JPS5929330B2 - Continuous indirect extrusion method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dynamically stable frictional continuous indirect extrusion method and apparatus.

The conventional indirect extrusion method will be explained with reference to Figure 1.
The mechanism is such that the container 10 and the stem 11' are fixed, and the stem 11' having the die 12' at the front moves in the right direction of the arrow, so that the material 13' contained in the container 10' is transferred to the stem 11'. ′ is extruded in the opposite direction.

However, according to this indirect extrusion method, the container 10
There is a limit to the amount of extrusion due to the capacity of It has the disadvantage of being a target.

Regarding the disadvantage of (1), it is disadvantageous when extruding long materials, and in this case, it is possible to use a material with a large diameter or a long material, but in the former case, the extrusion ratio is large. Therefore, the extrusion pressure becomes high, and in the latter case, the stem must be made longer, which has a limit due to the relationship with buckling strength.

In response, new extrusion methods and equipment have recently been developed which make it possible to continuously extrude long materials, such as those found in Japanese Patent Application Laid-Open No. 50-133153.

The extrusion method and device according to JP-A-50-133153 are equipped with opposing restraining walls that grip both opposing sides of a feed material having a rectangular cross section and lubricate the non-grip surfaces of the feed material, if necessary, upper and lower sides. It can be said that it is composed of a pair of caterpillars arranged opposite to each other.

Then, feed material between these caterpillars,
The restraining wall holds the feed material at a pressure higher than its yield strength, and the feed material is moved forward and extruded with this strong gripping force.

In this case, lubricant is supplied to the non-grip surface of the supplied material to reduce power loss due to friction.

The purpose of the present invention is to improve the extrusion method and device disclosed in JP-A-50-133153, to further reduce power loss, and to prevent as much as possible the occurrence of paris, which is the biggest problem when adopting a caterpillar mechanism. The object of the present invention is to provide a continuous indirect extrusion method.

The gist of the present invention is to prepare a pair of so-called caterpillar-type movable blocks each having an endless belt wound around a guide wheel, and the pair of movable blocks cover the entire circumference of the feed material in mutually restrained cooperating sections. Forming a tightly gripped and advanced container, the feed material is fed into the container and a mechanical frictional force is generated by contact around the entire circumference of the feed material, and the mechanical friction force causes the feed material to move through the container. In the method of pushing the container forward and extruding it from a die at the back of the container, a counter pressure is applied in the direction of movement of the endless belt at least in the section forming the container, in order to prevent the generation of cracks from the connecting gap of the endless belt. A continuous indirect extrusion method is characterized in that extrusion is carried out while being acted on.

In the above, a caterpillar refers to a device such as a belt-shaped steel plate or the like attached around a wheel.

Next, an embodiment of the method and apparatus of the present invention will be described with reference to the accompanying drawings FIGS. 2 to 5. In the figures, 10 is a frame;
11 and 12 are respectively a pair of movable blocks, guide wheels 13, 14, and guide wheels 15.
Endless belts 17 and 18 made of steel plate are placed around belt 16, respectively.
It consists of a caterpillar with an attached.

19 is a drive gear mechanism 20 is a supply material, 21 is an extruded material, 2
2 is a plurality of straightening rolls, and 23 is a stem holder.

As shown in FIGS. 3 and 4, the movable blocks 11, 12 form a cylindrical container 24 between the upper and lower belts with mutually restrained cooperating sections, and have power transmission teeth 25 on the sides. have

In FIG. 3, 26 is a fixed stem having a die 27 at the front, and has a through hole 28 for transferring the extruded material 21 therein.

As shown in FIG. 5, the drive gear mechanism 19 includes a drive shaft 31 connected to a power source via a worm shaft 29 and a worm gear 30, and a drive shaft 31 that meshes with the gear 25 on the side of the container 24. Gear 32 and pedestal 1
It has two bearing parts 33 fixed at 0.

This drive gear mechanism 19 is also provided with a counter pressure gear mechanism 34 acting in the opposite direction to the drive gear 32, as seen in FIG. 2, so that the material 20 forms the container 24. This prevents cracks from occurring from the connection gap of the bell N7.18.

In the extrusion device having such a configuration, in the extrusion operation, first, as shown in FIG. 2, when the rod-shaped material 20 is continuously fed into the container 24, the material 20 in the container As seen in Figures and Figure 4,
Container 24 based on movable block 11° 120 rotations
is transferred toward the stem 16 due to contact friction with the inner surface,
When this friction increases to a level equivalent to the extrusion pressure of the material 20, the material 20 is extruded through the die 27.

At this time, the drive gear mechanism 19 moves between the movable blocks 11 and 12.
In particular, by providing stable power to the container 24, this contributes to increasing the contact friction equivalent to a sufficient extrusion pressure.

According to the continuous indirect extrusion method of the present invention, a pair of caterpillar-type movable blocks 11 and 12 are used to tightly grasp the entire circumference of the feed material and move it forward, so that the material is extruded using mechanical frictional force due to contact. Therefore, compared to conventional extrusion using mechanical friction force, it is possible to reduce power loss and eliminate the need for lubricant, and since no lubricant is used, the quality of the extruded material is also improved.

Further, according to the method of the present invention, since a reverse pressure is applied to the endless belt in the direction of its movement, it is possible to prevent the generation of cracks, which is the biggest problem in the case of a caterpillar type mechanism.

The occurrence of sparks is very troublesome as it impedes the driving of the endless belt, rendering it inoperable and causing the extrusion pressure to become unsteady.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a conventional example, FIGS. 2 to 5 are explanatory diagrams of an embodiment of the continuous indirect extrusion method and apparatus of the present invention, FIG. 2 is a front view of the apparatus according to the present invention, and FIG. 4 is an enlarged sectional view of a main part thereof, FIG. 4 is a sectional view taken along line AA' in FIG. 3, and FIG. 5 is a side view of FIG. 2. 10... Frame, 11.12... Movable block, 13
゜14.15.16...Guide wheel, 17.18
...Endless belt, 19...Drive gear mechanism, 20...
- Supply material, 21... Extruded material, 22... Straightening roll, 24... Container, 25... Power transmission gear, 26
...Stem, 27...Die, 31...Drive shaft, 3
2... Drive gear, 34... Reverse pressure gear mechanism.

Claims (1)

[Claims] 1. A pair of so-called caterpillar-type movable blocks 11 and 12 are prepared, each of which has endless belts 17 and 18 wound around guide wheels 13.14 and 15.16, respectively, and the pair of movable blocks 11 and 12 are mutually restrained. A container 24 is formed in which the entire circumference of the feed material 20 is tightly gripped and advanced in the cooperating section, and the feed material 20 is fed into the container 24 in which the entire circumference of the feed material is subjected to mechanical frictional force due to contact. In this method, the feed material is advanced through the container using this mechanical frictional force and extruded from the die at the back of the container. A continuous indirect extrusion method characterized in that extrusion is carried out while applying opposite pressure to the endless belts 17 and 18 in the direction of movement of the endless belts 17 and 18 in the area where the belts are formed.