JP2013107112A - Device for releasing stick of pressing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for releasing stick of a pressing machine that is free from a risk of oil leakage, can release stick with a minor force, has a compact configuration and is excellent in cost performance.SOLUTION: The device 20 for releasing stick of a pressing machine includes: a male spherical surface 16 provided at a lower end of a connecting rod 14 and having a first curvature radius r1; a female cylindrical surface 24 provided in a slide 11, having a second curvature radius r2 larger than the first curvature radius and decentered from the male spherical surface 16 by a predetermined offset amount e; a wedge 22 including a female spherical surface slidably coming into contact with the male spherical surface 16 and a male cylindrical surface slidably coming into contact with the female cylindrical surface 24 about a shaft center; and an operating mechanism 23 for moving the wedge 22 to a thicker side from a thinner side.

Description

  The present invention relates to a stick releasing device for a press machine.

  In press machines, when the upper and lower molds of the mold are closed near the bottom dead center or when the workpiece is stopped between the upper and lower molds, the press machine body frame is added. There is a phenomenon called a stick that is extended by pressure load and stops when the slide drive mechanism such as a connecting rod or plunger is stretched by elastic deformation of the main body frame, and the drive motor becomes incapable of both forward and reverse rotation. May occur. As a stick release device for eliminating such a stick state, a device using hydraulic pressure as in Patent Document 1 and a device using a wedge as in Patent Document 2 are known.

Japanese Patent Laid-Open No. 4-112000 JP 54-57450 A

  In the case of a hydraulic stick release device such as that disclosed in Patent Document 1, an oil pressure generation source, an actuator provided at a connecting portion between a connecting member and a slide, and a circuit for controlling the actuator are required. Cost is high. In addition, there is a risk of oil leakage due to aging of the packing and loose piping. In particular, in the case of a press machine using a servo motor, a hydraulic overload prevention device may not be used because overload is prevented by controlling torque with the servo motor. Therefore, a mechanical stick release device is desired.

  Further, in a press machine using a wedge as in Patent Document 2, when a stick is made, a force equal to or greater than the press molding load remains applied to the wedge in the press load direction. In order to cancel this stick state, it is necessary to move the wedge in a direction perpendicular to the press load direction (lateral direction). In order to move the wedge, the wedge is pulled out with a force that exceeds the friction force generated in the direction perpendicular to the press load direction (lateral direction) due to the force acting on the wedge in the press load direction. There is a need. The force required to move the wedge is large. If you try to move the wedge by manually rotating the screw, if you reduce the screw lead, it takes time to rotate the screw. Conversely, if you increase the screw lead. The torque required for the rotation of the screw increases, making manual operation difficult. Therefore, it is necessary to use an actuator such as a motor or a hydraulic cylinder as a power source for moving the wedge. Therefore, a large space as a whole and a control circuit for controlling them are required, and the cost is increased.

  An object of the present invention is to provide a compact stick release device that is free from the risk of oil leakage, can release a stick with a relatively light force, and is compact and excellent in cost performance. It is an issue.

A stick release device for a press machine of the present invention is a stick release device provided at a connecting portion between a connecting member and a slide, and is provided at a lower end of the connecting member and has a male curved surface having a first radius of curvature, A female curved surface provided on the slide, having a second radius of curvature larger than the first radius of curvature, decentered from the male curved surface, a concave surface slidably contacting the male curved surface, and the female curved surface And a wedge having a convex surface that slidably abuts, and a moving means for moving the wedge from a state in which the thick portion is interposed between the male curved surface and the female curved surface to a state in which the thin portion is interposed. (Claim 1).

  In such a stick releasing device, it is preferable that the male curved surface of the connecting member and the concave surface of the wedge contacting the same are spherical surfaces. Further, it is preferable that the female curved surface of the slide and the convex surface of the wedge contacting the female curved surface are cylindrical surfaces. Further, it is more preferable that the moving means includes a screw mechanism that converts a rotation operation into an operation of moving a wedge (claim 4).

  The stick release device (Claim 1) of the press machine according to the present invention can be pulled out by sliding with a rotational movement of the wedge by using a curved wedge. According to this, it is possible to provide a force point for rotating the wedge at a position away from the sliding surface with the rotation center as a reference. Therefore, the stick can be released with a smaller force than in the conventional device in which a force point exists between the two surfaces of the wedge.

  When the male curved surface of the connecting member and the concave surface of the wedge that abuts on the spherical surface are spherical surfaces (claim 2), a ball-type connecting point that has been widely used in the past can be employed. In addition, the reaction force of pressurization in various directions can be stably received.

  When the female curved surface of the slide and the convex surface of the wedge abutting on it are cylindrical surfaces (claim 3), the manufacturing and processing are easy, and the movement of the wedge is stable.

  When the moving means is provided with a screw mechanism that converts a rotation operation into an operation of moving the wedge (Claim 4), the stick can be released by a lighter operation, and the wedge is locked by the screw locking function. Can be fixed so as not to move.

It is principal part side surface sectional drawing which shows one Embodiment of the press machine provided with the stick release apparatus of this invention. It is a partial cross section principal part front view of the press machine of FIG. It is sectional drawing which shows one Embodiment of the stick release apparatus of this invention. It is a principal part enlarged view of FIG. It is a principal part enlarged view of FIG. It is a top view which shows one Embodiment of the wedge in connection with this invention. It is a front view of the wedge of FIG. It is a perspective view of the wedge of FIG.

  1 and 2 show the vicinity of a slide 11 of a so-called C frame type press machine 10. The press machine 10 includes a frame 12, a crankshaft 13 rotatably supported by the frame, a connecting rod 14 having a large end connected to an eccentric portion of the crankshaft, and a small end of the connecting rod. And a slide 11 guided up and down by a frame 12. The crankshaft 13 extends in the front-rear direction of the press machine 10, and a main gear 15 is fixed to the rear end. For example, a pinion driven by a servo motor (not shown) meshes with the main gear 15.

A male spherical surface 16 is provided at the lower end of the connecting rod 14. The connecting rod 14 includes a main body 14a and a ball member 14b coupled to the main body by a screw so that the length thereof can be adjusted. The male spherical surface 16 is formed by a lower half surface of the ball portion of the ball member 14b. ing. The radius of curvature r1 of the male spherical surface 16 is the same as the radius of the ball portion of the ball member 14b. On the upper surface side of the ball portion, a worm wheel 17 is covered so as to be able to transmit torque around the axis of the ball member 14b and swing freely. As shown in FIG. 3, for example, as shown in FIG. 3, the inner surface of the worm wheel 17 is formed on a female spherical surface 17a that slidably contacts the male spherical surface 16 and is vertically connected to the inner surface. A groove 17b may be formed, and a pin 16a movable along the vertical groove may be provided on the ball member 14b.

  As shown in FIG. 3, the worm wheel 17 is rotatably held with respect to the slide 11 by a retainer 18, and teeth 17c meshing with the worm are formed on the outer periphery. The connecting rod main body 14a, the ball member 14b screwed with the main body 14a, the worm wheel 17 and the worm constitute a conventionally known die height adjusting device. When the worm is rotated, the ball member 14b is screwed up and down with respect to the main body 14a, and the height at the bottom dead center of the slide 11, that is, the die height can be adjusted.

  As shown in FIG. 4, a stick release device 20 is interposed between the connecting rod 14 and the slide 11. The stick release device 20 includes a male spherical surface 16 on the lower surface of the ball member 14b, a receiving seat 21 fixed to the inner bottom of the slide 11, a wedge 22 interposed between the male spherical surface 16 and the receiving seat 21, An operating mechanism 23 for operating the wedge 22 back and forth (left and right in FIG. 4) is provided.

The receiving seat 21 is a columnar member, and the upper surface thereof is a female cylindrical surface 24 whose axial center extends in the left-right direction of the press machine. The wedge 22 is also a cylindrical member (see FIGS. 6 to 8), and its upper surface is a female spherical surface 25 that slides with the male spherical surface 16. On the other hand, the lower surface is a male cylindrical surface 26 that slides with the female cylindrical surface 24 of the receiving seat 21. That is, the center P1 of the male spherical surface 16 shown in FIG. 3 and the center of the female spherical surface portion 25 of the wedge 22 coincide with each other, and the axis P2 of the female cylindrical surface 24 and the axis of the male cylindrical surface 26 also coincide. The curvature radius r 2 of the lower male cylindrical surface 26 of the wedge 22 is larger than the curvature radius r 1 of the upper female spherical surface 25. Further, a vertical line passing through the center P1 of the spherical surfaces 16 and 25 (ball member 14
(center line b) C1 and the vertical plane C2 passing through the axial center P2 of the cylindrical surfaces 24 and 26 are eccentric by a predetermined offset amount e in the front-rear direction of the press machine (left-right direction in FIG. 3) (see FIG. 6). ).

  As a result, as shown in FIG. 4, the wall thickness T of the wedge 22 is thin on the front side (left side of FIG. 4) and thick on the rear side (right side of FIG. 4). Presents a wedge shape. That is, if the cylindrical surfaces 24 and 26 and the spherical surfaces 16 and 25 are concentric, the thickness T of the wedge 22 is constant, but by making it eccentric as described above, the thickness T gradually increases toward the rear side. It has become. Therefore, when the wedge 22 is displaced rearward (right in FIG. 4), a thin portion is interposed between the receiving seat 21 and the male spherical surface 16 (see an imaginary line J in FIG. 4). Thereby, when a stick arises in a press machine, a stick can be canceled by shifting wedge 22 back.

  Next, the operation mechanism 23 will be described with reference to FIGS. A guide groove 21a extending in the front-rear direction of the press machine is formed on the lower surface side of the receiving seat 21, and a slide member 28 is slidably accommodated in the guide groove. A pin 29 is fixed to the approximate center (see FIG. 6) of the wedge 22 and protrudes downward. The lower end of the pin 29 and the tip of the slide member 28 (right side in FIG. 4) are connected to each other by a ball socket joint (spherical joint) 30 so as to be swingable. In this embodiment, a ball 31 is attached to the pin 29 and a socket 32 is provided on the slide member 28.

  The pin 29 is fitted to the ball 31 so as to be movable in the axial direction, so that a deviation between the arc-shaped motion of the tip of the pin 29 and the linear motion of the slide member 28 is allowed. The pin 29 may be fitted to the wedge 22 so as to be movable in the axial direction. As shown in FIG. 4, a large-diameter portion 29a is provided at the center in the length direction of the pin 29, and the large-diameter portion 29a is loosely fitted to the receiving seat 21 to swing the pin 29. A forbidden space 21b is formed.

  A female screw 33 is formed at the base end (left side in FIG. 4) of the slide member 28, and a cap screw (hexagon socket head bolt) 34 is screwed to the female screw 33. Further, as shown in FIG. 5, the shaft portion 34 a of the cap screw 34 is rotatably supported by a cylindrical collar 35 fixed to the slide 11. The collar 35 is slidably engaged with the lower jaw surface 36a of the head 36 of the cap screw 34, thereby allowing the cap screw 34 to move in the distal direction (right side in FIG. 5) while allowing the cap screw 34 to rotate about its own axis. To prevent.

  As shown in FIG. 5, a cup-shaped stopper 37 surrounding the head 36 of the cap screw 34 is attached to the collar 35. Both are fixed to the slide 11 together with bolts or the like. This stopper 37 is slidably engaged with the top surface of the head 36 (left side in FIG. 5), and prevents the cap screw 34 from rotating in the top surface direction (left side in FIG. 5). A through-hole 38 is formed in the center of the stopper 37 for passing a hexagon wrench that turns the cap screw.

  The stick releasing device 20 configured as described above can release the stick as follows when the stick is generated in the press machine. First, a hexagon wrench is passed through the stopper hole 38 and the cap screw 34 is rotated counterclockwise (counterclockwise). As a result, the cap screw 34 tends to come out of the slide member 28. It is assumed that the cap screw 34 is a right-hand screw. For left-handed screws, rotate clockwise (clockwise). Even if the cap screw 34 is about to come out of the slide member 28, the slide member 28 is pushed to the tip side by a reaction force because the stopper 37 prevents the backward movement.

  As a result, the slide member 38 pushes the tip end portion of the pin 29 to the right, so that the pin 29 rotates around the axis P2 of the cylindrical surfaces 24 and 26, and the wedge 22 is displaced rearward. Thus, as described above, the thin portion of the wedge 22 enters between the receiving seat 21 and the male spherical surface 16, and the stick is released. Since the axis P2 of the cylindrical surfaces 24 and 26 and the center P1 of the female spherical surface 25 are decentered, strictly speaking, when the wedge 22 rotates about the axis P2, the center P1 of the female spherical surface 25 is Move some. However, since the eccentricity e is small, there is almost no influence. Further, if the heights of the center P1 of the spherical surfaces 16 and 25 and the axis P2 of the cylindrical surfaces 24 and 26 are made substantially the same, even if the wedge 22 rotates around P2, the center P1 only moves slightly downward. It is. Therefore, the influence is even smaller.

  When the stick is generated, the frame of the press machine is elastically deformed and stretched, and the force to return at that time presses the wedge 22 up and down. Therefore, the frictional resistance increases. However, the force is increased by the action of the wheel shaft when the hexagon wrench is rotated, and the force is also increased when the cap screw is rotated. When the lower end (power point) of the pin 29 is pushed to change the angle of the upper part (action point), the force is increased by the lever action. Therefore, the stick can be released with a relatively small operating force. Since the slide member 28 is locked by the action of a screw or the like, the wedge 22 does not move during normal press work.

After releasing the stick, for example, the workpiece is removed to cancel the overload state. Next, using a hexagon wrench or the like, the cap screw is rotated clockwise to retract the slide member 28. As a result, the wedge 22 returns to the home position indicated by the solid line in FIG. 4 and preparation for the next press work can be performed. When the stick state is eliminated, the slide can be moved up and down using a normal motor for adjusting the die height. After that, the slide is lifted by the motor, and the wedge 22 is unloaded. Return.

  In the above embodiment, the stick release device is applied to a C frame type press machine, but it can also be applied to a straight side type press machine. In addition to a press machine having one connecting point, the present invention can be applied to a press machine having two or more points. Moreover, although applied to the connecting part of a connecting rod and a slide in the said embodiment, it is applicable also to other connecting members, such as a plunger, and a connecting part of a slide.

  In the above embodiment, the female spherical surface is provided on the upper surface of the wedge and the male cylindrical surface is provided on the lower surface, but the spherical surface may be provided on both. Further, depending on the connecting form of the connecting rod (or plunger) and the slide, both can be provided with a cylindrical surface. The direction of the cylindrical surface is matched to the direction of bending of the connecting rod. When both are provided with a spherical surface, a female spherical surface is provided on the upper surface and a male spherical surface is provided on the lower surface. When both are provided with a cylindrical surface, a female cylindrical surface is provided on the upper surface and a male cylindrical surface is provided on the lower surface. Contrary to the embodiment of the cylindrical surface, a female cylindrical portion can be provided on the upper surface, and a male spherical surface can be provided on the lower surface.

DESCRIPTION OF SYMBOLS 10 Press machine 11 Slide 12 Frame 13 Crankshaft 14 Connecting rod 14a (Connecting rod) main body 14b Ball member 15 Main gear 16 Male spherical surface r1 Curvature radius 16a Pin 17 Worm wheel 17a Female spherical surface 17b Vertical groove 17c Teeth 18 Retainer 20 Stick release device 21 receiving seat 21a guide groove 21b void 22 wedge 23 operating mechanism 24 female cylindrical surface r2 radius of curvature 25 female spherical surface 26 male cylindrical surface P1 (spherical) center P2 (cylindrical surface) axis C1 (through center P1) vertical Line C2 (through axis P2) Vertical plane e Offset amount T Thickness 28 Slide member 29 Pin 30 Ball socket joint 31 Ball 32 Socket 33 Female screw 34 Cap screw 34a Shaft portion 35 Collar 36 Head portion 36a Jaw lower surface 37 Stopper 38 Through Through hole

Claims (4)

A stick release device provided at a connecting portion between a connecting member and a slide,
A male curved surface provided at a lower end of the connecting member and having a first radius of curvature;
A female curved surface provided on the slide, having a second radius of curvature greater than the first radius of curvature, and decentered from the male curved surface;
A wedge having a concave surface slidably contacting the male curved surface and a convex surface slidably contacting the female curved surface;
A stick releasing device for a press machine, comprising: a moving means for moving the wedge from a state where a thick portion is interposed between a male curved surface and a female curved surface to a state where a thin portion is interposed.   2. The stick releasing device according to claim 1, wherein the male curved surface of the connecting member and the concave surface of the wedge abutting thereon are spherical.   2. The stick releasing device according to claim 1, wherein the female curved surface of the slide and the convex surface of the wedge that contacts the female curved surface are cylindrical surfaces.   The stick releasing device according to claim 1, wherein the moving unit includes a screw mechanism that converts a rotation operation into an operation of moving a wedge.

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