JPS6327091B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for cleaning a mandrel in a double-acting extrusion press for extrusion molding a tubular material.

To extrude a cylindrical product using an extrusion press, a mandrel is used as a core metal in addition to a die, and a metal such as an aluminum alloy is extruded under great pressure from around this mandrel to form the product.

Therefore, a film of metal such as aluminum alloy is attached to the outer peripheral surface of the mandrel. If the mandrel with this metal film attached is used again for extrusion press work, the diameter of the mandrel will increase by the amount of the metal film attached, and the inner diameter of the product will change, resulting in dimensional variations in the product. arise.

Conventionally, the metal adhering to the mandrel has been scraped off manually, or a semicircular blade that can be approached and separated from the entrance of the container has been installed, and this blade has been pressed against the mandrel to move the mandrel. Methods such as scraping off the stuck metal have been used, but all of these methods have the drawbacks of being complicated, time-consuming, and inefficient.

The present invention has been made to eliminate the above-mentioned conventional drawbacks, and provides a mandrel cleaning method for an extrusion press configured to efficiently and reliably remove metal attached around the mandrel. The purpose is to provide equipment.

In the present invention, in order to achieve the above object, a rotatable abrasive belt is pressed against the outer peripheral surface of a mandrel of an extrusion press, and at least one or more abrasive belts are A method and apparatus for cleaning the outer surface of the mandrel by movably supporting the pulley and rotating and moving the mandrel back and forth while rotating the abrasive belt was adopted.

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

1 to 3 illustrate one embodiment of the present invention, and the illustrated example shows an example applied to an indirect extrusion press.

In FIG. 1, 1 is a main cylinder, and a main ram 2 is slidably attached to the main cylinder 1.

A main crosshead 3 and a piercer cylinder 4 are fixedly attached to the main ram 2. Two pullback cylinders 5 as shown by two-dot chain lines in FIG. 1 are installed in parallel between a portion of the front of the main crosshead 3 and the platen portion 1a of the main cylinder 1. Therefore, the main crosshead 3 moves forward under the action of the main ram 2 and moves backward under the action of the pullback cylinder 5. A cylindrical stem 6 is attached to the front central portion of the main crosshead 3.

A piercer ram 7 is slidably attached to the piercer cylinder 4, and a piercer crosshead 8 is fixedly attached to the piercer ram 7.

The piercer crosshead 8 is provided in a hole 3a provided horizontally in the main crosshead 3 so as to be freely slidable in the axial direction.

A ram 9 extending rearward within the hole 3a is attached to the front part of the main crosshead 3.
The ram 9 is slidably attached to a cylinder 10 provided on the Piaser crosshead 8. Therefore, the piercer crosshead 8 moves forward under the action of the piercer ram 7 and retreats under the action of the cylinder 10. A mandrel 11 is fixed to the front central portion of the piercer crosshead 8, and the tip of the mandrel 11 extends slidably forward through the inside of the stem 6. 11a is, for example, a mandrel rotating device using a worm transmission device.

A cylinder 13 is attached to the platen portion 1a of the main cylinder 1, and the cylinder 13 moves back and forth so that its position can be adjusted by the action of an adjustment nut 12. A diameter portion 14a is slidably provided in the cylinder 13, and the forward movement of the large diameter portion 14a is restricted by a stopper portion 13a at the front end of the cylinder 13. Therefore, the stopper portion 13 of the cylinder 13
The forward movement limit position of the mandrel 11 is regulated by the action of the large diameter portion 14a of the rod 14 and the mandrel 11 is prevented from moving forward due to friction when the stem 6 is advanced to extrude the product.

Container 1 facing main crosshead 3
A cylindrical billet 1 made of aluminum alloy or the like is placed inside the container 15.
6. A dummy block 17 is supplied, and the stem 6 is pressed through the dummy block 17. A mandrel 11 is positioned in the center hole of the billet 11.

One end of a die stem 18 is inserted into the container 15 from the opposite side of the stem 6, and a die 19 is provided at the end of the die stem 18 on the billet 11 side.

16a is a product extruded from between the die 19 and the mandrel 11.

The other end of the die stem 18 is fixed to a die slide 20, which is slidably attached to an end platen 22 by a cylinder 21.

The end platen 22 and the platen portion 1a of the main cylinder 1 are connected by four tie rods 23. A crosshead 3, a container 15, etc. are slidably attached.

Using the two upper tie rods 23, a cleaning device 24 for cleaning the mandrel, which is the main part of the present invention, is attached.

The cleaning device 24 is attached to the two upper tie rods 23 via a support frame 25, as shown in FIGS. 2 and 3. A frame 27 is attached to the left and right support frames 25, 25 via a support plate 26 in a vertical manner to the upper part of the center of the machine.

A cylinder 28 is fixed downward to the upper end of the frame 27, and the tip of the piston rod 29 of the cylinder 28 is attached to the side surface near the lower end of a slide plate 30, which is attached to the frame 27 so as to be movable up and down, through a pin 31. are connected.

A motor 32 is attached to one side of the lower end of the slide plate 30.
An output shaft 32a passes through the slide plate 30 and extends to the opposite side, and a drive pulley 33 is fixed to the tip of the output shaft 32a. 32b is a bearing.

A drive pulley 33 is provided at the lower end of the slide plate 30.
The driven pulleys 34, 34 are attached with .

That is, on the outer surface of the lower end of the slide plate 30,
A bracket 35 is attached parallel to the slide plate 30, and arms 37 are rotatably attached to both sides of the lower end of the bracket 35 via pins 36, and a shaft 38 is attached to the tips of these arms 37. The driven pulleys 34 are rotatably attached to each other via the respective driven pulleys 34.

The driving pulley 33 and the driven pulley 34
A polishing belt 39 is wound around the belt. The abrasive belt 39 is, for example, also called a sander and is made of something like sandpaper.

Therefore, by the motor 32, the drive pulley 33
When the abrasive belt 39 is rotated, the abrasive belt 39 is run counterclockwise, for example as shown by the arrow in FIG.

The inner end side of the arm 37 to which the driven pulley 34 is attached, the slide plate 30 and the bracket 35
A tension spring 40 is stretched between the arms 37 and 37, and applies rotational force to each arm 37 in the direction of applying tension to the abrasive belt 39.
It gives a pressing force to. Also, this tension spring 4
0, even if the outer diameter of the mandrel 11 changes slightly, the mandrel 11 can be cleaned without changing the stroke of the piston rod 29.

A long hole 38a into which a shaft 38 fits is formed at the tip of one arm 37.
It is connected to one end of 1. Therefore, by adjusting the adjuster bolt 41, the tension of the abrasive belt 39 can be adjusted, and the tension of the abrasive belt 39 can be adjusted.
The structure is such that the polishing belt 39 can be easily removed when replacing the polishing belt 9.

Next, the operation of the mandrel cleaning method and mandrel cleaning device of the present invention configured as described above will be explained.

First, place the die 19, billet 16, dummy block 17, stem 6, mandrel 11, etc.
The main ram 2 and the container 15 are placed in the container 15 in the state shown in the figure, and the extrusion operation is performed by moving the main ram 2 and the container 15 forward. At the end of the extrusion operation, the die 19, mandrel 11, and piercer crosshead 8 are in the position shown in Fig. 1, and the container 15, stem 6, dummy block 17, main crosshead 3, etc. are in the position advanced to the left. It is in.

When the product extrusion operation is completed, the pullback cylinder 5 is operated to retract the main crosshead 3. At this time, the extrusion work of the mandrel 11 is completed, and the portion to which metal such as an aluminum alloy film is attached to the peripheral surface is exposed from the stem 6.

Until this product extrusion operation is completed, the lower end abrasive belt 39 of the cleaning device 24 for mandrel cleaning is lifted upward as shown by the two-dot chain line in FIG. 2, so that it does not interfere with the press operation. fleeing to the position.

Then, as described above, with the mandrel 11 positioned below the polishing belt 39, the cylinder 28
Activate. Then, the rod 29 will be extended,
The polishing belt 39 descends and comes into contact with the circumferential surface of the mandrel 11, as shown by solid lines in FIGS. 2 and 3.

In this state, the motor 32 is rotated and the abrasive belt 39 is rotated counterclockwise, for example, as shown by the arrow in FIG.
When the polishing belt 9 is pressed against the mandrel 11, the frictional force of the polishing belt 39 against the mandrel 11 increases, and polishing can be performed reliably.

On the other hand, the mandrel 11 is rotated in the opposite direction to the polishing belt 39 as shown by the arrow in FIG.
etc., it is moved back and forth in the axial direction.

In this way, the mandrel 11 is rotated,
And, by moving back and forth, the mandrel 11
It is possible to reliably remove the metal film attached to the peripheral surface of the metal film.

As is clear from the above description, according to the present invention, a rotatable abrasive belt is pressed against the outer peripheral surface of a mandrel of an extrusion press, and the mandrel is rotated and moved forward and backward while the abrasive belt is rotated. Because it is configured to clean the outer peripheral surface of the
You can clean the mandrel.

Note that during the press operation, the abrasive belt escapes to a position where it does not interfere with the operation, so it does not interfere with any part of the press device.

[Brief explanation of the drawing]

The drawing shows one embodiment of the device of the invention,
Figure 1 is a longitudinal sectional view showing the structure of an extrusion press, Figure 2
FIG. 3 is a front view and a side view of the cleaning device. 1...Main cylinder, 2...Main ram, 3
...Main crosshead, 4...Piercer cylinder, 5...Pullback cylinder, 6...Stem,
7...Piasa Lum, 8...Piasa Crosshead,
9... Ram, 10... Cylinder, 11... Mandrel, 12... Adjustment nut, 13... Cylinder, 15
... Container, 16 ... Billet, 18 ... Die stem, 19 ... Die, 22 ... End platen, 23 ... Tie rod, 24 ... Cleaning device, 27 ... Frame, 28 ... Cylinder, 3
0...Slide plate, 32...Motor, 33...Drive pulley, 34...Driven pulley, 39...Abrasive belt.

Claims (1)

[Claims] 1. A rotatable abrasive belt is pressed against the outer peripheral surface of a mandrel attached to an extrusion press, and at least one or more pulleys are moved in response to fluctuations in the load of the pressing force applied to the abrasive belt. can be pivoted,
A method for cleaning a mandrel for an extrusion press, which comprises cleaning the outer surface of the mandrel by rotating and moving the mandrel back and forth while an abrasive belt is rotating. 2. In an extrusion press in which a mandrel is provided so as to be freely movable back and forth in the extrusion direction and rotatable, an abrasive belt provided rotatably in a direction intersecting the extrusion direction is moved in the extrusion direction so that it can be pressed against the outer surface of the mandrel. The shaft of at least one of the pulleys provided to be movable in intersecting directions and suspending the abrasive belt is pulled at one end so as to be variable in accordance with fluctuations in the load of the pressing force applied to the abrasive belt. A mandrel cleaning device for an extrusion press, which is equipped with a spring and is pivoted at the other end of an arm that is pivoted at the center.