JP6412627B1 - Friction stir welding apparatus, friction stir welding method, friction stir welding apparatus with database, friction stir welding method using database, control apparatus for friction stir welding apparatus - Google Patents

Abstract

【Task】
Friction stir welding that enables high-quality (high precision) joining by controlling the temperature difference between AS (advancing side) and RS (retreating side) during friction stir welding according to the state of joining members and joining conditions An apparatus and a friction stir welding method are provided.
[Solution]
A joining tool configured by a shoulder part and a probe part, inserted into a member to be joined and rotated, an apparatus main body for holding the joining tool, a control device for controlling the operation of the joining tool, and an AS of the member to be joined A friction stir welding apparatus comprising: a first temperature sensor that measures the temperature of (advancing side); and a second temperature sensor that measures the temperature of the RS (retreating side) of the member to be joined, Based on the bonding temperature measured by the first temperature sensor and the second temperature sensor, at least one of a rotation speed and a traveling speed of the bonding tool is controlled.
[Selection] Figure 1

Description

  The present invention relates to a friction stir welding apparatus and a friction stir welding method for joining members to be joined by friction stir welding, and in particular, applied to joining of members to be joined that require high quality (high accuracy) joining. It relates to effective technology.

  Friction Stir Welding (FSW) that softens the material to be welded by friction heat generated by rotating a cylindrical joining tool and stirs the part to join the materials to be joined. Since no material is used, fatigue strength is high, and since the material does not melt, joining with less welding deformation (strain) is possible, and applications in a wide range of fields such as aircraft and automobile bodies are expected.

  As a background art in this technical field, for example, there is a technique such as Patent Document 1. Patent Document 1 discloses a “friction stir welding apparatus in which a plurality of temperature sensors are provided at internal positions of protrusions having different depths from the surface of the member to be joined when the protrusions of the joining tool are press-fitted into the member to be joined”. Is disclosed. (See FIG. 4 of Patent Document 1)

Japanese Patent No. 5883978

  When the members to be joined are friction stir welded using the FSW device, generally, the optimum joining conditions (rotation speed and joining speed of the joining tool) for the members to be joined are determined before the joining operation is started. Set to. In the conventional FSW devices, the set joining conditions are maintained from the start of joining to the end of joining, and the joining is controlled.

  However, in the conventional bonding in which the bonding conditions are initially set and the bonding conditions are maintained until the bonding is completed, the left and right regions of the bonding line, that is, an advanced side (hereinafter also referred to as an AS) and a retrieving side (hereinafter referred to as an “advancing side”). , RS: also called retreating side), it has been found that high-quality joining results may not be obtained depending on conditions such as material, shape, and thickness of the members to be joined.

  The inventors of the present application have studied to further improve the above temperature management method in order to perform higher-quality friction stir welding. As a result, in order to obtain high-quality bonding, temperature measurement is not performed by using a non-contact temperature measurement device, rather than measuring the bonding temperature by placing a temperature measurement device inside the welding tool or inside the shoulder. Therefore, it is effective to measure the temperature at two points instead of the temperature at one point and maintain (control) the temperature difference between the two points within a predetermined range. I found out.

  In the above-mentioned Patent Document 1, a temperature measuring instrument is arranged inside the welding tool or inside the shoulder, the temperature in the vicinity of the joint is acquired from the inside of the member to be joined, and the temperature is managed. Problems such as inability to measure or inability to perform second temperature control occur.

  The inventors of the present application have confirmed through experiments that if a temperature measuring device is disposed in the shoulder and in the vicinity of the outer periphery of the shoulder, the temperature is not accurately measured due to the influence of outside air.

Further, if a temperature measuring device is disposed inside the welding tool and the shoulder, the temperature measuring device rotates simultaneously with the rotation of the welding tool and the shoulder portion, and the temperature difference between AS and RS cannot be detected. (When the joining tool (and the shoulder part) rotates, the AS joining temperature becomes higher than the RS joining temperature.)
Furthermore, by maintaining the difference in temperature between these two junctions within a predetermined range, it is possible to maintain high junction quality. However, if the temperature measuring instrument itself rotates, the difference in temperature between AS and RS will be reduced. It cannot be detected, and high bonding quality cannot be maintained.

  Therefore, the object of the present invention is to control the temperature difference between AS (advancing side) and RS (retreating side) at the time of friction stir welding according to the state and joining conditions of the members to be joined, and to achieve high quality (high accuracy). An object of the present invention is to provide a friction stir welding apparatus and a friction stir welding method capable of performing smooth joining.

In order to solve the above-described problems, the present invention includes a joining tool that includes a shoulder portion and a probe portion, and is inserted into a member to be joined and rotates, an apparatus main body that holds the joining tool, and an operation of the joining tool. A control device for controlling, a first temperature sensor for measuring an AS (advancing side) temperature of the bonded member, and a second temperature sensor for measuring the temperature of an RS (retreating side) of the bonded member And the first temperature sensor and the second temperature sensor are arranged on the outer periphery of the shoulder portion at positions symmetrical with respect to a joining line when the joining tool advances. disposed in the apparatus body so as to measure the junction temperature in the vicinity, and a total of the junction temperature by avoiding the burrs produced on the workpieces surface when friction stir welding the workpieces It is arranged to, based on the first temperature sensor and the junction temperature measured by the second temperature sensor, and controlling at least one of the rotational speed and the moving speed of the welding tool .

  Further, the present invention is a friction stir welding method for joining members to be joined by friction stir welding, wherein (a) determining a target temperature during friction stir welding based on the state of the members to be joined; ) Measuring the AS (advanced side) joining temperature of the member to be joined at the time of friction stir welding, which is a reference temperature; and (c) RS of the member to be joined at the time of friction stirring joining, which is a comparative temperature. (Retreating side) measuring the bonding temperature, and (d) the rotation speed and the traveling speed of the bonding tool so as to keep the deviation between the target temperature and the reference temperature within a first predetermined range. Controlling at least one of: (e) the rotational speed and the traveling speed of the welding tool so as to maintain a deviation between the reference temperature and the comparative temperature within a second predetermined range; Even without and having the steps of: controlling either.

  In addition, the present invention is a friction stir welding apparatus having a database for determining a joining condition, which includes a shoulder part and a probe part, and is inserted into a member to be joined and rotates, and the joining tool is held. An apparatus main body, a control device for controlling the operation of the joining tool, a first temperature sensor for measuring an AS (advancing side) temperature of the joined member, and an RS (retreating side) of the joined member ) Is measured in advance based on the state of the second member to be joined, the joining member state, the AS (advancing side) joining temperature, the RS (retreating side) joining temperature, and the joining tool joining condition. A junction temperature measured by the first temperature sensor and the second temperature sensor, and the database. While, and controlling at least one of the rotational speed and the moving speed of the welding tool.

  Further, the present invention is a friction stir welding method using a database for determining a joining condition, wherein (a) a state of a member to be joined, an AS (advancing side) joining temperature, and an RS (retreating side) joining temperature. A step of reading a database set in advance based on the joining conditions of the joining tool, (b) a step of measuring an AS (advancing side) joining temperature of the joined member, and (c) an RS of the joined member (Retreating side) junction temperature measuring step, (d) AS (advancing side) junction temperature measured in step (b) and RS (retreating side) measured in step (c) By collating the welding temperature with the database, the rotational speed and traveling speed of the welding tool can be reduced. And controlling either.

  Further, the present invention is a control device for a friction stir welding apparatus including a database for determining a welding condition, the control device being connected to the friction stir welding apparatus via a centralized management system, and the friction stir welding The apparatus comprises a shoulder part and a probe part, and is inserted into a member to be joined and rotates, a device main body for holding the joining tool, a drive control unit for controlling the operation of the joining tool, and the article to be joined. A first temperature sensor that measures an AS (advancing side) temperature of the joining member; and a second temperature sensor that measures an RS (retreating side) temperature of the joined member, and the control device Is based on the condition of the member to be joined, the AS (advancing side) joining temperature, the RS (retreating side) joining temperature, and the joining conditions of the joining tool. A database that is set, and at least one of the rotational speed and the traveling speed of the welding tool is compared with the bonding temperature measured by the first temperature sensor and the second temperature sensor and the database. It is characterized by controlling.

  According to the present invention, the temperature difference between the AS (advancing side) and the RS (retreating side) at the time of friction stir welding is controlled according to the state of the members to be joined and the joining conditions, and high quality (high accuracy) joining is achieved. The friction stir welding apparatus and the friction stir welding method can be realized.

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

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the whole outline | summary of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the temperature measurement mechanism of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows control (action | operation) of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows the friction stir welding method which concerns on one Embodiment of this invention. It is a figure which shows the database (control table) of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the temperature measurement mechanism of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the temperature measurement mechanism of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the temperature measurement mechanism of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the temperature measurement mechanism of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the temperature measurement mechanism of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the whole control system of the friction stir welding apparatus which concerns on one Embodiment of this invention. It is a figure which shows the subject in the conventional friction stir welding.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and detailed description of the overlapping portions is omitted.

  The friction stir welding apparatus and the friction stir welding method of Example 1 will be described with reference to FIGS. 1 to 4 and FIG. FIG. 1 shows an overall outline of a friction stir welding apparatus 1 of this embodiment. FIG. 2 is a view taken in the direction of the arrow A-A ′ in FIG. 1 and shows the temperature measurement mechanism of this embodiment. FIG. 3 is a graph conceptually showing temperature control (action) at the time of friction stir welding according to this embodiment. FIG. 4 is a flowchart showing a typical friction stir welding method according to this embodiment. FIG. 10 is a view showing a state of conventional friction stir welding for explaining the above-described problem of the present invention.

  First, with reference to FIG. 10, the problems of the above-described conventional friction stir welding will be described in detail. FIG. 10 is a diagram schematically showing a state of friction stir welding by a conventional friction stir welding apparatus, and shows a state where the friction stir welding apparatus and the member to be joined are viewed from the upper surface side.

  As shown in FIG. 10, in the friction stir welding apparatus, a joining pin (probe part) 8 at the tip of a joining head (holder part) 5 held by the apparatus main body 2 via a holder part holding part 4 has a member 9a to be joined. 9b is inserted into the bonding interface (bonding line) and rotated at a high speed to generate frictional heat. The frictional heat softens the material to be bonded and agitates the part to be bonded (9a, 9b) is joined.

  The joining pin (probe portion) 8 joins the members to be joined (9a, 9b) while proceeding in the X direction (the direction of the white arrow in FIG. 10) along the joining line (joining interface). Further, the joining pin (probe part) 8 rotates at high speed clockwise (in the direction of the arrow in the curve in FIG. 10) together with the joining head (holder part) 5.

  For this reason, in the vicinity of the bonding head (holder part) 5 on the left side of the bonding line (bonding interface), the traveling direction and the rotational direction of the bonding head (holder part) 5 coincide, and the relative traveling speed or relative rotation. Speed increases (rises). On the other hand, in the vicinity of the joining head (holder part) 5 on the right side of the joining line (joining interface), the traveling direction and the rotating direction of the joining head (holder part) 5 are opposite to each other, and the relative traveling speed or relative The rotational speed decreases.

  For joining members to be joined by friction stir welding, joining members (9a, 9b) are butted against each other, and a joining pin (probe portion) 8 is inserted into the abutting portion to join the friction stir welding ( So-called “butt joint”; in this case, the butted surface becomes the joint interface) and the end portions of the members to be joined (9a, 9b) are overlapped, and the joining pin (probe portion) 8 is inserted into the overlapped portion Then, there is a joining method in which friction stir welding is performed (so-called “lap joining”; in this case, a joining interface is formed in the overlapped region). In each embodiment of the present specification, the joining interface and the joining tool are used. A description will be given using the former “butt joint” example in which the center (joint pin 8) is arranged and joined so as to be on the same line.

  However, the present invention is not limited to either “butt joining” or “lap joining”, and it goes without saying that the present invention can be applied to friction stir welding in general including both.

  Here, in the advancing direction and the rotating direction of the bonding head (holder part) 5 shown in FIG. 10, the region on the left side of the bonding line (bonding interface) is an advanced side (AS), and the bonding line (bonding) A region on the right side of the interface) is a retreating side (RS).

  Further, since AS and RS are determined by the advancing direction and the rotating direction of the joining head (holder part) 5, for example, in FIG. 10, the joining head (holder part) 5 rotates counterclockwise (the curve of FIG. 10). When rotating in the direction opposite to the arrow direction), the region on the left side of the bonding line (bonding interface) is RS, and the region on the right side of the bonding line (bonding interface) is AS.

  As shown in FIG. 10, when the joining line (joining interface) coincides with the locus of the center point of the joining tool part (joining head), that is, the locus of the probe part (joining pin) 8, the joining line (joining interface). Alternatively, AS and RS can be defined based on the trajectory of the center point of the welding tool part (joining head). However, for example, when different materials are to be joined, depending on the material, it may be more expensive to perform the friction stir welding by inserting the probe portion (joining pin) 8 at a position away from the joining interface (butting surface between the different materials). A quality bond may be obtained. In such a case, since the trajectory of the center point of the joining interface (butting surface between different materials) and the joining tool part (joining head) does not coincide with each other, the material of the member to be joined is also considered and the boundary between AS and RS ( ).

As described above, in the traveling direction and the rotational direction of the joining head (holder part) 5 shown in FIG. 10, the traveling direction and the rotational direction of the joining head (holder part) 5 in the AS coincide with each other. The relative rotational speed increases (rises). On the other hand, in RS, the traveling direction and the rotational direction of the bonding head (holder part) 5 are opposite to each other, and the relative traveling speed or the relative rotational speed decreases. As a result, as shown in FIG. 10, the AS joining temperature T _AS at the time of friction stir welding becomes higher than the _RS joining temperature T _RS . (T _AS > T _RS ) This temperature difference is about 30 ° C. to 50 ° C. when the member to be joined is, for example, aluminum (AL).

  In friction stir welding, the joining temperature at the time of friction stir welding is an important factor in obtaining high joining reliability (joining quality). As described above, the left and right regions of the joining line (joining interface), that is, AS, Depending on the temperature difference of the RS, depending on conditions such as the material and shape / thickness of the members to be joined, a high-quality joining result may not be obtained.

  Next, the friction stir welding apparatus of this embodiment and its control method will be described with reference to FIGS. As shown in FIG. 1, the friction stir welding apparatus 1 according to the present embodiment has, as main components, a holder part (joining head) that is connected to the apparatus main body 2 via the apparatus main body 2 and the vertical movement drive mechanism unit 3. 4, a holder part (joining head) 5 connected (held) to the holder part (joining head) holding part 4, and a joining tool part 6 held by the holder part (joining head) 5. As illustrated in FIG. 1, for example, a ball screw or the like is used for the vertical movement drive mechanism unit 3. The joining tool part 6 includes a shoulder 7 and a probe part (joining pin) 8, and the probe part (joining pin) 8 is held by the holder part (joining head) 5 through the shoulder 7.

  This probe portion (joint pin) 8 is inserted into the butted portion of the member 9 (9a, 9b) to be joined, and rotates at a high speed so that the probe portion (joint pin) 8 and the member 9 (9a, 9b) are joined. Friction heat is generated, and the frictional heat causes plastic flow in the members 9 (9a, 9b) to be agitated, thereby stirring the joint. When the probe portion (joining pin) 8 moves, the stirring portion (joining portion) is cooled and the members to be joined are joined together.

  1 shows a configuration in which the holder unit 5 and the welding tool unit 6 are connected (held) to the apparatus main body 2 via the holder unit holding unit 4 and the vertical movement drive mechanism unit 3, but the present invention is not limited thereto. For example, a configuration that is connected (held) to the apparatus main body 2 only through the vertical movement drive mechanism unit 3 or a structure that is connected (held) to the apparatus main body 2 via other movable means, A configuration in which the holder unit 5 and the joining tool unit 6 are directly connected (held) to the apparatus main body 2, or a configuration in which a C-shaped frame is further provided between the holder unit 5 and the apparatus main body 2 in the configuration of FIG. The configuration connected (held) to the apparatus main body 2 having a robot arm is also included in the scope of the present embodiment.

  The apparatus main body 2 is provided with a temperature measurement mechanism including a temperature sensor gripping mechanism 10 and non-contact temperature sensors 11 (11a, 11b). In this temperature measurement mechanism, a non-contact temperature sensor 11 (11a, 11b) is disposed in the apparatus main body 2 via a temperature sensor gripping mechanism 10, and the temperature of the member 9 (9a, 9b) to be joined is contactless. measure.

  For the temperature sensor 11 (11a, 11b), for example, a non-contact thermometer using far infrared rays or a non-contact thermometer using laser is used. Or you may use the thermography etc. which arrange | position an image pick-up element and perform image analysis of the infrared rays radiated | emitted from a to-be-joined member.

  The apparatus main body 2 is provided with a control unit (control apparatus) 12 that controls the operation of the friction stir welding apparatus 1. The control unit (control device) 12 is a welding condition signal for determining a welding condition by the welding tool unit 6, and a holding position in the height direction (Z direction) of the welding tool unit 6 by the vertical movement drive mechanism unit 3 (of the bonding pin 8. A storage unit (not shown) is provided for storing a bonding parameter (FSW bonding condition) such as a holding position determination signal for determining an insertion amount).

  FIG. 2 shows a state of temperature measurement of the member 9 (9a, 9b) to be joined by the temperature measurement mechanism of the present embodiment. In FIG. 2, it is assumed that the holder unit 5 (and the shoulder unit 7 and the probe unit 8) rotate clockwise and move to the back side of the paper surface (that is, the X direction). Therefore, the insertion position of the probe 8 to the member 9 (9a, 9b), that is, the left side of the bonding line (bonding interface) is AS, and the right side is RS.

  As shown in FIG. 2, at the time of friction stir welding, burrs 13 are generated on the surface of the member 9 (9a, 9b). Since the burr 13 during the friction stir welding is at a high temperature, the bonding temperature of the member 9 (9a, 9b) cannot be accurately measured. Therefore, as shown in FIG. 2, it is necessary to measure the bonding temperature of the member 9 (9a, 9b) while avoiding the burr 13. In FIG. 2, the AS junction temperature is measured by the temperature sensor 11a (first temperature sensor), and the RS junction temperature is measured by the temperature sensor 11b (second temperature sensor). The temperature sensor 11a (first temperature sensor) and the temperature sensor 11b (second temperature sensor) are provided so that the arrangement position (the position of the holder portion 5 in the rotational radial direction) with respect to the apparatus body 2 is variable. Therefore, it is possible to measure the joining temperature of the member 9 (9a, 9b) while avoiding the burr 13 generated during the friction stir welding.

  In FIG. 2, the temperature sensor 11 a and the temperature sensor 11 b are symmetrically positioned with respect to the joining line (joining interface) when the joining tool (holder part 5, shoulder part 7, probe part 8) travels. It is disposed in the apparatus main body 2 via the gripping mechanism 10 so as to measure the bonding temperature in the vicinity of the outer periphery of the shoulder portion 7. By arranging in this way, it is possible to measure the bonding temperature at the same distance (equivalent position) from the bonding line (bonding interface) in each of AS and RS, and to control the bonding temperature of AS and RS described later. Can be done accurately.

  When the temperature sensor 11 (11a, 11b) is configured to rotate together with the welding tool as in Patent Document 1, the temperature difference between AS and RS cannot be measured. Therefore, in this embodiment, the gripping mechanism is provided so that the temperature sensor 11 (11a, 11b) is held at the same position independently of the rotation of the joining tool (holder part 5, shoulder part 7, probe part 8). 10 is disposed in the apparatus main body 2.

  The temperature sensor 11 (11a, 11b) may be provided so as not to rotate together with the rotation of the welding tool. For example, the movement of the welding tool (movement toward the back side (X direction) in FIG. 2). It is also possible to arrange it on another moving means provided independently of the welding tool so that it can move in synchronization with the welding tool.

  Further, the adjustment of the arrangement positions of the temperature sensor 11a and the temperature sensor 11b with respect to the apparatus main body 2 (the position of the holder portion 5 in the rotational radial direction) may be performed manually, and the temperature sensor driving means is provided in the gripping mechanism 10. For example, it may be automatically adjustable according to the state (material, plate thickness, plate width, shape, etc.) of the members to be joined and the joining conditions of the FSW by a database (control table) described later.

  Subsequently, the bonding temperature control by the friction stir welding apparatus of the present embodiment will be described with reference to FIG. The vertical axis in FIG. 3 indicates the bonding temperature (° C.), and the horizontal axis indicates the elapsed time (t). FIG. 3 shows the transition of the AS junction temperature (AS temperature) measured by the temperature sensor 11a (first temperature sensor) and the transition of the RS junction temperature (RS temperature) measured by the temperature sensor 11b (second temperature sensor). Respectively.

As shown in FIG. 3, when the probe portion (joining pin) 8 is inserted into the joined member 9 (9a, 9b), the joining temperature of the joined member 9 (9a, 9b) starts to rise, and the joining start point ( During the friction stir welding from the time t _s ) to the welding end point (t _e ), both the AS joining temperature T _AS and the RS joining temperature T _RS are maintained within a predetermined range. After the end of bonding, both the bonding temperature T _AS and the bonding temperature T _RS are lowered. Note that, as described above, the AS joining temperature T _AS at the time of friction stir welding is higher than the _RS joining temperature T _RS . (T _AS > T _RS )
Here, the AS joining temperature measured by the temperature sensor 11a (first temperature sensor) is used as a reference temperature, and this is determined by the reference temperature and the state of the member to be joined (material, plate thickness, plate width, shape, etc.). The rotational speed and traveling speed (X of the welding tool (holder part 5, shoulder part 7, probe part 8)) so as to keep the deviation from the target temperature within a predetermined range ΔT _AS (within the first predetermined range). Control the direction of travel in the direction).

Note that the rotational speed and the traveling speed of the welding tool are both important factors in determining the welding temperature. Therefore, by controlling at least one of the rotational speed and the traveling speed of the welding tool, The deviation between the temperature and the target temperature can be maintained within the predetermined range ΔT _AS (within the first predetermined range). (This junction temperature control is referred to as “first temperature control mode”.)
Subsequently, the junction temperature measured by the temperature sensor 11b (second temperature sensor) is set as a comparison temperature, and the deviation between the reference temperature measured by the temperature sensor 11a (first temperature sensor) and the comparison temperature is set within a predetermined range ΔT. The rotational speed and traveling speed (traveling speed in the X direction) of the joining tool (holder part 5, shoulder part 7, probe part 8) are controlled so as to be held in _RS (within the second predetermined range).

As in the above “first temperature control mode”, the deviation between the reference temperature and the comparison temperature is controlled within a predetermined range ΔT by controlling at least one of the rotational speed and the traveling speed of the welding tool. It can be held in the _RS (within the second predetermined range). (This junction temperature control is referred to as a “second temperature control mode”.)
By these “first temperature control mode” and “second temperature control mode”, the joining temperature of the member 9 (9a, 9b) to be joined by the joining tool (holder part 5, shoulder part 7, probe part 8) is set. It is held within a predetermined range ΔT.

  The “first temperature control mode” and the “second temperature control mode” are the AS junction temperature measured by the temperature sensor 11a (first temperature sensor) and the temperature sensor 11b (second temperature sensor). Based on the measured joining temperature and the target temperature set in advance according to the state of the member 9 (9a, 9b) (material, plate thickness, plate width, shape, etc.) Apparatus) 12 performs an arithmetic process and is determined.

  In the above description, the junction temperature control in which the “second temperature control mode” is executed following the execution of the “first temperature control mode” has been described. However, the “first temperature control mode” and the “second temperature control mode” are described. Temperature control mode "is performed at the same time (ie, the" first temperature control mode "is performed (selected) and held while the" second temperature control mode "is performed (selected)) Control), more accurate bonding temperature control becomes possible.

  Next, a typical friction stir welding method based on the bonding temperature control described above will be described with reference to FIG.

First, in accordance with a command from the control unit (control device), the welding tool (probe unit 8) is inserted into a predetermined position of the bonded portion of the bonded member 9 (the butted portion between the bonded members 9a and 9b). (Step S1)
Next, using the temperature sensor 11a (first temperature sensor) and the temperature sensor 1b (second temperature sensor), the AS joining temperature and the RS joining temperature of the member 9 to be joined are measured. (Step S2)
Then, based on the AS junction temperature and the RS junction temperature acquired in step S2, the control unit (control device) 12 calculates ΔT that is a threshold value (target control value) for the junction temperature control. (Step S3)
Subsequently, based on the threshold value (target control value) ΔT calculated in step S3, the rotational speed and traveling speed (traveling speed in the X direction) of the welding tool (probe unit 8) are controlled, and Friction stir welding is performed on the joined portions (butting portions of the joined members 9a and 9b). (Step S4)
Finally, when the moving amount (or elapsed time) of the joining tool (probe part 8) reaches a predetermined value (position / time), the joining tool (probe part 8) is removed from the joined part of the member 9 to be joined. Pull out to finish the friction stir welding process. (Step S5)
As described above, according to the friction stir welding apparatus and the friction stir welding method of the present embodiment, AS (advancing side) joining of the members to be joined using a plurality of (at least two) non-contact temperature sensors. The temperature and the RS (retreating side) junction temperature are measured, and a threshold value (target control value) ΔT for the temperature difference between the AS junction temperature and the RS junction temperature is determined based on the measured data. (Target control value) FSW joining conditions (rotation speed and traveling speed of the joining tool) are controlled so as to be within ΔT. Thereby, high quality (high accuracy) friction stir welding can be realized.

  In addition, even when joining without advancing the joining tool as in spot joining, the contact-type temperature measuring device as in Patent Document 1 needs to be replaced when the member to be joined is replaced with the next one. Thus, complicated work occurs, and the number of work steps increases. However, by using a non-contact temperature sensor as in this embodiment, work efficiency can be dramatically improved.

  With reference to FIG. 5, the friction stir welding apparatus and the friction stir welding method of Example 2 will be described. FIG. 5 shows an example of a database (control table) used for the junction temperature control of this embodiment. Note that the database (control table) shown in FIG. 5 is an example for easy understanding of the description, and the conditions (states) of the members to be joined and the parameters of the FSW joining conditions constituting the database (control table) are limited to these. It is not something.

  In the first embodiment, the AS bonding temperature (reference temperature) measured by the temperature sensor 11a (first temperature sensor), the state of the member 9 (9a, 9b) (material, plate thickness, plate width, shape, etc.) ) Based on the target temperature set in advance according to the temperature and the junction temperature (comparative temperature) measured by the temperature sensor 11b (second temperature sensor), the control unit (control device) 12 performs arithmetic processing, and the threshold value (target control) Value) ΔT is determined.

  On the other hand, in the present embodiment, based on past accumulated data of friction stir welding and the condition (condition) of the member to be welded calculated by simulation, the correlation between the FSW welding condition and the threshold value (target control value) ΔT. A database (control table) as shown in FIG. 5 is created (registered) in advance, and when the members to be joined 9a and 9b are friction stir welded, information in this database (control table) is transferred to a control unit (control device). 12 is read.

  As information (parameters) in the database (control table), for example, as shown in FIG. 5, the material of the member 9a to be joined (material A), the material of the member 9b to be joined (material B), Thickness, width, shape, etc. are mentioned. Further, as the FSW bonding conditions, the number of rotations of the bonding tool (probe unit 8), the rotation speed or traveling speed of the bonding tool (probe unit 8), the AS bonding temperature, and the like can be given.

  The control unit (control device) 12 stores the AS junction temperature measured by the temperature sensor 11a (first temperature sensor) and the junction temperature measured by the temperature sensor 11b (second temperature sensor) in this database (control table). The FSW joining conditions (rotation speed and progress speed of the joining tool) are controlled so that the joining temperature is within the threshold value (target control value) ΔT of the database (control table) by collating with the information. Thereby, like Example 1, high quality (high precision) friction stir welding can be realized.

  In Example 1, when the members to be joined are friction stir welded, it is necessary to set the target temperature according to the state of the members to be joined (material, plate thickness, plate width, shape, etc.). In the example, since the information of the database (control table) created (registered) in advance is read, the workability (working efficiency) is improved. For example, even unskilled workers can reproduce high quality (high precision) friction. Stir welding can be performed.

  If the state of the member to be joined is different (when the member to be joined is changed), the database (control table) according to the state (material, plate thickness, plate width, shape, etc.) of the member 9 (9a, 9b) to be joined. May be added or updated.

  A friction stir welding apparatus and a friction stir welding method of Example 3 will be described with reference to FIGS. 6 is a view taken in the direction of the arrow B-B ′ in FIG. 1 and is shown for comparison. FIG. 7A is a diagram showing a temperature measurement mechanism of the present embodiment, and similarly to FIG. 6, shows a state at the time of friction stir welding when the friction stir welding apparatus 1 of FIG. 1 is viewed from the B-B ′ direction. 7B and 7C are modifications of FIG. 7A. FIG. 8 shows still another modification of the temperature measuring mechanism, and corresponds to a view taken in the direction of the arrow A-A ′ in FIG. 2.

  As shown in FIG. 6, in Example 1, the temperature sensor 11a and the temperature sensor 11b are symmetrical with respect to the joining line (joining interface) when the joining tool (holder part 5, probe part 8) advances. It is arranged in the apparatus main body 2 via the gripping mechanism 10 so as to measure the bonding temperature in the vicinity of the outer periphery of the shoulder portion at the position. As shown in FIG. 6, by disposing the temperature sensors 11a and 11b at positions that are line-symmetric with each other on a straight line that intersects perpendicularly with the bonding line (bonding interface), the distance from the center point (bonding line) of the bonding is equal. The bonding temperatures can be compared.

  In contrast, in the temperature measurement mechanism of the present embodiment, as shown in FIG. 7A, the temperature sensor 11a and the temperature sensor 11b are rotated by a welding tool (holder part 5, probe part 8; reference numerals are omitted in FIG. 7A). It arrange | positions in the apparatus main body 2 via the holding | grip mechanism 10 so that the joining temperature of the shoulder part outer periphery vicinity of the position mutually symmetrical with respect to the center may be measured. As in the present embodiment (FIG. 7A), by arranging the temperature sensors 11a and 11b at positions that are point-symmetric with respect to the rotation center of the welding tool, for example, the bonded member 9a and the bonded member 9b are When different materials such as different materials are friction stir welded, the optimum temperature measurement position used for welding temperature control is also different from the positions that are symmetrical with respect to the joining line as shown in FIG. Can do.

  In addition, as shown in FIG. 6, the temperature sensors 11a and 11b are arranged at positions that are symmetrical with each other on a straight line that passes through the rotation center of the welding tool (holder unit 5 and probe unit 8) and perpendicularly intersects the bonding line (bonding interface). In contrast, as shown in FIG. 7B, the temperature sensor 11a does not pass through the center of rotation of the joining tool (holder part 5, probe part 8) and is in line symmetry with respect to the joining line (joining interface). 11b may be provided.

  Further, as shown in FIG. 7C, temperature sensors 11 a and 11 b may be provided to measure each AS / RS junction temperature on the inner side (joint line side) than the burr (weld bead) 13.

  Furthermore, as shown in FIG. 8, the temperature sensors 11a and 11b may be arranged with angles θ and θ ′ in the Y direction, respectively. For example, in the case where the burr 13 is generated at a position separated from the outer periphery of the shoulder portion 7, and the optimum temperature measurement position used for the bonding temperature control is in the vicinity of the bonding tool (shoulder portion 7, probe portion 8). In some cases, by adjusting the angles θ and θ ′ of the temperature sensors 11a and 11b, it is possible to avoid the burr 13 and measure the junction temperature at the optimum position.

  7A, FIG. 7B, FIG. 7C, and FIG. 8 may be configured to manually adjust the angles θ and θ ′ of the temperature sensor 11a and the temperature sensor 11b. The temperature sensor angle adjustment means is provided, and the above-mentioned database (control table) can be automatically adjusted according to the state of the member to be joined (material, plate thickness, plate width, shape, etc.) and FSW joining conditions. Good.

  With reference to FIG. 9, the control system of the friction stir welding apparatus of Example 4 and the control apparatus of the friction stir welding apparatus used therefor will be described. FIG. 9 shows an overall outline of the control system of the friction stir welding apparatus of the present embodiment. In the friction stir welding apparatus 1 of this embodiment, only the drive unit 14 that mainly drives the friction stir welding apparatus 1 is installed in the apparatus main body 2 in place of the control unit (control apparatus) 12 of the first embodiment (FIG. 1). In the point which is done, it differs from the friction stir welding apparatus of Example 1. As shown in FIG. 9, the drive unit 14 is connected to a centralized management system 15 such as a factory where the friction stir welding apparatus 1 is installed via a network. The central control system 15 is connected to a central control device 16 that is installed independently of the friction stir welding apparatus 1, and this central control device 16 is described in, for example, Embodiment 2 (FIG. 5). By providing such a database (control table), a control command (control signal) based on the database (control table) of the central control device 16 is sent to the drive unit 14 of the friction stir welding apparatus 1 via the centralized management system 15. This is transmitted and the joining temperature control at the time of friction stir welding by the friction stir welding apparatus 1 is performed.

  As in the present embodiment, the drive unit 14 is installed in the apparatus main body 2 of the friction stir welding apparatus 1, the control function is provided to the central control apparatus 16, and the friction stir welding apparatus 1 is connected via the network and the centralized management system 15. By controlling the drive unit 14, for example, it is possible to control the bonding temperature of a plurality of friction stir welding apparatuses connected to the network (centralized management system 15) with one central controller 16. it can.

  As a result, the initial cost for introducing the equipment can be suppressed, and a plurality of friction stir welding apparatuses are controlled by the same central control device 16, thereby reducing the difference in joining quality between the friction stir welding apparatuses. can do.

  In addition, during the friction stir welding, the joint temperature data measured by the temperature sensors 11a and 11b of the friction stir welding apparatus 1 is fed back to the central control device 16 via the network (centralized management system 15), and the database ( Control table information) may be added or updated.

  The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Friction stir welding apparatus, 2 ... Apparatus main body, 3 ... Vertical motion drive mechanism part (ball screw), 4 ... Holder part (joining head) holding part, 5 ... Holder part (joining head), 6 ... Joining tool part, DESCRIPTION OF SYMBOLS 7 ... Shoulder part, 8 ... Probe part (joining pin), 9, 9a, 9b ... Joined member, 10 ... (Temperature sensor) Grasping mechanism, 11, 11a, 11b ... (Non-contact) Temperature sensor, 12 ... Control part (Control device), 13 ... burr, 14 ... drive unit, 15 ... centralized management system, 16 ... central control device.

Claims (18)

A welding tool composed of a shoulder part and a probe part, inserted into a member to be joined and rotated,
An apparatus main body for holding the joining tool;
A control device for controlling the operation of the welding tool;
A first temperature sensor that measures the temperature of an AS (advancing side) of the member to be joined;
A friction stir welding apparatus comprising: a second temperature sensor for measuring a temperature of RS (retreating side) of the member to be joined,
The apparatus main body is configured to measure the bonding temperature in the vicinity of the outer periphery of the shoulder at a position that is symmetrical with respect to a bonding line when the bonding tool advances. And is arranged so as to measure the bonding temperature by avoiding burrs generated on the surface of the member to be bonded when the members to be bonded are subjected to friction stir welding.
A friction stir welding apparatus that controls at least one of a rotation speed and a traveling speed of the welding tool based on a bonding temperature measured by the first temperature sensor and the second temperature sensor. The friction stir welding apparatus according to claim 1,
The friction stir welding apparatus, wherein the first temperature sensor and the second temperature sensor are disposed in the apparatus main body and are held at the same position independently of rotation of the welding tool. The friction stir welding apparatus according to claim 1,
The friction stir welding apparatus according to claim 1, wherein the first temperature sensor and the second temperature sensor are arranged to be movable in synchronization with the movement of the welding tool. The friction stir welding apparatus according to any one of claims 1 to 3,
The first temperature sensor and the second temperature sensor are disposed in the apparatus main body so as to measure a bonding temperature in the vicinity of the outer periphery of the shoulder at a position that is symmetrical with respect to the rotation center of the bonding tool. A friction stir welding apparatus characterized by the above. The friction stir welding apparatus according to any one of claims 1 to 4 ,
The friction stir welding apparatus according to claim 1, wherein the first temperature sensor and the second temperature sensor are disposed such that positions relative to the apparatus main body can be adjusted via a gripping mechanism. The friction stir welding apparatus according to any one of claims 1 to 5 ,
The friction stir welding apparatus according to claim 1, wherein the first temperature sensor and the second temperature sensor are temperature sensors capable of measuring a bonding temperature without contact. The friction stir welding apparatus according to any one of claims 1 to 6 ,
The control device uses a joining temperature measured by the first temperature sensor as a reference temperature, and maintains a deviation between the reference temperature and a target temperature determined by the state of the joined member within a first predetermined range. Thus, the friction stir welding apparatus has a first temperature control mode for controlling at least one of a rotation speed and a traveling speed of the welding tool when the members to be welded are friction stir welded. The friction stir welding apparatus according to claim 7 ,
The control device further uses the bonding temperature measured by the second temperature sensor as a comparison temperature, and maintains the deviation between the reference temperature and the comparison temperature within a second predetermined range. A friction stir welding apparatus having a second temperature control mode for controlling at least one of a rotation speed and a traveling speed of the welding tool when the members are friction stir welded. The friction stir welding apparatus according to claim 8 ,
The said control apparatus selects the said 2nd temperature control mode, selecting and hold | maintaining the said 1st temperature control mode, The friction stir welding apparatus characterized by the above-mentioned. A friction stir welding method for joining members to be joined by friction stir welding,
(A) determining a target temperature at the time of friction stir welding based on the state of the members to be joined;
(B) measuring a joining temperature of AS (advancing side) of the member to be joined at the time of friction stir welding, which is a reference temperature;
(C) measuring a joining temperature of RS (retreating side) of the member to be joined at the time of friction stir welding, which is a comparative temperature;
(D) controlling at least one of the rotational speed and the traveling speed of the welding tool so as to maintain the deviation between the target temperature and the reference temperature within a first predetermined range;
(E) controlling at least one of the rotational speed and the traveling speed of the welding tool so as to maintain a deviation between the reference temperature and the comparison temperature within a second predetermined range;
A friction stir welding method characterized by comprising: The friction stir welding method according to claim 10 ,
Friction stir welding characterized in that the reference temperature and the comparison temperature measure a joining temperature in the vicinity of the outer periphery of the shoulder portion of the joining tool at a position that is symmetrical to the joining line when the joining tool advances Method. The friction stir welding method according to claim 10 or 11 ,
The reference temperature and the comparison temperature are measured by avoiding burrs generated on the surfaces of the members to be bonded when the members to be bonded are friction stir bonded to each other. The friction stir welding method according to any one of claims 10 to 12 ,
The friction stir welding method, wherein the reference temperature and the comparison temperature are measured without contact. A friction stir welding apparatus having a database for determining welding conditions,
A welding tool composed of a shoulder part and a probe part, inserted into a member to be joined and rotated,
An apparatus main body for holding the joining tool;
A control device for controlling the operation of the welding tool;
A first temperature sensor that measures the temperature of an AS (advancing side) of the member to be joined;
A second temperature sensor for measuring the temperature of the RS (retreating side) of the member to be joined;
A database preset based on a state of the member to be joined, a joining temperature of AS (advancing side), a joining temperature of RS (retreating side), and a joining condition of the joining tool;
It is characterized in that at least one of the rotational speed and the traveling speed of the welding tool is controlled while comparing the bonding temperature measured by the first temperature sensor and the second temperature sensor with the database. Friction stir welding device with database. A friction stir welding apparatus comprising the database according to claim 14 ,
The friction stir welding apparatus provided with a database, wherein the database is added or updated when the state of the members to be joined is different. A friction stir welding method using a database for determining welding conditions,
(A) a step of reading a database set in advance based on a state of a member to be joined, a joining temperature of AS (advancing side), a joining temperature of RS (retreating side), and joining conditions of a joining tool;
(B) measuring a bonding temperature of AS (advancing side) of the member to be bonded;
(C) measuring a bonding temperature of RS (retreating side) of the bonded members;
(D) By comparing the AS (advanced side) junction temperature measured in the step (b) and the RS (retreating side) junction temperature measured in the step (c) with the database, A friction stir welding method using a database, wherein at least one of a rotational speed and a traveling speed of a tool is controlled. A friction stir welding method using the database according to claim 16 ,
The friction stir welding method using a database, wherein the database is added or updated when the state of the members to be joined is different. A control device for a friction stir welding apparatus having a database for determining welding conditions,
The control device is connected to the friction stir welding device via a centralized management system,
The friction stir welding apparatus includes a shoulder part and a probe part, and a joining tool that is inserted into a member to be joined and rotates,
An apparatus main body for holding the joining tool;
A drive controller for controlling the operation of the welding tool;
A first temperature sensor that measures the temperature of an AS (advancing side) of the member to be joined;
A second temperature sensor that measures the temperature of the RS (retreating side) of the member to be joined,
The control device includes a database set in advance based on the state of the member to be bonded, the bonding temperature of AS (advancing side), the bonding temperature of RS (retreating side), and the bonding condition of the bonding tool,
It is characterized in that at least one of the rotational speed and the traveling speed of the welding tool is controlled while comparing the bonding temperature measured by the first temperature sensor and the second temperature sensor with the database. Control device for friction stir welding equipment.

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