An inkjet printer with a print position synchronous positioning function

Abstract

This invention relates to the field of inkjet printing technology and discloses an inkjet printer with synchronous printing position positioning function. The printer includes a printer body and a printing platform mounted on the printer body. The printer body is characterized by a crossbeam mounted on it. A carriage and a position encoder are mounted at one end of the crossbeam. The carriage reciprocates along the X-axis of the crossbeam, and the position encoder outputs pulses reflecting the precise position of the carriage. An inkjet printhead and a camera are mounted on the carriage. The camera is mounted at the front end of the inkjet printhead along the Y-axis. The other end of the crossbeam can move in a stepping motion along the Y-axis, enabling the camera and inkjet printhead to scan and print across the entire printing platform. This invention optimizes the specific installation position of the camera and the selection of key parameters in the structural design of an inkjet printer with synchronous printing position positioning function, reducing the use of fixing fixtures while ensuring printing accuracy.

Description

Technical Field

[0001] This invention relates to the field of inkjet printing technology, and more specifically to an inkjet printer with a synchronous positioning function for printing position. Background Technology

[0002] Before printing with an inkjet printer, you need to lay blank paper flat on the pre-set printing area of ​​the printing platform, transmit the text and images to be printed to the printer, select the appropriate number of passes according to the printing accuracy requirements, and the printer will print the text and images onto the paper according to the printing information.

[0003] If the document to be printed is laid flat on the printing platform and not within the pre-defined printing area, the printer will be unable to print effectively. The current solution is as follows:

[0004] One solution is to use a camera to photograph the entire printing area before each print run, then calculate the coordinates and angles of each registration position, generate a full-size print image based on the calculation results, and finally output it to the printer for printing. The drawback is that before each print run, it's necessary to wait for the camera to photograph the entire area and then calculate the position and angle of each item to be registered within that area. This process takes far longer than the actual printing time, resulting in low production efficiency.

[0005] Another solution is to use a printer to print only fixed items. According to the shape and size of the items, corresponding fixtures are set at fixed positions on the printing platform. When printing, the items to be printed are placed in the fixtures and printed, which is equivalent to pre-setting the printing area. The disadvantage is that the printer can only print corresponding parts, which has low application scope, and each printer needs to set fixtures, which reduces the utilization range of the printing platform.

[0006] Therefore, this invention proposes an inkjet printer with synchronous positioning function for printing position. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides an inkjet printer with a reasonable structural design and high printing efficiency, featuring synchronous positioning of the printing position.

[0008] The technical solution of the present invention is as follows:

[0009] An inkjet printer with synchronous printing position positioning function includes a printer body and a printing platform mounted on the printer body. A crossbeam is mounted on the printer body. A carriage and a position encoder are installed at one end of the crossbeam. The carriage reciprocates along the X-axis of the crossbeam, and the position encoder outputs pulses to reflect the precise position of the carriage. An inkjet printhead and a camera are mounted on the carriage. The camera is installed at the front end of the inkjet printhead in the Y-axis direction. The other end of the crossbeam can move in a stepping motion along the Y-axis direction, enabling the camera and inkjet printhead to scan and print across the entire printing platform. When the carriage moves, the inkjet printhead outputs ink droplets for printing, while the camera captures the printing area of ​​the subsequent pass and the computer calculates the overprinting coordinates and angles of the subsequent pass area to be printed.

[0010] Furthermore, one round trip of the carriage along the crossbeam in the X-axis direction is called one pass. Each time the carriage moves back and forth once, the crossbeam moves 1 / n of the inkjet printhead output width, where n is the number of passes. The larger the number of passes, the higher the printing accuracy.

[0011] Furthermore, the camera field of view satisfies: h>m+m / n, meaning the camera field of view is at least one step m / n greater than the current print width m, where h is the camera field of view height, m ​​is the inkjet printhead width, and n is the number of print passes.

[0012] Furthermore, if the physical center of the camera coincides with the height center of the field of view, then the distance z from the camera center to the printhead center should satisfy: m / 2n < z < (h+m) / 2, thereby ensuring that the camera detects the area of ​​the next pass to be printed in advance, where h is the height of the camera's field of view, m is the width of the inkjet printhead, n is the number of passes to be printed, and z is the distance from the camera center to the printhead center.

[0013] The working process of an inkjet printer with print position synchronization positioning function includes the following steps:

[0014] Printing initialization: The carriage returns to the origin, the print head exits the printing platform, and the camera's field of view covers the 0th line and subsequent lines of the printing platform.

[0015] Pass1: Transmits empty data. The carriage prints one pass without ink, which drives the movement of the printing carriage. At this time, the camera captures the printing area of ​​the subsequent Pass.

[0016] Pass2: Still transmits empty data, the carriage prints one pass without printing. At this time, the computer calculates the shooting data of the camera in Pass1. If the object to be printed is identified, the position information is transmitted, the printing carriage is driven to move forward, and the printing is guided to pass3 for printing. If the object to be printed is not identified, a blank printing image of a pass is transmitted, and the carriage is driven to move forward. At the same time, the camera captures the scene of the printing area of ​​the subsequent passes.

[0017] Pass3: Based on the calculation results of the image captured by Pass1, the print head is guided to print. At the same time, during the printing process, the computer calculates the data captured by Pass2, and the camera captures the printing area of ​​the subsequent pass while the current pass is moving.

[0018] Subsequent printing follows the same pattern as Pass3, until the entire printing platform is completed.

[0019] Furthermore, to ensure that the printing waiting time is 0, the image processing under a single pass should satisfy a≥b, where a is the printing time per pass and b is the image position processing time under a single field of view of the camera; that is, at the same time that the printing of pass2 ends, the computer has already processed and obtained the image information of pass3 taken when pass1 was printed.

[0020] Furthermore, the proportion of effective information captured by the camera in a single pass in the camera's field of view is t. To ensure that the system's printing waiting time is 0, b / (htn / m)≤a should be satisfied, where a is the printing time per pass, b is the image position processing time in a single field of view of the camera, h is the height of the camera's field of view, m is the width of the inkjet printhead, and n is the number of passes printed.

[0021] The beneficial effects of this invention are as follows:

[0022] This invention relates to the structural design of an inkjet printer with synchronous positioning function for printing position. It optimizes the specific installation position of the camera and the selection of key parameters, thereby reducing the use of fixing fixtures while ensuring printing accuracy.

[0023] This invention optimizes the method of performing positioning processing before printing, and realizes the synchronous design of inkjet printing and printing position positioning processing.

[0024] Compared with existing printing technologies, this invention greatly improves printing efficiency and has high industrial application value. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the present invention;

[0026] Figure 2 This is a top view of the structure of the present invention;

[0027] Figure 3 This is a schematic diagram of the working process of the present invention;

[0028] Figure 4 This is a schematic diagram of the inkjet printhead width m and camera field of view height h of the present invention;

[0029] Figure 5 This is a schematic diagram showing the distance between the camera center and the printhead center of the present invention;

[0030] Figure 6 This is a schematic diagram of the parameters in Embodiment 1 of the present invention;

[0031] Figure 7 This is a schematic diagram of the product to be printed and the overprinted pattern according to the present invention;

[0032] In the picture: 1. Printer body; 2. Printing platform; 3. Crossbeam; 4. Carriage; 5. Inkjet print head; 6. Camera. Detailed Implementation

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

[0034] like Figure 1 , 2 As shown, an inkjet printer with synchronous printing position positioning function includes a printer body 1 and a printing platform 2 mounted on the printer body 1. A crossbeam 3 is mounted on the printer body 1. A carriage 4 and a position encoder are mounted on one end of the crossbeam 3. The carriage 4 moves back and forth along the X-axis of the crossbeam, and the position encoder outputs pulses to reflect the precise position of the carriage. An inkjet printhead 5 and a camera 6 are mounted on the carriage 4. The camera 6 is mounted at the front end of the inkjet printhead 5 in the Y-axis direction. The other end of the crossbeam 3 can move in a stepping motion along the Y-axis direction, so that the camera 6 and the inkjet printhead 5 can scan and print to the entire printing area of ​​the printing platform.

[0035] The crossbeam 3 is installed above the printing platform 2. One end of the crossbeam 3 is fixed to the side slide plate and can slide along the linear guide rail. The carriage 4 is installed on the other side of the crossbeam 3. The carriage 4 slides along the crossbeam 3 in the X direction for inkjet printing. At the same time, the camera slides with the carriage to capture an image of size (camera field of view X sliding distance). The carriage slides with the crossbeam 3 in the Y direction along the vertical direction of the crossbeam.

[0036] An inkjet printer with synchronous positioning function for printing position, when the carriage 1 moves, the inkjet printhead 5 outputs ink droplets for printing, while the camera 6 captures the printing area of ​​the subsequent pass, and the computer calculates the overprint coordinates and angles of the subsequent pass area to be printed, which greatly improves printing efficiency.

[0037] To ensure the smooth operation of the entire printing process: inkjet printhead width m, number of print passes n, camera field of view height h, print time per pass a, image position processing time under a single camera field of view b, and distance z from the camera center to the printhead center.

[0038] The printer prints a width of m per pass, and the printer's step size is m / n per pass. Figure 4 As shown, the left image displays the print size information for the current pass, while the right image shows the print area for subsequent passes as captured by the camera. To ensure that the image captured by the camera can guide the print position information for the next pass after processing, the camera's field of view h must be greater than m + m / n, meaning the camera's field of view must be at least one step m / n wider than the current print width m. The extent to which the camera's field of view extends beyond the current print width when the camera's field of view is determined is based on the camera's mounting position.

[0039] The camera installation position is determined based on the camera's field of view height (h), the inkjet printhead width (m), and the number of print passes (n). For example... Figure 5 As shown, if the physical center of the camera coincides with the height center of the field of view, then the distance z from the center of the camera to the center of the print head should satisfy: m / 2n < z < (h+m) / 2, ensuring that the camera can detect the subsequent printable pass area in advance.

[0040] If the camera's field of view is large enough, the camera does not need to be installed on the right side of the print head, and can even be installed on the left side of the print head. However, the camera will capture too much already printed data that does not require positioning processing, which will reduce the use of camera resources and increase the amount of duplicate data for the computer to process.

[0041] After the print head finishes printing the current pass, if the computer cannot process the position information of the subsequent pass areas within this time, the printing carriage will stop and wait for the processing results. To ensure that the waiting time is 0, from the perspective of image processing under a single pass, a ≥ b must be satisfied. That is, at the same time that the printing of the current pass2 is completed, the computer has already processed and obtained the image information containing pass3 captured during the printing of pass1.

[0042] However, the camera's field of view is large, and the camera's shooting under a single pass may cover the image position information of subsequent multiple passes; if the useful information captured by the camera under a single pass accounts for t% of the camera's field of view, to ensure that the system waiting time is 0, b / (htn / m)≤a should be satisfied.

[0043] like Figure 3 As shown, the working process of an inkjet printer with synchronous printing position positioning function is as follows:

[0044] Printing initialization: The carriage returns to the origin, the print head exits the printing platform, and the camera's field of view covers the 0th line and subsequent lines of the printing platform.

[0045] Pass1: Transmits empty data. The carriage prints one pass without ink, which drives the movement of the printing carriage. At this time, the camera captures the printing area of ​​the subsequent Pass.

[0046] Pass2: Still transmits empty data, the carriage prints one pass without printing. At this time, the computer calculates the shooting data of the camera in Pass1. If the object to be printed is identified, the position information is transmitted, the printing carriage is driven to move forward, and the printing is guided to pass3 for printing. If the object to be printed is not identified, a blank printing image of a pass is transmitted, and the carriage is driven to move forward. At the same time, the camera captures the scene of the printing area of ​​the subsequent passes.

[0047] Pass3: Based on the calculation results of the image captured by Pass1, the print head is guided to print. At the same time, during the printing process, the computer calculates the data captured by Pass2, and the camera captures the printing area of ​​the subsequent pass while the current pass is moving.

[0048] Subsequent printing follows the same pattern as Pass3, until the entire printing platform is completed.

[0049] Example 1:

[0050] like Figure 6 , 7 As shown, the part is 20mm high, the inkjet printhead is 18mm wide, the number of print passes is 6, the camera field of view is 50mm high, the print time per pass is 2.5s, the image position processing time under the single field of view of the camera is 2s, and the distance between the camera and the printhead is 25mm. According to the parameter adjustment, the printed part is laid flat on the printing platform, with a distance of more than 3mm from the edge.

[0051] Printing begins. At this point, the initial distance between the print head and the printing platform is -6mm. The first set of empty data is transmitted, driving the printing carriage to slide along the x-axis to print empty data. At the same time, the camera acquires the placement information of the parts on the printing platform. The camera's initial field of view is 3-53mm on the y-axis of the printing platform. After printing is completed, the main beam steps one pass, which is 3mm.

[0052] In the second printing, the initial distance of the print head to the printing platform is -3mm. A set of empty data is transmitted, and the printing carriage is driven to slide along the x-axis to print empty space. At the same time, the computer processes the image information of 3-53mm on the printing platform obtained by the camera in the first printing, and locates the product position information that needs to be overprinted in this range. Meanwhile, the second field of view of the camera is 6-56mm on the y-axis of the printing platform.

[0053] During the third print, the ink cartridge just enters the printing platform. The part position information in the first 3-53mm camera image has been processed after one step print. If the position information of the product to be overprinted is detected, the position information is transmitted to the printer to drive the printing carriage to slide along the x-axis for printing; if there is no printing information, empty data is transmitted to drive the printer to ensure that the camera can capture a 9-59mm image.

[0054] The fourth printout covers the entire printing platform, and the process repeats the third printout.

[0055] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the technical solutions of the present invention. Any technical solution that can be implemented based on the above embodiments without creative effort should be considered to fall within the scope of protection of the patent of the present invention.

Claims

1. An inkjet printer with synchronous printing position positioning function, comprising a printer body and a printing platform disposed on the printer body, characterized in that, The printer body is equipped with a crossbeam; a carriage and a position encoder are installed at one end of the crossbeam. The carriage moves back and forth along the X-axis of the crossbeam, and the position encoder outputs pulses to reflect the precise position of the carriage; an inkjet printhead and a camera are installed on the carriage. The camera is installed at the front end of the inkjet printhead in the Y-axis direction, and the other end of the crossbeam can move in a stepping motion along the Y-axis direction, so that the camera and inkjet printhead can scan and print on the entire printing platform; As the carriage moves, the inkjet printhead outputs ink droplets for printing, while the camera captures the printing area of ​​the subsequent pass and the computer calculates the overprint coordinates and angles of the subsequent pass area to be printed. The camera field of view satisfies: h>m+m / n, that is, the camera field of view is at least one step m / n more than the current print width m, where h is the height of the camera field of view, m is the width of the inkjet print head, and n is the number of print passes. If the physical center of the camera coincides with the height center of the field of view, then the distance z between the camera center and the printhead center should satisfy: This ensures that the camera can detect the area of ​​the next pass to be printed in advance.

2. An inkjet printer with synchronous positioning function for printing position according to claim 1, characterized in that, One round trip of the carriage along the crossbeam in the X-axis direction is called one pass. Each time the carriage moves back and forth once, the crossbeam moves 1 / n times the output width of the inkjet printhead, where n is the number of passes. The larger the number of passes, the higher the printing accuracy.

3. The working process of an inkjet printer with synchronous positioning function for printing position according to claim 1, characterized in that, Including the following steps: Printing initialization: The carriage returns to the origin, the print head exits the printing platform, and the camera's field of view covers the 0th line and subsequent lines of the printing platform. Pass1: Transmits empty data. The carriage prints one pass without ink, which drives the movement of the printing carriage. At this time, the camera captures the printing area of ​​the subsequent Pass. Pass2: Still transmits empty data, the carriage prints one pass without printing. At this time, the computer calculates the shooting data of the camera in Pass1. If the object to be printed is identified, the position information is transmitted, the printing carriage is driven to move forward, and the printing is guided to pass3 for printing. If the object to be printed is not identified, a blank printing image of a pass is transmitted, and the carriage is driven to move forward. At the same time, the camera captures the scene of the printing area of ​​the subsequent passes. Pass3: Based on the calculation results of the image captured by Pass1, the print head is guided to print. At the same time, during the printing process, the computer calculates the data captured by Pass2, and the camera captures the printing area of ​​the subsequent pass while the current pass is moving. Subsequent printing follows the same pattern as Pass3, until the entire printing platform is completed.

4. The working process of an inkjet printer with synchronous positioning function for printing position according to claim 3, characterized in that, To ensure zero print wait time, image processing in a single pass should meet the following requirements. , where a is the printing time per pass and b is the image position processing time under a single field of view of the camera.

5. The working process of an inkjet printer with synchronous positioning function for printing position according to claim 4, characterized in that, The effective information captured by the camera in a single pass accounts for t% of the camera's field of view. To ensure that the entire system's printing wait time is 0, the following should be satisfied: .

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