JP2022129888A - Positioning method and positioning device - Google Patents

Abstract

To provide a positioning method and a positioning device capable of accurately and inexpensively performing the positioning of a detector to the center position.SOLUTION: A positioning method includes: a matching step of rotating a detector in a second rotation direction and matching a tip position of a stylus projecting from the bottom surface with the bias of a biasing member to a height position of the bottom surface when the detector is in the center position; first contact steps S3-S5 in which the tip of the stylus is brought into contact with the surface to be measured by moving the detector relative to the surface to be measured in a state where the tip position of the stylus is matched with a height position; and a second contact step in which the detector is rotated in a first rotation direction and the bottom surface is brought into contact with the surface to be measured after completion of the first contact step.SELECTED DRAWING: Figure 6

Description

The present invention relates to a positioning method and positioning apparatus for positioning a detector of a surface profile measuring machine at the center position of its swing range.

2. Description of the Related Art A surface profile measuring machine is known for measuring surface profile such as surface roughness and contour profile of a surface to be measured of a work. This surface shape measuring instrument includes a stylus mounted swingably around a swing fulcrum, a detector having a stylus or the like provided at the tip of the stylus, and a detector swingably supported. and a drive unit that moves along the surface to be measured. The surface profile measuring machine traces the surface to be measured with the stylus by moving the detector and the surface to be measured in the horizontal direction by the driving unit while the stylus of the detector is in contact with the surface to be measured. The displacement of the stylus (stylus) is detected. The surface shape of the surface to be measured is obtained based on the displacement detection result.

As such a surface shape measuring instrument, a skid measuring instrument that traces the surface to be measured with a stylus while the skid attached to the detector is in contact with the surface to be measured is well known (patent See Document 1 and Patent Document 2). This profilometer can detect displacement of the stylus relative to the skid.

In recent years, there is an increasing need for automation of surface profile measurement using a surface profile measuring machine. Therefore, after controlling the robot arm that holds the surface profile measuring machine to bring the stylus of the detector into contact with the surface to be measured by the robot arm, the driving unit is driven to move the detector to the surface to be measured. The surface profile can be automatically measured by relatively moving in the horizontal direction (see Patent Document 3).

JP 2013-257167 A Japanese Patent No. 6458335 Japanese Patent No. 6800421

By the way, as described in Patent Document 3, when performing surface shape measurement by a surface shape measuring machine using a robot arm, in order to prevent the vibration of the robot arm from affecting the measurement result of the surface shape measurement, Therefore, it is desirable to use the skid measurement type surface shape measuring machine described in Patent Documents 1 and 2 above. Since the skid is in constant contact with the surface to be measured, the influence of the vibration of the robot arm on the measurement results of the surface profile measurement can be reduced.

However, when surface profile measurement is performed using a skid measurement type surface profile measuring instrument, the detector is positioned at the center of its swing range (movable range) while the skid is in contact with the surface to be measured. There is a need. Therefore, when the skid of the detector is brought into contact with the surface to be measured by the robot arm, it is necessary to teach the robot arm so that the detector is positioned at the center position. It is generally performed by a method that relies on visual observation. As a result, it takes time to teach the robot arm, the positioning accuracy of the central position of the detector varies from operator to operator, or the detector is damaged by pressing it too much against the surface to be measured. It is possible.

In addition, instead of visually instructing the robot arm, a detection switch (detection sensor) capable of detecting whether the detector is at the center position is provided in the surface shape measuring machine, and detection is performed based on the detection result of this detection switch. A method of teaching the robot arm so that the instrument is positioned at the center position is also conceivable. However, this method has the problem that the detection switch and its wiring must be added to the profilometer, which increases the cost. There is also the problem of the need to position the detection switch.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a positioning method and a positioning apparatus capable of positioning a detector at a central position with high accuracy and at low cost.

A positioning method for achieving the object of the present invention comprises: a skid having a bottom surface in contact with a surface to be measured and a through hole opening in the bottom surface; a stylus inserted into the through-hole provided at the tip of the stylus that approaches the skid when rotated in one rotational direction and moves away from the skid when rotated in a second rotational direction opposite to the first rotational direction; an urging member that urges the stylus in the first rotational direction; the detector is held to be swingable in the first and second rotational directions; and a drive unit that moves in a drive direction perpendicular to the axial direction, in which the detector is positioned at the center of the swing range of the detector when the skid is brought into contact with the surface to be measured. In the method, the detector is rotated in the second rotation direction, and the position of the tip of the stylus protruding from the bottom surface due to the biasing of the biasing member is adjusted to the height position of the bottom surface when the detector is at the center position. A first contact step of matching the tip position of the stylus with the height position and moving the detector relative to the surface to be measured to bring the tip of the stylus into contact with the surface to be measured. and, after completing the first contacting step, a second contacting step of rotating the detector in the first rotational direction to bring the bottom surface into contact with the surface to be measured.

According to this positioning method, the center of the detector can be detected without relying on the operator's visual observation or providing the surface profile measuring machine with a detection switch (detection sensor) capable of detecting whether or not the detector is at the center position. Positioning to a position can be performed.

In the positioning method according to another aspect of the present invention, the first contact step moves the detector relative to the surface to be measured, and moves one of the tip of the stylus and the surface to be measured toward the other. a detecting step of continuously detecting presence or absence of displacement of the stylus while the moving step is being executed; a stopping step of stopping the moving step when displacement of the stylus is detected in the detecting step; including. As a result, the detector can be positioned at the central position without relying on the operator's visual observation or providing the surface profile measuring machine with a detection switch capable of detecting whether the detector is at the central position. can.

In the positioning method according to another aspect of the present invention, in the moving step, the robot that holds the surface profile measuring machine and can change the position and orientation of the surface profile measuring machine is controlled to direct the detector toward the surface to be measured. move.

In the positioning method according to another aspect of the present invention, in the matching step, the holder is detachably attached to the drive unit, and the detector is pressed by the holder to rotate the detector by a certain angle in the second rotation direction, thereby rotating the stylus. is aligned with the height position, and rotation regulation is performed by the holder to regulate the rotation of the detector in the first rotation direction, and in the second contact step, the holder is removed from the drive unit to release the rotation regulation By doing so, the detector is rotated in the first rotation direction.

A positioning device for achieving the object of the present invention comprises a skid having a bottom surface in contact with a surface to be measured and a through hole opening in the bottom surface; a stylus inserted into the through-hole provided at the tip of the stylus that approaches the skid when rotated in one rotational direction and moves away from the skid when rotated in a second rotational direction opposite to the first rotational direction; an urging member that urges the stylus in the first rotational direction; the detector is held to be swingable in the first and second rotational directions; and a drive unit that moves in a drive direction perpendicular to the axial direction, in which the detector is positioned at the center of the swing range of the detector when the skid is brought into contact with the surface to be measured. A device, which is a holder attached to a drive unit, and is switchable between a pressed state in which the detector is pressed and rotated in the second rotation direction, and a pressed state in which the detector is released from the pressed state. a relative movement unit that relatively moves the detector with respect to the surface to be measured; a switching control unit that controls switching between the pressing state and the pressing release state of the holding device; a movement control unit that drives the relative movement unit to move one of the tip of the stylus and the surface to be measured toward the other when the relative movement unit is switched to the state, and displaces the stylus while the relative movement unit is being driven. and a displacement detector for continuously detecting the presence or absence of the stylus. , the movement control unit stops driving the relative movement unit when the displacement detection unit detects displacement of the stylus, and the switching control unit causes the movement control unit to drive the relative movement unit is stopped, the holder is switched from the pressed state to the released state to rotate the detector in the first rotation direction and bring the bottom surface into contact with the surface to be measured.

In the positioning device according to another aspect of the present invention, the relative moving part is a robot that holds the surface profile measuring machine and can change the position and orientation of the surface profile measuring machine.

The present invention enables the positioning of the detector to the central position with high precision and low cost.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic which showed an example of the surface-roughness measuring system of 1st Embodiment. It is an enlarged view of the tip portion of the robot arm. It is an enlarged view of the detector of the surface roughness measuring machine. FIG. 4 is an explanatory diagram for explaining generation of teaching information for each surface to be measured; It is an explanation for explaining a problem at the time of generation of teaching information. 5 is a flow chart showing the flow of a positioning method for positioning a detector at a central position when generating teaching information for a surface to be measured; FIG. 7 is an explanatory diagram for explaining step S1 in the flowchart shown in FIG. 6; FIG. 7 is an explanatory diagram for explaining steps S2 and S3 in the flowchart shown in FIG. 6; FIG. 7 is an explanatory diagram for explaining steps S4 and S5 in the flowchart shown in FIG. 6; FIG. 7 is an explanatory diagram for explaining step S6 in the flowchart shown in FIG. 6; It is the schematic which showed an example of the surface roughness measuring system of 2nd Embodiment. 10 is a flow chart showing the flow of a positioning method for positioning a detector at a center position when generating teaching information for a surface to be measured in the second embodiment; FIG. 13 is an explanatory diagram for explaining step S1A in the flowchart shown in FIG. 12; 13 is an explanatory diagram for explaining steps S2A and S3A of the flowchart shown in FIG. 12; FIG. FIG. 13 is an explanatory diagram for explaining steps S4A and S5A of the flowchart shown in FIG. 12; FIG. 13 is an explanatory diagram for explaining step S6A in the flowchart shown in FIG. 12;

[First embodiment]
FIG. 1 is a schematic diagram showing an example of a surface roughness measuring system 10 of a first embodiment to which the positioning method of the invention is applied. In addition, the XYZ axes in the drawing are mutually orthogonal axes, the XY axis is an axis parallel to the horizontal direction, and the Z axis is an axis orthogonal to the horizontal direction. In this specification, "parallel" includes "substantially parallel", and "perpendicular" includes "substantially perpendicular".

As shown in FIG. 1, the surface roughness measuring system 10 includes a stage 12, a robot base 14, a robot arm 16, a surface roughness measuring instrument 18, and a controller 20, which holds the surface roughness measuring instrument 18. The robot arm 16 is used to measure the surface roughness of the surface Wa of the workpiece W to be measured.

On the stage 12, a workpiece W having a surface Wa to be measured, which is an object of surface roughness measurement, is placed, and a robot base 14 is installed.

<Robot base and robot arm>
The robot base 14 is arranged on the stage 12 at a position that does not interfere with the arrangement of the work W and the surface roughness measurement of the surface Wa to be measured by the surface roughness measuring device 18 . A robot arm 16 is provided on the robot base 14 . Note that the robot base 14 may be arranged outside the stage 12 .

The robot arm 16 corresponds to the robot and the relative moving part of the present invention, holds the surface roughness measuring machine 18, and detects the detector 30 (a stylus 48 and a skid to be described later) of the surface roughness measuring machine 18. 54, see FIG. 3) is brought into contact with a desired portion of the surface Wa to be measured. The robot arm 16 is a multi-joint type arm, and includes five arms 16a1 to 16a5, four joints 16b, and an end effector 16c. The number of arms (number of joints) of the robot arm 16 can be changed as appropriate.

The arm 16a1 is attached to the robot base 14 so as to be rotatable about the Z-axis via a movable shaft (rotary actuator) (not shown). ``Arm 16a1 and arm 16a2'', ``arm 16a2 and arm 16a3'', ``arm 16a3 and arm 16a4'', ``arm 16a4 and arm 16a5'', and ``arm 16a5 and end effector 16c'' are each connected to a joint 16b (rotary type). actuator) to be rotatable about an axis perpendicular to the Z-axis. Thereby, the robot arm 16 can freely change the position and orientation of the surface roughness measuring machine 18 .

FIG. 2 is an enlarged view of the tip portion of the robot arm 16. As shown in FIG. As shown in FIG. 2 and FIG. 1 already described, a surface roughness measuring machine 18 is held at the tip of the end effector 16c via an adapter 16d. The illustrated shape of the adapter 16d is an example, and the shape of the adapter 16d is not limited as long as the surface roughness measuring instrument 18 can be held.

The driving of each joint portion 16b of the robot arm 16 and the movable shaft is controlled by a control device 20, which will be described later.

<Surface roughness measuring machine>
FIG. 3 is an enlarged view of the detector 30 of the surface roughness measuring machine 18. As shown in FIG. The X1Y1Z1 axes in FIG. 3 are the coordinate axes of a coordinate system based on the surface roughness measuring machine 18, the X1 axis direction being parallel to the longitudinal direction of the detector 30, and the Z1 axis direction being the direction of the detector 30. This is the sensitivity direction, and the Y1-axis direction is a direction perpendicular to both the X1-axis direction and the Z1-axis direction. 1 and 2, the surface roughness is measured so that the X1-axis direction is parallel to the X-axis direction, the Y1-axis direction is parallel to the Y-axis direction, and the Z1-axis direction is parallel to the Z-axis direction. A machine 18 is held on the robot arm 16 .

As shown in FIGS. 1 to 3, the surface roughness measuring machine 18 corresponds to the surface shape measuring machine of the present invention, and includes a detector 30 (also referred to as a pickup), a nosepiece 32, and a drive section 34 (device). Also referred to as a main body).

The detector 30 has a shape extending in the X1-axis direction. This detector 30 is moved along the X1-axis direction (that is, the surface to be measured Wa) by the drive unit 34, so that the surface to be measured Wa is traced by the stylus 48, and the Z1-axis direction of the stylus 48 is traced. A detection signal indicating the displacement is output to the signal processing unit 52 (see FIG. 1).

The detector 30 includes a swing fulcrum 40, a stylus 42 (also referred to as an arm or probe), an urging member 44, a detection sensor 46, a stylus 48, and a housing 30a (also referred to as an arm) that accommodates these components. ) and

The swing fulcrum 40 has a rotating shaft (swing shaft) parallel to the Y1-axis direction. The swing fulcrum 40 supports the stylus 42 swingably.

The stylus 42 includes a stylus body portion 42a that is rockably supported by the rocking fulcrum 40, a stylus tip portion 42b that extends from the stylus body portion 42a to one side in the stylus longitudinal direction, and a stylus tip portion 42b that extends from the stylus body portion 42a in the stylus longitudinal direction. and a stylus proximal end portion 42c extending to the other side of the . The shape of the stylus 42 is not limited to the shape shown in FIG. 3, and may be changed as appropriate.

A stylus 48 is provided at the tip of the stylus tip 42b. The stylus 48 is a downward stylus that protrudes in one direction perpendicular or oblique to the stylus longitudinal direction of the stylus 42, that is, protrudes downward in the Z1-axis direction. The tip portion of the stylus tip portion 42b and the stylus 48 protrude from the housing 30a toward the nosepiece 32 and are accommodated in the nosepiece 32. As shown in FIG.

A core 46a that constitutes a part of a detection sensor 46, which will be described later, is provided at the stylus base end portion 42c.

The stylus 42 swings in a first rotation direction SW1 and a second rotation direction SW2 with the swing fulcrum 40 as a reference. The first rotation direction SW1 is the rotation direction in which the stylus tip 42b and the stylus 48 approach a skid 54, which will be described later. The second rotation direction SW2 is the rotation direction opposite to the first rotation direction SW1 and the rotation direction in which the stylus tip 42b and the stylus 48 move away from the skid 54. FIG.

The biasing member 44 biases the stylus base end 42c upward in the Z1-axis direction. Various springs such as a coil spring and a leaf spring are used as the biasing member 44 . Note that the stylus proximal end portion 42c may be biased by a known biasing method other than a spring. As a result, the stylus 42 and the stylus 48 are biased in the first rotation direction SW1 by the biasing member 44 about the swing fulcrum 40 .

A linear variable differential transformer, for example, is used as the detection sensor 46 . The detection sensor 46 is composed of a core 46a provided at the stylus base end 42c and a coil 46b provided inside the housing 30a.

The core 46a is an iron core extending downward in the Z-axis direction from the stylus base end 42c. The coil 46b is provided at a position below the stylus base end portion 42c in the Z1 axis direction. The core 46a is inserted into the coil 46b in a non-contact manner.

Although not shown, the coil 46b is composed of a primary coil and two types of secondary coils. When the primary coil of the coil 46b is excited by the control device 20, detection signals indicating the position (displacement) of the core 46a in the Z1-axis direction are sent from the two secondary coils via the signal cable 50 (see FIG. 2). It is output to the signal processing unit 52 (see FIG. 1). As a result, based on the positional relationship among the swing fulcrum 40, the stylus 42 (stylus 48), and the core 46a, and the position of the core 46a in the Z1-axis direction detected by the detection sensor 46, the stylus 42 (stylus 48) can detect displacement in the Z1-axis direction.

The nosepiece 32 is attached to the distal end side of the housing 30a. The nosepiece 32 is provided with a housing space for housing the tip portion of the stylus tip portion 42b and the stylus 48. As shown in FIG. Further, the nosepiece 32 is provided with a skid 54 at a position spaced downward in the Z-axis direction from the tip portion of the stylus tip portion 42b in the housing space.

The skid 54 has a skid bottom surface 54a, which is a bottom surface in contact with the surface Wa to be measured during surface roughness measurement, and a stylus insertion hole 54b (corresponding to the through hole of the present invention) that opens in the skid bottom surface 54a and through which the stylus 48 is inserted. ) and When the skid bottom surface 54a is not in contact with the surface to be measured Wa, the biasing member 44 biases the stylus 42 in the first rotation direction SW1, so that the stylus 48 passes through the stylus insertion hole 54b and moves from the skid bottom surface 54a to Z1. It protrudes axially downward by a certain amount. Conversely, when the skid bottom surface 54a is in contact with the surface Wa to be measured, the stylus 42 is rotated by a constant angle in the second rotation direction SW2 against the biasing force of the biasing member 44, thereby causing the stylus 48 to rotate. and the bottom surface 54a of the skid coincide with each other in the Z1-axis direction.

The drive unit 34 has a shape extending in the X1-axis direction like the detector 30, holds the detector 30 so as to swing in the first rotation direction SW1 and the second rotation direction SW2, and controls the detector 30. Under the control of device 20, detector 30 is moved in the X1-axis direction (corresponding to the driving direction of the present invention). Further, the drive unit 34 outputs a movement amount signal indicating the amount of movement when the detector 30 is moved in the X1-axis direction to the signal processing unit 52 via the signal cable 50 .

In addition, the drive unit 34 may be provided with a biasing member that biases the detector 30 in the first rotation direction SW1. Alternatively, when the detector 30 is rotated in the first rotation direction SW1 or the second rotation direction SW2 from the central position A1 of the swing range R as shown in FIG. An urging member or an elastic body may be provided.

The signal processing unit 52 is provided in the robot arm 16 , and amplifies the detection signal output from the detection sensor 46 and the movement amount signal output from the driving unit 34 as necessary, and then transmits the signal to the control device 20 . Output.

<Control device>
Returning to FIG. 1 , the control device 20 centrally controls the operation of the robot arm 16 and the surface roughness measurement of the surface Wa to be measured by the surface roughness measuring device 18 . Connected to the controller 20 are the robot arm 16 , the surface roughness measuring machine 18 , and the signal processing section 52 , as well as a storage section 60 , an operation section 62 , and a display section 64 .

The storage unit 60 stores a control program (not shown), teaching information 66 (teaching information) defining the positions and orientations of the robot arm 16 and the surface roughness measuring machine 18 when measuring the surface roughness of the surface Wa to be measured, and Measurement results of the surface roughness of the surface Wa to be measured, etc. are stored. The teaching information 66 is created in advance for each surface Wa of the workpiece W to be measured and stored in the storage unit 60 .

The operation unit 62 is used for various operations including manual operation of the robot arm 16, manual operation of the surface roughness measuring machine 18, operation of registering teaching information 66, and operation of starting surface roughness measurement.

The display unit 64 displays various setting screens, measurement results of the surface roughness of the surface Wa to be measured, and the like. Further, the display unit 64 visually displays the displacement of the stylus 48 when registering the teaching information 66 (see FIGS. 8 and 9 described later).

The control device 20 is configured by an arithmetic device such as a personal computer, for example, and includes an arithmetic circuit configured by various processors, memories, and the like. Various processors include CPU (Central Processing Unit), GPU (Graphics Processing Unit), ASIC (Application Specific Integrated Circuit), and programmable logic devices [for example, SPLD (Simple Programmable Logic Devices), CPLD (Complex Programmable Logic Device), and FPGAs (Field Programmable Gate Arrays)]. Various functions of the control device 20 may be realized by one processor, or may be realized by a plurality of processors of the same type or different types.

The control device 20 functions as a robot control unit 70, a measuring device control unit 72, a displacement detection unit 74, a displacement detection unit 76, and a surface shape analysis unit 78 by executing a control program read from the storage unit 60. .

A robot control unit 70 controls the operation of the robot arm 16 . When measuring the surface roughness of the surface Wa to be measured, the robot control unit 70 controls the robot arm 16 based on the teaching information 66 in the storage unit 60 to control the position and attitude of the surface roughness measuring machine 18, The stylus 48 and skid 54 of the detector 30 are brought into contact with the surface Wa to be measured. Further, the robot control unit 70 drives the robot arm 16 according to the manual operation of the operation unit 62 by the operator when generating the teaching information 66 for each surface to be measured Wa, which will be described later in detail.

The measuring machine control section 72 controls the operation of each part (the driving section 34 and the detection sensor 46) of the surface roughness measuring machine 18. FIG. When measuring the surface roughness of the surface Wa to be measured, the measuring instrument control unit 72 operates the detection sensor 46 after the stylus 48 and the skid 54 of the detector 30 are brought into contact with the surface Wa to be measured by the robot arm 16. By driving the drive unit 34 and moving the detector 30 in the X1-axis direction, the probe 48 scans the surface Wa to be measured. Further, the measuring machine control section 72 operates the detection sensor 46 when generating the teaching information 66 for each surface Wa to be measured.

The movement amount detection unit 74 detects the movement amount of the detector 30 based on the movement amount signal input from the driving unit 34 via the signal processing unit 52 when measuring the surface roughness of the surface Wa to be measured. The detection result is output to the surface shape analysis section 78 .

The displacement detection unit 76 detects the displacement of the stylus 48 in the Z1-axis direction based on detection signals continuously input from the detection sensor 46 via the signal processing unit 52 when measuring the surface roughness of the surface Wa to be measured. Continuous detection is performed, and the detection results are sequentially output to the surface shape analysis section 78 . Further, the displacement detection unit 76 sequentially outputs to the display unit 64 detection results indicating whether or not the stylus 48 is displaced in the Z1-axis direction when generating the teaching information 66 for each surface Wa to be measured.

When measuring the surface roughness of the surface Wa to be measured, the surface shape analysis unit 78 detects the amount of movement of the detector 30 input from the movement amount detection unit 74 and the displacement of the stylus 48 input from the displacement detection unit 76. Based on, the surface roughness of the surface to be measured Wa is calculated.

<Teaching information generation (teaching operation)>
FIG. 4 is an explanatory diagram for explaining generation of teaching information 66 for each surface Wa to be measured. As indicated by reference numerals C1 to C5 in FIG. 4, when measuring the surface roughness of each surface Wa to be measured of the workpiece W, teaching information 66 is generated for each surface Wa to be measured and stored in the storage unit 60. .

Specifically, the operator operates the operation unit 62 to manually drive the robot arm 16 to bring the stylus 48 and the skid 54 of the detector 30 into contact with the surface Wa to be measured. At this time, the robot control unit 70 drives the robot arm 16 according to the operator's operation, and provides the teaching information 66 with information on the movement of the robot arm 16 until the stylus 48 and the skid 54 contact the surface Wa to be measured. is stored in the storage unit 60 as. The teaching information 66 includes information indicating a measurement route including three-dimensional coordinates of target points and intermediate points.

Similarly, the teaching information 66 for each surface Wa to be measured is stored in the storage unit 60 by repeating the registration operation of the teaching information 66 for all the surfaces Wa to be measured.

FIG. 5 is an explanation for explaining a problem when generating the teaching information 66. FIG. When the teaching information 66 is generated, the stylus 48 and the skid 54 of the detector 30 are brought into contact with the surface to be measured Wa by the operator's manual operation. There is a risk that the surface roughness measuring machine 18 will be damaged if it is pressed too much. Conversely, as indicated by reference numeral 5B in FIG. 5, if the detector 30 is not pressed sufficiently, the skid 54 does not sufficiently contact the surface Wa to be measured, thereby degrading the surface roughness measurement accuracy.

Therefore, as indicated by reference numeral 5C in FIG. 5, when the stylus 48 and skid 54 of the detector 30 are brought into contact with the surface Wa to be measured, the detector 30 is moved to the central position A1 (neutral position) of its swing range R. ) must be positioned. Therefore, in this embodiment, the center position A1 of the detector 30 is detected without relying on the operator's visual observation or providing the surface roughness measuring machine 18 with a detection switch (detection sensor) for detecting the center position A1 of the detector 30. allows the positioning of Specifically, in this embodiment, the holder 80 (see FIG. 7), the detection sensor 46 and the stylus 48 are used to position the detector 30 at the central position A1.

[Positioning method of the first embodiment]
FIG. 6 is a flow chart showing the flow of the positioning method for positioning the detector 30 at the center position A1 when the teaching information 66 of the surface Wa to be measured is generated. FIG. 7 is an explanatory diagram for explaining step S1 in the flowchart shown in FIG. FIG. 8 is an explanatory diagram for explaining steps S2 and S3 of the flow chart shown in FIG. FIG. 9 is an explanatory diagram for explaining steps S4 and S5 of the flow chart shown in FIG. FIG. 10 is an explanatory diagram for explaining step S6 in the flowchart shown in FIG.

6 and 7, before bringing the stylus 48 of the detector 30 and the skid 54 into contact with the surface Wa to be measured, that is, the stylus 48 is positioned downward in the Z1-axis direction from the bottom surface 54a of the skid. The holder 80 is detachably attached to the drive unit 34 in a state where the holder 80 protrudes to the outside by a certain amount (step S1).

When the holder 80 is attached to the drive unit 34, the detector 30 is kept in the second rotation direction SW2 by pressing the detector 30 in the second rotation direction SW2 as indicated by reference numeral 7B in FIG. rotate an angle. At this time, the holder 80 is shaped and The mounting position is adjusted. Here, the height position A2 is known by obtaining it from the design information of the surface roughness measuring machine 18 or by actually measuring it. Therefore, the shape and attachment position of the holder 80 can be adjusted according to the height position A2.

In this manner, the tip position of the stylus 48 can be aligned with the height position A2 simply by detachably attaching the holder 80 to the drive unit 34 by the operator. Further, the detector 30 is supported by the holder 80 so that the rotation in the first rotation direction SW1 is restricted. Therefore, step S1 corresponds to the matching step of the present invention.

As shown in FIGS. 6 and 8, after completing step S1, the operator moves the robot to the operation unit 62 so that the stylus 48 of the detector 30 and the skid bottom surface 54a move toward the surface Wa to be measured. Operation input of the arm 16 is performed. In response to this operation input, the robot control unit 70 drives the robot arm 16 to move the stylus 48 and skid bottom surface 54a toward the surface Wa to be measured (step S2, corresponding to the moving step of the present invention). Also, the robot control unit 70 starts storing the teaching information 66 .

When the robot arm 16 starts to be driven, that is, when the surface roughness measuring machine 18 starts to move, the displacement detection unit 76 detects the touch based on detection signals continuously input from the detection sensor 46 via the signal processing unit 52 . The presence or absence of displacement of the needle 48 is continuously detected, and the detection results are sequentially output to the display unit 64 (step S3, corresponding to the detection step of the present invention). Accordingly, the operator can determine whether or not the tip of the stylus 48 has come into contact with the surface Wa to be measured based on the detection screen 64a displayed on the display unit 64 and visually indicating the presence or absence of displacement of the stylus 48. be possible. Then, the operator continues to manually drive the robot arm 16 until the tip of the stylus 48 contacts the surface Wa to be measured (NO in step S4).

As shown in FIGS. 6 and 9, based on the detection screen 64a displayed on the display unit 64, when the tip of the stylus 48 contacts the surface Wa to be measured, the operator moves the robot arm to the operation unit 62. 16 stop operations (including stopping the operation of the operation unit 62) are performed (YES in step S4). In response to this operation stop, the robot control unit 70 stops driving the robot arm 16 (step S5, corresponding to the stop step of the present invention). Note that steps S2 to S5 correspond to the first contact step of the present invention.

When step S5 is completed, the tip position of the stylus 48, that is, the height position A2 can be aligned with the surface Wa to be measured. Further, the robot control unit 70 causes the storage unit 60 to store the teaching information 66 corresponding to the surface Wa to be measured with which the detector 30 is brought into contact.

As indicated by symbol XA in FIGS. 6 and 10, the operator removes the holder 80 from the drive section 34 after the robot arm 16 stops driving (step S6, corresponding to the second contact step of the present invention). As a result, as indicated by symbol XB in FIG. 10 , the restriction on the rotation of the detector 30 in the first rotation direction SW1 by the holder 80 is released, so that the detector 30 is not affected by gravity or an urging member (not shown). The restoring force rotates in the first rotation direction SW1, and the skid bottom surface 54a comes into contact with the surface Wa to be measured. At this time, since the height position A2 is aligned with the surface Wa to be measured, the detector 30 is positioned at the center position A1 while the skid bottom surface 54a is in contact with the surface Wa to be measured.

Hereinafter, when there are a plurality of surfaces Wa to be measured, the processing from step S1 to step S6 is repeatedly executed for each surface Wa to be measured. remembered.

As described above, in this embodiment, by using the holder 80, the detection sensor 46, and the stylus 48, the detector 30 can be positioned at the central position A1 without relying on visual observation. As a result, the time required for teaching the robot arm 16 can be shortened, the variation in positioning accuracy of the detector 30 to the central position A1 for each operator can be reduced, and the detector 30 can be prevented from being excessively pressed against the surface Wa to be measured. It is possible to prevent damage to the surface roughness measuring device 18 due to Further, it is not necessary to provide the surface roughness measuring machine 18 with a detection switch, which is more expensive than the holder 80, in order to detect whether or not the detector 30 is at the central position A1. failure risk can be eliminated. As a result, the positioning of the detector 30 to the central position A1 can be performed with high precision and at low cost.

[Positioning method of the second embodiment]
FIG. 11 is a schematic diagram showing an example of the surface roughness measuring system 10 of the second embodiment. In the first embodiment, the operator manually positions the detector 30 at the central position A1 when the teaching information 66 is generated, but in the second embodiment, the detector 30 is automatically positioned at the central position A1. .

In the surface roughness measuring system 10 of the second embodiment, the drive unit 34 is provided with the holder 80A, the control device 20 functions as the switching control unit 79, and the robot control unit 70 and the displacement detection unit It has basically the same configuration as the surface roughness measuring system 10 of the first embodiment except that the function of 76 is partially different. For this reason, the same reference numerals are given to the same functions or configurations as those of the first embodiment, and the description thereof will be omitted.

The holder 80A constitutes the positioning device of the present invention together with the robot arm 16, the control device 20, and the detection sensor 46. As shown in FIG. The holder 80A is attached to the driving portion 34 and has a pressing portion 81 that is displaceable in the Z1-axis direction (the same direction as the Z-axis direction in the drawing). Under the control of a switching control unit 79, which will be described later, the holding member 80A is in a pressing state (FIG. 13) in which the detector 30 is pressed from below in the Z-axis direction by the pressing portion 81 and rotated in the second rotation direction SW2 by a constant angle. (see FIG. 11), and a pressed state (see FIG. 11) in which the pressing of the detector 30 by the pressing portion 81 is released. Then, when the holder 80A is switched to the pressed state, the attachment position of the holder 80A to the drive section 34 and the pressing section 81 are adjusted so that the tip position of the stylus 48 coincides with the height position A2 described above. The amount of protrusion of is adjusted.

When the teaching information 66 for each surface Wa to be measured is generated, the displacement detection unit 76 of the second embodiment detects the displacement of the stylus 48 based on the detection signals continuously input from the detection sensor 46 via the signal processing unit 52 . The presence or absence of displacement is continuously detected, and the detection results are sequentially output to the robot control section 70 .

The robot control unit 70 (corresponding to the movement control unit of the present invention) of the second embodiment, when the holder 80A is switched from the pressed state to the pressed state at the time of generating the teaching information 66, moves the surface Wa to be measured The robot arm 16 is driven according to a movement program prepared in advance to move the detector 30 (stylus 48 and skid bottom surface 54a) toward the surface Wa to be measured. The movement program is information indicating a simple measurement route from the initial position and initial attitude of the detector 30 to the surface Wa (target point) to be measured.

Further, after the robot arm 16 starts to be driven (after the surface roughness measuring device 18 starts moving), the robot control unit 70 continuously receives detection results indicating whether or not the stylus 48 is displaced from the displacement detection unit 76 . , it is determined whether or not the displacement of the stylus 48 is greater than a predetermined threshold value, that is, whether or not the tip of the stylus 48 has come into contact with the surface Wa to be measured. When the displacement of the stylus 48 is equal to or less than a predetermined threshold value, the robot control unit 70 determines that the tip of the stylus 48 is not in contact with the surface Wa to be measured, and stops the movement of the surface roughness measuring device 18. continue. When the displacement of the stylus 48 exceeds a predetermined threshold value, the robot control unit 70 determines that the tip of the stylus 48 has come into contact with the surface Wa to be measured, and stops driving the robot arm 16. Let

The switching control unit 79 controls switching between the pressed state and the released state of the holder 80A. The switching control unit 79 switches the holder 80A from the initial state of the pressure release state to the pressure state at the start of generation of the teaching information 66 of the surface Wa to be measured. The switching control unit 79 maintains the pressing state of the holder 80A while the robot arm 16 is being driven by the robot control unit 70, and presses the holder 80A when the robot control unit 70 stops driving the robot arm 16. state to the pressure released state.

[Positioning method of the second embodiment]
FIG. 12 is a flow chart showing the flow of the positioning method for positioning the detector 30 at the central position A1 when generating the teaching information 66 of the surface to be measured Wa in the second embodiment. FIG. 13 is an explanatory diagram for explaining step S1A of the flowchart shown in FIG. FIG. 14 is an explanatory diagram for explaining steps S2A and S3A of the flow chart shown in FIG. FIG. 15 is an explanatory diagram for explaining steps S4A and S5A of the flowchart shown in FIG. FIG. 16 is an explanatory diagram for explaining step S6A of the flowchart shown in FIG.

As shown in FIGS. 12 and 13, when the operator operates the operation unit 62 to start generating the teaching information 66 of the surface Wa to be measured, the switching control unit 79 switches the holder 80A from the pressure release state to the pressure state. Switch (step S1A, corresponding to the matching step of the present invention). As a result, the detector 30 is pressed by the pressing portion 81 of the holder 80A, and the detector 30 rotates in the second rotation direction SW2 by a constant angle, thereby causing the tip of the stylus 48 to rotate as in the first embodiment. The position can be matched to the height position A2. Further, in this case, the detector 30 is restricted from rotating in the first rotation direction SW1 by the pressing portion 81 .

As shown in FIGS. 12 and 14, when the holder 80A is switched to the pressing state, the robot control unit 70 drives the robot arm 16 according to the movement program corresponding to the surface Wa to be measured, and moves the detector 30 to the surface to be measured. It is moved toward the measurement plane Wa (step S2A, corresponding to the movement step of the present invention). Also, the robot control unit 70 starts storing the teaching information 66 .

When the robot arm 16 starts to be driven, that is, when the surface roughness measuring machine 18 starts to move, the displacement detection unit 76 detects the touch based on detection signals continuously input from the detection sensor 46 via the signal processing unit 52 . The presence or absence of displacement of the needle 48 is continuously detected, and the detection results are sequentially output to the robot control unit 70 (step S3A, corresponding to the detection step of the present invention). Thereby, the robot control section 70 can determine whether or not the tip of the stylus 48 has come into contact with the surface Wa to be measured. When determining that the tip of the stylus 48 is not in contact with the surface Wa to be measured, the robot control unit 70 continues driving the robot arm 16 (NO in step S4A).

On the other hand, as shown in FIGS. 12 and 15, based on the detection results sequentially input from the displacement detection unit 76, the robot control unit 70 determines that the tip of the stylus 48 has come into contact with the surface Wa to be measured. stops driving the robot arm 16 (YES in step S4A, step S5A, which corresponds to the stop step of the present invention). Note that steps S2A to S5A correspond to the first contact step of the present invention. As a result, the tip position of the stylus 48, that is, the height position A2 can be aligned with the surface Wa to be measured, as in the first embodiment. Further, the robot control unit 70 causes the storage unit 60 to store teaching information 66 corresponding to the surface Wa to be measured.

As shown in FIGS. 12 and 16, when the driving of the robot arm 16 stops, the switching control unit 79 switches the holder 80A from the pressed state to the released state (step S6A, corresponding to the second contact step of the present invention). . As a result, the rotation restriction of the detector 30 in the first rotation direction SW1 by the holder 80A is released, so that the detector 30 rotates in the first rotation direction SW1 as in the first embodiment, and the skid bottom surface 54a is It comes into contact with the surface Wa to be measured. As a result, the detector 30 is positioned at the central position A1 while the skid bottom surface 54a is in contact with the surface Wa to be measured.

Hereinafter, when there are a plurality of surfaces Wa to be measured, the processing from step S1A to step S6A is repeatedly executed for each surface Wa to be measured. remembered.

As described above, in the second embodiment, the positioning of the detector 30 to the central position A1 can be automatically executed. As a result, this positioning can be completed in a shorter time than in the first embodiment. In addition, variations in positioning accuracy of the detector 30 to the central position A1 can be reduced more than in the first embodiment.

[others]
In each of the above embodiments, the robot arm 16 holding the surface roughness measuring instrument 18 brings the stylus 48 of the detector 30 and the skid bottom surface 54a into contact with the surface Wa to be measured. and the skid bottom surface 54a) and the surface to be measured Wa (stage 12) may be used to move one of them toward the other. Also, instead of using a robot, various known moving mechanisms (actuators) capable of moving either the detector 30 or the surface to be measured Wa toward the other may be used.

In each of the above-described embodiments, the positioning of the detector 30 of the surface roughness measuring machine 18 for measuring the surface roughness of the surface Wa to be measured has been described as an example. The present invention is applicable to detector positioning of various surface profilometers having stylus 48 and skid 54, such as contour profilometers that measure . When the surface Wa to be measured is limited to a horizontal plane (including a substantially horizontal plane), the stylus 42 is biased in the first rotation direction SW1 by utilizing the weight of the stylus 48 and the tip of the slicer 42b. Alternatively, the biasing member 44 may be omitted in this case.

10 Measurement system 12 Stage 14 Robot base 16 Robot arms 16a1 to 16a5 Arm 16b Joint 16c End effector 16d Adapter 18 Measuring device 20 Control device 30 Detector 30a Housing 32 Nosepiece 34 Driving unit 40 Swing fulcrum 42 Stylus 42a Stylus body Part 42b Stylus distal end 42c Stylus proximal end 44 Biasing member 46 Detection sensor 46a Core 46b Coil 48 Stylus 50 Signal cable 52 Signal processing part 54 Skid 54a Skid bottom surface 54b Stylus insertion hole 60 Storage part 62 Operation part 64 Display part 64a Detection screen 66 Teaching information 70 Robot control unit 72 Measuring instrument control unit 74 Movement amount detection unit 76 Displacement detection unit 78 Surface shape analysis unit 79 Switching control unit 80 Holding tool 80A Holding tool 81 Pressing part A1 Center position A2 Height position R Swing range SW1 First rotation direction SW2 Second rotation direction W Workpiece Wa Surface to be measured

Claims (6)

a skid having a bottom surface in contact with a surface to be measured and a through hole opening in the bottom surface; a stylus supported so as to be swingable around a swing fulcrum; a stylus provided at a tip portion of the stylus that moves away from the skid when it approaches and rotates in a second rotation direction opposite to the first rotation direction, and is inserted into the through hole; a detector comprising a biasing member that biases in a rotational direction;
a drive unit that holds the detector so as to be swingable in the first rotation direction and the second rotation direction and that moves the detector in a driving direction perpendicular to the axial direction of the swing fulcrum;
In a surface profilometer comprising
A positioning method for positioning the detector at the center position of the swing range of the detector when the skid is brought into contact with the surface to be measured,
By rotating the detector in the second rotation direction, the position of the tip of the stylus protruding from the bottom surface due to the biasing of the biasing member is adjusted to the height of the bottom surface when the detector is at the center position. a matching step to match the position
A first contact step of moving the detector relative to the surface to be measured to bring the tip of the stylus into contact with the surface to be measured while the tip position of the stylus is aligned with the height position. When,
a second contact step of rotating the detector in the first rotation direction to bring the bottom surface into contact with the surface to be measured after the completion of the first contact step;
positioning method. The first contacting step includes:
a moving step of moving one of the tip of the stylus and the surface to be measured toward the other by relatively moving the detector with respect to the surface to be measured;
a detecting step of continuously detecting whether or not the stylus is displaced while the moving step is being performed;
a stopping step of stopping the moving step when displacement of the stylus is detected in the detecting step;
The positioning method of claim 1, comprising: 3. The moving step according to claim 2, wherein a robot capable of holding the surface shape measuring machine and changing the position and orientation of the surface shape measuring machine is controlled to move the detector toward the surface to be measured. positioning method. In the matching step, a holder is detachably attached to the drive unit, and the holder presses the detector to rotate it in the second rotation direction by a predetermined angle, thereby moving the tip position of the stylus to the height. and the holder restricts the rotation of the detector in the first rotation direction,
4. The detector according to any one of claims 1 to 3, wherein, in the second contact step, the detector is rotated in the first rotation direction by removing the holder from the drive unit to release the rotation regulation. positioning method. a skid having a bottom surface in contact with a surface to be measured and a through hole opening in the bottom surface; a stylus supported so as to be swingable around a swing fulcrum; a stylus provided at a tip portion of the stylus that moves away from the skid when it approaches and rotates in a second rotation direction opposite to the first rotation direction, and is inserted into the through hole; a detector comprising a biasing member that biases in a rotational direction;
a drive unit that holds the detector so as to be swingable in the first rotation direction and the second rotation direction and that moves the detector in a driving direction perpendicular to the axial direction of the swing fulcrum;
In a surface profilometer comprising
A positioning device that positions the detector at the center position of the swing range of the detector when the skid is brought into contact with the surface to be measured,
A holding fixture attached to the drive unit, which is switchable between a pressed state in which the detector is pressed and rotated in the second rotation direction, and a pressed state in which the detector is released from the pressed state. a holder;
a relative movement unit that relatively moves the detector with respect to the surface to be measured;
a switching control unit that controls switching between the pressing state and the pressing release state of the holder;
A movement control unit that drives one of the tip of the stylus and the surface to be measured toward the other by driving the relative movement unit when the holder is switched to the pressed state by the switching control unit. When,
a displacement detection unit that continuously detects whether or not the stylus is displaced while the relative movement unit is being driven;
with
The holder in the pressed state causes the position of the tip of the stylus projected from the bottom surface by the biasing of the biasing member to coincide with the height position of the bottom surface when the detector is at the center position. ,
The movement control unit stops driving the relative movement unit when the displacement detection unit detects displacement of the stylus,
When the movement control unit stops driving the relative movement unit, the switching control unit switches the holder from the pressing state to the pressing release state, thereby moving the detector in the first rotation direction. and rotates the positioning device to bring the bottom surface into contact with the surface to be measured. 6. The positioning apparatus according to claim 5, wherein the relative movement unit is a robot that holds the surface profile measuring machine and can change the position and orientation of the surface profile measuring machine.

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