JP5563804B2 - Feeder and press machine - Google Patents

Description

  The present invention relates to a feeder suitable for supplying a plate-like workpiece material to a press machine used for bending, punching, drawing, and the like, and a press machine including the feeder, and in particular, a plate thickness of the workpiece material. The present invention relates to a feeder having a function of monitoring changes, and a press machine that includes the feeder and does not cause a decrease in product accuracy due to a change in the plate thickness of a material to be processed.

  In precision machining using a press, a product inspection feedback system has been proposed in order to maintain product accuracy (see, for example, Non-Patent Document 1). According to this system, the accuracy of the product is measured from a photographed image of the actual product, and when it is determined that a defective product is found from the measurement data, the bottom dead center position of the slide of the press is determined based on the measurement data. The operation of the press is controlled in order to adjust it to an appropriate value.

  By the way, the plate-shaped workpiece continuously supplied to the press machine through the feeder causes a change in the plate thickness within a tolerance. In precision machining, it is possible to adjust the bottom dead center position of the slide of the press machine according to the change in the thickness of the workpiece, even if the change is within tolerance, in order to produce a higher precision product. desirable.

  However, in the conventional system, product accuracy is determined using product measurement data, and a predetermined work time is required for this determination. Therefore, a workpiece to be supplied to a processing machine such as a press machine. It was not possible to respond in real time to the changes in the plate thickness.

"Press Technology", published by Nikkan Kogyo Shimbun, October 1990, pages 104-108

  An object of the present invention is to provide a feeder that supplies a plate-shaped workpiece to a processing machine and that can output information on a change in plate thickness of the workpiece in real time.

  Another object of the present invention is to provide a pressing machine that does not cause a decrease in product accuracy due to a change in the thickness of a workpiece material.

  The feeder according to the present invention includes a frame and a nipping / conveying means which is supported by the frame and sandwiches and conveys the workpiece to continuously supply the plate-like workpiece to the processing machine. The means is provided with a pressure detector that outputs a signal corresponding to a pressure that changes according to the thickness of the workpiece when the means is actuated to clamp the workpiece.

  In the feeder according to the present invention, the plate thickness change of the workpiece to be supplied to the processing machine is output from the detector in real time as a pressure signal that changes in accordance with the plate thickness change. Therefore, the plate thickness change of the workpiece can be known in real time from this output signal.

  By controlling the operation of the processing machine using the output signal corresponding to the change in the plate thickness of the workpiece, stable machining accuracy can be expected for the processing machine regardless of the change in the plate thickness of the workpiece. Further, when the output signal exceeds a predetermined range, an alarm device that warns that can be activated, or the operation of the processing machine can be stopped based on the output signal.

The feeder is a gripper feeder. The gripper feeder includes a movable gripper that reciprocates along the conveyance path of the workpiece, and operates to clamp and release the workpiece in synchronization with the reciprocation, and the movable gripper. Includes a stationary gripper that operates in synchronization with the operation of the movable gripper so as to clamp the workpiece when the workpiece is released. In this gripper feeder, the pressure detector is provided in one of the movable gripper and the stationary gripper.

The movable gripper generally includes a sliding block supported by the frame to reciprocate along the conveyance path, a fixed jaw statically supported by the sliding block, and a joint with the fixed jaw. And a movable jaw that operates with a predetermined stroke to sandwich and release the workpiece. The stationary gripper includes a fixed jaw that is statically supported by the frame, and a movable jaw that operates with a predetermined stroke to clamp and release the workpiece in cooperation with the fixed jaw. In this case, either between the fixed jaw of the movable gripper and the sliding block supporting the fixed jaw, or between the fixed jaw of the stationary gripper and the frame supporting the fixed jaw, The pressure detector is arranged to receive a pressing force from the corresponding movable jaw. However, in order to simplify the configuration, it is desirable to provide the pressure detector between the fixed jaw of the stationary gripper and the frame that supports the fixed jaw.

  The press machine according to the present invention is a press machine provided with a feeder for continuously supplying a plate-shaped workpiece, and the feeder is supported by the frame and the frame, and the plate is formed on the processing machine. And nipping and conveying means for nipping and conveying the workpiece to continuously supply the workpiece. The clamping and conveying means has a pressure that acts as a reaction force on the clamping and conveying means when the clamping and conveying means is operated to clamp the workpiece and changes according to the thickness of the workpiece. A pressure detector that outputs a corresponding signal is provided. The press machine is controlled in operation based on the output signal of the pressure detector.

  In the press according to the present invention, a pressure signal that changes in accordance with a change in the plate thickness of the workpiece is output in real time from the detector provided in a feeder that supplies the workpiece to the press. Therefore, the press according to the present invention is controlled in real time by the pressure signal output in real time according to the plate thickness change of the workpiece. Therefore, it is possible to control the operation of the press machine quickly and appropriately according to the change in the plate thickness of the workpiece supplied to the press machine.

  The press machine can be controlled in operation based on a comparison between a preset pressure value and a pressure measurement value corresponding to an output signal from the pressure detector. Thereby, for example, when the plate thickness of the workpiece exceeds a predetermined range, the operation of the press machine can be stopped immediately.

  The press machine may be a press machine having a bottom dead center position correcting mechanism that corrects a bottom dead center position of a slide that reciprocates vertically on a bolster. In this press machine, the bottom dead center position correction of the slide is to correct the bottom dead center position so that the pressure value is within a predetermined range when the pressure measurement value by the pressure detector exceeds a predetermined value range. Can be operated. Thereby, regardless of the change in the plate thickness of the workpiece, a decrease in product accuracy due to the plate thickness change is surely prevented.

  According to the present invention, in a situation where a plate-shaped workpiece is supplied to the processing machine, information regarding the plate thickness change of the workpiece can be output in real time, so that the operation of the processing machine can be performed based on this output. It can control suitably.

  In addition, according to the present invention, it is possible to control the operation of a press machine that receives supply of the workpiece quickly and appropriately according to the thickness change of the workpiece. Can be reliably prevented.

It is a schematic diagram showing the entire press apparatus provided with a feeder according to the present invention, It is a perspective view which shows the feeder shown in FIG. FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. FIG. 4 is a cross-sectional view taken along line IV-IV shown in FIG. FIG. 5 is a cross-sectional view taken along line V-V shown in FIG. It is a surface view which expands and shows a part of press machine shown in FIG. FIG. 7 is a cross-sectional view obtained along line VII-VII shown in FIG. FIG. 7 is a cross-sectional view taken along line VIII-VIII shown in FIG. FIG. 7 is a cross-sectional view taken along line IX-IX shown in FIG. FIG. 7 is a cross-sectional view taken along line XX shown in FIG. It is a graph which shows the output characteristic of the pressure detector shown in FIG. It is explanatory drawing which shows the other feeder of this invention roughly, (a) shows the state in a non-clamping position, (b) shows the state in a clamp position, respectively.

  The press apparatus according to the present invention includes a press machine 10. As shown in FIG. 1, the press machine 10 includes a lower frame 14 provided with a bolster 12 and an upper frame 16 supported by the lower frame at an interval. On the bolster 12, a lower mold 18a of the mold 18 is placed. As is well known in the art, the upper frame 16 has a reciprocating motion device 22 for reciprocating the slide 20 between its top dead center and bottom dead center via a motion conversion mechanism such as a crank mechanism. Is installed. An upper die 18b of the mold 18 is attached to the lower surface of the slide 20 so as to face the lower lower die 18a. The upper die 18b is directed toward and away from the lower die 18a by the operation of the reciprocating motion device 22. Reciprocate in the direction. The lower mold 18a and the upper mold 18b constitute a lower processed part and an upper processed part, respectively, and both the molds 18a and 18b constitute a processed part of the press machine 10.

  A workpiece 28 such as a strip-shaped steel material is intermittently supplied between the flat mating surfaces 24 of the molds 18 a and 18 b facing each other via a feeder 26. The reciprocating device 22 reciprocates the upper die 18b toward and away from the lower die 18a in synchronization with the intermittent supply of the workpiece 28 described above. Due to this reciprocating motion, the workpiece 28 is pressed between the lower mold 18a and the upper mold 18b so that the corresponding mold surface portions (not shown) formed on the mating surface 24 between the mating surfaces 24 of both molds. To be processed according to

  This processing includes mechanical press processing such as drawing processing, bending processing, punching processing, crushing processing, or shearing processing. In any case, the processing accuracy of the product is that of the slide 20 to which the upper die 18b is attached. It is greatly affected by the height of the bottom dead center. In shear processing, the processing accuracy of the cut surface is greatly affected by the height of the bottom dead center. Moreover, when the press machine 10 is a shearing machine, a lower process part means a lower blade and an upper process part means an upper blade. Such a press 10 is provided with a conventionally well-known servo motor 30b for adjusting the bottom dead center position in relation to the reciprocating motion device 22.

  The servo motor 30b is controlled by the control device 32. The control device 32 is basically provided in the feeder 26, and outputs a pressure signal corresponding to the thickness information about the workpiece 28, and the thickness obtained by the pressure detector. And an arithmetic processing unit 36 that generates an appropriate control signal based on the information, and a motor control circuit 38 that controls the operation of the servo motor 30b with the control signal obtained by the arithmetic processing unit.

  As will be described later, the pressure detector 34 is provided in the feeder 26 and is incorporated in association with means for sandwiching and transporting the workpiece 28. The arithmetic processing unit 36 compares the thickness information signal corresponding to the pressure information from the pressure detector 34 with the reference value, and outputs the difference signal to the motor control circuit 38. The motor control circuit 38 outputs an operation control signal based on the output from the pressure detector 34 to the servo motor 30b. The servo motor 30b adjusts the slide bottom dead center position of the reciprocating device 22 to an appropriate value based on the operation control signal from the motor control circuit 38, as will be described later. Therefore, the motor control circuit 38 and the servo motor 30b constitute a part of the bottom dead center position adjusting mechanism.

  As an example of the feeder, basically, a gripper feeder 26 described in Japanese Patent Publication No. 7-24891 is shown in FIGS. FIG. 2 is a perspective view of the feeder 26. The feeder 26 is used to intermittently and quantitatively supply a long workpiece 28 such as a metal plate to a processing machine such as the press machine 10. The press machine 10 and the feeder 26 constitute a press device.

  As shown in FIGS. 2 to 4, the feeder 26 is entirely supported by a rectangular frame 112, a guide member 114 that is supported by the frame and arranged along the conveying direction of the workpiece 28, and the frame. , And a drive cam shaft 116 (see FIG. 4) disposed along the conveying direction of the workpiece 28. In the illustrated example, the upper side and one side of the rectangular frame 112 are open. In addition, guide slits 112b and 112b are formed in the pair of end walls 112a and 112a facing each other in the transport direction, and the workpiece 28 is guided through the slits.

  As shown in FIG. 4, the guide members 114 are disposed in the frame 112 in pairs parallel to each other. The pair of guide members 114 has a circular cross-sectional shape and cuts the frame 112 longitudinally.

  The driving cam shaft 116 is transmitted with a driving torque from a driving source through a driving circulation belt (not shown). Due to this driving rotational force, the driving cam shaft 116 rotates integrally with the cam member 118 fixed to the cam shaft in either the clockwise direction or the counterclockwise direction.

  As shown in FIGS. 2 and 3, the guide member 114 is provided with a movable gripper 122 and a stationary gripper 124. As shown in FIGS. 2 to 4, the movable gripper 122 has a sliding block 128 slidably supported on the guide member 114 and a first operation for reciprocating the sliding block along the guide member 114. The apparatus 130 (refer FIG. 4), the fixed jaw 132 and the movable jaw 134 which were supported by the sliding block 128, and the 2nd actuator 136 (refer FIG. 4) for operating this movable jaw are provided.

  The first actuating device 130 includes a crank arm 130 a driven by a drive source (not shown) and a pivot 130 b that connects the crank arm to the sliding block 128. As is well known in the art, the first actuating device 130 moves the sliding block 128 pivotally attached via the pivot 130b with a predetermined stroke along the guide member 114 as the crank arm 130a swings. The stationary gripper 124 is moved back and forth in a direction away from it. The sliding block 128 is provided with a support portion 128a for holding the fixed jaw 132 at a distance from the movable jaw 134 above the movable jaw 134, and the fixed jaw 132 is fixed to the support portion. . Further, as in the prior art, the movable jaw 134 is supported on the sliding block 128 so as to be movable toward and away from the fixed jaw 132.

  Below the sliding block 128, as shown in FIGS. 3 and 4, a movable rail 138 of the second actuating device 136 is disposed. The movable rail 138 is made of a cylindrical member having a rectangular outer cross section and extends over the entire stroke of the sliding block 128. On the upper surface of the movable rail 138, as shown in FIG. 3, rolling rollers 138a whose rotation shaft is supported by the movable rail 138 are arranged at intervals in the longitudinal direction of the movable rail 138.

  As shown in FIG. 5, the movable rail 138 is supported at one end of a swing arm 140 having a swing shaft 140a supported by the frame 112 via a pivot shaft 140b. As shown in FIGS. 4 and 5, a cam follower 142 is supported on the other end of the swing arm 140 via a pivot shaft 140c. The cam follower 142 is reliably engaged with the cam member 118 by receiving the biasing force of the biasing means 144 such as a compression coil spring.

  The rotation of the cam member 118 causes the movable rail 138 to reciprocate up and down with a constant stroke via the swing arm 140. This reciprocation is performed synchronously with the reciprocation along the guide member 114 of the sliding block 128 as is well known in the art.

  As shown in FIG. 3, on the movable rail 138 that reciprocates in the vertical direction, a rolling element 148 of a follower member 146 supported by a sliding block 128 via a horizontal pivot 146a so as to be swingable. Engage. The rolling element 148 is pivotally attached to the follower member 146 via its horizontal pivot 148a. Engagement between the rolling element 148 of the follower member 146 and the rolling roller 138 a of the movable rail 138 is ensured by the biasing force of the compression coil spring 150 inserted between the sliding block 128 and the follower member 146. The

  The rolling element 148 facilitates reciprocation along the guide member 114 of the sliding block 128 with respect to the movable rail 138. Further, the movable rail 138 swings the follower member 146 around the pivot 146a by the reciprocating motion in the vertical direction accompanying the swing of the swing arm 140. When the follower member 146 overcomes the biasing force of the compression coil spring 150 and swings around the follower member 146, the follower member 146 is movable so that the movable jaw 134 holds the workpiece 28 between the fixed jaw 132 and the follower member 146. The jaws 134 are actuated synchronously with the aforementioned reciprocating movement of the sliding block 128 toward and away from the fixed jaws 132. Thereby, the movable jaw 134 of the movable gripper 122 is synchronized with the reciprocating motion of the sliding block 128, and the top dead center position closest to the fixed jaw 132 and the bottom dead center position farthest from the fixed jaw 132 are arranged. Move up and down between.

  As shown in FIG. 3, the stationary gripper 124 includes a stationary block 160 fixedly supported by the frame 112, a fixed jaw 162 and a movable jaw 164 supported by the stationary block, and an operation for operating the movable jaw. A third actuating device 166.

  The stationary block 160 is provided with a support portion 160a, and a fixed jaw 162 is fixed to a substantially central portion of the support portion. Further, the movable jaw 164 is disposed on the stationary block 160 so as to face the fixed jaw 162. In the illustrated embodiment, a pressure detector 34 is incorporated in connection with the stationary block 160 of the stationary gripper 124, as will be described in detail later.

  The movable jaw 164 is supported by the stationary block 160 so as to be movable toward and away from the fixed jaw 162 in the same manner as in the movable gripper 122 described above, and a third actuator is provided at the lower end of the movable jaw 164. 166 is arranged.

  The outline of the third actuator 166 of the stationary gripper 124 will be described with reference to FIGS. 3 and 5. The third actuating device 166 includes a swing lever 168 having a horizontal swing shaft 168a. The upper surface of one end of the swing lever 168 can contact the lower surface of the movable jaw 164, and the lower surface of the one end of the swing lever 168 has a first push-up rod 172 that receives the biasing force of the compression coil spring 170. A receiving seat 174 that forms a spherical pair with the upper end is provided. Therefore, the one end of the swing lever 168 receives the biasing force of the compression coil spring 170. Thereby, the movable jaw 164 receives an acting force toward the fixed jaw 162 so as to sandwich the workpiece 28 between the movable jaw 164 and the fixed jaw 162.

  In addition, a receiving seat 178 that forms a spherical pair with the upper end of the second push-up rod 176 is provided on the lower surface of the other end of the swing lever 168. As shown in FIG. 5, the lower end of the push-up rod 176 engages with a swing arm 180 having the swing shaft 140a as a common shaft. At one end of the swing arm 180, a receiving portion 180a (see FIG. 3) that forms a spherical pair with the lower end of the push-up rod 176 is formed. A cam follower 182 is pivotally attached to the other end of the swing arm 180 via a pivot 180a. The cam follower 182 engages with a cam member (not shown) fixed to the drive cam shaft 116 as is well known in the art.

  Therefore, as the cam member engaged with the cam follower 182 of the third actuator 166 is rotated, the swing arm 180 swings around the swing shaft 140a by overcoming the biasing force of the compression coil spring 170. To do. By swinging the swing arm 180, the movable jaw 164 moves up and down between a top dead center position closest to the fixed jaw 162 and a bottom dead center position farthest from the fixed jaw 162. Accordingly, the stationary gripper 124 holds the workpiece 28 in cooperation with the fixed jaw 162 when the movable jaw 164 is at the top dead center position at the stationary position, and the workpiece gripped at or near the bottom dead center position. It operates with a certain stroke so as to release the material 28.

  The above described movable gripper 122 and stationary gripper 124 are clamped and released by the workpiece 28 and the transporting stroke along the transporting direction of the movable gripper 122 is synchronized with each cam member 118 fixed to the driving camshaft 116 and the like. Is achieved as in the prior art.

  Therefore, as described above, the stationary gripper 124 releases the workpiece 28 when the movable gripper 122 holds the workpiece 28, and the stationary gripper 124 when the movable gripper 122 releases the workpiece 28. So that the workpiece 28 is sandwiched, the movable gripper 122 is sandwiched and released, the movable gripper 122 is reciprocated, and the stationary gripper 124 is sandwiched and opened. Thereby, the intermittent supply of the workpiece 28 to the press machine 10 becomes possible.

  The pressure detector 34 is provided, for example, in the movable gripper 122 or the stationary gripper 124. Prior to the description thereof, an example of a detailed configuration of the press 10 that receives operation control based on an output signal from the pressure detector 34. Will be described with reference to FIGS.

  6 and 7, a crankshaft 216 is supported on the upper frame 16 of the press 10 according to the present invention so as to be rotatable around an axis extending in the horizontal direction. As shown in FIG. 7, the crankshaft 216 is provided with a flywheel 218a that receives a driving rotational force from the electric motor 30a shown in FIGS. 1 and 7 through a clutch 218b that is well known in the art. . The press machine 10 is started by the rotation of the crankshaft 216 by the clutch-in of the clutch 218b.

  Referring to FIG. 1, a slide 20 that supports an upper mold 18b of a mold 18 is attached to the lower ends of a pair of rods 222 that pass through the lower end of the upper frame 16 so as to be movable in the vertical direction. As shown in FIG. 6, both rods 222 are power transmission devices that extend upward in parallel from both ends of the slide 20 and convert the rotational motion of the crankshaft 216 into a reciprocating motion in the vertical direction. The drive mechanism 230 reciprocates up and down. Thereby, the slide 20 is reciprocated up and down.

  As shown in FIGS. 6 and 7, the drive mechanism 230 is disposed so as to be reciprocally movable in the vertical direction on the upper frame 16 and pivotally connected to the connection link 232. A pair of connected first sliders 234, a pair of link mechanisms 236 that follow the reciprocating movement of the first sliders and bend and extend in synchronization with each other, and corresponding to each link mechanism 236, A pair of link mechanisms 238 that are bent and extended following the bending and extension movements of the corresponding link mechanisms 236, and a pair of second mechanisms that are disposed on the upper frame 16 so as to be vertically displaceable and are pivotally connected to both link mechanisms 236. And a position adjusting mechanism 242 for adjusting the position of the second slider 240 in the vertical direction.

  6 to 10, the connecting link 232 is connected to an eccentric portion of the crankshaft 216 and reciprocates in the vertical direction as the crankshaft 216 rotates. The first and second sliders 234 and 240 are received by a guide portion 244 formed on the upper frame 16 so as to be movable in the vertical direction. The first slider 234 reciprocates in the vertical direction following the reciprocating movement of the connecting link 232. The second slider 240 reciprocates in the vertical direction following the bending and stretching movements of both link mechanisms 236.

  As shown in FIGS. 6, 7 and 9, each link mechanism 236 includes a pair of links 236 a and 236 b connected to each other by a pivot 246 (see FIG. 9) so as to be bent. One link 236a of both link mechanisms 236 is connected to a connecting link 232 and a first slider 234 by a common pivot 248 so as to be rotatable about an axis extending in the horizontal direction, and the other link 236b is shown in FIG. As shown, a common pivot 250 is rotatably coupled to the second slider 240 about an axis that extends horizontally.

  In the illustrated example, the pivots 248 and 250 are provided so that their pivot points coincide with an axis 252 (see FIG. 6) extending in the vertical direction via the rotation center of the crankshaft 216.

  In the illustrated example, the link 236a of each link mechanism 236 is directly connected to both the connection link 232 and the first slider 234, but the link 236a of each link mechanism 236 is connected to the connection link 232 and the first slider. You may connect only to one of 234.

  As shown in FIGS. 6 and 9, each link mechanism 238 also includes a pair of links 238a and 238b that are connected to each other by a pivot 254 (see FIGS. 8 and 9) so as to be bent. One link 238a of each link mechanism 238 is connected to a bracket 256 attached to the upper frame 16 so as to be rotatable about an axis extending in the horizontal direction by a pivot 258, and the other link 238b is connected to the rod 222 by a pivot 260. It is rotatably connected around an axis extending in the horizontal direction.

  Each link mechanism 238 is pivotally connected to the corresponding link mechanism 236 by a pivot 254, a link 262, and a pivot 264 so as to bend and stretch following the bending and stretching of the corresponding link mechanism 236. In the illustrated example, the pivots 258 and 260 are provided so that their pivot points coincide with an axis 266 (see FIG. 6) extending in the vertical direction through the axis of the rod 222.

  In the illustrated example, each link mechanism 238 is connected to the link 236a. However, the link 262 may be connected to the link 236b, may be connected to both the links 236a and 236b, and the link 262 is used. Instead, the link mechanism 238 may be directly connected to the link mechanism 236, or one of the links 238a and 238b may be connected to the link mechanism 236.

  As shown in FIGS. 6 and 7, the position adjusting mechanism 242 includes a bifurcated bracket 270 pivotally connected to both links 236 b and both second sliders 240 by a pivot 250, and a male screw 272 extending downward from the bracket. And a worm wheel 274 that engages with the male screw, and a worm screw 276 that engages with the worm wheel. Instead of using the bracket 270, the male screw 272 may be pivotally connected to both the links 236 b and both the second sliders 240 by the pivot 250.

  The male screw 272 is connected to the bracket 270 so as not to rotate around the axis 252. The worm wheel 274 is supported by the support portions 278 and 280 of the upper frame 16 so as to be rotatable around the axis and not movable in the vertical direction. As shown in FIG. 10, the shaft portion of the worm screw 276 passes through the upper frame 16 in a rotatable manner, and includes a sprocket 282 at the end. The sprocket 282 is rotated by the adjusting servo motor 30b.

  When the sprocket 282 is rotated by the operation of the adjusting servo motor 30b, the worm screw 276 is rotated, the worm wheel 274 engaged with the worm screw 276 is rotated, and the male screw 272 screwed with the worm wheel 274 is moved upward or downward. Finally, the second slider 240 moves upward or downward.

  In the press 10, when the crankshaft 216 is rotated by the driving force from the electric motor 30a, the connecting link 232 is reciprocated in the vertical direction along with the rotation of the crankshaft 216. Accordingly, the first slider 234 is the same. Reciprocate in the direction. However, the second slider 240 does not move unless the worm wheel 274 is rotated. For this reason, the pivot 248 acts as a movable fulcrum of the link mechanism 236, and the pivot 250 acts as a fixed fulcrum of the link mechanism 236.

  The link 238a is connected to a bracket 256 fixed to the upper frame 16, while the link 238b is connected to a rod 222 that can move in the vertical direction. For this reason, the pivot 258 acts as a fixed fulcrum of the link mechanism 238, whereas the pivot 260 acts as a movable fulcrum of the link mechanism 238.

  Therefore, when the rotation of the flywheel 218a is transmitted to the crankshaft 216 by the clutch-in of the clutch 218b during the operation of the electric motor 30a, the connection link 232 and the first slider 234 reciprocate with the rotation of the crankshaft 216. Since it is moved, both link mechanisms 236 are bent and extended in synchronization. Thereby, both link mechanisms 238 are bent synchronously, and as a result, the slide 20 reciprocates up and down. From this, the link mechanism 238 acts as a knuckle mechanism or a toggle mechanism. The link mechanisms 236 and 238 function as a drive mechanism for the slide 20.

  When the second slider 240 moves upward, the bending angle of the link mechanism 236 decreases, and thereby the bending angle of the link mechanism 238 increases, so that the slide 20 is moved downward. On the other hand, when the second slider 240 moves downward, the bending angle of the link mechanism 236 increases, and thereby the bending angle of the link mechanism 238 decreases, so that the slide 20 is moved upward.

  When the second slider 240 moves upward or downward, since the position of the first slider 234 does not change in the vertical direction, the bending angle of the link mechanism 236 changes, but the bending / extension range does not move in the vertical direction. For this reason, the bottom dead center position and the stroke length of the slide 20 can be adjusted by rotating the sprocket 282. Therefore, the position adjusting mechanism 242 works as the bottom dead center position correcting mechanism 242 of the slide 20 together with the link mechanism 236 and the slider 40.

  The position adjusting mechanism, that is, the bottom dead center position correcting mechanism 242 is controlled in operation based on the output signal of the pressure detector 34.

  Referring again to FIG. 3, in the illustrated example, the pressure detector 34 is a strain gauge-like pressure inserted between the support 160a of the stationary gripper 124 and a fixed jaw 162 attached to the support. It consists of sensors. When the movable jaw 164 of the stationary gripper 124 is operated at a fixed stroke toward the fixed jaw 162, the pressure detector 34 receives an electric signal corresponding to the pressing force that the movable jaw 164 receives from the fixed jaw 162. To the arithmetic processing unit 36.

  Since the operation stroke of the movable jaw 164 is constant, as shown in FIG. 11, the pressing force represented by the electric signal has a thickness on the workpiece 28 sandwiched between the fixed jaw 162 and the movable jaw 164. Proportional to dimensions.

  The arithmetic processing unit 36 compares the electric signal with a reference value, and when the difference exceeds the allowable value, the arithmetic unit 36 causes the bottom dead center position correction mechanism 242 via the motor control circuit 38 so that the difference is within the allowable value. The servo motor 30b is operated. The bottom dead center position of the slide 20 is adjusted by the operation of the servo motor 30b.

  The bottom dead center position is adjusted based on real-time information from the pressure detector 34 provided in association with the stationary gripper 124. Accordingly, the bottom dead center position of the press machine 10 can be corrected quickly and appropriately in accordance with the change in the thickness dimension of the workpiece 28 supplied to the press machine 10, so that the operation of the press machine is appropriately performed. Can be controlled. Further, based on the output signal from the pressure detector 34, for example, when the plate thickness of the workpiece 28 exceeds a predetermined range, the operation of the press machine 10 can be stopped immediately. It is possible to prevent discharge of defective products due to changes in the plate thickness of the processed material 28. Further, instead of or in addition to stopping the operation of the press machine 10, an alarm is generated by sound or light when the thickness of the workpiece 28 exceeds a predetermined range in relation to the arithmetic processing unit 36. Can be provided.

  In the example shown in FIG. 3, the pressure detector 34 is provided between the fixed jaw 162 of the stationary gripper 124 that constitutes a part of the holding and conveying means and the support portion 160 a that supports the fixed jaw. For example, the pressure detector 34 can be provided on the surface of the fixed jaw 162 facing the movable jaw 164 or the surface of the movable jaw 164 facing the fixed jaw 162. Further, instead of the stationary gripper 124, the pressure detector 34 can be provided in the movable gripper 122 as in the above-described example. However, the illustrated example is desirable from the viewpoint of providing the pressure detector 34 in a stationary portion for simplification of the configuration.

  In addition, as shown in FIG. 12, the present invention can be applied to a roll feeder 126 including a pair of rolls 50 including a stationary roll 50a and a movable roll 50b. FIG. 12a shows the roll feeder 126 in the unclamped position, and FIG. 12b shows the roll feeder 126 in the clamped position.

  The movable roll 50b has a drive shaft 54a supported by a stationary support shaft 52a so as to convey the workpiece 28 in one direction. For example, the pressure detector 34 receives the drive shaft at a bearing portion that receives the drive shaft 54a. Is incorporated. The movable roll 50b has a driven shaft 54b supported by a support shaft 52b that can be moved up and down. The movable roll 50b is separated from the stationary roll 50a by a clamping position (FIG. 12b) close to the stationary roll 50a for conveying the workpiece 28. Repeated operation is possible between the unclamped position (FIG. 12a).

  The pressure detector 34 incorporated in the roll feeder 126 has a thickness dimension of the workpiece 28 sandwiched between the stationary roll 50a and the movable roll 50b, similarly to the gripper feeder 26, in the clamping position of FIG. 12a. Is output to the arithmetic processing unit 36. Therefore, based on the output signal of the pressure detector 34, the bottom dead center position of the slide 20 can be adjusted in real time as described above.

  Also in the roll feeder 126, the pressure detector 34 can be appropriately provided in relation to the bearing portion of the movable roll 50b or the support shaft 52b.

  If necessary, a detector for detecting the bottom dead center position (not shown) can be provided to detect the bottom dead center position of the slide 20, thereby enabling feedback control.

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention. Although an example of a press machine has been described as the processing machine, the present invention is not limited to this, and can be applied to various processing machines that handle the plate-shaped workpiece 28.

10 Press machine (processing machine)
12 Bolster 20 Slide 34 Pressure detector 36a Alarm 36a
50, 26 Feeder 50a, 50b, 122, 124 Nipping and conveying means (roller, movable gripper, stationary gripper)
112 Feeder frame 128 Sliding block 132, 162 Fixed jaw 134, 164 Movable jaw 242 Bottom dead center position correction mechanism

Claims (9)

A feeder comprising: a frame; and a sandwiching and conveying unit supported by the frame and sandwiching and conveying the workpiece to continuously supply a plate-like workpiece to a processing machine, the sandwiching and conveying unit Is provided with a pressure detector that outputs a signal corresponding to a pressure that varies according to the thickness of the workpiece when the means is operated to clamp the workpiece .
The feeder includes a movable gripper in which the holding and conveying means reciprocates along the conveyance path of the workpiece, and operates to clamp and release the workpiece in synchronization with the reciprocating movement, and the movable gripper Is a gripper feeder that includes a stationary gripper that operates in synchronization with the operation of the movable gripper to clamp the workpiece when the workpiece is clamped, and one of the movable gripper and the stationary gripper The pressure detector is provided on one side,
The movable gripper includes a sliding block supported by the frame to reciprocate along the conveyance path, a fixed jaw statically supported by the sliding block, and the covered jaw in cooperation with the fixed jaw. A movable jaw that operates at a predetermined stroke to sandwich and release the workpiece, and the stationary gripper includes a fixed jaw that is statically supported by the frame, and the workpiece in cooperation with the fixed jaw. A movable jaw that operates with a predetermined stroke to be clamped and released, between the fixed jaw of the movable gripper and the sliding block that supports the fixed jaw, or the fixed jaw and the fixed of the stationary gripper either one of between the frame supporting the jaws, characterized in that the pressure detector is arranged to receive a pressing force from the corresponding said movable jaw Ida.   The feeder according to claim 1, wherein the operation of the processing machine is controlled by an output signal from the pressure detector.   The feeder according to claim 1, further comprising an alarm device that issues an alarm when an output signal of the pressure detector exceeds a predetermined range.   The feeder according to claim 2, wherein the processing machine is a press machine that is controlled in operation based on a comparison between a preset pressure value and a pressure measurement value corresponding to an output signal from the pressure detector. The press machine has a bottom dead center position correction mechanism that corrects a bottom dead center position of a slide that reciprocates vertically on a bolster, and the bottom dead center position correction is performed by measuring the pressure measured value by the pressure detector. The feeder according to claim 4 , wherein a bottom dead center position is corrected so that the pressure measurement value is within a predetermined range when the pressure exceeds a predetermined value range. A press machine provided with the feeder according to claim 1 ,
The feeder includes a frame, and a nipping and conveying unit that is supported by the frame and sandwiches and conveys the workpiece so as to continuously supply the plate-like workpiece to a processing machine. Is provided with a pressure detector that outputs a signal corresponding to a pressure that changes according to the thickness of the workpiece when the clamping and conveying means is operated to clamp the workpiece. A press machine that receives an operation control based on an output signal of the pressure detector. The press according to claim 6 , wherein the operation is controlled based on a comparison between a preset pressure value and a pressure measurement value corresponding to an output signal from the pressure detector. The press machine has a bottom dead center position correction mechanism that corrects the bottom dead center position of a slide that reciprocates in the vertical direction on the bolster, and the bottom dead center position correction is performed by measuring a pressure value measured by the pressure detector. The press machine according to claim 7 , wherein a bottom dead center position is corrected so that the pressure measurement value is within a predetermined range when a predetermined value range is exceeded. The press machine according to claim 8 , wherein the feeder includes an alarm device, and the alarm device issues an alarm when a pressure measurement value by the pressure detector exceeds a predetermined value range.

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