Abstract:
A seat belt locking clip, in accordance with the preferred embodiment of the present invention, prevents relative movement of the lap and shoulder portions of a typical automotive seat belt system with respect to the buckle, thereby maintaining seat belt tension. Of one piece construction, the clip consists of a main body having a centrally located handle for positioning and applying rotary force during installation, and a plurality of finger extensions on opposing sides to reach under and retain the belt portions. The clip can also include raised projections on the finger extensions.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention is directed in general to an improvement in a common device for securing a child seat in a passenger vehicle, more specifically to a seat belt locking clip that is used to prevent relative movement of the shoulder and lap portions of the vehicle seat belt which results in loss of the belt tension that holds the child seat secure.  
         BACKGROUND OF THE INVENTION  
         [0002]    When a child rides in a motor vehicle, the law normally requires that the child must be in an approved car seat for that child&#39;s weight class. Most child seats are secured to the vehicle&#39;s seat by the seat belt for that particular seating position in the vehicle. The common method involves threading the latch plate end of the seat belt through a provided path in the lower back of the child seat and inserting it into the receiver. With a lap belt only seat belt, tension is achieved by ratcheting the feed side of the belt back into its retractor. With the more common combination lap and shoulder type belt, no ratcheting feature is present. The latch plate slides freely on the shoulder/lap portion of the seat belt, with only modest tension supplied at all times by the retractor at the shoulder end. The belt is locked with an inertial type stopper that only activates during times of acceleration or deceleration. Therefore, another device for locking the belt must be employed to lock the belt length, and thus maintain the tension required for a secure mounting of the child seat.  
           [0003]    There has been much discussion in the media, consumer-testing organizations, web sites, etc. regarding proper installation of child car seats. Most recommend that the seat belt tension be quite significant, such that the top end of the child seat can be moved/offset/wiggled less than an inch with a forceful adult push. The National Highway Traffic Safety Administration (NHTSA) estimates that 80% of all child seats are improperly installed in some way, and by far, the most common installation error is that the child seat is loose due to insufficient seat belt tension.  
           [0004]    Many manufacturers of child car seats supply with each unit a seat belt locking clip  2  of generic design, as shown in FIG. 1. Typical instructions for installing this clip ask the user to install the seat belt thru the back of the car seat, tension the belt by pulling on the shoulder portion, holding the two pieces of the belt together at or near the latch plate, releasing the latch plate from the receiver, and installing the clip to fasten the two belts together. Then, the latch plate is reinserted into the receiver. On some car seat/seatbelt combinations this is indeed possible. On many vehicles, however, the receiver end of the seatbelt is extended from the car seat a few inches, which results in a location behind, or nearly behind, the back of the child car seat when the car seat is installed. This makes the latch plate inaccessible for reinsertion into the receiver after clip installation. A typical installer then realizes that the clip has to be installed on the shoulder belt side of the seat, while holding tension on the belt. The generic clip  2 , by its design, requires that the belts be somewhat folded lengthwise so that each portion can be inserted into the reception spaces  4  of the clip on the first side, and then again upon insertion into the second side. The difficulty in performing this operation increases proportionately with the tension in the belts, and is very difficult to do while maintaining significant tension on the shoulder part of the seat belt with one hand. Frequently, tension in the seat belt is gradually lost while these manipulations occur, resulting in the situations described in the NHTSA reports. If the car seat is left in the loosely installed condition, the injury prevention capacity of the car seat is reduced in a vehicle collision.  
           [0005]    Therefore, there is a need to provide a device for securing the shoulder and lap portions of the seatbelts while under tension, and with the speed and ease of a one hand operation.  
         SUMMARY OF THE INVENTION  
         [0006]    The present invention satisfies the herebefore unsolved need. The present invention provides an improved device for securing a child seat to a vehicle seat using a contemporary seat belt system factory installed in the vehicle, and more particularly to the construction and use of an improved seat belt locking clip to prevent loss of seat belt tension. A seat belt locking clip which prevents relative movement of the lap and shoulder portions of a typical automotive seat belt system with respect to the buckle, thereby maintaining seat belt tension is described. Of one piece construction, the clip consists of a main body having a centrally located handle for positioning and applying rotary force during installation, and a plurality of finger extensions on opposing sides to reach under and retain the belt portions. Additionally, in accordance with principles of the present invention, the locking clip can include raised projections in the fingers to prevent removal of the clip in a rotary manner opposite that of installation. The seat belt must be unbuckled to remove tension in the belt before the clip can be removed.  
           [0007]    Another object of the invention is to provide for single-handed operation. Significant tension in the seat belt must be achieved if a secure installation of the car seat is to result. The locking clip of the present invention is installed with the manipulation of the clip requiring the use of only one hand, which leaves the other free to maintain the belt system tension by force applied to the shoulder portion of seat belt. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    Other features and advantages of the invention, both as to its structure and its operation, will best be understood and appreciated by those of ordinary skill in the art upon consideration of the following detailed description, appended claims and accompanying drawings of preferred embodiments, in which:  
         [0009]    [0009]FIG. 1 shows a prior art locking clip;  
         [0010]    [0010]FIG. 2 shows a perspective view of the locking clip on a portion of a belt, according to principles of the present invention;  
         [0011]    [0011]FIG. 3 shows an alternative version of the locking clip having raised projections in the surface of the finger extensions;  
         [0012]    [0012]FIG. 4 illustrates a perspective view of a typical child seat installed using the present invention to lock the tension into a typical lap and shoulder seat belt system; and  
         [0013]    [0013]FIGS. 5 a - 5   c  illustrate installation of the locking clip having principles of the present invention on a vehicle seat belt. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0014]    Referring to FIG. 2, a seat belt locking clip  100  in accordance with a preferred embodiment of the invention includes, among other elements, an essentially flat main body portion  10 , a handle portion  20  and two fingerlike extensions  30  connected to opposing sides of the main body  10 . The main body  10  forms a central frame on which is positioned the handle portion  20 . Two fingerlike extensions  30  are located on opposite sides of the main body  10 , and extend across the width of the main body  10  in opposite orientation to each other as shown. The fingers are parallel to the main body edges and spaced away from it an appropriate amount to form belt-receiving slots  40 . The belt-receiving slots  40  should be sized to accommodate the thickness of the flat belts, such that the belts can be inserted into the slot with adequate clearance. The locking clip  100  is sized such that the belt receiving slots  40  have a length matched to the width of the belts that it will be installed on. As illustrated in the figure, the ends of the fingers can be formed in an arcuate or bent manner such that the upper surface of the tip of the finger will be below the lower surface of the main body  10  by an amount to accommodate two seat belt thicknesses. In the preferred embodiment, the handle  20  and finger extensions  30  are shown as being integral with the main body portion  10 . However, in alternative embodiments, the handle portion  20  could be constructed as a separate piece and attached to the main body  10  in a suitable manner. Similarly, the fingerlike extensions  30  could be constructed separately and attached to the main body  10 . As discussed above, the present invention is preferably formed as a single integral unit, which can be manufactured in a cost efficient manner. The locking clip  100  is preferably constructed from steel, or other hard materials having suitable strength and stiffness, and can be machine cut, stamped or cast out of the chosen material.  
         [0015]    Referring now to FIG. 3, an alternative embodiment of the locking clip  100 , according to principles of the present invention is shown. In this embodiment, the fingerlike extensions  30  include raised projections  50  on the surface of the finger. Preferably, the raised projections  50  emanate from the surface of said fingers  30  in a slanted and directional manner so as to permit a seat belt in intimate contact to pass over them in one direction while restraining movement in the essentially opposite direction. The raised projections  50  have, on one side, a nominally smooth ramp profile at an angle that permits the seat belt to slide up and over to pass the projection in the “forward” direction, and, on the other side, a near vertical wall to prevent the seat belt from passing when approached in the “reverse” direction. The tip of the projection is nominally pointed to facilitate entry into the weave of the seat belt fabric to assist in preventing movement of the belt in the “reverse” direction. Thus, the orientation of the raised projections is such that the projections are permitted to slide under the surface of the belt during installation of the clip  100 , but retard movement of the clip  100  in the opposite direction, for example, as if attempting to remove the clip by turning in a rotary direction opposite that of the installation direction, while the seat belt is under tension. This feature prevents removal of the clip by the child seat occupant as well as from vehicle vibration or impact. Only when the seat belt is unbuckled, resulting in removal of tension in the belts, may the clip be easily disengaged from the belt and removed. The locations of the raised projections  50  in the surface of the fingers  30  is shown proximate to the base of the finger extensions  30 . However, the raised projections  50  can be positioned in other locations on the surface of the fingers  30 . Additionally, the finger extensions  30  can include multiple sets of raised projections  50 .  
         [0016]    Utilization of a locking clip in accordance with principles of the present invention is shown in FIGS. 4 and 5 a - c . FIG. 4 illustrates a perspective view of a typical child seat installed using the present invention to lock the tension into a typical lap and shoulder seat belt system. A child seat  60  is mounted onto a vehicle seat  62  using the seat belt system supplied with the vehicle. The seat belt latch plate (not shown) is routed through the passageway  64  in the rear of the child seat  60  and engaged in the receiver. The lap portion  66  of the seatbelt extends from the buckle to the vehicle floor or frame for secure attachment. This same belt extends through the latch plate and returns through said passageway as the shoulder portion  68  of the seat belt system. The seat belt locking clip  100  is shown in the installed position (see exploded view) wherein its function is to prevent the portion of the shoulder belt  68  from the locking clip  100  to the buckle from moving with respect to the lap belt  66 . This is accomplished by securely forcing the two belts into intimate contact through a circuitous path through the clip  100 .  
         [0017]    Turning now to FIGS. 5 a - 5   c , installation of the locking clip  100  on a seat belt securing a child car seat  60  will be described. FIG. 5 a  illustrates the initial positioning of the locking clip  100  on the seat belt portions  66 ,  68 . After tensioning the seat belt by pulling on the shoulder portion  68 , the upper finger  30  is partially engaged under both seat belt portions  66 ,  68  by manipulating the clip in the direction of arrow A. The design of the preferred embodiment of the locking clip  100  is essentially symmetrical in a rotary sense, in that the fingers  30  are in a proper orientation to begin installation regardless of which orientation the clip  100  is in when the user initially grips the handle portion  20 . Similarly, the lower finger  30  may be partially installed first, according to installer preference.  
         [0018]    [0018]FIG. 5 b  illustrates the secondary positioning of the locking clip  100 , showing the engagement of a second finger  30  under the seat belt portions  66 ,  68 . This is accomplished by forcing the base portion of the clip against the surface of the belts, rotating the clip  100  in a counter clockwise manner as indicated by arrow B, until the tip of the second finger  30  passes the edge of the belts. Then the rotational motion of the clip  100  is reversed to engage the tip of the second finger  30  under both portions of the seatbelt  66 ,  68 .  
         [0019]    [0019]FIG. 5 c  illustrates the final rotational manipulation of the locking clip  100  into its fully installed position. The rotational motion of the clip  100  continues in the direction of arrow C until the edges of the seatbelts  66 ,  68  are fully inserted into both the upper and lower belt-receiving slots  40 . In this position, the raised projections  50  on the fingers  30  have engaged the lower surface of the belt pair, and are preventing the clip  100  from being removed by application of a rotary force in a direction opposite to that of installation.  
         [0020]    Having thus described an embodiment of the invention, it will now be appreciated that the objects of the invention have been fully achieved, and it will be understood by those skilled in the art that many changes and widely differing embodiments and applications of the invention will suggest themselves without departure from the spirit and scope of the invention. Among them, but not limited to, are construction from multiple parts, alternate finger profiles and lengths, alternate finger tip bending profiles, mirror imaging for changing clockwise installation to counter clockwise installation, alternate handle shape and orientation, alternate projection profiles, numbers, and locations, handle deletion, and provision for accepting a separate tool for application of rotary motion. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.