JPH0314535B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method of supplying material to a hot forging machine, for example, after unwinding a coiled material, straightening and
The present invention relates to a method of supplying the material when it is heated and then supplied to a hot forging machine.

(Prior art) Conventionally, in a hot forging machine for manufacturing nuts, etc. from wire rods, a long straight bar is intermittently drawn and fed by a feed roll installed on the exit side of a heating furnace. It was common to cut the pieces into a predetermined amount and then forge the cut pieces. In this case, since the material is a straight bar, there is a limit to its length, and a considerable length of cut waste material is produced at the joint with the next straight bar, which is uneconomical. For this reason, devices have emerged in which the material is formed into a coil shape, unwound, straightened and heated, and then fed to a hot forging machine, as is done in a cold forging machine. (Japanese Patent Application Laid-open No. 58-38632).

However, although such a device is practical for relatively small-diameter materials, when the material becomes large-diameter, the straightening machine after material unwinding must be multistage, and the material The driving force of the feed roll, which is driven by forward and reverse reciprocating rotation to provide the feed force of
It requires a link mechanism and is not practical. Furthermore, it is difficult to directly utilize the hot forging machine at the rear stage of a conventional device for long straight bars and connect the present mechanical means to the front stage. This is because it is impossible to attach a mechanically transmitted shaft to the crankshaft. Furthermore, since the straightened material is retracted upward when the feed rolls are reversed, there is a risk of bending deformation. Furthermore, since the adjustment is controlled by a cam link and a lever mechanism, there is a limit to its accuracy.Therefore, a stopper is essential, and it is necessary to adjust the stopper and link when controlling the cutting length, and the responsiveness is low. It had the drawback of being bad.

Therefore, the present applicants proposed in Japanese Patent Application No. 60-38903 a material supply device which eliminates the above-mentioned drawbacks and can be sufficiently applied to materials with a considerably large diameter.

The material supply device in this patent application No. 60-38903 is a forging line consisting of a coil unwinding mechanism 1, a straightening mechanism 2, a feed roll 3, a heating device 4, and a hot forging machine 5. The apparatus is characterized in that it is provided with a control means for extracting the forging timing of the forging machine 5 as an electric signal and controlling a feed roll drive means mechanically independent from the hot forging machine 5 based on the signal, This is an excellent material supply device that can solve the drawbacks of the conventional method (see Figure 4).

(Problem to be solved by the invention) However, by using the above-mentioned material supply device proposed by the present applicant, a large diameter material, for example, about 50 mm in diameter, is supplied to a hot forging machine and a predetermined forging process is performed. Subsequent experiments revealed that the following problems would occur if the

In other words, in the case of large diameter materials, the time required to cut the material with a hot forging machine is relatively long (approximately
0.08 seconds), the material thermally expands during cutting (approximately 0.17
mm). Therefore, as shown in FIG. 5, a lateral load acts on the movable blade 6, causing damage to the blade.
Due to the large pushing force caused by thermal expansion, the cut surface becomes oblique, leaving uncut edges and burrs. This burr becomes a cause of rashes. Since the material is restrained on both sides of the heating device 4 by the feed roll 3 and the movable blade 6, the material gradually curves due to thermal expansion, which gradually accumulates and damages the heating device 4. Therefore, after operating for a certain period of time, it is necessary to temporarily stop the operation and remove the curvature. etc.

The present invention has been made in view of the above-mentioned problems, and even when it takes a relatively long time to cut materials such as large-diameter materials, good cutting can be performed and high-quality forged products can be obtained. The purpose is to provide a method for supplying materials that can be manufactured.

(Means for Solving the Problem) The present invention provides a method for heating a material fed by a feed roll to a required temperature and then supplying the material to a hot forging machine equipped with a cutting device. During cutting by the equipped cutting device and from immediately after cutting until the retraction of the movable blade is completed, the feed roll is reversed so that the trailing end surface of the material does not move in the material feeding direction due to thermal expansion and maintains the cutting start position. The gist of this is to control.

(Function) The method of the present invention operates the feed roll so that the trailing end surface of the material does not move in the material feeding direction due to thermal expansion and maintains the cutting start position during cutting and from immediately after cutting until the movable blade completes retraction. In order to perform reverse control,
There is no interference between the cutting material and the movable blade, and the movable blade can move smoothly during and after cutting. Furthermore, according to the method of the present invention, there is no curvature of the material due to thermal expansion between the movable blade and the feed roll, so continuous operation is possible.

(Example) The present invention will be described below based on FIGS. 1 to 3.

First, a forging cycle of a hot forging machine that supplies material according to the method of the present invention will be explained. (See Figure 3).

The horizontal axis in FIG. 3 shows the rotation angle of the crankshaft of the crank type forging press that constitutes the hot forging machine 5, and the vertical axis shows the slide of the forging press that advances and retreats by rotation of the crankshaft, the movable blade, and the material. It also shows the stroke of the clamper.

In other words, 0° on the horizontal axis is the forward limit of the movable mold attached to the slide of the forging press, and this movable mold gradually retreats from 0° to 180°.
Retraction limit is reached at 180°. The movable mold gradually moves forward from 180° to 360°, and reaches its advancement limit at 360°. This cycle is then repeated.
On the other hand, the material is intermittently fed by the feed roll 3, and material feeding starts when the angle is 30°.
Material feeding is completed at 110°. Immediately after this material feeding is completed, the clamper 7 is moved to clamp the material. Also, during this time, the movable blade 6 gradually retreats to 30°,
It reaches the retraction limit at 30° and maintains that state up to 120°. Then, it starts moving forward from 120° and finishes cutting the material at 180°. After that, it continues to move forward, and when it reaches its forward limit, it temporarily maintains that state and then starts moving backwards again.

The present invention is a method for supplying material 8 by feed roll 3 to hot forging machine 5 having the above-described forging cycle, and is carried out as follows.

For example, based on the material of the material 8 to be supplied, the heating temperature in the heating device 4, the time required for cutting, etc., the time period from when the movable blade 6 is completely retracted during cutting and immediately after cutting, and during that time when the material 8
The elongation due to thermal expansion is determined and input into the control device 9 in advance. This control device 9 is electrically connected to the crankshaft of the forging press, and a signal when the feeding of the material 8 is completed or a signal when the movable blade 6 starts retreating is extracted from the rotation angle of the crankshaft of the forging press, for example. It is configured so that the information is transmitted to the control device 9.

Then, the control device 9 issues a signal to the drive motor 10 of the feed roll 3 based on the signal from the crankshaft and the time and elongation values inputted in advance, and controls the feed roll 3 in reverse, thereby controlling the feed roll 3 during cutting and the elongation value. The trailing end surface of the material 8 is made to maintain the cutting start position from immediately after cutting until the movable blade 6 completes retraction.

Note that 11 in the figure is a fixed blade.

(Experiment results) Material S45C, outer diameter φ50mm was heated using a heating device.
It was heated to 1200°C and fed to a hot forging machine at a feed stroke of 100 mm and a feed frequency of 100 strokes/min. In this case, the time required to cut the material is
0.08 seconds, the time required from immediately after cutting to the completion of retraction of the movable blade was 0.37 seconds, and the elongation due to thermal expansion during this time was 0.9 mm, so the above-mentioned intermediate feed roll (outer diameter φ300 mm) was rotated in the reverse direction at 0.127 rpm. When controlled in this manner, a good continuous cut surface was obtained, and no curvature occurred in the material.

(Effects of the Invention) As explained above, the present invention maintains the cutting start position without moving the trailing end surface of the material in the material feeding direction due to thermal expansion during cutting and immediately after cutting until the retraction of the movable blade is completed. Since the feed rolls are controlled in the reverse direction so as to do so, there is no interference between the material to be cut and the movable blade during cutting and immediately after cutting until the movable blade completes retraction, allowing smooth cutting. Therefore, the movable blade will not be damaged, and the cut surface of the material will also be good, so that no scratches will occur on the product.
Further, according to the present invention, there is no curvature of the material between the feed roll and the movable blade, so continuous operation is possible, and manufacturing efficiency is improved, which is a great invention.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the method of the present invention, A is at the time of completion of feeding the material, B is at the time of cutting, Fig. 2 is an explanatory diagram of the control of the method of the present invention, Fig. 3 is a forging cycle diagram, and Fig. 4 is FIG. 5 is a front view of the material supplying apparatus using the method of the present invention, and is an explanatory view of cutting when supplying material by the conventional method. 3 is a feed roll, 4 is a heating device, 5 is a hot forging machine, 6 is a movable blade, 7 is a clamper, 8 is a material, and 9 is a control device.

Claims (1)

[Claims] 1. In a method of heating the material fed by a feed roll to a required temperature and then supplying the material to a hot forging machine equipped with a cutting device, during cutting by the cutting device equipped on the hot forging machine and immediately after cutting. A hot forging machine characterized in that the feed roll is controlled in reverse so that the trailing end surface of the material does not move in the material feeding direction due to thermal expansion and maintains the cutting start position until the movable blade completes retraction. material supply method.