US2877008A

US2877008A - Slatted framework and method of making

Info

Publication number: US2877008A
Application number: US554887A
Authority: US
Inventors: Mattia Andrew D De; Jr Nick Pusta
Original assignee: Rolock Inc
Current assignee: Rolock Inc
Priority date: 1955-12-22
Filing date: 1955-12-22
Publication date: 1959-03-10
Anticipated expiration: 1976-03-10

Description

March 10, 1959 A. D. DE MATTIA ETA'L 23 SLATTED FRAMEWORK AND mamon" or MAKING- 2 Sheets-Sheet 1 Filed Dec. 22, 1955 I" 4 ufii iiiiii iiiiiii wi i iiiiiiiiiiiii INVENTORS MW 93. @efl'lahbla.

ATTORNEY March 10, 1959 A, D, DE MATTIA ET'AL 2,877,008

SLATTED FRAMEWORK AND METHOD OF MAKING Filed Dec. 22, 1955 2 Sheets-Sheet 2 5& a uys NVENTORS find/bear an. sue/mam M ubba c'f.

ATTORNEY SLATTED FRAMEWORK AND METHOD OF MAKING Application December 22, 1955, Serial No. 554,887

13 Claims. (Cl. 263-47) This invention relates to a framework of slatted construction and more particularly to an open type of constraining frame of such construction for armoring wire mesh or other perforate baskets such as are intended to contain metallic work parts and carry them through a tunnel type of heat treating furnace and subsequent quenching or other processing zone. The invention also resides in new methods of fabricating the improved framework.

The type of constraining frame herein chosen for illustrating the invention closely flanks and surrounds a wire mesh basket to form a rugged perforate work carrier comprising the framework and the basket inserted therein as a liner.

Heretofore in securing rails of sheet metal in crossing relation to-posts of sheet metal for making a framework of slatted construction, reliance has been placed on welding or riveting as a fastening means at the crossing points of the rails and posts. Welding produces positive fixity of the rails to the posts without opportunity for any relative movement or give between them. Welding so employed tends to make the sheet metal brittle at or near the welded joints. As a result, uneven stresses have been set up in such welded structures by the very high temperatures and subsequent quenching to which they are subjected in the heat treatment of contained metallic work pieces. The maximums of high temperature are not reached in all parts of the frame structure atthe same time and this causes distorting strains capable of rupturing the posts, therails, or the welding, with consequent loss of constraining strength to the carrier and shortening of its vuseful life.

An object of the present improvements isto join the rails and posts of a slatted framework in a dependable manner that requires neither welding nor other kind of extraneous fastening means at their crossing points and thatpermits a positively restricted degree of relative movemenflbetween them. Thisavoids the disadvantages of welded joints particularly if gas welded and results in a'carrier that possesses superior strength and durability under abusive conditions of use because of being practically immune to damage byuhea'ting and subsequent quenching. I

Indicative of the principles of construction underlying the present improvements, and of methods of incorporating such improvements in a slatted framework, the accompanying drawings illustrate successful embodiments of the improved construction explained in greater detail in'the following description having reference to the drawings in which:

Fig. l is an isometric view of a constraining frame made of posts and rails interengaged in laced relationship according to the invention without the necessity of welding.

Fig. 2 represents a wire mesh basket for holding and carrying'work parts .insertable as a liner in the constrainingv frame of Fig. 1.

Fig. 3 shows partially broken away a rigid base grid 2,877,008 Patented Mar. 10, 1959 usable with and separable from the frame of Fig. 1, and adapted to underlie the wire mesh basket of Fig. 2 for support of the latter against sagging so as to serve as a sledding base for the carrier as a whole.

Fig. 4 is a plan view of the separable structures of Figs. 1, 2 and 3 related as they are commonly used together in a heat treating furnace, the wire mesh liner basket being broken away.

Fig. 5 is a fragmentary view drawn on an enlarged scale taken in section on the plane 5-5 in Fig. 4 looking in the direction of the arrows.

Fig. 6 is a correspondingly enlarged fragmentary view taken in section on the plane 6-6 in Fig. 4 looking in the direction of the arrows.

Fig. 7 is an outside elevation of interlaced crossing slats before being bent to form a corner of the frame.

Figs. 8 and 9 are plan views of the parts in Fig. 7 respectively before and after they are bent to form a corner of the frame of Fig. 1.

Fig. 10 shows a modified relationship of interlaced flat slats.

Figs. 11 and 12 are plan views of the parts in Fig. 10 respectively before and after they are bent to form a corner post of the frame.

Fig. 13 shows a modified piercing of the post slats for forming the threadable loops.

Whereas a framework such as 12 embodying the present invention may have various uses, it is illustrated in Fig. 1 in a form particularly suited to the armoring constraint of a wire mesh basket 13 of the type indicated in Fig. 2 which fits inside the frame as shown in Fig. 4 in the manner of a liner.

Basket 13 may be attached to frame 12 by means of staples 14 passing through holes 151m the top and/or bottom rail 16 of the frame of Fig. 1 and clenched over' against the inner surface of the wire mesh fabric from which the basket is formed. However the fastening strength of staples 14 alone is not depended upon as the sole means by which the liner 13 can be upheld within the frame 12 when heavily loaded with work pieces destined for heat treatment. To prevent sagging of the bottom of the basket and for sledding the carrier along the floor of or on a metal belt through a tunnel type of heat treating furnace a base grid 17 may be employed on which the bottom of basket 13 may rest while the bottom ends of the corner posts 18 of frame 12 are received freely into corner spaces 19 of the grid 17. Figs. 5 and 6 best show-a preferred height relationship of the bottom ends of the corner posts and the bottom of the basket to the vertical height of grid 17. Suchygrid may be cast as an integral rigid metallic structure or made in' fabricated form. Neither it nor the liner basket is claimed to be new other than as. herein shown to be correlated with the presently improved construction of constraining frame. In frame 12 a top rail 16 and a bottom rail 20 are seen to comprise continuous slats or flat strips of metalcontinuous around the rectangular shape of the frame and whose free ends meet and overlap at '21 where'they are secured together by one of the staples 14 and/or by welding or any other suitable means.

Before the rails 16 and 20 are bent to form a rectangle, there is strung along both rails a series of flat metallic crossing slats 25 which when bent according to the invention are to constitute the corner posts 18 for frame 12. Additional slats 26 can be of any suitable number and spaced along the span of the rails between the corner posts.

Each of slats 25 and 26 has offset from the flat of its broadside surface one or more loops 27 as shown in Figs. 7 and 8 comprising a component section or sections of the width of the slat bowed away from and back into flush alignment with an adjacent component section or sections of the width of the slat. Through all of such loops the rails 16 and 29 are laced while the slats 25 and 26 remain fiat.

After, say, four of the slats 25 have thus been strung on the rails 16, 20, with or without the presence of intermediate slats 26, each slat 25 together with its interlaced rails 16, is bent lengthwise of itself and crosswise of the rails to angular shape as shown in Fig. 9 whereby to form the corner posts 18 appearing in Fig. 1. There are thus produced at the corners of the framework conforming angular bends in a single one of the component post sections and in the rail. After such bending operation the corner posts 18 can not be displaced from their positions lengthwise of the rails 16 and yet, depending somewhat upon the tightness or looseness of the fit of the rails 16, 20 within the loops 27, there is permitted more or less freedom for positively limited slight relative movement between the rails and the corner posts at their crossing points. Such freedom or give proves sufficient to accommodate any strains that can be set up in the sheet metal of the frame by the simultaneous occurrence of uneven temperatures in its different parts and prevents the tearing apart or fracture of the rails or posts at their points of crossing engagement. Despite the preferred presence of slight possible looseness in the sliding fit of the rail 16 or 20 in the

loop

27 or 27 of the post 18, the angular bend in each of the rails reinforces the rigidity of the conforming angular bend in the post 18 with which it is crossingly interlaced. Thus the present improvements obviate troubles from deterioration and short life which heretofore have characterized constraining frames of the kind here concerned.

In Figs. 10 and 11 a loop 27 is offset from the fiat of the slat Loop 27" comprises a single central component section of the width of the slat and results in a modified relationship of rail and corner post to the angle at which they are together bent such as is shown in Fig. 12.

In Fig. 9 it may be said that the two loops 27 are olfset from the broadside surface of post 18 and that the post has a corner forming angular bend extending lengthwise of the post and abutting a corresponding angular bend extending crosswise of an overlapping portion of rail 16, whereas in Fig. 12 the lengthwise angular bend in post 18' extends through the single loop 27'.

In Fig. 12 a post slat 25a is shown to be so pierced as to form slots 28' having substantial width throughout their lengths instead of only at their ends 28 as in Figs. 7 and 10.

Before bending the slats 25 to form corner posts they may or need not be lightly tacked to the rails as by spot welding to assist in maintaining their designed relative placement during the bending operations only.

Practical but non limiting dimensions of slats 25 for forming corner posts is a width of 2% having a loop forming component 27 that is about 1%" wide when-the metal is a high nickel chrome alloy about /s" thick. A suitable width for the rail forming slats is l or more if the rails are of a similar thickness and kind of metal. Parts having the foregoing approximate sizes are suitable for making a carrier roughly measuring overall about 30 long by 22" wide by 3 /2" high. Smaller frames or much larger and heavier frames made from thicker and wider slats of metal can partake as well of the benefits of these improvements.

The corner posts which may be three, four or more in number may be bent to other than a right angular formation or may be bent to a curved formation instead of at a sharp angle whereupon the carrier as a whole may be round or oval or have more or less than four straight sides. Various other departure, from the particular shapes and arrangements herein chosen to illustrate the invention may be made within the scope and intended coverage 'of the. appended claims which therefore are to 4. be interpretered in the broadest sense of the terms employed therein to define the invention.

We claim:

1. An encompassing framework of cross members comprising a plurality of upright sheet metal corner posts each having at least one component section of its width bowed away from and back into flush alignment with an adjacent component section of said width whereby to form a closed loop, and at least one cross rail narrower than the length of said posts extending through said closed loops of said posts in crossing and overlapping relation to both of said component post sections, a single one of said component post sections and said over lapping rail having mutually conforming angular bends forming corners of said framework.

2. An encompassing framework of cross members as defined in claim 1, in which the said loop flanks the corner of the said angular bend in the said post.

3. An encompassing framework of cross members as defined in claim 1, in which there are two of the said loops on respectively opposite sides of the corner of the said angular bend in the said post.

4. An encompassing framework of cross members as defined in claim 1, in which the said conforming angular bends at the corners of the framework occur entirely outside the said loop forming component section of the post width.

5. An encompassing framework of cross members as defined in claim 1, in which the said angular bend in each of the said posts extends lengthwise of the post and the said conforming bend in the said rail extends crosswise the rail.

6. An encompassing framework of cross members as defined in claim 1, in which the said conforming angular bends at the corners of the framework occur within the said loop forming component section of the post width.

7. An encompassing framework of cross members as defined in claim 1, in which there are a plurality of cross rails spaced vertically apart edgewise and each of said rails continues past all of the said posts in a complete circuit and has its free ends united to form a closed band, and each of the said posts has a plurality of the said loops spaced apart lengthwise of the post occupied respectively by said rails.

8. A carrier for work pieces to be heat treated comprising in combination with a basket having relatively weak perforate walls, an encompassing framework as defined in claim 7 closely flanking the outside surface of the walls of said basket, and mechanical fasteners extending through the said rails of said framework and through said walls of the basket binding the latter to said rails.

9. A carrier for Work pieces to be heat treated as described in claim 8, together with a grid comprising a base forming frame bordering a space partitioned to form corner openings and underlying the said basket, said corner openings being occupied by the bottom ends of the said corner posts.

10. The method of fabricating an open frame of bent metallic slats which comprises the steps of, offsetting in broadside direction at least one of adjacent components of the width of a flat faced post slat of sheet metal so that said component forms a loop standing out from the surface of said slat, lacing a fiat faced sheet metal bend sustaining rail slat lengthwise with a sliding fit through said loop in crossing relation to the length of said post slat, and simultaneously bending both said post slat and said rail slat lengthwise of said post slat and crosswise of said rail slat in the common crossing area of said slats while maintaining the flat faces thereof in conforming overlapping relation, thereby to interlock said slats in a manner permitting but positively limiting slight shifting of said rail slat relatively to said post slat and enablingthe angular bend in each slat to reinforce the rigidity of the angular bend in the other slat.

11. The method defined in claim 10, in which a plurality of the said post slats are strung onto at least one of said rail post slats, and a plurality of the said slats are bent in a manner to form said rail slat into a circuitous course bringing together the free ends of the rail slat.

12. The method defined in claim 11, together with the step of uniting the said free ends of the said rail slat in a manner to determine and maintain a fixed positional relationship of the said post slats.

13. The method of fabricating an open framework of longitudinally crossed flat faced metallic slats each capable of rigidly maintaining a bend when imparted thereto, which comprises the steps of, making a slit lengthwise in an upstanding fiat faced post slat, offsetting in broadside direction a component of the width of said post slat adjacent said slit so that said component forms a loop outstanding from the remaining flat face of said post slat, lacing a flat faced rail slat lengthwise through said loop in a direction crosswise the length of the post slat, and bending said rail and post slats simultaneously lengthwise of the latter and crosswise of the former within their common area of overlap, whereby the bending of each of the crossing slats reinforces the angular rigidity of the bend in the other of said crossing slats and also maintains said slats mutually interlocked with their lengths disposed in crossing relationship.

References Cited in the file of this patent UNITED STATES PATENTS 1,141,046 Dubus May 25, 1915 1,335,623 Uris Mar. 30, 1920 1,922,605 Spear Aug. 15, 1933 2,102,019 Miller Dec. 14, 1937 2,245,908 Drake June 17, 1941 2,427,393 Eckel Sept. 16, 1947 2,683,927 Maronek July 20, 1954 2,721,354 Anderberg Oct. 25, 1955