US2805859A - Metal springobard - Google Patents

Description

Sept'. 10, 1957 R. c. RUDE 2,805,859

METAL SPRINGBOARD Filed Oct. 26, 1953 2 Sheets-Sheet l INVENTOR. RAYMOND C. RUDE ATTORNEY Sept. 10, 1957 R. c. RUDE METAL.l SPRINGBOARD 2 Sheets-Sheet 2 Filed Oct. 26, 1953 uw ,B mf m1 J gm IN V EN TOR. RA YMOND C. RUDE Lm@ m @mx/ vm, www www, A

A TTORA/ E y JM @E Tm J@ gm Patented Sept. 10, 1957 Hice NIETAL SPRINGBOARD Raymond C. Rude, Arcadia, Calif.

Application October 26, 1953, Serial No. 388,316

6 Claims. (Cl. 272-66) This invention relates to improvements in spring boards and particularly to metal springboards for private and public swimming pools.

The average wooden springboard has `a maximum life of two years with normal maintenance attention, but may be useable for only six months if neglected or used in a very arid region.

The preferred board of my invention is made from aluminium alloy or similar metal stock and therefore presents no maintenance problems. Deection tests indicate a minimum life of ten years for a board formed from 24 ST aluminum alloy material. Similar longevity can be expected of boards made from suitable allied `alloys like 61 ST, 75 STor 75 ST-6.

A conventional wooden board must be from l2 feet to 16 feet long to provide competent divers with the desired deflection and resilience for good diving. Boards of this length are very dicult to accommodate in the relatively small area usually `allocated for private home pools. A ten foot board made according to my invention provides the diving qualities of a sixteen foot board of conventional design, and is ltherefore better adapted to home pool use.

T he preferred form of the invention is a metal springboard which is Iadapted to be supported by conventional -anchoring means at `one end. Between its ends the board is supported by fulcrum means in the usual manner. The board comprises a top plate having a at upper surface extending from end .to end of the board. A plurality of longitudinally extending spaced parallel ribs are formed integrally with the top plate on the under side of the plate.

Preferably the top surface of the board `is made slipprocf by covering its surface, which may be painted, with transverse closely spaced, narrow abrasive strips. Such strips are commercially available with adhesive backing,

or may be applied with a suitable binding agent. An 7 alternate method of slip-proofing the board -is to paint its upper surface with a sand-lled paint.

A board of the above described configuration may be extruded by means of suitable dies, or may be milled from fiat stock in a milling machine capable of handling the average 18" board width. In accordance with preferred practice the board is fabricated from a single piece of metal.

An alternate means of fabrication is to form substantially similar ribbed portions which are assembled to form a top plate comprising two sections which abut and are held together along a line parallel to the longitudinal center line of the board, extending from end to end. It is important that the board be free of any transverse joints,

The ribbed configuration achieved by any of the above methods has advantages not found in previous boards.

The vertical thickness of selected ribs can be reduced to increase the deliection of the board. This makes possible a wide range of pre-selected deflections. Any chosen degree of deiiection will remain substantially constant Ithroughout the life of the board because of its design and material.

A very high safety factor is inherent in such a metal board vbecause the board will bend almost to the water before faulting, while the conventional board heretofore had an average safety factor of only 2.

`The strength of the ribbed board makes possible a slimmer, clean-lined board of more than usual esthetic appeal.

These and other advantages of the invention will be apparent from the following detailed description and drawing, in which:

Fig. 1 is `an elevation `of a .typical installation of a board made according to the invention;

Fig. 2 is a fragmentary bottom plan view ofthe board of Fig. l;

Fig. 3 is a sectional elevation `taken along the line 3-'3 of Fig. l;

Fig. 4 is a fragmentary longitudinal section of a modiiied form of the board of Fig. 1;

Fig. 5 is an elevati-on partly in section of a further modification of the board of Fig. l;

Fig. 6 is a transverse section taken along line 6-6 of Fig. 5;

Fig. 7 is a plan view of a board with the preferred form of non-slip surfacing;

Fig. 8 is a side elevation of the preferred embodiment of the invention;

F Fig. 9 is a sectional elevation taken along line 8 8 of Fig. l0 is a fragmentary bottom plan view of the board of Fig. 8; and

Fig. 1l `is a sectional elevation of a board in accordance with .the invention fabricated from two formed longitudinal sections.

Fig. l is an elevation `of `a metal springboard 20 .that is formed from a single plate of lightweight resilient metal such as 24 ST aluminum alloy. The board as illustrated is mounted at the edge of a pool 21 by means of au anchoring support 22 and a fulcrum frame 23 which has a conventional movable transverse fulcrum bar 24. Two holes 25, 26 through the end ofthe board provide means for fastening the board to the anchoring support 22. The invention is not concerned With refinements of anchor and fulcrum construction.

The bottom of the solid plate has wide arching slots therein so that the board has a Itop plate 27 of varying vertical .thickness strengthened by integral ribs that `are parallel and extend longitudinally along the bottom of the plate. There are four ribs 28, 29, 30, 31 be- '.tween an anchored end 32 of the boa-rd and a flat fulcrum surface 33 and four forward ribs 34, 35, 36, 37 extending from the fulcrum surface to the outer unsupported end 38.

As shown in the dotted lines -in Fig. 1, .the top plate has a bottom surface 39, 39' between the ribs that arches from the -anchored end 32 of the board .to the fulcrum surface 33 which extends on either side of the fulcrum bar, and then diminishes in vertical thickness from the 3l i fulcrumsurfacetothe Aouter end 38 of lthe board. The fulcrum surface is Yparallel 'to Lthe top Vsurface of lthe 4plate 27 and affords a continuous bearing area for the movable fulcrum bar 24.

The forward ribs 34, 35, 36, 37 of the board in Fig. 1 are formed on a uniform taper beginning at the fulcrum surface and continuing to the outer end of the board. The taper of the ribs is less than the vtaper of Ethe bottom surface 39 of the top plate. The rear ribs are uniform and have bottom surfaces substantially parallel to the upper surface of the top plate. All ofthe ribs are equjally spaced -and relativelygthin compared fto the board width (see Figs. 2fand3). Y Y

Y:In igflt the-board-oflFigs Cle-to' Jhas beenmodifedto provide greater per-unit length liiex'ibility. The vvertical thickness Aof the -inner-'pair'of-rear ri-bs-29, fhas been diminished -by Van Jarching Acut 40'the width vofeach rib and extending 'from 2the anchored end vofthe board to the fulcrum surface. The arch of the cut is greatest Vat the midpoint between't-he anchored Vend-and lthefulcrum surface. y'The reduction 4in strength atV this 4poin-t isv sufticient to give the modified board -mar-kedly different performance when compared Lwith the-boardcof Fig. 1.

If Astill more iiexibility is desired, as may betrue if lighter `divers use the board, or where extremely short boards are required, the thinning cut is milled in "both inner 29, 30 and outer rlibs 28 31 as illustrated in Figs. Sand-'6.

Conventional non-slip surfaces such Aas Acoco matting are ybulky and :therefore not in harmony vwith the trim lines of the metal board. iFig. 7 illustrates theg'use of a plurality fof .narrow Aalnasivelstrips 41 to provide a safe surface for divers using the board. VThe strips are fixed Vtransversely to ,thepaintedftop surface of thevboard along its entire length. Each strip is separated from the adjoining stripsby a small transverse interval-42 to 'increase the gripping characteristics of the surface. The `non-slip qualities oftheabrasive surface of :the strips 41 is not in itself suiiicient guarantee of safe footing. lHowever, when the VStripsare appliedacross the width of the board with a relatively narrow interval between the strips, the intervals provide sutiicient additional friction to Jinsure safe footing.

The preferred -form ofthe invention is best illustrated in Figs. 8, 9 and 10. Board 50 shown in these figures is made .from extruded :ribbed stock, which has a top plate 51 of uniform thickness from end to end. Two longitudinal vouter ribs 5,2, 53 form the sides of the board. Adjacent each outer rib and parallel to it arethree inner ribs ,-5.4 of equal vertical thickness. VThe ribs'are placed nearer the outer edge ofithe board than they are to Athe center of the board in order to eliminate .any tendency toward canting at ,theunsupportedencl 55 of the board.

,All ribs taper vuniformly 'from just forward of the fulcrum area 56 to a point adiacentthe Aouterend of the board. At theend 5 of -the board the rib portion is cut away `and Vthe top plate 5 1 is bent downwardly in an are to form a smooth lip 5.7,.

The board .is supported vvin the same manner as the board of Fig. liexcept that the Vbottom surfaces of the ribsfform the fulcrum-surface oftheboard.

The flexibility of the extrudedboard may be increased by reducing the vertical thickness of `one or more of -the ribs yinthe area -betweengtheanchored end 58 and the fulcrum area 56 ina manner similar to zthat shown in Figs. 4.and5.

VThe ,board of the invention Arnay-'be made of more than one piece, although unitary ,'cQustrllQtion is preferred for reasonsof costaud durability. LA two piece :board of the extrudedtype is shown in Fig. ll. f

Two extruded sections 60, 60A having opposite, but similar lconfigur ation yare held ,together as v,by rivets 61 shownin figli. Eachsection has apair of parallel longitudinal outer ribs .62, 63 andthree innerrlongitudinal ribs 64-Which are,parallel tothe outer ribs. The inner ribs 6,4.are,spacedequallylfrom Cash ,ether endareasym- 'Y 2,805,859 u j t. -Y

4 metrically located with respect to the longitudinal center Yline of-their respective extruded section.

The sections are assembled to form a board 65 so that the inner rib cluster 66 of each section is near the outer side 62 of the assembled board. It is important to assemble the component sections of the board on a longitudinal line to obviate the stresses that would bear on the fastening members if the sections abutted transversely. The fastening members of a transverse joint would be subject to the flexure load of the bending board. Since the fastening members of a longitudinally joined board are free from shear stress the boardvwill have a materially Y longer life. After the extruded sections 60, 60A are assembled, the board 65 is machined to the desired configuration in the mannerfdeseribed for the embodiment of Figs. 8, 9 and l0.

Both of these latter Vembodiments may be covered with a number of abrasive strips: 67 to provide a non-slip upper surface.

The embodiment of Fig. is prefer-red -because.of its adaptability to mass .production methods, but any board manufactured according to the invention will be superior to conventional wooden or metal boards in flexibility for a given length, durability, maintenance, cost, and safety.

I claim:

1l.,A metal diving .board having an anchoring end, a flexingend Landa fulcrum ysection spaced a substantial distance from both ends, -the'board.comprisingr'a continuous fiat-.plate zforming :attop and :bottom surface of the board, a :plurality of longitudinally extending parallel ribs rformed :integrally with the plate on either side o'f the longitudinal centerline of the boardandon the underside ,of `the plate :to project normally from :the bottom surface :and spaceditransversely so lthat amajority of Ythe Vplurality oftribstoneither side of vtheilongitudinal.centerline ,of :the :board are fat Va, lesser distance Vfrom :the Asides 0f the z board than fromV the centerline, .the section. modulus of the fulcrum `section being substantially the same as that of the anchoring end and the vertical thickness ofat least@ rJaJ'Qrity of the;ribs on each .sideof the centerline diminishing continuously :from the .outboard end of :the flllCrllmSCtiQn to the exing endof the board.

A2. A diving :board vin accordance ,with claim 1 `comprised of two substantially identical longitudinal halves fastened together `alongthe longitudinal centerline of the board.

3. A metal diving Yboa-rd yhavingan vanchoring end, a exing end Yand .a fulcrum section spaced .a substantial distance from Vbothends, the board consisting of a continuous flat plate forming a top and vbottom surface of the board, Va plurality of longitudinally extending spaced parallel ribs formed integrally with 4the plate on either side o f the longitudinal centerline -of Vthe board anden the underside ofthe plate -to Aproject norm-ally from the bottom surface, the lsection modulus `of the `fulcrum section being substantially the same as that at the anchoring end and the verticalthickness ofat'least a majority ofthe ribs on each side of the centerline diminishing continuously from the outboard'end `of the-fulcrum sectionto the flexing end of the board.

4. A metal diving board having van anchoring end, a iiexingend and -a fulcrum jsection spaced a substantial distance from both ends, theboard comprising of a continuous fiat plate forming a top and bottomsnrface of the board, applurality Vof longitudinally extending spaced parallel ribs Vformed integrally with the plate on either side of the longitudinal centerline of vthe'boardand on the underside of the board to project normally from the bottom surface, the section modulus .of the fulcrum section being substantiallythe Ysame Aas that Vof the anchoring end and the vertical thickness of all of the -ribs ydiminishing continuously from the outboard end of the fulcrum section t0 the .exingend Qf-,thebrd 5. .A diving `board in accordance with Vclaim A4 comprised of two substantially identical longitudinal halvesV fastened together along the longitudinal centerline of the board.

6. A metal diving board having an anchoring end, a exing end and a fulerurn section spaced a substantial distance from both ends, the board comprising a plate forming a top and bottom surface of the board, a plurality of longitudinally extending spaced parallel ribs formed integrally with the plate on either side of the longitudinal centerline of the board and on the underside of the board to project normally from the bottom surface substantially from end to end of the board, the plate being of increased thickness in the region of the anchoring end and the fulcrurn section so as to merge with the lower edges of the ribs in these regions and to give the board a relatively high section modulus of substantial equality in these regions, the vertical thickness of all of the ribs diminishing continuously from the outboard end of the fulcrum section to the flexing end of the board.

References Cited in the tile of this patent UNITED STATES PATENTS 1,574,563 Duff Feb, 23, 1926 1,710,350 Dewoitine Apr. 23, 1929 2,193,067 Hoppes Mar. 12, 1940 2,245,497 Potchen June 10, 1941 2,649,304 Ulanovsky Aug, 18, 1953

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