JPH0466221A - Method for chucking work on stretcher - Google Patents

Abstract

PURPOSE:To reduce the pressing deformation of the work by specializing the distance between the clamping surfaces of the clamping part for chucking on the work-chuck of the stretcher. CONSTITUTION:On the case for chucking the work by approaching/ separating a pair of the clamping parts 27 for chucking relatively, the clamping parts 27 for chucking are approached relatively till the prescribed position so that the distance between this clamping surfaces is made shorter than the thickness of the work A, clamp the work and stop to move and chucks while keeping the position of clamping parts at this position. Therefore, the pressing deformation of the work A caused with clamping can be controlled in min. limit, so the yield can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to stretchers used to stretch a metal extruded material such as aluminum formed by an extruder in extrusion equipment to correct bending, etc. Regarding the chuck method.

Background Art and Problems For example, an extrusion facility for aluminum material has a configuration as shown in FIG.

That is, (1) is an extruder, and (2) is a rear table disposed on the exit side of the extruder (1).

The rear table (2) consists of an initial table (3) formed by a free roller on the side of the extruder (1) and a run-out table (4) formed by a driving roller following the initial table (3). A blur (5) is attached to the runout table (4). A cooling table (6), a stretcher table (7), and a saw table (8) are arranged in parallel in order from the runout table (4) side adjacent to the side of the runout table (4). ing. The cooling table (6) and the stretching table (7) are each provided by a belt conveyor (9) arranged in parallel, and the saw table (8) is provided by a driving roller.

A stretcher (lO) is arranged on the stretch table (7). (60) (Go) is a chuck device for the stretcher (10). Also,
A cutter (15) is arranged on the saw table (8).

In the extrusion equipment described above, the extruded material extruded from the extruder (1) is conveyed to the runout table (4) via the initial table (3) while being pulled by the puller (5). After cutting with a platen cutter (not shown), it is conveyed to the cooling table (6) by the operation of the belt conveyor (9), and then to the stretching table (6).
7). In this stretch table (7), both ends of the extruded material are attached to the front and rear chuck devices (60
) (60), and one chuck device (
60) and the other chuck device (60).
) is stretched by moving and displacing them in the separating direction.

It is then carried to the saw table (8) and cutter (15).
It is cut to a predetermined length.

By the way, the chuck at the end of the extruded material during the above-mentioned stretch correction is generally carried out by moving a pair of clamping pieces, which are placed opposite each other while holding the extruded material, relatively close to each other using a predetermined drive device. This is done by clamping the outer circumferential surface of the material.

Conventionally, in order to prevent the extruded material from coming off the chuck device during stretching, this chuck moves both chuck pieces as close as possible to crush the end of the workpiece, and even after that, the end of the extruded material This was done by actively applying pressure to the area.

However, in this chucking method, large crushing deformation occurs at the ends of the extruded material, so the end deformation spreads to the center of the extruded material, and the effect spreads over a wider area due to stretching, and as a result, This method has the disadvantage that the length of the extruded material that can be used as a product is reduced, resulting in a low yield.

Particularly when the extruded material is a large hollow material, the effect of crushing deformation at the end extends over a fairly wide range, resulting in a significant reduction in yield.

The background to this problem is the fact that the extruded material was chucked with a large re-entrant force to prevent the workpiece from coming off the chuck device during stretching, and as a result, the lower limit of the chuck force That is, no consideration has been given to the minimum chuck force required to chuck the extruded material to prevent the extruded material from coming off the chuck device during stretching.

However, in view of the current situation where this is causing a decrease in yield, it is necessary to clarify this point and revise the above-mentioned chuck method.

Therefore, when we investigated the correlation between stretching force and chucking force, we found that although there are some differences depending on the cross-sectional shape and size of the extruded material, and the material, it was found that the ends of the extruded material were crushed to the maximum. It was found that stretching could be performed without any problem without deforming and chucking.

Moreover, it is only necessary to find out what method should be used to chuck the extruded material in the minimum crushed state that does not interfere with stretching.

From this point of view, one method is to empirically find the lower limit of the chuck pressure that does not hinder stretching, and based on this empirical value, calculate the reaction force from the extruded material that acts on the clamping piece during the chuck. One example is a chuck pressure control method in which the reaction force is detected and controlled to be kept constant throughout the chuck.

However, this method is actually very difficult to implement.

In other words, when chucking a stretcher, it is common for the extruded material to be plastically deformed to the extent that it becomes the end of the extruded material, and during chuck and stretching, the reaction force of the extruded material is rapidly reduced over time due to the progression of the plastic deformation. Change. Therefore, it is necessary to control the operation of the clamping piece with excellent responsiveness so that it can quickly follow the change, but such control is actually extremely difficult.

On the other hand, a method of chucking the extruded material in a manner that does not crush the ends at all by using a special jig has been considered. According to this method, it is possible to improve the yield, but on the other hand, the extruded material A dedicated jig must be installed and removed each time, which creates a problem in that the processing efficiency of the extruded material in the stretching process decreases.

Against this background, the present invention provides an easy-to-implement workpiece chuck method that allows stretching to be performed without any trouble while reducing deformation of the workpiece by the chuck compared to the conventional method, thereby reducing processing efficiency in the stretching process. The purpose is to improve yield.

Means for Solving the Problems In order to achieve the above object, the present invention provides a work chuck having a pair of chuck clamping pieces disposed opposite to each other, and a chuck drive unit that relatively moves the clamping pieces toward and away from each other. A method for chucking a workpiece in a stretcher using a device, the chuck clamping piece being driven by the chuck drive unit to a predetermined position where the distance between the clamping surfaces is shorter than the thickness of the workpiece in the chuck direction. The gist of the present invention is a method for chucking a workpiece in a stretcher, which is characterized in that after the workpiece is moved relatively close to the workpiece, the movement is stopped and the holding piece is held at that position.

Furthermore, the stopping position of the clamping piece after the approach movement prevents the extruded material from coming off from the chuck device during stretching.
It is most preferable to set the position at such a position that the amount of crushing deformation at the end of the extruded material can be reduced re-entrantly. Particularly in the case of a hollow workpiece, the position should be determined so that the workpiece can be chucked in an incompletely collapsed state that is not completely crushed.

Operation The above method determines the chuck force necessary for stretching in relation to the distance between the facing surfaces of both chuck pieces,
This is to chuck the workpiece. Therefore, deformation of the work by the chuck can be kept to the minimum necessary limit.

EXAMPLE Below, an example in which the chucking method of the present invention is applied to an extruded material chucking method in a stretcher of extrusion equipment will be described.
The explanation will be based on the drawings.

FIG. 1 shows the stretch drive side of a stretcher to which the method of the invention is applied. In the figure, (7) is a stretch table, and (lO) is a stretcher.

The stretch table (7) is provided by a number of belt conveyors (9) in parallel as described above.

In the stretcher (10), (17) is a rail, which is arranged parallel to the length direction of the extruded material (A). A cart (18) is movably disposed on this rail (17), and a chuck device (13) is attached to the cart (1B).
) is attached.

In addition, (20) is a stretch drive device using a hydraulic cylinder, and its cylinder rod (2 (la)) is connected to the trolley (
18), and applies tensile force to the extruded material (A) chucked by the chuck device (13) through the cart (18).

The chuck device (13) has a mounting member (22) fixed to the cart (18), and the mounting has a U-shape in which the back side of the vertical side portion (23a) is fixed to the front end of the member (22). The mounting has a frame (23). , and this installation is done on both the upper and lower horizontal sides (23b) of the frame (23).
Cylinder (25) (25) is attached to (23b) as a chuck drive unit in an opposing arrangement, and the cylinder rod (25a) (25a) thereof is arranged to protrude into the frame (23). And these cylinder rods (25a) (25a)
A chuck clamping piece (27) (27) is attached to each tip of the chuck clamping piece (27) (27) by driving the cylinder (25) (25).
) are mounted so that they can be moved relatively toward each other and away from each other within the frame (23).

The chuck device (13) is equipped with a positioning device (31) (31) for positioning the chuck holding pieces (27) (27). This positioning device (31) consists of an operating rod (32) and a linear scale (33).
). To explain with the upper device (31),
The linear scale (33) is erected on the upper surface of the horizontal side (23b) of the U-shaped frame (23). On the other hand, the actuating rod (32) has its base end attached to the clamping piece (27), and its tip end along the linear scale (38), so that the operating rod (32) is attached to the horizontal side (23b) of the U-shaped frame (23). It is projected in an upper position. An indicator needle (32a) protrudes toward the scale on the side surface of the upper end of the operating rod (32).
) is provided. That is, the position of the holding piece (27) can be adjusted by adjusting the height position of the indicator hand (32).

The extruded material end fixed holding side of the stretcher (10) is stretchable in that the chuck device is disposed in a fixed holding state or is arranged in a position adjustable manner according to the length of the extruded material. Although it is different from the drive side, the configuration of the chuck device itself is the same as the chuck device (13) above.
It has the same configuration as .

In the stretcher (IO), the end of the extruded material (A) is chucked as follows.

When carrying out this method, the clamping pieces (27) (27)
It is necessary to determine in advance the distance to be moved from the separated standby position. This distance is calculated based on the height h of the extruded material and the distance H1 of the extruded material (A) from the top surface of the stretch table (7) during stretching. This is done by considering the thickness α1+a2. The crushing thickness α1+α2 is such that the extruded material (A) does not come off from the chuck device (13) during stretching, and the amount of crushing deformation at the end of the extruded material (A) is re-entrantly reduced. Thickness, which is determined mainly based on empirical rules.

First, the end of the extruded material (A) is placed between the clamping pieces (27). And both cylinders (25)
(25), and the clamping pieces (27) and (27) located at the separated standby position as shown in FIG. 1 are moved relatively toward each other by distances determined as described above. At that time, the display needle (3) along the linear scale (33)
The movement of the holding piece (27) is controlled based on the movement of the holding piece (2a).

As shown in FIG. 2, each clamping piece (27)
After (27) is moved by the above-determined distance, the operation of the cylinders (25) (25) is stopped to stop the movement of the clamping pieces (27) (27).

Then, the cylinders (25) (25) are blocked in terms of a hydraulic circuit to hold the clamping pieces (27) (27) at their stop positions. As a result, the end of the extruded material (A) is chucked in an appropriate state with minimal crushing deformation that does not interfere with stretching.

Thereafter, in this chucked state, the stretch drive device (20) is driven to stretch the extruded material (A). During this stretching, the extruded material (A) is chucked in the proper state as described above, so the chuck fit
There is no deviation from (13). After that, the chuck device! The clamping pieces (27) (27) of (13) are moved away to the standby position to release the chuck of the extruded material (A).

Incidentally, according to comparative experiments, the length of the waste material at the end of the extruded material stretched using the chuck method according to the present invention was considerably reduced compared to stretching using the conventional chuck method using extreme crushing. It was confirmed that

Note that the method of the present invention can be widely used as a chucking method for stretching various workpieces, and is not limited to use as a chucking method for extruded materials in stretchers of extrusion equipment as described above. Needless to say.

Effects of the Invention As described above, the chucking method of the present invention moves the chuck clamping pieces relatively close to a predetermined position where the distance between the clamping surfaces is shorter than the thickness of the workpiece in the chuck direction. After clamping, the movement is stopped and the clamping piece is held at that position to chuck the workpiece, so that crushing deformation of the workpiece by the chuck can be suppressed to the necessary minimum. Therefore, the influence of deformation caused by the chuck and subsequent stretching on the surrounding area is reduced, and the yield can be improved. Moreover, the workpiece can be properly chucked by simply controlling the chuck holding piece by moving it a predetermined distance and then holding the holding piece at that position, making it easy to realize industrialization. It can be easily achieved. Furthermore, since there is no need to attach and detach a dedicated jig as in the past, there is no reduction in processing efficiency in the stretching process.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the stretch drive side of the stretcher used in the method of the present invention, Fig. 2 is a side view showing the state in which the chuck device chucks the end of the extruded material, and Fig. 3 is the extrusion equipment. FIG. 2 is a plan view showing the overall configuration. (lO)...Stretcher (13)...Chuck device, (25)...Chuck drive unit, (27)...
... Chucking piece, (A) ... Extruded material. that's all

Claims (1)

[Scope of Claims] Workpieces can be held on a stretcher using a work chuck device that has a pair of chuck clamping pieces arranged opposite to each other and a chuck drive unit that relatively moves the clamping pieces toward and away from each other. The chuck method comprises: moving the chuck clamping pieces relatively close to each other by driving the chuck drive unit to a predetermined position where the distance between the clamping surfaces is shorter than the thickness of the workpiece in the chuck direction; A method for chucking a workpiece on a stretcher, which comprises stopping the movement of the workpiece after clamping the workpiece, and holding the clamping piece at that position.