component is used to lift the squeegee upwards and reduce the pressure between the squeegee and the screen. The pressure information of the squeegee acting on the screen can be fed back to the controller.

[0011] The printing station includes a base and a platen. The substrate can be placed on the platen, and the printing station can sense the pressure exerted by the substrate on the platen and feed this pressure information back to the controller.

[0012] Furthermore, the scraper assembly also includes a shaft, a rotating plate, and a mounting base. The shaft is fixed to the mounting plate, the rotating plate is rotatably connected to the shaft, the mounting base is fixed to the rotating plate, and the scraper is detachably connected to the mounting base.

[0013] The scraper adjustment assembly includes a base, an adjustment seat, a support, and an adjustment head. The adjustment seat is fixed on the mounting base and has an adjustment space and a threaded hole. The base is fixed on the base and extends into the adjustment space. The support is placed in the adjustment space and fixed on the base. The adjustment head is screwed into the threaded hole, and the end of the adjustment head extends into the adjustment space and cooperates with the support.

[0014] The scraper lifting assembly includes a first cylinder fixed on a base and a lifting head connected to the output end of the first cylinder. The lifting head cooperates with the mounting base.

[0015] Furthermore, the scraper pressing assembly is provided in two sets and is placed on both sides of the base respectively. The scraper adjusting assembly is placed between the two sets of scraper pressing assemblies. The base is provided with two pressure seats that cooperate with the two sets of scraper pressing assemblies one by one.

[0016] The scraper pressing assembly includes a fixed base, a torsion spring, a worm gear, a worm, and a pressure transmission seat. The fixed base is fixed to the base, the worm gear and worm are placed on the fixed base and mesh with each other, the torsion spring is sleeved on the shaft of the worm gear, and the pressure transmission seat is sleeved on the front end of the shaft of the worm gear. One end of the torsion spring is fixed to the pressure transmission seat, and the other end of the torsion spring is fixed to the shaft of the worm gear. The end of the pressure transmission seat can be pressed onto the pressure bearing seat.

[0017] Furthermore, a first pressure sensor is provided on the pressure bearing seat, and the pressure transmission seat cooperates with the first pressure sensor; a second pressure sensor is embedded in the support, the second pressure sensor is placed on the base, and the second pressure sensor cooperates with the adjustment head.

[0018] Furthermore, at least one fourth pressure sensor is provided between the base and the platform.

[0019] Furthermore, a positioning plate is fixed on the platform. The positioning plate is made of metal. A positioning mechanism is fixed on the base. The positioning mechanism includes a cylinder and a limiting head that are fixedly connected to each other. The limiting head includes a limiting groove. The positioning plate extends into the limiting groove. The output end of the cylinder can extend into the limiting groove and press the positioning plate against the limiting head.

[0020] Furthermore, the platform is movably connected to the base, the platform can reciprocate in the x and y directions, and the platform can rotate, the platform can drive the positioning piece to move within the limiting groove.

[0021] Furthermore, the printing table includes a motor, a moving nut, and a slider. The motor's lead screw is rotatably connected to the moving nut, the moving nut is fixedly connected to the slider, and the slider is slidably connected to the base. A tension spring is fixed to the fixed side of the motor lead screw and the slider side.

[0022] Furthermore, the printing table also includes a mounting frame and a support plate, with the mounting frame fixed to the table and the support plate fixed to the mounting frame.

[0023] Furthermore, a positioning seat is provided between the scraper and the mounting base. Both the positioning seat and the scraper are rotatably connected to the mounting base. The scraper is engaged with the positioning seat. An adjusting handle is provided on each side of the mounting base. The two adjusting handles are threadedly connected to the mounting base, and the ends of the adjusting handles abut against the positioning seat.

[0024] By adopting the above technical solution, the beneficial effects of the present invention are as follows:

[0025] 1. The printing device can apply pressure precisely to the screen and the substrate (ceramic sheet, etc.), and the printing table can also sense the pressure of the ceramic sheet placed on it at all times. The two work together to achieve precise adjustment of substrate printing.

[0026] 2. The squeegee assembly is raised and released by the squeegee lifting assembly, pressure is applied to the released squeegee assembly by the squeegee pressing assembly, and the squeegee adjusting assembly is raised to reduce the pressure exerted by the squeegee assembly on the screen. The pressure on the screen = the weight of the squeegee assembly itself + the pressure applied by the squeegee pressing assembly - the upward force of the squeegee adjusting assembly. This setting allows for more precise adjustment of the pressure exerted by the squeegee on the screen, thereby greatly improving the printing accuracy of the printing machine.

[0027] 3. The structure of this doctor blade control device is more streamlined, which can more effectively and directly adjust the precision of the doctor blade. At the same time, it can also know the pressure applied by the doctor blade to the screen over time, thereby realizing real-time adjustment of the doctor blade pressure and ensuring the precision of the printing press.

[0028] 4. When the drive device moves the printing table back and forth on the frame, the positioning mechanism and the positioning plate cooperate to fix the table plate stably, so that the substrate placed on the carrier plate is not easily moved due to impact, thereby avoiding the impact on the printing accuracy of the substrate.

[0029] 5. Even after long-term use causes the moving nut to wear, it can still ensure that the nut is always close to one side of the screw thread, so that even after wear, it will not affect the positioning accuracy. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention.

[0031] Figure 2 This is a schematic diagram of the printing apparatus.

[0032] Figure 3 This is a schematic diagram of the exploded structure of a printing apparatus.

[0033] Figure 4 This is a partial structural diagram of the printing apparatus.

[0034] Figure 5 This is a top view of the printing plate structure.

[0035] Figure 6 This is a front view structural diagram of the printing plate.

[0036] Figure 7 This is a schematic diagram of the exploded structure of the printing plate. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0039] The thick film printing machine includes a printing device 1, a printing table 2, a screen 3, a CCD camera 4, a housing 5, a frame 6, and a controller 7. The printing table 2 is slidably connected to the housing 5, the frame 6 is fixed on the housing 5, the printing device 1 is connected to the frame 6, and the screen 3 is placed between the printing device 1 and the printing table 2. The substrate can be placed on the printing table 2, and the printing table 2 can sense the pressure of the substrate acting on the table plate 22 and feed back the pressure information to the controller 7.

[0040] When the printing press is working, the substrate is first placed on the table 22. Then, the CCD camera 4 takes a picture of the substrate and feeds the information back to the controller 7. The controller 7 then controls the table 22 to adjust and calibrate the substrate until the substrate is correctly positioned. After that, the printing table 2 slides on the machine housing 5 and moves to the bottom of the printing device 1. Then, the printing device 1 performs inking and printing, and finally completes the printing of the substrate. The pressure fed back to the controller 7 from the printing table 2 is equal to the weight of the substrate itself plus the pressure applied to the substrate by the printing device 1. The controller 7 can know the pressure acting on the substrate at all times. Therefore, even if the tension of the screen 3 changes due to long-term pressure, the pressure of the printing device 1 can be adjusted accordingly to ensure the accuracy of the substrate printing.

[0041] The printing apparatus 1 includes a mounting plate 11, an ink coating assembly 16, a doctor blade assembly 12, and a doctor blade control mechanism. The doctor blade control mechanism cooperates with the doctor blade assembly 12. The doctor blade assembly 12 includes a doctor blade 121, a shaft 122, a rotating plate 123, and a mounting base 124. The doctor blade control mechanism includes a doctor blade adjustment assembly 15, a doctor blade lifting assembly 13, and two sets of doctor blade pressing assemblies 14. The two sets of doctor blade pressing assemblies 14 are respectively placed on both sides of the mounting plate 11, and the doctor blade adjustment assembly 15 is placed between the two sets of doctor blade pressing assemblies 14. The mounting base 124 is provided with two pressure seats 125 that cooperate with the two sets of doctor blade pressing assemblies 14 one by one.

[0042] The controller 7 can control the movement of the doctor blade assembly 12, the doctor blade control mechanism, and the inking assembly 16. After the printing press starts working, the doctor blade lifting device starts and releases the doctor blade assembly 12. Under its own weight and the combined action of the two sets of doctor blade pressing assemblies 14, the doctor blade assembly 12 rotates and presses down around the shaft 122 until the doctor blade contacts the screen 3. By adjusting the two sets of doctor blade pressing assemblies 14, the pressure between the doctor blade 121 and the screen 3 is increased. The doctor blade adjusting assembly 15 lifts the doctor blade upward to reduce the pressure between the doctor blade and the screen 3. This adjustment pressure is relatively small and is used for fine-tuning the pressure of the doctor blade on the screen 3, thereby improving the accuracy of the pressure of the doctor blade on the screen 3. After the doctor blade lifting assembly 13 finishes working, it can lift the doctor blade assembly 12 upward, so that the doctor blade is away from the screen 3, preparing for the next printing.

[0043] The shaft 122 is fixed on the mounting plate 11, the rotating plate 123 is rotatably connected to the shaft 122, the mounting base 124 is fixed on the rotating plate 123, the scraper 121 is detachably connected to the mounting base 124, a positioning seat 127 is provided between the scraper 121 and the mounting base 124, both the positioning seat 127 and the scraper 121 are rotatably connected to the mounting base 124, the scraper 121 is snapped into the positioning seat 127, an adjusting handle 126 is provided on each side of the mounting base 124, the two adjusting handles 126 are threadedly connected to the mounting base 124, and the ends of the adjusting handles 126 abut against the positioning seat 127;

[0044] After the scraper lifting assembly 13 releases the scraper assembly 12, the rotating plate 123 drives the scraper 121 to rotate downward until the bottom of the scraper 121 contacts the wire mesh 3. The tilt of the scraper 121 can be adjusted by the positioning seat 127 and the two adjusting handles 126, thereby realizing the cooperation between the scraper 121 and the wire mesh 3. The scraper 121 can be disassembled and connected, which facilitates the disassembly and replacement of the scraper 121.

[0045] The scraper lifting assembly 13 includes a first cylinder 131 fixed on the base 21 and a lifting head 132 connected to the output end of the first cylinder 131. The lifting head 132 cooperates with the mounting base 124.

[0046] After the scraper lifting assembly 13 is activated, the output end of the first cylinder 131 moves downward, thereby causing the lifting head 132 to move downward and disengage from the mounting base 124, thus releasing the scraper assembly 12 and enabling the scraper to cooperate with the wire mesh 3; the first cylinder 131 drives the lifting head 132 to move upward, and the lifting head 132 can lift the mounting base 124, so that the scraper assembly 12 is reset, and then the scraper moves away from the wire mesh 3.

[0047] The scraper pressing assembly 14 includes a fixed base 141, a torsion spring 142, a worm gear 143, a worm 144, and a pressure transmission seat 145. The fixed base 141 is fixed on the mounting plate 11. The worm gear 143 and the worm 144 are placed on the fixed base 141 and mesh with each other. The torsion spring 142 is sleeved on the shaft of the worm gear 143. The pressure transmission seat 145 is sleeved on the front end of the shaft of the worm gear 143. One end of the torsion spring 142 is fixed to the pressure transmission seat 145, and the other end of the torsion spring 142 is fixed to the shaft of the worm gear 143. The end of the pressure transmission seat 145 can be pressed onto the pressure bearing seat 125. The pressure bearing seat 125 is provided with a first pressure sensor 146, and the pressure transmission seat 145 cooperates with the first pressure sensor 146.

[0048] A knob 147 can be provided on the top of the worm gear 144. By turning the knob 147, the worm gear 144 drives the worm wheel 143 to rotate, which causes the torsion spring 142 to tighten or loosen, thereby adjusting the pressure of the pressure transmission seat 145 on the pressure bearing seat 125, that is, adjusting the pressure of the doctor blade pressing down. The pressure applied by the doctor blade 121 to the screen 3 is fed back to the controller 7 through the first pressure sensor 146. The controller 7 displays the pressure information on the electronic screen of the printing machine, which is convenient for personnel to observe in real time and also facilitates the precise adjustment of the doctor blade pressure by the staff.

[0049] The scraper adjustment assembly 15 includes a base 151, an adjustment seat 152, a support 153, and an adjustment head 154. The adjustment seat 152 is fixed on the mounting base 124. The adjustment seat 152 has an adjustment space 1501 and a threaded hole 1502. The base 151 is fixed on the mounting plate 11 and extends into the adjustment space 1501. The support 153 is placed in the adjustment space 1501 and fixed on the base 151. The adjustment head 154 is screwed into the threaded hole 1502, and the end of the adjustment head 154 extends into the adjustment space 1501 and cooperates with the support 153. The support 153 has a second pressure sensor 155 embedded in it. The second pressure sensor 155 is placed on the base 151 and cooperates with the adjustment head 154.

[0050] When the pressure of the scraper is adjusted by the scraper adjustment assembly 15, the lower end of the adjustment head 154 is rotated to press against the support 153 until the adjustment seat 152 drives the scraper assembly 12 to move upward, thereby reducing the pressure of the scraper 121 on the screen 3; the upward pressure of the scraper adjustment assembly 15 is fed back to the controller 7 by the second pressure sensor 155 and displayed on the electronic screen.

[0051] The ink coating assembly 16 includes an ink coating blade 161, a blade holder 162, a second cylinder 163, and a third pressure sensor 164. The second cylinder 163 is fixed on the mounting plate 11. The output end of the second cylinder 163 is connected to the upper end of the third pressure sensor 164. The lower end of the third pressure sensor 164 is connected to the blade holder 162. The blade holder 162 is connected to the ink coating blade 161. The second cylinder 163 can drive the ink coating blade 161 to move up and down reciprocally.

[0052] When the inking assembly 16 is working, the second cylinder 163 starts and drives the blade holder 162 to move downward, thereby the blade holder 162 drives the inking blade 161 to move downward and cooperate with the screen 3 to prepare for inking; the third pressure sensor 164 can detect the pressure applied to the screen 3 by the inking blade 161 and display it on the electronic screen, so as to know whether there is ink on the screen 3 based on the real-time pressure information, thereby avoiding the printing machine from continuing to work when there is no ink on the screen 3; after the inking is completed, the second cylinder 163 drives the inking blade 161 to reset, so that the inking blade 161 moves upward away from the screen 3;

[0053] After the ink coating process is completed by the ink coating component 16, the ink coating component 16 can also cooperate with the squeegee component 12 to form a double squeegee structure, realize reciprocating printing on the substrate, and improve printing efficiency.

[0054] The printing table 2 includes a base 21, a table plate 22, a mounting frame 23, a support plate 24, a motor 25, a moving nut (not shown), a slider 26, a tension spring 27, and a fourth pressure sensor 29. The table plate 22 is placed on the base 21, the mounting frame 23 is fixed on the table plate 22, and the support plate 24 is fixed on the mounting frame 23. The table plate 22 is movably connected to the base 21. The printing table 2 adopts the structure of a UVW alignment platform. The base 21 has two motors 25 in the x-axis direction and one motor 25 in the y-axis direction. The two motors 25 in the x-axis direction can move the table plate 22 in the x-axis direction when they move synchronously, and the two motors 25 can rotate the table plate 22 when they move asynchronously. The motor 25 in the y-axis direction can move the table plate 22 in the y-axis direction.

[0055] The platform 22 can reciprocate in the x-axis and y-axis directions, and the platform 22 can rotate, so that the position of the substrate placed on the carrier plate 24 can be adjusted and calibrated to ensure the accuracy of the substrate during printing.

[0056] Four fourth pressure sensors 29 are provided between the base 21 and the platform 22, and the four fourth pressure sensors 29 are evenly arranged around the base 21, which can realize accurate sensing of the pressure on the substrate on the support plate 24.

[0057] The platform 22 is provided with four thin positioning pieces 221 made of metal around its perimeter, and the base 21 is also provided with four positioning mechanisms 222 around its perimeter. The four positioning pieces 221 and the four positioning mechanisms 222 correspond one to one. The positioning mechanism 222 includes a cylinder 2201 and a limiting head 2202 that are fixedly connected to each other. The limiting head 2202 includes a limiting groove 2203. The positioning piece 221 extends into the limiting groove 2203. The output end of the cylinder 2201 can extend into the limiting groove 2203 and press the positioning piece 221 against the limiting head 2202.

[0058] When the substrate is adjusted by moving the platform 22, the platform 22 drives the positioning piece 221 to move within the limiting groove 2203. After the substrate position is adjusted and calibrated, the output end of the cylinder 2201 moves upward and presses the positioning piece 221 into the limiting groove 2203, thereby fixing the platform 22 and achieving stable positioning of the substrate. This setting can ensure both substrate calibration and adjustment, as well as stable substrate positioning, resulting in better printing accuracy.

[0059] The lead screw of motor 25 is rotatably connected to the moving nut, the moving nut is fixedly connected to the slider 26, the slider 26 is slidably connected to the base 21, and the tension spring 27 is fixed between the fixed side of the lead screw of motor 25 and the side of the slider 26. With this setting, even if the moving nut wears down after long-term use, the nut can still be kept close to the side of the lead screw thread, so that even if it wears down, it will not affect the positioning accuracy.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included within the protection scope of the present invention.

Claims

1. A thick film printing machine, comprising a printing device, a printing table, a screen, a machine housing, a frame, and a controller, wherein the printing table is slidably connected to the machine housing, the frame is fixed to the machine housing, the printing device is connected to the frame, and the screen is placed between the printing device and the printing table, characterized in that... The printing apparatus includes a squeegee assembly and a squeegee control mechanism. The squeegee control mechanism cooperates with the squeegee assembly. The squeegee assembly includes a squeegee, and the squeegee control mechanism includes a squeegee adjustment component, a squeegee lifting component, and a squeegee pressing component. The scraper assembly can engage the scraper with the wire mesh under its own gravity. The scraper lifting assembly is used to lift the scraper assembly upward. The scraper pressing assembly is used to increase the pressure between the scraper and the wire mesh. The scraper adjusting assembly is used to lift the scraper upward and reduce the pressure between the scraper and the wire mesh. The pressure information of the scraper acting on the wire mesh can be fed back to the controller. The printing table includes a base and a platen. The substrate can be placed on the platen, and the printing table can sense the pressure exerted by the substrate on the platen and feed the pressure information back to the controller.

2. A thick film printing machine according to claim 1, characterized in that, The scraper assembly also includes a shaft, a rotating plate, and a mounting base. The rotating plate is rotatably connected to the shaft, the mounting base is fixed to the rotating plate, and the scraper is detachably connected to the mounting base. The scraper adjustment assembly includes a base, an adjustment seat, a support, and an adjustment head. The adjustment seat is fixed to the mounting base and has an adjustment space and a threaded hole. The base is fixed to the base and extends into the adjustment space. The support is placed in the adjustment space and fixed to the base. The adjustment head is screwed into the threaded hole, and the end of the adjustment head extends into the adjustment space and cooperates with the support. The scraper lifting assembly includes a first cylinder fixed on the base and a lifting head connected to the output end of the first cylinder. The lifting head cooperates with the mounting base.

3. A thick film printing machine according to claim 2, characterized in that, The scraper pressing assembly is provided in two sets and is respectively placed on both sides of the base. The scraper adjusting assembly is placed between the two sets of scraper pressing assemblies. The base is provided with two pressure-bearing seats that mate with the two sets of scraper pressing assemblies one by one. The scraper pressing assembly includes a fixed base, a torsion spring, a worm gear, a worm, and a pressure transmission seat. The worm gear and worm are placed on the fixed base and mesh with each other. The torsion spring is sleeved on the shaft of the worm gear, and the pressure transmission seat is sleeved on the front end of the shaft of the worm gear. One end of the torsion spring is fixed to the pressure transmission seat, and the other end of the torsion spring is fixed to the shaft of the worm gear. The end of the pressure transmission seat can be pressed onto the pressure bearing seat.

4. A thick film printing machine according to claim 3, characterized in that, The pressure-bearing seat is equipped with a first pressure sensor, and the pressure transmission seat cooperates with the first pressure sensor. The support is embedded with a second pressure sensor, which is placed on the base and cooperates with the adjustment head.

5. A thick film printing machine according to claim 1 or 4, characterized in that, At least one fourth pressure sensor is provided between the base and the platform.

6. A thick film printing machine according to claim 5, characterized in that, A positioning plate is fixed on the platform. The positioning plate is made of metal. A positioning mechanism is fixed on the base. The positioning mechanism includes a cylinder and a limiting head that are fixedly connected to each other. The limiting head includes a limiting groove. The positioning plate extends into the limiting groove. The output end of the cylinder can extend into the limiting groove and press the positioning plate against the limiting head.

7. A thick film printing machine according to claim 6, characterized in that, The platform is movably connected to the base, and the platform can reciprocate in the x-axis and y-axis directions. The platform can also rotate, and the platform can drive the positioning piece to move within the limiting groove.

8. A thick film printing machine according to claim 7, characterized in that, The printing table includes a motor, a moving nut, and a slider. The motor's lead screw is rotatably connected to the moving nut, the moving nut is fixedly connected to the slider, and the slider is slidably connected to the base. A tension spring is fixed to the fixed side of the motor lead screw and the slider side.

9. A thick film printing machine according to claim 3, characterized in that, The printing table also includes a mounting frame and a support plate. The mounting frame is fixed to the table, and the support plate is fixed to the mounting frame.

10. A thick film printing machine according to claim 1 or 4, characterized in that, A positioning seat is provided between the scraper and the mounting base. Both the positioning seat and the scraper are rotatably connected to the mounting base. The scraper is engaged with the positioning seat. An adjustment handle is provided on each side of the mounting base. The two adjustment handles are threadedly connected to the mounting base. The ends of the adjustment handles abut against the positioning seat.

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