Most grocery stores, supermarkets, and other large retail outlets provide shopping carts for their customers. These shopping carts typically have a seat within the cart which is designed to hold small children, typically children 5 years of age or younger. Such child seats are very convenient for a shopper with a small child, however they are also inherently dangerous due to the high location of the seat. Young children of this age are naturally very active and curious and there are lots of distractions in a store for both the child and the adult who is preoccupied with shopping. Unfortunately, this combination can lead to serious injury to the child if he or she falls out of the child seat. Another potential hazard presented by seating a child in a high location on a cart with a narrow wheel base is that the cart is relatively unstable and can be tipped over rather easily, e.g., by an older sibling hanging onto the side of the cart. Once again, the high location of the child seat also increases the likelihood that a serious injury may result from such a tip over.
The United States Consumer Product Safety Commission (CPSC) has estimated that an average of 20,400 children 5 years old and younger were treated in hospital emergency rooms in the United States each year from 1985 through 1994 for injuries relating to shopping carts 1!. This estimate was based on incidents reported through the National Electronic Surveillance System (NEISS) during this time period, which also showed that the highest number of injuries (56%) associated with shopping carts in this age group was falls. Approximately 75% of the injuries due to falls were cuts, scrapes, and bruises; however, concussions represented about 20% of other injuries and 5% were fractures which required hospitalization. The other major causes of shopping cart-related injuries for this age group identified by the NEISS reports were "contact/run-into carts" (19%) and "tipovers")(8%) 1!. (A separate study concluded that after falls, tipovers are the second most common mechanism of shopping cart-related injuries among children younger than two years of age that were treated in emergency rooms 2!.) In both falls and tipovers the risk of serious injury is exacerbated by the relatively high location of the child seat in the conventional shopping cart, i.e., the child has a long distance to fall and the cart is more likely to tip over due to the high center of gravity.
This inherently dangerous situation has been recognized for some time and has been addressed by others. Most of the prior art consists of harnesses and/or collapsible structures that are attached to the existing child seat in a conventional shopping cart (e.g., U.S. Pat. Nos. 4,108,489; 4,204,695; 4,867,464; and 5,641,200). However, all of these proposed solutions require additional equipment that the shopper must: 1) purchase, 2) remember to bring with him or her to the store, 3) learn how to operate, and 4) take the time to use on each visit. Of course, such equipment could also be permanently attached to the carts or loaned by the stores to their customers with small children; but, even if the stores were willing to bear the additional costs of these units and their respective maintenance, the later two problems mentioned above would still present major barriers. Furthermore, it has been shown that even extraordinary efforts to prompt parents to use seat belts in shopping carts have only a modest influence 3!. An "automatic" child restraint has also been proposed in U.S. Pat. No. 5,651,577 by De Stefano, but even the inventor of this device apparently realizes that the costs associated with this equipment will prohibit stores from voluntarily accepting such a solution since he petitioned the CPSC to require all shopping carts with child seats to have such a device. Finally, it should be noted that in all of the above cases, if the equipment fails to prevent a child from falling out of the seat the risk of an injury is still high, nor has the risk of the cart tipping over been adequately addressed.
The existing situation led a group of pediatricians who studied shopping-cart related injuries 4! to the following strong conclusions: "Injuries related to shopping carts are an important cause of pediatric morbidity, especially among children younger than 5 years. These injuries can also result in death. Shopping carts are not designed for the safe transportation of children. Children transported unrestrained in the shopping cart basket can easily fall from the cart. Restraining belts and infant seats will not adequately prevent injuries from cart tip-overs. Therefore, shopping carts should be redesigned to decrease the risk of injury to children, and transportation of children in shopping carts of the current design should be prohibited."
A redesigned shopping cart that is inherently more stable than the conventional design, and which provides a more-secure child seat, could potentially prevent a large number of serious injuries; especially if such a cart did not require any additional preventative actions by the adult guardian. One obvious means of making the conventional cart more stable would be to widen the width of the wheel base; however, this is not a viable option since the retailers who employ such carts would then have to devout a greater percentage of their floor space to empty aisles. A more attractive option would be a shopping cart which provides a child seat in a lower location than the current design. A lower child-seat location would not only lower the center of gravity of the cart, making it more stable, it would also reduce the distance a child would fall if the cart tipped over or if a child fell out of the child seat, thereby greatly reducing the potential for serious injury if either event does occur. However, the design of a shopping cart with a lower child-seat location is not a trivial matter, since a commercially-available shopping cart must also be "nestable", i.e., it must nest with a cart of a similar design so that the carts may be stored in a compact manner when they are not in use. This is an important requirement that must be met in order for the design to be readily accepted by the retailers which utilize such carts. The simple relocation of the child seat to a lower position within the conventional design is incompatible with this requirement. It is not obvious how to reconcile this nesting requirement with a relocation of the child seat.
Therefore, a new and novel shopping-cart design is required in order to provide a nestable cart with a lower, and inherently safer, child seat. On the other hand, if the new design could also nest with existing designs, then there is the added advantage that retailers could replace their older carts in stages. Additionally, the new design should be about as simple to operate and maintain as the conventional shopping cart.