EP2857627B1

EP2857627B1 - Roller shutter slat and method of producing a roller shutter slat

Info

Publication number: EP2857627B1
Application number: EP13187242.6A
Authority: EP
Inventors: Federico Karagulian; Werner Baumann
Original assignee: Regazzi SA
Current assignee: Regazzi SA
Priority date: 2013-10-03
Filing date: 2013-10-03
Publication date: 2016-11-30
Anticipated expiration: 2033-10-03
Also published as: EP2857627A1

Description

The invention relates to a roller shutter slat according to the preamble of claim 1. Furthermore, the invention relates to a method for producing a roller shutter slat.

Background of the invention

Roller shutters for solar protection of a building often comprise a plurality of vertically moveable slats in order to lower them down into a closed position or to lift them up into an open position. The lowering and lifting action can be performed manually or automatically. Commonly known are roller shutter slats made from a coated aluminum strip roll-formed into a hollow body profile having a male upper end and a female lower end for engagement with other slats when lowered down into the closed position. The engagement of the slats prevents intrusion of surface water, in particular when the upper end of each slat has a male, i.e. convex formed, configuration and the lower end has a correspondingly female, i.e. concave formed, configuration.
When the roller shutter is lowered down, the slats contact each other thereby regularly producing, due to the material and the hollow body profile of each slat, an annoying noise. In order to reduce the noise it is known to fill the hollow body profile of each slat with an insulating material. Using an insulating material for filling the hollow body profile of the slats has the additional effect that the shutter provides a thermal insulation when closed.
EP 0 365 908 A1 discloses a roller shutter slat made of an aluminum strip roll-formed into a hollow body profile having a hooked and a G-shaped connecting end. For use in a soundproof shutter the slat has a plastic coating extruded or laminated on the inner face of the hollow body profile such that a double-layer plastic coating is formed in the area of the connecting ends for mutual sound isolation. In addition, the hollow body profile may be filled with a plastic foam material.
Roller shutter slats having a hollow body profile are also known from DE 198 51 934 A1 . Before roll-forming the aluminum strip is laminated with a plastic foil in order to increase wear-resistance.
DE 94 06 034 U1 discloses a roller shutter gate consisting of a plurality of hollow metal panels hinged to one another. In order to reduce wear in the area of the joint, it is proposed to insert a profiled gasket.
FR 1 530 680 A discloses a roller shutter consisting of a plurality of slats having a hollow body profile, whereby upper ends and lower ends are adapted to form a joint with the respective ends of the hollow body profile of an adjacent slat. The upper end of each hollow body profile comprises a ridge having two mechanical stops in order to reduce friction.
EP 0 678 647 A1 relates to roller blinds, constituted by slats, hinged to one another by hook-shaped edges engaging with G-shaped edges. In order to prevent relative movement between the slats in longitudinal direction the hook-shaped edges are provided with anchoring elements engaging in a snap-together manner with an opening provided in the adjacent slat. DE 338 382 C also relates to the problem of lateral movement between two adjacent slats of a roller shutter device and suggests to provide the upper end of each slat with a flexible tongue engaging with a mechanical stop on the outside of the adjacent slat.
For the production of roller shutter slats it is well known to use coated aluminum strips. The coating is applied on the aluminum strip before it is roll-formed. In general the function of the coating is to improve the appearance and/or to increase the wear resistance of the slat made thereof. Thus the coating is applied to the side of the aluminum strip forming the later outside of the hollow body profile. For this purpose, very often coatings are used, that are prone to trap water in humid environments. Furthermore, it is common to use water-based coatings. Unfortunately, roller shutter slats made of such coated aluminum strips, in use, tend to stick together when exposed to high temperatures, e.g. temperatures of 35°C and more. As a consequence, during lifting the shutter the slats at first stick together and than drop with a loud noise.
It is an object of the present invention to improve a roller shutter slat roll-formed from a coated aluminum strip so that it does not tend to stick to an adjacent slat when exposed to high temperatures.
This object is achieved by a roller shutter slat according to claim 1. Preferred embodiments of the invention are specified in the depending claims. This object is further achieved by a method for producing a roller shutter slat according to claim 7.

Summary of the invention

Proposed is a roller shutter slat roll-formed from a coated aluminum strip to a hollow body profile having a male upper end and a female lower end for engagement with one or more other slats. According to the invention, the male upper end is provided in longitudinal direction with at least two spacing elements projecting from the outline of the male upper end. The projecting spacing elements prevent the male upper end from contacting the female lower end of an adjacent slat over its entire longitudinal extension. Thus, the area of contact is reduced to the exterior surfaces of the spacing elements. By reducing the area of contact two adjacent slats tend less to stick together when exposed to high temperatures.
It is commonly known to bend a slat in longitudinal direction in order to reduce the area of contact with an adjacent slat. However, the bending of a slat makes its production difficult and thus, produces higher costs. In contrast, it is less labor-intensive and/or less cost-intensive to provide the male upper end of a slat with at least two spacing elements according to the invention.
Preferably, at least one spacing element is located near an end section of the roller shutter slat with regard to its longitudinal extension. More preferably, each end section of the slat comprises at least one spacing element to ensure that the area of contact is reduced to the exterior surfaces of the spacing elements. Depending on the length of the slat, a plurality of spacing elements can be evenly distributed in longitudinal direction in order to spread the load of subsequent slats.
Advantageously, the spacing elements are made from the coated aluminum strip of the hollow body profile by punching and bending the profile. Such spacing elements are easily produced by metal forming and low in costs.
According to the invention, each spacing element comprises at least one nose projecting from the outline of the male upper end next to an opening of the hollow body profile. The position next to an opening facilitates the manufacture of the nose, for example by punching and bending the coated aluminum strip of the hollow body profile. In this case, at first an opening is created by punching the coated aluminum strip in the area of the male upper end. Then an edge of the opening is at least partly bent outward to form a nose projecting from the convex curved outline of the male upper end. Thereby, the opening is enlarged. Preferably, the opening has the form of a slot in order to receive a belt, a cord or a strap for linking a plurality of slats. Provided that the edge of the opening is only partly bent, i. e. not over its entire length, the opening has a larger longitudinal extension than the nose next to it. In this case the nose may be arranged centrally or off-center with regard to the longitudinal extension of the opening. Besides, by partly bending the edge also a plurality of noses can be formed next to the opening. For example, two noses can be provided at each end of the opening.
Preferably, each spacing element comprises a pair of noses projecting from the outline of the male upper end and flanking a centrally arranged opening or a plurality of openings of the hollow body profile lying within a sectional plane. A spacing element having a pair of noses ensures that the area of contact is reduced to the exterior surfaces of the two noses even when the slats are tilted. Besides, a pair of noses allows for a better load spreading. For example, when lowering down a roller shutter ans subsequent slats exert an impact on a slat beneath. The impact is more evenly distributed by two noses than by only one nose. Preferably, the two noses are symmetrically arranged on both sides of the male upper end when looking at the cross-section of the slat.
According to the first alternative mentioned, the two noses flank a centrally arranged opening of the male upper end with regard to its cross-section. This arrangement facilitates the manufacture of the noses since only one opening has to be created. In order to form the pair of noses two opposite edges of the opening are at least partly bent. The opening preferably has the form of a longitudinal slot for receiving a belt, a cord or a strap in order to link a plurality of slats. Further preferably, also the female lower end of the slat has a centrally arranged opening for feeding the belt, cord or strap through the hollow body profile of the slat.
According to the second alternative mentioned, the two noses flank a plurality of openings of the male upper end, preferably two openings, lying within a sectional plane. In this case, each nose is located next to an opening arranged off-center with regard to the cross section of the hollow body profile. These openings may also serve to receive a belt, a cord or a strap in order to link a plurality of slats. Preferably, the female lower end of the slat has corresponding openings.
According to a further preferred embodiment of the invention, the hollow body profile is filled with a thermal and/or acoustic insulation material, preferably with plastic foam material, most preferably with polyurethane. The insulation material inside the hollow body profile prevents the formation of a thermal bridge and absorbs sound.
Further proposed is a roller shutter for solar protection comprising at least two slats according to the invention. The slats are vertically movable such, that in a closed position a male upper end of a first slat engages with a female lower end of a second slat. The spacing elements provided reduce the area of contact between the male upper end of the first slat and the female lower end of the second slat, thereby preventing the slats from sticking together when exposed to high temperatures. Due to the spacing elements, there is no sudden detachment and dropping of the slats when lifted which creates an annoying noise. Thus, the roller shutter proposed allows for quiet operation.
In addition, a method for producing a roller shutter slat from a coated aluminum strip is proposed, comprising the steps

roll-forming the coated aluminum strip to a hollow body profile having a male upper end and a female lower end,
punching the male upper end in order to create an opening and
at least partly bending an edge of the opening in order to form a nose projecting from the outline of the male upper end of the slat.

The slat produced by the method proposed comprises at least one nose projecting from the outline of the male upper end of the hollow body profile. The nose serves as an spacing element, which reduces the area of contact between the male upper end of the slat and a female lower end of an adjacent slat linked together to form a roller shutter. The reduced area of contact prevents the slats from sticking together when exposed to high temperatures.
The creation of the spacing element by the proposed punching and bending processes is easily performed and can be implemented in the current production process of a roller shutter slat without changing the production time. The punching process may be necessary to create an opening for receiving a belt, a cord or a strap. In this case, only the bending process has to be implemented in the current production process. Punching and bending can be performed at the same time and/or with the same tool, for example by means of a punching press. Preferably, the punching press comprises a cutting tool that cuts and bends the coated aluminum strip roll-formed to a hollow body profile while penetrating it. The opening is enlarged by the bending process.
According to a preferred embodiment of the invention, the coated aluminum strip is punched in a central region of the male upper end with regard to its cross-section to create a centrally arranged opening and two opposite edges of the opening are at least partly bent in order to form a pair of noses projecting from the outline of the male upper end flanking the opening. The slat produced by this method comprises at least one pair of projecting noses serving as a spacing element, which reduces the area of contact between the male upper end of the slat and the female lower end of an adjacent slat linked together to form a roller shutter. The reduced area of contact prevents the slats from sticking together when exposed to high temperatures. Besides, the pair of noses ensures an even load distribution on the slat.
As an optional step the method according to the invention may comprise the step of filling the hollow body profile with a thermal and/or acoustic material, preferably with plastic foam, most preferably with polyurethane. The optional step of filling the hollow body profile with an insulating material may comprise a further step of heating, in particular when plastic foam is used as insulating material. Preferably, the slat is heated up to a temperature of 30 to 50°C, most preferably 35 to 45°C, in order to liquefy the plastic foam material for injection. After injection, the plastic foam material undergoes an exothermic process and expands inside the hollow body profile until the hollow space is completely filled with plastic foam.
Preferably, the hollow body profile is filled with a thermal and/or acoustic material before punching and bending the roller shutter slat in order to prevent leaking.
When the insulating material inside has set - provided that the hollow body profile has been filled with such material - the roller shutter slat may be cut to a certain length. The slat may be cut before or after the steps of punching and bending in order to create the spacing elements.
Preferred embodiments of a roller shutter slat according to the present invention will be described in more detail hereafter. The description refers to the accompanying drawings. In the drawings:

Fig. 1a is a side elevation of an end section of a slat according to a first preferred embodiment of the invention,
Fig. 1b is a cross section of the slat of fig. 1a,
Fig. 2a is a side elevation of an end section of a slat according to a second preferred embodiment of the invention,
Fig. 2b is a cross section of the slat of fig. 2a,
Fig. 3a is a side elevation of an end section of a slat according to a third preferred embodiment of the invention,
Fig. 3b is a cross section of the slat of fig. 3a.
Fig. 4a is a side elevation of both end sections of a slat according to a forth preferred embodiment of the invention and
Fig. 4b is a cross section of the slat of fig. 4a.

Detailed description of the drawings

As shown in the figures, a slat 1 according to the invention has a hollow body profile with a male upper end 2 and a female lower end 3. The male upper end 2 has a convex shape, whereas the female lower end 3 has a concave shape. Both ends 2, 3 are adapted to engage with correspondingly shaped ends of adjacent slats linked together to form a vertically moveable roller shutter. By engagement, the male upper end 2 of first slat 1 contacts the female lower end 3 of second slat 1.
The hollow body profile is made from a coated aluminum strip by roll-forming. Usually, the coating is a water-based coating deposited on the side of the aluminum strip becoming the outside of the hollow body profile. Due to the coating, conventional roller shutter slats tend to stick together when exposed to high temperatures, e.g. temperatures of 35°C and more. This problem is solved by a roller shutter comprising a plurality of slats 1 according to the present invention.
A slat 1 according to the present invention is provided in longitudinal direction with at least two spacing elements 4 projecting from the outline of the male upper end 2 of the hollow body profile. The spacing elements 4 reduce the area of contact between the male upper end 2 of a first slat 1 with a female lower end 3 of a second slat 1 to the exterior surfaces of the spacing elements 4. Thus, there is no planar or linear contact between the two slats 1 over their entire length.
The slats 1 shown in figures 1a to 4b are provided with spacing elements 4, of which each spacing element 4 comprises at least one pair of noses 5 projecting from the outline of the male upper end 2 of the hollow body profile. The noses 5 have been created by punching and bending the coated aluminum strip roll-formed to a hollow body profile. Thus, each nose 5 is located next to an opening 6. The opening 6 may serve to receive a belt, a cord or a strap for linking the slat 1 with a plurality of other slats 1.
Fig. 1a and 1b show a first preferred embodiment of a slat 1 according to the present invention. As can be seen in fig. 1a, the spacing element 4 is located near an end section a of the slat 1 with regard to its longitudinal extension. The spacing element 4 comprises two pairs of noses 5 each pair flanking a centrally arranged opening 6 with regard to the cross-section of the slat 1 (see fig. 1b). The opening 6 has the form of a slot. Both ends of the slot are provided with a pair of noses 5 having a smaller longitudinal extension than the opening 6 (see fig. 1a). Two noses 5 flanking the opening 6 and forming a pair of noses 5 are lying in a sectional plane 7 (see fig. 1a), i. e. on both sides of the hollow body profile when looking at the cross-section (see fig. 1b). As can be seen in fig. 1b, the hollow body profile of the slat 1 is filled with a thermal and acoustic insulation material 8.
Fig. 2a and 2b show a second preferred embodiment of a slat 1 according to the present invention. It differs from the embodiment shown in fig. 1a and 1b in that the male upper end 2 has no centrally arranged opening 6 but two openings 6 on opposite sides of the hollow body profile (see fig. 2b). The openings 6 are located near an end section b of the slat 1 with regard to its longitudinal extension (see fig. 2a). Each opening 6 is provided at both ends with a nose 5 which forms a pair of noses 5 with a corresponding nose 5 on the opposite side of the hollow body profile.
Fig. 3a and 3b show a third preferred embodiment of a slat 1 according to the present invention. It differs from the embodiments shown in fig. 1a to 2b in that the spacing element 4 located near an end section b of the slat 1 with regard to its longitudinal extension comprises only one pair of noses 5 flanking an opening 6 (see fig. 3b). The pair of noses 5 is arranged centrally with regard to the longitudinal extension of the opening 6 (see fig. 3a). Each nose is cut free on three sides (see fig. 3a), which facilitates bending of the material in order to form the noses 5.
Fig. 4a and 4b show a forth preferred embodiment of a slat 1 according to the present invention. In fig. 4a, both end sections a, b of slat 1 are shown. Each end section a, b is provided with a spacing element 4 projecting from the outline of the male upper end 2 of the hollow body profile comprising two pairs of noses 5 flanking an opening 6 (see fig. 4b). Each nose is cut free on two sides (see fig. 4a), which facilitates bending of the material in order to form the noses 5.
All figures show examples of preferred embodiments of the invention. Modifications and/or combinations of features are possible and fall within the scope of invention, as defined by the appended claims. Modifications may relate to the shape of the hollow body profile, its male upper end 2 and/or its female lower end 3. They may further relate to the number, shape or location of the noses 5 and/or the openings 6.

Reference list

1: slat
2: male upper end
3: female lower end
4: spacing element
5: nose
6: opening
7: sectional plane
8: thermal and/or acoustic insulation material

Claims

Roller shutter slat (1) roll-formed from a coated aluminum strip to a hollow body profile having a male upper end (2) and a female lower end (3) for engagement with one or more other slats (1),
characterized in that the male upper end (2) is provided in longitudinal direction with at least two spacing elements (4) projecting from the outline of the male upper end (2), the spacing elements (4) preventing the male upper end (2) from contacting the female lower end (3) of an adjacent slat (1) over its entire longitudinal extension, whereby each spacing element (4) comprises at least one nose (5) projecting from the outline of the male upper end (2) next to an opening (6) of the hollow body profile.
Roller shutter slat according to claim 1,
characterized in that at least one spacing element (4) is located near an end section (a, b) of the roller shutter slat (1) with regard to its longitudinal extension.
Roller shutter slat according to claim 1 or 2,
characterized in that the spacing elements (4) are made from the coated aluminum strip of the hollow body profile by punching and bending the profile.
Roller shutter slat according to one of the preceding claims,
characterized in that each spacing element (4) comprises a pair of noses (5) projecting from the outline of the male upper end (2) and flanking a centrally arranged opening (6) or a plurality of openings (6) of the hollow body pofile lying within a sectional plane (7).
Roller shutter slat according to one of the preceding claims,
characterized in that the hollow body profile is filled with a thermal and/or acoustic insulation material (8), preferably with plastic foam material, most preferably with polyurethane.
Roller shutter for solar protection comprising at least two slats (1) according to one of the preceding claims, wherein the slats are vertically movable such, that in a closed position a male upper end (2) of a first slat (1) engages with a female lower end (3) of a second slat (1).
Method for producing a roller shutter slat (1) from a coated aluminum strip, comprising the steps
- roll-forming the coated aluminum strip to a hollow body profile having a male upper end (2) and a female lower end (3),

- punching the male upper end (2) in order to create an opening (6) and

- at least partly bending an edge of the opening (6) in order to form a nose (5) projecting from the outline of the male upper end (2) of the slat (1),
whereby the nose (5) serves as a spacing element (4) reducing the area of contact between the male upper end (2) of the slat (1) and a female lower end (3) of an adjacent slat (1) when linked together to form a roller shutter.
Method according to claim 7,
characterized in that the coated aluminum strip is punched in a central region of the male upper end (2) with regard to its cross-section to create a centrally arranged opening (6) and two opposite edges of the opening (6) are at least partly bent in order to form a pair of noses (5) projecting from the outline of the male upper end (2) flanking the opening (6).
Method according to claim 7 or 8,
characterized in that the hollow body profile is filled with a thermal and/or acoustic material (8), preferably with plastic foam, most preferably with polyurethane.
Method according to claim 9,
characterized in that the hollow body profile is filled with the thermal and/or acoustic material (8) before punching and bending the roller shutter slat.