JP4854205B2 - Friction stirrer, probe control method, control program, and joined body manufacturing method - Google Patents

Description

  The present invention relates to a friction stirrer and a method for controlling the probe thereof, and in particular, aligns the coordinate system of the friction stirrer with the coordinate system of a coordinate measuring device (hereinafter referred to as a measuring device) to accurately The present invention relates to a friction stirrer that can be controlled, a probe control method, a probe control program, and a joined body manufacturing method.

  In the manufacture of a structure, a plurality of components are often joined together by welding or the like. In recent years, objects to be joined (hereinafter also referred to as workpieces) are often manufactured using various machine tools (hereinafter referred to as processing devices) based on CAD data. And the joining target object which completed manufacture is removed from a processing apparatus, and it attaches to the mounting base of a joining apparatus, and joins.

  As for the joining method, a friction stir welding method (hereinafter referred to as FSW) has attracted attention as a solid phase joining method. The principle of FSW is that a cylindrical rod (hereinafter referred to as a probe) having a projection (hereinafter referred to as a pin) is rotated at the center of an end surface (pressing surface) of the tip as disclosed in Patent Document 1 below. However, the pins are inserted into the abutted portions of the metal materials to be joined and are advanced in the joining direction. The pressing surface around the pin at the end of the probe serves to prevent the member from being cut and discharged to the outside when the pin enters the member, and to provide frictional heat from the member surface. The rotation of the probe generates frictional heat with the material to be joined, rapidly heating the material at the contact point, lowering the mechanical strength of the material, and high-temperature plasticization layer on the metal around the pressing surface and pin Form. The plasticized metal member is crushed on the front side in the direction of travel of the pin, and moves to the rear side due to mechanical stirring, forging action based on the shape and rotation direction of the pin. As a result, as the rotating probe travels, the frictional heat heats the joint on the front side of the traveling direction of the probe, creating a softened state. As a result, the oxide film is destroyed, the crushed metal is agitated, recombined on the back side of the probe, and the metal is cooled to form a solid weld. Here, in order to ensure the soundness of the joint, it is desirable to incline the rotation axis of the probe by a predetermined angle (hereinafter referred to as a forward angle) with respect to the moving direction of the probe.

  The teaching of joint lines in the FSW method, for example, stores the position coordinates of a plurality of points while moving the probe pins along the joint lines by operating the robot's manual operation panel in the same manner as in an articulated welding robot. (See, for example, Patent Document 2 below).

Patent Document 3 below includes a mechanism for freely changing the rotation axis of the probe, detects the normal line of the joining member and the tangential direction of the joint line, and uses the detected normal direction and tangential direction of the probe. A friction stir welding apparatus capable of joining curved shaped objects by controlling the inclination direction of the rotating shaft is disclosed.
Japanese Patent No. 2712838 International Publication No. WO97 / 06473 Pamphlet JP 2002-301580 A

  However, when the workpiece is removed from the processing device and attached to the mounting table of the joining device in order to perform joining after the production of the workpiece by the processing device, the coordinate axis of the processing device matches the coordinate axis of the joining device. For this reason, it is difficult to use the CAD data of the workpiece as it is as the information on the joining line. Therefore, normally, in order to ensure the mounting accuracy, it is necessary to prepare a mounting jig for each workpiece and to accurately install the jig on the mounting table, which requires a very complicated operation. The same applies to the devices disclosed in Patent Documents 1 to 3 above.

Also, as disclosed in Patent Document 2, in the method taught by along the actual bonding line probe, the diameter of the probe of a friction stir junction device is relatively large, the pin is small (for example, a probe The diameter of the pin is about 12 mm, the diameter of the pin is about 4 mm, and the height thereof is about 3 mm. Therefore, it is not easy to place the pin along the joining line because of the pressing surface. Since the friction stir welding machine is operated with extremely strong operating force, the components are formed using tough materials, and the workpiece is made of a low-strength material such as aluminum or magnesium. When the friction stir welding apparatus comes into contact with the workpiece during teaching, there is a problem that the workpiece is damaged and the product yield is lowered.

  In addition, it is desirable that the rotation axis of the probe is accurately inclined with respect to the joining surface by a predetermined advance angle and maintained, but it is difficult to set an accurate angle by operating the joining device by visual observation.

  The present invention provides a friction stirrer that can accurately specify the three-dimensional shape of the joining line of a workpiece, a probe control method, a control program, and a joined body manufacturing method in order to solve the above-described problems. For the purpose.

  The object of the present invention is achieved by the following means.

That is, the friction stir welding apparatus (1) according to the present invention is a friction stir welding apparatus including a probe, a driving means for the probe, and a control means, and the control data for determining the posture of the probe is: Including first control data at a plurality of measurement points on a joint line of a joint object and second control data at an interpolated position on the joint line between two adjacent measurement points, the control means Calculating the first control data using position vectors, normal vectors, and predetermined advance angles of the plurality of measurement points, and using the position vectors and the normal vectors of the plurality of measurement points, An interpolation position vector, an interpolation tangent vector, and an interpolation normal vector corresponding to the joint line between two adjacent measurement points are calculated by interpolation, and the interpolation position vector and the interpolation tangent vector are calculated. The interpolation normal vector and using the forward angle, the second control data is calculated, and controls the driving means using said first control data and the second control data, said probe It is characterized by controlling the posture.

  In the friction stir welding apparatus (2) according to the present invention, in the friction stir welding apparatus (1), the position vector and the normal vector of the previous measurement point are the first coordinates of the friction stir welding apparatus. Data measured by measuring means having a second coordinate system different from the system, the control data is data in the second coordinate system, and the measuring means is coordinate data in the first coordinate system. Are measured, and the control means measures the position data of the four points obtained by the measurement means, and the position data of the four points obtained by the measurement means, and Using the known coordinate data of the four points, a coordinate conversion parameter from the second coordinate system to the first coordinate system is obtained, and the control means uses the coordinate conversion parameter to calculate the control data. in front It is characterized by converting the data in the first coordinate system.

  Further, the friction stir welding apparatus (3) according to the present invention uses all of the position vectors in the friction stir welding apparatus (1) or (2), wherein the interpolation position vector is a predetermined boundary condition. Calculated by spline interpolation, the tangent vector of the measurement point is obtained in the process of spline interpolation of the position vector, and the interpolated tangent vector is calculated by spline interpolation using all of the tangent vectors under a predetermined boundary condition. The normal vector is a vector perpendicular to a plane formed by two points on the joint line sandwiching the measurement point and one point outside the joint line in the vicinity of the measurement point, and the interpolation normal line The vector is calculated by spline interpolation using all of the normal vectors under a predetermined boundary condition.

  In the friction stir welding apparatus (4) according to the present invention, in any one of the friction stir welding apparatuses (1) to (3), the interpolation position vector indicating that the control data indicates a position of the tip of the probe. And data indicating a direction inclined by the advance angle from the interpolation normal vector in a plane formed by the interpolation tangent vector and the normal vector.

Further, the probe control method (1) of the friction stir welding apparatus according to the present invention is a method for controlling the probe of the friction stir welding apparatus including a probe, a drive means for the probe, and a control means, The control data for determining the posture of the probe includes first control data at a plurality of measurement points on the joint line of the object to be joined, and second at an interpolated position on the joint line between two adjacent measurement points. A first step of calculating the first control data using position vectors, normal vectors, and predetermined advance angles of the plurality of measurement points; and the control The means uses the position vector and the normal vector of the plurality of measurement points, and interpolates an interpolation position vector and an interpolation tangent vector corresponding to the joint line between two adjacent measurement points by interpolation. And a second step of calculating the second control data using the interpolation position vector, the interpolation tangent vector, the interpolation normal vector, and the advance angle. And a fourth step in which the control means controls the driving means by using the first control data and the second control data to control the posture of the probe. It is a feature.

  Further, the probe control method (2) of the friction stir welding apparatus according to the present invention is the above-described probe control method (1) of the friction stir welding apparatus, wherein the position vector and the normal vector of the previous measurement point are The data measured by the measuring means having a second coordinate system different from the first coordinate system of the friction stir welding apparatus, the control data is data in the second coordinate system, and the measuring means 4th step of measuring the position of each of 4 points where coordinate data in the first coordinate system is known and 3 or more points determined not to be aligned on the same straight line, and the control means, Using the position data of the four points obtained by the measuring means and the known coordinate data of the four points, a fifth step for obtaining a coordinate conversion parameter from the second coordinate system to the first coordinate system. And a sixth step in which the control means converts the control data into data in the first coordinate system using the coordinate transformation parameter, wherein the sixth step comprises the second step and It is performed during the third step.

  Further, the probe control method (3) of the friction stir welding apparatus according to the present invention is the above-described probe control method (1) or (2) of the friction stir welding apparatus, wherein the interpolation position vector has a predetermined boundary condition. And the tangent vector of the measurement point is obtained in the process of spline interpolation of the position vector, and the interpolated tangent vector is determined by the predetermined boundary condition. The normal vector is calculated by spline interpolation using all of the vectors, and the normal vector is perpendicular to a plane formed by two points on the joint line in the vicinity of the measurement point and one point outside the joint line. The interpolation normal vector is calculated by spline interpolation using all of the normal vectors under a predetermined boundary condition. There.

  Moreover, the control method (4) of the probe of the friction stir welding apparatus according to the present invention is the probe control method (1) to (3) of the friction stir welding apparatus, wherein the control data is the probe Data indicating a direction inclined by the advance angle from the interpolation normal vector in a plane formed by the interpolation tangent vector and the normal vector. It is a feature.

  A method for producing a joined body according to the present invention is a method for producing a joined body using a friction stir welding apparatus including a probe, a driving means for the probe, and a control means, and the friction stir welding described above. The probe is controlled by one of the probe control methods (1) to (4), and the friction stir welding is performed along the joining line.

Further, the control program for the probe of the friction stir welding apparatus according to the present invention is a control program for determining the posture of the probe in a friction stir welding apparatus including a probe, a driving means for the probe, and a control means. Including first control data at a plurality of measurement points on the joint line of the joint object, and second control data at an interpolated position on the joint line between two adjacent measurement points, the control means A function of calculating the first control data using a position vector, a normal vector, and a predetermined advancing angle of the plurality of measurement points, and the position vector and the normal vector of the plurality of measurement points. A function of calculating an interpolation position vector, an interpolation tangent vector, and an interpolation normal vector corresponding to the joint line between two adjacent measurement points by interpolation, and During position vector, the interpolation tangent vector, using said interpolation normal vector and the forward angle, a function of calculating the second control data, using the first control data and the second control data A function of controlling the driving means to control the posture of the probe is realized.

  Further, the control program for the probe of the friction stir welding apparatus can be recorded on a computer-readable recording medium.

According to the present invention, even without data on the shape of the bonding target (CAD data or shape measurement data), it is possible to realize a friction stir junction device capable of performing the bonding if they have kind.

Furthermore, for each shape of the bonding target, or to manufacture a special positioning jig, and the work it is not required to accurately attaching the friction stir junction device bonding target, thereby enabling efficient joining operation.

  In addition, it is not necessary to teach the joint line along the tip of the probe, and it is possible to prevent damage to the workpiece.

  In addition to controlling the tip of the probe along the joining line, the probe can be controlled to tilt at a predetermined advancing angle, so that a higher quality joint can be formed.

  Therefore, adjustment and operation of the friction stirrer, which has conventionally relied on a skilled worker, can be facilitated, and the joining operation can be automated.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing a schematic configuration of a friction stir welding apparatus (hereinafter referred to as an FSW apparatus) according to an embodiment of the present invention. As shown in FIG. 1, the FSW device is configured to rotate the probe 1 and the probe 1 around the axis at a high speed in one direction while maintaining the posture of the probe 1, that is, the inclination direction of the probe 1 and the pin at the tip. A drive unit 2 that changes the position, a control unit 3 that controls the drive unit 2 so that the pins of the probe 1 move along the joining line, and a mounting table 4 on which a target workpiece is mounted are provided. Here, the positions of the probe 1, the drive unit 2, and the mounting table 4 are specified with respect to each other in the same coordinate system. The control unit 3 includes a CPU, a memory, a recording unit (none of which are shown) and the like, as in a normal digital machine control device. FIG. 1 shows a workpiece mounted on the stage 4 and a measuring device 5 which is a device different from the FSW device for measuring the shape of the workpiece and the position of each part. The control unit 3 acquires the measured coordinate data from the measurement device 5 via an interface unit (not shown). Further, the coordinate system of the present FSW apparatus is indicated as XYZ, and the coordinate system of the measurement apparatus is indicated as UVW, and these coordinate systems do not necessarily match.

  FIG. 2 is a flowchart showing a bonding process using the FSW device according to the present embodiment. Here, unless otherwise specified, the processing performed by the control unit 3 is performed by an internal CPU, and the CPU appropriately reads necessary data from a recording unit inside the control unit 3 to the internal memory, and sets a predetermined area of the internal memory as a work area. The temporary result during processing and the final processing result are recorded in the recording unit as appropriate. In the initial state, it is assumed that no workpiece is mounted on the stage 4.

  First, the coordinate system of the FSW device and the coordinate system of the measuring device 5 are matched. That is, conversion parameters for these coordinate systems are obtained. Assuming that the coordinates of the same point are (x, y, z) in the coordinate system of the FSW device and (u, v, w) in the coordinate system of the measuring device, these relationships are the translation of the coordinate system. When the movement and the rotational movement are taken into consideration, it is expressed as Expression 1.

ここで、ａ〜ｉ、ｌ〜ｎは２つの座標系の並進移動及び回転移動で決まるパラメータであり、３行３列の行列Ｍ、及び列ベクトルＬで表す。

Here, a to i and l to n are parameters determined by translation and rotation of two coordinate systems, and are represented by a matrix M of 3 rows and 3 columns and a column vector L.

  Therefore, if these parameters M and L are determined, the coordinate data measured by the measuring device 5 can be converted into data usable by the FSW device. Therefore, in step S1, instead of the probe 1, a drill having a relatively small diameter is attached to the FSW apparatus, and a flat plate is attached to the stage 4 parallel to the XY plane in the coordinate system XYZ of the FSW apparatus. Here, it is assumed that the flat plate surface is installed so as to pass through the point A (0, 0, z).

  In step S2, the control unit 3 controls the drive unit 2, and three points A (0, 0, z), B (x, 0, z), C (0, y, z) in the coordinate system of the FSW device. Drill a hole into.

In step S3, the measurement device 5 measures the position coordinates of the origin O and the three holes opened in step S2. The control unit 3 acquires the measured position coordinates via a predetermined interface (for example, RS232C, GPIB, etc.). The coordinate data acquired by the control unit 3 is data in the coordinate system UVW of the measuring device 5. If they are (O _U , O _V , O _W ), (A _U , A _V , A _W ), (B _U , B _V , B _W ), (C _U , C _V , C _W ), these Is substituted into Equation 1 to obtain the following 12 equations.

That is, for point A,
0 = aA _U + bA _V + cA _W + l
0 = dA _U + eA _V + fA _W + m
z = gA _U + hA _V + iA _W + n
Regarding point B,
x = aB _U + bB _V + cB _W + l
0 = dB _U + eB _V + fB _W + m
z = gB _U + hB _V + iB _W + n
Regarding point C,
0 = aC _U + bC _V + cC _W + l
y = dC _U + eC _V + fC _W + m
z = gC _U + hC _V + iC _W + n
Regarding origin O
0 = aO _U + bO _V + cO _W + l
0 = dO _U + eO _V + fO _W + m
0 = gO _U + hO _V + iO _W + n
Holds.

Here, the origin O of the FSW device is known. For example, when Z = 0 is set as the surface of the mounting table 4, and X = Y = 0, the probe is returned by an origin return command from the control unit 3 to the drive unit 2. As described above, (O _U , O _V , O _W ) is coordinate data whose origin is measured by the measuring device 5, that is, coordinate data in the coordinate system UVW.

  In step S4, the control unit 3 determines these coordinate transformation parameters M and L by solving these simultaneous equations and records them in the recording unit. The four points to be measured can be selected at known coordinate positions different from the above as long as three or more points are not arranged on a straight line.

Next, it moves to the process which determines a joining line. In step S <b _> 5, the flat plate is removed, the workpieces to be joined are mounted on the mounting table 4, and the positions of _n measurement points P _{1 to} P _n on the joining line are measured by the measuring device 5. The measurement data is transmitted to the control unit 3, and the control unit 3 records the received measurement data. An example is shown in FIG. FIG. 3 is a perspective view showing two works A and B that form a semi-cylindrical shape when joined, and there are a plurality of measurement points P _{1 to} P _n on the joining line. Also it shows the tangent vector T ₂ at the measurement point P _2.

In step S6, the control unit 3 of the n measurement points P ₁ to P _n of the measurement of the position in step S5, it determines the joining line by interpolation between two adjacent points. Here, as an example, n point sequences are interpolated with a cubic spline curve.

The position vectors of the two points P _i and P _{i + 1} are P _i = (x _i , y _i , z _i ) and P _{i + 1} = (x _{i + 1} , y _{i + 1} , z _{i + 1} ). (In this specification, points and position vectors are given the same symbols), and tangent vectors at those points are expressed as T _i = (r _i , s _i , t _i ), T _{i + 1} = (r _{i + 1} , s _{i + 1} , t _{i + 1} ), a curve P (t) (vector) between two adjacent points P _i and P _{i + 1} is given by equation 2 using a cubic equation of parameter t. It is done.
P (t) = (2P _i −2P _{i + 1} + T _i + T _{i + 1} ) t ³ + (3P _{i + 1} −3P _i −2T _i −T _{i + 1} ) t ² + T _i t + P _i (Formula 2)
Here, t is 0 ≦ t ≦ 1, and Equation 2 is established for each component of the vector.

If this is applied to _n measurement points P _{1 to} P _n and a natural condition is set, that is, if the second derivative of the position vector P (t) is zero at the start and end points, Equation 3 becomes can get.

測定点Ｐ₁〜Ｐ_nの位置ベクトルＰ₁〜Ｐ_nは測定により得られているので、接線ベクトルＴ_k（ｋ＝１〜ｎ）について式３を解くことができる。その結果を式２に適用することによって、各区間の補間曲線、即ち補間された位置ベクトルＰ(ｔ)が得られ、これによって接合線全体を表す式が得られる。制御部３は、測定点Ｐ₁〜Ｐ_nの接線ベクトルＴ_k（ｋ＝１〜ｎ）、及び各区間の補間された位置ベクトルＰ(ｔ)を記録部に記録する。

Since the position vectors P _{1 to} P _n of the measurement points P _{1 to} P _n are obtained by measurement, Equation 3 can be solved for the tangent vector T _k (k = 1 to n). By applying the result to Expression 2, an interpolation curve of each section, that is, an interpolated position vector P (t) is obtained, thereby obtaining an expression representing the entire joint line. The control unit 3 records the tangent vectors T _k (k = 1 to n) of the measurement points P _{1 to} P _n and the interpolated position vector P (t) of each section in the recording unit.

In step S7, the control unit 3 uses the tangent vectors T _k (k = 1 to n) of the _n measurement points P _{1 to} P _n obtained in step S6 to calculate a tangent vector between two adjacent points. Interpolate in the same manner as in step S6.

Assuming that the tangent vectors of the two points P _i and P _{i + 1} are T _i and T _{i + 1} , and the change vectors of the tangent vectors at these two points are S _i and S _{i + 1} , the two adjacent points P _i and P _i The tangent vector T (t) (vector) between ₊₁ is given by Equation 4 using a cubic equation of parameter t.
T (t) = (2T _i -2T _{i + 1} + S _i + S _{i + 1} ) t ³ + (3T _{i + 1} -3T _i -2S _i -S _{i + 1} ) t ² + S _i t + T _i (Formula 4)
Here, t is 0 ≦ t ≦ 1, and Equation 4 holds for each component of the vector.

If this is applied to _n measurement points P _{1 to} P _n and a natural condition is set, that is, if the second derivative of the tangent vector T (t) is zero at the start and end points, Equation 5 Is obtained.

制御部３は、ステップＳ６において得られた測定点Ｐ₁〜Ｐ_nの接線ベクトルＴ₁〜Ｔ_nを記録部から読み出し、接線ベクトルの変化ベクトルＳ_k（ｋ＝１〜ｎ）について式５を解く。制御部３は、その結果を式４に適用して、各区間を補間する接線ベクトルＴ(ｔ)を決定し、記録部に記録する。

The control unit 3 reads the tangent vectors T _{1 to} T _n of the measurement points P _{1 to} P _n obtained in step S6 from the recording unit, and uses Equation 5 for the tangent vector change vectors S _k (k = 1 to n). solve. The control unit 3 applies the result to Equation 4 to determine a tangent vector T (t) for interpolating each section, and records it in the recording unit.

In step S8, using the measuring device 5, the positions of the three points on the workpiece surface measured at each vicinity of the n-number of measurement points P ₁ to P _n measured in step S5, the control unit 3, the measurement The position data of these three points are acquired from the device 5, the perpendicular direction to the plane (tangent plane) determined by these three points is calculated, and the normal vector N _k (k = 1 to n) at the measurement point P _k is obtained. Record in the recording unit. An example is shown in FIG. In Figure 4, in the vicinity of the measurement point P _k, 2 points P to the joint line across the measuring points P _{k k-,} sets the P _{k +,} and to set the point P _k0 out of the bond line, these The normal vector of the tangent plane determined by the three points is N _k .

In step S9, using the normal vectors N _k (k = 1 to n) of the _n measurement points P _{1 to} P _n obtained in step S8, a tangent vector between two adjacent points is obtained in step S6, Similar to S7, it is determined by interpolation.

If the normal vectors of the two points P _i and P _{i + 1} are N _i and N _{i + 1} , and the change vectors of the normal vectors at these two points are R _i and R _{i + 1} , the two adjacent points P _i , A normal vector N (t) (vector) between P _{i + 1} is given by Equation 4 using a cubic equation of parameter t.
N (t) = (2N _i −2N _{i + 1} + R _i + R _{i + 1} ) t ³ + (3N _{i + 1} −3N _i −2R _i −R _{i + 1} ) t ² + R _i t + N _i (Formula 6)
Here, t is 0 ≦ t ≦ 1, and Equation 6 holds for each component of the vector.

If this is applied to _n measurement points P _{1 to} P _n and natural conditions are set, that is, the second derivative of the normal vector N (t) is zero at the start and end points, 7 is obtained.

制御部３は、ステップＳ８において記録した測定点Ｐ₁〜Ｐ_nの法線ベクトルＮ₁〜Ｎ_nを記録部から読み出し、法線ベクトルの変化ベクトルＲ_k（ｋ＝１〜ｎ）について式７を解く。制御部３は、その結果を式６に適用して、各区間を補間する法線ベクトルを決定し、記録部に記録する。

The control unit 3 reads the normal vectors N _{1 to} N _n of the measurement points P _{1 to} P _n recorded in step S8 from the recording unit, and formula 7 for the normal vector change vector R _k (k = 1 to n). Solve. The control unit 3 applies the result to Equation 6 to determine a normal vector for interpolating each section and records it in the recording unit.

As described above, in steps S5 to S9, the position vector P _k (k = 1 to n), the position vector P (t) for interpolating between them, and the tangent vector T _k (k = 1 to n) for the entire joint line. And the tangent vector T (t) that interpolates between them, the normal vector N _k (k = 1 to n), and the normal vector N (t) that interpolates between them are the coordinate system of the measuring device 5 Determined by UVW.

  In step S10, the control unit 3 calculates probe attitude control data, that is, the tilt direction of the probe to be moved along the joining line. First, the control unit 3 calculates the tilt direction of the probe using a predetermined advance angle α and a tangent vector and normal vector at the start point. Here, the tilt direction of the probe is a direction tilted by a forward angle α from the normal vector direction in a plane determined by the tangent vector and the normal vector. For example, in the coordinate system UVW of the measuring apparatus, the W axis Is specified by an inclination angle θ from the rotation angle and a rotation angle φ from the U axis (see FIG. 5). Then, while gradually increasing the parameter t, the control unit 3 similarly uses the advance angle α, the tangent vector T (t), and the normal vector N (t) to probe inclination directions (θ (t), φ ( t)) is calculated to the end of the joining line.

  In step S11, the control unit 3 uses the transformation parameters M and L determined in step S4 for the attitude control data (position vector and probe tilt direction) in the coordinate system UVW of the measuring apparatus determined as described above, using Equation 1 Is converted into data in the coordinate system XYZ of the FSW device and recorded in the recording unit.

  Through the above steps S1 to S11, the control unit 3 was able to determine data necessary for posture control of the probe 1 in the FSW device. Therefore, in step S12, the control unit 3 transmits the posture control data to the drive unit 2, and the drive unit 2 directly controls the posture of the probe 1 to execute friction stir welding along the joining line.

  In step S13, it is determined whether or not there is a next workpiece to be joined. If not, the process ends. If there is, the process proceeds to step S14, and the relative position change between the FSW apparatus and the measuring apparatus 5 is performed. It is determined whether or not there was. If there is a relative position change, the process returns to step S1 to start the processing from the determination of the coordinate conversion parameter. If there is no position change, the coordinate conversion parameters M and L determined in the previous step S4 can be used as they are. Therefore, the process returns to step S5, the next work is mounted on the mounting table 4, and a series of processes for obtaining the attitude control data of the probe is performed.

  As described above, the process for obtaining the conversion parameters of the two coordinate systems may be executed only once when the measuring apparatus is newly fixed to the FSW apparatus, and thereafter the positional relationship between the measuring apparatus and the FSW apparatus. As long as does not change, the same coordinate transformation parameters M and L may be used.

  In the above description, in order to determine the coordinate conversion parameter, the case where a flat plate is installed on the mounting table and a predetermined hole is formed in the plate is described. However, the present invention is not limited thereto, and a predetermined point on the flat plate surface is marked. In addition, the position of the mark may be measured with a measuring device. Furthermore, without using auxiliary means such as a flat plate, the probe pin is moved to four points determined so that three or more points do not line up on a straight line, and the position coordinates of the probe tip are measured at each position. You may measure with an apparatus.

  In the above-described spline interpolation, the case where the natural condition is set has been described. However, the present invention is not limited to this, and a fixed condition may be set, that is, the value of the first derivative at the start point and the end point may be specified.

  When the workpiece to be connected is a flat plate, the workpiece normal direction coincides with the vertical axis of the FSW device, so that the advancing direction and advancing angle of the probe can be set even if steps S8 and S9 in FIG. 2 are omitted. .

  Further, the process shown in FIG. 2 can be performed with various changes. For example, in step S5 and step S8, coordinate conversion may be performed using the conversion parameter determined in step S4, and the subsequent processing may be performed in the coordinate system of the FSW device. In that case, the coordinate conversion in step S11 is unnecessary.

  In the above description, the case where a plurality of measurement points on the joining line are interpolated to determine the shape of the entire joining line has been described. However, the present invention is not limited to this, and it is sufficient that the joining line can be reproduced, such as NURBS. An interpolation process can be used.

It is a block diagram which shows schematic structure of an FSW apparatus in embodiment of this invention. It is a flowchart which shows the process which calculates | requires the data for the attitude | position control of the probe in the FSW apparatus which concerns on this Embodiment. It is a perspective view explaining the measurement point and tangent vector on a joining line. It is a perspective view explaining how to obtain a normal vector on a joint line. It is a perspective view which shows the relationship between a tangent vector, a normal vector, an advance angle, and the attitude | position of a probe.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Probe 2 Drive part 3 Control part 4 Platform 5 Measuring device

Claims (10)

A friction stir welding apparatus comprising a probe, a drive means for the probe, and a control means,
The control data for determining the posture of the probe includes first control data at a plurality of measurement points on the joint line of the object to be joined, and second at an interpolated position on the joint line between two adjacent measurement points. Control data, and
The control means is
Calculating the first control data using a plurality of measurement point position vectors, normal vectors, and a predetermined advancing angle;
Using the position vector and the normal vector of the plurality of measurement points, an interpolation position vector, an interpolation tangent vector, and an interpolation normal vector corresponding to the joint line between two adjacent measurement points are calculated by interpolation. And
Using the interpolation position vector, the interpolation tangent vector, the interpolation normal vector and the advance angle, calculate the second control data,
A friction stir welding apparatus, wherein the driving means is controlled using the first control data and the second control data to control the posture of the probe. The position vector and the normal vector of the previous measurement point are data measured by a measuring unit having a second coordinate system different from the first coordinate system of the friction stir welding apparatus,
The control data is data in the second coordinate system;
The measuring means measures the position of each of the four points where the coordinate data in the first coordinate system is known and determined so that three or more points are not aligned on the same line;
The control means uses the position data of the four points obtained by the measuring means and the known coordinate data of the four points, and a coordinate conversion parameter from the second coordinate system to the first coordinate system. Seeking
The friction stir welding apparatus according to claim 1, wherein the control means converts the control data into data in the first coordinate system using the coordinate conversion parameter. The interpolated position vector is calculated by spline interpolation using all of the position vector at a predetermined boundary condition;
A tangent vector of the measurement point is obtained in the process of spline interpolation of the position vector,
The interpolated tangent vector is calculated by spline interpolation using all of the tangent vector at a predetermined boundary condition;
The normal vector is a vector perpendicular to a plane formed by two points on the joint line that sandwich the measurement point and one point outside the joint line in the vicinity of the measurement point;
The friction stir welding apparatus according to claim 1 or 2, wherein the interpolation normal vector is calculated by spline interpolation using all of the normal vectors under a predetermined boundary condition. The control data is
The interpolated position vector indicating the position of the tip of the probe;
The friction according to claim 1, wherein the friction is data indicating a direction inclined by the advance angle from the interpolation normal vector in a plane formed by the interpolation tangent vector and the normal vector. Stir welding device. A method for controlling the probe of a friction stir welding apparatus comprising a probe, a drive means for the probe, and a control means,
The control data for determining the posture of the probe includes first control data at a plurality of measurement points on the joint line of the object to be joined, and second at an interpolated position on the joint line between two adjacent measurement points. Control data, and
A first step in which the control means calculates the first control data using a position vector, a normal vector, and a predetermined advance angle of the plurality of measurement points;
The control means uses the position vector and the normal vector of the plurality of measurement points, and by interpolation, an interpolation position vector, an interpolation tangent vector, and an interpolation corresponding to the joint line between two adjacent measurement points A second step of calculating a normal vector;
A third step in which the control means calculates the second control data using the interpolation position vector, the interpolation tangent vector, the interpolation normal vector, and the advance angle;
A friction stir welding characterized in that the control means includes a fourth step of controlling the driving means by using the first control data and the second control data to control the posture of the probe. Method for controlling the probe of the apparatus. The position vector and the normal vector of the previous measurement point are data measured by a measuring unit having a second coordinate system different from the first coordinate system of the friction stir welding apparatus,
The control data is data in the second coordinate system;
A fourth step in which the measuring means measures the position of each of the four points where the coordinate data in the first coordinate system is known and determined so that three or more points are not aligned on the same line;
The control means uses the position data of the four points obtained by the measuring means and the known coordinate data of the four points, and a coordinate conversion parameter from the second coordinate system to the first coordinate system. A fifth step for obtaining
The control means further includes a sixth step of converting the control data into data in the first coordinate system using the coordinate conversion parameter;
6. The method for controlling a probe of a friction stir welding apparatus according to claim 5, wherein the sixth step is executed between the second step and the third step. The interpolated position vector is calculated by spline interpolation using all of the position vector at a predetermined boundary condition;
A tangent vector of the measurement point is obtained in the process of spline interpolation of the position vector,
The interpolated tangent vector is calculated by spline interpolation using all of the tangent vector at a predetermined boundary condition;
The normal vector is a vector perpendicular to a plane formed by two points on the joint line sandwiching the measurement point and one point outside the joint line in the vicinity of the measurement point;
The method of controlling a probe of a friction stir welding apparatus according to claim 5 or 6, wherein the interpolation normal vector is calculated by spline interpolation using all of the normal vectors under a predetermined boundary condition. . The control data is
The interpolated position vector indicating the position of the tip of the probe;
The friction according to claim 5, wherein the friction is data indicating a direction inclined by the advance angle from the interpolation normal vector in a plane formed by the interpolation tangent vector and the normal vector. Control method of probe of stir welding apparatus. A method of manufacturing a joined body using a friction stir welding apparatus provided with a probe, a driving means for the probe, and a control means,
A method for manufacturing a joined body, comprising controlling the posture of the probe by the control method according to claim 5 and performing friction stir welding along a joining line. In a friction stir welding apparatus provided with a probe, a drive means for the probe, and a control means,
The control data for determining the posture of the probe includes first control data at a plurality of measurement points on the joint line of the object to be joined, and second at an interpolated position on the joint line between two adjacent measurement points. Control data, and
In the control means,
A function of calculating the first control data using a plurality of measurement point position vectors, normal vectors, and a predetermined advance angle;
Using the position vector and the normal vector of the plurality of measurement points, an interpolation position vector, an interpolation tangent vector, and an interpolation normal vector corresponding to the joint line between two adjacent measurement points are calculated by interpolation. Function to
A function of calculating the second control data using the interpolation position vector, the interpolation tangent vector, the interpolation normal vector, and the advance angle;
A control program for a probe of a friction stir welding apparatus for realizing a function of controlling the driving means by using the first control data and the second control data to control the posture of the probe.

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