US3205633A - Floor or like tile - Google Patents

Description

Sept. 14, 1965 M. NusBAUM 3,205,633

FLOOR OR LIKE TILE Filed Jan. 3, 1963 L INVENTOR. Wlorhwlev/ NUS beu-LW) Sept. 14, 17965 M. NusBAuM FLOOR 0R LIKE TILE Filed Jan. 3, 1963 5 Sheets-Sheet 2 INVENTOR. movf MGC Nusbaww;

am @MJ Nttornry Sept. 14, 1965 M. NUsBAUM 3,205,633

FLOOR 0R LIKE TILE United States Patent O 3,205,633 FLOOR R LiKE TILE Mortimer Nusbaum, 940 Thorndale Drive, Akron 26, Ohio Filed Jan. 3, 1963, Ser. No. 249,197 The portion of the term of the patent subsequent to Mar. 26, 1980, has been disclaimed 6 Claims. (Cl. 52-591) This application is a continuation-in-part of copending U.S. patent application Serial No. 659,536, filed on May 16, 1957, now Patent No. 3,082,488, granted March 26, 1963.

This invention relates to tiles, and in particular relates to floor tiles.

Heretofore floor tiles, for example, have been provided in squares of thin material, usually of rubber, asphalt, vinyl plastic, or the like. Considerable skill was, however, required to apply such tiles to iioors, usually by means of tacky adhesive. Rough iioor surfaces and the diiiiculty of applying a uniform thickness of the adhesive materials frequently resulted in the finished iloor having unsightly wavy surfaces, exposed edges, and misaligned corners, whether the tiles were laid by skilled or unskilled persons. In some instances, tiles made of certain Inaterials could not be satisfactorily adhered to concrete basement floors, and it was impractical to nail or tack tiles of any kind to such concrete floors.

Itis a primary object of the present invention to provide interlocking floor tiles adapted to be installed on any kind of floor surface by relatively unskilled persons on a do-ityourself basis, without use adhesives or other means for attaching the same to the iioor.

Another object of the invention is to provide interlocking tiles of the character described, which may be iitted together on a floor in edge-to-edge relationship with no portions of the interlocking edge portions of the tiles unsupported to become damaged, as by shoe heel impressions or by furniture supports.

Another object of the invention is to provide improved tile units of the character described, which when interlocked will have the corners retained in accurately aligned relationship by the interlocking means.

Another object of the invention is to provide improved tiles of the character described which are of polygonal shape, such as square, including interlocking means which permits complemental interlocking of the side of any given tile with any side of any like tile, whereby the tiles are easy to install to have a wide range of patterns or ornamental design arrangements.

Another object of the invention is to provide a tile having an improved tongue and groove interlocking means by which a given tile, of square shape for example, may be easily interlocked with angularly disposed sides of two like tiles previously laid on a iloor.

Still another object of the invention is to provide interlocking tiles of the character described, by which tile units of relatively large size may be easily interlocked with corresponding interlocking means of like tiles of the same or smaller size.

Other objects and the invention will be manifest from the following brief description and the accompanying drawings.

Of the accompanying drawings:

FIGURE 1 is a top plan view of a self-locking tile embodying the features of the invention. q

FIGURE 2 is an edge View of FIGURE l.

FIGURE 3 is an exploded edge view, corresponding to FIGURE 2, illustrating a laminated structure thereof.

FIGURE 4 is a fragmentary top plan view on a reduced scale, illustrating a plurality of tiles as shown in FIG- URE 1, in interlocked position on a oor.

ICC

FIGURE 5 is an enlarged fragmentary cross-section taken substantially on the line 5-5 of FIGURE 4.

FIGURE 6 is a similar enlarged cross-section taken substantially on the line 6-6 of FIGURE 4.

FIGURE 7 is a further enlarged fragmentary crosssection, corresponding to FIGURE 5, and illustrating a modied form of the invention.

FIGURE S is a View corresponding to FIGURE 4, illustrating another modification of the invention.

FIGURE 9 is a view corresponding to FIGURE 1 and illustrating a further modification of the invention..

FIGURE 10 is a fragmentary perspective View, illustrating a modification suggested by FIGURESl to 8.

Referring particularly to FIGURES 1 and 2, there is illustrated a tile unit 10 comprising a relatively thin plate of generally square shape, providing four straight side edges of equal length. It is understood that the plate may be of other polygonal shapes, but the square plate is shown because it is the most commonly used shape for tile flooring. The plate 10 may be molded of solid material such as rubber, vinyl plastic, asphalt, wood, or other suitable material, having atop facing of good wearing quality. FIGURES 2 and 3, however, indicate the plate 10 as being of laminated structure including upper, bottom and intermediate layers 13, 14 and 15, respectively, cemented or otherwise bonded together, as shown in FIG- URE 2. The upper layer 13 may be of suitable colorful, ornamental, and long-wearing material such as rubber or vinyl plastic, and may be of square shape defined by straight side edges 11. The bottom layer may be of relatively hard material, such as wood ber in some instances, or a cushioning material, such as foam rubber, where desirable or necessary. The intermediate layer 15 immediately below top layer 13, may be of inexpensive material which is relatively rigid for purposes to be described. Bottom layer 14 is the same size and shape as the upper layer 13. The rigid nature of layer 15 reinforces theplate 10. y

Formed along each edge 11 of plate 10 may be a tongue and a groove 16 and 16a, respectively, of identical though oppositely disposed generally tapered shape, adapted to be complementally interlocked with like oppositely disposed tongues and grooves or recesses with a similar plate 10. When the plate 10 is of laminated structure, these tongues and grooves may be formed as by known stamping methods, in the intermediate layer 15, in which case the laminations would be bonded together as shown in FIGURES 1 and 2 by use of suitable jigs, fixtures or other means (not shown). The taper of each tongue is defined by a laterally outwardly presented straight edge 17, tapering from an angularly disposed edge 18 to a point 19 coincident with the corner formed by two adjacent side edges 11. The inner edge 18 of the tongue may extend extend at a substantially abrupt angle to the edge 11, an angle of 45 being shown, and thereby forming an obtuse angle with the longer edge 17. For purposes which will be understood later, corresponding tapered edges 17 of all of said tongues 16 extend in the same direction peripherally of the plate 10, and the grooves or recesses 16a are each oppositely complementally shaped to receive tongues 16 of a similar plate 10, without substantial clearance between the edges 17 and 18 of the tongues and corresponding inner angularly disposed faces 20 and 21 ofy the grooves, so that the long tapers of the grooves also all extend in the same direction peripherally of the plate 10, but opposite to that of the tapered tongues. The shorter edge portion of each groove is aligned with the shorter edge portion 18 of the nearest adjacent tongue 16 on the same side edge of the plate. In other words, the side edges of the plate are of predetermined lengths and the lengths of the tongues and grooves, as shown, are of a unit length which is one of equal increments of said predetermined lengthsof the side edges of the plate, said increment in this instance being one-half the unit length of each said edge of the plate, and in each instance adjacent apices of the narrow ends of next adjacent tongues and grooves coincide at each corner 1,9m' of the plate delined by adjacent cornering side edges'11 thereof. Thus, as the lengths of the tongues and grooves are equal, and are equal to one-half the unit length of the corresponding side edgeof the plate, each said side edge 11 is adapted to be selectively complementally interlocked with any side edges of any similar plate 10, or a portion thereof (onehalf in this instance). This feature has adistinct advantage in arranging a plurality of plates 10 with surface patterns, grains, or c onfigurationsin a variety of composite designs.

Use of the improved tile of FIGURES. l, 2 and 3 is best shown in FIGURES 4, 5 and 6, WhereinFIGURE 4 illustrates a plurality of tiles being laid on a tloor F, without adhesives or other means of attachment thereto. Assuming that rows A and B of tiles 10 have been laid on floor F in accordance with the usual practice of Ystarting a row A at the center of a room and working toward a side thereof, leach tile 10 is interlocked in tongue-in-groove relationship, as indicated by the zig-zag'dotted lines along f the plate edges 11, in FIGURE 4, and as clearly shown in FIGURES 5 and 6. In row C, for example, the tiles 10 are laid from left to right against like tiles of row B, previously laid in the same manner against tiles of row A. That is, one tile 1Q is shown being inserted cornerwise,

yas indicated by chain-dotted and full line. positions at the lower left-hand side of FIGURE 4, toward a position of interlocking tongue-in-groove engagement with right-angularly disposed sides 11 of two adjacent tiles 10, as shown at the right of row B. This cornerwise insertion o f the tile is greatly facilitated by the' fact that edge 18 of each tongue 16 converges with respect to the inner surface 21 of the` groove 16a of the next; adjacent side edge atthe respective corner 19. Because each tile 1,0 may have any side thereof interlocked, as described, with any side of any other similar tile, it is a simple matter to arrange groups of tiles with desired matching surface designs, or with the grain or patterns thereof in pleasing relationship. Moreover, the angular relationship of the edges 17 and .18 of each tongue, in interlocked relation to the corresponding surface portions 2 0 and 21, respectively, is effective to locate the corners 19 of each tilel exactly coincident with corners 19 of adjacent tiles mated therewith, and is further effective to retain matched tiles against relative movement longitudinally of the parallel matching edges 11 of the same.

Referring to FIGURES 5 and 6, the. bottom square layer 1.4 of each plate 1t)` may be slightly smaller than top square 13, substantially as shown in FIGURE 7, to assure perfect contact of the matching or mating edges 11, as described, and/ or perfect interlocking engagement of lthe mating tongues and grooves.

Referring now to FIGURE 7, there is shown an enlarged cross-section corresponding to FIGURE 5, illustrating tongue-in-groove engagement of two tiles 23, 23 of modified form'. Each tile 23 may comprise a plate 24 of molded rubber,` vinyl plastic, or the like, and a top layer V25 of carpeting suitably bonded thereto. The carpeting may be of known type wherein tufted Wool, or other stranded iber 26 is anchored or bonded in a cushioning layer 27 of soft resilient material, such as foam rubber. The layer 25 may also be of a thin veneer of tough but attractive rubber, vinyl plastic, or the like, but in any event the separate layer 25 makes possible the use of a relatively inexpensive base plate 24.

FIGURE 8 illustrates use of a modified form of tile 32 with a plurality of smaller tiles 30, 30 laid on a floor F as described in connection with FIGURE 4. The tile 32 may be of relatively large size, such as eighteen inches square, for. use with like tiles 30 of proportionately smaller size, sueh as nine inches square, for reasons to be described.

The large tile 32 may be made as shown in FIGURE 7 but with matched smaller segments 31, 31, say nine sixinch squares, of attractive material such as rubber or vinyl plastic, bonded to a larger square base plate 32. In place of the six inch segments 31 a singleeighteen-inch square of carpet ,materiaL such as the layer 25 of FIGURE 7, may be substituted.'

FIGURE 8 shows the base plate 32 provided with two spaced tapered tongues 34 and two spaced complementally shaped grooves 35, formed in each straight side edge 29, 29 thereof. As before, each tongue and each groove is of unit length which is one of equal increments of a unit length of each side, which in this case is one-fourth the length of each side edge. As before, also, each tongue 34 is longitudinally tapered, as dened by `a relatively long edge 36 at an acute angle to the respective side edge 29 of the plate or base 32 and a relatively shorter edge 37, at a more abrupt acute angle to edge 29, the edges 36 and 37 being at an obtuse angle to each other; The tongues and grooves extend around the base plate` in alternation, and, as in the case of thev FIGURE 1 structure, corresponding edges of the tongues taper toward the respective side edges in the same direction peripherally of the base plate.

The smallerv tiles 30 have tongues and grooves 34 and 35, respectively, of the same proportions and sizes as for the larger tile, and in either size of tile each corner has coincident therewith the terminal point of the wide end of tongues and grooves of adjacent side edges forming the respective said corner. Thus any tile 32 may be inserted cornerwise, as shown in FIGURE 8, toward interlocking tongue-in-groove engagement of two adjacent side edges thereof with correspondingly disposed edges formed by the pairs of adjacent smaller tiles 30. Ohviously, the large tile 32 may be similarly assembled on a floorF with like tiles of the same size. Cornerwise assembly of the tiles, in the manner shown,I in FIGURE 8, is facilitated by an outwardly converging relationship of a side 36 of a tongue 34 and a complemental surface portion of a groove 35, at each corner of the tile 32, or 30, as the case may be. v

FIGURE 9 illustrates a tile 40 which is like the tile shown in FIGURES v1 to 6, except that each side edge 41 has four triangular-shaped tongues 42 and four complementally shaped grooves 43, each of unit length which is one of equal increments of the unit length of each side edge 41. This structure functions precisely as previously described, except that the tilesr of one row may be Variously offset with respect to those of an adjacent row of tiles, to produce a greater variety of design arrangements.

FIGURE 10 illustrates a modication of the inven-` tion suggested by FIGURES l to 8 of the drawings, and wherein layers 13 and 15 have the tongue and groove shape and arrangement of FIGUREy 8, and a carpet layer 26 of FIGURE 7 is applied to layer 13,.

Thus has beenl provided improved tile structures adapted to be quickly and accurately applied on a floor surface by relatively unskilled persons. The various forms of the invention are particularly desirable to satisfy an apparent demand for tiles which may be applied on a do-it-yourself basis, withoutl the usual clutter and mesY siness incident to assembly of tiles requiring use of adhesives, for example.

In each form of the invention the tongue-in-groove relationship of tiles assembled on a floor locks the individual tile against relative movement in various directions laterally of the floor surface, and also locks each tile against upward movement with respect to an adjacent mating tile, thereby obviating difculty of persons tripping over exposed edges of tiles. Moreover, the tongue fully complementally engage in corresponding grooves, with no unsuppqrtedportions from corner to corner of the mating tiles, which is important also in eliminating any possibility of grime or dirt getting under the tiles from between mating edges thereof.

In actual use of the invention, where the tongue and groove arrangement of FIGURE 9, for example, is combined with the laminated structures of FIGURES l to 3, and when the tongues and grooves 42 and 43, respectively, are dened portions in a backing layer 32 of relatively rigid material corresponding to layer of FIGURES 2 and 3, the cushioning bottom layer 14 may be omitted. In such instances, when the tiles 31 are laid on a floor, each tile is rmly locked against the oor by the tongue 42 thereof being received in the grooves of the next adjacent or matching tile, and it is impossible to lift or otherwise remove any tile out of its locked position, except piece-by-piece in a manner converse to that in which the tiles are installed as previously described. That is, if it is desired to remove a particular tile, spaced at a distance from a given edge of the installed flooring, it is necessary to remove tiles, starting at that edge, and continue removing them until said particular tile is reached. Such removal of the tile, however, is accomplished in the same easy manner in which they are installed as described above in connection with FIGURES 4 and 8.

The relatively rigid layer 15, in fact, serves to retain the unitary tiles firmly interlocked, in edge-to-edge relationship, regardless of expansion and contraction of plastic, tufted carpet, or other relative more elastic layers supported or reinforced by the relatively rigid layer.

In further amplification of the description, it should be noted that in all forms of the invention shown and described there are the same number of tongues as recesses on each respective side edge of the tiles. Also, in each form shown, each corner of the tiles has edge portions of an adjacent tongue and a recess converging to the respective corner, from opposite sides of the side edge of the tile from which the respective corner tongue extends.

With particular reference to FIGURES 5, 6, 8 and 9, the adjacent edge portions of adjacent tongues and recesses, as for example 34 and 35 respectively of FIG- URE 8, of any corner of the tile are convergent to such corner, from opposite sides of the side edge 29 or 41 of the tile from which the respective corner tongue extends, and the angle between such side edge and the adjacent short edge portion of the respective recess includes an area to the corresponding corner having the full thickness of the tile, whether or not the cushioning layer 14 of FIGURES 5 and 6 is omitted. In this structure, moreover, the close proximity of the apices of the outer side portions of corner tongues 34 (FIGURE 8), and of the corresponding wide portions of the corner recesses 3S, to the respective corners, provide requisite optimum interlocking engagement at the corners of like tiles assembled tn mating corner relationship as shown in part in FIG- URE 8.

Referring particularly to FIGURES 4, 8 :and 9, it is to be noted that on any side of the respective tiles the straight edges dening longer sides of the tongues and recesses are in parallelism and the straight edges defining the shorter sides of the tongues and recesses are likewise in parallelism. It is also self-evident that the next adjacent unlike sides of tongues and recesses dening each aforesaid full thickness corner areas are always outwardly convergent or tapered. The FIGURE l tile incorporates these same relative conditions, includes the outwardly convergent, next adjacent unlike sides 18 and at each corner 19.

In further reference to the structure operatively exempliiied in FIGURES 4, 8 and lO, for example, the ratio of said shorter edge portions 18 and 21 to said longer edge portions 17 and 20 of the respective tongues 16 and recesses 16a being such that when any one side edge 11 of the plate is moved edgewi-se with respect to any side edge 11 of a like plate for any unit of inclined plane movement of the complementally engageable tongues and recesses 16 and 16a 'along the longer said side edge portions 17 and 21 thereof the resultant relative movement of the two right-angularly disposed directions in the same ratio that said widest portions of the tongues are to said longer edge portions thereof. With particular reference to FIGURE 8, for example, it is readily apparent that in laying tiles on a oor in successive rows, ordinarily each successive tile may be inserted edgewise on the iioor toward mating cornering relationship with two other cornering tiles, without diiculty (see full-line positions in FIGURE 8). The taper which the long edge portion 36 of each corner tongue 34 makes with the short edge portion 37 of the corresponding corner recess provides such a substantial amount of clearance that the tile being positioned on a floor may be pushed into place more or less haphazardly until it eventually comes into self-centering mating tongue and groove relationship. That is, ordinarily the tiles may be more or less thrown into mating relationship due to the angular relationship and proportions of the edge portions of the tongues and recesses.

Another very important feature of the invention comes into play when the last tile in each row of tile is being positioned next to a wall. In this case, the principle of the inclined plane is utilized to minimize the amount of space required for insertion of each successive tile. That is, `assuming that in FIGURE 8 the wall of the room extends substantially along the line A-A, the tile being inserted may be tilted at a slight angle to the iloor to permit insertion Iof the forward tongues 34 of the tile within the corresponding grooves of the ajacent tile (at the top of FIGURE 8), while thc straight side at the left of the tile being inserted is spaced from the corresponding straight side of the adjacent tile a distance approximating the maximum width of Ithe tongues (at the left of FIGURE 8), and otherwise substantially as indicated in chain-dotted lines in FIGURE 8. In this chain-dotted line position the long sides of the tongues are engaged with the corresponding long sides of the mating grooves before the corresponding mating straight edges engage, but the spacing between these mating edges, indicated at y, is relatively slight and, therefore, negligible for reasons which will be explained later. It will be apparent that while the tile being inserted is in the chain-dotted line position it may be dropped into llat engagement with the floor surface without interference with the wall A-A, and it then may be slid flatwise to the left, into full interlocking position with the two adjacent angularly disposed mating edges of previously laid tiles. The letter x indicates the spacing between the adjacent edges at the left before full interlocking insertion is accomplished.

Accordingly, it will be noted that on the principle of the inclined plane, while the fully inserted tile is moved a distance x to the left it is moved forwardly only a very slight distance y. This explains why the unitary tiles may be inserted at the side of a room where the spacing is substantially equal `to the width of the tile plus the width of one tongue. In the commercial form of the invention, the ratio of x to y is approximately 8 to 1. In other words, where x--I inch, y=%,2 inch or less. In actual practice a slight clearance i-s allowed between the edges of the triangular tongues and the mating edges of the corresponding grooves, so that the forward edge of the tile being inserted will actually be in engagement with the corresponding edge of the mating tile in the relative position shown in chain-dotted lines in FIGURE 8.

Of course, the floor space being covered will as often as not require portions of outside squares nearest a wall to be cut to lit. The partial squares, however, may be started in lat a slight angle to the wall and then otherwise slid ilatwise into interlocking position, as described above in connection with FIGURE 8, to have cut edge against wall A-A. y

Other modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims.

What is claimed is:

1. A oor or like tile comprising: a relatively thin, unitary plate having an upper portion of rectangular shape defined by straight side edges; a lower portion of said plate below said rectangular portion being formed with reference to said side edges and having alternate tongues and recesses extending outwardly and inwardly, respectively, of said side edges, peripherally around the plate; each said side edge of the plate having the same number of tongues as recesses; said tongues being substantially uniformly thin and each tongue being defined by angularly opposed edge portions tapering substantially in divergent straight lines from an apex thereof, and each line being disposed at an acute angle -to the respective side edge of the plate and the recesses being correspondingly defined; one of said opposed edge portions of each tongue and recess being longer than the other, the longer and shorter edge portions of each recess being aligned continuations of the longer and shorter edge portions of the tongues, respectively; and corresponding edge portions of like tongues of the respective said side edges being so tapered from the apices of the respective tongues in the same general direction peripherally around the plate; said corresponding edge portions of any side edge of the plate thereby being adapted for inclined-plane sliding engagement with oppositely disposed said corre sponding edge portions of the side edge of a like tongued and recessed plate toward edge-to-edge relationship of the like plates; the lengths o'f said tongues :and recesses along said side edges being proportioned with reference to predetermined lengths of the respective `side edges that the short edge portions of a tongue and the aligned continuation of -the recess nearest each corner apex termi- S nate in spaced relation-ship to the respective corner Iapex; said like plates in said edge-to-edge relationhsip thereby being adapted to have the opposite tongues and recesses thereof c-omplementally interlocked with corresponding tongues and recesses thereof when the like plates are laid iiatwise on a supporting surface.

2. A floor or like tile as in claim 1, wherein said upper and lower plate portions are integrally formed of relatively rigid synthetic resin material.

3. A Hoor or like tile as in claim 1,` wherein said upper portion of the plate has alxed thereto a covering of flooring-like decorative material.

4. A floor or like tile as in claim 1, wherein said upper portion of the plate is of square shape.

5. A iioor or like tile as in claim 1, the longer edge portions of a tongue and a recess terminating at each corner apex of said plate and having adjacent edge portions thereof convergent to 'and intersecting at the respective corner apex from opposite directions inwardly and outwardly of the edges of the plate.

6. A iioor or like tile as in claim 5, wherein at least the lower portion of said plate is of relatively rigid material, and the tongues being relatively rigid extensions of said lower portion.

References Cited by the Examiner UNITED STATES PATENTS 1,420,810 6/2'2 Bean 52-594 1,437,304 11/22 Healy 52-591 1,895,801 1/33 Keller 52-591 2,175,698 10/39 Netz 52-589 X 2,605,204 7/52 Benedict 94-3 X 2,899,398 8/59 Piiaumer 260-23 2,925,831 2/60 Welty et al. 52-309 X RICHARD W. COOKE, JR., Primary Examiner.

JACOB L. NACKENOFF, Examiner.

Claims (1)

1. A FLOOR OR LIKE TILE COMPRISING: A RELATIVELY THIN, UNITARY PLATE HAVING AN UPPER PORTION OF RECTANGULAR SHAPE DEFINED BY STRAIGHT SIDE EDGES; A LOWER PORTION OF SAID PLATE BELOW SAID RECTANGULAR PORTION BEING FORMED WITH REFERENCE TO SAID SIDE EDGES AND HAVING ALTERNATE TONGUES AND RECESSES EXTENDING OUTWARDLY AND INWARDLY, RESPECTIVELY, OF SAID SIDE EDGES, PERIPHERALLY AROUND THE PLATE; EACH SAID SIDE EDGE OF THE PLATE HAVING THE SAME NUMBER OF TONGUES AS RECESSES; SAID TONGUES BEING SUBSTANTIALLY UNIFORMLY THIN AND EACH TONGUE BEING DEFINED BY ANGULARLY OPPOSED EDGE PORTIONS TAPERING SUBSTANTIALLY IN DIVERGENT STRAIGHT LINES FROM AN APEX THEREOF, AND EACH LINE BEING DISPOSED AT AN ACUTE ANGLE TO THE RESPECTIVE SIDE EDGE OF THE PLATE AND THE RECESSES BEING CORRESPONDINGLY DEFINED; ONE OF SAID OPPOSED EDGE PORTIONS OF EACH TONGUE AND RECESS BEING LONGER THAN THE OTHER, THE LONGER AND SHORTER EDGE PORTIONS OF EACH RECESS BEING ALIGNED CONTINUATIONS OF THE LONGER AND SHORTER EDGE PORTIONS OF THE TONGUES, RESPECTIVELY; AND CORRESPONDING EDGE PORTIONS OF LIKE TONGUES, OF THE RESPECTIVE SAID SIDE EDGES BEING SO TAPERED FROM THE APICES OF THE RESPECTIVE TONGUES IN THE SAME GENERAL DIRECTION PERIPHERALLY AROUND THE PLATE; SAID CORRESPONDING EDGE PORTIONS OF ANY SIDE EDGE OF THE PLATE THEREBY BEING ADAPTED FOR INCLINED-PLANE

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