JP2943970B2 - Discard cutting method and apparatus for extrusion press - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, an extrusion press for a metal such as an aluminum alloy, in which after extruding, a container is separated from a die and retreated, and a discard, which is the remaining extruded billet, is placed in front of the die. The present invention relates to a discard cutting method and apparatus for cutting with a two-stage shear blade and separating the extruded product.

[0002]

2. Description of the Related Art In a conventional extruder discard cutting apparatus, a shearing device for cutting a discard 34 is provided on a frame 8 provided on a container 7 above an end platen 1 holding a die 2. And a single-stage shear blade is simply attached to the lower end of the piston rod of the shear cylinder via a shear slide 13.

[0003]

Conventionally, in an extrusion press, the cutting blade surface of the shear blade is not flush with the die end surface due to a change in the temperature of the die 2 and a gap between the die assembly and the die slide. If the position of the end surface fluctuates in the range of about 0.5 to 1 mm and the distance between the shear blade having a single-stage configuration and the end surface of the die is widened during discard cutting, the cut end of the discard will deteriorate. For example,
If there is a porthole on the container 7 side of the die 2,
The aluminum alloy in the porthole is cut off during cutting by the shear. Then, at the time of the next extrusion, the air in the space taken away is sealed in the extruded product, and bubbles, ie, blisters, are generated in the extruded product.

[0004] Further, the cut cut surface is not a uniform surface but has an uneven surface. The cause varies depending on the tip shape of the single-stage shear blade. For example, when the shear blade 30 having a single-stage configuration has an obtuse angle, the die 2
Moment acting to separate from the discard 34 acts, and the aluminum alloy remaining on the lower side of the cutting of the discard 34 becomes thick.

Further, the effect of the difference in the shear blade shape will be described in detail. As shown in FIGS.
When the shear blade 30 starts cutting the discard 34 (FIG. 11A) using a single-stage shear blade having a shear blade edge tip thickness t of 0.5 to 1 mm at 20 °,
The distance between the end surface on the side of the die 2 and the shear blade 30 (hereinafter referred to as the position where the shear blade enters) is, for example, 0.5 to 1 mm, but at the end of cutting (FIG. 11B), the shear blade 30 is
Remaining discard 38 to get closer to the surface
Becomes thin as shown in FIG.

[0006] As described above, while the cutting of the discard is repeatedly performed by the shearing blade, the cutting position of the discard becomes irregular due to the change of the entering position of the shearing blade. Air is confined between the contact surfaces of the billet, and blisters are generated in the extruded product.

[0007] Next, as shown in FIG.
Using the shear blade 30 having a single-stage configuration in which the tip thickness t of the shear blade is 0.5 to 1 mm, the shear blade is used as the discard 34.
When the cutting is started (FIG. 12 (a)), the shear blade 30 enters at an entry position of, for example, 0.5 to 1 mm. Since the card 34 adheres, a moment to move away from the die 2 acts on the shear slide 13 and at the cutting end (FIG. 12B), the discard remaining portion 38
Becomes thicker as shown in FIG.

[0008] Conventionally, there is a cutting residue of 0.5 to 1 mm on the die surface after cutting the discard, for example, and this thickness is not uniform due to the shape of the extruded material. For example, it is not uniform due to the difference between the solid profile and the hollow profile and the size of the hollow chamber. In this case, it is one method to change the shear blade according to the shape of the shape to be extruded. However, in practice, it takes much time, and it is difficult to delicately select the shear blade. It needs to be prepared and is not practical.

[0009]

According to the present invention, in order to solve the above-mentioned problems, according to the first invention, a disk mounted downward on a frame provided on a container side of an end platen holding a die. After using a card cutting device to retract the container from the die to the extruder,
Lower the guide device and shear blade with the pressing device operating.
And press the die in the extrusion direction by the guide device.
With the shear blade pressed against the front of the die
And the tip angle of the shear is 20 ± 5 °, and the additional angle of the two-step blade is 5-10.
The discard, which is the remaining part of the billet extruded, was cut at the front side of the die using a shear blade having a two-stage configuration having an angle of two degrees . Further, in the second invention, after extruding the container, the container is separated from the die and retracted, and then the discard, which is the remaining part of the billet, is cut at the front side of the die to separate it from the extruded product. In the apparatus, a discer attached downward to a frame provided on the container side of an end platen holding a die
Mounted rotatably de cutting apparatus for extrusion and anti extrusion direction, shear the lower end of the piston rod of the chassis Linda
A guide capable of attaching a two-stage shear blade having a blade tip angle of 20 ± 5 ° and a two-stage blade follower angle of 5 to 10 °, and pressing a die to the end platen side beside the two-stage shear blade. Mount the device on the frame above the end platen
A pressing device capable of adjusting the clearance between the shear blade and the die front face of the two-stage configuration provided.

[0010]

After the extruding operation is completed, the container is moved away from the die, and the discard portion is exposed to the air. After that, the tilting shear device with a die pressing mechanism for cutting the discard is actuated, and the discard is removed by the shear blade. At that time, the guide device and the shear blade are lowered while the pressing device is operated.

At this time, the die is pressed in the pushing direction by the action of the guide device, and the shear blade is also pressed to the front side of the die. Is always at a preset position, the clearance between the front surface of the die and the shear blade is also maintained at a preset size, and good cutting is performed. As a result, a good extruded product without air entrainment and without blisters can be obtained easily and reliably. 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 EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a front view partially shown in a sectional view, and FIG.
3 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 of the apparatus shown in FIG. FIG. 5 is a shear blade having a two-stage configuration, FIG. 5 (1) is a front view of the shear blade, FIG. 5 (2) is a side view of the shear blade, FIG. FIG. 7 is a cross-sectional view showing a dripping phenomenon in an entrance hole when cutting a discard, and FIG. 8 shows a cutting state when a discard is cut using a tip angle of 20 ° of a front edge of a shearing blade in a tilting shear device with a die pressing mechanism. FIG. 9 shows a tilting shear device with a die pressing mechanism in which the front edge angle of the shear blade is 40 °.
FIG. 10 is an explanatory view showing a cutting device when a discard is cut by using a cutting tool, and FIG. 10 is an explanatory view showing a cutting state when a two-stage shear blade having an appropriate configuration is used in a tilting shear device with a die pressing mechanism. is there.

FIG. 1 shows an embodiment of the present invention, wherein 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. The block 6 and the center of the end platen 1 are provided with holes through which products extruded from the die 2 pass. The die 2 is composed of several parts as shown. Reference numeral 7 denotes a container including a container tube 7a, a container body 7b, a container holder 7c, and the like.

A frame 8 is mounted on the container 7 above the end platen holding the die 2 on the front side.
A tilting shear device 10 with a die pressing mechanism for discard cutting is mounted on a part of the frame 8 by a shaft 9.
It was mounted so that it could rotate 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 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. 15 were arranged in the vertical direction on the die slide 3 side, and each was rotatably mounted. Fifteen
a is a bearing integrally provided on the die slide 3 side of the shear slide 13, and 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 lower than the lower end of the shear blade 14 by, for example, the radius or the 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 pivoted about the shaft 9, or a clearance between the shear blade 14 and the front surface of the die 2 is adjusted. The tip of the piston rod 17 of the tilting cylinder pressing device 16 was attached to a part of the shear cylinder 11. The mounting positions of the tilting cylinder pressing device 16 and the piston rod 17 were considerably higher than the position of the shaft 9. In the hydraulic circuit for the cylinder pressing device 16 for tilting, an electromagnetic relief valve (not shown) is provided, the pressure is appropriately controlled, and the clearance between the die surface and the shear surface is set to, for example, 0 to 0.3 mm. like,
It can be adjusted and set in advance so as to be a fairly small and appropriate value.

As shown in FIG. 3, the die 2 has a step in the direction opposite to the extrusion direction which is slightly smaller than the side in the direction of extrusion, to form a step around the step. Is provided with a hose shoe 18 capable of holding the die 2 at the step. A disc spring 19 is provided between the back surface of the hose shoe 18 and the bottom of the hose shoe mounting groove 3a of the die slide 3,
The hose shoe 18 was attached to the die slide 3 by bolts 20.

Therefore, the hose shoe 18 is slightly pushed rightward in FIG. 3 by the action of the disc spring 19 to a position where it can be normally stopped by the head of the bolt 20. 3 and the back of the hose shoe 18 is slightly more away from the bottom of the groove 3a, but when pushed from the right side in FIG. Moves toward the bottom, and the inner peripheral projection of the hose shoe 18 hits the step of the die 2 and pushes the die 2, and the die 2 is moved to the block 6 on the back side.
To stop at a predetermined position where it is pressed. In this manner, when the inner peripheral projection of the hose shoe 18 is stopped in a state where it contacts the step of the die 2, the end face of the hose shoe 18 in the pushing direction is slightly separated from the bottom of the groove 3a.

Reference numeral 21 denotes a guide plate fixed to the hose shoe 18, and is configured to move up and down while a guide roller (guide device) 15 is pressed against the surface of the guide plate 21. Therefore, the guide roller (guide device) 15 device can be said to be 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 starts to smoothly and smoothly hit the container 7 side.

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. Brackets 23 and 24 are integrally mounted directly or indirectly via members 25 on the upper and lower portions of the shear cylinder 11, respectively.
Position detecting devices 26 and 27, such as limit switches and magnetic sensors, are attached to upper portions of the upper and lower ends of the shear slide 13 and the piston rod 12 to which the shear blade 14 and the guide roller (guide device) 15 are mounted, respectively. And the lower limit is detected, and the signal can be sent.

Next, with respect to the shear blade 14 having a two-stage configuration according to the present invention, the shear blade 14 has a cutting edge angle α, a two-step blade follow-up angle β, a cutting edge tip thickness t, an inclined cutting surface length L, and a vertical cutting surface. It is represented by length S. From these five typical angles and dimensions, it has been found that the angle between the cutting edge angle α and the two-step additional angle β is an important factor for obtaining a good cut surface.

In the present embodiment, various experiments were conducted to obtain a good cut surface of the discard 34, and the following knowledge was obtained by combining the shear device and the shape of the shear blade.

COMPARATIVE EXAMPLE 1 Cutting conditions: In the case of using a single-stage shear blade with a tilting shear device (FIG. 6) Shear blade shape; cutting edge angle α: 40 ° As shown in FIG. An undisclosed Japanese Patent Application No. 5-327593, which is constructed based on knowledge obtained through various experiments in a conventional shearing apparatus, and is used for cutting the discard 34 and after the cutting.
0 is tiltable by a cylinder 40. This tilting shear device is obtained by improving the conventional shear device in order to obtain a good cut surface of the discard 34. A single-stage shear blade 3 is attached to this tilting shear device.
When the cutting oil is introduced, pressure oil is introduced into the cylinder 40, the shear blade 30 is pressed against the side surface of the die 2, and the cutting position is determined after the shear blade 30 is inserted, the shear blade 30 has no escape between the discard 34 and the die 2. To enter in a state,
There is a problem in that the center of the blade edge where the shear blade 30 and the two surfaces of the dies are in contact with each other is worn quickly and the life of the shear blade 30 is short.

In addition, as shown in FIG. 7, a dripping 42 occurs in the entrance hole 32, the charged billet comes into contact at the next extrusion, and air is trapped in the gap formed by the dripping 42 during the subsequent upset operation. It has been found that it causes blistering of extruded products.

Next, the above-described tilting shear device is improved to develop a tilting shear device 10 having a pressing mechanism as shown in FIG. 1 so that the discard 34 can be cut to 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, and the container 7 is separated from the die 2. Then,
A discard 34, which is a billet extrusion residue (not shown), appears in the air. In this state, the two-stage shear blade 14 and the like are at the ascending limit. Next, the piston rod of the tilting cylinder pressing device 16 is slightly advanced to maintain the tilting shear device 10 with the die pressing mechanism in a vertical state. FIG. 1 shows the state at this time.

Next, the shear cylinder 11 is operated to lower the shear slide 13. Then, first, the guide roller (guide device) 15 hits the surface of the guide plate 21 and continues to descend in that state. When the guide roller (guide device) 15 comes into contact with the guide plate 21, the hose shoe 18 overcomes the force of the disc spring 19 and is slightly pushed in the pushing direction, so that the hose shoe 18 pushes the step of the die 2. 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 by the shear blade 14.

While maintaining this state, the shear blade 14 descends together with the guide roller (guide device) 15, and the discard 34 is cut by the shear blade 14. At this time, the horizontal distance between the surface of the guide roller (guide device) 15 on the end platen 1 side and the cut surface of the two-stage shear blade 14 on the end platen 1 side 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 kept at a constant clearance, as shown by 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 against the end platen 1 is adjusted to a desired value. Therefore, the discard 34
Is always cut straight and in a good condition on a smooth cut surface without dripping, for example, leaving one constant skin of, for example, 0 to 0.3 mm. As a result, entrainment of air and generation of blisters are also eliminated.

In this device, the position where the piston rod 17 of the tilting cylinder pressing device 16 is attached to the shear cylinder 11 is considerably higher than the position of the shaft 9 which is the swing center axis. Since the rotation shaft 9 is provided at a position where the reaction force is not received by the tilting cylinder pressing device 16, the force pressing the end face 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 on the die 2 side can be reduced.

The die 2 is pressed by a guide roller (guide device) 15 provided on the shear slide 13 through the guide plate 21 and the hose shoe 18 at the time of shearing, thereby changing the temperature of the die 2 and inserting the die receiver. The discard can be cut while maintaining the clearance between the surface of the die 2 and the surface of the two-stage shear blade 14 at a value set in advance without being affected by factors such as the clearance of the die. Therefore, as described above, the thickness of the aluminum alloy or the like remaining on the die 2 can be made constant, so that a uniform flat die-side cut surface can be obtained. And for the above-mentioned reason, it is possible to prevent the blister from being wound around the extruded product due to the defective cut surface on the die side.

FIG. 2 shows the state after the cutting of the discard is completed. When the cutting of the discard is completed, the tilting cylinder pressing device 16 is operated to slightly rotate the tilting shear device 10 with the die pressing mechanism, and the guide roller (guide device) 15 is separated from the guide plate 21 to press the die. The guide roller (guide device) 15 and the shear blade 14 are raised while the tilting shear device with mechanism 10 is slightly inclined. Then, the tilting cylinder pressing device 16 is actuated at the ascending limit to return the tilting shear device 10 with the die pressing mechanism to the vertical state,
End one cycle.

Comparative Example 2 Cutting conditions: 1 in a tilting shear device with a die pressing mechanism
When a shear blade with a step configuration is used (FIG. 8) Shear blade shape; blade angle α; 20 ° A shear blade 30 with a single stage configuration shown in FIG. 13 is attached to the tilting shear device with a die pressing mechanism shown in FIG. As shown in FIG. 8, the entry position of the shear blade 30 is, for example, 0 to 0.3 mm.
Can be cut from the start of cutting (FIG. 8 (a)) to the end of cutting (FIG. 8 (b)), leaving one skin of 0 to 0.3 mm. (FIG. 8
In (c)), the entrance hall 32 has 0.1 to 0.5.
However, at the time of the next extrusion, air was confined in the depression 44 between the die 2 and the contact surface of the billet, and blisters were generated in the extruded product.

The phenomenon in which the dents 44 occur is that the cutting edge angle 20
When the shear blade 30 having a single-stage configuration with an acute angle of ° is used, the dies are pressed against a place where the blade edge tends to advance in the discard 34 toward the dice 2 surface side during cutting due to insufficient rigidity and wedge action of the shear blade 30. By using the tilting shear device with a mechanism (FIG. 1), the tendency of the blade edge to once proceed to the side of the die 2 side is prevented, the movement of the blade edge is restrained, and the blade edge is returned to be parallel to the die 2 side. Conceivable.

COMPARATIVE EXAMPLE 3 Cutting conditions: 1 in a tilting shear device with a die pressing mechanism
When using a shear blade having a stepped configuration (FIG. 9) Shear blade shape; cutting edge angle α; 40 ° Tilting shear device 10 with a die pressing mechanism shown in FIG.
9 is attached to a one-stage shear blade 30 shown in FIG.
As shown in FIG.
mm, after the start of cutting (FIG. 9 (a)) to the end of cutting (FIG. 9 (b)), it is possible to cut one skin of 0 to 0.3 mm, but the cut cross-sectional shape after cutting (FIG. 9
In (c)), a droop 42 was generated in the entrance hole 32. At the time of the next extrusion, air was trapped in the droop 42 between the surface of the die 2 and the contact surface of the billet, and blisters were generated in the extruded product.

The cause of the droop 42 is that if the discard 34 is attached to the cutting edge of the shear blade 30 during cutting,
The shearing blade 30 must continue cutting while receiving a large resistance force. For this purpose, the shear blade 30 is placed at the upper corner on the surface of the die 2 of the entrance hole 32 (container 7 side).
2 would occur.

In the embodiment of the present invention, a tilting shear device 10 having a die pressing mechanism and a shear blade 14 having a two-stage configuration are described.
By combining the above, it is possible to perform the push-cutting of the discard 34 with 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 a shear blade with a stepped configuration is used (Fig. 10) Shear blade shape; blade angle α; 20 ° Two-step blade follow angle β; 5 ° Blade tip thickness t: about 1 mm Inclined cutting surface length L; 30 mm Vertical cutting Blade surface length S: about 10 mm Chitilching shear device 1 with a die pressing mechanism shown in FIG.
0, a two-stage shear blade 14 is attached, and as shown in FIG.
After adjusting to 0.3 mm, the cutting of the discard 34 is advanced by the shearing blade 14 having a cutting edge angle α20 ° and a two-step cutting edge angle β5 °. To the die 2 side, but when the discard 34 comes into contact with the rear cutting surface 46 of the shear blade 14, the moment to return the blade edge to the container 7 side has a two-stage configuration. Acts on the shear blade 14.

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

As a result, it was possible to cut one skin of 0 to 0.3 mm, leaving a clean cut surface without any droop 42 or dent 44.

As a result of various verification tests, the following results were obtained. Shearing device; Tilting shearing device with die pressing mechanism Shear blade; Blade angle α: 20 ± 5 ° Two-stage blade follow-up angle β: 5-10 ° Blade tip thickness t: Approximately 1 mm Inclined cutting surface length L: 20-30 mm Vertical cutting edge length S: about 10mm

When the sum of the blade angle α and the two-step blade follow-up angle β is less than 20 °, a phenomenon similar to that of the comparative example 2 occurs.
If the angle is 5 ° or more, a phenomenon similar to that of Comparative Example 3 occurs. Therefore, it is preferable to select the shear blade 14 having the two-stage configuration having the above-described angle and dimension. In this embodiment, the shape of the rear cutting surface 46 of the shear blade 14 having a two-stage configuration is used as shown in FIG.
Similar good results were obtained by using a material having a rounded shape in No. 6 and other shapes.

[0044]

As is apparent from the above description, in the first invention according to the present invention, the discard mounted downward on the frame provided on the container side of the end platen holding the dice. Using a cutting device , the extruder retracts the container away from the die and then presses
Lower the guide device and shear blade while the device is operating.
And press the die in the extrusion direction by the guide device.
With the shear blade pressed against the die front side,
The tip angle of the shear is 20 ± 5 °, and the additional angle of the two-step blade is 5-10 °.
The discard, which is the remaining part of the billet, is cut at the front side of the die by using a shear blade having a two-stage configuration. Further, in the second invention, after extruding, the container is separated from the die and retreated. In a discard cutting device of an extrusion press that cuts a discard, which is the remaining part of the billet, at the front side of the die and separates the extruded product from the extruded product, a discarding device is attached to a frame provided on a container side of an end platen holding the die. discard mounted toward
The cutting device is mounted rotatably in the extrusion and anti-extrusion directions,
A shear blade at the lower end of the piston rod of the shear cylinder
A guide device capable of attaching a two-stage shear blade having a tip angle of 20 ± 5 ° and a two-stage blade follow-up angle of 5 to 10 °, and pressing a die toward the end platen beside the two-stage shear blade. And a pressing device that can adjust the clearance between the shear blade of the two-stage configuration and the front surface of the die on the frame above the end platen . The clearance between the shear blade surface and the shear blade can always be maintained at a constant value, and can be kept pressed against the die and the end platen with an appropriate force. In this state, the discard can be cut with a two-stage shear blade, so that the cutout bends, the entrance hole is drooped, and further, a single 0-0.3 mm skin without dents is combined with the discard cutting device. Can be easily cut while leaving the surface, and a cut surface having a good smooth surface can be obtained easily and reliably. Therefore,
Extrusion can be performed without causing air entrapment or blistering in the next extruded product, so that the yield is greatly improved.

[Brief description of the drawings]

FIG. 1 is a front view, partially in cross section, showing one embodiment of the present invention.

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

FIG. 3 is a partially enlarged cross-sectional view of FIG. 2;

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

5 (1) is a front view of a shear blade, and FIG. 5 (2) is a side view of the shear blade.

FIG. 6 is a partial cross-sectional view of the tilting shear device.

FIG. 7 is a cross-sectional view in which a dripping phenomenon has occurred in an entrance hole when cutting a discard;

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

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

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

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

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

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

[Explanation of symbols]

 Reference Signs List 1 end platen 2 die 3 die slide 6 block 7 container 8 frame 9 axis 10 tilting shear device with die pressing mechanism 11 shear cylinder 13 shear slide 14 two-stage shear blade 15 guide roller (guide device) 16 cylinder press for tilting Apparatus 30 One-stage shear blade 32 Entrance hole 34 Discard 38 Discard remaining 40 Cylinder 42 Whore 44 Depression 46 Rear cutting surface

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B21C 35/04

Claims (2)

(57) [Claims] 1. A de-mounted downward on the frame which is provided on the container side of the end platen holding the die
After the container is separated from the die and retracted by the extruder using the discard cutting device , the pressing device is actuated.
The guide device and the shear blade are lowered in the
Press the dies in the extrusion direction with the shear blade
Is pressed against the front of the die, and the tip angle of the shear is 2
Extrusion characterized in that the discard, which is the remaining part of the extruded billet, is cut at the front side of the die using a two-stage shear blade having a 0- ± 5 °, two-stage blade addition angle of 5-10 °. Press discard cutting method. 2. A discard cutting device of an extrusion press, wherein, after extruding, a container is separated from a die and retracted, and then a discard as a remaining portion of the billet is cut at a front side of the die and separated from an extruded product. A discard cutting device attached downward to a frame provided on the container side of the end platen holding the dice is attached rotatably in the extrusion and anti-extrusion directions, and the lower end of the shear rod is attached to the lower end of the piston rod of the shear cylinder . Edge angle is 20 ± 5
°, together with the attaching the shear blades of the two-stage configuration having a two-stage blade additionally corners 5 to 10 °, fitted with a guide device capable of pressing a die to the end platen side next to the shear blades of the two-stage configuration, the end platen top A discard cutting device of an extrusion press, comprising a pressing device capable of adjusting a clearance between the two-stage shear blade and the front surface of the die on the frame of (1) .