JP4798060B2 - Forging die - Google Patents

Description

  The present invention relates to a structure of a forging die, and more particularly to a technique for removing powdery foreign matters such as chips generated during forging from the die.

A forging technique in which a forging machine such as a hammer or a press is attached to a pair of upper and lower forging dies, a blank (heated or cold material) is placed in the mold, and molding is performed by compression. Are known. Parts such as bolts and nuts are processed by this die forging technique.
In die forging as described above, chips generated by cutting a blank during forging adhere to a forging die or blank. In this way, when forging is performed in a state where the chips are attached to the forging die, the slippage of the mold may be defective due to the chips. Moreover, the shape accuracy of the forged product has been lowered by forging with the chips adhering to the blank.

  Therefore, the chips adhering to the forging die are removed by air blow every time the die is opened in the forging process. However, with air blow, it is possible to disperse the chips, but the chips cannot be collected and remain in the mold and prevent the chips generated by processing from being caught in the forged product. In addition, there is an inconvenience that it cannot be performed, and it is necessary to appropriately change the place where the air abuts according to the shape of the mold.

  Further, in Patent Document 1, a slit for ventilation is provided on the mating surface of the forging die, and the slit is communicated with the outside through a discharge hole opened on the front surface of the holding case, and high pressure fluid is supplied to the slit. Thus, a technique has been proposed in which foreign matter such as air and metal fines generated in the mold is positively discharged to the outside of the mold.

As described in Patent Document 1, by constantly supplying high pressure fluid into the mold, foreign matter such as chips can be removed, but noise generated by high pressure fluid supply means such as an air compressor is generated. The work environment will be greatly impaired. Further, in the technique described in Patent Document 1, in the case of a closed upset forging die, the blank is completely sealed and installed in the inside of the die, so that the molds in the clamped state are aligned. There is an inconvenience that the foreign matter cannot be removed from the surface.
Japanese Utility Model Publication No. 6-70936

  In view of the above prior art, the present invention proposes a technique for discharging powder-like foreign matters such as chips generated by forging on the mating surface of the movable mold and the fixed mold in the forging mold. Thus, processing defects due to the foreign matter adhering to the blank or forging die are reduced.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in claim 1 , a fixed mold and a movable mold that can move forward and backward with respect to the fixed mold are provided, and a forged product is obtained by forging a blank at a molding portion provided on these mating surfaces. A forging die, an intake reservoir provided in the movable mold, a forced exhaust means for forcibly exhausting the intake reservoir to create a negative pressure, and a mating surface of the intake reservoir and the movable mold A suction hole formed in the movable mold so as to open, and a suction valve provided in the suction hole, opened along with the moving movement of the movable mold, and closed with the retracting movement of the movable mold Are provided.

According to claim 2 , forging for obtaining a forged product by forging a blank at a molding portion provided on a mating surface of the stationary die and a movable die movable forward and backward with respect to the stationary die. A mold, an intake reservoir provided in the movable mold, a forced exhaust means for forcibly exhausting the intake reservoir, a small-diameter hole opening in the mating surface of the movable mold, and an opening in the intake reservoir And a valve seat formed between the small-diameter hole and the large-diameter hole, and is formed in the movable mold substantially parallel to the advancing / retreating direction of the movable mold. Formed between the suction hole, the small diameter shaft portion slidable in the small diameter hole portion, the large diameter shaft portion movable in the large diameter hole portion, and the small diameter shaft portion and the large diameter shaft portion. A valve that can be seated on the valve seat, and when the valve is seated on the valve seat, the end of the small-diameter shaft portion is more than the movable mating surface. As a state of projecting to the fixed mold side, said suction holes to be inserted the valve body, and a biasing means for biasing the valve element to the fixed mold side, but with.

According to a third aspect of the present invention, in the forging die according to the first or second aspect , the movable die is provided with a suction hole for communicating the intake reservoir and the molding portion of the movable die.

  As effects of the present invention, the following effects can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, powdery foreign materials, such as a chip produced by a forging process, can be discharged | emitted to the exterior of a metal mold | die at the mating surface of the movable mold | type of a forging metal mold | die, and a fixed mold. Thereby, the processing defect resulting from the said foreign material adhering to a blank or a metal mold | die for forging can be aimed at. Since the discharge of the foreign matter functions only during the forging process, the foreign matter in the mold can be efficiently removed by suction. Furthermore, by communicating the intake reservoir with the movable molding part, powdery foreign matters such as chips generated in the molding part can also be sucked and removed out of the mold.

Next, embodiments of the invention will be described.
FIG. 1 is a view showing a forging machine having a forging die according to an embodiment of the present invention, FIG. 2 is a view showing a forging die in a state in which the suction valve is closed, and FIG. FIG. 4 is an enlarged view showing the structure of the suction valve, and FIG. 5 is a view for explaining the flow of forging.

First, the structure of the forging die 50 according to the embodiment of the present invention will be described.
As shown in FIG. 1, the forging die 50 is used by being attached to a forging machine 60. The forging machine 60 includes a ram 61, a slide 62 that moves back and forth with respect to the ram 61, and a driving means 63 for the slide 62. In this embodiment, a slide 62 is disposed above the ram 61, and the slide 62 reciprocates in a substantially vertical direction.

The forging die 50 includes a movable die 10 attached to the slide 62 and a fixed die 9 fixed to the ram 61. As the slide 62 moves forward and backward relative to the ram 61, the movable mold 10 can move forward and backward with respect to the fixed mold 9.
Here, the movement of the movable mold 10 in the direction approaching the fixed mold 9 is referred to as “advance movement”, and the movement of the movable mold 10 in the direction away from the fixed mold 9 is referred to as “regression movement”.
Hereinafter, the advancing / retreating direction of the movable mold 10 is referred to as a “machining direction”.
A molding part for molding a forged product is provided on the mating surface of the movable mold 10 and the fixed mold 9, and the blank W set in the molding part is sandwiched between the movable mold 10 and the fixed mold 9 and pressed. In particular, a forged product can be obtained.

As shown in FIGS. 2 and 3, a pressure receiving plate 65 that receives pressure during molding is fixed to the ram 61, and a fixed mold 9 is attached to the pressure receiving plate 65, and the fixed mold 9 is attached to the ram 61. It is held by a fixed holder 66.
A molding part for molding a forged product is provided at a substantially central part of the mating surface of the fixed die 9, and a knockout pin 67 is provided at a substantial center of the molding part. The knockout pin 67 is for discharging the forged product fixed to the fixed die 9 after forging, and for restraining the blank W from below during forging.

A pressure plate 53 for pressurizing or receiving forging pressure is fixed to the slide 62, the movable die 10 is attached to the pressure plate 53, and the movable die 10 is a holder 54 fixed to the slide 62. Held at.
The movable mold 10 is composed of a main mold 10a which is a general-purpose part and a telescopic mold 10b fitted into the main mold, and a molding portion is provided in the telescopic mold 10b.

  Further, a punch hole 20 is formed in the machining direction substantially at the center of the movable die 10, and a punch 19 having the machining direction as an axial direction is inserted into the punch hole 20. The punch 19 is for pressurizing the blank W set in the molding part of the movable mold 10 and the fixed mold 9.

The movable mold 10 is provided with an exhaust path (first exhaust path R1) for forcibly discharging gas from the mating surface of the movable mold 10 to the outside through the interior of the movable mold 10.
The first exhaust path R1 includes an intake reservoir 15 provided in the movable mold 10, a forced exhaust means 18 for forcibly exhausting the intake reservoir 15, a mating surface between the intake reservoir 15 and the movable mold 10. It is formed by one or a plurality of suction holes 11 formed in the movable mold 10 so as to open in the middle. That is, in the first exhaust path R1, powdery foreign matters such as chips existing between the mating surfaces of the movable mold 10 and the fixed mold 9 are sucked together with the gas to the intake reservoir 15 through the suction hole 11, It is discharged from the intake reservoir 15 to the outside of the movable mold 10.

  A suction port 16 is opened in the intake reservoir 15, and the suction port 16 is connected to a suction pipe 55 inserted in a holder 54. The suction pipe 55 is connected to the forced exhaust means 18 so that the intake reservoir 15 is always forcedly exhausted to a negative pressure.

  As shown in FIG. 4, the suction hole 11 is formed continuously from the small-diameter hole portion 13 that opens to the mating surface of the movable mold 10 and the small-diameter hole portion 13, and the large opening that opens to the intake reservoir 15. The movable mold 10 includes a diameter hole portion 12 and a valve seat 14 formed between the small diameter hole portion 13 and the large diameter hole portion 12, and substantially parallel to the advancing / retreating movement direction of the movable die 10. Drilled.

  In the suction hole 11, there is provided a suction valve that is opened as the movable mold 10 moves forward and is closed as the movable mold 10 moves backward. The suction valve includes a valve seat 14 provided in the suction hole 11 and a valve 33 provided in a pilot pin 30 inserted in the suction hole 11.

The pilot pin 30 is a shaft-like member that functions as a valve body of the suction valve, and one or more pilot pins 30 are provided in the movable die 10 according to the number of suction holes 11 provided in the movable die 10.
The pilot pin 30 is formed continuously with the small-diameter shaft portion 32 slidable in the small-diameter hole portion 13 and the small-diameter shaft portion 32, and can move within the large-diameter hole portion 12. 31, and a valve 33 formed between the small diameter shaft portion 32 and the large diameter shaft portion 31 and seatable on the valve seat 14. Grooves 34, 34, 34 are formed in the processing direction on the peripheral surface of the small diameter shaft portion 32. A stepped surface at the boundary between the large diameter shaft portion 31 and the small diameter shaft portion 32 is a valve 33.

  When the valve 33 provided on the pilot pin 30 is seated on the valve seat 14, the end of the small-diameter shaft portion 32 protrudes toward the fixed die 9 from the mating surface of the movable die 10. Thus, the small-diameter shaft portion 32 has a length in the machining direction that is larger than the length of the small-diameter hole portion 13. Further, the pilot pin 30 is provided with a biasing means 17 for biasing the pilot pin 30 toward the fixed mold 9 and seating the valve 33 on the valve seat 14. Therefore, the pilot pin 30 comes into contact with the fixed mold 9 before the mating surface of the movable mold 10 when the movable mold 10 advances in the direction of the fixed mold 9.

  In the present embodiment, the urging means 17 is an air cylinder, but a hydraulic cylinder or an elastic body such as a spring or rubber may be employed as the urging means 17. However, the biasing means 17 must be capable of applying a biasing force that does not move the pilot pin 30 due to the negative pressure of the intake reservoir 15.

  In addition to the first exhaust path R1, the movable mold 10 is provided with a second exhaust path R2 for forcibly discharging gas from the molding portion of the movable mold 10 to the outside through the inside of the movable mold. The second exhaust path R2 includes the intake reservoir 15 and a suction hole 21 that is formed in the pressure plate 53 in a direction substantially orthogonal to the machining direction and communicates the intake reservoir 15 and the punch hole 20. The

  In the second exhaust path R <b> 2, powdery foreign matters such as chips present in the molding portion of the movable mold 10 together with the gas, the gap between the outer periphery of the punch 19 and the inner periphery of the punch hole 20, and the suction hole 21. Are sucked up to the intake reservoir 15 and discharged from the intake reservoir 15 to the outside of the movable mold 10.

  Next, the state of the first exhaust path R1 and the second exhaust path R2 during forging will be described.

  As shown in FIGS. 2 and 5A, in the state where the forging die 50 is opened and the blank W is set, the suction valve is closed and the first exhaust path R1 does not function, and the second exhaust Only the path R2 functions, and foreign matter in the molding part of the forging die 50 is discharged through the second exhaust path R2.

  As shown in FIGS. 3 and 5 (b), when the forging process is started and the movable die 10 advances toward the fixed die 9 and the pilot pin 30 starts to contact the fixed die 9, the pilot pin 30 is moved to the fixed die 9. 9 is pressed against the urging force of the urging means 17 to move relative to the movable mold 10, the valve 33 is separated from the valve seat 14 and the suction valve is opened. That is, the suction valve provided in the first exhaust path R1 is opened as the movable mold 10 moves forward. At this time, both the first exhaust path R1 and the second exhaust path R2 function, and foreign matters between the mating surfaces of the movable mold 10 and the fixed mold 9 are discharged out of the mold through the first exhaust path R1. Foreign matter in the molding portion of the forging die 50 is discharged out of the die through the exhaust passage R2.

  As shown in FIG. 5 (c), the mating surface of the movable mold 10 and the mating surface of the fixed mold 9 are in contact with each other. Further, as shown in FIG. 5 (d), the movable mold 10 is moved to the fixed mold 9 up to the bottom dead center. When moving forward, the mating surface of the movable mold 10 and the mating surface of the fixed mold 9 are in close contact with each other, so that the suction valve is opened, but the first exhaust path R1 is the end of the suction hole 11 on the mating surface side. Closed. Therefore, when the mating surface of the movable mold 10 and the mating surface of the fixed mold 9 are in contact with each other, only the second exhaust passage R2 functions, and foreign matter in the molding portion of the forging die 50 is discharged through the second exhaust passage R2. Is done.

When the movable mold 10 moves backward from the fixed mold 9 after pressurizing the blank W as described above, if the mating surface of the movable mold 10 and the mating surface of the fixed mold 9 are separated, the first exhaust path R1 and The second exhaust path R2 functions together, foreign matter between the mating surfaces of the movable mold 10 and the fixed mold 9 is discharged out of the mold through the first exhaust path R1, and the forging mold 50 is discharged through the second exhaust path R2. Foreign matter in the molding part is discharged out of the mold.
When the movable mold 10 moves further backward than the fixed mold 9 and the pilot pin 30 moves away from the fixed mold 9, the valve 33 is seated on the valve seat 14 by the urging force of the urging means 17. That is, the suction valve is closed as the movable mold 10 moves backward. At this time, since the suction valve is closed, the first exhaust path R1 does not function, only the second exhaust path R2 functions, and foreign matter in the molding portion of the forging die 50 is discharged through the second exhaust path R2. Is done.

  As described above, in the forging die 50 according to the embodiment of the present invention, the first exhaust path R1 for forcibly discharging the powdery foreign matter existing between the mating surfaces of the movable die 10 and the fixed die 9. And a second exhaust path R <b> 2 for forcibly discharging the powdery foreign matter present in the molding portion of the movable mold 10. And, through the first exhaust path R1 and the second exhaust path R2, powdery foreign matters such as chips generated by forging on the mating surface of the movable mold 10 and the fixed mold 9 and the molding part are discharged to the outside of the mold. can do. Thereby, reduction of the processing defect resulting from the said foreign material adhering to the blank W or the die 50 for forging can be aimed at.

  The first exhaust path R1 functions only when the pilot pin 30 is in contact with the fixed mold 9. That is, in a state in which forging is not performed, only the second exhaust path R2 functions, and foreign matter in the molding portion of the movable mold 10 is forcibly discharged from the forging die 50, and forging starts. The exhaust path R1 and the second exhaust path R2 function, and in addition to the foreign matter in the molding portion of the movable mold 10, foreign matter generated on the mating surface between the movable mold 10 and the fixed mold 9 from the forging die 50 is also generated. It is forcibly discharged. As described above, since the foreign matter is discharged through the first exhaust passage R1 only during the forging process, the foreign matter in the mold can be efficiently removed by suction.

  Further, the first exhaust passage R <b> 1 includes a space between the outer circumferential grooves 34, 34, 34 of the small diameter shaft portion 32 of the pilot pin 30 and the peripheral surface of the small diameter hole portion 13 of the suction hole 11. That is, the cross section of the first exhaust path R1 is squeezed upstream of the intake reservoir 15. Thereby, a suction force can be effectively generated in the first exhaust path R1.

  Further, the first exhaust passage R1 joins the second exhaust passage R2 in the intake reservoir 15 located downstream of the suction valve, and the first exhaust passage R1 extends from the first exhaust passage R1 from the suction valve to the intake reservoir 15. However, the second exhaust path R2 from the molding part of the movable mold 10 to the intake reservoir 15 has a longer path. With this configuration, in a state where the suction valve of the first exhaust passage R1 is closed, foreign matter is discharged through the second exhaust passage R2, but in a state where the suction valve of the first exhaust passage R1 is opened, Since foreign matter is discharged with priority on the first exhaust path R1, powdery foreign matter such as chips generated by forging can be efficiently discharged out of the mold.

The figure which shows the forging machine which installed the metal mold | die for forging which concerns on one Example of this invention. The figure which shows the metal mold | die for forging in the state where the suction valve was closed. The figure which shows the metal mold | die for forging in the state where the suction valve was opened. The enlarged view which shows the structure of a suction valve. The figure explaining the flow of forging.

R1 First exhaust passage R2 Second exhaust passage 10 Movable type 11 Suction hole 12 Large diameter hole portion 13 Small diameter hole portion 14 Valve seat 15 Intake reservoir 16 Suction port 17 Energizing means 18 Forced exhaust means 19 Punch 20 Punch hole 21 Suction hole 30 Pilot pin (valve)
31 Large Diameter Shaft 32 Small Diameter Shaft 33 Valve 34 Groove 50 Forging Die

Claims (3)

A forging die for obtaining a forged product by forging a blank at a molding portion provided on a mating surface, comprising a stationary die and a movable die capable of moving forward and backward relative to the stationary die,
An intake reservoir provided in the movable mold;
Forced exhaust means for forcibly exhausting the inside of the intake reservoir to create a negative pressure;
A suction hole drilled in the movable mold so as to open to the intake reservoir and the mating surface of the movable mold;
A suction valve provided in the suction hole, opened with the moving movement of the movable type, and closed with the moving movement of the movable type;
Forging die, characterized in that it includes. A forging die for obtaining a forged product by forging a blank at a molding portion provided on a mating surface, comprising a stationary die and a movable die capable of moving forward and backward relative to the stationary die,
An intake reservoir provided in the movable mold;
Forced exhaust means for forcibly exhausting the intake reservoir;
A small-diameter hole opening in the movable mating surface, a large-diameter hole opening in the intake reservoir, and a valve seat formed between the small-diameter hole and the large-diameter hole, A suction hole drilled in the movable mold substantially parallel to the moving direction of the movable mold;
A small-diameter shaft portion slidable in the small-diameter hole portion, a large-diameter shaft portion movable in the large-diameter hole portion, and the valve seat formed between the small-diameter shaft portion and the large-diameter shaft portion. A seatable valve, and when the valve is seated on the valve seat, the end of the small-diameter shaft portion protrudes toward the fixed mold side from the mating surface of the movable mold. A valve body inserted in the suction hole;
Urging means for urging the valve body toward the fixed mold side,
Forging die, characterized in that it includes. In the forging die according to claim 1 or 2,
A forging die , wherein the movable die is provided with a suction hole for communicating the intake reservoir and the movable mold forming portion .

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