US1929081A - Seesaw - Google Patents

Description

T. SERPICO Oct. 3, 1933.

SEESAW Filed June 25, 1932 2 Sheets-Sheet 1 III 1 E: x Q

7 I RNEY- Patented o'cha iess l I 9 031" UNITED STATES j PATENT; OFFICE" SEESAW Thomas Serpico, Brooklyn, Y. 7 Application June 25, 1932. Serial No; 6220,6335

6 Claims. iol. 2021-249 l ,This inventionrelates more particularly to that pears most clearlyin Figure 3, to provide nar-' type of seesaw device which has'a traveling moverower front and rear end extensions, with shoulment imparted "thereto 'by the seesawing opdel's at the opposite sides of these respective eration, although some of the featuresof imextensions, all corners-fbein g rounded. The provement ma'y also be embodied in other kinds" fl'ame as, a whole further includes 'a transverselygfi .ot seesawdevices. f g arl'anged r iser or upright 2whic h rises from-the 1 Among the obje ts of the inventi on i s tozpro- -frame plate 1 midway of its length. This upright vide a traveling seesaw device which will afford is in general of inverted U-shape to provide a .a maximum of pleasureand' amusement to the bench, as appearsmostclearly invI'ji'gure 4. The riders, whichwill be convenient and easy to oplower Tends, of the legs or" standardsfoi this erate, and which will operate .eflectively-andre- U-shaped bench are rigidly and 'firmly secured vto r liably I l. theirame plate 1' adjacent to its edges by means fotherobject is to'attain simplicity of conof, for example; screws or bolts (not-shown). struction together with economy and convenience This upright 2 is-indicated in the drawings'as 1 in manufacture as well as adequatestreng'th and made from wood but it could be of metal, sub-: durability. Other objects and advantages of the stantially of-theshape'shown or of a more or less invention will hereinafter appear 1 v differ nt s p 7 1 In carrying out the invention there is pro: The entire deviceis supported for traveling .vided an improved arrangement of supporting movement upon four rubber-tired disc wheelsB,

' wheels by means of which the device is propelled 4, 5, and 6, comprising the two larger left and andsteered, improved power-transmittingoperaright side wheels 3- and 4, andthetwo smaller tionmechanism through which traction is affectfront and rear wheels 5 and 6. The left hand 3 n i p d S g ear, an adju t side wheel 3isa traction wheel, fixed o -the end sn nzh c u e n an i pr l' e'; portion'of a driveshaft Tjournaled in apair of so leeat ba c'o struet i o p ra i w bearings a; 8 secur'edon the lower side of the Y adjustable n holdsh invention valso ipl'atform formed by the frame plate 1. The other ther includes variousjeatures of constructionand t hand sidewheel 4,1 merely asupporting FombiPations Q Part5, as w appear rfrom the "wheel; being an idler loosely rotatively'mounted 30 followmsdesqnptwn- Y on theother endlportion'of the drive shaft 7.8

' l 7 One embodiment of the invention, shown in the The drive shaft 7 is located midway of t length accompanying drawings,v will now Particularly of the frame platform 1 in-verticalalignmnt idescribed and thereafter h invention :Will with theup'right 2,.with the side wheels 3 and 4 I pointed out in claims, reference now being had beyond the edges of t platform i t f 9 drawings. m wmq w smaller ,front and rear-wheels-4 and 5Iare entirely. fi l 1s a Plan a travelmg s w below 'the' level of this platformat its front and device in which the invention is embodied; v

Figure 2 is a vertical longitudinal section of "such device taken substantially-on the zig-zag rear ends;. .7 e V The front wheel 5 isa steering wheel, while the rear wheel6 is a caster wheel. The steering wheel 5 has an axle Q'carIriedby a steering fork 10 This steerin'g'fork hasits yerticalitem at the 'top thereof swiveled in abearing'through the front-end of the platform frame plate l The upperend of this stem has a disc 11' fixed thereon i -Lin the drawings as an emliodiment of theinabove theYfmmg plate'ril' 3 v l i ventijon is indicatedas beingycbnstructed largely 3 h pf i g of metal; but with some parts 'of wood, although 'm m Its i 3. 3 we? the relative proportionsof these materials may of control screw The'steenng k}? m yb 7 Vibe afi 'd1 s desi diun any, particular turned for steer ngby means lot thed sc 11, as cilmstan'ces. However, met-al parts in such ade- Win-hereinafter ,appealr'. IThe caster wltefilis-hat vice arev inexpensive and commonly more durable an axle 13 Earned by 3 15 fork o a k tha'nwood. V l v 1 V 1 v frame 14' the caster stem of which passes through The illustrated device has a main frame plate and is jou d. in a bea fl fgl h r arend 1 of suitably strongand'thick metal such as steel; the frame pla l h s e ner the ast rf rk This frame Plate issymmet iww sh ped; as '81 4 is a d n its l i l aw 15 a line 2 -2 of'liigure l v Ffigure3 is" a horizontal] section on the: line 3-3 ofFlgure 2; and 1 3 Figure 4 is a rear end'elev tion as viewed from [theleft in theprecedingfigurs} i,

The particular traveling seesaw device shown the frame plate 1 and held in place by a control screw 16.

An elongated seesaw member 17 extends longitudinally or fore and aft in elevated position above the frame plate 1 beyond which it projects at both ends and is fulcrumed at the middle of its length on the top of the cross bar which joins together the legs or standards of the bench or upright 2. seesaw member may be desirably formedof a-suitably strongspring steel plate, as indicated in the drawings. At the middle of its length the seesaw plate 1'7 is of a width substantially equal to the length of the fulcrum bench 2,

. thereby providing sufficient stiffness and strength. This seesaw plate more or less gradually decreases in width towards its ends, terminating insuitably narrow seat-forming end portions having parallel lateral edges. For effectively serving its practical purpose as well as for ornamental effect this seesaw plate may have substantially the contour shown in Figurel. 'This seesaw plate will be reder the weight of theriders.

'siliently yieldablc-to a desirable slight extent un- The-seesawmemberl'l is fuicrumed to rock on 'the upright 2 bymeans-of a stiff transverse rod i or shaft 18 which is shown as firmly secured to the plate l'lagainst its-lower side by a pair of 5 screws 19, 19. "This shaft 18' rests and may rockjin anarcuate groovealong the top of the upright 2 which is beveled to incline downward away from this groove to provide'clearance for theseesawmember 1''? in its rocking movement.

Theseesaw member 1'7 is furtherpivoted and held in place by means a of reduced journal ends '20, 20 on the shaftl8'which are pivoted in bearings21,'21 secured 'by screws 22, 22 to thej up- ,1 right 2.

'The operating 'mecham'sm comprises -power transmitting connections for imparting rotation -'to the traction wheel 3 from "the rockingseesaw 1 member 17.; -In the embodiment of the'invention -illustrated'in the drawings, this operating mechanism includ'es-gearing which is-shown as multiplying gearing, although so far :as the invention is concerned thegear ratio mightbe'differentand could, for example, be :reducing gearing; In the constructionshmfinthe drawings,. a smallflrs't spur gear23 is fixed on the drive shaft '7 between its bearings 8 .and .atithe 1 center of *the platform =.plate 1 above which this :gear 'slightlyyprojects through an :opening provided -for the purpose.

' second and larger spur gear .24, shown .as 'twice thediameter of the;smaller gear '23, has

intermeshingdrivingengagementwiththejlatter.

' "This driving .gear:24. jSLfiXEd upoma' crank shaft 25 which is located directlyabove the .drive shaft 71. The crank shaft passes through and isjour- .sothahtherejs therebya mutual bracing effect,

iparticularlyfof the upright 2, longitudinally of .the platform-1. I

pair o'f.similarlcrankarms 27 and 28, of

i equal-length, are fixedrrespectively upon .the op .;posite. projecting ends of V the crank shaft 25;

the construction shown ,eitherone or the other of these crank. arms. may be operatively' utilized in the driving connection while the other crank arm. necessarily rotates idly, "as will presently apwhich are locked together.

pear. As illustrated in the drawings, the adjustments are such that the left hand crank arm 27 is utilized as an operating crank while the right hand crank arm 28 is an idler.

The left hand crank arm 27 is connected to the seesaw plate member 17 to be operated thereby by means of a two-part longitudinally telescopic connecting rod. This connecting rod comprises a lower part 29 in the form of a sleeve and. an upper rod part 30 telescoped into the sleeve and locked in longitudinally adjusted condition therein by means of a set screw 31 in the sleeve part 29 to clamp the rod apart 30. The lower end of the sleeve part 29 is pivoted on the wrist pin of the crank 27 on which it is held in place by an end screw 32 together with a washer 33. The upper end of the rodpart 30 is pivotally connected to the seesaw plate member 17 in rearwardly spaced relation from its fulcrum rod 18 by means of a pivot pin 34 carried'by a depending bifurcated bracket 35 secured by bolts36, '36 to the screw member. I v

n The pivot pin 34 is shown as spaced from the fulcrum shaft 1 8 a distance which is substantially three times. as great as the effective length 'of the crank 27. It is clear that this operatively connected connecting rod may be adjustably lengthened or shortened thereby adjusting the position of the seesaw member 17 in its rocking movement. It is of course to be understood from the'drawings that the clamping screw 31 is in tightened condition so that thereby the two telescopic parts 29- and 30 of the connecting rod are securely locked together to operate as a unit and by reason of which thecrank 2'7'is operatively' connected to the seesaw memberl'l.

. It is'to be understood from the drawings that the other or right hand crank arm 28'has an idling pivotal connection to the seesaw member 17 by means of a longitudinally telescopic connecting rod which is of the same construction as that just described for the left hand crank arm 2'7. This connecting rod for the right hand crank 28 similarly comprises a lower sleeve part3? in which an upper rod part 38 freely telescopes, the sleeve part 3'7 being provided with a set screw '39 which in this instance'is left in looseer unclamping relation with the telscoping' rod part 38 so that. thereby the latter is free to slide in the sleeve 37. I I I The lower end of the'sleeve part'B'lis pivoted on the wrist pin of the crank 28 and held thereon by a screw 40 and washer 41. The upper end'of the rod part 38 is pivotallyconnected to the seesaw member 17 in forwardly spaced relation from its fulcrum rod 18 byjmeans of a pivot pin 42 carried by I a depending bifurcated bracket 43 secured bybolts' .44, 44 to the seesaw member.

The spacing of the pivot pin 42 from the fulcrum rod 18 issubstantially-equal to three times the clearly indicated in Figure 2, in whichthis connectingrod is shown as elongated or drawn out substantiallyto the greatest'extent, in which it is of considerably greater length than the operat- ,ing connecting rod, the two parts 29mm 30 of in the cycle of movement, substantially opposite 'to' that shown, the freely telescopically, sliding parts 37 and 38'of the idling connecting rod will be pushed together substantially'to their greatest extentso that this connecting rod will thus be In another position its parts 29 and 30.locked.together.w

shorter than the operating connectingmod with t The right hand connectingfrod may-be used as the driver instead of the left hand connectingrod, merely by loosening the locking ;screw 31- of the latter and tighteningthe locking-screw39 of the former-with its parts 37 and 38in operatively correctadjustedposition. 'Withboth oi the looking screws 31 and39 set tight the entire mechanism vwould be locked; against operation,- ,as. is evident fromFigure 2. The above described operating mechanism not only provides for substitute operation by meansv of either one or the other of the cranks27uor 28 but'also desirably results in a balanced appearanceof the entire seesaw device as a whole.

It will now-be clearly evident that one of the connectionsmay be made soas atall times to -be rigid or non-telescopi with the other. connection then made tobej at all times freely telescopically slidable as an idler. For example, with the left hand-connecting rod for the crank 27- made all in one piece or otherwise permanently non-slidable, .the right han'd connecting -.rod, would =-be made to .be permanently freely, telescopically slidable, the clamp screw 39-.then being omitted. In such-casethe operation would be the same as abovedescribed and indicated tinthe drawings, ire with theleft hand locking screw 31 tightened and theright-hand locking screw. 39 loosened;

.JThe steering is done by, the vI rear seat rider,

since. .-rider, faces forward. In carrying out this featurethe steering gear connections include a pair of .fro-operating;oppositelymovable. flexible connecting members eirtendingfore and aft. A pairof'steering chains 15, 15 have their adjacent front ends connected respectively to eyes;46, 46

.onthe di sc ll of the steering fork 10 atequally distant oppositesides laterally from the pivotal ,axiso; the steering fork and its disc 11, which thus becomes atWo-arrned steering lever. These chains extend rearwardly alongside of each other in spaced relation and have their Ie'ar'endsrespectively connected to lateral eyes 47, 4'1 carried onthe upper side of and equidistantly i-spaced from the pivotal axis of a steering disc 48', which i J ;is immediately above the rear of the wider central .portion of the frame platel, and whichforrns a two -armedoperating lever forcausingthe chains 45 to be moved concomitantly in opposite direc ,tions for thereby pivot'ally thesteering Lwheel 10 in its steering operation."

a Itfwillbe notedthat thesteeringjfork 10 will ';be' rockedfin the same'rdirection asjthe s'teering ,disc 48. andjto a', somewhat greater" .extentrby reason of the slightly longer lever 'armsion the Y'steerin'g disc 48 thanionthe steering fork disc ill, thereby requiring ,a'jsmall'amount of slaclr in the connecting operating I hains 45, 45; Two pairs of'guideeyes 19, 49. are desirably provided f'on the platform plate lfor these chains, one such pair being located in forward adjacency tojthe steering disc'48 and the other pair beinginter- ,mediatelydocated relatively to the steering fork cs 'fsho'wh as mounted upon the respective ends of a is'c 11.. These pairs of; guide eyes 49 49. are

reinforcing strip 50 which forms also abase plate for the lower ends'oi the gear frame plates 26, 26.

I flfhelsteering disc 48 'isinx'ed n thelower [end portion 'of'theflowersectionf51 of anupright telescopic 'steering'shaft; Below the steering disc 48 .this shaft section, 5 v is pivoted ,in a bearing" '52 which; isfixedto and projects belowgtheframe plate 1,1this shaft section being 'retainedin its bearing a pin d1} throughflthe eridfof the shaft Q tively. to-the fulcrum of which la ed- A h r .backadjustmeht relatively thereto 7 below the bearing. The upstanding major por-' tion of this shaft section51, above the disc; is V tubular and has a longitudinal slot 54 extending diametrically through it, this.;tubu1ar slotted portionterminating at the top in anjannular cap 55, at about two-thirds of the distance upwardly' from the frameplate 1 to the level of theseesaw' 'member 17 (Figures l and 4).

The'upper' section 56 of the telescopic steering shaft telescopes downward into the lower tubular-,,section 51 forfree longitudinal sliding movement therein. These two shaft sections151 and 56 are coupled together to rotate as a unit-at all times irrespective; of ,their relative sliding tele- I .s'copic movement, bymeans of a crosspin 57 fixed in the lowerv end ofthe upper section 56 and projecting through the slot 54 at both sides of thelower. section 51 (Figures 1 and 4),. The upper shaft section 56 projects above the seesaw member l7through a-longitudinal slot 581m the latter,,which provides for thearcuate movement of the rocking seesaw'member. This upper 'shaf t section 56 is carried by the seesaw member 1'] to moven pand down therewith, by means of a collar 59 fixed against upward movement on, the upper shaft'section 56 above the seesaw member and cohically taperedonits lower side for smooth sliding and angular engagementwithithe edges of the slot 58 in .the seesaw member. The-upper s'teeringshaft; section 56 isthus carriedby the seesaw member, 17 at a location, thereon'conlow veniently'forwardfrom its narrower seat for'm ing portion at the rear end thereof.

.At; a convenient distance above its supporting V co1larU-59 the shaft section. 56 terminates. in a steering head 60; A combined hand hold and steering handle 61 has a forwardly projecting horizontal T-stem 62 passingthrough the. steel?- ing head 60 and adjustably. held therein byl a thumbscrew'63, the stem 62 desirably-having a fiat thereon to be engagedby the screw. It will" be obvious that the handheld provided by. the steering handle 61 will rise and falhwith the rear-end portion of the. seesaw member l7 and lwill be' maintained in substantially uniform spaced relation above this seesaw member, relait may beadhand held 64 is providedconveniently rearward from ihe front seat-forming portion of the seesaw member 17 by whichfltliis f ront hand hold is carried; This hand hold 64 has a vSirnilar seatbacksor backrests 69, -69 are:=re-

co-operative relation therewith, these backrests' V facing towards each'other and towardstherespectivehandholds.) The bacirrests. 69, 69 are adjustable alon'gthe seat form ing end portions of the; seesaw member '17 toward and V away from 1 .m r-i Th l a s-fi9 69 was itsflfulcrum rod 18 ineorder to enableridersof difierentg weight to balance each other on the :spectivel-y adjustablyjmou ntedon the seat-formilf-m H ,in g end 'portions of the seesaw'mernber 17-. out' 'wardly, from the hand holds 51 andfiand in hand hQl ds 61 and '64 being correspondingly but independently adjustable'co-operate in enabling the" riders to maintain their position without slipping. The two backrests 69, 69 may be of identicalconstruction, .as shown in thedrawings,

.a'neror m'eu, for the most part'at least, from suitably'sl'iaped s'heet metal. Each of the seat-forming end portions of the seesaw plate member 1'7 7 hasprovided through it"along it's centerline', a series of apertures 70, '70 shown as five in num-- her, which are utilized for holding the backrest in adjusted position.

The backrest 69 is shown as of substantially I semi-circular shape andas rising perpendicularly which extends straight down at the edge of the seesaw member plate 17 below which this lug is over t'o project inward, thus forming a hook end '72whichengages with, or hooks, beheath 'the lower side of the seesaw member 1'7 for holding down the backrest 69, preventing it from tilting backward while providing for it being freely tilted forward on the seesaw member. The rear edge of the hook end '72 is shown as projecting. slightly to the rear edge of the'vertical side portion '71 of the lug, so as betterto serve as a fulcrum in the tilting or swinging movement ofthe backrest. The vertical lug'portion '71 may slightly frictionally grip'the'edges 'of th e seesaw member, so as to prevent undesirable looseness of the backrest. V The backrest '69 at its back rigidly carries a downwardly-"projecting stud '73 which may pass freely th'rough any one of the apertured holes *70, '70'and for increased security of engagement projects somewhat below the lower side of the seesaw member 17, and will securely hold the backrest against slipping. By tilting the backrest 69 forwardly the stud '73 will be withdrawn from an aperture '70,.permitting the backrest then to be-moved 'slidably along the seesaw memberand its'stud '73 to'be re-engaged in another aperture "70 by swinging the backrest rearwardly to its normal position at a different position or adjust- "ment relatively to the fulcrumrod 18 of the seesaw member.

- Besides the co-operatingadjustable seat backs and hand holds 61-and 64 further means "are provided for balancing an excesso'f weight on oneend of the'seesawmember'l'l, suchmeans being shown; as an adjustable spring counteribalance. In the illustratedconstructio'n, two

extensible or retractile coiled counterbalance springs '74 and are adjustably connected together in series relation by means of a turnbuckle "76 of substantially usualj'construction. Une'or'the'sesprings '74 is shown as longer and is also somewhat weaker or less resistant, as indi-- fcated by'its extension, than the other spring '75.

The free end of theiohger spring '74 is shown as disconnectibly'anchored to the platform frame plate 1 just atthe front of the gear frame 26 by means of a hook '77 which is'secured by. bolts 1 3,0 and to the frame plate 1.

"I8, '78 to the upper side of the reinforcing strip x Y The remote or outer end of the other; or shorter spring '75 is shown as dlsconnectibly attached to the front end of theiseesaw member 1'7 by means of shock. '79 below the seesaw member and securedrtherew by-bolts' 80, 80 having'flat heads countersunk into the upper side of the seesaw member.

The springs '74- and '75 may be adjusted means'of theturnbuckle '76 to compensate for a" heavierrider'on the rear seat of the seesaw member, particularly in case, for example,:the-

rear rider should be an adult with a small childv as a front rider; i Furthermore, with no'front rider. and in lieu thereof, the above describedadjust able spring counterbalance provides: for the use of the traveling seesaw device. by a single rider,

whose weight on the rear seat would be counterbalanced by a corresponding adjustment of the springs '74, and '75. When there is not'too much diiferen'c'e in weight between a front rider and a rear steering rider, the upper spring '75- may be disconnected fromits hook"'79' on the seesaw member; or the lower spring 75- may also disconnected and the retractile counterbalanclng connection comprising-the springs '74 and 15mm their -turnbuckle '76 then entirely removed.

The double-pointed arcuate arrow towards the front end of'the seesaw member 17 (Figure 2) indicates the complete rocking movement-of this member, the front' andrear outside and arrows show the next immediate direction of rocking movement of the seesaw member in the forward travel-of the device with the cranks'2'7' and 28 positioned as shown, the forward direction of rotation of the traction wheel 3 being indicated by the arrowthereon, while the forward direction of travel of the device is indicated by the outside front straight arrow. The operation of the travel- .3

ing seesaw device, to whatever extent not obvious, I

isbelieved to have been already fully described in connection with the description of its con struction. It is obvious that various modifications maybe made in the construction shown in 1. In a traveling seesaw device, the combina-. tion'of a i'rameincluding an upright thereon, a

seesaw member pivoted on the upright to extend fore and aftof the frame, supporting wheels for the frame to include a traction wheel and a steering wheel, meansfor driving the traction wheel from the. seesaw. member, an upright sectional telescopic steering shaft to which the sections are coupled together to turn as a unit irrespective of their relative telescopic movement, the lowermost section of said shaft being mounted -on the frame and the uppermost section of this shaft being carried by the seesaw member tovmove up and down therewith at a point towards one end thereof from its pivot, steering connections between saidQlowermost shaft'section and the steering wheel, and a steeringhandle fixed on the said uppermost. shaft; section above "the seesaw Imember for adjustment thereon relatively to its fulcrum, an end portion-of theseesaw member "having a longitudinal series of holes therein sub- 'stantiallyaiong its center'line, the backrest at its back rigidlyfcarrying a downwardly-projecting stud freely removably to enter any oneof said holes, the backrest having forwardly extending side arms the forward end portion of which clear the edges 'of the seesaw member and leave its upper side unobstructed, and downwardly projecting lugs carried by the forward end portion 'of the side arms to extend freely past the edges of the seesaw member and having inturned prothereon at an elevated position, supportingwheels for the frame to include a traction wheel, a small spur gear coaxially connected to the traction wheel to drive the latter, a largerspur gear meshing with said smaller gear, a crank coaxially connected to the larger gear for rotatingthe-latter, and a connecting rod pivotally connecting the crank to the seesaw member at a point farther removed from its fulcrum than the length of the crank, whereby the multiplying action of the said gears will correspondingly increase the speed 0 travel of the said'device. i

5. In a traveling seesaw device, the combination of a frame, a seesaw member fulcrumed at an elevated position on the frame, supporting wheels for the frame toinclude a traction wheel,

and operating mechanism connecting the seesaw including a crank shaftjournaled on the frame and provided with opposed cranks, a connecting rod operatively connecting one of these cranks to the seesaw member at one side of the fulcrum of the latter, and a two-partconnecting rod of which the parts are'relatively telescopically freely slidable longitudinally of onefanotherwith one of its said parts pivoted on the other crank and with its other said part pivoted to the seesaw member at the other side of its fulcrum from the said operating connected connecting rod.

6. In a traveling seesaw device, the combination of a frame, a seesaw member fulcrumed atan, elevated position on the frame, -supporting wheels for the frame toinclude a traction wheel, and operating mechanism connecting the seesaw memberwith the traction wheel, such mechanism including acrank shaft journaled on the frame and provided with opposed cranks, a pair of longitudinally telescopic connecting rods respectively pivotally connecting thc cranks to the seesaw ber may be adjusted by adjustably lengthening or shortening this operating rod. a I

V 'rnoivms SERPICO.

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