JP2015229180A - Multistage-type pressure molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to correctly perform positional adjustment of a movable mold of a multistage-type pressure molding machine without large-sizing and increasing of a cost of the machine.SOLUTION: A multistage-type pressure molding machine 100 is equipped with a position adjustment mechanism 10 which adjusts a position of a movable mold 6 with respect to a lamb 3. The position adjustment mechanism 10 includes: a motor 11; a drive shaft 13 which is rotationally driven by the motor 11; and plural power transmission mechanisms 20 which convert a rotation driving force of the drive shaft 13 as a common driving source into a slide force and transmit the slide force to each movable mold 6. Each power transmission mechanism 20 includes plural rotary members for transmitting rotation driving force, and a clutch 30. Resistance application means (spring 22c), which applies a rotational resistance unnecessary for power transmission, are provided on the rotary member (first gear 22) on a downstream side of the clutch 30 of the power transmission mechanism 20.

Description

  The present invention relates to a multistage forging machine.

  A multi-stage forging machine is for forging parts such as bolts by forging a wire cut to a predetermined size in multiple stages. Specifically, the multistage forging machine has a plurality of fixed molds attached to the fixed member, a movable member slidable with respect to the fixed member, and a plurality of movable molds attached to the movable member. A plurality of forging stations for performing different processes are formed by the fixed mold and the movable mold, which are opposed to each other, and parts are formed by sequentially performing a predetermined process on the material at each forging station.

  In the multistage forging apparatus as described above, it is necessary to adjust the position of each mold when replacing the molds (fixed mold and movable mold). For example, the multistage forging device shown in Patent Document 1 is provided with a vertical position adjusting means for moving each movable mold in the vertical direction with respect to the movable member, and a horizontal position adjusting means for moving in the horizontal direction. It has been. Specifically, a drive shaft (first transmission shaft 27, second transmission shaft 43) that is rotationally driven by a motor (first motor 16, second motor 18) is connected to a plurality of power transmission mechanisms (first interlocking mechanism 17, It is transmitted to each movable die (punch 6) via the second interlocking mechanism 19). Each power transmission mechanism is provided with a clutch (clutch mechanisms 36, 53). Thereby, since the power of one motor can be selectively transmitted to a plurality of movable molds, the number of motors can be reduced, and the structure of the molding machine can be simplified and the cost can be reduced.

JP-A-9-295095

  However, in reality, the position adjusting means as described above cannot accurately position the movable mold, and the cause is not clear. For this reason, the actual situation is that the operator performs the manual position adjustment using a measuring instrument or the like, and there is a problem that it takes a very long time to replace the mold.

  The inventor has verified the reason why the movable mold cannot be accurately positioned in the multistage forging machine as described above. As a result, it has become clear that even when the clutch provided in each power transmission mechanism is disengaged, the gear on the downstream side of the clutch may rotate. This is thought to be due to the following causes. That is, in the power transmission mechanism as described above, the upstream member and the downstream member of the clutch are coaxially arranged, and these members are often assembled so as to be relatively rotatable via a bearing. When the motor is driven to rotate with the clutch of such a power transmission mechanism disengaged, only the upstream member of the clutch should rotate and the downstream member of the clutch should be stationary, but the bearing The member on the downstream side may be rotated by the rotational resistance. In this case, since the rotational resistance of the bearing is very small, the rotational force of the downstream member that rotates with the rotational resistance is very small. However, the power transmission mechanism usually includes a booster mechanism such as a worm gear. Therefore, the movable mold may be slightly moved even with a small rotational force. In addition, the amount of movement of the movable type at this time is very small, but by repeatedly adjusting the position each time the movable type is replaced, the amount of movement of the movable type is accumulated and the deviation from the normal position cannot be ignored. This affects the dimensional accuracy of the product.

  For example, if each movable mold is directly connected to a motor and is individually driven to rotate, the clutch can be omitted, so that the above-described problems that occur when the clutch is disengaged can be avoided. However, providing the same number of motors as the movable type increases the size of the molding machine and increases the cost. In addition, if a position sensor that detects the position of the movable type is provided, a shift from the normal position of each movable type is detected, and the position of the movable type is adjusted based on the magnitude of this shift, so that the movable type Can be positioned accurately. However, since such a position sensor is expensive, the cost of the molding machine is increased.

  In view of the above circumstances, a technical problem to be solved by the present invention is to provide a multistage forging machine that can accurately adjust the position of a movable mold without increasing the size and cost. .

  The multistage forging machine of the present invention made to solve the above-mentioned problems is a fixed member, a plurality of fixed molds attached to the fixed member, a movable member slidable with respect to the fixed member, A multistage forging molding machine comprising a plurality of movable molds attached to a movable member and facing each fixed mold, and a position adjusting mechanism for adjusting the position of each movable mold relative to the movable member, wherein the position adjusting mechanism Comprises a motor, a drive shaft that is rotationally driven by the motor, and a plurality of power transmission mechanisms that convert the rotational drive force into a slide force and transmit it to each movable type using the drive shaft as a common drive source. Each power transmission mechanism includes a plurality of rotating members that transmit the rotational driving force and a clutch, and at least one of the plurality of power transmission mechanisms is downstream of the clutch. Providing the resistance imparting means for imparting unnecessary rotational resistance to the force transmitted to the rotary member and said.

  Thus, the multistage forging machine of the present invention is provided with resistance applying means for positively applying rotational resistance to the rotating member on the downstream side of the clutch of the power transmission mechanism. As a result, when the clutch is disengaged, the rotation of the rotating member downstream of the clutch can be restricted by the rotation resistance of the resistance applying means. Can be avoided. Thus, the movable mold can be positioned with high accuracy by the position adjustment mechanism without directly connecting each movable mold to the motor or providing a position sensor for detecting the position of the movable mold.

  In the case where the power transmission mechanism includes a speed reducing portion, if the resistance applying means is provided on the rotating member on the upstream side of the speed reducer, the rotation of the rotating member can be restricted with a relatively small resistance force.

  Various specific examples of the resistance applying means are conceivable. For example, a dummy gear can be meshed with a gear as a rotating member provided in the power transmission mechanism, and the resistance applying means can be configured by this dummy gear. However, in this case, it is necessary to secure a space for providing the dummy gear, which increases the size of the molding machine.

  Therefore, the plurality of rotating members include a first gear and a second gear that mesh with each other, and the first gear forms one gear member that forms a tooth surface on one side in the rotation direction of each gear tooth, and each gear tooth. The other gear member forming a tooth surface on the other side of the rotation direction, and the resistance applying means for applying resistance to relative rotation between the one gear member and the other gear member, the one gear member The first gear and the second gear can be engaged with each other while relatively rotating the gear member and the other gear member. Since the required space of the first gear is almost the same as that of a normal gear, an increase in the size of the molding machine can be avoided.

  For example, the resistance applying means can be constituted by a biasing member that biases the one gear member and the other gear member in the relative rotational direction. Such a gear is generally called a scissor gear, and when the first gear and the second gear are engaged with each other, it is necessary to relatively rotate the pair of gear members against the urging force of the urging member. Rotational resistance is applied to the first gear by the amount of the force against the urging force of the urging member.

  Further, the resistance applying means can be constituted by an urging member that urges the one gear member and the other gear member in a direction in which the one gear member approaches the other gear member in the axial direction. Such a gear is generally called a friction gear, and the two gear members are pressed against each other by the urging force of the urging member, whereby a frictional force is applied when the two gear members rotate relative to each other. When the first gear and the second gear are meshed with each other, it is necessary to relatively rotate the pair of gear members against the frictional force between the two gear members. A rotational resistance is applied to the gear.

  By the way, a gear (for example, scissor gear or friction gear) composed of a pair of gear members and resistance applying means as described above is in a state in which the tooth surfaces on both sides in the rotational direction of each gear tooth are pressed against the gear teeth of the other gear (that is, Since power transmission can be performed (in the state of backlash 0), it is usually provided to reduce the hitting sound between the gears caused by the backlash. When the scissors gear or the friction gear meshes with other gears, the inventors need a force to relatively rotate the pair of gear members against the biasing force of the biasing means and the frictional force of both gear members. The present invention has been conceived by paying attention to the fact that the rotational resistance is applied by the amount of the urging force and the frictional force.

  As described above, according to the multistage forging machine of the present invention, it is possible to accurately adjust the position of the punch without causing an increase in size and cost.

It is a side view of the multistage type forging molding machine which concerns on one Embodiment of this invention. It is a top view of the said multistage forging machine. It is a front view of the power transmission mechanism provided in the multistage forging machine. It is a side view of the power transmission mechanism. (A)-(c) is sectional drawing which shows the procedure which shape | molds a raw material with a fixed mold | type and a movable mold | type. (A) is the side view which looked at the 1st gear from the axial direction, (b) is XX sectional drawing of (a) figure. (A) is a side view of one gear member constituting the first gear, and (b) is a side view of the other gear member constituting the first gear. (A) And (b) is a side view which shows a mode that a 1st gear and a 2nd gear rotate, meshing | engaging. It is sectional drawing of the 1st gear periphery of the multistage type forging machine which concerns on other embodiment.

  As shown in FIG. 1, a multistage forging machine 100 according to an embodiment of the present invention is based on a base 1, a die block 2 as a fixing member fixed to the base 1, and a die block 2. A ram 3 as a movable member provided so as to be slidable, and a drive unit 4 for driving the ram 3 are provided. As shown in FIG. 2, a plurality (six in the illustrated example) of fixed dies 5 are attached to the die block 2, and the same number of movable dies 6 as the fixed dies 5 are attached to the ram 3. Each fixed mold 5 and each movable mold 6 are opposed to each other in the sliding direction of the ram 3 and constitute forging stations S1 to S6 that perform different processes. In this embodiment, a horizontal multistage forging machine 100 in which the ram 3 slides in the horizontal direction is shown. In the following description, the sliding direction of the ram 3 (the left-right direction in FIGS. 1 and 2) is referred to as the front-rear direction, and the horizontal direction orthogonal to the front-rear direction (the direction perpendicular to the plane of FIG. 1, the up-down direction in FIG. 2). This is called the width direction. The side where the ram 3 approaches the die block 2 is referred to as the front, and the side where the ram 3 is separated from the die block 2 is referred to as the rear.

  The drive unit 4 includes a main motor 4a, a flywheel shaft 4b, a main crankshaft 4c, and a main connecting rod 4d. The rear end portion of the main connecting rod 4d is attached to the crank pin of the main crankshaft 4c, and the front end portion of the main connecting rod 4d is attached to the ram 3. By driving the main motor 4a to rotate, the flywheel shaft 4b and the main crankshaft 4c rotate, whereby the ram 3 slides in the front-rear direction via the main connecting rod 4d.

  The multistage forging machine 100 is provided with an extrusion mechanism 7 for extruding a molded product from the fixed mold 5. The push-out mechanism 7 includes a kicker shaft 7a that can project into a cavity in the fixed mold 5, a kicker link 7b, a kicker connecting rod 7c, a kicker crankshaft 7d, and a gear 7e provided on the kicker crankshaft 7d. The The gear 7e meshes with a gear 4e provided on the main crankshaft 4c. When the ram 3 is moved backward to open the mold, the rotational driving force of the main crankshaft 4c of the drive unit 4 is transmitted to the kicker shaft 7a via the gear 7e, the kicker crankshaft 7d, the kicker connecting rod 7c, and the kicker link 7b. Thus, the tip of the kicker shaft 7 a protrudes into the cavity in the fixed mold 5, and the molded product is pushed out from the fixed mold 5.

  The multistage forging machine 100 is provided with a punch shaft 8 that can project into the movable die 6 and a punch drive mechanism 9 that drives the punch shaft 8. The punch shaft 8 functions to extrude a molded product when it is held on the movable die 6 or when the punch 6b is provided inside the movable die 6 (see FIG. 3), the punch 6b is extruded to mold the material. Fulfills the function of

  The punch drive mechanism 9 has one end pivotally attached to the main connecting rod 4d, the other end fixed to the cam 9a, a cam follower 9c attached to one end, and the other end abutting against the punch shaft 8 from the rear. It is comprised with the 2nd punch link 9d distribute | arranged to the position which can contact | connect. The rotating shaft 9a1 of the cam 9a and the rotating shaft 9d1 of the second punch link 9d are attached to the ram 3. When the main motor 4a is rotated, the main crankshaft 4c is rotated, and the cam 9a is rotated in the direction of the arrow in FIG. 1 through the first punch link 9b. Thereby, the cam follower 9c is pushed down in the figure, the second punch link rotates in the direction of the arrow in FIG. 1, and the punch shaft 8 is pushed forward at the other end of the second punch link. At this time, the timing of pushing the punch shaft 8 forward can be adjusted by adjusting the shape of the cam surface (contact surface with the cam follower 9c) of the cam 9a, the bending angle of the second punch link 9d, and the like.

  Molding by the multistage forging machine 100 is performed in the following procedure. First, the wire supplied from the coil is cut into a predetermined length by a cutting device (not shown), and the cut material is supplied to the first forging station S1 by a transfer means (not shown). In this state, the drive unit 4 is driven to advance the ram 3, and the movable mold 6 and the fixed mold 5 are clamped to perform predetermined processing on the material. Thereafter, the drive unit 4 is driven to move the ram 3 backward, and the material molded at each forging station is pushed out from the fixed mold 5 by the extruding mechanism 7 and conveyed to the second forging station S2 by the conveying means. Is carried into the first forging station S1. By repeating the above, the material is sequentially conveyed to each forging station S1 to S6, and forging is performed on the material in multiple stages.

  The multistage forging machine 100 is provided with a position adjusting mechanism for adjusting the position of each movable mold 6 relative to the ram 3. In the present embodiment, a position adjustment mechanism 10 that adjusts the position of each movable mold 6 in the front-rear direction is provided. Specifically, as shown in FIG. 2, the position adjusting mechanism 10 includes a motor 11, a first drive shaft 12 and a second drive shaft 13 that are rotationally driven by the motor 11, and a rotational drive of the second drive shaft 13. And a plurality of power transmission mechanisms 20 that convert the force into a sliding force and transmit it to each movable mold 6.

  One end of the first drive shaft 12 is directly connected to the motor 11, and the other end is rotatably supported by a bearing 14. In the present embodiment, a detection unit 15 that detects the rotation angle of the first drive shaft 12 is provided at the other end of the first drive shaft 12. Based on the rotation angle of the first drive shaft 12 detected by the detection unit 15, the position in the front-rear direction of the movable mold 6 described later can be indirectly detected. The motor 11, the bearing 14, and the detection unit 15 are attached to the base 1, and the first drive shaft 12 rotates at a fixed position on the base 1.

  The second drive shaft 13 is orthogonal to the first drive shaft 12 and is provided on the upper surface of the ram 3. The first drive shaft 12 and the second drive shaft 13 are connected via a first bevel gear 16 and a second bevel gear 17 so that power can be transmitted. The first bevel gear 16 is attached to the first drive shaft 12 so as to be able to transmit torque and slide in the axial direction (front-rear direction). Thereby, even when the second drive shaft 13 moves in the front-rear direction along with the longitudinal movement of the ram 3, the drive force of the first drive shaft 12 can be transmitted to the second drive shaft 13.

  The power transmission mechanism 20 is provided for each of the plurality of movable dies 6, and uses the second drive shaft 13 as a common drive source to exchange the rotational driving force with a sliding force and transmit it to each movable die 6. Hereinafter, the configuration of the power transmission mechanism 20 will be described in detail.

  The power transmission mechanism 20 includes a plurality of rotating members that transmit a rotational driving force, and a clutch 30 that can transmit and disconnect the rotational driving force. In the present embodiment, as a plurality of rotating members, as shown in FIGS. 3 and 4, a first gear 22 provided on the outer periphery of the second drive shaft 13, a second gear 23 meshing with the first gear 22, A worm shaft 24 that rotates integrally with the second gear 23, a worm wheel 25 that meshes with the worm shaft 24, and a screw member 26 that rotates integrally with the worm wheel 25 are provided.

  The first gear 22 is composed of, for example, a spur gear, and is attached to the outer periphery of the second drive shaft 13 via a bearing 21 (ball bearing in the illustrated example). As a result, the first gear 22 is rotatable relative to the second drive shaft 13.

  The second gear 23 is constituted by a spur gear, for example, and is fixed to one end of the worm shaft 24. The second gear 23 has a rotating shaft parallel to the first gear 22 and meshes with the first gear 22. In the illustrated example, the first gear 22 and the second gear 23 have the same diameter. The worm 24 a of the worm shaft 24 meshes with the worm wheel 25, and the worm 24 a and the worm wheel 25 constitute a first speed reduction unit that decelerates the rotation of the worm shaft 24.

  A cylindrical screw member 26 having a thread groove formed on the inner periphery is fixed to the worm wheel 25. A slide member 27 having a screw groove formed on the outer periphery is inserted into the inner periphery of the screw member 26. The screw groove of the screw member 26 and the screw groove of the slide member 27 are screwed together, and rotating the screw member 26 causes the slide member 27 to slide in the left-right direction in FIG. Thus, the screw groove of the screw member 26 and the screw groove of the slide member 27 convert the rotation of the screw member 26 into the second reduction part that decelerates the rotation of the screw member 26 and the slide of the slide member 27 into a linear slide. A first conversion unit is configured.

  A cam 28 is fixed to the tip of the slide member 27. The cam 28 is provided with an inclined surface 28a on the front surface (the lower surface in FIG. 4). A cam follower 29 is provided in front of the cam 28. The cam follower 29 is guided so as to be slidable with respect to the ram 3 in the front-rear direction (vertical direction in the figure). An inclined surface 29 a parallel to the inclined surface 28 a of the cam 28 is provided on the rear surface of the cam follower 29. An inclined surface 28a provided on the front surface of the cam 28 and an inclined surface 29a provided on the rear surface of the cam follower 29 are slidably in contact with each other. The cam follower 29 is urged rearward by urging means (not shown). By moving the cam 28 in the horizontal direction in the figure, the cam follower 29 moves in the front-rear direction (vertical direction in the figure). Thus, the inclined surface 28 a of the cam 28 and the inclined surface 29 a of the cam follower 29 constitute a second conversion unit that converts the slide in the width direction of the cam 28 into a slide in the front-rear direction of the cam follower 29.

  The movable mold 6 is attached to the cam follower 29. As a result, the cam follower 29 and the movable die 6 are slid in the front-rear direction integrally with the ram 3 by sliding the cam 28 in the width direction. In the illustrated example, the movable die 6 includes a movable die 6a fixed to the cam follower 29, and a punch 6b provided on the inner periphery thereof and capable of moving back and forth with respect to the movable die 6a. The punch 6b is driven forward by the punch shaft 8, and is urged rearward (upward in FIG. 4) by urging means (not shown). The position of the punch 6b in the front-rear direction relative to the ram 3 at the completion of molding is determined by the stroke of the ram 3, the stroke of the punch shaft 8 by the punch drive mechanism 9, and the like. On the other hand, the position of the movable die 6a in the front-rear direction relative to the ram 3 at the completion of molding can be adjusted by the position adjusting mechanism 10. In the present embodiment, after setting the material W on the fixed mold 5 as shown in FIG. 5A, the ram 3 is advanced and fixed to the movable die 6a of the movable mold 6 as shown in FIG. 5B. The mold 5 is brought into contact, and then the punch 6b is pushed forward by the punch shaft 8 to form the material W by forging. In this case, the position of the movable die 6a is adjusted in advance by the position adjustment mechanism 10 and the relative position between the movable die 6a and the punch 6b at the time of completion of the press {state in FIG. 5C} is adjusted. The axial direction dimension of the flange part W1 shape | molded by W can be adjusted.

  The clutch 30 is provided between members arranged coaxially so as to be relatively rotatable via a bearing. In the present embodiment, the clutch 30 is provided between the second drive shaft 13 and the first gear 22 fixed to the inner ring and the outer ring of the bearing 21 (see FIG. 3). By appropriately connecting or disconnecting the clutch 30 of each power transmission mechanism 20, the rotational driving force of the second drive shaft 13 can be selectively transmitted to the plurality of movable dies 6. By connecting the clutch 30, the rotation of the second drive shaft 13 is transmitted to the first gear 22, and these rotate integrally. By disconnecting the clutch 30, even when the second drive shaft 13 rotates, the first gear 22 is maintained in a stationary state without rotating. The place where the clutch is provided is not limited to the above, and may be provided between a plurality of rotating members. For example, although not shown in the figure, the second gear 23 and the worm shaft 24 are coaxially arranged so as to be relatively rotatable via bearings, and a clutch is provided between the second gear 23 and the worm shaft 24, The rotational driving force may be transmitted and disconnected.

  The position adjustment in the front-rear direction with respect to the ram 3 of the movable mold 6 by the position adjustment mechanism 10 is performed as follows. First, when adjusting the position of the movable mold 6 of the first forging station S1, the clutch 30 of the power transmission mechanism 20 of the first forging station S1 is connected and the power transmission mechanisms 20 of the other forging stations S2 to S6 are connected. The clutch 30 is disconnected. By rotating the motor 11 in this state, only the movable mold 6 of the first forging station S1 is moved in the front-rear direction via the power transmission mechanism 20. Then, by rotating the motor 11 by a predetermined rotation angle, the movable die 6 moves forward or backward by a predetermined dimension, and is disposed at a desired front-rear direction position with respect to the ram 3. Thereafter, similarly, the position adjustment of the movable mold 6 of the second to sixth forging stations S1 is performed.

  When the position of the movable mold 6 is adjusted as described above, in the power transmission mechanism 20 with the clutch 30 disconnected, the first gear 22 should be stationary even when the second drive shaft 13 is rotated. However, even in this case, the first gear 22 tends to rotate with the rotation of the second drive shaft 13 due to the rotational resistance of the bearing 21. If the first gear 22 rotates along with the rotation of the second gear 23 and the worm shaft 24, the worm 24a comes into contact with the worm wheel 25 and the worm wheel 25 rotates slightly, so that the screw member 26, The movable die 6 may slightly move back and forth through the slide member 27, the cam 28, and the cam follower 29. Therefore, the multistage forging machine 100 described above is provided with resistance applying means that positively applies rotational resistance to each power transmission mechanism 20. The rotational resistance imparted by the resistance imparting means is not a rotational resistance inevitably generated when power is transmitted through the rotating member, but is a rotational resistance unnecessary for power transmission.

  In the present embodiment, resistance imparting means is provided on the gear on the upstream side of the first reduction gear (the meshing portion between the worm 24a and the worm wheel 25). In the illustrated example, the first gear 22 is provided with resistance applying means. Specifically, as shown in FIG. 6, the first gear 22 applies resistance to a pair of gear members 22a and 22b arranged on the same axis and a relative rotation of the pair of gear members 22a and 22b. Means. The first gear in the illustrated example is a so-called scissor gear, and is provided with a biasing member (for example, a spring 22c) that biases the pair of gear members in a direction in which the pair of gear members are relatively rotated. The biasing member is not limited to a spring, and may be, for example, rubber or an air cylinder. The pair of gear members 22a and 22b have gear teeth 22a1 and 22b1 having the same pitch. In the present embodiment, one of the pair of gear members 22a and 22b is made of metal, and the other is made of resin. One gear member 22a is provided with a plurality of holes 22a2 at equal intervals in the circumferential direction {see FIG. 7 (a)}. The other gear member 22b is provided with a plurality of convex portions 22b2 at equal intervals in the circumferential direction {see FIG. 7 (b)}. In the illustrated example, the convex portion 22b2 has a cylindrical shape. The convex portion 22b2 of the other gear member 22b is inserted into the hole 22a2 of the one gear member 22a, and the springs 22c are arranged in a compressed state between the inner wall of the hole 22a2 and the protrusion 22b2. Due to the elastic force of the spring 22c, the pair of gear members 22a, 22b are in the relative rotation direction (specifically, the direction in which the tooth surfaces on both sides of each gear tooth are separated, that is, the direction in which the circumferential gap between the gear teeth is narrowed). The relative rotation is restricted in a state where the inner wall of the hole 22a2 and the convex portion 22b1 are engaged. At this time, as shown in FIG. 6A, the phases of the gear teeth 22a1 and 22b1 of the pair of gear members 22a and 22b are shifted.

  The first gear 22 is engaged with the second gear 23 in a state in which the pair of gear members 22a and 22b of the first gear 22 are relatively rotated by an external force and the phases of the gear teeth 22a1 and 22b1 are substantially matched. And the second gear 23 are assembled. In this state, both gear members 22a and 22b are integrated by inserting a bolt (see the chain line) into the convex portion 22b2 and attaching a nut or the like (not shown) to the tip. At this time, the tightening force of the bolt is adjusted so that the two gear members 22a and 22b can be relatively rotated. In a state where the first gear 22 and the second gear are engaged with each other, as shown in FIG. 8 (a), the tooth surface on the rotation direction leading side of each gear tooth of the first gear 22 is the gear of one gear member 22a. The tooth surface formed by the teeth 22a1 and the tooth surface on the rear side in the rotation direction of each gear tooth of the first gear is formed by the gear teeth 22b1 of the other gear member 22b. The gear teeth 22a1 and 22a1 of the pair of gear members 22a and 22b of the first gear 22 are pressed against the tooth surface 23a facing the circumferential direction of the second gear 23 by the urging force of the spring 22c.

  When the first gear 22 is rotated in this state, as shown in FIG. 8B, the gear teeth 22a1 and 22b1 of the pair of gear members 22a and 22b are located between the tooth surfaces of the second gear 23 while compressing the spring 22c. {In FIG. 8 (b), the phases of both gear teeth 22a1, 22b1 are substantially matched}. Power is transmitted while repeating the above. That is, when power is transmitted between the first gear 22 and the second gear 23, an extra force for compressing the spring 22c is required, and the first gear 22 has a rotational resistance corresponding to this force. Is granted.

  Thus, by using the first gear 22 as a scissor gear, even when the first gear 22 is about to be rotated by the rotation resistance of the bearing 21, the rotation is restricted by the rotation resistance due to the elastic force of the spring 22c. Can do. Thereby, rotation of the rotation member which comprises the power transmission mechanism 20 can be controlled reliably, and the minute position shift of the movable mold | type 6 can be prevented. At this time, if the elastic force of the spring 22c is too large, the rotational resistance of the first gear 22 becomes too large, and the first gear 22 rotates when the position of the movable mold 6 is adjusted (that is, when the clutch 30 is connected). There is a risk that it will not be possible. On the other hand, if the elastic force of the spring 22c is too small, the rotation resistance of the first gear 22 is insufficient, and the rotation of the first gear 22 due to the rotation resistance of the bearing 21 cannot be reliably prevented when the clutch 30 is disconnected. There is a fear. From the above, the elastic coefficient of the spring 22c is set so that the first gear 22 can be rotated when the clutch 30 is connected and the rotation of the first gear 22 can be restricted when the clutch 30 is disconnected. The

  Moreover, in this embodiment, since the resistance provision means is provided in the 1st gear 22 provided in the upstream of the deceleration part, rotation of the 1st gear 22 grade | etc., Can be controlled with comparatively small force.

  In the present embodiment, the gear teeth 22a1 and 22b1 of the pair of gear members 22a and 22b constituting the first gear 22 always slide with the tooth surface 23a of the second gear 23. The surface is easily worn. Thus, as described above, one of the pair of gear members 22a and 22b of the first gear 22 is made of resin, so that the resin gear member is actively worn, and the other gear member or the second gear is worn. 23 wear can be suppressed. Further, by actively abrading the resin gear member, it is only necessary to replace the resin gear member during maintenance, thereby facilitating maintenance.

  The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the case where the first gear 22 is provided with the resistance applying means has been described. However, the present invention is not limited to this, and the other rotating member (for example, the second gear 23) may be provided with the resistance applying means. .

  Further, the resistance applying means is not limited to the above. For example, in the embodiment shown in FIG. 9, the first gear 22 is a so-called friction gear. Specifically, the first gear 22 of the present embodiment includes a pair of gear members 22c, 22d arranged coaxially, a spacer 22e arranged between the axial directions of the two gear members 22c, 22d, and one gear. A spring (for example, a disc spring 22f) is provided as a biasing unit that biases the member 22c and the other gear member 22d in a direction approaching in the axial direction. In the illustrated example, a disc spring 22f is disposed between the other gear member 22e and the bracket 22g in the axial direction, and the other gear member 22e is biased toward the one gear member 22d by the biasing force of the disc spring 22f. To be pressed against the spacer 22e. One gear member 22d and the other gear member 22e have different numbers of teeth. For example, the number of teeth of one gear member 22d is designed to be one more or less than the number of teeth of the other gear member 22e. When the first gear 22 is rotated, the first gear 22 and the second gear 23 are engaged with each other while the gear members 22c and 22d are relatively rotated, as in the above-described embodiment shown in FIG. At this time, both the gear members 22c and 22d are pressed against each other via the spacer 22e by the disc spring 22f, so that the frictional force at the time of relative rotation of the both gear members 22c and 22d increases. While the first gear 22 rotates while rotating both the gear members 22c and 22d against this frictional force, a rotational resistance is applied to the first gear 22. That is, the disc spring 22f constitutes a resistance applying unit that applies rotational resistance to the first gear 22.

  Further, the resistance applying means is not limited to the above as long as it actively applies a rotational resistance unnecessary for power transmission to the first gear 22. For example, the resistance applying unit may be configured by the first gear 22, the second gear 23, or a dummy gear (not shown) that meshes with both. However, in this case, since a space for providing the dummy gear is required, from the viewpoint of space saving, it is preferable to configure the resistance applying means by the urging means incorporated in the gear as in the above embodiment.

  Further, the resistance applying means is not necessarily provided in all the power transmission mechanisms 20, but only at least one of the plurality of power transmission mechanisms 20, for example, the power transmission mechanism 20 in which the displacement of the movable mold 6 is a concern. May be provided.

  Further, in the above embodiment, the case where the movable die 6 is constituted by the movable die 6 a and the punch 6 b is shown, but the present invention is not limited to this, and the movable die 6 is constituted only by the punch, and this punch is interposed via the cam follower 29. It is good also as a structure fixed to the ram 3.

1 base 2 die block (fixing member)
3 Ram (movable member)
4 Drive unit 5 Fixed die 6 Movable die 7 Extrusion mechanism 8 Punch shaft 9 Punch drive mechanism 10 Position adjustment mechanism 11 Motor 12 First drive shaft 13 Second drive shaft 20 Power transmission mechanism 21 Bearing 22 First gear 22a, 22b gear member 22c Spring (biasing member, resistance applying means)
23 Second gear 24 Worm shaft 25 Worm wheel 26 Screw member 27 Slide member 28 Cam 29 Cam follower 30 Clutch 100 Multistage forging machine

Claims (5)

A fixed member, a plurality of fixed molds attached to the fixed member, a movable member slidable with respect to the fixed member, a plurality of movable molds attached to the movable member and opposed to the fixed molds, A multistage forging molding machine provided with a position adjustment mechanism for adjusting the position of each movable mold with respect to the movable member,
The position adjusting mechanism includes a motor, a drive shaft that is rotationally driven by the motor, and a plurality of power transmissions that convert the rotational driving force into a sliding force and transmit it to each movable type using the driving shaft as a common drive source. With a mechanism,
Each power transmission mechanism includes a plurality of rotating members that transmit the rotational driving force, and a clutch.
In at least one of the plurality of power transmission mechanisms, a multistage forging molding machine is provided, wherein resistance imparting means for imparting unnecessary rotational resistance to power transmission is provided to a rotary member downstream of the clutch. .   The multistage forging machine according to claim 1, wherein the power transmission mechanism includes a speed reducing portion, and the resistance applying means is provided on a rotating member upstream of the speed reducing portion.   The plurality of rotating members include a first gear and a second gear that mesh with each other, the first gear forming one gear member that forms a tooth surface on one side in the rotation direction of each gear tooth, and the rotation of each gear tooth. The other gear member forming a tooth surface on the other side of the direction, and the resistance applying means for applying resistance to relative rotation between the one gear member and the other gear member, the one gear member and the The multistage forging machine according to claim 1 or 2, wherein the first gear and the second gear are engaged with each other while relatively rotating the other gear member.   The multistage forging machine according to claim 3, wherein the resistance applying means is a biasing member that biases the one gear member and the other gear member in a relative rotational direction.   4. The multistage forging machine according to claim 3, wherein the resistance applying means is an urging member that urges the one gear member and the other gear member in an axial direction.

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