MULTI-ROLE PUSHCHAIR

Abstract: A pushchair which can be used as a child's seat on a bicycle or as a safety seat in a car. The pushchair comprises a foldable wheeled frame to which is attached a moulded seat shell (10). The frame folding mechanism includes means (37) for releasably securing and locking the pushchair to a purpose-designed carrier rack (46, 47), (48, 49, 50) attached to the bicycle. In a preferred embodiment, the geometry of the frame folding mechanism is such that it imparts a sprung detent action, whereby the frame is held securely to the carrier rack. An additional safety latch (45) provides duplicated security of attachment. In the car seat role (figure 7), the folded pushchair is secured to the car body structure by means of the three-point lap-and-diagonal seat belt (70) provided for the use of back-seat passengers. An additional tether strap 68 may retain the upper part of the pushchair.

Description: MULTI-ROLE PUSHCHAIR This invention relates to a pushchair for a child, and one object is to provide a design of pushchair which is easily adapted for other uses than merely carrying a child along a pathway. Seats for carrying a child on a bicycle are of course known, and some of them are constituted by a moulded impact-resistant shell with a harness to retain the child in the shell. Typically the shell is attached to a carrier frame which is in turn attached to the frame of a bicycle. Similarly, child's safety seats in cars are known, and some of them are constituted by a moulded impact-resistant shell with a high back and sides, together with a harness which is used to retain the child in the shell. There may then be a separate harness co-operating with fastenings secured to the bodywork of the car which is used to retain the shell in position within the car. From one point of view, the present invention can be considered to be a means of enjoying the advantages of such a child's bicycle seat, with means for using the same moulded shell in other applications, and in particular as a part of a pushchair, which in turn can provide the functions of a child's safety seat in a car. In order to occupy the minimum of space, the pushchair frame will in general be in a folded state when it is used as a child's seat on a bicycle, or as a child's safety seat in a car. From another point of view, the present invention combines, in a single piece of equipment, the advantages and functions of a pushchair, a child's bicycle seat, and a child's car safety seat. Transition from one role to another can be accomplished in a matter of seconds, without the use of any tools, and the child may remain safely harnessed in the seat at all times. Provision of means for carrying items of shopping or other goods in addition to the child enables the pushchair to be used to advantage in places where cars and bicycles are not permitted, such as shopping malls or pedestrianised precincts. Then, on return to the car or bicycle, items of shopping can be easily transferred to whichever vehicle is being used. This facility is of particular value to users of bicycles, who would otherwise have no means of carrying either the child or the shopping when walking in pedestrianised areas. According to the present invention there is provided a pushchair comprising a moulded seat shell mounted on a frame, said frame being moveable between a first folded configuration and a second extended configuration, the frame having means for releasably securing it to a carrier rack on a bicycle. The frame may comprise a number of transverse members for supporting the seat shell, a pushing-handle assembly having a pair of pushing-handle rods, a lower rear part, a pair of front side members connected by a first transverse member, and a pair of rear side members. The frame may comprise a number of transverse members for at least partially supporting the seat shell, and no additional transverse members lower than those which at least partially support the seat shell, thereby enabling the pushchair to straddle the rear wheel of a bicycle in both folded and extended configurations . The pushchair may be provided with an additional safety latch attached pivotally to the carrier rack on the bicycle, so that when the frame is in its fully-folded configuration the safety latch engages with a further transverse member, said further transverse member being attached between the pushing-handle members of the foldable frame. The pushchair may also be provided with means for releasably securing the frame, in its folded configuration, to the inside of a car. There may be provided on the pushchair a removable tray for the carriage of goods. The removable tray may be carried on an separate rack mounted on the handlebars of the bicycle. The invention may be carried into practice in various ways, and by way of example an embodiment will be described with reference to the accompanying drawings in which :- Figure 1 shows in perspective, the pushchair in its expanded condition, and with a goods tray attached; Figure 2 shows in perspective, the pushchair in its expanded condition, but with the moulded seat shell and near side-plate removed, such that the the seat mounting chassis frame is visible; Figure 3 shows in perspective, a view of the folded pushchair from the front quarter; Figure 4 shows in perspective, a view of the folded pushchair from the rear quarter; Figure 5 shows in perspective, the carrier rack attached to the frame of a bicycle; Figure 6 shows in perspective, the pushchair in its folded condition mounted on the carrier rack of Fig 5; Figure 7 shows in side elevation, the pushchair in its folded condition installed inside a car; Figure 8 shows in side elevation, the frame folding mechanism geometry. Full lines denote the frame in its expanded condition and chain-dotted lines denote the folded condition. Figure 9 shows in side elevation, a longitudinal sectional view of the seat-mounting chassis frame, with, attached to it, a moulded side plate and the pivoted portion of the trapeze-like assembly, when the pushchair frame is in the expanded condition; Figure 10 shows in side elevation, a longitudinal sectional view of the seat-mounting chassis frame of Fig 9 mounted on the carrier rack of Fig 5. The pushchair frame is in the folded condition, such that it is engaged with, and locked onto, the carrier rack. Also shown is a secondary latch which ensures that the pushchair frame remains in the folded condition and fully locked onto the carrier rack; Figure 11 shows in third-angle projection, a moulded side-plate. This item is "handed", that drawn being the left-hand part; Figure 12 shows a frontal view of the trapeze-like assembly which forms part of the frame folding mechanism and which incorporates hooks for engaging with the bicycle carrier rack; Figure 13 shows in third-angle projection, the seat-mounting chassis frame. The seat moulding is attached by means of bolts passing through holes marked "H"; Figure 14 shows a rear view of the pushchair frame transverse structure, which is located behind the upper portion of the seat moulding; Figure 15 shows a cross-sectional view through the axis of symmetry of Fig 14, with details of the headrest, shoulder-strap attachment, and tether-strap attachment; Figure 16 shows in third-angle projection, detail of the pushchair frame locking latch mechanism, with the frame locked in its expanded condition. Chain-dotted lines show the frame in a part-folded state; Figure 17 shows in plan and side elevation, details of a moulded goods tray and its attachments to the pushchair structure; Figure 18 shows in plan and side elevation, details of the goods tray carrier frame fitted to the handlebars of a bicycle. In the plan view the tray is omitted for clarity. Referring to the drawings listed above, the following is a complete inventory of all parts shown numbered thereon. Against some parts there is included a brief description of their function, which is intended as an aid to understanding the more detailed descriptions of the embodiment :- 10 Moulded seat shell 11 Harness, with load transference to five strong-points on the foldable frame. 12 Side rod (front) 1 off each side. 13 Side strut (rear) 1 off each side. 14 Radius rod (trapeze assembly) 1 off each side. 15 Side rod (pushing handle) 1 off each side. 16 Twin-wheel assembly 4 off. 17 Brake assembly 2 off. 18 Side-plate moulding, with aperture for car seat belt 1 off each hand. 19 Hand-grip 2 off. 20 U-section bracket 2 off. 21 U-section bracket 2 off. 22 Cleat, for securing car seat belt (of known design) 2 off 23 Transverse tube (upper) 24 Transverse tube (lower) 25 Transverse tube (locking latch) 26 Capped clench washer 27 Transverse tube (pushing handle) - secured by tie rod and locking nuts. 28 Transverse torque tube (part of trapeze assembly) 29 Tie rod (secures tubes 23 & 24) - with locking nut and capped clench washer 2 off 30 Locking latch 1 off each hand. 31 Locking latch striker bush, with screw and locking nut 1 off each side. 32 Locking nut (nylon insert type) 33 Pivot rod - with capped clench washer (Pivot "D") 34 Spring retaining pin - with groove for spring location 1 off each side. 35 Tension spring 1 off each side. 36 Diagonal channel - for mounting seat moulding 1 off each hand 37 Front hook 1 off each side 38 Rear hook (part of trapeze assembly) 1 off each side. 39 Transverse member (rear) - seat-mounting chassis of pushchair 40 Transverse member (front) -seat-mounting chassis of pushchair Transverse bar (front) - carrier rack on bicycle Transverse bar (centre) - carrier rack on bicycle Transverse bar (rear) - carrier rack on bicycle Side rail - carrier rack 1 off each side. Safety latch Longitudinal bars 1 off each side. Mounting block (attaches bars 46 to bicycle frame) Support strut 1 off each side. Steadying strut 1 off each side. Clamping fishplate 1 off each side. Mounting plate 1 off each side. Support plate - safety latch 1 off each side. Wheel guard Headrest assembly Headrest support bar 1 off each side. Goods tray Tray rear support bracket 1 off each hand. Tray front support hook 1 off each side. Attachment fitting for tether strap Spacer tube Square-section plug Round-section plug Spacer bush - Pivot "A" 1 off each side. Spacer washer 2 off Attachment fitting for shopping bag 1 off each side. Plastic inserts for self-tapping screws Self-tapping screws Tether strap assembly Tether strap anchorage (on car) Lap strap (part of lap/diagonal harness assembly in car) Shoulder strap (part of 70 above) Seat back (part of car) Seat bottom (part of car) - shown hinged forward Gusset plate (part of trapeze assembly) 1 off each side Carrier frame for tray 76 Bracket for attachment of strut 77 77 Adjustable-length strut 78 Retaining pin 79 Reflector mounting (normally part of bicycle) 80 Spring clip 1 off each side. 81 Elasticated retaining net 82 Net attachment rods 2 off. Referring to the drawings, Fig 1 shows a child's moulded bicycle seat shell 10 and a harness 11 which satisfies the requirements of BS 3254. The seat is mounted in a foldable pushchair frame shown expanded in Figs 1 and 2, and folded in Figs 3 and 4. The frame comprises side rods 12 and 13, which are preferably of tubular cross-section. Attached to the lower ends of these side rods are wheel assemblies 16, of known design, and the rear wheel assemblies each incorporate a brake assembly 17, also of known design. The seat shell 10 is attached to a chassis frame comprising transverse members 39 and 40 and two diagonal channels 36, as shown in Figs 2 and 13, and this assembly is supported by side-plates 18, which are in turn attached to side rods 12, as shown in Fig 9. To the upper end of each side rod 12 there is attached a bracket 20, which is of U-shaped cross-section. Side rods 15, which form part of the pushing-handle assembly, are pivotally mounted at "A" to brackets 20, and to side rods 15 there are attached brackets 21, which are also of U-shaped cross-section. Pivotally mounted at "B" to brackets 21 are the upper ends of side struts 13. The foregoing details are best shown in Figs 1 and 16. Close to their lower ends, side struts 13 are pivotally attached at "C" to the radius rods 14, which form part of a trapeze-like assembly which pivots about axis "D" of a transverse torque tube 28. The trapeze assembly is pivotally attached to the side- plates 18 by means of pivot rod 33, and secured by capped clench washers 26. The trapeze assembly is best shown in Fig 12. Referring to Figs 14 and 16, it will be seen that there is, coaxial with pivot "A", a lower transverse tube 24, and also an upper transverse tube 23, with its axis at "F". Pivotally mounted at X F" are locking latches 30, one at each side, and joined together by a transverse tube 25. Each latch is constrained in the "locked" position by a spring 35, which engages with a striker bush 31 which also forms part of the attachment of bracket 21 to rod 15. Referring to Figs 14 and 16, it will be seen that the holes in bracket 20 are counterbored on both sides of the bracket. On one side the ends of transverse tubes 23 and 24 are inserted into the counterbores, and on the other side the locking nuts 32 which secure the tie-rods 29 are located in the counterbore recesses. Figs 14 and 16 show the protruding part of these locking nuts having attached to them capped clench washers 26 of a size which will firmly grip the circular boss which surrounds the nylon inserts of the locking nuts. This feature provides protection from the protruding end of the tie rod and imparts a pleasing appearance . The pushchair frame is folded in the following sequence :- Transverse tube 25 is lifted against the tension of springs 35, so disengaging locking latch 30 from striker bush 31. Using the other hand to grip transverse tube 27 (see Fig 1) , the pushing handle assembly is swung rearwards and downwards until it ends up adjacent and parallel to side struts 13 (see Figs 3 and 4) . To extend the pushchair frame the above operation is reversed. The frame will automatically lock in the extended condition due to the sprung action of latches 30. In the event that the latches should fail to engage, the weight of the child will assist in maintaining the pushchair frame in its extended condition, thereby constituting a "fail-safe" feature . The frame is kept in its folded condition by virtue of a sprung detent action, which requires the operator to apply an increasing amount of force to the pushing handle assembly in the final phase of folding. Similarly, an increased amount of force is required to release the handle assembly in the initial phase of extending the frame. This detent action is caused by the geometric design of the frame folding mechanism, and is best understood by reference to Fig 8:- Referring to Fig 8, movement of the pushing handle 15 in an anti- clockwise direction about pivot point "A" causes the rear strut 13 to move the radius rod 14 in an anti-clockwise direction about pivot "D" until, at approximately its mid-point, strut 13 strikes a stop "E" (an abutment at the end of cleat 22) . At this juncture, pivot "B" has reached position "Bl", and further rotation of the pushing handle 15 causes strut 13 rotate in a clockwise direction about pivot "Cl" until pivot "B" reaches position "B2". It will be seen that the arc Bl - B2 described by strut 13 as it rotates clockwise, is different from the arc Bl - B2 described by handle 15 as it rotates anti-clockwise. In actual practice, point "B" is forced to follow an intermediate path while travelling from Bl to B2, causing slight elastic deformation of the pushchair framework. The reactive force so produced causes the detent effect whereby an increased force is required to lock or to release the pushchair folding mechanism when it is in its folded condition. This detent effect is also used to advantage when locking the pushchair to the carrier rack on a bicycle, and this aspect of the present invention will now be described in detail :- Fig 5 shows the carrier rack attached to a bicycle, in which longitudinal bars 46 are curved at their forward end to plug into a mounting block 47, of known design. Transverse bars 41, 42 and 43 attach to the longitudinal bars 46 by means of welded plates 51 and 52. Preferably all bars are of tubular cross- section for reasons of lightness. Joining the ends of bars 42 and 43 are side rails 44. Support struts 48 and steadying struts 49 are perforated at their lower ends with holes spaced at regular intervals. Any convenient pair of holes in struts 48 can be used as pick-ups for clamping bolts which pass through similarly-spaced holes in clamping fishplate 50. The purpose of the spaced holes in struts 48 and 49 is to allow for variations in size and shape of the frames of different makes of bicycles. A curved wheel guard 53 is attached to struts 48 and 49, and also serves as a mudguard. A safety latch 45 serves as a double-locking device when the pushchair is mounted on the rack, and its function will be described later. Fig 9 shows, in cross-section, the seat mounting chassis which forms part of the pushchair frame. Radius rod 14 is shown in the position it adopts when the frame is in its extended condition, prior to mating with the carrier rack on the bicycle. Two front hooks 37 are permanently attached to the front ends of the diagonal channels 36 which form part of the seat mounting chassis, and two hooks 38 are permanently attached to the torque tube 28 which, together with radius rods 14, forms part of the trapeze assembly. Fig 10 shows, in cross-section, the pushchair seat mounting chassis mounted and locked onto the carrier rack on the bicycle. The procedure for achieving this is described in the following sequence:- With the pushchair in its normal operating condition (ie: extended), and either with or without a child seated and harnessed in it, the pushchair is lowered onto the carrier rack with its front wheels straddling the narrow part of the carrier forward of transverse bar 42 (see Fig 5) . The pushchair is then slid backwards until hooks 37 engage with the front transverse bar 41 of the carrier rack. This can be checked visually as bar 41 is clearly visible between the two hooks 37. Then, with the pushchair now resting on carrier side rails 44, release latches 30 by lifting tube 25, and fold the pushchair in the manner already described. Reference to Fig 10 shows that, in folding the pushchair, the torque tube 28 is caused to rotate in an anti-clockwise direction until the hooks 38 engage with the rear transverse bar 43 of the carrier rack, so locking the pushchair to the carrier. As a double security, latch 45 should be engaged with the transverse bar 27 of the pushing handle assembly, thus preventing any inadvertent unfolding of the pushchair and consequent unlocking from the carrier rack. Latch 45 is so positioned that it will only engage with the bar 27 if the initial locking operation has been safely completed (ie: the hooks 38 have successfully engaged with bar 43) . To remove the pushchair from the carrier, the reverse sequence is carried out. Fig 7 shows the folded pushchair installed in a car. Installation and removal may be carried out either with or without a child seated and harnessed in it. However, before folding the pushchair the brakes should be applied, and the goods tray and the contents of the shopping bag must be removed and stored safely - preferably in the boot space of the car. The bottom of the car's rear seat must then be lifted and hinged forward, as shown in Fig 7. The pushchair is then folded and lifted into the car, ensuring that it stands on its rear wheels, with its back hard against the car seat back 72. The tether strap 68 may then be connected to the attachment fitting 59 at the top of the pushchair frame by engaging the "dog-lead" clip 68, as shown in Fig 15. The 3-point lap/diagonal harness 70/71 (which forms part of the car) is pulled out to its full extent, against the tension of its inertia reel. The buckle tongue fitting is then passed through the triangular apertures in side plates 18, and fastened to the buckle quick-release receptacle on the car. The lap portion 70 of the harness is then tightened by pulling hard on the diagonal portion 71. Once tight, the diagonal portion 71 is fed into cleat 22 and any remaining slack allowed to wind back into the inertia reel. Fig 17 shows a goods tray 56 in plan and side elevation. The side elevation shows the tray installed on the pushchair, whereby two hooks 58, which are attached to the tray, engage with existing slots in the footwells of the seat shell moulding 10. The rear end of the tray is supported by brackets 57, which are attached to the tray and rest on the lower ends of radius rods 14 of the trapeze assembly. Installing or removing the tray involves simply engaging or disengaging the hooks from the slots in the seat shell 10. Fig 18 shows the method of stowing the goods tray and its contents on a carrier frame 75 attached to the handlebars of a bicycle by means of clips 79 and a strut 78, which is of adjustable length to allow for variations in handlebar height. The tray 56 is located in frame 75 and retained (with or without contents) by means of an elasticated net 80. Opposite edges of the net are attached to rods 81, of which the forward one is fixed to the frame 75 by means of Λ P' -section brackets. The rod shown hanging free engages with brackets 82, which are of inverted V -section, when the net is stretched over the tray and any loose goods contained therein.

Claims: CLAIMS 1. A pushchair comprising a moulded seat shell mounted on a frame, said frame being moveable between a first folded configuration and a second extended configuration, the frame having means for releasably securing it to a carrier rack on a bicycle. 2. A pushchair as claimed in Claim 1 wherein the frame comprises a number of transverse members for supporting the seat shell, a pushing-handle assembly having a pair of pushing-handle rods, a lower rear part, a pair of front side members connected by a first transverse member, and a pair of rear side members. 3. A pushchair as claimed in Claim 1 or Claim 2 wherein the frame has a number of transverse members for at least partially supporting the seat shell, and no additional transverse members lower than those which at least partially support the seat shell, thereby enabling the pushchair to straddle the rear wheel of a bicycle in both folded and extended configurations. 4. A pushchair as claimed in any of Claims 1 to 3 wherein a lower rear part of the frame is maintained in a rigid condition by means of a trapeze-like frame member comprising a pair of radius arms rigidly attached to each end of a transverse torque tube, said transverse torque tube being pivotable about a long axis. 5. A pushchair as claimed in Claim 4 wherein the transverse torque tube has, rigidly attached to it, first hook-like projections which, when the frame is secured to the carrier rack on a bicycle, engage with a transverse member at the rear of the carrier rack. 6. A pushchair as claimed in Claim 4 or Claim 5 wherein the trapeze-like frame member operates in conjunction with other members of the frame to form a geometric lock when the frame is in its folded configuration. 7. A pushchair as claimed in Claim 6 in which the geometric lock maintains the hook-like projections engaged with the transverse member at the rear of the carrier rack. 8. A pushchair, as claimed in Claim 6 or Claim 7 in which the geometric lock is maintained by a force derived from the elastic deformation of members of the frame. 9. A pushchair as claimed in claim 8 wherein the elastic deformation of the members of the frame is caused by a resultant force which is the combination of a first force component and a second force component, both of which act at a point where the pushing-handle assembly and the rear side member are pivotally joined. 10. A pushchair as claimed in claim 9 wherein the first and second force components are produced due to a discrepancy between a first natural arc described by the pushing-handle assembly and a second natural arc described by the rear side member. 11. A pushchair as claimed in any of Claims 8 to 10 wherein the elastic deformation increases towards the latter part of the folding action. 12. A pushchair as claimed in any of Claims 4 to 11 preceding claim, in which the long axis of the pivotable transverse torque tube is maintained in a constant position relative to the front side members of the foldable frame by means of side plates rigidly attached to the front side members. 13. A pushchair as claimed in Claim 12 in which the side plates also support a chassis frame for at least partially carrying the load from the moulded seat shell. 14. A pushchair as claimed in Claim 13 in which the chassis frame has attached to it second hook-shaped fittings which, when the frame is secured to the carrier rack on a bicycle, engage with a transverse member at the front of the carrier rack. 15. A pushchair as claimed in Claim 14 in which the second hook- shaped fittings at the front, together with the first hook- like projections, firmly secure the folded pushchair to the carrier rack. 16. A pushchair as claimed in any preceding Claim in which there is provided an additional safety latch attached pivotally to the carrier rack on the bicycle, so that when the frame is in its fully-folded configuration the safety latch engages with a further transverse member, said further transverse member being attached between the pushing-handle members of the foldable frame. 17. A pushchair as claimed in Claim 16 in which the additional safety latch can only engage with the transverse member between the pushing-handle members when the geometric lock has been correctly and successfully completed. 18. A pushchair as claimed in any preceding claim, wherein the transverse members of the foldable frame comprise tubular struts through which tie rods pass for the purpose of securing the side members, the tie rods being secured by locking nuts. 19. A pushchair as claimed in Claim 18 wherein the locking nuts securing the tie rods have a circular boss onto which is attached a capped clench washer. 20. A pushchair as claimed in Claim 2 or 16 wherein a safety harness is provided, the safety harness having shoulder straps attached one of the first transverse member or the further transverse member. 21. A pushchair as claimed in claim 20 wherein the shoulder straps of the safety harness are attached to the first transverse member. 22. A pushchair as claimed in Claim 20 wherein the shoulder straps of the safety harness are attached to the further transverse member. 23. A pushchair as claimed in any preceding Claim, having means for releasably securing the frame, in its folded configuration, to the inside of a car. 24. A pushchair as claimed in Claim 12 to 23 wherein the side plates are each provided with a slot through which the lap- and-diagonal seat belt of a car may be passed in order to secure the pushchair within a car. 25. A pushchair as claimed in Claim 23 or 24 wherein, adjacent to each slot, there is provided a clamping device to secure the diagonal portion of the car seat harness, thereby maintaining the tension of the portion of the belt which passes through the slots. 26. A pushchair as claimed in any of claims 23 to 25 wherein there is additionally provided a means of securing the upper end of the folded pushchair to the car body by using a tether strap. 27. A pushchair as claimed in Claim 26 in which the tether strap is connected to a fitting attached to the further transverse member of the pushchair frame. 28. A pushchair as claimed in any preceding claim in which there is provided a removable tray for the carriage of goods. 29. A pushchair as claimed in Claim 28 in which the tray may be attached to the pushchair by means of hooks at a front end engaging with slots in foot-wells provided in the seat moulding, and brackets at a rear end of the tray, arranged such that they rest on the sloping lower ends of the radius arms of the trapeze-like member. 30. A pushchair as claimed in Claim 28 or Claim 29 in which the tray and its contents may be carried on a separate rack mounted on the handlebars of the bicycle. 31. A pushchair as claimed in Claim 30 in which the rack is provided with releasable clips to attach it to the handlebars, and a releasable strut to support its front edge. 32. A carrier rack for a bicycle for use with the pushchair of any preceding claim. 33. A pushchair substantially as described herein with reference to the accompanying drawings: Figures 1 to 18.

Inventors: LONGLEY TIMOTHY JOHN RICHARD, LONGLEY, TIMOTHY, JOHN, RICHARD
Applicants: LONGLEY TIMOTHY JOHN RICHARD, LONGLEY, TIMOTHY, JOHN, RICHARD
Application year: 2001
Main classification: B62B7
IPC codes: B60N2, B62B7, B62J1