Automated production line for thermal printheads and manufacturing method of thermal printheads

Abstract

The application provides a thermal printing head automatic production line and a manufacturing method of the thermal printing head. The thermal printing head automatic production line comprises a carrier circulating in a circulation line. The circulation line comprises a heat sink assembly station, a rubber attaching station, a support assembly station, a first turnover station, a screwing station, a second turnover station, an attaching station and a pressure maintaining station. The production line comprises multiple devices. A heat sink feeding device places heat sinks into the carrier of the heat sink assembly station. A rubber attaching device attaches rubber to the heat sinks of the rubber attaching station. A support feeding device places supports into the carrier of the support assembly station. A first turnover device turns over the carrier of the first turnover station. A screwing device screws screws at the screwing station. A second turnover device turns over the carrier of the second turnover station. A thermal sheet feeding device attaches thermal sheets to the heat sinks of the attaching station. A pressure maintaining device performs pressure maintaining treatment on the pressure maintaining station. The application completes the assembly of the thermal printing head in full automation, improves the efficiency and the yield.

Description

Technical Field

[0001] This invention relates to the field of automated production technology, specifically to an automated production line for thermal printheads and a method for manufacturing thermal printheads. Background Technology

[0002] See Figure 1 The thermal printhead includes a thermal sheet 94, an FPC flexible circuit board (not shown in the figure), a metal heat sink 91, and two brackets 92. The two brackets 92 need to be fixed to both ends of the length of the metal heat sink 91 by screws 93. The thermal sheet 94 with the FPC flexible circuit board welded to it needs to be bonded to the first surface 911 of the metal heat sink 91 and pressed together. Then, UV glue needs to be applied and cured.

[0003] The assembly process of thermal printheads involves many steps and is complex. Full automation is now needed to improve efficiency and yield. Summary of the Invention

[0004] The primary objective of this invention is to provide a fully automated production line for thermal printhead assembly.

[0005] The second objective of this invention is to provide a method for manufacturing a thermal printhead that assembles the thermal printhead in a fully automated manner.

[0006] The automatic production line for thermal printheads provided by this invention includes a circulation line and carriers circulating at multiple stations on the circulation line. The multiple stations include, in sequence, a heat sink assembly station, an adhesive application station, a bracket assembly station, a first flipping station, a screw-driving station, a second flipping station, an attachment station, and a pressure holding station. The automatic production line for thermal printheads also includes a heat sink loading device, an adhesive application device, a bracket loading device, a first flipping device, a screw-driving device, a second flipping device, a thermal sheet loading device, and a pressure holding device. The heat sink loading equipment is used to place heat sinks into the carrier at the heat sink assembly station; the adhesive applicator is used to apply adhesive to the first surface of the heat sink at the adhesive applicator station; the bracket loading equipment is used to place brackets into the carrier at the bracket assembly station; the first flipping equipment is used to flip the carrier at the first flipping station; the screw-driving equipment is used to screw the heat sink and the bracket together from the opposite side of the first surface at the screw-driving station; the second flipping equipment is used to flip the carrier at the second flipping station; the thermistor loading equipment is used to attach the thermistor with the soldered flexible circuit board onto the first surface of the heat sink at the attaching station; and the pressure holding equipment is used to hold the pressure on the thermistor and the heat sink at the pressure holding station.

[0007] As can be seen from the above scheme, the present invention can automatically and sequentially complete the following processes: applying double-sided tape to the first surface of the heat sink, assembling the bracket, screwing the bracket, bonding the thermistor, pressurizing the thermistor and the heat sink, applying UV adhesive to the thermistor, and curing the adhesive. Firstly, the present invention considers the sequence of processes. Generally, component assembly is performed sequentially, with the required processes for assembling a component carried out continuously. For example, if the bracket assembly is performed before the thermistor assembly, the bracket placement and screwing are usually completed first, followed by applying adhesive to the heat sink and attaching the thermistor. However, the present invention adjusts the process sequence to make the overall line layout more rational. Both the heat sink and the bracket are fully automated for feeding. The two feeding machines occupy a large area, while the distance between adjacent workstations is small, leading to space constraints for both the heat sink feeding machine and the bracket feeding machine. Furthermore, the assembly of the thermistor involves higher precision requirements; if the thermistor assembly is performed first, it may be damaged during subsequent bracket assembly, resulting in defects. In summary, this invention chooses to interweave the bracket assembly process between the adhesive and attachment processes in the assembly of the thermal pad. Furthermore, this invention also considers the unique characteristics of bracket assembly. The bracket needs to be stacked onto the back side of the heat sink opposite the first surface, and screws are driven into that side. Generally, one would consider directly stacking the bracket onto the heat sink with the back side facing up and immediately continuing with the screwing process. However, considering the unique shape of the bracket, this invention cannot leave it in a flush, back-side-up position for the robotic arm to grasp during loading. Therefore, this invention prioritizes the success rate of bracket loading by picking up the flush, front-side-up bracket and moving it to one side of the heat sink with the first surface facing up, then pushing it horizontally under the heat sink, and finally flipping it over to perform the screwing process.

[0008] A further solution is that the multiple workstations also include a dispensing workstation and an adhesive curing workstation sequentially located downstream of the pressure holding workstation; the automated thermal printhead production line also includes dispensing equipment and adhesive curing equipment. The dispensing equipment is used to dispense adhesive between the thermal sheet and the heat sink in the dispensing workstation; the adhesive curing equipment is used to cure the adhesive between the thermal sheet and the heat sink in the adhesive curing workstation.

[0009] A further proposed solution includes multiple workstations, including a third flipping workstation, a laser marking workstation, and a fourth flipping workstation, sequentially located downstream of the adhesive curing workstation; the thermal printhead automated production line also includes a third flipping device, a laser marking device, and a fourth flipping device. The third flipping device is used to flip the carrier at the third flipping workstation; the laser marking device is used to perform laser marking on the heat sink and / or bracket at the laser marking workstation; and the fourth flipping device is used to flip the carrier at the fourth flipping workstation.

[0010] As can be seen from the above, based on the setting of the flip-over carrier, the carrier can be flipped over at the end, and laser marking can be completed on the back of the heat sink before flipping it back and waiting for the material to be discharged.

[0011] Another further option is that the multiple workstations also include a first visual inspection station located between the adhesive application station and the bracket assembly station, and the automatic thermal printhead production line also includes a first visual inspection device for visually inspecting the adhesive application status of the heat sink in the first visual inspection station; and / or, the multiple workstations also include a second visual inspection station located between the pressure holding station and the adhesive dispensing station, and the automatic thermal printhead production line also includes a second visual inspection device for visually inspecting the relative position of the pressure-held thermal sheet and the heat sink in the second visual inspection station.

[0012] As can be seen from the above, the assembly accuracy of the thermal sheet directly affects the function of the thermal printhead. Therefore, regarding the application accuracy of the double-sided adhesive, this invention uses a first vision inspection device to check whether the double-sided adhesive is flat and free of air bubbles. In addition, even if the positional accuracy is ensured when the thermal sheet is attached, the relative displacement between the thermal sheet and the heat sink may occur after the pressure is applied during the holding pressure process, thus affecting the attachment accuracy. Therefore, this invention uses a second vision inspection device to check the relative position between the feature points of the thermal sheet and the feature points of the heat sink or bracket after the holding pressure process is completed. If the situation does not meet the tolerance, it is judged as a defective product.

[0013] Another further solution is that the thermal sheet loading equipment includes a thermal sheet loading robot, a welding device, and an electrical conductivity testing device; the welding device is used to weld flexible circuit boards onto thermal sheets; the electrical conductivity testing device is used to perform electrical conductivity testing on the thermal sheets of the welded flexible circuit boards; the thermal sheet loading robot can move between the welding device, the electrical conductivity testing device, and the carrier at the attachment station.

[0014] As can be seen from the above, this setup integrates the welding of flexible circuit boards and thermal sheets into the automated production line, further improving the automation of product assembly. Furthermore, before the welding is completed and the product is sent to the bonding station, the flexible circuit boards and thermal sheets are powered on to perform functional tests, eliminating defects at the front end and avoiding subsequent waste of processes and other materials.

[0015] A further solution is that the automated thermal printhead production line also includes a third vision inspection device set at the attachment station. The third vision inspection device includes a third camera device and a fourth camera device. The third camera device is used to acquire first image data of the thermal sheet at the attachment station, and the third camera device is used to acquire second image data of the heat sink and / or bracket at the attachment station. The thermal sheet loading robot is used to attach the thermal sheet to the first surface of the heat sink based on the first image data and the second image data.

[0016] As can be seen from the above, the assembly accuracy of the thermal sheet directly affects the function of the thermal printhead. Furthermore, since the thermal sheet is directly attached to the flat first surface of the heat sink, it cannot rely on the structural features of the heat sink to reach its accurate position. Therefore, this invention considers using two sets of vision systems—a third camera and a fourth camera—to acquire feature points on the thermal sheet and on the heat sink or support. Through two imaging operations, the visual calculations confirm the relative position and distance between the thermal sheet and the heat sink. The vision system then transmits the data to the controller of the thermal sheet loading robot. The controller compares the data provided by the vision system with standard data and then controls the thermal sheet loading robot to correct the thermal sheet's deviation, rotate its angle, and move it a certain distance, ultimately placing the thermal sheet above the heat sink. Then, the fourth camera simultaneously photographs the thermistor and the heat sink or bracket, recalculating and confirming whether the relative position and distance between the thermistor and the heat sink are within the product's required dimensional tolerances. If they are, the thermistor is lowered for attachment; otherwise, the thermistor is further corrected and aligned until the relative position and distance between the thermistor and the heat sink are within the product's required attachment dimensional tolerances before attachment. After the thermistor is attached, the fourth camera simultaneously photographs the thermistor and the heat sink again, re-checking and calculating their relative distance and position to ensure they are within the product's required attachment tolerances and to ensure no defective products are attached.

[0017] Another further solution is that the support loading equipment includes a support transfer robot, a support loading robot, and two sets of support loading devices arranged opposite each other; the support loading device includes a support hopper, a flexible vibrating plate, and a linear vibrator, with the support hopper connected to the flexible vibrating plate; the support transfer robot is used to transfer the support from the flexible vibrating plate to the inlet of the linear vibrator; the support loading robot is used to transfer the support from the outlet of the linear vibrator to the carrier at the support assembly station.

[0018] As can be seen from the above, this invention takes into account the special shape of the bracket. During bracket loading, it's impossible to place the bracket with its back facing up and flat, waiting to be grasped by the robotic arm. Therefore, this invention prioritizes the success rate of bracket loading, picking up brackets with their front facing up and flat. However, a large portion of the brackets that fall from the hopper are in a tilted, bottom-up position, making it difficult for the robotic arm to grip them. To address this, this invention uses a flexible vibratory feeder to gently vibrate the brackets falling from the hopper. After vibration, all brackets will reach a horizontal, grippable position with their front facing up. A vertical vibrator then delivers the brackets one by one, ensuring the output brackets have accurate angles that require no further adjustment.

[0019] A further embodiment is that the bracket includes a bent connecting part and a protruding part, the heat sink includes a back side opposite to the first surface, and the connecting part is used to overlap and connect with the back side of the heat sink; the bracket loading robot grasps the protruding part when transferring the bracket; the carrier includes a bracket placement position and a floating limiting mechanism. In its natural state, the limiting mechanism restricts the bracket in the bracket placement position from the length direction of the heat sink; during the process of the bracket loading robot placing the bracket into the bracket placement position, it can force the limiting mechanism to float and release its limiting effect.

[0020] As can be seen from the above, placing the bracket face-up onto the carrier and then translating it to extend below the heat sink creates a new technical problem: in the space where the bracket needs to be translated, the carrier cannot restrict the brackets on both sides from the length direction of the thermal printhead. To address this, the present invention further improves the carrier by incorporating a floating limiting mechanism. In its natural state, the limiting mechanism restricts the bracket in its placement position from the length direction of the heat sink. During the bracket loading process, the robotic arm can force the limiting mechanism to float and release its limiting effect. Thus, the floating design of the limiting mechanism allows it to make way during bracket placement. Once the bracket is in place, the restored limiting mechanism can restrict the bracket from the length direction of the thermal printhead, preventing the bracket from becoming loose.

[0021] Another further solution is that the heat sink loading equipment includes a tray transport line, a heat sink transfer robot, a heat sink positioning mechanism, and a heat sink loading robot. The heat sink transfer robot is used to transfer the heat sink from the tray transport line to the heat sink positioning mechanism. The heat sink positioning mechanism is used to position the heat sink. The heat sink loading robot is used to transfer the heat sink from the heat sink positioning mechanism to the carrier at the heat sink assembly station. Furthermore, the heat sink loading robot, in cooperation with the heat sink positioning mechanism, can position the heat sink in the length, width, and height directions.

[0022] As can be seen from the above, in order to ensure the accuracy of the angle and level of the heat sink before it is placed into the carrier, the heat sink transfer robot first sends the heat sink to the heat sink positioning mechanism. The heat sink positioning mechanism can restrict the heat sink from the opposite sides in the width direction, the opposite sides in the length direction, and the bottom side. Meanwhile, the suction cup of the heat sink loading robot can restrict the heat sink from the top side. In this way, the horizontal angle and level of the heat sink are adjusted before the heat sink loading robot takes out the heat sink, thus improving the accuracy of subsequent processes.

[0023] Another further solution is that the multiple stations also include a finished product discharge station at the downstream end of the circulation line, which is set opposite to the heat sink assembly station along the width of the circulation line; the circulation line also includes a clamping device, which is set between the finished product discharge station and the heat sink assembly station; when the clamping device is working, it can simultaneously force the carrier of the heat sink assembly station and the carrier of the finished product discharge station to loosen their clamps.

[0024] As can be seen from the above, the carrier needs to be loosened when placing the heat sink plate and when removing the finished product. Since the heat sink plate loading station and the finished product unloading station are located at the beginning and end of the circulation line, respectively, and their positions are relatively close, this invention arranges them opposite each other on the circulation line, placing a single-powered loosening device between them. When the loosening device extends to push one carrier, it retracts and simultaneously pushes the other carrier. In this way, only a single linear drive unit is needed to simultaneously loosen and release the carriers on both sides, effectively reducing equipment costs.

[0025] The second objective of this invention is to provide a method for manufacturing a thermal printhead using an automated production line for thermal printheads according to any one of claims 1 to 10. The manufacturing method includes: placing a heat sink into a carrier at a heat sink assembly station; applying adhesive to the first surface of the heat sink at an adhesive application station; placing a bracket into a carrier at a bracket assembly station; flipping the carrier at a first flipping station; screwing the heat sink and the bracket together; flipping the carrier at a second flipping station; and attaching a thermally conductive sheet with a pre-welded flexible circuit board to the first surface of the heat sink at an attachment station.

[0026] As can be seen from the above solution, the present invention can automatically and sequentially complete the processes of applying double-sided tape to the first surface of the heat sink, assembling the bracket, screwing the bracket, and bonding the thermal pad. The present invention also considers the success rate of bracket loading, by picking up the bracket with its front side facing up and flush, moving it to one side of the heat sink with its first surface facing up, then pushing it horizontally under the heat sink, and then flipping it over to perform the screwing process. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a finished thermal printhead according to an embodiment of the automated production line for thermal printheads of the present invention.

[0028] Figure 2 This is a top view of an embodiment of the automated production line for thermal printheads of the present invention.

[0029] Figure 3 This is an isometric view of an embodiment of the automated production line for thermal printheads of the present invention.

[0030] Figure 4 This is a structural diagram of the heat sink positioning mechanism in an embodiment of the automated production line for thermal printheads of the present invention.

[0031] Figure 5 for Figure 3 Enlarged view of point A in the middle.

[0032] Figure 6 This is a schematic diagram showing the placement of the support onto the carrier in an embodiment of the automated production line for thermal printheads of the present invention.

[0033] Figure 7 This is a schematic diagram of the carrier being flipped in an embodiment of the automated production line for thermal printheads of the present invention.

[0034] Figure 8 This is a schematic diagram of screwing in an embodiment of the automatic production line for thermal printheads of the present invention.

[0035] Figure 9 This is a schematic diagram of attaching a thermal sheet in an embodiment of an automated production line for thermal printheads according to the present invention.

[0036] Figure 10 This is a schematic diagram of the third vision inspection device in an embodiment of the automated production line for thermal printheads of the present invention, which identifies the thermal sheet and the heat sink respectively.

[0037] Figure 11 This is a schematic diagram illustrating the relative position of the thermal sheet and the heat sink in the third visual inspection device of an embodiment of the automated production line for thermal printheads of the present invention.

[0038] Figure 12 for Figure 3 Enlarged view of point B in the middle.

[0039] Figure 13 This is a schematic diagram of the clamping device loosening and loosening two carriers in an embodiment of the automatic production line for thermal printheads of the present invention. Detailed Implementation

[0040] Example of an automated production line for thermal printheads

[0041] See Figure 2 and Figure 3 The automated production line for thermal printheads in this embodiment includes a circulation line and multiple carriers 8 that move between multiple stations on the circulation line. Figure 6 and Figure 7As shown in the diagram, the number of carriers 8 is consistent with the number of workstations, meaning that at any given processing time, a workpiece in one carrier 8 at each workstation is being operated by the equipment at that workstation. The multiple workstations include, in sequence: heat sink assembly workstation 101, adhesive application workstation 102, first visual inspection workstation 103, bracket assembly workstation 104, first flipping workstation 105, screw driving workstation 106, second flipping workstation 107, attachment workstation 108, pressure holding workstation 109, second visual inspection workstation 110, adhesive dispensing workstation 111, adhesive curing workstation 112, third flipping workstation 113, laser marking workstation 114, fourth flipping workstation 115, and finished product unloading workstation 116. On the cycle line, the distance between any two adjacent workstations is equal. The heat sink assembly workstation 101, as the first workstation, and the finished product unloading workstation 116, as the last workstation, are adjacent to each other because the cycle line connects end to end. The diagram shows that the x-axis represents the length of the loop line, and the y-axis represents the width of the loop line. Both the x-axis and y-axis are horizontal. Multiple workstations are arranged in rows along the length of the loop line, with each row containing 8 workstations. Multiple workstations are also arranged in columns along the width of the loop line, with each column containing 2 workstations.

[0042] The automated thermal printhead production line includes a heat sink loading device 201 corresponding to the heat sink assembly station 101. The heat sink loading device 201 includes a tray transport line 2011, a heat sink transfer robot 2012, a heat sink positioning mechanism 2013, and a heat sink loading robot 2014. The tray transport line 2011 uses a conveyor belt to transport stacked trays placed by the operator along a straight line to the picking position; the heat sink transfer robot 2012 is a three-axis robot, and its gripping part is a downward-facing negative pressure suction head; wherein, as... Figure 4 As shown, the heat sink positioning mechanism 2013 is a mechanism that can position the heat sink 91 from both sides in the width direction, both sides in the length direction, and the bottom side.

[0043] Among them, the heat sink loading robot 2014 is a gantry robot. The gripping part of the heat sink loading robot 2014 can move along the x-axis, y-axis, and z-axis. The gripping part of the heat sink loading robot 2014 is a negative pressure suction head set downwards. After the worker puts the stacked material trays into the material tray transport line 2011, the material tray transport line 2011 sends the stacked material trays in a straight line to the picking position. The heat sink transfer robot 2012 is used to transfer the heat sink from the material tray transport line 2011 to the heat sink positioning mechanism 2013. The heat sink loading robot 2014, in cooperation with the heat sink positioning mechanism 2013, can position the heat sink in the length, width, and height directions. The heat sink loading robot 2014 is used to transfer the heat sink from the heat sink positioning mechanism 2013 to the carrier 8 of the heat sink assembly station 101.

[0044] Combination Figure 4 The heat sink positioning mechanism 2013 includes a fixed base 37, a drive unit 36, a long-side positioning component 31, a wide-side positioning component 32, a linkage plate 33, and rollers 34. The long-side positioning component 31 is movably connected to the fixed base 37 along the y-axis via a first slide rail assembly, and the wide-side positioning component 32 is movably connected to the fixed base 37 along the x-axis via a second slide rail assembly. The fixed base 37 is provided with a positioning groove 30 for the heat sink 91. The fixed base 37 includes first baffles 351 disposed on opposite sides of the positioning groove 30 along the y-axis and the long-side positioning component 31, respectively. The fixed base 37 also includes second baffles 352 disposed on opposite sides of the positioning groove 30 along the x-axis and the wide-side positioning component 32, respectively.

[0045] The linkage plate 33 is fixedly connected to the long side positioning component 31, and the roller 34 is connected to the wide side positioning component 32. The linkage plate 33 is provided with a track groove 330 extending inclined in the x-axis direction. The roller 34 is located in the track groove 330 and the movement of the roller 34 is restricted by the track groove 330. Thus, when the drive unit 36 ​​drives the long side positioning component 31 to move along the y-axis direction and approach the positioning groove 30, the wide side positioning component 32 is also forced to move along the x-axis direction and approach the positioning groove 30 under the cooperation of the roller 34 and the track groove 330. Thus, after the heat sink 91 is placed into the positioning groove 30, a single drive unit can also achieve positioning in the x-axis direction and the y-axis direction.

[0046] In addition, the bottom of the positioning groove 30 supports the heat sink 91. During the process of the heat sink loading robot 2014 placing the heat sink 91 into the positioning groove 30, the negative pressure suction head of the heat sink loading robot 2014 and the bottom of the positioning groove 30 respectively position the heat sink 91 from the top and bottom sides. In this way, the heat sink loading robot 2014 and the heat sink positioning mechanism 2013 can position the heat sink 91 in the length, width and height directions.

[0047] See Figure 2 and Figure 3 The automated thermal printhead production line includes an adhesive application device 202 corresponding to the adhesive application station 102. The adhesive application device 202 is used to apply adhesive to the first surface 911 of the heat sink 91 of the adhesive application station 102. The adhesive application device 202 includes a double-sided adhesive masterbatch unwinding mechanism, a tensioning roller group, a take-up roll, a vertical movement mechanism, and a horizontal movement mechanism.

[0048] The automated production line for thermal printheads also includes a first vision inspection device 203 set up corresponding to the first vision inspection station 103. The first vision inspection device 203 includes a high-definition camera. The first vision inspection device 203 is used to visually inspect the adhesive application of the heat sink 91 in the first vision inspection station 103. The adhesive application includes the accuracy of the adhesive application position, the integrity of the adhesive application, and whether there are air bubbles.

[0049] See Figure 2 , Figure 3 as well as Figure 5 The automated thermal printhead production line includes a bracket loading device 204 corresponding to the bracket assembly station 104. The bracket loading device 204 includes a bracket transfer robot 2041, a bracket loading robot 2042, and two sets of bracket loading devices arranged opposite to each other. The bracket loading device includes a bracket hopper 2043, a flexible vibratory feeder 2044, and a linear vibrator 2045. Both the bracket transfer robot 2041 and the bracket loading robot 2042 are three-axis robots. The gripping parts of both the bracket transfer robot 2041 and the bracket loading robot 2042 include two grippers driven by pneumatic fingers.

[0050] The thermal printhead requires brackets 92 at both ends. Two bracket feeding devices are responsible for feeding the left and right brackets 92 respectively. The bracket hopper 2043 is connected to the flexible vibratory feeder 2044. The bracket transfer robot 2041 is used to transfer the brackets 92 from the flexible vibratory feeder 2044 to the inlet of the linear vibrator 2045. The bracket feeding robot 2042 is used to transfer the brackets 92 from the outlet of the linear vibrator 2045 to the carrier 8 of the bracket assembly station 104. In this embodiment, the transfer of the left and right brackets 92 is completed by the same bracket feeding robot 2042. In other embodiments, two bracket feeding robots 2042 can be set up on the left and right sides to transfer the brackets 92 on both sides simultaneously to improve efficiency.

[0051] Combination Figure 1 The bracket 92 includes a bent connecting portion 921 and a protruding portion 922. The heat sink 91 includes a back surface 912 opposite to the first surface 911. The connecting portion 921 is used to overlap with the back surface 912 of the heat sink. On the bracket 92, with the connecting portion 921 as the base, the protruding side of the protruding portion 922 is the front surface of the bracket 92, and the side of the connecting portion 921 with a flat surface, opposite to the protruding portion 922, is the bottom surface of the bracket 92. Because the bottom surface of the bracket 92 is flat, the bracket 92 can... Figure 1 The support 92 is temporarily positioned with its front facing upwards; however, if the bottom of the support 92 is facing upwards, it will tilt due to the presence of the protrusion 922.

[0052] If the support 92 is temporarily stored in a tilted position with its bottom surface facing upwards, the gripper of the support transfer robot 2041 cannot grasp the support 92 vertically downwards. If the gripper of the support transfer robot 2041 grasps the support 92 at an angle, the gripping part of the support transfer robot 2041 needs to have an additional degree of rotational freedom, and the angled gripping will also push the support 92 away, reducing the success rate of grasping. Conversely, when the support 92 is in a horizontal position with its front surface facing upwards, the upward-protruding part 922 becomes the gripping point of the gripper. Therefore, considering the special shape of the support 92, in order to improve the success rate of loading the support 92, the support transfer robot 2041 picks up the support 92 with its front surface facing upwards and flush during loading.

[0053] Furthermore, a large portion of the supports 92 that fall from the support hopper 2043 are in a tilted, bottom-up position, making it difficult for the support loading robot 2042 to pick them up. To address this, the present invention employs a flexible vibratory feeder 2044 to provide flexible vibration to the supports 92 that have fallen from the support hopper 2043. After vibration, all supports 92 will reach a horizontal, grippable position with their front faces upwards. A vertical vibrator 2045 then feeds the supports 92 out one by one, ensuring that the angle of the output supports 92 is accurate and requires no further adjustment.

[0054] See Figure 2 and Figure 6 To ensure effective positioning and restraint of the bracket 92, the carrier 8 includes a bracket placement position 890 and a limiting mechanism 81. The limiting mechanism 81 is used to restrain the bracket 92 in the bracket placement position 890 from the length direction of the heat sink (x-axis direction in the figure). However, the bent bracket 92 needs to be moved downward along the Z-axis with its front facing up to one side of the heat sink 91 until the connecting part 921 reaches below the position of the heat sink 91, and then translated along the x-axis to make the connecting part 921 overlap with the back side 912 of the heat sink 91.

[0055] To avoid interference between the limiting mechanism 81 and the movement of the bracket 92, the present invention configures the limiting mechanism 81 as a floating structure. Specifically, the limiting mechanism 81 is configured to be able to swing around the axis 800, and the limiting mechanism 81 is connected to the fixed part of the carrier 8 by a spring. In this way, under the restoring force of the spring, the limiting mechanism 81 remains in a fixed position. Figure 6 The upper limit position of state a is also the natural state of this invention. When the limiting mechanism 81 is pressed down, it swings downwards. Figure 6 In state b, the limiting mechanism 81 is in the lower limit position, at which point the spring stores energy.

[0056] During the process of the support loading robot 2042 placing the support 92 into the support placement position 890, it passes through the support in sequence. Figure 6 The states are shown in state diagrams a, b, and c. Figure 6As shown in state diagrams a and b, during the process of the support loading robot 2042 placing the support 92 into the support placement position 890, the support 92, during its downward movement, abuts against the limiting mechanism 81 and forces the limiting mechanism 81 to swing down to its lower limit position, thereby releasing the limiting mechanism 81 from its limiting effect in the x-axis direction, achieving the avoidance effect. Figure 6 As shown in state diagrams b and c, after the bracket 92 translates along the x-axis and fully reaches the bracket placement position 890, the limiting mechanism 81 rebounds under the restoring force of the spring and swings back to its natural state, thus restricting the bracket 92 from the x-axis direction.

[0057] See Figure 2 and Figure 7 The automated thermal printhead production line includes a first flipping device 205 corresponding to the first flipping station 105. The first flipping device 205 is used to flip the carrier 8 of the first flipping station 105. The first flipping device 205 can engage and disengage with the carrier 82. After engaging with the carrier 82, the first flipping device 205 can drive the carrier 82 to flip.

[0058] like Figure 6 As shown in the diagram, after the bracket 92 is placed, the connecting part 921 is located below the heat sink 91, and the first surface 911 is still facing upwards. Since screwing needs to be done from the side where the connecting part 921 is located, the carrier 8 of this invention is provided with a bearing part 82 that can be rotated along the x-axis. The bearing part 82 is provided with a fixing mechanism 821 that fixes the heat sink 91 from the y-axis direction to ensure that the heat sink 91 does not fall off during and after the bearing part 82 is rotated. Figure 6 As shown in the state diagram, after the support part 82 is flipped, the connecting part 921 is located above the heat sink 911.

[0059] Combination Figure 2 and Figure 8 The automated production line for thermal printheads includes a screw-driving device 206 corresponding to the screw-driving station 106. The screw-driving device 206 includes an electric screwdriver and is used to drive screws 93 into the bracket 92 and the heat sink 91 from top to bottom at the screw-driving station 106, from the opposite side of the first surface 911, i.e., the side where the connecting part 921 is located.

[0060] See Figure 2 The thermal printhead automated production line includes a second flipping device 207 corresponding to the second flipping station 107, which is used to flip the carrier 8 of the second flipping station 107 again.

[0061] See Figure 2 , Figure 3 as well as Figures 9 to 11The automated thermal printhead production line includes a thermal sheet loading device 208 and a third-vision inspection device 2080, respectively, located at the bonding station 108. The thermal sheet loading device 208 includes a thermal sheet loading robot 2081, a welding device 2082, and a power-on detection device 2083. The welding device 2082 is used to weld flexible circuit boards onto thermal sheets 94; the power-on detection device 2083 is used to perform power-on detection on the thermal sheets 94 with welded flexible circuit boards. The thermal sheet loading robot 2081 is a three-axis robot, and it can move between the welding device, the power-on detection device, and the carrier 8 at the bonding station 108.

[0062] The thermal sheet loading robot 2081 can transfer the thermal sheet 94, which has completed welding and power-on testing, to the attachment station 108. Figure 10 This is a diagram from a top-down perspective. Figure 10 The image is illustrated by two dashed boxes, which respectively indicate the imaging range of the third camera device 2084 and the fourth camera device 2085. Before attaching the thermal sheet 94 to the first surface 911, visual inspection and correction processing are required. The visual inspection is performed by the third visual inspection device 2080. The third visual inspection device 2080 includes the third camera device 2084 and the fourth camera device 2085; the third camera device 2084 is used to acquire the first image data of the thermal sheet 94 at the attachment station 108, and the third camera device 2085 is used to acquire the second image data of the heat sink 91 at the attachment station 108.

[0063] This invention uses two sets of vision systems, a third camera device 2084 and a fourth camera device 2085, to acquire feature points on the thermal sheet 94 and the heat sink 91. By taking two pictures, the visual calculation confirms the relative position and distance between the thermal sheet 94 and the heat sink 91. Then, the vision system transmits the data to the controller of the thermal sheet loading robot 2081. The controller compares the data provided by the vision system with standard data, and then controls the thermal sheet loading robot 2081 to correct the deviation, rotate the angle and move the distance of the thermal sheet 94, so as to move the thermal sheet 94 above the heat sink 91. Then, the fourth camera device 2085 simultaneously takes pictures of the thermal pad 94 and the heat sink 91, and recalculates to confirm whether the relative position and distance between the thermal pad 94 and the heat sink 91 are within the dimensional tolerance required by the product. If they are, the device is lowered for attachment; if not, the thermal pad 94 is further corrected and aligned until the relative position and distance between the thermal pad 94 and the heat sink 91 are within the attachment dimensional tolerance required by the product before attachment. The relative position and distance between the thermal pad 94 and the heat sink 91 can be calculated based on the feature point coordinates of the first image data and the feature point coordinates of the second image data. For example, the feature point in the first image data is the endpoint of line 941 where the thermal element on the thermal pad 94 is located, and the system uses the feature point in the second image data as the edge of the heat sink 91. The actual distance n between line 941 and the edge of the heat sink 91 in the x-axis direction determines the tolerance from the preset distance.

[0064] After the thermal pad 94 is attached, the fourth camera device 2085 takes pictures of the thermal pad 94 and the heat sink 91 simultaneously again, and re-checks and calculates the relative distance and position of the thermal pad 94 and the heat sink 91 to ensure that the product is attached within the required attachment tolerance range and that there are no defective products.

[0065] See Figure 2 The automated thermal printhead production line includes a pressure holding device 209 corresponding to the pressure holding station 109. The pressure holding device 209 is used to maintain pressure on the thermal sheet 94 and the heat sink 91 in the pressure holding station 109. The pressure holding device 209 mainly includes a pressure head with pressure detection and buffering. The pressure head presses down on the thermal sheet 94 to provide pressure holding pressure.

[0066] See Figure 2 , Figure 3 and Figure 12The automated production line for thermal printheads includes a second vision inspection device 210 corresponding to the second vision inspection station 110. The second vision inspection device 210 is used to visually inspect the relative position of the thermal sheet 94 and the heat sink 91 after pressure holding in the second vision inspection station 110. During the pressure holding process, the pressure applied may cause relative displacement between the thermal sheet 94 and the heat sink 91, affecting the bonding accuracy. Therefore, this invention uses the second vision inspection device 210 to inspect the relative position between the feature points of the thermal sheet 94 and the feature points of the heat sink 91 after the pressure holding process is completed. If the position does not meet the tolerance, it is judged as a defective product.

[0067] See Figure 2 The automated thermal printhead production line includes a dispensing device 211 corresponding to the dispensing station 111 and an adhesive curing device 212 corresponding to the adhesive curing station 112. The dispensing station 111 and adhesive curing station 112 are further included. The dispensing device 211 is used to apply UV adhesive to the surrounding seams between the thermal sheet 94 and the heat sink 91 in the dispensing station 111. The adhesive curing device 212 is used to perform UV adhesive irradiation curing on the thermal sheet 94 and the heat sink 91 in the adhesive curing station 112.

[0068] See Figure 2 The thermal printhead automatic production line includes a third flipping station 113, a laser marking station 114, and a fourth flipping station 115, respectively. The thermal printhead automatic production line also includes a third flipping device 213, a laser marking device 214, and a fourth flipping device 215. The third flipping device 213 is used to flip the carrier 8 of the third flipping station 113. The laser marking device 214 is used to perform laser marking on the back side 912 of the heat sink 91 of the laser marking station 114. The fourth flipping device 215 is used to flip the carrier 8 of the fourth flipping station 115 again.

[0069] See Figure 2 The automated thermal printhead production line includes an unloading device 216 corresponding to the finished product unloading station 116. The unloading device 216 includes an unloading robot 2161, a qualified product placement station 2162, and a defective product placement station 2163. The gripping part of the unloading robot 2161 can move between the unloading station 116 and the qualified product placement station 2162, and can also move between the unloading station 116 and the defective product placement station 2163. If any station produces a defective product, the subsequent stations stop processing the defective product, and finally, the unloading robot 2161 transfers it to the defective product placement station 2163.

[0070] See Figure 2 and combined Figure 13The finished product discharge station 116 and the heat sink assembly station 101 are arranged opposite each other along the width direction of the circulation line (the y-axis direction in the figure). The circulation line also includes a clamping device 218, which is located between the finished product discharge station 116 and the heat sink assembly station 101. The clamping device 218 includes a cylinder, the cylinder body 2182 of which is slidably connected to the fixed part 2181 along the width direction of the circulation line via a slide rail assembly, and a tension spring is connected between the cylinder body 2182 and the fixed part 2181. Two pushing parts 2189 are connected to the cylinder rod 2182 and the piston rod end 2183, and the two pushing parts 2189 extend opposite each other along the width direction of the circulation line.

[0071] When the cylinder operates, the piston rod end 2183 advances until the pushing component 2189 on it abuts against a carrier 8. Since the piston rod end 2183 is blocked from advancing and the piston rod end 2183 has not reached its extension limit, the sliding cylinder 2182 is forced to advance in the opposite direction until the pushing component 2189 on it abuts against another carrier 8. In this way, when the loosening device 218 is working, it can simultaneously force the carrier 8 at the heat sink assembly station and the carrier 8 at the finished product discharge station 116 to loosen.

[0072] This invention automates the assembly of thermal printheads, improving assembly efficiency and yield.

[0073] In this process, both the heat sink and the bracket are fully automated for feeding. The two feeding machines occupy a significant amount of space, while the distance between adjacent workstations is small, leading to space constraints for the heat sink feeding machine 201 and the bracket feeding machine 204. Furthermore, the assembly of the thermal pads involves higher precision requirements. If the thermal pads are assembled first, they may be damaged during subsequent bracket assembly, resulting in defects. Therefore, this invention optimizes the process sequence by interleaving the bracket assembly process between the adhesive and bonding processes in the thermal pad assembly.

[0074] In addition, the present invention takes into account the special shape of the bracket. When the bracket is loaded, it is not possible to wait for the robot to pick it up with the back facing up and flat. Therefore, the present invention takes into account the success rate of bracket loading. The bracket with the front facing up and flat is picked up and moved to the side of the heat sink plate with the first surface 911 facing up, and then pushed into the bottom of the heat sink plate. Then it is flipped over to perform the screwing process.

[0075] In addition, this invention takes into account the characteristic of the continuous circulation line, where the first station and the last station are adjacent and close to each other. The first station and the last station are the loading station and the unloading station, respectively, both of which require the carrier to be released and released. Therefore, a release and release device that can release and release the two carriers simultaneously with a single power source is set between the first station and the last station, making the production line layout more compact and reducing equipment costs.

[0076] Example of a method for manufacturing a thermal printhead

[0077] See Figures 1 to 3 In the method for manufacturing a thermal printhead, the thermal printhead is manufactured using the automated production line for thermal printheads of the present invention.

[0078] The manufacturing method of a thermal printhead includes the following steps:

[0079] The control robot 2014 transfers the heat sink from the heat sink positioning mechanism 2013 to the carrier 8 of the heat sink assembly station 101.

[0080] The adhesive application equipment 202 applies adhesive to the first surface 911 of the heat sink 91 at the adhesive application station 102.

[0081] The first vision inspection device 203 is controlled to perform visual inspection on the adhesive application of the heat sink 91 in the first vision inspection station 103. The adhesive application status includes the accuracy of the adhesive application position, the integrity of the adhesive application, and whether there are air bubbles.

[0082] The control support loading robot 2042 moves the support 92 from the outlet of the vibrator 2045 to the carrier 8 of the support assembly station 104.

[0083] The first flipping device 205 is controlled to flip the carrier 8 of the first flipping station 105.

[0084] The screw-driving device 206 drives the screws 93 into the bracket 92 and the heat sink 91 from top to bottom at the screw-driving station 106, from the opposite side of the first surface 911, that is, the side where the connecting part 921 is located.

[0085] The second flipping device 207 is controlled to flip the carrier 8 of the second flipping station 107 again.

[0086] The control robot 2081 for loading thermal sheet moves between the welding equipment, the power-on testing equipment and the carrier 8 of the attachment station 108 and attaches the thermal sheet 94 to the first surface 911. Before attaching the thermal sheet 94 to the first surface 911, visual inspection and correction processing are required. The visual inspection is performed by the third visual inspection device 2080.

[0087] During the correction process, the control robot 2081 for loading the thermal sheet 94 corrects its deviation, rotates it, and moves it a certain distance, thus moving the thermal sheet 94 above the heat sink 91.

[0088] After the thermal pad 94 is attached, the fourth camera device 2085 is controlled to take pictures of the thermal pad 94 and the heat sink 91 simultaneously again, and the relative distance and position of the thermal pad 94 and the heat sink 91 are re-checked and calculated to ensure that the attachment is within the required tolerance range and that there are no defective products.

[0089] Subsequently, the pressure holding device 209 controls the pressure holding process of the thermistor 94 and the heat sink 91 in the pressure holding station 109.

[0090] Then, the second vision inspection device 210 is controlled to perform visual inspection on the relative position of the pressure-holding thermal sheet 94 and the heat sink 91 in the second vision inspection station 110.

[0091] Next, the dispensing equipment 211 controls the UV adhesive to be applied to the four-sided connection seam between the thermal sheet 94 and the heat sink 91 in the dispensing station 111, and then the adhesive curing equipment 212 controls the UV adhesive to be applied to the thermal sheet 94 and the heat sink 91 in the adhesive curing station 112 for curing.

[0092] Then, the third flipping device 213 is controlled to flip the carrier 8 of the third flipping station 113, and the laser marking device 214 is controlled to perform laser marking on the back 912 of the heat sink 91 of the laser marking station 114. Then, the fourth flipping device 215 is controlled to flip the carrier 8 of the fourth flipping station 115 again.

[0093] Finally, the gripping part of the unloading robot 2161 is controlled to move between the unloading station 116 and the qualified product placement station 2162 to send out qualified workpieces, or the unloading robot 2161 is controlled to move between the unloading station 116 and the defective product placement station 2163 to recover defective products.

[0094] Finally, it should be emphasized that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A thermal printhead automated production line, characterized by, Comprising: a circulation line and a carrier circulating on a plurality of stations of the circulation line, the plurality of stations comprising, in sequence, a heat sink assembling station, a rubberizing station, a bracket assembling station, a first overturning station, a screwing station, a second overturning station, an attaching station and a pressure maintaining station; The thermal print head automatic production line further comprises: a heat sink loading device for placing a heat sink into the carrier of the heat sink assembling station; a rubberizing device for rubberizing a first surface of the heat sink at the rubberizing station; a bracket loading device for placing a bracket into the carrier of the bracket assembling station; a first overturning device for overturning the carrier at the first overturning station; a screwing device for screwing the heat sink and the bracket from the opposite side of the first surface at the screwing station; a second overturning device for overturning the carrier at the second overturning station; a thermal sheet loading device for attaching a thermal sheet of a flexible circuit board that has been welded to the first surface of the heat sink at the attaching station; a pressure maintaining device for pressure maintaining the thermal sheet and the heat sink at the pressure maintaining station; The plurality of stations further comprises, in sequence, a dispensing station and a glue curing station downstream of the pressure maintaining station; The thermal print head automatic production line further comprises: a dispensing device for dispensing between the thermal sheet and the heat sink at the dispensing station; a glue curing device for glue curing the thermal sheet and the heat sink at the glue curing station.

2. The thermal print head automatic production line according to claim 1, wherein: The plurality of stations further comprises, in sequence, a third overturning station, a laser code printing station and a fourth overturning station downstream of the glue curing station; The thermal print head automatic production line further comprises: a third overturning device for overturning the carrier at the third overturning station; a laser code printing device for laser code printing the heat sink and / or the bracket at the laser code printing station; a fourth overturning device for overturning the carrier at the fourth overturning station.

3. The thermal print head automatic production line according to claim 1, wherein: The plurality of stations further comprises a first visual inspection station arranged between the rubberizing station and the bracket assembling station, and the thermal print head automatic production line further comprises a first visual inspection device for visually inspecting the rubberizing of the heat sink at the first visual inspection station; and / or The plurality of stations further comprises a second visual inspection station arranged between the pressure maintaining station and the dispensing station, and the thermal print head automatic production line further comprises a second visual inspection device for visually inspecting the relative position of the pressure maintained thermal sheet and the heat sink at the second visual inspection station.

4. The thermal print head automatic production line according to claim 3, wherein: The thermal sheet loading device comprises a thermal sheet loading robot, a welding device and a power-on detection device. ​ The welding device is used for welding the flexible circuit board to the thermosensitive sheet; The power-on detection device is used for power-on detection of the thermosensitive sheet of the welded flexible circuit board; The thermosensitive sheet loading manipulator is movable between the welding device, the power-on detection device and the carrier of the attaching station.

5. The automatic production line of the thermal print head according to claim 4, wherein: The automatic production line of the thermal print head further comprises a third visual detection device arranged at the attaching station, and the third visual detection device comprises a third camera and a fourth camera; The third camera is used for acquiring first image data of the thermosensitive sheet of the attaching station, the fourth camera is used for acquiring second image data of the heat dissipation plate and / or the bracket of the attaching station, and the thermosensitive sheet loading manipulator is used for attaching the thermosensitive sheet to the first surface of the heat dissipation plate according to the first image data and the second image data.

6. The automatic production line of the thermal print head according to any one of claims 1 to 5, wherein: The bracket loading device comprises a bracket transfer manipulator, a bracket loading manipulator and two groups of bracket loading devices arranged oppositely; The bracket loading device comprises a bracket warehouse and a flexible vibrating disc in communication, and a straight vibrator; The bracket transfer manipulator is used for transferring the bracket from the flexible vibrating disc to the inlet of the straight vibrator; The bracket loading manipulator is used for transferring the bracket from the outlet of the straight vibrator to the carrier of the bracket assembling station.

7. The automatic production line of the thermal print head according to claim 6, wherein: The bracket comprises a connecting portion and a protruding portion connected by bending, and the heat dissipation plate comprises a back surface opposite to the first surface, and the connecting portion is used for being overlapped and connected with the back surface of the heat dissipation plate; The bracket loading manipulator grasps the protruding portion when transferring the bracket; The carrier comprises a bracket placement position and a floating limiting mechanism, and in a natural state, the limiting mechanism limits the bracket in the bracket placement position from the length direction of the heat dissipation plate; The bracket loading manipulator can force the limiting mechanism to float and release the limiting action in the process of placing the bracket into the bracket placement position.

8. The automatic production line of the thermal print head according to any one of claims 1 to 5, wherein: The heat dissipation plate loading device comprises a tray conveying line, a heat dissipation plate transfer manipulator, a heat dissipation plate positioning mechanism and a heat dissipation plate loading manipulator, the heat dissipation plate transfer manipulator is used for transferring the heat dissipation plate from the tray conveying line to the heat dissipation plate positioning mechanism, the heat dissipation plate positioning mechanism is used for positioning the heat dissipation plate, the heat dissipation plate loading manipulator is used for transferring the heat dissipation plate from the heat dissipation plate positioning mechanism to the carrier of the heat dissipation plate assembling station, and the heat dissipation plate loading manipulator and the heat dissipation plate positioning mechanism cooperate to position the heat dissipation plate from the length direction, the width direction and the height direction of the heat dissipation plate.

9. The automatic production line of the thermal print head according to any one of claims 1 to 5, wherein: The plurality of stations further comprise a finished product discharge station at the most downstream end of the circulation line, the finished product discharge station being arranged opposite the heat sink assembly station along the width direction of the circulation line; The circulation line further comprises a loose clamping device arranged between the finished product discharge station and the heat sink assembly station; The loose clamping device is capable of simultaneously forcing the carrier of the heat sink assembly station and the carrier of the finished product discharge station to loosen clamping.

10. A method of manufacturing a thermal printhead, characterized by: manufacturing the thermal printhead by means of the automatic production line of the thermal printhead according to any one of claims 1 to 9; the manufacturing method comprising: placing a heat sink into the carrier of the heat sink assembly station; applying adhesive to the first surface of the heat sink at the adhesive application station; placing a bracket into the carrier of the bracket assembly station; turning over the carrier of the first turning-over station; screwing between the heat sink and the bracket; turning over the carrier of the second turning-over station; attaching a thermal sheet with a flexible circuit board welded thereto to the first surface of the heat sink at the attachment station.

11. A thermal printhead manufactured by the method of claim 10.

Images