CHILD SAFETY SEAT

Abstract: The safety seat has a harness having shoulder straps (14, 15; 114, 115) which are adjustable by means of a conveniently-located remote adjustment device. In the embodiment of Figs. 1 to 4 the shoulder straps pass through slots (18, 19) in the seat backrest and are connected to a cord (32) and a further strap (22) which passes through a snubbing device (24) having an operating knob (52). To adjust the harness, the knob (52) is pulled to release the strap (22) and the free end of the strap (22) or cord (32) pulled to move it an appropriate amount. The knob (52) is then released. In Figs. 5 to 7 the shoulder straps are connected to a rod (128) onto which they are wound by rotation of a handle (142). Axial movement of the handle (142) frees the rod (128) for unwinding of the straps.

Description: CHILD SAFETY SEAT DESCRIPTION This invention relates to child safety seats of the kind which are used in vehicles, for example motor vehicles. Such child safety seats are usually provided with a harness for securing a baby or child in.the seat, the seat also being provided with anchoring -means whereby the seat can be anchored to the structure of a vehicle, for example to standard safety belt anchorages when the seat is mounted on a standard passenger seat in a motor vehicle. The harnesses of known child safety seats usually comprise left and right shoulder straps which pass over the baby or child's shoulders and are secured by a releasable buckle to each other and to respective lap straps in the region of the baby or child's waist. For adjustment of the size of such a harness to accommo¬ date babies and children of different sizes, each houlder strap is usually provided with its own adjustment device. Adjustment of these devices is often a troublesome and time-consuming process, particularly because they are close to the child or baby's body. Moreover, the devices can cause damage or injury to the child, especially, as is often the case, when the devices are also positioned adjacent the child's face. Such damage or injury is particularly likely in the event of a vehicle in which the seat is mounted being involved in an accident. The present invention provides a child safety seat comprising a seat member, the seat member having squab and backrest portions and the seat including a safety harness for an occupant of the seat and means for adjustment of the size of the safety harness, the adjustment means being operable from a position remote from the harness. The seat member conveniently comprises a one-piece shell of moulded plastics material. Advantageously, the adjustment means are operable manually from at least one position adjacent an edge of the seat member. This edge may conveniently be the forward edge of the squab portion and/or the upper edge of the backrest portion. However, in other embodiments, the adjustment means are operable manually from a positio at the side of the seat member. Conveniently, the harness comprises left and right shoulder straps which pass through respective apertures in the backrest portion of the seat member and are operatively connected behind the seat member to the adjustment means which is operable to adjust the size of the harness by adjustment of the effective length of the shoulder straps. The adjustment means may comprise a manually- rotatable element to which the shoulder straps, or a further strap or other flexible elongate element to which the should straps are connected behind the seat member, are anchored and around which the strap(s) or other elongate element are wound when the rotatable element is rotated, the adjustment means also including locking means operable to prevent rotation of the rotatable element in response to a pull on the harness. Conveniently, the rotatable element comprises a shaft which extends transversely of the seat member between mountings in which it is journalled, the shaft preferably having means for its manual rotation operatively connected to an end portion of the shaft extending beyond one of the mountings. The rotatable shaft is conveniently positioned at the rear of the seat member, adjacent the join of the squab and backrest portions. When the shaft is so positioned, the mountings may be shaped to provide surfaces which are positioned for contact with a generally-horizontal surface in order to support the seat in an upright position on the generally-horizontal surface. When the seat member comprises a one-piece shell of moulded plastics material, the mountings may be formed as part of the moulding. The locking means for the rotatable element may comprise first and second annular sets of teeth which extend around the axis of rotation of the rotatable element and are respectively rotatable with the rotatable element and fixed against rotation relative thereto, the sets being relatively movable in the axial direction between a first position in which the teeth engage to lock the rotatable element against rotation in response to a pull on the harness and a second position in which manual rotation of the element possible. Resilient biassing means may be provided to urge the sets of teeth into their first position. Conveniently, the teeth of at least one set of teeth are ramped so that rotation of the first set in the winding-in direction produces axial movement from the first to the second positions of the teeth sets. When the rotatable element comprises the shaft mentioned above, the second set of teeth is conveniently positioned on one of the said supports. In one preferred construction, the first set of teeth is formed on an operating handle slidable on the shaft extension portion and the second set of teeth is formed on an adjacent support surface, the operating handle being keyed to the extension portion so that rotation of the handle causes rotation of the shaft. With such an arrangement, the operating handle is readily positioned adjacent one side of the seat. The adjustment means may otherwise comprise an elongate element, conveniently a flexible element such as a further strap, to which the shoulder straps are joined and which is securable at a point spaced from the join with the shoulder strap to the safety seat, and a device for adjustment of the effective length of the elongate element. Preferably, the length adjustment device has a first part which is immovable relative to the safety seat and a second part which is movable relative to the first part between a clamping position in which the elongate element is secured to the safety seat by being clamped between the two parts and a free position in which the elongate element can be moved through the device for adjustment of its effective length. Conveniently, the length adjustment device includes resilient biassing means biassing the first and second parts into their clamping position. To facilitate such movement of the elongate element, a free end of the elongate element may extend to an edge of the seat structure where it can be pulled manually to move it through the length adjustment device when the second part of this is in its free position. For movement of the elongate element in the reverse direction, a second elongate element, preferably a flexible element such as another strap or a cord, is preferably attached to the first elongate element and also extends to an edge of the seat structure for manual operation. The length adjustment device may also be operable from adjacent an edge of the seat member, for example by having an operating member adjacent the front edge of the squab portion of the seat member. In some embodiments of the invention, the operating member of the length adjustment device and the free end of the elongate element are positioned adjacent each other at the forward edge of the squab portion of the seat member, whilst the second elongate member extends to the upper end of the backrest portion of the seat member. When the first elongate element is formed by a strap, the second part of the length adjustment device conven¬ iently comprises a rod or bar around which the strap is looped and which in the clamping position lies adjacent a surface extending parallel to the rod or bar, the strap being trapped between the rod or bar and the said surface in the clamping position. When the seat member is of a one-piece moulded con¬ struction, a housing for the length adjustment device is conveniently moulded integrally with the squab portion of the seat member. Alternatively, the length adjustment device may be formed as a separate unit which is attached to the seat member. Embodiments of the invention will now be described by way of example with reference to the drawings, in which: Figure 1 is a perspective view showing the front of a child safety seat. Figure 2 is a perspective view showing the rear of the seat of Figure 1 , Figure 3 shows a strap length adjustment device of a slightly modified version of the seat of Figure 1 , Figure 4 is a longitudinal section through a forward part of the squab portion of the seat member, showing the strap length adjustment device shown in Figure 3, Figure 5 is a perspective view showing the rear of another child safety seat. Figure 6 shows a harness-size adjustment device of the seat of Figure 5 partly in section, and Figure 7 is a perspective view of some of the parts of the adjustment device of Figure 6. Figure 1 shows a seat member of a child safety seat, the seat member being a one-piece moulding of plastics material and comprising a squab portion 10 and a backrest portion 12. The seat member has mounting means (not shown) for mounting the seat on a passenger seat of a motor vehicle. The safety seat is fitted with a safety harness which comprises left and right shoulder straps 14, 15 and left and right lap straps 16, 17, all of which are fitted with buckle members which can be connected together to secure a child or baby occupant of the seat by means of the harness. The shoulder straps 14, 15 pass through respective slots 18, 19 in the backrest portion 12 of the seat member. At the rear of the backrest portion 12, the shoulder straps 14, 15 are connected together at a fitment 20 (see Figure 2) which is also connected to a further strap 22 which passes centrally of the backrest 12 and squab 10 portions to a length adjustment device 24 and, after passing through the length adjustment device 24 and through a slot 26 in the forward edge of the squab portion 10 of the seat, extends to a free end where it is fitted with a member 30 which is shaped for convenient gripping by hand. The fitment 20 is also attached to a cord 32 which passes upwardly behind the backrest portion 12 through a circular hole 34 in the upper edge of the backrest portion 12 to a ring 36 which can also be conveniently gripped by hand. The fitment 20, strap 22, device 24, cord 32, member 30 and ring 36 constitute parts-of the means for adjustment of the size of the harness of the seat. A slightly modified version of the length adjustment device 24 is shown in more detail in Figures 3 and 4. It comprises a housing 38 which is moulded integrally with the squab and backrest portions 10, 12 of. the seat member. A rear wall 40 of the housing has a slot 42 through which a loop of the further strap 22 is passed. The loop also passes downwardly through an opening 44 in a metal plate 46 which is secured by four screws 47 to the housing 30. After passing through the slot 42 and the opening 44, the loop in the further strap 22 passes around a rectilinear bar portion 48 of an operating member 50 of the length adjustment device 24. End portions of the rectilinear bar portion 48 are in sliding contact with the plate 46, an exaggerated clearance being shown in Figure 4. The operating member 50 has a stem 51 which extends through a circular hole in the front edge of the squab portion 10 to a control knob 52 which is thus positioned adjacent the free end of the further strap 22. The shape of the stem 51, and hence the position of the knob 52, is somewhat different in the seats of Figures 1 and 2 and Figures 3 and 4 but the adjustment devices 24 of the seats operate identically. A helical compression spring 54 surrounds the stem 51 and acts between the inner surface of the front edge of the seat squab portion 10 and an abutment 56 on the stem 51 to bias the operating member 50 into a clamping position in which the further strap 22 is trapped or snubbed between the bar portion 48 of the operating member 50 and the rearward edge of the opening 44 in the plate 46. Pulling on the knob 52 moves the operating member 50 against the bias of the spring 54 into a free position in which the belt 22 can be pulled in either direction through the device 24. It has. been found that the path followed by the strap 22 through the adjustment device 24 allows adjustment of the effective length of the strap 22 to be particularly easily adjusted, the strap 22 being movable smoothly through the device in either direction with little effort. For use, the child's safety seat is first mounted by means of its mounting means on a passenger seat in a motor vehicle. The size of the harness can be adjusted by altering the effective length of the shoulder straps 14, 15. This alteration is acheived by increasing or decreasing the effective length of the strap 22 between the fitment 20 and the adjustment device 24. This effective length can be increased by pulling on the ring 36 attached to the cord 32 after releasing the length adjustment device 34. Release is attained by pulling the knob 52 on the stem 51 of the operating member 50 to cause the bar portion 48 of the operating member 50 to move to its free position in which it is spaced from the edges of the opening 44. In this position the strap 22 can be pulled upwardly through the device 24. To decrease the length of the shoulder straps 14, 15, the knob 52 is again pulled out and the member 30 on the free end of the further strap 22 is gripped manually to pull the strap 22 through the slot 26 until the shoulder straps 14, 15 are of the required length. The control knob 50 is released and the strap 22 is clamped firmly in position to hold the shoulder straps 14, 15 at their adjusted lengths. The child safety seat shown in Figures 5 to 7 also has a seat member which comprises a one-piece plastics moulding providing a squab portion 110 and a backrest portion 112. The seat member has mounting means (not shown) for attachment to a vehicle and a safety harness which includes left and right shoulder straps 114, 115 which pass through slots 118, 119 in the backrest portion 112 and extend to a harness-size adjustment device 124. The device 124 includes left and right hollow support trunnions 125, 126 (see Figure 6) which are moulded integrally with the seat member and have lower surfaces 127 which provide a base to support the seat member in an upright position on a generally- horizontal surface. A winding shaft 128 passes through aligned apertures 129 in outer and inner side walls 130, 131 of the left trunnion 125 and extends through an aperture 132 in the inner side wall 133 of the right trunnion 126. A washer 134 and split pin . 135 within the trunnion 126 secure the end of the shaft 128 against withdrawal. The winding shaft 128 is hollow and has an axial slot 136 (see Figures 6 and 7) extending from the end secured in the right trunnion 126 to a point adjacent the inner side wall of the left trunnion 125. The slot 136 receives the shoulder straps 114, 115 and the straps are anchored to the shaft by folded over and stitched down end portions 137 (only one shown in Figure 7) which are slid into the hollow interior of the shaft before fitting of the shaft to the seat member. After fitting of the shaft, the end portions are captive in the hollow interior and occupy side-by- side portions of the shaft. An extension portion 140 of the shaft 128 extends beyond the left trunnion 125 and, as can be seen in Figure 7, is squared so that an operating knob 142 having a complementary square aperture is slidable on the extension portion 140 but keyed thereto so that turning of the knob 142 causes the shaft 128 to rotate. The knob 142 is hollow and contains a helical compression spring 143 which acts between the knob 142 and a pair of outturned lugs 144 at the outer end of the extension portion 140 to urge the knob 142 towards the left trunnion 125. A cover 145 closes the hollow interior of the knob 142 which is knurled around its outer periphery for gripping by hand. The outer side wall 130 of the left trunnion 125 is formed with a set 146 of ramped ratchet teeth and a complementary set 148 is formed on the adjacent end face of the knob 142. The spring 143 urges the teeth sets 146, 148 into engagement with each other. The teeth of the sets 146, 148 are shaped to prevent rotation of the winding shaft 128 in a first direction in response to a pull on the shoulder straps 114, 115. However, rotation of the knob 142 in a second, opposite direction causes the ramped surfaces of the teeth to co-operate to produce an axial shift of the knob 142 against the bias of the spring 143 and the shaft can then be rotated to wind the straps 114, 115 onto the shaft. Accordingly, to reduce the size of the harness of the seat of Figures 5 to 7, the knob 142 is rotated manually in the second direction and the shoulder straps 114, 115 are wound onto the " winding shaft 28 and their effective lengths reduced. To facilitate this adjustment of the harness, the knob 142 can of course be pulled manually against the bias of the spring 143 in order to bring the teeth sets 146, 148 completely out of contact with each other. When the harness has been reduced to the desired size, the knob 142 is released and the teeth sets 146, 148 and spring 143 lock the winding shaft against rotation in the first direction. To increase the size of the harness this locking is released by outward manual movement of the knob 142 which frees the winding shaft 128 for rotation in the first direction in response to a manual pull on either shoulder strap. Release of the knob at the desired harness size causes re-locking of the shaft against unwinding movement. In a modified version of the seat of Figures 5 to 7, the shoulder straps 114, 115 are connected together behind the backrest portion 112 to a fitment similar to the fitment 20 of the seat, of Figures 1 to 4, the fitment also being secured to a further strap which extends to a winding shaft similar to the shaft 128 but of a length appropriate to a single strap being stored on it. It will be seen that both child safety seats described avoid altogether the need to have length adjustment devices in harness straps which are in contact with or adjacent the baby or child's body and face. The size of the harness can be quickly and easily adjusted in one seat by manipulation of the control knob 52 with one hand and the member 30 or ring 36 with the other and in the other seat simply by rotation of the control knob 145 or by manipulation of the control knob 145 and the harness straps 114, 115. In both seats the length of the two shoulder straps is automatically adjusted simultaneously, without there being any need to set two adjustment devices to compatible settings, as in the case with known safety seats in which each shoulder strap of the harness has its own adjustment device.

Claims: CLAIMS 1. A child's safety seat for use in a vehicle, the seat having a harness comprising elements for restraining an occupant of the seat and means for adjustment of the size of the harness, the adjustment means being operable from a. osition remote from the harness. 2. A child's safety seat for use in a vehicle, the seat having harness elements for restraining an occupant of the seat and adjustment means for at least one harness element, the harness elements protruding forwardly into a zone of the seat occupied by an occupant and the adjustment means being operable at a location remote from the protruding elements. 3. A seat according to claim 1 or 2, in which the adjustment means are operable manually from a position adjacent an edge of the seat. 4. A seat according to claim 3, in which the adjustment means are operable manually at at least one of the forward edge of a squab portion of the seat and the upper edge of a backrest portion of the seat. 5. A seat according to claim 3, in which the adjustment means are operable manually at a side of the seat. 6. A seat according to any preceding claim, in which the harness elements comprise left and right shoulder straps which protrude forwardly from respective apertures in a backrest portion of the seat and are operatively connected behind the seat to the adjustment means which -is operable to adjust the size of the harness by adjustment of the protruding length of the shoulder straps. 7. A seat according to claim 6, in which the adjustment means comprises a manually-rotatable element positioned behind the seat, the shoulder straps being connected to the rotatable element to be wound therearound and the adjustment means including locking means operable to prevent rotation of the rotatable element in response to a pull on the harness elements. 8. ' A seat according to claim 7, in which the shoulder straps are connected to the rotatable element by respective extension strap portions extending from the backrest apertures to the rotatable element. 9; A seat according to claim 7 or 8, in which the rotatable element comprises a shaft which extends transversely of the seat between mountings in which it is journalled. 10. A seat according to claim 9, in which the shaft has means for its manual rotation operatively connected to an end portion of the shaft extending beyond one of the mountings. 11. A seat according to claim 9 , in which the mountings are shaped to provide surfaces located for contact with a generally-horizontal surface in order to support the seat in an upright position on the generally-horizontal surface. 12. A seat according to any one of claims 7 to 11, in which the rotatable element is positioned adjacent the joint of squab and backrest portions of the seat. 13. A seat according to any one of claims 7 to 12, in which the locking means comprise first and second annular sets of teeth which extend around the axis of rotation of the rotatable element and are respectively rotatable with the rotatable element and fixed against rotation relative thereto, the sets being relatively movable in the axial direction between a first position in which the teeth engage to lock the rotatable element against rotation in response to a pull on the harness elements and a second position in which manual rotation of the element is possible. 14. A seat according to claim 13, including resilient biassing means- urging the sets of teeth into their first position. 15. A seat according to claim 12 or 13, in which the teeth of at least one set of teeth are ramped so that rotation of the first set in the winding-in direction produces axial movement from the first to the second positions of the teeth sets. 16. A seat according to any one of claims 13 to 15, in which one set of teeth is formed on an operating handle slidable on the rotatable element and the second set of teeth is formed on an adjacent part of the seat, the operating handle being keyed to the rotatable element so the rotation of the handle causes rotation of the rotatable element. 17. A seat according to claim 6, in which extension strap portions of the shoulder straps extend from the backrest apertures of the seat and the adjustment means comprises an elongate element, to which the extension strap portions are joined and which is securable to the seat at a point spaced from the join with the extension strap portions, and a device for adjustment of the effective length of the elongate element. 18. A seat according to claim 17, in which the length adjustment device has a first part which is immovable relative to the seat and a second part which is movable relative to the first part between a clamping position- in which the elongate element is secured to the seat by being clamped between the two parts and a free position in which the elongate element can be moved through the device for adjustment of its effective length. 19. A seat according to claim 18, in which the length adjustment device includes resilient biassing means biassing the first and second parts into their clamping position. 20. A seat according to claim 18 or 19, in which a free end of the elongate element extends to an edge of the seat where it can be pulled manually to move it through the length adjustment device when the second part thereof is in its free position. 21. A seat according to claim 20, in which, for movement of the elongate element in the reverse direction, a second elongate element is attached to the first elongate element ana also extends to an edge of the seat where it can be operated manually. 22. A seat according to any one of claims 17 to 21, in which the length adjustment device is operable from adjacent an edge of the seat.' 23. A seat according to any one of claims 17 to 22, in which the elongate element comprises a strap and the second part of the length adjustment device comprises a rod or bar around which the strap is looped and which in the clamping position lies adjacent a surface extending parallel to the rod or bar, the strap being trapped between the rod or bar and the said surface in the clamping position. 24. A seat according to any preceding claim, comprising a one-piece shell of moulded plastics material, the shell providing squab and backrest surfaces for support of the occupant of the seat. 25. A child's safety seat substantially as herein¬ before described with reference to Figures 1 to 4 or Figures 5 to 7 of the drawings. 26. Any novel feature or combination of features HdiiasccllnoesoeHd Hh_earT-.e_-iinn

Inventors: ANDERSON ALEXANDER BARRIE, ANDERSON, ALEXANDER, BARRIE
Applicants: ASE UK LTD, ASE (UK) LIMITED
Application year: 1985
Main classification: B60N1
IPC codes: B60N2