KR20150042662A - Auto calibration method by using limit sensor on the 3D printer frame - Google Patents

Abstract

The present invention relates to a height calibration method using a limit sensor of a 3D printer. The present invention relates to a method for making a G-code to control the height of a designed file and a limit switch sensor for simply solving the calibration problem of a bed height which greatly influences quality when the 3D printer is used. The height calibration method using the limit sensor of the 3D printer according to the present invention automatically recognizes the height of the bed and attenuates errors.

Description

[0001] The present invention relates to a height calibration method using a limit sensor of a 3D printer,

Technology that can offset height difference with reference height by software using height sensor with limit sensor

The limit switch is a sensor used for position detection. When the object touches the contact part of the limit switch, the built-in switch is activated to execute the command entered by the software.

At present, the FDM type home desktop 3D printer operates in such a way that the filament type material is stacked on the bed according to the instruction of the software which reads the design file. At this time, if the bed is not leveled or the setting height and error are generated, the output is not outputted according to the desired shape or the bed is not attached frequently. Up to now, we have used a method of manually adjusting the height of the bed as a means of solving this problem. Although the height was adjusted by directly screwing or loosening the screws by putting the spring and the butterfly screw on the lower four corners of the bed whose height did not match, it took a long time and it was difficult to calibrate the height evenly over the whole part of the bed. We have devised a way to automatically recognize the bed height and offset the error to get out of the way of manually adjusting the bed height.

We inserted a command (G29 code) that recognizes the bed height in the existing firmware and applied a method that allows the limit switch to read the height value quantitatively. Instead of inserting code to move the bed to offset the height difference, the firmware used to adjust the height information on the output file to align with the bed and print the desired height of the output. The code names are as follows.

define X_EXTRUDER_OFFSET_FROM_Z_PROBE 35

define Y_EXTRUDER_OFFSET_FROM_Z_PROBE -14

define Z_EXTRUDER_OFFSET_FROM_Z_PROBE 7.10

Calculate the offset value by inserting the above code, and operate the limit switch system to measure the center height of the bed. Next, the position is obtained using the same method for measuring the height of the four corners, and then the difference from the middle height value is quantitatively obtained. And put the difference value into configuration.h code and modify output height information when generating gcode.

The height of the bed, which has a great influence on the quality of output, can be easily corrected by automatic calibration. With the aid of a leveling system, the height of the bed can be manually adjusted without trial and error, which saves time in setting the machine and reduces the effort of adjusting the height every time the output is renewed. In addition, quantitative error values for height differences can be obtained, allowing more accurate calibration.

Attach a limit switch under the drive plate of the three-printers and calculate the height difference from the reference height by letting the sensor read the height of the bottom surface. Calibrates the output height by the height difference.

Claims (2)

In order to more easily solve the calibration problem of the bed height which has the greatest influence on the quality in the use of the 3D printer, it is a method of creating the limit switch sensor and the G-code for controlling the height of the designed file. The system of claim 1, wherein the bed is not moved by the difference between the reference height and the height read by the limit switch, but the software adjusts the output height by an error so that the bed and output are spaced at an ideal distance, A method characterized by maintaining