JP3006747B2 - Extrusion press - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of extruding a billet by an extrusion press of an aluminum alloy or the like, wherein air between the container and the billet is discharged outside the container before the billet is extruded from a container through a die. The present invention relates to an extrusion press that mechanically closes an air vent of a container side connected to a vacuum pump while discharging the air to a vacuum pump.

[0002]

2. Description of the Related Art After a billet having a diameter slightly smaller than the inner diameter of a container is placed in the container, the billet is pushed by a stem at the back of the billet and pressed against a die in a container. The air between them is compressed. In order to release the compressed air, the stem and the container are slightly retracted, the compressed air is removed from the gap between the die and the container, and the container and the stem are advanced again to start extrusion. The degassing step of removing the compressed air in this manner is called a burp cycle, but the presence of this step causes a waste of time in the extrusion cycle.

[0003]

However, in order to eliminate the dead time due to the conventional burp cycle, if an attempt is made to remove residual air from the tip of the container on the die side by means of a vacuum pump, the space between the inner surface of the container and the outer surface of the billet is reduced. The air remains at atmospheric pressure in a thin state of about one skin, and sufficient degassing has not been performed. Further, aluminum chips often adhere to the end faces of the container liner and the die. If it adheres to a uniform film, there should be no air infiltration at the time of sealing.However, in general, if the debris adheres unevenly, the container seal between the container liner end face and the die end face will be insufficient due to the adhesion of these debris. There is a problem that burrs are generated because the burrs cannot be formed and the growth of the burrs adversely affects the operation of the seal ring mechanism.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an extrusion press capable of easily removing attached burrs.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and has a piston in an annular recess at the die-side end surface of an extrusion container.
A plurality of air actuators that can supply and discharge air later to move the piston back and forth are arranged, and the air actuator is integrally arranged outside the die side of the air actuator and the die side end face and in the pushing direction. A seal ring for opening and closing the deaeration port by contacting and separating is provided on the end face of the container.

[0006]

When the billet in the container is pushed by the stem behind the billet and the billet is pressed against the die, the billet is crushed and the air between the container and the billet is compressed. This compressed air must be exhausted before the billet is extruded from the die. In the present invention, immediately after the billet is compressed by the stem and the extruded material is extruded from the die, the seal ring is drawn in from the container end face by the air actuator integrally provided with the seal ring, thereby forcing the deaeration port outlet. As the burr is grown, the outlet of the deaeration port is not blocked by the grown burr, and the burr is easily removed. When air is sucked from the die side of the container, the seal ring engaged with the container tip and movable in the axial direction is sealed with the container-side end surface of the die ring.
The air is sucked through the minute gap between the die and the container. Immediately before the upset is completed, the container is advanced to the die side, and the leading end surface of the container is pressed against the die, so that the minute gap is eliminated.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is a sectional view showing an embodiment of a deaerator for an extrusion container according to the present invention, FIG. 2 is a front view as viewed from A to A in FIG. 1, and FIG. 3 is a main part showing a state before the start of billet extrusion. FIG. 4 is an enlarged cross-sectional view, FIG. 4 is an explanatory view showing a state in which the seal ring is retracted from the container end face, and FIG. 5 is a conceptual view showing how a billet pressed in the container is crushed.

A main part of a part B on the piston head side of a container cylinder 33 which is mounted on the end platen 32 of FIG. 1 and slides the container tire 2 and the container 1 is a moving stopper block 34 and a head block 35 which also serves as a stopper.
At the maximum distance within the range in which the movement stopper block 34 moves, the piston 37 is temporarily stopped so that the end surface of the container 1 on the die 3 side can be rapidly stopped with a gap of, for example, about 2 to 3 mm from the die 3 surface. Mechanism 30
It has a structure having. In FIG. 1, reference numeral 36 denotes a cylinder tube constituting a part of the cylinder body, 35 denotes a head block at the rear of the cylinder body, 37 denotes a piston, 3
8 is a piston rod.

Reference numeral 3 denotes a die, and the outer periphery of the die 3 is slidably fitted and held on the inner peripheral surface of the die ring 5. Numeral 6 is a gap, and a gap 6 of, for example, 2 to 3 mm is provided between the container 1 and the die 3 or the die ring 5 by a temporary stop mechanism provided in the container cylinder 33. Reference numeral 31 denotes a gap between the inner peripheral surface of the container and the outer peripheral surface of the billet 13, which is also a degassing space.

On the other hand, the extrusion stem 1 for pushing the billet 13
A fixed dam block 15 that can be in close contact with the inner surface of the container 1 is provided at the tip of the container 4. The fixed damage block 15 is a rear member 17 of a dummy block which is fixed to a distal end of a tubular member 16 fixedly provided on a shaft portion in the extrusion stem 14 by screws, and an outer peripheral portion of the distal end of the rear member 17 is screwed. An outer ring 18 that is attached and whose distal end portion can expand in the outer diameter direction and can come into close contact with the inner peripheral surface of the container 1. 14a is a stem holder, 14b
Is a crosshead.

In this embodiment, as shown in FIG. 3, an annular recess 24 concentric with the container 1 is formed on the end face of the container tire 2 on the die 3 side. Are arranged at equal intervals (16 in this embodiment). The seal ring 11 concentric with the container 1 is fixed to the rod 25a of the air actuator 25, and the seal ring 1 is moved in the forward and backward directions of the piston 25b of the air actuator 25.
1 is provided so as to be able to move forward and backward in the extrusion direction.

The seal ring 11 is pressed against the die 3 by the forward and backward movement of the piston 25b to open and close the deaeration port outlet 40 communicating with the deaeration space 31. The residual air in the container 1 sucked through the deaeration port outlet 40 is sucked and discharged from a deaeration duct 8 provided on the seal ring 11.

On the container 1 side of the annular concave portion 24,
A spring 26 is elastically mounted between the seal ring 11 and the annular concave portion 24, and is configured to constantly extend the seal ring 11 toward the die 3.

There are two slit-shaped deaeration holes 7 as shown in FIG. 2 above the seal ring 11, from which they are connected to a vacuum tank 20 and a vacuum pump 21 via a duct 8 and an electromagnetic switching valve 9. ing. 22 is a motor.

Next, the operation of the extrusion press will be described. First, the die-side end surface of the container 1 is stopped in a state in which there is a gap 6 of, for example, about 2 to 3 mm with the die ring 5 surface. In this state, the billet 13 is loaded into the container 1 by the forward movement of the extrusion stem 14, and the tip surface of the billet 13 is applied to the die 3. This state is shown in FIG. At this time, air is present in the degassing space 31 between the container 1 and the billet 13.

At the same time, for example, compressed air or the like is introduced into the head side of the piston 25b of the air actuator 25 to advance the piston 25b to separate the seal ring 11 from the end face of the container tire 2 and open the deaeration port outlet 40. State (FIG. 4 (1)).

When this operation is completed, the billet 13
The billet loader (not shown) rises with
When the extrusion stem 14 is advanced, the billet 13 is pushed into the container 1 and the billet 13 comes into contact with the die 3 side end surface. Further, the extrusion stem 14 advances to start upset. If this state is continued, the air in the deaeration space 31 is sucked from the die 3 side by the action of the vacuum tank 20 when the billet 13 on the extrusion stem 14 side comes into close contact with the container 1. At this time, the sucked air on the side of the die 3 passes through the gap 6, passes through the deaeration hole 7 provided in a part of the seal ring 11 attached to the container 1, and then passes through the duct 8 to the upper surface of the container 1 through the duct 8. It is led to the electromagnetic switching valve 9.

The piping between the vacuum tank 20 and the electromagnetic switching valve 9 is previously evacuated to, for example, 5 to 10 torr. When the billet 13 comes into contact with the die 3, the electromagnetic switching valve 9 opens and the seal ring 11 is closed. The deaeration space 31 is quickly and sufficiently deaerated through the deaeration hole 7. Extrusion stem 1
4 moves forward without a break, and the billet 13 is crushed. FIG. 5 shows the crushed state. In these figures, the degassing space 31 between the container 1 and the billet 13 is formed by the extrusion stem 14 and the billet 13 is moved from S ₁ to S ₁ in the die direction.
_It can be seen from FIG. 5 that if the pressure is sequentially increased to ₃ , the degassing space 31 is pressed toward the die. Degassing can be performed, for example, at a degree of vacuum of about 10 to 50 torr in about 0.5 seconds.

After the suction and deaeration starts, the extrusion stem 14
Keeps moving forward without a break and crushes billet 13. Then, the billet 13 is filled in the container 1, and when the upset is completed, the deaeration port outlet 40 by the vacuum pump 21
The suction of the residual air from the container 1 is stopped, and the end face of the container 1 is retracted by α as shown in FIG.

Next, the extrusion is continued, and the product is extruded from the die 3. When the degassing space 31 inside the container 1 reaches a predetermined degree of vacuum, the container 1 advances to the die 3 side, and the end surface of the container 1 on the die 3 side hits the die 3 surface, and the container 3 contacts the die 3 surface. The gap 6 is set to zero, and deaeration is continued until immediately after the start of extrusion.

When the billet 13 is repeatedly extruded in this manner, the residue adheres unevenly to the end face on the container tire 2 side,
When the container seal becomes insufficient, burrs may be generated. However, since the front end face of the seal ring 11 is retracted by α from the end face of the container 1 on the die 3 side, the intrusion of burrs is prevented. At the same time, burrs can be easily removed.

[0022]

As is apparent from the above description, in the present invention, a piston is provided inside the annular concave portion on the die side end surface of the extrusion container, and air is supplied before and after the piston.
A plurality of air actuators capable of feeding and discharging the piston and moving the piston back and forth are arranged, and the air actuator is integrally disposed outside the die side of the air actuator and is separated from the die side end face in the pushing direction. By providing a seal ring for opening and closing a deaeration port on the end face of the container, even if a blossoming phenomenon of burr occurs at the start of extrusion, burr can be easily removed, so continuous extrusion becomes possible, and productivity is significantly improved. . In addition, since container replacement can be completed simply by removing the coupler of the duct connected to the actuator, the operation can be completed in a short time and easily.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of an extrusion molding method according to the present invention.

FIG. 2 is a front view as viewed from A to A in FIG. 1;

FIG. 3 is an enlarged sectional view of a main part showing a state before the start of billet extrusion.

FIG. 4 is an explanatory view showing a state where a seal ring is drawn in from a container end face.

FIG. 5 is a conceptual diagram showing how a billet pressed in a container is crushed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Container tire 3 Dice 6 Gap 7 Deaeration hole 8 Duct 11 Seal ring 13 Billet 14 Extrusion stem 14b Crosshead 15 Fixed dam block 20 Vacuum tank 21 Vacuum pump 24 Annular concave 25 Air actuator 25a Rod 25b Piston 26 Spring 30 Temporary stop mechanism 31 Deaeration space 32 End platen 33 Container cylinder 37 Piston 40 Deaeration port outlet

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B21C 27/04

Claims (1)

(57) [Claims] 1. A piston is provided in an annular concave portion on the die side end surface of an extrusion container, and air is blown before and after the piston.
A plurality of air actuators capable of feeding and discharging the piston and moving the piston back and forth are arranged, and the air actuator is integrally disposed outside the die side of the air actuator and is separated from the die side end face in the pushing direction. An extrusion press, wherein a seal ring for opening and closing a deaeration port is provided on the end face of the container.