JP2023147697A - Friction stirring joining device and friction stirring joining method - Google Patents

Abstract

To provide a friction stirring joining device that can optimally hold an advancing speed or a rotating speed of a joining tool, in accordance with a temperature of joining.SOLUTION: A friction stirring joining device performs friction stirring joining of a member to be joined, by inserting a joining tool into the member to be joined, up to a target depth, while rotating the tool at a target rotating speed, softening an inserted portion of the member to be joined and the vicinity of the inserted portion and advancing the joining tool along a join-line showing a site at which the member to be joined is subjected to friction stirring joining. When performing friction stirring joining of the member to be joined while advancing the joining tool in a joining direction, the friction stirring joining device controls at least either of an advancing speed and a rotating speed of the joining tool, on the basis of a value of a temperature of joining showing a temperature in the vicinity of the inserted portion including a portion just below the join-line.SELECTED DRAWING: Figure 2

Description

The present invention relates to the configuration and control of a friction stir welding apparatus for joining workpieces together by friction stir welding, and is particularly applicable to joining workpieces that require high-quality (high-precision) joining. Concerning effective techniques.

Friction stir welding (FSW) is a process in which materials to be joined are joined together by softening the materials to be welded using frictional heat generated by rotating a cylindrical welding tool and stirring that part. Since no material is used, the fatigue strength is high, and since the material does not melt, it is possible to join with little welding deformation (strain), and it is expected to be applied in a wide range of fields, such as aircraft and automobile bodies.

As background technology in this technical field, there is a technology such as that disclosed in Patent Document 1, for example. Patent Document 1 states, ``A reaction force detection sensor directly connected to a welding tool (equivalent to a probe-type rotary tool) is used to detect when the welding tool is attached to the workpiece (workpiece) during the welding operation of the welding tool. A method for controlling rotary tools for friction stir welding in which the reaction force (reaction force) received from has been done.

Specifically, in the stage before starting operation, the maximum advancing speed that can maintain good joint quality (equivalent to the joint surface) is determined, the corresponding reaction force is set as a reference value, and in the stage of operation, the obtained The advancing speed of the welding tool is controlled so that the current value of the reaction force obtained approaches the reference value.

Japanese Patent Application Publication No. 2004-50234

However, the method for controlling the advancing speed of the welding tool disclosed in Patent Document 1 does not take into account the welding temperature, which indicates the temperature near the insertion portion where the welding tool is inserted into the workpiece. Therefore, it is not always possible to maintain good bonding quality.

In friction stir welding, the welding tool is inserted into the workpiece to a predetermined insertion depth while rotating at a predetermined rotational speed, heat input treatment is performed until good welding quality can be maintained, and the welding tool is rotated at a predetermined insertion depth along the welding line. Proceed at the speed of progress. The bonding temperature is not constant because it is affected by the heat input from the parts that have already been bonded and accumulates heat. The advancing speed or rotational speed of the welding tool must be controlled in consideration of this temperature fluctuation.

In Patent Document 1, the maximum advancing speed of the welding tool that can maintain the welding quality is determined, and the reaction force from the welded members against the welding tool at that time is measured and set as a reference value. The current value is acquired and the advancing speed of the welding tool is controlled so that the value approaches the reference value. The reaction force is affected by bonding temperature fluctuations and is not constant. In other words, when the welding temperature changes between the welding start position and the welding end position using the welding tool, the reaction force (load) also changes due to the change in the welding temperature. This variation has not been taken into account.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a friction stir welding apparatus and a friction stir welding method that can optimally maintain the advancing speed or rotational speed of a welding tool in accordance with the welding temperature.

In order to solve the above problems, the present invention inserts a welding tool into the welded members to a target depth while rotating at a target rotation speed, softens the insertion portion of the welded members and the vicinity thereof, and A friction stir welding apparatus for friction stir welding the welded members by advancing the welding tool along a welding line indicating a part to be friction stir welded, the friction stir welding apparatus comprising: When friction stir welding the members to be welded while progressing, at least the advancing speed and rotational speed of the welding tool are determined based on a welding temperature value indicating the temperature in the vicinity of the insertion portion including directly below the welding line. It is characterized by controlling either.

Further, the present invention provides a method for (a) performing test welding a predetermined number of times before friction stir welding the welded members using a welding tool, and friction stir welding the welded members on a mounting table on which the welded members are placed. (b) arranging one or more parts on the mounting table immediately below the joining line for each divided section divided in step (a); acquiring a predetermined number of welding temperature lower limit values, upper limit values, and temperature ranges for each of the divided sections, which indicate the temperature near the welding tool at which desired friction stir welding is possible, using the installed temperature sensor, and set them as a reference welding temperature; , (c) In parallel with step (b), a predetermined number of advancing speeds of the welding tool are acquired and set as a reference advancing speed, and a predetermined number of rotational speeds of the welding tool at that time are acquired and set as a reference. (d) when friction stir welding the members to be welded, obtaining the current welding temperature by the temperature sensor for each of the divided sections, and setting the current welding temperature for each of the divided sections; Select the reference junction temperature to which the current junction temperature belongs, and set the reference advancement speed corresponding to the selected reference junction temperature as the target value of the advancement speed, and/or The method is characterized in that it includes the step of setting the corresponding reference rotation speed as a target value of the rotation speed.

The present invention also provides a method for (a) performing test welding prior to friction stir welding of members to be welded using a welding tool, and performing friction stir welding of the members to be welded on a mounting table on which the members to be welded are placed. dividing a joining line indicating a plurality of sections at predetermined intervals into a plurality of sections, (b) disposing one or more sections on the mounting table immediately below the joining line for each divided section divided in step (a); (c) in parallel with step (b), acquiring a welding temperature indicating the temperature near the welding tool at which desired friction stir welding is possible using a temperature sensor for each divided section and setting it as a reference welding temperature; , obtaining the advancing speed of the welding tool and setting it as a reference advancing speed, and obtaining the rotational speed of the welding tool at that time and setting it as the reference rotational speed; (d) friction stirring the welded members; When joining, the step includes the step of setting the reference advancing speed as a target value of the advancing speed for each of the divided sections, and/or setting the reference rotational speed as the target value of the rotational speed. It is characterized by

According to the present invention, it is possible to realize a friction stir welding apparatus and a friction stir welding method that can optimally maintain the advancing speed or rotational speed of a welding tool in accordance with the welding temperature.

This enables high-quality (high-precision) friction stir welding of the members to be joined.

Problems, configurations, and effects other than those described above will be made clear by the following description of the embodiments.

1 is a diagram showing an overall outline of a friction stir welding apparatus according to Example 1 of the present invention. FIG. 2 is a perspective view showing a specific example of the mounting table and temperature sensor of FIG. 1; FIG. 3 is a diagram showing a joining line and a dividing section according to Example 1 of the present invention. FIG. 3 is a diagram showing the correlation between a reference bonding temperature, a reference advancement speed, and a reference rotation speed according to Example 1 of the present invention. FIG. 3 is a diagram conceptually showing the relationship between the spindle motor load factor and the welding tool insertion operation. It is a flowchart which shows the friction stir welding method using the target value setting method of the advancing speed and rotational speed of the welding tool based on Example 3 of this invention. 12 is a flowchart showing a friction stir welding method using a method for setting target values for the advancing speed and rotational speed of a welding tool according to Example 4 of the present invention. It is a figure showing the whole outline of a friction stir welding device concerning Example 5 of the present invention. FIG. 8A is a view taken along the line A-A' in FIG. 8A.

Embodiments of the present invention will be described below with reference to the drawings. Note that in each drawing, the same components are denoted by the same reference numerals, and detailed explanations of overlapping parts will be omitted.

EMBODIMENT OF THE INVENTION With reference to FIGS. 1-5, the friction stir welding apparatus and friction stir welding method based on Example 1 of this invention are demonstrated.

FIG. 1 is a diagram showing an overall outline of a friction stir welding apparatus 1 according to this embodiment.

As shown in FIG. 1, the friction stir welding apparatus 1 of this embodiment has, as main components, an apparatus main body 2 and a main shaft support part 4 connected to the apparatus main body 2 via a Z-axis vertical movement drive mechanism part 3. , a main shaft 15 held by the main shaft support 4, a tool holder (welding head) 5 held by the main shaft 15, and a joining tool 6 held by the tool holder (welding head) 5. There is.

As illustrated in FIG. 1, the Z-axis vertical movement drive mechanism 3 uses, for example, a ball screw, a linear guide, etc. Drive in the axial direction (vertical direction).

The welding tool 6 includes a shoulder portion 7 and a probe portion (joint pin) 8, and is connected to a main shaft motor 14 (directly connected in FIG. 1). The main shaft motor 14 rotates the welding tool 6 in a predetermined direction.

The device main body 2 supports a main shaft support portion 4 via a Z-axis vertical movement drive mechanism 3, and provides a drive signal to the main shaft motor 14 from a control section (control device) 11 mounted on (attached to) the device main body 2. The welding tool 6 is advanced along the welding line while rotating. In other words, the device main body 2 holds the spindle support part 4, the spindle 15, and the tool holder (welding head) 5, rotates the welding tool 6, and rotates the welding tool 6 in the X-axis direction and Z-axis direction in FIG. move it to

While rotating the welding tool 6 at a predetermined rotation speed, the shoulder portion 7 and the probe portion 8 are pressed onto the welding line on the surface of the workpieces 9 (9a, 9b) placed on the mounting table 10, thereby generating frictional heat. is generated to soften the welded member 9, the shoulder portion 7 and the probe portion 8 are inserted into the welded member 9 by the required amount, and by maintaining the rotation speed, plastic flow is generated and the inserted portion is agitated. . By pulling out or moving the welding tool 6, the stirring section (joint section) is cooled, and the members 9 to be welded are welded.

Note that FIG. 1 shows a configuration in which the tool holder (welding head) 5 and the welding tool 6 are connected (held) to the apparatus main body 2 via the main shaft 15, the main shaft support part 4, and the Z-axis vertical movement drive mechanism part 3. However, the present invention is not limited to this, and for example, a configuration in which the device is connected (held) to the device main body 2 only via the Z-axis vertical movement drive mechanism section 3, or a configuration in which the device main body 2 is connected to the device main body 2 via other movable means is possible. 2, a configuration in which the tool holder (welding head) 5 and the welding tool 6 are directly connected (held) to the apparatus main body 2, or a configuration in which the tool holder (welding head) 5 and the welding tool 6 are directly connected (held) to the apparatus main body 2, or the configuration shown in FIG. The present embodiment also includes a configuration in which a C-shaped frame is provided between the device body 2 and the device body 2, and a configuration in which the device body 2 is connected (held) to the device body 2 having a multi-axis robot arm.

Further, the welding tool may have the same shoulder portion 7 and the probe portion (joint pin) 8 (that is, only the shoulder without a probe), or may have a structure in which the shoulder portion 7 does not rotate. good.

A control section (control device) 11 that controls the operation of the friction stir welding apparatus 1 is installed (attached) to the apparatus main body 2 . The control unit (control device) 11 controls welding condition signals that determine the welding conditions for the welding tool 6 and the vertical direction (Z direction) holding position of the welding tool 6 (insertion of the welding pin 8) by the Z-axis vertical movement drive mechanism 3. A storage unit (not shown) is provided for storing bonding parameters (FSW bonding conditions) such as a holding position determination signal that determines the holding position determination signal (FSW bonding amount). Note that the control unit 11 may be configured as a control device separately from the main body of the apparatus.

The device main body 2 is also provided with an X-axis longitudinal drive mechanism section 12 that can be driven in the X-axis direction, and an X-axis longitudinal drive motor 13 drives the upper part of the device main body 2 into a linear By moving along the rail of the guide, the tool holder (joining head) 5 and the joining tool 6 can be moved in the X-axis direction (joining direction).

Here, in the friction stir welding apparatus 1 of this embodiment, as shown in FIG. It is arranged. A plurality of temperature sensors 17 are arranged in the X-axis direction so that the welding temperature at any location in the X-axis direction can be measured along the welding line during friction stir welding.

The welding temperature information acquired by the temperature sensor 17 is input to the control unit (control device) 11 and fed back to the welding conditions for friction stir welding by the welding tool 6.

FIG. 2 shows a specific example of the mounting table 10 and the temperature sensor 17. FIG. 2 shows, as an example of the configuration of the mounting table 10, a mounting table having a structure in which the members to be joined 9 (9a, 9b) can be moved in the X-axis direction by a mounting table moving mechanism section 10a.

As described above, a plurality of temperature sensors 17 (here, five, n1 to n5) are arranged in the X-axis direction on the mounting table 10, and the It is possible to measure the junction temperature at any location in the axial direction.

In the present invention, as described later, the speed of movement of the welding tool 6 (shoulder portion 7 and probe portion 8) in the X-axis direction with respect to the welded members 9 (9a, 9b) is determined based on the welding temperature information acquired by the temperature sensor 17. and the rotation speed.

Next, the relationship between the spindle motor load factor and the welding tool insertion operation will be described using FIG. 5. FIG. 5 is a diagram conceptually showing the relationship between the spindle motor load factor and the welding tool insertion operation. As shown in FIG. 5, the welding tool position is related to the load factor of the spindle motor 14.

When the probe portion (welding pin) 8 is brought into contact with the workpiece 9 and insertion of the welding tool 6 is started, the load factor of the main shaft motor 14 increases as the position of the welding tool becomes deeper.

If the shoulder portion 7 comes into contact with the workpiece 9 during insertion of the welding tool 6, the rate of increase in the load factor of the main shaft motor 14 will temporarily decrease; The rate of increase in the load factor increases again.

When the target load rate or the target welding tool position during insertion of the welding tool 6 is reached, the insertion process of the welding tool 6 is finished, and the welding tool 6 is rotated for a certain period of time with the welding tool position fixed. Heat input treatment to the members 9 to be joined is performed.

Thereafter, friction stir welding processing of the members 9 to be welded is performed. During the friction stir welding process, the driving of the main shaft motor 14 and the Z-axis vertical movement drive motor 16 is controlled so that both the main shaft motor load factor and the welding tool position are maintained at constant values (target values).

When the welding tool 6 is started to be withdrawn at the end of the friction stir welding process, the load factor of the main shaft motor 14 decreases as the welding tool position becomes shallower.

As described above, the friction stir welding apparatus 1 of the present embodiment is configured to apply a target depth to the welded members 9 (9a, 9b) while rotating the welding tool 6 at a target rotational speed indicating a predetermined rotational speed. It is inserted to the depth, and at that position, heat input treatment is performed until the welding temperature, which indicates the temperature of the welded members 9 near the welding tool 6, rises to a desired value. The welding tool 6 is advanced at a target advancement speed indicating a predetermined advancement speed to the friction stir welding end position over the welded parts 9 (9a, 9b) to be welded by friction stir welding.

In friction stir welding, welding parts 9 are friction stir welded by rotating the welding tool 6 to soften the insertion part of the welding tool 6 and its vicinity, and the friction stir welding is performed to weld the parts 9 to be welded. is an important element. Therefore, in order to ensure the desired friction stir welding quality, it is important to appropriately manage the frictional heat, that is, the welding temperature.

Conventional friction stir welding equipment sets the target rotational speed and advancement speed of the welding tool to initial values based on welding conditions based on the material and thickness of the welded parts, regardless of fluctuations in welding temperature. Accordingly, operations have been carried out in which the friction stir welding is held constant from the friction stir welding start position to the friction stir welding end position without changing.

This does not pose a particular problem if the welded members are thick and variations in friction stir welding quality due to slight fluctuations in welding temperature can be ignored. However, when the welded parts are thin aluminum sheets used for the purpose of reducing the weight of vehicles such as electric vehicles, variations in friction stir welding quality due to fluctuations in welding temperature may become a problem. There is. The present invention solves this problem.

The level of frictional heat, that is, the level of welding temperature, is determined by the rotational speed and/or advancing speed of the welding tool.

For example, even if the rotation speed is constant, the joining temperature will increase if the advancing speed is slowed, and even if the advancing speed is constant, the joining temperature will increase even if the rotating speed is increased. Conversely, even if the rotational speed is constant, the bonding temperature will decrease if the advancing speed is increased, and even if the rotational speed is constant, the bonding temperature will decrease even if the rotational speed is decreased.

Therefore, in order to control the bonding temperature, it is necessary to control the rotation speed and/or advancement speed of the bonding tool. In other words, in order to ensure the desired friction stir welding quality, it is necessary to control the rotational speed and/or advancement speed of the welding tool so that the welding temperature can be appropriately controlled.

Therefore, in the present invention, target values for the rotational speed and advancing speed of the welding tool 6 are set and managed.

FIG. 3 shows the joining line 18 for friction stir welding and divided sections obtained by dividing the joining line 18 into a plurality of sections at predetermined intervals. In addition, in FIG. 3, illustration of the members 9 (9a, 9b) to be joined is omitted for easy understanding.

First, as shown in FIG. 3, the joining line 18 is divided into a plurality of sections (here, seven sections from division section 1 to division section 7) at predetermined intervals. Target values for the rotational speed and advancing speed of the welding tool 6 are set for each divided section. The setting method will be explained in detail.

Before the actual welding of the members 9 to be welded by the friction stir welding apparatus 1, test welding is performed. In test welding, a lower limit value and an upper limit value that define a range of welding temperatures that can ensure the desired friction stir welding quality are measured for each divided section under each welding condition (rotational speed and advancing speed). Furthermore, the rotational speed and advancing speed of the welding tool 6 at that time are measured.

These welding temperature range, the value of the rotational speed of the welding tool 6, and the value of the advancement speed of the welding tool 6 are set as a reference welding temperature, a reference rotational speed, and a reference advancement speed.

This process is repeated a predetermined number of times, and a predetermined number of combinations of correlations between the reference bonding temperature, the reference advancing speed, and the reference rotational speed are set for each divided section, as shown in the correspondence table shown in FIG. The reason why a predetermined number of combinations of correlations are prepared is to cope with extremely small temperature changes and to ensure the highest precision friction stir welding quality.

In the actual welding using the friction stir welding apparatus 1, a current welding temperature indicating the current welding temperature is acquired for each divided section. Select the closest reference junction temperature to which the obtained current junction temperature belongs, select the reference rotation speed corresponding to the selected reference junction temperature as the target value of rotation speed, and select the reference progress corresponding to the selected reference junction temperature. Select speed as the target value for progress speed. Actually, it is determined whether to reset the target value of either the rotational speed or the advancing speed, or both of the target values, depending on the bonding temperature state at that time.

The actual welding of the friction stir welding apparatus 1 to which the present invention is applied will be specifically explained. The welding tool 6 is positioned at the friction stir welding start position, an initial target value of the rotational speed of the welding tool 6 is set, and the welding tool 6 is inserted into the workpiece 9 to the target depth while rotating the welding tool 6.

Heat input processing is performed at that position to obtain the current bonding temperature. In the divided section, select the reference welding temperature to which the current welding temperature belongs, set the reference advancing speed corresponding to the reference welding temperature as the target value of the advancing speed of the welding tool 6, and move the welding tool 6 along the welding line 18. Let it proceed.

When the welding tool 6 reaches the next divided section, the current welding temperature is obtained again, and in that divided section, the reference welding temperature to which the current welding temperature belongs is selected, and the reference progress speed corresponding to the reference welding temperature is set. This is reset as the target value for the tool 6 and the welding tool 6 continues to advance. Each time the welding tool 6 reaches the next divided section, this process is repeated to control the advancing speed and manage the welding temperature.

In addition, in the above example, a method was explained in which the rotational speed of the welding tool 6 is kept constant and the target value of the advancing speed is reset for each divided section, but it is also possible to set the target value of the rotational speed, or if necessary If so, target values for both the rotational speed and the advancing speed may be set.

The bonding temperature of each divided section (reference bonding temperature and current bonding temperature) is obtained using the temperature sensor 17 disposed on the mounting table 10 directly below the bonding line for each divided section, as shown in FIG. .

The temperature sensors 17 may be arranged at equal intervals just below the bonding line, but the spacing between the temperature sensors 17 may be set depending on the degree of variation in the bonding temperature. For example, as can be seen from FIG. 3, in the simple shape (straight portion) of the bonding line where the variation in bonding temperature is relatively small, the spacing between the temperature sensors 17 is increased, and the variation in bonding temperature is relatively large. In parts with complex shapes (curved parts, meandering curved parts, etc.), the intervals at which the temperature sensors 17 are arranged are reduced.

By arranging the temperature sensor 17 in this manner, it is possible to obtain the fluctuation state of the welding temperature with higher accuracy, and it is also possible to control the advancing speed and rotational speed of the welding tool 6 with higher precision.

In friction stir welding, heat input propagates outside the joint, affecting other joints and causing fluctuations in welding temperature. This is to cope with the fact that this influence becomes greater when the shape of the joining line 18 is complicated.

In addition, in this example, a predetermined number of combinations of the correlation between the reference welding temperature, the reference progress speed, and the reference rotation speed are prepared for each divided section, and the welding tool is used when pursuing the highest quality friction stir welding quality. Although the rotational speed control and advancing speed control of the welding tool 6 have been described, if the required friction stir welding quality is not the highest quality, the rotational speed and advancing speed of the welding tool 6 may be controlled by a simpler method. In the above explanation, the combination of the correlation between the reference welding temperature, reference advancing speed, and reference rotational speed was set for each divided section, but in the entire section from the friction stir welding start position to the friction stir welding end position, A combination of the same reference junction temperature, reference advancement speed, and reference rotational speed correlation is used.

In that case, the current junction temperature is acquired in each divided section, but the reference junction temperature to which the current junction temperature belongs and the corresponding reference advancement speed and reference rotation speed must be selected from among the combinations with the same correlation. become.

Furthermore, the temperature sensor 17 may be placed closer to either the AS (advancing side) or the RS (retreating side) instead of directly below the insertion part (joining line) of the welding tool 6. The reference value to be placed and used in both AS and RS may be selected for each divided section.

A friction stir welding method according to Example 2 of the present invention will be explained.

In Example 1, in order to respond to minute welding temperature fluctuations and ensure the highest precision friction stir welding quality, test welding was repeated a predetermined number of times, and a predetermined number of reference welding temperatures, reference advancement speeds, and reference rotations were set. Set a combination of speed correlations, select a reference welding temperature to which the current welding temperature belongs in each divided section, set the reference rotational speed corresponding to the reference welding temperature as the target value of the rotational speed of the welding tool 6, Although control has been shown in which the reference advancing speed corresponding to the reference welding temperature is selected as the target value of the advancing speed of the welding tool 6, a simpler advancing speed of the welding tool 6 may be selected depending on the accuracy of the required friction stir welding quality. The target value of the rotational speed and the target value of the advancing speed of the welding tool 6 may be set using a speed control method or a rotational speed control method.

The simple control method will be explained in detail. Prior to the actual welding, test welding was carried out to measure the welding temperature, rotational speed of the welding tool 6, and advancement speed of the welding tool 6 that ensured the desired friction stir welding quality for each divided section, and the respective standards were determined. Set as the bonding temperature, standard advancement speed, and standard rotation speed.

In the actual welding operation, when the welding tool 6 reaches each divided section, the reference rotation speed corresponding to the reached divided section is selected as the target value of the rotation speed of the welding tool 6, and the reference rotation speed corresponding to the reached divided section is selected. The advancing speed is selected as the target value of the advancing speed of the welding tool 6.

The actual operational connection will be specifically explained. The welding tool 6 is positioned at the friction stir welding start position, an initial target value of the rotational speed of the welding tool 6 is set, and the welding tool 6 is inserted into the workpiece 9 to the target depth while rotating the welding tool 6. Heat input treatment is performed at that position.

The standard advancing speed set in the divided section is selected and set as the target value of the advancing speed of the welding tool 6, and the welding tool 6 is caused to advance along the welding line 18.

When the welding tool 6 reaches the next divided section, the standard advancement speed set in that divided section is selected and set as the target value of the advancement speed of the welding tool 6, the welding tool 6 is advanced along the joining line 18, and the welding Continue progressing with tool 6. Each time the welding tool 6 reaches the next divided section, this process is repeated to control the advancing speed and manage the welding temperature.

In addition, although the example of setting the target value of the advancing speed was explained above, it is also possible to set the target value of the rotational speed, and if necessary, the target value of both the rotational speed and the advancing speed can be set. It's okay. In this control method, target values for the advancing speed and rotational speed of the welding tool 6 for each divided section are prepared as the only target values.

Even in this simple operational welding, by controlling the rotational speed and/or advancing speed of the welding tool 6, friction stirring is performed without controlling the welding temperature, with the rotational speed and advancing speed of the welding tool 6 kept at their initial values. The superiority over joint operation has been confirmed through experiments.

In this embodiment as well, the bonding temperature of each divided section is obtained using the temperature sensor 17 disposed on the mounting table 10 directly below the bonding line for each divided section.

With reference to FIG. 6, a friction stir welding method according to Example 3 of the present invention will be described.

FIG. 6 is a flowchart showing a friction stir welding method using the method of setting target values for the advancing speed and rotational speed of the welding tool 6 according to the present invention.

First, in step S601, the welding tool 6 performs test welding a predetermined number of times before the actual welding of the welded members 9, and the welded members 9 are friction stirred on the mounting table 10 on which the welded members 9 are placed. A joining line 18 indicating the parts to be joined is divided into a plurality of sections at predetermined intervals.

Next, in step S602, one or more temperature sensors 17 are disposed on the mounting table 10 directly below the welding line 18 for each of the divided sections divided in step S601, in the vicinity of the welding tool 6 where the desired stirring welding quality can be ensured. A predetermined number of lower limit values, upper limit values, and temperature ranges of the junction temperature indicating the temperature are obtained for each divided section and set as the reference junction temperature.

In parallel with step S602, in step S603, a predetermined number of advancing speeds of the welding tool 6 are acquired and set as a reference advancing speed, and a predetermined number of rotation speeds of the welding tool 6 at that time are acquired and set as the reference rotation speed. Set.

Finally, in step S604, in the main operation stage, the current junction temperature is acquired by the temperature sensor 17 for each divided section, and the reference junction temperature to which the current junction temperature belongs is selected for each divided section. , a reference advancing speed corresponding to the selected reference joining temperature is set as a target value of the advancing speed, and/or a reference rotational speed corresponding to the selected reference joining temperature is set as a target value of the rotational speed.

With reference to FIG. 7, a friction stir welding method according to Example 4 of the present invention will be described.

FIG. 7 is a flowchart showing a friction stir welding method using the method of setting target values for the advancing speed and rotational speed of the welding tool 6 according to the present invention.

First, in step S701, the welding tool 6 performs test welding of the welded members 9 prior to the actual welding, and the welded members 9 are friction stir welded on the mounting table 10 on which the welded members 9 are placed. The joining line 18 indicating the part is divided into a plurality of sections at predetermined intervals.

Next, in step S702, one or more temperature sensors 17 are disposed on the mounting table 10 directly below the welding line 18 for each of the divided sections divided in step S701, in the vicinity of the welding tool 6 where the desired stirring welding quality can be ensured. The junction temperature indicating the temperature is obtained for each divided section and set as the reference junction temperature.

In parallel with step S702, in step S703, the advancing speed of the welding tool 6 is obtained and set as the reference advancing speed, and the rotational speed of the welding tool 6 at that time is obtained and set as the reference rotating speed.

Finally, in step S704, in the main operation stage, a reference traveling speed is set as a target value of the traveling speed and/or a reference rotational speed is set as a target value of the rotational speed for each divided section.

A friction stir welding apparatus according to Example 5 of the present invention will be described with reference to FIGS. 8A and 8B.

FIG. 8A is a diagram showing an overall outline of the friction stir welding apparatus 1 according to this embodiment. FIG. 8B is a view taken along the line A-A' in FIG. 8A.

In the first embodiment (FIGS. 1 and 2), an example was explained in which the temperature sensor 17 is disposed on the mounting table 10, but as shown in FIGS. 8A and 8B, the non-contact temperature sensor 20 (20a, 20b) may be installed in the device main body 2 and the bonding temperature may be measured without contact.

In the case of a non-contact temperature sensor, the temperature sensor can be installed in an existing friction stir welding apparatus relatively easily.

Note that the present invention is not limited to the embodiments described above, and includes various modifications. For example, the embodiments described above are described in detail to explain the present invention in an easy-to-understand manner, and the present invention is not necessarily limited to having all the configurations described. Furthermore, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace some of the configurations of each embodiment with other configurations.

DESCRIPTION OF SYMBOLS 1...Friction stir welding device, 2...Device main body, 3...Z-axis vertical movement drive mechanism, 4...Spindle support part, 5...Tool holder (welding head), 6...Welding tool, 7...Shoulder part, 8...Probe part (joining pin), 9, 9a, 9b... member to be joined, 10... mounting table, 10a... mounting table moving mechanism section, 11... control section (control device), 12... X-axis longitudinal drive mechanism section, 13... X Axis longitudinal drive motor, 14...Main shaft motor, 15...Main shaft, 16...Z-axis vertical drive motor, 17...Temperature sensor, 18...Joining line, 19...(Temperature sensor) gripping mechanism, 20, 20a, 20b...Non Contact temperature sensor.

In order to solve the above problems, the present invention inserts a welding tool into the welded members to a target depth while rotating at a target rotation speed, softens the insertion portion of the welded members and the vicinity thereof, and A friction stir welding apparatus for friction stir welding the welded members by advancing the welding tool along a welding line indicating a part to be friction stir welded, the friction stir welding apparatus comprising: When friction stir welding the members to be welded while progressing, at least the advancing speed and rotational speed of the welding tool are determined based on a welding temperature value indicating the temperature in the vicinity of the insertion portion including directly below the welding line. the welding tool, the welding tool divides the welded parts from the position where friction stir welding starts to the position where friction stir welding ends into a plurality of parts at predetermined intervals, and divides the parts to indicate each divided section. The target value of the advancing speed for each of the divided sections is set according to a standard advancing speed that is set corresponding to the standard joining temperature that is set for each section, and the target value of the advancing speed is set according to the standard rotating speed that is set corresponding to the standard joining temperature. The method is characterized in that a target value of the rotational speed is set for each of the divided sections .

Claims (9)

The welding tool is inserted into the welded members to the target depth while rotating at a target rotational speed, softens the insertion portion of the welded members and the vicinity thereof, and moves the welded members along the welding line indicating the area to be friction stir welded. A friction stir welding apparatus for friction stir welding the members to be welded by advancing the welding tool by moving the welding tool,
The friction stir welding apparatus is configured to perform friction stir welding of the members to be welded while the welding tool moves in the welding direction, based on a welding temperature value indicating the temperature near the insertion portion including directly below the welding line. A friction stir welding apparatus characterized in that at least one of a traveling speed and a rotational speed of the welding tool is controlled. The friction stir welding apparatus according to claim 1,
The friction stir welding apparatus divides the to-be-welded members into a plurality of sections at predetermined intervals from a position where friction stir welding is started to a position where friction stir welding ends using the welding tool, and each divided section is indicated. The target value of the advancing speed for each of the divided sections is set according to the standard advancing speed that is set corresponding to the reference joining temperature that is set for each divided section, and the reference rotation speed is set corresponding to the reference joining temperature. A friction stir welding apparatus characterized in that the target value of the rotational speed for each of the divided sections is set by: The friction stir welding apparatus according to claim 2,
The friction stir welding apparatus measures a lower limit value and an upper limit value of the welding temperature at which desired friction stir welding can be performed for each divided section during test welding before friction stir welding the welded members. and setting that temperature range as the reference joining temperature, measuring the advancing speed at that time and setting it as the reference advancing speed, and measuring the rotational speed at that time and setting it as the reference rotating speed. A friction stir welding device characterized by: The friction stir welding apparatus according to claim 3,
The friction stir welding apparatus repeats the test welding a predetermined number of times, prepares a predetermined number of combinations of correlations between the reference welding temperature, the reference advancement speed, and the reference rotational speed, and friction stir welds the welded members. A friction stir welding apparatus characterized in that, at times, a reference welding temperature to which the acquired welding temperature belongs is selected, and the reference advancement speed and reference rotational speed corresponding thereto are selected. The friction stir welding apparatus according to claim 2,
The friction stir welding apparatus measures the welding temperature at which desired friction stir welding is possible for each divided section during test welding before friction stir welding the welded members, and sets the welding temperature as the reference welding temperature. A friction stir welding apparatus characterized in that the speed of rotation at that time is measured and set as the reference speed. The friction stir welding apparatus according to claim 5,
The friction stir welding apparatus selects the standard advancing speed set for each of the divided sections as the target value of the advancing speed when friction stir welding the members to be welded, and A friction stir welding apparatus characterized in that the set reference rotational speed is selected as the target value of the rotational speed. The friction stir welding apparatus according to any one of claims 2 to 6,
The friction stir welding apparatus acquires the welding temperature by one or more temperature sensors disposed for each of the divided sections directly below the welding line on a mounting table on which the members to be welded are placed. Features of friction stir welding equipment. A friction stir welding method comprising the following steps;
(a) Test welding is performed a predetermined number of times before friction stir welding the welded members using a welding tool, and a welding line indicating the area where the welded members are friction stir welded on a mounting table on which the welded members are placed. dividing into a plurality of sections at predetermined intervals;
(b) Temperature in the vicinity of the welding tool at which desired friction stir welding is possible using one or more temperature sensors disposed on the mounting table immediately below the welding line for each divided section divided in step (a) above. acquiring a predetermined number of lower limit values, upper limit values, and temperature ranges of the junction temperatures indicating the above for each of the divided sections, and setting them as a reference junction temperature;
(c) In parallel with step (b) above, a predetermined number of advancing speeds of the welding tool are acquired and set as a reference advancing speed, and a predetermined number of rotational speeds of the welding tool at that time are acquired and the reference rotation speed is set. Step to set as speed,
(d) When performing friction stir welding of the members to be welded, the current welding temperature is acquired by the temperature sensor for each of the divided sections, and the current welding temperature is acquired for each of the divided sections to which the current welding temperature belongs. selecting a reference junction temperature and setting the reference traveling speed corresponding to the selected reference joining temperature as a target value of the traveling speed; and/or setting the reference rotational speed corresponding to the selected reference joining temperature. a step of setting the rotational speed as a target value; A friction stir welding method comprising the following steps;
(a) Perform test welding before friction stir welding the welded members using a welding tool, and predetermine a welding line indicating the area where the welded members will be friction stir welded on a mounting table on which the welded members are placed. a step of dividing into multiple intervals with an interval of
(b) Temperature in the vicinity of the welding tool at which desired friction stir welding is possible using one or more temperature sensors disposed on the mounting table immediately below the welding line for each divided section divided in step (a) above. obtaining a junction temperature representing each of the divided sections and setting it as a reference junction temperature;
(c) In parallel with step (b) above, obtain the advancing speed of the welding tool and set it as a reference advancing speed, and obtain the rotational speed of the welding tool at that time and set it as the reference rotational speed. step,
(d) When performing friction stir welding of the members to be welded, the reference advancing speed is set as a target value of the advancing speed for each of the divided sections, and/or the reference rotational speed is set to be the same as the rotational speed. Step to set as target value.

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