Field of the Invention [0001 ] The invention relates to a buckle for fastening together the straps of a seat harness. In particular, the invention relates to a buckle for a child restraint harness fitted to a car seat, high chair, stroller or the like.

Background of the Invention

[0002] Safety harnesses are generally fitted to seats specifically intended for use by children such as highchairs, child car seats and strollers or 'pushchairs'. Many of these harnesses typically have five straps and are referred to as a 5 point safety harness. The straps are positioned such that one strap extends over each shoulder, one strap from each side of the child's lap and either a single or double crotch strap extending downwardly between the child's legs. The five straps are secured together at a central buckle that positions on the stomach or lap of the child when the harness is done up.

[0003] To comply with applicable Standards, harnesses used in vehicle child seats should have a quick-release buckle so that a parent or carer can quickly release and easily free the child from the restraint in case of emergency, yet the buckle operating mechanism must be such as to prevent a child from easily opening it.

[0004] To guard against a child being able to easily open vehicle harness buckles that position in the lap of a child when fitted, many buckles are designed with a push button that requires considerable force to disengage the straps from the buckle. However if the child is particularly strong and/or determined, the buckle may be still be opened. Increasing the actuation force required to disengage the straps from the buckle tends to make the harness generally more difficult to use for the parent or guardian, particularly if the child tends not to sit still or cooperate when buckling or unbuckling the harness.

Summary of the Invention

[0005] With the above issues in mind, the present invention provides a buckle for a seat harness, the buckle comprising: a clasp and at least one detachable strap anchor for detachably securing a harness strap to the clasp, the clasp and the detachable strap anchor having complementary formations that engage to secure the strap anchor to the clasp and can be disengaged to release the strap anchor from the clasp; and a release actuator mounted to the clasp for

disengaging the complementary formations; wherein, the release actuator is movable relative to the clasp in such manner that a predetermined sequence of at least two movements in different directions must be performed in a specified order to disengage the complementary formations.

[0006] By configuring the buckle to release the straps only in response to a specified series of actuator movements, children are far less likely to discover the required opening procedure through their normal investigations of the buckle. Because of this, the release actuator could be mounted to the clasp without biasing elements against which actuation / movement of the actuator at the clasp is to be performed, thus facilitating ease of use. [0007] However, the buckle will advantageously comprise at least one biasing element operative on the actuator such that each movement in the predetermined sequence is against a bias. By ensuring each movement in the sequence is against a bias, the release actuator will always return to a start position so that the full sequence is required each time to release the buckle, which improves safety against unintended release when a child is playing with the buckle.

[0008] Preferably, the complementary formations comprise a fixed snib and a flexible hasp with a hasp aperture to receive the snib for mutual engagement, wherein the release actuator is arranged to flex the hasp to remove the snib from the hasp aperture during a final movement in the predetermined sequence of at least two movements.

[0009] Preferably, the clasp has a ring-shaped body with a central cavity in which the release actuator is movably mounted and at least one side aperture for receiving the hasp of the at least one strap anchor. The snib is fixed to the ring shaped body proximate the side aperture such as to cause the hasp to elastically flex whilst in sliding contact with the snib during insertion into the side aperture and come to rest within the hasp aperture upon the hasp elastically resuming its normal position, thereby securing the strap anchor to the buckle.

[0010] Preferably, the clasp has a back plate closing the central cavity on one face of the ring shaped body while the release actuator closes the central cavity on the opposing face, the back plate having an abutment for alignment with a protruding surface of the release actuator to prevent disengagement of the hasp from the snib, the release actuator being biased to a position in which the abutment aligns with the protruding surface.

[001 1 ] Advantageously, the actuator is secured to the back plate in a manner that it can be moved through a predetermined sequence of two movements, the first movement being to slide the protruding surface out of alignment with the abutment on the back plate, and the second movement being a depression of the release actuator towards the back plate to disengage the snib from the hasp.

[0012] In a particularly preferred form, the release actuator is a button biased away from the back plate. By providing the release actuator in the form of a button that is arranged to firstly slide and then to be depressed against a return force to release the buckle, both movements can be performed with the user's thumb pressing on the button exterior. This avoids having to change or adjust the user's grip while opening the buckle so that the buckle can be released quickly and in a manner that is not particularly instructive to a child observing the release action.

[0013] Preferably, the at least one biasing menas comprises two coil springs, one for providing a bias against sliding movement of the release button and the other providing a bias against unhindered depression of the release button.

[0014] In one commercial embodiment, the buckle will have two side strap anchors that releasably attach to opposing sides of the clasp through respective side apertures in the annular (ring-shaped) body, and two shoulder strap anchors which releasably attach two harness straps to an upper side of the clasp. [0015] Preferably, the two side strap anchors are main strap anchors and the two shoulder strap anchors are secondary anchors arranged to releasably engage an associated one of the main strap anchors as well as the annular body of the clasp, the arrangement being such that disengaging the main strap anchors from the clasp simultaneously allows the secondary strap anchors to disengage from the clasp. To this end, in a preferred embodiment, the secondary anchors comprise a through hole in an arcuate beam portion, such that the hasp of the primary anchor is insertable through the side aperture into the clasp and the arcuate beam portion is sandwiched between the primary anchor and the clasp when the buckle is closed. In this way, four separate straps of the harness can be released simultaneously from the buckle with a single operation of the release button.

[0016] Preferably, the main strap anchors and the secondary strap anchors each have a strap threading hole, and the clasp also has a strap threading hole such that the buckle is suitable for a 5 point harness. [0017] Advantageously, the buckle is predominantly made up of eight injection molded polymer components, wherein the release actuator .is comprised of two components. [0018] A preferred embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings.

Brief Description of the Drawings

[0019] Figure 1 is a front perspective of a buckle according to the present invention, with one main strap anchor and one secondary strap anchor detached from the clasp;

[0020] Figure 2 is an enlargement of detail A shown in Figure 1 ;

[0021 ] Figure 3 is an exploded perspective of the clasp and two-part release button of the release actuator of the buckle, with one main strap anchor and one secondary strap anchor detached from the clasp; and

[0022] Figure 4 is an enlargement of detail B shown in Figure 3.

Detailed Description of Preferred Embodiments

[0023] In the following, relative terms such as 'side', 'upper', 'front', 'back' and the like are used to facilitate the skill reader's reading of the description with reference to the drawings.

[0024] Referring first to Figure 1 , the buckle 1 has a clasp 10 which releasbly secures two main strap anchors 20 (of side straps of a harness; not shown) and two secondary strap anchors 50. (of shoulder straps of the harness; not shown). One of the main strap anchors 20 and one of the secondary strap anchors 50 are shown detached from the clasp 10, whilst the other two anchors 20, 50 are shown in the locked / secured position. A release actuator (mechanism) 2 at the clasp enables dislodgment of the anchors 20, 50 from the clasp 10. [0025] The clasp 10 has a generally ring-shaped main body part 1 1 , with two opposing side apertures 12 extending from an outer periphery to an inner central cavity 13 defined by / within the ring-shaped main body part 1 1 . Side apertures 12 are dimensioned to allow passage of and for cooperation with a plate-like hasp 21 of main strap anchors 20. Main body part 1 1 also has two locating receptacles 14 recessed into an upper side of main body part 1 1 , which respectively serve the purpose of receiving and accommodating a locating tongue element 55 of secondary strap anchor 50, as explained below. Finally, as seen in fig. 3, a bottom aperture 16 is provided at main body part 1 1 to loop and secure a not- illustrated crotch harness strap to buckle 1 .

[0026] The secondary strap anchors 50 are generally arcuate injection moulded polymer bodies, having a retention aperture 51 extending through lower limb portion 52, a strap aperture 55 oriented perpendicular to aperture 51 extending through upper limb portion 53 (thus providing a ring loop for a strap) and the above mentioned locating tongue element 55 at a radially inward facing side of upper limb portion 54. The tongue element 55 is grooved at its front end such as to cooperate with guiding ridges 15 protruding inwards from the side walls of locating receptacles 14 at the upper side of ring shaped body part 1 1 , to facilitate correct insertion and locating of the secondary strap anchors 50 at the clasp 10 (see detail Figure 2)..

[0027] The primary strap anchors 20 are unitary polymer moulded bodies, having a strap aperture 22 in rearward portion 23 (thus providing a ring loop for a strap) and the above mentioned plate-like hasp 21 elastically cantilevered from rearward portion 23, with two parallel fingers 24 flanking both sides of hasp 21 to increase overall rigidity and stiffness of primary anchors 20. A central, square window (through-hole) 21 1 is formed near the free end of hasp 21 .

[0028] As may be seen best from figures 1 and 3, retention aperture 51 of secondary anchor 50 is subdivided into three zones, separated by web portions extending across the width of aperture 51 , each zone dimensioned in plan to receive and allow passage of the hasp 21 and the two side fingers 24 such that hasp 21 and fingers 24 may come to rest within the main body part 1 1 of clasp 10. In this way, secondary strap anchors 50 are secured to the clasp 10 when the main strap anchors 20 are inserted and secured to the clasp 10, as is explained below. [0029] Clasp 10 integrates the locking and release actuator 2 of buckle 1 . As may be discerned from Figure 3, release actuator 2 is devised to cooperate with the hasp 21 of primary strap anchors 20 for simultaneously releasing the main strap anchors 20 and the secondary strap anchors 50 which are carried at and retained to the primary anchors 20 without being positively locked to these (other than when the primary anchors 20 are secured to the clasp 10, thereby

sandwiching the secondary anchor's lower limb portion 52 between clasp body part 1 1 and the primary anchor's rearward portion 23).

[0030] The release actuator 2 comprises a button thumb pad 40 that is mounted in slidable manner on a top surface of a button support platform 30 which in turn is dimensioned to be inserted through the front side of and slidably fit for to and fro (up and down) movement within the central cavity 13 of main body part 1 1 of clasp 10. The rear side of central cavity 13 of main body part 1 1 is closed by a bottom plate 60 which is secured to main body portion 1 1 using appropriate fastening means, either permanently or in removable manner. [0031 ] Button support platform 30 is received in central cavity 13 of the clasp 10 to be depressed against the bias of a button depression spring 71 located and acting between bottom plate 60 and the facing rear side of support platform 30. Four barbed support legs 31 integrally formed on the underside of support platform 30 guide and limit the extent of travel which platform 30 can accomplish between the non-depressed and depressed states, the barbed end formations ensuring that platform 30 is retained within central cavity 16 and keep it covered at all times. [0032] As best seen in Figure 4, the underside of button thumb pad 40 has an about centrally located retaining fin 42 ending in retaining flange 43 which extends through a side aperture (not shown) in elongate depression 34 formed in the front face of support platform 30. A button slide spring 72 is located within depression 34 to engage the retaining fin 42 and bias the button thumb pad 40 to the right according to the orientation shown in Figure 3, ie into the button's normal rest position.

[0033] Also extending from the underside of the thumb pad 40 are two posts 41 , located either side of fin 42 (only one post shown). Each post 41 extends through a rectangular slot 33 extending from the front to the rear face of support platform 30 and running parallel to one another. The terminal ends of posts 41 are formed to respectively abut a complementary one of two abutment blocks 61 (only one visible in fig. 3) which are formed integrally on backing (bottom) plate 60 when the thumb pad 40 is biased into its normal rest position. That is, in the actuator button rest position, where the end faces of posts 41 align with and abut the top of complementary abutment blocks 61 , the actuator button 2 is prevented from being depressed into the clasp's cavity 13 and thus from releasing the anchors 20, 50 from the clasp 10.

[0034] In operating the actuator button 2 to unlock the buckle 1 , it is

necessary to first slide the button thumb pad 40 to the left (according to the orientation shown in Figure 3) in order to disengage posts 41 from the

complementary abutment blocks 61 , whereupon the button thumb pad 40 and button support platform 30 can subsequently be jointly depressed into the clasp's cavity 13 against the bias of the button depression spring 71 . This initial slide actuation does not allow removal of the primary anchors 20 from the clasp 10.

[0035] Clasp 10 retains the primary anchors 20 (and the secondary anchors 50 which are carried by the former) firmly secured at the buckle in releasable manner by way of snibs 17 (see fig. 3) which are placed to interact with the hasp through holes 21 1 of the main anchors 20. To this end, snibs 17, which are integrally formed at (or otherwise secured to) the ring shaped main body part 1 1 , protrude downwardly from above and into the side apertures 12 of ring-shaped main body part 1 1 . The snibs 17, small but rigid catch elements, cause the flexible hasps 21 to bent downward in the process of inserting the primary anchor's hasps 21 through the side apertures 12, until the snibs 17 come to pass over the square through holes 21 1 of hasps 21 and the hasps 21 then resiliently flex back into their unbent configuration, whereupon the snibs 17 then locate within the hasp holes 21 1 in locking engagement when the primary anchors 20 are fully inserted into clasp 10 as shown in the bottom part of figure 1 (and 3).

[0036] In order to release the hasps 21 from locking engagement with the snibs 17, the underside of button support platform 30 is provided with integral (or otherwise attached) hasp engagement pedestals 32 which are shaped and located to engage the cantilevered ends of the flexible hasps 21 on each of the main strap anchors 20 during downward movement of the actuator's button (comprised of support plate 30 and slide pad 40). [0037] . The hasps 21 are configured to flex under the contact force of the hasp engagement pedestals 32. As the hasps 21 elastically bend downwards (in accordance with the orientation shown in Figure 3), the snibs 17 disengage from the hasp retention holes 21 1 . With the snibs 17 disengaged from their respective hasps 21 , the main strap anchors 20 simultaneously release from the clasp 10, also releasing the secondary strap anchors 50.

[0038] With the main strap anchors 20 released by the clasp 10, the secondary strap anchors 50 can be readily disengaged from the main strap anchors 20 to allow the child to be more easily removed from the seat. It will be appreciated that in use of the buckle 1 in a 5 point harness, the main strap anchors 20 secure the straps across the lap while the secondary strap anchors 50 secure the shoulder straps. Further, providing separate main and secondary strap anchors that cooperate but are able to disengage from one another freely without operating a separate release mechanism, ensures that the shoulder strap and lap strap on each side of the harness do not form a fixed loop that may catch on a child's arm when lifted out of the seat. [0039] It will be appreciated that by selecting springs 71 , 72 with suitable spring constants, and by selecting the cross-section and other geometry parameters of the hasps 21 of the primary anchors 20, it is possible to adjust the respective forces required to operate the thumb pad 40 and support platform 30, thus providing buckles 1 having different release properties, suited to the application in vehicle child seat harness, five point harnesses for push strollers and likewise applications.

[0040] While the invention has been described with reference to harnesses for children and infants, it is equally applicable to buckles for adult harnesses in which the specific sequence of actuator movements guards against inadvertently releasing the buckle by accidental contact.

[0041 ] Skilled workers in this field will readily understand that the figures depict a single example of a buckle according to the invention. The

complementary formations on the clasp and strap anchors can take a multitude of different forms without departing from the spirit and scope of the broad inventive concept. Similarly the release actuator can be embodied in many different fashions which broadly equate to the button described in the preferred

embodiments.

[0042] Comprises/comprising and grammatical variations thereof when used in this specification are to be taken to specify the presence of stated features, integers, steps or components or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof List of Reference Numbers as used in accompanying drawings

1 buckle

2 release actuator ('buton')

10 clasp

1 1 ring shaped main body part

12 side aperture (x2)

13 central cavity

14 locating receptacle (x2)

15 guiding ridges

16 bottom aperture

17 snibs (at each side aperture 12)

20 main strap anchor (x2)

21 hasp

21 1 hasp through-hole

22 strap aperture

23 rearward portion

24 parallel fingers 30 support platform

31 barbed support legs

32 hasp engagement pedestals

33 rectangular slots

34 rectangular depression

40 thumb pad

41 post (x2)

42 retaining fin

43 retaining flange

50 secondary strap anchor (x2)

51 retention aperture

52 lower limb portion

53 strap aperture

54 upper limb portion

55 tongue element

60 bottom plate

61 abutment blocks

71 button depression spring

72 button slide spring