Portable Child Safety Seat with Five-Point Restraint

Abstract

The present invention combines the benefits of a booster seat with those of a five-point restraint to provide a compact, portable, lightweight car seat with a five-point harness. The invention consists of a seat-bottom and a backplate. It provides simple installment using either LATCH or the vehicle's adult shoulder-lap belt, with infinite height adjustment of the child's shoulder harness anchors requiring only two belt-length adjusters. A criss-cross connection between seat-bottom and backplate reduces excursion and injury in side impacts. A double-loop connector minimizes incorrect installation. The child's harness has been completely rerouted to lower production cost and to reduce misuse of the restraint. The seat cover can be easily removed without the need to replace any belt webbing, and can be used as a storage compartment for the back-plate, five-point harness and tethers. The cover contains handles, such that it can be carried like a tote.

Claims

1. A portable child restraint system configured to attach securely to a vehicle seat and restrain a child's body from significant movement within the restraint system, and further comprising: a back-plate; an upper anchoring assembly; a seat-bottom; a lower anchoring assembly; a five-point harness; and a cover assembly.

2. The portable child restraint system of claim 1, wherein said back-plate: comprises a rigid, trapezoidal extrusion containing a plurality of through hole slots distributed about the front surface designed for specific belt webbing positioning; wherein said through hole slots include two lowermost angled slots, which are used to fasten said back-plate in the location of choice; and two center horizontal slots, which are used to anchor the top of the child's shoulder straps; and two uppermost slots, which are used to anchor the top of said back-plate to the vehicle seat; and wherein said back-plate comprises the means to rigidly secure and maintain the shoulder harness anchors in the optimal position.

3. The portable child restraint system of claim 1, wherein said upper anchor assembly: comprises an anchor tether of a single belt loop extending vertically from the back-plate of claim 1 through a belt length adjuster and an anchor hook for attachment to an attachment point at or near the top of a seat back in a vehicle; wherein said single belt loop may be routed around the head restraint of the vehicle seat back or through the opening between an adjustable head restraint and the top of the vehicle seat back to an attachment point at or near the top of a seat back; and wherein the upper anchor assembly allows for infinite height adjustment of the shoulder harness anchors of the back-plate of claim 2.

4. The portable child restraint system of claim 1, wherein the back-plate of claim 2 is connected to the seat-bottom by a crisscross pattern of webbing that prevents lateral movement of the device during side impacts.

5. The crisscross device of claim 4, further comprising a double-loop-connector: wherein said double-loop-connector comprises two webbing loops fastened perpendicular to one another; wherein each portion of the crisscross pattern of webbing of claim 4 is threaded through one of the webbing loops of said double-loop-connector; wherein said double-loop-connector holds the crisscross pattern of webbing in place so that said crisscross remains configured correctly at all times relative to the position of the back-plate of claim 2 and regardless of the length of the child's shoulder straps; wherein said double-loop-connector allows adjustment of the length of the crisscross pattern of webbing without altering the crisscross configuration.

6. The criss-cross device of claim 4, further comprising a lower anchoring assembly attached to the seat-bottom of claim 1: wherein said lower anchoring assembly comprises the opposing ends of the crisscross pattern of webbing, each of which passes through either a lower anchor hook or a D-ring attached to the lower anchor hook at both rear corners of the seat-bottom of claim 1; wherein at least one side of said webbing of the lower anchoring assembly, after passing through either a lower anchor hook or a D-ring at the corners, is fed through a belt length adjuster; wherein said belt length adjuster may attach to either webbing member of the lower anchoring assembly or, for convenience, two belt length adjusters may attach to both webbing members at the corners of the seat-bottom; and wherein said webbing, after passing through either or both belt length adjustors, is permanently coupled or fastened to the opposite corners of the seat-bottom as far up and forward as the armrest and side of the seat-bottom allow.

7. The lower anchoring assembly of claim 6: wherein said lower anchoring assembly tightly secures the seat-bottom of claim 1 to the vehicle-seat; wherein said lower anchoring assembly, in conjunction with the upper anchoring assembly of claim 3, tightly secures the back-plate of claim 2 to the vehicle seat; wherein said lower anchoring assembly, in conjunction with the upper anchoring assembly of claim 1, adjusts the height of the back-plate of claim 2; and wherein the foregoing adjustments in this claim 7 may be accomplished using a single belt length adjuster located at either or both lower corners of the seat-bottom of claim 1.

8. The portable child restraint system of claim 1, wherein said seat-bottom is independent from, and not rigidly fixed to, the back-plate of claim 2.

9. The seat-bottom of claim 8, further comprising: anchor-hooks located at the underside of each lower corner of the seat-bottom, wherein said lower anchor-hooks are each permanently coupled to the seat-bottom at the end of short, flexible straps or tethers; said straps extend horizontally from the back of the seat-bottom, allowing the lower anchor-hooks to attach to an attachment point at or near the bottom of an adult seat back in a vehicle and tightly secure the seat-bottom to the vehicle seat;

10. The lower anchor-hooks of claim 9, further comprising: a D-ring coupled to each of the lower anchor-hooks; said D-rings are used to thread the end of each belt portion of the criss-cross device of claim 3, which then passes through a seat-belt length adjuster and affixes to each side of said seat-bottom with the lower anchoring assembly of claim 6; said D-rings further allowing the lower anchoring assembly of claim 6 to securely attach to the lower anchor-hooks of claim 9 and secure the portable child restraint system to the vehicle seat.

11. The seat-bottom of claim 8, further comprising an armrest on each side extending vertically from the top of the seat-bottom, each of which is angled rearward and in constant contact with the vehicle seat as to prevent upward tipping of the seat-bottom;

12. The seat-bottom of claim 8, further enabling introduction and placement of the child's buckle and hip straps using a plurality of through-holes, wherein said through-holes include: a single slot near the left and one near the right armrest, which are used to route the hip portion of the five point harness of claim 13; a plurality of slots distributed along the centerline of the seat-bottom of claim 8, which are used to attach the groin buckle; and a single slot centered in the foremost portion of said seat-bottom of claim 8, through which a harness-length adjuster strap is routed and locked into position.

13. The portable child restraint system of claim 1, wherein said five-point harness employs a reconfigured routing method originating at the top of the back-plate of claim 2, which reduces the length of the harness webbing, prevents entanglement and incorrect routing of the harness webbing, and eliminates the need for harness end loops and adjustment clip, which are found in typical car seats.

14. The five-point harness of claim 13 and its reconfigured routing method, having an upper portion and a lower portion, wherein: the upper portion comprises a single belt originating from rear of one of the center, horizontal through holes in the back-plate of claim 2, and looping through one of the buckle's latch plates, then into the seat-bottom at one of the hip slots, along the underside of the seat-bottom of claim 8, up through the other hip slot, back through the other latch plate and terminating again through the other center horizontal through hole in the back-plate of claim 2; and the lower portion comprises a buckle anchored to the center of the seat-bottom of claim 8, using one of the center slots in the seat-bottom of claim 12, to receive the latch plate the lower portion further comprises a single adjuster strap, which is permanently affixed to, and originates from, the center of the belt portion underneath the seat-bottom and is threaded through the belt adjuster slot at the front of the seat-bottom, allowing the adjuster strap to be pulled to tighten and constrict the child's harness.

15. The portable child restraint system of claim 1, wherein the seat cover assembly comprises a back-plate cover and a seat-bottom cover, both of which are removable without disengagement of tethers or harness webbing.

16. The seat cover assembly of claim 15, further comprising: a partially cushioned/padded piece of fabric shaped to the size of the back-plate of claim 2 with Velcro or zipper-like edgings so as to cover the whole component, front with padded cover and back unpadded, with slits into the fabric from the edges of all through slots to the edge of the fabric to ensure the cover may be removed without disengaging any of the belts; and a cushioned/padded fabric shaped to cover the top surface ranging from the rear end over the front contoured portion of the seat-bottom of claim 8; which fabric continues padded or unpadded along the underside back to the rear; and which top and bottom coverings are connected together at the sides, with a slit sufficiently wide to enable the buckle to pass through, while the rear end of the top and bottom contains a Velcro or zipper-like coupling to ensure that the cover may be quickly removed without disengaging the belts.

17. The seat cover assembly of claim 15, wherein said seat-bottom cover may be utilized as a storage compartment for the back-plate, harness and tethers by opening the rear-end coupling and inserting said back-plate, harness and tethers, and which further comprises a plurality of handles or a shoulder strap connected to one or more of the outer edges of the fabric cover of the seat-bottom to allow the invention to implement a carrying case after storage of the back-plate, harness and tethers into the seat-bottom opening.

18. A method for stowing and transporting a portable child safety seat with five-point restraint, said portable child safety seat having a seat-bottom cover that may be utilized as a storage compartment for the back-plate, harness and tethers of the portable child safety seat and a plurality of handles or a shoulder strap connected to one or more of the outer edges of the fabric cover of the seat-bottom, comprising the steps of: opening the rear-end coupling of the seat-bottom cover; inserting the back-plate, harness and tethers of the portable child safety seat into the rear-end coupling of the seat-bottom cover wherein said back-plate, harness and tethers are stowed inside of said seat-bottom cover; lifting the portable child safety seat in its stowed position by at least one of the plurality of handles or shoulder strap connected to one or more of the outer edges of the fabric cover of the seat-bottom.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 is a perspective view of the present invention in the installed stage without a cover in cars equipped with a LATCH system;

[0022] FIG. 2 is a perspective view of the present invention in the installed stage with a cover in cars equipped with a LATCH system;

[0023] FIG. 3 is a front view of the present invention in the installed stage in cars equipped with a LATCH system;

[0024] FIG. 4 is an exploded view of the present invention for cars equipped with a LATCH system;

[0025] FIG. 5 is a perspective view of the present invention for cars equipped with a LATCH system;

[0026] FIG. 6 is a front view of the present invention for cars equipped with a LATCH system;

[0027] FIG. 7 is a rear-side view of the present invention for cars equipped with a LATCH system;

[0028] FIG. 8 is a perspective view of the installing procedure for the bottom seat for cars equipped with a LATCH system;

[0029] FIG. 9 is a front view of the back-plate component;

[0030] FIG. 10 is a bottom view of the seat-bottom, depicting the lower part of the harness system and lower hook attachments for cars equipped with a LATCH system;

[0031] FIG. 11 is an isometric view from the bottom of the seat-bottom, depicting the lower part of the harness system and lower hook attachments for cars equipped with a LATCH system;

[0032] FIG. 12 is a right-side view of the present invention, depicting the implementation of a carrying case;

[0033] FIG. 13 is a perspective view of the present invention;

[0034] FIG. 14 is a rear perspective view of the present invention depicting the alternative anchoring system for the back-plate component for cars without a LATCH system;

[0035] FIG. 15 is a rear view of the present invention installed in a car seat without a LATCH system; and

[0036] FIG. 16 is a top view of the seat-bottom component of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0037] All illustrations of the drawings are for the purpose of describing selected versions of the present invention and are not intended to be exhaustive or limit the scope of the present invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may use their teachings.

[0038] The present invention is a passenger restraining system designed to restrain and protect children in an automobile during collisions. The present invention combines the safety of a five-point belt system of regular car seats for children, with the ease of use, portability, and adjustability of booster seats.

[0039] Referring to FIG. 1 a preferred embodiment of the present invention comprises a back-plate, an upper anchoring assembly, a seat-bottom, a lower anchoring assembly, a five-point harness, and a cover assembly. All webbing and belts utilized in the present invention comprise a strong fabric woven into a flat strip deemed appropriate for safety use in high speed vehicles such as automobiles; although, material composition, size, and color of the belts is subject to change in the final embodiment. The back-plate component is designed to allow the user to freely adjust and secure the shoulder straps to the correct height for the child; this is essential, as improper height positioning of the shoulder straps will result in ineffective restraint of the child and may lead to injury or death during vehicle collisions.

[0040] The back-plate comprises a trapezoidal extrusion of a certain thickness with rounded corners; the trapezoid is sized to correctly position a child's shoulder belt anchors and prevent forward and side movement of the back-plate. The back-plate may come in a variety of sizes, and may have additional padding and other accessories for head and thorax protection, or to provide cushioning for a sleeping child. The back-plate contains a plurality of through-hole slots distributed about the front surface as seen in FIG. 9. Each slot is designed for specific belt webbing positioning. The uppermost outboard, in the preferred embodiment, vertical slots in combination with the two lowermost angled slots are used to fasten the back-plate in the location of choice, while the horizontal slots between the two vertical, outboard slots are used to anchor the top of the child's shoulder straps. Using the top outboard and bottom slots as described above, the back-plate is positioned by two tethers. The uppermost outboard vertical slots may also be horizontally positioned.

[0041] First, a top tether, consisting of a single belt, originates from a belt length adjuster, from which it is threaded through the anchor hook opening. It continues to the front of the back-plate, where it passes from the front through the right outboard vertical slot, is routed along the rear of the back-plate, passes back to the front through the left outboard vertical slot, and finishes by threading through the same belt length adjuster it originated from.

[0042] Second, a bottom tether which also consists of a single piece of webbing originates with a fixed attachment from a point near the left rear corner of the seat-bottom, preferably as far up and forward as the armrest and side of the seat-bottom allows. The webbing may be coupled to the left rear corner of the seat-bottom by any suitable means, such as for example, without limitation, by rivet, screw, cement, tack, slot and spindle, snap, hook and loop, zipper, button, melting, tongue and buckle. The bottom tether is then threaded through the opening of the anchor hook directly, or through a D shaped ring of certain thickness attached to the anchor hook, after which it continues through one loop of a double-loop-connector, then through the front of the right lower slot on the back-plate, continues along the rear of the back-plate, is threaded back to the front through the left bottom slot of the back-plate, crosses back over itself through a perpendicular loop of the double-loop-connector, passes through the right lower anchor-hook or a D-ring attached to the anchor-hook, and, finally, is threaded through a belt-length adjuster, which in turn is fixed to the seat-bottom near the right rear corner as in FIG. 14 and FIG. 7. The webbing may, again, be coupled to the right rear corner of the seat-bottom by any suitable means, such as for example, without limitation, by rivet, screw, cement, tack, slot and spindle, snap, hook and loop, zipper, button, melting, tongue and buckle. In their preferred embodiment, the D-rings are tie down rings shaped like a letter D or O, although their precise geometry, weight, finish and load may vary in the final embodiment, and fashioned from lightweight metallic material, such as, without limitation, aluminum, but may be fashioned from any rigid plastic, metallic, non-metallic or composite material. The D-rings may be coupled to the lower anchor-hooks bottom by any suitable means, such as for example, without limitation, by rivet, screw, cement, tack, slot and spindle, snap, hook and loop, zipper, button, melting, tongue and buckle, or other suitable connector. The bottom belt length adjuster may be on the right, the left or on both sides, to accommodate the use in either the left or right seating position.

[0043] The top tether loop is routed from the vertical outboard slots in the back-plate around any head restraint or through the opening between an adjustable headrest and the top of the adult seat back, and locked onto either the top anchor of the LATCH system as in FIG. 4, or to the shoulder belt portion of the seat's three-point adult belt, when routed behind the adult seat back as shown in FIG. 15. The bottom tether's left and right endings are threaded through the corresponding seat-bottom's latching hooks with D-Rings, after which one of the endings continues to a fixture near the rear outside corner of the seat-bottom (one of the sides), while the other passes through a belt length adjuster before being fixed near the rear side corner of the seat-bottom (the other side), as depicted in FIG. 7 and FIG. 8. Another embodiment may include belt length adjusters on either side of the seat-bottom. The top tether loop and the bottom tether each contain a belt length adjuster (see FIG. 7), allowing for harness anchor height adjustment and tight installation of the back-plate and seat-bottom by adjustment of only these two tether lengths.

[0044] There are two horizontally coincidental slots approximately between the two vertical top-tether slots, one on either side an equal distance from the center line, which are utilized for the shoulder straps that run down either side of the child.

[0045] Near the lowermost left and right corner of the back-plate are two angled slot cutouts, in the preferred embodiment the angle is forty five degrees as seen in FIG. 9. The bottom tether webbing is used to anchor the seat-bottom to the adult vehicle seat, and after continuing in a criss-cross pattern using the double-loop-connector, is fed through these slots as seen in FIG. 14.

[0046] In its preferred embodiment, the back-plate comprises a rigid plastic material; other possible material compositions include, but are not limited to light aluminum, light steel, composites, and other comparable materials. The size, geometric design, thickness, and material composition of the back-plate are subject to change in the final embodiment of the present invention.

[0047] The seat-bottom comprises a rectangular extrusion of a certain length and width which enables introduction and placement of the child's buckle and hip straps. In its preferred embodiment, seat-bottom is fashioned from plastic, but may be fashioned from any rigid plastic, metallic, non-metallic or composite material. The seat-bottom may further contain a plurality of and varying indentations and recesses to reduce weight and increase comfort. Looking from the side perspective, the front edge is fully rounded to provide the child an ergonomic surface to rest their legs, as in FIG. 12. Cup holders may be inserted into the front corner position(s). Protruding from the top surface, on either side edge of the component, are two armrests as seen in FIG. 5. The armrests' vertical portion is angled slightly rearward to ensure contact of the top of the armrests with the adult seat back, preventing upward tipping of the seat-bottom during certain accident events. The armrests protrude forward from the left and right corner of the back region of the seat-bottom. In the preferred embodiment, the armrests are L-shaped. The armrests may comprise a strong, rigid material, and may be covered in a soft padding for contact with the child's arm.

[0048] Distributed about the top surface of the seat-bottom is a plurality of slot holes. Similar to the back-plate, each slot hole is designed for a different belt webbing. Looking from the top perspective, there is a single slot near the left and one near the right armrest orientated along the length of the armrest as seen in FIG. 16, the left and right hip slots; distributed along the centerline is a plurality of slots orientated perpendicular to the length of the component, the groin slots. In the preferred embodiment, there are two slots in the middle of the component, the first and second groin slot. The groin belt webbing is threaded through either of these slots, depending on the size of the child. There is one additional slot located on the center front of the component, straight through the curved front edge as seen in FIG. 5; the child's belt adjuster slot is located towards the center. The adjuster slot restricts the movement of the belt length adjuster strap, which is threaded through it in some fashion, preventing slack in the car-seat installation or the child's seat belt system. This locking feature may be achieved through the use of a belt adjuster, a pivot slot with a release button, a locking slot with a release button, or any other comparable means. The seat-bottom may be connected to the vehicle seat by anchor-hooks which are fixed to the rear lower corners of the seat-bottom in some fashion. The location, shape and length of the anchor-hooks may vary to provide secure and tight installation of the seat-bottom. In the preferred embodiment, the hooks are fixed to the rear corners of the seat-bottom's underside with short straps as shown in FIG. 11. The seat-bottom is attached to the vehicle seat by connecting the hooks to the lower anchors of the seat's LATCH system as depicted in FIG. 8. The bottom tether, with its belt length adjuster, is applied to ensure a tight installation of the seat-bottom to the vehicle seat, in addition to aiding in the height adjustment and tight installation of the back-plate.

[0049] The five-point harness comprises a buckle assembly, a harness consisting of one single belt threaded through a plurality of slots on the seat-bottom, buckles, and the back-plate, multiple belt guides, and a harness tie or belt clip. The buckled harness restrains and protects the child during vehicle collisions. The buckle assembly comprises a left latch plate, right latch plate, and a buckle which is placed into one of the groin slots. The left latch plate and right latch plate contain a slot for the belt. The buckle contains a receptive cavity for the left and right latch plate. The buckle locks the latch plate components; the latch plates may be released with the press of a button on the buckle. As shown in FIG. 5, the belt portion consists of one piece of belt webbing threaded from the underside of the seat-bottom through the left and right hip slots, the left and right portions of the webbing then continue upward through the corresponding buckle slots to be anchored through the shoulder slots on the back-plate. The belt portion underneath the seat-bottom is connected perpendicularly to the adjuster strap which in turn is threaded through the belt adjuster slot of the seat-bottom. The configuration and belt threading is seen in FIG. 5 and FIG. 11. Pulling on the adjuster strap will tighten and constrict the child's harness which will ensure a tight, snug fit around the child, which in turn is essential for proper functioning of the restraint in vehicular accidents. The buckle design, locking mechanism, receptive cavities, material composition, and size are subject to change in the final embodiment of the present invention. Additionally, the left and right shoulder straps may contain a plurality of three-bar slides, tilt lock adjusters, belt guides, padded cushions, and other belt accessories which would increase the comfort level of the child. In the preferred embodiment, the left and right shoulder straps contain a belt clip consisting of two belt guides that are horizontally attached via female-male system similar to a quick release buckle.

[0050] The present invention may be attached to the vehicle's car seat in two main ways; using the adult safety belt of the vehicle's seat, or using the LATCH system that comes standard with all newer vehicles. If the car is equipped with the LATCH system, it is best to utilize the associated attaching mechanism. If the car is not equipped with the LATCH system, the adult safety belt of the seat should be utilized to secure the present invention.

[0051] To attach the back-plate to the adult vehicle seat, two different tethers are used, the upper anchor tether loop and the lower anchor tether. The upper anchor tether consists of a single belt which is looped around, originating from a belt length adjuster, which is then threaded through the anchor hook, and continues for a certain length before entering one of the vertical outboard slots from the front, continues along the rear portion of the back-plate, passes through the other vertical outboard slot from back to front, and finishes, after a certain length being threaded through the same belt length adjuster. This loop may be routed around the head restraint or through the opening between the adjustable head restraint and the top of vehicle seat back to the attachment point at or near the top of the vehicle's seat back.

[0052] Referring to FIG. 4, if the vehicle is equipped with the LATCH system, the anchor hook couples to the upper tether anchoring element of the LATCH system. The location of the anchoring element depends on the vehicle, and may vary from the rear side of the vehicle's seat back, to the vehicle's rear wall, or the floor directly behind the vehicle seat. In the absence of the LATCH system, the top tether loop contains (instead of, or in addition to the anchor hook) a belt-locking element which attaches to the shoulder portion of the existing adult safety belt of the vehicle's seat, which is positioned and locked in place behind the seat back as depicted in FIG. 13 and FIG. 15.

[0053] The lower tether is threaded through the lower left and right angled slots of the back-plate and crisscrosses itself using a double-loop connector as described previously. The left and right bottom ends are threaded through either the anchor hooks themselves, or through D-rings attached to the seat-bottom anchor-hooks at both rear corners, then fastened to either side of the seat-bottom as depicted in FIG. 7 and FIG. 14. At least one of said bottom ends is threaded through a belt length adjuster before attaching to the side of the seat-bottom as seen in FIG. 7. The top tether loop's belt length adjuster is in close proximity to the belt hook; it adjusts the height of the back-plate and the harness anchors. Furthermore, it provides tight installation of the back-plate in conjunction with the lower tether, which minimizes movement of the back-plate with its shoulder strap anchors to provide optimal protection for the child. Minimal movement of the back-plate is needed to provide optimal protection for the child in a wide range of accident events. Using both top and lower tethers, the shoulder anchors may be positioned at any height of choice.

[0054] When equipped with the LATCH system, the seat-bottom is connected to the motor vehicle by fastening the seat-bottom anchor hooks to the lower LATCH anchors of the vehicle seat, and tightening the lower tether with the belt length adjuster as shown in FIG. 7 and FIG. 8. In the absence of the LATCH system, the seat-bottom component is fastened to the vehicle seat by threading the lap portion of the adult safety belt under the armrests as seen in FIG. 13. The shoulder portion of the adult safety belt is routed behind the vehicle's seat back and used to hold the back-plate in place via the top tether loop with a belt-locking clip.

[0055] The cover assembly comprises a back-plate cover and a seat-bottom cover. The back-plate cover comprises a partially cushioned/padded envelope of flexible cloth or other suitable material shaped to the size of the back-plate with Velcro or zipper-like edgings so as to cover the whole component. The front, or child-facing side, of the cover includes padding (e.g., foam, batting and gel) while the back remains unpadded. Slits are provided into the fabric from the edges of all slots to the edge of the fabric as shown in FIG. 2 to ensure the cover may be removed without disengaging any of the seat belts. The seat-bottom cover is similar to the back-plate cover; the cushioned/padded fabric is shaped to cover the top and side surfaces ranging from the rear end over the front contoured portion of the seat-bottom. The fabric continues unpadded along the underside back to the rear. Velcro or zipper-like couplings are located at the back end to ensure that the cover may be quickly removed without disengaging the seatbelts. The back end Velcro or zipper-like coupling may be utilized as a storage compartment for the back-plate as seen in FIG. 12. A plurality of handles or a shoulder strap may be connected to the fabric cover near the back coupling to allow the invention to implement a carrying case after storage of the back-plate into the seat-bottom opening.

[0056] Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as herein described. This application is, therefore, intended to cover any variations, uses or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice within the art to which this disclosure pertains.