JPH0459145A - Rolling mill for forming ring - Google Patents

Abstract

PURPOSE:To simplify the structure of a rolling mill so that both backup rolls can be interlocked easily by setting a pair of backup rolls at symmetrical positions to an imaginary line connecting each center of rotation of a forming roll and a mandrel. CONSTITUTION:When part in the peripheral direction of an annular work 16 is rolled down by the forming roll 8 and the mandrel 15, the rolled down part 30 is located on the imaginary line 14 connecting each center of rotation of the forming roll 8 and the mandrel 15. Therefore, the backup rolls 18, 18 are located symmetrically to the rolled down part 30. Consequently, the press- contacting forces of the backup rolls 18, 18 to the work 16 during rolling are desired to be nearly the same value and both backup rolls 18, 18 can be interlocked easily to each other.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a rolling mill for ring forming.

(Prior art) Conventionally, the above-mentioned rolling mill has a
There are some that are shown in the publication.

According to this, a forming roll and a mandrel are provided which sandwich and roll down a part of the ring-shaped work in the circumferential direction from the radial direction. By rotating these forming rolls and the mandrel in opposite directions, the cross-sectional area of the workpiece is gradually reduced, thereby making the diameter of the workpiece a desired size.

In the above case, if vibration or the like occurs in the workpiece during the rolling process, the accuracy of the roundness and the like of the molded product will decrease. Therefore,
A pair of backup rolls are provided for holding the workpiece in a predetermined posture, and each of these rolls is pressed against the outer peripheral surface of the workpiece being rolled at a predetermined pressure.

(Problems to be Solved by the Invention) By the way, in the conventional configuration described above, since the positions of the backup rolls viewed from the rolling part of the workpiece are asymmetrical,
It is necessary to set the pressure contact force against the workpiece for each of these backup rolls. For this reason, it is difficult to interlock the two backup rolls so that they each function using a single pressure source, which means that the configuration of this rolling mill may become complicated.

(Object of the Invention) This invention was made in view of the above-mentioned circumstances, and its purpose is to simplify the configuration of a rolling mill by easily interlocking both backup rolls. do.

(Structure of the Invention) A feature of the present invention for achieving the above object is that a pair of backup rolls are positioned symmetrically with respect to an imaginary line connecting the respective rotation centers of the forming roll and the mandrel.

(for production) The effects of the above configuration are as follows.

When a part of the ring-shaped workpiece 16 is rolled down in the circumferential direction by the forming roll 8 and the mandrel 15, the rolling part 30 is located at each rotation center point 8 of the forming roll 8 and the mandrel 15.
It will be located on the imaginary line 14 connecting points a and 15a.

Therefore, in this invention, the pair of backup rolls 18.18 are positioned symmetrically with respect to the imaginary line 14, and therefore, the backup rolls 18.18 are positioned symmetrically when viewed from the rolling part 30 of the work 16. I will do it. Therefore, since the pressure contact force of each backup roll 18.18 with respect to the workpiece 16 during rolling may be approximately the same value, both of these backup rolls 18.18
This makes it easy to link the two together.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

1 to 3, reference numeral 1 denotes a rolling mill for forming the ring 2 by a so-called ring rolling method, and for convenience of explanation, the following description will be made with the direction of the arrow Fr in the figures as the forward direction.

The rolling mill 1 has a movable table 3 that is slidable only in the front-back direction on a fixed table (not shown). This movable table 3
A drive port 4 extending back and forth is screwed to the rear of the drive port 4, and the drive port 4 is driven in forward and reverse rotation by a DC or AC servo motor 5.

A main shaft 7 extending in the left-right direction is supported on the movable table 3,
A forming roll 8 is attached to this main shaft 7. A forming roll drive motor 9 that drives the main shaft 7 rotates the forming roll 8. In front of the forming roll 8, a bracket 11 is supported on a bracket 10 mounted on the fixed base, and the roll 11 is rotationally driven by a roll drive motor 12.

The axes of the forming roll 8 and the bearing roll 11 both extend in the left-right direction and are parallel to each other, and a mandrel 15 is provided between them. In this case, the center of rotation 15a of the mandrel 15 is located on the imaginary line 14 connecting the center points 8a, 11a of the forming roll 8 and the roll 11. The outer circumferential surface of the mandrel 15 is friction-bonded with the outer circumferential surface of the receiver roll 11,
The receiver rotates in conjunction with the rotation of the roll 11.

A circumferential portion of a ring-shaped work 16, which is the material of the ring 2, is sandwiched between the forming roll 8 and the mandrel 15 and rolled down. In this case, circumferential grooves 8b and 15b are formed on the outer peripheral surfaces of the forming roll 8 and the mandrel I5, and the same circumferential groove 8b.

A workpiece 16 is fitted between 15b.

A pair of upper and lower backup rolls 18.18 are provided that press against the outer peripheral surface of the workpiece 16. These two backup rolls 18, 18 have the same shape and size, and are interlocked with each other by interlocking means 19. This interlocking means 19 has a pair of rotating arms 2020 rotatably supported on the main shaft 7. Both rotating arms 20 have the same shape and size, and the backup roll 18 is supported at each rotating end. A gear portion 21 is formed at the base of each rotating arm 20, and a pair of intermediate gears 22 meshing with each gear portion 21 are connected to the movable base 3.
is supported by. Further, an interlocking gear 23 that meshes with the rain intermediate gears 22 and 22 at the same time is also supported on the movable base 3.

When either one of the rotating arms 20 and 20 rotates, the other rotates in the opposite direction by the same dimension as the one arm through the gear portion 21, intermediate gear 22, and interlocking gear 23. This allows both backup roles 1
8.18 always maintains a symmetrical position with respect to the virtual line 14. In the situation shown, both backup rolls 18.18 are located at an equal distance i from the imaginary line 14 in a direction perpendicular to it.

A hydraulic cylinder 25 is provided as a single pressure source that rotates the lower part of the rotating arms 20, 20 forward via a link 24, thereby causing the backup roll 18 to be positioned on the outer peripheral surface of the workpiece 16. Pressure is applied. In this case, as described above, when one of the two rotating arms 20, 20 rotates, the other rotates in the opposite direction by the same dimension at the same time, so both backup rolls 18, 18
Both are pressed against the outer circumferential surface of the workpiece 16 with the same pressing force.

When rolling the workpiece 16, the forming roll 8
The roller holder rotates the rolls 11 as shown by the imaginary lines in FIG. 1, and also drives the servo motor 5 to rotate the forming rolls 8 together with the movable base 3 as shown by the arrow B in the same figure.
is advanced to lower the workpiece 16. Then, work 1
The cross-sectional area of 6 decreases, and its diameter increases.

In FIG. 2, in contact with the outer peripheral surface of the work 16,
A contact 27 is provided which moves in the direction of arrow C in the figure as the diameter of the work 16 increases.
A linear scale detector 28 for detecting the amount of movement of 7 is provided. The detection signal from this linear scale detector 28 is input to a control device 29, which controls the servo motor 5, forming roll drive motor 9, and roller drive motor 12.

In FIG. 4, the control device 29 controls the roll drive motor 12 so that the number of rotations of the roll 11 increases in stages as the outer diameter of the workpiece 16 increases. As a result, rolling can be carried out smoothly and the rolling rate can be increased. As a result, rolling of 50% or more is possible, for example.

By the above rolling, the outer diameter of the workpiece 16 reaches the target value,
That is, when the desired ring 2 has been formed by reaching the position indicated by the imaginary line in FIG. finish.

(Effects of the Invention) According to the present invention, since the pair of backup rolls are positioned symmetrically with respect to the virtual line connecting the respective rotation centers of the mandrel and the forming roll that pinches and rolls down the circumferential portion of the ring-shaped work, Both of the backup rolls are positioned symmetrically when viewed from the rolling part of the work. Therefore, since the pressure contact force of each backup roll against the work being rolled can be approximately the same value, firstly, both of these backup rolls are interlocked with each other so that they each function independently using a single pressure source. becomes easier.

As a result, there is an advantage that the configuration of the rolling mill can be simplified.

Secondly, it is easy to control both of the backup rolls, and as a result, a ring with high accuracy such as roundness can be obtained.

(Margin below)

[Brief explanation of drawings]

The figures show an embodiment of the present invention; FIG. 1 is a side view, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is II+-[ of FIG.
The one-line arrow view and FIG. 4 are graphs. l...rolling machine, 2...ring, 8...forming roll, 8a
・・Center point, 8b・・Peripheral groove, 11・・Bake is a roll, ll
a: Center point, 14: Virtual line, 15: Mandrel,
15a... Center point, 16... Workpiece, 18... Backup roll, 19... Interlocking means, 30... Rolling part.

Claims (1)

[Claims] 1. Providing forming rolls and a mandrel that sandwich and roll down a part of the circumferential direction of the ring-shaped workpiece from the radial direction, and
In a ring forming rolling mill equipped with a pair of back-up rolls that press against the outer peripheral surface of the workpiece, the pair of back-up rolls are positioned symmetrically with respect to an imaginary line connecting the center of rotation of the forming roll and the mandrel. Rolling machine for forming.