Roller shade

A roller shade includes a light shielding sheet which can be rolled up in a roll shape, a roller and an electric motor for openably moving the light shielding sheet, guide belts connected to respective lower surfaces of side end parts of the light shielding sheet in a sheet width direction, and a pair of guide parts each having a guide space which receives a corresponding one of the side end parts of the light shielding sheet in the sheet width direction and a corresponding one of the guide belts, for guiding the side end part and the guide belt. In the roller shade, the light shielding sheet is prevented from being creased when the light shielding sheet moves in the width direction while being rolled or unrolled, due to lack of a tension of the light shielding sheet in the width direction.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. national phase application of International Application No. PCT/EP2013/056597, filed Mar. 27, 2013, which claims benefit of the priority date of Japan Application 2012-085898, filed Apr. 4, 2012, which are hereby incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to roller shades attached to a window formed in a roof of a vehicle.

As a roller shade of this type, a device that includes a light shielding sheet which can be rolled up in a roll shape and unrolled, a pair of guide belts each connected to a corresponding one of side ends of the light shielding sheet in a width direction, and a pair of guide parts each guiding a corresponding one of the side ends of the light shielding sheet in the width direction along with the guide belt, has been known (see, for example, Japanese Patent Publication No. 2011-6011). In this roller shade, the guide belt is configured such that one of its surfaces in a thickness direction forms an arc shape, i.e., a convex surface in a cross-sectional view taken along the width direction of the light shielding sheet. A middle portion of the convex surface of each guide belt in the width direction is connected to a corresponding one of the side ends of the light shielding sheet in the width direction. Edges of each guide belt in a sheet width direction are engaged with a pair of engagement portions of the guide part. The pair of engagement portions are connected to each other via a bottom wall portion located under the guide belt. An arc space surrounded by the engagement portions and the bottom wall portion forms a guide space.

SUMMARY OF INVENTION

In the above roller shade, the light shielding sheet may move in the width direction (in a direction orthogonal to the sheet moving direction) during rolling and unrolling the light shielding sheet, due to variations in dimensions of the light shielding sheet, inaccuracies in assembling the roller shade, etc. If this direction in which the light shielding sheet moves is, for example, a direction which makes the guide belt away from the inner side one of the engagement portions in the sheet width direction, the tension of the light shielding sheet in the width direction becomes insufficient. This may cause the light shielding sheet to become wrinkled, and the wrinkle may cause trouble in rolling up the light shielding sheet.

To avoid such a trouble, it is preferable to reduce the variations in dimensions of the light shielding sheet and inaccuracies in assembling the roller shade as much as possible. However, to achieve that, it is necessary to raise the inaccuracy control level in the assembly step, or increase fabrication accuracy of each component (such as the light shielding sheet and the guide part), and there are limitations in terms of the number of assembly steps and cost.

The present disclosure is thus intended to provide a roller shade which can prevent a reduction in tension of the light shielding sheet in the width direction even if the light shielding sheet moves in the width direction in a rolling/unrolling movement, in a simple structure at low cost.

The first aspect of the present disclosure is directed to a roller shade, including: a light shielding sheet which can be rolled up in a roll shape or can be unrolled and which covers a window formed in a roof of a vehicle so as to open/close the window; rolling means configured to move the light shielding sheet in an opening direction of the window by rolling up the light shielding sheet and move the light shielding sheet in a closing direction of the window by unrolling the light shielding sheet; a pair of strip-shaped guide belts each extending along a corresponding one of side end parts of the light shielding sheet in a sheet width direction perpendicular to a traveling direction of the light shielding sheet and each connected to a lower surface of the light shielding sheet; and a pair of guide parts each having a guide space which receives a corresponding one of the side end parts of the light shielding sheet in the sheet width direction and a corresponding one of the guide belts, for guiding the side end part and the guide belt in the traveling direction.

Each guide belt tilts downward from a base end which is a connection part of the guide belt with the light shielding sheet, toward an inner side in the sheet width direction, and is vertically flexible about the connection part as a point of support, and an inner wall surface of the guide space includes an inclined surface part which is located near the guide belt and closer to the inner side in the sheet width direction than the guide belt, and which extends upward to tilt to an outer side in the sheet width direction.

According to the first aspect of the present disclosure, if the light shielding sheet moves in a direction in which the guide belt approaches the inclined surface part of the guide part due to variations in dimensions of the light shielding sheet or inaccuracies in assembling the roller shade, the inner end part of the guide belt in the sheet width direction comes in contact with the inclined surface part, thereby preventing the guide belt from protruding out of the guide space.

Here, the guide belt is configured to be vertically flexible about the connection part of the guide belt with the light shielding sheet, as a point of support. Thus, in the state in which an inner end part of the guide belt in the sheet width direction contacts the inclined surface part, the inner end part of the guide belt in the sheet width direction slides downward along the inclined surface part as the guide belt moves toward the inclined surface part (toward the inner side in the sheet width direction), and the guide belt warps downward about the connection part with the light shielding sheet. As a result, a load acting on the light shielding sheet in the sheet width direction can be diverted and relieved, and therefore excessive tension in the sheet width direction can be prevented from acting on the light shielding sheet.

If the guide belt moves toward an outer side in the sheet width direction, that is, away from the inclined surface part, in a state in which the guide belt is warped downward about the connection part as a point of support due to contact between the inner end part of the guide belt in the sheet width direction and the inclined surface part, the inner end part of the guide belt in the sheet width direction slides upward along the inclined surface part in an inclination direction thereof, and an inclination angle of the guide belt with respect to the light shielding sheet is decreased by restoring force of the guide belt.

Thus, even when the light shielding sheet moves such that the guide belt is apart from the inclined surface part, tension in the sheet width direction can be constantly provided to the light shielding sheet by the restoring force of the guide belt. As a result, it is possible to reduce wrinkling of the light shielding sheet due to significant reduction in tension of the light shielding sheet in the sheet width direction or winding failure of the light shielding sheet due to the wrinkling of the light shielding sheet.

The second aspect of the present disclosure is that in the first aspect of the present disclosure, if the light shielding sheet moves, in a direction in which each guide belt is apart from the inclined surface part, in a state in which the each guide belt downwardly warps about the point of support which is the connection part due to contact between an inner end part of the each guide belt in the sheet width direction and the inclined surface part, the inner end part of the each guide belt in the sheet width direction upwardly slides along the inclined surface part in an inclination direction thereof while an inclination angle of the each guide belt with respect to the light shielding sheet is decreased by restoring force of the each guide belt which warps, thereby providing tension in the sheet width direction to the light shielding sheet.

According to the second aspect of the present disclosure, advantages similar to the advantages according to the first aspect can be reliably obtained.

The third aspect of the present disclosure is that in the first or second aspect of the present disclosure, a vertical length of the guide space on the outer side in the sheet width direction is shorter than a vertical length of the guide space on the inner side in the sheet width direction.

According to the third aspect of the present disclosure, a vertical length of the guide space is shorter on the outer side in the sheet width direction than the inner side in the sheet width direction. Thus, in the state in which the inner end part of the guide belt in the sheet width direction is apart from the inclined surface part, the guide belt is not guided by the inclined surface part, but instead, the end part of the light shielding sheet in the sheet width direction, together with the guide belt, can be securely guided by the guide space on the outer side in the sheet width direction where the vertical length is short. Thus, the light shielding sheet can be guided with reliability.

On the other hand, the vertical length of the guide space on the inner side in the sheet width direction is larger than the vertical length of the guide space on the outer side. Thus, in the state in which the inner end part of the guide belt in the sheet width direction contacts the inclined surface part, the inclination angle of the guide belt with respect to the light shielding sheet is large, and therefore sufficient height at which the guide belt is caught by the inclined surface part can be ensured. As a result, it is possible to reliably prevent the guide belt from protruding out of the guide space.

The fourth aspect of the present disclosure is that in the third aspect of the present disclosure, a part of a lower surface of the guide space on the outer side in the sheet width direction is positioned higher than a part of the lower surface of the guide space on the inner side in the sheet width direction.

According to the fourth aspect of the present disclosure, in the state in which the guide belt is significantly apart from the inclined surface part, the end part of the light shielding sheet in the sheet width direction, together with the guide belt, can be supported as high as possible by the lower surface of the guide space. This can reduce weighing-down of the end part of the light shielding sheet in the sheet width direction, and therefore, it is possible to prevent deformation of the light shielding sheet, and degradation of appearance of the light shielding sheet.

ADVANTAGES OF INVENTION

As described above, according to the roller shade of the present disclosure, the guide belt is configured to tilt downward from a base end which is a connection part of the guide belt with the light shielding sheet, toward an inner side in the sheet width direction, and to be vertically flexible about the connection part as a point of support. Further, an inner wall surface of the guide space includes an inclined surface part which is located near the guide belt and closer to the inner side in the sheet width direction than the guide belt, and which extends upward to tilt to the outer side in the sheet width direction. With this structure, even when the light shielding sheet moves in the sheet width direction, wrinkling of the light shielding sheet due to reduction in tension of the light shielding sheet in the sheet width direction or winding failure of the light shielding sheet due to the wrinkling of the light shielding sheet can be prevented with reliability.

DESCRIPTION OF EMBODIMENTS

FIG. 1illustrates a vehicle roof part2to which a roller shade1of an embodiment of the present disclosure is attached. A window5formed by fitting a glass panel in a substantially-rectangular opening4is formed in a roof panel3of the vehicle roof part2. The window5functions as a light transmission part through which sunlight enters a vehicle compartment. In the description below, a “front” and a “rear” means a front side and a rear side of a vehicle, respectively.

The roller shade1is an electric roller shade driven by an electric motor. The roller shade1is arranged below the window5, and includes a light shielding sheet11which can be rolled up in a roll or can be unrolled. The roller shade1is configured to block direct sunlight in such a manner that the window5is covered by the unrolled light shielding sheet11.

Referring toFIG. 2, the roller shade1includes a pair of guide frames12each made of aluminum and extending in a front-back direction along a corresponding one of side end parts of the window5in a vehicle width direction, a resin frame13connecting front end parts of the guide frames12together, and a roller14supported, at end parts thereof in a shaft direction, by rear end parts of the guide frames12.

The resin frame13is in a U-shape in which the resin frame13opens at the rear as viewed in the plane. An electric motor (not shown in the figure) and a drive gear15driven by the electric motor are attached to a middle part of the resin frame13in the vehicle width direction. A geared cable16having an outer peripheral surface at which a gear part is formed is engaged with the drive gear15.

The light shielding sheet11is wound around the roller14so as to be rolled up or unrolled. An end of the light shielding sheet11on an unrolled side on which the light shielding sheet11is unrolled is a free end, and an end of the light shielding sheet11opposite to the unrolled side is a fixed end fixed to the roller14. A garnish17extending in the vehicle width direction along the end of the light shielding sheet11on the unrolled side is connected to the end of the light shielding sheet11on the unrolled side. A runner part (not shown in the figure) which is slidable back and forth is provided along the guide frame12in each of end parts of the garnish17in the vehicle width direction. The runner parts are connected to the geared cable16. When the motor rotates, the geared cable16is driven by the drive gear15to move the runner parts back and forth. While the runner parts move back and forth, the light shielding sheet11also moves, together with the runner parts (garnish17), in the front-back direction so as to open/close the window5.

The light shielding sheet11is constantly biased toward a roll-up side by a biasing mechanism built in the roller14. In the present embodiment, when the light shielding sheet11is wound around the roller14, the light shielding sheet11moves in an opening direction (i.e., toward the rear). When the light shielding sheet11is unrolled from the roller14, the light shielding sheet11moves in a closing direction (i.e., toward the front). The direction perpendicular to the traveling direction of the light shielding sheet11is coincident with a width direction of the light shielding sheet11and the vehicle width direction.

Referring toFIG. 3, a strip-shaped guide belt18extending along each of side end parts of the light shielding sheet11in the width direction thereof is connected to a lower surface of the side end part of the light shielding sheet11. The guide belt18is made of a resin material in the present embodiment, but the present disclosure is not limited to such a material. For example, the guide belt18may be made of an elastic material such as rubber. The guide belt18and the light shielding sheet11are connected together by sewing, and a sewing line extends straight along each of the side end parts of the light shielding sheet11in the width direction thereof.

The guide belt18downwardly tilts from a base end, i.e., a connection part10(sewing part) with the light shielding sheet11, toward an inner side in the sheet width direction, and is vertically flexible about a point of support, i.e., the connection part10. In the state (seeFIG. 3) in which no external force acts on the guide belt18, an inclination angle θ of the guide belt18with respect to the light shielding sheet11is a predetermined neutral angle θN(<90°). When external force acts on the guide belt18such that the inclination angle θ of the guide belt18with respect to the light shielding sheet11is less than the neutral angle θN, restoring force in a direction (downward direction) in which the inclination angle θ is increased acts on the guide belt18. When external force acts on the guide belt18such that the inclination angle θ is greater than the neutral angle θN, restoring force in a direction (upward direction) in which the inclination angle θ is decreased acts on the guide belt18. The neutral angle θNis an angle determined depending on, e.g., materials of the light shielding sheet11, the guide belt18, and a thread for sewing.

A guide part19extending in the front-back direction is formed in each of end parts of the guide frame12on an inner side in the vehicle width direction. In the guide part19, a guide space20is formed, in which each of the side end parts of the light shielding sheet11in the width direction thereof is, together with the guide belt18, accommodated and is guided so as to move in the front-back direction.

Referring toFIGS. 3-5, the guide part19includes a vertically-extending upstanding wall part25positioned on an outer side in the sheet width direction relative to the side end part of the light shielding sheet11in the width direction thereof, an upper wall part26inwardly extending in the sheet width direction from an upper end part of the upstanding wall part25, a lower wall part27inwardly extending in the sheet width direction from a lower end part of the upstanding wall part25, and a protruding wall part28upwardly protruding from an inner end part of the lower wall part27in the sheet width direction.

The upper wall part26extends in the front-back direction so as to cover an upper part of the side end part of the light shielding sheet11in the width direction thereof, and the lower wall part27extends in the front-back direction so as to cover a lower part of the guide belt18in the state in which the lower wall part27faces the upper wall part26. The protruding wall part28is positioned below the light shielding sheet11on the inner side in the sheet width direction relative to the guide belt18. An insertion hole21through which the light shielding sheet11is inserted is formed between an inner end part of the upper wall part26in the sheet width direction and an upper end part of the protruding wall part28.

The guide space20is formed so as to be surrounded by the wall parts25-28. A vertical distance between the upper wall part26and the lower wall part27is smaller on the outer side in the sheet width direction than on the inner side in the sheet width direction, and therefore the vertical length of the guide space20is smaller on the outer side in the sheet width direction than on the inner side in the sheet width direction. Specifically, the guide space20includes an inner guide space20apositioned adjacent to the protruding wall part28on the inner side in the sheet width direction, and an outer guide space20bpositioned adjacent to the upstanding wall part25on the outer side in the sheet width direction. The vertical length Hb(seeFIG. 5(b)) of the outer guide space20bis smaller than the vertical length Haof the inner guide space20a.

An inner wall surface in the guide space20includes a horizontal surface part30defining a lower surface of the upper wall part26, a vertical surface part29defining a surface of the upstanding wall part25on the inner side in the sheet width direction, a step-shaped surface part31having double steps and defining an upper surface of the lower wall part27, and an inclined surface part32defining a surface of the protruding wall part28on the outer side in the sheet width direction.

The step-shaped surface part31defining the upper surface of the lower wall part27includes an outer horizontal surface27apositioned adjacent to the upstanding wall part25, and an inner horizontal surface27bpositioned on the inner side in the sheet width direction relative to the outer horizontal surface27a. The outer horizontal surface27ais positioned higher than the inner horizontal surface27b. An inner end part of the outer horizontal surface27ain the sheet width direction and an outer end part of the inner horizontal surface27bin the sheet width direction are connected together through a connection surface27c. The connection surface27cdownwardly tilts to the inner side in the sheet width direction.

The inclined surface part32is positioned adjacent to the guide belt18on the inner side in the sheet width direction, and upwardly tilts to the outer side in the sheet width direction. The inclination angle θKof the inclined surface part32with respect to the inner horizontal surface27bis greater than the neutral angle θNwhich is the inclination angle of the guide belt18in a neutral state.

Next, a function to guide the light shielding sheet11and the guide belt18in the guide space20will be described with reference toFIGS. 4(a)-4(c).

FIG. 4(a) illustrates the state in which there is a predetermined clearance between an inner end part of the guide belt18and the inclined surface part32of the protruding wall part28. In such a state, the light shielding sheet11is guided with part of an upper surface of the light shielding sheet11contacting the upper wall part26, and is guided with a lower surface of the light shielding sheet11contacting the upper end part of the protruding wall part28.

Suppose that, while the light shielding sheet11moves to open/close the window5, the light shielding sheet11moves in a direction in which the guide belt18approaches the inclined surface part32(i.e., in a direction indicated by a black arrow inFIGS. 4(a)-4(c)). The distance between the inner end part of the guide belt18in the sheet width direction and the inclined surface part32of the protruding wall part28is gradually shortened, and the inner end part of the guide belt18eventually comes into contact with the inclined surface part32(seeFIG. 4(b)). Then, when the light shielding sheet11further moves from the foregoing state in the direction indicated by the thick arrow, the inner end part of the guide belt18in the sheet width direction downwardly slides along the inclined surface part32in an inclination direction thereof. As a result, the guide belt18downwardly warps about the point of support, i.e., the connection part10of the guide belt18with the light shielding sheet11. Consequently, the inclination angle (open angle) of the guide belt18with respect to the light shielding sheet11is increased. Thus, in such a manner that the guide belt18downwardly warps, a load acting on the light shielding sheet11in the sheet width direction can be diverted and relieved, and therefore excessive tension in the sheet width direction can be prevented from acting on the light shielding sheet11. As the guide belt18approaches the inclined surface part32, the height h at which the guide belt18is caught by the protruding wall part28is increased. Thus, it can be ensured that the guide belt18is prevented from protruding out of the guide space20through the insertion hole21(seeFIG. 4(c)).

On the other hand, if the light shielding sheet11moves in a direction in which the guide belt18is apart from the inclined surface part32, an inverse process is performed. That is, referring to the state illustrated inFIG. 4(c), the guide belt18downwardly warps about the point of support, i.e., the connection part10of the guide belt18with the light shielding sheet11in such a manner that the inner end part of the guide belt18in the sheet width direction contacts with the inclined surface part32. When the light shielding sheet11further moves from the foregoing state in the direction in which the guide belt18is apart from the inclined surface part32(i.e., in a direction indicated by a white arrow inFIGS. 4(a)-4(c)), the inner end part of the guide belt18in the sheet width direction upwardly slides, referring toFIG. 4(b), along the inclined surface part32in the inclination direction thereof, and the inclination angle θ with respect to the light shielding sheet11is decreased by restoring force of the guide belt18. Thus, even when the light shielding sheet11moves such that the guide belt18is apart from the inclined surface part32, tension in the sheet width direction can be constantly provided to the light shielding sheet11by using restoring force of the guide belt18. Consequently, wrinkling of the light shielding sheet11due to significant reduction in tension of the light shielding sheet11in the sheet width direction or winding failure of the light shielding sheet11due to the wrinkling of the light shielding sheet11can be reduced or prevented.

When the light shielding sheet11further moves from the state illustrated inFIG. 4(b) in the direction indicated by the white arrow, the inner end part of the guide belt18in the sheet width direction is completely apart from the inclined surface part32, resulting in the state illustrated inFIG. 4(a).

If the distance between the inner end part of the guide belt18and the inclined surface part32is large, the end part of the light shielding sheet11in the width direction thereof is likely to be weighed down with the light shielding sheet11itself about a point of support, i.e., part near the contact part of the light shielding sheet11and the protruding wall part28. Thus, if the upper surface of the lower wall part27defines a horizontal surface with no step as illustrated in, e.g.,FIG. 5(a), the light shielding sheet11is upwardly raised at the part near the contact part of the light shielding sheet11and the protruding wall part28as viewed from an inside of a vehicle compartment. As a result, there is a disadvantage that an appearance of the light shielding sheet11as viewed from a passenger inside the vehicle compartment is degraded.

On the other hand, in the present embodiment, part (outer horizontal surface27a) of the upper surface of the lower wall part27of the guide part19(i.e., a lower surface in the guide space20) on the outer side in the sheet width direction is, as described above, formed at a position one step higher than that of part (inner horizontal surface27b) of the upper surface of the lower wall part27on the inner side in the sheet width direction. Thus, even if the distance between the guide belt18and the inclined surface part32is large as illustrated inFIG. 5(b), the end part of the light shielding sheet11in the width direction thereof is supported as high as possible by the outer horizontal surface27a. This can reduce or prevent weighing-down of the light shielding sheet11. Consequently, there is no disadvantage that the appearance is degraded.

Moreover, in the present embodiment, the guide space20is formed such that the vertical length is smaller in part of the guide space20on the outer side in the sheet width direction than in part of the guide space20on the inner side in the sheet width direction.

Thus, in the state in which the inner end part of the guide belt18in the sheet width direction is apart from the inclined surface part32, the end part of the light shielding sheet11in the width direction thereof and the guide belt18can be, instead of guiding the guide belt18by the inclined surface part32, guided without vertical fluttering in the outer guide space20bhaving a smaller vertical length. Consequently, stable opening/closing with the light shielding sheet11can be realized, and wrinkling of the light shielding sheet11or winding failure of the light shielding sheet11can be reduced or prevented.

The vertical length is greater in part of the guide space20on the inner side in the sheet width direction than in part of the guide space20on the outer side in the sheet width direction. Thus, in the state (see the state illustrated inFIGS. 4(b) and4(c)) in which the inner end part of the guide belt18in the sheet width direction contacts the inclined surface part32, the inclination angle θ of the guide belt18is large, and therefore the sufficient height h at which the guide belt18is caught by the inclined surface part32can be ensured. As a result, it can be ensured that the guide belt18is prevented from protruding out of the guide space20through the insertion hole21.

The configuration of the present disclosure is not limited to the foregoing embodiment, and may have various configurations other than the foregoing configuration. That is, in the foregoing embodiment, the roller shade1is the electric roller shade configured to open/close the window5with the light shielding sheet11by the electric motor. However, the present disclosure is not limited to such a roller shade, and the roller shade1may be a roller shade configured to manually open/close a window with a light shielding sheet as in Japanese Patent Publication No. 2001-180279.

In the foregoing embodiment, the guide belt18is connected to the lower surface of the light shielding sheet11by sewing. However, the present disclosure is not limited to such a configuration, and the guide belt18may be connected to the lower surface of the light shielding sheet11by, e.g., bonding or welding.

In the present embodiment, the entirety of an outer side surface of the protruding wall part28in the sheet width direction defines the inclined surface part32. However, the inclined surface part32may be formed only in the upper end part of the protruding wall part28, for example.

In the foregoing embodiment, the traveling direction (i.e., a direction in which the guide frame12extends) of the light shielding sheet11is the front-back direction of the vehicle. However, the present disclosure is not limited to such a configuration, and the traveling direction of the light shielding sheet11may be, e.g., the vehicle width direction.

The present disclosure is useful for the roller shade, and particularly for the electrical roller shade.