US3420523A - Spring powered swing - Google Patents

Description

Jan. 7, 1969 E. E. FOSTER SPRING POWERED SWING Sheet Filed July 28, 1965 M z 2 3 6 El .1 W \m \H 3 Y n; \R. m C W M. 34 3 v 5 Z 2 m F INVENTOR EDWIN E. FOSTER ATTORNEY Jan. 7, 1969 E. E. FOSTER SPRING POWERED SWING Sheet Filed July 28, 1965 INVENTOR EDWIN E. FOSTER BY @W' ATTORNEY Jan. 7, 1969 FOSTER 3,420,523

SPRING POWERED SWING Filed July 28, 1965 Sheet 3 0f 5 FIG.5

INVENTOR EDWIN E. FOSTER ATTORN EY United States Patent 3 Claims ABSTRACT OF THE DISCLOSURE A swing incorporating a spring motor and an escapement. One end of a spring is attached to a storage drum. The other end is backwound on a shaft having a toothed wheel at one end. Rewinding of the spring onto the storage drum causes the shaft to rotate alternately. Engaging the toothed wheel are two pawls. The first pawl is pivotly attached to a housing and is spring biased to engage the wheel in one position and to be disengaged in a second. The second pawl is pivotly attached to one end of a bell crank arm and is spring biased to engage the first pawl in one position and the toothed wheel in a second. The other arm of the bell crank supports a swing. As the swing oscillates the pawls are alternately caused to engage the toothed wheel.

This invention relates in general to swings and, more particularly, to a swing powered by a spring motor.

It is an object of the present invention to provide a spring motor operated swing which is adapted for continuous, unattended operation over a relatively extensive period of time.

It is another object of the present invention to provide a spring powered swing which is reliable in operation and entirely safe for utilization by children of tender years without supervision.

It is another object of the present invention to provide a swing of the character stated which incorporates a simplicity of coacting mechanical elements which are not dependent upon the application of extrinsic motive means and, thus, provide a fully self-contained mechanism so that the swing may be positioned at any desirable location convenient for the users use.

It is another object of the present invention to provide a swing of the character stated which may be most economically manufactured; which incorporates novel excapernent means for periodic release of limited increments of spring energy so that a relatively extensive operational period is presented; and which is durable in operation.

Other objects and details of the present invention will be apparent from the following description when read in connection with the accompanying drawing, wherein:

FIGURE 1 is a front elevational view of a swing incorporating a spring powered mechanism constructed in accordance with and embodying the present invention.

FIGURE 2 is a vertical transverse section taken on the line 22 of FIGURE 1 illustrating the mechanism when the swing is in its forwardmost position.

FIGURE 3 is a vertical transverse sectional view taken substantially on the line 2-2 of FIGURE 1 but illustrating the mechanism when the swing is in rearwardmost position.

FIGURE 4 is a vertical transverse sectional view taken on the line 44 of FIGURE 2.

FIGURE 5 is a horizontal transverse sectional View taken on the line 5-5 of FIGURE 2.

Referring now by reference characters to the drawings which illustrate the preferred embodiment of the present invention, A designates a swing incorporating a support structure consisting of a pair of A-frames 1, 1 each having a pair of legs 2 in upwardly converging relationship and being interconnected in their upper portions by a Patented Jan. 7, 1969 hinged cross brace 3. Said A-frames 1, 1' at their upper ends are fixedly received within a housing 4 as fabricated of sheet metal stock or molded plastic, having a preferably rounded top with downwardly and outwardly inclined front and rear panels 5, 5' and end walls 6, 6. Secured within housing 4 for extension transversely thereof is a pair of spaced-apart, planar parallel plates 7 having continuous edge flanges 7 directed toward each other which are suitably secured to said front and rear panels 5, 5', as by means of screws, welding, or the like. Said plates 7 are punched to present aligned openings 8 constituting bearings for a crankshaft 9 extending therethrough in axial parallelism to the longitudinal axis of housing 4 and being located upwardly of said housing axis. Crankshaft 9 projects at one of its ends through an opening 10 in end wall 6 and in its projecting portion is bent to provide a crank arm 11 which mounts a handle 12 on its extremity.

Fixed upon crankshaft 9 between plates 7, as by a drive pin 13, is a power spool 14 for movement with said shaft. Power spool 14 may be fabricated of sheet stock and incorporates circular end plates 15 interconnected by aligned fiat transverse plates 16, 17, across the upper face of the latter is directed the tapered end of a spring motor 18 and with said end being secured thereon by a screw 19. Said spring motor 18 is of the self-coiling, constant-force ribbon type and extends downwardly from plate 16 to a storage coil 20 being wound about a drum 21 to which its opposite end is secured; said drum 21 being mounted for rotation upon a shaft 21 journalled at its ends in plates 7. It will be seen that spring motor 18 has a width substantially equal to the distance between plates 7 so as to prevent lateral displacement thereof as the same is wound and unwound from the storage coil 20 as for purposes hereinbelow appearing. As suggested above, spring motor 18 is so set and tempered as to be biased to form itself into a tight coil having a large number of turns relative to the length of the spring and having a very flat gradient so that the torque developed thereby is of substantially constant force; said spring 18 is of the type set forth and described in US. Patent No. 2,899,193.

It will thus be seen that if power spool 14 is turned clockwise, in the direction indicated by arrows in FIG- URE 2, in a spring Winding operation by appropriate manipulation of crank handle 12, spring motor 18 will be backwound thereupon and, thus, be bent counter to its normal bias so that it will tend to unwind from power spool 14 and to wind into the storage coil 20. The said two forces are thus combined to turn power spool 14 for the purposes set forth hereinbelow with a relatively high torque and maximum eflicient use of the spring material. As backwound upon spool 14, spring motor 18 will provide the energy or power for operation of the swing.

In contact with spring 18 between storage coil 20 and power spool 14 is the lower pointed end 22 of a follower arm 23 which latter is pivotally mounted upon a rod 24 journalled at its ends in openings formed in brackets 7; there being a spring 25 turned about said rod 24 and bearing at both ends against the flanges 7 of plates 7 (FIG- URE 5) and its central portion bears against the under face of follower arm 23 for urging said arm 23 upward at its lower end for reception of the same within a limit aperture 26 provided within spring motor 18 proximate its normal lower extremity so that the back winding about spool 14 will be terminated by such engagement before the entire spring ribbon has been exhausted from storage coil 20. The particular location of limit aperture 26 is a matter of choice depending upon the extent of operation desired but it has been found in practice that the same might best be located so as to cause approximately one and a half coils of spring ribbon to remain about storage drum 21.

Locked on crankshaft 9 for rotation therewith, as by means of an L-shaped pin 27, is a toothed, ratchet wheel 28; said wheel 28 being located outwardly of the plate 7. Disposed for engagement with the lower teeth of ratchet wheel 28, in order to prevent reverse rotation thereof, is a keeper pawl 29 presented downwardly of ratchet wheel 28 and which is pivotally carried at its lower end upon a pin 30 fixed in the adjacent plate 7; said pawl having a tapered upper end edge 31 for tooth engagement and a curvate camming edge 32 formed on its under surface adjacent said end 31. Pawl 29 is urged forwardly into engagement with said ratchet wheel 28 by means of a coil tension spring 33, one end of which is secured to a pin 34 extending from adjacent plate 7 and the other or lower end of which is engaged to a pin 35 carried approximately centrally of said keeper pawl 29. Thus, pawl 29 permits of rotation of crankshaft 9 for back winding of spring motor 18 but is biased so as to prevent unauthorized or premature unwinding.

Powered for swinging movement by escapement of spring motor 18 in a manner to be described below is a swing seat 36 which preferably contains a pair of leg openings 37 and is engaged on the opposite sides of its rear or back to the lower ends of rear hanger rods 38, 39. Hanger rod 38 is of general L-shape having an upper transverse portion as indicated at 38' (FIGURE 4) which is received within housing 4, below, and in axial parallel relationship with, crankshaft 9, journalled in registering bearings 40 formed in said plates 7 with the projecting end proximate ratchet wheel 28 having an end collar 41 mounted thereon. Said hanger rod 38 also passes through a bearing 1) for-med in a plate 12 planarwise parallel with plates 7 and being suitably secured to the adjacent portions of housing 4; said plate p being spaced from the plate 7 proximate end wall 6'.

Secured upon the transverse portion 38' of the hanger rod 38, downwardly of ratchet wheel 28, is a transversely bored mounting arm 42. Mounting arm 42 is drilled in its lower portion to provide an upwardly extending socket 43 for reception of the upper end of hanger rod 39' which is secured therein against inadvertent displacement as by a set screw 44. Depending from transverse portion 38 of hanger rod 38 by integrally formed eyelets e are tension straps 45, 46 which the lower ends are secured to the front side portions of the swing seat 36 (FIGURE 1). Thus, the suspension system for swing seat 36 is integrated into a unitary structure.

Mounting arm 42 includes a boss or extension 47 upon the face of same directed to the adjacent plate 7 there is pivotally mounted, as by means of a pin 48, the lower end of a driver pawl 49 presented in substantial side by side relation to keeper pawl 29 for engaging the lower teeth of ratchet wheel 28 at a point slightly advanced clockwise with respect to the engagement therewith by keeper pawl 29. Interconnecting said pawls 29, 49 for urging same normally toward each other is a short tension spring 50, one end of which being secured to a pin 51 carried substantially centrally of driver pawl 49 and the other end of which is fixed upon pin 35.

In operation the user will, by appropriate action of crank handle 12, effect a back winding of spring motor 18 upon power spool 14 as above stated; during which operation swing seat 36 will be stationary in its centered position. In this condition driver pawl 49 will be out of engagement with the teeth of ratchet wheel 28 by reason of the disposition of mounting arm 42, and keeper pawl 29 will restrain ratchet wheel 28 against counter-clockwise movement under the bias of spring motor 18. The operator will then give the swing seat 36 a slight forward starting push as toward the left hand side of FIGURE 2 can!- ing driver pawl 49 to be moved further downwardly as shown in FIGURE 2. Though gravity swing seat 36 will move returningly downwardly and upwardly to the right hand side of FIGURE 2 or in a rearward direction, causing mounting arm 42 to be rocked upwardly into the position shown in FIGURE 3 which will bring driver pawl 49 into engagement with the teeth of ratchet wheel 28 and simultaneously cause tension spring 50 to pull keeper pawl 29 downwardly away from the teeth of ratchet wheel 28, and hence, out of engagement therewith, with a concurrent stressing of spring 33 so that an escapement may be effected by release of ratchet wheel 28 for counter-clock- Wise movement under force of backwound spring motor 18. Ratchet wheel 28 will thereon apply a driving downward push upon driver pawl 49 which will tend to pivot mounting arm 42 downwardly for consequent forward rocking of swing seat 36. By such downward and forward swinging of seat 36, driver pawl 49 will be removed from engagement with the teeth of ratchet wheel 28 and thereby release the stress upon spring 50 so that keeper pawl 29 under urging of spring 33 will be restored to engagement with ratchet wheel 28 for restricting further unwinding of spring motor 18. The relationship of pawls 49 and 29 allow for controlled escapement of ratchet wheel 28 for release of a predetermined increment of energy or power from the backwound spring motor 18 to assure of continued swinging action. It should be observed that the camming edge 32 of keeper pawl 29 will abut the confronting edge of driver pawl 49 as keeper pawl 29 is returning to ratchet-engagement and thereby exert a deflecting force upon driver pawl 49 to assure of its removal from engagement with ratchet wheel 28.

Thus, spring seat 36 will move forwardly and, thence, rearwardly without further assistance of spring motor 18 until the seat has reached its rearward-most position wherein the engagement of driver pawl 49 with, and the removal of keeper pawl 29 from, ratchet wheel 28 for the bringing about of the powered push by the predetermined unwinding of backwound spring 18.

Accordingly, the swinging operation of seat 36 will continue on a to and fro basis with ratchet wheel 28 alternating being restrained and released so that the swinging will continue until spring motor 18 has been fully restored to storage coil 20, unless, for instance, the unwinding is intentionally stopped in which case the operation will be discontinued in the middle of a cycle of movement until restarted. By virtue of the nature of spring motor 18, with its tightly wound coils, a considerable interval of swinging action of swing seat 36 may be accomplished without the frequent necessity of rewinding so that swing A is rendered capable of continuous operation over a relatively extensive period of time without the intervention of supervision.

Swing A is constructed of a limited number of parts which are sturdy and durable so that the said swing is not prone to breakdown and may be most economically manufactured.

It should be understood that changes and modifications in the formation, construction, and arrangement and combination of the several parts of the spring powered swing may be made and substituted for these herein shown and described without department from the nature and principle of my invention.

Having described my invention, what I desire to obtain by letters patent is:

1. A swing comprising a frame, means defining a housing mounted upon said frame, a shaft disposed within said housing and carried on said frame, a spring motor formed from flat ribbon stock and biased into a tightly wound storage coil, means provided on said frame in spaced relationship to said shaft for supporting said storage coil, said spring motor having a normally outer end, said spring motor outer end being operatively fixed to said shaft, means for rotating said shaft for back winding said spring motor thereon from said storage coil, stop means for limiting the unwinding of said spring motor from said storage coil, a toothed wheel fixed on said shaft for rotation therewith, a pawl pivotally mounted upon said housing and engageable with said toothed wheel, resilient means secured at one end to said housing for urging said pawl into engagement with said wheel to inhibit rotation of said shaft in a spring motor unwinding direction, a body support member suspended from said frame for a swingable movement, wheel-engaging means carried by said support member for sequentially effecting release of said pawl for controlled escapement of said wheel through the unwinding force of said spring motor and for transmitting such force to said body support member for swinging action thereof, said wheel engaging means and said pawl being presented in immediated adjacency and upon the same side of said toothed wheel, a spring engaged at its ends to said pawl and said wheel engaging means for urging the same toward each other.

2. A swing comprising a frame, means defining a housing mounted upon said frame, a shaft disposed within said housing and carried on said frame, a spring motor formed from flat ribbon stock and biased into a tightly wound storage coil, :means provided on said frame for supporting said storage coil, said spring motor having a normally outer end, said outer end of said spring motor being operatively fixed to said shaft, means for rotating said shaft for back winding of said spring motor thereon from said storage coil, stop means for limiting the unwinding of said spring motor from said storage coil, a toothed wheel fixed on said shaft for rotation therewith, a first pawl engageable with said toothed wheel, spring means engaged to said housing for urging said first pawl into engagement with said wheel for inhibiting rotation of said shaft in a spring motor unwinding position, a body support member pivotally suspended from said housing for swingable movement, a second pawl engageable with said toothed wheel carried by, and pivoted upon, said body support means for engagement with said toothed wheel at a predetermined juncture during the cycle of swinging movement of said body support member, and resilient means interconnecting said first and second pawls whereby upon engagement of said second pawl with said toothed wheel said first pawl will be disengaged to allow for controlled escapement of said wheel under the unwinding force of said spring motor, said first and second pawls being disposed in juxtaposition upon the lower side of said wheel.

3. A swing comprising a frame, means defining a housing mounted upon said frame, a shaft disposed within said housing and carried on said frame, a spring motor 40 formed from flat ribbon stock and biased into a tightly wound storage coil, means provided on said frame for supporting said storage coil, said spring motor having an outer end, said spring motor outer end being operatively fixed to said shaft, means for rotating said shaft for back winding of said spring motor thereon from said storage coil, means for limiting the unwinding of said spring motor from said storage coil, a toothed wheel fixed on said shaft for rotation therewith, a first pawl member swingably mounted on said frame for engagement with said toothed wheel to inhibit rotation of the same in a spring motor unwinding position, first spring means urging said first pawl into engagement with said toothed wheel, said first pawl having a curvate camming edge on its under surface, a body support member suspended from said frame for swingable movement into a forward and rearward position, a second pawl means pivotally mounting said second pawl on said body support member for movement therewith, said second pawl being in substantially side-by-side relationship to said first pawl, said second pawl being engageable with said toothed wheel, second spring means interconnecting said first and second pawls whereby upon swinging of said body support member rearwardly said second pawl will be brought into engagement with the said carnming surface of said first pawl for effecting disengagement of said first pawl through stress of said second spring means for releasing said shaft for rotation of a spring motor unwinding direction and for presenting said second pawl into engagement with said toothed wheel for transmitting energy from said spring motor unwinding to said body support member for returningly swinging same fonwardly.

References Cited UNITED STATES PATENTS 2,998,612 9/1961 Saint et al. 38 XR 2,807,309 9/1957 Saint et al. 272-86 2,899,193 8/1959 Foster 185-37 2,979,734 4/1961 Saint et al. 272-86 3,112,814 12/1963 Pasqua 185-37 3,151,704 10/1964 Clarke 18537 ANTON O. OECHSLE, Primary Examiner.

PAUL E. SHAPIRO, Assistant Examiner.

U.S. Cl. X.R. 185-38; 58123

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