JP2005279746A - Punching unit structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a punching unit structure which allows miniaturization of a punching unit and reduction of the bending moment on a cramp. <P>SOLUTION: The punching unit structure is equipped with a punch 2 with a thread part 12 formed on the outer circumference, a nut 15 which is screwed onto the thread part 12 of the punch 2 and in which a projection 14 extending downward is formed at the radial direction inside part, a cramp 16 which is fitted to the outer circumference of the projection 14 of the nut 15 and which presses the nut 15 to the punch 2, and an elastic member 6 which is arranged so as to be abutted on the lower face of the cramp 16 and which presses upward the cramp 16, the nut 15 and the punch 2, wherein for the cramp 16, an extended part 22 projecting inward radially from the lower end of the cramp and covering at least a part of the lower face of the projection 14 is formed, and the elastic member 6 is arranged so as to be abutted on at least a part of the lower face of the extended part 22 for the cramp 16. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a punching unit structure including a nut screwed into a punch and a clamp for tightening the nut.

  Conventionally, a turret punch or the like has been used for drilling a product such as a flat plate, a shape steel, or a shape having a free-form surface. The turret punch has a punching unit composed of a punch mounted on the upper mold and a die mounted on the lower mold. By the punching unit, processing of products having a material such as metal or non-metal is performed. Is done.

  As shown in FIG. 3, the punching unit 1 includes a punch 2 composed of a plurality of substantially cylindrical members that are vertically continuous, and a die 8 disposed below the punch 2 with a gap between the punch 2 and the punch 2. In addition, a product 29 to be processed is disposed between the punch 2 and the die 8. The upper part of the punch 2 is screwed into the punch head 4 and inserted from the lower end to the center part of the punch 2 into the cylindrical punch guide 5 so as to be slidable in the vertical direction. Further, an elastic member 6 that provides strip pressure to the punch guide 5 is provided between the punch head 4 and the punch guide 5. The punch head 4 to be screwed with the punch 2 includes a nut 15 provided with a slit (not shown) that is vertically divided (divided into right and left in FIG. 3), and a fixing screw 36. The punch 2 is screwed onto the nut 15, and a slit (not shown) of the nut 15 is tightened with the fixing screw 36, whereby the screwed portion between the punch 2 and the nut 15 is prevented from rotating.

  Then, an impact force is applied downward from the top of the nut 15 with a hydraulic cylinder (not shown), and the product 29 is sandwiched between the punch 2 and the die 8 to perform processing such as drilling.

  However, in the structure in which the rotation is prevented by such a fixing screw 36, when the product 29 is thick and the punching impact force is large or the number of times of punching is increased, the fixing screw 36 is caused by the punching impact force. Is loosened, and a large stress is generated at the threaded portion between the punch 2 and the nut 15. Due to the large stress, the punch 2 and the fixing screw 36 of the punch head 4 are damaged.

  In order to solve this problem, there is a punching unit structure as shown in FIG. A punch head 4 having a punching unit structure shown in FIG. 4 includes a nut 15 having a cylindrical protruding portion 14 protruding downward from a center portion of a lower surface, and a ring-shaped clamp 16 fitted to the outer peripheral portion of the protruding portion 14. With. A female screw portion 18 is formed on the inner peripheral side surface of the projecting portion 14 so as to extend in the vertical direction and to screw the punch 2. The outer peripheral side surface of the protrusion 14 has a taper that decreases downward and the outer diameter decreases, and the inner peripheral side surface of the ring-shaped clamp 16 has a taper that increases upward and the inner diameter increases. Further, the elastic member 6 is disposed so as to contact the lower surface of the clamp 16.

  In the punching unit structure shown in FIG. 4, an upward force in the axial direction (vertical direction in FIG. 4) is applied from the elastic member 6 to the clamp 16 so that the clamp 16 moves upward along the protruding portion 14 of the nut 15. A sliding force is applied to the protrusion 14 in the radially inward direction. Accordingly, the punch 2 and the nut 15 are prevented from rotating, and damage to the punch 2 and the nut 15 due to punching impact force can be prevented (see Patent Document 1).

No. 7-50024

  Thus, in order to slide the clamp 16 upward and obtain the effect of detent, it is necessary to make only the upper surface of the elastic member 6 and the lower surface of the clamp 16 abut.

  However, in the punching unit structure shown in FIG. 4, if only the upper surface of the elastic member 6 and the lower surface of the clamp 16 are brought into contact with each other, a useless gap corresponding to the thickness of the protrusion is provided between the punch 2 and the elastic member 6. Will occur.

  As a result, if the outer diameter of the punching unit 1 is kept at a predetermined dimension, the cross-sectional area of the elastic member 6 becomes small, the stripper pressure necessary for punch punching is insufficient, and the punch 2 such as a pierce punch is made into a product. This may cause a phenomenon that the adhesive 29 does not peel off, causing problems such as the production being impossible.

  On the other hand, in order to secure a sufficient stripper pressure, it is necessary to increase the outer diameter of the elastic member 6 and the outer diameter of the punching unit 1 is increased. As a result, the mass of the punching unit 1 increases, and the impact force applied to the punch 2 and the nut 15 increases.

  Further, as shown in FIG. 4, an upward force F1 from the elastic member 6 and a downward force F2 from the nut 15 are applied to the clamp 16 at the time of punching, and a bending moment M is generated by these forces F1 and F2. However, in the punching unit structure shown in FIG. 4, since there is a gap between the elastic member 6 and the punch 2, the distance between the site where the force F1 is applied and the site where the force F2 is applied in the clamp 16 is long. Accordingly, the bending moment applied to the clamp 16 is increased.

  Accordingly, an object of the present invention is to provide a punching unit structure capable of solving the above-described problems, reducing the size of the punching unit 1 and reducing the bending moment M applied to the clamp 16.

  The invention according to claim 1 for achieving the above object includes a punch having a threaded portion formed on an outer peripheral portion, and a projecting portion that is screwed with the threaded portion of the punch and extends downward to a radially inner portion. A nut formed on the outer periphery of the projecting portion of the nut, and a clamp that presses the nut against the punch, and is disposed in contact with the lower surface of the clamp, the clamp, In the punching unit structure provided with an elastic member for urging the nut and the punch upward, an extension portion that protrudes radially inward from the lower end portion and covers at least a part of the lower surface of the protrusion portion is formed on the clamp The elastic member is disposed in contact with at least a part of the lower surface of the extension portion of the clamp.

  The invention according to claim 2 for achieving the above object is characterized in that the extension portion of the clamp is formed so as to cover the entire lower surface of the protruding portion of the nut, and the elastic member is formed of the clamp. It arrange | positions so that it may contact | abut to the radial direction inner side part of the lower surface of the said extension part.

  According to a third aspect of the invention for achieving the above object, the elastic member is a spring.

  According to the present invention, the following excellent effects are exhibited.

  (1) By placing the elastic member close to the punch, the punching unit can be reduced in weight and size.

  (2) The bending moment applied to the clamp can be reduced by bringing the contact surface of the clamp with the elastic member close to the axial center of the punch.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  Fig.1 (a) shows sectional drawing of the punching unit structure of this embodiment, FIG.1 (b) shows the top view of the nut of this embodiment. Fig.2 (a) shows the elements on larger scale of IIa of FIG.

  In this embodiment, the punching unit structure of the present invention is applied to an apparatus for punching an iron plate or a non-ferrous structure with a punch attached to an upper die and a die attached to a lower die. 1 and FIG. 2 (a).

  The schematic structure of the punching unit structure of the present embodiment is the same as that shown in FIGS. 3 and 4, and the same elements are denoted by the same reference numerals.

  The punching unit 1 of the present embodiment includes a punch 2 composed of cylindrical members having different diameters that are continuous in the axial direction (the vertical direction in FIG. 1), a punch head 4 attached to the top of the punch 2, and the punch 2. A punch guide 5 into which a central portion is inserted from the lower end of the punch, a spring 6 which is an elastic member disposed so as to surround the punch 2 between the punch head 4 and the punch guide 5, and below the punch 2, A punch 2 and a die 8 disposed with a predetermined gap are provided.

  The die 8 is mounted on a lower mold (not shown), and the punch head 4 and the punch guide 5 are attached to an upper mold (not shown).

  The punch 2 is composed of a plurality of substantially cylindrical members having the same center, and the punch 2 is located at the lower part of the punch 2, the blade portion 9 facing the die 8, and the central portion of the punch 2 from the top of the blade portion 9. A substantially cylindrical body portion 10 having a larger diameter than the blade portion 9 and a substantially cylindrical neck portion 11 extending from the top of the body portion 10 to the upper end of the punch 2 and having a smaller diameter than the body portion 10. With.

  In this embodiment, the blade tip shape of the blade part 9 is formed in a circular shape, for example. In addition, the blade edge shape of the blade portion 9 is formed in various shapes such as a cross shape and a star shape in accordance with the purpose of punching. A male thread is cut in the outer peripheral part from the upper end of the neck part 11 to the center part, and the thread part 12 is formed.

  The punch head 4 includes a ring-shaped nut 15, and a substantially cylindrical protruding portion 14 that protrudes downward is formed on the radially inner portion of the lower surface of the nut 15. The punch head 4 includes a substantially cylindrical clamp 16 that is fitted to the outer peripheral portion of the protruding portion 14 of the nut 15.

  On the inner peripheral side surface of the nut 15, a female screw portion 18 to which the screw portion 12 of the punch 2 can be screwed is formed over the entire area. That is, the female screw portion 18 is formed from the lower end portion of the protruding portion 14 to the upper end portion of the nut 15. Further, as shown in FIG. 1B, the nut 15 has a slit 19 having a predetermined width that extends from the outer peripheral end of the ring-shaped nut 15 beyond the center in the radial direction and divides the protruding portion 14 into two vertically. It is formed. In the present embodiment, the length of the slit 19 is about 5/6 of the diameter of the nut 15, but the present invention is not limited to the width and length of the slit 19 and the presence or absence of the slit 19. A clearance hole 20 is formed at the end of the slit 19. Further, the outer peripheral side surface of the protruding portion 14 of the nut 15 is formed in a tapered shape such that the outer diameter increases from the lower end portion toward the upper end portion.

  A through hole 21 is formed at the center of the clamp 16 so as to extend in the vertical direction and into which the protruding portion 14 of the nut 15 is inserted. The inner peripheral side surface of the through hole 21 is formed in a taper shape such that the inner diameter decreases from the upper end portion toward the lower end portion, and further, at the lower end portion of the clamp 16 (through hole 21), radially inward. A protruding extension 22 is formed. The extension 22 has a length such that the inner diameter of the through hole 21 narrowed by the extension 22 is equal to the inner diameter of the protrusion 14 of the nut 15. That is, the extension 22 covers the entire lower surface of the protrusion 14 and is disposed without a gap from the neck 11 of the punch 2.

  The punch guide 5 includes a substantially cylindrical guide portion 24, a stripper portion 25 formed at the lower end of the guide portion 24, and a ring-shaped punch guide fastener 26 attached to the upper end of the guide portion 24. The inner peripheral side surface of the guide portion 24 is formed so as to contact the outer peripheral side surface of the body portion 10 of the punch 2 over the entire circumference so that the body portion 10 can slide in the vertical direction. Further, the upper end portion of the guide portion 24 extends radially outward, and the upper surface of the extended portion comes into contact with the lower surface of the punch guide fastener 26. The stripper portion 25 extends radially inward from the lower end portion of the guide portion 24, and the end surface of the extended portion comes into contact with the side surface of the blade portion 9 of the punch 2. The neck 11 of the punch 2 is inserted into the ring-shaped punch guide fastener 26. Further, a convex portion 28 that protrudes downward and is inserted into the guide portion 24 is formed on the lower surface of the punch guide fastener 26.

  The spring 6 is a coil spring, for example, and is arranged with the upper surface of the spring 6 in contact with the lower surface of the clamp 16. Furthermore, in the present embodiment, the spring 6 is arranged with the radially inner side of the spring 6 aligned with the radially inner side of the extension 22 of the clamp 16. The inner diameter of the spring 6 is substantially equal to the outer diameter of the neck 11 of the punch 2, and the cross-sectional area of the spring 6 is a cross-sectional area that provides a desired strip pressure, that is, the punch guide 5 presses the product 29 during punching. 2 is a cross-sectional area in which the spring 6 has a minimum repulsive force necessary to prevent the product 29 from adhering to the spring 2. Further, the length of the spring 6 is regulated by the length of the neck portion 11 of the punch 2.

  Thus, since the length of the spring 6 is regulated, the repulsive force of the spring 6 is adjusted only by the cross-sectional area of the spring 6, and the cross-sectional area of the spring 6 is determined by a desired strip pressure. Further, the inner diameter of the spring 6 is determined according to the outer diameter of the neck portion 11 of the punch 2, and the outer diameter of the spring 6 is determined by the inner diameter and the cross-sectional area. The outer diameter of the punching unit 1 such as the punch head 4 and the punch guide 5 is determined by the outer diameter of the spring 6.

  Next, the operation of the punching unit structure of this embodiment will be described.

  A spring 6 is fitted to the neck 11 of the punch 2, and a clamp 16 is fitted so as to sandwich the spring 6 with the punch guide 5.

  From this state, the screw portion 12 of the punch 2 is lightly screwed into a predetermined position in the protruding portion 14 of the nut 15, and then a clamp 16 is fitted on the outer periphery of the protruding portion 14 of the nut 15.

  Further, a product 29 is set between the punch 2 and the die 8 and an impact force is applied to the top of the nut 15 by a hydraulic cylinder (not shown).

  When an impact force is applied, the punch guide 5 is lowered until it comes into contact with the product 29 by the action of a lifting mechanism (not shown), and then the punch 2 is lowered while being guided in the punch guide 5.

  When the punch 2 is lowered, the spring 6 is sandwiched between the punch head 4 and the punch guide 5 and bent. Due to the repulsive force of the spring 6, the clamp 16 is pushed upward in the axial direction, and the slit 19 of the nut 15 portion is narrowed. Thereby, a strong radial compressive force is applied to the threaded portion 12 of the punch 2 and the internally threaded portion 18 of the nut 15. Such a rotation stop by the clamp 16 is made at the time of the first punching, and has a structure that can withstand the impact force of punching.

  Thus, in order to obtain the anti-rotation effect, the axially upward pressure is applied to the bottom surface of the clamp 16 from the spring 6, and the inner peripheral side surface of the clamp 16 is projected from the protruding portion 14 of the nut 15. The reaction force of is added. As shown in FIG. 1, a bending moment M is generated in the clamp 16 by the upward force F1 from the spring 6 and the downward component force F2 of the reaction force from the nut 15. In the punching unit structure of the present embodiment, the spring 6 is arranged close to the punch 2, so that the contact surface of the clamp 16 with the spring 6 (site where the force F <b> 1 acts) and the nut 15 of the clamp 16 are fixed. The distance in the radial direction between the contact surface with the protrusion 14 (where the force F2 is applied) is shortened, and the bending moment applied to the clamp 16 due to the impact force during punching is suppressed.

  After the product 29 is punched, the bent spring 6 is restored and the punch 2 is raised to a predetermined position by the spring 6. When the punch 2 is raised, the spring 6 presses the stripper portion 25 of the punch guide 5 against the product 29 to prevent the product 29 from adhering to the punch 2. After the punch 2 is raised, the punch guide 5 is raised by the action of a lifting mechanism (not shown).

  As described above, in the punching unit structure according to this embodiment, the extension portion 22 that covers the protruding portion 14 of the nut 15 is provided at the lower end portion of the clamp 16, and the spring 6 is brought into contact with the lower surface of the extension portion 22. By arranging, that is, by reducing the inner diameter of the spring 6 having a predetermined cross-sectional area, the outer diameter of the spring 6 can be reduced and the diameter can be reduced. Furthermore, by reducing the diameter of the spring 6, the punch head 4, the punch guide 5, and the like can be reduced in diameter, and the punching unit 1 can be reduced in weight and size. Further, by reducing the weight of the punching unit 1 and reducing the mass, impact energy during punching can be reduced, and the stress applied to the screw portion 12 of the punch 2 and the female screw portion 18 of the nut 15 can be reduced. Furthermore, by reducing the size of the punching unit 1, it is possible to reduce the size of the apparatus to which the punching unit 1 is attached.

  By bringing the contact surface of the clamp 16 with the spring 6 close to the contact surface of the clamp 16 with the protrusion 14 of the nut 15, the bending moment M applied to the clamp 16 can be reduced. Further, since the bending moment M applied to the clamp 16 is reduced, the reliability of the punching unit 1 or the like can be improved. Furthermore, since the bending moment M applied to the clamp 16 is reduced, the thickness of the clamp 16 and its material can be changed, and the cost of the punching unit 1 can be reduced.

  When the punch 2 is screwed into the nut 15 provided with the slit 19 and the slit 19 is tightened by the clamp 16, the punch 2 and the nut 15 are not loosened during punching, and the punch head 4 and the punch 2 are damaged. Can be prevented.

  In the present embodiment, as shown in FIG. 2 (a), the throat portion 30 of the protrusion 14 formed on the clamp 16 is formed in a right-angle shape, but the present invention is not limited to this, and FIG. 2 (b). As shown in FIG. 3, the throat base portion 30 of the protruding portion 14 may be provided with an inclined shape, or the throat base portion 30 may be provided with a round shape.

  The punching unit structure of the embodiment shown in FIG. 2 (b) can achieve the same effect as the punching unit structure of the embodiment shown in FIG. 1, and can further reduce the stress concentration applied to the protrusion 14 of the clamp 16. effective.

  In this embodiment, the elastic member 6 is a coil spring. However, the elastic member 6 is not limited to this and may be a disc spring, a urethane spring, or the like.

(A) shows sectional drawing of the punching unit structure which concerns on this invention, (b) shows the top view of the nut of the punching unit structure which concerns on this invention. (A) shows the IIa partial enlarged view of FIG. 1, (b) shows the figure corresponded to FIG. 2 (a) in other embodiment. Sectional drawing of the conventional punching unit structure is shown. Sectional drawing of the other conventional punching unit structure is shown.

Explanation of symbols

1 Punching unit 2 Punch 6 Spring (elastic member)
12 Thread part 14 Projection part 15 Nut 16 Clamp 22 Extension part

Claims (3)

  A punch having a threaded portion formed on the outer periphery, a nut threadedly engaged with the threaded portion of the punch, and a projecting portion extending downward on the radially inner portion, and an outer periphery of the projecting portion of the nut And a clamp that presses the nut against the punch, and an elastic member that is disposed in contact with the lower surface of the clamp and biases the clamp, nut, and punch upward. In the punching unit structure, the clamp is formed with an extension projecting radially inward from a lower end thereof to cover at least a part of the lower surface of the projection, and the elastic member is used as a lower surface of the extension of the clamp. A punching unit structure characterized by being disposed in contact with at least a part of the punching unit.   The extension of the clamp is formed so as to cover the entire lower surface of the protrusion of the nut, and the elastic member is in contact with the radially inner portion of the lower surface of the extension of the clamp. The punching unit structure according to claim 1, which is arranged. 3. The punching unit structure according to claim 1, wherein the elastic member is a spring.

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