JPH07323329A - Method and device for cutting off discard part in extrusion press - Google Patents

Abstract

PURPOSE:To surely and easily obtain a cutting-off surface having good smoothened surface without bending of cutting part and roll over of an entrance hole by cutting off a discard part as the extrusion remained part of a billet by using a shearing edge at the front side of a die, after extrusion and retreating a container while separating from the die. CONSTITUTION:When the extrusion completes, the container 7 is retreated while separating from the die 2, and after exposing the discard part in the air, a tilting shearing device 10 with die pushing mechanism for cutting off the discard part is acted to cut off the discard part with the two-step constitution shearing edge 14. At this time, a guide device 15 and the shearing edge 14 are descended in the condition of acting a pushing device 16. Then, since the die 2 is pushed in the extrusion direction with the action of the guide device 15 and the shearing edge 14 is in the condition of pushing to the front surface side of the die, too, a clearance between the front surface of the die and the shearing edge is held to the preset side and the good cutting-off is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, in an extrusion press for a metal such as an aluminum alloy, after the container is retracted from the die after extrusion, the discard, which is the extruded residue of the billet, is placed on the front side of the die. The present invention relates to a discarding method and apparatus for cutting with a shear blade having a two-stage structure and separating from an extruded product.

[0002]

2. Description of the Related Art In a conventional discarding device for an extrusion press, a shearing device for cutting a discard 34 is provided downward on a frame 8 provided on the container 7 side above an end platen 1 holding a die 2. The shear blade is attached to the lower end of the piston rod of the shear cylinder via the shear slide 13, and the shear blade has a single-stage structure.

[0003]

Conventionally, in an extrusion press, the cutting blade surface of the shear blade is not flush with the die end surface due to the temperature change of the die 2 and the gap between the die assembly and the die slide. If the position of the end face fluctuates within a range of about 0.5 to 1 mm and the distance between the shear blade and the die end face of the one-stage configuration widens during the discard cutting, the cut end of the discard becomes worse. For example,
If there is a porthole on the container 7 side of the dice 2,
The aluminum alloy in the porthole is scraped off when cut by the shear. Then, at the time of the next extrusion, the air in the squeezed space is contained in the extruded product, and bubbles or blisters are generated in the extruded product.

Further, the cut end surface is not a uniform surface but an uneven surface. The cause depends on the tip shape of the shear blade having the one-step structure. For example, when the shear blade 30 having a one-stage structure has an obtuse angle, the die 2 is attached to the shear slide 13 during shearing.
The moment of trying to separate from acts on the aluminum alloy that remains on the lower side of the cutting of the discard 34 and becomes thicker.

Further, the effect of the difference in shear blade shape will be described in detail. As shown in FIG. 11 and FIG.
At the time when the shear blade 30 starts the cutting of the discard 34 (FIG. 11A) using a shear blade having a one-step configuration in which the shear blade edge tip thickness t is 20 ° and 0.5 to 1 mm,
The distance between the end face on the die 2 side and the shear blade 30 (hereinafter referred to as the shear blade entry position) is, for example, 0.5 to 1 mm, but at the end of cutting (FIG. 11 (b)), the shear blade 30 dies 2
Discard remaining part 38 to enter so that it approaches the face
Becomes thinner as shown in FIG.

While the discarding is repeatedly cut by the shear blade as described above, the cutting surface shape of the discard becomes uneven due to the change of the entering position of the shear blade. Air is trapped between the abutment surfaces of the billet, which causes blisters in the extruded product.

Next, as shown in FIG. 12, the cutting edge angle α40 °,
The shear blade is a discard 34 using a shear blade 30 having a one-stage structure in which the tip thickness t of the shear blade is 0.5 to 1 mm.
When the cutting is started (Fig. 12 (a)), the shearing blade 30 has an entering position of, for example, 0.5 to 1 mm, but the cutting blade surface of the shearing blade 30 is gradually dissipated as the cutting progresses from the start of cutting. Since the card 34 is attached, a moment to move away from the die 2 acts on the shear slide 13 and the discard residual portion 38 is left at the cutting end (FIG. 12B).
Becomes thicker as shown in FIG.

Further, conventionally, there is, for example, 0.5 to 1 mm of cutting residue on the die surface after the discard cutting, and this thickness is not uniform depending on the shape of the extruded shape member. For example, it is not uniform due to the difference between the solid shape member and the hollow shape member and the size of the hollow shape chamber. In this case, changing the shear blade according to the shape of the extruded shape is one method, but in reality, it takes time, and the delicate selection of the shear blade is difficult, and many shear blades are used. It is also impractical to prepare.

[0009]

According to the first aspect of the present invention, in the first aspect of the present invention, a disc mounted downward is attached to a frame provided on the container side of an end platen holding a die. Using a chilching shearing device with a die pressing mechanism for card cutting, the container is moved away from the die after extrusion, and the discard, which is the extruded residue of the billet, is moved to the front side of the die using a shear blade with a two-stage structure. I decided to disconnect. Further, in the second invention, after the extrusion molding, the container is separated from the die and retracted, and then the discard which is the extrusion residual part of the billet is cut at the front side of the die to be separated from the extrusion molded product. In the device, a tilting shearing device with a die pressing mechanism for discard cutting attached downward to a frame provided on the container side of the end platen holding the die is rotatably attached in the extrusion and anti-extrusion directions, A two-stage shear blade is attached to the lower end of the piston rod of the shear cylinder, and a guide device capable of pressing the die toward the end platen is attached next to the two-stage shear blade, and the frame and die attached to the end platen. A clearer between the shear blade of the two-stage structure and the front surface of the die between the tilting shear device with the pressing mechanism. The pressing device is provided which can adjust the scan.

[0010]

[Operation] After the extrusion work is completed, the container is retracted from the die to expose the discard part to the air, and then the tilting shear device with a die pressing mechanism for cutting discard is operated to remove the discard with the shear blade. The cutting is performed, but at that time, the guide device and the shear blade are lowered while the pressing device is operating.

At this time, due to the action of the guide device, the die is pressed in the extruding direction, and the shear blade is also pressed to the front side of the die, so that the cutting surface between the front surface of the die and the shear blade is cut. Since the position of is always at a preset position, the clearance between the front surface of the die and the shear blade is also kept at a preset size, and good cutting is performed. As a result, a good extruded product free of air entrainment and free of blisters can be obtained reliably and easily. Further, according to the present invention, it is possible to cut cleanly, leaving one skin of 0 to 0.3 mm.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. 1 is a front view showing a partial sectional view, and FIG.
Is a longitudinal sectional view showing a state immediately after cutting the discard, FIG. 3 is a partially enlarged transverse sectional view of FIG. 2, FIG. 4 is a rear view of the shear and guide device portion of the device shown in FIG. 5 is a front view of the shear blade, FIG. 5 (2) is a side view of the shear blade, and FIG. 6 is a partially cut sectional view of the chilching shear device. 7 is a cross-sectional view in which a sagging phenomenon occurred in the entrance hole at the time of cutting the discard, and FIG. 8 shows a cutting state when the discard was cut using a tilting shear device with a die pressing mechanism using a front blade edge angle of 20 °. FIG. 9 is an explanatory view showing a tilting shearing device with a die pressing mechanism and a front blade angle of the shearing blade of 40 °.
FIG. 10 is an explanatory view showing a cutting device when a discard is cut by using FIG. 10, and FIG. 10 is an explanatory view showing a cutting state when a shear blade having a two-stage structure having an appropriate structure is used for a tilting shear device with a die pressing mechanism. is there.

FIG. 1 shows an embodiment of the present invention, 1 is an end platen, 2 is a die, 3 is a die slide, and 4 and 5 are guides for guiding the movement of the die slide 3 in a horizontal direction perpendicular to the paper surface. A member, 6 is a block in the end platen 1 which receives a pressing force from the die 2. A hole through which a product extruded from the die 2 passes is provided at the center of the block 6 and the end platen 1. The die 2 is composed of several parts as shown in the figure. Reference numeral 7 is a container including a container tube 7a, a container body 7b, a container holder 7c and the like.

A frame 8 is attached to the container 7 side above the end platen holding the die 2 on the front side,
A tilting shearing device 10 with a die pressing mechanism for cutting discard is attached to a part of the frame 8 by a shaft 9.
It was attached so as to be rotatable in the extrusion and anti-extrusion directions. In the tilting shear device 10 with a die pressing mechanism, 11 is a shear cylinder, 12 is a piston rod, and a shear slide 13 is attached to the lower end of the piston rod 12.

A shear blade 14 is attached to the center of the inside of the shear slide 13 facing downward, and guide rollers (guide devices) are provided on both sides of the shear blade 14 of the shear slide 13 as shown in FIGS. Several 15 were arranged vertically on the die slide 3 side, and each was attached rotatably. 15
Reference numeral a is a bearing integrally provided on the die slide 3 side of the shear slide 13, and reference numeral 15b is a shaft that rotatably supports a guide roller (guide device) 15. The horizontal distance between the surface of the shear blade 14 on the die 2 side and the surface of the guide roller (guide device) 15 on the die slide 3 side is maintained at a predetermined constant distance. The lower end of the guide roller (guide device) 15 is positioned below the lower end of the shear blade 14 by a dimension of, for example, the radius or diameter of the die 2.

On a part of the upper side of the frame 8, a tilting shear device 10 with a die pressing mechanism is swung around a shaft 9, or a clearance between the shear blade 14 and the front surface of the die 2 is adjusted. The tilting cylinder pressing device 16 which is also a pressing device is attached, and the tip end portion of the piston rod 17 of the tilting cylinder pressing device 16 is attached to a part of the shear cylinder 11. The mounting positions of the cylinder pressing device 16 for tilting and the piston rod 17 are set considerably above the position of the shaft 9. In addition, an electromagnetic relief valve (not shown) is provided in the hydraulic circuit for the cylinder pressing device 16 for tilting, and the pressure is appropriately controlled so that the clearance between the die surface and the shear surface is, for example, 0 to 0.3 mm. like,
It can be adjusted and set in advance to a fairly small and appropriate value.

As shown in FIG. 3, a diameter of the die 2 on the side opposite to the extrusion direction is made slightly smaller than that on the side of the extrusion direction to form a step portion, and around this step portion, the inside of the die slide 3 on the side opposite the extrusion direction is formed. A hose shoe 18 that can hold the die 2 at the stepped portion is provided on the. A disc spring 19 is provided between the back surface of the horseshoe 18 and the bottom of the groove 3a for attaching the horseshoe of the die slide 3.
The horse shoe 18 was attached to the die slide 3 with a bolt 20.

Therefore, the horseshoe 18 is slightly pushed to the right side in FIG. 3 by the action of the disc spring 19 to a position where it is normally stopped by the head of the bolt 20, and the inner circumferential protrusion of the horseshoe 18 is a stepped portion of the die 2. It is only slightly away from the bottom of the groove 3a, and the backside of the horseshoe 18 is a little more than that from the bottom of the groove 3a. However, when pushed from the right side in FIG. Moving toward the bottom of the die, the inner circumference protrusion of the horse shoe 18 hits the step of the die 2 and pushes the die 2, and the die 2 is placed on the back side of the block 6
It is designed to stop at a predetermined position where it is pressed against. As described above, when the inner circumferential protrusion of the horse shoe 18 stops while contacting the step of the die 2, the end surface of the horse shoe 18 in the extrusion direction is slightly apart from the bottom of the groove 3a.

Reference numeral 21 is a guide plate fixed to the horse shoe 18, and is designed to move up and down with the guide roller (guide device) 15 being pressed against the surface of the guide plate 21. Therefore, the guide roller (guide device) 15 device can be referred to as a guide device capable of pressing the die 2 toward the end platen 1 via the hose shoe 18. The container 7 at the upper end of the guide plate 21
There is a tapered notch on the side so that when the guide roller (guide device) 15 descends, the guide plate 21 will start to hit the container 7 side smoothly and comfortably.

In the tilting shear device 10 with a die pressing mechanism shown in FIG. 1, 22 is a moving member provided integrally with the piston rod 12, 22a and 22b are detection rods provided above and below the moving member 22, respectively. Reference numerals 23 and 24 denote brackets integrally and directly attached to an upper portion and a lower portion of the shear cylinder 11, respectively, or indirectly via a member 25.
Position detection devices 26 and 27 such as limit switches and magnetic sensors are attached to a part of the upper side of the shear blade 13 and the shear rod 13 to which the shear blade 14 and the guide roller (guide device) 15 are attached, and the ascending limit of the piston rod 12. And the falling limit is detected, and the signal can be sent.

Next, regarding the shear blade 14 of the two-step construction of the present invention, the shear blade 14 has a cutting edge angle α, a two-step blade trailing angle β, a cutting edge tip thickness t, an inclined cutting edge surface length L and a vertical cutting edge surface. It shall be represented by the length S. From these five typical angles and dimensions, it was found that the angle between the cutting edge angle α and the two-step blade trailing angle β is an important factor for obtaining a good cutting surface.

In this embodiment, various experiments were conducted in order to obtain a good cut surface of the discard 34, and the following findings were obtained by combining the shear device and the shape of the shear blade.

Comparative Example 1 Cutting Conditions: When a shear blade having a one-stage structure with a tilting shear device is used (FIG. 6) Shear blade shape: Blade edge angle α: 40 ° As shown in FIG. Unpublished Japanese Patent Application No. Hei 5-327593, which is constructed based on the knowledge obtained in various experiments in a conventional shearing device, and the shearing blade 3 is used at and after cutting the discard 34.
The cylinder 0 can be tilted. This tilting shearing device is an improvement of the conventional shearing device in order to obtain a good cut surface of the discard 34. This tilting shear device has a single-stage shear blade 3
When 0 is attached and pressure oil is introduced into the cylinder 40 and the shear blade 30 is pressed against the side surface of the die 2 to determine the entry position of the shear blade 30, when the cutting is started, the shear blade 30 has no escape place between the discard 34 and the die 2. Because it enters in the state,
There is a problem that the center portion of the blade edge where the shear blade 30 and the die 2 surface are in contact with each other is rapidly worn and the shear blade 30 has a short life.

In addition, as shown in FIG. 7, a droop 42 is generated in the entrance hole 32, the charged billet abuts at the time of the next extrusion, and air is trapped in the gap generated by the droop 42 during the subsequent upset operation. It was found to cause blister formation in extruded products.

Next, by improving the above-mentioned tilting shear device, a tilting shear device 10 with a pressing mechanism as shown in FIG. 1 was developed so that the discard 34 can be cut into a desired thickness of one skin. did.

First, the operation of the tilting shear device 10 with a die pressing mechanism according to the embodiment of the present invention will be described.

First, when the extrusion operation is completed, as shown in FIG. 1, the container 7 and the extrusion stem (not shown) are retracted to separate the container 7 from the die 2. Then,
The discard 34, which is the extruded residue of the billet, not shown, appears in the air. In this state, the shear blade 14 having a two-stage structure is at the upper limit. Next, the piston rod of the cylinder pressing device 16 for tilting is slightly advanced to keep the tilting shear device 10 with a die pressing mechanism in a vertical state. The state at this time is shown in FIG.

Next, the shear cylinder 11 is operated and the shear slide 13 is lowered. Then, first, the guide roller (guide device) 15 contacts the surface of the guide plate 21, and continues to descend in that state. When the guide roller (guide device) 15 contacts the guide plate 21, the hose shoe 18 overcomes the force of the disc spring 19 and is slightly pushed in the pushing direction, and accordingly, the step portion of the die 2 is pushed by the hose shoe 18. , The die 2 is pressed against the block 6 on the end platen 1 side, and the front surface of the die 2 is in a desired fixed position. This is performed before cutting with the shear blade 14.

While keeping this state, the shear blade 14 descends together with the guide roller (guide device) 15, and eventually the discard 34 is cut by the shear blade 14. At this time, the horizontal distance between the end platen 1 side surface of the guide roller (guide device) 15 and the end platen 1 side cut surface of the two-stage shear blade 14 is adjusted to an appropriate constant distance in advance. . Therefore, the entry position between the end surface of the die 2 and the surface of the shear blade 14 is, for example, 0 to 0.3 m.
It is maintained at a constant clearance like m.

Further, by adjusting the hydraulic pressure of the tilting cylinder pressing device 16, the pressing force of the guide roller (guide device) 15 and the shear blade 14 toward the end platen 1 side is adjusted to a desired value. Therefore, the discard 34
Is always cut in a good condition with a smooth cut surface without any sagging, for example, leaving a uniform skin of 0 to 0.3 mm. As a result, the inclusion of air and the occurrence of blisters are eliminated.

In this apparatus, the position where the piston rod 17 of the cylinder pressing device 16 for tilting is attached to the shear cylinder 11 is considerably higher than the position of the shaft 9 which is the swing center axis, and the shear cylinder 11 Since the rotation shaft 9 is provided at a position where the tilting cylinder pressing device 16 does not receive the reaction force, the force pressing the end surface of the die 2 can be easily controlled by pressure control using an electromagnetic relief valve or the like. . As a result, the influence of the shape of the shear blade 14 on the cut surface of the die 2 side can be reduced.

A guide roller (guide device) 15 provided on the shear slide 13 presses the die 2 through the guide plate 21 and the hose shoe 18 at the shear time to change the temperature of the die 2 and to insert the die. It is possible to cut the discard while maintaining the clearance between the surface of the die 2 and the surface of the shear blade 14 having a two-stage structure at a value preset by adjustment without being affected by factors such as the clearance of No. Therefore, as described above, the thickness of the aluminum alloy or the like remaining in the die 2 can be made constant, so that a uniformly flat die-side cut surface can be obtained. For the above reasons, it is possible to eliminate the blister inclusion in the extruded product due to the defective cut surface on the die side.

When the discard has been cut, the state is as shown in FIG. When the discard is finished, the cylinder pressing device 16 for tilting is actuated to slightly rotate the tilting shear device 10 with a die pressing mechanism to separate the guide roller (guide device) 15 from the guide plate 21 and press the die. The guide roller (guide device) 15 and the shear blade 14 are raised in a state where the mechanism-equipped tilting shear device 10 is slightly inclined. Then, the tilting cylinder pressing device 16 is actuated at the upper limit to return the tilting shear device 10 with the die pressing mechanism to the vertical state,
Complete one cycle.

Comparative Example 2 Cutting conditions: 1 in a tilting shear device with a die pressing mechanism
When using a shear blade having a one-step configuration (FIG. 8) Shear blade shape; cutting edge angle α; 20 ° The shear blade 30 having a one-step configuration shown in FIG. 13 is attached to the chilling shear device with a die pressing mechanism shown in FIG. As shown in FIG. 8, the position of the shear blade 30 is, for example, 0 to 0.3 mm.
It is possible to cut with a single skin of 0 to 0.3 mm from the start of cutting (Fig. 8 (a)) to the end of cutting (Fig. 8 (b)) due to the adjustable height. (Fig. 8
(C)) 0.1 to 0.5 in the entrance hall 32.
A dent 44 having a size of mm was generated, but during the next extrusion, air was trapped in the dent 44 between the die 2 surface and the contact surface of the billet, and a blister was generated in the extruded product.

The phenomenon in which the depression 44 is generated is caused by the cutting edge angle 20.
When the shear blade 30 having a sharp 1-degree angle is used, when the shear blade 30 has insufficient rigidity and has a wedge action, it is pressed against the die where the cutting edge tends to move toward the die 2 surface side during cutting. By using the tilting shear device with a mechanism (FIG. 1), it is possible to prevent the cutting edge from moving toward the side of the die 2 side once, and the movement of the cutting edge is restrained and returned so as to be parallel to the side of the die 2. Conceivable.

Comparative Example 3 Cutting conditions: 1 for a tilting shear device with a die pressing mechanism
When a shear blade having a stepped structure is used (FIG. 9) Shear blade shape; cutting edge angle α; 40 ° Chilching shear device 10 with die pressing mechanism shown in FIG.
13 is attached to the shear blade 30 of the one-stage configuration shown in FIG.
As shown in FIG.
After adjusting to mm, it is possible to cut with one skin of 0 to 0.3 mm left from the start of cutting (Fig. 9 (a)) to the end of cutting (Fig. 9 (b)). (Fig. 9
In (c), a sag 42 was generated in the entrance hole 32, and during the next extrusion, air was trapped in the sag 42 between the die 2 surface and the contact surface of the billet, and a blister was generated in the extruded product.

The cause of the droop 42 is that when the discard 34 is attached to the cutting edge of the shear blade 30 during cutting,
The shear blade 30 must continue cutting while receiving a large resistance force, and for this reason, the drooping on the upper corner of the entrance hole 32 on the die 2 side (container 7 side) 4
2 is considered to occur.

In the embodiment of the present invention, the tilting shear device 10 with a die pressing mechanism and the shear blade 14 having a two-stage structure.
By combining the above, it is possible to perform the cut-off cutting of the discard 34 having a uniform and thin cut surface and good breakage.

Example 1 Cutting conditions: 2 in a tilting shear device with a die pressing mechanism
When using a shear blade having a stepped configuration (Fig. 10) Shear blade shape; Blade edge angle α; 20 ° 2 step blade trailing angle β; 5 ° Blade tip thickness t; Approximately 1 mm Inclined blade surface length L; 30 mm Vertical cutting Blade surface length S: approx. 10 mm Chitilting shearing device 1 with die pressing mechanism shown in FIG.
The shear blade 14 having the two-stage configuration is attached to the 0, and the insertion position of the shear blade 14 having the two-stage configuration is, for example, 0 to
When the discard 34 is advanced to be cut by the shear blade 14 having the trailing edge angle α20 ° and the two-step blade trailing angle β5 ° adjusted to 0.3 mm, the wedge edge of the shear blade 14 causes the blade edge to face the die 2 surface direction. However, when the discard 34 comes into contact with the rear cutting edge surface 46 of the shear blade 14, the moment to return the cutting edge to the container 7 side has a two-stage structure. It acts on the shear blade 14.

Due to the summing effect of the above, the cut on the die 2 side is cut substantially parallel to the die 2 surface without bending.

As a result, it was possible to cut with one piece of skin of 0 to 0.3 mm left, and a clean cut surface without sagging 42 and dents 44 was obtained.

As a result of various demonstration tests, the following results were obtained. Shear device; Chilching shear device with die pressing mechanism Shear blade; Blade angle α; 20 ± 5 ° 2-step blade trailing angle β; 5-10 ° Blade tip thickness t; Approximately 1 mm Inclined cutting surface length L; 20-30 mm Vertical cutting face length S; about 10 mm

When the added value of the cutting edge angle α and the two-step cutting edge angle β is 20 ° or less, a phenomenon similar to that of Comparative Example 2 occurs, and conversely 3
Since a phenomenon similar to that of Comparative Example 3 occurred at 5 ° or more, it is desirable to select the shear blade 14 having the two-stage structure with the angle and size of the above values. In the present embodiment, the shape of the rear cutting edge surface 46 of the shear blade 14 having a two-stage structure is used as shown in FIG. 5, but the shape is not limited to this, and the rear cutting edge surface 4 is not limited to this.
The same good results were obtained even when a rounded one or another shape was used.

[0044]

As is apparent from the above description, in the first aspect of the present invention, the discard attached downward to the frame provided on the container side of the end platen holding the die. Using a chilling shearing device with a die pressing mechanism for cutting, after the extrusion molding, the container is moved away from the die and retracted, and then the discard, which is the extrusion remainder of the billet, is cut at the front side of the die using a two-stage shear blade. Further, in the second invention, after the extrusion molding, the container is separated from the die and retracted, and then the discard, which is the extrusion residual portion of the billet, is cut at the front side of the die and separated from the extrusion molded product. In the discarding cutting device of the above, a discer attached downward to the frame provided on the container side of the end platen holding the die. A chilling shearing device with a die pressing mechanism for cutting blades is rotatably mounted in the extrusion and anti-extrusion directions, and a two-stage shear blade is attached to the lower end of the piston rod of the shear cylinder. A guide device that can press the die to the end platen side is installed next to the end platen, and the clearance between the shear blade of the two-stage structure and the front face of the die is adjusted between the frame attached to the end platen and the chilching shear device with the die pressing mechanism. By providing a pressing device that can be used, the clearance between the surface of the die and the surface of the shear blade having the two-stage structure can be always maintained at a constant value, and the die can be appropriately placed on the end platen side. It can be pressed by force. In this state, since the discard can be cut with a shear blade having a two-stage structure, the cut is bent together with the tilting shear device with a die pressing mechanism,
0 to 0. No sagging in the entrance hall and no dents.
It is possible to easily cut in the state where one sheet of 3 mm is left, and it is possible to surely obtain a cut surface having a good smooth surface. Therefore, since extrusion molding can be performed without causing air entrainment or blister generation in the next extruded product, the yield is significantly improved.

[Brief description of drawings]

FIG. 1 is a front view showing a partial cross-sectional view showing an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing a state immediately after cutting a discard using the present invention.

3 is a partially enlarged cross-sectional view of FIG.

FIG. 4 is a rear view of the shear and the guide device portion of the apparatus shown in FIG. 1 viewed from the die slide side.

FIG. 5 is a shear blade having a two-stage structure, FIG. 5 (1) is a front view of the shear blade, and FIG. 5 (2) is a side view of the shear blade.

FIG. 6 is a partially cut sectional view of a tilting shear device.

FIG. 7 is a cross-sectional view showing a sagging phenomenon in an entrance hole when a discard is cut.

FIG. 8 is an explanatory view showing a cutting state when a discard is cut by using a tilting shear device with a die pressing mechanism with a front blade edge angle of 20 ° of a shear blade.

FIG. 9 is an explanatory diagram showing a cutting state when a discard is cut using a tilting shearing device with a die pressing mechanism using a front blade tip angle of 40 ° of a shearing blade.

FIG. 10 is an explanatory diagram showing a cutting state when a shearing blade having a two-stage structure having an appropriate structure is used for a tilting shearing device with a die pressing mechanism.

FIG. 11 is an explanatory diagram showing a cutting state when a shear blade having a one-step structure with a blade angle of 20 ° is used in a conventional shear device.

FIG. 12 is an explanatory diagram showing a cutting state when a conventional shear device having a one-stage shear device having a blade edge angle of 40 ° is used.

FIG. 13 is a side view of a shear blade having a one-stage configuration.

[Explanation of symbols]

 1 End Platen 2 Dies 3 Dieslides 6 Blocks 7 Containers 8 Frames 9 Shafts 10 Dies Pressing Mechanism Chilting Shear Device 11 Shear Cylinders 13 Shear Slides 14 Two-stage Shear Blades 15 Guide Rollers (Guide Devices) 16 Cylinder Press for Tilt Device 30 Shear blade with one-stage structure 32 Entrance hole 34 Discard 38 Discard remainder 40 Cylinder 42 Drool 44 Recess 46 46 Rear cutting edge surface

Claims (2)

[Claims] 1. A container is separated from the die after extrusion by using a tilting shear device with a die pressing mechanism for discard cutting, which is attached downward to a frame provided on the container side of the end platen holding the die. A method for discarding a discard of an extrusion press, characterized in that after discarding the billet, the discard, which is the extrusion remainder of the billet, is cut at the front side of the die using a shear blade having a two-stage structure. 2. A discard cutting device of an extrusion press, wherein after the extrusion molding, the container is separated from the die and retracted, and then the discard that is the extrusion residual portion of the billet is cut at the front side of the die and separated from the extrusion molded product. A tilting shearing device with a die pressing mechanism for discard cutting, which is attached downward to a frame provided on the container side of the end platen holding the die, is attached rotatably in the extrusion and anti-extrusion directions. A two-stage shear blade is attached to the lower end of the piston rod, and a guide device that can hold the die on the end platen side is attached next to the two-stage shear blade, with a frame attached to the end platen and a die pressing mechanism. Adjust the clearance between the two-stage shear blade and the front face of the die between the tilting shear devices. The discarding device of the extrusion press provided with the pressing device to obtain.