Patent Publication Number: US-2023147738-A1

Title: Control device for plate feeding device

Description:
TECHNICAL FIELD 
     The present invention relates to a control device for a plate material feeding device capable of measuring a transport amount of a plate material transported to a processing device by the plate material feeding device with high accuracy. 
     BACKGROUND ART 
     Patent Document 1 discloses a stamping system including a press mechanism, a material feeding mechanism, and a material dispenser. Then, in this stamping system, the material feeding mechanism feeds a material from the material dispenser through the material feeding mechanism to the press mechanism, measures the movement of the material in the material dispenser, and uses this to determine a desired timing of a material release mechanism including a material gripping mechanism which grips the material in cooperation with a feeding drive roll. 
     Citation List 
     Patent Literature 
     PATENT DOCUMENT 1: JP-A-2004-520934 
     SUMMARY OF INVENTION 
     Technical Problem 
     In the stamping system according to Patent Document 1, the material which has been transported from the material dispenser through the material feeding mechanism to the press mechanism moves due to vibration during press processing by the press mechanism. Thus, since the transport amount of the material which has been actually transported to the press mechanism is different from the transport amount of the material which has been transported from the material dispenser, there is a problem that the transport amount of the material which has been transported cannot be measured in the press mechanism. Moreover, since the material does not generally have a mark, such as a scale, for measuring the transport amount of the material which has been transported, there is a problem that the transport amount of the material which has been transported cannot be measured in the press mechanism. 
     Therefore, an object of the present invention is to solve the above problems and provide a control device for a plate material feeding device capable of measuring in a processing device such as a press device the transport amount of the plate material which has been transported with high accuracy. 
     Solution to Problem 
     According to an aspect of the present invention, a control device for a plate material feeding device which includes a first roll and a second roll, and is configured to clamp a plate material by the first roll and the second roll and transport the plate material according to the rotation of the first roll and the second roll, includes a control unit for controlling the rotation of the first roll and the second roll, a transmission unit for transmitting an electromagnetic wave toward the plate material, and a reception unit for receiving the electromagnetic wave reflected by the plate material, and the control unit measures a transport speed of the plate material during a predetermined period based on a frequency of the electromagnetic wave received by the reception unit, and measures a transport amount of the plate material based on the transport speed. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, the control unit measures the transport speed of the plate material by the difference between the frequency of the electromagnetic wave transmitted by the transmission unit and the frequency of the electromagnetic wave received by the reception unit. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, the transmission unit transmits electromagnetic waves from two directions toward the plate material, the reception unit receives the electromagnetic waves from the two directions reflected by the plate material, and the control unit measures the transport speed of the plate material by the difference between the frequencies of the reflected electromagnetic waves from the two directions. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, the reception unit transmits a transport speed-related signal based on the frequency of the received electromagnetic wave to the control unit. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, the transport speed-related signal has a period based on the transport speed of the plate material. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, when the plate material feeding device transports the plate material, the control unit controls the reception unit so as to transmit the transport speed-related signal to the control unit. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, when the plate material feeding device transports the plate material, the control unit controls the transmission unit so as to transmit the electromagnetic wave toward the plate material. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, the control unit controls the transportation of the plate material by the rotation of the first roll and the second roll, and the predetermined period is a period during which the plate material is transported by the rotation of the first roll and the second roll. 
     According to a specific example of the present invention, the plate material feeding device further includes a release device for releasing the plate material clamped by the first roll and the second roll, and in the control device for the plate material feeding device, the control unit controls the transportation of the plate material by the release device, and the predetermined period is a period during which the plate material is clamped by the first roll and the second roll. 
     According to a specific example of the present invention, in the control device for the plate material feeding device, the control unit determines the predetermined period based on a state signal from a processing device for processing the plate material transported from the plate material feeding device. 
     Advantageous Effect of Invention 
     According to the present invention, it is possible to measure in the processing device the transport amount of the plate material which has been transported with high accuracy without using a mark for measuring. 
     Other objects, features and advantages of the present invention will become apparent from the following description of the embodiments of the present invention taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic diagram of a control device for a plate material feeding device as an embodiment of the present invention. 
         FIG.  2 A  is a schematic diagram illustrating a reflection of an electromagnetic wave from a plate material as an embodiment. 
         FIG.  2 B  is a schematic diagram illustrating a reflection of an electromagnetic wave from a plate material as another embodiment. 
         FIG.  3    is a timing diagram of a transport speed-related signal as an embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments according to the present invention will be described with reference to the drawings. However, the present invention is not limited to those embodiments. 
     With reference to  FIGS.  1  to  3   , a control device  101  for a plate material feeding device  201  as an embodiment of the present invention will be described. The plate material feeding device  201  includes a first roll  202  and a second roll  203 , and clamps a plate material  100  by the first roll  202  and the second roll  203 . As illustrated in  FIG.  1   , the first roll  202  and the second roll  203  are rotated in the directions of the arrows, and the plate material  100  can be transported in the direction of the arrow according to the rotation of the first roll  202  and the second roll  203 . The plate material  100  is transported to a processing device  301  such as a press device by the plate material feeding device  201 , and is processed by the processing device  301 . The control device  101  includes a control unit  102  for controlling the rotation of the first roll  202  and the second roll  203  of the plate material feeding device  201 , a transmission unit  103  for transmitting an electromagnetic wave  105  toward the plate material  100 , and a reception unit  104  for receiving the electromagnetic wave  106  reflected by the plate material  100 . The control unit  102  is connected to the plate material feeding device  201  via a plate material feeding control signal line  107 , and controls the rotation of the first roll  202  and the second roll  203 . The control unit  102  measures a transport speed v of the plate material  100  during a predetermined period determined by the control unit  102  based on a frequency of the electromagnetic wave  106  received by the reception unit  104 . Subsequently, based on the measured transport speed v of the plate material  100 , the control unit  102  measures a transport amount of the plate material  100  transported to the processing device  301  during the predetermined period. Although in  FIG.  1   , the control unit  102  is provided separately from the plate material feeding device  201  and the processing device  301 , the control unit  102  may be built in the plate material feeding device  201  or the processing device  301 . Moreover, Although in  FIG.  1   , the transmission unit  103  and the reception unit  104  are built in the processing device  301 , the transmission unit  103  and the reception unit  104  may be built in the plate material feeding device  201  such that the transport amount of the plate material  100  can be measured before or after the plate material  100  passes through the first roll  202  and the second roll  203 , and can be provided at a required place. Further, the entire control device  101  may be built in the plate material feeding device  201  which transports the plate material  100 , or may be built in the processing device  301  such as the press device which processes the plate material  100  transported from the plate material feeding device  201 . 
     The control unit  102  may measure the transport speed v of the plate material  100  by the difference between the frequency of the electromagnetic wave  105  transmitted by the transmission unit  103  and the frequency of the electromagnetic wave  106  received by the reception unit  104 . In  FIG.  2 A , the transmission unit  103  transmits the electromagnetic wave  105  to the plate material  100  at an incident angle of θ, and the reception unit  104  receives the electromagnetic wave  106  reflected from the plate material  100  at a reflection angle of θ. Assuming that the frequency of the electromagnetic wave  105  transmitted by the transmission unit  103  is f T , and the speeds of the electromagnetic waves  105  and  106  are c, the frequency f R  of the electromagnetic wave  106  received by the reception unit  104  is expressed with the equation (1) by the Doppler effect.  
     
       
         
           
             
               f 
               R 
             
             ∼ 
             
               f 
               T 
             
             
               
                 1 
                 − 
                 
                   
                     2 
                     v 
                   
                   c 
                 
                 sin 
                 θ 
               
             
                
             ... 
             (1) 
           
         
       
     
     The control unit  102  performs mixing process to the electromagnetic wave  105  transmitted by the transmission unit  103  and the electromagnetic wave  106  received by the reception unit  104  such that a signal having a frequency of the equation (2) can be obtained from the difference f T  - f R  between the frequencies of these two electromagnetic waves  105  and  106 .  
     
       
         
           
             
               f 
               T 
             
             
               
                 2 
                 v 
               
               c 
             
             sin 
             θ 
                
             ... 
             (2) 
           
         
       
     
     The control unit  102  can measure the transport speed v of the plate material  100  from the frequency of the equation (2). Then, by measuring the transport speed v during the predetermined period, a length of the plate material  100  transported during the predetermined period, that is, the transport amount of the plate material  100  transported to the processing device  301  during the predetermined period can be measured. In this way, even if the plate material  100  does not have a mark, such as a scale, for measuring the transport amount, it is possible to measure the transport amount of the plate material  100  by the Doppler effect of the electromagnetic waves. 
     In  FIG.  2 B , the transmission unit  103  transmits the electromagnetic waves  105  toward the plate material  100  from two directions. In this case, the transmission unit  103  includes an electromagnetic wave source, a beam splitter, and a mirror. The electromagnetic waves generated from the electromagnetic wave source of the transmission unit  103  are split into two by the beam splitter. One electromagnetic wave  105  is transmitted as it is to the plate material  100  at an incident angle of θ, and the other electromagnetic wave  105  is reflected by the mirror and is transmitted to the plate material  100  at an incident angle of θ opposite to that of the one electromagnetic wave  105 . Assuming that the frequency of the electromagnetic waves  105  transmitted by the transmission unit  103  are f T , and the speeds of the electromagnetic waves  105  and  106  are c, the frequency f R1  of the electromagnetic wave  106  when the one electromagnetic wave  105  is reflected by the plate material  100  is expressed with the equation (3) by the Doppler effect.  
     
       
         
           
             
               f 
               
                 R1 
               
             
             ∼ 
             
               f 
               T 
             
             
               
                 1 
                 − 
                 
                   v 
                   c 
                 
                 sin 
                 θ 
               
             
                
             ... 
             (3) 
           
         
       
     
     Moreover, the frequency f R2  of the electromagnetic wave  106  when the other electromagnetic wave  105  is reflected by the plate material  100  is expressed with the equation (4) by the Doppler effect.  
     
       
         
           
             
               f 
               
                 R2 
               
             
             ∼ 
             
               f 
               T 
             
             
               
                 1 
                 + 
                 
                   v 
                   c 
                 
                 sin 
                 θ 
               
             
                
             ... 
             (4) 
           
         
       
     
     The electromagnetic waves  105  from the two directions are reflected by the plate material  100 , and the reception unit  104  receives the different electromagnetic waves  106  having two frequencies, being the electromagnetic waves  106  having the frequency f R1  and the electromagnetic wave  106  having the frequency f R2 . The control unit  102  performs heterodyne process to these two electromagnetic waves  106  received by the reception unit  104  such that a signal having a frequency of the equation (5) can be obtained from the difference f R2  - f R1  between the frequencies of these two electromagnetic waves  106 .  
     
       
         
           
             
               f 
               T 
             
             
               
                 2 
                 v 
               
               c 
             
             sin 
             θ 
                
             ... 
             (5) 
           
         
       
     
     The control unit  102  can measure the transport speed v of the plate material  100  from the frequency of the equation (5). Then, by measuring the transport speed v during the predetermined period, a length of the plate material  100  transported during the predetermined period, that is, the transport amount of the plate material  100  transported to the processing device  301  during the predetermined period can be measured. In this way, even if the plate material  100  does not have a mark, such as a scale, for measuring the transport amount, it is possible to measure the transport amount of the plate material  100  by the Doppler effect of the electromagnetic waves. 
     The transmission unit  103  is connected to the control unit  102  via an electromagnetic wave control signal line  108 , and the reception unit  104  is connected to the control unit  102  via a transport speed-related signal line  109 . The reception unit  104  receives the electromagnetic waves  106  having the frequencies such as the equations (1), (3), and (4), which are different from the frequency of the electromagnetic wave  105  transmitted by the transmission unit  103  as described above, and transmits the transport speed-related signal based on the frequency of the received electromagnetic wave  106  via the transport speed-related signal line  109  to the control unit  102 . For example, the reception unit  104  may transmit a signal related to the frequency of the received electromagnetic wave  106  such as the equations (1), (3), and (4) via the transport speed-related signal line  109  to the control unit  102 , or may transmit a signal related to the mixing process such as the equation (2) or the heterodyne process such as the equation (5) via the transport speed-related signal line  109  to the control unit  102 . These signals have a frequency, that is, a period, based on the transport speed v of the plate material  100  such as the equations (1) to (5). In addition, these signals may include an information related to the transport speed v of the plate material  100 . 
     When the plate material feeding device  201  transports the plate material  100 , the control unit  102  may control the reception unit  104  so as to transmit the transport speed-related signal to the control unit  102 . Moreover, when the plate material feeding device  201  transports the plate material  100 , the control unit  102  may control the transmission unit  103  so as to transmit the electromagnetic wave  105  toward the plate material  100 . When the plate material feeding device  201  starts transporting the plate material  100 , as illustrated in  FIG.  3   , the control unit  102  controls the transmission unit  103  so as to set a transport timing to H level via the electromagnetic wave control signal line  108  to transmit the electromagnetic wave  105  to the plate material  100 . The reception unit  104  receives the electromagnetic wave  106  reflected by the plate material  100 , and transmits a measurement result pulse, which is a transport speed-related signal, via the transport speed-related signal line  109  to the control unit  102 . The measurement result pulse may be AB phase outputs, the phases of which are shifted by 90° with respect to each other as illustrated in  FIG.  3   . The measurement result pulse has a frequency based on the transport speed v of the plate material  100 . The frequency becomes higher as the transport speed v of the plate material  100  becomes faster, and the frequency becomes lower when the transport speed v of the plate material  100  becomes slower. The transport amount of the plate material  100  transported to the processing device  301  is measured based on the measurement result pulse. Moreover, when the plate material feeding device  201  completes transporting the plate material  100 , as illustrated in  FIG.  3   , the control unit  102  controls the transmission unit  103  so as to set the transport timing to L level via the electromagnetic wave control signal line  108  to stop transmitting the electromagnetic wave  105  to the plate material  100 . In this way, it is possible to measure the transport speed v of the plate material  100  during a period during which the transport timing is set to H level, and it is possible to measure the transport amount of the plate material  100  transported to the processing device  301 . 
     In addition, the control unit  102  may directly transmit the transport timing to the reception unit  104 . In this case, when the control unit  102  sets the transport timing to H level, the reception unit  104  transmits the transport speed-related signal via the transport speed-related signal line  109  to the control unit  102 , and when the control unit  102  sets the transport timing to L level, the reception unit  104  stops transmitting the transport speed-related signal to the control unit  102 . Moreover, the control unit  102  does not have to transmit the transport timing to the transmission unit  103  and the reception unit  104 . In this case, although the reception unit  104  constantly transmits the transport speed-related signal via the transport speed-related signal line  109  to the control unit  102 , the control unit  102  extracts a period during which the transport timing is set to H level, from the transport speed-related signal, for the entire period, transmitted from the reception unit  104 , to measure the transport speed v of the plate material  100  based on the transport speed-related signal during the extracted period. Subsequently, based on measured the transport speed v of the plate material  100 , the transport amount of the plate material  100  transported to the processing device  301  during the extracted period is measured. 
     The control unit  102  controls the transportation of the plate material  100  by the rotation of the first roll  202  and the second roll  203  by controlling the rotation of the first roll  202  and the second roll  203  of the plate material feeding device  201  via the plate material feeding control signal line  107 . The predetermined period during which the transport amount of the plate material  100  transported to the processing device  301  is measured may be a period during which the plate material  100  is transported by the rotation of the first roll  202  and the second roll  203 . 
     The plate material feeding device  201  may further include a release device  204  for releasing the plate material  100  clamped by the first roll  202  and the second roll  203 . The release device  204  may be connected to either the first roll  202  or the second roll  203 , and the release device  204  raises and lowers the first roll  202  and/or the second roll  203  to clamp and release the plate material  100 . The control unit  102  controls the transportation of the plate material  100  by controlling the release device  204  via the plate material feeding control signal line  107 . The predetermined period during which the transport amount of the plate material  100  transported to the processing device  301  is measured may be a period during which the plate material  100  is clamped by the first roll  202  and the second roll  203 . 
     The processing device  301  processes the plate material  100  which has been transported from the plate material feeding device  201 . When the processing device  301  is the press device, the processing device  301  includes an upper mold  302  and a lower mold  303 , and the plate material  100  is punched out by the cooperation of the upper mold  302  and the lower mold  303 . When the process such as punch out process is performed by the processing device  301 , it is necessary to stop transporting the plate material  100 . Thus, the processing device  301  transmits a state signal regarding a state of the processing device  301 , that is, a signal indicating whether the plate material  100  should be transported or the transport of the plate material  100  should be stopped, via a state signal line  111  to the control unit  102 . Based on the signal from the processing device  301 , the control unit  102  determines a period during which the first roll  202  and the second roll  203  are rotated, a period during which the first roll  202  and the second roll  203  clamp the plate material  100 , or the like, and further, as described above, determines the predetermined period during which the transport amount of the plate material  100  transported to the processing device  301  is measured. The transport amount of the plate material  100  measured by the control unit  102  may be transmitted via a transport amount signal line  110  to the processing device  301 , or may be displayed on a display device such as a display. 
     The plate material feeding device  201  intermittently transports the plate material  100  to the processing device  301  by a fixed amount, and the control device  101  of the present invention can measures the transport amount of the plate material  100  transported to the processing device  301  by the plate material feeding device  201  with high accuracy. Then, the measured transport amount of the plate material  100  can be used to adjust the transport speed of the plate material  100  transported to the processing device  301 , the transport amount of the plate material  100  transported to the processing device  301 , a stop position of the plate material  100  stopped in the processing device  301 , and the like. 
     It should be further understood by persons skilled in the art that although the foregoing description has been made on embodiments of the present invention, the present invention is not limited thereto and various changes and modifications may be made without departing from the principle of the present invention and the scope of the appended claims. 
     REFERENCE SIGNS LIST 
     
         
           100  plate material 
           101  control device 
           102  control unit 
           103  transmission unit 
           104  reception unit 
           105  transmitted electromagnetic wave 
           106  reflected electromagnetic wave 
           107  plate material feeding control signal line 
           108  electromagnetic wave control signal line 
           109  transport speed-related signal line 
           110  transport amount signal line 
           111  state signal line 
           201  plate material feeding device 
           202  first roll 
           203  second roll 
           204  release device 
           301  processing device 
           302  upper mold 
           303  lower mold