Non-contact printing head height calibration device, method and equipment

Abstract

The invention relates to the technical field of printing head calibration, and discloses a non-contact printing head height calibration device, method and equipment, and the device comprises a projection measurement module which comprises a calibration reference block, a parallel light transmitter and a parallel light receiver, position information of the calibration reference block and the discharging end of the printing head in the parallel light is determined according to the shielding information of the parallel light; the calibration module is used for measuring the height value of the calibration reference block as the calibration height; and the controller is used for acquiring the cut-off height and determining the distance between the printing head discharging end and the printing head mounting end according to the position information of the printing head discharging end and the calibration reference block in the parallel light, the cut-off height and the calibration height. The calibration reference block and the printing head are used for shielding the parallel light, the height difference is determined according to the shielding information of the parallel light, the height of the printing head is calibrated in combination with the calibration height, mechanical contact does not exist, the situation that the printing head is damaged due to mechanical contact is reduced, the maintenance cost is reduced, and the calibration efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of print head calibration, and in particular to a non-contact print head height calibration device, method and equipment. Background Art

[0002] In scenarios such as 3D printing, dispensing or machining, tiny working heads such as print heads, dispensing heads, and tiny cutting heads are often used. The service life of tiny working heads is very short and needs to be replaced frequently. After each replacement of the working head, the initial position of the working head needs to be calibrated in space. The common working head calibration method is mainly contact calibration, that is, the working head is continuously moved until it touches a certain surface and generates a certain force. The sensor of the contact surface is triggered by the working head, generating a feedback signal, causing the working head to stop moving, and obtaining the position information of the print head based on the distance moved by the working head during the trigger reading and the position of the contacted surface. Although the contact method can be accurately calibrated and the process is relatively simple, it has certain requirements for the hardness and strength of the working head. For tiny and fragile precision print heads, the contact calibration method is easy to damage the print head or cause certain damage during calibration: the print head moves to the surface to be contacted, and a force has been generated, but the sensor trigger threshold has not been reached. The print head continues to move. Before the sensor trigger threshold, the interaction force exceeds the tolerance range of the print head, causing the print head to be damaged. Summary of the invention

[0003] In view of this, the present invention provides a non-contact print head height calibration device, method and equipment to solve the problem that the precision print head is easily damaged during the contact calibration process.

[0004] In a first aspect, the present invention provides a non-contact print head height calibration device, the device comprising: a projection measurement module, a calibration module, and a controller, wherein:

[0005] The projection measurement module includes a calibration reference block, a parallel light transmitter, and a parallel light receiver. The parallel light transmitter and the parallel light receiver are placed in parallel with each other at a preset distance. The parallel light transmitter is used to transmit parallel light, and the parallel light receiver is used to receive parallel light. The parallel light is blocked by the calibration reference block and the discharge end of the print head. The position information of the calibration reference block and the discharge end of the print head in the parallel light is determined according to the information that the parallel light is blocked.

[0006] A calibration module, used for measuring a height value of a calibration reference block as a calibration height;

[0007] The controller is used to obtain the cut-off height, determine the distance between the print head discharge end and the print head mounting end according to the position information of the print head discharge end and the calibration reference block in the parallel light, the cut-off height, and the calibration height, and realize the calibration of the print head height. The cut-off height is the height value of the print head mounting end when the print head discharge end enters the parallel light range and blocks the parallel light.

[0008] The non-contact print head height calibration device provided by the present invention utilizes a calibration reference block and a print head to block parallel light, determines position information of the calibration reference block and a discharge end of the print head according to information on the blocking of the parallel light, and realizes calibration of the print head height in combination with the calibration height, without the need for the print head to contact the calibration reference block, thereby reducing damage to the print head caused by mechanical contact, reducing maintenance costs, and improving calibration efficiency.

[0009] In an optional embodiment, the controller is further used to control the movement of the projection measurement module and / or the calibration module, and adjust the relative positions of the two in the horizontal plane so that the calibration reference block is within the measurement range of the calibration module.

[0010] The non-contact print head height calibration device provided by the present invention moves the projection measurement module and / or the calibration module in a horizontal plane, and the relative position adjustment method is more flexible, which can meet the needs of different scenarios.

[0011] In an optional embodiment, the projection measurement module further includes: a fixing bracket for fixing the calibration reference block, the parallel light transmitter, and the parallel light receiver at respective preset positions.

[0012] The calibration reference block includes a calibration table and a calibration block bracket, wherein:

[0013] Calibration table, used to block parallel light;

[0014] Calibration block bracket, used to support the calibration table.

[0015] In the non-contact print head height calibration device provided by the present invention, the position of the projection measurement module is relatively fixed, thereby ensuring the effectiveness and accuracy of the print head height calibration, avoiding damage to the print head or other equipment due to the movement of the projection measurement module, and improving the safety of the print head height calibration process.

[0016] In an optional embodiment, the calibration module includes:

[0017] The height sensor is used to measure the height value of the calibration reference block as the calibration height.

[0018] The non-contact print head height calibration device provided by the present invention uses a height measuring sensor to measure the height of a calibration reference block. The measurement method is simple and the measurement result is accurate. When measuring the height of the calibration table, there is no need to contact the calibration table, thereby avoiding equipment damage caused by mechanical contact and reducing maintenance costs.

[0019] In a second aspect, the present invention provides a non-contact print head height calibration method, the method is applied to any non-contact print head height calibration device in the first aspect, the method comprising:

[0020] Obtain the cut-off height of the print head and the information that the parallel light of the print head installation end is blocked by the print head discharge end and the calibration reference block when the print head installation end is at the cut-off height. The cut-off height is the height value of the print head installation end when the print head discharge end enters the parallel light range and blocks the parallel light.

[0021] Determine the position information of the material discharge end of the print head and the position information of the calibration reference block according to the blocked information;

[0022] Determine the height difference between the print head discharge end and the upper surface of the calibration reference block according to the position information of the print head discharge end and the position information of the calibration reference block;

[0023] The calibration height is obtained, and the distance between the discharge end of the print head and the installation end of the print head is determined according to the height difference, the cut-off height, and the calibration height, so as to calibrate the print head height.

[0024] The non-contact print head height calibration method provided by the present invention utilizes a calibration reference block and a print head to block parallel light, determines position information of the calibration reference block and a discharge end of the print head according to information on the blocking of the parallel light, and realizes calibration of the print head height in combination with the calibration height, without the need for the print head to contact the calibration reference block, thereby reducing damage to the print head caused by mechanical contact, reducing maintenance costs, and improving calibration efficiency.

[0025] In an optional embodiment, the method further includes:

[0026] Control the print head to descend from an initial height to a safe height at a first preset speed, the initial height being a height value of the print head mounting end when the print head is located at a preset starting position, and the safe height being a height value of the print head mounting end when the height difference between the print head discharge end and the upper surface of the calibration reference block is greater than a preset threshold;

[0027] The print head is controlled to descend from the safety height to the cut-off height at a second preset speed, where the second preset speed is less than the first preset speed.

[0028] The non-contact print head height calibration method provided by the present invention controls the print head to descend at two different speeds during the height calibration process, thereby ensuring the calibration speed and avoiding safety problems caused by the print head descending too fast, thereby improving safety.

[0029] In an optional implementation, obtaining the calibration height includes:

[0030] Moving the calibration module and / or the calibration reference block in a horizontal plane so that the calibration reference block is within the measurement range of the calibration module;

[0031] The calibration module is used to measure the height value of the calibration reference block as the calibration height.

[0032] The non-contact print head height calibration method provided by the present invention determines the height of the calibration reference block as the calibration height in a non-contact manner, the calibration height is more accurate, and the method of moving the calibration module and the calibration module is more flexible, which can meet the needs of different scenarios.

[0033] In an optional embodiment, the print head includes print heads of multiple different lengths, and when the print head with the longest length reaches a safe height, the height difference between the discharge end of the print head and the upper surface of the calibration reference block is greater than 0.

[0034] The non-contact print head height calibration method provided by the present invention is applicable to print heads of various lengths and has a wider application range. When the print head with the longest length is in a safe position, it will not contact the calibration reference block, thus avoiding collision damage and improving the safety of print head height calibration.

[0035] In a third aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the method of the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0036] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to cause a computer to execute the method of the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 is a structural schematic diagram of a non-contact print head height calibration device according to an embodiment of the present invention;

[0039] Figure 2is a structural schematic diagram of another non-contact print head height calibration device according to an embodiment of the present invention;

[0040] Figure 3 is a schematic flow chart of a non-contact print head height calibration method according to an embodiment of the present invention;

[0041] Figure 4 is a schematic diagram of print heads of different lengths in a non-contact print head height calibration method according to an embodiment of the present invention;

[0042] Figure 5 is a schematic diagram of measuring the calibration height in the non-contact print head height calibration method according to an embodiment of the present invention;

[0043] Figure 6 is a schematic diagram of a print head descending from an initial height to a safe height in a non-contact print head height calibration method according to an embodiment of the present invention;

[0044] Figure 7 is a schematic diagram of a print head entering a parallel light projection field of view in a non-contact print head height calibration method according to an embodiment of the present invention;

[0045] Figure 8 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0047] The embodiments of the present invention provide a non-contact print head height calibration device, method and equipment, which blocks parallel light through a calibration reference block and a print head, and calibrates the print head height according to the parallel light blocking information and the calibration height, so as to achieve the effect of realizing print head height calibration through a non-contact method.

[0048] According to an embodiment of the present invention, a non-contact print head height calibration device is provided. Figure 1 As shown, the device includes: a projection measurement module 1, a calibration module 2, and a controller 3.

[0049] like Figure 1As shown, the projection measurement module 1 includes a calibration reference block 11, a parallel light transmitter 12, and a parallel light receiver 13. The parallel light transmitter 12 and the parallel light receiver 13 are placed in parallel with a preset distance. The parallel light transmitter 12 is used to transmit parallel light, and the parallel light receiver 13 is used to receive parallel light. The parallel light is blocked by the calibration reference block 11 and the print head discharge end, and the position information of the calibration reference block 11 and the print head discharge end in the parallel light is determined according to the information that the parallel light is blocked.

[0050] Specifically, the projection measurement module 1 can be fixed at a preset position within the printing plane of the 3D printer, but the projection measurement module 1 cannot be in the printing area and cannot affect normal printing. When the print head needs to be calibrated, the projection measurement module 1 can be manually placed at a preset position within the printing plane of the 3D printer, but during the entire calibration process, the position of the projection measurement module 1 remains fixed.

[0051] The parallel light emitter 12 in the projection measurement module 1 can emit parallel light of a preset area, and the parallel light receiver 13 can correspondingly receive parallel light of a preset area, and the two are placed in parallel at a preset distance. When an object (whose material is a material that parallel light cannot penetrate) enters the parallel light, the parallel light is blocked, and the parallel light receiver 13 cannot receive the parallel light of the entire area emitted by the parallel light emitter 12, so the contour projection of the object under the parallel light can be determined, and the blocked area of ​​the parallel light can be determined based on the contour projection, and then the size of the object can be determined. There is an optimal measurement range between the parallel light emitter 12 and the parallel light receiver 13. During the calibration process, the blocking object (for example: the calibration reference block 11) can be placed within the optimal measurement range to ensure the accuracy of the print head calibration. The optimal measurement range can be the middle position between the parallel light emitter 12 and the parallel light receiver 13 and the middle position of the parallel light, which is only used as an example, but is not limited to this.

[0052] like Figure 1 As shown, the calibration module 2 is used to measure the height value of the calibration reference block 11 as the calibration height.

[0053] Specifically, the calibration module 2 can be fixedly installed at the print head installation position in the 3D printing device, located above the projection calibration module 2. The position can be adjusted so that the calibration module 2 is located directly above the calibration reference block 11, so that the calibration reference block 11 is within the measurement range of the calibration module 2, and the height value of the calibration reference block 11 is measured as the calibration height.

[0054] like Figure 1As shown, the controller 3 is used to obtain the cut-off height, and determine the distance between the print head discharge end and the print head mounting end according to the position information of the print head discharge end and the calibration reference block 11 in the parallel light, the cut-off height, and the calibration height, so as to calibrate the print head height. The cut-off height is the height value of the print head mounting end when the print head discharge end enters the parallel light range and blocks the parallel light.

[0055] Specifically, the controller 3 is respectively communicated with the projection measurement module 1, the calibration module 2 and the 3D printer to be calibrated to obtain relevant data of the projection measurement module 1, the calibration module 2 and the 3D printer to be calibrated, including: the end height when the print head of the 3D printer to be calibrated moves to the calibration position, the information of the print head discharge end and the calibration reference block 11 in the parallel light, and the calibration height measured by the calibration module 2.

[0056] The controller 3 uses the obtained data to perform calculations and processing to obtain the distance between the discharge end of the print head and the installation end of the print head, and transmits the distance as the print head length to the 3D printer to be calibrated, thereby realizing the calibration of the print head height.

[0057] The non-contact print head height calibration device provided in this embodiment utilizes the calibration reference block 11 and the print head to block parallel light, determines the position information of the calibration reference block 11 and the print head discharge end according to the information of the parallel light being blocked, and realizes the calibration of the print head height in combination with the calibration height. There is no need for the print head to contact the calibration reference block 11, thereby reducing damage to the print head caused by mechanical contact, reducing maintenance costs, and improving calibration efficiency.

[0058] In some optional embodiments, the controller 3 is further used to control the movement of the projection measurement module 1 and / or the calibration module 2 , and adjust the relative positions of the two in the horizontal plane so that the calibration reference block 11 is within the measurement range of the calibration module 2 .

[0059] Specifically, a 3D printer usually needs to set a printing coordinate system, and uses the printing coordinate system to accurately determine the printing position. Taking the xy axis of the printing coordinate system of the 3D printer as the horizontal plane, the calibration module 2 and the projection measurement module 1 can be relatively moved in the xy axis direction of the horizontal plane to adjust the relative positions of the two in the horizontal plane. The calibration reference block 11 is within the measurement range of the calibration module 2. Generally, the measurement range of the calibration module 2 is within a preset range directly below the calibration module 2. This is only an example, but is not limited to this.

[0060] At least one of the calibration module 2 and the projection measurement module 1 is fixed on an axis that can move in the xy direction, or the calibration module 2 can move in the x direction and the projection measurement module 1 can move in the y direction, or the calibration module 2 can move in the y direction and the projection measurement module 1 can move in the x direction. In practical applications, the calibration module 2 can be installed on the print head installation axis of the 3D printing device without setting a separate moving axis. The print head installation axis used by the calibration module 2 and the print head installation axis to be calibrated can be different axes or the same axis, which is only used as an example, but not limited to this.

[0061] The non-contact print head height calibration device provided in this embodiment moves the projection measurement module 1 and / or the calibration module 2 in a horizontal plane, and the relative position adjustment method is more flexible, which can meet the needs of different scenarios.

[0062] In some optional embodiments, such as Figure 2 As shown, the projection measurement module 1 further includes: a fixing bracket 14, which is used to fix the calibration reference block 11, the parallel light transmitter 12, and the parallel light receiver 13 at respective preset positions; the calibration reference block 11 includes a calibration table and a calibration block bracket; the calibration table is used to block the parallel light; and the calibration block bracket is used to support the calibration table.

[0063] Specifically, the parallel light transmitter 12 and the parallel light receiver 13 are fixed in parallel at two ends of the fixing bracket 14, and the calibration reference block 11 is fixed in the middle of the fixing bracket 14. Part or all of the calibration table enters the parallel light range.

[0064] In the non-contact print head height calibration device provided in this embodiment, the position of the projection measurement module 1 is relatively fixed, thereby ensuring the effectiveness and accuracy of the print head height calibration, avoiding damage to the print head or other equipment due to the movement of the projection measurement module 1, and improving the safety of the print head height calibration process.

[0065] In some optional embodiments, such as Figure 2 As shown, the calibration module 2 includes:

[0066] The height sensor is used to measure the height value of the calibration reference block 11 as the calibration height.

[0067] Specifically, the height measuring sensor can be a laser ranging sensor or an ultrasonic ranging sensor. The first distance from the height measuring sensor to the horizontal plane where the projection measurement module 1 is located can be measured, and then the second distance from the height measuring sensor to the upper surface of the reference calibration block can be measured. The difference between the first distance and the second distance is used as the height of the calibration reference block 11, that is, the calibration height. This is only an example, but not limited to this.

[0068] The non-contact print head height calibration device provided in this embodiment uses a height measuring sensor to measure the height of the calibration reference block 11. The measurement method is simple and the measurement result is accurate. There is no need to contact the calibration table when measuring the height of the calibration table, thereby avoiding equipment damage caused by mechanical contact and reducing maintenance costs.

[0069] According to the present invention, an embodiment of a non-contact print head height calibration method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0070] In this embodiment, a non-contact print head height calibration method is provided, which can be used in the above-mentioned computer system or non-contact print head height calibration device. Figure 3 is a flow chart of a non-contact print head height calibration method according to an embodiment of the present invention. Figure 3 As shown, the process includes the following steps:

[0071] Step S101, obtaining the cut-off height of the print head and the obstruction information of the parallel light being blocked by the print head discharge end and the calibration reference block 11 when the print head installation end is at the cut-off height. The cut-off height is the height value of the print head installation end when the print head discharge end enters the parallel light range and blocks the parallel light.

[0072] Specifically, when the discharge end of the print head enters the parallel light range and blocks the parallel light, the height value of the print head installation end is obtained as the cut-off height H2. The information that the parallel light is blocked by the discharge end of the print head and the calibration reference block 11 when the print head installation end is at the cut-off height is obtained. To ensure the measurement accuracy, the length of the parallel light blocked by the discharge end of the print head can be one-third to one-half of the field of view of the parallel light, which is only used as an example, but is not limited thereto.

[0073] Step S102, determining the position information of the discharge end of the print head and the position information of the calibration reference block 11 according to the blocked information.

[0074] Specifically, the print head and the calibration reference block 11 block the parallel light at the same time. According to the information of the blocked parallel light, the position information of the print head discharge end and the position information of the calibration block reference block can be determined. For example: based on the printing horizontal plane, the height range of the parallel light is 1mm~10mm. After being blocked, the area of ​​the parallel light blocked by the print head is 3.5mm in the vertical direction, and the area of ​​the parallel light blocked by the calibration reference block 11 is 3mm in the vertical direction. It can be determined that the height of the print head discharge end from the projection measurement module reference plane is 6.5mm, and the height difference between the upper surface of the calibration reference block 11 and the projection measurement module reference plane is 4mm. This is only an example, but not limited to this.

[0075] Step S103 , determining the height difference between the discharge end of the print head and the upper surface of the calibration reference block 11 according to the position information of the discharge end of the print head and the position information of the calibration reference block 11 .

[0076] Specifically, the position information of the discharge end of the print head and the position information of the calibration reference block 11 are both determined based on the blocked information of the parallel light, so the height difference between the discharge end of the print head and the upper surface of the calibration reference block 11 can be calculated according to the projection information of the discharge end of the print head and the calibration reference block 11 in the parallel light. For example, in step S102, since the print head blocks the parallel light from the upper line of the range of the parallel light, and the calibration reference block 11 blocks the parallel light from the lower line of the range of the parallel light, the length of the area of ​​the parallel light blocked by the print head in the vertical direction is 3.5 mm, and the length of the area of ​​the parallel light blocked by the calibration reference block 11 in the vertical direction is 3.0 mm, it can be determined that the height difference s between the discharge end of the print head and the upper surface of the calibration reference block 11 is 9.0 mm-3.5 mm-3.0 mm=2.5 mm, which is only used as an example, but is not limited to this.

[0077] Step S104, obtaining the calibration height, and determining the distance between the discharge end of the print head and the installation end of the print head according to the height difference, the cut-off height, and the calibration height, so as to calibrate the print head height.

[0078] Specifically, the height value of the calibration reference block 11 is obtained through the height sensor as the calibration height h, and the distance between the print head discharge end and the print head installation end is determined according to the height difference s, the end height H2 and the calibration height h, as the 0-position height of the print head based on the height of the height sensor of the calibration module 2, and the 0-position height = end height H2-height difference s-calibration height h.

[0079] It should be noted that all height values ​​in this embodiment are based on the measurement of the height sensor. The height sensor of the calibration module is the same as the height sensor during actual printing to ensure the same reference height. For the print head, the 0-bit height means: when the height sensor measures the surface of an object as 0 (the reading of the surface of the object inside the 3D printer is 0), the height position of the print head mounting end when the corresponding print head discharge end contacts the surface of the object. After obtaining the 0-bit height, before the actual sample is printed, it is necessary to first use the height sensor to measure the height of the surface of the sample to be printed, and obtain the height position difference between the surface of the sample to be printed and the 0-bit height position according to the measurement value of the height sensor. Further, by controlling the height of the print head mounting end, it is possible to accurately control the print head discharge end to drop to a preset height position from the surface of the object to be printed. For example, during actual printing, when the height sensor measures the surface of the sample to be printed as 0, the corresponding 0-bit height of the print head, that is, the height at which the print head discharge end just contacts the surface, assuming that the mechanical height of the print head mounting end corresponding to the 0-bit height is 50mm.

[0080] When the height sensor tests the sample to be printed and the measured value is 0.1mm, the print head needs to be 0.1mm higher than its 0 position, and the test print head just touches the surface of the sample to be printed. The corresponding mechanical height of the installation end is 50.1mm. When the height sensor tests the sample to be printed and the measured value is -0.5mm, the print head needs to be 0.5mm lower than its 0 position height, and the test print head discharge end just touches the surface of the sample to be printed. The corresponding mechanical height of the installation end is 49.5mm. This is just an example, but not limited to this. It should be noted that the positive and negative correspond to lifting or falling here, which can be customized at the software level.

[0081] This embodiment implements height calibration, which can be understood as calibration in the z direction. The calibration in the x direction and the y direction can adopt the existing calibration method for the print head in the x and y directions, and the specific implementation method is not limited.

[0082] The non-contact print head height calibration method provided in this embodiment utilizes the calibration reference block 11 and the print head to block parallel light, determines the position information of the calibration reference block 11 and the print head discharge end according to the information of the parallel light being blocked, and realizes the calibration of the print head height in combination with the calibration height. There is no need for the print head to contact the calibration reference block 11, thereby reducing damage to the print head caused by mechanical contact, reducing maintenance costs, and improving calibration efficiency.

[0083] In some optional embodiments, the method further comprises:

[0084] The print head is controlled to descend from an initial height to a safe height at a first preset speed. The initial height is the height value of the print head mounting end when the print head is located at a preset starting position. The safety height is the height value of the print head mounting end when the height difference between the print head discharge end and the upper surface of the calibration reference block 11 is greater than a preset threshold.

[0085] The print head is controlled to descend from the safety height to the cut-off height at a second preset speed, where the second preset speed is less than the first preset speed.

[0086] Specifically, based on actual conditions, the initial position of the print head is usually directly above the printing area, so during calibration, the print head needs to drop from the initial height H0 to the end height. To avoid collision, a safety height H1 between the initial height H0 and the end height H2 can be manually picked up or set. The specific vertical height of the safety height can be determined according to actual conditions. It is necessary to ensure that when the print head is at the safety height, the print head discharge end has entered the parallel light range, and the print head discharge end does not collide with the calibration reference block 11. The preset threshold is set according to actual conditions. For example, it can be set to the distance between the upper surface of the calibration reference block 11 and the upper line of the parallel light range. This is only an example, but is not limited to this.

[0087] To reduce the calibration time, the print head is controlled to drop from the initial height H0 to the safety height H1 at a faster speed. Then, to ensure safety, the print head is controlled to drop from the safety height H1 to H2 at a slower speed. In case of a print head trajectory error, the print head can be manually controlled to stop urgently to avoid damage to the print head.

[0088] The non-contact print head height calibration method provided in this embodiment controls the print head to descend at two different speeds during the height calibration process, thereby ensuring the calibration speed while avoiding safety problems caused by the print head descending too fast, thereby improving safety.

[0089] In some optional implementations, obtaining the calibration height includes:

[0090] Step a1: move the calibration module 2 and / or the calibration reference block 11 in a horizontal plane so that the calibration reference block 11 is located within the measurement range of the calibration module 2 .

[0091] Step a2: using the calibration module 2 to measure the height value of the calibration reference block 11 as the calibration height.

[0092] Specifically, a 3D printer usually needs to set a printing coordinate system, and uses the printing coordinate system to accurately determine the printing position. Taking the xy axis of the printing coordinate system of the 3D printer as the horizontal plane, the calibration module 2 and the projection measurement module 1 can be relatively moved in the xy axis direction of the horizontal plane to adjust the relative positions of the two in the horizontal plane. The calibration reference block 11 is within the measurement range of the calibration module 2. Generally, the measurement range of the calibration module 2 is within a preset range directly below the calibration module 2. This is only an example, but is not limited to this.

[0093] At least one of the calibration module 2 and the projection measurement module 1 is fixed on an axis that can move in the xy direction, or the calibration module 2 can move in the x direction and the projection measurement module 1 can move in the y direction, or the calibration module 2 can move in the y direction and the projection measurement module 1 can move in the x direction. In practical applications, the calibration module 2 can be installed on the print head installation axis of the 3D printing device without setting a separate moving axis. The print head installation axis used by the calibration module 2 and the print head installation axis to be calibrated can be different axes or the same axis, which is only used as an example, but not limited to this.

[0094] The non-contact print head height calibration method provided in this embodiment determines the height of the calibration reference block 11 as the calibration height in a non-contact manner. The calibration height is more accurate, and the method of moving the calibration module 2 and the calibration module is more flexible, which can meet the needs of different scenarios.

[0095] In some optional embodiments, the print head includes print heads of multiple different lengths, and when the print head with the longest length reaches a safe height, the height difference between the discharge end of the print head and the upper surface of the calibration reference block 11 is greater than 0.

[0096] Specifically, Figure 4 As shown, the length of the first precision print head on the left is less than the length of the second precision print head on the right. In actual calibration, if the printer can use these two print heads, when setting the safety height during calibration, it is necessary to ensure that when the installation end of the second precision print head is at the safety height, its discharge end does not touch the upper surface of the calibration reference block 11.

[0097] The non-contact print head height calibration method provided in this embodiment is applicable to print heads of various lengths and has a wider range of applications. When the longest print head is in a safe position, it will not contact the calibration reference block 11, avoiding collision damage and improving the safety of print head height calibration.

[0098] In a specific implementation, after the printer replaces the print head, the process of height calibration of the target print head is as follows:

[0099] (1) Move the height sensor and / or projection measurement module 1 in the x and y directions so that the height sensor measures the height value of the calibration reference block 11 as the calibration height h, such as Figure 5 shown.

[0100] (2) Move the target print head in the x and y directions to a preset area above the reference calibration block. The target print head does not need to be completely aligned with the center of the calibration reference block 11. Figure 6 shown.

[0101] (3) The target print head is rapidly lowered from the initial height H0 to the safe height H1, and the print head is slowly moved into the parallel light field of view. The height of the print head installation end at this time is recorded as the cut-off height H2, and the projection measurement sensor is used to determine the projection distance s (i.e., height difference s) between the upper surface of the calibration reference block 11 and the discharge end of the print head, as shown in Figure 7 shown.

[0102] (4) Calculate the 0-bit height of the print head based on the height of the height sensor of the calibration module 2: 0-bit height = end height H2 - projection distance s - calibration height h.

[0103] (5) Raise the print head to the initial height to complete the calibration of the target print head height.

[0104] The embodiment of the present invention also provides a computer device having the above Figure 1 or Figure 2 The non-contact print head height calibration device shown.

[0105] See also Figure 8 , Figure 8 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Figure 8 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 8 A processor 10 is taken as an example.

[0106] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0107] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0108] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0109] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0110] The computer device further comprises a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0111] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0112] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A non-contact print head height calibration device, characterized in that: The device comprises: a projection measurement module, a calibration module, and a controller, wherein: A projection measurement module, comprising a calibration reference block, a parallel light transmitter, and a parallel light receiver, wherein the parallel light transmitter and the parallel light receiver are placed in parallel with each other at a preset distance, the parallel light transmitter is used to transmit parallel light, and the parallel light receiver is used to receive parallel light, the parallel light is blocked by the calibration reference block and the print head discharge end, and the position information of the calibration reference block and the print head discharge end in the parallel light is determined according to the information that the parallel light is blocked; A calibration module, used for measuring the height value of the calibration reference block as a calibration height; The controller is used to obtain the cut-off height, determine the distance between the print head discharge end and the print head mounting end according to the position information of the print head discharge end and the calibration reference block in the parallel light, the cut-off height, and the calibration height, and realize the calibration of the print head height. The cut-off height is the height value of the print head mounting end when the print head discharge end enters the parallel light range and blocks the parallel light.

2. The non-contact print head height calibration device according to claim 1, characterized in that: The controller is further used to control the movement of the projection measurement module and / or the calibration module, and adjust the relative positions of the two in the horizontal plane so that the calibration reference block is within the measurement range of the calibration module.

3. The non-contact print head height calibration device according to claim 1, characterized in that: The projection measurement module further includes: a fixing bracket for fixing the calibration reference block, the parallel light transmitter, and the parallel light receiver at respective preset positions. The calibration reference block includes a calibration table and a calibration block bracket, wherein: Calibration table, used to block parallel light; The calibration block bracket is used to support the calibration table.

4. The non-contact print head height calibration device according to claim 3, characterized in that: The calibration module comprises: The height sensor is used to measure the height value of the calibration reference block as the calibration height.

5. A non-contact print head height calibration method, characterized in that: The method is applied to the non-contact print head height calibration device according to any one of claims 1 to 4, and the method comprises: Obtaining the cut-off height of the print head and the obstruction information of the parallel light of the print head mounting end being blocked by the print head discharge end and the calibration reference block when the print head mounting end is at the cut-off height, wherein the cut-off height is the height value of the print head mounting end when the print head discharge end enters the parallel light range and blocks the parallel light; Determine the position information of the material discharge end of the print head and the position information of the calibration reference block according to the blocked information; Determining a height difference between the print head discharge end and the upper surface of the calibration reference block according to the position information of the print head discharge end and the position information of the calibration reference block; The calibration height is obtained, and the distance between the discharge end of the print head and the installation end of the print head is determined according to the height difference, the cut-off height, and the calibration height, so as to calibrate the print head height.

6. The non-contact print head height calibration method according to claim 5, characterized in that: The method further comprises: Controlling the print head to descend from an initial height to a safe height at a first preset speed, wherein the initial height is a height value of the print head mounting end when the print head is located at a preset starting position, and the safe height is a height value of the print head mounting end when the height difference between the print head discharge end and the upper surface of the calibration reference block is greater than a preset threshold; The print head is controlled to descend from the safety height to the cut-off height at a second preset speed, wherein the second preset speed is less than the first preset speed.

7. The non-contact print head height calibration method according to claim 5, characterized in that: The obtaining of the calibration height comprises: Moving the calibration module and / or the calibration reference block in a horizontal plane so that the calibration reference block is located within the measurement range of the calibration module; The calibration module is used to measure the height value of the calibration reference block as the calibration height.

8. The non-contact print head height calibration method according to claim 6, characterized in that: The print head includes print heads of various lengths, and when the print head with the longest length reaches a safe height, the height difference between the discharge end of the print head and the upper surface of the calibration reference block is greater than 0.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method according to any one of claims 5 to 8 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method according to any one of claims 5 to 8.

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