Vehicular child restraint and child protection system

Abstract

A forward-facing child restraint and a child restraint system providing superior collision protection. The restraint and the system are for use in a vehicle having a lap belt and a shoulder belt. The child restraint system comprises a restraint which may be used with a booster seat, independently of a booster seat or associated with a booster seat.

Claims

1. A child restraint for use in a vehicle having a lap seat belt and a shoulder seat belt, the child restraint comprising: a. a main body part comprising a middle and two side wall segments, said main body part configured to be positioned in front of and on either side of a child; b. said wall segments having exterior outer surfaces which are continuous and generally convex; c. a rigid inner stiffening member spanning the restraint transversely and configured to reliably fix the position of the restraint in relation to the child's body; d. either end of said rigid inner stiffening member configured to be positioned adjacent to the hip bone and pelvic spine on either side of a child; e. a fastener connectable to the lap seat belt comprising a clip on the middle of said middle wall segment of said main body part; f. said fastener so displaced in relation to the child by said rigid inner stiffening member that when the restraint is placed on a child and the lap seat belt is passed through said fastener and the lap seat belt is raised and the vertical inclination of the lap seat belt is increased, whereby when the lap seatbelt is subject to the inertial force of a child's body in a forward collision producing a downward reaction force in the lap seat belt, g. either end of said rigid inner stiffening member is configured to concentrate the reaction force on the hip bone and in front of the pelvic spine on either side of the child, in order to inhibit the rotation of either pelvic spine and the forward movement of the child.

2. A child restraint as claimed in claim 1, wherein either end of said rigid stiffening member of the child restraint is configured to maintain proper pelvic orientation.

3. A child restraint as claimed in claim 1, wherein in addition to said fastener connectable to the lap seat belt comprising a clip on the middle of said middle wall segment of said main body part there is a fastener on either said side wall segment of said main body part each including a retaining clip respectively.

4. A child restraint as claimed in claim 1, comprising: a. an outer shell, made of a suitable resilient molded plastic and, b. an inner structural component, molded in a rigid polymer foam material.

5. A child protection system comprising the combination of a child restraint as claimed in claim 1 and a booster seat, said child protection system being for use in a vehicle having a lap seat belt and a shoulder seat belt.

6. A child protection system as claimed in claim 5, wherein a seat pan of said booster seat is higher at the front than the rear.

7. A child protection system as claimed in claim 5 wherein a seating surface of said booster seat maximizes friction between the child's clothing and the booster seat.

8. A method to protect a child in a vehicle during the dynamics of a frontal impact, said vehicle having a lap seat belt and a shoulder seat belt, the method comprising: a. connecting a child restraint as claimed in any one of claims 1, 2, 3 and 4 to the lap seat belt; b. seating the child on the seat of the vehicle; c. placing the child restraint against the front of the child's pelvis, fastening the lap seat belt with the child restraint and positioning the shoulder belt.

9. A method as claimed in claim 8, wherein the child is seated on a booster seat on the seat of the vehicle.

10. A method as claimed in claim 9, wherein a seat pan of said booster seat is higher at the front than the rear.

11. A method as claimed in claim 9 wherein a seating surface of said booster seat maximizes friction between the child's clothing and the booster seat.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be better understood by way of the following detailed description of embodiments of the invention with reference to the appended drawings, in which:

(2) FIG. 1 is a perspective of the exterior shell of the restraint;

(3) FIG. 2 is a perspective of the interior structural component of the restraint including the transverse stiffening member;

(4) FIG. 3 is a perspective view of the restraint on a child seated on a dedicated booster;

(5) FIG. 4 is a perspective view of the restraint on a child seated on a dedicated booster illustrating the X-, Y- and Z-coordinate axes;

(6) FIGS. 5A and 6A are side views of a child restrained by the seat belt alone (FIG. 5A) and sitting on the booster seat and wearing the restraint (FIG. 6A), illustrating the impact of the invention on seatbelt angle (?XZ) and the corresponding increase in downward pressure on the hips to resist the tendency to submarine;

(7) FIGS. 5B and 6B are sectional views abstracted from corresponding illustrations 5A and 6A illustrating how the invention increases the angle (?XY) between the lap seatbelt and the axis of the seat bight to allow the belt to be more closely aligned with collision forces;

(8) FIG. 7 is a side view of the restraint on a child seated on a dedicated booster seat illustrating diagrammatically how the inertia (I) of the child's torso in a forward impact produces a tension (T) in the lap seatbelt and a downward reaction force (R?) proportional to the angle (?) of the lap seatbelt in relation to the horizontal, resulting in a corresponding reaction force in the booster seat (RN) and a proportional friction force (FRN) opposing the tendency of the child's lower body to slide forward;

(9) FIG. 8 is a median-plane section of the restraint illustrating diagrammatically how the inertia (I) of the child's legs and lower abdomen induces a moment (M) about an axis (O) through the point of contact of the lap seatbelt with the restraint producing an upward reaction force (RM) whose opposition to the downward reaction force (R?) results in a compressive reaction force (C) acting along the axis defined by point O and a point (P), P being the point of contact of either end of the transverse stiffening member with the corresponding surfaces of the upper femurs and pelvic spines;

(10) FIG. 9 is a median-plane section of the restraint illustrating diagrammatically the cam action of the restraint wherein the reaction force RM of FIG. 8 acts upward in opposition to R?, thus augmenting and transforming the otherwise vertically downward expression of R? into the compressive reaction force C acting along the axis O-P.

(11) FIG. 10 is a perspective view of one half of the restraint sectioned in the median plane illustrating the contact between one end of the transverse stiffening member and the pelvic spine and upper femur of the skeleton of a child;

(12) FIG. 11 is a median-plane section of the restraint shown in diagrammatic relation to of the skeleton of a child illustrating the compressive reaction forces between either end of the transverse stiffening member and the corresponding upper femur and pelvic spine;

(13) FIG. 12 is a lateral section of the restraint on its plane of symmetry viewed obliquely and shown in relation to the pelvis of a child;

(14) FIG. 13 is a median-plane section of the restraint;

(15) FIG. 14 is a lateral section of the restraint on its plane of symmetry;

(16) FIG. 15 is a perspective of the booster seat assembly;

(17) FIG. 16 is a median-plane section of the booster seat assembly;

(18) FIG. 17 is a perspective view of the restraint on a child seated on a high-back belt-positioning booster seat;

(19) FIG. 18 is a perspective view of the restraint on a child seated directly on the vehicle seat without use of a booster;

(20) FIG. 19 is a perspective view of a smaller variant of the restraint on a child seated on a dedicated booster.

(21) FIG. 20 is a perspective view depicting the retaining clips on either side wall of the invention.

DRAWINGSREFERENCE NUMERALS

(22) 21 outer shell 22 inner structural component 23 seatbelt retaining clip 24 restraint middle segment 25 restraint end segment 26 stiffening member 27 concave profile of inner structural member 28 contact surface of truncated stiffening member 29 outer shell parallel edges 210 outer shell tapered edges 211 outer shell edge radii 212 slot, seatbelt retaining clip 213 outer shell convex surface 214 concave seatbelt path 215 seatbelt path termination radius 216 perimeter chamfer of structural component 217 front of booster seat pan 218 seat pan of booster 219 booster interior rib 220 raised edge of booster 221 booster seat component 222 booster fabric pad

DETAILED DESCRIPTION OF THE INVENTION

(23) The restraint in its preferred embodiment FIGS. 1, 2 comprises three parts: an outer shell (21) made of a suitable resilient molded plastic over an inner structural component (22) comprising an integral rigid stiffening member (26) and composed of a rigid polymer foam material and a seatbelt retaining clip (23) located on the front of the plastic shell.

(24) When viewed in a transverse section FIG. 14 the exterior of the restraint is convex and symmetrical in relation to the median plane and characterized by three wall segments integrally formed: a wide curved middle segment (24) and side wall segments (25) joined at approximately 45? in relation to the middle segment and approximately half as long as the middle segment is wide.

(25) The exterior shell FIG. 1 is a plastic molding, symmetrical about two perpendicular planes in the form of the afore-mentioned u with a front portion characterized by roughly parallel upper and lower edges (29) and side portions with tapered upper and lower edges (210) terminating and joining in a large radius (211).

(26) There is a seatbelt retaining clip (23) centrally located on the front of the shell with a slot (212) to permit insertion and removal of the lap seatbelt.

(27) The exterior shell may be thermoformed by means of vacuum over an open mold, in which case the seatbelt retaining clip is a separate molded part which may be installed with the body of the clip held captive between the exterior shell and structural component of the restraint, with the two prongs of the clip protruding through an opening central to the front of the exterior shell.

(28) In an alternative embodiment, the exterior shell is formed under pressure in a closed mold in which case the seatbelt retaining clip may be an integral part of the shell.

(29) The front and side top and bottom exterior surface areas (213) of the exterior shell are slightly convex for additional stiffness and are formed integrally with the middle surface areas (214) on either side of the seatbelt clip which are slightly concave, forming a shallow impression crossing the front of the shell and terminating in a radius (215) on either side, suggesting the path of the seatbelt. These impressions contribute to the initial rigidity of the restraint and provide a predictable failure mode in a collision when the restraint is subject to the extreme pressures exerted by the seatbelt.

(30) The inner structural component comprises an integral rigid stiffening member (26) spanning the restraint in a transverse direction and configured to reliably fix the position of the restraint in relation to the child's body, either end, P, FIGS. 8, 9, 10, 12 of the rigid stiffening member being adjacent to the hip bone and pelvic spine on either side of the child.

(31) The stiffening member (26) is symmetrical in relation to both the median and the transverse planes of symmetry with the profile of a truncated triangle when viewed in a median-plane section FIG. 13.

(32) The exterior profile of the stiffening member in transverse plane section FIG. 14(27) is concave and sweeps around the abdomen of the child with the truncated face FIG. 2(28) of either end poised to make positive contact with and facilitate the transfer of reaction forces FIGS. 8, 9, 10, 11 to the hips and pelvis.

(33) Referring to FIGS. 15, 16, the seat pan of the booster is low and wedge-shaped in profile, the seating surface (218) being higher at the front than the rear. The surface is roughly flat in the centre and concave towards the sides and rear for a more uniform distribution of the pressure on the child's buttocks and curved downwards along the front (217) to avoid areas of concentrated pressure on the child's thighs.

(34) Either side (220) of the molded seat is raised in the mode of a seat bolster in a sports/racing car for the comfort and support of the child and to convey the high performance character of the product.

(35) The booster comprises a molded polymer seat component (221). The interior of the molded seat may have a lattice of ribs to maintain the integrity of the seat when subjected to the downward reaction force of a collision.

(36) In one embodiment of the invention the underside of the seat component is covered by a flat panel so the exterior walls and interior ribs do not mar the upholstery of the vehicle. The panel may be located on the seat component by means of positive male features integral to the panel and corresponding negative female features in the interior lattice structure of the seat component. The panel may incorporate Isofix/LATCH connectors to affix the seat securely to the frame of the vehicle.

(37) In an alternative embodiment of the invention there are features on either side of the booster to prevent its forward translation in a collision by means of the lap seatbelt, these features also serving as arm rests.

(38) The seating surface may be covered by a textured fabric pad (222), securely fastened. The fabric shall be heavyweight woven pile polyester, chosen to maximize friction between the child's clothing and the seat.

(39) Operation

(40) The invention restrains the child by creating the optimal conditions for the translation of the horizontal inertia of the her body acting on the lap seatbelt into downward reaction forces in the restraint to hold her tight between the restraint and the low booster.

(41) The restraint serves as a protective exoskeleton, bridging the vulnerable abdomen in a lateral direction and targeting reaction forces on the pelvic spines and the hips with either end of its wedge-shaped interior profile.

(42) The restraint and the booster together compensate for variations in lap seatbelt geometry by simulating the lower torso of an adult passenger to achieve a snug lap seatbelt adjustment and raise and advance the point of action of the lap seatbelt relative to the child.

(43) In cases where lap seatbelt anchor points are either too high or too far forward for a child, the invention improves lap seatbelt fit and performancewithout moving the child away from the seatback and only minimally elevating herby advancing and raising the point of contact between the belt and the child FIGS. 5A, 6A.

(44) This avoids the disadvantage of the belt-positioning booster of significantly raising and advancing the child, thereby increasing free movement and the risk of impact with a forward surface in a collision.

(45) In raising the point of contact between the seatbelt and the child in relation to the seatbelt anchor locations FIGS. 5A, 6A, the restraint, in conjunction with the tapered booster increases the belt angle (?XZ) to increase downward pressure on the hips and reduce the risk of the child sliding forward under the belt in a collision.

(46) The booster provides the stage for the translation of the elevated downward reaction force into the increased friction force (FRN)FIG. 7 opposing forward collision forces, isolating the pelvis from the inertia of the legs.

(47) The booster FIG. 15 also enables the child to bend her legs at the knee in order to assume the optimal seated position, low and against the back of the rear seat of the vehicle, critical to the collision performance of the invention.

(48) A snug seatbelt adjustment is necessary to minimize free movement in a collision and take maximum advantage of this optimal seated position. The restraint improves lap seat adjustment by adding its thickness to the cross-sectional area of the child the belt wraps around FIGS. 5B, 6B.

(49) It thus increases the angle (?XY) in the X-Y plane between the lap seat belts and the axis of the seat bight on either side to bring the belts into a better alignment with collision forces, thereby allowing them to be adjusted more snugly and increasing their efficiency.

(50) The invention thus supports the role of the pelvis in restraining the child by promoting proper pelvic orientation at the onset of a collision and by isolating the pelvis from the collision forces promoting its counter-clockwise rotation.

(51) The restraint translates horizontal collision forces into a compressive reaction force focused on the pelvic spines and the hips to arrest the forward movement and counter-clockwise rotation of the pelvis. It does this by means of a reaction force due to an internal moment in the device.

(52) In a forward collision FIG. 8 the restraint creates an opposition between (i) the downward reaction force (R?) due to the forward inertia of the upper body acting upon the lap seatbelt with a diagonal inclination ?, and (ii) an upward reaction force (RM) resulting from a counter-clockwise moment (M) about an axis through the most forward point of contact of the belt with the restraint (O) due to the inertia (I) of the legs.

(53) The opposing reaction forces are expressed as a combined compressive reaction force (C) concentrated on the pelvic spines and the hips, which may be understood as a follows: Raising the point of contact of the seatbelt with the restraint at point O relative to the point of contact (P) of the restraint with the child's hips and pelvis results in the counter-clockwise moment M about point O due to the inertial force I of the legs; Merely raising the point of contact of the seatbelt with the restraint without also advancing point O relative to point P does not produce the upward reaction force RM however; By advancing point O in relation to point P, in order for moment M to produce a counter-clockwise rotation of the restraint it must displace point O upward by a distance FIG. 9(?z) producing a vertical reaction force FIG. 8RM acting upward in opposition to R?, thus augmenting and transforming the otherwise vertically downward expression of R? into the compressive reaction force C acting along the axis O-P.

(54) The restraint thus functions FIG. 9 as a cam rotating about an axis through its point of contact with the lap seatbelt O, with either end P of the transverse stiffening member the lobes of the cam, distributing the compressive reaction force between O and P over the forward edge of the pelvic spine and the top of the upper thigh over the hip joint on either side of the child FIGS. 9, 10.

(55) The stiffening member thus serves both structural and mechanical purposes.

(56) Structurally, it: preserves the geometry of the restraint in the X-Z plane by preventing its collapse in a collision; acts as a bulkhead in the Y-Z plane, spanning and protecting the child's vulnerable abdomen from horizontal collision forces;

(57) Mechanically, it: serves at either end at P to augment and concentrate reaction forces on the front of either pelvic spine and the hips through a cam action about an axis through the point of contact O of the lap seatbelt with the restraint FIGS. 8, 9, 10.

(58) The booster provides the stage FIG. 7 on which the downward reaction force R? in the restraint translates into the frictional force FRN opposing the forward movement of the child and relieving pressure on the pelvis due to the inertia of the child's legs.

(59) The seat pan FIG. 16(218) of the booster is taller at the front than the rear to allow the child to bend her legs at the knee. The rear of the seat pan of the booster is substantially lower than a conventional belt-positioning booster and its gentle rearward slope encourages her to sit comfortably with her back against the seatback of the car without slouching.

(60) This lower seating position is possible because it is the seatbelt positioning aspect of the restraint in lieu of a high booster which increases lap seatbelt angle by raising the point of contact of the seatbelt with the child in relation to the seatbelt anchor locations.

(61) The upright seating position promoted by the booster of the invention promotes optimal pelvic orientation and seatbelt adjustment to minimize the free movement of the child's body in the event of a forward collision, reducing the rotation of the lap seatbelt about its anchors to preserve belt angle and coupling the child more securely to the vehicle to exploit its capacity to absorb the energy of the collision forces.

(62) Use of the invention does not diminish the crucial role of the shoulder seatbelt, nor does it preclude use of a device to provide an optimal shoulder belt fit for a smaller child if necessary.

(63) Should the shoulder belt nonetheless not serve its purpose, as may occur when the child jack-knifes in an off-centre collision, the restraint will reduce the severity of belt-inflicted abdominal injuries.

(64) Advantages

(65) In a collision the invention extends a greater margin of protection to a child passenger relative to a traditional belt-positioning booster in several distinct ways: 1. by placing the belt-positioning feature ahead of the child it is able to optimize the child's seating position, low and against the back of the rear seat of the vehicle, as far from the vehicle's front seat as possible, thus putting her at the least possible risk of impact with that surface in the event of a collision; 2. in situating the child low and against the back of the rear seat of the vehicle it reduces her unrestrained forward translation in the event of a collision to more fully exploit the vehicle's capacity to absorb the energy of the collision forces; 3. as a belt-positioner the invention promotes a snug seatbelt adjustment and brings the belts into a better alignment with collision forces by increasing the angles (?XY) between the seatbelts and the seat bight, to preserve her optimal seated position to the full extent possible; 4. by optimizing the child's seating position and facilitating a snug seatbelt adjustment the invention promotes proper pelvic orientation at the outset and during a collision; 5. as a belt-positioner and load-transfer device, it increases the angle (?XZ) of the lap seatbelt in relation to the horizontal collision forces to increase the downward force on the upper thighs, increasing the friction between the child and the booster to isolate the pelvis from the inertia of the legs; 6. by situating the child low and against the back of the rear seat of the vehicle and reducing the child's forward translation in a collision, the rotation of the lap seat belt about their anchors is reduced and the angle (?XZ) of the lap seatbelt in relation to the collision forces is better preserved; 7. as a load-transfer device, it translates forward collision forces into a compressive reaction force in its transverse stiffening member through the opposition of a downward reaction force due to the forward inertia of the upper body acting upon the lap seat belt, and an upward reaction force resulting from a counter-clockwise moment due to the inertia of the legs, targeting the combined compressive reaction forces on the pelvis and the hips to stabilize and arrest both the forward translation and the counter-clockwise rotation of the pelvis.

Alternative Uses and Embodiments of the Restraint

(66) The restraint may either comprise an outer shell and an inner structural component or be rotationally-molded with the respective exterior surfaces areas of the exterior outer shell and the inner structural component integrally formed to create a hollow plastic shell. The shell may be filled with foam for additional rigidity.

(67) The restraint may be used either with a dedicated booster or in combination with a suitable third-party booster seat of either the backless or high-back variety FIG. 17.

(68) Where the restraint is used in relation to a booster seat it may be combined with the booster seat by fastening means other than the lap seatbelt with the lap seatbelt passing in front of the restraint but not attached to the restraint.

(69) The restraint may also be used independently of a booster by an older child who is tall enough she is able to bend her legs at the knee to sit comfortably on the vehicle seat with her back against the back of the seat without slouching FIG. 18.

(70) Although intended primarily for children who have graduated from child car seats but are not sufficiently mature to use a lap seatbelt without serious risk of injury, application of the restraint need not be limited to children up to the age of ten years and may be extended to adolescents and adults including pregnant women.

(71) Application of the restraint need not be limited to use in passenger vehicles and its compact size, portability and light weight make it suitable for use anywhere children would otherwise be protected only by a lap seatbelt such as on aircraft.

(72) Where the requirement for protection from the lap seatbelt may not be as acute, such as in the case of an older child, a reduced variant of the restraint FIG. 19 may serve a more limited purpose: by reducing its extent and coverage of the body, as viewed in a median plane section, although the belt-positioning function of the device may be compromised including the ability of the device to concentrate collision forces on the hips and pelvis by means of an internal moment, some functionality is retained including a limited capacity of the device to span and protect the abdomen of the passenger to direct collision forces to the hips and pelvic spines.