JP5742173B2 - Conveying device and processing system using the same - Google Patents

Description

  The present invention relates to a gantry loader type conveying device that conveys a workpiece to a machine tool such as a lathe and a processing system using the conveying device.

2. Description of the Related Art Conventionally, in a transfer device that loads a workpiece into a machine tool, a camera is mounted on a loader, the type of the workpiece is determined and a machining program is selected (for example, Patent Document 1), and the machining status is recognized using the camera. A thing (for example, patent document 2) is proposed. In addition, with a fixedly installed camera, the material and posture of the workpiece gripped by the loader are determined, a machining program corresponding to the type of material is started, and the rotation angle position of the spindle is controlled according to the posture also corrected the program origin (e.g. Patent Document 3) are proposed.

JP-A-5-237743 JP 2008-006534 A JP 05-177494 A

  However, any of the conventional imaging / image processing methods requires a large number of processing steps to recognize the rotational phase with high accuracy, and requires a long processing time, which is not practical. For this reason, a positioning jig and a rotation phase determining jig at the work supply table are required for each work. In the absence of these jigs, the position of the workpiece and the rotational phase on the workpiece supply table will be shifted.

For example, as a method based on image processing, if there is a shift in the position or rotational phase of the workpiece on the workpiece supply table or if it is not known which of the types of workpieces is a plurality of types, the workpiece is imaged with a camera, If the workpiece is gripped by the loader according to the recognition result after accurately recognizing the rotation phase, workpiece type, etc., the workpiece can be gripped correctly and the workpiece can be correctly transferred to the machine tool.
However, processing image data captured by a camera and accurately recognizing the workpiece position, rotation phase, workpiece type, etc. requires a large number of processing steps for image processing, which takes time and is required for workpiece conveyance. The cycle time of machining becomes longer due to the influence of time.
Generally, at the outer periphery of the camera field of view, the imaging results are distorted due to the structural characteristics of the optical system, etc., and calibration is performed. However, even if calibration is performed, high accuracy can be obtained. difficult. For this reason, it is difficult to correctly recognize the workpiece if the center of the workpiece is greatly deviated from the center of the camera view. Even with a flat work, even if it is deviated from the center of the camera field of view, the influence is relatively small. However, with a high-height work, the image data is greatly distorted and may look completely different. Image processing can be corrected to some extent, but with such distorted image data, it takes time to recognize the workpiece with high accuracy.

  None of the techniques disclosed in Patent Documents 1 to 3 solve the above-described problems. In the technique of Patent Document 1, it is desired that a more accurate recognition method and processing be performed in a shorter time in order to eliminate a mistake by performing imaging a plurality of times and repeating a plurality of times as necessary. The technique of Patent Document 2 does not perform workpiece position recognition or phase recognition. In Patent Document 3, the workpiece is not gripped based on the determination result.

  That is, a technique for accurately determining position recognition, phase recognition, and heterogeneous discrimination based on an image and gripping a workpiece correctly based on the determination result has not yet been proposed. In addition, there is no mode in which recognition accuracy and processing time that are in a trade-off relationship can be selected according to the user's request according to the work.

An object of the present invention is to provide a transfer device that can recognize the rotation phase of a workpiece on a workpiece supply table and can grip the workpiece with a correct rotation phase by a chuck.
Another object of the present invention is to provide a transfer device that can quickly recognize the center position and rotation phase of the workpiece on the workpiece supply table with good accuracy and can correctly grip the workpiece.
Still another object of the present invention is to image a workpiece at a close position so that the center position and rotation phase of the workpiece can be recognized more accurately.
Still another object of the present invention is to enable accurate recognition of a rotational phase while shortening the image processing time.
Still another object of the present invention is to enable a workpiece to be gripped by a chuck according to the type of workpiece and an appropriate gripping position depending on the workpiece type.
Still another object of the present invention is to accurately recognize the center position and rotation phase of the workpiece on the workpiece supply table, to quickly grasp the workpiece, and to perform accurate machining quickly. It is to provide a processing system.

A first transport device (2) according to the present invention includes a guide rail (11) and a loader (12), and the loader (12) travels along the guide rail (11). A rod-like lifting body (15) installed on the traveling body (13) so as to be lifted and lowered, a loader head (16) provided at the lower end of the lifting body (15), and the loader head (16) The chuck (19) which is provided on the chuck and can hold the workpiece (W) and holds the workpiece (W) held by the chuck (19) with respect to the workpiece holder (6) of the machine tool (1). A transfer device (2) for carrying in
A rotation phase changing mechanism (17) for rotating the loader head (16) about the axis of the lifting / lowering body (15) is provided, and the loader (12) is imaged below the chuck (19). A camera (23) is provided, and an imaging / loader control means (33) for controlling the loader (12) according to the imaging result by performing imaging with the camera (23) is provided.
The rotational phase changing mechanism (17) is out with transmission mechanism for transmitting the upper and Dogen (17a) drive provided on the drive of said rod-like lifting member (15) to the loader head (16) (17b) Become.
The imaging / loader control means (33) determines the workpiece (W) from the imaging process for causing the camera to image the workpiece (W) on the workpiece supply table (3) and the image data obtained by the imaging process. Recognition processing for recognizing the rotation phase around the reference position, and adjustment processing for correcting the rotation phase of the chuck (19) together with the loader head (16) by the rotation phase change mechanism (17) according to the recognized rotation phase. It has the function to perform. The reference position of the workpiece (W) may be arbitrarily determined for each type of workpiece (W). For example, the centroid of the plane figure of the workpiece (W), the center of the portion to be gripped, a specific side The center, specific corners, etc.

  According to this configuration, the camera (23) causes the work (W) on the work supply table (3) to be imaged under the control of the imaging / loader control means (33). The rotational phase around the reference position of the workpiece (W) is recognized from the image data obtained by this imaging process. The rotational phase of the chuck (19) is corrected together with the loader head (16) by the rotational phase changing mechanism (17) according to the recognized rotational phase. Thereby, a workpiece | work (W) can be hold | gripped with a chuck | zipper (19) with a correct rotational phase. In this way, the rotational phase of the workpiece (W) on the workpiece supply table (3) can be recognized, and the workpiece (W) can be gripped at the correct rotational phase.

The second transport device (2) according to the present invention includes a guide rail (11) and a loader (12), and the loader (12) travels along the guide rail (11). A lifting body (15) installed on the traveling body (13) so as to be movable up and down, a loader head (16) provided at a lower end of the lifting body (15), and a loader head (16). The chuck (19) that holds the workpiece (W) and the workpiece (W) held by the chuck (19) is carried into the workpiece holder (6) of the machine tool (1). A conveying device (2),
A rotation phase changing mechanism (17) for rotating the loader head (16) about the axis of the lifting / lowering body (15) is provided, and the loader (12) is imaged below the chuck (19). A camera (23) is provided, and an imaging / loader control means (33) for controlling the loader (12) according to the imaging result by performing imaging with the camera (23) is provided.
The imaging / loader control means (33) includes a first imaging process for causing the camera (23) to image the workpiece (W) on the workpiece supply table (3) at a predetermined position of the loader (12); The first recognition process for recognizing at least the reference position (Wo) of the workpiece (W) from the image data obtained by the first imaging process, and the camera field of view at the recognized reference position (Wo) of the workpiece (W). A first adjustment process for adjusting the position of the loader (12) so that the center of the workpiece is positioned, and causing the camera to image the workpiece (W) on the workpiece supply table (3) again at the adjusted position. The second imaging process, the second recognition process for recognizing the rotation phase around the reference position of the workpiece (W) from the image data obtained by the second imaging process, and the above-mentioned according to the recognized rotation phase Rotation phase change mechanism (17) It has a function of performing the second adjustment process for correcting the rotational phase of the chuck (19) together with the head (16).

According to this configuration, under the control of the imaging / loader control means (33), the camera (23) attached to the loader (12) is positioned on the work supply table (3) at the position of the predetermined loader (12). The work (W) is imaged. At least the reference position (Wo) of the work (W) is recognized from the image data obtained by the first imaging process. Since the recognition of the reference position (Wo) of the workpiece (W) can be performed by simple image processing, it takes a short time. Next, the position of the loader (12) is adjusted so that the center of the camera field of view is positioned at the reference position (Wo) of the workpiece (W) recognized in the first recognition process. At this adjusted position, the camera (23) causes the work (W) on the work supply table (3) to be imaged again. The rotational phase around the reference position of the workpiece (W) is recognized from the image data obtained by the second imaging process. The recognition of the rotational phase requires a large amount of processing time to be performed accurately if the workpiece position varies. However, in the second imaging process, since the center of the camera field of view is generally located at the reference position (Wo) of the work (W), the rotational phase can be obtained with high accuracy by relatively simple image processing, and the processing time Can be done in a short time. At present, the processing capability of an arithmetic processing means such as a computer such as a personal computer that can be put into practical use in the transport device includes the process of performing the imaging twice as described above and adjusting the position of the loader during that time. Compared with the case where the rotational phase is calculated from a single imaging result performed in a state where the position and the center of the camera visual field do not match, the rotational phase can be calculated with high accuracy in a short time. The rotational phase of the chuck (19) is corrected together with the loader head (16) by the rotational phase changing mechanism (17) according to the recognized rotational phase. Thereby, a workpiece | work (W) can be hold | gripped with a chuck | zipper (19) with a correct rotational phase. In this way, accurate recognition of the reference position (Wo) and rotation phase of the workpiece (W) on the workpiece supply table (3) can be performed quickly, and the workpiece (W) can be gripped correctly. Note that position recognition may also be performed in the second imaging process. Thereby, the reference position (Wo) such as the center of the work (W) can be obtained with higher accuracy than the first imaging process.
The position recognition in the first recognition processing unit (42) and the second recognition processing unit (43) is preferably the center position of the workpiece (W), but it may not be the center position itself. The center position of the workpiece (W) can also be obtained based on these results by recognizing the reference position and recognizing the rotational phase.

  The camera (23) is preferably attached to the loader head (16). The camera (23) may be attached to the traveling body (13) of the loader (12). In that case, the position of the camera (23) is far from the work (W), and an image of the work (W) can be obtained with high accuracy. Is difficult. If the loader head (16) equipped with the chuck (19) is equipped with a camera (23), the workpiece (W) can be imaged immediately above the workpiece (W), and accurate imaging can be performed. A simple process can be performed with high accuracy. That is, if an image is taken from an oblique position, distortion occurs, so that correction is necessary and accuracy is deteriorated. However, if the image is directly above, distortion does not occur, and accurate imaging can be performed.

The imaging / loader control means (33) includes master registration means (40) for registering information on predetermined items for each type of work (W), and the imaging / loader control means (33) In the first recognition process, in addition to the recognition of the reference position (Wo) of the workpiece (W), the type of the workpiece (W) is selected from any of the workpiece types registered in the master registration means (40). , A process for determining an imaging condition when performing the second imaging process, and a recognition condition when performing the second recognition process according to the type of the determined workpiece (W) Either or both of the determination processes may be performed.
If the type of the workpiece (W) is registered and it can be determined which of the workpieces (W), the second imaging is performed according to the size of the workpiece (W), the size of the feature, or the like. It is possible to determine the imaging condition when performing the process and the process of determining the recognition condition when performing the second recognition process. By appropriately determining the search area as a recognition condition, unnecessary data can be omitted as image data, and as much necessary data as possible can be obtained. Therefore, the calculation of the rotation phase in the second recognition process that takes time for the calculation can be performed with a high accuracy in the shortest possible time. Examples of the imaging conditions include information for moving the camera field of view, and magnification when the camera has a magnification adjustment mechanism.

In the master registration means (40), information for determining a search area for performing the second recognition process for each type of work, and a work (W) when the work (W) is gripped by the chuck (19). The information for determining the grip position is registered, and the imaging / loader control means (33) stores the information in the master registration means (40) according to the type of the workpiece (W) determined in the first recognition process. Using the registered information, a search area for performing the second recognition process is determined, and a gripping position on the workpiece (W) when the chuck (9) grips the workpiece (W) may be determined. good.
If the type of the workpiece (W) is known, an appropriate search area can be determined, and the rotation phase can be calculated efficiently by determining the appropriate search area. Further, by appropriately determining the gripping position of the workpiece (W) according to the type of the workpiece (W), the workpiece (W) can be appropriately gripped.
Further, the master registration means (40) stores information for determining the camera field of view when performing the second imaging process for each type of work (W), and when the work (W) is gripped by the chuck (19). When the rotational phase is corrected by the rotational phase changing mechanism based on information defining the gripping position (Wa) in the workpiece (W), the rotational phase recognized in the second recognition process, and the information defining the gripping position. If the rotation angle is registered, each process can be performed easily and accurately. In particular, gripping of the workpiece by the chuck (19) can be performed according to the type of the workpiece (W) and an appropriate gripping position depending on the type of workpiece.
When there is a phase shift in the workpiece (W), it is not always appropriate to adjust the shift amount. For example, when there is a 55 ° phase shift, a 10 ° phase shift is necessary. There are cases where the workpiece gripping position (Wa) becomes appropriate simply by changing the angle. In such a case, if the rotation phase for correcting the rotation phase based on the rotation phase recognized as described above and the information defining the gripping position is registered in the master registration means (40), an appropriate rotation can be obtained. The phase can be adjusted with simple processing.

The processing system of this invention is provided with the conveyance apparatus (2) of one of the said structures of this invention, a machine tool (1), and a workpiece supply stand (3).
According to the machining system having this configuration, the accuracy of the reference position (Wo) of the workpiece (W) on the workpiece supply table (3) and the rotational phase accuracy can be achieved by the above-described functions and effects of the transfer device (2) of the present invention. Good recognition can be performed quickly, the workpiece (W) can be gripped correctly, and accurate machining can be performed quickly.

A first transport device according to the present invention includes a guide rail and a loader, the loader traveling along the guide rail, and a rod-shaped lifting body installed on the traveling body so as to be movable up and down. , A loader head provided at the lower end of the lifting body, a chuck provided on the loader head that is capable of a downward posture and grips the work, and the work held by the chuck with respect to the work holding part of the machine tool A carrying device for carrying in, wherein the loader head is provided with a rotation phase changing mechanism for rotating the loader head around an axis in the raising / lowering direction of the elevating body, and a camera for imaging the lower side of the chuck is provided on the loader. An imaging / loader control means is provided for controlling the loader according to the imaging result by performing imaging, and the rotational phase changing mechanism is provided above the rod-shaped lifting body. Vignetting was driving Dogen and its driving becomes in a transmission mechanism for transmitting the loader head, wherein the imaging loader control means includes: an imaging processing to image the workpiece on the work supply base to the camera, the imaging process Recognition processing for recognizing the rotational phase around the reference position of the workpiece determined from the image data obtained in step 1, and adjustment for correcting the rotational phase of the chuck together with the loader head by the rotational phase change mechanism according to the recognized rotational phase Because it has a function to perform processing, the workpiece rotation phase can be recognized and the workpiece can be rotated correctly even if it is placed at an arbitrary rotation phase, even if it is not adjusted to the same phase on the workpiece supply table. It can be gripped in phase.

A second transport device according to the present invention includes a guide rail and a loader. The loader travels along the guide rail, a lifting body installed on the traveling body so as to be lifted and lowered, and the lifting and lowering body. A loader head provided at the lower end of the body, a chuck provided on the loader head and capable of a downward posture and gripping the workpiece, and a conveyance for carrying the workpiece held by the chuck into the workpiece holding portion of the machine tool A rotation phase changing mechanism for rotating the loader head about an axis in the lifting direction of the lifting body, and a camera for imaging the lower side of the chuck is provided on the loader, and imaging is performed by this camera. And an image pickup / loader control means for controlling the loader according to the image pickup result, and the image pickup / loader control means is arranged at a predetermined loader position. A first imaging process for causing the camera to image the workpiece on the workpiece supply table; a first recognition process for recognizing at least a reference position of the workpiece from the image data obtained by the first imaging process; and the recognized workpiece First adjustment processing for adjusting the position of the loader so that the center of the camera field of view is positioned at the reference position, and second time for causing the camera to image the workpiece on the workpiece supply table again at the adjusted position. An imaging process, a second recognition process for recognizing the rotational phase around the reference position of the workpiece from the image data obtained by the second imaging process, and a loader by the rotational phase change mechanism according to the recognized rotational phase. Since it has the function of performing the second adjustment process that corrects the rotation phase of the chuck together with the head, it is not adjusted to the same position and the same phase on the work supply table, but is placed at an arbitrary position. Even carried-in, accurate recognition of the rotational phase between the reference position of the workpiece is rapidly performed, it is possible to grip the workpiece correctly.
When the camera is attached to the loader head, the workpiece can be imaged at a close position and further from directly above, and the workpiece reference position and rotational phase can be recognized with higher accuracy.

The imaging / loader control means includes master registration means for registering information on a predetermined item for each type of workpiece, and the imaging / loader control means is configured to detect the workpiece in the first recognition process. In addition to the recognition of the reference position, a process for determining which type of workpiece is one of the types of workpieces registered in the master registration unit, and a master registration unit according to the determined type of workpiece In the case of performing either or both of the imaging condition determination process when performing the second imaging process and the recognition condition determination process when performing the second recognition process using the information registered in , it is possible to perform appropriate imaging for each workpiece, between the time of image processing also shortened, it is possible to recognize the accurate rotational phase.

  Information for determining a search area when performing the second recognition process and information for determining a gripping position in the workpiece when gripping the workpiece with the chuck are registered in the master registration unit for each type of workpiece, The imaging / loader control means determines the search area when performing the second recognition process using the information registered in the master registration means according to the type of work determined in the first recognition process, In addition, when the gripping position of the workpiece is determined when gripping the workpiece with the chuck, even if a different workpiece is supplied, the workpiece can be gripped by the chuck and the proper gripping by the workpiece type and the workpiece type can be performed. It can be done according to the position.

  Since the processing system of the present invention includes the transport device having any one of the above configurations of the present invention, a machine tool, and a work supply table, the same position, the same phase, the same work type, and the front and back are on the work supply table. Even if it is not arranged and is carried in at an arbitrary position or a different workpiece is supplied, accurate recognition of the workpiece reference position and rotation phase can be performed quickly, and the workpiece can be gripped correctly. And high-precision processing can be performed quickly.

It is explanatory drawing which shows the one part front view of the processing system containing the conveying apparatus which concerns on one Embodiment of this invention, and the block diagram of the conceptual structure of the control system. (A) is a schematic block diagram of the control system, and (B) is a plan view showing the arrangement of the lighting fixtures. It is a flowchart of the main processes of the imaging / loader control means in the transport device. It is a top view of the processing system. It is a front view of the processing system. It is the enlarged front view and enlarged bottom view of the loader head of the conveyance apparatus. It is a side view which shows the relationship between the loader head and the main axis | shaft of the same conveying apparatus. It is explanatory drawing of the operation | movement which hold | grips the workpiece | work of the conveying apparatus. It is explanatory drawing of the relationship between the camera visual field and a workpiece | work in the same conveying apparatus. It is the top view and front view of an example of the workpiece | work conveyed with the conveyance apparatus. It is explanatory drawing of the phase change at the time of the workpiece | work holding | grip in the same conveying apparatus. It is the top view and front view of each workpiece | work registered into the master registration means of the conveyance apparatus. It is a time chart of the workpiece | work holding | grip operation | movement of the conveying apparatus. It is a time chart of the master registration process of the conveyance apparatus. It is a time chart of the calibration process of the conveyance apparatus.

Illustrating an embodiment of the present invention in FIG. 1 to FIG 5 and co. As shown in the conceptual configuration in FIG. 1, the machining system includes a machine tool 1, a transfer device 2, a workpiece supply table 3 for a workpiece W as a material, a workpiece carry-out table 4, the machine tool 1 and a transfer device. 2 and a control device 5 for controlling 2. The transport device 2 is mainly composed of a transport device main body 21A and the control device 5, and is further provided with a camera 23 and an image processing device 25.

As shown in FIGS. 4 and 5, the machine tool 1 is a parallel twin-axis lathe, two main shafts 6 and 6 that serve as work holding portions are provided in the center, and tool rests 7 and 7 are provided on both sides thereof. ing. In addition, a reversing device 8 for reversing the work W upside down is provided at the upper center.
The workpiece supply table 3 and the workpiece carry-out table 4 are respectively installed on both the left and right sides (X direction) of the machine tool 1. The workpiece supply table 3 moves, for example, a movable table 9 serving as a pallet or a transfer jig on each of which a plurality or one workpiece W is placed, along a circular path 10 on the upper surface by a movable table moving mechanism (not shown). It is a work feeder or a conveyor. The movable table 9 may be one in which a plurality of workpieces W are placed in a stacked state, and has moving wheels (not shown). Circular path 10 is long track shape in the longitudinal (Z-direction). The movable table moving mechanism is composed of, for example, a guide rail and driving means. The workpiece carry-out stand 4 is composed of, for example, a conveyer that conveys forward and backward.

  The transport apparatus 2 includes a transport apparatus body 2A that is a portion excluding the control system, and a control unit that controls the transport apparatus body 2A. In the example shown in the drawing, the transfer device main body 2A is of a gantry loader type. A rail 11 is provided above the machine tool 1 and above the workpiece supply table 3 and the workpiece carry-out table 4, and runs on the rail 11. The loader 12

  As shown in FIG. 1, the loader 12 is provided with a front / rear moving table 14 that is movable in the front / rear direction on a traveling body 13 that travels on a rail 11, and a rod-shaped lifting / lowering body 15 is moved up and down on the front / rear moving table 14. The loader head 16 is provided at the lower end of the lifting body 15. The traveling body 13, the front / rear moving table 14, and the lifting / lowering body 15 are driven for traveling, front / rear movement, and lifting / lowering by respective drive sources (not shown).

The loader head 16, the rotational phase changing mechanism 17 kicked set to the lifting body 15, the axis O around the lifting direction as a center of the lifting body 15, is it possible to change the rotational phase pivoted forward and reverse ing. The axis O is in the vertical direction. The rotation phase changing mechanism 17 includes a driving source 17a such as a motor and a transmission mechanism 17b for driving the driving source 17a.

  As shown in an enlarged view in FIG. 6, the loader head 16 is provided with a swivel chuck position replacement mechanism 18. In the loader head 16, a swivel swiveling body 18a is installed so as to be swivel around an inclined axis Q inclined by 45 ° with respect to the vertical axis O, and is swiveled by a swivel drive device 18b. . Chucks 19 are respectively provided on the lower surface and the front surface of the revolving body 18. The positions of the two chucks 19 and 19 can be interchanged by turning the turning body 18. The revolving body 18a and the revolving drive device 18b constitute a chuck position exchanging mechanism 18.

  Each chuck 19 has a plurality of chuck claws 20 that can advance and retreat in the radial direction with respect to the chuck center P (that is, the radial direction of the circle around the chuck center O), and a pusher 21. In the illustrated example, there are three chuck claws 20. The number of chuck claws 20 may be two, or four or more. The chuck claws 20 of each chuck 19 are driven to advance and retreat in the radial direction in synchronization with each other by a chuck opening / closing drive source 22 provided on each chuck 19. As shown in FIG. 7, the front surface is in a direction facing the main shaft 6 of the machine tool 1, and the chuck center P of the downward chuck 19 coincides with the axis O serving as the rotation center of the loader head 16. To do. The pusher 21 is a mechanism that allows the pusher plate 21a that presses the end face of the workpiece W to be moved forward and backward elastically. The pusher plate 21a is arranged so as not to interfere even if the chuck claw 20 moves, and has, for example, a three-arm shape as shown in FIG. 6B.

  In the loader head 16 having the above-described configuration, the camera 23 is installed downward on the side surface of the main body of the loader head 16. As shown in FIG. 2, the work supply base 3 is provided with an illumination tool 24 that illuminates the imaging range. For example, four illumination tools 24 are installed so as to surround the workpiece W from four directions. The camera 23 is connected to the image processing device 25. The image processing device 25 is connected to a monitor 26.

  Next, the control system will be described. In FIG. 2, the control device 5 is a device that controls the transport device main body 2A of the transport device 2, and includes an NC device 31 that is a computer-type numerical control device and a loader control device 32 that includes a computer-type programmable controller. Become. The NC device 31 and the loader control device 32 may be provided in the same computer, or may be provided in different computers and connected to each other via a LAN (local area network) or the like. . Further, the control device 5 may have a function of controlling the machine tool 1 (FIG. 1) in addition to the transport device body 2A. The image processing device 25, the camera 23, and the illumination tool 24 are controlled by the control device 5.

In FIG. 1, the control device 5 includes a computer and a program executed on the computer, and controls each process. The control device 2 </ b> A holds the workpiece W on the workpiece supply table 3 and passes it to the spindle 6. As the function achievement means for performing the above, the control device 5 and the image processing device 25 constitute an imaging / loader control means 33.
The imaging / loader control means 33 is a means for mainly performing each process shown in the flow chart of FIG. 3, and the configuration thereof will be described separately for each function achievement means together with FIG. First adjustment processing unit 35, second imaging processing command unit 36, second adjustment processing unit 37, recognition method switching unit 38, master registration processing unit 39, master registration means 40, and calibration time processing unit 41 are provided. doing. The master registration unit 40 may be provided in the image processing apparatus 25.
The image processing device 25 includes, for example, an independent computer and a program executed by the computer. The first recognition processing unit 42, the second recognition processing unit 43, the registration processing unit 44, and the calibration processing unit 45 are included. have.
In addition, each step S1-S6 of the flowchart of FIG. 3 was attached | subjected the code | symbol of each said part of FIG. 1 used as the means to perform the process of the step. Each of these units 34 to 45 has the following functions.
The recognition method switching unit 38, master registration processing unit 39, master registration means 40, calibration processing unit 41, registration processing unit 44, and calibration processing unit 45 are not necessarily provided.

  The first imaging process command unit 34 causes the camera 23 to image the workpiece W on the workpiece supply table 3 at the determined position of the loader 12. The first recognition processing unit 42 recognizes at least the reference position of the workpiece W (in this example, the position of the central axis Wo) from the image data obtained by the first imaging process. The reference position of the workpiece (W) may be arbitrarily determined for each type of workpiece (W). For example, the center of the portion to be gripped, the center of a specific side, a specific corner, and the like are used. . The first adjustment processing unit 35 adjusts the position of the loader 12 so that the center of the camera field of view is positioned at the recognized reference position (Wo) of the workpiece W.

  The second imaging process command unit 34 causes the camera 23 to image the workpiece W on the workpiece supply table 3 again at the adjusted position. The second recognition processing unit 43 recognizes the rotational phase of the workpiece W around the central axis Wo from the image data obtained by the second imaging process. The second adjustment processing unit 35 corrects the rotational phase of the chuck 19 together with the loader head 16 by the rotational phase changing mechanism 17 in accordance with the recognized rotational phase.

  The first imaging processing command unit 34, the first recognition processing unit 42, the first adjustment processing unit 35, the second imaging processing command unit 34, the second recognition processing unit 43, and the second adjustment processing. Each unit 35 is a means for performing the processing of each step in FIG. 3, and, as described above, the corresponding step is given the reference numeral of each unit.

More specifically, as shown in FIG. 8A, when the loader 12 grips the workpiece W on the workpiece supply table 3, the loader 12 is positioned at a predetermined position. An image is taken (step S1 in FIG. 3). The “predetermined position” is preferably the center of a range where the workpiece W is placed on the workpiece supply table 3. The first recognition processing unit 42 recognizes at least the reference position (position of the central axis Wo) of the workpiece W from the image data obtained by the first imaging process (S2). Since the reference position (Wo) of the workpiece W can be recognized by simple image processing, it takes only a short time. The relationship between the camera visual field R and the imaged image Wg of the workpiece W is shown in the lower part of the figure.
The first adjustment processing unit 35 adjusts the position of the loader 12 so that the center O23 of the camera field of view is located at the reference position (Wo) of the workpiece W recognized in the first recognition process. That is, the loader 12 is moved by a distance L between the workpiece reference position (Wo) and the camera visual field center O23. FIG. 8 shows a case where the vehicle is shifted only in the left-right direction (X direction). In this case, the traveling body 13 is driven, but when it is also shifted in the front-rear direction (Z direction), the front-rear moving table 14 is moved. (S3).

At this adjusted position, the camera 23 causes the workpiece W on the workpiece supply table 3 to be imaged again (S4). The rotational phase α around the central axis Wo of the workpiece W (FIG. 11A) is recognized from the image data obtained by the second imaging process (S5). When the planar shape of the workpiece W is circular throughout, the rotational phase is not related, but when it is non-circular, the rotational phase α is important for processing and gripping. The rotation phase α is a rotation angle with respect to a reference posture of the workpiece W that is arbitrarily determined. In the example of FIG. 11A, the posture indicated by the one-dot chain line in the drawing is the reference posture, and the workpiece W is rotated with respect to the reference posture by the rotation phase α.
The recognition of the rotational phase α requires a large amount of processing time to be performed accurately if the workpiece position varies. However, in the second imaging process, since the center O23 of the camera field of view is located at the reference position (Wo) of the workpiece W, the rotational phase α can be obtained with high accuracy and relatively simple processing. It takes a short time. At present, with the processing capability of the arithmetic processing means such as a computer having a performance that can be put into practical use in the transport apparatus including the cost, the process of performing the imaging twice as described above and adjusting the position of the loader 12 during that time The rotational phase can be calculated with high accuracy in a short time compared to the case where the rotational phase is calculated from a single imaging result performed in a state where the center of the work and the center of the camera field of view do not match.

In accordance with the recognized rotational phase α, the rotational phase change mechanism 17 corrects the rotational phase of the chuck 19 together with the loader head 16 (S6). Thereby, the workpiece | work W can be hold | gripped with the chuck | zipper 19 with a correct rotational phase. For example, in FIG. 11, the planar shape of the bottom of the workpiece W is triangular, and the triangular portion is gripped by the three chuck claws 20 of the chuck 19, but the rotational phase α is as shown in FIG. In the generated state, the position of the chuck claw 20 and the position of the center of each side of the workpiece W and the direction of the surface of the side do not match. For this reason, if the workpiece W is gripped as it is, the gripping posture of the workpiece W is not fixed, which is inaccurate. As shown in FIG. 11B, when the chuck claw 20 grips the workpiece W with the rotation phase of the chuck 19 correctly corresponding to each side of the workpiece W, the workpiece W is displaced with respect to the chuck 19 at the time of gripping. And can be gripped with high accuracy.
10 and 11, when the bottom portion is triangular and the upper portion is a cylindrical or columnar workpiece W, when the chuck claw 19 of the loader chuck 20 grips the three sides of the bottom portion, As shown in FIG. 11D, the chuck claw 6a of the spindle grips the cylindrical or columnar workpiece upper portion Wb with a phase different from that of the chuck claw 19 on the loader side. The middle phase between the gripping positions by the chuck claws 19 on the loader side is preferable. Contrary to the above, it is possible to grip the triangular bottom portion of the workpiece with the chuck claw 6a of the spindle and the workpiece upper portion Wb with the chuck claw 19 of the loader. Grasping with different phases.

In this way, accurate recognition of the reference position (Wo) of the workpiece W and the rotation phase α on the workpiece supply table 3 can be performed quickly, and the workpiece W can be gripped correctly.
Since the rotation phase of the chuck 19 is changed when the workpiece W is gripped, the gripping can be appropriately performed. However, if the chuck 19 is switched by the chuck position exchanging mechanism 18 in the direction facing the spindle 6, It cannot be passed to the spindle 6 correctly. Therefore, after gripping the workpiece W, the chuck 19 is returned to the original rotational phase as shown in FIG. 11C as part of the second adjustment process. Thereby, the workpiece | work W can be passed to the main axis | shaft 6 with a correct rotational phase.

  More specifically, each operation shown in the flowchart of FIG. 3 is performed while confirming a recognition error or the like between the control device 5 and the image processing device 25, as shown in the time chart of FIG.

  For the position recognition in the first recognition processing unit 42 and the second recognition processing unit 43, the center position of the workpiece W is desirable, but it may not be the center position itself. It is also possible to recognize the reference position, recognize the rotational phase, and obtain the center of the workpiece W based on these results.

In addition, each recognition process and adjustment process described above may be performed after registering each workpiece W in the master registration unit 40 as follows.
That is, the imaging / loader control unit 33 sets the type of the workpiece W to the master registration unit 40 in addition to the recognition of the reference position (Wo) of the workpiece W in the first recognition processing by the first recognition processing unit 42. Processing to determine which of the registered work types is performed. This type of work can be easily determined by a method such as pattern matching. The master registration unit 40 registers image data of various workpieces W, data obtained by processing the image and extracting characteristic portions, and the like. In addition to the above, the master registration unit 40 may register items described later.

Further, in the first adjustment processing unit 35, as one of the first adjustment processes, the camera field of view or the search area when performing the second imaging process (S4) according to the determined type of the workpiece W. Process to adjust. For example, as shown in FIG. 9A, when the image Wg when the first imaging process (S1) is performed is a very small part of the camera field of view R, as shown in FIG. In the twice imaging process (S4), the magnification of an optical mechanism (not shown) of the camera 23 is adjusted so that the image Wg is as large as possible within the range of the visual field R. Instead of adjusting the magnification, the search area Ra may be adjusted as shown in FIG.
If data for each type of workpiece W is registered in the master registration means 40 and it is possible to determine which of the workpieces W is included in the data, the second is determined according to the size of the type of workpiece W, the characteristic portion, and the like. It is possible to appropriately adjust the camera field of view R when performing the multiple imaging process. By appropriately adjusting the camera visual field R, unnecessary data can be omitted as image data, and as much necessary data as possible can be obtained. Therefore, the calculation of the rotation phase in the second recognition process that takes time for the calculation can be performed with a high accuracy in the shortest possible time.

In the master registration means 40, for each type of work W, information for determining the camera field of view or search area when performing the second imaging process (S4), and the work W when the work W is gripped by the chuck 19 are stored. The rotational phase is corrected by the rotational phase change mechanism 17 based on information defining the gripping position Wa (FIG. 10) and information defining the gripping position Wa with respect to the rotational phase recognized in the second recognition process (S5). You may register the rotation angle when performing, and the search area | region when recognizing by 2nd recognition process (S5). The imaging / loader control means 33 performs control according to the information registered in the master registration means 40.
As types of the workpiece W, for example, there are various types as shown in FIG. In the figure, a plan view and a front surface of each work W are shown as a pair so that a part of the work W is surrounded by a one-dot chain line.

As described above, the master registration unit 40 stores information for determining the camera field of view R when performing the second imaging process for each type of workpiece W, and the gripping position Wa on the workpiece W when the chuck 19 grips the workpiece W. Rotation when the rotational phase is corrected by the rotational phase changing mechanism 17 based on the information that defines the rotational phase recognized in the second recognition process (S5) and the information that defines the gripping position (Wa). If the angle is registered, each process can be performed easily and accurately. In particular, the workpiece W can be gripped by the chuck 19 according to the type of the workpiece W and an appropriate gripping position Wa depending on the workpiece type. If there is a phase shift in the workpiece W, it is not always appropriate to adjust the shift amount. For example, when there is a 55 ° phase shift, it is only necessary to change the 10 ° phase. The workpiece gripping position may be appropriate. In such a case, if the rotation phase at which the rotation phase is corrected is registered in the master registration means 40 based on the rotation phase recognized as described above and the information defining the gripping position, an appropriate rotation phase can be obtained. It can be adjusted with simple processing.

  The registration of the work W information in the master registration unit 40 may be performed manually from an input unit (not shown), or separately created data may be input via a communication unit or a medium. May be. Further, a master registration processing unit 39 and a registration time processing unit 44 may be provided and automatically performed. The master registration processing unit 39 is a unit that causes the camera 23 to pick up an image of the work W and registers the result data processed by the registration processing unit 44 in the master registration unit 40. Further, the master registration processing unit 39 may input data such as a gripping position from the input unit with respect to the data obtained as a result of processing by the registration processing unit 44. The registration processing unit 44 is a unit that performs image processing such as feature extraction for registering in the master registration unit 40 from the captured image.

  Specifically, the master registration processing unit 39, for example, in the procedure shown in the flowchart of FIG. 14, master registration job instruction, job load, name input instruction, name input, work information input instruction, work information input, image capture An instruction, image capture, export instruction, export (registration of the result in the master registration unit 40), and the like may be performed. The name input and work information input are performed manually from the input means.

An operation procedure for registration using the master registration processing unit 39 is, for example, the following procedure.
・ Mount the workpiece W on the spindle 6. When this state becomes the reference and is passed to the loader 12, it becomes the reference in the loader 12. In other words, the center of the workpiece W is the center of the workpiece W if the center of the chuck is the reference for the workpiece W and the center of gravity of the shape seen above is equal.
・ Set the workpiece W parameters. This is performed by the master registration processing unit 39. Parameters include, for example, registration number (automatic assignment), workpiece name, radius of the chucked part of workpiece, vertical length from the reference position of the workpiece (upper, lower), horizontal length from the reference position of the workpiece (right, left) ), The height of the chuck part of the workpiece, the number of equally divided parts (the number of equal shapes arranged in the circumferential direction), the workpiece material, information on single-sided processing or double-sided processing, and the presence / absence of feature point designation.
Automatic imaging and automatic test are started by the start instruction. The result is displayed on the monitor 26 (FIG. 2). If “OK”, save and complete automatic master registration. In the case of “NG”, manual image capture is required. Save the job.

The processing contents of the master registration processing unit 39 are performed as follows.
-Transport of the workpiece W to the image capture position. The workpiece W is transferred from the spindle 6 to the image pickup position (in the case of a spindle moving type lathe). The image capturing position is desirably a work supply table 3 such as a conveyor or a work feeder.
The movement of the camera 23 to the image capture reference position. The camera center is moved above the workpiece center, that is, the center of the chuck 19 of the loader 12, and the height from the chuck 19 or the camera 23 to the workpiece W is adjusted to the working distance WD (FIG. 8A). The distance WD in this case is a case where the workpiece supply table 3 including a workpiece feeder is used. In the case of the workpiece supply table 3 formed of a conveyor, the distance from the bottom surface may be used because it varies depending on the workpiece height.
-Automatic image capture. An area including a range based on the vertical and horizontal lengths of the workpiece W is imaged from the center position of the camera field of view, and used as a master image.
・ Recognition test. The workpiece W is chucked to shift the position / phase by a predetermined amount. The camera 23 is moved to the image recognition position. Position recognition and phase recognition are performed, and it is determined whether or not they match the amount of displacement. A shift test of a predetermined content is performed, and if it is within the standard, it is completed. If it is out of the standard, automatic capture is NG.

In Figure 1, the calibration processing unit 41, Ru hand Dandea performing calibration of lens distortion of the camera 23 (i.e. calibration). In the calibration process, the camera 23 captures an image, and the calibration processing unit 45 performs image processing for calibration. The processing by the calibration processing unit 41 is performed as shown in FIG. 15, for example.
As an operation procedure, the calibration sheet is placed at the reference position and a start instruction is given.
The calibration processing unit 41 captures a calibration image. Thereafter, calibration processing (relation between pixel coordinates and absolute coordinates in the camera, and absolute coordinates in the camera and the absolute coordinates of the loader position is performed). In the calibration sheet, dots (circles) and rectangles having a predetermined size are arranged at a predetermined interval, and absolute coordinates can be obtained.

  In FIG. 1, a recognition method switching unit 38 is a means for switching an image recognition method by mode selection based on an input from an input means. For example, modes such as “discrimination mode”, “priority mode”, and “front / back discrimination mode” are set. The “discrimination mode” is a multiple work designation mode (work type, front / back judgment) or a single work mode (correctness judgment). As the “priority mode”, for example, a high accuracy mode, an intermediate mode, and a high speed mode are provided. The “front / back discrimination mode” is a mode for determining whether the workpiece W has a front / back distinction. If there is a distinction between the front and back, register the master on the back.

DESCRIPTION OF SYMBOLS 1 ... Machine tool 2 ... Conveying apparatus 2A ... Conveying apparatus main body 3 ... Work supply stand 4 ... Work carrying out stand 5 ... Control device 6 ... Spindle (work holding | maintenance part)
DESCRIPTION OF SYMBOLS 11 ... Rail 12 ... Loader 13 ... Traveling body 14 ... Front-and-rear moving base 15 ... Elevating body 16 ... Loader head 17 ... Rotation phase change mechanism 18 ... Chuck position change mechanism 19 ... Chuck 20 ... Chuck claw 23 ... Camera 25 ... Image processing apparatus 31 ... NC device 32 ... loader control device 33 ... imaging / loader control means 40 ... master registration means α ... rotational phase O ... axis O23 ... center of camera field P ... chuck center R ... Karame field of view Wa ... gripping position Wo ... center Axis W ... Workpiece

Claims (6)

A guide rail and a loader, the loader being provided along a traveling body that travels along the guide rail, a rod-shaped lifting body that can be moved up and down on the traveling body, and a lower end of the lifting body A loader head, a chuck that is provided on the loader head and is capable of a downward posture and grips a workpiece, and a conveying device that carries the workpiece held by the chuck into a workpiece holding portion of a machine tool,
A rotation phase changing mechanism is provided for rotating the loader head about the axis of the lifting body in the up-and-down direction, and a camera for imaging the lower part of the chuck is provided in the loader. An imaging / loader control means for controlling the loader according to the
The rotational phase changing mechanism becomes in a transmission mechanism for transmitting the driving and drive Dogen provided in an upper portion of the rod-like lifting member to the loader head,
The imaging / loader control means is an imaging process for causing the camera to image a workpiece on the workpiece supply table, and a recognition process for recognizing a rotational phase around a reference position determined for the workpiece from image data obtained by the imaging process. And a function of performing adjustment processing for correcting the rotational phase of the chuck together with the loader head by the rotational phase changing mechanism according to the recognized rotational phase. A guide rail and a loader, the loader traveling along the guide rail, a lifting body installed on the traveling body so as to be movable up and down, and a loader head provided at a lower end of the lifting body; A chuck that is provided in the loader head and is capable of a downward posture and grips a workpiece, and a conveying device that carries the workpiece held by the chuck into a workpiece holding portion of a machine tool,
A rotation phase changing mechanism is provided for rotating the loader head about the axis of the lifting body in the up-and-down direction, and a camera for imaging the lower part of the chuck is provided in the loader. An imaging / loader control means for controlling the loader according to the
The imaging / loader control means includes a first imaging process for causing the camera to image the workpiece on the workpiece supply table at a predetermined loader position, and at least the workpiece from the image data obtained by the first imaging process. A first recognition process for recognizing a predetermined reference position, a first adjustment process for adjusting the position of the loader so that the center of the camera field of view is positioned at the recognized reference position of the workpiece, and the adjustment. A second imaging process for causing the camera to image the workpiece on the workpiece supply table again at a position, and a second phase for recognizing at least the rotational phase around the reference position of the workpiece from the image data obtained by the second imaging process. And a second adjustment process for correcting the rotational phase of the chuck together with the loader head by the rotational phase change mechanism according to the recognized rotational phase. Conveying apparatus according to claim.   The transport apparatus according to claim 2, wherein the camera is attached to the loader head.   The imaging / loader control means includes master registration means for registering information on a predetermined item for each type of workpiece, and the imaging / loader control means is configured to detect the workpiece in the first recognition process. In addition to the recognition of the reference position, a process for determining which type of workpiece is one of the types of workpieces registered in the master registration unit, and a master registration unit according to the determined type of workpiece And / or performing either or both of a process for determining an imaging condition when performing the second imaging process and a process for determining the recognition condition when performing the second recognition process. The conveying apparatus of Claim 2 or Claim 3.   Information for determining a search area when performing the second recognition process and information for determining a gripping position in the workpiece when gripping the workpiece with the chuck are registered in the master registration unit for each type of workpiece, The imaging / loader control means determines the search area when performing the second recognition process using the information registered in the master registration means according to the type of work determined in the first recognition process, The conveying device according to claim 4, wherein a gripping position on the workpiece when the workpiece is gripped by the chuck is determined.   A processing system comprising the transfer device according to any one of claims 1 to 5, a machine tool, and the work supply table.

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