GB2259283A

GB2259283A - A folding hood for vehicles

Info

Publication number: GB2259283A
Application number: GB9218087A
Authority: GB
Inventors: Juergen Schrader; Martin Guckel; Helmut Rottler
Original assignee: Daimler Benz AG; Mercedes Benz AG
Current assignee: Daimler Benz AG
Priority date: 1991-09-05
Filing date: 1992-08-25
Publication date: 1993-03-10
Anticipated expiration: 2012-08-25
Also published as: FR2681560A1; ITRM920626A1; GB2259283B; ITRM920626A0; IT1258469B; FR2681560B1; GB9218087D0; DE4129493C1

Description

:1 ? m C,- ^ " ' 1'-, 1 Foldincr hood for vehicles The invention relates

to a folding hood f or vehicles having a dimensionally stable rear window, which, when the hood is stowed, is foldable down from an upright position of use into a stowed position displaced to the rear, with sliding control of the rear window during the stowing operation via a strut of the hood frame, the central region of which rests against the underneath of the hood cover, in front. of the rear window.. when the hood is closed and overlaps the rear window in its swung-back end position, and having a coupling device for transmitting movement, by means of which the rear window and the strut are connected to one another, in each case at a distance from their pivot axis.

A folding hood of this kind can be taken as already known from German Offenlegungsschrift 3,416,330, the extremely large-sized rear window extending into the roof surface of the hood and sharing the tightening function of a corner strut. In accordance with its function as a supporting frame, the rear window is attached to the bodywork of the vehicle along its rear window edge by means of a rigid multi-element guide device, as a result of which the rear window can be pivoted about a horizontal transverse axis of the vehicle and is at the same time mounted in a manner which allows limited displacement towards the rear.

To stretch the hood cover over the rear window, a buckle-proof connectingrod arrangement is provided, the two connecting rods of which are each articulated on the side of the rear window and, with their opposite ends, on the associated hood pillar of a main strut. The articulation conditions of the connecting-rod arrangement are here chosen in such a way that the stowing movement of the rear window is controlled as a function of the swing-back movement of the main strut during the folding back of the hood.

Since the connecting rods are displaced forwards during the swinging back of the main strut counter to the folding direction of the latter, the first thing that 2 happens during this process is that the hood cover relaxes, with the result that the rear window is f ree. Due to the dead weight of the rear window, two plates of the guide device, connected to one another toggle- lever fashion, then f old one on top of the other, the articulatedly coupled rear window being lowered and the rear window simultaneously being displaced rearwards. As the main strut is swung back further, the forward advance of the connecting rods continues, the rear window thereby being gradually folded down into its stowed position.

In the case of the known folding hood, there is thus a direct connection between the distance by which the rear window is lowered and the distance by which it can be displaced rearwards during this process.

In order to provide a better view over the tail of the vehicle with the folding hood closed, it would be desirable per se to have the lower edge side of the rear window extend as close as possible to the material retaining profile arranged approximately at the height of the top edge of the vehicle side. since, in this case, it would not be possible to lower the rear window significantly relative to the material retaining profile, the rearward displacement of the rear window desired for reasons of space would no longer be readily achievable either.

The present invention seeks to further develop a folding hood such that rearwards displacement of the rear window into a space-saving stowed position remains possible largely independently of the amount by which the rear window is lowered relative to the material retaining profile in the course of its stowing movement.

According to the present invention there is provided a folding hood for vehicles having a dimensionally stable rear window which, when the hood is stowed, is foldable down from an upright position of use into a stowed position displaced to the rear. with sliding controlof the rear window during the stowing operation via a strut of the hood frame, the central region of which rests against the_ 3 underneath of the hood cover, in front of the rear window, when the hood is closed and overlaps the rear window in its swung-back end position, and having a coupling device f or transmitting movementi by means of which the rear window and the strut are connected to one another, in each case at a distance from their pivot axis, wherein the coupling device is a tie means unstable under bending loads, which connects the rear window in the region of its f ront window edge to the central region of the strut and becomes stable under tension only when a f inal phase of the rearward swinging movement of the strut is reached, after which the rear window participates in the rearward transverse advance of the central region and is moved positively into its pushedback end position.

The stowing movement of the rear window is expediently controlled by a corner strut of conventional type since this has the smallest pivoting angle relative to the rear window of all the struts of the hood frame. As a result, it is possible to use particularly short tie means.

A flexible control strap is particularly suitable as a tie means since it is distinguished by a low dead weight and requires only a small installation space. In contrast to link chains or link belts having a metal matrix, there is virtually no risk of scratch damage to the rear window if a control strap made of textile material is used. Control straps with a low intrinsic elongation are as such known.

Particularly with heavy rear windows made of mineral glass or the like, a uniform rearward displacement of the rear window can be ensured with an arrangement comprising a plurality of parallel control straps.

It is possible, despite the control straps, for the upper window edge of the rear window to be held up by retention straps which, crossing the central region of the corner strut, rest on the central tube and are stretched over the corner strut.

The corner strut, for its part, can advantageously be controlled automatically in its pivoting by the 4 tightening advance of positioning straps.

Particularly simple articulation of the rear window on the material holding profile which nevertheless permits rearward displacement of the rear window can be achieved by means of a narrow fabric strip of the hood cover which acts as a film hinge.

As the material retaining profile, the folding hood according to the invention can have a pivotable material retaining hoop and be capable of being retracted into an associated hood box. By virtue of the rearward displacement of the rear window in its stowed position, the opening of the hood box can here have particularly narrow dimensions and the crosssectional length of the hood box in the region in which the stowed rear window is arranged need be only slightly greater than the longitudinal extent of the rear window itself.

The control straps are preferably each formed by an extension of a retention strap, as a result of which one retention point on the rear window for common attachment is sufficient.

An illustrative embodiment of the invention is explained in greater detail below with reference to a drawing.

In this drawing: Fig. 1 shows a side view of a tail region of a convertible car with the folding hood closed, Fig. 2 shows a plan view of the hood box of the convertible car with the folding hood stowed, Fig. 3 shows a longitudinal section through the hood box, according to the line of section III-III in Fig. 2, Fig. 4 shows a perspective view of the closed folding hood from behind with a fold arrangement of the hood cover, Fig. 5 shows a section through a f abric f old of the f old arrangement, corresponding to the line V-V in Fig. 4, Fig. 6 Fig. 7 shows a longitudinal section through a control strap, according to the line VI-VI in Fig. 4 and shows the longitudinal section through the control strap with the hood stowed.

In the side view according to Fig. 1, a tail region of a convertible car 1 with a retractable folding hood 2 can be seen, comprising in a customary manner a supporting hood frame over which is stretched a flexible hood cover 3 of textile fabric of a known type.

In the rear region, the following parts of the hood frame, which is mirror-symmetrical in relation to the longitudinal median plane of the convertible car 1, can be seen: a hood pillar 4 of a main strut 5, a main connecting rod 6, a lateral roof frame 7, a material retaining hoop 8 and a corner strut 9. The lower end of the hood pillar 4 is attached to the bodywork of the convertible car 1 in a recessed manner via a main bearing 10 in the lateral leg of a hood box 11 having, overall, the shape of a U, thereby allowing the main strut 5 to be pivoted about a horizontal transverse axis of the vehicle. In the upper end region of the hood pillar 4, a rear end of the roof frame 7 is connected to the hood pillar 4 via a hinge joint 12. The roof frame 7 is retained in its design position by the associated main connecting rod 6 whose upper end is articulated on the roof frame 7 via a hinge joint 13 located at a distance in front of and, at the same time, above the hinge joint 12. The lower end of the main connecting rod 6, which extends approximately parallel to the hood pillar 4, is attached to the bodywork via a hinge bearing 14 in the hood box 11, with a similar vertical offset. Thus the roof frame 7 is guided by the hood pillar 4 and the main connecting rod 6 in the manner of a parallelogram linkage.

The upward-facing opening of the hood box 11 i closed by means of a matchingly shaped hood box lid 15, which rests on the edge of the aperture of the hood box 11 and is locked thereto in a manner not shown. on the hood box lid 15 lies the likewise U-shaped material retaining hoop 8, S 6 which forms the lower termination of the hood 2 and retains the hood cover 3 at the rear. While the hood box lid 15 is mounted behind the hood box 11 to be pivotable about an axle 16 f ixed to the bodywork, the front ends of the lateral legs of the material retaining hoop 8 are cantilever- mounted via a hinge joint 17 on the associated hood pillar 4, approximately at the height of the upper edge of the vehicle side. At the rear, the material retaining hoop 8 is locked to the hood box lid 15 by a catch arrangement (not shown) and is thus held down in its illustrated bearing position.

Above the material retaining hoop 8 is a large-sized rear window 18, inset into a rear window aperture in the hood cover 3 and retained (in a manner not shown in detail) in a window frame 19 which is connected all the way round to the hood cover 3 enclosing it. Situated above the rear window 18 is the corner contour of the hood 2, where the central tube 9a of the corner strut 9 bears supportingly on the underside of the hood cover 3. The lateral legs of the corner strut 9, which, overall, has'the shape of a U, extend approximately at right angles to the oblique plane of the rear window, forwards and downwards, and are articulated by their ends on the associated main connecting rod 6 via a hinge joint 20. The corner strut 9 is thereby supported in a manner which allows it to pivot relative to the hood cover 3 and to the main connecting rods 6. The corner strut 9 is retained in its illustrated supporting position by two positioning straps 21 of low lengthwise extensibility, each of which is connected to a f lank of the corner strut 9, extends under the hood cover 3 in the longitudinal direction of the vehicle, and is stretched forwards towards the main strut 5 and rearwards towards the material retaining hoop 8, where its respective ends are fixed. Above the rear window 18, the window frame 19 is furthermore connected to the central tube of the main strut 5 via a plurality of retention straps 21a comprising flexible bands and having similar extensibility properties to the positioning straps 21.

7 The retention straps 21a, which are likewise tautly stretched, rest on the central tube of the corner strut 9, without f ixing, and prevent the weight of the rear window 18 from having to be taken exclusively by the hood cover 3.

In order to stow the folding hood 2, it is f irst necessary to release f ront hood catches which connect the front roof part (not shown) to the windscreen frame. The locking of the material retaining hoop 8 on the hood box lid 15 is then released and the material retaining hoop 8 is swung forwards about the hinge joint 17 of the hood pillar 4, which is still upright, after which the hood box lid 15, mounted in the contrary direction, is free and, after being unlocked, can be swung upwards and rearwards into the open position indicated by broken lines. The folding hood 2 can be swung around the main bearing 10 into the open hood box 11 until it reaches its stowed position of non-use, which is shown in Fig. 3. During this procedure, the rear window 18 is folded down and stowed between the central tube of the main strut 5 and the material retaining hoop 8, after which it rests on the top of the material retaining hoop 8. As can be recognised in connection with the simplified plan view according to Fig. 2, the clear cross-section of the hood box 11 in the central region which receives the rear window 18 is only slightly longer than the rear window 18 itself. This creates the requirement that, in the course of the process of retracting the hood 2, the rear window 18 should not only be folded down along a pivot axis extending below the lower window edge but should, in addition, be displaced rearwards to the rear edge of the material retaining hoop 8, the pivot axis having to be simultaneously displaced transversely to its longitudinal extent.

The transversely displaceable axis of articulation is here formed by a narrow fabric strip 22 of the hood cover 3 itself, which acts as a film hinge. For this purpose, the fabric strip 22 is connected to the lower edge side of the rear window 18 along one lengthwise side via the window frame 19. With its opposite edge side, the fabric strip 22 8 is fixed along the underside of the material retaining hoop 8, enclosing the shaping circumference of the material retaining hoop 8 without being fixed. The shaping circumference is here considered to be the oblique circumferential surface of the material retaining hoop profile, which is wedge-shaped in crosssection, this surface extending approximately parallel to the inclination of the rear window 18 when the hood 2 is closed. During the rearward displacement of the rear window 18 relative to the material retaining hoop 8, the length of the fabric strip 22 which previously rested on the circumference of the said hoop is lifted free and guides the lower edge side of the rear window 18 rearwards, approximately parallel to the upper side of the material retaining hoop 8. It is thus possible-to dispense with additional guide devices for the lower edge side of the rear window 18.

When the hood 2 is closed, the lower corners of the rear window 18 lie very close to the upper side of the material retaining hoop 8, so that no major downward movement of the lower edge side of the rear window 18 towards the material retaining hoop 8 can take place. Instead, the free width of material of the fabric strip 22 is just sufficient to- form a reliable film hinge when the rear window 18 is folded down.

In order to ensure that no partial over-extension of the hood cover 3 can occur when the rear window 18 is displaced rearwards into its stowed position of non-use, the hood cover is provided on both sides of the rear window 18 with a fabric'zone of variable length which, when the hood cover 2 is stowed, move apart as a result of the rearward displacement of the rear window 18 relative to the material retaining hoop 8, and automatically shorten again to their initial length when the hood 2 is erected into the closed position of use.

These two fabric zones are designed as mirrorsymmetrical fabric folds 23 which, when the hood 2 is closed, are held in a tautened overlapping position by means 9 of tensile forces in the hood cover 3.

As is apparent in Fig. 4, the fabric folds 23 are each located at a lateral distance from the lower corners of the rear window 18, and extend, viewed in the vertical direction, over the width of the fabric strip 22 and a fabric region of the hood cover 3 adjacent thereto, close to the associated side edge of the rear window 18. viewed in the longitudinal direction, that is to say the direction of circumferential stress of the hood cover 3, the fabric fold 23 has its greatest fold width approximately at the height of the associated window corner, the fold width gradually decreasing both upwards and downwards.

As can been seen in connection with Fig. 5, the fabric fold 23 results in an overlap of the hood cover 3, allowing largely unhindered rearward displacement of the rear window 18.

In order to ensure that the rear window 18 is displaced positively and automatically into its end position during the process of retracting the folding hood 2, the central tube 9a of the corner strut 9 is connected via three control straps 21b to the front edge side of the rear window 18, the said straps extending parallel to one another in the longitudinal direction of the vehicle. One of these control straps 21b is connected to the window frame 19 in the middle of the width of the rear window 18 and hence f ixed to the rear window 18. The other two control straps 21b are each connected to the window frame 19 at a lateral distance from the central control strap 21b. By virtue of their arrangement, the control straps 21b are each in alignment in the longitudinal direction of the convertible car 1 with the retention straps 21a connected to the central tube of the main strut 5.

As is evident in Fig. 6, the retention straps 21a. merge integrally into the control straps 21b, the control strap 21b thereby in each case being formed by an extension of the associated retention strap 21a. In this arrangement, the transition zone between the retention strap 21a and the control strap 21b is folded over to form a loop and the loop is f ixed by a connecting seam 24 between both straps. For the purpose of attachment, the loop enfolds a U-shaped retaining hoop 25 which is connected to the window frame 19 and projects from the upper peripheral side of the latter. Via this loop connection, the rear ends of the retention strap 21a and the control strap 21b are thus f ixed on the retaining hoop 25 in a manner which is flexible but prevents axial movement. When the f olding hood 2 is closed, the retention straps 21a are stretched taut and pull the rear window 18 upwards in the direction of extension of the plane of the rear window, resting against the underneath of the likewise tautly stretched hood cover 3 and, in enfolding an upward-facing peripheral region of the strut tube 9a, rest against the corner strut 9.

To ensure that the support of the retention straps 21a on the strut tube 9a is not impaired, the front end of the control straps 21b is passed through the strut arch underneath the strut tube 9a and is connected to the strut tube 9a on the forward-facing peripheral surface by screws or other releasable fastening means.

When the hood 2 is closed, however, the control straps 21b are not stretched but have a def ined excess length which ensures that they come into action only in a final phase of the rearward swinging movement of the corner strut 9 when then hood 2 is retracted. As the hood 2 is lowered into the hood box 11, the rear window 18 is folded down onto the material retaining hoop 8 in the manner already described and the central tube of the main strut 5 laid over it. During this process, the corner strut 9 is taken along by the main connecting rods 6, which are constrained to take part in the rearward swinging movement of the main strut 5, and swung about hinge bearing 14. In order to achieve a space- saving stowed position, the corner strut 9 must furthermore be swung about the hinge joints 20, i.e. relative to the main connecting rods 6, until it lies essentially in a plane parallel to the plane of the stowed 11 rear window 18. the central tube 9a being displaced transversely rearwards in this last phase of the rearward swinging movement of the corner strut 9, in the process almost resting on the stowed rear window 18. When this last phase of the rearward swinging movement is reached, the free movement of the control straps 21b due to the excess length has, however, been used up, after which the control straps 21b are taut, such that they are stable under tension, and the central tube 9a is thus motionally coupled to the rear window 18. As a result, the rear window 18 participates in the rearward advance of the central tube 9a and is pushed back into the end position indicated in Fig. 7 and held in the latter. The slack retention straps 21a are stowed underneath the central tube 9a, on the rear window 18.

When the folding hood 2 is closed again, the main strut 5 is swung back up into its erect end position, the rear window is being taken along by the tautening retention straps 21a. After the material retaining hoop 8 has been swung up, the hood box lid 15 can be shut and the material retaining hoop 8 can then be swung back into the position in which it rests on the hood box lid 15, the distance between the central tube of the main strut 5 and the rear end of the material retaining hoop 8 increasing.

Due to this increase in the distance, the retention straps 21a and the positioning straps 21 are increasingly tightened, with the result that the corner strut 9 moves automatically into its supporting position of use due to the tightening advance of the positioning straps 21, and the rear window 18 assumes its design position. once the material retaining hoop 8 has been locked, the original position of the control straps 21b, which ensures their functionally necessary free movement, has thus been reached again too.

12

Claims

Claims

A folding hood f or vehicles having a dimensionally stable rear window which, when the hood is stowed, is foldable down from an upright position of use into a stowed position displaced to the rear, with sliding control of the rear window during the stowing operation via a strut of the hood f rame, the central region of which rests against the underneath of the hood cover, in front of the rear window, when the hood is closed and overlaps the rear window in its swung-back end position, and having a coupling device f or transm itting movement, by means of which the rear window and the strut are connected to one another, in each case at a distance from their pivot axis, wherein the coupling device is a tie means unstable under bending loads, which connects the rear window in the region of its f ront window edge to the central region of the strut and becomes stable under tension only when a f inal phase of the rearward swinging movement of the strut is reached, af ter which the rear window participates in the rearward transverse advance of the central region and is moved positively into its pushedback end position.
2. A f olding hood according to Claim 1, wherein the hood frame of the folding hood comprises a corner strut, by the central tube of which the stowing movement of the rear window is controlled.
3. A f olding hood according to Claim 1, wherein the tie means is a flexible control strap which, extending in the longitudinal direction of the vehicle, is fixed by one end to the central tube of the strut and by the other end to the front window edge of the rear window, the length of the control strap being such that it is only stretched taut when the last phase of the rearward swinging movement of the strut is reached.
4. A folding hood according to Claim 3, wherein a 13 plurality of control straps together forming the tie means are arranged distributed over the width of the rear window.
5. A folding hood according to Claim 1, 2 or 3, wherein, when the hood is closed, the rear window is supported at its upper window edge by the tensile forces of retention straps, the retention straps connecting the central tube of a main strut to the rear window and being stretched taut by virtue of support on the corner strut.
6. A folding hood according to claim 2, wherein, as the folding hood is closed, the corner strut is automatically swung into its position of use by the tightening advance of lateral positioning struts.
7. A folding hood according to Claim 1, wherein, along its lower edge side, the rear window is held by a narrow fabric strip of the hood cover which guides the rear window in the manner of a film hinge and holds it displaceably as it is folded down onto a material retaining profile forming the lower termination of the hood.
8. A f olding hood according to Claim 1, wherein the f olding hood is retractable into an associated hood box which is coverable by means of a hood box lid, a material retaining hoop pivotably mounted on the hood frame being provided as the material retaining profile.
9. A folding hood according to Claim 5, wherein each control strap is formed by an extension of a retention strap.
10. A folding hood for vehicles having a dimensionally stable rear window substantially as described herein with reference to and as illustrated in the accompanying drawings.