US3494613A

US3494613A - Rocking amusement device

Info

Publication number: US3494613A
Application number: US679006A
Authority: US
Inventors: Herbert M Hatfield
Original assignee: JAMISON Inc
Current assignee: JAMISON Inc
Priority date: 1967-10-30
Filing date: 1967-10-30
Publication date: 1970-02-10
Anticipated expiration: 1987-02-10

Description

1970 H. M. HATFIELD ROCKING AMUSEMENT DEVICE Filed 001;. 30, 1967 I/vvs/vrae K525527111. Har /51.0

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United States Patent 3,494,613 ROCKING AMUSEMENT DEVICE Herbert M. Hatfield, Downey, Calif., assignor to Jamison, Inc., Torrance, Calif, a corporation of California Filed Oct. 30, 1967, Ser. No. 679,006 Int. Cl. A63g 31/02 US. Cl. 272-1 6 Claims ABSTRACT OF THE DISCLOSURE An amusement device of the type in which a rockable member is supported by one or more upright helical or coil springs. The upper end of each helical spring is secured to the rockable member by means of a helical spring fixed to a cylindrical tube forming a male member and the lower end of each spring is secured to a base by means of a flanged locking nut.

Background of the invention This invention relates generally to rockable amusement devices of the type employing one or more upright helical springs, and, more particularly, to specific arrangements for mounting the springs to the rockable portions and to the bases of the legs of the devices, and also to improved bases for engaging different grades of ground.

There are various types of childrens playground equipment comprising platforms ofditferent configurations which are supported by upright helical or coil springs for rockable movement. Such playground equipment comprises either generally fiat platforms which accommodate several children, and are supported generally by three helical springs, or single seated devices having a configuration, for example, of a rocking horse, and are supported by a single helical spring. In both cases, it has been the general practice to support each helical spring in a generally vertical position with the upper end of the spring connected to the rockable device, and the lower end of the spring connected to a base member secured to the ground, by placing a metal bar across the upper and lower convolutions of the springs and by tightening down nuts on bolts which pass through the bars.

This type of a helical spring mounting arrangement has the disadvantage that oftentimes the bar which secures the upper and lower portions of the helical spring to th rockable member and base, respectively, yields when the nut is threaded tightly upon the bolt, thus resulting in an assembly which is capable of slipping. Also, the bars generally employed for mounting helical springs have only about 10% bearing surface engaging the end convolutions of the springs. As a consequence, the conventional coil spring mounting arrangement for rocking amusement devices sometimes becomes loosened, thereby creating a safety hazard and requiring reassembly of the spring to the rockable platform or base.

Summary of the invention It is an object of the present invention to provide a rockable playground device having an improved helical spring mount A further object of the invention is to provide an improved rocking amusement device employing three coil spring-type legs, and an improved base for the legs which is capable of conforming to different grades of ground supporting the amusement device.

According 'to the principal aspect of the present invention, there is provided a rockable amusement device having one or more helical spring-type supporting legs. The helical spring is connected at its upper end to the lower part of the rockable member of the amusement device by threading the spring onto a threaded male eleice ment which comprises a tube having a convolution of a second helical spring secured thereto. The lower portion of the helical spring is afiixed to the base of the leg by means of a locking disc. The disc has a circular body with a flange extending outwardly from a portion of the circular periphery thereof. The circular body of the locking disc is disposed within the cylindrical channel in the helical spring with the flange resting upon the upper surface of the convolutions. The disc is threaded downwardly to the bottom of the spring until the flange rests upon the upper surface of the lowermost convolution. The locking disc is then secured by suitable fastener means to the base. By use of the locking disc having a flange as above described, a substantially greater bearing surface is provided for engaging the lower convolution of the coil spring than is provided by the bar lying across the end convolution of a helical spring in a conventional helical spring mount.

In the preferred embodiment, there is also provided 2. lug depending downwardly from the lower surface of the locking disc which engages an opening in the base so as to prevent rotation of the disc with respect to the spring and, thus, overcome the slippage problem which exists in the conventional helical spring mounts.

In the preferred embodiment of the invention, wherein the rockable member of the amusement device is supported by a plurality of vertically inclined legs, the base of each of the legs includes a cylindrical tube, the upper end of which is connected to the coil spring of the leg, and the lower end is embedded in the ground or a concrete footing in the ground. A plate adapted to engage the upper surface of the ground includes a cylindrical sleeve having a bore therethrough. The longitudinal axis of the bore is disposed at an angle, when the plate is horizontal, which is substantially equal to the angle of the legs. The cylindrical tube of the base is slidably mounted in said bore. By rotating the plate about the tube, the plate may be positioned to conform to different gradings of ground upon which the amusement device is supported Further objects, aspects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings, wherein:

Brief description of the drawings FIGURE 1 is a side elevational view of the preferred rocking amusement device of the invention;

FIGURE 2 is an enlarged vertical section taken along line 22 of FIGURE 1 showing one of the legs of the amusement device;

FIGURE 3 is an enlarged vertical section taken along line 33 of FIGURE 2, showing the mounting arrangement for the upper portion of the helical spring of the FIGURE 4 is an enlarged sectional view taken along line 44 of FIGURE 2, showing the locking disc for securing the lower portion of the helical spring to the base of the leg; and

FIGURE 5 is a perspective view of the locking disc, showing the bottom thereof.

Description of the preferred embodiment Referring now to the drawing in detail, there is illustrated in FIGURE 1 a rocking amusement device, generally designated 10. The device includes a relatively flat circular platform 12 supported preferably by three legs, each generally designated 14. A cylindrical wall 16 is welded to the top of the platform 12. Rails 18 extend around the major portion of the upper edge 19 of the Wall 16. The wall 16 and rails 18 provide a compartment in which children may play on top of the platform 12. It is to be understood that the above described platform is given by way of example only, and not by limitation.

20, and an upright coil or helical spring 22. Since a portion of the legs are formed-of the helical springs 22, it can be readily appreciated that the platform 12 may be rocked in a generally horizontal plane.

In the preferred embodiment of the invention, the three legs 14 are substantially equidistant from each other, and extend at an angle downwardly-and outwardly from the bottom 24 of the platform with their longitudinal axes converging substantially to a common point above the center ofthe platform. It is preferred that the legs extend at an angle of about 75 with respect to the ground 25 to provide maximum stability of the platform 12, yet permit the platform to be readily rocked by children.

Reference is now made to FIGURE 2 which illustrates in detail one of the legs 14 of the device 10, the other legs being identical. The base 20 of the leg includes a cylindrical tube 26 having its lower end embedded in a concrete footing 28 in the ground 25. A generally flat circular plate 30 is welded to the upper end of the tube 26. The lower.- most convolution 32 of the helical spring 22 is supported by the upper surface 34 of plate 30.

A mounting plate 36 is welded to the bottom 24 of platform 12 beneath the cylindrical'wall 16, thereby providing additional support for the wall. A cylindrical tube 38 is welded to the plate 36. The tube 38 has an outer diamter less than the inner diameter of the convolutions of the spring 22 so as to be capable of receiving the upper end of the spring.

As seen in FIGURE 2, the longitudinal axes of the tube 38, the helical spring 22 and the tube 26 are coaxial and thus disposed at an angle of about 75 with respect to the horizontal ground 25.

The upper end of the spring 22 is mounted to the lower part of the platform 12. by welding a convolution 40 of a second spring on the outer surface of the tube 38, as best seen in FIGURE 3. The convolution 40 has generally the same dimensions and configuration as the convolutions of the spring 22, except that the spacing between the ends 42 and 43 of the convolution 40 along the longitudinal axis of the leg is slightly less than the spacing between the

upper convolutions

44 and 45 of the spring 22. It can be appreciated that by the provision of the convolution 40 on the outer surface of the tube 38, there is provided a threaded male element.

When the spring 22 is initially being assembled to the platform 12, the spring is threaded onto the tube 38 with the upper convolution 44 of the spring engaging the convolution 40 as illustrated in FIGURE 3. Since the axial be readily appreciated that the convolution 40 could be extended, if desired, to a second convolution for further frictional engagement with the helical spring 22.

The lower portion of the spring 22 is secured to the plate 30 by means of a locking disc, generally designated 50. The disc includes a circular body 52 with generally flat upper and lower surfaces 53 and 54, respectively. The body 52 has a diarneter slightly less than the inner diameter of the convolutions of the spring 22. I

The disc 50 includes an outwardly extending flange 56 which extends about only a portion of the periphery of the circular body 52, as best seen in FIGURE 4. The flange 56 slopes from one end thereof 58 adjacent to the upper surface 53 of the body 52 downwardly toward the othenend 60 of the flange which is closer to the lower surface 54 ofthe body. The slope of the flange 56 is substantially equal to the slope of the convolutions of the 4 Spring 22 so that when the disc 50 is inserted into the in terior of the helical Spring 22, the entire flange 56 will rest upon the upper surface of the convolutions of the spring and engage the same in a similar fashion to a threaded male member engaging a threaded female member.

It is preferred that the flange'56 extend at least 180 about the periphery of the circular body 52 of the locking disc to provide adequ'atebearing surface 'for engaging the upper surface of the lowermost convolution 32 of the Spring 22. The flange, however, must extend only partially about the periphery of the body 52 in order to permit the disc 50 to be inserted into the interior of the helical spring 22 and to be threaded therein down to the lowermost convolution 32. In the preferred embodiment of the invention, the flange extends approximately 210 about the periphery of the body 52 of the locking disc, which permits the disc to be readily inserted into the spring 22, yet provides a substantial amount of bearing surface for engagement of the lowermost convolution 32 of the spring.

As best seen in FIGURE 2, the convolution 32 of the spring 22 is generally normal to the longitudinal axis of the spring so that almost the entire lower surface of the convolution 32 engages the upper surface 34 of the plate 30 of the base. Since the convolution 32 is generallyy normal to the longitudinal axis of the spring, the end 66 of the convolution contacts the lower surface 67 of the next adjacent convolution 68. As a consequence, when the locking disc 50 is threaded down to the lower end of the spring 22 so that the lower surface 54 engages the upper surface 34 of plate 30, the leading edge of the flange 56 adjacent to the end 60 becomes wedged between the lowermost convolution 32 and the adjacent convolution 68.

In order to prevent the disc 50 from unthreading from the convolutions of the helical spring 22 when seated against the plate 30, there is provided a lug 70 which depends downwardly from the lower surface of the circular body 52. An opening 72 is provided in the plate 30. The opening is so located that when the disc 50 is threaded to the bottom of the spring 22, the lug 70 will engage into the opening 72, thereby preventing any further rotation of the disc.

The disc 50 is secured to the plate 30 when threaded to the lower end of the spring 22 by means of a bolt 76 fixed to the plate 30 and extending upwardly through a central bore 78 in the disc. A look washer 80 is positioned over the upper end of the bolt 76 and a nut 82 is threaded onto the bolt to force the flange 56 of the locking disc downwardly upon the upper surface of the lowermost convolution 32 of the spring, thereby securely clamping the lower end of the spring 22 to the base 20.

The base 20 includes a circular plate generally designated 86, having a downwardly curved top 87 and a peripheral annular flange 88 which engages the ground 25 to provide support for the tube 26 in addition to that derived by the embedding of the tube into concrete 28. A sleeve 90 is positioned in a central bore 92 extending through the top 87 and secured to the plate by welding or the like. The sleeve 90 has a bore 94 therethrough, the longitudinal axis of which isdisposed of at an angle, when the plate is horizontal, which is substantially equal to the angle of the leg 14, and consequently the tube 26.

I The tube 26 is 'slidably mounted within the bore 94. A

' may still be positioned so as set screw 96 mounted in the sleeve 90 engages the outer surface of the tube 26. By this construction the plate 86 may he slid longitudinally on the tube 26 and may be rotated about the tube in order to conform to different grades of ground upon whichthe amusement device 10 is mounted. As a consequence, the device 10 employing bases 20 as described herein, may be mounted on sloping ground, and the flange 88 of the plate 86 of each leg to firmly seat against the surface of the ground.

While the preferred embodiment of the invention has been disclosed herein as constituting a platform employing three legs 14, it is understood that the spring mounting arrangement of the invention may be employed with rocking amusement device employing as few as one leg or more than three legs, and could be utilized in any other type of assembly wherein it is desired to securely mount the ends of a helical spring.

Although I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein, but is to be accorded the full scope of the claims so as to embrace any and all equivalent structures and devices.

I claim:

1. A rocking amusement device comprising: a rockable member; at least one leg extending downwardly from said member; said leg including an upright helical spring and a base having a longitudinal axis coincident with a longitudinal axis of said helical spring and extending therefrom and adapted to 'be secured to the ground; first securing means including a cylindrical tube fixed to the bottom of said rockable member with its longitudinal axis coincident with the longitudinal axis of said leg, the outer diameter of said tube being less than the inner diameter of the convolutons of said spring; a convolution of a second helical spring having generally the same dimensions as that of the upper convolutions of said first mentioned spring, said convolution of said second spring embracing said tube and being fixed thereto to provide a threaded male element; and the upper convolution of said first mentioned spring being threaded onto said male element, second means securing the lower part of said spring to said base; said second securing means comprising a locking disc, said disc including a circular body having a diameter less than the inner diameter of the convolutions of said spring, a flange extending outwardly from only a portion of the circular periphery of said body, said body being disposed within the cylindrical channel in the helical spring defined by the inner periphery of the convolutions thereof with said flange threadably engaging the upper surface of the convolutions of the spring, and fastener means releasably securing said disc and, hence, said spring to said base when said disc is threaded to the lower end of said spring and said flange engages the upper surface of the lowermost convolution of the spring.

2. A device as set forth in claim 24 wherein said body has a lower surface, a lug depending downwardly from said lower surface of said body, an opening in said 'base, said lug engaging said opening when said disc is threaded to the lower end of said spring.

3. A device as set forth in claim 1 wherein said flange extends more than 180 about the circular periphery of said body; said body having upper and lower surfaces, a lug depending downwardly from said lower surface; an opening in said base, said lug engaging said opening when said disc is threaded to the lower end of said spring; and said flange sloping from one end thereof adjacent to said upper surface of said body downwardly toward the other end thereof adjacent to said lower surface of said body,

the slope of said flange being substantially equal to the slope of the convolutions of said spring.

4. A rocking amusement device comprising: a rockable member; at least one leg extending downwardly from said member; said leg including an upright helical spring and a base adapted to be secured to the ground; first means securing the upper part of said spring to said member; second means securing the lower part of said spring to said base; said second securing means comprising a locking disc, said disc including a circular body having a diameter less than the inner diameter of the convolutions of said spring, a flange extending outwardly from only a portion of the circular periphery of said body, said body being disposed within the cylindrical channel in the helical spring defined by the inner periphery of the convolutions thereof with said flange threada'bly engaging the upper surface of the convolutions of the spring, and fastener means releasably securing said disc and, hence, said spring to said base when said disc is threaded to the lower end of said spring and said flange engages the upper surface of the lowermost convolution of the spring, wherein, a plurality of said legs extends at an angle downwardly and outwardly from said rockable member, said legs being substantially equidistant from one another and having longitudinal axes; and said longitudinal axes of said legs converging to substantially a common point above said member.

5. A device as set forth in claim 4 wherein there is provided three of said legs, and the angle of each of said legs with respect to a horizontal plane being approximately 6. A device as set forth in claim 4 wherein each of said bases of said legs includes: a cylindrical tube being adapted to have one end thereof embedded in the ground at said angle; a plate adapted to engage the surface of the ground; said plate, including an upright sleeve, said sleeve having a cylindrical bore therethrough with the longitudinal axis thereof being at an angle, when said plate is horizontal, which is substantially equal to said first mentioned angle; said tube being slidably mounted in said bore, whereby said plate is rotatable about said tube; and means for releasably securing said plate to said tube.

References Cited UNITED STATES PATENTS 326,721 9/1885 Crandall 272-52 X 1,956,846 5/ 1934 Williams. 2,184,453 12/ 1939 Hayes 272-78 2,949,298 8/ 1960 Speelman 272-60 X 2,996,205 8/1961 Smith 272-66 X D 198,923 8/ 1964 Mitchell.

3,292,924 12/1966 Wormser et a1. 272-54 FOREIGN PATENTS 330,206 10/ 1935 Italy.

ANTON O. OECHSLE, Primary Examiner ARNOLD W. KRAMER, Assistant Examiner US. Cl. X.R. 267-1