US3217899A

US3217899A - Slab turning apparatus

Info

Publication number: US3217899A
Application number: US329732A
Authority: US
Inventors: Frank T Makowski
Original assignee: Magnaflux Corp
Current assignee: Magnaflux Corp
Priority date: 1963-12-11
Filing date: 1963-12-11
Publication date: 1965-11-16
Anticipated expiration: 1982-11-16

Description

Nov. 16, 1965 Filed Dec. 11, 1963 F. T. MAKOWSKI 3,217,899

SLAB TURNING APPARATUS 3 Sheets-Sheet 1 Fl 6- INVENTOR.

FRAN K T. MAKOWSKl ATTORNEYS Nov. 16, 1965 F. 'r. MAKOWSKI SLAB TURNING APPARATUS 3 Sheets-Sheet 2 Filed Dec. 11, 1963 ATTORNEYS Nov. 16, 1965 F. T. MAKOWSKI 3,217,399

SLAB TURNING APPARATUS Filed Dec. 11. 1963 3 Sheets-Sheet 3 INVENTOR. FRAN K T. MA KOWSKI F163 ATTOR NEYS United States Patent 3,217,899 SLAB TURNING APPARATUS Frank T. Makowski, Niles, Ill., assignor to Magnaflux Corporation, Chicago, 111., a corporation of Delaware Filed Dec. 11, 1963, Ser. No. 329,732 7 Claims. (Cl. 214-4) This invention relates to apparatus for turning slabs and more particularly relates to a chain sling turner characterized with provisions for turning slabs having substantially high width-to-thickness ratios. The apparatus of this invention is operable to efficiently turn such slabs in a controlled manner, the term slab being used herein in a generic sense to include any form of elongated object, pipe, rod, bar billet, bloom or the like having a cross-sectional shape or other characteristic with which the apparatus can be employed. The apparatus of the present invention is rugged in construction, durable in operation, simple in design and construction, easy to operate and can be advantageously employed in turning slabs of various configurations for a variety of purposes.

The turning apparatus of this invention was specifically designed for the non-destructive testing and inspection of slabs, wherein the slab is magnetized and magnetic particles are then distributed over the surface thereof, after which the slab can be inspected for flaws and imperfections as revealed by the orientation of the magnetic particles on the surface of the slab.

In such systems, the handling and inspection of large, heavy articles such as steel slabs which are many feet in length present substantial problems especially in respect to inspection because all surfaces must be presented to the view of the inspector. The problem is particularly serious where the slab is of polygonal cross-section with several side surfaces which must be inspected, and the slab itself is of such configuration as to have a high widthto-thickness ratio.

A chain sling turner has heretofore been proposed comprising a pair of horizontally spaced chain sprockets rotatably mounted on parallel axes on a support structure with an endless chain looped over the sprockets whereby the chain between the sprockets defines a catenary to form a sling for supporting and for turning a slab or other similarly heavy, elongated article. As the sprockets are rotated the chain travels in one direction from sprocket to sprocket in the path of the catenary, and a slab or similar articles supported in the valley or low point of the catenary is rotated, rolled or turned as the article tends to move up the ascending side of the catenary. A chain sling turner of this type is disclosed and claimed in Richard S. Gewartowski and Joseph L. Deibel co-pending application entitled Apparatus for Inspecting Billets and the Like, Serial No. 190,103, the assignee of which is the assignee of the present invention.

Such a chain sling turner satisfactorily rolls or turns slabs having a variety of configurations, but it is found that some slabs present difiiculties, particularly those having cross-sectional configurations wherein the width thereof is substantially greater than the thickness. If the surface of the slab having the greater or longer dimension is moved up the ascending side of the catenary of the sling, the article will merely continue to travel upwardly thereon without turning or rolling, and on the other hand, if the frictional forces are not great enough between the slab and the chain sling, the slab will merely slip on the chain, will remain on the ascending side of the chain and will not be turned or rolled with the result that not all of the various surfaces of the slab can be easily viewed for inspection purposes.

According to this invention an apparatus is provided for supporting and readily and efficiently turning slabs ice for inspection, the apparatus being particularly advantageous in the handling of slabs having relatively high width-to-thickness ratios.

An important feature of the invention is the provision of means for controllably kicking or tilting the slab while holding a lower portion of the slab in a manner to ensure rolling of slabs having a relatively high width-tothickness ratio.

A specific feature of the invention is in the provision of a chain sling turner for slabs having means for urging a leading surface of the slab as it rises on the ascending side of the catenary formed by the chain sling back toward the valley or center of the sling to roll or turn the slab, and further having means for resisting backward movement of a trailing surface of the slab in the sling to ensure rolling or turning of the slab.

Further features of the invention reside in the provision of a kicker arm having a kicker wheel pivotally mounted on the structure to selectively kick or tilt a slab being supported on the sling, and a stop arm pivotally mounted on the structure to operate in conjunction with the kicker arm for selectively impeding backward movement of a slab being tilted by the kicker arm to ensure pivoting of the slab on the sling for rotating and for turning the slab.

Many other features, advantages and additional objects will become manifest to those versed in the art from the detailed description of the invention which follows and the accompanying sheets of drawings in which a preferred embodiment of a chain sling slab turner assembly incorporating the principles of the present invention is shown by way of illustrative example.

On the drawings:

FIGURE 1 is a partially diagrammatic elevational view of a chain sling billet turner assembly constructed in accordance with the principles of the present invention with parts removed for the sake of clarity;

FIGURE 2 is similar to FIGURE 1 but with other parts removed in order to best illustrate the invention; and

FIGURE 3 is a partially diagrammatic plan view of the assembly of FIGURES 1 and 2 and includes in dashed lines a fragmentary view of exemplary associated apparatus in the art association of non-destructive slab testing apparatus.

As shown on the drawings:

The chain sling turner assembly of the instant invention may find utility in turning and rolling slabs for a variety of purposes. It is well to appreciate at the outset that the problem of selectively supporting and turning slabs for inspection purposes or for other reasons presents diificulties not found in most article handling operations because of the great size and mass of the article with which I am concerned in the instant invention. Articles such as large steel slabs, blooms and the like may have lengths of up to 40 feet or more. The Weight of such slabs may often be in the order of several thousand pounds or even several tons and the cross-sectional dimensions of the slabs may be as great as 15 inches or more. Accordingly, the problems of handling articles of such tremendous size and weight differ from the problems of handling smaller and lighter objects.

In addition, in some instances, for example, in some article inspection operations, it is most desirable to have at least one complete surface of the article free of all obstructions for convenient visual inspection of the surface of the article, and once again such considerations present further problems in the handling of the articles.

One field of art wherein the present invention finds particular utility resides in the field of non-destructive testing of magnetizable slabs and for the purpose of illustrating one important art association for the present invention, and not for the purpose of limiting th or utility of the present invention, the description thereof will be made in conjunction with one form of apparatus used in the non-destructive testing of magnetizable slabs.

Having reference to FIGURE 3, an installation of apparatus embodying the invention is indicated at reference numeral and is depicted of a type adapted to handle and process for inspection slabs of large size, and more particularly slabs having cross-sectional dimensions up to inches and being up to 16 feet in length, although itwould be readily appreciated that by proper selection in constructing the apparatus there is no apparent limit upon the range of practical or commercial size ranges for which the apparatus may be adapted.

The apparatus 10 is particularly suited for non-destructive testing of magnetizable slabs and may provide a plurality of stations or operational areas, including a magnetizing and bath applicator station (not shown) where the slab is magnetized to provide a substantially uniform magnetic flux over its entire surface except as distorted by defects within the slab, whereupon magnetic particles from a bath containing such particles deposited on the slab are attracted to the regions of distortion of the magnetic field and thereby indicate the presence of defects. Thereafter the slab with the magnetically oriented particles thereon is transferred transversely by means of large, pivoting transfer arms as at 11 to an inspection station indicated generally by the reference numeral 12 Where a person skilled in this art visually inspects the treated slab and applies thereto markings to identify the nature and location of detected flaws or imperfections, and any other identification, advisory, code and like markings that may be desired. After inspection has been completed, the inspected slab is then transferred from the inspection station 12 to an unloading station (not shown).

The transfer arms 11 may conveniently be adapted to load and unload slabs into and out of the inspection station 12 and for this purpose may be pivotally mounted on a common shaft 13 which is supported for rotation on a frame assembly indicated generally at 14. The inspection station 12 comprises a plurality of chain sling billet turner assemblies indicated generally at reference numeral 16 which are spaced along the length of the testing apparatus 10 adjacent the shaft 13. Two assemblies 16 are illustrated in FIGURE 3, but it will be understood that the number and spacing of the slab turner assemblies 16 Will depend upon the size of the apparatus 10 and the ranges of length of the slabs to be inspected thereon.

One arrangement of transfer arms 11 for loading and unloading the inspection station 12 is disclosed in Jack A. Peterson and Joseph L. Deibel co-pending application entitled Rapid Transverse Unloading Mechanism, Serial No. 243,798, which is assignedto the assignee of the present invention. In this earlier application the transfer arms 11 are adapted to gently lower a magnetized slab into the slab turner assemblies 16 which comprise the inspection station 12, and after the slab has been inspected, to lift the inspected slab out of the inspection station for transfer to an unloading station. Since the testing apparatus 10 and the arrangement of transfer arms 11 does not form a part of the present invention, additional details thereof will be omitted for the sake of brevity.

Referring to FIGURES l and 2, each of the slab turner assemblies 16 comprises a pair of horizontally spaced vertically aligned

rotatable shafts

17 and 18 situated on horizontally extending parallel axes and journalled for rotation on a pair of horizontally spaced vertically upstanding plate members 19 and 21) which are bottomed respectively on a floor surface (not shown). As seen in FIGURE 3, the

shafts

17 and 18 each have mounted thereon for co-rotation therewith a pair of axially spaced driven

chain sprockets

21 and 22 and a driver chain sprocket 23. For supporting and for turning a slab B about it longitudinal axis, a pair of

chains

24 and 26 are wrapped respectively over each of the pairs of driven

sprockets

21 and 22. The

chains

24 and 26 are loosely trained over their corresponding sprockets to form a sag between the sprockets which, when a slab is not being supported thereon, takes the shape of a catenary having an essentially descending side 27 and an ascending side as at 28. The

chains

24 and 26 are endless, and in order to maintain a predetermined length thereof between their corresponding supporting sprockets, a pair of

spacer sprockets

29 and 30 are mounted for rotation on a shaft 31 journalled for rotation in a journal member 32 which is connected in fixed assembly to the plate members 19 and 2t) by means of a horizontal frame member 33.

In order to provide simultaneous rotation of

shafts

17 and 18 to operate

chains

24 and 26, a driver chain 34 is trained over the

driver sprockets

23, 23 as well as sprocket 36 mounted for co-rotation on a driver shaft 37 which is mounted in a journal block 38 connected in fixed assembly to the

plates

19 and 20 by means of a plate member 39. The driver shaft 37 may be driven by means of any suitable power source, for example, an electric motor (not shown).

In order to maintain proper tension in the endless driver chain 34, and in order to maintain the top portion thereof trained over

sprockets

23, 23 substantially below the catenary formed by driven

chains

24 and 26 so as to avoid obstruction with a slab supported thereby, the top portion of the chain 34 is trained under an idler sprocket 40 carried on a shaft 41 which is mounted for rotation on journal member 42.

It will be apparent that the driver shaft 37 may extend the entire length of and be co-extensive with the inspection station 12 and a single source of power may be utilized for driving all of the slab turner assemblies 16 through shaft 37, and on the other hand, each of the assemblies 16 may comprise individual driver and driven shafts which may be operated individually by independent motor means. In any event it will be appreciated that all of the assemblies 16 will be operated simultaneously for rotating a slab supported in the catenaries or chain slings defined by all of the driven

chains

24 and 26.

As shown in the drawings, the catenary defined by the respective chain slings is upwardly opening and supports the slab B essentially from below, in virtue of which an inspector situated adjacent the inspection station 12 has a clear, unobstructed view of at least one complete surface of the slab, for example, surface 13,.

In operation, after a complete surface of the slab has been inspected for flaws and other imperfections the driver shaft 37 is selectively rotated by means of suitable motor switch means (not shown) which may be under the control of the inspector to rotate the driven

sprockets

21 and 22 for moving

chains

24 and 26 essentially through the path of their respective catenaries. If the slab being inspected is of a generally circular cross-section configuration, the travel of the chain slings will merely rotate the slab in the valley or at the low portion of the catenary. Similarly, if the slab is of an essentially polygonal crosssection configuration, the slab will merely rotate about its longitudinal axis in the valley of the chain slings. As a result, after one complete surface of the slab has been inspected, the inspector can selectively control movement of the chain slings to rotate the slab until another surface thereof is facing essentially upwardly for completely free and unobstructed visual observation thereof.

For inspecting slabs having essentially circular crosssections or polygonal slabs having essentially square crosssectioned dimensions, movement of the chain slings themselves is sufiicient to roll or turn the slabs for inspection of the various surfaces thereof. However, in the case of slabs having relatively high width-to-thickness ratios, the travel of the chain slings themselves through essentially the path of their respective catenaries is not generally satisfactory for rolling or turning the slabs.

For example, referring to FIGURES 2 and 3, the slab B has a relatively high width-to-thickness ratio, as indicated by the relative dimensions of sides or surfaces B and B to the smaller dimensions of surfaces B and B The width of the slab as determined by the length of sides B and B is proportionally greater than the thickness of the slab as indicated by the length of the sides B and B In these circumstances, movement or travel of the chain slings is not sufficient, in itself, to roll or rotate the slab B.

Assuming that chain slings 24 and 26 are unwinding from the driven

sprockets

21 and 22 mounted on the plate member 19 and are winding up on the driven sprockets carried by the plate member 20, the slab B, in the position illustrated in FIGURES 2 and 3, will begin to climb up on the ascending side 28 of the catenary defined by the chain slings. This is, of course, assuming that the frictional force between the surface B of the slab and the chain slings is sufficient to restrict relative movement therebetween. In the event that such frictional force is not sufficient, the slab B will merely slip relative to the chain slings, and the slab will remain in the valley of the catenary in the position illustrated in the drawings. It is to this problem of rotating slabs having high width-to-thickness ratios in the chain sling assemblies that the instant invention is particularly directed.

It is apparent that in order to turn the slab the center of gravity thereof as indicated by the reference character C.G. must be moved to the left side of the lowest point of the valley of the chain slings as viewed in the drawings. To this end, each of the slab turner assemblies 16 may be provided with a slab kicker arm member indicated at 43 which is, in the exemplary embodiment illustrated, generally V-shaped and situated normally below the valley of the catenary of the chain slings 24 and 26. It will be appreciated, however, that other configurations of the kicker arm member 43 may advantageously be utilized and this member may be a straight member, for example. One leg 44 of the illustrative kicker arm 43 is pivotally mounted on the plate member 19 by means of a rotatable shaft 46 journalled for rotation on a bearing member 47 which is securely fastened to the plate member 19 by any suitable means, for example, a plurality of fasteners as at 48. In the illustrated embodiment, a circularly shaped slab kicker wheel 49 is rotatably mounted at the distal end of leg 50 by means of a rotatable shaft 51 and serves to minimize friction and wear on the parts. It will become apparent, however, that the kicker wheel 49 may assume other configurations, and may for that matter be entirely eliminated and in accordance with the principles of the invention.

In order to operate the kicker arm 43 for pivotal movement thereof, a pressurized fluid operated hydraulic cylinder as at 51 is connected at one end thereof as at 52 to the arm 43 and at its opposite end 53 to a rotatable shaft 54. A journal member 56 rotatably mounts the shaft 54 and is connected, in turn, in fixed assembly to the plate member 19 by means of a flange bracket as at 57.

Suitable means may be provided for selectively supplying a flow of pressurized fluid to the hydraulic cylinder 51, for example, an electric motor driven fluid pump (not shown). Suitable control means may also be provided for controlling the operation of cylinder 51 to permit selective control thereof by the inspector at the inspection station. It will be understood, of course, that other means may be provided for pivotally actuating the kicker arm 43, of which the hydraulic cylinder 51 is merely exemplary.

In operation, after the slab B has been moved by traveling

chain slings

24 and 26 to a position illustrated -in FIGURES 2 and 3, the hydraulic cylinder 51 may be selectively controlled to telescopically extend a driving shaft thereof as at 58 to pivot the kicker arm 43 counterclockwise about the shaft 46. As noted in the drawings, the kicker wheel 49 is normally positioned below and .on the ascending side of the chain slings, and as the kicker arm 43 is rotated or pivoted in a counterclockwise direction the kicker wheel 43 will be moved upwardly and toward the center of the chain slings to a position as at 58. As seen in FIGURE 1, the kicker arms are horizontally offset relative to the chain slings 24 and 26 such that as the kicker wheel attains a position as shown at 58 it will engage a leading surface of the underside B of the slab B, Continued counterclockwise rotation of the kicker arm 43 will tend to rotate the engaged leading surface, that is, a surface situated upwardly on the ascending side of the chain sling, in a counterclockwise direction about the surface B As the center of gravity C.G. of the slab is moved leftwardly of the low point of the valley of the chain sling as viewed in the drawings, the slab will turn or fall over such that surface B thereof will rest on the descending side 27 of the chain slings.

It will be appreciated that when the slab B is positioned as illustrated in FIGURES 2 and 3, the surface B presents a clear and unobstructed view to an inspector situated on the right-hand side of the plate member 20 as viewed in the drawings. After the kicker arm 43 has rolled the slab on the chain slings, surface B will rest on the descending side 27 of the chain sling, providing a clear View of surface B Further movement of the chain sling will thereupon move the slab into a position essentially as illustrated in FIGURES 2 and 3, but now surface B canbe observed by the inspector, and so forth, until all four surfaces of the slab have been inspected for flaws and imperfections.

In the embodiment illustrated it can be assumed that the chain slings 24 and 26 will provide sufiicient frictional forces between the slab and the slings to preclude relative movement therebetween. In these circumstances it will be appreciated that the chain slings could be selectively moved simultaneously with the kicker arm 43 such that the pivot point of the slab B will not slide or slip on the chain slings to prevent wear thereto. On the other hand, assuming that the slings constitute material having little frictional resistance, as the slab is rolled or turned the pivot point of the slab will merely slide or slip along the chain slings, without wear resulting therefrom.

In order to alleviate harmful impact to the descending side 27 of the chain slings as the slab B rotates and drops thereto, suitable means are provided for receiving the rotated slab and for gently lowering the slab to the descending side 27. Referring to FIGURE 1, a slab stop arm 59 is pivotally mounted on a shaft 60 supported for rotation in a journal member 61 which is connected in fixed assembly to plate

members

19 and 20 by means of a horizontal frame member 62. A hydraulic cylinder 63 is pivotally connected to plate member 20 as at 64 at one end thereof and at its opposite end is pivotally connected to the stop arm 59 by means of a bearing member as at 66. The hydraulic cylinder 63 may also be of the pressurized fluid actuated type and it will be understood that suitable means are provided for selectively actuating cylinder 63 in a manner similar to cylinder 51.

The stop arm 59 mounts a slab receiving plate 67 at the distal end thereof and normally the stop arm 59 and the receiving plate 67 are situated below and on the descending side of the catenary defined by the chain slings 24 and 26. As kicker arm 50 is rotated counterclockwise to pivot the slab, the stop arm 59' may be simultaneously and selectively rotated clockwise such that the receiving plate 67 moves upwardly above the chain slings to receive that surface of the slab being dropped to the descending side of the slings and can then be pivoted slowly in a counterclockwise direction to gently lower the slab to the descending sides of the slings.

In addition, the stop arm 59 may serve another useful function in a situation where the frictional resistance between the slab and the chain slings is, not suffic' to preclude relative movement therebetween. In the circumstances, before the kicker wheel 49 engages a leading surface of the slab the stop arm 59 may be pivoted sufliciently such that the receiving plate engages a trailing surface of the slab, that is, a surface of the slab in the direction of the descending side of the slings, to preclude backward movement of the slab relative to the slings as the kicker arm rolls or turns the slab. Wear on the chain slings and the maintenance problems attendant therewith are thereby reduced accordingly.

Referring to FIGURE 3, it will be appreciated that the kicker arms 43 and the stop arms 59 can conveniently be situated on the same side of the slab turner assembly 16 as illustrated in the lower portion of the drawing, or alternatively can be situated on either side of the slab turner assemblies as illustrated in the upper portion of the drawing. In addition, suitable control mechanisms may be provided for simultaneous operation of the corresponding kicker arms and stop arms and actuation thereof can be selectively controlled by any suitable means by the inspector situated at the inspection station.

It is noteworthy that it is ordinarily desirable that the curve of the catenary or sag of the chain 24 be substantial to obtain the desired flexibility in handling of slabs of various shapes, but in SOme cases the curve may be so reduced as to be substantially eliminated, as by providing chains of such length as to define a straight line between the sprockets, and the complete slab rolling and turning action can be provided by the kicker arms. The chains can then be used (if used at all) only for properly positioning the slab in relation to the kicker arms.

It will be understood that operation of the movement of the chain slings as well as the kicker arms and stop arms may be arranged to be conveniently controlled by manual or automatic control devices situated at the inspection station or at other suitable control headquarters.

Although minor modifications might be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably come Within the scope of my contribution to the art.

I claim as my invention:

1. Apparatus for supporting and for turning a slab comprising, in combination,

a support structure,

a slab supporting and turning sprocket chain,

a pair of sprockets on spaced parallel stationary axes and horizontally aligned with said chain trained thereover and affording a catenary therebetween providing an upwardly opening slab supporting sling,

means rotatably supporting said sprockets on said support structure,

means for selectively driving said sprockets and said chain for moving a slab toward the ascending side of the catenary, and

means for selectively engaging and for raising a leading surface of the supported slab off of said sling to pivot the slab about a trailing surf-ace thereof being supported by the sling to turn and to reposition the slab relative to the sling.

2. Apparatus for supporting and for turning a slab comprising, in combination,

.a support structure,

a slab supporting and turning sprocket chain,

a pair of sprockets on spaced parallel axes and horizontally aligned with said chain trained thereover and affording a catenary therebetween providing an upwardly opening slab supporting sling,

means rotatably supporting said sprockets on said support structure,

means for selectively driving said sprockets and said chain for moving a slab supported on said chain toward the ascending side of the catenary,

g a slab kicker arm having a slab engaging surface thereon, and

means connected to said kicker arm and to said support structure for selectively moving said arm relative to said sling to engage the slab engaging surface of said arm with the supported slab on the ascending side of said sling to move a leading surface of said slab off of said sling and in the direction of the descending side of said catenary to pivot the slab about a trailing surface thereof supported by the sling for turning and for repositioning the slab relative to the sling.

3. Apparatus for supporting and for turning a slab comprising, in combination,

a support structure,

a slab supporting and turning sprocket chain,

means rotatably supporting said sprockets on said support structure,

a slab kicker arm having a slab engaging surface theremeans connected to said kicker arm and to said support structure for selectively moving said arm relative to said sling to engage the slab engaging surface of said arm with the supported slab on the ascending side of said sling to move a leading surface of said slab off of said sling and in the direction of the descending side of said catenary to pivot the slab about a trailing surface thereof supported by the sling for turning and for repositioning the slab relative to the sling,

a slab stop arm having a slab engaging surface thereon, and

means connected to said stop arm and said support structure for selectively moving said arm relative to said sling to abut the slab as it is being pivoted by said kicker arm and to lower the slab gently to the sling.

4. In a chain sling slab turner apparatus having a support structure, a slab supporting and turning sprocket chain, a pair of sprockets on spaced parallel axes and horizontally aligned with the chain trained thereover and affording a catenary therebetween providing an upwardly opening slab supporting sling, means rotatably supporting the sprockets on the support structure, and means for selectively driving the sprockets and the chain for moving a slab supported on the chain toward the ascending side of the catenary,

the improvement of a slab kicker arm pivotally mounted on the support structure,

a slab kicker wheel mounted on the distal end of said kicker arm and normally positioned below the sling,

means including hydraulic cylinder means for selectively pivoting said kicker arm to move said wheel upwardly above said sling to engage a surface of a slab supported on the sling at the ascending side of the catenary to rotate the slab on the sling,

a slab stop arm pivotally mounted on the support structure,

a slab receiving plate mounted on said stop arm and normally positioned below the sling, and means ineluding hydraulic cylinder means for selectively pivoting said stop arm to move said receiving plate above the sling on the descending side thereof to receive a slab being rotated by said slab kicker arm and then to lower the slab gently to the sling.

5. Apparatus for supporting and for turning a slab having a relatively high width-to-thickness ratio comprising, in combination,

a support structure,

a pair of horizontally spaced sprockets mounted for rotation on said support structure,

a chain having spaced portions thereof trained respectively about said sprockets to form a sling substantially in the shape of a catenary between said sprockets to support a slab thereon,

driving means connected to said sprockets for rotating said sprockets to wind said chain from one of said sprockets to the other to move the chain substantially in the path of the catenary for moving the supported slab in the direction of said other of said sprockets,

a slab kicker arm pivotally mounted on said support structure, and

means for pivoting said kicker arm to engage a leading surface of the slab at the ascending side of said sling and to turn to reposition the slab on said sling.

6. Apparatus for supporting and for turning a slab having a relatively high width-to-thickness ratio comprising, in combination,

a support structure,

a chain having spaced portions thereof wound respectively about said sprockets to form a sling substantially in the shape of a catenary between said sprockets to support .a slab thereon,

driving means connected to said sprockets for rotating said sprockets to wind said chain from one of said sprockets to the other to move the chain and a slab supported thereon substantially in the path of the catenary in the direction of said other of said sprockets,

a slab kicker arm pivotally mounted on said support structure,

means for pivoting said kicker arm to engage and to 10 prising, in combination,

a support structure,

a slab supporting and turning sprocket chain,

a pair of sprockets on spaced parallel stationary axes and horizontally aligned with said. chain trained thereover affording a catenary therebetween providing and upwardly opening slab supporting sling,

means rotatably supporting said sprockets on said support structure,

means for driving said sprockets only co-rotatably for moving a slab toward the ascending side of the catenary, and

means for engaging and for raising a leading surface of the supported slab oil of said sling to pivot the slab about a trailing surface thereof being supported by the sling to turn and to reposition the slab relative to the sling.

References Cited by the Examiner UNITED STATES PATENTS 1,962,772 6/1934 Hull. 2,271,213 1/ 1942 Weidner. 2,527,024 10/1950 Mitchell. 3,154,119 10/1964 Saison 143-102 X FOREIGN PATENTS 1,003,081 2/ 1957 Germany.

MARVIN A. CHAMPION, Primary Examiner.

Claims

1. APPARATUS FOR SUPPORTING AND FOR TURNING A SLAB COMPRISING, IN COMBINATION, A SUPPORT STRUCTURE, A SLAB SUPPORTING AND TURNING SPROCKET CHAIN, A PAIR OF SPROCKETS ON SPACES PARALLEL STATIONARY AXES AND HORIZONTALLY ALIGNED WITH SAID CHAIN TRAINED THEREOVER AND AFFORDING A CATENARY THEREBETWEEN PROVIDING AN UPWARDLY OPENING SLAB SUPPORTING SLING, MEANS ROTATABLY SUPPORTING SAID SPROCKETS ON SAID SUPPORT STRUCTURE, MEANS FOR SELECTIVELY DRIVING SAID SPROCKETS AND SAID CHAIN FOR MOVING A SLAB TOWARD THE ASCENDING SIDE OF THE CATENARY, AND MEANS FOR SELECTIVELY ENGAGING AND FOR RAISING A LEADING SURFACE OF THE SUPPORTED SLAB OFF OF SAID SLING TO PIVOT THE SLAB ABOUT A TRAILING SURFACE THEREOF BEING SUPPORTED BY THE SLING TO TURN AND TO REPOSITION THE SLAB RELATIVE TO THE SLING.