Patent Publication Number: US-2021178541-A1

Title: Machine tool system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on Japanese Patent Application No. 2019-226301, the content of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a machine tool system. 
     BACKGROUND ART 
     There is a known machine tool that includes a cover for preventing scattering of chips and cutting fluid, that detects a state inside the cover to determine the adhering state and deposition state of the chips, and that changes the discharge direction of a cleaning liquid (for example, see PTL 1). 
     CITATION LIST 
     Patent Literature 
     {PTL 1} Japanese Unexamined Patent Application, Publication No. 2017-94420 
     SUMMARY OF INVENTION 
     One aspect of the present disclosure is directed to a machine tool system including a machine tool body and a control device, wherein: the machine tool body includes a cover that covers a machining region, chip expelling mechanisms that are disposed at a plurality of different positions inside the cover, that expel chips generated during processing, and a discharging ability of which is changeable, and a chip information obtaining unit that obtains information related to scattering directions of the chips during the processing; and in accordance with the information related to the scattering directions of the chips and obtained by the chip information obtaining unit, the control device controls the discharging ability of one of the chip expelling mechanisms corresponding to a direction in which a largest amount of the chips have scattered so as to be larger than the discharging ability of another of the chip expelling mechanisms. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an overall configuration diagram illustrating a machine tool system according to an embodiment of the present disclosure. 
         FIG. 2  is a plan view of the machine tool system in  FIG. 1 . 
         FIG. 3  is a diagram illustrating an example of an image obtained by a camera of the machine tool system in  FIG. 1 . 
         FIG. 4  is a diagram illustrating an region selected by analyzing the image in  FIG. 3  and in which a large amount of chips have scattered, the region being indicated by hatching. 
         FIG. 5  is a plan view illustrating a state in which a large amount of cleaning liquid is being discharged from nozzles corresponding to the region selected in  FIG. 4 . 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     A machine tool system  1  according to an embodiment of the present invention will be described below with reference to the drawings. 
     As shown in  FIG. 1 , the machine tool system  1  according to this embodiment includes a machine tool body  2  and a control device  3 . 
     The machine tool body  2  includes a table  4  on which a workpiece W (see  FIGS. 2, 3, and 5 ) to be processed is mounted, and a main spindle  7  attached to a main spindle head  6  supported on a column  5 , and to which a tool for processing the workpiece W is attached, and the machine tool body  2  is installed on a bed  8 . A machining region in which the processing of the workpiece W is performed is covered by a cover  9  for preventing chips A generated during the processing or a cutting fluid from scattering around. 
     On the bed  8 , slopes  10  inclining in a downward direction from a front side to a back side are provided on both sides of the table  4 . The slopes  10  initially receive the chips A generated during the processing or the cutting fluid, cause the received chips A to flow down by means of a cleaning liquid (coolant) B supplied as will be described later, and expel the chips A to the outside of the cover  9 . 
     As shown in  FIG. 2 , nozzles (chip expelling mechanisms)  11  for discharging the cleaning liquid B are provided at a plurality of positions inside the cover  9  of the machine tool body  2 . In the example shown in  FIG. 2 , for example, two nozzles  11  are provided on the front surface side of the cover  9 , and one nozzle  11  is provided at an upstream position, a center position, and a downstream position of each of the two slopes  10 . For example, the nozzle  11  at each position has discharge ports in three directions. This makes it possible to supply the cleaning liquid B over a wide area, and push away the chips A, etc. adhering to the wide area. 
     The machine tool body  2  includes a chip information obtaining unit  14  that obtains information related to the scattering directions of the chips A during the processing. The chip information obtaining unit  14  includes, above the main spindle head  6  in the cover  9 , a camera  12  that photographs the main spindle head  6  and the workpiece W from above, and an image processing unit (scattering direction calculation unit)  13  that processes an image (see, for example,  FIG. 3 ) obtained by the camera  12 . The image processing unit  13  is connected to the camera  12 . 
     The image processing unit  13  processes the image to extract the chips A and calculates a direction in which the largest amount of the chips A have scattered. Regarding information related to the direction, for example, as shown in  FIG. 4 , the image is divided into regions R 1  to R 8 , the number of which is equal to the number of the nozzles  11 , and the number of a region in which the largest amount of the chips A have scattered is selected. The region R 4  is selected in the example shown in  FIG. 4 . The selected region number is transmitted to the control device  3 . 
     The control device  3  stores information related to the nozzles  11  in association with the regions R 1  to R 8  and performs control, in accordance with the information related to the region selected by the image processing unit  13 , such that the discharge amount of the cleaning liquid B from a nozzle  11  corresponding to said direction is larger than the discharge amount from other nozzles  11 . Here, the associations between the regions and the nozzles  11  may be one-to-one or one-to-many. 
     With the thus-configured machine tool system  1  according to this embodiment, when cutting of the workpiece W by a tool is started, an image of the tool and the workpiece W photographed from above by the camera  12  disposed above is obtained, for example, at prescribed sampling intervals. The obtained images are transmitted to the image processing unit  13  and are subjected to image processing. By doing so, the chips A in each image are extracted, and on the basis of the sizes and the number of the extracted chips A, a region number indicating a direction in which the total weight of the scattered chips A is the largest is selected. 
     The selected region number is transmitted to the control device  3 . In the control device  3 , a nozzle  11  corresponding to the transmitted region number is selected, and for example, as shown in  FIG. 5 , the discharge amount of the cleaning liquid B from the selected nozzle  11  per unit time is made larger than those from the other nozzles  11 . Thus, there is an advantage in that, since even a large amount of the chips A that have scattered and fallen on the bottom part of the cover  9  are washed away by a large amount of the cleaning liquid B, it is possible to wash away the chips A before the deposition or adhesion of the chips A. 
     Regarding the other nozzles  11 , by causing the other nozzles  11  to discharge the cleaning liquid B with a lower discharge amount than that from the selected nozzle  11 , it is possible to wash away a small amount of the chips A to prevent the deposition or adhesion. 
     Note that, in this embodiment, the image processing unit  13  extracts the chips A in an image and calculates, on the basis of the sizes and the number of the chips A, a direction in which the largest amount of the chips A have scattered. Although the method for image processing in the image processing unit  13  may be arbitrary, for example, the scattering directions of the chips A may be estimated by obtaining and storing, in advance, an image when the cutting processing has not yet been performed, and comparing the image with an image obtained during the cutting processing. 
     Furthermore, although the scattering direction is calculated on the basis of the sizes and the number of the chips A, since the chips A having long lengths have the property that they become mutually entangled and easily deposited, the lengths of the chips A may be extracted from the image, and the discharge amount from a nozzle  11  in a direction in which the chips A having long lengths have scattered may be increased. 
     Furthermore, in this embodiment, although nozzles  11  that discharge the cleaning liquid B have been described as an example of chip expelling mechanisms, the chip expelling mechanisms are not limited to this embodiment, and a suction means for sucking the chips A or a chip conveyor that conveys the chips A may be employed. 
     REFERENCE SIGNS LIST 
     
         
           1  machine tool system 
           2  machine tool body 
           3  control device 
           9  cover 
           11  nozzle (chip expelling mechanism) 
           12  camera 
           13  image processing unit (scattering direction calculation unit) 
           14  chip information obtaining unit 
         A chip 
         B cleaning liquid