EP1286018B1 - Roller blind with predetermined course of roller angular velocity - Google Patents

Abstract

The roller blind (3) consists of a foil with horizontal reinforcing ribs (5) at regular intervals. Each rib defines space sharp 90 degrees bend in the foil, and the section in between is gently curved. There is a bar (4) at the bottom of the foil. The foil is wound up on a roller (2) which is shaped as an isosceles triangle. The roller shaft (1) is driven by a motor (M) driving through a reduction gear (R) with non-circular gear wheels (1-6).

Description

The invention relates to a roller blind with a roller blind film according to the type specified in the preamble of claim 1.

Roller blinds with roll-up covers for windows on buildings or other openings are available in various embodiments, e.g. in the form of a roller shutter or a roller shutter known. In the basic form for vertical installation position, the roller blind consists of an upper winding shaft for winding a Rollbehanges on the winding shaft and for unwinding from the winding shaft to a film surface, wherein the free-hanging end is weighted by an end bar.

In a special embodiment, the Rollbehang consists of a thin, foil-like roller blind film, which has parallel to the winding shaft creases. The EP 950,801 describes such a blind. These creases form a wave profile in the unwound film surface and a triangular profile in the wound film roll. Further embossed Rollbehänge are from EP 0 737 795 . DE 3 045 883 . US 3,195,616 and US 5,671,387 known.

A wave profile is advantageous on the one hand, for example because it makes the film surface decorative, on the other hand it is problematic because it elastically springs in tension in the longitudinal direction. As a result, in the free-hanging, weighted with the end bar foil surface during winding and unwinding significant vibrations occur that affect the appearance of the roller blinds and can also lead to disturbances in the function.

The invention is based on the object a roller blind specified in the preamble of claim 1 type such that, while avoiding the disadvantages mentioned a uniform winding and unwinding is guaranteed.

This object is achieved by the characterizing features of claim 1 in conjunction with its preamble features.

Further solutions and embodiments of the invention form the subject of the dependent claims.

The vibrations occurring during winding and unwinding of roller blind films, in particular with creases and the resulting wave profile, can be explained by the interaction of the following properties of the roller blind considered here. The elastic foil surface forms, together with the end bar arranged below, a spring-mass system whose resonance frequency varies with the length of the freely suspended part. If the film roll has a profile, for example a triangular profile, during spinning periodically increasing and decreasing tensile forces on the film surface transfer. These excite in agreement with the resonance frequency to vibrations.

According to the invention, control means are therefore connected upstream of the winding shaft to solve this dynamic problem, which change the rotational speed of the winding shaft so that the winding shaft per revolution has several periods with a predetermined angular velocity. As a result, the possibly resulting on the winding shaft or existing non-round shapes are compensated. As a result, even with a film winding with a non-circular profile when winding and unwinding no swelling and declining tensile forces. The film surface moves evenly, vibration-free up or down.

The Rollo foil with creases can be made of plastic, metal or other resilient material.

A plastic roller blind is e.g. made of polyester with a thickness of 0.01 to 0.15 mm. In one embodiment, the creases are arranged parallel to the take-up shaft, depending on the thickness at a distance of 7 to 40 mm, and the bending angle is 120 to 180 degrees in the direction of rotation of the film roll.

A corresponding roller blind made of metal consists for example of stainless spring steel with a thickness of 0.005 to 0.100 mm. The distance between the creases is, depending on the thickness and elastic modulus, about 7 to 100 mm.

In particular, the problem mentioned at the beginning occurs when the roller blind foil is provided with creases which forms a wave profile in the foil surface and a triangular profile on the winding shaft. The foil wrap in the triangular profile has approximately the shape of an equilateral triangle with rounded corners.

The decisive for the linear movement of the film surface effective winding radius varies accordingly between the corner and the side belonging to the maximum and minimum radius. To compensate for this non-round profile, the control means vary the angular velocity inversely proportional to the effective winding radius, so that at the transition to the film surface, the tangential velocity remains constant. In this respect, the winding shaft on three periods, each with an angular velocity curve. According to the present geometry, the ratio between minimum and maximum angular velocity is about 0.5 to 0.75.

The control means may in principle be designed electronically or mechanically.

In a purely mechanical embodiment, the control means between the winding shaft and the drive shaft are arranged. In this case, a transmission forms the control means by having at least one control curve over which the periods are determined by the angular velocity profile. In a profile triangular foil winding the control curve is provided with three curve sections, so that the winding shaft with three periods each provided with an angular velocity profile.

The film winding can also be quadrangular or pentagonal, for example, wherein the transmission accordingly has cams in four or five periods.

The transmission can be designed differently. The following embodiments will be explained using the example of a triangular film roll.

On the one hand, the transmission is designed as a drive belt drive with pulleys circulating drive belt. The variation of the angular velocity is achieved by a similar to the film winding triangular profile, connected to the winding shaft pulley. The control cam is thus arranged on the pulley.

On the other hand, the control means may be formed as a toothed belt drive with toothed belts rotating about gears, wherein the gear wheel connected to the winding shaft has a triangular profile. The control cam is thus arranged on the gear. The second, connected to the drive shaft gear preferably also has a control cam, such as a triangular, ellipse or eccentric. It goes without saying that the exact shape of this cam having the control cam is designed so that the toothed belt remains evenly stretched over the revolutions.

Furthermore, the transmission can be considered a gear transmission with eccentric, elliptical or triangular gears be formed, wherein the gear shaft connected to the winding shaft is triangular. The control cam is thus on the gear. When combining a triangular and an elliptical gear, the reduction ratio is 3: 2, and for a triangular with an elliptical gear, it is 3: 1.

In a special variant, several triangular gears are arranged in a row. In this way, if necessary, a large distance between the winding shaft and drive shaft can be bridged. The gear connected to the drive shaft may also be elliptical or eccentric, such as to achieve a reduction of 3: 2 or 3: 1.

The transmission may also include one or two universal joints. It is exploited that universal joints, whose waves bend at an angle, the angular velocity vary twice per one sine function per revolution. Since three periods per revolution are needed to compensate for the triangular film roll with a roller blind film with creases, a transmission with a reduction ratio of 3: 2 is arranged between the universal joint and the winding shaft.

In an electronic version, the drive shaft is coupled directly to the winding shaft. In this case, forms an electronic speed control of the roller blind drive the control means by this determines the angular velocity over the periods.

As a result, changes the drive shaft in three periods per revolution, the angular velocity, for example, if the roller blind film has creases and the film winding is triangular in profile. Suitable electronic speed controllers, which also include sensors for measuring angles of rotation and speeds, are known to the person skilled in the art.

In a variant of this, the basic speed is switchable in two or more speed levels. The electronic speed control is switchable in at least two speed profiles per revolution. With a signal generator for switching between the velocity profiles, the switching signal is generated for a certain length of the unwound film surface. In this way, the resonance case, which indeed varies with the length of the unwinding or winding film surface, can be skipped by changing the basic speed.

Fig. 1

eine schematische Darstellung eines Rollos gemäß einer ersten Ausführungsform der Erfindung von der Frontseite;

Fig. 2

eine Seitenschnittansicht des Rollos von Fig.1 mit Folien-Wickel und Folien-Fläche;

Fig. 3

eine schematische Ansicht eines Treibriemengetriebes gemäß einer weiteren Ausführungsform der Erfindung;

Fig. 4

eine schematische Ansicht eines Zahnriemengetriebes gemäß einer weiteren Ausführungsform der Erfindung;

Fig. 5

eine schematische Ansicht eines Zahnradgetriebes gemäß einer weiteren Ausführungsform der Erfindung, und

Fig. 6

eine schematische Ansicht eines Getriebes mit Kreuzgelenken gemäß einer weiteren Ausführungsform der Erfindung.

Further advantages and features will become apparent from the following description of several embodiments of the invention in conjunction with the drawings. Show it:

Fig. 1

a schematic representation of a roller blind according to a first embodiment of the invention from the front side;

Fig. 2

a side sectional view of the roller blind of Figure 1 with film winding and film surface;

Fig. 3

a schematic view of a belt drive according to another embodiment of the invention;

Fig. 4

a schematic view of a toothed belt transmission according to another embodiment of the invention;

Fig. 5

a schematic view of a gear transmission according to another embodiment of the invention, and

Fig. 6

a schematic view of a transmission with universal joints according to another embodiment of the invention.

In Fig. 1, a roller blind is shown with a winding shaft 1 for winding a roller blind foil to a film winding 2 and for unwinding to a film surface 3, at the movable end of an end bar 4 is arranged.

In the roller blind foil creases 5 are introduced, which extend parallel to the winding shaft 1. A roller blind drive M is formed by an electric motor whose drive shaft 6 acts on the winding shaft 1 via a gear R. The transmission R is interposed between the drive shaft 6 and the winding shaft 1 and formed in the embodiment shown here as a gear transmission. This gear transmission will be explained below with reference to FIG. 5 in more detail.

In Fig. 2, the blind of Fig. 1 is shown in the side cross-section. Due to the crease embossments 5, the roller blind foil winds to a film winding 2 with triangular profile, and the freely hanging film surface 3 forms a wave profile. The film surface 3 elastically springs in the longitudinal direction due to the wave profile and forms together with the end bar 4 a vibratory spring-mass system. As the film roll 2 turns, the triangular profile causes periodically varying tensile forces, which lead to vibrations in the case of resonance.

In Fig. 3, the transmission is shown as a belt transmission with circulating belt T0. The driving pulley T1 is circular, and the pulley T2 coupled to the winding shaft 1 has a control cam in the form of a triangular profile, which is approximately similar to that of the film winding. This achieves a changing angular velocity in three periods per revolution.

4, the transmission is shown in the form of a toothed belt transmission with circulating toothed belt R0. The two gears R1 and R2 are designed in this embodiment with a control cam as a triangular profile, although only the coupled to the winding shaft 1 gear R2 must be triangular. The other driving toothed disc R1 can also be designed eccentrically or elliptically, for example in order to achieve a reduction ratio of 3: 1 or 3: 2.

Fig. 5 shows a further transmission in the form of a gear transmission with arranged in a row gears Z1, Z2 and Z3. The coupled to the drive shaft 6 Gear Z1 is provided with a cam, which is designed elliptical in this embodiment, so that at the same time a reduction of 3: 2 is achieved in addition to the changing angular velocity. The series shown with three gears Z1, Z2 and Z3 can of course be extended by further each having a triangular cam having gears, as to bridge a large distance between the drive shaft 6 and winding shaft 1.

The calculation and production of such a control cam having gears are known in the art in principle.

Fig. 6 shows a further embodiment of a transmission with universal joints X1 and X2 for generating a changing angular velocity. As this embodiment shows, the shaft 7 is arranged at a certain angle to the drive shaft 6, whereby at both universal joints X1 and X2, the angular velocity varies in a sine curve twice per revolution.

Since three periods with an angular velocity profile per revolution are needed to compensate for the foil coil with creases and the resulting triangular profile, a gear transmission G with a reduction ratio of 3: 2 is connected downstream.

List of reference numbers

1

winding shaft

2

Wrapping

3

Foil surface

4

end bar

5

kink embossing

6

drive shaft

R0

toothed belt

R1, R2

gear

T0

belts

T1, T2

pulley

Z1, Z2, Z3

gear

X1, X2

Universal joint

G

Transmission 3: 2

R

control means

M

Roller blind drive, electric motor

Claims (14)

1. A blind comprising a blind film, comprising a rotatable winding shaft (1) for winding the blind film onto said winding shaft (1) to form a film reel (2) and for unwinding the blind film from this winding shaft (1) to form a film surface (3) and comprising a blind drive (M), characterised in that control means (R) are located ahead of the winding shaft (1), which control means vary the rotational speed of the winding shaft such that the winding shaft (1) has several periods with a predetermined angular velocity profile per revolution.
2. The blind according to claim 1, characterised in that the blind film is provided with kink embossing patterns (5) which form a corrugated profile in the film surface (3) and form a triangular profile on the winding shaft (1).
3. The blind according to claim 2, characterised in that the blind film consists of polyester with a thickness of 0.01 to 0.150 mm and the distance between the kink embossed patterns (5) is 7 to 40 mm.
4. The blind according to claim 2, characterised in that the blind film is made of metal having a thickness of 0.005 to 0.100 mm and the distance between the kink embossed patterns (5) is 7 to 100 mm.
5. The blind according to any one of claims 2 to 4, characterised in that the control means (R) have three periods each having a winding speed profile of the winding shaft (1) during winding and unwinding.
6. The blind according to any one of the preceding claims, characterised in that the winding speed profile is the same in each period.
7. A blind with gearing interposed between the winding shaft (1) and the blind drive (M) according to claim 1, characterised in that the gearing forms the control means (R) having at least one control cam by which means the periods with the angular velocity profile are fixed.
8. The blind according to any one of claims 2 to 7, characterised in that the gearing (R) is configured as driving belt gearing and the control cam is arranged on a pulley (T2).
9. The blind according to any one of claims 2 to 7, characterised in that the gearing (R) is configured as a toothed belt gearing and the control cam is arranged on at least one toothed wheel (R1, R2).
10. The blind according to any one of claims 2 to 7, characterised in that the gearing (R) is configured as a toothed wheel gearing and the control cam is arranged on at least one toothed wheel (Z1, Z2, Z3).
11. The blind according to claim 10, characterised in that the toothed wheel gearing comprises three or more toothed wheels (Z1, Z2, Z3) with control cams, wherein the first toothed wheel (Z1) coupled to the drive shaft (6) is configured as triangular, elliptical or eccentric and the second (Z2) and other toothed wheels (Z3) are all configured as substantially triangular.
12. The blind according to any one of claims 2 to 11, characterised in that the gearing (R) comprises one or more universal joints (X1, X2) with shafts (6, 7) kinking at predetermined angles.
13. The blind according to any one of the preceding claims, characterised in that the control means (R) are formed by an electric motor (M) with electronic speed control.
14. The blind according to claim 13, characterised in that the electronic speed control can be switched over to at least two speed profiles per revolution and is provided with a signal transducer for switching over between the speed profiles, wherein the signal transducer generates the switchover signal at a certain length of the unwound film surface.

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