Abstract:
The present invention is an electrically driven open top infant swing comprising a crossbar that does not extend directly over the top of the infant swing. Thus, as opposed to other prior art swing designs utilizing crossbars, the crossbar of the present invention provides excellent stability and rigidity to the swing described and claimed herein while still allowing relatively easy access to an infant seated in the swing seat. Additionally, the present invention provides an infant swing that is coupled to an electric drive motor by a “moving pivot” thereby allowing the swing to pivot independently of the drive motor and thus avoiding undue strain on the swing motor and gearing.

Description:
BACKGROUND OF THE INVENTION 
     The present invention is directed to an infant swing, and more specifically to an open top, electrically driven infant swing which is stable and efficient in operation. 
     In the past there have been many different types of infant swings. In particular, very early on infant swings having an “A” frame configuration were very popular. In a typical swing configuration of this type, the swing structure consisted of two A shaped legs which were attached by a lateral cross bar or axle at the top vertices of the A. The swing itself was generally hung from the cross bar and a motor, usually either spring or electric, was operatively connected thereto to provide the motive force for moving the swing. In these prior configurations, the motor was usually located somewhere on one of the two leg structures, fairly close to the rotational axis of the axle. While this positioning of the motor was generally acceptable, it would be preferred, from a stability standpoint, to position the motor closer to the center of gravity of the swing, at a location generally equidistant from the respective support structures of the swing, namely the A shaped legs. An example of this type of prior art swing is shown in U.S. Pat. No. 5,378,196. 
     While swings of this general configuration have been popular, there are some disadvantages to these types of swings which have been addressed in more recent swing designs. In particular, while these prior art swings which incorporate an axle or crossbar to space the A shaped legs are relatively stable, the axle or crossbar tends to prevent easy access to a child located in the seat hanging therefrom. In order to overcome this problem, most of the newer swing designs tend to be “open top” designs wherein there is no crossbar or axle which runs directly across the top of the support structure over the top of the seat. These newer style “open top” swings allow much easier access to the child than the prior art swings discussed above. Examples of typical “open top” swings include U.S. Pat. No. 5,525,113 owned by Graco Children&#39;s Products, Inc., U.S. Pat. No. 5,769,727 owned by Evenflo Company Inc., and U.S. Pat. No. 5,791,999 owned by Kolcraft Enterprises, Inc. As can be seen in all of these patents, there is no axle or crossbar that extends directly over the top of the swing and stability is provided by attaching the bases of the A shaped legs, rather than the vertices of the A&#39;s as in prior art swings. While these designs have been generally effective, sometimes greater stability and rigidity than can be delivered by a swing structure having no upper crossbar or axle is desired. 
     Most importantly, though, it is noted that most prior art swing designs incorporate motor couplings which are directly linked to the swing itself. This type of design can successfully deliver power to the swing, but has some disadvantages. For example, the direct linkage means that if the swing is stopped or forced in the wrong direction while the motor is engaged, depending on the exact construction of the swing, the gears can be stripped or the motor can be damaged. Additionally, a direct linkage usually results in a swing motion which is rigid and fairly mechanical when it would be preferred to have a swing motion that is smoother and more pendulum like. 
     Accordingly, given some of the above-noted deficiencies of prior art infant swings, it would be desirable to have an infant swing including a support structure that is generally stable and allows easy access to an infant seated in the swing chair. Additionally, it would be desirable to have an infant swing that provides a novel drive and coupling system which efficiently provides a smooth, natural swing motion for an infant seated in the swing. Furthermore, it would be desirable to have a novel drive and coupling system which prevents damage to the swing motor and gear system when the motion of the swing is stopped or modified while the swing is in motion. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an open top infant swing incorporating a novel support structure that is generally stable and allows easy access to an infant seated in the swing seat. Additionally, the present invention provides a novel drive and coupling system for an infant swing which efficiently provides a smooth, natural swing motion for an infant seated in the swing. The novel drive and coupling system of the present invention is additionally characterized in that damage or stress to the swing motor and gear system is generally prevented when the motion of the swing is stopped or modified while the swing is in motion. 
     More specifically, the infant swing of the present invention comprises a novel support structure including a crossbar that does not extend directly over the top of the infant swing. Thus, as opposed to other prior art swing designs utilizing crossbars, the crossbar of the present invention provides excellent stability and rigidity to the infant swing described and claimed herein while still allowing relatively easy access to an infant seated in the swing seat. Preferably, the crossbar structure of the infant swing of the present invention is a relatively rigid hollow molded plastic construction thereby providing room therein for mounting a motor, gear and coupling assembly. Additionally, the present invention provides an infant swing that is coupled to an electric drive motor by a “moving pivot” thereby allowing the swing to pivot independently of the drive motor. The use of a moving pivot in this application prevents undue strain on the motor and gearing of the swing when the swing is stopped or pushed in a direction opposite of the direction of travel being induced by the motor. Additionally, the moving pivot as used in this application is useful in that the movement induced in the swing is more fluid and soothing for the infant riding therein than the movement of prior art swings utilizing direct drive mechanisms. 
     Accordingly, as described above, and as is shown and discussed in detail herein, it is an object of the present invention to provide an improved open top infant swing Other objects and advantages of the present invention will be apparent from the following description and the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front perspective view of an open top infant swing in accordance with the present invention; 
     FIG. 2 is a top perspective view of a connection brace for use with the swing of FIG. 1; 
     FIG. 3 is a front elevational view of the lower housing and swing coupling system of the connection brace of FIG. 2; 
     FIG. 4 is a side elevational view of the lower housing of FIG. 3; 
     FIG. 5 is a top plan view of the lower housing of FIG. 3; 
     FIG. 6 is a bottom perspective view of the motor assembly as shown in the lower housing of FIG. 3; 
     FIG. 7 is a cutaway top perspective view of the motor assembly of FIG. 6; and 
     FIG. 8 is an exploded side perspective view of an alternate embodiment of a connection brace for use with the swing of FIG.  1 . 
    
    
     DETAILED DESCRIPTION 
     As best shown in FIG. 1, the present invention is an open top infant swing  10  incorporating a leg and support structure  12  that is generally stable and allows easy access to an infant seated in the swing seat  14 . In particular, the support structure  12  consists of a front leg component  16 , a rear leg component  18  and a connection brace  20  for connecting the front leg component  16  to the rear leg component  18 . In a preferred embodiment, the leg components  16 ,  18  are constructed of a lightweight tubular metal material, such as aluminum or steel. The leg components  16 ,  18  are preferably provided with feet  22  for contacting a support surface, such as a floor, and stabilizing the swing  10  thereon. Also in a preferred embodiment, the front leg component  16  includes a stabilizing crossbar  24  that extends between the left and the right sides of the front leg component and provides stability and rigidity to the swing support structure  12 . Similarly, the rear leg component  18  is preferably provided with a crossbar  26  that extends between the left and the right sides of the rear leg component  18  for providing additional stability and rigidity to the swing support structure  12 . A seat  28  is provided for supporting an infant and can be of any suitable construction. Preferably the seat  28  is equipped with a detachable tray  30 , a padded seat cushion  32 , a securing harness  34 , and a leg/foot rest  36 . The seat  28  hangs from a pair of support arms  38  that are pivotably attached to the connection brace  20  as will be discussed in further detail below. The support arms  38  can be constructed of any suitable material but are preferably formed of a lightweight tubular metallic material, such as steel or aluminum. 
     As best seen in FIG. 2, the connection brace  20  of the swing support structure  12  may be made of any suitable components and materials, but is preferably made of a two-piece hollow molded plastic construction including receiving areas for the mechanical components of the swing  10 . More particularly, the connection brace  20  preferably comprises an upper housing  40  and a lower housing  42  that are shaped to include a receiving area  44  for housing a motor assembly  46  (see FIGS. 6 and 7) and controls  48  therefor. While the connection brace  20  as shown herein is semi-cylindrical in shape so that it does not cross directly over the top of the seat  28 , thereby allowing easy access to an infant seated therein, it is contemplated that the connection brace  20  could be other shapes, such as rectangular or a parabolic, and these shapes are considered within the scope of the present invention. 
     While many different motor assemblies could be utilized to provide the appropriate motive force for the swing  10 , in a preferred embodiment, as best seen in FIGS. 6 and 7, an electric DC motor  50  is utilized. The motor  50  can be chosen from many suitable prior art designs and is preferably powered by batteries  51  (see FIGS.  3 - 5 ), although the use of AC power in connection with a transformer is also contemplated by the invention. Additionally, the motor is preferably a variable speed motor including a speed control device (not shown) operatively connected to the motor controls  48  for varying the speed of the motor  50 , and thus the speed at which the seat  28  swings. In a preferred embodiment the motor  50  includes a drive axle  52  having a worm gear  54  mounted thereon. The worm gear  54  is operatively coupled to a drive gear  56  having a central axis  58 . An eccentric rod  60  is mounted on the central axis  58  of the drive gear  56  such that when the motor  50  is operated the eccentric rod  60  is rotationally driven producing a circular swing path, the diameter of which is determined by the offset of the eccentric rod  60 . Thus, when the eccentric rod  60  is operatively attached to the coupling system  62  that will be discussed in detail below, and the motor  50  is actuated, the motor  50  drives the swing seat  28  in a lateral swinging motion. 
     As best seen in FIGS. 3-5, the lower housing  42  is shaped to receive the motor assembly  46  as well as the coupling system  62 . As mentioned above, the coupling system  62  is used to couple the motor assembly  46  to the swing seat  28  to provide the motive force for the swing  10 . The coupling system  62  is made up of several components which operate to transfer the rotational force delivered from the motor  50  through the eccentric rod  60  to swing the seat  28 . Specifically, as best seen in FIGS. 5 and 8, a semi-cylindrical drive rod  64 , including ends  65  and mid-point  67 , is positioned in a track  68  in the lower housing  42  connection bracket  20 . A drive bracket  66  is fixedly attached to the drive rod  64  mid-point  67  and the drive bracket  66  includes a slot  70 , preferably rectilinear in shape, formed therein for receiving the eccentric rod  60 . The drive bracket  66  is positioned and attached to the drive rod  64  such that rotation of the eccentric rod  60  in the slot  70  causes the drive rod  64  to oscillate in a linear-horizontal direction in the track  68  with respect to the swing  10 . 
     The ends  65  of the drive rod  64  are attached to pullers  72 . Each puller  72  includes coaxial apertures  74  on either side thereof for receiving a lower pivot axle  76 . The lower pivot axle  76  is a stub axle and is not fixedly attached to the swing support structure  12  thereby providing the “moving pivot” discussed above. The “moving pivot” is attached to the swing support structure  12  by a pivot hanger  78 . The pivot hanger  78  includes coaxially spaced lower apertures  80  for receiving the lower pivot axle  76  and coaxially spaced upper apertures  82  for receiving the upper pivot axle  84 . The upper pivot axle  84  is anchored into the connection brace  20  and allows the pullers  72  to move the swing seat  28  connected thereto. More specifically, the seat  28  has swing arms  38  connected thereto and extending upwardly therefrom which support the seat  28 . The swing arms  38  are fixedly attached into the swing arm sleeves  86  by pins  88  through apertures  90 . The upper ends of the swing arm sleeves  86  include coaxially spaced apertures  94  for receiving the lower pivot axle  76 . Accordingly, the hangers  78  and swing arm sleeves  86  both pivot coaxially around the lower pivot axle  76 . 
     Thus, when the pullers  72  are oscillated backward and forward by the ends  65  of the drive rod  64 , the swing arms  38 , and thus the seat  28  attached thereto, will generally be pivoted roughly about the upper pivot axle  84 . However, since the swing arm sleeves  86  are fixedly attached only to the swing arms  38 , while being pivotably attached to the lower pivot axle  76 , the swing arms  38 , and thus the swing seat  28 , can pivot independently of the upper pivot axle  84 . Accordingly, when motion of the swing seat  28  is stopped or reversed by an outside force, the swing seat  28  can pivot about the lower pivot axle  76  while the pullers  72  are actually pulling (or pushing) the swing arm sleeves  86  in the opposite direction. In this manner, stripping of the motor assembly  46  gears or strain on the motor  50  that would normally occur in such a situation is ameliorated. Furthermore, given that the swing seat  28  is pivoting on not one but two separate axles, the pivoting motion is smoother and more comfortable for an infant seated in the seat  28 . 
     Having described the invention in detail and by reference to the preferred embodiments, it will be apparent that modifications and variations thereof are possible without departing from the scope of the invention.