KR101682600B1 - Apparatus and method for automatic measuring of printhead gap in 3D printer - Google Patents

Abstract

The present invention relates to an apparatus and method for automatically measuring head gaps in 3D printing, and more particularly, to a vibration sensor or a non-contact sensor in a print head or a work table, And the head gap and the horizontal error between the print head and the workbench can be automatically measured through the sensor.
To this end, the invention comprises a printhead 110 for printing a three-dimensional object; A carrier (100) for mounting and moving the printhead (110); A workbench (120) for loading printouts printed on the printhead (110); A driving unit for providing a driving force in X, Y and Z axis directions to move the carrier 100 and the work table 120 to a printing position; A sensor for generating an output signal to measure a head gap between the printhead 110 and the workbench 120; And a control unit 200 for controlling the driving unit, sensing the output signal of the sensor, and calculating a head gap and a horizontal error of the work table 120 through a corresponding calculation process.

Description

Technical Field [0001] The present invention relates to an apparatus for automatically measuring a head gap of a 3D print,

The present invention relates to an automatic head gap measuring apparatus and a method of measuring the same, and more particularly, to a head gap measuring apparatus and a method of measuring the head gap of a 3D print, The present invention relates to a 3D head gap automatic measuring apparatus and method for automatically measuring a head gap and a horizontal error between a print head and a work table through a sensor while moving the print head.

2. Description of the Related Art In recent years, the use of 3D printing capable of molding an object by using 3D data on the object has been increasing. These 3D prints have been used for pre-mass modeling and sample production. Recently, however, a technical basis has been developed that can be used in the mass production of mass-produced products centered on small-volume products of various types.

In addition, the product molding method of 3D printing includes a so-called additive type in which a target object is formed in a two-dimensional plane form, a three-dimensional laminate type in which the object is melted and adhered, and a cutting mold have.

As a kind of additive type, a wire or filament made of thermoplastic plastic is fed through a feed reel and a feed roll, and the fed filament is mounted on a three-dimensional feed mechanism that is positioned relative to the work table in three directions of X, Y and Z There is a filament melt lamination molding method in which a two-dimensional planar shape is formed and the material is laminated on a work table to form an object in three dimensions.

Such a three-dimensional printing method is referred to as an FDM (Fused Deposition Modeling) method in which a thin thermoplastic resin is melted and injected through a print head (or an extruder) and laminated one by one.

In addition, the MJM (Multi Jet Modeling) method in which a photocurable resin is melted through a print head and injected as an inkjet print, and then cured by UV light is laminated, or a method in which a scanned portion is cured by injecting laser light into a photo- SLS (Selective Laser Sintering) method using the principle of molding by using a functional polymer or a metal powder instead of a photo-curing resin in an SLA (Stereo Lithographic Apparatus) method and SLA.

One example of the FDM type 3D printing is a 3D print capable of forming a multicolor product of Korean Registered Patent No. 1346704 (registered on December 24, 2014), as shown in FIG. 1, A heater nozzle 20 mounted on the X linear movement mechanism 4 and the Y linear movement mechanism 7 and positioned in the X and Y directions and disposed in the Z direction relative to the heater nozzle 20; And a plurality of thermoplastic filaments (3) arranged on one side of the frame (1) and being in the form of a wire are respectively transported to the heater nozzle (20) The heater nozzle 20 includes a nozzle body 21 formed with a plurality of introduction holes 22 into which the plurality of filaments 3 are individually introduced, The nozzle 22 is formed with a single discharge hole through which a single passage is merged and discharged. And a controller 2 for individually controlling the position adjustment of the X, Y, Z phase of the heater nozzle 20 and the feeding operation of the plurality of filament conveying sections 31.

The heater nozzle 20 is moved by the X linear movement mechanism 4 and the Y linear movement mechanism 7 and the work table 18 is moved by the Z linear movement mechanism 14 so that the work table 18 ), And the three-dimensional molding is sequentially laminated and formed.

In addition, in the conventional 3D print, there is also a method in which the print head mounted on the carrier, that is, the heater nozzle 20 moves in the X and Z axis directions, and the work table 18 moves in the Y axis direction. Alternatively, there is a delta method in which the workbench is fixed and the print head simultaneously performs linear motion and rotational motion in the X, Y, and Z axis directions.

On the other hand, in the conventional 3D print, a head gap of 0.1 to 0.3 mm is required to be uniformly and accurately maintained over a whole plane of the workbench at regular intervals, that is, between the printhead mounted on the carrier and the workbench, This is a very important matter that the print quality is determined depending on how accurate and uniform the head gap is.

To this end, head gap measurement and correction work is conventionally performed to maintain the head gap uniformly and constantly with respect to the entire work surface plane. This allows the printhead 110 positioned above the workbench 120 to move between the printhead 110 and the workbench 120 while moving the printhead 110 to a position on the plane of the workbench 120, A gap measurement sheet 130 is inserted to measure the head gap between the print head 110 and the work table 120.

3, when the measured head cap is required to be corrected, a plurality of adjusting screws (not shown) formed between the work table 120, that is, the first work table 122 and the second work table 124 126 to adjust the height of the first work table 122 to correct the head gap between the print head 110 and the work table 120. [

The screw shaft 128 is formed on one side of the work table 120 or the second work table 124 so that the work table 120 is transferred in the Z axis, And provides a rotational force to the screw shaft 128.

However, as described above, the conventional head gap measurement operation is performed manually by the operator using the head gap measurement sheet 130 and varies depending on the state of the operator, that is, proficiency, physical condition, or emotional state, There is a problem that gap measurement is not performed.

This is because the flatness of the head gap measurement sheet 130 is irregular due to the state of the head gap measurement sheet 130, that is, the damage due to use for a long period of time, and the nature of the soft head gap measurement sheet 130 There is a problem in that the measured height of the head gap may vary depending on the position in which position is inserted.

In addition, the head gap measurement operation has a problem that accurate head gap measurement can not be performed due to a measurement error of the head gap depending on the skill of the operator.

In addition, since the printhead 110 mounted on the carrier 100 during the head gap measurement operation is in direct contact with the workbench 120 with the head gap measurement paper 130 therebetween, There is a problem that it can be damaged by the action.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vibration sensor or a non-contact sensor in a print head or a workbench and move the print head to a head gap measurement position on a plane of the workbench The present invention provides a 3D head gap automatic measuring apparatus and a measuring method thereof, which can accurately and accurately measure the head gap and the horizontal error with respect to the entire work surface plane by using a sensor and a motor.

According to another aspect of the present invention, there is provided a method of driving a three-dimensional object, including: a print head for printing a three-dimensional object; a carrier for mounting and moving the print head; And a driving unit for providing a driving force in X, Y, Z axis directions for moving the carrier and the workbench to a printing position, wherein the 3D print includes a head gap between the print head and the workbench A vibration-sensing sensor or a non-contact sensor configured between a carrier and a workbench so that measurement can be performed; And a controller for calculating a head gap and a horizontal error using a movement distance between the carrier or the print head and the work table when the vibration sensor or the non-contact sensor outputs a detection signal.

In the present invention, it is preferable that the vibration sensing type sensor is any one of an acceleration sensor, a vibration sensor and a small microphone.

In the present invention, the non-contact type sensor is preferably an optical sensor or a magnet sensor.

In the present invention, it is preferable that a plurality of head gap measurement positions are set on the work table.

In the present invention, it is preferable that the print head further includes a stopper having a lower height than the print head for measuring the head gap without contacting the work surface directly.

According to the present invention, there is provided a method of manufacturing a semiconductor device, comprising: horizontally moving a carrier or a work table to a position corresponding to a head gap measurement area in a predetermined order; Moving the carrier and the workbench in a direction perpendicular to the workbench when the horizontal movement to the measurement position is completed; Checking whether an output signal is detected by the vibration sensor or the non-contact sensor during the movement in the vertical direction; When an output signal is detected by the vibration sensor or the non-contact sensor, the vertical movement is stopped, the distance moved in the vertical direction is set as a measurement value in the measurement area, the absolute value of the head gap is calculated, Storing; Returning the carrier or workbench to its original position before moving in the vertical direction and preparing to move to the next measurement area when the storage in the controller is completed; When the movement preparation is completed, it is confirmed whether or not the head gap measurement is completed in all preset measurement areas. If not completed, the process is repeated to the initial stage and the head gap measurement is completed if the completion is completed. And a control unit.

The apparatus and method for automatically measuring a head gap of a 3D printer according to the present invention provide an effect of obtaining accurate and precise measurement values regardless of skill of an operator or a user by measuring a head gap using a sensor and a motor .

Further, the apparatus and method for measuring the head gap of a 3D printer according to the present invention provide a reduction effect on the production cost by drastically reducing the number of workings, and the effect of reducing the dissatisfaction of users.

In addition, the apparatus and method for measuring the head gap of the 3D printer according to the present invention provide the effect of completely eliminating the cause of error due to deformation or breakage of the sensor since the sensor does not directly contact the measurement object.

1 is a perspective view showing an example of a conventional 3D print.
2 is a perspective view showing a state in which a head gap is measured in a conventional 3D print.
3 is a schematic side view showing the combination of a print head and a work table in a conventional 3D print.
FIG. 4 is an enlarged view of a main portion showing a coupling relationship and an operating relationship of the head gap measuring apparatus according to the first embodiment of the present invention,
4a is a schematic view of a head gap measuring method having a vibration sensing sensor according to a first embodiment of the present invention and sensing a moment when a print head and a workbench contact each other.
4b is a schematic view of a head gap measuring method having a vibration sensing sensor according to a second embodiment of the present invention and having a carrier with a stopper and detecting the moment when the carrier contacts the workbench.
4c is a schematic view of a head gap measuring method having a non-contact type sensor according to a third embodiment of the present invention and sensing a moment when a print head and a workbench approach each other.
5 is a plan view showing a head gap measurement position of a work table according to the first embodiment of the present invention;
6 is a block diagram showing a head gap measuring method according to the first embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings (the same reference numerals are used for the same components as the conventional ones, and a detailed description thereof will be omitted).

4, the head gap measuring apparatus of the present invention includes a print head 110 for printing a three-dimensional object, a carrier 100 for mounting and moving the print head 110, A driving unit for driving the carrier 100 and the workbench 120 in the X, Y, and Z axis directions to move to a printing position; Contact type sensor 140 or the non-contact type sensor 142 for measuring the head gap between the vibration sensor 140 and the non-contact type sensor 120, and the vibration sensor 140 or the non- A control unit 200 for calculating the absolute value of the head gap (the distance between the print head and the work table) and the X axis and Y axis head gap deviation (horizontal error of the head gap) by sensing the output signal of the controller 142 ).

The driving unit may provide a driving force to move the carrier 100 or the work table 120 in the three-dimensional directions of the X, Y and Z axes so that the driving force is transmitted through the print head 110 mounted on the carrier 100, The molten liquid to be discharged is printed on the work table 120 so that a three-dimensional object is formed.

The vibration sensing sensor 140 is a means for sensing the moment when the print head 110 or the carrier 100 and the work table 120 are in contact with each other. And is configured on either side of the carrier (100) or the work table (120) or on both sides.

It is preferable that the vibration-sensing sensor 140 is constituted of any one of an acceleration sensor that is free from deformation due to repeated contact or a vibration sensor or a small microphone. Of course, the present invention is not limited thereto, and any sensor that can respond to the moment when the carrier 100 or the printhead 110 and the workbench 120 come into contact with each other can be used.

When the vibration sensing sensor 140 is applied, the print head 110 and the work table 120 may be in direct contact with each other. In order to protect the print head 110, The stopper 150 can be in contact with the work table 120 and the stopper 150 and the work table 120 can be in contact with each other.

Preferably, the stopper 150 is positioned higher than the printhead 110 to avoid collision with the output stacked on the workbench 120 by movement of the carrier 100 when printing.

The non-contact type sensor 142 is a means for sensing a moment when the print head 110 or the carrier 100 and the work table 120 approach a predetermined distance, The distance is set in advance, and the level of the output signal at the set sensing distance is set as a threshold value for sensing the sensor, which is determined by an experimental value.

The non-contact type sensor 142 may be formed of any one of an optical sensor and a magnetic sensor.

Of course, the present invention is not limited thereto, and any sensor that can output a constant output when the carrier 100 and the work table 120 are close to a certain distance can be used.

Also, it is preferable that the non-contact type sensor 142 is provided in the carrier 100 and the work table 120 is provided with a tag (not shown).

For example, it is preferable to use a reflector tag for a reflection type optical sensor and a tag including an iron component for a magnet sensor.

The head gap measurement process according to the automatic head gap measuring apparatus of the 3D printer configured as described above will be described with reference to FIG.

4A illustrates a method of using the vibration-sensitive sensor 140 and bringing the printhead 110 and the workbench 120 into direct contact with each other according to the first embodiment of the present invention. The carrier 100 is moved to the position (C1) and the Z-axis driving system is controlled to measure the head gap of the left region of the work table 120 in a state where the work table 120 is positioned on the work table 120 When the vibration-sensing sensor 140 is vertically moved until it is sensed, the worktable 120 is positioned at (B1).

The head gap at the position (C1) where the carrier 100 is the left side region of the worktable 120 becomes H (1) = M (1).

Here, M (1) is a distance at which the work table 120 moves from (B0) to (B1) at the position (C1) of the carrier 100.

The work table 120 is returned to the position B0 for the next operation and the carrier 100 is moved to position C2 to measure the head gap of the right area of the work table 120, The workbench 120 is positioned at (B2) while vertically moving the workbench 120 until the vibration-sensing sensor 140 detects it. The head gap at the position (C2) where the carrier 100 is the right side region of the work table 120 becomes H (2) = M (2).

Here, M (2) is a distance at which the work table 120 moves from (B0) to (B2) at the position (C2) of the carrier 100.

4B according to the second embodiment of the present invention is a method of using the vibration sensing sensor 140 and bringing the stopper 150 provided in the carrier 100 into contact with the work table 120, In order to measure the head gap of the left region of the work table 120 in a state where the work table 120 is located at B0, the carrier 100 is moved to position C1 and the Z axis drive system is controlled When the work table 120 is vertically moved until the vibration sensor 140 senses the work table 120, the work table 120 is positioned at (B1). The head gap at the position (C1) where the carrier 100 is the left side region of the work table 120 becomes H (1) = M (1) -d1.

Here, M (1) is the distance that the worktable 120 has moved from (B0) to (B1)

d1 is the distance between the print head 110 and the stopper 150 and is determined by the design dimension.

The work table 120 is returned to the position B0 for the next operation and the carrier 100 is moved to position C2 in order to measure the head gap of the right area of the work table 120, The workbench 120 is positioned at B2 when the workbench 120 is moved vertically until the vibration sensor 140 senses the workbench 120 by controlling the drive system. The head gap at the position (C2) where the carrier 100 is the right side region of the worktable 120 becomes H (2) = M (2) -d1.

Here, (H2) is the distance that the workbench 120 has moved from (B0) to (B2)

d1 is the distance between the print head 110 and the stopper 150 and is determined by the design dimension.

The vibration sensing sensor 140 of the first and second embodiments detects an oscillation or an impact that occurs when the print head 110 or the stopper 150 contacts the work table 120 and generates an output signal But is not limited thereto.

That is, the print head 110 or the contact sensor may detect the moment when the stopper 150 contacts the work table 120. The contact-type sensor may be composed of any one of a reed switch, a limit switch, and a pressure sensor.

In this case, it is preferable that the contact-type sensor is configured at one side of the lower end of the carrier 100. Of course, the present invention is not limited thereto, and any position can be used as long as it can output an output signal by contact with the work table 120. For example, the contact-type sensor may be configured on one side of the printhead 110.

4C is a diagram illustrating a method of using the non-contact type sensor 142 to move the carrier 100 and the work table 120 in the vicinity of each other, The carrier 100 is moved to position C1 to measure the head gap of the left region of the work table 120 and the Z axis driving system is controlled to move the work table 120 to the non- The worktable 120 is positioned at (Bl) while vertically moving until the sensor 142 detects it. The head gap at the position (C1) where the carrier 100 is the left side region of the work table 120 is H (1) = M (1) + (d2-d1).

Here, M (1) is the distance that the worktable 120 has moved from (B0) to (B1)

d1 is a distance between the print head 110 and the non-contact type sensor 142, which is determined by the design dimension,

d2 is the sensing distance of the object of the non-contact type sensor 142, and is predetermined according to the design criteria.

The work table 120 is returned to the position B0 for the next operation and the carrier 100 is moved to position C2 in order to measure the head gap of the right area of the work table 120, When the work table 120 is moved vertically by controlling the drive system until the non-contact type sensor 142 detects the work table 120, the work table 120 is positioned at (B2). The head gap at the position of the carrier C1 where the carrier 100 is the left side region of the work table 120 becomes H (2) = M (2) + (d2-d1).

Here, M (2) is the distance that the work table 120 has moved from (B0) to (B2)

d1 is the distance between the printhead 110 and the non-contact sensor 142, and is determined by the design dimension.

d2 is the sensing distance of the object of the non-contact type sensor 142, and is predetermined according to the design criteria.

In other words, the head gap in the left area of the work table 120 is H (1) and the head gap in the right area is H (2).

At this time, left and right head gap deviations (horizontal error) of the work table 120 are ΔH = H (1) -H (2).

The data H (1), H (2), and H obtained as the measurement result are utilized as information for adjusting the head gap and the horizontal of the work table 120.

In addition, the above measurement procedure is for convenience of understanding, and only the X-axis (left and right) head gap measurement process is mentioned, and the same process can be applied to the Y-axis (front and rear) head gap measurement process.

FIG. 5 is an example of setting a head gap measurement area on the work table 120 of the present invention. Referring to FIG. 4,

The head gap measurement area on the workbench 120 can be set to any area, but it is preferably set at the center and the edges A0 to A8.

In order to calculate the head gap deviation (horizontal error), the center region A0, the left regions A1, A2, and A3 of the X axis and the right regions A5, A6, and A7 and the front regions A3 and A4 of the Y axis , A5, and rear regions A1, A7, and A8.

In order to measure the deviation of the head gap with respect to the horizontal plane of the work table 120, at least three measurement areas must be set. However, in order to increase the accuracy, a plurality of locations may be set and an average value may be applied.

In addition, it is preferable to set the measurement region to be symmetric with respect to the X-axis and Y-axis with respect to the center line of the axis.

For example, as shown in Fig. 5, the A6 region is symmetric with respect to the X axis in the A2 region, and the A5, A6, and A7 regions symmetric with the average value in the A1, A2, and A3 regions are the average values.

It is possible to set an area symmetrical with respect to the Y axis in the same manner.

A head gap measuring method according to the automatic head gap measuring apparatus of the 3D print configured as described above will be described with reference to FIG.

First, the carrier or work table is horizontally moved to a position corresponding to the head gap measurement area in a predetermined order (S1).

This is horizontally moved by the driving force provided by the driving unit so that the carrier 100 or the print head 110 is positioned above the area to be measured among the measurement positions A1 to A8 set on the workbench 120. [

When the carrier or workbench is horizontally moved to the measurement position (S1), the sensor output is sensed while vertically moving in the direction in which the carrier and the workbench approach (S2).

This is because when the carrier 100 is positioned above the predetermined measurement area A0 to A8 on the workbench 120, the carrier 100 and the workbench 120 are moved vertically .

(S2) while confirming whether an output signal is sensed by a sensor formed at one side of the carrier or the work table (S3).

This continues until an output signal from the sensor is sensed.

When an output signal from the sensor is sensed (S3), the vertical movement is stopped, the vertical distance is set as a measurement value in the measurement area, and the absolute value of the head gap is calculated and stored in the controller (S4).

As a preparatory step for the next operation, the workbench is returned to the original position before approaching in the vertical direction at the vertical lower end of the carrier (S5).

If it is determined that the head gap measurement has not been completed in all of the preset measurement areas to be processed, it is determined whether the head gap measurement is completed or not. .

When the head gap measurement operation is completed for all of the preset measurement regions, the head gap absolute value and the head gap deviation in the X axis direction and the Y axis direction are calculated with reference to FIG.

The above description is only one embodiment for carrying out the head gap automatic measuring apparatus and the measuring method of the 3D print, and the present invention is not limited to the above-described embodiment. It will be understood by those skilled in the art that various changes may be made without departing from the spirit of the invention.

100: Carrier 110: Printhead
120: Work table 130: Head gap measurement paper
140: Vibration sensor 142: Non-contact sensor
150: Stopper

Claims (7)

A carriage for loading and moving the printhead, a workbench for loading printouts printed on the printhead, a carriage for loading the carriage and workbench into the print position, , And a 3D printing unit for forming a product through a driving unit that provides a driving force in the Y and Z axis directions,
A sensor configured on one side of the carrier (100) to generate an output signal to measure a head gap between the printhead (110) and the workbench (120); And
And a control unit (200) for controlling the driving unit, sensing an output signal of the sensor, and calculating a head gap according to a horizontal error of the work table (120) through an operation process of the output signal;
The carrier (100) is transported in the direction of the X axis or Y axis, which are mutually symmetrical on the work table (120);
The work table 120 is transferred in the Z axis direction of the carrier 100;
Measure the elevation height M (1) of the worktable 120 when the carrier 100 is located on one side of the worktable 120;
By measuring the elevation height M (2) of the worktable 120 by being positioned in another area on the worktable 120 in the direction in which the carrier 100 is symmetrical when the worktable 120 is in place, The head gap can be calculated according to the horizontal error between the work table 100 and the work table 120;
And the head gap is measured by the measurement unit.
The sensor according to claim 1,
A vibration sensor 140, and either a non-contact sensor 142 or a contact sensor;
And the head gap of the 3D print is automatically measured.
The method according to claim 1,
At least one stopper 150 is provided at one side of the carrier 100 to assist an output signal for measurement of a head gap in the sensor even if the print head 110 is not in contact with the work table 120 directly.
Further comprising: a head gap measuring unit for measuring the head gap of the 3D printer.
The method according to any one of claims 1 to 3,
Wherein the vibration sensor of the sensor is one of an acceleration sensor and a vibration sensor or a small microphone;
And the head gap of the 3D print is automatically measured.
The method according to any one of claims 1 to 3,
The non-contact sensor (142) of the sensor
A light sensor or a magnet sensor;
And the head gap of the 3D print is automatically measured.
The X-axis and Y-axis head gap deviation according to any one of claims 1 to 3,
The head gap of each of the representative measurement areas being symmetrical with respect to the center is set or the difference of the average value of the head gaps of the plurality of measurement areas is set;
And the head gap of the 3D printer is automatically measured.
A head gap measuring method of 3D printing,
(S1) of horizontally moving the carrier to a corresponding position in the head gap measuring area in a predetermined order on the work table;
A step (S2) of vertically moving the work table in the Z-axis direction of the carrier when the carrier is horizontally moved to the corresponding position;
(S3) confirming whether an output signal is sensed by any one of a vibration sensor, a non-contact sensor, and a touch sensor formed on one side of the carrier in a vertical direction of the work table;
When the output signal of the sensor is sensed, the vertical movement of the work table in the Z-axis direction is stopped, the distance moved in the vertical direction is set as a head gap measurement value in the measurement region, (S4);
(S5) when the control unit has completed the storing, returning the work table to the home position and preparing the carrier to move to another measurement area located in a symmetrical direction of the measurement area;
When the preparation for movement is completed, it is confirmed whether or not the measurement for all of the set measurement areas is completed. If not completed, the carrier moves to another measurement area on the work table to repeat steps S1 to S5, (S6); And
Calculating a head gap deviation (horizontal error) with respect to the X axis or Y axis (S7) when the head gap measurement of each measurement area is completed;
Wherein the head gap of the 3D printer is measured.

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