JPH0736009U - Work shape automatic detection device - Google Patents

Abstract

(57) [Summary] [Purpose] It is an object to provide a work shape automatic detection device capable of automatically detecting the outer peripheral shape of a work having an arbitrary shape. According to an aspect of the present invention, there is provided a work shape automatic detection device which detects a detection tool from a contact position in contact with a work along a direction orthogonal to a tangent line of a work including the detection tool.
Is retracted by a predetermined distance and is rotated by 90 degrees in a predetermined direction with respect to the retracting direction, and is moved by a second predetermined distance along a lateral direction, and is rotated by 90 degrees in the predetermined direction with respect to the lateral direction. While moving along the approach direction until contact with the work is detected, this operation is repeatedly controlled, and the detected contact position is stored in the storage unit every time the contact position is detected, and the entire work is detected. Based on the contact position detected over the circumference, the outer peripheral shape of the workpiece is detected, the contact portion of the detection tool is formed into a substantially spherical shape, and the diameter of this contact portion is set to be larger than the second predetermined distance. Is characterized by.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a work shape automatic detection device capable of automatically detecting the shape of a work having an arbitrary shape.

[0002]

[Prior art]

 Conventionally, for example, when a processing robot, which is an automatic processing apparatus, attempts to deburr or chamfer the outer peripheral edge of a work of an arbitrary shape, first, the outer shape of the work of this arbitrary shape is manually processed by an operator. In the work, the outer circumference of the work is traced via a teaching jig to teach the outer circumference to the machining robot, or the outer shape of the work is input numerically by key input operation by the operator.

[0003]

[Problems to be solved by the device]

 However, the work of making the robot remember the outer peripheral shape of such an arbitrarily shaped work eventually depends on human manual work, which is time-consuming and requires a teaching operation by an operator or a numerical input by an operator. There was a demand for a system that can detect the shape of the workpiece automatically because of variations in movement.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a work shape automatic detection device capable of automatically detecting the outer peripheral shape of a work having an arbitrary shape. is there.

[0005]

[Means for solving the problem]

 In order to solve the above-mentioned problems and achieve the object, the work shape automatic detection device according to the present invention is, according to the description of claim 1, provided with a base and having conductivity. A work chucking means for detachably gripping and fixing a work, a contact part formed in a substantially spherical shape, and a conductive detection tool, and a tool holding tool for holding the detection tool in an electrically insulated state Means, a driving means for two-dimensionally moving and driving the tool holding means in a plane parallel to the base, and the detection tool and at least the work are electrically connected to each other, and a power source and a resistance are provided. And an electric circuit means connected to the electric circuit means for detecting the electric potential of the electric circuit means, and the electric potential detection means contacting the detection tool with the work to cause the electric The potential of the circuit means has dropped A position detecting means for two-dimensionally detecting a contact position between the detection tool and the workpiece at the time when a thing is detected; a storage means for storing contact position information detected by the position detecting means; The detection tool is retracted by a first predetermined distance along a retreat direction away from a predetermined contact position detected by the position detection means, and after this retreat operation, a first tool is moved along a lateral direction intersecting the retreat direction. After moving for a predetermined distance of 2, the lateral movement operation is continued until the contact position is detected by the position detecting means along the approaching direction approaching the work, and the driving is performed so as to repeat this operation. When the contact position is detected, the contact position is stored in the storage unit each time the contact position is detected, and the outer peripheral shape of the work is determined based on the contact position detected over the entire circumference of the work. To And a diameter of a substantially spherical contact portion of the detection tool is set to be larger than a distance on the surface of the work corresponding to the second predetermined distance. .

According to a second aspect of the present invention, there is provided a work shape automatic detection device, wherein a base and a work which is disposed on the base and has conductivity is detachably held. The workpiece chuck means for fixing, the contact part formed in a substantially spherical shape, and the conductive detection tool, the tool holding means for holding the detection tool in an electrically insulated state, and the tool holding means Drive means for two-dimensionally moving and driving in a plane parallel to the base, and electric circuit means for electrically connecting the detection tool and at least the work and having a power source and a resistor, An electric potential detecting means connected to the electric circuit means for detecting the electric potential of the electric circuit means, and the electric potential detecting means detects that the electric potential of the electric circuit means is lowered due to the contact between the detection tool and the work. At the time Position detecting means for two-dimensionally detecting the contact position between the detection tool and the workpiece, storage means for storing contact position information detected by the position detecting means, and the detection tool Only a first predetermined distance is evacuated along the evacuation direction away from the predetermined contact position detected by the detection means, and after this evacuation operation, only a second predetermined distance along the lateral direction intersecting the evacuation direction. After this horizontal movement operation, the movement means is moved along the approaching direction approaching the work until the contact position is detected by the position detection means, and the driving means is controlled to repeat this operation, Each time the contact position is detected, the detected contact position is stored in the storage unit, and the outer peripheral shape of the workpiece is detected based on the contact position detected over the entire circumference of the work. And However, the second predetermined distance set by the control means is set within a range in which the corresponding distance on the work surface is smaller than the diameter of the substantially spherical contact portion of the detection tool. It has a feature.

According to a third aspect of the present invention, there is provided a work shape automatic detection device, wherein a base and a work which is disposed on the base and has conductivity is detachably held. The workpiece chuck means for fixing, the contact part formed in a substantially spherical shape, and the conductive detection tool, the tool holding means for holding the detection tool in an electrically insulated state, and the tool holding means Drive means for two-dimensionally moving and driving in a plane parallel to the base, and electric circuit means for electrically connecting the detection tool and at least the work and having a power source and a resistor, An electric potential detecting means connected to the electric circuit means for detecting the electric potential of the electric circuit means, and the electric potential detecting means detects that the electric potential of the electric circuit means is lowered due to the contact between the detection tool and the work. At the time Position detecting means for two-dimensionally detecting the contact position between the detection tool and the workpiece, storage means for storing contact position information detected by the position detecting means, and the detection tool A predetermined predetermined distance is evacuated from the predetermined contact position detected by the detection means along a retreat direction that separates in a state orthogonal to the close battle at the contact position, and after this retreat operation, the retreat direction is orthogonal to this retreat direction. After moving for a second predetermined distance along the lateral direction, after this lateral movement operation, the contact position is detected by the position detecting means along the approaching direction that approaches the workpiece in a state orthogonal to the lateral direction. The driving means is controlled so as to repeat this operation until the contact position is detected, and the detected contact position is stored in the storage means every time the contact position is detected. Detected And a control means for detecting the outer peripheral shape of the workpiece based on the contact position, and the diameter of the contact portion of the detection tool having a substantially spherical shape is on the surface of the workpiece corresponding to the second predetermined distance. It is characterized by being set larger than the distance in.

According to a fourth aspect of the present invention, there is provided a work shape automatic detection device, a base and a work provided on the base, which has a conductive work and is detachably gripped. Which is provided with a workpiece chuck means to be fixed, a contact part formed in a substantially spherical shape, and a conductive detection tool, a tool holding means for holding the detection tool in an electrically insulated state, and the tool holding means. Drive means for two-dimensionally moving and driving in a plane parallel to the base, and electric circuit means for electrically connecting the detection tool and at least the work, and having a power supply and a resistor. There is a possibility that the electric potential of the electric circuit means is lowered due to the electric potential detecting means connected to the electric circuit means and detecting the electric potential of the electric circuit means, and the electric potential detecting means coming into contact with the detection tool and the workpiece. At the time of detection Position detection means for two-dimensionally detecting the contact position between the detection tool and the workpiece, storage means for storing contact position information detected by the position detection means, and the detection tool for detecting the position. A predetermined predetermined distance is evacuated from the predetermined contact position detected by the means along a retreat direction that is separated in a state orthogonal to the close battle at the contact position, and after this retreat operation, the retreat direction is orthogonal to this retreat direction. The contact position is detected by the position detecting means along the approach direction in which the workpiece is approached in a state orthogonal to the lateral direction after the lateral movement operation by a second predetermined distance. The driving means is controlled so as to repeat this operation while being moved until the contact position is detected, and the detected contact position is stored in the storage means every time the contact position is detected. Crossing detected Control means for detecting the outer peripheral shape of the workpiece based on the contact position, and the second predetermined distance set by the control means is smaller than the diameter of the substantially spherical contact portion of the detection tool. It is characterized by being set within a range.

[0009]

【Example】

 The configuration of one embodiment of the work shape automatic detection device according to the present invention will be described below with reference to the accompanying drawings.

First, referring to FIGS. 1 and 2, the structure of the workpiece shape automatic detection device 10 of this embodiment will be described. As shown in FIG. 1, the work shape automatic detection device 10 is provided with a flat rectangular device body 12, and a rectangular opening 14 similar to the outer shape of the device body 12 is formed on the upper surface of the device body 12. Has been done. The bottom surface of the opening 14 is defined from the upper surface of a base 16 having conductivity, and an arbitrary shape (ellipsoidal shape in this embodiment) having conductivity is provided on the base 16. A work chuck 18 for holding W in a detachably fixed state is provided as work chuck means. Although not shown in detail, the work chuck 18 is configured to chuck the work W through electromagnetic force in this embodiment.

In this embodiment, the work chuck 18 is constructed so as to be electrically conductive as a whole. The base 16 and the work chuck 18 are electrically connected to each other. As a result, the base 16, the work chuck 18, and the work W gripped by the work chuck 18 always have the same potential.

On the other hand, on the apparatus main body 12, a holder 20 as a tool holding means is arranged so as to be freely movable two-dimensionally within a plane set parallel to the base 16. The holder 20 is movably driven along a two-dimensionally free direction in the above-mentioned plane via a holder driving mechanism 22 as a driving means. A probe 24 as a detection tool for detecting the outer peripheral shape of the work W is attached to the holder 20 via an electric insulating member 26. That is, the probe 24 is attached to the holder 20 while being electrically insulated from the holder 20.

The probe 24 is made of a conductive material as a whole, and is attached to the holder 20 substantially vertically so that the upper end and the lower end thereof are projected from the upper surface and the lower surface of the holder 20, respectively. And a detection sphere 24b having a predetermined diameter D and integrally joined from the lower end of the probe body 24a. The probe 24 is attached to the holder 20 with its vertical position adjusted so that the detection ball 24b can contact the outer peripheral end surface of the work W.

The holder drive mechanism 22 described above extends along the y-axis direction in the drawing and is movably arranged along the x-axis direction, so that the holder 20 described above can move along the y-axis direction. The supported x-axis arm 28, the x-axis direction drive mechanism 30 for moving and driving the x-axis arm 28 along the x-axis direction, and the holder 20 described above on the x-axis arm 28 along the y-axis direction. And a y-axis direction drive mechanism 32 for moving and driving the motor.

Here, the x-axis direction drive mechanism 30 has long grooves 34 a formed on the upper end surfaces 12 a and 12 b of the apparatus main body 12 arranged in parallel with each other so as to extend along the x-axis direction. , 34b, a pair of x-axis ball screws 36a, 36b that are respectively disposed in the long grooves 34a, 34b and extend along the x-axis direction, and these x-axis ball screws 36a, 36b are in synchronization with each other. An x-axis servomotor 38 (shown in FIG. 2) for reversible rotation driving is provided. At both ends of the x-axis arm 28, fitting portions 28a and 28b which are respectively fitted into the long grooves 34a and 34b are integrally formed. These x-axis ball screws 36a and 36b are fitted into these fitting portions 28a. , 28b are respectively screwed into ball nuts 40a, 40b formed respectively. Since the x-axis direction drive mechanism 30 is configured in this way, the x-axis arm 28 moves along the x-axis direction by activating the x-axis servomotor 38 in either the forward or reverse direction. It will be driven.

Further, the y-axis direction drive mechanism 32 is provided with a long groove 42 formed on the upper surface of the x-axis arm 28 so as to extend along the y-axis direction, and is arranged in the long groove 42. A y-axis ball screw 44 extending along the direction and a y-axis servomotor 46 (shown in FIG. 2) for reversibly rotating the y-axis ball screw 44 are provided. A fitting portion 20a fitted into the long groove 40 is integrally formed at one end of the holder 20, and the y-axis ball screw 42 is screwed into a ball nut 48 formed in the fitting portion 20a. ing.

Since the y-axis direction drive mechanism 32 is configured as described above, the holder 20 is moved along the y-axis direction by activating the y-axis servomotor 46 in either the forward or reverse direction. It will be driven to move.

Here, as shown in FIG. 2, a control unit 50 is connected to both the y-axis servo motor 38 of the x-axis direction drive mechanism 30 and the y-axis servo motor 46 of the y-axis direction drive mechanism 32. It is designed to be driven under the control of the control unit 50. As a result, the probe 24 held by the holder 20 is driven to move along a two-dimensional free direction within a plane set parallel to the upper surface of the base 16 under the control of the control unit 50. Will be able to be done. The control procedure in the control unit 50 will be described later in detail with reference to the flowchart.

The x-axis direction drive mechanism 30 and the y-axis direction drive mechanism 32 immediately receive the motor shaft of the x-axis servomotor 38 when a stop signal is input from the control unit 46. To stop the rotation of the motor shaft of the y-axis servo motor 46, and to stop the movement drive of the probe 24 in the x-axis direction and the y-axis direction, respectively.

On the other hand, x-axis and y-axis rotary encoders 52 and 54 (shown in FIG. 2) as position detecting means are respectively provided on the motor axes of the above-mentioned x-axis servo motor 38 and y-axis servo motor 46, respectively. They are connected and are configured so that the rotation amounts of the corresponding servo motors 38 and 46 can be accurately detected. These rotary encoders 52 and 54 are connected to the control unit 50. The control unit 50 uses the output information from the rotary encoders 52 and 54 to detect the current position P (that is, x) of the detection ball 24b (that is, the tip position that contacts the work W) of the probe 24 held by the holder 20. The position in the axial direction and the position in the y-axis direction are accurately detected, and the x-axis direction drive mechanism 30 and the y-axis direction drive mechanism 32 are driven and controlled based on the detection information.

Here, in this embodiment, in order to detect the current position P of the probe 24 held by the holder 20, rotary encoders 52, attached to the motor shafts of the servomotors 38, 46, respectively, However, the present invention is not limited to such a configuration, and the linear encoders are provided along the moving range of the x-axis arm 28 and the moving range of the holder 20, respectively. , The current position P of the x-axis arm 28 and the holder 20 may be detected.

On the other hand, the probe 24 and the base 16 (therefore, the work chuck 18 electrically connected to the base 16 and the work W held in the state of being electrically connected to the work chuck 18) The two are electrically connected by an electric circuit 56 as electric circuit means. The electric circuit 56 is provided with an electric wiring 56a for electrically connecting the probe 24 and the base 16, to which a DC power source 56b of 5V and a resistor 56c having a predetermined resistance value are connected in series. It is connected. By configuring the electric circuit 56 as described above, when the probe 24 is not in contact with the work W, the electric circuit 56 is in an open (cut) state. Therefore, the voltage of the electric wiring 56a is equal to the power source. A predetermined voltage defined by 56b will appear. On the other hand, when the probe 24 contacts the work W, the electric circuit 56 is closed, and a current flows through the electric wiring 56a, so that the voltage becomes substantially "0".

That is, in the present invention, whether or not the probe 24 contacts the work W in this way is determined by whether or not the voltage of the electric circuit 56 is “0”, and the voltage of the electric circuit 56 is a predetermined value. It is used to detect that the probe 24 is in contact with the work W at the time point when the state of exhibiting “0” is changed to “0”.

To the electric circuit 56, a detection circuit 58 as a potential detecting means is connected to the electric wiring 56a in order to detect a voltage appearing in the electric circuit 56 and detect a contact state of the probe 24 with the work W. There is. The detection circuit 58 has one end connected to the electric wiring 56a, the other end grounded, and emits light when the probe 24 is not in contact with the work W, and disappears as the probe 24 contacts the work W. A photodiode (LED) 60 and a phototransistor 62 that is turned on by receiving light from the photodiode 60 are provided, and the photodiode 60 and the phototransistor 62 form a photocoupler 64. Incidentally, one end of this phototransistor 62 is grounded, and the other end is connected to the control unit 50 as a detection end. The phototransistor 62 is configured to output to the control unit 50 an "L" level signal while the photodiode 60 is emitting light and an "H" level signal while the photodiode 60 is extinguished. ing.

The control unit 50 determines that the probe 24 is not in contact with the work W while the “L” level signal is input from the detection circuit 58, and the “L” level signal is detected. When the input state changes from the "H" level signal to the "H" level signal, it is determined that the probe 24 has contacted the work W.

The control procedure of the automatic shape detection of the work W based on the detected contact position in the control unit 50 will be described later in detail with reference to the flowcharts shown in FIGS. 3 to 5. As described above, when the input signal from the detection circuit 58 changes from the “L” level to the “H” level, it is determined from the rotary encoders 52 and 54 that the probe 24 contacts the work W. Based on the detection information of P, the contact position information P of the probe 24 to the work W, that is, the x-axis direction position and the y-axis direction position at the center position C of the detection ball 24b of the probe 24 is used as the detection information, The storage unit 66 is connected to the unit 50 and serves as a storage unit. In this embodiment, the detection sphere 24b is formed with a predetermined diameter D. Therefore, the center position C of the detection sphere 24b and the contact position with the work W actually differ, but in this embodiment, the control unit 50 controls the detection sphere 24b of the probe 24. The center position C is set to be stored as a contact position.

Further, an input section 68 is connected to the control unit 50, and information necessary for automatic detection, for example, the shape of one work, is input via a keyboard (not shown) constituting the input section 68. The initial approach direction, the return movement amount (L ₁ ), the lateral movement amount (L ₂ ) and the like at the time of detection are input. A display unit 70 is connected to the control unit 50, and a detection result, that is, the outer shape of the detected work W and its detection data are displayed on a CRT (not shown) that constitutes the display unit 70. It is configured like. In this embodiment, the lateral movement amount (L ₂ ) described above is set to be smaller than the diameter D of the detection sphere 24b of the probe 24. In other words, the control unit 50 is configured so as not to accept the setting of the lateral movement amount larger than the diameter D of the detection sphere 24b.

Here, the longer the return movement amount L ₁ is set, the more reliably the shape change of the work W can be followed, but if it is too long, the detection operation time will be long. Therefore, the workability is deteriorated. Therefore, for example, in this embodiment, L ₁ is set to 5 mm. Further, the shorter the lateral movement amount L ₂ is set, the higher the shape detection accuracy of the workpiece becomes, but if it is too short, the detection operation time becomes long, and similarly, the workability is deteriorated. become. Therefore, in this embodiment, L ₂ is set to 1.0 mm, for example. It should be noted that the number of measurements N to be performed per one circumference of the work W varies depending on the outer shape of the work W even if L ₂ is set in advance, and it is meaningless to set this in advance. .

The value input via the input unit 68 is stored in the storage unit 66. Although not shown, the input section 68 is provided with various operation switches such as a detection operation start switch and an emergency stop switch.

The work shape automatic detection operation of the control unit 50 in the work shape automatic detection apparatus 10 configured as described above will be described with reference to FIGS. 3 to 7.

That is, in the work shape automatic detection operation of this embodiment, first, the work W is chucked on the work chuck 18. In this chuck operation, the predetermined part of the work W is set so as to be accurately brought to the detection operation start position, that is, the position facing the probe 24 at the initial setting position. Here, the work W is formed to have a uniform thickness in this embodiment.

After the work W is chucked on the work chuck 16 in this manner, the initial approach direction is input via the input unit 68. Here, the initial approach direction is set so that the probe 24 first comes into contact with the above-mentioned predetermined portion of the work W. The initial approach direction thus set / input is temporarily stored in the storage unit 66. After that, the detection operation start switch (not shown) is turned on to start the automatic detection operation of the outer shape of the work W.

That is, as shown in FIG. 3, when this automatic detection operation is activated, the control unit 50 executes an initialization operation (S10). In this initialization operation, the probe 24 is moved to the initial setting position, the memory information of the contact position P _N in the storage unit 66 is erased, and the detection number N is set to 0. After that, the first approach (approach) direction once stored in the storage unit 66 is read (S12). Here, although it is not described as a control procedure, if it is found that the initial approach direction is not stored in the storage unit 66, an alarm sound is generated via an alarm device (not shown), and the display is displayed. A message prompting the input of the first approach direction is displayed on the section 70. Then, wait for the input of the first approach direction and proceed to the next step.

In step S12, when the first approach direction is read, the holder drive mechanism 22, that is, the x-axis direction drive mechanism 30 and the holder drive mechanism 22 are moved so that the probe 24 moves forward along the read first approach direction. The y-axis direction drive mechanism 32 is drive-controlled (S14). This forward movement is continued until the probe 24 comes into contact with the work W and the output level of the detection signal from the detection circuit 58 changes from "L" to "H" in step S16, and the output level is " When the probe 24 comes into contact with the work W at the time of changing from “L” to “H”, the forward drive operation of the probe 24 by the holder drive mechanism 22 is stopped as shown in step S18.

That is, in this embodiment, the detection circuit 58 detects that the probe 24 “contacts” the work W based on the change in the potential of the electric circuit 56 based on this “contact”. Therefore, when the probe 24 and the work W are electrically connected, this "contact" is detected. As a result, compared with the case where contact is detected via a piezoelectric element or limit switch, etc., the holder is driven in the state of contact with substantially no contact pressure (or contact pressure that is negligible). The forward drive operation of the mechanism 22 can be stopped. Therefore, according to this embodiment, the detection point on the work W based on the "contact position" P _N , that is, the center position C _N of the detection ball 24b can be detected very accurately.

Then, the x-axis direction position information and the y-axis direction position information at the center position C of the detection sphere 24b of the probe 24 at this stop position are read, and these read x-axis direction position information and y-axis direction position information are read. Based on the above, the contact position P _N of the probe 24 to the work W is calculated (S20). In this embodiment, the contact position P _N is defined as a position deviated from the center position C of the detection sphere 24b by the radius (2 / D) of the detection sphere 24b along the approach direction. The contact position P _N (that is, P ₀ ) based on the thus calculated center position C is used as x-axis position information and y-axis direction information at the center position C of the detection ball 24b of the probe 24 at the stop position described above. It is stored in the storage unit 66 together with the position information (S22). By executing the steps up to this point, the contact position P ₀ of the detection ball 24b of the probe 24 moved along the first approach direction to the work W and the center position C ₀ of the detection ball 24b are stored in the storage unit 66. Will be done.

After that, the return (retraction) operation of the probe 24 is executed. In this return direction, the return from the first detection point P ₀ and the detection points after the first detection (P ₁ to ) Is set differently when returning from. Therefore, before executing the return operation, it is determined whether or not the number of detection times N is 0 in order to predefine the return direction (S24). Here, when it is determined that N = 0, that is, when the return operation returns from the first detection point P ₀ , the return direction is set to the opposite direction to the first approach direction (S2). 6). On the other hand, when it is determined that N = 0, that is, when the return operation returns from the contact position (P _1- ) after the first time, the return direction is set to the previous contact position P. _It is set in the direction orthogonal to the line segment A _N connecting _N-1 and the current contact position P _N (S28).

After step S22, since N = 0, the return direction is set to the opposite direction to the initial approach direction. After setting the return direction in this way, the holder drive mechanism 22 is driven so that the probe 24 returns by a predetermined return amount L ₁ along the return direction set opposite to the initial approach direction. .

After the return movement by the movement amount L ₁ is completed, it is determined whether or not the detection operation over the entire circumference of the work W is completed (S 32). Here, this end determination is set to be made at the time when it is determined that the contact position P _N has exceeded the initial contact position P ₀ . Here yet. When it is determined that the detection operation over the entire circumference of the work W is not completed, the detection number N is incremented by "1" (S34) as shown in FIG. That is, the holder driving mechanism 22 is driven so that the probe 24 moves by a predetermined lateral movement amount L ₂ along the direction rotated clockwise by 90 degrees (S36).

After the lateral movement of the moving amount L ₂ is completed, the probe 24 is moved forward so as to move further to the right, that is, along the direction rotated by 90 degrees clockwise. The rudder drive mechanism 22 is driven (S38). This forward movement is continued until the probe 24 contacts the work W and the output level of the detection signal from the detection circuit 58 changes from "L" to "H" in step S40, and the output level is " When the probe 24 contacts the work W at the time of changing from "L" to "H", the forward drive operation of the probe 24 by the holder drive mechanism 22 is stopped as shown in step S42.

Then, the x-axis direction position information and the y-axis direction position information of the detection ball 24b of the probe 24 at this stop position are read, and the probe 24 of the probe 24 is read based on the read x-axis direction position information and y-axis direction position information. The contact position P _N to the work W is calculated (S44), and the center position C of the detection sphere 24b thus detected and the contact position P _N (that is, P ₀ ) based on this center position C are stored in the storage unit. It is stored in 66 (S46). By executing the steps up to this point, the contact position P ₁ based on the contact position of the probe 24 with the work W by the second forward movement (N = 1) is stored in the storage unit 66.

Thereafter, a line segment A _N connecting the presently detected contact position P _N and the previously detected contact position P _N-1 is calculated (S48). After that, the process returns to step S24 described above, and it is determined whether or not the number of times of detection N is 0. Here, since the detection number N has already been incremented by "1" in step S34, the return direction is the line segment A _N calculated in step S48 described above (that is, the previous contact position P _N-1 and It is set in the direction orthogonal to the line segment A _N that connects the contact position P _N this time.

After that, the steps S24 to S48 are repeatedly executed, so that the center position of the detection sphere 24b is C ₂ , C ₂ , C ₄ , C ₅ , C _6, ... As shown in FIG. it sought, also, the contact position will be determined to _{P 2, P 3, P 4} , P 5, P 6 ......, these position information, it that will be sequentially stored in the storage unit 66 in step S46 become.

Here, when it is determined in step S32 that the detection operation over the entire circumference of the work W is completed, as shown in FIG. 5, all the center positions C of the detection spheres 24b detected from the storage unit 66 are detected. The position information C _N of the contact position is read out (S50), and based on all the position information C _N of the read center position C of the detection sphere 24b, a line segment sequentially connecting the contact positions in an envelope is calculated. The outer peripheral shape of the work W is calculated from the shape that is inside the calculated envelope by the radius of the detection sphere 24b (S52). Then, the outer peripheral shape of the work W thus obtained by the calculation is displayed on the display unit 70 (S54), and the calculation result is stored in the storage unit 66 (S56). In this way, the control procedure for a series of detection operations is completed.

In this way, in this embodiment, the operation of detecting the outer peripheral shape of the work W is automatically and highly accurately performed by executing the operation of automatically detecting the work shape. You can do it.

In particular, in this embodiment, the lateral movement amount (L ₂ ) of the probe 24 is smaller than the diameter (D) of the detection sphere 24b of the probe 24, in other words, the detection sphere 24b of the probe 24. The diameter (D) is set to be larger than the lateral movement amount (L ₂ ) of the probe 24. As a result, as shown in FIG. 7, even if the detection surface of the workpiece W has a corner that bends at about 90 degrees, the detection ball must be located at the apex of this corner in the above-described approach operation. The outer peripheral surface of 24b comes into contact. That is, in the state where the outer peripheral surface of the detection sphere 24b is in contact with the apex of the corner in this way, the contact position P _{3 of} this contact position P ₃ is further forward than the previous contact position P ₂ along the approach direction. Will be defined as. Therefore, the next approaching direction will always come into contact with the other surface constituting this corner, even though it is inclined by a predetermined angle. In this way, according to this embodiment, even if the work W has a corner that bends at approximately 90 degrees, this corner can be reliably detected.

Needless to say, the present invention is not limited to the configuration and method of the above-described embodiment, and can be variously modified without departing from the scope of the present invention.

Further, in the above-described embodiment, the lateral movement direction after the return operation by the predetermined distance L ₁ is described as being the right direction of the return direction, but the present invention has such a configuration. For example, it may be set to the left of the return direction without limitation. However, when the lateral movement direction is set to the left of the return direction, the subsequent changing direction of the movement direction is also the left direction. This is because unless the above setting is made, it is impossible to approach the work W due to this direction change.

In addition, in the above-described embodiment, the holder moving mechanism 22 is configured by the x-axis direction driving mechanism 30 and the y-axis direction moving mechanism 32, and it is described that the orthogonal coordinate system is used. However, the present invention is not limited to such a configuration, and may have a configuration including two rotary arms using a cylindrical coordinate system. In short, any driving form may be used as long as the probe 24 can freely move in a plane.

Further, in the above-described embodiment, the retracting direction of the probe 24 is determined from the contact position with the outer peripheral surface of the work W from the direction orthogonal to the tangent line of the work W including the probe W. The lateral direction of 24 is defined from the direction rotated 90 degrees in a predetermined direction with respect to the retracting direction, and the approach direction of the probe 24 is a direction rotated 90 degrees in the predetermined direction with respect to the lateral direction. However, the present invention is not limited to such an angle setting and can be moved at any angle.

Further, in the above-described embodiment, the retracting direction after the probe 24 contacts the work W is orthogonal to the line segment connecting the previous contact position P _{N -1} and the current contact position P _N. However, the present invention is not limited to such a configuration. For example, the retracting direction after the probe 24 comes into contact with the work W is set to the previous center position C _{N. It} goes without saying that it may be specified from the direction orthogonal to the line segment connecting _-1 and the current center position C _N.

[0052]

[Effect of device]

 As described above in detail, therefore, according to the present invention, there is provided a work shape automatic detection device capable of automatically detecting the outer peripheral shape of a work having an arbitrary shape.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a configuration of an embodiment of a work shape automatic detection device according to the present invention.

FIG. 2 is a block diagram showing an entire system of the work shape automatic detection device shown in FIG.

[Fig. 3]

[Fig. 4]

5 is a flowchart showing a control procedure of a work shape automatic detection method in a control unit in the work shape automatic detection apparatus shown in FIG.

FIG. 6 is a diagram showing a detection locus of a probe when automatically detecting the outer shape of a work of arbitrary shape according to the control procedure shown in FIGS. 3 to 5;

FIG. 7 is a diagram showing a probe detection locus when automatically detecting a work shape having a corner bent at approximately 90 degrees according to the control procedure shown in FIGS. 3 to 5;

[Explanation of symbols]

 10 Work Shape Automatic Detection Device 12 Device Main Body 12a; 12b Upper End Surface 14 Opening 16 Base 18 Work Chuck 20 Holder 20a Fitting Part 22 Holder Drive Mechanism 24 Probe 24a Probe Main Body 24b Detection Ball 26 Electrical Insulation Member 28 x Axis Arm 28a; 28b Fitting part 30 x-axis direction drive mechanism 32 y-axis direction drive mechanism 34a; 34b long groove 36a; 36b x-axis ball screw 38 x-axis servo motor 40a; 40b ball nut 42 long groove 44 y-axis ball screw 46 y-axis servo motor 48 ball nut 50 control unit 52 x-axis rotary encoder 54 y-axis rotary encoder 56 electric circuit 56a electric wiring 56b power supply 56c resistance 58 detection circuit 60 photodiode 62 phototransistor 64 photocoupler 66 storage unit 68 It is a radical 19.

Claims (4)

[Scope of utility model registration request] 1. A conductive base comprising: a base; work chuck means disposed on the base for detachably gripping and fixing a conductive work; and a contact portion formed in a substantially spherical shape. And a tool holding means for holding the detection tool in an electrically insulated state, and a driving means for two-dimensionally moving and driving the tool holding means in a plane parallel to the base. An electric circuit means for electrically connecting the detection tool and at least the work and having a power source and a resistor; a potential detecting means connected to the electric circuit means for detecting the potential of the electric circuit means; The contact position between the detection tool and the work is detected two-dimensionally at the time when it is detected that the potential of the electric circuit means is lowered by the contact between the detection tool and the work by the means. Position detection means A storage unit for storing contact position information detected by the position detection unit, and a first predetermined distance along the evacuation direction separating the detection tool from the predetermined contact position detected by the position detection unit. After the evacuation operation, after the evacuation operation, the second predetermined distance is moved along the lateral direction intersecting the evacuation direction, and after the lateral movement operation, along the approaching direction approaching the work,
While moving until the contact position is detected by the position detecting means, the driving means is controlled so as to repeat this operation, and the detected contact position is stored in the storing means every time the contact position is detected. And a control means for detecting the outer peripheral shape of the work based on the contact position detected over the entire circumference of the work, wherein the diameter of the substantially spherical contact portion of the detection tool is the second
Is set to be larger than the distance on the surface of the work corresponding to the predetermined distance. 2. A conductive base comprising: a base; work chuck means disposed on the base for removably gripping and fixing a conductive work; and a contact portion formed in a substantially spherical shape. And a tool holding means for holding the detection tool in an electrically insulated state, and a driving means for two-dimensionally moving and driving the tool holding means in a plane parallel to the base. An electric circuit means for electrically connecting the detection tool and at least the work and having a power source and a resistor; a potential detecting means connected to the electric circuit means for detecting the potential of the electric circuit means; The contact position between the detection tool and the work is detected two-dimensionally at the time when it is detected that the potential of the electric circuit means is lowered due to the contact between the detection tool and the work by the means. Position detection means A storage unit for storing contact position information detected by the position detection unit, and a first predetermined distance along the evacuation direction separating the detection tool from the predetermined contact position detected by the position detection unit. After the evacuation operation, after the evacuation operation, the second predetermined distance is moved along the lateral direction intersecting the evacuation direction, and after the lateral movement operation, along the approaching direction approaching the work,
While moving until the contact position is detected by the position detecting means, the driving means is controlled so as to repeat this operation, and the detected contact position is stored in the storing means every time the contact position is detected. And a control means for detecting the outer peripheral shape of the work based on the contact position detected over the entire circumference of the work, and the second predetermined distance set by the control means corresponds to this. The workpiece shape automatic detection device is characterized in that the distance on the surface of the workpiece is set within a range smaller than the diameter of the substantially spherical contact portion of the detection tool. 3. A conductive base comprising: a base; work chuck means disposed on the base for removably gripping and fixing a conductive work; and a contact portion formed in a substantially spherical shape. And a tool holding means for holding the detection tool in an electrically insulated state, and a driving means for two-dimensionally moving and driving the tool holding means in a plane parallel to the base. An electric circuit means for electrically connecting the detection tool and at least the work and having a power source and a resistor; a potential detecting means connected to the electric circuit means for detecting the potential of the electric circuit means; The contact position between the detection tool and the work is detected two-dimensionally at the time when it is detected that the potential of the electric circuit means is lowered due to the contact between the detection tool and the work by the means. Position detection means The storage means for storing the contact position information detected by the position detection means and the detection tool are separated from the predetermined contact position detected by the position detection means in a state orthogonal to the close battle at the contact position. After retracting by a first predetermined distance along the retracting direction, after this retracting operation, it is moved by a second prescribed distance along a lateral direction orthogonal to this retracting direction, and after this lateral moving operation, orthogonal to this lateral direction. In this state, the work is moved along the approaching direction until the contact position is detected by the position detecting means, and the driving means is controlled to repeat this operation to detect the contact position. For each time, the storage unit stores the detected contact position, and based on the contact position detected over the entire circumference of the work, a control unit for detecting the outer peripheral shape of the work is provided. The diameter of the contact portion of the schematic sphere shape of the tool, the second
Is set to be larger than the distance on the surface of the work corresponding to the predetermined distance. 4. A conductive base comprising: a base; work chuck means disposed on the base for detachably gripping and fixing a conductive work; and a contact portion formed in a substantially spherical shape. And a tool holding means for holding the detection tool in an electrically insulated state, and a driving means for two-dimensionally moving and driving the tool holding means in a plane parallel to the base. An electric circuit means for electrically connecting the detection tool and at least the work and having a power source and a resistor; a potential detecting means connected to the electric circuit means for detecting the potential of the electric circuit means; The contact position between the detection tool and the work is detected two-dimensionally at the time when it is detected that the potential of the electric circuit means is lowered due to the contact between the detection tool and the work by the means. Position detection means The storage means for storing the contact position information detected by the position detection means and the detection tool are separated from the predetermined contact position detected by the position detection means in a state orthogonal to the close battle at the contact position. After retracting by a first predetermined distance along the retracting direction, after this retracting operation, it is moved by a second prescribed distance along a lateral direction orthogonal to this retracting direction, and after this lateral moving operation, orthogonal to this lateral direction. In this state, the work is moved along the approaching direction until the contact position is detected by the position detecting means, and the driving means is controlled to repeat this operation to detect the contact position. And a control unit that stores the contact position detected in the storage unit for each time and detects the outer peripheral shape of the work based on the contact position detected over the entire circumference of the work. It said second predetermined distance being set by means work shape automatic detection device, characterized in that set in a range smaller than the diameter of the contact portion of the schematic sphere shape of the detection tool.