SLIDING ROOF FOR MOTOR VEHICLES

Abstract: A sliding roof for a motor vehicle has a rigid panel (20) closing an opening in the vehicle roof and which can be opened either by sliding the panel rearwardly below the vehicle roof (14) behind the opening or by pivoting the panel upwardly about a transverse horizontal axis adjacent to its front edge so that the rear edge of the panel is above the vehicle roof (14). The rear edge of the panel (20) is supported on a sliding shoe (56) which is connected to the panel (20) by a chain of three links (44, 48 and 52). Each of the connections (42, 46, 50 and 54) at the ends of the chain and between adjacent links thereof is arranged to permit relative angular movement over a limited range between an orientation such that adjacent links are in line with each other and parallel to the shoe (56) and an orientation such that adjacent links are at obtuse angles to each other and project upwardly.

Description: "Sliding Roof for Motor Vehicles" This invention relates to a sliding roof for a motor vehicle of the type having a rigid panel closing an opening in the vehicle roof and which can be opened either by sliding the panel rearwardly below the vehicle roof behind the opening or by pivoting the panel upwardly about a transverse horizontal axis adjacent to its front edge so that the rear edge of the panel is above the vehicle roof. A sliding roof of this kind is disclosed in Patent Specification GB-A-1523538 but the mechanism disclosed involves a complex arrangement of slide guides and cam followers. The present invention is concerned with the provision of a simple mechanism for an opening roof of this type. According to the invention, a sliding roof assembly for a motor vehicle comprises a rigid roof panel which is supported at each side by front and rear guide means on respective guide tracks extending along each side of an opening in the vehicle roof and behind said opening below the vehicle roof, together with means for moving the rear guide means along the guide tracks, the front guide means being adapted to permit pivotal movement of the panel about a horizontal axis at right-angles to the guide tracks and each rear guide means comprising a guide shoe slidably received in the corresponding guide track and connected to the roof panel by a chain of at least two links, each of the connections at the ends of the chain and between adjacent links thereof being arranged to permit relative angular movement over a limited range between an orientation such that adjacent links are in line with each other and parallel to the guide rail and an orientation such that adjacent links are at obtuse angles to each other and project above the guide rail. Preferably the length of the link connected to the roof panel is chosen so that, when said link has pivoted to said obtuse angle relative to the next adjacent link which has remained parallel to the guide rail, the rear edge of the roof panel is level with the adjacent vehicle roof. In one form of the invention, the chain links have formations adapted to engage with the guide track so as to inhibit movement thereof out of line with one another when any part of the roof panel is under the vehicle roof behind the opening. The front guide shoes may include formations adapted to engage with complementary formations on the track so as to inhibit a rearward movement of the front guide means except when the rigid roof panel is at the angle to the guide rails which it adopts when all the chain links are in line with one another. Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a fragmentary perspective sectional view of a motor car fitted with a sliding roof assembly of the type to which the invention relates, showing the roof panel in its closed position and each of its two alternative open positions; Figure 2 is a cross-sectional view of a guide rail extending along the side of the roof opening; Figure 3 is a fragmentary longitudinal sectional view through one of the guide tracks of the roof illustrated in Figure 1, showing the rear edge of the roof in closed position; Figure 4 is a fragmentary cross-sectional view, taken in the same plane as that shown in Figure 1 but showing the front edge of the panel; ; Figure 5 is a fragmentary cross-sectional view, corresponding to Figure 3 but showing the rear edge of the roof after partial sliding rearwardly below the vehicle roof; Figure 6 is a fragmentary cross-sectional view, corresponding to Figure 4 but showing the roof after its rear edge has been lowered prior to sliding rearwardly below the vehicle roof; Figures 7 and 8 are fragmentary cross-sectional views, corresponding to Figures 3 and 4 but showing the roof panel in its upwardly pivoted position; Figure 9 is a perspective view of part of the drive mechanism for the roof shown in Figure 3; and Figures 10 and 11 are perspective views of alternative forms of drive mechanims to that illustrated in Figure 9. Figure 1 shows the upper part of the body of a saloon motor car comprising a bonnet 10, a windscreen 12, a roof 14, a rear window 16 and a boot 18. A moveable glass roof panel 20 is located in a frame 22 bounding an opening in the vehicle roof 14 and including a drain tray 24 forming the bottom of a chamber into which the roof panel 20 can be slid below the vehicle roof 14. A respective guide track, on which the panel 20 is slideable, extends along each side of the opening in the vehicle roof 14 and into the space above the drain tray 24. Figure 2 shows the track 26 on the car driver's right-hand side of the opening in the vehicle roof 14, in transverse cross-section. The track 26 consists of a generally U-shaped channel with the tops of the side limbs turned inwardly to form shoulders 28 and 30, and with a groove 32 of almost completely circular crosssection in the bottom. On the side facing inwardly towards the roof opening, the guide channel 26 includes a laterally facing slot 34 for accommodating a sun-blind (not shown) which can slide below the glass panel 20. Turning now to Figure 3, the panel 20 is supported at its right-hand rear corner by a bracket 40 secured to its undersurface. The bracket 40 is pivotally connected, by a pivot pin 42 to a link 44 which, in turn is pivotally connected by a pin 46 to a second link 48. The second link 48 is pivotally connected by a pin 50 to a third link 52 which is pivotally connected by a pin 54 to a slider 56. The various links 44, 48 and 52 and the slider 56 are of inverted T-shaped cross-section, having the cross-bar engaging in the channel under the shoulders 28 and 30 with the stem projecting upwardly therebetween. As can be seen, the pivot joints between the links 44, 48 and 52 and the slider 56 are constructed to permit angular movement 0 upwardly from the horizontal over a range of about 45 . As can -best be seen from Figure 5, the shoulder 28 is cut-away over a zone 58 just in front of the rear edge 60 of the opening in the vehicle roof 14, and the shoulder 30 is similarly cut-away, to allow the cross-bars of the T-shapes of the links 44, 48 and 52 to move upwardly through this zone out of engagement with the bottom of the track 26. The slider 56 is coupled to a drive cable (not shown) which is accommodated in the groove 32 and which can be used to propel the slider 56 along the track 26. Figure 4 shows the front end of the track 26 and the front edge 62 of the opening in the vehicle roof 14. The shoulders 28 and 30 are cutaway so as to permit the track 26 to accommodate a ramp insert 64, the top surface of which has a sloping portion 66 extending upwardly from the bottom of the track 26 and leading into a horizontal portion 68 having a cylindrical recess 70 at its front end. The front wall of the recess 70 is extended upwardly above the level of the horizontal surface 68 to provide an abutment 72. A bracket 74 is secured to the underside of the panel 20 adjacent to the front right-hand corner thereof. The bracket 74 is of substantially the same width as the -stems of the T-shapes of the links 44, 48 and 52, i.e. less than the width between the shoulders 28 and 30 on the track 26, and has a forwardly projecting portion 76 spaced from the undersurface of the panel 20 and carrying, on its front end, a transverse cylindrical formation 78, the same width as the cross-bars of the T-shapes of the links 47, 48 and 52. A shoulder 80 extends from the front end of the shoulder 28 parallel to the ramp 66 and terminates just before the recess 70. A similar shoulder (not shown) extends from the front end of the shoulder 30 on the other side of the track. A spring member 82 secured to the front edge of the ramp member 64 extends backwardly between the ends of the shoulder 80 and the corresponding shoulder leading from the shoulder 30 of the track 26. Corresponding mechanisms to those shown in Figures 3 and 4 are provided for supporting the left-hand side of the panel 20. When the panel 20 is in the closed position level with the vehicle roof 14, the first link 44 is inclined at its maximum angle to the adjacent link 48 which is in line with the link 52 and the slider 56. At the front end of the roof, the bracket 74 is located with its cylindrical formation 78 in contact with the abutment 72 but held clear of the bottom of the recess by a cam surface 84 formed by the bottom edge of the bracket 74, so as to abut against the top of the sloping portion 66 of the ramp member 64. In this position, a shoulder 86 formed on the cylindrical formation 78, engages with the edge of the hemispherical recess 70 so as to prevent backward movement of the panel 20 into contact with the rear edge 60 of the opening in the vehicle roof 14. The assembly is held in this position by the drive cables which prevent backward movement of the slider 56 and the corresponding slider on the other side of the roof. When the panel 20 is to be slid into the void between the vehicle roof 14 and the drain tray 24, the slider 56 is moved backwards to the position shown in Figure 5. Initially, engagement of the abutment 86 with the rear edge of the cylindrical recess 70 prevents backward movement of the panel 20, with the result that the first link 44 pivots downwards into abutment with the bottom of the track 26. The resulting downward movement of the rear edge of the panel 20 causes pivotal movement on the cam surface 84 (Figure 4), with the result that the abutment 86 is lifted out of engagement with the rear edge of the cylindrical recess 70, flexing the spring 82. The rear edge of the panel 20 is now below the rear edge 60 of the opening in the vehicle roof 14. Continued backward movement of the slider 56 causes the panel 20 to slide backwards, the cylindrical portion 78 of the bracket 74 coming into engagement with the horizontal part 68 of the ramp insert 64 as the cam surface 84 disengages from the sloping part 66 thereof. The cylindrical portion 78 is guided into the track by the shoulder 80 and the corresponding shoulder on the other side thereof. The first link 44 has by now moved clear of the cut-away zone 58 and under the shoulders 28 and 30 of the track so that upward movement of the rear edge of the panel 20 is prevented. The panel 20 can then be slid rearwardly to the maximum extent to the position, illustrated in chain-dotted lines in Figure 1, between the vehicle roof 14 and the drain tray 24. When the roof is to be closed again, the slider 56 is moved forward by the drive cables, the cylindrical portion 78 sliding up the ramp 64 under the upturned end of the spring 82 and into engagement with the abutment 72. Continued forward movement of the slider 56 causes the first link 44 to pivot upwardly through the cut-away zone 58 to return the panel 20 to its position level with the vehicle roof 14, as shown in Figures 3 and 4. If the slider 56 is moved further forwards by the drive cables, the link 48 starts pivoting about the pin 50, forward movement of the panel 20 being prevented by the engagement of the cylindrical portion 78 of the bracket 74 with the abutment 72 at the front of the panel. The cylindrical member 78 moves to the bottom of the recess 70 and subsequent upward pivotal movement of the panel 20 takes place about this recess, the cam surface 84 separating from the ramp 64. At the rear of the panel 20, pivotal movement of the link 48 about the pin 50 continues as the slider 56 moves forwards until the maximum permitted pivotal movement has taken place. The next link 52 is now aligned with the cut-away zone 58 and consequently pivotal movement about the pin 54 can take place until the link 52 is at the maximum permitted angle to the slider 56 when the panel 20 is in the fully upwardly pivoted position also illustrated in chain-dotted lines in Figure 1. The panel 20 can be moved back to its closed position by moving the slider 56 back to the position shown in Figure 3. The lengths of the links 44, 48 and 52 and the location of the cut-away portion 58 are chosen so that each link becomes free to move upwards only when the previous link has pivoted to its maximum extent. Figure 9 illustrates the links 44 and 48 in more detail. The link 48 has a tongue 90 which is received between shoulders 92 and 94 on the link 44. The tongue 90 has an inclided abutment surface 96 which engages with a corresponding surface 98 on the link 44 to limit the maximum angle of pivotal movement about the pin 46 which can conveniently take the form of a longitudinally slip spring pin. The various links may be formed as plastic mouldings. Figure 10 illustrates an alternative arrangement in which the links 44, 48 and 52 and the slider 56 are formed as a single plastics moulding of a material such as polypropylene with integral hinges replacing the various hinge pins. Figure 11 illustrates a third alternative in which the hinge pin 46 is replaced by a cylindrical member 100 moulded integrally with the link 44 and extending between the two shoulders 92 and 94. The tongue 96 of the link 48 is formed with a suitably shaped slot 102 which can snap over the cylindrical portion 100 as the links are assembled together. The other pivot joints are then formed in a similar manner.

Claims: CLAIMS 1. A sliding roof assembly for a motor vehicle comprising a rigid roof panel (20) which is supported at each side by front and rear guide means on respective guide tracks (26) extending along each side of an opening in the vehicle roof and behind said opening below the vehicle roof, together with means for moving the rear guide means (56) along the guide track (26), the front guide means (74) being adapted to permit pivotal movement of the panel about a horizontal axis at right-angles to the guide tracks (26) and each rear guide means comprising a guide shoe slidably received in the corresponding guide track (26) characterised in that each guide shoe (56) is connected to the roof panel by a chain of at least two links (44, 48, 52), each of the connections at the ends of the chain (42, 46, 50, 54) and between adjacent links thereof being arranged to permit relative angular movement over a limited range between an orientation such that adjacent links (44, 48, 52) are in line with each other and parallel to the guide track (26) and an orientation such that adjacent links (44, 48, 52) are at obtuse angles to each other and project above the guide track (26). 2. A roof assembly according to claim 1, characterised in that the length of the link (44) connected to the roof panel (20) is chosen so that, when said link (44) has pivoted to said obtuse angle relative to the next adjacent link (48) which has remained parallel to the guide track (26), the rear edge of the roof panel (20) is level with the adjacent vehicle roof (14). 3. A roof assembly according to claim 1 or 2, characterised in that the chain links (44, 48, 52) have formations adapted to engage with the guide track (26) so a##to to inhibit movement thereof out of line with one another when any part of the roof panel (20) is under the vehicle roof (14) behind the opening. 4. A roof assembly according to claim 3, characterised in that the length of each chain link (44, 48, 52) is chosen to be such that the formations thereon disengage from the track as the next link nearer to the roof panel (20) reaches said obtuse angle relative to such first-mentioned link. 5. A roof assembly according to claim 3 or 4, characterised in that the chain links (44, 48, 52) are of inverted T-shaped transverse cross-section, the cross-bars of the T-shape engaging under shoulders (28, 30) formed on the track (26). 6. A roof assembly according to claim 5, characterised in that the end faces of the stems of the T-shapes at each of the links (44, 48, 52) are arranged to abut against the corresponding movement to said obtuse angle. 7. A roof assembly according to claim 5 or 6, characterised in that the chain links (44, 48, 52) and the guide shoe (56) are formed as a one-piece moulding with integrally moulded hinge formations therebetween. 8. A roof assembly according to claim 4 or 5, characterised in that each link (44, 48, 52) is formed with an integrally moulded hinge pin (100) at one end and a slot (102) at the other end, the slot (102) having an enlarged inner end engaged to snap round the pin (100) of the next adjacent link. 9. A roof assembly according to any preceding claim, characterised in that the front guide means comprises support means (74) secured to the underside of the panel (20) adjacent to each of the front corners thereof and carrying a formation (78) adapted to engage with a complementary formation (70) on the track (26) which inhibits rearward movement of the panel (20) except when the rear edge thereof is in its fully lowered position below the vehicle roof (14).

Inventors: MORGAN, GEOFFREY CHARLES, WILLIAMS PHILLIP JOHN
Applicants: BRITAX WEATHERSHIELDS LIMITED
Application year: 1983
Main classification: B60J7
IPC codes: B60J7