JP6498943B2 - Safety monitoring device for press brake, press brake, and safety monitoring method - Google Patents

Description

  The present invention relates to a safety monitoring device for a press brake, a safety monitoring method, and the like for monitoring the safety of bending work of a workpiece using a press brake.

  In recent years, various developments have been made on press brakes, and the general configuration of a press brake will be described as follows.

  The press brake bends the workpiece by the cooperation of the upper die and the lower die, and includes a main body frame. A lower table is provided at the lower part of the main body frame, and this lower table holds the lower mold detachably on the upper side (upper side of the lower table). In addition, an upper table is provided on the upper part of the main body frame so as to face the lower table in the vertical direction. The upper mold is detachably held on the lower side (lower side of the upper table). Further, a foot switch as an activation switch that outputs (transmits) an activation signal for starting the relative lowering operation of the upper table is provided in the vicinity of the main body frame.

  In addition, there exist some which are shown to patent document 1-patent document 3 as a prior art relevant to this invention. The press brake according to the prior art uses a projector that projects laser light from one side in the width direction of the upper table toward the other side, and a receiver that receives laser light from the projector, It monitors the entry or approach of foreign matter other than the workpiece between the lower molds.

JP 2007-203310 A JP 2007-181875 A JP 2001-259744 A

  By the way, when an operator gets used to bending a workpiece using a press brake, the attention to the upper and lower molds, which is a danger source, is distracted and the work is bent. Confirming safety may be neglected. In such a case, if the upper table is lowered with respect to the lower table, an accident such as a finger being crushed by the upper mold and the lower mold may occur.

  Accordingly, the present invention provides a safety brake monitoring device and safety monitoring method for a press brake having a novel configuration capable of performing work bending work of a work using a press brake in a state where the safety awareness of the worker is sufficiently enhanced. The purpose is to provide.

A first feature of the present invention is a lower table provided at a lower portion of a main body frame and holding a lower mold on an upper side thereof, and provided at an upper portion of the main body frame so as to face the lower table vertically. An upper table that can move up and down relatively (movable in the vertical direction) and holds the upper mold on the lower side, and outputs a start signal for starting the relative lowering operation of the upper table In the safety monitoring device for press brakes, which is equipped with a press brake equipped with a start switch for (send) and monitors the bending work (safety of the bending work) of the work (metal plate), An imaging unit (imaging unit) that captures an image, and a feature part detection unit (feature part detection unit) that detects a feature part (position of the feature part) of the operator's face from the captured image captured by the imaging unit. A module), based on the position of the characteristic portion of a face of the worker detected by the feature region detecting unit, the orientation of the face of the worker, there in the region to be visually recognized in order to ensure the safety bending machining operations Then, there is an orientation determination unit (orientation determination module) for determining whether or not the operator is facing a predetermined visual recognition area set in advance as an area to be paid attention to, and an input of an activation signal from the activation switch on condition that, if the direction of the face of the operator by the orientation determining unit is determined to be facing the predetermined viewing area, the lowering operation permission unit for permitting a relative downward movement of said upper table ( A descent operation permission module).

  In addition to the first feature of the present invention, a corresponding position calculation that calculates a corresponding position corresponding to the orientation of the worker's face based on the position of the feature portion of the worker's face detected by the feature portion detection unit. A direction (corresponding position calculation module), wherein the orientation determination unit determines whether or not the operator's face is facing the predetermined visual recognition area based on the corresponding position calculated by the corresponding position calculation unit. It is desirable to judge.

  In addition, in the description of the specification and claims of the present application, “provided” means not only directly provided but also indirectly provided through another member. . Further, “detecting” means not only simply detecting but also continuing the detection state after detecting once, in other words, tracking.

According to the first feature of the present invention, during the work bending work of the workpiece using the press brake, the operator's face is imaged by the imaging unit, and the feature part detection unit is used to capture the operator's face from the captured image. Detect feature parts. Subsequently, the orientation determination unit determines whether or not the orientation of the operator's face is facing the predetermined visual recognition area based on the position of the feature portion of the operator's face. When it is determined that the orientation of the operator's face is facing the predetermined visual recognition area on the condition that an activation signal is input from the activation switch, the lowering operation permission unit causes the upper part to move upward. Allows relative lowering of the table. On the other hand, if it is determined that the orientation of the operator's face is not facing the predetermined visual recognition area, even if there is an input from the start switch, in principle, the lowering operation permission unit causes the upper table to Relative lowering movements are not permitted. As described above, the work bending work using the press brake can be performed in a state where the safety awareness of the worker is sufficiently enhanced.

  According to a second aspect of the present invention, there is provided a press brake for bending a workpiece (metal plate) by cooperation of an upper die and a lower die, and the safety monitoring for a press brake according to the first feature of the present invention. The gist is that the equipment is equipped.

  According to the 2nd characteristic of this invention, there exists an effect | action similar to the effect | action by the 1st characteristic of this invention.

According to a third aspect of the present invention, there is provided a lower table provided at a lower portion of the main body frame and holding a lower mold on an upper side thereof, and provided at an upper portion of the main body frame so as to face the lower table vertically. An upper table that can move up and down relatively (movable in the vertical direction) and holds the upper mold on the lower side, and outputs a start signal for starting the relative lowering operation of the upper table An imaging step for imaging a worker's face in a safety monitoring method for monitoring a work (sheet metal) bending work (bending work safety) using a press brake having a start switch for transmitting. And a feature part detection step for detecting a feature part (position of the feature part) of an operator's face from the captured image captured by the imaging step, and the feature part detection step. Based on the positions of the characteristic portions of the face of the detected operator I, the orientation of the face of the worker, an area to be visible in order to secure the bending of the processing operations, the operator attention An orientation determination step for determining whether or not the user is facing a predetermined visual recognition area set in advance as a power area, and an input of an activation signal from the activation switch, and the orientation determination step If the orientation of the face is determined to be facing the predetermined viewing area, and summarized in that with a, a descending operation enable step of permitting relative downward movement of the upper table.

  In addition to the third feature of the present invention, a corresponding position calculation for calculating a corresponding position corresponding to the orientation of the worker's face based on the position of the feature portion of the worker's face detected by the feature portion detecting step. Preferably, the orientation determination step determines whether or not the orientation of the operator's face is facing the predetermined visual recognition area based on the corresponding position calculated by the corresponding position calculation step.

According to a third aspect of the present invention, on the condition that an activation signal is input from the activation switch, the orientation determination step determines that the face of the operator is facing the predetermined viewing area. if it is, to allow relative downward movement of the upper table. On the other hand, if it is determined that the orientation of the operator's face is not facing the predetermined visual recognition area, even if there is an input from the start switch, in principle, the lowering operation permission unit causes the upper table to Relative lowering movements are not permitted. As a result, the work bending work using the press brake can be performed in a state where the safety awareness of the worker is sufficiently enhanced.

  According to the present invention, the workpiece can be bent using the press brake while the worker's safety awareness is sufficiently enhanced. Therefore, the upper mold and the lower mold are dangerous sources. Therefore, the safety of the work bending work can be improved.

FIG. 1 is a control block diagram of a press brake according to an embodiment of the present invention. 2A is a diagram illustrating a captured image captured by one (right side) CCD camera, and FIG. 2B is a diagram illustrating a captured image captured by the other (right side) CCD camera. FIG. 3A is a diagram for explaining extraction of a face region and detection of a characteristic part, and FIG. 3B is a diagram for explaining calculation of a corresponding position corresponding to the orientation of the operator's face. FIG. 4A is a diagram showing a state in which the orientation of the operator's face is facing a predetermined visual recognition area in a captured image captured by one CCD camera, and FIG. 4B is a diagram illustrating FIG. (A) is a figure which shows a mode that the direction of an operator's face is facing the predetermined | prescribed visual recognition area in the captured image imaged with the other CCD camera. FIG. 5A is a diagram showing a state where the orientation of the operator's face is not facing a predetermined visual recognition area in the captured image captured by one CCD camera, and FIG. 4B is a diagram illustrating FIG. (A) is a figure which shows a mode that the direction of an operator's face is facing the predetermined | prescribed visual recognition area in the captured image imaged with the other CCD camera. FIG. 6 is a schematic front view of the press brake according to the embodiment of the present invention. FIG. 7 is a schematic side view of the press brake according to the embodiment of the present invention. FIG. 8 is a flowchart for explaining the operation of the embodiment of the present invention and the safety monitoring method according to the embodiment of the present invention. FIG. 9 is a flowchart for explaining the operation of the embodiment of the present invention and the safety monitoring method according to the embodiment of the present invention. FIG. 10 is a flowchart for explaining the operation of the embodiment of the present invention and the safety monitoring method according to the embodiment of the present invention.

  Embodiments of the present invention will be described with reference to the drawings. In the drawings, “FF” is the forward direction, “FR” is the backward direction, “L” is the left direction, “R” is the right direction, “U” is the upward direction, and “D” is the upward direction. Pointing down each.

  As shown in FIGS. 6 and 7, the press brake 1 according to the embodiment of the present invention bends a plate-shaped workpiece (metal plate) W by the cooperation of the upper mold 3 and the lower mold 5. The main body frame 7 is used as a base. The main body frame 7 includes a pair of side plates 9 that are spaced apart from each other in the left-right direction (the width direction of the press brake 1), and a plurality of connecting members 11 that connect the pair of side plates 9.

  A lower table 13 extending in the left-right direction is provided at the lower portion of the main body frame 7. The lower table 13 has a lower mold 5 and a lower mold holder (illustrated) on the upper side (the upper side of the lower table 13). It is detachably held via (omitted). An upper table 15 extending in the left-right direction is provided on the upper portion of the main body frame 7 so as to be opposed to the lower table 13 in the vertical direction. The upper table 15 can be moved up and down (movable in the vertical direction) The upper die 3 is detachably held via a plurality of upper die holders (not shown) on the lower side (below the upper table 15). Furthermore, a hydraulic cylinder 17 (an example of a lifting actuator) for raising and lowering the upper table 15 is provided on the upper side of each side plate 9. Each hydraulic cylinder 17 includes a cylinder main body 19 fixed to the side plate 9, and a movable rod 21 provided on the cylinder main body 19 so as to be movable up and down and having a tip portion connected to the upper table 15. In the vicinity of the main body frame 7, a foot switch 23 is provided as an activation switch for outputting (transmitting) an activation signal for starting the lowering operation of the upper table 15 by driving each hydraulic cylinder 17. The foot switch 23 can be stepped on. A linear scale as a height position detector for detecting the height position of the upper table 15, in other words, the height position of the front end portion (lower end portion) of the upper mold 3, is provided at an appropriate position of one side plate 9. 25 is provided. An electric motor (not shown) may be used instead of the hydraulic cylinder 17 as an elevating actuator for elevating and lowering the upper table 15. Instead of configuring the upper table 15 to be movable up and down, the lower table 13 can be raised and lowered. You may comprise.

  A back gauge 27 for positioning the work W at a predetermined position in the front-rear direction (depth direction of the press brake 1) is provided on the back side (rear) of the lower table 13. The back gauge 27 includes an abutting member 29 that can abut the end surface of the workpiece W, and the abutting member 29 can be adjusted in position in the front-rear direction. A beam member 31 extending in the left-right direction is integrally connected between the cylinder main bodies 19 of the pair of hydraulic cylinders 17, and a guide member 33 extending in the left-right direction is provided on the beam member 31. It has been.

  As shown in FIG. 1, the press brake 1 includes a main controller (NC device) 35 that controls each hydraulic cylinder 17, back gauge 27, and the like based on a bending program. The main controller 35 includes a bending program, a memory (not shown) for storing mold information (information on the upper mold 3 and the lower mold 5), workpiece information (information on the workpiece W), and the bending program. CPU (not shown) for interpreting and executing the above. Further, a foot switch 23, a linear scale 25, and the like are connected to the main controller 35.

  The press brake 1 is equipped with a press brake safety monitoring device 37 for monitoring the bending work (safety of the bending work) of the workpiece W. And the concrete structure of the safety monitoring apparatus 37 for press brakes concerning embodiment of this invention is as follows.

  As shown in FIGS. 1, 2, and 7, the press brake safety monitoring device 37 is provided on the guide member 33 so that the position of the press brake 33 can be adjusted in the left-right direction, and images the upper body including the face of the operator OP. A pair of CCD cameras 39 is provided as an (imaging unit). Each CCD camera 39 is a color camera or a monochrome camera, and outputs (transmits) the captured image G taken as image data (moving image data). The number of CCD cameras 39 can be changed as appropriate. Instead of providing the CCD camera 39 on the guide member 33, or in addition to providing the CCD camera 39 on the guide member 33, the CCD camera 39 is provided on the lower table. 13, the upper table 15 or the helmet (not shown) of the operator OP may be provided.

  In addition to the pair of CCD cameras 39, the press brake safety monitoring device 37 includes an image processing controller 41 that executes image processing control based on a captured image G from the CCD camera 39. The image processing controller 41 includes: The main controller 35 is connected. Further, the image processing controller 41 interprets the image processing program, a memory (not shown) for storing a reference image (not shown) of the face area, a reference image (not shown) of the facial feature part, and the image processing program. CPU (not shown) to be executed. Note that the “reference image of the face area” may be either an assumed face image of a specific operator OP or an average adult face image. In the embodiment of the invention, it refers to the eyes of both eyes, but may be any part of the entire face other than the eyes of both eyes, such as the corners of both eyes, the ends of the mouth, etc., of image information such as brightness.

  The CPU of the image processing controller 41 converts the captured image G from each CCD camera 39 into a luminance image, but does not convert it into a luminance image when each CCD camera 39 is a monochrome camera. Then, the CPU of the image processing controller 41 interprets and executes the image processing program, thereby functioning as the feature part detection unit (feature part detection module) 43 and the corresponding position calculation unit (corresponding position calculation module) 45. A function, a function as a direction determination unit (direction determination module) 47, and a function as a descent operation permission unit (descent operation permission module) 49 are provided.

  Here, as shown in FIG. 1 and FIG. 3A, the characteristic part detection unit 43 extracts (detects) the face area FA from the captured image G captured by each CCD camera 39, and extracts the extracted face area FA. The eye I of both eyes (an example of the facial feature of the operator OP) is detected. Further, the extraction of the face area FA by the feature part detection unit 43 is executed by, for example, template matching using a reference image of the face area, and the detection of the eye head I of both eyes by the feature part detection unit 43 is performed on the feature part of the face. This is executed by template matching using a reference image. In addition, after once detecting the eye head I of both eyes by the characteristic part detection unit 43, when the detected state cannot be maintained, the face area FA is extracted again from the captured image G, and the extracted face area FA is extracted. Thus, the eye head I of both eyes is detected.

  As shown in FIG. 1 and FIG. 3B, the corresponding position calculation unit 45 is based on the position of the eyes I of both eyes of the operator OP (see FIG. 6) detected by the characteristic part detection unit 43. An intermediate position M of the eye I (an example of a corresponding position corresponding to the face direction of the operator OP) is calculated. The calculation is executed for each captured image G from each CCD camera 39. Instead of calculating the intermediate position M of the eyes I of both eyes, another corresponding position corresponding to the face direction of the operator OP may be calculated.

  As shown in FIGS. 1, 4 (a) (b), 5 (a), (b), and FIG. 6, the orientation determination unit 47 is an intermediate between the eyes I of both eyes calculated by the corresponding position calculation unit 45. Based on the position M, it is determined whether or not the face direction of the worker OP faces the predetermined visual recognition area EA. Specifically, the orientation determination unit 47 determines whether or not the intermediate position M between the eyes I of both eyes exists in the corresponding partial area SA corresponding to the predetermined visual recognition area EA in the face area FA. The determination is performed for each captured image G from each CCD camera 39. When the intermediate position M of the eyes I of both eyes based on the captured image G from at least one of the CCD cameras 39 is present in the corresponding partial area SA in the face area FA (FIGS. 4A and 4B). The orientation determination unit 47 determines that the face direction of the worker OP is facing the predetermined visual recognition area EA. On the other hand, when the intermediate position M of the eyes I of both eyes based on the captured image G from each CCD camera 39 does not exist in the corresponding partial area SA (see FIGS. 5A and 5B), the direction determination unit 47. Determines that the face direction of the operator OP does not face the predetermined visual recognition area EA. Here, the “predetermined visual recognition area EA” is an area to be visually recognized in order to ensure the safety of the bending work, and the size (including the width) of the upper mold 3 and the lower mold 5. Accordingly, this is an area set in advance as an area that the operator OP should pay attention to. The “corresponding partial area SA” is a face area FA that is assumed to have an intermediate position M between the eyes I of both eyes in the captured image G when the face of the operator OP faces the predetermined visual recognition area EA. This refers to a part of the area.

As shown in FIGS. 1 and 7, the descent operation permission unit 49 is operated by the direction determination unit 47 on the condition that an activation signal is input from the foot switch 23 by the stepping operation of the operator OP. When it is determined that the face of the OP faces the predetermined visual recognition area, the lowering operation of the upper table 15 by driving each hydraulic cylinder 17 is permitted. Further, the lowering operation permission unit 49 has a predetermined height interval between the upper mold 3 and the lower mold 5 (height interval between the molds) at the start of the lowering operation of the upper table 15 (immediately before starting the lowering operation). When the distance is less than the safe height interval, the lowering operation of the upper table 15 is permitted regardless of the determination result by the direction determination unit 47 on condition that the activation signal is input from the foot switch 23. is there. Here, the “predetermined safety height interval” refers to a height interval that ensures the safety of the bending work, and specifically, a height interval (for example, the operator OP's finger cannot enter) , 6 mm). The CPU of the main controller 35 detects from the linear scale 25 whether or not the height interval between the upper die 3 and the lower die 5 at the start of the lowering operation of the upper table 15 is equal to or less than a predetermined height interval. The determination is made based on the value (detection result).

  In addition to the pair of CCD cameras 39 and the image processing controller 41, the press brake safety monitoring device 37 includes an invalid button (operation button) 51 that outputs an invalid signal for invalidating the determination result by the direction determination unit 47. The invalid button 51 is preferably connected to the main controller 35 and can be pressed. When the press brake safety monitoring device 37 includes the invalid button 51, the descending operation permission unit 49 allows the foot switch when the invalid signal is input from the invalid button 51 by the pressing operation of the operator OP. 23, the lowering operation of the upper table 15 is permitted regardless of the determination result by the direction determination unit 47 on the condition that the activation signal is input from 23.

  Note that the CPU of the main controller 35 may have the function of the lowering operation permission unit 49 instead of the CPU of the image processing controller 41.

  Subsequently, the operation of the embodiment of the present invention including the safety monitoring method according to the embodiment of the present invention will be described with reference to FIGS. 8A and 8B to FIG. 10 and the like. Here, the safety monitoring method according to the embodiment of the present invention is a method for monitoring the bending work of the plate-like workpiece W using the press brake 1, and includes an imaging step, a characteristic part detection step, A corresponding position calculating step, a direction determining step, and a descent operation permission step are provided.

  The operation (operation) of the press brake 1 is started (step S101 in FIG. 8), and the upper table 15 is positioned at a predetermined height position for starting bending by driving each hydraulic cylinder 17 (in FIG. 8). Step S102). Thereby, the bending process operation | work of the workpiece | work W using the press brake 1 can be started.

  After the upper table 15 is positioned at a predetermined height, the foot switch 23 outputs an activation signal by an operation of the operator OP stepping on the foot (step S103 in FIG. 8). The activation signal from the foot switch 23 is input to the image processing controller 41 via the main controller 35.

  After the foot switch 23 outputs the activation signal, the face authentication process of the operator OP by the press brake safety monitoring device 37 is started (step S104 in FIG. 8). Then, the face authentication process of the worker OP is performed as follows.

  The upper body including the face of the worker OP is imaged by each CCD camera 39, and the captured image G is output as image data (moving image data) (step S201 in FIG. 10, imaging step). Then, when image data from each CCD camera 39 is input to the image processing controller 41, the feature region detection unit 43 extracts the face area FA from the captured image G, and the eyes I of both eyes from the extracted face area FA. (An example of the feature part of the face of the operator OP) is detected (step S202 in FIG. 10, feature part detection step). Subsequently, the corresponding position calculation unit 45 calculates an intermediate position M (an example of a corresponding position corresponding to the face direction of the operator OP) based on the position of the eyes I of both eyes (step in FIG. 10). S203, corresponding position calculation step). Then, the orientation determination unit 47 determines whether or not the orientation of the face of the operator OP is facing the predetermined visual recognition area EA based on the intermediate position M of the eyes I of both eyes (step S204 in FIG. 10, orientation determination). Step).

  After starting the face authentication process of the operator OP, the height interval between the upper mold 3 and the lower mold 5 at the start of the lowering operation of the upper table 15 by the CPU of the image processing controller 41 (the height interval between the molds). ) Is less than or equal to a predetermined safe height interval (step S105 in FIG. 8). When it is determined that the height interval between the upper mold 3 and the lower mold 5 at the start of the lowering operation of the upper table 15 is equal to or less than a predetermined safe height interval, the lower operation permitting unit 49 causes the upper table 15 to move upward. The lowering operation of the table 15 is permitted (step S106 in FIG. 8). Then, the face authentication process for the operator OP is finished (step S107 in FIG. 8), the hydraulic cylinders 17 are controlled by the main controller 35, and the upper table 15 is lowered at a low speed (step S108 in FIG. 8). The workpiece W can be bent.

If the height distance between the upper mold 3 and the lower mold 5 in lowering operation start of the upper table 15 is determined to exceed the predetermined safety height interval, the orientation of the face of the operator OP It is determined whether or not it faces a predetermined viewing area (step S109 in FIG. 9). When it is determined that the face direction of the worker OP is facing the predetermined visual recognition area, the lowering operation permission unit 49 permits the lowering operation of the upper table 15 (step S110 in FIG. 9). In addition, even if it is determined that the face direction of the operator OP does not face the predetermined visual recognition area, when the invalid signal is input from the invalid button 51, the descending operation permission unit 49 causes the upper table to be displayed. 15 is permitted (steps S111 and S110 in FIG. 9). Then, the face authentication process for the operator OP is finished (step S112 in FIG. 9), and the main controller 35 controls each hydraulic cylinder 17 to lower the upper table 15 (lower at high speed) (step S113 in FIG. 9). ), The workpiece W can be bent.

  On the other hand, when it is determined that the face direction of the operator OP does not face the predetermined viewing area and no invalid signal is input from the invalid button 51, the lowering operation permission unit 49 causes the lower table 15 to move downward. The operation of the press brake 1 is stopped by the main controller 35 without being permitted (step S114 in FIG. 9). In addition to stopping the operation of the press brake 1, for example, a warning lamp (an example of a notification unit) may be notified that the face of the operator OP is not facing a predetermined visual recognition area.

  In addition, after the process of step S108 in FIG. 8 and step S113 in FIG. 9, when the bending work of all the workpieces to be processed has not been completed (step S115 in FIG. 9), the process in step S103 in FIG. Return to.

As described above, the condition that there is an input of the start signal from the foot switch 23, when the direction of the face of the operator OP is determined to face the predetermined viewing area EA, the upper table 15 Allow descending movement. On the other hand, when it is determined that the face direction of the operator OP does not face the predetermined visual recognition area EA, in principle, the lowering operation of the upper table 15 is permitted even if there is an input from the foot switch 23. Never happen. Thereby, the bending work of the workpiece | work using the press brake 1 can be performed in the state which raised the safety consciousness of the operator OP sufficiently.

  When the height interval between the upper mold 3 and the lower mold 5 at the start of the lowering operation of the upper table 15 is equal to or less than a predetermined safe height interval, an activation signal is input from the foot switch 23 As a condition, the lowering operation of the upper table 15 is permitted. Further, when an invalid signal is input from the invalid button 51 by the pressing operation of the operator OP, the lowering operation of the upper table 15 is permitted on condition that an activation signal is input from the foot switch 23. To do. As a result, it is possible to eliminate as much as possible the situation where the operation of the press brake 1 stops despite the safety of the bending work being ensured.

  Therefore, according to the embodiment of the present invention, since the work bending work using the press brake 1 can be performed in a state in which the safety awareness of the worker OP is sufficiently enhanced, the worker's safety awareness is sufficient. Since the workpiece W can be bent using the press brake 1 in a state where the press brake 1 is raised, the bending of the workpiece W is avoided by avoiding the upper mold 3 and the lower mold 5 from becoming a danger source. Work safety can be improved.

  Although the safety of the bending work is ensured, it is possible to eliminate the situation where the operation of the press brake 1 is stopped as much as possible, so the productivity of the bending work of the workpiece W using the press brake 1 is maintained. can do.

  In addition, this invention is not restricted to description of the above-mentioned embodiment, It can implement in a various aspect. Further, the scope of rights encompassed by the present invention is not limited to the above-described embodiment.

G Imaged image FA Face area EA Predetermined visual recognition area SA Corresponding partial area I corresponding to the predetermined visual recognition area in the face area (characteristic part of the operator's face)
M Middle position of the eye (corresponding position corresponding to the orientation of the operator's face)
W Work 1 Press brake 3 Upper mold 5 Lower mold 7 Body frame 9 Side plate 13 Lower table 15 Upper table 17 Hydraulic cylinder 19 Cylinder body 21 Movable rod 23 Foot switch 25 Linear scale 31 Beam member 33 Guide member 35 Main controller ( NC device)
37 Safety monitoring device for press brakes 39 CCD camera (imaging unit)
41 Image processing controller 43 Characteristic part detection unit 45 Corresponding position calculation unit 47 Direction determination unit 49 Descent operation permission unit 51 Invalid button

Claims (7)

A lower table provided at the lower part of the main body frame and holding the lower mold on the upper side, and provided at the upper part of the main body frame so as to face the lower table vertically and can be moved up and down relative to the lower table. Bending of a workpiece is equipped with a press brake having an upper table that holds an upper mold on the lower side and a start switch that outputs a start signal for starting a relative lowering operation of the upper table. In a safety monitoring device for press brakes for monitoring machining operations,
An imaging unit for imaging an operator's face;
A feature part detection unit for detecting a feature part of an operator's face from a captured image captured by the imaging unit;
Based on the position of the feature part of the operator's face detected by the feature part detection unit, the orientation of the operator's face is an area to be visually recognized in order to ensure the safety of the bending work. A direction determination unit that determines whether or not the camera faces a predetermined visual recognition area that is set in advance as an area to be paid attention to ,
On condition that there is an input of the start signal from the start switch, when the direction of the face of the operator by the orientation determining unit is determined to be facing the predetermined viewing area, relative to the upper table A safety monitoring device for a press brake, comprising: a lowering operation permitting unit that permits a general lowering operation. A corresponding position calculation unit that calculates a corresponding position corresponding to the orientation of the operator's face based on the position of the feature part of the worker's face detected by the feature part detection unit;
The orientation determination unit determines whether or not the orientation of the operator's face is facing the predetermined visual recognition area based on the corresponding position calculated by the corresponding position calculation unit. The safety monitoring device for press brakes described in 1.   When the height interval between the upper die and the lower die is equal to or less than a predetermined safe height interval that ensures the safety of bending work, the lowering operation permission unit is a start signal from the start switch. 3. The press brake according to claim 1, wherein a relative lowering operation of the upper table is permitted regardless of a determination result by the direction determination unit, on the condition that the input of the first table is input. Safety monitoring device. An invalid button for outputting an invalid signal to invalidate the determination result by the orientation determination unit,
When the invalid operation signal is input from the invalid button, the descent operation permission unit, on the condition that the activation signal of the activation switch is input, regardless of the determination result by the direction determination unit, The safety monitoring device for a press brake according to any one of claims 1 to 3, wherein a relative lowering operation of the upper table is permitted. In press brakes that bend the workpiece by the cooperation of the upper mold and the lower mold,
A press brake comprising the press brake safety monitoring device according to any one of claims 1 to 4. A lower table provided at the lower part of the main body frame and holding the lower mold on the upper side, and provided at the upper part of the main body frame so as to face the lower table vertically and can be moved up and down relative to the lower table. Bending a workpiece using a press brake having an upper table that holds an upper die on the lower side and a start switch that outputs a start signal for starting a relative lowering operation of the upper table In a safety monitoring method for monitoring machining operations,
An imaging step of imaging an operator's face;
A feature part detection step of detecting a feature part of the face of the operator from the captured image captured by the imaging step;
Based on the position of the feature part of the operator's face detected by the feature part detection step, the orientation of the operator's face is an area to be visually recognized in order to ensure the safety of the bending work. A direction determination step for determining whether or not the image is directed to a predetermined visual recognition area set in advance as an area to be paid attention to ;
On condition that there is an input from the start switch, if it is determined that the orientation of the face of the operator is facing the predetermined viewing area by the orientation determining step, the relative descent of the upper table safety monitoring method characterized by comprising: a lowering operation enable step enables operation, the. A corresponding position calculating step for calculating a corresponding position corresponding to the orientation of the face of the operator based on the position of the characteristic portion of the operator's face detected by the characteristic portion detecting step;
The orientation determination step determines whether or not the orientation of the operator's face is facing the predetermined visual recognition area based on the corresponding position calculated by the corresponding position calculation step. Safety monitoring method described in 1.

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