JPH0242615B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention measures the respective center positions of a hole component and a shaft component inserted into the hole component, and aligns the relative center positions of the hole component and the shaft component. The present invention relates to a positioning method, and particularly to a positioning method for aligning the centers of a hole component and a shaft component without contacting each other. [Background of the Invention] Conventionally, as shown in FIG.
In order to insert the shaft 2a of the shaft component 2 formed in such a size as to have a gap δ therein, the center position of the hole 1a of the hole component 1 and the center position of the shaft 2a of the shaft component 2 are positioned. The positioning method is based on JP-A-53-
63700 and published in the Nikkan Kogyo Shimbun published by Nikkan Kogyo Shimbun on October 12, 1980, is considered to be an effective method. Note that 2b shown in FIG. 13 is a flange portion. However, in the former method, when inserting the shaft component into the hole component, the shaft component hits the hole component and the center of the shaft component follows the center of the hole component due to the reaction force, and is inserted. In the latter method, the reaction force is detected by a force sensor and the posture of the wrist is controlled and inserted so that no force exceeding a certain force is generated, so when inserting the shaft part into the hole part, If it is not inserted smoothly, it is likely that one or both parts will be damaged. Particularly when the material is made of aluminum etc., it is easy to get scratched and generate dust.
This dust may cause serious accidents to the product. [Object of the Invention] The present invention solves the above-mentioned conventional problems, and provides positioning that allows the center position of a hole part and the center part of a shaft part to be measured and positioned with high accuracy without generating dust. The purpose is to provide a method. [Summary of the Invention] To achieve the above object, the present invention provides a method for inserting a shaft component having a cylindrical shaft into a cylindrical hole formed in a hole component, in which the shaft component to be inserted is held. A measuring jig is held in the hand, and the measuring jig is inserted between a plurality of fixed sensors arranged facing each other on the same plane, and the measuring jig is rotated while the hand and the measuring jig are rotated. The outer diameter is measured with a fixed sensor and the rotation center position of the hand is memorized in the fixed sensor, and then the hand and measuring jig are moved a predetermined distance and the measuring jig is inserted into the hole of the hole part. While rotating the measuring jig and the hand, measure the center position of the hole in the hole part at multiple locations on the center line of the hole using the measuring tool built into the measuring jig, and if the hole in the hole part is tilted, Rotate the hole part in one or both of the two orthogonal directions using the tilt correction table, and after correction, measure the center position of the hole in the hole part again using the measuring tool to make sure that the tilt of the hole part is zero. The center position of the hole in the hole part is measured when the hole part is bent, and the relative position between the rotation center position of the hand and the center position of the hole in the hole part is then detected. Remove it, attach the shaft part, insert the shaft part between the above fixed sensors,
The outer diameter of the shaft component is measured with the above fixed sensor without rotating, and the deviation between the rotation center position of the hand and the center position of the shaft component is calculated from the rotation position of the hand when inserted between the above fixed sensors. The present invention is characterized in that the center position of the hole of the hole part and the center position of the fitting shaft part of the shaft part are determined by correcting the distance to the center position of the hole of the hole part. [Embodiments of the Invention] The following describes embodiments of the present invention with reference to FIGS. 1 to 12. Fig. 1 is a front view of a measuring device showing an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a partially sectional front view showing the measuring jig, and Fig. 4 is A of Fig. 3. 5 is a partially sectional front view showing the state where the measuring jig is attached to the hand, and FIG. 6 is a side view taken from B- in FIG.
FIG. 7 is a partially sectional front view showing the state in which the shaft component is attached to the hand; FIG. 8 is a perspective view showing the tilt correction table; FIG. 9 is an operation explanatory diagram; FIG. Figure 7a is an enlarged plan view, Figure 11 is the 1st
FIG. 12 is an explanatory view showing the measurement of the center position of the hole part. In the same figure, 4 is a base, and 5 is a table, which is supported on the upper surface of the base 4 so as to be slidable in the front-back direction (for convenience of explanation, the Y direction) with respect to FIG. 1, and a guide bar on the upper surface. 6 and supports both ends of a screw shaft (not shown) which is rotated by a drive mechanism (not shown). 7 is a column whose lower end is supported by the guide bar 6 so as to be slidable in the direction of the X arrow, and at the same time is screwed onto the screw shaft so that it can slide in the direction of the X arrow by rotation of the screw shaft. be moved. Further, the column 7 supports both ends of a vertical screw shaft 8 which is rotated by a drive mechanism (not shown). Reference numeral 9 is a robot, and two arms 9b are screwed onto the vertical plane of the triangular main body 9a at intervals to the vertical screw shaft 8.
is fixed, and a measuring jig 25 and hole component 1, which will be described later, are held on the upper surface via a hand 33, and a drive mechanism (not shown) for rotating the hand 33 is built inside. 10 is a mount, and the above base 4
It is fixed to both ends of the upper surface so as to surround the robot 9, and a ceiling plate 11 is fixed to the upper end. 12 is a fixed sensor unit, and the bottom part 12 is
The bottom part 12a is inserted and supported in a hole 11a formed in the ceiling plate 11 so as to protrude downward, and the bottom part 12a has a rectangular cylinder shape having a diameter of 4. It holds several fixed sensors 13. Further, a through hole 12b is formed in the center of the bottom portion 12a. Reference numeral 14 denotes a tilt correction table, which is fixed on the ceiling plate 11, and has three square-shaped bases 15, 16, 1 arranged so as to be stacked on top of each other as shown in FIG.
7 is provided. The lowermost base 15 has a stand 15a for supporting the motor 18 on one end surface thereof.
is fixed, and four protrusions 15b, each pair of which protrudes upward, are fixed at intervals on both ends of the upper surface of the other end. The central base 16 has two protrusions 16a fixed thereto at intervals above the motor 18 in the axial direction. This protrusion 16
a is the shaft end screw portion 18a of the motor 18;
A nut 19 is inserted therein, and two pins 20 protruding from both ends of the nut 19 are rotatably supported. Also, the base 1 in the center above
6 has two supporting parts 16b fixed to the other end thereof, which are inserted between the two protrusions 15b and rotatably supported via pins 21. Further, the base 17 in the center part has the two protrusions 16
A stand 16c for supporting the motor 22 is fixed to an end face perpendicular to the faces a and 16b, and four projections 16d, arranged in pairs, projecting upward at intervals, are fixed to both ends of the opposite end face. There is. The upper base 17 has two protrusions 17a fixed thereto at intervals above the motor 22 in the axial direction.
This protrusion 17a inserts a nut 23 into which the screw portion 22a of the shaft end of the motor 22 is screwed, and rotatably supports two pins 23a protruding from both ends of the nut 23. Further, the base 17 in the upper part has a supporting part 17 on which the hole part 1 is placed on the upper surface, and which is inserted between the protrusions 16d at the other end and rotatably supported via a pin 24.
b is fixed. Therefore, when the two motors 18 and 22 are driven and the screw portions 18a and 22a at the shaft ends rotate respectively, the tilt correction table 14 rotates through the nuts 19 and 23 to the base 16 at the center, The upper base 17 rotates about the pins 21 and 24 in the directions of arrows _θX and _θY , which are perpendicular to each other. can be tilted to Reference numeral 25 denotes a measuring jig, which includes a measuring jig main body 26, a distance sensor 27, and a support part 28.
, a slide portion 29 , and a positioning portion 30 . The measurement jig main body 26 includes, from above, a shaft-shaped jig 26a corresponding to the fitting shaft portion 2a of the shaft component 2, a first shaft portion 26b having a slightly smaller diameter than this jig 26a, and a first shaft portion 26b that is smaller in diameter than this jig 26a. A second shaft part 26d is formed to have a slightly large diameter and has a stepped hole 26c that penetrates in the left-right direction with respect to the inside of FIG. A flange portion 26e, a third shaft portion 26f formed with the smallest diameter, and a fourth shaft portion 26g formed with a slightly larger diameter than this third shaft portion 26f are fixed to each other on the same axis. It is formed. The distance sensor 27 is mounted on a fixing block 26h, which is fixed so that its shaft portion 27a is inserted into the stepped hole 26c on the upper surface of the flange portion 26d, via a leaf spring 31, as shown in FIG. A plunger 27b is fixed by a bolt 32 and inserted into the shaft portion 27a so as to be movable in the axial direction so that its tip protrudes outward. The plunger 27b is engaged with the upper portion of the slide member 29d of the slide portion 29. . The support part 2
8 has a shape, and its upper end is fixed at a position below a hole 26i formed to vertically penetrate through the flange portion 26d. The slide portion 29 includes a motor 29a fixed upright to the bottom portion 28a of the support portion 28, and a motor 29a fixed to the bottom portion 28a of the support portion 28 in an upright state.
Eccentric cam 29b fixed to the upper shaft end of 9a
and a cam follower 29c that is in contact with this cam 29b.
A slide member 29d fixes the cam fluoro 29c to the lower end thereof, and a protrusion plate 29e that protrudes horizontally from the center of the slide member 29d slidably supports the lower surface thereof and is fixed to the support portion 28. Slide bearing 29e and the slide member 2
9d and a spring 29f that is inserted between the inner end surface of the hole 26i of the flange portion 26e and keeps the cam follower 29c always in contact with the outer peripheral surface of the eccentric cam 29b. The above positioning part 3
0 fixes the fourth shaft part 26g of the measuring jig main body 26 to the center of the upper surface of the flange part 30a, fixes the stepped shaft 30b to the center of the lower surface, and has a rotating shaft on the outer periphery so as to protrude downward. Rod 30 for dynamic angle positioning
c is fixed. . Two ball bearings 30e are rotatably supported in the vertical direction on the lower small diameter portion 30d of the stepped shaft 30b. 33 is a hand held by the robot 9 at the bottom 33.
A main body 33a, which has a cylindrical shape having a cylindrical shape and has an upper surface that is in contact with the lower surfaces of the flange portion 2b of the shaft component 2 and the flange portion 26e of the measuring jig 25 , and a chuck that vertically passes through the center of the bottom portion 33b. 33c and a positioning tool 3 that holds the lower end of the rotation angle positioning rod 30c of the measurement jig 25 .
3d is fixed. The chuck portion 33c has a cylinder 33e and a piece 33g which is fixed to the tip of the piston rod 33f of the cylinder 33e and whose tip end surface is formed into a conical shape. Two chucks 33j are rotatably supported and have a cutout surface 33i whose lower end is in contact with the conical surface of the piece 33g.
is formed from. Therefore, the above hand 33
When holding the shaft component 2, the shaft component 2 is inserted into the main body 33a so that the lower surface of the flange portion 2b is in contact with the upper surface of the main body 33a, and the lower shaft portion is inserted between the upper portions of the chucks 33j. cylinder 3
When fluid is supplied to the piston rod 3e and the piece 33g at the tip of the piston rod 33f is inserted between the lower parts of the chuck 33j, the chuck 33j rotates and fastens the shaft part 2 between its upper parts. When holding the measuring jig 25, insert the measuring jig 25 into the main body 33a so that the lower surface of the flange portion 26e is in contact with the upper surface of the main body 33a, and insert the ball bearing 30e between the upper parts of the chucks 33j. included,
After inserting the lower end of the rod 30c between the upper parts of the positioning part 33d, the measuring jig 25 can be fastened in the same manner as in the case of the shaft component 2 described above. With the above configuration, after holding the hand 33 to which the measuring jig 25 is fastened by the main body 9a of the robot 9, a command value _X1 is given to the robot 9 and the
As shown in FIG. Next, when the robot 9 is moved upward and the jig 26a of the measuring jig 25 is inserted between the four fixed sensors 13, the tips of the four fixed sensors 13 are inserted simultaneously while rotating the jig 26a. the center position of the jig 26a is measured. In this case, as shown in FIG. 9a, the center position of the measuring jig 26a and the center position of the fixed sensor 13 may not match. This may be due to mismatch between the intersections of the four fixed sensors 13 and the center point of the hand 33, or due to poor attachment of the measuring jig 25 when the measuring jig 25 is fastened to the hand 33. Therefore, in the present invention, the hand 33 is rotated by 270 degrees and the specific point A of the measuring jig 26 of the measuring jig 25 is measured by the four fixed sensors 13, and the value is reset to 0. The center position of the hand 33 when the robot 9 moves a predetermined distance in the X direction from the initial position is stored in the four fixed sensors 13. Next, the robot 9 is lowered once, a command value X ₂ is given to the robot 9, and the robot 9 is moved in the X direction to move the measuring jig 25 to a position below the hole part 1.
Raise the robot 9 and place the measuring jig 25 in Fig. 9b.
As shown in the figure, insert it into the hole 1a of the hole jig 1. In this state, the hand 33 is rotated and the motor 2 is rotated at the same time.
9a to drive the plunger 27 of the distance sensor 27.
When the tip of b is pressed against the inner circumferential surface of the hole 1a of the hole jig 1, as shown in FIG. Δx ₁ ′ is measured. As shown in the figure,
In some cases, the hole part 1 is tilted by an angle α due to poor installation. Therefore, in the present invention, the distance sensor 27 is first positioned at Z ₁ to measure the distance, and then the measuring jig 25 is raised by the height H and the distance sensor 27 is
Position 7 at Z ₂ and measure. Both points at this time
If the deviation amounts Δx ₁ ′ and Δx ₁ ″ in Z ₁ Z ₂ are Δx ₁ ′=Δx ₁ ″, then the center line of the hole 1a of the hole part 1 and the hand 3
Even if there is a deviation amount Δx ₁ ′, Δx ₁ ″ in the center point on the plane at each point Z ₁ Z ₁ , there is no inclination of the hole part 1.On the other hand, Δx When ₁ '≠Δx ₁ '', the center line of the hole 1a of the hole part 1 is α=tan ^-1 with respect to the rotation center line of the hand 33.
It is tilted by Δx ₁ ′+Δx ₁ ″/H. Therefore, in this case, either motor 18 or 22 or both motors 1 of the tilt correction table 14
8 and 22 to correct the inclination of the hole part 1, and again position the distance sensor 27 at Z ₁ and Z ₂ to measure the deviation amounts Δx ₁ ′ and Δx ₁ ″ at each position Z ₁ Z ₂ . ,
This is repeated until Δx ₁ ′=Δx ₁ ″.Then, when the sensor 27 is located at Z ₁ and Z ₂ , the respective deviation amounts Δx ₁ ′ and Δx″ become Δx ₁ ′=Δx ₁ ″. The distance X to the center point of the hole 1a of the hole part 1 when it reaches the center point is X=X ₂ +Δx ₁ ...(1).Then, the robot 9 is lowered and
is returned to the initial position, the measuring jig 25 is removed from the hand 33, and the shaft component 2 is fastened, as shown in FIG. 9c. After that, a command value _X1 is given to the robot 9, and the robot 9 is moved to a position below the four fixed sensors 13 as shown in FIG. fixed sensor 13
As shown in FIG.
The measurement is performed using the fixed sensors 13. As described above, the reason why the hand 33 and the measuring jig 25 rotate when the measuring jig 25 is used, but not when the shaft component 2 is used is that, for example, the position when the shaft component 2 is fastened to the hand 33 with the chuck 33m is Due to the misalignment, the center of the shaft component 2 will shift with respect to the center of the hand 33. At this time, the centers of the four fixed sensors 13 relative to the center of the hand 33 have already been reset to 0 as described above, so if the outer diameter is measured in a fixed state without rotating the hand 33, the shaft part 2 The amount of deviation Δx ₂ and Δy ₂ between the center of the hand 33 and the center of the hand 33 can be measured. Therefore, in order to align the center position of the shaft part 2 with the center position of the hole 1a of the hole part 1 as shown in FIG. 9b, the command value _X0 given to the robot 9 is _X0 = X- _Δx2 ... ...(2), and from the above first and second equations, X ₀ =X ₂ +(Δx ₁ −Δx ₂ ) ...(3). Therefore, by moving the shaft component 2 by the command value X ₀ , the mating shaft portion 2a of the shaft component 2 can be inserted into the hole portion 1a of the hole component 1 in a non-contact state. In this case, since the length on the order of microns is a problem, the weight of the measuring jig 25 is particularly important when the strain generated in the hand 33 that supports it due to the increased weight of the shaft component becomes a problem. By making the weight the same as that of the shaft part 2, the center of the hole part 1a of the hole part 1 and the shaft part 2a of the shaft part 2 that fits
It is possible to accurately position the center of the As described above, even if the gap between the hole part of the hole part and the fitting shaft part of the shaft part is small, the fitting shaft part of the shaft part can be moved into the hole part of the hole part in a non-contact state. Since it can be inserted into the section, it has the following effects. (b) The quality and performance of the product can be improved by implementing the present invention in cases where the dust generated during assembly of the product, even micron or submicron dust, has a significant impact on the quality and performance of the product. be able to. (b) If the weight of the shaft component is large, if you manually hold the shaft component and insert the mating shaft section into the hole of the hole component, it may cause twisting or dust to occur between the two, and the insertion operation may not be smooth. However, the present invention can solve all of these problems. (c) When accuracy on the micron order becomes a problem, it is necessary to consider the effects of thermal expansion. In such a case, the present invention resets the center position of the hand each time the measuring jig is inserted into the fixed sensor, and uses the measuring jig to determine the relative position between the rotation center of the hand and the center of the hole in the hole part. is measured with a fixed sensor, and the movement of the hand, measuring jig, and shaft parts is controlled using information about the relative positions at this time, so large temperature changes during the short measurement time are almost impossible. Therefore, in the present invention, the influence of thermal expansion can be prevented. (d) When measuring the center position of the hand with a fixed sensor via a measurement jig, rotate the hand and the measurement jig so that the rotation center position of the hand is always used as a reference, and when measuring shaft parts with a fixed sensor, Since the shaft part is fixed, the chuck error when checking the measuring jig with the hand will not be affected, and conversely, the chuck error when checking the shaft part with the hand or the product between the chuck part and the part to be measured will not be affected. Measurement can be performed taking the above error into consideration, thereby making it possible to accurately match the relative center positions of the hole of the hole component and the fitting shaft portion of the shaft component.

[Brief explanation of the drawing]

Fig. 1 is a front view of a measuring device showing an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a partial sectional view showing the measuring jig, and Fig. 4 is a side view taken in the direction of arrow A. ,
Fig. 5 is a partial cross-sectional front view showing the measurement jig attached to the hand, Fig. 6 is a plan view taken along the line B-B in Fig. 5, and Fig. 7 shows the shaft part attached to the hand. 8 is a perspective view showing the tilt correction table, FIG. 9 is an explanatory diagram of the operation, FIG. 10 is an enlarged plan view of FIG. 9 a, and FIG. 11 is an enlarged view of FIG. 9 d. A plan view, FIG. 12 is an explanatory diagram showing the time of measuring the center position of the hole component, and FIG. 13 is a sectional view showing the hole component and the shaft component. 1... Hole part, 1a... Hole, 2... Shaft part, 2
a...Shaft portion, 4...Base, 5...Table, 7
... Column, 9 ... Robot, 12 ... Fixed sensor unit, 13 ... Fixed sensor, 14 ... Tilt correction table, 25 ... Measurement jig, 26 ... Measurement jig body, 27 ... Distance sensor, 28... Support tool, 29... Slide portion.

Claims (1)

[Claims] 1. In a method of inserting a shaft part having a cylindrical shaft part into a cylindrical hole formed in a hole part, a measuring jig is held by the hand holding the shaft part to be inserted, and the measuring jig is is inserted between a plurality of fixed sensors arranged facing each other on the same plane, and while rotating the hand and measuring jig, the outer diameter of the measuring jig is measured with the fixed sensor, and the rotation of the hand is thereby performed. The center position is stored in the fixed sensor, and then the hand and the measuring jig are moved a predetermined distance and the measuring jig is inserted into the hole of the hole part, and the measuring jig is rotated while the measuring jig and the hand are being rotated. If you measure the center position of a hole in a hole component at multiple locations on the center line of the hole using the built-in measuring tool, and the hole in the hole component is tilted, use the tilt correction table to measure the center position of the hole in two directions orthogonal to each other. Rotate either or both of them, and after correction, measure the center position of the hole in the hole part again with the above measuring tool, and measure the center position of the hole in the hole part when the inclination of the hole part becomes zero. Then, the relative position between the rotation center position of the hand and the center position of the hole of the hole part is detected, and then the measuring jig is removed from the hand, the shaft part is attached, and the shaft part is fixed as described above. The sensor is inserted between the sensors, and the outer diameter of the shaft component is measured with the above fixed sensor without rotation, and the amount of deviation between the rotation center position of the hand and the center position of the shaft component is measured by inserting it between the above fixed sensors. The center position of the hole in the hole part and the center position of the fitting shaft part of the shaft part are determined by correcting the distance from the rotation position of the hand to the center position of the hole in the hole part. Positioning method.