Patent Description:
Such zip guides are known from <CIT>. This zip guide comprises a mounting bracket, a guide for the zip of the screen and two side legs mounted on the mounting bracket, on either side of the guide. Each of the side legs comprises a first portion attached to the mounting bracket, disposed substantially perpendicular to the plane of the mounting bracket, and a second portion extending from the first portion at an angle to the first portion so that the second portions of the side legs are directed away from each other.

The side legs of the zip guide are made of an elastic material and can be cast onto the mounting bracket. They therefore provide a resilient effect to absorb the forces acting on the cloth (wind, shrinkage or expansion due to temperature variations, etc.). Moreover, by attaching the side legs to the mounting bracket, one single product is obtained that allows faster and simpler mounting compared to, for example, <CIT>. In the latter document, the zip guide is resiliently arranged with the aid of resilient members to be fitted separately.

A resilient zip guide is also known from <CIT>. The zip guide comprises a mounting bracket, a guide and two positioning lips arranged on either side of the guide. The positioning lips are co-extruded from a softer plastic onto the mounting bracket, which is made from a hard plastic. The positioning lips have a zigzag shape and can have a Z-shaped cross-section, a double Z-shaped cross-section or an S-shaped (wave-shaped) cross-section. In this way a resilient effect is obtained. A problem with such positioning lips, as already stated in <CIT>, is that they are very flexible and during assembly there is a great chance that they will not be positioned in the right place in the side guide, resulting in greater wear. <CIT> solves this problem by manufacturing the positioning lips in a different colour, making it easy to identify incorrect mounting and to correct it.

With wind-resistant blinds (e.g. "screens") it is important that the cloth between the guides is held in place under wind load. Due to varying wind pressures, the cloth has to deal with varying loads that the zip guide has to be able to absorb as well. Furthermore, this cloth must also be kept sufficiently tensioned so that it remains taut in every position. Tolerances on the cloth confection and placement must also be possible to accommodate. Proper spring adjustment of the zip guide is important to meet the above requirements. However, it has been found that under certain circumstances there is an increased friction between the zip and the zip guide, resulting in premature wear of the zip and the zip guide, and unpleasant squeaking noises when the cloth is rolled up and down. In <CIT> this is solved by providing a zone with a lower wear factor in the guide of the zip, via co-extrusion. However, this increases the complexity and the cost of the zip guide. Furthermore, <CIT> is a relevant example of such kind showing the features of the preamble of claim <NUM>.

It is an aim of the present invention to overcome the above-mentioned disadvantages of the prior art. It is, among others, an aim to provide a zip guide that is resiliently mounted to absorb the forces acting on the cloth under all circumstances and that also offers one or more of the following advantages: a simple assembly, a long service life and a limited manufacturing cost.

According to the invention there is therefore provided a zip guide as set out in the appended claims. The zip guide comprises a support which is preferably flat, a guide configured to guide the zip, and a first and a second resilient member arranged on both sides of the guide. The first and the second resilient member each comprise at least three portions, which are preferably slat-shaped and arranged successively from the support onwards and are preferably arranged in a zigzag shape. Thus, the first and the second resilient member each comprise a first portion, a second portion and a third portion, and the resilient members are preferably three-membered. Any two adjacent portions are preferably hingedly attached to each other via a folding rib. For example, a first folding rib is arranged between the first and second portions and a second folding rib is arranged between the second and third portions.

The support preferably has a substantially rectangular cross-section. The support is preferably plate-shaped, with a front side and a rear side. At least one of the front side and the rear side are preferably planar and can define a plane of the support. Preferably, the guide, the first resilient member and the second resilient member are arranged at the front side. Preferably, the first and second resilient members are mirror-symmetrically arranged with respect to a median plane of the zip guide perpendicular to a plane of the support and parallel to the longitudinal direction of the zip guide.

According to a first aspect of the invention, in an idle state of the zip guide, two first adjacent portions are folded towards each other at a first angle. Two second adjacent portions, which are arranged farther from the support than at least one of the two first adjacent portions, are folded towards each other at a second angle. Therefore, the second angle is disposed farther from the support than the first angle. In absolute value the second angle is smaller than the first angle. The first angle and the second angle are preferably located on opposite sides of the corresponding resilient member.

A first portion of the two first adjacent portions is located closer to the support than the other of the two adjacent portions. The two second adjacent portions are formed by a second portion and a third portion. The third portion is arranged farther from the support than the second portion and than the first portion. The second portion can also form the other portion of the two first adjacent portions, so that the second portion is common between the two first adjacent portions and the two second adjacent portions.

The portion adjacent to the support (e.g. the first portion) is advantageously attached to the support in a fixed orientation relative to the support (i.e. not hinged). By way of example, this portion can be cantilevered departing from the support, wherein the portion and (a plane of) the support enclose a (fixed) angle, which is preferably acute. An advantage of such an acute angle is that a direction of deformation of the portion adjacent to the support is well defined under load.

By varying the angles enclosed by the different portions, wherein the enclosed angle becomes smaller with increasing distance from the support, a variable and stepwise increasing resilience with increasing load of the screen cloth on the zip guide is advantageously achieved. By varying the angular magnitudes in such a way, as the load increases, stepwise first the outer portion of the resilient member is excited , followed by the inner parts to an increasing extent. Moreover, by clamping the portion adjacent to the support in a fixed orientation to the support, an even greater variation in the resistance to deformation is advantageously obtained. At smaller loads and deformations, only the outer portions, which can hinge around the folding ribs are excited, so that the resilience advantageously remains limited and the friction between the zip and the guide also remains small. This limits wear and increases service life. Larger loads can then be absorbed by the clamped part, so that even with these larger loads the deformation of the screen cloth remains limited, with less risk of damage. The clamped part also prevents the resilient members from deforming too much and leading to incorrect assembly, as described in <CIT>.

According to a second aspect of the invention, in an idle state of the zip guide, the third portion forms a third angle with a plane parallel to the support and the second portion forms a fourth angle with the plane, the third angle being smaller than the fourth angle. Preferably, the second portion forms a fourth angle with the plane parallel to the support and the first portion forms a fifth angle with the plane, the fourth angle being smaller than the fifth angle.

According to a third aspect of the invention, in an idle state of the zip guide, in an orthogonal projection onto a plane perpendicular to a plane of the support the third portion has a third length greater than a second length of the second portion. Preferably, in an orthogonal projection onto a plane perpendicular to a surface of the support, the first portion has a first length greater than a second length of the second portion and greater than a third length of the third portion.

A zip guide according to the invention may comprise one or more of the first, second and third aspects. With each of these aspects, in particular due to the different angular magnitudes and/or different lengths, the above mentioned variable and stepwise increasing resilience with increasing load of the screen cloth on the zip guide is advantageously achieved.

It goes without saying that the resilient member can comprise more than three portions, which are arranged in a zigzag shape and wherein the angular magnitudes between the successive portions can be different.

According to the invention, there is also provided a screen device as set out in the present claims. The screen device comprises, for a single screen cloth, at least one, preferably two of the zip guides from the first aspect. It is possible to provide screen devices with several screen cloths arranged next to one another (so-called coupled screen devices), wherein for each screen cloth two zip guides are provided.

Aspects of the invention will be explained in the following detailed description with reference to the appended drawings. Whenever the same reference numeral is used in the drawings, this refers to the same feature.

With reference to <FIG>, a screen device <NUM> generally comprises a roller shaft <NUM> and a pair of side guides <NUM>, <NUM> arranged at the ends of the roller shaft <NUM>. The (screen) cloth <NUM> is unrolled from the roller shaft <NUM> according to a winding direction <NUM>, in which the sides <NUM>, <NUM> (lateral ends) of the cloth <NUM> move in the corresponding side guides <NUM>, <NUM>. The roller shaft <NUM> may be arranged in a roller box <NUM>, which forms a housing that protects the cloth <NUM> against environmental influences when the cloth is rolled up on the roller shaft <NUM>. A bottom bar <NUM> can be provided on the underside of the cloth <NUM>. The bottom bar <NUM> can comprise a rod of a heavier material (e.g. steel) to assist the downward movement of the cloth <NUM>.

In the context of the present invention, the term cloth should be interpreted as any fabric, woven or not, that can be rolled up and serve as a shield against weather influences (e.g. sun) or environmental influences (e.g. insects). The cloth <NUM> is preferably a so-called "screen" for shielding against solar radiation and is preferably made of synthetic material, such as, for example, polyester. The screen device <NUM> can be configured to shield an opening in a building, such as a window or door opening, or as covering and/or shielding of, for example, a terrace.

The cloth <NUM> can be attached to the roller shaft <NUM> according to known techniques, such as by gluing to a cloth fastening profile which further engages in a slot in the roller shaft (not shown). Alternatively, it is possible to apply a thickening at the end of the cloth <NUM> and have this thickening engage in a slot in the roller shaft <NUM>.

With reference to <FIG>, the cloth <NUM> is provided on both lateral ends <NUM>, <NUM> with thickenings, so-called zips <NUM>, which are fixedly attached to the cloth. The zips <NUM> can be applied using known techniques, e.g. by gluing or welding.

With reference to <FIG>, each of the side guides <NUM>, <NUM> comprises a housing <NUM> provided for attachment to a wall or partition <NUM>. The housing <NUM> is preferably made of an extruded material, such as aluminum, and can be configured to be attached to the wall <NUM> via screws <NUM>. The housing <NUM> can include one or more mounting profiles <NUM>, <NUM>, which are configured to be mounted in or on top of each other to form the housing <NUM>. The housing <NUM> can be configured for outside mount or inside mount.

The housing <NUM> of the side guides <NUM>, <NUM> comprises a chamber <NUM> configured to accommodate a zip guide <NUM>. The chamber <NUM> comprises an outer wall <NUM>, located on the side of the cloth <NUM>. An access slot <NUM> extending in the winding direction <NUM> of the cloth <NUM> is provided in the outer wall <NUM> and provides access to the chamber <NUM>. The access slot <NUM> divides the outer wall <NUM> into two portions <NUM>' and <NUM>" extending on either side of the access slot <NUM>. Both portions <NUM>' and <NUM>" form walls of chamber <NUM>. The portions <NUM>' and <NUM>" can have an L-shaped cross-section, in which one leg of the "L" extends along the direction of the access slot.

The zip guide <NUM> comprises a support <NUM> with a guide <NUM> for the zip <NUM> attached thereto. The zip guide <NUM> further comprises two resilient members <NUM>, <NUM>' arranged on either side of the guide <NUM>. The resilient members <NUM>, <NUM>' are configured to resiliently mount the zip guide <NUM> relative to the housing <NUM>.

With reference to <FIG>, the support <NUM> is elongated, with a longitudinal direction <NUM> according to the winding direction of the cloth <NUM>. The support <NUM> preferably has a substantially rectangular cross-section and is therefore substantially plate-shaped. The support <NUM> comprises a preferably flat front side 171a and rear side 171b. In the present example, the guide <NUM> and the two resilient members <NUM>, <NUM>' are arranged on the front side 171a of the support <NUM>, though other embodiments are possible. The guide <NUM> comprises a chamber <NUM> extending in a longitudinal direction <NUM> which is configured to house the zip <NUM>. An access slot <NUM> running in parallel to the longitudinal direction of the chamber <NUM> provides access thereto. The access slot <NUM> preferably has a width that is smaller than the zip <NUM> to prevent the zip from being pulled out of the chamber <NUM>.

When assembling the zip guide, as shown in <FIG>, the access slot <NUM> is directed towards the cloth <NUM>. The access slot <NUM> is preferably provided in a wall of the chamber <NUM> which is in a raised position relative to the support <NUM>. Preferably, the chamber <NUM> is formed by two ribs <NUM>, <NUM> substantially facing each other which are arranged side by side on the support <NUM>, thus enclosing a volume, which forms the chamber <NUM>. The ribs <NUM>, <NUM> are preferably substantially L-shaped, but a different configuration, preferably adapted to the shape of the zip <NUM>, is also possible.

The support <NUM> preferably protrudes laterally on both sides of the guide <NUM>. The pair of resilient members <NUM>, <NUM>' is attached to these laterally projecting parts of the support <NUM>.

Each of the resilient members <NUM>, <NUM>' is illustratively three-membered, with three members foldably attached to each other: a first member <NUM>, a second member <NUM> and a third member <NUM>. Each of the three members <NUM>, <NUM>, <NUM> is preferably slat-shaped, with a substantially rectangular cross-section. It is possible to provide more than three members; for example, each of the resilient members can be four- or five-membered. A first member <NUM> is attached with a first side to the support <NUM> and is connected with a second, opposite side to a first side of the second member <NUM>. The first member <NUM> and the second member <NUM> are secured adjacent to each other via a first folding rib <NUM>, so that the second member <NUM> can pivot about the first folding rib <NUM> relative to the first member <NUM>. The second member <NUM> is connected with a second side opposite the first side of the second member to a first side of the third member <NUM>. The second member <NUM> and the third member <NUM> are attached adjacent to each other via a second folding rib <NUM>, so that the third member <NUM> can pivot about the second folding rib <NUM> relative to the second member <NUM>. The third member <NUM> preferably has a free end.

In an idle state (unloaded state), in which no forces are exerted on the resilient members <NUM>, <NUM>', the three members <NUM>, <NUM> and <NUM> are arranged at an angle to each other, such that they are arranged in a zigzag shape. More specifically, the concave sides formed by the first member <NUM>, the first folding rib <NUM> and the second member <NUM> on the one hand, and by the second member <NUM>, the second folding rib <NUM> and the third member <NUM> on the other hand, are located on opposite sides of the corresponding resilient member. The folding ribs <NUM>, <NUM> are set to arrange the respective adjacent members at a predetermined angle and are additionally set to provide a certain resistance to an angle change. A resilient effect is hereby obtained. The resilient effect can be further adjusted by appropriately shaping the folding ribs <NUM>, <NUM>.

The two resilient members <NUM>, <NUM>' are preferably mirror-symmetrical with respect to a median plane of the zip guide <NUM> along the longitudinal direction <NUM> and perpendicular to the plane <NUM> of the support <NUM>.

According to an aspect of the invention, the three members <NUM>, <NUM>, <NUM> are arranged at different angles in an idle state of the zip guide. A first angle α between the first member <NUM> and the second member <NUM> (i.e., the angle of the first folding rib <NUM>) is preferably greater in absolute value than a second angle β between the second member <NUM> and the third member <NUM> (i.e., the angle of the second folding rib <NUM>). By making the angles α and β different from each other, a stepwise resilient effect is easily obtained, with variable resilience that preferably increases with increasing deformation or compression. Since the second angle β is smaller, this angle will be excited first at a small load. Due to the smaller second angle β, the second folding rib <NUM> will offer a lower resistance to deformation compared to the first folding rib <NUM>. As a result, the third member <NUM> will fold (pivot relative to the second folding rib <NUM>) first. Since the first angle α is larger, it will only be excited at higher loads, and the second member <NUM> will therefore only fold (pivot relative to the first folding rib <NUM>) at higher loads. Preferably, the difference between the absolute values of the first angle α and the second angle β is at least <NUM>°, preferably at least <NUM>°, preferably at least <NUM>°, and preferably less than or equal to <NUM>°, preferably less than or equal to <NUM>°. The first angle α preferably lies in absolute value between <NUM>° and <NUM>°, preferably between <NUM>° and <NUM>°, preferably between <NUM>° and <NUM>°. The second angle β preferably lies in absolute value between <NUM>° and <NUM>°, preferably between <NUM>° and <NUM>°, preferably between <NUM>° and <NUM>°. With such large angles, greater distances can advantageously be bridged by the resilient member.

According to an alternative approach, the adjustment angle of each of the first, second and third members relative to the plane <NUM> of the support <NUM> (or any plane parallel to plane <NUM>) is considered. The third member <NUM> is arranged at a third angle γ with respect to the plane <NUM>. The second member <NUM> is arranged at a fourth angle δ relative to the plane <NUM>. The first member <NUM> is arranged at a fifth angle ε with respect to the plane <NUM>. In this case, preferably, the third angle γ is smaller in absolute value than the fourth angle δ. Preferably, the fourth angle δ is smaller in absolute value than the fifth angle ε. Preferably, the difference between the absolute values of the fourth angle δ and the third angle γ is at least <NUM>°, preferably at least <NUM>°, preferably between <NUM>° and <NUM>°. Preferably, the difference between the absolute values of the fifth angle ε and the fourth angle δ is at least <NUM>°, preferably at least <NUM>°, preferably between <NUM>° and <NUM>°. Preferably, the third angle γ is between <NUM>° and <NUM>°, preferably between <NUM>° and <NUM>°. Preferably, the fourth angle δ is between <NUM>° and <NUM>°, preferably between <NUM>° and <NUM>°. Preferably, the fifth angle ε is between <NUM>° and <NUM>°, preferably between <NUM>° and <NUM>°. Thus, a stepwise resilient effect is also obtained as described above.

The arrangements with first angle α and second angle β on the one hand and with third angle γ, fourth angle δ and fifth angle ε on the other, as described above, can further be combined with each other.

An established advantage of such a stepwise resilient effect is that with smaller loads on the resilient members, the friction between the zip <NUM> and the guide <NUM> remains limited when the cloth <NUM> is rolled up and down, which leads to a longer service life without further costs or interventions being required.

Such stepwise resilient effect is further enhanced when the first member <NUM> is attached to the support <NUM> in a fixed orientation (non-foldable), preferably an orientation with a fifth angle ε as described above. It is hereby obtained that the first member <NUM> will behave like a cantilever beam, being clamped at the point of attachment with the support <NUM>. This prevents a pivoting action of the first member <NUM>, which will only deform by cantilevering, and is therefore only excited at extreme loads, as shown in <FIG>. At increasing load, the second and third members <NUM>, <NUM> will first fold towards each other as much as possible. Thereby, the second folding rib <NUM> is preferably configured to fold completely, wherein the second angle β as well as the fourth angle δ become practically <NUM>. Only in a subsequent stage, a deformation of the first member is excited.

Referring again to <FIG>, the first member <NUM>, the second member <NUM> and the third member <NUM> preferably have different lengths. Measured in a direction perpendicular to the plane <NUM> of the support <NUM>, it is advantageous that the length L<NUM> of the first member <NUM> is greater than the length L<NUM> of the second member <NUM> and the length L<NUM> of the third member <NUM>. The lengths L<NUM> of the second member <NUM> and L<NUM> of the third member <NUM> can be equal or different. Preferably L<NUM> is greater than L<NUM>, so that L<NUM> > L<NUM> > L<NUM>. By so doing it is obtained that, when the second and third members are fully folded, the first folding rib <NUM>, in orthogonal projection on the plane <NUM>, is located between the sides (ends) of the third member <NUM>, such that the action of forces of the first member <NUM> is optimally utilized with greater resistance to deformation. This can lead to better stability of the zip guide under load and a greater variation of the resilience. Alternatively, it is possible to make L<NUM> at least as long as L<NUM>, i.e. L<NUM> > L<NUM> ≥ L<NUM>.

The resilient members <NUM>, <NUM>' are preferably arranged such that the members at the free end (the third members <NUM> in the present example) are directed away from each other when viewed in a direction from the support towards the cloth. The orientation of the other members then follows logically when a zigzag shape is assumed. By way of example, the second members <NUM> face each other and the first members <NUM> are directed away from each other.

It is advantageous to manufacture the resilient members <NUM>, <NUM>' on the one hand and the support <NUM> and guide <NUM> on the other hand from different materials. The support and the guide are preferably made of a harder material, such as a hard plastic, e.g. polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), or a combination of both. The resilient members are preferably made of a softer and preferably resilient material, such as an elastomer, e.g. ethylene propylene diene monomer (EPDM) or polyurethane (PUR), preferably a PUR with shape memory, so that the spring pressure is guaranteed for longer. Preferably, the members and the folding ribs of the resilient members are manufactured from the same (synthetic) material, in which the folding ribs are obtained by providing a weakening, such as, for example, a removal of material. The zip guide is preferably made by co-extrusion of the harder material for the support and guide and the softer material for the resilient members. As a result, a simple and better clamping of the first member to the support can be obtained. In addition, the zip guide is ready for use after extrusion and no further actions are required to mount the resilient members, so that this manufacturing method is cost effective. It is of course possible to manufacture the zip guide according to other known techniques.

Claim 1:
Zip guide (<NUM>) for guiding a zip (<NUM>) provided on a lateral side of a screen cloth (<NUM>), the zip guide comprising:
a support (<NUM>),
a guide (<NUM>) configured to guide the zip (<NUM>),
a first resilient member (<NUM>) and a second resilient member (<NUM>'), arranged on either side of the guide (<NUM>),
wherein each of the first and second resilient members comprises a first portion (<NUM>), a second portion (<NUM>) and a third portion (<NUM>) arranged sequentially from the support (<NUM>) onwards, wherein each two adjacent portions of the first, the second and the third portions are hingedly attached to each other via a folding rib (<NUM>, <NUM>),
wherein the first portion (<NUM>) and the second portion (<NUM>) form two first adjacent portions and the second portion (<NUM>) and the third portion (<NUM>) form two second adjacent portions,
wherein the first portion is adjacent to the support (<NUM>) and the third portion (<NUM>) is farther from the support than the first portion and than the second portion (<NUM>),
characterised in that the first portion (<NUM>) is clamped to the support (<NUM>) so as to prevent pivoting action of the first portion relative to the support, and
in that in an idle state, the first portion (<NUM>) and the second portion (<NUM>) are folded towards each other at a first angle (α), and the second portion (<NUM>) and the third portion (<NUM>) are folded towards each other at a second angle (β), wherein the second angle (β) is arranged farther from the support (<NUM>) than the first angle (α), wherein in absolute values the second angle (β) is smaller than the first angle (α).