Automatic brazing device and automatic brazing method

Abstract

An automatic brazing device (100) comprises: a workpiece heating part that heats a brazing site of a workpiece W; a workpiece heating movement part that moves the workpiece heating part relative to the brazing site; a nozzle (40) through which a wire brazing material (1) is inserted, toward the brazing site; a nozzle heating part that heats the nozzle (40); a temperature sensor (41) that measures the temperature of the nozzle (40); a temperature evaluation part that evaluates, relative to a preset temperature, the measured temperature of the nozzle (40) which was measured by the temperature sensor (41); and a nozzle heating control part that controls the heating of the nozzle (40) on the basis of the result of the evaluation by the temperature evaluation part.

Description

[Technical field]

[0001] The present disclosure relates to an automated brazing apparatus and an automated brazing method. [Background technology]

[0002] Conventional automatic brazing apparatuses are described, for example, in Patent Document 1 and Patent Document 2. These automatic brazing apparatuses include a means for detecting the temperature of the members to be brazed, a means for heating the members to be brazed, a means for calculating the amount of heat based on the detected temperature, a means for setting the supply time of the brazing material, a means for controlling the heating means, and a means for supplying the brazing material and brazing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-98151 A [Patent Document 2] Patent No. 3117196 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional configuration, the brazing material is supplied at a low temperature. If the temperature is low, it is necessary to increase the temperature of the brazing material and wait for the supply after the brazing material nozzle approaches the workpiece W. This poses the problem of a long brazing time.

[0005] The present disclosure has been made in consideration of the above-mentioned circumstances, and has an object to provide an automatic brazing apparatus and an automatic brazing method that can preheat a brazing material and perform brazing in a short time. [Means for solving the problem]

[0006] In order to achieve the above-mentioned objective, the automatic brazing apparatus of the present disclosure comprises a work heating unit that heats the brazing point of the workpiece, a work heating movement unit that moves the work heating unit toward the brazing point, a nozzle through which a wire brazing material heading toward the brazing point is inserted, a nozzle heating unit that heats the nozzle, a temperature measurement unit that measures the temperature of the nozzle, a temperature determination unit that determines the measured temperature of the nozzle measured by the temperature measurement unit against a predetermined temperature, and a nozzle heating control unit that controls the heating of the nozzle based on the result determined by the temperature determination unit. Effect of the Invention

[0007] In the present disclosure, the nozzle heating section heats the nozzle, and the measured temperature of the nozzle measured by the temperature measuring section is judged against a preset temperature. Then, based on the judgment result, the operation of the nozzle heating moving section is controlled. Therefore, according to the present disclosure, the brazing material is preheated and brazing can be performed in a short time. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a front view of an automatic brazing device according to a first embodiment of the present disclosure. [Diagram 2] FIG. 1 is a block diagram of an automatic brazing device according to a first embodiment of the present disclosure. [Diagram 3] 1 is a flowchart showing a brazing process of an automatic brazing device according to a first embodiment of the present disclosure. [Figure 4] 1 is a flowchart showing a nozzle heating process of an automatic brazing device according to a first embodiment of the present disclosure. [Diagram 5] 1 is a flowchart showing a brazing material supply process of an automatic brazing device according to a first embodiment of the present disclosure. [Figure 6] FIG. 1 is a front view of a brazing material supply position of an automatic brazing device according to a first embodiment of the present disclosure; [Figure 7] FIG. 11 is a partially enlarged view showing a main part of an automatic brazing device according to a second embodiment of the present disclosure. [Figure 8] FIG. 1 is a block diagram of an automatic brazing device according to a second embodiment of the present disclosure. [Figure 9]11 is a flowchart showing a nozzle heating process according to a second embodiment of the present disclosure. [Figure 10] FIG. 11 is a front view of an automatic brazing device according to a third embodiment of the present disclosure. [Figure 11] Block diagram of an automatic brazing device according to a third embodiment of the present disclosure. [Figure 12] 13A, 13B, 13C, and 13D are explanatory diagrams showing a main part of an automatic brazing apparatus according to a third embodiment of the present disclosure, in which (a) is a state 1, (b) is a state 2, (c) is a state 3, and (d) is a state 4. [Figure 13] 10 is a flowchart showing a brazing process of an automatic brazing device according to a third embodiment of the present disclosure. [Figure 14] A flowchart showing a nozzle heating process of an automatic brazing device according to a third embodiment of the present disclosure. [Figure 15] 11 is a flowchart showing a brazing material supply process of an automatic brazing device according to a third embodiment of the present disclosure. [Figure 16] FIG. 13 is a partially enlarged view showing a main part of an automatic brazing device according to a fourth embodiment of the present disclosure. [Figure 17] FIG. 11 is a block diagram of an automatic brazing device according to a fourth embodiment of the present disclosure. [Figure 18] 11 is a flowchart showing a nozzle heating process according to a fourth embodiment of the present disclosure. [Figure 19] FIG. 13 is a partially enlarged view showing a main part of an automatic brazing device according to a fifth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, specific embodiments of the automatic brazing apparatus according to the present disclosure will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the following embodiments.

[0010] Embodiment 1 An automatic brazing apparatus and an automatic brazing method according to a first embodiment will be described with reference to FIGS.

[0011] The automatic brazing apparatus 100 includes a positioning mechanism 10, a nozzle heating mechanism 20, a brazing material supplying mechanism 30, a fixing jig 50, and a workpiece heating mechanism 70. The nozzle heating mechanism 20 heats a nozzle 40, which will be described later. The brazing material supplying mechanism 30 supplies brazing material to the nozzle 40. The workpiece heating mechanism 70 heats the workpiece W.

[0012] The positioning mechanism 10 includes an arm 11 with a plurality of joints. The position of the arm 11 can be freely changed by the movement of the joints. The arm 11 has a tip 11a at its tip that is rotatable around an axis.

[0013] The nozzle heating mechanism 20 includes a torch 28 and a torch cylinder 27. The torch 28 emits a flame 29 from one end thereof to heat the nozzle 40. The torch 28 is attached to the torch cylinder 27. The torch 28 is movable by a positioning mechanism 10. The fuel for the flame 29 is a combustible gas. The torch cylinder 27 supports the torch 28 and also moves the torch 28 back and forth to position it. The direction in which the flame 29 is emitted from the torch 28 is defined as the forward direction.

[0014] The workpiece heating mechanism 70 includes a torch 78 and a torch cylinder 77. The torch 78 emits a flame 79 from one end to heat the workpiece W, for example, to preheat the workpiece W. The torch 78 is attached to the torch cylinder 77. The torch 78 is movable by a positioning mechanism 10. The fuel for the flame 79 is the same flammable gas as the flame 29. The torch cylinder 77 supports the torch 78, as does the torch cylinder 27, and moves the torch 78 back and forth to position it. The direction in which the flame 79 is emitted from the torch 78 is defined as the forward direction.

[0015] The brazing material supplying mechanism 30 includes a pair of rollers 31. The brazing material supplying mechanism 30 holds the brazing wire material 1 supplied from the wound coil material 1a between the rollers 31. The brazing material supplying mechanism 30 feeds the brazing wire material 1 toward the nozzle 40 while holding the brazing wire material 1. The brazing material supplying mechanism 30 may further include a passage, a support, etc. for feeding the brazing wire material 1 to the nozzle 40 in any configuration.

[0016] The fixing jig 50 is attached to the tip 11a of the positioning mechanism 10. The nozzle 40 and the torch cylinder 27 are attached to the fixing jig 50. The nozzle 40 guides the brazing wire 1 by inserting it therethrough. The torch cylinder 27 moves the torch 28 forward and backward. Therefore, the nozzle 40, the torch cylinder 27, and the torch 28 attached to the torch cylinder 27 move together with the movement of the arm 11 and the tip 11a of the positioning mechanism 10.

[0017] The automatic brazing apparatus 100 also includes hoses 24a and 24b, flow rate control devices 21a and 21b, and a gas mixer 22. The hoses 24a and 24b supply gas to the nozzle heating mechanism 20 and the workpiece heating mechanism 70. The flow rate control devices 21a and 21b control the flow rates of gas in the hoses 24a and 24b. The gas mixer 22 is connected to the outlet sides of the hoses 24a and 24b. The hoses 24a and 24b are each connected to a supply source (not shown). A flammable gas flows in the hose 24a, and a combustion-supporting gas flows in the hose 24b. The flammable gas is, for example, city gas or propane gas, and the combustion-supporting gas is, for example, oxygen gas.

[0018] The flow rate control device 21a is provided in the middle of the hose 24a. The flow rate control device 21a controls the flow rate of the flammable gas. The flow rate control device 21b is provided in the middle of the hose 24b. The flow rate control device 21b controls the flow rate of the combustion supporting gas. The gas mixer 22 mixes the flammable gas and the combustion supporting gas supplied from the hoses 24a and 24b to produce a mixed gas.

[0019] The automatic brazing apparatus 100 further includes a branch pipe 23 and hoses 25a, 25b, and 25c. The branch pipe 23 and the hoses 25a, 25b, and 25c supply gas separately to the nozzle heating mechanism 20 and the workpiece heating mechanism 70. One end of the hose 25c is connected to the outlet side of the gas mixer 22. The branch pipe 23 is connected to the other end of the hose 25c. The outlet side of the branch pipe 23 branches into two. One end of the hose 25a and one end of the hose 25b are connected to the outlet side of the branch pipe 23. The other end of the hose 25a is connected to the torch 28. The other end of the hose 25b is connected to the torch 78.

[0020] The mixed gas is discharged from the gas mixer 22. The mixed gas passes through the hose 25c and the branch pipe 23, and then is divided into hoses 25a and 25b and flows. The hose 25a is connected to the torch 28. The hose 25b is connected to the torch 78. That is, the mixed gas of the combustible gas and the combustion supporting gas from the same supply source is branched and supplied to the torch 28 for heating the nozzle 40 and the torch 78 for heating the workpiece W.

[0021] Also, the flow rates of the mixed gas flowing to torch 28 and torch 78 may be controlled separately without using branch pipe 23. In this case, two each of gas mixer 22, flow rate control devices 21a, 21b, and hoses 24a, 24b, and 25c are prepared. Then, hose 25a connected to torch 28 and hose 25b connected to torch 78 are connected independently. With the configuration of this embodiment, flow rate control becomes easy, and position adjustment of torch cylinder 27, which will be described later, becomes easy.

[0022] The automatic brazing apparatus 100 further includes a nozzle 40, a temperature sensor 41, and a temperature recorder .

[0023] The nozzle 40 is a member for sending the brazing wire 1 to the vicinity of the workpiece W. The tip of the nozzle 40 is provided with a hole that is slightly larger than the diameter of the brazing wire 1. The brazing wire 1 is sent toward the workpiece W through this hole.

[0024] The temperature sensor 41 is attached to the nozzle 40. Any type of temperature sensor 41 may be used. The temperature sensor 41 is connected to a temperature recorder 42. The temperature recorder 42 successively records the temperature of the nozzle 40 measured by the temperature sensor 41. The temperature sensor 41 is indicated by a dotted line in the drawing. Alternatively, the temperature sensor 41 may be located outside the nozzle 40 or may pass through the inside of the nozzle 40.

[0025] When the torch 28 and the nozzle 40 approach each other, the temperature of the nozzle 40 increases. When the torch 28 and the nozzle 40 move away from each other, the temperature of the nozzle 40 decreases. In FIG. 1, when the torch cylinder 27 advances, the nozzle 40 is positioned at a position where the temperature of the nozzle 40 increases due to the flame 29 of the torch 28. When the torch cylinder 27 retreats, the nozzle 40 is positioned at a position where the temperature of the nozzle 40 decreases. The stroke and cylinder installation positions of the torch cylinder 27 and the workpiece heating mechanism 70 are determined according to the brazing conditions, such as the type of gas in the nozzle heating mechanism 20, the brazing time, and the flow rate.

[0026] The brazing wire material 1 used for brazing includes copper phosphorus brazing, aluminum brazing, etc. The upper and lower limit temperatures of the nozzle 40 vary depending on the brazing wire material 1 used. In the present embodiment, the brazing wire material 1 is a copper phosphorus brazing (BCuP-2) wire material.

[0027] FIG. 2 is a block diagram showing the functions of the automatic brazing apparatus 100 according to the first embodiment.

[0028] The automatic brazing apparatus 100 includes a control unit 101. The control unit 101 includes a CPU (Central Processing Unit), a RAM (Random-Access Memory), etc., and controls the operation of each of the above-mentioned units. In addition to those described above, the apparatus may include input means such as a keyboard and a mouse, and display means such as a display, in any configuration.

[0029] The control unit 101 includes a temperature determination unit 110 , a torch cylinder control unit 120 , a brazing material supply mechanism control unit 130 , a positioning mechanism control unit 140 , a flow control device control unit 150 , a heating mechanism control unit 160 , and a storage device 170 .

[0030] The temperature determination unit 110 determines whether or not the measured temperature of the torch 28 reaches, for example, a reference value.

[0031] The torch cylinder control unit 120 controls the torch cylinder 27 in accordance with the determination by the temperature determination unit 110 .

[0032] The brazing material supply mechanism control unit 130 controls whether or not the brazing material supply mechanism 30 supplies the wire brazing material 1 and the supply speed.

[0033] The positioning mechanism control unit 140 controls the position of the nozzle 40 according to each brazing process.

[0034] The flow rate control device control section 150 controls the operation of the flow rate control devices 21a and 21b to adjust the flow rates of the flammable gas and the combustion supporting gas.

[0035] The heating mechanism control unit 160 controls the operation of the workpiece heating mechanism 70 in accordance with the brazing process.

[0036] The storage device 170 includes, for example, a hard disk, a memory, etc. The upper and lower limit temperature settings of the nozzle 40 are stored in the storage device 170. In addition, the storage device 170 stores various parameters related to brazing for the nozzle heating mechanism 20, the brazing material supply mechanism 30, the positioning mechanism 10, and the flow rate control devices 21a and 21b as a brazing program.

[0037] The control unit 101 executes a temperature determination step of determining the measured temperature of the nozzle 40 against a preset temperature. The control unit 101 also executes a nozzle heating control step of controlling the heating of the nozzle 40 based on the result determined in the temperature determination step. The control unit 101 also executes a nozzle heating movement control step of controlling the operation of the nozzle heating movement unit based on the result determined in the temperature determination step. The nozzle heating movement control step includes a first movement control step for heating the workpiece W and a second movement control step for heating the nozzle 40.

[0038] The automatic brazing according to the first embodiment will be described with reference to the flow charts of Figs. 3 to 5. In the first embodiment, the workpiece W is set in advance. In the automatic brazing apparatus 100, settings related to heating the workpiece W, settings related to heating the nozzle 40, and settings related to supply of the brazing wire material 1 are stored in a sequencer, PC, etc. The settings related to heating the workpiece W are, for example, a flow rate and a heating time. The settings related to heating the nozzle 40 are, for example, an upper limit temperature and a lower limit temperature. The settings related to supply of the brazing wire material 1 are, for example, teaching of the brazing point, the supply amount of the brazing wire material 1, and the drive speed of the brazing wire supply mechanism 30.

[0039] The brazing process of the automatic brazing apparatus 100 will be described below with reference to Fig. 3. In the brazing process described below, each part of the automatic brazing apparatus 100 operates based on the control of the control unit 101.

[0040] In the brazing process, the automatic brazing apparatus 100 first performs a heating process on the nozzle 40 (step S1). In step S1, the control unit 101 controls the temperature of the nozzle 40 to be within a range between an upper limit temperature and a lower limit temperature. Next, the control unit 101 moves the work heating mechanism 70 to a position close to the work W (step S2). Next, the automatic brazing apparatus 100 heats the work W and waits in a heated state for a set time until the work W reaches a temperature suitable for brazing (step S3). To heat the work W, the work heating mechanism 70 may perform a reciprocating operation to stabilize the temperature rise of the work W. Next, the automatic brazing apparatus 100 performs a supply process of the wire brazing material 1 (step S4).

[0041] When step S4 is completed, the supply of the brazing wire material 1 is completed. After the brazing is completed, the automatic brazing apparatus 100 retracts the workpiece heating mechanism 70 and the positioning mechanism 10 (step S5). The retracted positions are a position where the workpiece heating mechanism 70 does not heat the workpiece W, or a position where the nozzle 40 is sufficiently far away from the torch 78 of the workpiece heating mechanism 70 so as not to be affected by the flame 79.

[0042] Next, the control unit 101 checks whether there is a next brazing operation (step S6). If there is a next brazing operation (step S6; Yes), the process returns to step S1. If there is no next brazing operation (step S6; No), the process ends. When the next brazing operation is performed, the workpiece W may be placed by automatic transport or may be placed by a worker.

[0043] Next, the heat treatment of the nozzle 40 of the automatic brazing apparatus 100 will be described with reference to FIG.

[0044] First, the control unit 101 acquires the temperature from the temperature sensor 41 that measures the temperature of the nozzle 40 (step S11).

[0045] Next, the control unit 101 performs a temperature determination step to determine whether the acquired temperature is equal to or higher than a lower limit temperature (step S12). An upper limit temperature and a lower limit temperature are set for the temperature of the nozzle 40. The upper limit temperature is set to a temperature equal to or lower than the melting temperature of the brazing wire material 1. The lower limit temperature is set to a temperature at which the brazing wire material 1 is preheated and melts quickly when the brazing wire material 1 comes into contact with the workpiece W, based on the brazing conditions. In the case of phosphorus copper brazing (BCuP-2), the temperature at which melting begins is approximately 710°C, so for example, the upper limit temperature is set to 650°C and the lower limit temperature is set to 550°C.

[0046] In step S12, if the temperature of the nozzle 40 is below the lower limit (step S12; No), the automatic brazing apparatus 100 performs a movement control step process to advance the torch cylinder 27 and heat it until the temperature reaches or exceeds the lower limit temperature (step S13). After step S13, the process returns to step S11. If the temperature of the nozzle 40 is above the lower limit (step S12; Yes), the control unit 101 determines whether the temperature of the nozzle 40 is below the upper limit temperature (step S14).

[0047] If the temperature of the nozzle 40 is higher than the upper limit (step S14; No), the automatic brazing apparatus 100 performs a movement control step of moving the torch cylinder 27 backward to lower the temperature of the nozzle 40 (step S15). After step S15, the process returns to step S11.

[0048] If the temperature of the nozzle 40 is equal to or lower than the upper limit (Step S14; Yes), the automatic brazing apparatus 100 moves the torch cylinder 27 to the origin (Step S16). In Step S16, the automatic brazing apparatus 100 retracts the torch cylinder 27. The first reason for retracting the torch cylinder 27 is to reduce the effect of heating the workpiece W. The second reason is to prevent the temperature of the nozzle 40 from rising too high, causing the wire brazing material 1 to melt inside the nozzle 40.

[0049] By performing steps S11 to S16, the nozzle 40 can perform brazing at a temperature close to the range between the upper limit temperature and the lower limit temperature.

[0050] Next, the supplying process of the brazing wire material 1 by the automatic brazing apparatus 100 will be described with reference to FIG.

[0051] First, the automatic brazing apparatus 100 uses the positioning mechanism 10 to move the nozzle 40 to a supply position for the brazing wire material 1 (step S21). Fig. 6 shows an enlarged view of the supply position for the brazing wire material 1. In Fig. 6, the supply position for the brazing wire material 1 will be described assuming that the workpieces W are pipes brazed together. One end of the pipe is expanded, and the other straight pipe is inserted into the expanded pipe section. To supply the brazing wire material to the expanded pipe section, the positioning mechanism 10 is moved to a position where the brazing wire material 1 is located above the boundary between the expanded pipe section and the straight pipe section.

[0052] Next, the automatic brazing apparatus 100 waits for the brazing wire 1 for a set time (step S22). The purpose of waiting is to heat the brazing wire 1 to near its melting temperature by the flame 79 for heating the workpiece W, or by heat transfer from the workpiece W, or by both. After that, the automatic brazing apparatus 100 drives the brazing wire supply mechanism 30 to feed a specified amount of the brazing wire 1 and supply it to the workpiece W (step S23). With the above process, the brazing wire supply process is completed.

[0053] According to the configuration of this embodiment, the nozzle 40 is heated to a set temperature range, and the brazing wire material 1 is heated. By heating the brazing wire material 1, the set time for heating to the vicinity of the melting temperature shown in step S22 of Fig. 5 can be shortened. Therefore, according to this embodiment, the cost and time required for the brazing process can be reduced, and the productivity can be improved.

[0054] When brazing processes are performed successively, after the brazing wire material 1 is supplied, the brazing wire material 1 is warmed by the flame 79 for heating the workpiece W and heat transfer from the workpiece W. Even in this case, the nozzle 40 is kept within the set temperature range by the heating process of the nozzle 40 shown in step S1 of Fig. 3 and Fig. 4. This makes it possible to reduce the temperature change of the brazing wire material 1 for each brazing process, thereby enabling stable brazing, and as a result, improving the quality of the brazing.

[0055] Furthermore, in this embodiment, the gas supply for the torch 78 for heating the workpiece W and the torch 28 for heating the nozzle 40 is the same supply source. This makes it possible to configure the device at low cost.

[0056] Embodiment 2 In the first embodiment, the torch cylinder 27 is used to heat the nozzle 40. However, as shown in Fig. 7, an electric cylinder 80 may be used instead of the torch cylinder 27. The torch cylinder 27 is controlled at two positions, the forward position and the backward position of the air cylinder. In contrast, the electric cylinder 80 can perform position control at multiple points.

[0057] 8 is a block diagram of an automatic brazing apparatus 100 according to the second embodiment. The control unit 101 includes a temperature determination unit 101 and an electric cylinder control unit 120a. The temperature determination unit 101 calculates the temperature difference between the measured temperature of the nozzle 40 and a reference temperature. The electric cylinder control unit 120a determines the position of the electric cylinder based on the temperature difference.

[0058] 9 shows a flow chart of the heating process of the nozzle 40 according to the embodiment 2. Note that the brazing process and the supply process of the brazing wire material 1 are the same as those in the embodiment 1.

[0059] Steps S31, S32, and S35 are the same as steps S11, S12, and S14, respectively, in embodiment 1. After acquiring the temperature of the nozzle 40 (step S31), the control unit 101 determines whether the acquired temperature is equal to or higher than a lower limit temperature (step S32).

[0060] In step S32, if the temperature of the nozzle 40 is less than the lower limit (step S32; No), the control unit 101 calculates the temperature difference between the nozzle temperature and the lower limit temperature (step S33). After that, the control unit 101 advances the electric cylinder 80 according to the temperature difference (step S34). After step S34, the process returns to step S31.

[0061] In step S32, if the temperature of the nozzle 40 is equal to or higher than the lower limit (step S32; Yes), the control unit 101 determines whether the temperature of the nozzle 40 is equal to or lower than the upper limit temperature (step S35).

[0062] In step S35, if the temperature of the nozzle 40 is higher than the upper limit (step S35; No), the control unit 101 calculates the temperature difference between the nozzle temperature and the lower limit temperature (step S36). After that, the automatic brazing apparatus 100 moves the electric cylinder 80 backward in accordance with the temperature difference (step S37). The backward movement is the opposite operation to the forward movement in step S34. After step S37, the process returns to step S31.

[0063] If the temperature of the nozzle 40 is equal to or lower than the upper limit (Step S35; Yes), the automatic brazing apparatus 100 moves the electric cylinder 80 to the origin (Step S38). In Step S38, the control unit 101 sets the origin to a position where the torch 28 operating together with the electric cylinder 80 has minimal effect on heating the workpiece W. Then, the automatic brazing apparatus 100 moves the torch 28 to the origin.

[0064] By performing steps S31 to S38, the nozzle 40 can perform brazing at a temperature close to the range between the upper limit temperature and the lower limit temperature.

[0065] According to the configuration of the second embodiment, in addition to the effects of the first embodiment, it is possible to accurately control the nozzle 40 within a set temperature range, which further improves the quality of the brazing.

[0066] Embodiment 3 In the first embodiment, there are separate torches 28 for heating nozzle 40 and 78 for heating workpiece W. However, one torch may be used to heat both nozzle 40 and workpiece W.

[0067] 10 shows a front view of an automatic brazing apparatus 100 according to the third embodiment. A torch cylinder 27 and a nozzle cylinder 90 are provided on a fixture 50. The torch cylinder 27 operates a torch 28. The nozzle cylinder 90 operates a nozzle 40. The third embodiment does not have the work heating mechanism 70 of the first embodiment. Therefore, a hose 25 is connected alone from the outlet of the gas mixer 22 to the torch 28.

[0068] 11 is a block diagram of an automatic brazing apparatus 100 according to embodiment 3. The control unit 101 includes a temperature determination unit 110, a torch cylinder control unit 120, and a nozzle cylinder control unit 120b. The temperature determination unit 110, the torch cylinder control unit 120, and the nozzle cylinder control unit 120b determine the operations of the torch cylinder 27 and the nozzle cylinder 90 according to the temperature.

[0069] According to the configuration of this embodiment, in addition to the effects of the first and second embodiments, the torch 28 that heats the nozzle 40 also functions as a heating mechanism that heats the workpiece W. Therefore, the automatic brazing device can be made smaller and less expensive.

[0070] 12(a) to (d) are diagrams illustrating the states of the main parts of the automatic brazing apparatus 100 according to the third embodiment. States 1 to 4 show the torch cylinder 27 and the nozzle cylinder 90 in the forward and backward positions, respectively. State 1 in FIG. 12(a) is the original position. State 1 is a state in which the workpiece W is heated and the nozzle 40 is radiated heat to reduce the temperature. State 2 in FIG. 12(b) is a state in which the workpiece W is heated more gently than in state 1 and the nozzle 40 is radiated heat to reduce the temperature. State 3 in FIG. 12(c) and state 4 in FIG. 12(d) are states in which the workpiece W is heated while the brazing wire 1 is being supplied and the nozzle 40 is heated to increase the temperature.

[0071] The automatic brazing according to the third embodiment will be described with reference to the flow charts of FIGS.

[0072] The brazing process of the automatic brazing apparatus 100 will be described below with reference to Fig. 13. First, the automatic brazing apparatus 100 performs a heat treatment of the nozzle 40 (step S41). In step S41, the control unit 101 controls the temperature of the nozzle 40 to be within a range between an upper limit temperature and a lower limit temperature.

[0073] Next, the automatic brazing apparatus 100 causes the positioning mechanism 10 to move the nozzle 40 to a position close to the workpiece W (step S42).

[0074] Next, the automatic brazing apparatus 100 heats the workpiece W and waits in the heated state for a set time until the workpiece W reaches a temperature suitable for brazing (step S43). To heat the workpiece W, the torch cylinder 27 may perform a reciprocating motion to stabilize the temperature rise of the workpiece W. Thereafter, the automatic brazing apparatus 100 performs a supply process of the brazing wire material 1 (step S44).

[0075] When step S44 is completed, the supply of the brazing wire material 1 is completed. After the brazing is completed, the automatic brazing apparatus 100 causes the positioning mechanism 10 to retract the nozzle 40 (step S45). The retracted position is a position where the workpiece W is not heated, that is, a position where the workpiece W is not affected by the flame 29.

[0076] Next, the control unit 101 checks whether there is a next brazing operation (step S46). If there is a next brazing operation (step S46; Yes), the process returns to step S41, and if there is no next brazing operation (step S46; No), the process ends. When the next brazing operation is performed, the workpiece W may be placed by automatic transport or may be placed by an operator. Alternatively, the nozzle 40 may be moved to the position of another workpiece W by the positioning mechanism 10.

[0077] Next, the heat treatment of the nozzle 40 of the automatic brazing apparatus 100 will be described with reference to FIG.

[0078] First, the control unit 101 acquires the temperature from the temperature sensor 41 that measures the temperature of the nozzle 40 (step S51).

[0079] Next, the control unit 101 judges whether the acquired temperature is equal to or higher than the lower limit temperature (step S52). In step S52, if the temperature of the nozzle 40 is lower than the lower limit (step S52; No), the automatic brazing apparatus 100 heats the nozzle 40 until the temperature becomes equal to or higher than the lower limit temperature (step S53).

[0080] The nozzle 40 is heated by setting the nozzle 40 to state 3 in Fig. 12(c) or state 4 in Fig. 12(d). At this time, care must be taken not to melt the brazing wire 1 protruding from the nozzle 40. If the brazing wire 1 melts when set to state 3 or state 4, the brazing wire supply mechanism 30 is operated in the reverse direction from the supply direction to return the brazing wire 1 to the inside of the nozzle 40. After step S53, the process returns to step S51.

[0081] If the temperature of the nozzle 40 is equal to or higher than the lower limit (Step S52; Yes), the control unit 101 judges whether the temperature of the nozzle 40 is equal to or lower than the upper limit temperature (Step S54). If the temperature of the nozzle 40 is higher than the upper limit (Step S54; No), the control unit 101 causes the nozzle 40 to dissipate heat until the temperature becomes equal to or lower than the upper limit temperature (Step S55). The nozzle heat dissipation process is performed when the nozzle 40 is in State 1 of FIG. 12(a) or State 2 of FIG. 12(b). After Step S55, the process returns to Step S51.

[0082] If the temperature of the nozzle 40 is equal to or lower than the upper limit (Step S54; Yes), the control unit 101 moves the torch cylinder 27 and the nozzle cylinder 90 to the origin (Step S56). In Step S56, the control unit 101 moves the torch cylinder 27 and the nozzle cylinder 90 to the position of State 1 in FIG. 12(a). State 1 is a position where the nozzle 40 is least affected by heating.

[0083] By performing steps S51 to S56, the nozzle 40 can perform brazing at a temperature close to the range between the upper limit temperature and the lower limit temperature.

[0084] Next, the supplying process of the brazing wire material 1 by the automatic brazing apparatus 100 will be described with reference to FIG.

[0085] First, the automatic brazing apparatus 100 advances the nozzle cylinder 90 (step S61). At this time, the nozzle 40 is in a position of State 3 in Fig. 12(c) or State 4 in Fig. 12(d). Also, referring to Fig. 6, the wire brazing material 1 is positioned above the boundary between the expanded pipe portion and the straight pipe portion of the workpiece W.

[0086] Next, the automatic brazing apparatus 100 waits for a set time (step S62). The waiting is for the purpose of heating the brazing wire 1 to near its melting temperature by the flame 29 for heating the workpiece W, or by heat transfer from the workpiece W, or by both.

[0087] Next, the automatic brazing apparatus 100 drives the brazing material supply mechanism 30 to feed a specified amount of the brazing wire material 1 and supply it to the workpiece W (step S63). With the above processing, the brazing material supply processing is completed.

[0088] In this embodiment, similarly to the first embodiment, the nozzle 40 is heated to a set temperature range to warm the brazing wire material 1. Furthermore, according to this embodiment, the number of torches in the heating mechanism can be reduced.

[0089] Embodiment 4 In the first to third embodiments, the flame 29 from the torch 28 is used to heat the nozzle 40. Alternatively, as shown in FIG. 16, an electric heater 60 may be used to heat the nozzle 40. The electric heater 60 generates heat by resistance heating, and is connected to a regulator (not shown). The electric heater 60 is in contact with the nozzle 40. In the fourth embodiment, the amount of heat generated is controlled by adjusting the current flowing through the electric heater 60.

[0090] The electric heater 60 needs to be installed at a position away from A in Fig. 16. If a flame is used in the workpiece heating mechanism 70, and A is the range of influence of the flame, there is a possibility that the electric heater 60 will break down if it is affected by the flame. Also, it is preferable for the temperature sensor 41 to acquire the nozzle tip temperature, that is, the temperature at a position close to the tip of the wire brazing material 1. For that reason, it is better to install the temperature sensor 41 closer to the nozzle tip than the electric heater 60.

[0091] 17 is a block diagram of an automatic brazing apparatus 100 according to embodiment 4. The control unit 101 includes an electric heater control unit 61 that controls the amount of heat generated by the electric heater based on the result determined by the temperature determination unit 110.

[0092] 18 shows a flow chart of the heating process of the nozzle 40 according to the fourth embodiment. Note that the brazing process and the supply process of the brazing wire material 1 are the same as those in the first embodiment.

[0093] The control unit 101 acquires the temperature of the nozzle 40 (step S61), and then determines whether the acquired temperature is equal to or higher than a lower limit temperature (step S62).

[0094] In step S62, if the temperature of the nozzle 40 is below the lower limit (step S62; No), the automatic brazing apparatus 100 heats the nozzle 40 until the temperature reaches or exceeds the lower limit temperature (step S63).

[0095] In step S63, the automatic brazing apparatus 100 applies current from the regulator to the electric heater 60 to heat the nozzle 40. After step S63, the process returns to step S61.

[0096] In step S62, if the temperature of the nozzle 40 is equal to or higher than the lower limit (step S62; Yes), the control unit 101 determines whether the temperature of the nozzle 40 is equal to or lower than the upper limit temperature (step S64).

[0097] If the temperature of the nozzle 40 is higher than the upper limit (step S64; No), the automatic brazing apparatus 100 causes the nozzle 40 to radiate heat until the temperature becomes equal to or lower than the upper limit (step S65). In the nozzle heat radiation process, no current flows from the regulator to the electric heater 60, and heating is turned off. After the process of step S65, the process returns to step S61. If the temperature of the nozzle 40 is equal to or lower than the upper limit (step S64; Yes), the process ends.

[0098] By performing steps S61 to S65, the nozzle 40 can perform brazing at a temperature close to the range between the upper limit temperature and the lower limit temperature.

[0099] According to the configuration of the fourth embodiment, the temperature of the nozzle 40 can be accurately controlled electrically, instead of by a high-temperature flame as in the first to third embodiments, and therefore the brazing quality is further improved.

[0100] Embodiment 5. In the first to third embodiments, the flame 29 from the torch 28 is used to heat the nozzle 40. Alternatively, as shown in Fig. 19, an induction heating coil 62 may be used to heat the nozzle 40. When an alternating current is applied from a power source (not shown) to the induction heating coil 62, a magnetic field is generated. When the nozzle 40, which is made of metal, is placed in this magnetic field, the nozzle 40 is heated by electromagnetic induction.

[0101] 19 is the range of influence of the flame, the induction heating coil 62 may break down if it is affected by the flame, so it needs to be installed at a position away from A. Also, since it is preferable for the temperature sensor 41 to acquire the nozzle tip temperature, that is, the temperature at a position close to the tip of the wire brazing material 1, it is better to install the temperature sensor 41 closer to the nozzle tip than the induction heating coil 62.

[0102] In the block diagram of the automatic brazing apparatus 100 according to the fifth embodiment, the electric heater 60 in FIG. 17 becomes an induction heating coil 62, and the electric heater control unit 61 becomes an induction heating coil control unit.

[0103] A flow chart of the heating process of the nozzle 40 according to the fifth embodiment will be described with reference to Fig. 18. Note that the brazing process and the supply process of the brazing wire material 1 are the same as those in the first embodiment.

[0104] Steps S61, S62, and S64 are the same as those in the fourth embodiment, but the processes in steps S63 and S65 are different, and therefore only those steps will be explained.

[0105] In the nozzle heating process in step S63, an AC current is applied from the power supply to the induction heating coil 62 to heat the nozzle 40. In the nozzle heat dissipation process in step S65, the AC current is not applied from the power supply to the induction heating coil 62, and heating is turned off.

[0106] According to the configuration of the fifth embodiment, the temperature of the nozzle 40 can be accurately controlled electrically, instead of by a high-temperature flame as in the first to third embodiments, and therefore the brazing quality is further improved.

[0107] While the present disclosure has been described above based on the embodiments, the present disclosure is not limited to the above-described embodiments and modifications, and various modifications and applications are possible.

[0108] In each of the above-described embodiments, the cylinder mechanism uses the torch cylinder 27 and the electric cylinder 80. Alternatively, the torches 28, 78 may be moved to two or multiple positions by a drive device using, for example, a servo motor.

[0109] The workpiece heating mechanism 70 may be a mechanism that moves up and down, a positioning mechanism such as a robot, or a mechanism in which the workpiece W moves to approach the torch 78. In addition, when the workpiece heating mechanism 70 is a positioning mechanism such as a robot, it may heat another workpiece W located in a different position.

[0110] In the third embodiment, the nozzle cylinder 90 and the torch cylinder 27 are controlled at two positions, an advanced position and a retreated position, by air cylinders. Alternatively, position control at multiple points by electric cylinders may be used.

[0111] As described above, the automatic brazing apparatus 100 and the automatic brazing method are not limited to the above-described embodiment, and various modifications and substitutions can be made. Various embodiments of the present disclosure will be described below as appendices.

[0112] (Appendix 1) A work heating unit that heats a brazing portion of the work; A workpiece heating and moving unit that moves the workpiece heating unit relative to the brazing location; A nozzle through which a brazing wire passes toward the brazing portion; A nozzle heating unit that heats the nozzle; A temperature measuring unit for measuring a temperature of the nozzle; a temperature determination unit that determines a measured temperature of the nozzle measured by the temperature measurement unit against a preset temperature; A nozzle heating control unit that controls heating of the nozzle based on the result determined by the temperature determination unit. Automatic brazing equipment.

[0113] (Appendix 2) A nozzle heating moving unit that moves the nozzle heating unit; A nozzle heating and moving control unit that controls the operation of the nozzle heating and moving unit based on the result determined by the temperature determination unit. 2. An automatic brazing apparatus according to claim 1.

[0114] (Appendix 3) the nozzle heating moving unit includes a multi-point moving mechanism that moves the nozzle heating unit to three or more positions; The temperature determination unit determines a temperature difference between a preset temperature and the measured temperature, The nozzle heating movement control unit controls an operation of the nozzle heating movement unit based on the temperature difference. 3. An automatic brazing apparatus as described in appendix 2.

[0115] (Appendix 4) A nozzle moving unit that moves the nozzle is further provided, The nozzle heating unit heats the workpiece in addition to heating the nozzle. 4. The automatic brazing apparatus according to any one of claims 1 to 3.

[0116] (Appendix 5) Further comprising a fuel supply unit that supplies the same fuel to the workpiece heating unit and the nozzle heating unit. 5. The automatic brazing apparatus according to any one of claims 1 to 4.

[0117] (Appendix 6) The nozzle heating unit includes a flow rate control unit. 6. The automatic brazing apparatus according to any one of claims 1 to 5.

[0118] (Appendix 7) The nozzle heating unit includes an electric heater. 2. An automatic brazing apparatus according to claim 1.

[0119] (Appendix 8) The nozzle heating unit includes an induction heater. 2. An automatic brazing apparatus according to claim 1.

[0120] (Appendix 9) A work heating unit that heats a brazing portion of the work; A workpiece heating and moving unit that moves the workpiece heating unit relative to the brazing location; A nozzle through which a brazing wire passes toward the brazing portion; A nozzle heating unit that heats the nozzle; and a temperature measuring unit for measuring a temperature of the nozzle. a temperature determination step of determining a measured temperature of the nozzle relative to a preset temperature; A nozzle heating control step of controlling heating of the nozzle based on a result determined in the temperature determination step. Automatic brazing method.

[0121] (Appendix 10) A nozzle heating movement control step of controlling an operation of the nozzle heating unit is further provided. The automatic brazing apparatus comprises: A nozzle heating moving unit that moves the nozzle heating unit; A nozzle heating movement control unit that controls the operation of the nozzle heating movement unit based on the result determined in the temperature determination step. 10. The automated brazing method according to claim 9.

[0122] (Appendix 11) A nozzle moving unit that moves the nozzle is further provided, The nozzle heating movement control step includes a first movement control step for heating the workpiece and a second movement control step for heating the nozzle, In the first movement control step and the second movement control step, operations of the nozzle heating movement unit and the nozzle movement unit are controlled based on a result of the determination in the temperature determination step, respectively. 11. The automated brazing method of claim 10.

[0123] Various embodiments and modifications of the present disclosure are possible without departing from the broad spirit and scope of the present disclosure. The above-described embodiments are for explaining the present disclosure and do not limit the scope of the present disclosure. That is, the scope of the present disclosure is indicated by the claims, not the embodiments. Various modifications made within the scope of the claims and the scope of the disclosure equivalent thereto are considered to be within the scope of the present disclosure.

[0124] This application is based on Japanese Patent Application No. 2022-151195 filed on September 22, 2022. The entire specification, claims, and drawings of Japanese Patent Application No. 2022-151195 are incorporated herein by reference. [Industrial Applicability]

[0125] The present disclosure may be suitably employed, for example, in the manufacture of heat exchangers. [Explanation of symbols]

[0126] 1 wire brazing material, 1a coil material, 10 positioning mechanism, 11 arm, 11a tip, 20 nozzle heating mechanism, 21a, 21b flow control device (flow control section), 22 gas mixer, 23 branch pipe, 24a, 24b hose, 25, 25a, 25b, 25c hose (fuel supply section), 27 torch cylinder (nozzle heating movement section), 28 torch (nozzle heating section), 29 flame, 30 brazing material supply mechanism, 31 roller, 40 nozzle, 41 temperature sensor (temperature measurement section), 42 temperature recorder, 50 fixture, 60 electric heater, 61 electric heater control section, 62 induction heating coil (induction heating heater), 70 work heating mechanism, 77 torch cylinder (work heating movement section), 78 torch (work heating section), 79 flame, 80 Electric cylinder (multi-point movement mechanism), 90 nozzle cylinder (nozzle movement section), 100 automatic brazing device, 101 control section, 110 temperature determination section, 120 torch cylinder control section (nozzle heating movement control section), 120a electric cylinder control section, 120b nozzle cylinder control section, 130 brazing material supply mechanism control section, 140 positioning mechanism control section, 150 flow control device control section, 160 heating mechanism control section (nozzle heating control section), 170 storage device, W work.

Claims

1. A work heating unit that heats a brazing portion of the work; A workpiece heating and moving unit that moves the workpiece heating unit relative to the brazing location; A nozzle through which a brazing wire passes toward the brazing portion; A nozzle heating unit that heats the nozzle; A temperature measuring unit for measuring a temperature of the nozzle; a temperature determination unit that determines a measured temperature of the nozzle measured by the temperature measurement unit against a preset temperature; A nozzle heating control unit that controls heating of the nozzle based on the result determined by the temperature determination unit. Automatic brazing equipment.

2. A nozzle heating moving unit that moves the nozzle heating unit; A nozzle heating and moving control unit that controls the operation of the nozzle heating and moving unit based on the result determined by the temperature determination unit.

2. The automatic brazing apparatus of claim 1.

3. the nozzle heating moving unit includes a multi-point moving mechanism that moves the nozzle heating unit to three or more positions; The temperature determination unit determines a temperature difference between a preset temperature and the measured temperature, The nozzle heating movement control unit controls an operation of the nozzle heating movement unit based on the temperature difference.

3. The automatic brazing apparatus according to claim 2.

4. A nozzle moving unit that moves the nozzle is further provided, The nozzle heating unit heats the workpiece in addition to heating the nozzle.

4. An automatic brazing apparatus according to claim 1.

5. Further comprising a fuel supply unit that supplies the same fuel to the workpiece heating unit and the nozzle heating unit.

4. An automatic brazing apparatus according to claim 1.

6. The nozzle heating unit includes a flow rate control unit.

4. An automatic brazing apparatus according to claim 1.

7. The nozzle heating unit includes an electric heater.

2. The automatic brazing apparatus of claim 1.

8. The nozzle heating unit includes an induction heater.

2. The automatic brazing apparatus of claim 1.

9. A work heating unit that heats a brazing portion of the work; A workpiece heating and moving unit that moves the workpiece heating unit relative to the brazing location; A nozzle through which a brazing wire passes toward the brazing portion; A nozzle heating unit that heats the nozzle; and a temperature measuring unit for measuring a temperature of the nozzle. a temperature determination step of determining a measured temperature of the nozzle relative to a preset temperature; A nozzle heating control step of controlling heating of the nozzle based on a result determined in the temperature determination step. Automatic brazing method.

10. A nozzle heating movement control step of controlling an operation of the nozzle heating unit is further provided. The automatic brazing apparatus comprises: A nozzle heating moving unit that moves the nozzle heating unit; A nozzle heating movement control unit that controls the operation of the nozzle heating movement unit based on the result determined in the temperature determination step.

10. The automated brazing method of claim 9.

11. A nozzle moving unit that moves the nozzle is further provided, The nozzle heating movement control step includes a first movement control step for heating the workpiece and a second movement control step for heating the nozzle, in the first movement control step and the second movement control step, operations of the nozzle heating movement unit and the nozzle movement unit are controlled based on a result of the determination in the temperature determination step, respectively. The automated brazing method of claim 10.

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