GB2204282A - Folding infant carriage - Google Patents

Abstract

The carriage has a wheeled undercarriage (10), side support assemblies (22) having lower sections (28) whose lower ends are pivoted to the front of the undercarriage, and upper sections (26) joined at their top ends by a handle. The upper sections can slide longitudinally of the lower sections to retract and extend the support assemblies, catches (46) retaining said assemblies in the extended condition. A seat (44) or other load-carrying cradle formation such as a carry-cot body is carried on mountings (40) located by intermediate portions of the support assemblies, preferably with limited sliding movement therealong during folding or unfolding of the chair to align the seat or other load-carrying cradle formation with the undercarriage when fully folded, and strut means (24) pivoted between the rear end of the undercarriage and the upper sections of the support assemblies to determine the angular relationship between the latter and the undercarriage in the erected condition with the upper sections extended. On retraction of the upper sections, the strut 24, cradle, and retracted side support assemblies are folded down onto the undercarriage. A wheel braking arrangement is provided which is automatically actuated on erection of the carriage. <IMAGE>

Description

Folding Infant Carriage This invention relates to folding carriages for infants of the kind commonly known has push-chairs or baby buggies and has as its object the provision of a folding infant carriage which is convenient, easy and safe to operate and use; strong and durable; and of neat appearance.

According to the invention there is provided a folding infant carriage including an undercarriage having fore and aft ground engaging wheels; a pair of spaced parallel elongate side support assemblies having lower sections whose lower ends are pivotedly attached on a common axis to a fore end portion of the undercarriage, upper sections guided for sliding movement longitudinally of the lower sections whereby the effective length of the support assemblies can be selectively changed between retracted and extended conditions, the upper ends of the upper sections serving as or mounting handle means for propulsion or other handling of the carriage, and releasable securing means for retaining the sections in the extended condition; a load carrying cradle formation operatively secured between and supported by intermediate portions of the support assemblies and forming or adapted to mount a seat, cot or the like in which an infant may travel; and strut means pivotedly attached between and aft end portion of the undercarriage and said upper portions of the support assemblies to determine the angular relationship between the undercarriage and said assemblies so that with the latter in extended condition the carriage is unfolded with the cradle formation supported in spaced relationship above the undercarriage; the carriage being folded by retracting the support assemblies to bring the cradle formation, strut means and said assemblies into close proximity with each other and with the undercarriage.

Preferably mountings of the cradle formation are slidingly located on said intermediate portions being trapped at an upper location when the support assemblies are in extended condition but being freed for limited downward displacement along said assemblies when they are moved to the retracted condition to align the cradle formation with the undercarriage as the carriage is folded.

It is also preferred that braking mechanism acting on one or more of the wheels (preferably at least all the wheels at one end of the under carriage) is set automatically in an on condition as the carriage is unfolded, e.g. by being linked for actuation in response to relative angular movement between the strut means and the undercarriage.

It is further preferred that the securing means of the support assemblies includes a primary interlock having interengagable formations on the upper and lower sections which can be positively interlocked to prevent any sliding movement of the sections from the extended condition, and also a secondary interlock consisting of formations which automatically snap engage as the sections reach the extended condition to prevent collapse before the primary interlock has been secured.

Conveniently at least some of the wheels will have a castor action to facilitate steering of the carriage in use and such wheels may be provided with selectively engaging steering locks to disable the castor action and keep all the wheels in line as when pushing the carriage over rough, uneven or soft surfaces.

An example of the invention is now described with reference to the accompanying drawings wherein Figure 1 is diagrammatic side elevation of a folding infant carriage in unfolded condition ready for use; Figure 2 is a detail showing securing means on part of a side support assembly; Figures 3 and 4 are further side elevations showing successive stages in the process of folding the carriage; Figure 5 is a side elevation of braking mechanism of the carriage; and Figure 6 is a vertical sectional view of a steerable wheel assembly of the carriage.

The carriage will first be described in its fully erected or unfolded condition standing on its wheels as shown in Figure 1. It is to be understood that the side elevations of Figures 1,3 and 4 show the members making up one side only of the carriage which are in fact duplicated on its other side rigidly joined by cross-members not readily visible.

The carriage comprises an undercarriage indicated generally at 10 comprising a pair of tubular horizontal chassis members 12 extending fore and aft and provided with downturned end portions locating respective sets of fore and aft ground engaging wheels 14,16 further described hereafter.

members 12 are connected by fore and aft cross-rods 18, 20 to form a rigid frame which may conveniently locate a wire mesh basket or other tray (not shown) for shopping or other articles.

A pair of side support assemblies indicated generally at 22 have their lower ends pivoted on the fore cross-rod 18 inwardly of members 12.

Assemblies 22 extend upwardly and rearwardly at an angle to undercarriage 10 determined by a pair of tubular struts 24 whose lower ends are pivoted on the aft cross-rod 20 and whose upper ends are pivotedly attached to assemblies 22 thus forming a pair of triangular side frames. Struts 24 are end parts of a common length of tube being united by a horizontal cross portion 25 at the aft end of undercarriage 10.

Support assemblies 22 will now be described in greater detail. They have upper and lower tubular sections 26,28 located on close-coupled parallel axes by upper and lower guide blocks 30,32 the upper blocks 30 being fast with the upper ends of lower sections 28 but having apertures for free sliding movement of the upper sections 26, and the lower blocks 32 being fast with the lower ends of said upper sections but being apertured for sliding movement along lower sections 28 thus the effective length of the support assemblies 22 can be varied within predetermined limits as if their sections were telescopically engaged while maintaining the rigidity of the assemblies with respect to lateral forces.

The two parallel upper sections 26 are again end parts of a common length of tube, being united by a horizontal cross portion at the upper end serving as a handle 34 for propelling the erected carriage or lifting or other handling of it e.g. when folded.

Similarly the two lower sections 28 are also end parts of a common length of tube united by a intermediate horizontal cross portion (not shown) across the fore end of undercarriage 10 and, conveniently, a foot rest 36 has its inner end mounted rigidly on or immediately above this cross portion.

With assemblies 22 in the extended condition shown in Figure 1 the guide blocks 30, 32 are spaced apart at the intermediate portions of the assemblies by, in this example, about 150mm.

Trunnions 39 fixed to the lower periphery of upper sections 26 between blocks 30 and 32 form the upper pivotal connections of the struts 24. A pair of elongate slide blocks 38 are held captive between blocks 30 and 32 in the gap between the parallel portions of sections 26, 28. A pair of pivotal mountings 40 are located on the opposing inner faces of blocks 38 and these in turn locate a load carrying cradle formation being, in this example, the tubular frame 42 (shown in broken lines) of a push chair type seat 44 which is of generally conventional design and which will include the usual safety harness. The angle of the seat 44 with respect to the side frames of the carriage can be varied in known manner in that the pivotal mountings 40 are each in two parts formed as serrated clutch disks which can be axially disengaged by toggle levers positioned on the outer faces of the slide blocks 38.

When the carriage is to be folded frame 42 will be aligned in generally co-planar relationship with assemblies 22 and, for clarity, the seat and its frame have not been shown in Figures 3 and 4.

It is to be understood that other load carrying bodies and/or frames may be interchangeably substituted either on a common cradle formation or by engagement with the pivotal mountings 40; for example, a frame for supporting a carrycot body or an integral perambulator body may be used for small babies.

To secure assemblies 22 positively in their extended condition releasable securing means are provided, in this example comprising both primary and secondary interlocks.

The primary interlock comprises a pair of locking tabs 46 which are pivoted on short end portions of the lower sections 28 which project beyond the upper guide blocks 30. Tabs 46 are blocks of a resilient plastics material and include part-cylindrical hollows which can be snap engaged with the periphery of the upper sections 26, further positive location being provided by location pegs 48 projecting from said periphery to co-act with a grooved portion of each respective tab.

A secondary or safety interlock is also provided on the right hand upper guide block 30 only (Figure 2) in the form of a hook shaped catch 50 carried on a resilient tongue being a unitary part of block 30. Catch 50 co-acts with a further locating peg 52 projecting downwardly from the periphery of upper section 26 when the support assemblies are fully extended. Catch 50 is resiliently loaded to snap engage with peg 52 giving an audible click as soon as the sections reach extended condition, thus they are automatically secured against any accidental sliding back or collapse before the primary interlock is secured or even if the latter should be forgotten.This is a valuable safety feature as it is often necessary for a mother to erect the pushchair using one hand while holding the infant with the other hand and the infant may often have to be placed in the seat before the mother may have chance to complete the securing process. Further security is provided by arranging that the right hand tab 46 co-acts with the upwardly extending operating limb of catch 50 when secured so that the latter cannot be operated or released while tab 46 is in place.

Folding the carriage will now be described with reference to the sequence illustrated in Figures 3 and 4.

Figure 3 shows an initial stage in which, following release of the securing means i.e. tabs 46 having been swung out of engagement with upper section 28 and the catch 50 having been sprung clear of peg 52, handle 34 is pushed. downwards to slide upper sections 28 along the lower sections. In this initial movement the struts 24 are moved angularly downwards until they extend normally of the support assemblies and the spacing between blocks 30 and 32 has been increased allowing the slide blocks 38 carrying the mountings 40 to follow the lower blocks 32 downwards. Longitudinal grooves in the parts of all the blocks which slide along the tube peripheries permit passage of the locating pegs 48 and 50.

The downward movement of the handle is contined until the support assemblies take up the retracted condition shown in Figure 4, the struts 24 now forming an acute angle with the undercarriage.

Before this position is reached the downward movement of the seat carrying slide blocks 38 has been halted by stop-pegs 54, this downward movement bringing the seat frame 42 into alignment with the chassis frame of undercarriage 10.

The position of struts 24 now permits the final stage of folding in which the fully retracted side assemblies swing downwards with at least their lower ends lying between the chassis members 12, the struts 24 also lying substantially between those members and the seat 44 nesting within the undercarriage. A clip or clips, e.g. on the undercarriage may be provided to retain the side assemblies in the folded position, the handle now lies adjacent to the aft end of the undercarriage enabling the folded carriage to be picked up.

During the final stages of folding the foot rest 36 will have pivoted upwards to the position shown in broken lines in Figure 4 and the folded carriage may be stood upright on its fore end with the outer edge of the foot rest serving as a support together with the fore wheels 14.

Unfolding and erecting the carriage is carried out by reversing the process, to assist this a foot may conveniently be placed on the cross portion 25 of the strut tube to hold the undercarriage down while handle 34 is being pulled upwardly and outwardly.

Brake mechanism of the carriage will now be described with reference to Figure 5. The carriage is provided with two aft wheels 16, which are nonsteerable, they are pivoted on a common cross axle shaft 56 mounted in resilient cranked blocks 58 to give a degree of springing, these blocks being mounted on the rear downwardly directed ends of the chassis members 12. As is required by current regulations the brake acts on both these rear wheels, the aft cross rod 20 being rotatable or including a rotatable sleeve to serve as a brake cross shaft. Rigid extensions on rod 20 project outwardly beyond members 12 and are bent generally rearwardly and then inwardly again to form braking members 60 which can be urged angularly into engagement with the peripheries of the wheels 16.A forwardly extending foot pedal lever 62 is welded to the righthand outer end of shaft 20 for angular movement of the latter to release or set the brake.

Snap-over brake engaging means is provided comprising an elongated closed loop 64 of metal rod welded fast with the brake cross shaft adjacent the inner face of the right hand strut 24. Loop 64 is positioned so that a major part of the length of the slot defined thereby extends forwardly of rod 20 with only a minor part extending rearwardly thereof.

A runner 66, conveniently a link assembly of a standard roller bicycle chain is engaged with loop 64, a roller of said chain permitting free low friction movement under loading from end to end of the upper longitudinal side of the loop. A tension spring 68 links runner 66 with an anchorage in the form of an aperture in the side wall of strut 24 spaced upwardly from rod 20.

Loop 64 is somewhat inclined so that its forward end is uppermost with the brake set in the ON position shown in full lines in Figure 5, thus the tension of spring 68 urges runner 66 to the forward end of loop 64 to exert maximum leverage keeping the braking inembers 60 clamped against the wheel 60.

When the brake is to be released pedal lever 62 is pressed downward so 20 freeing the braking members 60 from the wheels and at the same time pivoting loop 64 anticlockwise as viewed in Figure 5 to the position shown in broken lines. This movement causes the loop to slope in the opposite direction with respect to the spring anchorage so that the spring tension snaps runner 66 along the loop to the rear end where it retains the brake in its OFF condition. Because the spring is exerting a much less degree of leverage on rod 20 at this off position a small force on pedal lever 62 will be sufficient to displace the loop 64 for the runner 66 to snap over-centre and the spring will then immediately exert the maximum leverage applying the brake once more.

As the spring anchorage is on strut 24 which is angularly displaced with respect to cross rod 20 and hence the loop 64 when the carriage is unfolded the brake will always be applied automatically and fully as unfolding is completed. It will be seen that the spring anchorage moves through the arcuate path indicated by the arrow on Figure 5 during folding which ensures, even if the brake was off at the time, that runner 66 is pulled to the front end of loop 64 (although, as the spring is substantially in line with the loop with the carriage folded the brake will not then be applied). During unfolding the angular movement of strut 24 increased the spring tension acting on the forward end of loop 64 so applying the brake fully.This is another valuable safety factor in ensuring that the carriage cannot run away e.g. on a slope or kerb before a mother has chance to apply the brake herself and while she may be trying to place the infant in the carriage.

The mounting and operation of the fore wheels 14 will now be described with reference to Figure 6.

Two close coupled pairs of wheels 14 are each carried on a common short axle 66 carried in respective cranked resilient blocks 68 similar to blocks 58, however each block 68 is in turn carried on a short vertical pivot shaft 70 rotatable within a bearing sleeve 72 within the downwardly directed fore end of each chassis member 12.

An upper end part of each shaft 70 has a reduced diameter neck 74. On assembly shaft 70 is inserted into sleeve 72 and is then retained captive in the end of member 12 by means of a rivet or other fastening 76 secured in the tube wall in alignment with neck 74, this also serving to secure the sleeve 72.

The upper end face of shaft 70 is domed and abuts a cross pin 76 which extends diametrally through the tube end portion. One end of pin 76 is headed and is acted on by a compression spring 78 while its other end portion is cranked downwardly and then inwardly to bring the free end into alignment with a second bore through one wall of the tube, a blind bore 80 in shaft 70 aligning therewith when wheels 14 are in a straightahead position. Pin 76 can be swung into engagement with blind bore 80 and will be retained therein by the action tf spring 78 to keep the wheels in the straightahead position to facilitate travelling over rough, uneven or soft surfaces. Pin 76 can be withdrawn and swung so that its end is not engaged in the tube and shaft bores when the normal castor action is required.

Claims (16)

1. A folding infant carriage including an undercarriage having fore and aft ground engaging wheels; a pair of spaced parallel elongate side support assemblies having lower sections whose lower ends are pivotedly attached on a common axis to a fore end portion of the undercarriage, upper sections guided for sliding movement longitudinally of the lower sections whereby the effective length of the support assemblies can be selectively changed between retracted and extended conditions, the upper ends of the upper sections serving as or mounting handle means for propulsion or other handling of the carriage, and releasable securing means for retaining the sections in the extended condition; a load carrying cradle formation operatively secured between and supported by intermediate portions of the support assemblies and forming or adapted to mount a seat, cot or the like in which an infant may travel; and strut means pivotedly attached between and aft end portion of the undercarriage and said upper portions of the support assemblies to determine the angular relationship between the undercarriage and said assemblies so that with the latter in extended condition the carriage is unfolded with the cradle formation supported in spaced relationship above the undercarriage; the carriage being folded by retracting the support assemblies to bring the cradle formation, strut means and said assemblies into close proximity with each other and with the undercarriage.

2. A carriage as in Claim 1 wherein the cradle formation is carried on mountings which are slidingly located on said intermediate portions of the support assemblies, being trapped at an upper location when the support assemblies are in their extended condition, but being freed for limited downward displacement along said intermediate portions when the support assemblies are moved to the retracted condition so aligning the cradle formation with the undercarriage as the carriage is folded.

3. A carriage as in Claims 2 wherein the support assemblies include upper and lower guide blocks locating said upper and lower sections in close-coupled parallel relationship, the upper guide blocks being fast with the upper ends of the lower sections but having apertures for free sliding movement of the upper sections, and the lower blocks being fast with the lower ends of said upper sections but being apertured for sliding movement along said lower sections, said mountings of the cradle formation locating between said upper and lower guide blocks.

4. A carriage as in any preceding claim wherein said upper sections of the support assemblies are guided for sliding movement along the rear or underside of the lower sections.

5. A carriage as in Claim 4 wherein said strut means is pivotally attached to the upper sections between the upper and lower guide blocks.

6. A carriage as in any preceding claim wherein the securing means of the support assemblies includes a primary interlock having inter-engageable formations on the upper and lower sections which can be positively interlocked to prevent sliding movement of the sections -from the extended condition, and also a secondary interlock consisting of formations which automatically snap-engage as the sections reach the extended condition to prevent collapse before the primary interlock has been secured.

7. A carriage as in Claim 6 wherein the primary interlock comprises a pair of locking tabs each pivoted on a portion of one of said sections and each including a hollow for resilient snap engagement with the adjacent periphery of the other of said sections to prevent relative sliding movement between the sections.

8. A carriage as in Claim 6 or 7 wherein the secondary interlock is a hook-shaped catch resiliently mounted on one said section to co-act with a locating peg projecting from the other of said sections when the support assemblies are fully extended, the catch being resiliently loaded to snap-engage with the peg.

9. A carriage as in any preceding claim including braking mechanism acting on at least one of the wheels which is set automatically in an on condition as the carriage is unfolded.

10. A carriage as in Claim 9 wherein said braking mechanism acts simultaneously on all the wheels at one end of the undercarriage.

11. A carriage as in Claim 10 wherein said brake acts on the aft wheels.

12. A carriage as in Claim 11 wherein the braking mechanism is linked for actuation in response to relative angular movement between the strut means and the undercarriage.

13. A carriage as in any preceding claim wherein at least some of the wheels have a castor action to facilitate steering of the carriage in use.

14. A carriage as in Claim 13 wherein the fore wheels have said castor action.

15. A carriage as in Claim 14 or 13 including selectively engageable steering locks to disable the castor action and keep all the wheels in line.

16. An infant carriage substantially as hereinbefore described with reference to and as shown in the accompanying drawings.