GB2135728A - Latch mechanism for vehicle sun roof - Google Patents

Abstract

A sun roof latch mechanism comprises a toggle arm 41 connected by a pivot pin 34 to a roof frame 2, the pivot axis extending transversely of an adjacent edge of a hingedly-mounted roof panel 1. A handle 47 is pivotally connected to the arm 41 and to a panel-retaining link 51. The mechanism can be retracted, and the roof panel closed, by lowering the handle with rotation of the arm 41 until the two extend downwards side-by-side. With continued rotation of the arm 41, the arm and the handle can be moved to lie substantially parallel with the panel edge (Figure 9). The link 51 co-operates with the pivot pin 34 to give an over-centre action to maintain the mechanism in its retracted position. Locking means comprising a locking handle 44 and thrust members 42 and 43 enables the mechanism to be locked in substantially any required position of adjustment. <IMAGE>

Description

SPECIFICATION Latch mechanism for vehicle sun roof This invention relates to improvements in vehicle sun roofs and is particularly concerned with latch mechanismsforsuch sun roofs.

According to the invention in one of its aspects a vehicle sun roof comprises a roof panel adapted to be hingedly-mounted in a vehicle and an extensible latch mechanism mounted adjacent to an edge of said panelforreleasablysecuringsaid panel closed, said mechanism comprising a first link which is arranged to be pivotally connected to the vehicle roof for rotation relative thereto about a first pivot axis which extends transversely of said panel edge, and a second Iinkwhich is pivotally connected to said first linkfor rotation relative thereto about a second pivot axis and is pivotally connected to said roof panel for rotation relative thereto about a third pivot axis, the arrangement being such that in a fully open position of said roof panel with said mechanism fully extended said first and second links extend successively upwards from said first pivot axis towards said roof panel and in closing said panel said second linkiswith rotation of said first link moved downwards to a position in which it lies substantially alongside said first link extending downwards from said first pivot axis, the arrangement furthermore being such that said first and second links can thereafter be moved with continued rotation of said first link until a retracted condition of said latch mechanism is achieved in which they extend in generally the same direction as the panel edge.

By means of such an arrangement a sidewaysoperating latch mechanism can be provided which is simple in its essential construction and very slim when retracted.

Preferablythe arrangement is such that the second pivot axis passes between the first and third pivot axes in adjusting the mechanism to itsfullyextended condition in an over-centre action whereby the roof panel can maintained in its fully open position; the weight of the roof panel then acts to prevent retraction of the mechanism.

The latch mechanism may comprise also a third link wherebythe second link is pivotally connected to the roof panel,the third link being pivotally connected to the second link for rotation relative thereto about the third pivot axis.

To maintain the roof panel closed (i.e. the latch mechanism in its retracted condition) the mechanism may be so arranged thatthe first pivot axis passes between the second and third pivot axes in an over-centre action in adjusting the mechanism to its retracted condition. In a preferred construction, in which the latch mechanism comprises also a third link as hereinbefore referred to, the first link is mounted for rotation about the first pivot axis on a pivot pin and the third link is provided with a recess arranged to receive the pivot pin, so to provide forthe over-centre action as the mechanism is adjusted to its retracted condition.

Most preferably the latch mechanism comprises locking means whereby it can be locked in at least one intermediate condition between the fully open and closed positions of the roof panel. In one preferred arrangement the locking means comprises a locking handle pivotally mounted on the second linkfor rotation relative thereto about the second pivot axis, the locking handle being movable between a release position and a locking position in which relative rotational movement between the first and second links is prevented.To achieve this the locking means can comprise at least one pair of axially opposed thrust members arranged for relative rotation about the second pivot axis, one of the thrust members being non-rotatably mounted on the locking handle and the otherthrust member being non-rotatably mounted on the second link, the arrangement being such that axial movement of separation occurs between the thrust members upon moving the locking handle from its release position to its locking position, such movement of separation resulting in said other ofthe thrust members preventing relative rotational movement between the first and second links.Relative rotational movement can be prevented by means of interengaging formations of axially opposed faces ofthethrust member and the first link; preferably at least one ofthe opposed faces comprises a plurality of engageableformations enabling the latch mechanism to be locked in any of a plurality of intermediate positions. Most preferably, to achieve a balance locking load on the link, the locking means comprises two pairs of axially opposed thrust members arranged to act upon the first linkfrom opposite sides.

According to the invention in another of its aspects a vehicle sun roof comprises a frame adapted to be fitted in the roof of a vehicle, a roof panel, and at least one hinge assembly hingedly mounting the panel on the frame, the frame consisting oftwo sections adapted to grip between them a vehicle roof around the edges of an aperture formed therein, the upper of said sections having an arcuate surface on its lower face and a beading of resilient material applied to its upperface, and the or each hinge assembly being provided with an arcuate leaf member which is detachably engageable with said arcuate surface of the upperframe section, wherein a latch mechanism is secured to the frame at its side remote from the or each hinge assembly and comprises a handle pivotal ly connected atone end to the roof panel, a link member pivotally connected at one end to the other end ofthe handle and a latch bracket pivotally connected to the other end of the link member, said latch bracket comprising an arcuate blade adapted to be held in engagement with the arcuate surface ofthe upper frame section to secure the latch mechanism to said frame.

The arcuate blade of the latch mechanism desirably corresponds in shape to the arcuate leaf member of the or each hinge assembly. Further, the arcuate blade of the latch mechanism is preferably removably held in the frame whereby it can be withdrawn from said frame to permitthe panel to be removed from the vehicle roof.

An embodiment ofthe invention will now be described, by way of example, with reference to the drawings, in which: Figure lisa plan view of a vehicle sun roof with part of a roof panel cut away to show the construction of a frame ofthe sun roof; Figure2is a section taken on the line ll-ll in Figure 1 in the direction ofthe arrows showing the roof panel in a fully open position, and showing a latch mechanism and a hinge assembly with certain components exploded forthe sake of clarity; Figure3isa diagrammatic section of the latch mechanism taken in the direction of the arrow III in Figure 2 and showing the relative positions of various componentsofthe latch mechanism in afully extended condition in the fully open position of the roof panel;; Figure 4 is a section, corresponding to Figure 3, showing the relative positions ofthe components of the latch mechanism afterthe roof panel has been moved to a closed position but before the latch mechanism has been moved to a retracted condition; Figures5to9are sections, corresponding to Figures 3 and 4, showing the operating sequence in moving the latch mechanism to its retracted condition; Figure 10is a side elevation of a toggle arm ofthe latch mechanism; Figure 11 is a side elevation of a th rust washer of the latch mechanism; Figure 12 is a section taken on the line XII-XII in Figure 11 in the direction ofthearrows; Figure 13 is a side elevation of a lock handle of the latch mechanism; Figure 14 is a side elevation of a flanged sleeve of the latch mechanism;; Figure 15is a section taken on the line XV-XV in Figure 1 4 in the direction of the arrows; Figure 16 is a side elevation of a catch of the latch mechanism; Figure 17 is an exploded perspective view showing particularly components of locking means ofthe latch mechanism; Figure 18is a plan view of a guide member of the latch mechanism; Figure 19is a side elevation of the guide member shown in Figure 18; Figure 20 is a section taken on the line XX-XX in Figure 18; and Figure 21 is an exploded perspective view showing componentswherebythe latch mechanism is releasably secured to the sun roof frame.

Referring to the drawings, the vehicle sun roof according to the invention comprises a roof panel 1 which is hingedly mounted on a frame 2. As shown more particularly in Figures 2 and 21, the frame consists of an upper section 3 which is adaped to fit into and to overlap the edges of an aperture formed in a vehicle roof (not shown) and a lower section 4 adapted to engage with the upper section 3 and the underside ofthe vehicle roof. The upper section is provided with a shallow channel to receive a seal 5 of resilient material and the vehicle roof is pressed againstthe seal 5 by an arm 6 of the lower section 4 of the frame. The lower section 4 is secured to the upper section 3 by a series of clamp screws the head 7 of one of which is shown in Figure 2.The two frame sections pivot against one another, underthe action ofthe clamp screws, to create a positive clamping action on the vehicle roof. Aftertheframe 2 has been fitted to the vehicle roof, the roof headlining (not shown) is drawn overthe lowersection 4 and is fixed thereto by wrapping the edge of the headlining around the inner edge of the section 4 and by pressing a trim strip (not shown) of resilient material between the upper section 3 and the lower section 4to hold the headlining in position. This is entirely conventional and will be clear to those skilled in the art. The underside ofthe fitted frame is completely hidden from view and the only visible parts are the hinge assemblies and latch mechanism.

Any suitable hinge assembly may be used but it is preferred to usethe hingeassemblywhich forms the subject of British PatentApplication NG. 8305468.

In the embodiment shown in the drawings, a pairof hinge assemblies are secured tothe roof panel 1 by respective fixing caps 9 (only one cap 9shown in Figure 1).

A beading 11 of resilient material which servesas a seal forthe panel 1 when said panel is units closed position is fitted to the upperframesection 3. Forthis purpose, the upperframe section 3 is provided on its uppersurfacewitha pairofchannelsl2and 13 disposed respectively in faces 14 and 15 of the section which extend at right angles to one another. The beading has a pair of ribs 16 and 17 which are receivable, respectively, in the channels 12 and 13 wherebythe beading is securely held in the upper frame section.

The lower surface of the frame section 3 is provided with an arcuate portion 18which serves as a guide surfacefor an arcuate leaf member 25 of a hinge assembly. In the embodiment shown in the drawings, a guide member 21 having an arcuate surface 22 which faces the arcuate surface 18 to form therewith an arcuate channel is positioned between the upper frame section 3 and the lowerframe section 4. The guide member 21 is provided with a groove for engagement with a rib 20 on the lower frame section 4 and with a recess 24 one face of which is adapted to engage a ribbed edge 19 ofthe lower frame section 4 wherebythe guide member21 is securely held in placeagainstthelowerframesection4asshown in Figure 2.Aguide member 21 is provided for each of the hinge assemblies sothat, inthe case ofthe embodiment shown in the drawings, two guide members are provided although onlyone is shown.

The trimming ofthe roof headlining is completed in the area ofthe hinge guides by tucking itintothesmalt gap between the ribbed edge 19 of the lowerframe member4 and the recess 24 in the guide member21 where it is retained by a length of resilient material 39 pressed in afterthe headlining which is not shown.

Said length of material is initially round in crosssection and the gap is narrower atits entry than inside so that it acts as a clawtocompletetheretention.

Each hinge assembly consists of an arcuate leaf member 25 which is securedto the roof panel 1 by means of a respectivefixing cap 9. Reference can be made to Patent Application No.8305468 for a more detailed description oftheconstruction and operation of the hinge assembly.

The panel 1 can be secured in the closed position shown in Figure1 orretainedintheopen position shown in Figure 2 by means of a single extensible latch mechanism located adjacenttothe rearedgeof the panel. The latch mechanism comprises an arcuate latch bracket 31 (Figure 2) which is held against the arcuate surface 18 of the upper frame section 3 by virtueofthe resilience of the beading 11 via a handle assembly. The latch bracket 31 is provided with a pair of depending lugs 32 (see also Figure 17)which are bored to receive a hinge pin 33. Pivotally mounted on the hinge pin 33 is the head of a pivot pin 34.The shank of said pivot pin is provided, intermediate its ends, with a flange 35 and pivotally mounted on said shank for rotation about a first pivot axis is a first link in the form of a toggle arm 41. The toggle arm is held against the flange 35 by means of a circlip or blind rivet 38 provided atthe end ofthe shank of the pivot pin 34. As is apparent from Figures 2 and 3, the first pivot axis extends transversely of the rear edge ofthe panel 1.

The toggle arm 41 is pivotally connected to a second link in the form of a primary handle 47, for rotation relative thereto about a second pivot axis, by a pin or bolt46.Also mounted on the pin orbolt46arefirst thrust members in the form of two flanged sleeves 42 on which a lock handle 44 is rigidly mounted and the primary handle 47 is pivotally mounted. The flanged ends of the sleeves are spaced from thetogglearm 41 by second thrust members in the form oftwo thrust washers 43. The bolt46 is secured in position by means of a nut 45.Locking means of the latch mechanism, comprising the lock handle 44, the sleeves 42 and the thrust washers 43, enables the mechanism to be locked in a plurality of intermediate conditions as well as in thefully extended and retracted conditions.

The panel 1 is provided, adjacent to its rear edge, with a bore 55 in which a fixing cap 56 is located. The fixing cap is provided with a tubular portion which houses a ball cup 57 retained in the fixing cap by a circlip 58. The fixing cap 56 is held in position in the bore 55 in the panel 1 by a retaining ring 59 which fits overthetubular portion ofthefixing cap on the underside ofthe panel 1 and is retained by a spring fastener 61.An O-ring 62 is provided in a groove in the retaining ring 59 and a sealing washer 63 of resilient material is provided under a flanged head portion of the fixing cap 56.The O-ring 62 and washer 63 seat against the respective surfaces ofthe panel 1 and ensurethatthe fixing cap 56 can be securely held in the bore 55 in the panel 1 without risk of damage to the panel and, atthe sametime, preventthe ingress of waterfrom the outside upper surface ofthe panel.

A link51, providing a third link of the latch mechanism, is mounted intheball cup 57,the link having a partially spherical surface 52 for engagement with a corresponding surface of the bail cup to allow for universal movement ofthe link. An under crown surface ofthe cap 56 is provided with a cylindrical projection 53 adapted to receive an O-ring 54 of resilient material and the other end ofthe link 51 is pivotally connected to the primary handle 47 by a pivot pin or bolt49 for rotation relative to the handle 47 about a third pivot axis ofthe mechanism. By means of the pivot pin 49 the primary handle 47 is thus indirectly pivotally connected to the roof panel 1.

In the open position of the panel 1 as shown in Figures 2 and 3 of the drawings, with the lock handle 44 in a locking position aligned with primary handle 47,the primary handle extends substantially parallel to the toggle arm 41 as shown in Figure 3. The toggle arm 41,the primary handle 47 and the link 51 extend successively upwards to the roof panel 1. The panel 1 can be moved to the closed position by moving the lock handle 44 in an anti-clockwise direction to a release position as viewed in Figure 3 and pulling down on the handle. This has the effect of causing the toggle arm 41 to rotate about the pivot pin 34 (in a clockwise direction as viewed in Figure 3) and the primary handle 47 to be moved downwards until an ear 48 of the link 51 bears against the pivot pin 34.The handle 47 then lies substantially alongside the toggle arm 41 extending downwardsfrom the pivotpin 34 (and so the vehicle roof), the position being illustrated by Figures 4 and 5. Itwill be seen thatthe primary handle 47 is no longer substantially parallel to the toggle arm 41 and the lock handle 44 extends substantially perpendicular to the primary handle 47.

The primary handle 47 must now be moved with continued rotation ofthetoggle arm 41 (i.e. in a clockwise direction as viewed in Figure 4) which will causethe ear 48 to move around the pivot pin 34 and will also cause the edges ofthe panel to engage with the resilient beading 11. This position is indicated diagrammatically in Figure 5. Continued movement of the primary handle 47 will cause the tip ofthe ear 48 to pass overthe shank of the pivot pin 34 so that said pin begins two enter a recess 50 in the link as indicated in Figure 6. The beading 11 now undergoes initial compression as the panel 1 is drawn downwards by the latch mechanism.

Further movement of the primary handle 47 causes the pivot pin 34to be fully received in the recess 50 in the link 51 to achieve full compression of the beading 11 as indicated in Figure 7. The latch mechanism is still however not in its fully retracted condition and projects downwardly from the frame. The pivot axes ofthe pin 46, pivot pin 34 and pivot pin 49 are however aboutto enter a toggle situation giving rise to an over-centre action. If the primary handle 47 is now moved still further, the axis of the pivot pin 34 will pass between the axes of the pins 46 and 49 and the primary handle 47 will be moved to a position in which it almost touches the underside ofthe panel 1.This position is indicated in Figure 8 and the position of the primary handle is defined by contact with the toggle arm 41 at the end which is mounted on the pivot pin 34. The primary handle 47 will therefore be retained in the position indicated in Figure 8 in which it and the toggle arm 41 extend substantially parallel to the frame and rear edge of the panel, upwards movement of the handle being prevented by its engagement with thetoggle arm 41 and the handle being restrained from downwards movement by the over-centre action ofthetoggle linkage.

The only component now projecting to any appreciable extent below the frame is the lock handle 44 and this handle can now be pivoted to the locking position shown in Figure 9 in which it is again aligned with the primary handle 47 in orderto provide additional securityforthe primary handle in its fully retracted position as well as to improve the aesthetic appearance of the latch mechanism.

The panel 1 can be opened in the reverse sequence and it will be seen thatthe panel 1 is retained in the open position shown in Figure3 by the over-centre action ofthe pivot pins 34,46 and 49, as well as by the lock mechanism, the second pivot axis (at the pin 46) having passed between the first and third pivot axes (atthe pins 34 and 49, respectively) in adjusting the mechanism to its fully extended condition, In itsfully extended condition the toggle arm 41 bears against a depending portion ofthe handle 47 below the pivot pin 46 to prevent further anti-clockwise rotation ofthe toggle arm 41.

The panel 1 can be held open in a number of intermediate positions by means of the locking means. The toggle arm 41 is provided with a plurality of radially extending ridges 64 which are interengageable with similar radially extending ridges 65 provided on thethrustwashers 43 as indicated in Figures 10, 11 and 17 of the drawings.The thrustwashers are non-rotatably mounted against the handle 47. The nut PE on the pin or bolt 46 is adjusted so that the interengagementofthe ridges 64 and 65 will hold the panel 1 in any position to which the latch mechanism is moved when the lock handle 44 is in the locking position.When the lock handle 44 is moved to the release position, the clamp load between the ridges 64 and 65 is reduced and they can be moved over one anotherto move the panel 1 either to a further open or closed position.

As illustrated in Figure 13, the lock handle 44 is provided with a pair of recesses 67 which are adapted to receive correspondingly shaped projections 68 provided on the two sleeves 42 (Figure 14). As shown in Figure 15, the otherflange surface of each sleeve 42 is provided with a cam surface 69 which is arranged to engage with a similar cam surface 66 provided on the axially opposed thrust washer 43 (Figure 12). When the lock handle 44 is moved from its release position to its locking position, shown in Figures 3 and 9 ofthe drawings, it is effective to move the cam surfaces 69 on the sleeves42 (by rotation ofthe sleeves) into engagementwith the cam surfaces 66 on thethrust washers 43, whereby each pair of thrust washers and sleeves is forced apart, and the two thrust washers are forced towards one another to grip the toggle arm 41.

The ridges 64 and 65 are thus forced into firmer interengagement and the toggle arm is prevented from pivoting aboutthe bolt46 relative to the primary handle 47. The panel 1 can thus be effectively locked in position.

On the other hand, ifthe lock handle 44 is moved to the release position, shown in Figures 4to 8 ofthe drawings, it is effective to move the cam surfaces 69 on the sleeves 42 to a position in which the raised surfaces engage in dwells in the cam surfaces 66 on theth rustwashers 43. The force exerted by these washers on the toggle arm 41 is thus relieved and the ridges 64 and 65 can move over one anotherto permit pivoting of the toggle arm 41 aboutthe primary handle 47 and, hence, movement ofthe panel 1. Returning the lock handle 44to the locking position shown in Figures 3 and 9 ofthe drawings will again lockthetoggle arm 41 againstfurthermovement.

As stated above, the arcuate latch bracket 31 is maintained againstthe arcuate surface 18 ofthe upper frame section 3 by virtue of the resilience ofthe beading 11. Additionally, the latch bracket is provided with a bore in which a catch 71 (Figures 16 and 21) is engageable in orderto restrain the latch bracket from rotating about its pivot centre on the frame. The catch 71 is provided on a plate 72 which carries at each end a tubular projection 73. Each projection 73 contains a coil spring 74 (shown diagrammatically as exploded in Figures 2 and 21) and a groove extends along the plate 72 from one end to the other between the projections 73.

If desired (and as shown in Figure 21) the groove may be replaced between each projection 73 and the central catch 71 by a pair of slots extending right through the plate. The groove and slots serve to receive a wire form 76 having looped ends which are secured by rivets 77 to the upperframe section 3 in the channel 13. These components are shown as ex plodedin Figures2and21.Thecatch71 and projections 73 pass th rough bores 91 and 92, respectively, in the upperframe section 3 so as to extend from the arcuate surface 1 8with the projections 73 being located on either side ofthe arcuate latch bracket 31.The catch 71 is thus urged into a bore 30 in said latch bracket 31 by the springs 74 reacting against the wire form 76.

The tubular projections 73 also extend through bores 93 in the lowerframe section 4 and are each provided with a bore 78 (Figure 16) of hexagonal cross-section for the reception of associated nuts 79 by means of which a release pad in theform of a plate 82 can be secured, with the aid of screws 81, below the lower frame section 4. The plate 82 is spaced from the lower surface ofthe frame section 4 by the projections 73 as shown in Figure 2. Atrim frame 83 surroundsthe plate 82 and is securedtothe lowerframe section 4 by screws 84 in orderto guide the plate 82. The springs 74 and wire form 76 are thus stressed and are effective to hold the catch 71 positively in engagement in the bore in the arucate latch bracket 31.

If it is desired to remove the panel 1 from the frame 2, the panel 1 mustfirst be moved to an open position such as the one shown in Figure 2 ofthe drawings. The plate 82 mustthen be depressed. This has the effect of forcing the plate 72 upwards (as viewed in Figure 2) by virtue ofthe projections 73 and the catch 71 is thus forced out ofthe bore in the arcuate latch bracket 31 againsttheforce of the springs 74. The latch bracket 31 can then simply be withdrawn from the frame 2. The arcuate leaf members 25 of the hinge assemblies can then be withdrawn from the oppositeside oftheframe in like manner in orderto detach the panel from the frame.

When it is desired to re-fit the panel, the arcuate leaf members 25 ofthe hinge assemblies are first reinserted into the frame 2 after which the panel 1 is lowered until the arcuate latch bracket31 is opposite the frame 2. A guide memmber85 (Figures 2,18 and 21) is provided in this region said guide member having a arcuate surface 94which faces the arcuate surface 18 ofthe upper frame section 3 to form therewith an arcuate channel. The guide member85 is provided with cut-outs 89 for engagement with the rib 20 on the lowerframe section 4 and with a recess one faceofwhich isadaptedtoengagethe ribbed edge 19 ofthe lowerframe section 4.The guide member85 is provided with afirst pairof bores 86 (Figure 18) and the rivets 77 pass through these bores to secure the guide memberto the upper frame section 3. A second pair of bores 87 are also provided in the guide member 85 and further rivets 96 pass th rough these bores and also serve to secure the guide member to the frame section 3. The lower frame section 4 is secured to the guide member 85 by the screws 84 which screw into further bores 88 in said guide member. The edges of the guide member85, provided with the cut-outs 89, are adapted to fit over the rib 20 on the lower frame section 4, the rib being partly machined away in the region occupied by the body of the guide member.

The end regions of the guide member are provided with raised portions 90 for guiding the arcuate latch bracket 31 into the arcuate channel defined between the arcuate surface 18 and the guide member 85.

The catch 71 is provided with a tapered surface 70 which is engaged by the leading edge of the latch bracket 31 as said bracket is guided into the arcuate channel. The catch 71 is thus pressed upwards against the force ofthe springs 74 and the latch bracket moves underthe catch until the bore therein passes underthe catch when the springs 74 are effective to force the catch 71 into said bore to secure the latch bracket in position.

Although only one latch mechanism has been shown in the drawings it is possible to provide two or even more latch mechanisms for greater security if desired.

The resilient beading 11 may, if desired, be provided on its uppersurfacewith one or more ribs 10to provide an effective seal for the panel 1 when said panel is in its closed position.

The panel 1 is preferably made oftransparent or translucent material butthis is not essential and the panel may, if desired, be made of opaque material.

Claims (13)

1. Avehicle sun roof comprising a roof panel adapted to be hingedly-mounted in a vehicle and an extensible latch mechanism mounted adjacent to an edge of said panel for releasablysecuring said panel closed, said mechanism comprising a first linkwhich is arranged to be pivotally connected to the vehicle roof for rotation relative thereto about a first pivot axis which extends transversely of said panel edge, and a second link which is pivotally connected to said first linkfor rotation relative thereto about a second pivot axis and is pivotally connected to said roof panel for rotation relative thereto about a third pivot axis, the arrangement being such that in a fully open position of said roof panel with said mechanism fully extended said first and second links extend successively upwards from said first pivot axis towards said roof panel and in closing said panel said second link is with rotation of said first link moved downwards to a position in which it lies substantially alongside said first link extending downwards from said first pivot axis, the arrangementfurthermore being such that said first and second links can thereafter be moved with continued rotation of said first link until a retracted condition of said latch mechanism is achieved in which they extend in generally the same direction as the panel edge.

2. A vehicle sun roof according to claim 1 wherein the arrangement of said latch mechanism is such that said second pivot axis passes between said first and third pivot axes in adjusting said mechanism to its fully extended condition in an over-centre action whereby said roof panel can be maintained in its fully open position.

3. Avehicle sun roof according to eitherof claims 1 and 2 wherein said latch mechanism comprises also a third linkwherebysaid second link is pivotally connected to said roof panel, said third link being pivotally connected to said second linkfor rotation relative thereto about said third pivot axis.

4. Avehicle sun roof according to eitherof claims 1 and 2 wherein the arrangement of said latch mechanism is such that said first pivot axis passes between said second and third pivot axes in adjusting said mechanism to its retracted condition in an over-centre action whereby said roof panel can be maintained closed.

5. Avehicle sun roof according to claim 4wherein said latch mechanism comprises also a third link whereby said second link is pivotally connected to said roof panel, said third link being pivotally connected to said second linkfor rotation relative thereto about said third pivot axis, said first link being mounted for rotation aboutsaid first pivot axis on a pivot pin and said third link being provided with a recess arranged to receive said pivot pin to provide for said over-centre action as said mechanism is adjusted to its retracted condition.

6. Avehicle sun roof according to any one of claims 1 to 5 in which said latch mechanism comprises locking means whereby it can be locked in at least one intermediate condition between the fullyopen and closed positions of said roof panel.

7. Avehicle sun roof according to claim 6 wherein said locking means comprises a locking handle pivotally mounted on said second linkfor rotation relative thereto about said second pivot axis, said locking handle being movable between a release position and a locking position in which relative rotational movement between said first and second links is prevented.

8. Avehiclesun roof according to claim 7 wherein said locking means comprises at least one pair of axially opposed thrust members arranged for relative rotation about said second pivot axis, one of said thrust members being non-rotatably mounted on said locking handle and the other of said thrust members being non-rotatably mounted on said second link, the arrangement being such that axial movement of separation occurs between said thrust members upon moving said locking handle from its release position to its locking position, such movement of separation resulting in said other of said thrust members preventing relative rotational movement between said first and second links.

9. Avehiclesun roof according to claim 8wherein relative rotational movement between said first and second links is prevented by means of interengaging formations of axially opposed faces of said other thrustmemberand said first link.

10. Avehicle sun roof according to claim 9 wherein at least one of said opposed faces comprises a plurality of engageable formations enabling said latch mechanism to be locked in any of a plurality of intermediate positions.

11. A vehicle sun roof according to any one of claims 8,9 and 10 wherein said locking means comprises two pairs of axially opposed thrust members arranged to act upon said first linkfrom opposite sides.

12. Avehicle sun roof comprising a latch mechanism constructed arranged and adapted to operate substantially as herein before described with referpence to the accompanying drawings.

13. Avehicle sun roof comprising a frame adapted to be fitted in the roof of a vehicle, a roof panel, and at least one hinge assembly hingedly mounting the panel on the frame, the frame consisting of two sections adapted to grip between them a vehicle roof around the edges of an apertureformed therein, the upper of said sections having an arcuate surface on its lowerface and a beading of resilient material applied ,o its upperface, andtheoreach hinge assembly being provided with an arcuate leaf member which is detachably engageable with said arcuate surface of the upperframe section, wherein a latch mechanism is secured to the frame at its side remote from the or each hinge assembly and comprises a handle pivotally connected at one end to the roof panel, a link member pivotally connected at one end to the other end ofthe handle and a latch bracket pivotally connected to the other end of the link member, said latch bracket comprising an arcuate blade adapted to be held in engagement with the arcuate surface of the upperframe section to secure the latch mechanism to said frame.