JPH0576927A - Attached dummy device for mandrel extruder - Google Patents

Abstract

PURPOSE:To provide an attached dummy device for a mandrel extruder which removes a work by an ejector and can clean the inner wall of a container effectively. CONSTITUTION:A backup ring 7 is connected with the tip of the hollow stem 1. A dummy ring 5 is set on the outside of this backup ring 7, a dummy disk 6 is fitted into the inside of this ring 5 and the backup ring 7 and the dummy disk 6 are connected. A clearance (a) is formed in advance between the dummy disk 6 and the backup ring 7 so that the dummy disk 6 is bent backward in an extruding time. The contact face through which this ring 6 and the dummy disk 7 come in contact with each other is formed to be conical faces corresponding to each other so that the diameter of the dummy ring 6 is expanded with this bend.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an attached dummy device for a mandrel extruder.

[0002]

2. Description of the Related Art In a mandrel extruder for carrying out hollow extrusion molding of aluminum or its alloy, between a billet (B) and a hollow stem (10) for pressurizing the billet (B),
Dummy block (2 with mandrel insertion hole in the center)
0) is interposed so that the tip of the stem (10) does not come into direct contact with the billet (B) to prevent the stem (10) from being affected by heat and deforming.

By the way, in such an extruder, when the type of billet or the billet length is changed, or when a pressure-bonding pattern is likely to occur in the hollow shape member, the residue remaining on the inner wall of the container is removed. There is.

Conventionally, the cleaning of the inner wall of the container as described above has been carried out by inserting a scraping device separately called an ejector into the container (30) and scraping off the deposits on the inner wall.

[0005]

However, not only is the work using the ejector a little dangerous, but the work is time-consuming and costly because it must be carried out in a process different from the extrusion process. There was a drawback that it was expensive.

The present invention has been made in order to solve the above drawbacks, and an object of the present invention is to eliminate the work by the ejector and to efficiently clean the inner wall of the container.

[0007]

[Means for Solving the Problems] The object is to have an outer diameter smaller than the inner diameter of the container (3) and to have an inner peripheral surface (5
b) the dummy ring (5) formed on the conical surface that inclines in the radial direction toward the front of the container (3), and the outer peripheral surface (6)
a) is formed into a conical surface that inclines toward the rear of the container (3) in a diameter reducing direction at an inclination angle corresponding to the inner peripheral surface (5b) of the dummy ring (5), and the inner peripheral surface (5b) A dummy disk (6c) having a mandrel insertion hole (6c) in the center, which is fitted in the billet contact front surface (6b) so as to project more forward than the billet contact front surface (5c) of the dummy ring (5). 6), a large diameter portion (7b) and a small diameter portion (7a), and the front end surface (7d) of the large diameter portion (7b) is in contact with the rear end surface (5f) of the dummy ring (5). Is located at
The extruder includes a front end surface (7e) of the small diameter portion (7a) and a backup ring (7) which is spaced from the rear end surface (6d) of the dummy disk (6) via a gap (a). The hollow stem (1) of (A) and the backup ring (7) have a cylindrical first connecting member (8) having a mandrel insertion hole (8a) at the center on the inner peripheral surface side thereof.
And the dummy disc (6) and the backup ring (7) are connected to each other by a cylindrical second connecting member (9) having a mandrel insertion hole (9a) in the center thereof on the inner peripheral surface side thereof. It is achieved by an attached dummy device for a mandrel extruder, which is characterized by being connected by.

[0008]

Operation: During extrusion, the dummy disk receives pressure toward the backup ring by the billet. Since a gap is formed between the dummy disk and the backup disk, the peripheral end portion of the dummy disk is flexibly deformed by receiving the pressure.

At this time, the inner peripheral surface of the dummy ring, which is formed on the conical surface inclined in the radial direction toward the front of the container, is directed toward the rear of the container at an inclination angle substantially the same as the inclination angle of the conical surface. Since it is fitted to the outer peripheral surface of the dummy disk, which is formed on the conical surface that inclines in the diameter reducing direction, the dummy ring expands in diameter as the dummy disk flexibly deforms, and the outer peripheral surface of the dummy ring It is almost in contact with the inner wall surface. When the stem is advanced in this state to perform extrusion, cleaning of the inner surface of the container is performed simultaneously with extrusion.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described based on illustrated embodiments.

In FIGS. 1 and 2, (1) is a hollow stem, (2) is a dummy device detachably attached to the tip of the stem (1), (3) is a container, and (4) is It is a mandrel.

The dummy device (2) has a dummy ring (5), a dummy disk (6) and a backup ring (7) for reinforcement thereof, and these are connected to each other. 2) is connected to the stem (1).

The front end (5a) of the dummy ring (5) has an outer diameter smaller than the inner diameter of the container (3), and the inner peripheral surface (5b) of the front end (5a) is a container. The conical surface is formed so as to incline in the radial direction toward the front of (3).

The outer peripheral surface (6a) of the dummy disk (6) is formed into a conical surface which is inclined radially inward toward the rear of the container (3) at an inclination angle corresponding to the conical surface. The outer peripheral surface (6a) is in contact with the inner peripheral surface (5b). In this combined state, the billet contact front surface (6b) of the dummy disk (6) is projected further forward than the billet contact front surface (5c) of the dummy ring (5). A mandrel insertion hole (6c) is formed in the center of the dummy disk (6).

A backup ring (7) is arranged behind the dummy disk (6) and the dummy ring (5). The backup ring (7) has a small diameter portion (7a) on the front side of the container (3) and a large diameter portion (7a) on the rear side thereof.
formed in b). The rear end portion (5d) of the dummy ring (5) is screwed onto the small diameter portion (7a) in an externally fitted state. That is, the threaded portion (7c) formed on the outer peripheral surface of the small diameter portion (7a) and the female threaded portion (5e) formed on the inner peripheral surface of the dummy ring (5) are screwed together to be connected. Has been done. In this connected state, the rear end surface (5f) of the dummy ring (5) and the front end surface (7d) of the large diameter portion of the backup ring (7) are in contact with each other, while the diameter of the back-up ring (7) is large. The front end face (7e) of the small portion (7a) and the rear end face (6d) of the dummy disk (6) are separated from each other with a predetermined gap (a). This clearance (a) is generated by the pressure (indicated by arrow P in FIG. 2) in the backup ring direction acting on the dummy disk (6) as a reaction force from the billet at the time of extrusion so that the peripheral end portion of the dummy disk (6) is illustrated. As shown in 2, the outer diameter of the dummy ring (5) is changed to the container (3) by flexing and deforming in the backup ring direction.
It is provided to enlarge the inner diameter substantially the same as the inner diameter.

The peripheral end face (5 g) of this dummy ring (5)
Means that the peripheral end face (5g) is formed so as to be substantially parallel to the inner wall surface (3a) of the container (3) when the diameter is expanded and to be in a state of being substantially tangential to the inner wall surface (3a). It is desirable to set it in a forward inclined shape in advance. Here, "substantially parallel"
Is the inner wall surface (3a) of the container (3) where the peripheral edge surface (5g) is
The present invention includes not only the case of being completely parallel with respect to, but also the case of being slightly inclined. Most preferably, they are completely parallel or slightly inclined forward. If the width of the peripheral end face (5g) is too short, the leakage resistance becomes small and the extruded material leaks from between the dummy ring (5) and the container (3) during extrusion. The frictional force between (5) and the inner surface of the container (3) becomes large and the extrusion pressure becomes excessive.
Therefore, the width is preferably set in the range of about 10 to 30 mm.

The backup ring (7) and the hollow stem (1) are connected on the inner peripheral surface side thereof by a cylindrical first connecting member (8) having a mandrel insertion hole (8a) at the center. There is. The connecting member (8) has a male screw portion (8b) formed on the outer peripheral surface thereof, and the male screw portion (8b) corresponds to the inner peripheral surface positions of the backup ring (7) and the hollow stem (1). It is screwed into the female screw portions (1a) (7f) formed on the.

The dummy device (2) is arranged with the rear end surface (5f) of the dummy ring (5) in contact with the front end surface (7d) of the large diameter portion (7b) of the backup ring (7). In addition, the backup ring (7) and the dummy disk (6) have a cylindrical second connecting member (9) having a mandrel insertion hole (9a) at the center on the inner peripheral surface side thereof.
Are connected by. Similar to the first connecting member (8), this connecting member (9) also has a male screw portion (9b) formed on its outer peripheral surface, and the male screw portion (9b) has the male screw portion (9b). Also, the backup screw (7) is screwed into female screw portions (7g) (6e) formed at positions corresponding to the inner peripheral surface of the backup ring (7).

In the extruder equipped with the above-mentioned dummy device (2), when the hollow stem (1) is pushed forward during extrusion of aluminum material or the like, the billet is evenly pressed through the backup ring (7) and the dummy disk (6). Extrusion pressure is applied. On the other hand, as a reaction of this extrusion pressure, the dummy disc (6) receives pressure from the billet. Dummy disk (6) and backup ring (7)
Since a gap (a) is provided between the dummy ring (6) and the dummy disk (6), the peripheral edge of the dummy disk (6) is bent and deformed in the backup ring direction due to the above-mentioned pressure. Becomes almost equal to the inner diameter of the container (3), and the peripheral end surface (5g) of the dummy ring (5) is substantially in contact with the inner wall surface (3a) of the container. When the hollow stem (1) is advanced in this state to perform the extrusion, the cleaning of the inner wall surface (3a) of the container is performed at the same time as the extrusion. This operation is performed every time extrusion is performed.

[0020]

As described above, according to the present invention, the dummy ring advances when the outer edge of the dummy ring is almost in contact with the inner surface of the container during the extrusion. The dummy ring extrudes the deposit on the inner surface of the container. At the same time, it can be surely scratched out. Since it is possible to perform the cleaning action on the inner surface of the container by the dummy ring like hot water, it is no longer necessary to separately use the ejector, and it is possible to eliminate the danger and trouble in the work.

Moreover, since the inner surface of the container can be cleaned simultaneously with the execution of the extrusion, the cleaning work efficiency can be further improved. Further, since the cleaning is performed every time the extrusion is performed, it is possible to perform the extrusion always in an ideal state where there is no deposit on the inner surface of the container.

Since the dummy ring is formed to have a diameter smaller than the inner diameter of the container before the extrusion operation, the insertion operation of the dummy ring into the container at the time of extrusion is not hindered.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a dummy device according to the present invention.

FIG. 2 is a cross-sectional view showing a state after deformation of a dummy block.

FIG. 3 is a cross-sectional view showing a conventional dummy device.

[Explanation of symbols]

 1 ... Hollow stem 2 ... Container 5 ... Dummy ring 5b ... Inner peripheral surface 5c ... Billet contact front surface 5f ... Rear end surface 6 ... Dummy disk 6a ... Outer peripheral surface 6b ... Billet contact front surface 6c ... Mandrel insertion hole 6d ... Rear end surface 7 ... Backup ring 7a ... small diameter part 7b ... large diameter part 7d ... front end face 7e ... front end face 8 ... first connecting member 8a ... mandrel insertion hole 9 ... second connecting member 9a ... mandrel insertion hole a ... gap A ... extruder

Claims (1)

[Claims] 1. A container (3) having an outer diameter smaller than the inner diameter of the container (3) and an inner peripheral surface (5b) formed into a conical surface which is inclined toward the front of the container (3) in the radial expansion direction. The dummy ring (5) and the outer peripheral surface (6a) are the inner peripheral surface (5b) of the dummy ring (5).
Is formed in a conical surface that inclines toward the rear of the container (3) at an inclination angle corresponding to, and is fitted into the inner peripheral surface (5b) so that the billet contact front surface (6b) is a dummy ring ( 5) A dummy disk (6) having a mandrel insertion hole (6c) in the center, which is made to project more forward than the billet contact front surface (5c), a large diameter portion (7b) and a small diameter portion (7a). ) And the front end face (7d) of the large diameter portion (7b) is the rear end face (5f) of the dummy ring (5).
Backup ring in which the front end face (7e) of the small diameter portion (7a) is placed in contact with the rear end face (6d) of the dummy disk (6) via a gap (a). (7), the hollow stem (1) of the extruder (A) and the backup ring (7) have a cylindrical first inner peripheral surface side with a mandrel insertion hole (8a) in the center. A cylindrical second member that is connected by a connecting member (8) and has a mandrel insertion hole (9a) in the center of the dummy disk (6) and the backup ring (7) on the inner peripheral surface side thereof. An attached dummy device for a mandrel extruder, which is connected by a connecting member (9).