Device for conveying and retaining a glass sheet, particularly in a washing facility

Abstract

A device for conveying and holding a sheet of glass, includes a conveyor and a holder configured to hold a sheet of glass in position, in particular in a horizontal position, wherein the conveyor comprises at least two spaced-apart and parallel lateral conveying systems extending longitudinally in the conveying direction and intended to be positioned in such a way as to support the lateral sides of the sheet of glass, and the holder comprises at least one holding system placed above the lateral conveying systems and above the sheet of glass and intended to limit the amplitude of the movements of the sheet of glass.

Claims

1. A device for conveying and holding a sheet of glass, comprising a conveyor and a holder configured to hold a sheet of glass in position, wherein the conveyor comprises at least two spaced-apart and parallel lateral conveying systems, extending longitudinally in a conveying direction and intended to be positioned in such a way as to support lateral sides of the sheet of glass, and the holder comprises at least one holding system placed above the lateral conveying systems and above the sheet of glass and intended to limit an amplitude of the movements of the sheet of glass, wherein the or each holding system is a belt on which are distributed protuberances, and wherein each of the protuberances has a shape that limits contact between the belt and the sheet of glass, at a location of the protuberance, to a point contact.

2. The device as claimed in claim 1, wherein the holder comprises at least two holding systems positioned above and facing the lateral conveying systems and intended to be above the sheet of glass so as to limit the amplitude of the movements of the sheet of glass.

3. The device as claimed in claim 2, wherein the conveyor further comprises at least one central conveying system.

4. The device as claimed in claim 1, wherein the or each holding system is fixed and is not in contact with the sheet of glass.

5. The device as claimed in claim 1, wherein the or each holding system moves at a speed of the sheet of glass and is in contact with the sheet of glass at points of contact or along lines of contact.

6. The device as claimed in claim 1, wherein the protuberances have a height comprised between 5 and 50 mm, and the protuberances are spaced apart by a distance of less than ten times their height.

7. The device as claimed in claim 1, wherein the or each holding system is intended to generate local contact with the sheet of glass.

8. The device as claimed in claim 1, wherein the holding systems have contact surfaces that are made of a polymeric plastics material that carries no risk of scratching the sheet of glass, making it possible to adapt to the local curvature of the sheet of glass without applying too great a reaction force to the sheet of glass.

9. The device as claimed in claim 1, wherein the lateral conveying systems and the holding system are adjustable laterally and heightwise to adapt to the size and curvature of the series of sheets of glass.

10. A washing and drying facility comprising at least one holding device as claimed in claim 1 for cleaning sheets of glass for vehicle glazing.

11. The device as claimed in claim 1, wherein the holder is configured to hold the sheet of glass in a horizontal position.

12. The device as claimed in claim 2, wherein the conveyor comprises two parallel and spaced-apart central conveying systems which are positioned between the lateral conveying systems, the sheet of glass being intended to face the central conveying systems in its central part.

13. The device as claimed in claim 6, wherein the protuberances have a height comprised between 10 and 30 mm, and the protuberances are spaced apart by a distance of less than five times their height.

14. The device as claimed in claim 8, wherein the polymeric plastics material has a Shore D hardness of less than 90.

15. The device as claimed in claim 1, wherein at least one of the protuberances has a shape of a cone, a hemisphere or a pyramid.

16. The device as claimed in claim 1, wherein a contact area between the belt and the sheet of glass defined by the point contact is at most 25 mm.sup.2.

17. The device as claimed in claim 1, wherein a width of the protuberance is less than a width of the belt.

18. A device for conveying and holding a sheet of glass, comprising a conveyor and a holder configured to hold a sheet of glass in position, wherein the conveyor comprises at least two spaced-apart and parallel lateral conveying systems, extending longitudinally in a conveying direction and intended to be positioned in such a way as to support lateral sides of the sheet of glass, and the holder comprises at least one holding system placed above the lateral conveying systems and above the sheet of glass and intended to limit an amplitude of the movements of the sheet of glass, wherein the or each holding system is a wire.

19. The device as claimed in claim 18, wherein the wire has a diameter comprised between 5 and 50 mm.

20. The device as claimed in claim 7, wherein the local contact is in the form of at least one point of contact or at least one line of contact.

21. The device as claimed in claim 20, wherein an area of contact is at most 25 mm.sup.2 or the line of contact has a width of at most 3 mm.

Description

(1) The present invention is now described with the aid of examples which are purely illustrative and do not in any way restrict the scope of the invention, and on the basis of the attached illustrations in which:

(2) FIG. 1 depicts, in a washing facility, a schematic view in cross section of the conveying and holding device of the invention according to a first embodiment in the position of holding a sheet of glass, the view in cross section being a transverse section with respect to the longitudinal direction of conveying and situated in a vertical plane passing through the point of contact of the sheet of glass with the holding systems;

(3) FIG. 2 is a schematic plan view of the conveying and holding device of the invention of FIG. 1;

(4) FIG. 3 depicts, in a washing facility, a schematic view in cross section of the conveying and holding device of the invention according to a second embodiment in the position of holding a sheet of glass, the view in cross section being a transverse section with respect to the longitudinal direction of conveying and situated in a vertical plane passing through the point of contact of the sheet of glass, the holding systems being wires;

(5) FIG. 4 is a schematic view from above of the conveying and holding device of the invention of FIG. 3.

(6) The conveying and holding device 1 of the invention illustrated in FIGS. 1 and 2 or 3 and 4 has the purpose of holding a sheet of glass 2 in a substantially horizontal plane of conveying it or contributing to conveying it in a direction F and of holding it in position without any effect of amplitude or at the very least by minimizing these effects of amplitude when subjected to high vibrations on its two faces, in particular by water and air pressure jets.

(7) FIG. 1 is a schematic illustration in cross section of a conveying and air-spraying facility 3 comprising the conveying and holding device 1 for conveying and holding a sheet of glass 2, comprising two parallel and spaced-apart lateral conveying systems 10A and 10B arranged laterally with respect to the sheet of glass 2, and for preference a central conveyer 4 comprising two drive belts 40 and 41 and positioned between the two lateral conveying systems 10A and 10B and water or air pressure jets symbolized by the arrows F1 and F2 directed vertically respectively upward and downward.

(8) Furthermore, according to the invention, the device comprises holding systems 11A and 11B intended to block the lifting of the sheet of glass when, under the effect of the pressurized water or air jets, it lifts off the lateral conveyors 10A and 10B.

(9) The sheet of glass 2 has two opposite faces, a lower face 20 and an upper face 21, extending horizontally, the lower face 20 faces downward. The sheet of glass comprises two opposite lateral sides 22A and 22B which are parallel to the direction of travel, and two other sides referred to as the upstream side 23A and downstream side 23B, which are transverse to the lateral sides. Conveying is in the direction of the arrow F (FIG. 2).

(10) The sheet of glass 2 rests horizontally on the drive belts 40 and 41 via its edge at its upstream 23A and downstream 23B sides (at least at four points depending on its curvature).

(11) The conveying and holding device 1 guarantees, via the holding systems 11A and 11B, that the sheet of glass 2 is held in this horizontal plane perpendicular to the jets.

(12) The sheet of glass 2 in the example depicted is curved, the lower face 20 corresponding to the concave face 20.

(13) The concavity of the sheet of glass therefore faces downward, which means to say faces the central conveyer 4.

(14) The sheet of glass 2 therefore rests in its middle part via its lower face 20 on the central conveyer 4.

(15) The lateral conveying systems are intended to provide lateral support to the sheet of glass which, because of its curvature, rests at least at one point on its peripheral edge on each lateral conveyor. In practice, because of its self-weight and flexibility, the glass usually deforms enough for this support to be at two, upstream and downstream, points on each lateral conveyor.

(16) When the holding systems are in contact with the glass, this contact is at two point P1 and P2 as illustrated in FIG. 1.

(17) The conveying systems 10A and 10B with their holding systems 11A and 11B are positioned by adjusting the holding elements before the start of the production run (the washing of sheets of glass), so as to support the shapes of sheets of glass (generally for windshields) of the coming production run.

(18) The holding systems 11A and 11B are able to be adjusted in terms of position in a horizontal plane perpendicular to the axis of travel of the sheet of glass.

(19) The holding systems 11A and 11B are, for example, belts.

(20) For preference, the holding systems (such as belts) comprise protuberances 12 which constitute (localized) points of contact with the glass when the sheet of glass touches said holding systems.

(21) The material of which the holding elements (protuberances) pressed against the glass are made is tailored to avoid the creation of rupture initiators when the glass experiences vibrations due to washing and to drying.

(22) The protuberances which are made of a plastics material of the polymer type which does not risk scratching the glass, for example with a Shore D hardness of less than 90 and soft enough, for example being made of soft rubber, or in particular of a Shore A hardness comprised between 20 and 80, making it possible to adapt to suit the local curvature of the glass without exerting too great a reaction force on the glass.

(23) The protuberances on the holding belt are evenly distributed so that there is no possible contact between the sheet of glass and the belt. In practice, the protuberances have a height comprised between 5 and 50 mm, for preference between 10 and 30 mm, and the protuberances are spaced apart by a distance of less than ten times their height, for preference less than five times their height.

(24) The protuberances 12 are derived for example from notched surfaces or waves affording an alternation of ribs (protuberances) and voids which are parallel. The protuberances may have various geometries, such as pyramids the tops of which may or may not be truncated, spheres, hemispheres or other shapes.

(25) FIGS. 3 and 4 correspond to an alternative form of embodiment of FIGS. 1 and 2. The holding systems here take the form of wires 13A and 13B.

(26) The wires 13A and 13B limit the contact with the sheet of glass to lines of contact. In the case of a wire, the wire will be smooth and because its diameter is small, contact between the wire and the sheet of glass will be limited to a line of contact the position of which will oscillate under the effect of the water and air jets, allowing the entire surface to be cleaned.

(27) The wire has a diameter comprised between 5 and 50 mm, in particular between 10 and 30 mm.