FR2925567A1 - Opening e.g. inclined atrium window, closure device e.g. blind, for curved frontage, has sliders with length lower or equal to sum of width of leafs such that shutter presents zigzag or rectilinear form at deployed state - Google Patents

Abstract

The device has an accordion-pleated shutter (1) formed of a succession of motorized leafs (2) articulated one with respect to another by articulation units i.e. hinges (3). Transversal edges of one leaf have supporting and guiding elements (4) i.e. rubbles, that are respectively guided by curved parallel sliders (5). The sliders are constituted of lateral posts (7) or parallel lower or upper cross pieces (12) of a peripheral frame (6). The sliders have a length lower or equal to the sum of the width of the leaves such that the shutter presents a zigzag or rectilinear form at a deployed state.

Description

The present invention relates to a closure device for closing an opening of a facade, such as a window or a door. It applies in particular, but not exclusively, to the closing of a bay by means of shutters or sliding shutters.

It is known that there are automated devices for closing openings by means of shutters or louvers generally comprising a plurality of leaves. Thus, the Applicant has proposed in the patent application FR 07 09067 a device for mechanization and motorization of sliding shutters comprising several leaves. The opening and closing of the shutter is effected by driving roller shafts or transmission ends of the end leaves by means of drive screws and / or chains arranged in the upper and lower amounts. a peripheral frame, these screws or chains being actuated by at least one motor preferably included in a lateral amount of said frame. Synchronization of the translational movement of the upper part and the lower part of the leaves is effected by means of specific transmission members.

However, this type of device is not perfectly adapted to the closing and the protection of openings included on inclined facades because in this case, the translation of the leaves of the shutters or louvers requires a greater effort.

In addition, when they are exposed to strong winds, the leaves of this type of device are often subjected to asymmetric forces that can cause unwanted movements of the flap or the corresponding louver.

The invention therefore more particularly aims to overcome these disadvantages by providing a closure device for closing and / or protect an opening of a facade that can be inclined, this device comprising a sliding shutter which includes cooperating leaves with slides so as to be deployed in a specific configuration in particular to facilitate their translation when said facade is inclined.

It proposes for this purpose a closure device comprising at least one folding shutter accordion, formed of a succession of leaves hinged to each other by their longitudinal edges by means of hinges, such as hinges, oriented parallel to the longitudinal median axis of the leaves; the transverse edges of at least one leaf comprise two respective support and guide elements guided by two respective parallel slides, each slide being common to all the support and guide elements situated on the same side of the leaves, characterized in that that the two rails constitute the two uprights or the two crosspieces of a frame and have a length less than or equal to the sum of the widths of the leaves so that in the deployed state, the shutter has a zigzag shape or rectilinear.

Preferably, the transverse edges of at least one leaf comprise two respective support and guide elements centered substantially on the longitudinal central axis of said leaf and guided by two respective parallel slides. Thus, each leaf is disposed substantially symmetrically with respect to the longitudinal median plane of said frame, namely the plane comprising the two said sleepers or both said amounts.

Advantageously, this symmetrical disposition of the leaves makes it possible in particular: to reduce the intensity of the forces necessary for the translation of the leaves intended to close off openings comprised on inclined planes, such as, for example, bay windows or inclined canopies; • offer greater strength and stability to the leaves, especially vertically oriented ones, when exposed to strong winds that can be generated by storms or cyclones, for example; in this case, the closure device according to the invention makes it possible to reduce the asymmetry of the forces exerted on the leaves, whether they are deployed totally or partially, while suppressing the unwanted movements of these leaves; • limit the efforts to be made to ensure a translation of the leaves and in particular the motorized leaves, indoor or outdoor, vertically oriented; To simplify the means for guiding the leaves and in particular vertically oriented motorized leaves, which in particular makes it possible to reduce the size of the closure device.

Advantageously, the leaves can be motorized, the support and guiding elements thus being able to cooperate with drive means connected to the output shaft of a motor or geared motor by means of transmission.

Embodiments of the invention will be described hereinafter by way of non-limiting examples with reference to the accompanying drawings, in which: FIG. 1 is a diagrammatic representation of a three-quarter view, an exploded perspective of the closure device according to the invention comprising leaves with constant width. Figure 2 is a schematic top view of leaves with variable width, at least partially deployed position, and a slide to which they are connected.

Figure 3 is a schematic representation of a three-quarter view of the closure device according to the invention closing an opening of an inclined facade.

Figures 4 and 5 are each a geometric representation 15 corresponding to the positioning, seen from above, of leaves in at least partially deployed position.

FIG. 6 is a diagrammatic representation, seen from above, of the leaves in at least partially deployed position, as well as of a slideway to which they are connected.

FIG. 7 is a schematic representation of a three-quarter view, according to an exploded perspective, of the closure device according to an alternative embodiment of the invention. Figures 8 and 9 are a view from above, according to an alternative embodiment of the invention, leaves at least partially deployed position, and a slide to which they are connected. FIG. 10 is a diagrammatic representation of a three-quarter perspective view of the closure device according to the invention in the closed position, shaped so as to be able to close and / or close an opening of a facade. curve. Figure 11 is a schematic representation, in section, of a slider shaped to allow the shutter to close and / or protect an opening of a curved facade.

In this example, as shown in FIG. 1, the closure device according to the invention comprises at least one folding shutter 1 made of accordion, formed of a succession of leaves 2 articulated to each other by their borders. longitudinal members by means of hinges 3 oriented parallel to the longitudinal median axis of the leaves 2. The transverse edges of at least one leaf 2 comprise two respective support and guide elements 4 centered substantially on the longitudinal central axis of said leaf 2 and guided by two respective parallel slides, each slide 5 being common to all the support and guide elements 4 located on the same side of the leaves 2.

These two slides 5 constitute the two crosspieces 12 of a peripheral frame 6 and preferably have a length less (or possibly equal to) the sum of the widths of the leaves 2 so that in the partially or fully deployed state, the shutter 1 has a zigzag shape (or possibly rectilinear).

The peripheral frame 6 comprises the two said parallel crosspieces 12 and two lateral uprights 7 also parallel to each other. This frame 6 is fixed to the facade comprising the opening to be closed so that the planes delimited respectively by this frame 6 and this opening are substantially parallel, the frame 6 being arranged substantially in line with the door frame of the door. opening.

In this case, the leaves 2 have a constant width, the leaves 2 being arranged vertically in order to be able to be translated in a direction substantially parallel to that of the slides 5 of said frame 6. In this case, an end leaf 2 'of each apron is articulated at its free longitudinal edge to a respective lateral upright 7 of the frame 6 by means of joints 3, such as hinges, oriented parallel to the longitudinal central axis of said leaf 2 ', this end leaf 2' preferably having a width substantially equal to half that of the other leaves 2.

However, this configuration is not limiting, the leaves 2 may for example be arranged horizontally in order to be able to move in translation along an axis substantially parallel to that of the lateral uprights 7 of said frame 6. In this case , an end leaf 2 'of each apron is articulated at its free longitudinal edge to an upper or lower cross member 12 of the frame 6 by means of joints 3, such as hinges, oriented parallel to the longitudinal central axis leaves 2, the two said slides 5 then constituting the two lateral uprights 7 of the frame 6.

The deck constituted by the leaves 2 hinged to each other can be connected to another deck of the aforesaid type (not shown in Figure 1) hinged to the lateral upright 7 (or a cross member 12) opposite. These two aprons are connected at the level of the free longitudinal edge 8 of their leaf 2 "located opposite the other end leaf 2 'connecting the apron corresponding to the frame 6. These two longitudinal edges 8 may have a conformity of form in order to be embedded in one another at the end of the aprons stroke, which allows in particular to seal the assembly.

Said end leaf 2 "preferably has a first portion 100 having a width substantially equal to half that of the intermediate leaves 2, this width corresponding to the distance separating the axis of rotation of the support and guide elements 4 connected to the transverse edges of this end leaf 2 ", the axis of articulation connecting the end leaf 2" to the leaf 2 adjacent thereto.

As shown in FIG. 8, this end leaf 2 "may also comprise a second portion 101 that may have a variable width, this second portion 101 extending said first portion 100 and has at its free end said longitudinal edge 8.

According to an alternative embodiment of the invention, as shown in FIG. 6, each end leaf 2 "comprises only a first part 100 of the aforesaid type having at its free end a joining profile 3a. which extends in the longitudinal median plane of the frame 6. This junction profile 3a is itself prolonged by a free longitudinal border 8 of the aforesaid type which has a conformal shape with the corresponding longitudinal edge 8 of the other deck. These profiled junction assemblies 3a - longitudinal edges 8, which extend in the longitudinal median plane of the frame 6, allow to connect the two aprons.

Said support and guide elements 4 may consist in particular of rollers which are each centered substantially on the longitudinal median axis of a leaf 2 corresponding, these support and guide elements 4 to ensure the rotation of the leaves 2 compared to the framework 6.

In this way, the leaves 2 are disposed substantially symmetrically with respect to the plane comprising the axes of rotation of the support and guide elements 4 which substantially corresponds to the longitudinal median plane of the frame 6. The hinge axes of the leaves 2 hinged together the others are thus arranged on either side of said plane and are no longer, as is the case with conventional shutters or shutters, substantially coincident with said axes of rotation of the support elements and guide 4. This provision advantageously makes it possible to balance the masses on either side of this plane.

Preferentially. the end leaf 2 'which is articulated to a lateral upright 7 (or to a cross member 12) of the frame 6, does not comprise support and guiding elements 4. Moreover, these support and guide elements 4 may not always be centered on the longitudinal median axis of some leaves 2.

In addition, as shown in Figure 2, the leaves 2 may not have an equal width. The support and guide elements 4 are in this case positioned on a leaf 2 depending on the cooperating width of the neighboring leaf 2, namely the distance separating the axis of rotation of the support and guide elements 4 included on this leaf. neighbor 2, the joint axis common to the two said neighboring leaves 2.

In this way, it is possible to control the mobility of the support and guide elements 4 of the intermediate leaves 2 from the position of the support and guide elements 4 of the end leaf 2 "situated opposite to that 2 'fixed to the lateral upright 7.

Indeed, as shown in FIG. 4, which is a simplified geometrical representation corresponding to the positioning, seen from above, of leaves 2 in vertical position, the axes of rotation of the support and guiding elements 4 and the axes of rotation. articulation of the leaves 2 intersect the plane [H] perpendicular to the longitudinal median plane [V] of the frame 6, at respective points a, c, e, g, h and b, d, f. These points constitute the vertices of a series of isosceles triangles T1, T2, T3 (or T4) whose bases are situated on the line of intersection (D) between the longitudinal median plane [V] of the peripheral frame 6 and said plane transverse [H]. Each of these isosceles triangles always has an angle (for example c 1) of its base opposed by its vertex at an angle (for example c2) of the base of the adjacent triangle extending in the opposite direction. In this way, all these isosceles triangles are of equal dimensions or are at least similar in the case where the leaves 2 would not have an identical width.

This geometric configuration implies that if any two points of the vertexes of the bases of the triangles belonging to the intersection line (D) are fixed (for example, the points a and g) then all the triangles are fixed. In other words, if the points a and g respectively correspond to the hinge axis of the end leaf 2 'connected to a lateral upright 7 and to the axis of rotation of the support and guide elements 4 of the other end leaf 2 ", these points a and g can then be fixed when these support and guiding elements 4 will for example be locked in translation by a drive system with which they cooperate, which will freeze in position the shutter 1, the geometric arrangement of the leaves 2, 2 ', 2 "thus remaining very stable.

This stability of the arrangement of the leaves 2 is particularly advantageous in the event that the shutter device according to the invention is installed in windy or cyclonic regions or is used, as shown in FIG. 3, to seal and to protect canopies included on inclined roofs, the specific geometric configuration of the leaves 2 having the same interest when the opening to be closed is included on an inclined facade. This geometric configuration of the leaves 2, which gives the deployed deck a symmetrical and regular geometric shape, therefore allows in particular to open at least partially the shutter 1 without the leaves 2 are subject to inadvertent movements under the action of the wind .

By way of comparison, FIG. 5 represents a geometric layout corresponding to the positioning, seen from above, of leaves 2 of a conventional shutter, such as a shutter. In this case, the axes of rotation of the support and guide elements 4 are substantially merged with the hinge axes of the leaves 2. Thus, if the points a 'and e' are fixed (these points respectively corresponding to the axis of articulation of the end leaf 2 'connected to the frame 6 and to the axis of rotation of the support and guide elements 4 of the other end leaf 2 "), each isosceles triangle formed by a cross section of the leaves 2 may have a vertex c 'of its base which moves along the intersection line (D'), which affects the stability of the assembly.

Generally, with the exception of the end leaves 2 ', 2 ", each leaf 2 comprises two supporting and guiding elements 4 respectively connected to the upper and lower transverse edge of said leaf 2. However, preferably, when the opening to be closed is included on an inclined facade, all the leaves 2, 2 ', 2 "each comprise two support and guide elements 4 connected to the respective upper and lower transverse edges.

The number of leaves 2, 2 ', 2 "per deck can be even or odd.

According to an alternative embodiment of the invention, as shown in Figures 7 to 9, the leaves 2, 2 ', 2 "are articulated to each other by their longitudinal edges by means of junction profiles 3' oriented parallel to the longitudinal median axis of the leaves 2, 2 ', 2 ", these junction profiles 3' constituting joints 3. Thus, these junction profiles 3 'extend on either side of the longitudinal median plane of the frame 6, so that their axes are preferentially at equal distance from said median plane. The aprons composed of these leaves 2, 2 ', 2 "can thus notably allow to close openings included on inclined facades.

Advantageously, the leaves 2 can be motorized, said support and guide elements 4 can thus cooperate with drive means connected to the output shaft of an engine by transmission means.

Preferably, the support and guiding elements 4 cooperating with said drive means are those connected to the upper and / or lower transverse edges of each end leaf 2 ". Nevertheless, according to an alternative embodiment of the invention, the support and guide elements 4 of the intermediate leaves 2 can all cooperate with said drive means.

The same leaf 2 can be driven: by a single support and guide element 4 connected to one of its transverse edges; By two support and guide elements 4 connected respectively to its upper and lower transverse edges.

The choice of the methods of driving a leaf 2 depends on various parameters such as in particular: • the dimensions and the quantity of the leaves 2 of the shutter 1; • the angle of inclination of the shutter 1; The specificity of the means used for the articulation of the leaves 2 between them and the support and guide elements 4.

In addition, according to an alternative embodiment of the invention, the driving of the leaves 2, 2 ', 2 "can be carried out at the level of the support and guide elements 4 or at the level of said longitudinal edges 8 of the leaves of the door leaf. 'end 2'.

Preferably, according to an alternative embodiment of the invention, said drive means may comprise: • at least one drive screw extending longitudinally in the element of the frame 6 constituting a slide 5; At least one nut cooperating with the drive screw, this nut being in engagement with at least one of the support and guide elements 4. In addition, each of the drive screws comprises, on at least one corresponding length. the running of aprons, a net having a specific pitch that is adapted to the direction and speed of movement of the aprons.

Assuming that these drive means comprise two drive screws included in two crosspieces 12 (or two uprights 7) opposite, the transmission and the synchronization of the translation of the aprons are made by means of at least one axis included in one of the uprights 7 (or respectively in one of the crosspieces 12) of the frame 6, this axis and the screws having at their ends, which preferably extend in the corners of the frame 6, means such that gears which cooperate with one another to form a gearbox mechanism.

According to an alternative embodiment of the invention, the transmission as well as the synchronization of the translation of the aprons are carried out by means of at least one chain or a transmission belt included in one of the uprights 7 (or in the one of the crosspieces 12) of the frame 6, this chain or belt being actuated by pinions or toothed wheels connected to the ends of the drive screws.

In this way, the movement of the output shaft (s) of the motor or gear motor is transmitted to the drive means via the transmission means comprising: said axis and said gears; or • said transmission chain or belt, and said pinions or toothed wheels.

According to another alternative embodiment of the invention, the slides 5 may be shaped to allow the shutter 1 to close and / or protect an opening of a curved facade, such as for example a curved bay.

Thus, as shown in FIGS. 10 and 11, the slides 5 may be curved and may include, for example: • two opposing folds 120 extending at the respective ends of the lateral sides of the slides 5, which define the internal border of the frame 6, these folds 120 delimiting a first longitudinal slot 121 in which can engage support and guide elements 4 or one end of a longitudinal edge assembly 8 - junction profile 3a • two fins 122 each connected at one of their ends to the inner face of a respective fold 120 so as to be equidistant from said first longitudinal slot 121, each fin 122 extending substantially perpendicular to the corresponding fold 120; Two other fins 123 each connected at one of their ends to the internal face of the side opposite to that where said folds 120 extend, each of these fins 123 being substantially coaxial with a respective fin 122 connected to one said folds 120.

In this way, each pair of coaxial fins 122, 123 delimits, with one of the corresponding lateral sides of the slideway 5, a space in which may be arranged a preferably roller chain or a toothed or perforated belt (not shown), the upper end of each support member 4 or a connecting profile 3a being connected to this chain or belt which is itself directly or indirectly connected to the output shaft of an engine or a motorcycle - gearbox.

In this way, the movement of the drive means, which is constituted in this case by the chain or the belt, is transmitted to the support and guide elements 4 or to a longitudinal edge 8, which allows a translation of the aprons. .

Claims (20)

claims 1. Shutter device comprising at least one shutter (1) folding accordion formed of a succession of leaves (2) articulated to each other by their longitudinal edges by means of joints (3) oriented parallel to the longitudinal median axis of the leaves (2); the transverse edges of at least one leaf (2) comprise two respective support and guiding elements (4) guided by two respective parallel slides (5), each slide (5) being common to all the support and guiding elements. (4) located on the same side of the leaves (2), characterized in that the two rails (5) constitute the two uprights (7) or the two crosspieces (12) of a frame (6) and have a length less than or equal to the sum of the widths of the leaves (2) so that in the expanded state, the shutter (1) has a zigzag or rectilinear shape. 2. Shutter device according to claim 1, characterized in that the transverse edges of at least one leaf (2) comprise the two said support and guide elements (4) respectively centered substantially on the longitudinal center axis of said leaf (2). 3. Shutter device according to claim 2, characterized in that each leaf (2) is disposed substantially symmetrically with respect to the longitudinal median plane of the frame (6) namely the plane comprising the two said sleepers (12) or both said amounts (7). 25 4. Shutter device according to one of claims 2 and 3, characterized in that the peripheral frame (6) comprises the two parallel crosspieces (12) and two lateral uprights (7) also parallel to each other; this frame (6) is fixed to the facade comprising the opening to be closed in such a way that the planes delimited respectively by this frame (6) and this opening are substantially parallel, the frame (6) being disposed substantially at the right of the doorframe of the opening. 5. Shutter device according to one of claims 2 to 4, characterized in that the leaves (2) are arranged vertically in order to be able to move in translation along an axis substantially parallel to that of the slides. (5) said frame (6); in this case, an end leaf (2 ') of each apron is articulated at its free longitudinal edge to a respective lateral upright (7) of the frame (6) by means of articulations (3) oriented parallel to the longitudinal central axis of the leaves (2), the said two slides (5) then constituting the two crosspieces (12) of the frame (6). 6. Shutter device according to one of claims 2 to 4, characterized in that the leaves (2) are arranged horizontally in order to be able to move in translation along an axis substantially parallel to that of the amounts lateral (7) of said frame (6); in this case, an end leaf (2 ') of each apron is articulated at its free longitudinal edge to an upper or lower cross member (12) of the frame (6) by means of articulations (3) oriented parallel to the longitudinal central axis of the leaves (2), the two said slides (5) then constituting the two lateral uprights (7) of the frame (6). 7. Shutter device according to one of claims 5 and 6, characterized in that the apron constituted by the leaves (2) hinged to each other is connected to another apron of the aforesaid type hinged to the lateral upright (7) , or to a cross member (12), opposite; these two aprons are connected at the free longitudinal edge (8) of their leaf (2 ") respectively located opposite the other end leaf (2 ') connecting the apron corresponding to the frame (6) these two longitudinal edges (8) having a conformal shape so as to be able to fit into one another at the end of travel of the aprons, which makes it possible to seal the assembly. 8. Shutter device according to claim 7, characterized in that the end leaf (2 ") has a first portion (100) having a width substantially equal to half that of the intermediate leaves (2), this width corresponding to the distance separating the axis of rotation of the support and guiding elements (4) connected to the transverse edges of this end leaf (2 "), of the axis of articulation connecting this end leaf (2 ") to the leaf (2) adjacent thereto, this end leaf (2") comprises a second portion (101) may have a variable width, the second portion (101) extending said first portion (100) and comprises its free end said longitudinal edge (8). 9. Shutter device according to claim 8, characterized in that each end leaf (2 ") comprises only a first portion (100) of the aforesaid type having at its free end a joint profile (3a) extending in the longitudinal median plane of the frame (6), this joining profile (3a) is itself extended by a free longitudinal edge (8) of the aforesaid type which conforms in shape with the longitudinal edge (8). ) corresponding to the other apron, these profiled junction assemblies (3a) longitudinal edges (8), which extend in the longitudinal median plane of the frame (6), allow to connect the two aprons. 10. Shutter device according to one of claims 2 to 9, characterized in that the support and guiding elements (4) are constituted by rollers which are each centered substantially on the longitudinal central axis of a leaf (2) corresponding, these support elements and guide (4) for ensuring the rotation of the leaves (2) relative to the frame (6); in addition, the hinges are constituted by hinges (3) or joining profiles (3 '). 11. Shutter device according to one of claims 6 to 10, characterized in that the end leaf (2 ') which is articulated to a lateral upright (7), or to a cross member (12), of the frame (6), does not include support and guide elements (4). 12. Shutter device according to one of claims 7 to 11, characterized in that the leaves (2) have a constant width, the end leaves (2 ', 2 ") having a width substantially equal to half that of the intermediate leaves (2). 13. Shutter device according to one of claims 2 to 11, characterized in that the leaves (2) do not have an equal width; the support and guide elements (4) are in this case positioned on a leaf (2) depending on the cooperating width of the neighboring leaf (2), namely the distance separating the axis of rotation of the support elements and guide (4) included on the neighboring leaf (2), the joint axis common to the two neighboring leaves (2). Closing device according to one of the preceding claims, characterized in that the leaves (2) are motorized, said supporting and guiding elements (4) being able to cooperate with drive means connected to the control shaft. output of an engine or a motorcycle or gearbox by transmission means. Closure device according to one of Claims 8 to 14, characterized in that the leaves (2, 2 ', 2 ") are driven at the level of the supporting and guiding elements (4). Shut-off device according to one of Claims 14 and 15, characterized in that the drive means comprise: • at least one drive screw extending longitudinally in the frame element (6) constituting a slider (5) • at least one nut cooperating with the drive screw, this nut being engaged with at least one of the support and guide elements (4); in addition, each of the driving screws comprises, on at least one length corresponding to the stroke of the aprons, a net having a specific pitch which is adapted to the direction and speed of movement of the aprons. Shutter device according to Claim 16, characterized in that the drive means comprise two drive screws comprised in two crosspieces (12), or two opposite uprights (7), the transmission and the synchronization of the translation of the aprons are carried out by means of at least one axis included in one of the uprights (7), or respectively in one of the crosspieces (12), of the frame (6), this axis and the screws comprising at their ends, which extend in the corners of the frame (6), means such as gears which cooperate with each other to form a gearbox mechanism. 18. Shutter device according to claim 16, characterized in that the drive means comprise two drive screws included in two sleepers (12), or two uprights (7), opposite, the transmission and the synchronization of the translation of the aprons are carried out by means of at least one chain or a transmission belt included in one of the uprights (7), or in one of the crosspieces (12), of the frame (6), this chain or this belt being actuated by pinions or toothed wheels connected to the ends of the drive screws. 19. Shutter device according to one of claims 17 and 18, characterized in that the movement of the output shaft (s) of the motor or the motorcycle-gearbox is transmitted to the drive means by means of transmission means comprising: said axis and said gears; or • said transmission chain or belt, and said pinions or toothed wheels. 20. Shutter device according to one of claims 18 and 19, characterized in that the slides (5) are curved and comprise: two opposing folds (120) extending at the respective ends of the lateral sides of the slides (5). ), which define the internal border of the frame (6), these folds (120) defining a first longitudinal slot (121) in which can engage support and guide elements (4) or one of the ends of a longitudinal edge assembly (8) -connected profile (3a); Two fins (122) each connected at one of their ends to the inner face of a respective fold (120) so as to be equidistant from said first longitudinal slot (121), each fin (122) extending substantially perpendicular to the corresponding fold (120); Two other fins (123) each connected at one of their ends to the internal face of the side opposite to that where said folds (120) extend, each of these fins (123) being substantially coaxial with a fin (122); ) respectively connected to one of said folds (120); in this way, each pair of coaxial fins (122, 123) defines with one of the corresponding lateral sides of the slide (5) a space in which a preferably roller chain or a toothed or perforated belt may be arranged, the upper end of each support member (4) or a connecting profile (3a) being connected to this chain or belt which is itself directly or indirectly connected to the output shaft of an engine or a motorcycle - gearbox.