WO2024110925A1

WO2024110925A1 - Balustrade assembly

Info

Publication number: WO2024110925A1
Application number: PCT/IB2023/061861
Authority: WO
Inventors: Giordano Bonomi
Original assignee: Metalglas Bonomi S.R.L.
Priority date: 2022-11-25
Filing date: 2023-11-24
Publication date: 2024-05-30

Abstract

A balustrade assembly (1) comprising: 1) a slab (2), made of glass, which extends planarly, comprising a first slab face (21) and a second slab face (22), and a slab foot (23); ID a supporting device (3) comprising a base (30), a first wing (31), and a second wing (32), which extend from said base (30) identifying a cavity (300) therebetween in which the slab foot (23) is insertable; ill) an adjustment/blocking group (4) suitable for blocking the slab (2) in the supporting device (3), wherein the adjustment/blocking group (4) comprises at least one adjustment/blocking device (5, 6, 7) housed in said cavity (300) between the first slab face (21) and the first wing (31). Said supporting device (3) comprises a thrust fin (320), included in the second wing (32), positioned in a region opposite to the adjustment/blocking group (4), wherein said thrust fin (320) is positionable in a position suitable for recovering the inclination of the slab (2).

Description

BALUSTRADE ASSEMBLY

DESCRIPTION

[0001] The present invention relates to a balustrade assembly comprising a slab made of glass.

[0002] In the prior art solutions, assembly solutions of said type are known.

[0003] A typical problem of such solutions is that of having to securely lock said slab made of glass to the supporting device in such a way as to obviate the possibility that said slab may come out of the supporting device, thus representing a potential dangerous situation .

[0004] A further problem addressed by these solutions is that of adjusting the position of the slab to position it in a desired, plumb position.

[0005] In this context, solutions are known in which, by means of complex blocking systems, the slab is securely adjusted and fixed to the supporting device.

[0006] The re is therefore a particularly strong need to have balustrade assembly solutions that respond to the aforementioned needs by providing supporting devices and adj ustment/blocking groups with simple geometry and simple interactions with the slab compared to prior art solutions .

[0007] This object is achieved by means of the balustrade assembly claimed in claim 1. The claims that are dependent upon these claims describe preferred variant embodiments involving further advantageous aspects.

[0008] Further features and advantages of the invention will become clear from the description given below of its preferred embodiments as non-limiting examples, in reference to the attached figures, wherein:

- Figures 1 and 1' represent a perspective view with separate parts of a balustrade assembly according to the present invention and a partial assembled view thereof, respectively, according to a first embodiment;

- Figures 2' , 2", 2’ ’ ’ show the balustrade assembly referred to in Figure 1 in three distinct transversal section planes;

- Figures 3 and 3' represent a perspective view with separate parts of a balustrade assembly according to the present invention and a partial assembled view thereof, respectively, according to a second embodiment;

- Figures 4' , 4", 4' ’ ’ show the balustrade assembly referred to in Figure 2 in three distinct transversal section planes;

- Figures 5 and 5' represent a perspective view with separate parts of a balustrade assembly according to the present invention and a partial assembled view thereof, respectively, according to a third embodiment; - Figures 6 ' , 6" show the balustrade assembly referred to in Figure 5 in two distinct transversal section planes ;

- Figures 7 and 7 ' represent a perspective view with separate parts of a balustrade assembly according to the present invention and a partial assembled view thereof , respectively, according to a fourth embodiment ;

- Figures 8 ' , 8" , 8 ' ' ' show the balustrade assembly referred to in Figure 7 in three distinct transversal section planes ;

- Figure 9 is a sectional view of a balustrade assembly according to the present invention, according to a fi fth embodiment ;

Figures 10a, 10b and 10c illustrate a supporting device , included in the balustrade assembly, in section in a starting position, a schematic angled position, a final angled position, respectively;

- Figures I la, 11b and 11c illustrate a supporting device and a slab, included in the balustrade assembly, in section in a starting position, a schematic angled position, a final angled position, respectively;

- Figure 12 shows a perspective view of the supporting device , included in the balustrade assembly, according to a first embodiment ;

- Figures 13 and 13a show a perspective view and a side view of an adj ustment/blocking device included in the balustrade assembly according to a first embodiment ;

- Figure 14 and 14a show a perspective view and a side view of an adj ustment/blocking device included in the balustrade assembly according to a first embodiment ;

- Figures 15 and 15a show a perspective view and a side view of an ad ustment/blocking device included in the balustrade assembly according to a third embodiment ;

- Figures 16a, 16b, 16b' show a perspective view and a side view of the components that make up an adj ustment/blocking device included in the balustrade assembly according to a fourth embodiment ;

- Figure 17 shows a sectional view of a balustrade assembly, respectively according to the present invention, according to a sixth embodiment ;

- Figure 18 shows a sectional view of a balustrade assembly according to the present invention, according to a seventh embodiment ;

- Figure 19 shows a sectional view of a balustrade assembly according to the present invention, according to an eighth embodiment ;

Figure 20 shows a perspective view of a balustrade assembly, according to the present invention, according to a ninth embodiment ;

Figure 21 shows a sectional view of the balustrade assembly according to the embodiment of Figure 20 ; Figure 22 shows a perspective view of a balustrade assembly, according to the present invention, according to a tenth embodiment;

- Figure 23 shows a sectional view of the balustrade assembly according to the embodiment of Figure 22.

[0009] With reference to the accompanying figures, reference numeral 1 indicates a balustrade assembly according to the present invention.

[0010] Preferably, such balustrade assembly 1 is mountable to a surface, for example a floor or a wall extending in height.

[0011] For example, such balustrade assembly may constitute a parapet, a balustrade or a screen. For example, such balustrade assembly 1 may constitute a shelter .

[0012] According to the present invention, the balustrade assembly 1 comprises a slab 2 made of glass. The slab 2 extends planarly comprising a first slab face 21 and a second slab face 22.

[0013] Furthermore, the slab 2 defines a slab plane L.

[0014] The slab 2 comprises a slab foot 23 which, as described below and shown in the accompanying figures, is specifically engageable by a supporting device 3.

[0015] Preferably, the slab 2 has variable dimensions, and the dimensions of the slab 2 do not limit the present invention .

[0016] According to a preferred embodiment, the slab 2 is a multilayer slab consisting of at least two layers of glass (as shown by way of example in the accompanying figures) .

[0017] According to the invention, the balustrade assembly 1 comprises a supporting device 3 comprising a base 30, a first wing 31 and a second wing 32 which extend from said base 30 identifying a cavity 300 therebetween. Said slab foot 23 is insertable into said slab foot 300.

[0018] According to a preferred embodiment, the supporting device 3 therefore has a substantially U- shaped section.

[0019] According to a preferred embodiment, the supporting device 3 extends in length along a longitudinal axis X-X.

[0020] Preferably, the supporting device 3 may be placed on a surface.

[0021] Preferably, the supporting device 3 is housed in a surface .

[0022] According to a preferred embodiment, the longitudinal length of the supporting device 3 is equal to that of the slab 2. However, in some embodiments the supporting device 3 has a greater extension than that of a slab 2, being suitable, for example, to support more than one slab 2.

[0023] According to an embodiment variant, however, the supporting device 3 has a smaller extension than that of a slab 2.

[0024] According to a preferred embodiment, a plurality of supporting devices 3 are longitudinally aligned.

[0025] According to an embodiment, the supporting device 3 comprises fixing means 10 suitable for fixing the balustrade assembly 1 to a surface. For example, such fixing means 10 comprise a threaded bar 11 and a nut 12 mutually engageable by screwing and engaging the base 30. [0026] According to the present invention, the supporting device 3 comprises a thrust fin 320.

[0027] Preferably, the thrust fin 320 is positionable in an angled position to recover the inclination of the slab 2.

[0028] In other words, the thrust fin 320 has limited thicknesses to flex, at least in part, following a thrust action .

[0029] Preferably, the thrust fin 320 performs a thrust action on the slab 2.

[0030] According to a preferred embodiment, the thrust fin 320 in fact in an unbiased, starting position is positioned protruding towards the interior of the cavity 300.

[0031] Preferably, therefore, in order to align the slab 2 in an orthogonal position (also known to professionals as "plumb") it is necessary to perform a thrust action on the thrust fin 320 and force it into a flattened or angled position.

[0032] According to a preferred embodiment, the thrust fin 320 has a thickness that allows it to bend. Preferably, the thrust fin 320 comprises a thinned portion suitable for facilitating the bending of the thrust fin 320.

According to a preferred embodiment, the thrust fin 320 has a geometry that allows it bend.

[0033] Preferably, the thrust fin 320 has a prevalent dimension in the vertical direction.

[0034] Preferably, the thrust fin 320 has a reduced transverse dimension, or thickness.

[0035] According to a preferred embodiment, the thrust fin 320 is made of a material that allows it to bend.

[0036] According to a preferred embodiment, said thrust fin 320 is positioned in an opposite region with respect to the base 30 in the second wing 32.

[0037] According to a preferred embodiment, the supporting device 3 is a component made in one piece, preferably obtained by extrusion, which extends along a longitudinal axis X-X, so that the thrust fin 320 is an integral part of the second wing 32. In other words, in this embodiment, the thrust fin 320 is of one piece, or integral, with the second wing 32. Preferably, the thrust fin 320 is obtained in the extrusion operation through which the supporting device 3 is obtained.

[0038] According to an embodiment variant, the thrust fin 320 is removably mountable, preferably in an appropriate cavity 329 of the second wing 32.

[0039] In other words, in this embodiment, the thrust fin 320 is mountable/removable as necessary.

[0040] Preferably, the thrust fin 320 is snap-mountable to the second wing 32.

[0041] According to a preferred embodiment, illustrated by way of example in Figure 23, the supporting device 3 comprises an intermediate body 33 housed in the cavity 300, preferably comprising an outer surface having a shape, at least partially, complementary to the base 30 and/or to the first wing 31 and/or to the second wing 32. [0042] In this embodiment, the thrust fin 320 is included in said intermediate body 33. In other words, the thrust fin 320 is returned to the support device 3.

[0043] Preferably, the support foot 9 is supported by the intermediate body 33.

[0044] Preferably, the intermediate body 33 is made of a metal alloy, for example in folded sheet metal or by extrusion .

[0045] According to a preferred embodiment, the intermediate body 33 is configured to collect and convey waste water, i.e. it acts as a drainage channel.

[0046] According to a preferred embodiment, the thrust fin 320 extends along the entire longitudinal axis X-X.

[0047] According to a further embodiment, the thrust fin 320 comprises a plurality of thrust sections aligned along the longitudinal axis X-X.

[0048] According to a preferred embodiment, the second wing 32 comprises a thrust compartment 325 positioned in an opposite region with respect to the cavity 300, wherein the thrust fin 320 in the angled/bent configuration is housed in said thrust compartment 325.

[0049] According to a preferred embodiment, transversely to the thrust fin 320 there is a hollow space (the thrust compartment 325) in which the thrust fin 320 may be housed in the angled/bent configuration under the action of the slab 2. Preferably, the thrust fin 320 is positioned between the thrust chamber 325 and the cavity 300. Preferably, the thrust compartment 325 is a hollow space delimited transversally between the thrust fin 320 and an inner surface 322 of the second wing 32 facing the thrust fin 320 and the cavity 300. [0050] According to a preferred embodiment, the balustrade assembly 1 comprises an elastically yielding backing element 8, engaged with the thrust fin 320, suitable for coming into contact with the slab 2.

[0051] Preferably, said backing element 8 is made of a soft material, for example rubber.

[0052] According to a preferred embodiment, the backing element 8 is shaped to embrace the upper end of the thrust fin 320 being housed with a first portion 81 in the cavity 300 and with a second portion 82 in the thrust compartment 325.

[0053] Preferably, the backing element 8 is substantially inverted U- or C-shaped, to house the thrust fin 320 at its interior.

[0054] According to a preferred embodiment, the backing element 8 is elastically yielding so that the second portion housed in the thrust compartment 325 allows angling the thrust fin 320 while avoiding its buckling.

[0055] In other words, the backing element 8 has a dual function: to facilitate the engagement of the thrust fin 320/slab 2, avoiding breakage of the slab, and to avoid excessive bending of the thrust fin 320 and therefore its breakage .

[0056] In other words, the U shape and the presence of the first portion 81 and the second portion 82 brings a plurality of advantages to the backing element.

[0057] According to a preferred embodiment, the backing element 8 is made up of two distinct components, a first element which engages the slab 2 and a second element 89 which avoids excessive bending of the thrust fin 320 and therefore its breakage. Preferably, said second element 89 is also elastically yielding or has a shape which may be modified depending on its position, in such a way as to provide a backing to the thrust fin 320, avoiding its excessive bending.

[0058] According to a preferred embodiment, the second element 89 is at least partially housed in the thrust compartment 325.

[0059] According to a preferred embodiment, the second element 89 extends mainly along the longitudinal axis X- X.

[0060] According to a preferred embodiment, the second element 89 is designed to remain elastically undeformed during the elastic deformation of the thrust fin 320, preferably it is made of a rigid material, for example metal or metal alloy .

[0061] According to a preferred embodiment, the second element 89 has a reduced transversal dimension, for example less than one centimeter, for example less than 0.5 centimeters, for example equal to approximately 0.4 centimeters .

[0062] Preferably, the second element 89 has a circular section on a sectional plane transversal to the longitudinal axis X-X.

[0063] According to a preferred embodiment, the second element 89 is rod-shaped, for example is a bar.

[0064] According to a preferred embodiment, the second element 89 is positioned transversally in contact with the inner surface 322 of the second wing 32.

[0065] According to a preferred embodiment, the inner surface 322 of the second wing 32 comprises a backing projection 323, for example made in a single piece with the wing 32, protruding into the thrust compartment 325. The second element 89 is positioned against said backing projection 323, thus maintaining a predefined fixed position in the thrust compartment 325.

[0066] According to a preferred embodiment, the second element 89 is configured to reduce the bending arm of the thrust fin 320, when placed in mutual contact.

[0067] According to a preferred embodiment, along the vertical direction, the second element 89 is positioned in a central region of the thrust fin 320 comprised between 20% and 80% of the vertical dimension, or height, of the thrust fin 320.

[0068] According to a preferred embodiment, the thrust fin 320 is detached transversally from the second element

89 in the starting position, and is in contact with the second element 89 in a transverse direction in the final angled position .

[ 0069 ] During the elastic deformation between the starting position and the final angled position, the thrust fin 320 performs a movement towards the second element 89 in a transverse direction, for example due to the thrust action of the slab 2 . During this approach movement , being entirely free to deform elastically, the thrust fin 320 of fers a first resistance against the movement of the slab 2 . Once the second element 89 has been reached, the thrust fin 320 has a smaller bending arm defined by contact with the second element 89 . Therefore , the thrust fin 320 of fers a second resistance against the movement of the slab 2 , greater than the first resistance .

[ 0070 ] According to a preferred embodiment , the thrust fin 320 is positioned in contact with the second element 89 in a transverse direction, both in the starting position and in the final angled position .

[ 0071 ] Furthermore , according to the present invention, the balustrade assembly 1 comprises an adj ustment/blocking group 4 housed in said cavity 300 to engage the slab 2 and the supporting device 3 in mutual locking .

[0072] In particular, the adj ustment/blocking group 4 housed in the cavity 300 on the opposite side to that where the thrust fin 320 is located.

[0073] Preferably, the ad ustment/blocking group 4 is suitable for performing an opposite action on the slab 2 with respect to the action of the thrust fin 320.

[0074] Preferably, the adj ustment/blocking group 4 is suitable for performing an action controlled and adjustable by the user on the slab 2. Preferably, the adj ustment/blocking group 4 is suitable for maintaining the action set by the user over time.

[0075] Preferably, the fin 320 is suitable for providing backing to the action produced by the adj ustment/blocking group 4 on the slab 2.

[0076] The adj ustment/blocking group 4 comprises at least one adj ustment/blocking device 5, 6, 7.

[0077] The adj ustment/blocking device 5, 6, 7 has different embodiments, which may be used separately or simultaneously, as shown by way of example in the accompanying figures.

[0078] According to a preferred embodiment, the adj ustment/blocking device 5 comprises: a pair of gibs 51, 52, wherein each gib 51, 52 comprises an outer surface 511, 521 suitable for being engaged with the supporting device 3 or the slab 2, respectively, and an inner surface 512, 522 comprising a housing 510, 520 delimited at the top by an inclined wall 510' , 510";

- a control member 53 comprising an upper block 531, a lower block 532, and at least one screw element 535 engaged with the upper block 531 and the lower block 532. [0079] Preferably, upon the rotation of the at least one screw element 535, the upper block 531 and the lower block 532 are moved either away from or towards each other while the two gibs are moved either away from or towards each other.

[0080] The action of the gibs expresses a thrust action on the slab 2 to block it in a preferred position.

[0081] The action of the gibs expresses a thrust action on the slab 2 to adjust the angular position thereof.

[0082] Different embodiments and shapes of the gibs correspond to forces of different types/directions/intensities .

[0083] According to a further embodiment, the ad ustment/blocking device 6 comprises:

- a first wedge-shaped element 61 comprising a planar surface 610 which engages the first slab face 21, and an inclined surface 611 opposite to the planar surface;

- a second wedge-shaped element 62 comprising a planar surface 620 which engages the first wing 31, and an inclined surface 621 opposite to the planar surface.

[0084] According to a preferred embodiment, the first wedge-shaped element 61 and the second wedge-shaped element 62 are mutually engaged by means of the two inclined walls 611, 621.

[0085] Preferably, a different relative position of the two wedge-shaped elements 61, 62 corresponds to a different thrust and a different position of the slab 2.

[0086] Preferably, the two inclined surfaces 611, 621 respectively comprise a plurality of backing teeth suitable for maintaining the two wedge-shaped elements 61, 62 in mutual position.

[0087] According to a further preferred embodiment, the adj ustment/blocking device 7 comprises:

- an engagement element 75 comprising a planar surface 750 which engages the first slab face 21 and a backing surface 751;

- an adjustment member 70 comprising a thrust head 71 which engages the backing surface 751 and an adjustment shank 72 suitable for adjusting the relative position of the thrust head 71 performing a thrust action on the wedge-shaped element 75.

[0088] Preferably, the adjustment member 70 is suitable for performing, by means of the thrust head 71, a thrust action on the engagement element 75.

[0089] Preferably, the adjustment member 70 is adjustable by rotating the adjustment shank 72, for example using a specific tool, screwdriver or wrench.

[0090] Furthermore, according to a preferred embodiment, the adj ustment/blocking group 4 also comprises a supporting foot 9 suitable for protecting the slab foot 23 in the engagement thereof with the supporting device 3. Preferably, said supporting foot 9 has a "U" shaped section and defines a recess housing the slab foot 23.

[0091] According to a preferred embodiment, as shown by way of example in Figure 21, the supporting foot 9 comprises a convex lower portion 91 having a lower surface 911, positioned in contact with an inner surface 302 of a concave upper portion 301 of the base 30 of the supporting device 3. The lower portion 91 of the supporting foot 9 slides with respect to the base 30 in a transverse direction, so as to favor the oscillation of the slab 2 around the longitudinal axis X-X.

[0092] In a preferred embodiment, the supporting foot 9 is made of polymeric material, for example polyamide (PA) , for example polyamide 6 (PA6) , or polypropylene (PP) , or polyoxymethylene (POM) .

[0093] Innovatively, the balustrade assembly described above largely fulfills the object of the present invention, overcoming the typical problems of the prior art .

[0094] Advantageously, in fact, the balustrade assembly allows a safe engagement between a slab made of glass and the relative supporting device.

[0095] Advantageously, the balustrade assembly allows a simple adjustment which ensures the certainty of the proper engagement.

[0096] Advantageously, the blocking device allows for simple safe assembly of the balustrade assembly.

[0097] Advantageously, the balustrade assembly ensures a simple structure and a reduced number of components which allow quick and intuitive assembly.

[0098] Advantageously, the blocking device guarantees the balustrade assembly excellent compactness, also improving the design of the balustrade assembly.

[0099] It is clear that those skilled in the art may make changes to the balustrade assembly described above in order to meet incidental needs, all falling within the scope of protection defined in the following claims.

Claims

1. A balustrade assembly (1) comprising: i) a slab (2) , made of glass, which extends planarly comprising a first slab face (21) and a second slab face (22) , and a slab foot (23) ; ii) a supporting device (3) comprising a base (30) , a first wing (31) , and a second wing (32) , which extend from said base (30) identifying a cavity (300) therebetween in which the slab foot (23) is insertable; iii) an adj ustment/blocking group (4) suitable for blocking the slab (2) in the supporting device (3) , wherein the ad usting/blocking group (4) comprises at least one adj ustment/blocking device (5, 6, 7) housed in said cavity (300) between the first slab face (21) and the first wing (31) ; wherein the supporting device (3) comprises a thrust fin (320) in the second wing (32) positioned in a region opposite to the adj ustment/blocking group (4) , wherein said thrust fin (320) is positionable in a preferably angled position suitable for recovering the inclination of the slab ( 2 ) .

2. Balustrade assembly (1) according to claim 1, wherein the supporting device (3) is a component made in one piece, preferably obtained by extrusion, which extends along a longitudinal axis (X-X) , so that the thrust fin (320) is an integral part of the second wing (32) .

3. Balustrade assembly (1) according to claim 1, wherein the thrust fin (320) is removably mountable, preferably in an appropriate cavity of the second wing (32) .

4. Balustrade assembly (1) according to claim 2 or claim 3, wherein the thrust fin (320) extends over the entire longitudinal axis (X-X) .

5. Balustrade assembly (1) according to claim 2 or claim 3, wherein the thrust fin (320) comprises a plurality of thrust segments aligned along the longitudinal axis (X- X) .

6. Balustrade assembly (1) according to any one of the preceding claims, wherein the thrust fin (320) in an unbiased, starting position is positioned, preferably protruding, towards the interior of the cavity (300) .

7. Balustrade assembly (1) according to any one of the preceding claims, wherein the second wing (32) comprises a thrust compartment (325) positioned in an opposite region with respect to the cavity (300) , wherein the thrust fin (320) in the angled configuration is housed in said thrust compartment (325) .

8. Balustrade assembly (1) according to any one of the preceding claims, comprises an elastically yielding backing element (8) , engaged with the thrust fin (320) , suitable for coming into contact with the slab (2) .

9. Balustrade assembly (1) according to claim 8 in combination with claim 7, wherein the backing element (8) is shaped to embrace the upper end of the thrust fin (320) being housed with a first portion (81) in the cavity (300) and with a second portion (82) in the thrust compartment (325) .

10. Balustrade assembly (1) according to claim 9, wherein the backing element (8) is elastically yielding so that the second portion housed in the thrust compartment (325) allows angling the thrust fin (320) while avoiding its buckling .

11. Balustrade assembly (1) according to any one of claims 1 to 10, wherein the adj ustment/blocking device (5) comprises:

- a pair of gibs (51, 52) , wherein each gib (51, 52) comprises an outer surface (511, 521) suitable for being engaged with the supporting device (3) or the slab (2) , respectively, and an inner surface (512, 522) comprising a housing (510, 520) delimited at the top by an inclined wall (510' , 510") ;

- a control member (53) comprising an upper block (531) , a lower block (532) , and at least one screw element (535) engaged with the upper block (531) and the lower block (532) ; wherein upon the rotation of the at least one screw element (535) , the upper block (531) and the lower block

(532) are moved either away from or towards each other while the two gibs are moved either away from or towards each other.

12. Balustrade assembly (1) according to any one of claims 1 to 10, wherein the adj ustment/blocking device

(6) comprises:

- a first wedge-shaped element (61) comprising a planar surface (610) which engages the first slab face (21) , and an inclined surface (611) opposite to the planar surface;

- a second wedge-shaped element (62) comprising a planar surface (620) which engages the first wing (31) , and an inclined surface (621) opposite to the planar surface; wherein the first wedge-shaped element (61) and the second wedge-shaped element (62) are mutually engaged by means of the two inclined walls (611, 621) ; wherein the two inclined surfaces (611, 621) comprise a plurality of backing teeth, respectively.

13. Balustrade assembly (1) according to any one of claims 1 to 10, wherein the ad ustment/blocking device

(7) comprises:

- an engagement element (75) comprising a planar surface

(750) which engages the first slab face (21) and a backing surface (751) ; an adjustment member (70) comprising a thrust head (71) which engages the backing surface (751) and an adjustment shank (72) suitable for adjusting the relative position of the thrust head (71) performing a thrust action on the wedge-shaped element (75) . 14. Balustrade assembly (1) according to any one of the preceding claims, comprising a plurality of longitudinally aligned slabs (2) .

15. Balustrade assembly (1) according to any one of the preceding claims, wherein the adj ustment/blocking group (4) comprises a supporting foot (9) suitable for protecting the slab foot (23) in the engagement thereof with the supporting device (3) .

16. Balustrade assembly (1) according to any one of the preceding claims, wherein the blocking/adj ustment group (4) comprises a plurality of blocking/adj ustment devices

(5, 6, 7) arranged longitudinally spaced apart along the supporting device (3) .