soldering equipment

Abstract

To provide a soldering device that includes an arm capable of canceling thermal elongation and controls a position, a speed, and a posture.SOLUTION: A soldering device includes: first suction means that sucks an upper surface of a work piece by air to float the work piece; a heating head 11 having the first suction means and a temperature sensor capable of adjusting a temperature of the work piece and which can be raised and lowered until it contacts the upper surface of the work piece; a first drive unit that drives the heating head 11 such that the heating head is moved upward / downward; and an adjusting mechanism 40 that causes an upward movement operation of the heating head 11 in a direction opposite to a thermal elongation direction of the heating head 11. By providing the adjusting mechanism 40 that makes a positional adjustment to the heating head, resulting from thermal elongation of an arm supporting the heating head 11, thickness of a solder layer is controlled when the work piece is jointed to a target object through solder. Thus, position, speed and posture are controlled during assembly, and soldering quality can be improved.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a soldering device having a mechanism for correcting the position of a heating head. [Background technology]

[0002] Conventionally, electronic components are heated while being pressed against a workpiece to heat the electronic components. Crimping devices are known.

[0003] The sleeve soldering device of Patent Document 1 includes a sleeve that supplies solder, a heater that heats the sleeve, a movement mechanism that moves the sleeve, a detection unit, and a determination unit. The numerical control device of Patent Document 2 has a thermal displacement correction function, and is provided with a thermal correction data storage means, a correction program analysis means, a correction program determination means, and a correction data correction means. Conventionally, there has been no known soldering machine that is equipped with an arm that performs compensation to reduce thermal displacement and that controls the position, speed, and attitude of the heating head during assembly. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-850 [Patent Document 2] Japanese Patent Publication No. 2020-188204 Summary of the Invention [Problem to be solved by the invention]

[0005] Causes of solder overflow caused by excessively pressing the emitter during assembly include teaching errors, loose equipment components, or thermal expansion of the head, etc. This invention solves the problems associated with thermal expansion and contraction of the head during the process from the temperature rise step to the temperature drop step during soldering.

[0006] In solder assembly with a heating structure, the assembly arm expands due to heat, and there is a difference in the amount of thermal expansion, for example, about 0.28 mm, before and after the temperature rises. In soldering equipment that requires high-precision assembly, for example ±0.05 mm, it takes a long time for the entire equipment to heat up, and if there is a period of downtime, it takes a long time to restart.If the equipment is temporarily stopped, it takes a long time to restart, and if the heater is turned off, it takes a further long time to restart, resulting in a large loss of time.

[0007] The present invention has been made in view of the above, and an object of the present invention is to provide a soldering machine that is equipped with an arm that can cancel thermal expansion and that controls the position, speed, and attitude. [Means for solving the problem]

[0008] The soldering device of the present invention is a soldering device that applies solder (2) to the top surface of an object (3) to be joined, and then lowers a work (1) from above the solder to join the work to the object via the solder, and includes first suction means (25, 27) that sucks the top surface of the work with air to lift the work, said first suction means and a heating head (11) that has a temperature sensor that can adjust the temperature of the work and can move up and down until it abuts on the top surface of the work, a first drive unit (28) that drives the heating head so that it can be raised and lowered up and down, and a first drive unit (28) that can operate independently of said first suction means and that sucks the top surface of the work with air to lift the work. a cooling head (31) having the second suction means and a cooling device capable of cooling the workpiece, operable independently of the heating head and capable of moving up and down until it abuts on the top surface of the workpiece; a second drive unit (29) for driving the cooling head so that it can move up and down; a heater provided in the heating head for heating the heating head; an adjustment mechanism (40) for creating an upward movement due to a thermal expansion difference of the heating head; and a control device (100) for outputting a command value for controlling the positions of the heating head and the cooling head to the first drive unit and the second drive unit.

[0009] According to the present invention, the operation of the heating head for heating the workpiece and the operation of the cooling head for cooling the workpiece are independent, and the workpiece is cooled and cooled without being affected by the heat of the heating head. At this time, the switching speed from workpiece heating to workpiece cooling can be performed in a short time. The thermal efficiency in raising and lowering the temperature of the workpiece is good. Furthermore, by providing an adjustment mechanism that adjusts the position of the heating head in the direction opposite to the thermal extension direction of the arm that raises and lowers the heating head, the thickness of the solder layer is controlled when joining the workpiece to the object to be joined via solder, and excess solder is absorbed by a fillet. This makes it possible to control the position, speed, and posture during assembly and improve soldering quality. [Brief explanation of the drawings]

[0010] [Figure 1] 5A and 5B are schematic diagrams for explaining the control of the thickness of a solder layer by the soldering apparatus of the first embodiment. [Figure 2] 1 is a schematic diagram showing the mechanism of a soldering apparatus according to a first embodiment and a second embodiment; [Figure 3] FIG. 2 is a partially enlarged view showing the mechanism of the soldering apparatus according to the first and second embodiments. [Figure 4] FIG. 2 is a partially enlarged view showing the mechanism of the soldering device of the first embodiment. [Figure 5] FIG. 4 is a schematic cross-sectional view illustrating the operation of the first embodiment. [Figure 6] FIG. 4 is a schematic cross-sectional view illustrating the operation of the first embodiment. [Figure 7] FIG. 6 is a partially enlarged view showing the mechanism of a soldering device according to a second embodiment. [Figure 8] FIG. 10 is a schematic configuration diagram of a soldering device according to a third embodiment. [Figure 9] 5A and 5B are schematic cross-sectional views illustrating the operation of a soldering device of a comparative example. [Figure 10] FIG. 10 is a characteristic diagram showing the measurement results of the expansion amount of the heating head of a soldering device of a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, soldering devices according to several embodiments will be described with reference to the drawings. Note that substantially the same components in several embodiments are designated by the same reference numerals, and descriptions thereof will be omitted.

[0012] (First embodiment) A first embodiment of the present invention will be described with reference to FIGS.

[0013] 1, an example will be described in which a workpiece 1 as an emitter is joined to the collector 5 side. In this case, a semiconductor element 4 and a spacer 3 as an object to be joined are layered in this order on the upper surface of the collector 5, and the workpiece 1 is soldered to the spacer 3.

[0014] A semiconductor element 4 corresponding to the object to be bonded and a spacer 3 corresponding to the object to be bonded are formed in this order in a layer structure on the upper surface of a collector 5 corresponding to the object to be bonded, and an emitter 1 corresponding to the workpiece is conveyed above the spacer 3 and lowered, and the emitter 1 is solder-bonded to the upper surface of the spacer 3 via solder 2.

[0015] The workpiece 1 in the state before soldering shown in Figure 1(A) is transformed into the workpiece 1 in the state after soldering shown in Figure 1(B) by the soldering device 10 adjusting or controlling the solder layer thickness d shown in Figure 1(B).

[0016] The soldering apparatus 10 will be described with reference to Figures 1 to 4. The soldering apparatus 10 is equipped with a heating head 11 for heating the workpiece 1 and a cooling head 31 for cooling the workpiece 1, both above the workpiece. The heating head 11 and the cooling head 31 have suction tubes (not shown) for sucking the workpiece. A heating block 60 for heating the collector 5 and a cooling block 70 for cooling the collector 5 are provided below the workpiece.

[0017] In this embodiment, the configuration on the head side and the configuration on the block side are combined to achieve high speed and high cycle performance in heating and cooling the workpiece.

[0018] Regarding the configuration above the workpiece 1, the heating head 11 is controlled in vertical and horizontal position by the driving force of a servo motor SM2, which corresponds to the first driving unit, via a link mechanism 40 including an arm 41, a first rod 42, etc., and via a movable device consisting of a heating-side first loader (not shown) and a heating-side second loader perpendicular to it. The heating-side first loader and the heating-side second loader correspond to the first driving unit described in the claims.

[0019] The heating head, cooling head, and device for sucking and adsorbing the workpiece in this embodiment have the same configuration as the heating head, cooling head, and device for sucking and adsorbing the workpiece of the soldering device described in Patent Publication No. 2022-040015.

[0020] The heating head 11 has suction tubes 25, 27 as first suction means capable of suctioning and releasing the workpiece 1 by air pressure, a ceramic heater as a heating device for heating the heating head 11, a sheathed thermocouple 21 as a head temperature sensor for adjusting the temperature of the heating head, and a contact thermocouple 13 as a contact temperature sensor that comes into contact with the workpiece 1 to adjust the temperature.

[0021] When the suction tubes 25, 27 are turned off and the workpiece 1 is not being held, the heating head 11 can be preheated by turning on the ceramic heater. Furthermore, when the workpiece 1 is held by turning on the suction tubes 25, 27, the sheathed thermocouple 21 is turned off, the contact thermocouple 13 is turned on, and the contact thermocouple 13 is brought into contact with the workpiece 1, thereby enabling highly accurate temperature control of the workpiece 1.

[0022] The cooling head 31 is controlled in position vertically and horizontally by the driving force of a servo motor SM1, which corresponds to a drive device, via a link mechanism including arms 94, 95, etc., and via a movable device consisting of, for example, a cooling-side first loader (not shown) and a cooling-side second loader perpendicular to it.

[0023] The cooling head 31 has a cooling device consisting of suction pipes 35, 36 as second suction means that can suction and release the workpiece 1 using air pressure, and a cooling water pipe (not shown). The cooling head 31 uses a movable device consisting of a cooling-side first loader and a cooling-side second loader to perform suction and release operations for lifting the workpiece 1 using the suction pipes 35, 36 of the workpiece 1, independently of the similar operations of the heating head 11.

[0024] Furthermore, the cooling head 31 is designed so that it is not affected by heat separated from the heating head 11 when cooling the workpiece 1, and is not affected by the ceramic heater or sheathed thermocouple. The cooling head 31 cools and cools the workpiece 1 independently of the operation of the heating head 11, which heats and increases the temperature of the workpiece 1. This allows for a short switching speed (fastest temperature increase / decrease) from workpiece heating to workpiece cooling. It has good thermal efficiency when raising and lowering the temperature of the workpiece 1.

[0025] Below the workpiece 1, the soldering device of this embodiment basically includes a heating block 60 that heats the collector 5 and a cooling block 70 that cools the collector 5. The cooling block 70 has a fixed level L that can support the lower surface of the collector 5 shown in Fig. 1(A). In contrast, the heating block 60 can reciprocate up and down relative to the cooling block 70 by a third drive unit 88 that corresponds to the servo motor SM3.

[0026] The heating block 60 is controlled in position in the vertical direction by a third driving unit 88 .

[0027] The heating block 60 has a suction tube 65 as a fourth suction means capable of suctioning and releasing the collector 5 by air pressure, a ceramic heater (not shown) as a heating device for heating the heating block 60, a sheath-type thermocouple (not shown) as a head temperature sensor for adjusting the temperature of the heating block 60, and a contact thermocouple as a contact-type temperature sensor that comes into contact with the collector 5 to adjust the temperature.

[0028] When the adsorption tube 65 is turned off and the heating block 60 is not holding the collector 5, the ceramic heater can be turned on to preheat the heating block 60. When the adsorption tube 65 is turned on and the collector 5 is held, the sheathed thermocouple is turned off and the contact thermocouple is turned on, and the contact thermocouple is brought into contact with the collector 5, thereby enabling highly accurate temperature control of the collector 5.

[0029] The cooling block 70 has a fixed position level L.

[0030] The cooling block 70 has a cooling device (not shown) consisting of a cooling water pipe and an adsorption pipe 75 as a third suction means capable of adsorbing and releasing the collector 5 by air pressure. The cooling block 70 performs the adsorption and release operations of the collector 5 by the adsorption pipe 75 independently from the similar operations of the heating block 60.

[0031] The cooling block 70 also has a heating / cooling device capable of raising and lowering the temperature, which corresponds to the fifth temperature sensor. The heating / cooling device is made up of a cartridge heater (cooling-side heating mechanism) and a sheath-type thermocouple (cooling-side block temperature control sensor).

[0032] The cooling block 70 and the cooling of the collector 5 are structured so as not to be affected by heat separated from the heating block 60, and are not affected by the ceramic heater and sheathed thermocouple. The cooling block 70 cools and cools the collector 5 independently of the operation of the heating block 60, which heats and raises the temperature of the collector 5. This allows for a short switching speed from collector heating to collector cooling (fastest temperature rise and fall). The thermal efficiency is good when raising and lowering the temperature of the collector 5.

[0033] The cooling block 70 or the heating block 60 can support the collector 5. The structure on the block side below the workpiece has separate heating and cooling functions.

[0034] 2, this embodiment includes a control device (PLC) 100 that controls the positions of the heating head 11, the cooling head 31, and the heating block 60. The control device 100 outputs instructions to servo motors SM1, SM2, and SM3, and the position (operation amount) of each arm is determined by driving each servo motor.

[0035] This embodiment includes a link mechanism 40 that compensates for the thermal expansion difference of the arms of the heating head 11 and corresponds to the thermal compression structure shown in FIGS.

[0036] As shown in FIGS. 3 and 4, the driving force of the driving unit 28 moves the heating head 11 up and down (raise and lower) via a link mechanism 40. In this configuration, the link mechanism 40 has a correction mechanism portion 44 shown in FIG. The correction mechanism 44 has a slider 47 corresponding to a movable part that is movable up and down while being guided by a rail 46 of an arm 41 corresponding to a fixed part. The slider 47 is fixed to the heating head 11 that is movable relative to the rail 46. One end of a connecting part 43 is rotatably supported on the upper end of a first rod 42 fixed to the heating head 11, and a second rod 45 is rotatably supported on the other end of the connecting part 43. The lower end of the second rod 45 is fixed to the arm 41.

[0037] The first rod 42 is made of a material with a relatively small expansion coefficient, such as Super Invar (thermal expansion coefficient 0.24 (×10 -6 / °C), and the second rod 45 is made of a material with a relatively large expansion coefficient, such as aluminum (coefficient of thermal expansion 27.3 (×10 -6 / ℃). For example, if the length of the first rod 42 and the second rod 45 is 20 mm, and the temperature difference between the temperature of the heating head 11 before and after heating is 80°C, the thermal expansion difference will be 0.043 mm. This thermal expansion difference is absorbed in a direction that cancels out (absorption direction) the expansion in the thermal expansion direction of the lower end of the heating head 11. This allows the thermal expansion of the entire arm to approach zero.

[0038] The control device 100 issues command values ​​of normal control amounts to the arms of the heating head 11, the cooling head 31, and the heating block 60. The arms equipped with servo motors for the up-down mechanism have their vertical heights controlled.

[0039] 2, this embodiment includes a PCL (control device) that acquires temperature information of each arm of the heating head 11, cooling head 31, and heating block 60 that adsorb the workpiece 1, and issues instructions to the heating head, cooling head, and heating block based on the temperature information of each arm, and drive units 28, 29, and 88 that consist of servo motors SM1, SM2, and SM3 that control the up and down positions of each arm 41 and first rod 42. The amount of thermal expansion of the tip of the first rod 42 is calculated from the temperature of the thermocouple that corresponds to the temperature sensor, and this is input into a control correction amount to be instructed and controlled.

[0040] The PLC acquires the temperature of the thermocouples on each arm of the heating head, cooling head, and heating block, and calculates the thermal expansion of the tip of each arm. The correction amount is acquired in advance from the temperature and thermal expansion during heating.

[0041] The PLC issues command values ​​that are the normal control amounts plus a thermal expansion correction amount to each arm of the heating head 11, the cooling head 31, and the heating block 60. Based on the command from the PLC, the arm equipped with a servo motor of the up / down mechanism controls the up / down height.

[0042] In this embodiment, the amount of thermal expansion of each arm is calculated and the vertical height of each arm is controlled to control the position, speed, and posture during soldering assembly, thereby improving the quality of soldering.

[0043] The arm supporting the heating head 11 is shown in FIGS. As shown in Figure 4, the soldering machine has a thermal compression structure in part of the arm that uses dissimilar metals with different amounts of thermal expansion. Because part of the arm is made of dissimilar metals with different amounts of thermal expansion, a rising motion is created due to the difference in thermal expansion, bringing the thermal expansion of the entire arm closer to zero. The amount of correction is set by the difference in thermal expansion.

[0044] The arm that supports the heating head 11 includes an arm 41 that corresponds to a fixed part, and a slider 47 that corresponds to a movable part that moves up and down in the axial direction.

[0045] (Table 1) JPEG0007803218000001.jpg41156

[0046] As shown in Table 1, the present invention uses dissimilar metals with different thermal expansion coefficients. The linear expansion coefficient of aluminum is 27.3(×10 -6 / ℃). The linear expansion coefficient of Super Invar is 0.24(×10 -6 / ℃). Super Invar is an alloy of iron, nickel, and cobalt, and is a metal material with an extremely small coefficient of thermal expansion at room temperature.

[0047] For example, by using dissimilar metals with different thermal expansion coefficients, such as aluminum and Super Invar, in the right places, it is possible to create a thermal expansion difference due to the difference in materials when a temperature difference occurs before and after heating.If the temperature difference before the equipment heats up (when the equipment starts operating) and after the heat rises up (when the temperature stabilizes after operation) is known, it is possible to cancel out the amount of thermal expansion by arbitrarily setting the length of the part made of different materials.

[0048] Next, the steps of the soldering operation from soldering preparation to soldering completion will be explained in order. <1st process>

[0049] As shown in Figure 5(A), an example of joining the workpiece 1 to the collector 5 side will be described. The semiconductor element 4 and spacer 3 are layered in this order on the top surface of the collector 5, and the workpiece 1 is soldered to the spacer 3. The workpiece 1 is carried into a soldering device 10. Below the workpiece 1, the workpiece 1 is transported above the solder 2 on the spacer 3 on the collector 5 side.

[0050] The soldering device 10 has a heating head 11 for heating the workpiece 1 and a cooling head 31 for cooling the workpiece 1 on the upper side of the workpiece, and a heating block 60 for heating the collector 5 and a cooling block 70 for cooling the collector 5 on the lower side of the workpiece.

[0051] The heating head 11 is located at a lower position than the cooling head 31. The collector 5, which serves as an object to be bonded, is placed on the heating block 60 below the heating head 11 and the cooling head 31. The collector 5 is sucked by the heating block 60 in the direction of arrow 90 using a suction tube 65. The heating block 60 is located at a higher position than the cooling block 70. <Second process>

[0052] The heating head 11 descends toward the workpiece 1 placed separately above the solder 2, and when it comes into contact with the workpiece 1 as shown in Figure 5(B), the suction tubes 25 and 27 are turned on, and the workpiece 1 is sucked in the direction of arrow 7 and adsorbed to the underside of the heating head 11. <3rd process>

[0053] Next, as shown in FIG. 5(C), with the heating head 11 holding the workpiece 1 by suction, the heating head 11 heats the workpiece 1 by heat conduction in the direction of arrow 8 and descends to melt the solder 2 and join the workpiece 1 by soldering. <4th process>

[0054] Next, as shown in FIG. 5(D), the heating block 60 is lowered, the upper surface of the cooling block 70 is brought into contact with the collector 5, and the suction tube 75 is turned on to suck air in the direction of arrow 89, thereby switching the collector 5 from suction by the heating block 60 to suction by the cooling block 70. <5th process>

[0055] Next, as shown in Figure 6(E), the cooling head 31 is lowered, and the underside of the cooling head 31 comes into contact with the workpiece 1, and the suction tubes 35, 36 are turned on to suck air in the direction of arrow 9, switching the workpiece 1 to simultaneous suction by the heating head 11 and the cooling head 31. The cooling block 70 supports the collector 5 and sucks the collector 5 with a suction tube 75 . <6th process>

[0056] Next, as shown in Figure 6(F), heat is removed in the direction of arrow 39 to promote cooling and increase the solder joining speed. The suction tubes 25 and 27 of the heating head 11 are turned off, and the heating head 11 is lifted from the workpiece 1. This switches to suction by the cooling head 31, and at the same time the cooling water tube 32 of the cooling head 31 is turned on to promote cooling of the workpiece 1 and the solder 2 joined to it. <7th process>

[0057] When the soldering is completed, as shown in Figure 6(G), the suction tubes 35 and 36 of the cooling head 31 are turned off to stop suction of the workpiece 1, the cooling head 31 is moved away from the workpiece 1, and the operation of the device is stopped. This completes the soldering.

[0058] According to this embodiment, the heating head 11 and the cooling head 31 are driven by different driving devices, and the suction and heating operation of the workpiece 1 and the suction and cooling operation of the workpiece 1 are performed independently, so that the heating operation and the cooling operation can be switched quickly by controlling the switching operation. Therefore, the heating, soldering, and cooling of the workpiece 1 can be performed quickly and efficiently, the thermal efficiency can be improved, and the workpiece 1 and the spacer 3 as the object to be joined can be joined at high speed with the solder 2.

[0059] In the above-described embodiment, the suction tubes 35, 36 of the cooling head 31 are turned on before the suction tubes 25, 27 of the heating head 11 are switched from on to off, and the reception of the workpiece 1 is switched from the heating head 11 to the cooling head 31, thereby improving the accuracy of the soldering joint position of two workpieces 1 at the same time.

[0060] In this embodiment, the position of the workpiece 1 is determined by suction using the suction tubes 25 and 27 of the heating head 11, and then, while the workpiece is being continuously lifted, the suction tubes 35 and 36 of the cooling head 31 simultaneously suction the workpiece 1, thereby improving positional accuracy.

[0061] With the soldering device of this embodiment, heating and cooling are independent of each other, so there is little temperature change in the heating head 11 and the cooling head 31, resulting in good cycleability. Also, since the workpiece 1 is heated while its temperature is directly detected by the contact thermocouples 13 and 14, defects are unlikely to occur. Rapid cooling of the solder 2 has the effect of making it difficult for voids to occur and improving the solder quality.

[0062] Furthermore, the furnace-less structure contributes to space saving, energy saving and equipment cost reduction, and the soldering equipment can be made compact, which has the advantage of being easy to maintain.

[0063] (Comparative form) A comparative example will be described with reference to FIGS.

[0064] As shown in Figure 10, soldering is completed through the steps of heating, assembly, cooling and transferring the collector side, and cooling and transferring the emitter side. In the comparative example, excessive pressing of the emitter during assembly causes solder overflow. One of the causes of excessive pressing of the emitter is thermal expansion of the heating head.

[0065] Figure 9 shows the change in the amount of thermal expansion of the heating head arm over time. As the heater heats up and time passes, the amount of thermal expansion increases. After the heater is turned on, the temperature rise is complete 5 minutes later, and the thermal expansion is complete 100 minutes later. After the heater heats up, the amount of thermal expansion is 0.28, which is larger than the required product precision of 0.1, and this can fluctuate due to abnormality treatment, etc., raising concerns about solder overflow.

[0066] In contrast to this, according to the above embodiment, even when the pre-heating temperature of the heating head reaches the post-heating temperature, the temperature difference is absorbed by the thermal expansion caused by the correction mechanism 44 having the link mechanism described above, so that excess solder can be absorbed by the fillet and the thickness of the solder layer can be controlled, thereby reducing solder quality defects due to solder overflow, etc.

[0067] Second Embodiment A second embodiment of the present invention will be described with reference to FIGS. 1, 2, 3 and 7. FIG.

[0068] The second embodiment is similar to the first embodiment in the configurations shown in Figures 1, 2 and 3. The second embodiment has the configuration shown in Figure 7 instead of Figure 4 of the first embodiment.

[0069] The heating head 11, the cooling head 31, and the heating block 60 each include an arm. The configuration of portion IV shown in FIG. 3 appears in the configuration between arm 41 and first rod 42 shown in FIG. 7. The relatively movable configuration comprises guide rail 46, which corresponds to the fixed portion, and slider 47, which corresponds to the movable portion that can move relatively to guide rail 46. The thermal compression adjustment mechanism comprises link mechanism 54. Link mechanism 54 has link 55 rotatably supported by fulcrum 57 at the tip of third rod 91, which is fixed to arm 41. Link 55 has fulcrum 56 at a position a distance a in one direction from fulcrum 57, and has fulcrum 58 at a position b distance in the opposite direction from fulcrum 57. Fulcrum 58 is fixed to the tip of fourth rod 92, which is fixed to arm 41.

[0070] The thermal expansion coefficient of the material of the third rod 91 is greater than the thermal expansion coefficient of the material of the fourth rod 92. For example, the third rod 91 is made of aluminum, and the fourth rod 92 is made of Super Invar. The correction amount is set based on the difference in thermal expansion. This allows the use of two different metal materials and the principle of leverage to compensate for the thermal expansion of the arms before and after heating by increasing the thermal expansion in a direction that cancels out the thermal expansion, creating an upward movement of the heating head 11 due to the difference in thermal expansion, compressing the thermal expansion and bringing the thermal expansion of the entire arm close to 0. Therefore, excess solder during soldering can be appropriately absorbed by the fillet, and the solder thickness can be appropriately controlled.

[0071] As shown in FIG. 7, in the second embodiment, the arm is provided with a link mechanism 54. A correction amount is set for the thermal expansion difference in the absorption direction opposite to the thermal expansion direction. When the arm 41 thermally expands and descends, the link mechanism 54 performs an upward movement to reduce the difference in thermal expansion.

[0072] The arms of the heating head 11 are shown in FIGS. As shown in Figure 7, the soldering machine has a thermal compression structure in part of the arm that uses dissimilar metals with different amounts of thermal expansion. Because part of the arm is made of two different metals with different amounts of thermal expansion, when a temperature difference occurs between before and after heating in the link mechanism, a thermal expansion difference can be created due to the difference in materials.

[0073] The thermal compression adjustment mechanism of the heating head 11 includes a fixed part and a movable part that moves up and down in the axial direction. A metal with a large thermal expansion rate and a metal with a small thermal expansion rate are provided in the fixed portion of the arm 41 so as to extend upward in the axial direction, which is the absorption direction. The fixed portion and movable portion of the arm are connected by a connecting fixed portion and a connecting movable portion. The metal of the fixed portion of the arm is a dissimilar metal (second metal) with a larger thermal expansion rate than the metal of the movable portion (first metal) and a dissimilar metal (third metal) with a smaller thermal expansion rate than the metal of the movable portion. The metal of the remaining portion of the fixed portion is the same type of first metal as the metal of the movable portion. The movable portion of the arm expands downward in the axial direction, which is the thermal expansion direction, due to thermal expansion when the temperature rises, but the second and third metals of the fixed portion expand more upward in the axial direction due to thermal expansion.

[0074] The amount of lift of the movable part due to the amount of thermal expansion of the metal of the fixed part that expands upward in the axial direction is greater than the amount of thermal expansion of the metal of the movable part that expands downward in the axial direction, bringing the amount of thermal expansion of the entire arm close to zero.

[0075] According to this embodiment, if the temperature difference between before the equipment heats up (when the equipment starts operating) and after the temperature rises (when the equipment starts operating and the temperature stabilizes) is known, it is possible to cancel the amount of thermal expansion by arbitrarily setting the length of the part made of a different material.

[0076] Other basic configurations of the second embodiment are similar to those of the first embodiment.

[0077] (Third embodiment) A third embodiment of the present invention will be described with reference to FIG.

[0078] 8, the third embodiment of the present invention includes a PLC (control device 100) that acquires temperature information from each of the arms 41, 93, 94, and 95 that support the heating head 11, cooling head 31, and heating block 60 that adsorb the workpiece, and issues commands to the heating head 11, cooling head 31, and heating block 60 based on the temperature information from each of the arms 41, 93, 94, and 95, and drive units 28, 29, and 88 that are made up of servo motors SM1, SM2, and SM3 that control the up and down positions of each arm. The amount of thermal expansion at the tip of the arm is calculated from the temperatures of thermocouples 101, 102, 103, 104, 105, 106, 107, and 108, which correspond to temperature sensors, and this is input into a control correction amount that is then instructed and controlled.

[0079] The control device (PLC) 100 acquires the temperatures of thermocouples 101, 102, 103, 104, 105, 106, 107, and 108 of each arm of the heating head 11, cooling head 31, and heating block 60, and calculates the amount of thermal expansion of the tip of each arm 93, 94, and 95. The amount of correction is acquired in advance from the temperature and amount of thermal expansion during temperature rise.

[0080] The PLC issues commands equivalent to the normal control values ​​plus a thermal expansion correction amount to the arms 41, 93, 94, and 95 that support the heating head 11, cooling head 31, and heating block 60. In response to commands from the PLC, the arms equipped with servo motors for the up / down mechanisms control the vertical heights of the heating head 11, cooling head 31, and heating block 60.

[0081] In this embodiment, the amount of thermal expansion of each arm 41, 93, 94, and 95 is calculated and the vertical height of each arm 41, 93, 94, and 95 is controlled to control the position, speed, and posture during soldering assembly, thereby improving the quality of soldering.

[0082] Other basic configurations of the third embodiment are similar to those of the first embodiment. The temperature of each arm is detected by a thermocouple, and the position, speed, and posture of the heating head can be corrected and controlled according to the detected temperature. Therefore, controlling the thickness of the solder layer δ improves soldering quality. Position control also allows excess solder to be absorbed by the fillet, improving soldering quality.

[0083] As described above, the present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit and scope of the present invention. In the soldering device of the present invention, the adjustment mechanism may be configured so that the heating head is supported by a material with a different thermal expansion coefficient, and the adjustment mechanism is equipped with a link mechanism (40) that changes the positional displacement of the heating head as the temperature of the heating head increases. In the soldering device of the present invention, the link mechanism may be configured to include a fixed part (41, 46) provided on the first drive part side, a movable part (47) that supports the heating head and is movable relative to the fixed part in the direction of gravity and the direction against gravity, and a correction mechanism part (44) that uses dissimilar metals with different amounts of thermal expansion between the fixed part and the movable part to bring the positional displacement of the heating head closer to zero.

[0084] In the soldering apparatus of the present invention, the correction mechanism may be configured to include a link mechanism (54) having a thermal compression mechanism that uses the principle of leverage. The soldering device of the present invention may be configured to include a slider (47) that allows relative movement between the fixed part and the movable part.

[0085] The soldering device of the present invention may be configured to include temperature sensors (101, 102, 103, 108) that detect the temperature of the arms (93, 94, 95) that affect the amount of displacement caused by thermal expansion of the heating head, and a control device (100) that sends a control signal to the first drive unit or the second drive unit to correct the thermal expansion corresponding to the temperature detected by the temperature sensor. [Explanation of symbols]

[0086] 1: Emitter (work), 2: solder, 5: Collector (object to be bonded), 10: Soldering equipment, 11: Heating head, 25, 27: Adsorption tube (first suction means), 28: Heating side first loader (first drive unit), 29: Heating side second loader (first drive unit), 31: Cooling head, 35, 36: Adsorption tube (second suction means), 60: Heating block, 65: Adsorption tube (fourth suction means), 70: Cooling block, 75: Adsorption tube (third suction means), 88: Third drive unit.

Claims

1. A soldering device that applies solder (2) to the top surface of an object to be joined (3), and then lowers a workpiece (1) from above the solder to join the workpiece to the object to be joined via the solder, a first suction means (25, 27) for sucking the upper surface of the workpiece with air to lift the workpiece; a heating head (11) having the first suction means and a temperature sensor capable of adjusting the temperature of the workpiece, and capable of moving up and down until it contacts the upper surface of the workpiece; a first driving unit (28) that drives the heating head so that it can be raised and lowered; a second suction means (35, 36) operable independently of the first suction means and sucking the upper surface of the workpiece with air to lift the workpiece; a cooling head (31) having the second suction means and a cooling device capable of cooling the workpiece, operable independently of the heating head, and capable of moving up and down until it abuts on the upper surface of the workpiece; a second drive unit (29) that drives the cooling head so that it can be raised and lowered; a heater provided in the heating head and configured to heat the heating head; an adjustment mechanism (40) that creates an upward movement due to the thermal expansion difference of the heating head; a control device (100) that outputs command values ​​for controlling the positions of the heating head and the cooling head to the first drive unit and the second drive unit.

2. 2. The soldering apparatus according to claim 1, wherein the adjustment mechanism includes a link mechanism (40) for changing the positional displacement of the heating head in accordance with an increase in temperature of the heating head.

3. 3. The soldering device of claim 2, wherein the link mechanism comprises a fixed part (41, 46) provided on the first drive part side, a movable part (47) that supports the heating head and is movable relative to the fixed part in the direction of gravity and the direction against gravity, and a correction mechanism part (44) that uses dissimilar metals with different amounts of thermal expansion between the fixed part and the movable part to bring the positional displacement of the heating head closer to zero.

4. 4. The soldering apparatus according to claim 3, wherein the correction mechanism comprises a link mechanism having a thermal compression mechanism that uses the principle of leverage.

5. 4. The soldering apparatus of claim 3, further comprising a slider (47) for enabling relative movement between said fixed part and said movable part.

6. 2. The soldering apparatus according to claim 1, further comprising: a temperature sensor (101, 102, 103, 108) for detecting the temperature of the arm (93, 94, 95) which affects the amount of displacement of the thermal expansion of the heating head; and a control device (100) for sending a control signal to the first driving unit or the second driving unit to correct the thermal expansion corresponding to the temperature detected by the temperature sensor.

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