CA1069951A - Spring supported device such as a playground toy - Google Patents

Abstract

A B S T R A C T

A spring supported device such as especially a playground toy comprising a heavy coil spring the opposite ends of which are affixed to mutually movable parts such as a seat element and a support element anchored to the ground, respectively, so as to enable said parts to be moved resiliently by compressing, expanding or bending the spring, the spring at least at one end being wound and shaped in such a manner that the outermost winding has a small pitch and defines a support surface substantially normal to the axis of the coil spring, this outermost winding continuing, towards the opposite end of the spring, in a winding portion of increased or increasing pitch;
for eliminating the jamming hazard in the narrow wedge shaped space between the outer winding portions there is mounted, at some point or area in this space, a distance piece between the windings, and connector means are provided for clamping the windings against the distance piece in order to lock the windings rigidly together at a place where the distance between the windings is large enough to exclude jamming of fingers or toes when the device is in use.

Description

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The present invention relates to heavy coil springs and more particularl~ to devices such as playground toys having one or more exposed~ heavy coil springs mounted between two mutually movable parts, eOg. a toy seat element and a sup-port element anchored to the ground, so as to enable said parts to be moved resiliently relative to each other by com-pression, expansion or bending of the coil spring, a typical example of such a device being a seesaw type apparatus in which the seesaw borad is centrally supported by means o~ a : 10 coil spring hav~ng one end rigidly secured to the seesaw board and its other end rigidly secured to a ground anchored support element. Instead of a seesaw board the spring may serve to support a seat for a single child, ~ho may then swing the seat resiliently en~wise or crosswise on the spring by causing the spring to bendO
Springs of the type considered normally have, at least at one end, an outermost winding of small pitch which is wound and shaped so as to define a support surface substan~
~ : tially normal to the axis o~ the coil spring, the said outer-- 20 mos t winding continuing, towards the opposite end o~ ~he sprin~, in a winding portion of gradually increasing pitch and then in a main body portion of the spring wherein the windings ha~e a constant, relatively large pitcho Even the spring windings are genarally mutually spaced so much that they canrlot possibly be clamped entirely t~ogether in normal use o~ the device, clamping problems may neve~the-less occur adjacent the ends of the spring, where a wed~
shaped space exists between the ou~ermost winding portio~s of small p~t~ and the ~ollowing winding portion of increase~
pitch. It may happen that a child holds a finger in the sa~d space when the re~pective winding portions at the particular

2 - ~

106~95il place are moved towards each other9 mostly by a bending of the spring, whereby the finger may be seriously injured.
In order to counteract this jamming ha~ard the end of the spring might be covered by a surrounding shield9 but the same hazard is then liable to occur between the end edge of the shield and other windings of the coil spring. ~lternatively the spring could be shaped so as to extend along a broken line between the respective winding portions in such a manner that the said wedge shaped space is entirely avoided7 but slnce nor-mally the spxings in question should be wound from a relativelythick spring steel rod~ e.g~ of a diameter of some 10~20 mm, it should normally be pre~erred for reasons of security to maintain the traditional spring sh~pe, i.eO to make use of a spring presenting the said wedge shaped space adjacent the ends thereof.
It is a purpose of the invention to provide a device of the type referred to in which the said jamming hazard is mini-mized or elimlnated in a simpl~e manner.
The de~ice according to the invention is characterized in that between the outermost winding portion of small pitch and an area or point of the winding portion of increased pitch there is mounted a substantially non-compressible distance element 9 and that between said winding portions in or adjacent the same area or poi~t there is provided non-stretchable connector means preventing the respective winding portions from ~eing moved a~ay from each other. The said distance element and connector means being mounted at one or more places in which the respec~
tive windiny portions are axially spaced ~om each other, the innermost portions of the said wedge shaped space will thus be locked agaînst both contraction and expansion, and though out-side this non~dangerous space there will still exist ~ wedge ~6g~s~

shaped space, the wi~din~s at the inner end of this space will be located in spaced relationship, and besides the wedge angle defined by the windings at this place will be relatively lar~e, in practice so large that the opposed winding portions cannot be forced tog~ther to a mutual distance smaller than the said distance at the locked area. When this distance is large enough to easily allow a finger to be introduced between the windings adjacent the bottom of the outer wedge shaped space the finger may then not in any way be jammable1 neither adjacent the bot- -tom portion of the outer wedge space nor in this space at all.
In other words the said distance element and connector means~ which are advantageously mounted immediately ad;acent each other, serve to provide a mechanical and non-resilient shor~-circuit b~tween the outermost winding and a winding port-ion axially spaced therefrom, whereby the innermost wedge shaped space is bridged in a stiff manner eliminating the ~amming haæard.
In the ~ollowing ~he invention is described in more detail, by way o~ ex?mples, with reference to the accompanying draw-ing9 in which:-Fig. 1 is a perspective view of a playground toy accordingto the invention, Fig~ 2 is a perspective view of the carrier spring of the toy, Fig. 3 is a perspective view of another playground toy accordiny to the invention, Fig~ 4 is an elevation, partly in section, of the locking means used in the lower end of the spr~ng shown in Fig. 2, ~ ig. S is an elevation of a fraction of the top end o~
the spring provided with modi~ied locking means, and Pig. 6 is a sectional view of further modified locking means.

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The toy shown in Fig. 1 comprises a seat portion 2 secured to the upper end of a strong coil spring 4, the lower end o which is secured to a mounting plate 6 which is supported or anchored to the ground, in a manner not shownO A child sitting on the seat 2 will be able to make the toy carry out various swinging movements, mainly by causing the spring 4 to be bentO
As shown in more detail in Fig~ 2 there is secured to the upper end of the coil spring 4 a mounting bracket 8 to which the seat portion 2 is secured. The planar bottom side of the bracket memker 8 is rested against the top side of the upper-most winding 10 of the spring, this winding having a small pitch and having its top side shaped so as to be situated in a plane substantially normal to the axis of the springO The top winding continues in a winding portion 12 having a downwardly increasing pitch until at a wlnding portion 14 it continues in the main spring portion having the characteristic pitch of the springO The bracket member 8 is secured to the top end of the spring by means of a U-bolt 16 engaging a portion of the upper winding 10 preferably at a place underneath the free end port-ion 18 of the spring rod? whereby~ when the U-member 16 is tightened upwardly by means of nuts ad;acent the top side of the bracket member bottom7 the flattened spring end portion lB
is tightly clamped together with the underlying winding port-ion, and a diametrically opposed U-member 20 projecting ~rom the bracket 8 down about the winding portion 120 At this place, in the space between the winding portions 10 and 12 there is mounted a distance piece formed as a plate member 22, the op-posed ends of which is provided with a notch 24 engaging with the leg portions of the U-member 20 in such a manner that the distance piece 22 is held by the U-member in a non~displaceable manner. The plate member 22 fills out the space between the " ~L~i9~,9S~

windin~s 10 and 12 so as to be tightly clamped therebetween when the U~member 20 is tightened upwardly by means of nuts 260 As indicated7 the platé ~ember 22 may, of course9 be com~
posed of two or more superimposed, thin plate membersO
The lower end o~ the spring 4 is secured to the base ele-ment 6 ih an exactly corresponding mannerO It is shown by way of example that the distance piece 22' may be constituted by a cylind~ic rod elément, but it will be unde~stood that the in-ventioh is not limited to any partlcular sha~e of the distance element. As shown in Fig. 4 the opposèd ends of the rod ele-ment 22' a~e preeràbly conca~ely récessed as shown at ~4' in order to be safely held between the legs o~ th~ U-bolt 20'.
It ~ e appreciatèd ~hat wi~h thë mounting arr~ngement described there is e~tablished a both pull- and pressu~e-stiff co~nection between the win~ing portions 10 and 1~, whereby the movements of the spring 4 ~annot give rise to an~ jamming ef-fèct ln the narrow wedge shaped space 11 between the winding portions. In the wedgé shaped space 13 at ~he other side of the ~onnector parts 20 and 22 ~he distance betwee~ the winding p~rtions is relatlvely large~ and even if this distanc~ is ~aused to be red~ced during use o~ the toy the space will still be wide enoUg~l to exclude any jam~ing.hazardc It should be mentioned that it is~ of course, well known to make ~se of U me~bers 16 and 20 for cla~ping the upparmost winding 10 against a mountin~ bracket 8, whereby the round end portion o~ the U-membe.r 20 may act as a sti~f distanc~ piece between the windin~ portions 10 and 12 so as to prevent com-pression of the narrow wedge shaped space between these wi~d-in~s; however~ in that case the distance piece is not in rigid

3 connection with both winding portions, and ~amming m~y occ~
therefore~ between the distance piece and the windiny por~io~

12.
~ 6 -~0~S19Sl The distance piece 22 should not necessarily be mounted exactly the same place as the connector member 20, since the combined e~fect of the distance piece and the connector member will be substantially the same if the distance piece is placed e.gO a few centimetres from the connector member 20 as seen in the circum~erential direction o~ the spring 4, when it is only ensured that the distance piece is sa~ely secured in the space between the windings 10 and 120 The non-stretchable connection member 20 should not necessarily be constituted by an element additionally serving to secure the bracket member 8 or the plate member 6 to the spring9 it may be a closed member de-fining a certain maximum distance between the winding portions~
while as the intermediate distance piece there is used a wedge element or another element, the effective thickness o-f which is increasable in such a manne:r that the winding portions 10712 are forced away from each other~ against the opposed ends o~
the surrounding closed connector element corresponding to the member 200 As an example it is illustrated in FigO 5 that the connector member 20~' may be a closed eye member which is~ -~ 20 prior to the mounting of the spring end to i~s associated part9 :~ slipped into its position along the outermost winding portions~
the eye member being introduceable onto the windings just like : a key being introduced onto the windings of a key-ring, iOeO
by mechanically forcing the free, thin end of the outer wind-ing 10 away from the underlying winding portionO The eye member is pushed in the direction of the arrow A until it is stopped by its engagement with both the winding portions 10 and 12.
A distance piece 22'' is placed between the winding portions 10 and 12, in the outer wedge shaped space 13, and pushed along the windings in the direction of the arrow B towards the narrow wedge space 11 until both its opposed ends engage 395~

with the respective winding portionsO The length of the di-stance piece 22'' is so adapted that the distance piece will be stopped by -the said engagement when it reaches a position inside the eye member 20''o The members 20'' and 22'' may be provided with special means ~or holding them in their positions, e.gO clamping screws (not shown) cooperating with one of the windings 10 or 12, or they may be pushed or hammered into their positions by such high forces that they will safely hold themselves by their mutual clamping action ad;acent their re-spective opposite endsO
As sho~n in dotted lines in Fig~ 5 the distance piece 22'' should not by necessity be mounted just inside the eye member9 i.e. in the eye opening thereof~ as the desired result is ob-tainable even if the final position of the distance piece is somewhat of~set from the eye member, whether at one or the other side of the eye memberO
FigO 6 shows an embodiment in which the locking means are constituted by a rigid block member 32 provided with spaced grooves 34 for receiving the respective winding portions and a cover plate 36 which is securable to the block member 32 by means of a screw 38, upon the block member being inserted ra-: dially onto the spring winding portionsO The block member serves to locl the winding portions against movement both towards and away from each other 9 and as it can be mounted at one place only9 where the natural distance between the windings corresponds to the distance between the grooves 349 it will not be necessary, though maybe desirable, to lock the block member by a clamplng screw or the like against displacement along the windings~
The eye member 20' shown in Fig. S may, of course, be substituted by a U-bolt having a cross yoke and tightening nuts ~0~9~5~

corresponding to the nuts 26 in FigO 2, whereby the eye member may be actively clamped to the windings at any selected place thereon. The distance piece 22'', if mounted immediately at one side or the other of the eye member, may be substituted by a wedge shaped or frustro conical block which is urged into the space between the windings so as to clamp these against the respective opposite ends of the eye member.
As illustrated in Figs~ S and 6 the winding locking means should not necessarily as in FigO 2 additionally constitute means for securing the spring end to its associated part9 but it will be appreciated that it is advantageous to use the locking means additionally for this purposeO
By way of example ~ig 3 shows another playground toy, generally designated 309 and as clearly shown being o~ the seeW
saw type9 supported by four coil springs 4 which are all (in a manner not shown) secured to the seesaw toy 30 in the manner described h2reinbeforeO ~n this embodiment the springs 4 will not be liable to be bent9 but rather to be compressed and ex panded according to the tilting movement of the seesaw7 and the use of several springs 4 involves that the seesaw 30 is stabi lized against excessive horizontal r~tary movements.
It will be understood that the invention is not limited to spring supported playground toys, since the invention will be applicable in connection with any kind of device in which there is used one or more heavy coil springs which are exposed in such a manner that the described jamming hazards are liable to occurO
It should be mentioned that the distance element should not necessarily be provided so as to leave the narrow wedge shaped space 11 open~ the distance element may be shaped cor~
respondingly itself7 i~eO so as to fill out the entire space llo ~, ,", . ~ ..

Claims (7)

THE EMBODIMENTS OF THE INVENTION IN WHICH
AN EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS
FOLLOWS:

1. A device such as a playground toy, comprising a heavy coil spring, the opposed ends of which are affixed to re-spective opposed parts so as to render these parts mutually resiliently movable by compression, expansion or bending of the coil spring, said spring at least at one end thereof having an outermost winding of small pitch and a following winding of increased or increasing pitch confining together with said outermost winding a helical wedge shaped space, a substantially non-compressible distance element being arran-ged in said wedge shaped space between and in engagement with respective winding portions, and a substantially non-stretch-able connector means being arranged adjacent said distance element so as to hold the respective winding portions in said engagement with the distance element and prevent the winding portions from being moved away from each other.

2. A device according to claim 1, in which said connector means is mounted immediately adjacent said distance element and is length adjustable so as to be operable to clamp the respective winding portions together, against the respective opposed ends or sides of the distance element.

3. A device according to claim 2, in which said connector means is constituted by a U-bolt having a cross yoke and tightening nuts adjacent its open end.

4. A device according to claim 2, in which the connector means is arranged so as to additionally clamp the respective winding portions, spaced by said distance element, against said part affixed to the end of the spring, so as to contri-bute to the fixation thereof.

5. A device according to claim 3, in which said U-bolt extends generally in the axial direction of the spring and has its free legs projecting through holes in a mounting base plate arranged on the end of the spring.

6. A device according to claim 1, in which said con-nector means comprises connector rod means extending closely outside the space between the respective winding portions across and at both sides thereof, the distance element projecting lat-erally from said space and being provided with holes or recess engaged by said connector rod means.

7. A device according to claim 1, wherein an addi-tional freespace is defined between said first portion of said windings on said one side of said distance element.