JP2015167985A - Transfer device of heading machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transfer device of a heading machine which can exactly determine a grip error of a workpiece, can be applied to a constitution which reversely transfers the workpiece, and can reduce a risk of the damage of a die and a punch while avoiding the two-punch of the workpiece.SOLUTION: A transfer device of a heading machine comprises a transfer base part 2 arranged at a transfer route of a workpiece, a fin pair 3 arranged at the transfer base part 2, a finger drive part 4 which drives the switching operation of the finger pair 3, and a transfer drive part 5 which moves the finger pair 3 to a downstream side from an upstream side of the transfer route by driving the transfer base part 2, and returns it to the upstream side from the downstream side. The transfer device further comprises a finger drive detection part 6 which detects a drive state of a grip lever 42 (specified drive member) constituting the finger drive part 4, and a grip error determination part 8 which determines a grip error that the finger pair 3 has failed in gripping the workpiece W on the basis of the drive state of the grip lever 42 which is detected when the transfer base part 2 is in a specified state.

Description

  The present invention relates to a transfer device that is provided in a forging machine for forging and forming a workpiece by a die and a punch and conveys the workpiece from an upstream side to a downstream side.

  2. Description of the Related Art A forging machine for producing a part having a predetermined shape by forging a workpiece is known. In a forging machine, a structure is widely used in which a die and a punch are arranged opposite to each other on an axis to perform forging forming, and a transfer device conveys a workpiece from the upstream side to the downstream side. A multi-process forging machine that forms a forging process by a plurality of sets of dies and punches and processes a workpiece in stages has also become common. Furthermore, a reversing transfer device that reverses the front-rear direction of the work and conveys it to the downstream process is used for processing both the front and rear sides of the work. Technical examples of this type of inverting transfer device are disclosed in Patent Document 1 and Patent Document 2.

  The work reversal installation mechanism disclosed in Patent Document 1 includes a finger expansion / contraction / gripping actuator for moving the finger toward and away from the work and further gripping, a pickup actuator for driving the finger up and down, and a finger. A transfer stage is used for transferring to a stage processing station (downstream process) and returning it. As a result, high-value-added transfer press processing that can be reversed and placed in multiple stages with a small number of actuators is realized in the manufacture of minute products on the order of millimeters.

  The transfer device of a forging machine disclosed by the applicant of the present invention in Patent Document 2 is to transfer a workpiece to a downstream process by a 180 ° revolution of a chuck (finger pair). This transfer device is configured to change the setting of whether or not the chuck rotates and to switch the work inversion and non-inversion. In addition, this transfer device employs a system in which a main drive source that drives the punch is used in common, and the drive characteristics are set by a cam mechanism.

  Here, regardless of whether or not the workpiece is reversed, in general, in a forging machine, if a pinching mistake that fails to pinch the workpiece with a pair of fingers occurs, the die or punch may be damaged. In other words, if a clamping error occurs in a certain process and the workpiece remains in the die, the second workpiece is loaded in the next machining cycle, and the punch strikes two punches that stack and press the two workpieces. will have to go. As a result, excessive stress is generated in the dies and punches as compared with the normal time, resulting in damage, and large losses such as restoration costs for damaged parts and delays in the production of workpieces occur.

  In order to avoid breakage of dies and punches, Patent Document 3 discloses an example of technology for detecting a finger pair pinching error. The transfer chuck grip detection device of Patent Document 3 is provided when a strain gauge is provided around a support portion that supports an intermediate portion of a cam arm that drives a chuck unit, and is detected when an open / close chuck (finger pair) is gripping a material. Grasping abnormality is determined based on the presence or absence of distortion. According to this, since the strain gauge is attached to the fixed structure, the reliability of wiring and the like is high, re-attachment is not required when the opening / closing chuck is replaced, and the possibility of malfunction is low. Further, as a conventional technique, a technique for providing a contact sensor on an opening / closing chuck and a technique for detecting a pinching error by attaching a micro switch to a transfer drive unit are described.

JP 2013-180297 A JP 2011-121733 A Utility Model Registration No. 3153881

  By the way, in patent document 3, if the strain gauge provided in the intermediate part of the cam arm does not detect the strain, it is determined as a normal state, and when the strain is detected, it is determined that the grip is abnormal. However, even when the cam arm starts to move even in a normal state, a distortion may temporarily occur. Therefore, it is not always possible to reliably detect a finger pair pinching error without error.

  Furthermore, when the pinching error detection technique exemplified in Patent Document 3 is applied to the inversion type transfer device exemplified in Patent Documents 1 and 2, problems inherent to the inversion type occur. In detail, in a general transfer device that does not reverse the workpiece, the finger pair simply translates between the upstream side and the downstream side, whereas in the reverse transfer device, the rotation and rotation of the finger pair are performed. Since this is done, the conveying operation becomes complicated. Even in the finger driving unit that opens and closes the finger pair, some members rotate. For this reason, the arrangement | positioning position of the sensor which can detect reliably the clamping mistake of a finger pair is restricted. Furthermore, it is difficult to set a determination reference value for determining a detection timing by the sensor and a pinching error.

  Further, the technique of Patent Document 3 does not disclose a specific means for avoiding double-working of a workpiece even though a means for detecting a pinching error is disclosed. In a general forging machine, the punch is driven from a main drive source such as a motor via a main drive shaft, and the transfer device is often driven in common by a cam mechanism connected to the main drive shaft. For this reason, even if the brake or clutch of the main drive shaft is controlled to stop when a holding error is detected by the transfer device, there is a possibility that double strokes cannot be avoided due to inertial operation or control time delay.

  The present invention has been made in view of the above-mentioned problems of the background art, can reliably determine a workpiece clamping error, can be applied to a configuration in which a workpiece is reversed and conveyed, and further avoids double-working of the workpiece. An object to be solved is to provide a transfer device for a forging machine that can reduce the risk of breakage of a die or a punch.

  The transfer device of the forging machine according to the present invention includes a transfer base disposed in a conveyance path for conveying the workpiece of the forging machine that performs forging forming processing by pressing the workpiece with a die and a punch, and is provided on the transfer base and is opened and closed. A finger pair that operates to pinch and open the workpiece, a finger drive unit that drives an opening and closing operation of the finger pair, and a drive base that drives the finger pair that clamps the workpiece to the upstream side of the transport path A transfer drive unit of a forging machine that moves from the downstream side to the upstream side and moves the finger pair that has opened the workpiece from the downstream side to the upstream side, and is a part of the finger drive unit A finger drive detector for detecting the drive state of the specific drive member and the transfer base when the transfer base is in a specific state. Based on the drive state of the particular drive member, said pairs of fingers is further provided with a determining clamping miss judgment unit clamping misses failed to sandwich the workpiece.

  Further, the transfer drive unit rotates the transfer base, the specific drive member rotates in conjunction with the transfer base, and the pinching error determination unit detects when the transfer base is at a specific rotation angle. The pinching error may be determined based on the driven state of the specific drive member.

  Further, the pinching error determination unit has a rotation angle at a rotation angle before the transfer base starts to rotate and the finger pair is on the upstream side, and a rotation angle after the transfer base starts to rotate. Then, it is preferable to determine the pinching mistake when the finger pair is in the middle of moving from the upstream side to the downstream side.

  In addition to a main drive source for driving the punch and the finger drive unit, the punch further includes a high-speed auxiliary drive source that drives the finger pair to open at high speed, and the pinching error determination unit is configured to determine whether the pinching error has occurred. In addition, the high-speed auxiliary drive source may be controlled to open the finger pair to forcibly drop the workpiece.

  Furthermore, the main drive source may be a motor, and the high-speed auxiliary drive source may include either a compressed air drive mechanism, a hydraulic drive mechanism, or an electric actuator.

  The transfer device for a forging machine according to the present invention is based on a finger drive detection unit that detects a drive state of a specific drive member of a finger drive unit, and a drive state of the specific drive member that is detected when the transfer base is in a specific state. A clamping error determination unit that determines a clamping error. Here, since a holding error is determined only when the transfer base is in a specific state, even when the driving state of the specific drive member changes with time, the determination timing can be aligned every time, and the workpiece is held. You can reliably determine mistakes.

  Furthermore, the transfer base and the specific drive member rotate, and the pinching error determination unit can be configured to determine a pinching error based on the driving state of the specific drive member detected when the transfer base is at a specific rotation angle. . According to this, the present invention can also be applied to a configuration in which the transfer base is rotated and the workpiece is reversed and conveyed, and determination is performed by detecting each time at a specific rotation angle of the transfer base. Accordingly, it becomes easy to set the determination reference value for determining the detection timing of the finger drive detection unit and the clamping error, and it is possible to reliably determine the workpiece clamping error.

  Furthermore, the pinching error determination unit can determine two pinching errors before the transfer base within one machining cycle starts rotating and after the rotation starts. That is, the first determination can be performed when the finger pair holds the workpiece on the upstream side, and the second determination can be performed while the workpiece is being conveyed. The first determination is effective when the workpiece falls on the upstream side. The second determination is effective when the workpiece remains on the die due to sticking or the like on the upstream side, and the finger pair cannot be transported even once the workpiece is sandwiched. By performing the determination twice in one machining cycle, the accuracy of determining a workpiece clamping error is improved.

  In addition to the main drive source, it also has a high-speed auxiliary drive source that drives the finger pair to open at high speed. The pinching error determination unit opens the finger pair and forcibly drops the workpiece when a pinching error is detected. You can make it. According to this, even if a clamping error occurs due to the fixing of the workpiece, and the workpiece that has already been pressed remains in the die, the next workpiece falls and is not carried in. And the possibility of breakage of the punch can be reduced.

  Further, the main drive source is a motor, and the high-speed auxiliary drive source can be configured to include either a compressed air drive mechanism, a hydraulic drive mechanism, or an electric actuator. According to this, since the drive speed performance of the high-speed auxiliary drive source can be set appropriately in accordance with the machining speed at which the main drive source drives the punch, the above-mentioned workpiece dropping can be reliably performed before the punch hitting pressure. Done. Therefore, it is possible to reliably avoid the two-piece work.

It is a top view of the forging machine equipped with the transfer apparatus of the embodiment of the present invention. It is a top view which shows the transfer apparatus of embodiment. FIG. 3 is a partial cross-sectional side view of the transfer device according to the embodiment, viewed from the right in FIG. 2. It is a top view explaining the shape of the grip lever corresponded to a specific drive member. It is a top view explaining the structure of a finger drive detection part. It is the figure which showed the operation | movement timing in the processing cycle of the forging machine equipped with the transfer apparatus of embodiment.

  Embodiments for carrying out the present invention will be described with reference to FIGS. FIG. 1 is a plan view of a forging machine 9 equipped with a transfer device 1 according to an embodiment of the present invention. The forging machine 9 includes a plurality of sets of opposing dies 93 and punches 96, and is a multi-step forging machine that sequentially performs a plurality of forging forming processes on a workpiece. The forging machine 9 further includes a base 91, a die block 92, a ram 94, a punch block 95, a main drive source 97, and the like.

  The base 91 is a housing for disposing each part, and is firmly formed. The die block 92 is attached to the base 91 in a replaceable manner. The plurality of dies 93 are replaceably attached to the front (left side in the figure) of the die block 92, and a predetermined processing die is formed on the front side facing the left direction in the figure. The ram 94 is held so as to be able to reciprocate in the longitudinal direction (left-right direction in the figure) with respect to the base 91. The punch block 95 is replaceably attached to the front of the ram 94 (on the right side in the drawing). The plurality of punches 96 are attached to the front of the punch block 95 (on the right side in the drawing) in a replaceable manner, and a predetermined working die is formed on the front side facing the right direction in the drawing. The upper side of the drawing in FIG. 1 is the upstream first step, and the lower side of the drawing is the fifth downstream step. In the present embodiment, the first to fifth steps are constituted by five sets of dies 93 and punches 96, but the present invention can be implemented without depending on the number of steps.

  The forging machine 9 includes a wire cutting and feeding device omitted in FIG. The wire cutting and supplying apparatus cuts and supplies a workpiece having a predetermined length from a long wire. The transfer device 1 according to the embodiment is disposed from above the die block 92 to the front of the die 93. The transfer device 1 is a reversing transfer device that transports a workpiece by reversing or non-reversing a workpiece from an upstream process to a downstream process. The transfer device 1 includes a plurality of sets of transfer cassettes 11 arranged between the processes. The most upstream transfer cassette 11 conveys the workpiece from the wire cutting and supplying apparatus to the first step without being reversed. In addition, the second and subsequent transfer cassettes 11 convey the work in reverse or non-reverse in order from the first process to the fifth process. In addition, the forging machine 9 includes a kickout device and a trimming device (not shown).

  A main drive source 97 is provided to reciprocate the ram 94. The main drive source 97 can be, for example, an induction motor or a synchronous motor that operates with a three-phase AC power source. The main drive source 97 is also commonly used for driving the transfer device 1, the wire cutting and feeding device, the kickout device, and the trimming device. The driving force of the main drive source 97 is input to the crankshaft 9 </ b> A that drives the ram 94 via the flywheel 98 and the speed reduction mechanism 99. Further, the driving force is branched and transmitted from the crankshaft 9A to the side shaft 9C via the branch gear pair 9B.

  A transfer cam 9D is provided on the side shaft 9C so as to rotate integrally. As will be described later in detail, the transfer cam 9 </ b> D drives the rack gear 52 to reciprocate to rotationally drive the transfer base 2 of the transfer device 1. Further, the same number of open / close cams 9F as the transfer cassette 11 are connected to be rotated from the side shaft 9C via the transfer drive 9E. The open close cams 9F are arranged at equal intervals in the width direction, and correspond to positions between the processes. Each open / close cam 9F drives the finger drive unit 4 of each transfer cassette 11 respectively.

  Further, a cutter cam 9G is provided on the side shaft 9C, and a pusher cam 9H, a feed cam 9J, a feed roller 9K, the same number of kick-out cams 9L as the dies 93, and a trimming cam 9M are connected. About these cams, since the relevance with the transfer apparatus 1 is low, description is abbreviate | omitted.

  FIG. 2 is a plan view illustrating the transfer device 1 according to the embodiment. FIG. 2 shows the transfer cassette 11 for three steps. The left side of FIG. 2 is the upstream side process, and the right side is the downstream side process. For convenience, the first, second, and third transfer cassettes 111, 112, and 113 are called in order from the left side. FIG. 3 is a partial cross-sectional side view of the transfer device 1 according to the embodiment, as viewed from the right side of FIG. The transfer device 1 includes a transfer base 2, a finger pair 3, a finger drive unit 4, a transfer drive unit 5, a finger drive detection unit 6, and an open cylinder 7 for each transfer cassette 11, and a plurality of sets of clamping error determination units 8. The transfer cassette 11 is provided in common. In FIG. 3, the finger pair 3 is shown in a posture rotated by 90 ° from the state of FIG.

  As shown in FIG. 3, the transfer base 2 is formed in a substantially cylindrical shape by combining a plurality of members. The transfer base 2 is supported on the base 91 by two sets of upper and lower bearings 21 and 22. A sector gear 51 is engraved on the side surface of the transfer base portion 2 between the bearing portions 21 and 22 slightly on the side. A rack gear 52 is provided on the base 91 so as to mesh with the sector gear 51. The rack gear 52 is driven to reciprocate in the front and back direction in FIG. 3 by the transfer cam 9D described above. As a result, the transfer base 2 is driven to rotate 180 ° about the rotation axis AR extending in the vertical direction, and reciprocates by revolving the finger pair 3 between the upstream process and the downstream process. For example, in FIG. 2, the first transfer cassette 111 drives the finger pair 3 to reciprocate between a position P1 corresponding to the upstream process and a position P2 corresponding to the downstream process.

  A finger support portion 23 projects from the side surface of the transfer base portion 2 in the direction opposite to the sector gear 51. A cylindrical body 24 extending vertically is fixed to the tip of the finger support portion 23. A finger support cylinder 25 is fitted inside the cylinder body 24 so as to be relatively rotatable. A finger support member 26 is provided at a lower portion of the finger support cylinder 25 that extends downward from the cylindrical body 24. The finger support member 26 supports the two fingers 31 constituting the finger pair 3 in a swingable manner.

  As shown in FIG. 2, each transfer cassette 11 is provided with a reversal setting unit 53. When the reverse setting part 53 of the adjacent transfer cassette 11 is connected using the connecting plate 54, the finger support cylinder 25 and the finger pair 3 move in parallel with the revolution movement. The first transfer cassette 111 and the second transfer cassette 112 are connected to the inversion setting portion 53 by a connecting plate 54 and convey the workpiece W in a non-inverted manner. If the reversal setting unit 53 is not connected, the finger support cylinder 25 and the finger pair 3 rotate along with the revolution movement. Thereby, the third transfer cassette 113 reverses and conveys the workpiece W.

  The details of the configuration for switching between inversion and non-inversion of the workpiece using the inversion setting unit 53 and the connecting plate 54 have been disclosed in Patent Document 2. As will be understood from the above description, the sector gear 51, the rack gear 52, the reversal setting unit 53, the connecting plate 54, and the like constitute the transfer drive unit 5 that conveys the workpiece W while reversing or non-reversing.

  The two fingers 31 are generally symmetrical with each other when viewed from the front, and have a shape bent at two locations. Each finger 31 has a driven point 32 at the upper end, a clamping point 33 at the lower end, and a swing fulcrum 34 at the upper bent position. The swing fulcrum 34 is supported by the finger support member 26. When the driven point 32 is driven downward, the two fingers 31 swing around the swing fulcrum 34, the clamping point 33 closes and the workpiece W is clamped. When the driven point 32 is driven upward, the two fingers 31 swing in the opposite directions around the swinging fulcrum 34, and the clamping point 33 is opened to release the workpiece W.

  The finger drive unit 4 includes a finger opening / closing rod 41, a grip lever 42, a drive lever 43, and the like. The finger opening / closing rod 41 is disposed inside the finger support cylinder 25 so as to be movable up and down. An engaging protrusion 411 provided at the lower end of the finger opening / closing rod 41 is formed so as to engage with the driven point 32 of the two fingers 31 and drive up and down. Near the upper portion of the finger opening / closing rod 41, two flange portions 412 and 413 are provided which are spaced apart vertically and expand horizontally in a flange shape.

  The grip lever 42 is disposed on the upper part of the transfer base 2. The grip lever 42 corresponds to the specific drive member of the present invention that constitutes the finger drive unit 4 and rotates in conjunction with the transfer base 2. FIG. 4 is a plan view for explaining the shape of the grip lever 42 corresponding to the specific drive member. The grip lever 42 includes a supported portion 421, a driven arm 422, two driving arms 424, 425, and the like.

  The supported portion 421 is supported so as to be swingable by a support pin 27 penetrating from the rotation base AR of the transfer base portion 2. A wide driven arm 422 extends in a direction from the supported portion 421 toward the rotation axis AR. The position of the rotation axis AR of the driven arm 422 is a depressed portion 423 that is depressed. Two narrow driving arms 424 and 425 extend from the supported portion 421 in a direction opposite to the driven arm 422 in parallel with each other. The two drive arms 424 and 425 respectively have horizontal cylindrical elevating drive members 426 and 427 inside facing each other. The raising / lowering drive members 426 and 427 are disposed between the flange portions 412 and 413 of the finger opening and closing rod 41.

  The drive lever 43 is supported by a base 91 so that a supported part formed in the middle of the length direction can swing. The lower part of the tip of the drive lever 43 is a pressing part 431, and the upper part of the tip is a pressing force part 432. The push-down portion 431 is formed and arranged so as to engage with the pushed-down portion 423 of the grip lever 42 and push it down. The forced push-down portion 432 is formed so as to be forced down at a high speed by a piston member 72 of the open cylinder 7 described later. The base end on the right side of FIG. 3 of the drive lever 43 is driven up and down by the open close cam 9F described above. Along with this, the push-down portion 431 is driven to descend and ascend. The biasing spring 44 is disposed above the finger opening / closing rod 41. The biasing spring 44 biases the flange portion 412 downward.

  When the push-down portion 431 of the drive lever 43 is raised, the grip lever 42 swings counterclockwise in FIG. 3, and the elevating drive members 426 and 427 are lowered. Accordingly, the finger opening / closing rod 41 is in the lowered position, and the finger pair 3 holds the workpiece W therebetween. When the push-down portion 431 of the drive lever 43 is driven downward, the pushed-down portion 423 of the grip lever 42 is pushed down. The grip lever 42 swings clockwise in FIG. 3, and the lifting drive members 426 and 427 are raised. As a result, the finger opening / closing rod 41 is driven upward, and the finger pair 3 opens the workpiece W.

  The finger drive detection unit 6 includes an attack piece 61, a detection plate 62, a proximity sensor 63, and the like. FIG. 5 is a plan view illustrating the configuration of the finger drive detection unit 6. FIG. 5 illustrates the finger drive detection unit 6 of the second transfer cassette 112 and the third transfer cassette 113. The finger drive detection unit 6 of the first transfer cassette 111 is configured in a mirror-symmetric shape with the left and right sides of FIG. 5 reversed. As shown in FIG. 4, the attack piece 61 is provided at the center in the width direction near the tip of the driven arm 422 of the grip lever 42. The attack piece 61 protrudes upward in a hemispherical shape.

  The detection plate 62 detects the height position of the rotating attack piece 61 and transmits it to the proximity switch 63 disposed on the base 91. The detection plate 62 is formed by integrally connecting a detection plate 621, a transmission shaft 624, and a transmission plate 625. As shown in FIG. 5, the detection plate 621 has a shape in which a horseshoe-shaped portion 622 and a rectangular portion 623 are connected. The horseshoe-shaped portion 622 is disposed on the upper side of the attack piece 61. While the transfer base 2 is rotated by 180 °, the attack piece 61 rotates while drawing a semicircular locus 61T (shown in FIG. 5) while being in contact with the lower surface of the horseshoe-shaped portion 622 of the detection plate 62. One side of the rectangular portion 623 away from the horseshoe-shaped portion 622 is fixed to the transmission shaft 624.

  The transmission shaft 624 is swingably supported by two support portions 9N and 9P provided on the base 91. The detection plate 621 described above is fixed at a position between the two support portions 9N and 9P of the transmission shaft 624. A transmission plate 625 is fixed to a position outside the support portion 9N of the transmission shaft 624 (left side in FIG. 5). The transmission plate 625 is a band plate-like member and extends in the reverse direction of the detection plate 621. A sensor facing plate 626 is provided on the upper portion of the distal end of the transmission plate 625 away from the transmission shaft 624.

  As shown in FIG. 3, the proximity sensor 63 is disposed above the sensor facing plate 626. The proximity sensor 63 is fixed to a sensor base 9Q provided upright on the base 91 and faces downward. The proximity sensor 63 detects the distance D from the sensor facing plate 626 and sends the detection signal Sd to the pinching error determination unit 8.

  When the driven arm 422 of the grip lever 42 is raised, the attack piece 61 pushes up the horseshoe-shaped portion 622 of the detection plate 62. As a result, the detection plate 62 swings about the transmission shaft 624 in the clockwise direction in FIG. 3, and the sensor facing plate 626 descends to increase the distance D. Therefore, the proximity sensor 63 can detect a driving state in which the grip lever 42 swings.

  The open cylinder 7 corresponds to the high-speed auxiliary drive source of the present invention, and is disposed above the forced push-down portion 432 of the drive lever 43. The open cylinder 7 includes a cylinder member 71 and a piston member 72 that is accommodated in the cylinder member 71 and can protrude downward. The open cylinder 7 is driven by a compressed air drive mechanism (not shown). The compressed air drive mechanism is common to all the transfer cassettes 11. The compressed air drive mechanism operates in response to a command signal Sc from the pinching error determination unit 8 to send compressed air into the cylinder member 71 and drive the piston member 72 downward. Thereby, the piston member 72 forcibly depresses the forced depressing portion 432 of the drive lever 43 at a high speed regardless of the operation of the open close cam 9L.

  The pinching error determination unit 8 is configured using an electronic control device that incorporates a CPU and operates by software. The sandwiching error determination unit 8 receives the detection signal Sd from the proximity sensor 63 and converts it into a distance D. Further, the clamping error determination unit 8 receives information on the rotation angle θ of the crankshaft 9A from a rotation angle sensor (not shown). The clamping error determination unit 8 determines a clamping error of the finger pair 3 based on the distance D (details will be described later). The pinching error determination unit 8 transmits a command signal Sc to the compressed air drive mechanism when a pinching error is determined.

  Next, the operation of the forging machine 9 will be described. FIG. 6 is a diagram illustrating the operation timing in the machining cycle of the forging machine 9 equipped with the transfer device 1 of the embodiment. In FIG. 6, the horizontal axis represents the rotation angle θ of the crankshaft 9A, and the range of the rotation angle θ = 0 ° to 360 ° corresponds to one machining cycle. The four characteristic curves shown in FIG. 6 are, in order from the top, the stroke characteristic St of the crankshaft 9A, the kickout characteristic Ko of the kickout device, the operating characteristic Mv of the transfer drive unit 5, and the opening / closing characteristic Fm of the finger pair 3. Represents.

  According to the stroke characteristic St shown in FIG. 6, the punch 96 is farthest from the die 93 at the rear dead center of the rotation angle θ = 0 ° and the rotation angle θ = 360 °. Further, at the front dead center at the rotation angle θ = 180 °, the punch 96 comes closest to the die 93 and hits the workpiece. The kickout characteristic Ko of the kickout device is set by the kickout cam 9L described above. According to the kick-out characteristic Ko, the kick-out device starts to move from the return position near the rotation angle θ = 255 ° and starts to push the pressed workpiece from the die 93, and reaches the extrusion position near the rotation angle θ = 355 °. End the workpiece extrusion. Further, it starts to move from the pushing position around the rotation angle θ = 5 °, and returns to the return position around the rotation angle θ = 120 °.

  The operating characteristic Mv of the transfer drive unit 5 is set by the transfer cam 9D described above. According to the operation characteristic Mv, the transfer driving unit 5 starts to rotate the transfer base 2 around the rotation angle θ = 5 °, and starts to revolve the finger pair 3 holding the workpiece in the upstream process. The transfer drive unit 5 finishes moving the workpiece and the finger pair 3 to the downstream process at a rotation angle θ of around 80 °. Furthermore, the transfer driving unit 5 starts to rotate the transfer base 2 around the rotation angle θ = 230 °, and starts to revolve the finger pair 3 positioned in the downstream process. The transfer driving unit 5 finishes returning the finger pair 3 to the upstream process at a rotation angle of about θ = 305 °.

  The open / close characteristic Fm of the finger pair 3 is set by the above-described open / close cam 9F. According to the opening / closing characteristic Fm, the finger pair 3 starts to open in the downstream process at the rotation angle θ = 150 °, and finishes opening the workpiece at the front dead center at the rotation angle θ = 180 °. Further, the finger pair 3 starts to close in the upstream process at the rotation angle θ = 270 °, and finishes clamping the workpiece pushed out at the rotation angle θ = 300 °. The open / close characteristic Fm of the finger pair 3 can be changed to a range indicated by a broken line in FIG. 6 according to the shape of the workpiece.

  Next, the operation and action of the transfer device 1 of the embodiment will be described. As described above, when the transfer driving unit 5 rotationally drives the transfer base 2 to revolve the finger pair 3, the contact point at which the attack piece 61 contacts the detection plate 62 has a semicircular locus 61T (shown in FIG. 5). Draw and move. At this time, the distance between the contact point and the transmission shaft 624 changes. For this reason, even if the height position of the attack piece 61 is constant, when it rotates in conjunction with the transfer base 2, the detection plate 62 slightly swings and the tilt angle changes slightly. Thereby, the distance D between the proximity sensor 63 and the sensor facing plate 626 can change. This becomes an error factor when the pinching error determination unit 8 determines a pinching error of the finger pair 3 based on the distance D.

  Therefore, in order to eliminate this error factor, the clamping error determination unit 8 determines a clamping error based on the distance D detected by the proximity sensor 63 when the transfer base 2 is at a specific rotation angle. Specifically, as the specific rotation angles of the transfer base 2, two rotation angles θ1 = 355 ° and rotation angle θ2 = 17.5 ° of the crankshaft 9A shown in FIG. 6 are set as detection timings.

  At the rotation angle θ1 = 355 °, the transfer base 2 is at the rotation angle before starting to rotate, and the finger pair 3 is in the upstream process. At this timing, the finger pair 3 already holds the workpiece pushed out in the upstream process. In this case, if the workpiece falls, a pinching error occurs. Further, at the rotation angle θ2 = 17.5 °, the transfer base 2 is at the rotation angle after starting to rotate, and the finger pair 3 revolves from the upstream process to the downstream process to convey the sandwiched workpiece. On the way. In this case, if the workpiece stays on the die 93 due to sticking or the like, the finger pair 3 cannot be transported even once the workpiece is sandwiched, and a pinching error occurs.

  The clamping error determination unit 8 holds a determination reference value D1 and a determination reference value D2 regarding the distance D for each of the rotation angle θ1 = 355 ° and the rotation angle θ2 = 17.5 °. The determination reference values D1 and D2 are set in advance based on the distance D when the finger pair 3 normally holds the workpiece W. If the finger pair 3 does not clamp the workpiece W, the clamping points 33 of the fingers 31 come into contact with each other, and the finger opening / closing rod 41 is lowered than normal. Then, the grip lever 42 swings counterclockwise in FIG. 3 than normal, and the detection plate 62 swings clockwise in FIG. 3 than normal. Thereby, the detected distance D becomes excessive and exceeds the determination reference values D1 and D2. Therefore, the pinching error determination unit 8 can determine a pinching error in which the finger pair 3 has failed to pinch the workpiece W.

  The clamping error determination unit 8 transmits a command signal Sc to the compressed air drive mechanism when a clamping error is determined in any of the finger pairs 3 of the plurality of sets of transfer cassettes 11. Then, the compressed air drive mechanism drives the piston members 72 of the open cylinders 7 of all the transfer cassettes 11 downward. The forced pressing portion 43 of the drive lever 43 is forcedly pressed down at a high speed. As a result, each finger opening / closing rod 41 is driven upward, and each finger pair 3 opens the workpiece regardless of the current revolution position. Therefore, even if a pinching error occurs in a certain process and a pressed workpiece remains on the die 93, the next workpiece falls and is not carried in.

  In the transfer device 1 of the forging machine 9 according to the embodiment, the finger drive detection unit 6 that detects the drive state of the grip lever 42 that rotates together with the transfer base 2 in the finger drive unit 4 and the transfer base 2 are in a specific state. A clamping error determination unit 8 that determines a clamping error based on the detected driving state of the grip lever 42. Here, the clamping error determination unit 8 determines a clamping error only when the transfer base 2 has a specific rotation angle. Therefore, even if the interval D, which is the detected value of the driving state of the attack piece 61 provided on the grip lever 42, changes depending on the rotation angle, the determination timing can be aligned every time, and a workpiece clamping error can be ensured. Can be determined.

  Furthermore, the embodiment is applied to a configuration in which the transfer base 2 is rotated and the work is reversed and conveyed, and determination is performed by detecting each time at a specific rotation angle of the transfer base 2. Accordingly, the detection timing (rotation angles θ1, θ2) of the finger drive detection unit 6 and the determination reference values D1 and D2 for determining the clamping error can be easily set, and the workpiece clamping error can be reliably determined.

  Further, the pinching error determination unit 8 determines two pinching errors before the transfer base 2 within one machining cycle starts rotating (rotation angle θ1) and after it starts rotating (rotation angle θ2). That is, the first determination is performed when the finger pair 3 clamps the workpiece in the upstream process, and the second determination is performed while the workpiece is being conveyed. The first determination is effective when the workpiece falls in the upstream process. The second determination is effective when the workpiece remains on the die 93 due to sticking or the like in the upstream process, and the finger pair 3 cannot be conveyed even once the workpiece is sandwiched. By performing the determination twice in one machining cycle, the accuracy of determining a workpiece clamping error is improved.

  Further, in addition to the main drive source 97, an open cylinder 7 that drives the finger pairs 3 to open at high speed is further provided. The clamping error determination unit 8 opens all the finger pairs 3 when a determination of a clamping error occurs. Force to fall. According to this, even if a clamping error occurs due to the fixing of the workpiece and the workpiece that has already been pressed remains in the die 93, the next workpiece falls and is not carried in. The risk of damage to the die 93 and the punch 96 can be reduced.

  Further, the main drive source 97 is a motor, and the open cylinder 7 is driven by a compressed air drive mechanism. According to this, the drive speed performance of the open cylinder 7 can be set appropriately in accordance with the machining speed at which the main drive source 97 drives the punch 96, so that the next work drop described above occurs before the punch 96 hitting pressure. Surely done. Therefore, it is possible to reliably avoid the two-piece work.

  In addition, although the transfer apparatus 1 of embodiment is arrange | positioned in the multi-process forging machine and enables the reversal conveyance of a workpiece | work, this invention is not limited to this. In other words, the present invention can also be applied to the use of loading and unloading a workpiece with a single-process forging machine having a pair of dies and punches, and also to the application of transferring the workpiece in a non-reversed manner when the transfer base moves in parallel. it can.

  Furthermore, in the embodiment, the structure of the finger drive detection unit 6 can be modified as appropriate, and the detection timing (rotation angles θ1, θ2) of the proximity sensor 63 and the determination reference values D1, D2 of the pinching error determination unit 8 are also adjusted accordingly. Can be changed and set. Moreover, although the open cylinder 7 and the compressed air drive mechanism are exemplified as the high-speed auxiliary drive source, the present invention is not limited to this. For example, a device driven by a hydraulic drive mechanism or an electric actuator may be used. Various other modifications and applications of the present invention are possible.

1: Transfer device 11, 111, 112, 113: Transfer cassette 2: Transfer base 25: Finger support tube 26: Finger support member 3: Finger pair 31: Finger 4: Finger drive unit 41: Finger opening / closing rod 42: Grip lever ( (Specific drive member) 43: drive lever 5: transfer drive unit 51: sector gear 52: rack gear 53: reverse setting unit 54: connecting plate 6: finger drive detection unit 61: attack piece 62: detection plate 63: proximity sensor 7: open cylinder (High-speed auxiliary drive source)
71: Cylinder member 72: Piston member 8: Clamping error determination unit 9: Forging machine 91: Base 93: Die 96: Punch 97: Main drive source 9D: Transfer cam 9F: Open close cam

Claims (5)

A transfer base disposed in a conveying path for conveying the workpiece of a forging machine that performs forging forming by pressing the workpiece with a die and a punch;
A pair of fingers provided in the transfer base and configured to open and close to clamp and open the workpiece;
A finger drive unit for driving the opening and closing operation of the finger pair;
A transfer drive unit that drives the transfer base to move the finger pair holding the workpiece from the upstream side to the downstream side of the transport path, and returns the finger pair that opened the workpiece from the downstream side to the upstream side; A forging machine transfer device comprising:
A finger drive detection unit for detecting a drive state of some of the specific drive members constituting the finger drive unit;
A pinching error determination unit that determines a pinching error in which the finger pair failed to pinch the workpiece, based on the driving state of the specific driving member detected when the transfer base is in a specific state;
The forging machine transfer device further equipped. The transfer driving unit rotationally drives the transfer base,
The specific drive member rotates in conjunction with the transfer base,
2. The transfer device for a forging machine according to claim 1, wherein the clamping error determination unit determines the clamping error based on a driving state of the specific drive member detected when the transfer base is at a specific rotation angle.   The pinching error determination unit is at a rotation angle before the transfer base starts to rotate and when the finger pair is on the upstream side, and at a rotation angle after the transfer base starts to rotate. 3. The transfer device for a forging machine according to claim 2, wherein the clamping error is determined when the finger pair is in the middle of moving from the upstream side to the downstream side. In addition to the main drive source for driving the punch and the finger drive unit, the apparatus further comprises a high-speed auxiliary drive source for driving the finger pair to open at high speed,
The clamping error determination unit controls the high-speed auxiliary drive source to open the finger pair to forcibly drop the workpiece when the clamping error is determined. The forging machine transfer device according to item.   5. The transfer device for a forging machine according to claim 4, wherein the main drive source is a motor, and the high-speed auxiliary drive source includes any one of a compressed air drive mechanism, a hydraulic drive mechanism, and an electric actuator.

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