CN109089383B

CN109089383B - Liquid metal printer and welding mechanism thereof

Info

Publication number: CN109089383B
Application number: CN201811109597.8A
Authority: CN
Inventors: 严启臻
Original assignee: Beijing Dream Ink Technology Co Ltd
Current assignee: Beijing Dream Ink Technology Co Ltd
Priority date: 2018-09-21
Filing date: 2018-09-21
Publication date: 2023-12-26
Anticipated expiration: 2038-09-21
Also published as: CN109089383A

Abstract

The invention discloses a liquid metal printer and a welding mechanism thereof, wherein the welding mechanism comprises: an extrusion mechanism moving in a vertical direction for extruding a unit mass of solder onto a surface of a substrate located directly therebelow; wherein the solder is a viscous metal mixture at normal temperature; and the molding pen moves along the vertical direction and the horizontal direction and is used for pushing the solder extruded on the surface of the substrate and enabling the solder to wrap the connection point between the pin of the patch element and the liquid metal circuit on the surface of the substrate in a certain shape. According to the invention, the conductive paste which is sticky at normal temperature is used as the solder, and the solder is used for plugging the connection part of the liquid metal circuit and the element pin, so that the conductive paste can be used as a conductive connecting agent for auxiliary connection of the liquid metal circuit and the element pin, and the problem of physical separation caused by penetration of colloid into the connection part in the subsequent sealing process can be avoided.

Description

Liquid metal printer and welding mechanism thereof

Technical Field

The invention belongs to the technical field of liquid metal printing, and particularly relates to a liquid metal printer and a welding mechanism thereof.

Background

The soldering of the patch element is a necessary link in the preparation process of the patch electronic circuit, the solder is heated to be in a molten state, the patch element and the printed circuit are bonded by the solder in the molten state, and after the solder is cooled and fixed, the joint between the patch element and the printed circuit can be stably connected, and the main soldering modes include spot welding, reflow soldering and the like.

With the demand for flexible printed circuits and the continuous improvement of the demand for the flexible printed circuits, the liquid metal printed circuits are generated, the printed circuits in the liquid metal printed circuits are formed by low-melting-point metals which are liquid at normal temperature, the patch elements are adhered on the base material through glue, pins of the patch elements are in contact connection with corresponding liquid metal circuits, but due to the fact that the size of the patch elements is too small, the quantity of the points at the center of the bottom surface of the patch elements is small due to the fact that the size of the patch elements is too small, the quantity of the points can only provide certain bonding strength in a certain time, stable connection between the liquid metal circuits and the pins of the patch elements is not realized, and when colloid encapsulation is carried out, encapsulation glue easily permeates between the liquid metal circuits and the pins of the patch elements, so that the liquid metal circuits are separated from the pins of the patch elements, and even the patch elements are propped open.

The liquid metal printed circuit is not suitable for a heating welding mode in the prior art, the deformation of the liquid metal printed circuit is easily caused by heating, the surface of the printed substrate is denatured mainly due to the inadequacy of the temperature of the printed substrate, the liquid metal is not easily attached, the liquid metal is deformed in a shrinking way, and a device for stably connecting the liquid metal printed circuit with the pins of the patch element is absent in the prior art.

Disclosure of Invention

Therefore, an objective of the present invention is to provide a soldering mechanism to solve the problem of separation of the liquid metal circuit and the component pins caused by the unstable connection structure of the liquid metal circuit and the component pins and easy penetration of the encapsulation glue into the connection parts in the prior art.

In some illustrative embodiments, the welding mechanism includes: an extrusion mechanism moving in a vertical direction for extruding a unit mass of solder onto a surface of a substrate located directly therebelow; wherein the solder is a viscous metal mixture at normal temperature; and the molding pen moves along the vertical direction and the horizontal direction and is used for pushing the solder extruded on the surface of the substrate and enabling the solder to wrap the connection point between the pin of the patch element and the liquid metal circuit on the surface of the substrate in a certain shape.

In some alternative embodiments, the welding mechanism further comprises: a horizontal moving mechanism, a first lifting mechanism and a second lifting mechanism which are arranged on the horizontal moving mechanism; the extrusion molding mechanism is arranged on the first lifting mechanism, and is driven to move along the vertical direction by the first lifting mechanism; the molding pen is arranged on the second lifting mechanism, is driven to move in the vertical direction by the second lifting mechanism, and is driven to move in the horizontal direction by the horizontal moving mechanism.

In some alternative embodiments, the extrusion mechanism comprises: the bottom of the tube body is of a conical mouth structure converging the solder; the top end of the vertically arranged discharging pipe is communicated with the bottom end opening of the pipe body; and the pressure assembly is positioned in the pipe body and used for driving the welding flux to move into the discharging pipe.

In some alternative embodiments, the extrusion mechanism extrudes the solder on the substrate surface with a spacing of no more than 5mm between the bottom end of the tapping pipe and the substrate surface.

In some alternative embodiments, the extrusion mechanism is used to extrude the solder on the surface of the substrate at a distance of 0.2mm from the leads of the patch element.

In some alternative embodiments, the extrusion mechanism extrudes the solder at a unit mass of 20mg.

In some alternative embodiments, the molding pen includes: the pen holder and the hemispherical pen point positioned at the bottom end of the pen holder; wherein the cambered surface of the pen point faces downwards; and a layer of wool fiber for reducing the contact area with the solder is wound on the pen point.

In some alternative embodiments, the molding pen pushes the solder to move towards the connection point between the patch element and the liquid metal circuit through the pen point at the lower end of the molding pen; in the horizontal pushing process, the pen point moves from bottom to top in the vertical direction, so that the welding flux forms a slope attached to the side face of the patch element.

In some alternative embodiments, the solder is a viscous solid-liquid mixture of liquid metal and metal particles.

Another object of the invention is to propose a liquid metal printer comprising a welding mechanism as defined in any one of the preceding claims.

Compared with the prior art, the invention has the following advantages:

according to the invention, the conductive paste which is sticky at normal temperature is used as the solder, and the solder is used for plugging the connection part of the liquid metal circuit and the element pin, so that the conductive paste can be used as a conductive connecting agent for auxiliary connection of the liquid metal circuit and the element pin, and the problem of physical separation caused by penetration of colloid into the connection part in the subsequent sealing process can be avoided.

Drawings

FIG. 1 is a schematic diagram of a printing mechanism of a liquid metal printer in an embodiment of the invention;

FIG. 2 is a schematic diagram of a printing status of a liquid metal printer according to an embodiment of the present invention;

FIG. 3 is a schematic illustration of a liquid metal wire fusion effect;

FIG. 4 is a control flow diagram of a printing mechanism of the printing mechanism in an embodiment of the invention;

FIG. 5 is a schematic printing view of a printing mechanism in an embodiment of the present invention;

FIG. 6 is a schematic illustration of a liquid metal line printing effect in accordance with an embodiment of the present invention;

FIG. 7 is a flow chart of a repair of a liquid metal printer in an embodiment of the invention;

FIG. 8 is a flow chart of a repair of a liquid metal printer in an embodiment of the invention;

FIG. 9 is a schematic diagram of a liquid metal printer in an embodiment of the invention;

FIG. 10 is a schematic diagram of a repair mechanism of a liquid metal printer according to an embodiment of the present invention;

FIG. 11 is a schematic diagram of a repair mechanism of a liquid metal printer according to an embodiment of the present invention;

FIG. 12 is a schematic diagram of a repair mechanism of a liquid metal printer according to an embodiment of the present invention;

FIG. 13 is a schematic view of a wiper pen of a repair mechanism of a liquid metal printer in accordance with an embodiment of the present invention;

FIG. 14 is a schematic view of a wiper pen of a repair mechanism of a liquid metal printer in accordance with an embodiment of the present invention;

FIG. 15 is a schematic diagram of a liquid metal printer in an embodiment of the invention;

FIG. 16 is a schematic diagram of a patch mechanism of a liquid metal printer in an embodiment of the invention;

FIG. 17 is a schematic diagram illustrating the operation of the patch mechanism in an embodiment of the present invention;

fig. 18 is a schematic structural view of a component cassette of the patch mechanism in the embodiment of the present invention;

FIG. 19 is a schematic diagram of a patch mechanism of a liquid metal printer in an embodiment of the invention;

FIG. 20 is a schematic view of a dispensing head of a patch mechanism according to an embodiment of the present invention;

FIG. 21 is a schematic diagram of a welding mechanism of a liquid metal printer in accordance with an embodiment of the present invention;

FIG. 22 is a partial schematic view of a welding mechanism in an embodiment of the invention;

FIG. 23 is a schematic diagram of the operation of a welding mechanism in an embodiment of the invention;

FIG. 24 is a partial schematic view of a welding mechanism in an embodiment of the invention;

FIG. 25 is a schematic diagram of a liquid metal printer in an embodiment of the invention;

fig. 26 is a schematic partial structure of a liquid metal printer in an embodiment of the invention.

Detailed Description

The following description and the drawings sufficiently illustrate specific embodiments of the invention to enable those skilled in the art to practice them. Other embodiments may involve structural, logical, electrical, process, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in, or substituted for, those of others. The scope of embodiments of the invention encompasses the full ambit of the claims, as well as all available equivalents of the claims. These embodiments of the invention may be referred to herein, individually or collectively, by the term "invention" merely for convenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept if more than one is in fact disclosed.

Referring now to fig. 1, fig. 1 shows a schematic structural diagram of a liquid metal printer according to an embodiment of the present invention, and as shown in the schematic structural diagram, a liquid metal printer 100 includes: a working surface (working table) 10, and a printing mechanism 20 for performing a printing job on the working surface 10, the printing mechanism 20 being for printing a liquid metal in a fluid state onto a printing substrate 201 placed on the working surface 10 in a predetermined pattern to form a liquid metal printed pattern, thereby drawing the pattern as a printed wiring of a printed circuit or as a decorative liquid metal.

The liquid metal in the embodiment of the invention can be one or more of mercury, gallium, indium, tin simple substance, gallium indium alloy, gallium indium tin alloy, gallium zinc alloy, gallium indium zinc alloy, gallium tin zinc alloy, gallium indium tin zinc alloy, gallium tin cadmium alloy, gallium zinc cadmium alloy, bismuth indium alloy, bismuth tin alloy, bismuth indium zinc alloy, bismuth tin zinc alloy, bismuth indium tin zinc alloy, tin lead alloy, tin copper alloy, tin zinc copper alloy, tin silver copper alloy and bismuth lead tin alloy. The low-melting point metal has excellent conductivity and liquid phase fluidity, so that the low-melting point metal has unique application value in the field of manufacturing novel electronic structures. Wherein the liquid metal on both the printing mechanism 20 and the printing substrate 201 is in a fluid state with a melting point below 100 degrees celsius (for the alloys described above, the alloy ratio is selected by the melting point curve in the phase diagram of the alloy), and in some embodiments the liquid metal is in a fluid molten state by heating.

In some preferred embodiments, the liquid metal may be a low melting point metal that is liquid at normal temperature (35 degrees celsius), such as a gallium-indium alloy, with a specific gallium-indium ratio of 75.5% gallium and 24.5% indium, and a melting point of 15.5 degrees, which is substantially in liquid form at normal temperature.

In some embodiments, printing mechanism 20 moves jobs in one or more directions over a work surface via a robotic arm or single/multi-axis linkage assembly.

The printing mechanism 20 adopts a liquid metal direct-writing type printing head 21, is similar to a direct-writing pen/writing pen, and forms a track line which is consistent with a moving track on a printing substrate by taking out liquid metal in a pen tube through the movement of a pen ball on the printing substrate, thereby forming a target pattern and a figure. The print head 21 and the ink cartridge 22 are communicated with each other through a pipe 23.

Compared with an ink-jet printing mode, the liquid metal direct-writing type printing head has the advantages that although the ink output of the liquid metal is easier to control, the printed liquid metal patterns and patterns still have the problems that the printing quality is affected, such as line shrinkage, line interruption, line overflow and the like.

One important reason for affecting printing quality is the surface tension of the liquid metal in the fluid state, so that the liquid metal wire just printed on the surface of the printing substrate drives the liquid metal in a certain area to converge towards the center of the area due to the action of the surface tension until the gravity and the surface tension of the liquid metal in the area reach balance and stability, and the phenomenon is similar to the convergence phenomenon of liquid drops.

In order to solve the above problems, the present invention also proposes an image forming method for a liquid metal direct-writing printhead, i.e. the printing mechanism 20, so as to avoid the phenomenon of line shrinkage and even line breakage as much as possible, improve the stability and reliability of the liquid metal printing process, and ensure the quality of the liquid metal printed product.

As shown in fig. 2, the pattern forming method includes: forming a molten metal pattern by sequentially drawing at least 2 liquid metal lines on a working surface; at least 2 liquid metal wires are mutually overlapped along the width direction when being drawn.

The overlapping of the two liquid metal wires in the line width direction means that a certain range of overlapping exists between the two liquid metal wires in the line width direction, and the overlapping range is uniform in the extending direction (perpendicular to the line width direction) of the liquid metal wires.

In some embodiments, the two liquid metal wires that overlap each other are identical in size, shape, and parallel to each other, and the liquid metal wires overlap completely; in other embodiments, the two overlapping liquid metal wires are not uniform in overall size and shape, wherein one liquid metal wire is uniform in local shape with the other liquid metal wire and parallel to each other, overlapping is realized, and the liquid metal wires are locally overlapped; in other embodiments, the two mutually overlapped liquid metal wires are inconsistent in overall size and shape, and the two liquid metal wires are respectively provided with local mutual correspondence, so that the local overlapping of the liquid metal wires is realized;

In some embodiments, the at least 2 liquid metal lines overlap each other in a line width direction when drawn, and specifically includes: according to the drawing sequence, the liquid metal wires are sequentially overlapped one by one along the width direction. That is, the liquid metal lines 1020 formed by the later drawing overlap the liquid metal lines 1010 formed by the earlier drawing, and the filling of the patterns is realized by overlapping each other.

The graph in the embodiment of the invention can comprise a plurality of standard polygons such as line segments, circular arcs, squares (including positive rectangles and rectangles), circles (including ellipses), triangles, five deformations and the like, and can also be a non-standard polygon graph. The pattern is composed of one or more patterns, which may be continuous or separated. The pattern may be, for example, a printed circuit comprising: a plurality of conductive traces (for making two electrical connections, such as component pin-component pin, component pin-power line), pads, vias, etc.; the conductive line may be a line segment of any line shape.

The liquid metal direct-writing printing method disclosed by the embodiment mainly utilizes a gradual drawing/filling mode to enable one liquid metal line to form a target graph and a target pattern.

Firstly, the liquid metal lines which are drawn at present are drawn by being lapped on another liquid metal line which is drawn and formed (partially overlapped), namely, the liquid metal lines are drawn in a one-by-one mode, compared with the liquid metal lines which are formed by a printing head with wider single line width (or the single line width is controlled to be widened) (namely, the target line width can be obtained by one stroke), the line width of the single liquid metal line is thinner, and the line shrinking range is reduced.

In addition, from the contact surface of liquid metal and substrate surface, the pen bead of the printer head in this scheme has formed the extrusion face that distributes evenly in the region of liquid metal circuit, and the liquid metal that is in this position is owing to the pressure that the pen bead applyed has improved the infiltration effect with printing between the substrate, comparatively stable adhesion on the substrate surface, through the extrusion face that the extrusion line that distributes evenly constitutes, can follow bottom restriction liquid metal circuit holistic size, shape and carry out the restriction to a certain extent.

Furthermore, from the surface of the liquid metal, the overlapping drawing in the scheme can enable the liquid metal to be mutually fused, and although the influence of surface tension cannot be completely avoided, the convergence of the liquid metal line from the bottom of the edge to the center can be greatly reduced due to the stable structure (stable adhesion) distributed uniformly on the bottom of the liquid metal.

Therefore, the invention fuses and forms the complete liquid metal graph/pattern by a mode of overlapping a plurality of single lines, reduces the line shrinkage effect caused by the surface tension of the liquid metal to a certain extent, improves the stability and the reliability of the liquid metal direct-writing printer, and ensures the printing quality of the formed liquid metal pattern.

Referring now to fig. 3, fig. 3 shows a schematic view of the effect of different overlap ranges between single lines.

In fig. 3a, the liquid metal wires are designed by adopting a single line width as an offset step of the printing head, that is, the overlap range between the liquid metal wires is 0, and the liquid metal wires should be just connected in an ideal state, but in practice, the liquid metal wires are separated from each other due to the action of the surface tension of the liquid metal.

The design of the offset step length between the liquid metal single wires in fig. 3b is smaller than that of a single wire width, but the overlapping range of the single wires is smaller, and the overlapping part is insufficient to overcome the surface tension (stress point) of the respective single wires, so that the phenomenon of breaking due to the surface tension still can exist.

The design of the offset step length between the liquid metal single lines in fig. 3c is smaller than the single line width, but the overlapping range of the single lines is larger, and the contact surface area of the two single line restructured line groups with the printing substrate is insufficient to bind the liquid metal in the area, namely the gravity of the liquid metal is larger than the surface tension of the liquid metal in the area, so that the problem of non-directional overflow of the liquid metal in the area can be caused.

The design that the offset step length is smaller than the single line width is adopted between the liquid metal single lines in the figure 3d, and the single line overlapping range is not too small or too large, so that the stable existence of the liquid metal lines is ensured.

Further, when the overlapping range between the liquid metal element wires is not less than 20% of the line width of a single wire, the problem shown in fig. 3b can be significantly improved. The problem shown in fig. 3c can be avoided when the overlap range between the liquid metal single lines does not exceed 80% of the single line width. Namely, when the overlapping range is in the region between 20% and 80% of the single line width, the defect problem generated by printing the liquid metal line can be effectively improved, and the printing effect of fig. 3d is achieved.

In some preferred embodiments, when the overlapping range is set to 45% -60% of the single line width, the reliability and stability of the printed liquid metal line can be greatly improved, so that the structure of the fused liquid metal is stable, and the problems of deformation and overflow are not easy to occur.

Preferably, in an embodiment of the present invention, a pattern forming apparatus having one or more components performing the above-described pattern forming method is also disclosed.

Referring now to fig. 4, the present invention further proposes a liquid metal direct-write printing method for the liquid metal direct-write printing technology, which is applied to a liquid metal direct-write printer, and includes:

Step S21, generating a direct-write printing track to be executed according to the target pattern;

the target pattern may be a combination of one or more target patterns, and the target patterns include linear (line), rectangular, circular arc and other regular or irregular patterns.

Step S22, executing the direct-writing printing track to form a molten metal pattern;

the direct-writing printing track comprises at least one filling track indicating that a unit pattern is formed by drawing a plurality of liquid metal wires, and the offset step length in the filling track does not exceed a single line width.

In the embodiment of the present invention, technologies in the prior art, such as collection of pixel points, coordinate setting, and the like, and existing software for manufacturing and/or processing electronic circuits may be used for collection, identification, positioning, and the like of the target pattern.

In some embodiments, the offset step in the fill track is 40% -55% of the single line width. The printing effect of fig. 3d described above can be achieved.

Taking the rectangle shown in fig. 5 as a target graph example, a direct-writing type printing head is adopted, a pen point adopts a ball with the diameter of 0.5mm, the ink output is controlled to be constant, the average line width of a corresponding single pen is 0.15mm, and the offset step length of the direct-writing type printing head is set to be 0.6-0.8mm. The direct writing track adopts a gradual detour type drawing mode, the leftmost side above is set as a starting point, then liquid metal wires are detour printed in sequence from left to right and from top to bottom, and the liquid metal wires move downwards by 0.6-0.8mm each time. Until all the drawing of the target graph is completed. In this embodiment, the target pattern is drawn by a pen-forming method, and in other embodiments, after printing the liquid metal line of the row is completed, the print head is lifted to move down (shift), and then the print head is pressed down to continue to print the liquid metal line of the row horizontally, so that a larger amount of liquid metal at the position caused by printing at the shift position is avoided.

In some embodiments, the target pattern includes at least 2 consecutive unit patterns; the process of generating the direct-writing printing track to be executed according to the target pattern comprises the following steps: and (3) adjusting the offset step length within the range of 40% -55% of the single line width to enable the direct writing end point of the unit pattern drawn in advance to be continuous with the direct writing start point of the unit pattern drawn in the later.

In some embodiments, the write-through print track indicates one-shot molding or multi-shot molding of the metal pattern.

The printing method can be used for any graph and pattern drawn by liquid metal, such as aesthetic planar printing products, such as planar drawing; and the intelligent drawing with conductive characteristics, such as touch LED lamp decoration liquid metal drawing, is rich in aesthetic feeling; and printed wiring in a standard Printed Circuit (PCB), comprising: the wiring itself, the patch contact wiring, the pad location, the via location, etc.

Preferably, in an embodiment of the present invention, a liquid metal printer is also disclosed, which has one or more components for performing the printing method described above.

In summary, circuit defects such as circuit break points, circuit irregularities/imperfections (i.e., the circuit is still connected but does not meet standard line width/line shape, such as hollowness and edge shrinkage), circuit overflow and the like are easily generated in the liquid metal printed pattern, and the defects should be repaired in different ways, for example, the liquid metal can be added at the break point position or the missing position for the circuit break points and the circuit imperfections, and the overflowed liquid metal should be removed for the circuit overflow problem. Fig. 6 shows various printing effects of liquid metal, fig. 6 (a) is a normal liquid metal line, fig. 6 (b) is a line break, fig. 6 (c) is a line hollow, and fig. 6 (d) is a line break caused by obvious line shrinkage.

Referring now to fig. 7, fig. 7 shows a repair flow chart when the above-mentioned defects (shrinkage, break, overflow, imperfections) are present due to the liquid metal pattern/graphic, as shown in the flow chart, the repair method comprises:

s31, sweeping a target graph/pattern to obtain a line defect of liquid metal in the target graph/pattern;

the method for scanning the target graph/pattern in the step can be a snapshot method, such as shooting and photographing, or a projection recognition method (such as CCD photosensitive image sensor), the actual condition of the actual target graph/pattern can be obtained through the brightness of the projection generated after the lighting, then the difference between the two images is found out through comparing the original graph/pattern, and the line defect in the line defect is analyzed;

the method for comparing the two pixel images can adopt the pixel point technology in the prior art, an original circuit image is firstly split into a plurality of pixel points, each pixel point corresponds to one coordinate point, the area occupied by liquid metal in the original circuit image can be recorded as 1, the rest area can be recorded as 0, when the actual circuit image of a target circuit is obtained, the circuit image is split into the pixel points according to the mode and is correspondingly marked, and then the two pixel images are compared, so that the pixel points and the position coordinates of the difference of the two pixel points are found.

And S32, judging the defect type of the line defect, and selecting a corresponding repair strategy according to the defect type to supplement or erase the liquid metal to the line defect.

The invention solves the quality problem brought by different defects to the drawing of the liquid metal by adopting different repairing modes.

In particular, as described above,

a line defect, comprising: line breaks and/or line incompleteness; the step S32 of selecting a corresponding repair strategy according to the defect type to repair or erase the line defect with liquid metal may specifically include: and determining a liquid metal line segment where the line defect is located, and a starting point and an end point of the line defect, and replenishing liquid metal on the liquid metal line segment in a region between the starting point and the end point.

Line defects, may further include: line overflow; the step S32 of selecting a corresponding repair strategy according to the defect type to repair or erase the line defect with liquid metal may specifically include: acquiring an overflow area; and controlling the wiping head dipped with alcohol to wipe the overflow area with a certain force.

As shown in fig. 8, in some alternative embodiments, before the scanning the target pattern/pattern, further comprises:

S30, preparing the target circuit by using a liquid metal direct-write printing technology;

the process comprises the following steps: and drawing a liquid metal line segment in a repeated reciprocation detour mode, wherein the printing head is offset to a specified direction by a certain offset step before detour printing, and the offset step is smaller than the single line width of the printing head. Wherein the selection of the offset step size may be selected from the range of offset step sizes above.

In some embodiments, the replenishing the liquid metal on the liquid metal line segment in a region between the start point and the end point specifically includes: and (3) replenishing the liquid metal in the area between the starting point and the end point on the liquid metal line segment by adopting the liquid metal direct-writing printing technology.

As described above for the operation of the liquid metal printer, the printer needs to calculate the working track when the liquid metal line is drawn by the print head before controlling the print head to form the liquid metal line segment, in one embodiment, each segment is taken as a line segment unit, the liquid metal printer continues to print the next line segment unit after printing one line segment unit, and each line segment unit corresponds to a printing logic/printing instruction of the liquid metal printer, where the printing logic/printing instruction instructs the liquid metal printer to print the liquid metal line segment according to the preset working track, and the printing start point, the end point, the offset step length, the pressing degree of the print head, the printing speed and the like are included in the working track.

In some embodiments, when the line defect is the line break, the adding the liquid metal to the area of the liquid metal line segment between the start point and the end point specifically includes: and calling a printing instruction of the liquid metal line segment where the line defect is located, replacing the head-tail coordinates of the liquid metal line in the printing instruction by the starting point and the tail point, and executing the replaced printing instruction to supplement the line break point on the liquid metal line segment.

The repairing strategy in the embodiment can be completed without regeneration by replacing the specified parameters by the original printing instruction, so that the calculated amount of the liquid metal printer is reduced, and the integral printing efficiency of the liquid metal printer is improved.

In some embodiments, when the line defect is a line defect, the adding the liquid metal to the area between the start point and the end point on the liquid metal line segment specifically includes: acquiring the line width of a missing region of a line, and recalculating the offset step length of the printing head according to the line width; and calling a printing instruction of the liquid metal line segment where the line defect is located, replacing the head-tail coordinates of the liquid metal line in the printing instruction by the starting point and the tail point, replacing the original detour offset in the printing instruction by the detour offset obtained by recalculation, and executing the replaced printing instruction to supplement the area with the incomplete line.

Because the line is incomplete, the line width is changed, and the repairing effect is possibly influenced when the line is printed according to the offset step length in the original printing instruction, the offset step length is recalculated, so that the problem is avoided, and the quality of the liquid metal line is ensured.

Specifically, the obtaining the line width of the missing area of the line, and recalculating the offset step length of the print head according to the line width specifically includes: recalculating the offset step of the printhead according to the following formula; s= (X-D/N); n= ((X-D)/D) +1; wherein S is the offset step length calculated again, X is the line width of the missing area of the line, D is the initial offset step length, and N is the detour number needed for filling the missing area of the line. Wherein the detour times are rounded up.

Specifically, before the step of recalculating the offset step of the print head according to the line width, the method further includes: judging the size relation between the line width X of the missing area of the line and the initial offset step length D; if X is more than or equal to D, recalculating the offset step length of the printing head according to the line width; if X < D, filling a liquid metal by using the central line of the missing area of the line.

In some embodiments, before the determining the defect type of the line defect, the method further includes: judging the duty ratio of the line defect in the whole liquid metal line in the target graph/pattern; if the duty ratio exceeds the threshold value, discarding the current target graph/pattern, and reprinting; otherwise, judging the defect type of the line defect, and selecting a corresponding repair strategy according to the defect type to supplement or erase the liquid metal to the line defect.

This embodiment is used to avoid the problem of ineffective repair due to complex causes, and thus avoid entering repeated dead cycles. In some embodiments, the threshold includes a ratio of the liquid metal line segment where the line defect is located throughout the liquid metal line, and a ratio of an area affected by the line defect throughout the liquid metal line; preferably, the threshold is specifically a 60% ratio of the liquid metal line segment where the line defect is located in the whole liquid metal line, and a 30% ratio of the area affected by the line defect in the whole liquid metal line. One or two of the thresholds can be used, and if the actual defect condition in the printed circuit exceeds the threshold, the repair time exceeds the first preparation time, so that the whole preparation time is overlong.

Preferably, the embodiment of the invention also discloses a liquid metal printer, which is provided with one or more components for executing the repairing method, such as a first component, for sweeping a target graph/pattern and acquiring the line defect of the liquid metal in the target graph/pattern; the second component is used for judging the defect type of the line defect, selecting a corresponding repair strategy according to the defect type, and adding or erasing liquid metal to the line defect; and a third component for preparing the target circuit using a liquid metal direct write printing technique.

Referring now to fig. 9, fig. 9 shows another schematic structural diagram of a liquid metal printer according to an embodiment of the present invention, and as shown in the schematic structural diagram, the present invention discloses a liquid metal printer 100, where the liquid metal printer 100 further includes, on the basis of fig. 1: the pattern acquisition system comprises a strip-shaped lamp belt 91 positioned below the working surface 10 and a CCD system 92 positioned above the working surface 10, wherein the strip-shaped lamp belt and the CCD system are vertically opposite. The working surface is made of transparent materials, the strip-shaped lamp belt is used for providing a light source right above the strip-shaped lamp belt, and the CCD system above the strip-shaped lamp belt is used for obtaining an image formed on the printed substrate by penetrating the light source, so that an actual printed pattern is obtained. The obtained actual pattern can be applied to the scanning target pattern in the repairing method, so that the line defect is obtained through analysis, and then the printing head is driven to repair the target pattern. The repair is mainly directed to line breaks and line imperfections of the liquid metal lines/patterns.

In a preferred embodiment, the CCD system above the work surface 10 and the strip-shaped light belt below the work surface are identical in size and vertically opposite to each other, and cover the print substrate 201 on the work surface 10, and when the image is collected, the printing mechanism 20 is controlled to return to its original position (a position that does not affect the collection of the image), and the actual print pattern is once obtained by the strip-shaped light belt and the CCD system.

In another preferred embodiment, the strip-shaped light strip located below the working surface 10 can be reciprocally moved in one direction with the moving direction as its width and the other direction as its length, the CCD system covers the printing substrate 201 on the whole working surface 10, the length of the strip-shaped light strip corresponds to the CCD system, and the width of the strip-shaped light strip is smaller than the CCD system, and the CCD system obtains the actual printed pattern by the movement of the strip-shaped light strip.

In another preferred embodiment, the CCD system above the work surface 10 and the strip-shaped light strip below the work surface are identical in size and vertically opposite, and do not cover the entire printing substrate 201, and the printing substrate 201 is moved by the driving assembly, so that the CCD system obtains an actual printing pattern. In this embodiment, the positions of the strip-shaped light belt and the CCD system can be fixed, and the size is small, so that the whole printer is miniaturized and simply designed. The drive assembly may employ a pinch roller that rotates to drive the horizontal movement of the printed substrate 201.

Referring now to fig. 10, fig. 10 shows a schematic structural diagram of a repair mechanism 30 for wiping repair of line overflow defects in a liquid metal line/pattern, comprising: the wiping head 31 is soaked with the wiping agent, and the moving component 32 drives the wiping head 31 to move in the horizontal and/or vertical directions, and the moving component can adopt a mechanical arm, a single-shaft/multi-shaft linkage component, an electromagnetic driving moving component and the like.

In the wiping operation, the wiping head 31 is attached to the printing substrate 201, and erases the overflowed liquid metal on the printing substrate 201 in a predetermined trajectory.

Further, the repairing mechanism 30 includes: a fibre wiping head 31, a container 34 containing a wiping agent and an electrically controlled lifting mechanism 32; the bottom of the fiber wiping head 31 is used for wiping target liquid metal on the surface of the substrate in a horizontal movement mode, the fiber wiping head 31 is in contact connection with a wiping agent in the container 34, the wiping agent always maintains to infiltrate the fiber wiping head 31 through the infiltration effect, the fiber wiping head 31 is in matched connection with the electric control lifting mechanism 32, and the bottom of the fiber wiping head 31 is contacted with or separated from the surface 201 of the substrate under the driving of the electric control lifting mechanism 32; wherein, when the bottom of the fiber wiping head 31 is contacted with the substrate surface 201, the wiping operation of the target liquid metal on the substrate surface is realized by the horizontal movement of the fiber wiping head 31 or the horizontal movement of the substrate. The wiping agent in the container 34 in fig. 9 is held in contact with the fiber wiping head by means of liquid-conducting fibers in the conduit 33, preferably cotton fibers, which maintain good penetration.

The electric control lifting mechanism 32 can be controlled by two gears (or more than two gears), namely, the electric control lifting mechanism 32 controls the bottom of the fiber wiping head 31 to be contacted with the surface of the base material according to the preset contact degree (can be set by selecting the installation position of the fiber wiping head 31) in the operation gear, and the electric control lifting mechanism 32 controls the bottom of the fiber wiping head 31 to be lifted away from the surface of the base material in the non-operation gear. In other embodiments, the electric control lifting mechanism 32 can freely drive the fiber wiping head 31 to move at any position in the vertical direction, and the precision displacement of the fiber wiping head 31 in the vertical direction can be realized through a motor or electromagnetic traction and corresponding matching structures.

The fiber wiping head 31 can be made of cotton fiber, glass fiber or polymer fiber, such as plastic fiber, high strength sponge, etc.; for glass fibers and polymer fibers, one or more fine channels are provided therein for holding the fiber wiping head 31 with a small amount of wiping agent for wiping the liquid metal. The diameter length of the bottom of the fiber wiping head 31 is between 0.25mm and 5 mm; preferably, the repairing mechanism 30 can adopt fiber wiping heads 31 with different materials and different diameters for wiping off overflowed liquid metal in different ranges/positions; wherein, the bottom diameter of the fiber wiping head 31 adopting cotton fibers can be between 2mm and 5mm for wiping off overflowed liquid metal in a large range; the bottom diameter of the fiber wiping head 31 using polymer fibers or glass fibers may be between 0.25mm and 2mm for precise wiping of spilled liquid metal.

The end of the bottom of the fiber wiping head 31 adopts a flat structure to prevent inconsistent contact of the cambered surface structure to the surface of the substrate and damage of the liquid metal circuit connected with the overflowed liquid metal. The end of the tube can be round or square.

The repairing mechanism 30 provided by the invention can automatically repair the overflow defect of the circuit in the printed circuit in the preparation process of the printed circuit, ensures the quality of the finished product of the liquid metal printed circuit, and improves the preparation stability and reliability of the liquid metal printed circuit.

The wiping agent can be ethanol or a solution with the main component of ethanol, such as absolute ethanol, ethanol and a liquid mixture which is mixed with volatile grease and has the alcohol content of 75-99 percent, the liquid mixture can be used for wiping out overflowed liquid metal on one hand, and the grease can form an anti-overflow path at the overflow side line of the liquid metal circuit on the other hand, so that the liquid metal circuit is isolated and protected. The alcohol itself can also form the above-mentioned square overflow path, and the grease is more ideal for isolation.

As shown in fig. 11, the repairing mechanism 30 may further include: a horizontal movement mechanism 35 that moves in one or more directions along a horizontal plane; the fiber wiping head 31 and the electrically controlled lifting mechanism 32 are assembled on the horizontal moving mechanism 35, that is, for example, the electrically controlled lifting mechanism 32 is fixed on the horizontal moving mechanism 35, and the fiber wiping head 31 is fixed on the electrically controlled lifting mechanism 35 following the movement of the horizontal moving mechanism 35 in the horizontal direction, thereby realizing the movement in the horizontal (x and y) direction and the vertical (z) direction.

As shown in fig. 12, the container 34 is a pen tube 36 filled with the wiping agent, the bottom of the pen tube is opened and is blocked by the fiber wiping head 31, and the bottom of the fiber wiping head 31 is exposed out of the pen tube 36 to form a pen point of the pen tube 36. In contrast, the electrically controlled lifting mechanism 32 may employ an attracting electromagnet; the magnetizer 37 on the attracting electromagnet 32 is connected with the pen tube 36 through a cross beam bracket 38; the pen tube 36 follows the attracting movement of the magnetizer 37 through the cross beam bracket 37.

As shown in fig. 12 and 13, the repairing mechanism 30 may further include: a pen holder 39 fixed to the horizontal movement mechanism 35; the pen holder 39 has a vertical through hole, the shape of which corresponds to the diameter surface of the pen tube 36, the pen tube 36 is located in the through hole, and a support is formed on the pen holder 39 by the first clamping structure 361 and the elastic member 362; when the attracting electromagnet 32 is electrified, the upper magnetizer 37 drives the pen tube 36 to move downwards to the working position, and at the moment, the elastic piece 362 is compressed and deformed; when the attracting electromagnet 32 is de-energized, the elastic member 362 is released to release and move the pen tube 36 upward to its initial position. In some embodiments, the restoring force of the pen tube 36 in the vertical direction may be provided by a side of the attracting electromagnet 32, such as a spring between the magnetizer 37 and the electromagnet 32 in fig. 11.

As shown in fig. 14, the pen holder 39 may be a cylindrical structure for preventing the pen 36 from being shifted in the horizontal direction when moving in the vertical direction, a first clamping table 363 is disposed above the inside of the pen holder 36, a second clamping structure 364 cooperating with the first clamping table 363 is disposed above the inside of the pen holder 36 for limiting the maximum ascending height of the fiber wiping head 31 (e.g., the length of the pen holder 39 extending the minimum), a second clamping table 365 is disposed below the inside of the pen holder 36, and a third clamping structure 366 cooperating with the second clamping table 365 is disposed below the inside of the pen holder 36 for limiting the maximum descending height of the fiber wiping head 31 (e.g., the length of the pen holder 39 extending the maximum)

Referring now to fig. 15, fig. 15 shows another schematic diagram of a liquid metal printer according to an embodiment of the present invention, and as shown in the schematic diagram, the present invention discloses a liquid metal printer 100, including: the repairing mechanism 30.

In some preferred embodiments, the liquid metal printer 100 further comprises: a working surface 10, a printing mechanism 20 and an image acquisition system. The printing mechanism 20 is used for performing liquid metal printing operation on the printing substrate 201 on the working surface 10 and repairing defects such as liquid metal break points, incomplete defects, edge shrinkage and the like; the repairing mechanism 30 is used for repairing defects such as liquid metal overflow.

The printing mechanism 20 and the patching mechanism 30 may adopt the structure in the above embodiment, and the image acquisition system may adopt image technologies such as photographing, image capturing, projection and the like.

When the printing mechanism 20 is performing a printing/repair job, the repair mechanism 30 may be in an initial position, i.e., not affecting the movement job of the printing mechanism 20; when the repairing mechanism 30 performs the repairing operation, the printing mechanism 20 can be at the initial position, that is, the moving operation of the repairing mechanism 30 is not affected; when the image acquisition system works, the printing mechanism 20 and the repairing mechanism 30 can be in initial positions, so that the image acquisition of the image acquisition system is prevented from being influenced.

The liquid metal printer in the embodiment can realize the integrated preparation of liquid metal printing products (such as liquid metal printed circuits), does not need to repair liquid metal patterns printed by the liquid metal printer manually, and improves the reliability of the liquid metal printer.

With continued reference to fig. 15, the printing mechanism 20 and the repairing mechanism 30 are both assembled on the same rail beam, the rail beam moves in the Y-axis direction, the rail beam spans the printing substrate 201 from above the working face 10, the rail beam has a slide rail along its length direction, the printing mechanism 20 and the repairing mechanism 30 are assembled on the slide rail to move in the X-axis direction, in the initial state, the printing mechanism 20 and the repairing mechanism 30 are located at both ends of the rail beam, outside the printing substrate 201, and when it works, the printing mechanism 20/the repairing mechanism 30 move inward through the slide rail to be located directly above the printing substrate 201, and move the printing substrate 201 on the working face 10 through the slide rail and the rail beam.

In some embodiments, the liquid metal printer 100 further comprises: one or more pinch rollers that frictionally move the printed substrate 201 into the work surface 10 and on the work surface 10 in the Y-axis direction. In this embodiment, the printing mechanism 20 and/or the repairing mechanism 30 in the liquid metal printer 100 can cooperate with the pinch roller to drive the printing substrate 201 to move relative to the printing substrate 201.

In this embodiment, the printing mechanism 20 and the repairing mechanism 30 are located on the same rail beam, so that the equipment space of the liquid metal printer is saved, and excessive moving mechanisms in the liquid metal printer are avoided, thereby simplifying hardware equipment of the liquid metal printer.

Referring now to fig. 16 and 17, the present invention discloses a patch mechanism 40 comprising: a tube-type patch gun 41, an element box 42, a dispensing head 43, a first movable component, a second movable component, a third movable component and a pneumatic system. Wherein,

the tubular patch gun 41 is linked with a first movable mechanism and is used for sucking the patch element 203 through the bottom suction nozzle 411 and moving the patch element 203 to working surfaces with different heights through the first movable mechanism; the top of the tube-shaped patch gun 411 is communicated with a first air duct 44 of an air pressure system, and the suction and release of the suction nozzle 411 are controlled by starting/stopping of negative pressure. Preferably, a flexible washer is arranged outside the suction nozzle 411, so as to avoid the suction nozzle 411 from being in direct rigid contact with the patch element 203, reduce gaps possibly generated between the suction nozzle 411 and the patch element 203, and solve the problems of loose and loose suction of the suction nozzle 411 to the patch element 203.

According to the invention, the dispensing head is turned upside down, and dispensing is performed on the bottom surface of the patch element, so that various problems that the dispensing head from the lower part is easily influenced by gravity, the colloid leakage is caused, the dispensing amount is not easy to control and the like are avoided.

The first movable mechanism can adopt a lifting mechanism, and different gears are arranged for working surfaces with different heights, so that the tube-shaped patch gun 41 is controlled to stay on the working surfaces with different heights; wherein the working surface may include a mounting working surface, a dispensing working surface and a pasting working surface, and is used for sucking the pasting component 203 under the suction nozzle 411 when the pasting working surface is located; the dispensing operation surface is used for dispensing the bottom surface of the patch element 203 adsorbed under the suction nozzle 411; in the bonding operation surface, the bonding element 203 for dispensing the bottom surface is placed on a prescribed position of the liquid metal pattern 202 on the printing substrate 201, and a certain degree of (slight) pressing is generated.

In another embodiment, the lifting mechanism may also perform any height movement in the vertical direction in units of distance, preferably measured in millimeters. The first movable mechanism can be driven by a motor, electromagnetism, pressure (such as air pressure/hydraulic pressure) and the like.

The component box 42 is linked with a second moving mechanism, and can be a slot body structure with a sealed upper part or a box body structure with a window arranged at a specific position, wherein a space for placing one or more patch components 203 is arranged in the box body structure, and the patch components 203 in the box body structure are moved to the position right below the suction nozzle 411 of the tubular patch gun 41 through the second moving mechanism at a certain moment (when the patch loading work is needed); preferably, the component case 42 has a structure for bundling the chip components 203 therein so as to ensure that the chip components 203 sucked under the suction nozzles 411 can be attached to the designated positions of the printed wiring 202 at a predetermined angle.

Preferably, the second moving mechanism may adopt a horizontal moving mechanism (such as a sliding rail 421 and a matching electromagnetic member 422) for driving or driving the component box 42 to move horizontally in a horizontal direction with a certain height, so that the patch component 203 reaches below the working position of the tubular patch gun 41 and leaves the falling range of the tubular patch gun 41; preferably, the second moving mechanism may adopt a two-stage control, that is, the position of the element box 42 is not blocked from falling down of the tube-shaped patch gun 41 in the initial stage, and the designated area of the element box 42 is located right under the tube-shaped patch gun 41 in the working stage. The second movable mechanism can be driven by a motor, electromagnetism, pressure (such as air pressure/hydraulic pressure) and the like.

Preferably, the second moving mechanism includes: a slide rail 421 mated with the housing of the component cassette; the component cassette is ejected or retracted in the horizontal direction along the slide rail by the electromagnetic member 422.

In some alternative embodiments, as shown in fig. 18, the component cassettes are stacked in a vertical direction in multiple layers 423, each layer 423 being moved in a horizontal direction by separate slide rails 421 and electromagnetic members 422. The element box is of an L-shaped groove body structure, and the widths of the groove bodies are consistent; one or more dispensing units 424 which are consistent in appearance and arranged in sequence are contained in the container, the chute body forms a chute 425 of the dispensing unit, and the dispensing unit 424 moves from one end to the other end of the chute body through electromagnetic members 426 and 427; wherein, the upper surface of the dispensing unit 424 is provided with a placement groove 428 corresponding to the shape of the patch element; the component box is used for moving the patch component 203 in the component box to the position right below the suction nozzle of the tubular patch gun 41 at a certain moment through the second moving mechanism, and specifically comprises: the component box 42 moves the patch component 201 at the bending position of the component box 42 to the position right below the suction nozzle 411 of the tubular patch gun 41 by the driving of one or more electromagnetic members.

As shown in fig. 19, the dispensing head 43 is linked with a third movable mechanism, and is in an inverted structure, and the dispensing nozzle 431 is vertically upward, so as to move to a position right below the chip component 203 adsorbed under the suction nozzle 411 at a certain moment (when the dispensing operation is required), and perform the dispensing operation on the bottom surface of the chip component 203 through the dispensing nozzle 431.

In some embodiments, the bottom of the dispensing head 43 is communicated with the glue storage tank 433 through a pipeline 432, the glue storage tank 433 is used for storing a certain amount of glue, the pipeline 432 adopts a hard pipeline, and the dispensing head 43 is communicated with and relatively fixed to the glue storage tank 433 through the hard pipeline 432. The third movable mechanism can adopt a rotating mechanism, and the rotating mechanism drives the glue storage tank 433 to rotate, so that the glue dispensing head 43 linked with the glue storage tank 433 is indirectly driven to displace by taking the glue storage tank 433 as the circle center. The dispensing head 43 is driven by the rotating mechanism to move to a position immediately below the chip component 203 sucked under the suction nozzle 411 and to leave the falling range of the tube-shaped chip gun 41.

As shown in fig. 20, in some embodiments, a magnetic thimble 435 that moves up and down is disposed in the glue outlet 431 of the dispensing head 43 through a bracket 434, and an end face of the magnetic thimble 435 is in a planar structure, and when the magnetic thimble 435 is at its lowest position, its top end is located below the glue liquid level; the tubular patch gun 41 is provided with an electromagnet 412 cooperating with the magnetic thimble 435, so that the magnetic thimble 435 is sucked out of the glue outlet 431 in the electrified state, and the glue point carried by the end of the magnetic thimble 435 is on the bottom surface of the patch element 203. In some alternative embodiments, the top end of the magnetic thimble 435 is provided with a flexible fiber for attaching a colloid, and the fiber may be cotton fiber or plastic fiber, and is easy to squeeze and deform when stressed, so that the direct stress of the patch element 203 can be reduced, and the patch element is prevented from being deflected/falling due to impact. Preferably, the flexible fibers are cotton fibers having fine interstices therein with a small amount of glue adhered thereto.

The colloid is light-cured colloid or heat-cured colloid, preferably, the heat-cured colloid with the curing temperature above 60 ℃.

In some embodiments, the patch mechanism 40 further comprises: and a fourth moving mechanism for driving the tubular patch gun 41, the component box 42 and the dispensing head 43 to move in a vertical direction and/or a horizontal direction in a consistent manner. Preferably, the fourth movable mechanism may be an x, y, z axis moving carriage of the liquid metal printer.

Another object of the present invention is to propose a method for attaching the patch mechanism 40 to solve the problems in the prior art.

The surface mounting method is applied to the surface mounting mechanism and comprises the following steps:

s41, initializing equipment to enable the tubular patch gun to be located on an initial working surface;

step S42, driving a second movable mechanism to drive a component box to move a target patch component to the position right below the suction nozzle of the tubular patch gun;

step S43, driving a first movable mechanism to drive the tubular patch gun to move downwards to a loading working surface, and adsorbing a target patch element under a suction nozzle;

step S44, driving a second movable mechanism to drive the element box to move out of the falling range of the tubular patch gun;

Step S45, driving a third movable mechanism to drive the dispensing head to move to the position right below the target element adsorbed under the suction nozzle;

step S46, driving a first movable mechanism to drive the tubular patch gun to move downwards to a dispensing working surface, and finishing dispensing of the bottom surface of the target patch element by matching with the dispensing head;

step S47, driving a third movable mechanism to drive the dispensing head to move out of the falling range of the tubular patch gun;

step S48, driving the first movable mechanism to drive the tubular patch gun to move downwards to the patch working surface, and stopping the adsorption operation, so that the target patch element is placed at a designated position of the base material with the liquid metal circuit on the surface.

The invention also provides a liquid metal printer 100, and the assembly comprises the patch mechanism 40. The liquid metal printer 100 of this embodiment can be used not only for preparing liquid metal printed patterns/printed circuits, but also for mounting elements, thereby realizing integrated preparation of printed circuits.

Referring now to fig. 21, fig. 21 shows a soldering mechanism 50 according to an embodiment of the present invention, which is used to seal and fix a connection between a liquid metal printed circuit 202 and a pin of a chip element 203 by using a metal mixture (conductive mixture) that is viscous at normal temperature. A welding mechanism 50 comprising: the molding machine comprises a horizontal moving mechanism 51, a first lifting mechanism 52, a second lifting mechanism 53, an extrusion molding mechanism 54 and a molding pen 55, wherein the first lifting mechanism 52 and the second lifting mechanism 53 are fixed on the horizontal moving mechanism 51, are linked in the horizontal direction along with the movement of the horizontal moving mechanism 51, the extrusion molding mechanism 54 is arranged on the first lifting mechanism 52, moves along with the first lifting mechanism 52 in the vertical direction, the molding pen 55 is arranged on the second lifting mechanism 53, and moves along with the second lifting mechanism 53 in the vertical direction, and the movement of the first lifting mechanism 52 and the movement of the second lifting mechanism 53 in the vertical direction are independent.

The extruding mechanism 54 has a vertically downward discharge port for extruding a unit mass (or metering a unit volume) of solder onto the surface of the substrate directly below the extruding mechanism, and the solder adopts a viscous metal mixture at normal temperature, which has good conductivity, and in some preferred embodiments, the metal mixture is a solid-liquid mixture obtained by uniformly mixing metal particles (such as silver-coated copper powder and copper powder) with liquid metal, and the liquid metal is selected to have a consistent proportion with the components of the liquid metal printed on the surface of the substrate, so that wettability and fusion between the solder and the liquid metal circuit are improved, and stable connection between the solder and the liquid metal circuit is ensured.

As shown in fig. 22, the extrusion molding mechanism 54 includes a tube 541 for accommodating solder, wherein the bottom of the tube 541 has a tapered necking structure for converging the solder, a discharge tube 542 is vertically fixed at the opening, and the discharge tube 542 has a hollow tube structure and is communicated with the interior of the tube 541; and a pressure component 543 located in the pipe body 541 and configured to drive the solder to move into the discharge pipe 542, where the pressure component 543 may use a mechanical extrusion manner, for example, an extrusion screw, and drive the solder to move toward the discharge pipe 542 by rotating the extrusion screw.

The pressure assembly 543 may also be configured as shown in fig. 23 to force solder through the ram 544 into the tapping pipe. The upper end of the discharging pipe 542 is located inside the pipe body 541, the pressure head 544 moves in the vertical direction through electromagnetic driving, the end of the pressure head 544 is of a notch structure, the shape of the pressure head corresponds to the pipe orifice of the discharging pipe 542, the pipe orifice of the discharging pipe 542 can be covered, when the pressure head 544 moves downwards to squeeze solder, the notch of the pressure head 544 can accommodate part of the solder, when the pressure head 544 moves to the pipe orifice of the discharging pipe 542, the notch and the pipe orifice are mutually squeezed and matched, and the solder in the notch is squeezed from the pipe orifice of the discharging pipe 542 to squeeze the material inlet and outlet pipe. With this structure, the unit extrusion amount of solder can be controlled.

As shown in fig. 24, in some embodiments, the molding pen 55 includes: the pen holder 551 and the hemispherical pen point 552 positioned at the bottom end of the pen holder 551; wherein the cambered surface of the pen point 552 faces downwards; the brush head 552 is wound with a layer of wool, which can reduce the contact area with the liquid metal due to the small gaps, and the surface property of the wool can prevent the liquid metal from adhering to the brush head, so that the brush head can be prevented from being carried with solder in the pushing process. The plastic pen pushes the welding flux to move towards a connection point between the patch element and the liquid metal circuit through a pen point at the lower end of the plastic pen; in the horizontal pushing process, the pen point moves at a uniform speed from bottom to top in the vertical direction, so that the welding flux forms a slope attached to the side surface of the patch element. The slope-shaped surface packaging adhesive enters the joint between the liquid metal circuit and the pin of the patch element, so that the liquid metal circuit and the pin of the patch element can flow along the slope.

The working flow of the printed circuit soldering mechanism in the embodiment of the invention is as follows:

step 1, the substrate is moved in the y direction, and the extrusion molding mechanism is driven to move in the x direction by the horizontal moving mechanism, so that a discharge pipe of the extrusion molding mechanism is opposite to a preset solder extrusion point, and preferably, the distance between the solder extrusion point and a pin of the patch element is set to be 0.2 mm.

Step 2, driving the extrusion molding mechanism to move along the vertical direction through the first lifting mechanism so that the extrusion molding mechanism is positioned at a position with a height of 5mm from the surface of the printing substrate;

step 3, driving a pressure mechanism in the extrusion molding mechanism to extrude a unit volume of solder on the surface of the substrate, wherein the solder can fall through the cooperation of a conventional vibration or shaking assembly;

step 4, lifting the extrusion molding mechanism, and moving the molding pen to one side of the solder away from the pins of the patch element, wherein the pen point of the molding pen is lower than the height of the solder (namely, the pen point and the solder are partially overlapped in the vertical direction);

And 5, controlling the pen point of the molding pen to drive the solder to move towards the pin direction of the patch element, and gradually lifting the pen point in the process to enable the solder to form a slope with gradually enlarged height along the moving direction of the solder so as to be attached to the side wall of the patch element.

The invention discloses a liquid metal printer 100, comprising: a working surface 10, a patch mechanism 40, and a welding mechanism 50; the paster mechanism 40 and the welding mechanism 50 are assembled on the same guide rail beam, the guide rail beam moves along the Y-axis direction, the guide rail beam stretches across the printing substrate 201 from the upper side of the working surface 10, a sliding rail along the length direction of the guide rail beam is arranged on the guide rail beam, the paster mechanism 40 and the welding mechanism 50 are assembled on the sliding rail and move along the X-axis direction, in an initial state, the paster mechanism 40 and the welding mechanism 50 are positioned at two ends of the guide rail beam and are positioned at the outer side of the printing substrate 201, and when the paster mechanism 40/the welding mechanism 50 work, the paster mechanism 40/the welding mechanism move inwards through the sliding rail and move to be positioned right above the printing substrate 201 and move the printing substrate 201 on the working surface 10 through the sliding rail and the guide rail beam.

In some embodiments, the liquid metal printer 100 further comprises: one or more pinch rollers that frictionally move the printed substrate 201 into the work surface 10 and on the work surface 10 in the Y-axis direction. In this embodiment, the pasting mechanism 40 and/or the soldering mechanism 50 in the liquid metal printer 100 can cooperate with the pressing wheel to drive the printing substrate 201 to move relative to the printing substrate 201.

In this embodiment, the patch mechanism 40 and/or the welding mechanism 50 are located on the same rail beam, which saves the equipment space of the liquid metal printer, and avoids excessive moving mechanisms in the liquid metal printer, thereby simplifying the hardware equipment of the liquid metal printer.

Referring now to fig. 25, fig. 25 shows a schematic structural diagram of a liquid metal printer in an embodiment of the present invention, as shown in the schematic structural diagram, a liquid metal printer 100, comprising: the printing mechanism 20, the repairing mechanism 30, the pasting mechanism 40, the welding mechanism 50 and the packaging mechanism 60 are driven by one or more moving mechanisms to move above the working surface 10. Wherein the working surface 10 is used for bearing a printed substrate 200; the printing mechanism 20 is used for drawing a liquid metal pattern 202 on a printing substrate 201; the repairing mechanism 30 is used for repairing defects in the liquid metal pattern 202 formed on the printing substrate 201; the patch mechanism 40 is used for placing the patch element 203 at a designated position on the liquid metal pattern 202 (the liquid metal pattern is used as a printed circuit for forming a printed circuit) formed on the printed substrate 201, so that pins of the patch element 203 are in contact connection with the liquid metal printed circuit reserved at the position; the soldering mechanism 50 is used for dripping solder at the pins of the patch element mounted on the printed substrate 20 and realizing pin packaging of the pins and the liquid metal printed circuit, and the solder adopts a viscous liquid metal mixture at normal temperature; the encapsulation mechanism 60 is used to apply an encapsulation paste to the surface of the formed printed circuit to achieve hermetic encapsulation.

The work surface 10 comprises a first work surface 11 and a second work surface 12 in succession, including direct and indirect connections, each for transferring the printed substrate 201 from the first work surface 11 to the second work surface 12; specifically, the first working surface 11 is used for the working operations of the printing mechanism 20, the repairing mechanism 30, the pasting mechanism 40, and the welding mechanism 50, and the second working surface 12 is used for the working operations of the packaging mechanism 60. That is, the liquid metal printer 100 performs liquid metal printing, repairing, pasting and foot wrapping on the printing substrate 201 on the first working surface 11, transfers the printing substrate from the first working surface 11 to the second working surface 12 after finishing the above operation, and at this time, the liquid metal printer 100 performs packaging operation on the printing substrate on the second working surface 12, and after the packaging adhesive is cured, the finished liquid metal printed circuit or liquid metal printed pattern is obtained. Preferably, the liquid metal printer 100 further comprises a transfer mechanism 70, wherein the transfer mechanism 70 is configured to transfer the printing substrate from the first working surface 11 to the second working surface 12.

The liquid metal printer 100 further comprises a main control board, and the main control board is used for receiving user instructions and driving various mechanisms in the liquid metal printer 100 to perform corresponding movements and operations.

The liquid metal printer in the embodiment of the invention not only solves the automatic repair of the liquid metal circuit/pattern defects, but also improves the reliability of integrated preparation of printing, repairing, pasting, welding (foot wrapping) and packaging based on the automatic repair, and ensures the printing quality.

Specifically, the first working surface 11 and the second working surface 12 are continuous and bent in a zigzag shape to form two high and low working surfaces, the high working surface being the first working surface 11 and the low working surface being the second working surface 12. Preferably, the second working surface 12 is provided with one or more packaging grooves for placing one or more printing substrates and performing packaging operations respectively. The packaging mechanism adopts a two-component flexible colloid or a two-component hard colloid, such as AB glue.

Each of the working mechanisms in the liquid metal printer 100 in this embodiment may adopt a structure disclosed in any of the working mechanisms described above, in which the moving members of the driving working mechanism in the horizontal and vertical directions may be shared with each other.

With continued reference to fig. 25, a preferred construction of the liquid metal printer of the present invention is disclosed in this embodiment, comprising: a frame 80, a first rail beam 81 and a second rail beam 82 that move in the Y-axis direction across the first work surface 11, and a third rail beam 83 that moves in the Y-axis direction across the second work surface 12; the first guide rail beam 81, the second guide rail beam 82 and the third guide rail beam 83 are erected on the frame 80, Y-axis direction sliding rails are arranged at corresponding positions on the frame 80, and the first guide rail beam 81, the second guide rail beam 82 and the third guide rail beam 83 move along the Y-axis direction through the Y-axis direction sliding rails. The movement range of the first rail beam 81 and the second rail beam 82 is limited to the area of the first work surface 11, and the movement range of the third rail beam 83 is limited to the area of the second work surface 12.

The printing mechanism 20 and the repairing mechanism 30 are aimed at the operation of the liquid metal line, and therefore both mechanisms are arranged on the first rail beam 81, so that the printing mechanism 20 and the repairing mechanism 30 are driven to move along the Y-axis direction through the first rail beam 81. The first guide rail beam 81 is provided with an X-axis direction sliding rail along the extending direction thereof, the printing mechanism 20 and the repairing mechanism 30 are connected with the first guide rail beam 81 through the X-axis direction sliding rail and realize the X-axis direction movement along the first guide rail beam 81, preferably, the initial positions of the printing mechanism 20 and the repairing mechanism 30 on the first guide rail beam 81 are the two ends of the beam, the operation of any mechanism on a printing substrate is not affected, the width of the printing substrate is the middle section between the two ends of the beam 81, and when one of the two mechanisms is in an operation state, the other mechanism is positioned at the initial position and stands by.

The bonding mechanism 40 and the welding mechanism 50 are directed to the operation of the bonding element, and therefore both mechanisms are disposed on the second rail beam 82, so that the bonding mechanism 40 and the welding mechanism 50 are driven to move in the Y-axis direction through the second rail beam 82. The second rail beam 82 is provided with an X-axis direction sliding rail consistent with the first rail beam 81 along the extending direction thereof, and the assembly, movement, position, and cooperative working state of the patch mechanism 40 and the welding mechanism 50 on the second rail beam 82 are consistent with those of the printing mechanism 20 and the repairing mechanism 30 on the first rail beam 81, which will not be described herein.

As shown in fig. 26, the transfer mechanism 70 includes: and the pressing wheels are arranged below the first guide rail beam 81 and the second guide rail beam 82 and are used for contacting the printing base material to prevent the printing base material from deviating, and the printing base material is driven to move along the Y-axis direction by friction force. The substrate moving mechanism 70 is configured to adjust the position of the print substrate in the region of the first working surface 11 in cooperation with the first rail beam 81 and the second rail beam 82, thereby achieving that the target mechanism is opposed to the designated position of the print substrate. The movement mechanism is based on the other hand on the transfer of the printing substrate from the first work surface 11 into a second work surface 12 which is continuous with the first work surface 11.

In some embodiments, first work surface 11 is positioned directly in front of second work surface 12, with opposing first rail beam 81, second rail beam 82, and third rail beam 83 disposed in sequence from proximal to distal. The liquid metal printer is arranged in such a way as to meet the requirements of the preparation process of the liquid metal printer.

The image acquisition mechanism 90 may adopt an image acquisition system such as photographing, image capturing and the like; preferably, the first working surface 11 is made of a light-transmitting hard material; the image acquisition mechanism is provided with a strip-shaped lamp strip below the first working surface 11 and is used for providing a light source upwards; and a projection pattern recognition system disposed above the first rail beam 81 and the second rail beam 82, opposite to the first working surface 11 in the vertical direction, for recognizing an actual print image by projection formed by irradiating the print substrate with a light source. Such as a charge coupled device image sensor CCD system. Specifically, the strip-shaped lamp belt is fixed in position and opposite to the projection pattern recognition system in the vertical direction, and the substrate moving mechanism drives the printing substrate to move along the Y-axis direction, so that the surface image of the whole printing substrate is recognized.

Another objective of the present invention is to provide a method for manufacturing a printed circuit, which is applied to the liquid metal printer 100, and includes:

step a, feeding a blank printed substrate into a first working surface;

b, printing liquid metal on the printing substrate to form a liquid metal printed circuit;

c, performing quality inspection on the liquid metal printed circuit formed on the printed substrate; step e, if the quality inspection is qualified, entering a step d, otherwise, entering a step d;

step d, correspondingly repairing the circuit defects existing in the liquid metal printed circuit; step c is entered;

step e, picking up the electronic element to be attached to the printed substrate and connecting the electronic element with a designated position in the liquid metal printed circuit;

step f, coating the solder which is sticky at normal temperature on the joint of the liquid metal printed circuit and the electronic element, and fixing the package foot;

step g, transferring the printing substrate from the first working surface to the second working surface;

and h, dripping packaging glue on the printed substrate, packaging the liquid metal printed circuit and the electronic element on the printed substrate, and obtaining the printed circuit after the packaging glue is leveled and solidified.

In some illustrative embodiments, after one or more of steps e and f are performed, the quality inspection (e.g., step c) may be performed again on the liquid metal printed circuit formed on the printed substrate, and if the quality inspection is qualified, the downward movement may be performed, otherwise, the repair operation is started.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

Claims

1. A welding mechanism, comprising:

an extrusion mechanism moving in a vertical direction for extruding a unit mass of solder onto a surface of a substrate located directly therebelow; wherein the solder is a viscous metal mixture at normal temperature;

a molding pen moving along the vertical direction and the horizontal direction, which is used for pushing the solder extruded on the surface of the substrate and enabling the solder to wrap the connection point between the pin of the patch element and the liquid metal circuit on the surface of the substrate in a certain shape;

A horizontal moving mechanism, a first lifting mechanism and a second lifting mechanism which are arranged on the horizontal moving mechanism;

the extrusion molding mechanism is arranged on the first lifting mechanism, and is driven to move along the vertical direction by the first lifting mechanism;

the molding pen is arranged on the second lifting mechanism, is driven to move in the vertical direction by the second lifting mechanism, and is driven to move in the horizontal direction by the horizontal moving mechanism;

wherein, extrusion molding mechanism includes:

the bottom of the tube body is of a conical mouth structure converging the solder;

the top end of the vertically arranged discharging pipe is communicated with the bottom end opening of the pipe body;

the pressure assembly is positioned in the pipe body and used for driving the welding flux to move into the discharging pipe;

wherein, mould the type pen and include: the pen holder and the hemispherical pen point positioned at the bottom end of the pen holder; wherein the cambered surface of the pen point faces downwards; a layer of wool fiber for reducing the contact area with the solder is wound on the pen point;

the molding pen pushes the welding flux to move towards a connection point between the patch element and the liquid metal circuit through a pen point at the lower end of the molding pen; in the horizontal pushing process, the pen point moves from bottom to top in the vertical direction, so that the welding flux forms a slope attached to the side face of the patch element.

2. The welding mechanism of claim 1, wherein the extrusion mechanism extrudes the solder on the substrate surface at a distance of no more than 5mm between the bottom end of the tapping pipe and the substrate surface.

3. The soldering mechanism of claim 1, wherein the extrusion mechanism is configured to extrude the solder on the surface of the substrate at a distance of 0.2mm from the leads of the patch element.

4. The soldering mechanism according to claim 1, wherein the unit mass of the solder extruded by the extrusion mechanism is 20mg.

5. The soldering mechanism of claim 1, wherein the solder is a viscous solid-liquid mixture of liquid metal and metal particles.

6. A liquid metal printer comprising a welding mechanism as claimed in any one of claims 1 to 5.