|
An important part of the thick film screen printer
Date:2021/11/9 14:43:12 Hits:2820
The thick film screen printer is the same as the ordinary screen printer, which consists of three main parts: the screen, the print head, and the workbench.1. Ordinary screen printer1) The general print head assembly of the ordinary screen printer adopts the mode of guide rail + timing belt, and the power is mostly variable frequency motor or servo motor, and even the rodless cylinder is used for low requirements, which will not be described here.2) The screen plate is mostly made of aluminum frame (the cross section is a word frame, a Japanese word frame or a field frame) through welding, and the flatness is not accurate to the number at all. The screen plate lifting and lowering mostly adopts a crankshaft structure, and a geared motor is used to pass frequency conversion. To complete, or use servo motor + ball screw to vertically lift to complete.3) Workbenches are mostly made of stainless steel plates bonded together, or aluminum plates are made by a large water grinder, with a range of 1m×lm and a flatness of more than 0.1mm.An ordinary conventional screen printer composed of three parts, the error of each part is to preserve the area, that is, the so-called parallelism can not be preserved at all, and the overall flatness requirements for thick products have reached 0.01~0.02 Between mm, how can conventional screen printers meet the requirements of high-precision thick film.2. Advantages of thick film screen printerThe three major components of the thick film screen printer will be upgraded and changed according to the factors that affect the thick film. The parallelism between the print head and the screen must reach 0.02mm, and the parallelism between the screen and the worktable must also reach 0.02mm. Therefore, in response to this rigid requirement, Hengjin Intelligent Equipment has upgraded and modified the three major components of the thick film screen printing machine.1) Print head partThe running part of the print head adopts three parallel laying tracks, and three linear guide rails make up the gap with each other. The operation mode is ball screw + three guide rails parallel propulsion. The power adopts a servo motor with special adjustment and special treatment as the power. It is stable and parallel. The important factor of the head, the parallelism is guaranteed to be 0.01mm.2) Screen partThe screen part completely abandons the traditional welded screen frame. It adopts a cast-aluminum one-piece screen frame, and after aging treatment, the plane is firstly milled, and then the plane is ground with water to 0.02mm flatness. The overall lifting of the screen plate adopts a four-post servo lift, which is stable, fast and easy to control; each column of the four-post type is equipped with a dial indicator to display the data, and the data is visualized. You can see the screen lifting and lowering, which is 0 The display of 0 ensures that the distance between the screen and the substrate is fixed every time. This invariant directly affects the amount of slurry under the screen, thus affecting the film thickness.3) Workbench partThe workbench no longer uses the traditional stainless steel plate bonding type, and adopts the aluminum plate fine grinding type, hard oxidized, and has the characteristics of high flatness and not easy to scratch. The flatness is ±0.02mm, and the workbench is equipped with a horizontal adjustment structure around the workbench.Based on the transformation and upgrading of the three important parts, a quantitative index is obtained for the parallelism of the thick film screen printing machine: the parallelism between the print head and the screen is 0.02mm, and the parallelism between the screen and the worktable is 0.02 mm, the descending point of the print head and the screen plate is 0 to 0. After completing the above data, the products with stable film thickness can be printed.3. Cylindrical screen printerIn the screen printing of cylindrical products, such as stainless steel tubes, quartz tubes, ceramic tubes and other heat-generating tubular products, in addition to the above-mentioned three major factors of the print head, screen, and worktable, the design of the rotating fixture for the worktable is particularly important. NS.The traditional circular tube screen printing method is a gear saw blade structure, that is, the outer diameter of the gear is the same as the outer diameter of the product, and the number of teeth of the gear is an integral multiple of the circumference of the product, and then select the appropriate modulus, and use the motion of the screen to drive the saw blade. , So that the rack drives the gear to rotate, and the gear drives the product to rotate synchronously through the clamp.As the structural composition of the intelligent screen printer, this method obviously cannot be adapted to the printing of modern thick film round tubes. After unremitting efforts and experiments, Guangdong Hengjin intelligent equipment adopts the method of optical fiber positioning, according to the characteristics of various products, and various tubular manufacturing processes, in line with the purpose of reducing the production cost of thick film manufacturing enterprises and compressing the manufacturing process, research and development A new type of general-purpose rotating structure for cylindrical and round tubes is developed.1) The transmission structure of servo motor + synchronous wheel + synchronous belt is adopted to reduce different gear problems in manufacturing, and the servo motor can be adjusted for suitability according to the running speed of the screen or print head.2) Because the product process requires multiple printing to complete, which involves a problem of alignment, stainless steel tubes can be aligned by notching (it will increase the process); but quartz tubes and ceramic tubes cannot be completed. The gap is positioned and the gap error exists, which will cause the error of the product to increase. The fiber positioning method is used to solve the problem of process positioning, that is, the color difference of each process is used as the positioning point. In this way, the time for manual feeding is greatly shortened, and the production process of notching is reduced, thereby making thick film The company reduced production costs.
|