US3693779A

US3693779A - Roll for displacement of bar-like products

Info

Publication number: US3693779A
Application number: US165242A
Authority: US
Inventors: Georges L P Tavernier; Robert L Dubois
Original assignee: USINOR SA
Current assignee: USINOR SA
Priority date: 1968-01-22
Filing date: 1971-07-22
Publication date: 1972-09-26
Anticipated expiration: 1989-09-26
Also published as: CH484807A; ES362993A1; LU57770A1; US3610402A; BE726847A; NL6901006A; FR1565451A; DE1902733A1; NO132313B; GB1251893A; NO132313C

Abstract

A roll for transporting elongated ferro-magnetic bar-like products, includes a series of axially aligned magnetizing coils, and a magnetic circuit around each coil. Each magnetic circuit comprises an annular magnetic core within the coil, magnetic elements extending from the core on each side of the coil, and ring means surrounding the coil. The ring means includes a nonmagnetic portion of less width than that of the magnetic portion. The coils are supplied with direct current, and the roll is mounted on a non-magnetic shaft.

Description

United States Patent Tavernier et al.

1 51 Sept. 26, 1972 1 1 ROLL FOR DISPLACEMENT OF BAR- LIKE PRODUCTS [72] inventors: Georges L. P. Tavernier; Robert L.

Dubois, both of Maubeuge, France [73] Assignee: Usinor 22 Filed: July 22,1971

[21 I Appl. No.: 165,242

Related US. Application Data [(13] (.onlinuution-in-part of Scr. No. 799,081, Jan.

22, 1969, Pat. No. 3,610,402.

I30] Foreign Application Priority Data Jan 22,1968 France. .,.68l36931 52 us. 01. ..'....198/41, 226/93, 198/127 511 1111. c1 ..B65g 17/46 [58] Field of Search ..226/93, 190; 198/1 1,127;-

[56] References Cited I I UNITED STATES PATENTS 3,529,758 9/1970 Bernyetal. ......226/93 (ll/L 3,433,398 3/1969 Fadden et a1. ..226/93 FOREIGN PATENTS OR APPLICATIONS 1,157,120 7/1969 Great Britain ..226/93 Primary Examiner-Allen N. Knowles Assistant Examiner-Gene A. Church 5 7 ABSTRACT A roll for transporting elongated ferro-magnetic barlike products, includes a series of axially aligned magnetizing coils, and a magnetic circuit around each coil. Each magnetic circuit comprises an annular magnetic core within the coil, magnetic elements extending from the core on each side of the coil, and ring means surrounding the coil. The ring means includes a nonmagnetic portion of less width than that of the magnetic portion. The coils are supplied with direct current, and the roll is mounted on a non-magnetic shaft.

9 Claims, 3 Drawing Figures B a 9 /4 W 0' flil 5/4 1 4 PATENTEDsEm m2 SHEET 2 BF 2 R MM w oi. w TEM N m W v we 4 LL 7 g me. 50 GE Y B ROLL FOR DISPLACEMENT OF BAR-LIKE PRODUCTS This application is a continuation-in-part of copending application Ser. No. 793,081, filed Jan. 23, 1969, now U.S. Pat. No. 3,610,402.

The present invention relates to a roll whereby the movement of one or a plurality of ferro-magnetic barlike products, can be effected in a longitudinal direction. The invention has particular but not exclusive reference to rolled steel products such as bars, and angles.

Until now, in order to effect transport of products of this type, particularly when a number of the latter are massed together side-by-side in the form of a layer or nappe, motorized rolls have been used, these rolls being smooth cylinders bringing about the displacement of the products by friction. The lighter the products are, the less efficient are these motorized rolls and due to this fact have a lesser coefficient of adhesion so that a large number of them are necessary for permitting satisfactory transport. For example, with products 90 meters long, a roll is required every meter. This results in an unduly high initial cost and maintenance cost in relation to the power which is actually necessary.

Where the term layer is used in this specification and claims it is to be understood as a parallel-grouping or accumulation of bars or angles, such as are caused to move from the cooling bed to the transporting rolls in the customary manner.

On the other hand, it has been proposed to effect the movement of steel products with the aid of permanently magnetized rolls, but this solution causes operating difficulties which render it impractical, particularly in the case of products massed in the form of a layer.

In US. Pat. No. 3,529,758 the applicants have proposed effecting the conveyance of products by means of a roll of ferro-magnetic material adapted to be rotated by a motor and equipped with a magnetizing coil which can be supplied with direct electric current. In the embodiment described, the roll is formed by two adjacent steel bodies connected mechanically but isolated magnetically with, at the junction of the two bodies, a groove intended to receive the product. A transporter of this type is entirely satisfactory in the case of an individual product. However, the application to the case of products massed in the form of a layer raises difficulties which are obviated or mitigated by the present invention.

According to the present invention there is provided a roll for the transport of ferro-magnetic bar-like products lying side-by-side and forming a layer or a nappe, said roll being provided on its surface with areas of ferro-magnetic material separated by areas of nonmagnetic material of less surface area than the areas of ferro-magnetic material. The roll is also provided with magnetizing coils in its interior, the coils being supplied with direct electric current. Means are provided for rotating the roll.

Preferably, the roll in accordance with the invention comprises rings of ferro-magnetic material separated by rings of non-magnetic material, the latter rings having the same outer diameter, but lesser width than, the ferro-magnetic rings. Annular magnetizing coils are arranged in the rings, and the assembly is mounted on a coils during the course of rotation in order to be able to carry along products in the form of a layer, even of very great length, without them slipping. In particular, the products cocoperate with each other, by contact, in order to ensure the completion of the magnetic field circuit so that they are all attracted by the roll which they contact with an adequate force. Even an individualv product placed on a non-magnetic area assumes an unstable position and tends to slide slightly towards a ferro-magnetic area.

Moreover, when the coils are not supplied with current, the layer of products may be easily shifted on the roll. Finally, by studying the magnetic spectrum, it can be shown that the field is not disturbed by the presence of metallic plates adjacent to each roll, or between the rolls, functioning both as a frame and as a component which serves to disengage the ends of products from the roll.

Due to the high attractive force of an electro-magnetic roll according to the invention, it is possible, in a given installation, to considerably reduce the number of transporters, in relation to that necessary when conventional motorized rolls are used. The result of this is a considerable saving in the initial, and maintenance, cost of the installation.

A conveyor according to the invention is particularly advantageous when it is employed to move products which are side-by-side and parallel to each other, in a longitudinal direction. Since the products are attracted to the roll and do not slide with respect to it, they remain side-by-side and none moves ahead of the others.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a sectional view along the longitudinal axis of a roll according to this invention,

FIG. 2 is an enlarged fragmentary view of a portion of FIG. 1 showing the magnetic field lines; and

FIG. 3 shows diagrammatically in plan view an installation comprising rolls according to FIG. 1.

A roll according to the invention for the transport of elongated ferro-magnetic products is a smooth cylinder indicated generally by the reference numeral 1. The surface of the roll comprises areas of ferro-magnetic material separated by areas of non-magnetic material. In the embodiment shown these areas are formed by

steel rings

2, 3, 4, separated by rings, 5, 6, and 7 of lesser width, but of the same diameter as the

rings

2, 3, and 4. The

rings

5, 6, and 7 are non-magnetic material and in order that the wear of the roll surface is uniform, these rings can be made of non-magnetic steel of any type having substantially the same wear resistance as the magnetic material of

rings

2, 3, and 4.

Axially aligned annular magnetizing coils 8, 9, and are arranged in the rings 2-7. The assembly is completed by disks and 21,

end flanges

11 and 12, and coil-supporting

cores

13, 14, and 15, the disks, flanges, and cores being of magnetic material. The assembly is mounted on a common shaft 16 which is rotated by means of a motor shown at 17 in FIG. 3. The

shaft 16, of non-magnetic steel, is hollow and is formed with lateral openings18 accommodating electric wires supplying the coils with direct current. The interlocking of all the parts provided on the shaft 15 is effected by tie rods 19, for example three in number.

The coils are so designed, and the energizing current selected, to avoid overheating. The number of coils may be odd or even. Each coil, e.g., coil 9, is connected to the direct current supply in such a way that the direction of the magnetic field around it (see FIG. 2) is opposite to the direction of the magnetic field around a coil, e.g., coils 8 and 10, adjacent to it. I

Thus, around each of the coils 8, 9, and 10 is a magnetic circuit. For example, the magnetic circuit around coil 8 includes core 13, flange 11 and disk 20, and a ring means comprising magnetic rings 2 and non-magnetic ring 5. Ring 5 interrupts the magnetic circuit and constitutes the only interruption in that circuit. 4

FIG. 2 illustrates the magnetic field lines produced when direct current power is applied to coils 8-10, each of which comprises a wire wound around the longitudinal axis of shaft 16. The field present when no products engage roll 1 is shown with respect to coil 10. Due to the presence of non-magnetic ring 7, the field lines close outside the roll, as indicated at 24.

A single ferro-magnetic product resting on the roll changes the field, as indicated at 26. Product 25 causes a substantial modification of the reluctance of the magnetic circuit, around coil 9, at the point of contact of this product with the roll. The magnetic field lines follow a preferred path through product 25, as indicated by the heavier field line 26'. This causes product 25 to be attracted to the roll.

When a layer or nappe of products 27 engage roll 1, the magnetic field lines enter each product at its point of contact with the roll, and then travel from one product to the next, as indicated by the field lines around coil 8. Thus, each product 27 is attracted both to the roll and to the products contiguous with it. The amplitude of the field lines passing through the air is substantially decreased.

Since the presence of products 27 alters the magnetic field, as described above, the reluctance of the magnetic circuit and the width of non-magnetic rings 5-7 are chosen accordingly for bar-like products of minimal cross-sectional area, in order that the force of attraction alongthe length of the roll will be uniform. The magnetic field ismade very strong and as uniform as possible so that the layers of products are maintained in their initial positions, and since the stronger the field, the fewer the number of electromagnetic rolls needed.

In FIG. 3 there is shown an installation for the transport of layers of products, for example, for the transfer, toward a shear, of products coming from a cooling bed 28 of substantial length equipped with an alignment roll 29, such as described in the aforementioned U.S. Pat. No. 3,529,758. It comprises at least two electromagnetic rolls 1 and 1' according to the present invention, between which are provided idler rolls 30 having their axes parallel -to the shafts of the rolls 1 and 1 Preferably the non-magnetic areas 5-7 of roll 1 are not in alignment with the non-magnetic areas 5, 6 and 7' or roll 1 so that a product is necessarily in contact with a ferro-magnetic area on one or the other of the rolls. Consequently, every product is attracted to at least one of the rolls. Moreover, metallic plates 31 and 31', located at a slightly lower level than the upper generatrices of the rolls 1 and 1', are provided adjacent to each of the said rolls and downstream in relation to the direction of displacement G of the products. A single manual or automatic control 23 can be operated to simultaneously efi'ect the rotation of all the electromagnetic rolls through the intermediary of motors 17, and also the excitation of the coils with which these rolls are equipped.

The elongated products are slid one by one onto the transporter by means of suitable devices 33. When the number of products arranged on the rolls 1, 1', and 30 forms a layer of desired quantity the control 23 successively ensures the rotation of the electro-magnetic rolls 1 and 1 and the attraction of the products on these rolls, in such manner that the said products are carried along without slipping and are advanced over the idler rolls 30.

If the ends of the products are all aligned, they remain aligned in the course of their parallel movement. This is an advantage when, for example, the products are moving toward a shear, since this reduces the losses in material and as a result lessens the waste.

As an example, it may be indicated that with a cooling bed 90 meters long it is sufficient to use four magnetic rolls according to .the invention with 60 idler rolls for displacing layers of mild steel bars 90 meters long at 2.5 meters per second. Each layer may for example comprise 17 angles of 25 mm or 13 angles of 40 mm or 60 rounds of 12 mm or 38 rounds of 25 mm.

Each magnetic roll in this example has a generatrix of 1,000 mm length and a diameter of 260 mm. It comprises nine magnetic parts and eight non-magnetic parts and is provided with a speed reducer and a motor.

For a conventional installation as heretofore in use with the same hourly capacity, 64 individually motorized rolls would be necessary, the individual power of the control motors being 2KW, whereas the magnetic rolls according to this invention each require 9KW, with in addition 800 watts per roll in order to provide the magnetic force.

Thus, with equipment according to this invention, the total power is equal to 4 X 9 4 X 0.8 39.2 KW, whereas the standard equipment the total power would be 64 X 2 128 KW. The reduction of power for an installation with the same hourly capacity is therefore, according to this invention, percent.

Similarly, taking into account the fact that a magnetic roll according to this invention has a weight of 350 kg 180 kg. for the reducer 250 kg for the motor, and that an idler roll weighs kg, the total weight according to this invention is 8.5 tons, whereas with standard equipment using motorized rolls of the same diameter and length, weighing 410 kg including the motors, the total weight would be 26 tons, i.e., a reduction of approximately 67 percent.

It will be understood that the embodiments described have been given as examples and that they may have numerous modifications without departing from the scope of the present invention.

In this respect, the ferromagnetic material constituting the magnetic circuits may have the property of remanent magnetization when the DC supply is interrupted. This is particularly suitable when an electromagnetic roll according to the invention is used for transporting products suspended from the roll, the weight of the products being compensated by the attractive force, since the products continue to be attracted should the DC supply unexpectedly fail. In this case, the remanent magnetization may be suppressed by applying to the coils a suitable reversed DC supply.

What is claimed is:

l. A roll for transporting one or more elongated ferro-magnetic bar-like products in a longitudinal direction, said roll comprising a series of axially aligned magnetizing coils, means for supplying said coils with direct current, a magnetic circuit around each of said coils, each magnetic circuit including an annular magnetic core within and coaxial with said coil, magnetic elements at each side of said coil engaging said core, and ring means surrounding and coaxial with said coil and engaging said magnetic elements, said ring means being formed of magnetic material across most of its width but having a non-magnetic portion interrupting the magnetic circuit, and means for positively rotating the roll about the axis of said coils to longitudinally advance the products engaging it.

2. A roll as defined in claim 1 wherein said coils are connected to said direct current supply means in such a way that the direction of-the magnetic field around each coil is opposite to the direction of the magnetic field around a coil adjacent to it.

3. A roll as defined in claim 1 wherein said ring means comprises at least two rings, one of said rings being magnetic and the other non-magnetic, and said magnetic ring being wider than said non-magnetic ring, said non-magnetic ring constituting the only interruption of the magnetic circuit around said coil.

4. A roll as defined in claim 3 wherein said magnetic and non-magnetic rings are of materials having a substantially uniform resistance to wear.

5. A roll as defined in claim 1 including a non-magnetic shaft, coaxial with said coils, rotatably supporting the roll.

6. A roll as defined in claim 5 wherein said shaft is hollow, and said means for supplying direct current to said coils includes conductors within said shaft.

7. A roll assembly according to claim 1, including a metallic plate adjacent to and downstream of said roll in relation to the direction of movement of the products, said plate being at a level slightly lower than that of the upper generatrix of said roll.

8. An installation comprising at least two rolls according to claim 1 wherein the non-magnetic portions of one roll are out of alignment with the non-magnetic portions of the other roll in a direction perpendicular to their axes of rotation.

9. An installation according to claim 8 including idler rolls between said magnetic rolls, the axes of all said rolls being parallel.

Claims

1. A roll for transporting one or more elongated ferro-magnetic bar-like products in a longitudinal direction, said roll comprising a series of axially aligned magnetizing coils, means for supplying said coils with direct current, a magnetic circuit around each of said coils, each magnetic circuit including an annular magnetic core within and coaxial with said coil, magnetic elements at each side of said coil engaging said core, and ring means surrounding and coaxial with said coil And engaging said magnetic elements, said ring means being formed of magnetic material across most of its width but having a non-magnetic portion interrupting the magnetic circuit, and means for positively rotating the roll about the axis of said coils to longitudinally advance the products engaging it.

2. A roll as defined in claim 1 wherein said coils are connected to said direct current supply means in such a way that the direction of the magnetic field around each coil is opposite to the direction of the magnetic field around a coil adjacent to it.