High-precision dispensing device and corresponding dispensing needle position correction method

Abstract

The invention provides a high-precision dispensing device and a corresponding dispensing needle position correction method. The dispensing device comprises a cross beam, a dispensing mechanism, a transfer platform, a positioning mechanism and a cleaning mechanism. The transfer platform is arranged below the dispensing mechanism in a sliding mode, the dispensing mechanism moves in the X direction, the Y direction and the Z direction which are perpendicular to one another relative to the transfer platform, the positioning mechanism is located on one side of the transfer platform and used for correcting the position of a dispensing needle of the dispensing mechanism, and the cleaning mechanism is located below the track of the dispensing mechanism. The positioning mechanism comprises a mounting frame, an X-direction correlation sensor, a Y-direction correlation sensor and a Z-direction pressure sensor, sensing paths of the X-direction correlation sensor and the Y-direction correlation sensor intersect, the intersection point is used as a correction point, and the Z-direction pressure sensor is located below the correction point. And the X-direction correlation sensor, the Y-direction correlation sensor and the Z-direction pressure sensor are fixedly connected with the same mounting frame, so that the mounting error is small, and the dispensing precision and quality can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of dispensing device, in particular to a high-precision dispensing device and a corresponding position correction method of dispensing needle. BACKGROUND

[0002] The dispensing device is an automatic or semi-automatic equipment for precisely controlling and dispensing fluid materials such as glue, sealant, lubricant, solder paste, etc. Its core goal is to apply fluid in the right place, with the right amount, and with the right shape, which is an indispensable key process equipment in modern manufacturing industry.

[0003] For example, the dispensing device can be used in the assembly process of the display screen, and the backlight source is fixed by dispensing, the optical film is attached, and the edge is sealed. The precision and quality of the dispensing process directly determine the structural strength, dustproof and light leakage performance of the backlight module, and ultimately affect the brightness uniformity and long-term reliability of the display screen.

[0004] There are many factors that affect the dispensing precision and quality, such as the position correction of the dispensing needle. Some dispensing devices in the prior art will set laser probes at different positions, which will hit the side of the needle tip to achieve correction. However, setting multiple laser probes at different positions is more likely to cause installation errors, which will be converted into systematic measurement errors, thereby affecting the dispensing precision and quality.

[0005] Therefore, it is necessary to provide a high-precision dispensing device and a corresponding position correction method of dispensing needle to solve the above technical problems. SUMMARY

[0006] The present application provides a high-precision dispensing device and a corresponding position correction method of dispensing needle to solve the problem of low dispensing precision and quality of the dispensing device in the prior art.

[0007] To solve the above technical problems, the technical scheme of the present application is as follows: a high-precision dispensing device, comprising: a crossbeam, a dispensing mechanism, a transfer platform, a positioning mechanism and a cleaning mechanism; The dispensing mechanism is slidably connected to the crossbeam, the transfer platform is slidably arranged below the dispensing mechanism, the dispensing mechanism has X, Y and Z directions perpendicular to each other relative to the transfer platform, the positioning mechanism is located on one side of the transfer platform for position correction of the dispensing needle of the dispensing mechanism, and the cleaning mechanism is located below the trajectory of the dispensing mechanism for cleaning the dispensing needle of the dispensing mechanism. The positioning mechanism comprises a mounting frame, an X-direction opposite emission sensor, a Y-direction opposite emission sensor and a Z-direction pressure sensor, the X-direction opposite emission sensor is arranged on the opposite sides of the mounting frame, the Y-direction opposite emission sensor is arranged on the other opposite sides of the mounting frame, the sensing paths of the X-direction opposite emission sensor and the Y-direction opposite emission sensor are located on the inner side of the mounting frame, the sensing paths of the X-direction opposite emission sensor and the Y-direction opposite emission sensor intersect, and the intersection point is a correction point, and the Z-direction pressure sensor is located below the correction point.

[0008] In the application, the X-direction opposite emission sensor and the Y-direction opposite emission sensor each comprise a transmitting part and a receiving part, and the transmitting part and the receiving part of the X-direction opposite emission sensor and the Y-direction opposite emission sensor are arranged through the inside of the mounting frame. The bottom of the mounting frame is connected with a mounting plate through a connecting rod, and the Z-direction pressure sensor is fixedly arranged on the mounting plate.

[0009] In the application, the high-precision point glue device further comprises a plurality of adsorption columns, the inside of the adsorption column is provided with an airflow channel, the top of the adsorption column is provided with a suction disc in communication with the airflow channel, one side of the adsorption column is provided with a connecting head in communication with the airflow channel, and the bottom of the adsorption column is provided with a magnet block, and the adsorption column is movably arranged on the top surface of the transfer platform through the magnet block.

[0010] Among them, a plurality of adsorption columns include a cylindrical adsorption column and a rectangular block-shaped adsorption column, the opposite sides of the rectangular block-shaped adsorption column are respectively provided with a connecting block and a connecting groove, and the connecting block and the connecting groove can connect two adsorption columns. The connecting block comprises a convex edge strip convexly arranged on both sides, the inside of the connecting groove is provided with a clamping groove for clamping the convex edge strip, one side of the rectangular block-shaped adsorption column is further provided with an inlet groove, the inlet groove is communicated on the side close to or away from the suction disc of the connecting groove, and the slot length and width of the inlet groove are greater than the corresponding length and width of the connecting block.

[0011] In the application, the cleaning mechanism comprises a vertical fixing plate, a driving motor, a dust-free cloth, a cleaning clamp and a material receiving roller, a material discharging roller and a guide roller rotatably arranged on one side of the vertical fixing plate. The material receiving roller is connected with the output end of the driving motor, the dust-free cloth is wound on the material receiving roller, the guide roller and the material discharging roller in sequence, a straight strip section for cleaning the point glue needle is formed between two guide rollers of the dust-free cloth, the cleaning clamp is connected with the vertical fixing plate, and the straight strip section is arranged between two clamping blocks of the cleaning clamp.

[0012] The cleaning mechanism further comprises a cloth pressing assembly, which is located at one side of the cleaning clamp along the moving direction of the dust-free cloth and is located at the front end of the cleaning clamp along the moving direction of the dust-free cloth, and the cloth pressing assembly comprises an upper pressing block and a lower pressing block, the top of the lower pressing block is provided with a V-shaped groove, the bottom of the upper pressing block is provided with a V-shaped block corresponding to the V-shaped groove, and the straight bar section is arranged between the V-shaped block and the V-shaped groove, so that the straight bar section forms a V-shaped space for wrapping the dispensing needle when the cleaning clamp clamps the straight bar section.

[0013] Further, the cleaning mechanism further comprises a guide plate connected with the vertical fixed plate, the top surface of the guide plate is provided with a limiting groove, the limiting groove is a V-shaped structure, the straight bar section passes through and is limited in the limiting groove, and the cleaning clamp is located between the cloth pressing assembly and the guide plate.

[0014] In addition, the cleaning mechanism further comprises a counting sensor and a no-material photoelectric sensor, the sensing end of the counting sensor is connected with one of the guide rollers, the no-material photoelectric sensor is connected with the vertical fixed plate, and the emitting part and the receiving part of the no-material photoelectric sensor are located on the two sides of a section of the dust-free cloth between the feeding roller and the cleaning clamp.

[0015] In the application, the cleaning mechanism further comprises a waste glue collecting cup, which is arranged on the side of the vertical fixed plate away from the cleaning clamp.

[0016] The application further comprises a position correction method of a dispensing needle, which is controlled by a controller to correct the position of the dispensing needle by using the high-precision dispensing device, and comprises the following steps. Step S11: The controller is preset with a dispensing coordinate system, the controller acquires the preset position information of the dispensing needle and the correction point in the dispensing coordinate system, and controls the dispensing needle to move to the preset position of the correction point. Step S12: If the controller receives the sensing signals of the dispensing needle sent by the X-direction photoelectric sensor and the Y-direction photoelectric sensor, the X-direction data and the Y-direction data of the preset position of the correction point are taken as the X-direction data and the Y-direction data of the actual position. If the controller does not receive sensing signals from the X-axis and Y-axis through-beam sensors indicating that the dispensing needle has been detected, the controller controls the dispensing needle to move along the X and / or Y axes until sensing signals from the X-axis and Y-axis through-beam sensors indicating that the dispensing needle has been detected are received. The X-axis and Y-axis data of the current position of the dispensing needle are used as the actual X-axis and Y-axis data of the correction point. Based on the preset position of the correction point and the actual X-axis and Y-axis data, the XY-axis coordinate offset compensation is calculated. Based on the XY-axis coordinate offset compensation, the X-axis and Y-axis data of the preset position of the dispensing needle are updated to the actual X-axis and Y-axis data. Step S13: The sensing end of the Z-axis pressure sensor is a set distance away from the calibration point. Based on the fact that both the X-axis and Y-axis through-beam sensors have sensed the dispensing needle, the dispensing needle is controlled to descend along the Z-axis until it contacts the sensing end of the Z-axis pressure sensor. The descent stops when the Z-axis pressure sensor senses a preset pressure value. Based on the Z-axis data of the sensing end of the Z-axis pressure sensor and the Z-axis data of the preset position of the dispensing needle, the Z-axis coordinate offset compensation is calculated. Based on the Z-axis coordinate offset compensation, the Z-axis data of the preset position of the dispensing needle is updated to the Z-axis data of the actual position. Step S14: During the process of the dispensing needle descending along the Z direction, the X-direction through-beam sensor and the Y-direction through-beam sensor continuously sense the dispensing needle. If the controller does not receive the sensing signal from the X-direction through-beam sensor and the Y-direction through-beam sensor indicating that the dispensing needle has been sensed, it is determined that the dispensing needle has angular sway and an alarm is issued.

[0017] Compared to existing technologies, the advantages of this invention are as follows: The high-precision dispensing device of this invention accurately obtains the horizontal position of the needle through cross-sensing of X-axis and Y-axis through-beam sensors; the Z-axis pressure sensor achieves vertical contact detection, realizing high-precision three-dimensional spatial calibration of the dispensing needle. Simultaneously, integrating the X-axis, Y-axis, and Z-axis through-beam sensors onto the same mounting frame reduces cumulative installation errors and improves the consistency of coordinate system calibration.

[0018] Among them, the sensing signals of the X-axis and Y-axis through-beam sensors are continuously monitored during the descent of the dispensing needle along the Z-axis. This allows for real-time detection of whether the needle is deflected or bent, providing timely alarms and preventing a decline in dispensing quality due to abnormal needle posture.

[0019] In addition, the adsorption column is movably arranged on the top surface of the transfer platform through a magnet block, so that flexible arrangement can be realized according to the shape of the workpiece, the workpiece of different sizes and shapes can be quickly positioned and stably fixed, the displacement of the workpiece in the dispensing process is reduced, the consistency of the dispensing position is improved, and the dispensing quality is improved. Meanwhile, the rectangular block-shaped adsorption column can be spliced through the connecting block and the connecting groove, and after splicing, the connection stability with the transfer platform is higher, and the universality and recombination flexibility of the workpiece adsorption are improved.

[0020] The cleaning mechanism is provided with a cloth pressing assembly and a guide plate to cooperate with the cleaning clamp, so that the dust-free cloth can be naturally folded in the length direction to form a V-shaped cavity wrapping the needle, the dust-free cloth can stably wrap the dispensing needle to clean, the cleaning is more sufficient and complete, the glue filament or blockage is reduced, the dispensing quality is improved, the running time of each moving cycle is short, the cleaning efficiency is high, the dust-free cloth is saved, and the glue on the dust-free cloth is not easy to fall off, and the cleaning quality is high. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments are briefly introduced as follows, and the drawings in the following description are only corresponding to some embodiments of the present application.

[0022] Figure 1 The structure diagram of the preferred embodiment of the high-precision dispensing device of the present application.

[0023] Figure 2 The structure diagram of the positioning mechanism in the present application.

[0024] Figure 3 The structure diagram of the transfer platform in the present application.

[0025] Figure 4 The structure diagram of the adsorption jig in the present application.

[0026] Figure 5 The structure diagram of the cleaning mechanism in the present application.

[0027] Figure 6 The structure diagram of the cleaning mechanism in the present application. Figure 5 The structure diagram of the cleaning mechanism in the present application.

[0028] Figure 7 The local structure diagram of the cloth pressing assembly in the present application.

[0029] Figure 8 The structure diagram of the guide plate in the present application.

[0030] Figure 9 The structure diagram of the connecting block arranged on one side of the movable adsorption column in the present application.

[0031] Figure 10 Structure diagram of the connecting groove provided on one side of the movable adsorption column in the present application. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0033] The directional terms mentioned in the present application, such as "up", "down", "front", "back", "left", "right", "inner", "outer", "side", "top" and "bottom", are only the orientation of the drawings, and the directional terms are used to illustrate and understand the present application, but not to limit the present application.

[0034] The terms "first", "second" and the like in the present application are only for the purpose of description, and cannot be understood as indicating or implying relative importance, and are not limited as the order of sequence.

[0035] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, the connection can be detachable connection, or integral structure connection; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0036] The dispensing device in the prior art has the problems of low dispensing precision and dispensing quality. There are many factors that cause low dispensing precision and dispensing quality, such as the correction precision of the dispensing needle, the stability of the positioning and fixing of the workpiece by the transfer platform, and the like.

[0037] The following is a preferred embodiment of a high-precision dispensing device provided by the present application which can solve the above technical problems.

[0038] Please refer to Figure 1 and Figure 2 , wherein Figure 1 is a structure diagram of the preferred embodiment of the high-precision dispensing device of the present application. Figure 2 is a structure diagram of the positioning mechanism in the present application.

[0039] In the drawings, similar elements are denoted by the same reference numerals.

[0040] The embodiment provides a high-precision dispensing device, which comprises a beam 11, a dispensing mechanism 12, a transfer platform 13, a positioning mechanism 14 and a cleaning mechanism 15.

[0041] The dispensing mechanism 12 is slidably connected with the beam 11, the transfer platform 13 is slidably arranged below the dispensing mechanism 12, the dispensing mechanism 12 has X-direction, Y-direction and Z-direction movements perpendicular to each other relative to the transfer platform 13, and it is easy to understand that the X-direction, the Y-direction and the Z-direction are three perpendicular directions. The positioning mechanism 14 is located on one side of the transfer platform 13 and is used for position correction of a dispensing needle of the dispensing mechanism 12, and the cleaning mechanism 15 is located below a track of the dispensing mechanism 12 and is used for cleaning the dispensing needle of the dispensing mechanism 12.

[0042] Please refer to Figure 2 In the embodiment, the positioning mechanism 14 comprises a mounting frame 141, an X-direction opposite emission sensor 142, a Y-direction opposite emission sensor 143 and a Z-direction pressure sensor 144, the X-direction opposite emission sensor 142 is arranged on opposite sides of the mounting frame 141, the Y-direction opposite emission sensor 143 is arranged on the other opposite sides of the mounting frame 141, the sensing paths of the X-direction opposite emission sensor 142 and the Y-direction opposite emission sensor 143 are located inside the mounting frame 141, the sensing paths of the X-direction opposite emission sensor 142 and the Y-direction opposite emission sensor 143 intersect, and the intersection point is a correction point, and the Z-direction pressure sensor 144 is located below the correction point.

[0043] More specifically, the X-direction opposite emission sensor 142 and the Y-direction opposite emission sensor 143 each comprise a transmitting part and a receiving part, and the transmitting part and the receiving part of the X-direction opposite emission sensor 142 and the Y-direction opposite emission sensor 143 are arranged through the inside of the mounting frame 141. One end of the outside of the transmitting part and the receiving part can be used for wiring, and one end of the inside of the transmitting part and the receiving part is used for sensing light.

[0044] Preferably, the transmitting part and the receiving part of the X-direction opposite emission sensor 142 are respectively located in the middle of the opposite sides of the mounting frame 141, and the transmitting part and the receiving part of the Y-direction opposite emission sensor 143 are respectively located in the middle of the other opposite sides of the mounting frame 141, so that the correction point is also located in the middle of the inside space of the mounting frame 141.

[0045] The bottom of the mounting frame 141 is connected with a mounting plate 146 through a connecting rod 145, and the Z-direction pressure sensor 144 is fixedly arranged on the mounting plate 146. That is, the X-direction opposite emission sensor, the Y-direction opposite emission sensor and the Z-direction pressure sensor are all fixedly connected with the same mounting frame 141.

[0046] In the embodiment, the transfer platform 13 needs to be provided with an adsorption assembly for fixing the workpiece, wherein the adsorption assembly can be a plurality of movable adsorption columns 19 or an adsorption jig 16.

[0047] Please refer to Figure 4 , wherein the adsorption jig 16 comprises a jig plate body 161 and a plurality of fixed adsorption columns 162 arranged on the jig plate body 161, and the top surface of the transfer platform 13 is provided with a positioning hole and a connecting hole, the jig plate body 161 is positioned and connected with the positioning hole through a pin, and the jig plate body 161 is fixedly connected with the connecting hole through a screw. Thus, the adsorption jig 16 is positioned and fixed.

[0048] The inside of the fixed adsorption column 162 is provided with an airflow channel, and the top of the fixed adsorption column 162 is provided with a suction cup 1621 in communication with the airflow channel, and the airflow channel is connected with the output end of an external vacuum device. The fixed adsorption column 162 and the jig plate body 161 are an integral structure, and the adsorption jig 16 is a structure fully corresponding to the workpiece of a corresponding specification, which is a special jig. For a large number of same workpieces, using the adsorption jig 16 has higher work efficiency.

[0049] Please refer to Figure 3 , the inside of the movable adsorption column 19 is provided with an airflow channel, the top of the movable adsorption column 19 is provided with a suction cup 191 in communication with the airflow channel, one side of the movable adsorption column 19 is provided with a connecting head 192 in communication with the airflow channel, and the bottom of the movable adsorption column 19 is provided with a magnet block. The movable adsorption column 19 is movably arranged on the top surface of the transfer platform 13 through the magnet block.

[0050] The plurality of movable adsorption columns 19 are more suitable for workpieces of different specifications, and users can finely select and arrange according to the workpiece profile, stress points and avoidance requirements, so as to realize targeted support and adsorption of different workpieces of various shapes and size specifications, and further expand the application range of the equipment.

[0051] In the embodiment, the plurality of movable adsorption columns 19 can include movable adsorption columns of cylindrical structure and movable adsorption columns of rectangular block structure. At the same time, the diameters of the radial sections of the movable adsorption columns of cylindrical structure can not be equal, and the length and width of the radial sections of the movable adsorption columns of rectangular block structure can not be equal. Suitable movable adsorption columns 19 can be selected according to the space requirements of different positions of the workpiece, and the compatibility and flexibility are higher.

[0052] In the embodiment, the top of the movable adsorption column 19 of rectangular block structure is provided with one or more suction cups.

[0053] Please refer to Figure 9 and Figure 10Optionally, the movable adsorption column 19 of the rectangular block structure has a connecting block 21 and a connecting groove 22 on opposite sides, and the two movable adsorption columns 19 can be connected through the connecting block 21 and the connecting groove 22.

[0054] More specifically, the connecting block 21 includes a convex edge strip 211 protruding on both sides, the connecting groove 22 is provided with a clamping groove on both sides of the inner part for clamping the convex edge strip 211, and one side of the movable adsorption column 19 of the rectangular block structure is further provided with an inlet groove 23, which is connected on the side of the connecting groove 22 close to or away from the suction cup 191. The slot of the inlet groove 23 is longer and wider than the corresponding length and width of the connecting block 21. The connecting block 21 can be loaded from the inlet groove 23 and then clamped and connected to the connecting groove 22.

[0055] Through the connection of the connecting block 21 and the connecting groove 22, multiple movable adsorption columns 19 of the rectangular block structure can be connected. For the case that the workpiece has a larger adsorption and fixing space, multiple movable adsorption columns 19 of the rectangular block structure are spliced to adsorb and fix the workpiece, and the connection of the multiple movable adsorption columns 19 of the rectangular block structure with the transfer platform 13 is also more firm after forming a whole, which can increase the adsorption area and gripping force of a single column, has higher stability, and improves the dispensing quality. It can improve the versatility and recombination flexibility of the transfer platform, so that a larger movable adsorption column 19 does not need to be additionally manufactured, and the cost is lower.

[0056] Among them, the cleaning mechanism in the prior art generally bends the dust-free cloth along the width direction through the guide rollers, and the space formed between the two sides of the guide rollers at the bending part is used to clean the dispensing needle, so that the wiped dust-free cloth part needs to pass through the entire bending part completely, and the dust-free cloth needs more time for each moving cycle, and the waste and loss of the dust-free cloth are large.

[0057] Please refer to Figure 5 and Figure 6 The cleaning mechanism 15 in the embodiment includes a vertical fixed plate 151, a driving motor, a dust-free cloth 15B, a cleaning clamp 152, and a material receiving roller 153, a material feeding roller 154, and a guide roller 155 rotatably arranged on one side of the vertical fixed plate 151.

[0058] The material receiving roller 153 is connected with the output end of the driving motor, and the material receiving roller 153 and the driving motor are located on the two sides of the vertical fixed plate 151, respectively. The dust-free cloth 15B is wound on the material receiving roller 153, the guide roller 155, and the material feeding roller 154 in sequence, and a straight section 15B1 for cleaning the dispensing needle is formed between the two guide rollers 155. The cleaning clamp 152 is connected with the vertical fixed plate 151, and the straight section 15B1 is arranged between the two clamping blocks 1521 of the cleaning clamp 152 to form a stable cleaning section, which can realize automatic progression and replacement of the cleaning section.

[0059] The cleaning mechanism 15 further comprises a cloth pressing assembly 156, which is located at one side of the cleaning clamp 152 along the moving direction of the lint-free cloth 15B, and the cloth pressing assembly 156 is located at the front end of the cleaning clamp 152 along the moving direction of the lint-free cloth 15B (i.e. the lint-free cloth 15B passes through the cloth pressing assembly 156 first and then passes through the cleaning clamp 152).

[0060] Please refer to Figure 7 The cloth pressing assembly 156 comprises an upper pressing block 1561 and a lower pressing block 1562, and the top of the lower pressing block 1562 is provided with a V-shaped groove 15621, and the bottom of the upper pressing block 1561 is provided with a V-shaped block 15611 corresponding to the V-shaped groove 15621. The straight strip section 15B1 is arranged between the V-shaped block 15611 and the V-shaped groove 15621, so that when the cleaning clamp 152 clamps the straight strip section 15B1, the straight strip section 15B1 can form a V-shaped space for wrapping the dispensing needle.

[0061] The cloth pressing assembly 156 can pre-press the lint-free cloth 15B out of the V-shaped fold through the cooperation of the V-shaped block 15611 and the V-shaped groove 15621 before the lint-free cloth 15B is clamped. When the cleaning clamp 152 is clamped, the lint-free cloth 15B naturally forms a V-shaped cavity for wrapping the needle, so that the lint-free cloth 15B stably wraps the side wall of the dispensing needle, so that the wiping is more sufficient and thorough, and the residual glue is effectively removed to prevent silk hanging or blockage.

[0062] In this embodiment, the gap distance between the two side surfaces of the V-shaped block and the two inner side surfaces corresponding to the V-shaped groove is not equal. The side with smaller gap distance can stably limit the lint-free cloth 15B, and the side with larger gap distance can provide more adaptive space for the cleaning clamp 152 to clamp and control the lint-free cloth 15B.

[0063] Please refer to Figure 6 and Figure 8 Further, the cleaning mechanism 15 further comprises a guide plate 157, which is connected with the vertical fixed plate 151, and the top surface of the guide plate 157 is provided with a limiting groove 1573 in a V-shaped structure. The straight strip section 15B1 passes through and is limited in the limiting groove 1573, and the cleaning clamp 152 is located between the cloth pressing assembly 156 and the guide plate 157. The V-shaped limiting groove 1573 of the guide plate 157 also shapes the lint-free cloth 15B, so that the lint-free cloth 15B on both sides of the cleaning clamp 152 can form a V-shaped cavity, and the stable wrapping of the side wall of the dispensing needle by the lint-free cloth 15B is ensured.

[0064] The guide plate 157 comprises a first plate body part 1571 and a second plate body part 1572, which are connected as an L-shaped structure, a limiting groove 1573 is arranged on the first plate body part 1571, and the second plate body part 1572 is adjustably connected with the vertical fixing plate 151 through a long hole 1574, so as to adjust the contact force of the straight bar segment 15B1 with the first plate body part 1571.

[0065] Please refer to Figure 7 In addition, the two clamping blocks 1521 of the cleaning clamp 152 can be provided with elastic pads 1522 on the side close to each other, and meanwhile, the elastic pads 1522 can be provided with wrapping grooves matched with the glue dispensing needle.

[0066] Please refer to Figure 5 In addition, the cleaning mechanism 15 further comprises a counting inductor 158 and a no-material photoelectric inductor 159, the inductive end of the counting inductor 158 is connected with a guide roller 155, the no-material photoelectric inductor 159 is connected with the vertical fixing plate 151, and the transmitting part and the receiving part of the no-material photoelectric inductor 159 are located on the two sides of a section of the dust-free cloth 15B between the discharging roller 154 and the cleaning clamp 152.

[0067] The inductive function of the counting inductor 158 can control the movement of the dust-free cloth 15B by a set length each time, so as to ensure that a section of new and equal-length dust-free cloth 15B is used each time for cleaning. Meanwhile, the theoretical use times of a whole roll of the dust-free cloth 15B can be accurately counted, and a pre-warning can be given before the dust-free cloth 15B is about to be used up, so as to facilitate the operator to plan the replacement of the dust-free cloth 15B in the production gap and avoid emergency shutdown in the middle of production. The no-material inductor can monitor the state of the dust-free cloth 15B, so as to avoid the situation that the dust-free cloth 15B is not correctly threaded and deviated, i.e. the counting inductor 158 feeds back that the dust-free cloth 15B is being conveyed, but actually no dust-free cloth 15B is used for cleaning.

[0068] In the embodiment, the cleaning mechanism 15 further comprises a waste glue collecting cup 15A, which is arranged on the side of the vertical fixing plate 151 away from the cleaning clamp 152. When the glue dispensing needle is not used, the hot melt glue in the screw valve can be completely discharged into the waste glue collecting cup 15A, so as to prevent the solidification of the glue material and cause the glue dispensing needle to be unable to be used.

[0069] The glue dispensing device of the embodiment further comprises a hot melt glue preheater 17, which is located on one side of the glue dispensing head cleaning mechanism 15 and is used for preheating the hot melt glue in the glue dispensing needle.

[0070] The dispensing device of the embodiment further comprises a foreign matter collector 18 fixedly connected to one side of the cross beam 11, and two groups of dispensing mechanisms 12 are slidingly arranged on the cross beam 11, and the foreign matter collector 18 is located between the two groups of dispensing mechanisms 12.

[0071] The application also comprises a position correction method of a dispensing needle, which is controlled by a controller to correct the position of the dispensing needle of the high-precision dispensing device, and comprises the following steps: Step S11: The controller is preset with a dispensing coordinate system, the controller acquires preset position information of the dispensing needle and the correction point in the dispensing coordinate system, and controls the dispensing needle to move to the preset position of the correction point. The preset position information is equivalent to a preset virtual position of the dispensing needle and the correction point in the controller (it can be understood that the position of the dispensing needle is randomly moved), but the actual position of the dispensing needle and the correction point and the preset position information may deviate, so correction is needed.

[0072] Step S12: When the dispensing needle moves to the preset position of the correction point.

[0073] If the controller receives the sensing signal of the dispensing needle sent by the X-direction opposite sensor 142 and the Y-direction opposite sensor 143, it means that the actual position of the dispensing needle and the correction point and the preset position information do not deviate. Therefore, the X-direction data and the Y-direction data of the preset position of the correction point are taken as the X-direction data and the Y-direction data of the actual position.

[0074] If the controller does not receive the sensing signal of the dispensing needle sent by the X-direction opposite sensor 142 and the Y-direction opposite sensor 143, it means that the actual position of the dispensing needle and the correction point and the preset position information deviate. Then the controller controls the dispensing needle to move along the X-direction and / or the Y-direction until the sensing signal of the dispensing needle sent by the X-direction opposite sensor 142 and the Y-direction opposite sensor 143 is received, and the X-direction data and the Y-direction data of the position of the dispensing needle at this time are taken as the X-direction data and the Y-direction data of the actual position of the correction point. According to the X-direction data and the Y-direction data of the preset position and the actual position of the correction point, the XY-direction coordinate offset compensation amount is calculated, and the X-direction data and the Y-direction data of the preset position of the dispensing needle are updated to the X-direction data and the Y-direction data of the actual position according to the XY-direction coordinate offset compensation amount.

[0075] More specifically, if the controller does not receive the sensing signals of the X-direction opposite sensor 142 and the Y-direction opposite sensor 143 at the same time, the dispensing needle is controlled to move in a circular trajectory with the current position coordinate as the center and a set radius without changing the height of the Z axis.

[0076] If the X-direction photoelectric sensor 142 sends a sensing signal to the controller and the Y-direction photoelectric sensor 143 does not send a sensing signal to the controller during the movement along the circular trajectory, the movement of the dispensing needle head along the X-direction is continued until the dispensing needle head is sensed by the Y-direction photoelectric sensor 143, i.e. stopped, while the height of the Z-axis remains unchanged.

[0077] If the Y-direction photoelectric sensor 143 sends a sensing signal to the controller and the X-direction photoelectric sensor 142 does not send a sensing signal to the controller, the movement of the dispensing needle head along the Y-direction is controlled until the dispensing needle head is sensed by the X-direction photoelectric sensor 142, i.e. stopped, while the height of the Z-axis remains unchanged.

[0078] When the X-direction photoelectric sensor 142 and the Y-direction photoelectric sensor 143 both sense the dispensing needle head, i.e. stopped, the updating of the X-direction data and the Y-direction data of the actual position of the dispensing needle head and the compensation of the XY-direction coordinate offset can be calculated.

[0079] It is also necessary to mention that if the dispensing needle head moves along the circular trajectory for one full circle and is not sensed by the X-direction photoelectric sensor 142 or the Y-direction photoelectric sensor 143, the radius of movement is increased and the movement along the circular trajectory is performed again.

[0080] This step can realize the automatic positioning and offset compensation of the dispensing needle head in the XY direction, calculate the deviation between the theoretical position and the actual position, and automatically update the coordinate system parameters. This process is automatically completed and fast and efficient, without manual intervention or complex vision systems, which significantly improves the correction efficiency and accuracy.

[0081] Step S13: The sensing end of the Z-direction pressure sensor 144 is at a set distance from the calibration point. On the basis that the X-direction photoelectric sensor 142 and the Y-direction photoelectric sensor 143 both sense the dispensing needle head, the dispensing needle head is controlled to move downward along the Z-axis until the dispensing needle head contacts the sensing end of the Z-direction pressure sensor 144, and the downward movement is stopped when the Z-direction pressure sensor 144 senses a preset pressure value. The Z-direction coordinate offset compensation is calculated according to the Z-direction data of the sensing end of the Z-direction pressure sensor 144 and the Z-direction data of the preset position of the dispensing needle head. The Z-direction data of the preset position of the dispensing needle head is updated to the Z-direction data of the actual position according to the Z-direction coordinate offset compensation.

[0082] This step completes the accurate calibration of the dispensing needle head in the Z direction. On the premise that the horizontal position has been corrected, the accurate height of the needle tip is determined by the contact type pressure sensor. The preset pressure value is used as the stopping condition to avoid damage to the needle or the sensor due to excessive downward pressure. The Z-direction compensation obtained ensures the accuracy of the dispensing height and improves the dispensing precision and quality.

[0083] Step S14: During the process of the dispensing needle head descending along the Z direction, the X direction and Y direction photoelectric sensors 142 and 143 continuously sense the dispensing needle head, and if the controller does not receive the sensing signals of the X direction and Y direction photoelectric sensors 142 and 143 sensing the dispensing needle head, it is determined that the dispensing needle head has angular deflection and an alarm is issued.

[0084] This step increases the real-time dynamic monitoring function of the needle head posture. If the dispensing needle head is bent or tilted, it will deviate from the original horizontal sensing light beam during the downward process, resulting in signal loss. The system can immediately detect such abnormalities and issue an alarm, so that potential needle damage and tilt problems can be discovered in time to prevent dispensing precision and quality from being reduced due to poor needle posture.

[0085] The working principle of the present application is as follows: first, according to the shape and size specifications of the dispensing workpiece, a plurality of movable suction columns 19 or suction jigs 16 are arranged on the top surface of the transfer platform 13.

[0086] For standardized large quantities of workpieces, a dedicated suction jig 16 can be used. The jig plate body 161 is aligned and fastened with the positioning holes and connecting holes on the platform 13 through pins and screws, and the plurality of fixed suction columns 162 on the jig and the suction cups 1621 on the top of the fixed suction columns 162 constitute a fixed suction array.

[0087] For small batches, multiple varieties or special-shaped workpieces, a plurality of independent movable suction columns 19 are selected. These suction columns 19 are adsorbed on the top surface of the transfer platform 13 through the bottom magnet blocks, and can be arranged flexibly according to the workpiece profile. The plurality of rectangular block-shaped movable suction columns 19 can also be spliced through the connecting blocks 21 and the connecting grooves 22 to meet the demand for larger area suction.

[0088] Before dispensing, the needle position correction program needs to be executed. The controller controls the dispensing mechanism 12 to move the dispensing needle to the theoretical correction point preset position above the positioning mechanism 14 according to the preset dispensing coordinate system.

[0089] The X direction and Y direction photoelectric sensors 142 and 143 are integrated on the mounting frame 141 of the positioning mechanism 14, and their sensing paths intersect in the frame space. If the dispensing needle does not block the X direction and Y direction light beams at the same time, the controller will control the needle to move slightly in the XY plane until the sensing signals of the two sensors are triggered at the same time. At this time, the actual XY coordinates of the dispensing needle are recorded and compared with the theoretical value to calculate the XY coordinate offset compensation. According to the XY coordinate offset compensation, the X direction and Y direction data of the dispensing needle at the preset position are updated to the X direction and Y direction data at the actual position.

[0090] After the horizontal position correction is completed, the controller controls the dispensing needle to move downward along the Z direction.

[0091] The Z-direction pressure sensor 144 installed on the mounting plate 146 is located directly below the correction point. When the needle head contacts its sensing end and reaches the preset pressure value, the movement stops. At this time, the actual Z height of the needle tip is recorded, the Z coordinate offset compensation amount is calculated, and the Z direction data of the preset position of the dispensing needle head is updated to the actual position according to the Z coordinate offset compensation amount.

[0092] During the downward movement of the dispensing needle head in the Z direction, the X-direction and Y-direction opposite sensors 142 and 143 continue to work. If any sensor signal is lost at any stage of the downward movement, it indicates that the dispensing needle head has been bent or tilted, and the controller will issue an alarm to prompt the operator to check the needle head state.

[0093] After the workpiece is fixed and the dispensing needle head is corrected, the dispensing mechanism 12 and the transfer platform 13 can be moved relatively. The controller accurately controls the dispensing needle head to perform dispensing work on the workpiece surface according to the dispensing path program set and the coordinate data compensated and corrected.

[0094] After dispensing, the dispensing needle head needs to be cleaned. Otherwise, some glue will adhere to the needle head, causing the front end of the glue to be thicker, the glue width to be inconsistent, and affecting the dispensing quality and product yield of the next product. When cleaning, the controller controls the dispensing mechanism 12 to move the needle head above the cleaning mechanism 15.

[0095] The driving motor of the cleaning mechanism 15 is started, and through the cooperation of the material receiving roller 153, the guide roller 155 and the material discharging roller 154, a piece of dust-free cloth 15B is conveyed at a set length each time, so that a clean straight section 15B1 is in the working position. The length is accurately controlled by the counting sensor 158, and whether the dust-free cloth exists is monitored by the material opposite sensor 159.

[0096] The straight section 15B1 will first pass through the cloth pressing assembly 156, and the cooperation of the V-shaped block 15611 and the V-shaped groove 15621 makes the straight section preformed, and then the straight section passes between the two clamping blocks 1521 of the cleaning clamp 152, thereby forming a stable V-shaped cleaning cavity. In addition, the straight section 15B1 also passes through the V-shaped limiting groove 1573 of the guide plate 157 for further shaping and positioning.

[0097] The dispensing needle head drops into the V-shaped cavity formed by the lint-free cloth 15B. By clamping of the two clamping blocks 1521, the lint-free cloth 15B wraps the dispensing needle head, and can also cooperate with the up-down movement or stay of the dispensing needle head, to achieve effective wiping of the dispensing needle head. After cleaning, the two clamping blocks 1521 are opened, the dispensing needle head is lifted, the driving motor is actuated again, the used and dirty straight strip segment 15B1 is moved in the direction of the material collecting roller 153 and is wound up, and a new clean straight strip segment 15B1 is pulled to the working position, ready for the next cleaning.

[0098] The high-precision dispensing device of the preferred embodiment accurately acquires the horizontal position of the needle head through cross-sensing of the X-direction and Y-direction photoelectric sensors, and realizes high-precision correction of the three-dimensional space of the dispensing needle head through the Z-direction pressure sensor. The X-direction and Y-direction photoelectric sensors and the Z-direction pressure sensor are integrated on the same mounting frame, reducing installation cumulative error and improving the consistency of coordinate system calibration.

[0099] In the process of the dispensing needle head descending along the Z direction, the sensing signals of the X-direction and Y-direction photoelectric sensors are continuously monitored, so that it can be judged in real time whether the needle head has occurred to yaw or bending, and timely alarm is given, so as to avoid the decline of dispensing quality caused by abnormal needle head posture.

[0100] In summary, although the present application has been disclosed as above with preferred embodiments, the above preferred embodiments are not intended to limit the present application, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the protection scope of the present application is subject to the scope defined by the claims.

Claims

1. A high-precision dispensing device, characterized in that, include: Crossbeam, dispensing mechanism, transfer platform, positioning mechanism, and cleaning mechanism; The dispensing mechanism is slidably connected to the crossbeam, and the transfer platform is slidably disposed below the dispensing mechanism. The dispensing mechanism has mutually perpendicular X, Y and Z directions of movement relative to the transfer platform. The positioning mechanism is located on one side of the transfer platform and is used to correct the position of the dispensing needle of the dispensing mechanism. The cleaning mechanism is located below the trajectory of the dispensing mechanism and is used to clean the dispensing needle of the dispensing mechanism. The positioning mechanism includes a mounting frame, an X-axis through-beam sensor, a Y-axis through-beam sensor, and a Z-axis pressure sensor. The X-axis through-beam sensors are located on opposite sides of the mounting frame, and the Y-axis through-beam sensors are located on the other opposite sides of the mounting frame. The sensing paths of the X-axis and Y-axis through-beam sensors are located inside the mounting frame, and the sensing paths of the X-axis and Y-axis through-beam sensors intersect, with the intersection point serving as a calibration point. The Z-axis pressure sensor is located below the calibration point.

2. The high-precision dispensing device according to claim 1, characterized in that, Both the X-axis through-beam sensor and the Y-axis through-beam sensor include a transmitting component and a receiving component, and the transmitting component and the receiving component of the X-axis through-beam sensor and the Y-axis through-beam sensor are both disposed inside the mounting frame; The bottom of the mounting frame is connected to a mounting plate via a connecting rod, and the Z-axis pressure sensor is fixedly mounted on the mounting plate.

3. The high-precision dispensing device according to claim 1, characterized in that, The high-precision dispensing device also includes multiple adsorption columns. Each adsorption column has an airflow channel inside. The top of each adsorption column is provided with a suction cup that communicates with the airflow channel. One side of each adsorption column is provided with a connector that communicates with the airflow channel. The bottom of each adsorption column is provided with a magnet. The adsorption column is movably mounted on the top surface of the transfer platform via the magnet.

4. The high-precision dispensing device according to claim 3, characterized in that, The plurality of adsorption columns include cylindrical adsorption columns and rectangular block adsorption columns. The rectangular block adsorption columns have connecting blocks and connecting grooves on opposite sides, and two adsorption columns can be connected to each other through the connecting blocks and the connecting grooves. The connecting block includes protruding edge strips on both sides. The inner sides of the connecting groove are provided with slots for engaging with the protruding edge strips. The rectangular block-shaped adsorption column is also provided with an inlet groove on one side. The inlet groove is connected to the side of the connecting groove that is close to or away from the suction cup. The length and width of the inlet groove are greater than the length and width of the corresponding connecting block.

5. The high-precision dispensing device according to claim 1, characterized in that, The cleaning mechanism includes a vertical fixed plate, a drive motor, a lint-free cloth, a cleaning clamp, and a receiving roller, a discharging roller, and a guide roller that are rotatably mounted on one side of the vertical fixed plate. The receiving roller is connected to the output end of the drive motor. The lint-free cloth is wound around the receiving roller, the guide roller and the discharging roller in sequence. The lint-free cloth forms a straight strip between two of the guide rollers for cleaning the dispensing needle. The cleaning clamp is connected to the vertical fixing plate. The straight strip passes between the two clamping blocks of the cleaning clamp.

6. The high-precision dispensing device according to claim 5, characterized in that, The cleaning mechanism further includes a pressure cloth assembly. Along the moving direction of the cleanroom cloth, the pressure cloth assembly is located on one side of the cleaning clamp, and the pressure cloth assembly is located at the front end of the cleanroom cloth moving direction relative to the cleaning clamp. The pressure cloth assembly includes an upper pressure block and a lower pressure block. The top of the lower pressure block is provided with a V-shaped groove, and the bottom of the upper pressure block is provided with a V-shaped block corresponding to the V-shaped groove. The straight strip is inserted between the V-shaped block and the V-shaped groove so that when the cleaning clamp clamps the straight strip, the straight strip can form a V-shaped space for wrapping the dispensing needle.

7. The high-precision dispensing device according to claim 6, characterized in that, The cleaning mechanism also includes a guide plate connected to the vertical fixing plate. The top surface of the guide plate is provided with a limiting groove, which is a V-shaped structure. The straight strip passes through and is limited within the limiting groove. The cleaning clamp is located between the fabric pressing assembly and the guide plate.

8. The high-precision dispensing device according to claim 5, characterized in that, The cleaning mechanism also includes a counting sensor and a blanking sensor. The sensing end of the counting sensor is connected to one of the guide rollers, and the blanking sensor is connected to the vertical fixed plate. The transmitting and receiving components of the blanking sensor are located on both sides of a section of the cleanroom cloth between the feeding roller and the cleaning clamp.

9. The high-precision dispensing device according to claim 5, characterized in that, The cleaning mechanism also includes a waste glue collection cup, which is disposed on the side of the vertical fixing plate opposite to the cleaning clamp.

10. A method for calibrating the position of a dispensing needle, characterized in that, The high-precision dispensing device described in any one of claims 1-9 is controlled by a controller to perform dispensing needle position correction, comprising the following steps: Step S11: The controller has a preset dispensing coordinate system. The controller obtains the preset position information of the dispensing needle and the calibration point in the dispensing coordinate system, and controls the dispensing needle to move to the preset position of the calibration point. Step S12: If the controller receives the sensing signals from the X-axis through-beam sensor and the Y-axis through-beam sensor indicating that the dispensing needle has been detected, then the X-axis data and Y-axis data of the preset position of the calibration point are taken as the X-axis data and Y-axis data of the actual position. If the controller does not receive sensing signals from the X-axis and Y-axis through-beam sensors indicating that the dispensing needle has been detected, the controller controls the dispensing needle to move along the X and / or Y axes until sensing signals from the X-axis and Y-axis through-beam sensors indicating that the dispensing needle has been detected are received. The X-axis and Y-axis data of the current position of the dispensing needle are used as the actual X-axis and Y-axis data of the correction point. Based on the preset position of the correction point and the actual X-axis and Y-axis data, the XY-axis coordinate offset compensation is calculated. Based on the XY-axis coordinate offset compensation, the X-axis and Y-axis data of the preset position of the dispensing needle are updated to the actual X-axis and Y-axis data. Step S13: The sensing end of the Z-axis pressure sensor is a set distance away from the calibration point. Based on the fact that both the X-axis and Y-axis through-beam sensors have sensed the dispensing needle, the dispensing needle is controlled to descend along the Z-axis until it contacts the sensing end of the Z-axis pressure sensor. The descent stops when the Z-axis pressure sensor senses a preset pressure value. Based on the Z-axis data of the sensing end of the Z-axis pressure sensor and the Z-axis data of the preset position of the dispensing needle, the Z-axis coordinate offset compensation is calculated. Based on the Z-axis coordinate offset compensation, the Z-axis data of the preset position of the dispensing needle is updated to the Z-axis data of the actual position. Step S14: During the process of the dispensing needle descending along the Z direction, the X-direction through-beam sensor and the Y-direction through-beam sensor continuously sense the dispensing needle. If the controller does not receive the sensing signal from the X-direction through-beam sensor and the Y-direction through-beam sensor indicating that the dispensing needle has been sensed, it is determined that the dispensing needle has angular sway and an alarm is issued.

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