[0001] The present invention relates to a guiding belt particularly for moving flexible
sliding doors.
[0002] As is known, in many civil and industrial fields, flexible sliding doors are used
which are substantially provided by means of a sheet-like element made of flexible
plastic material, which is made to slide by way of guides provided in the jambs of
the openings on which the doors are arranged.
[0003] Means for engaging the actuation system are currently provided at the longitudinal
edges of flexible sliding doors; such means are generally constituted by a longitudinal
strand of steel to which a plurality of spaced blocks are connected, forming in practice
a rack element for coupling to a gear or sprocket that moves the door.
[0004] This embodiment suffers currently considerable problems, the first of which arises
from the fact that it is necessary to fix each block individually to the sheet-like
element that constitutes the door, accordingly entailing particularly long installation
times.
[0005] Another problem is further constituted by the fact that if such blocks are accidentally
extracted from the sliding guide, considerable difficulties are encountered in restoring
the correct arrangement.
[0006] Furthermore, fixing of the individual blocks can cause uneven effects and therefore
optimum meshing with the driving gear is not achieved.
[0007] The aim of the invention is to eliminate the drawbacks noted above by providing a
guiding belt, particularly for moving flexible sliding doors, which can be connected
to the door very rapidly and simply, at the same time obtaining an element that is
extended continuously without discontinuities, so that its connection to the door
is facilitated considerably and also improved mechanically.
[0008] Within this aim, an object of the invention is to provide a guiding belt that allows
to always achieve improved sliding characteristics and further allows easy and rapid
reinsertion in the guides if the guiding belt accidentally escapes from the guides.
[0009] Another object of the present invention is to provide a guiding belt that thanks
to its particular constructive characteristics is capable of giving the greatest assurances
of reliability and safety in use.
[0010] Another object of the present invention is to provide a guiding belt particularly
for moving flexible sliding doors that can be obtained easily starting from commonly
commercially available elements and materials and is also competitive from a merely
economical standpoint.
[0011] This aim and these and other objects that will become better apparent hereinafter
are achieved by a guiding belt particularly for moving flexible sliding doors, characterized
in that it comprises, on at least one side of a supporting belt, a layered protruding
belt that can slidingly engage the guide of a flexible and sliding door and the like,
said supporting belt being rigidly associable with a longitudinal edge of said flexible
sliding door, means for engaging means for moving said sliding door being further
provided on said guiding belt.
[0012] Further characteristics and advantages of the present invention will become better
apparent from the following description of a preferred but not exclusive embodiment
of a guiding belt particularly for moving flexible sliding doors, illustrated by way
of non-limiting example in the accompanying drawings, wherein:
Figure 1 is a perspective view of a guiding belt according to the invention connected
to the longitudinal edges of a sliding door;
Figure 2 is a perspective view of a detail of the guiding belt according to the invention;
Figure 3 is a perspective view of a detail of the guiding belt connected to a door;
Figure 4 is a sectional view, taken along a horizontal plane, of the guiding belt
within the guide arranged on the jamb of a door and the like;
Figure 5 is a schematic view of the means for moving the sliding door;
Figure 6 is a schematic view of the apparatus for producing the guiding belt according
to the invention.
[0013] With reference to the figures, the guiding belt particularly for moving flexible
sliding doors according to the invention, generally designated by the reference numeral
1, comprises a supporting belt 2, which is advantageously made of a material that
is chemically compatible with the material of a sliding door 3 and can therefore be
constituted by polyester fiber fabric or other material impregnated with PVC thermoplastic
resin or the like.
[0014] Protruding belts 10 are provided on at least one side and preferably both sides of
the supporting belt 2 and are advantageously made of various layers of polyester fiber
fabric or the like.
[0015] In greater detail, the protruding belts 10 are provided by means of a base belt 11
that is chemically compatible with the supporting belt, so as to facilitate bonding.
[0016] Preferably, the base belt 11 is made of a copolyamide that is compatible with the
PVC of the supporting belt.
[0017] A reinforcement layer 12 of glass fabric is provided on the base belt 11, and layers
of fabric 13, advantageously made of polyester and impregnated with thermosetting
epoxy resin, like the reinforcement layer 12, are superimposed on said reinforcement
layer 12.
[0018] The polyester fabric is constituted, both in the weft and in the warp, by a highly
twisted multifilament yam with 500 to 3000 twists per meter, so as to obtain a flexible
fabric.
[0019] Both the polyester fabric and the glass fabric are then impregnated with a thermosetting
resin that has a quantity of resin equal to 30-60% of the total weight of the preimpregnated
material.
[0020] The impregnation resin is formed by means of a basic thermosetting resin, such as
epoxy resin or the like, to which a flexibilizing additive, such as rubber, is added
in a proportion comprised between 10 and 30% of the total.
[0021] Advantageously, the layering of each protruding belt is provided so as to obtain
a longitudinal recess that affects both sides of the guiding belt.
[0022] Once the three belts, i.e., the supporting belt and the two protruding belts correspondingly
provided on both sides of the supporting belt, have been coupled, a blanking step
is performed which provides holes, designated by the reference numeral 25, which in
practice form a rack that constitutes the means for engaging the means for moving
the flexible door, which are constituted for example by a pinion 26, which is motorized
in any manner so as to produce sliding.
[0023] The assembly is completed by providing an outer covering layer made of polytetrafluoroethylene,
designated by the reference numeral 30, which allows to make the outer surfaces slippery,
thus allowing optimum sliding in the guides 35 and facilitating the reinsertion of
the belt if it escapes from the guides.
[0024] To provide the guiding belt, it is possible to use an apparatus of the type shown
in Figure 6, which substantially has a unit 40 for feeding the base belt 2, on the
opposite sides of which units 41 for feeding the two protruding belts 10 are provided.
[0025] The belts 2 and 10 are inserted within a hot die 42 with a temperature level that
allows to melt both the base belt 11 of the protruding belt 10 and the thermoplastic
matrix of the supporting belt 2.
[0026] Downstream of the hot region 42 of the die there is a cold region 43 in which bonding
is produced in practice.
[0027] The polytetrafluoroethylene belt is then applied in the region 44; this is followed
by a blanking region 45, where the openings are provided.
[0028] Advantageously, the polyester fabric that is used to form the various layers has
a surface weight comprised between 50 and 120 g/m
2 and the layer of glass fabric has a weight comprised between 150 and 250 g/m
2.
[0029] From what has been described above it is thus evident that the invention achieves
the proposed aim and objects, and in particular it is stressed that a guiding belt
is provided which is flexible and continuous and can be rigidly coupled at the longitudinal
edges of a flexible door, so as to provide an element that allows to move the door
very easily and safely, together with the fact that it can be applied particularly
rapidly, by utilizing the characteristic that the supporting belt is chemically compatible
with the material that constitutes the door and accordingly allows to obtain optimum
bonding.
[0030] Furthermore, the provision of a continuous belt allows to adapt without any problem
to the various dimensions that are used, always obtaining an assembly that is stable
and monolithic.
[0031] Furthermore, the particular shape of the protruding belts, in addition to being guided
in engagement with the movement means, also allows the possibility to easily reenter
the guide 35 arranged on the jambs if accidental uncoupling occurs.
[0032] The invention thus conceived is susceptible of numerous modifications and variations,
all of which are within the scope of the appended claims.
[0033] All the details may further be replaced with other technically equivalent elements.
[0034] In practice, the materials used, as well as the contingent shapes and dimensions,
may be any according to requirements. The disclosures in Italian Patent Application
No. MI2003A000536 from which this application claims priority are incorporated herein
by reference.
[0035] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A guiding belt particularly for moving flexible sliding doors, characterized in that it comprises, on at least one side of a supporting belt, a layered protruding belt
that can slidingly engage the guide of a flexible sliding door and the like, said
supporting belt being rigidly associable with a longitudinal edge of said flexible
sliding door, means for engaging means for moving said sliding door being further
provided on said guiding belt.
2. The guiding belt according to claim 1, characterized in that it comprises one of said protruding belts on each side of said supporting belts.
3. The guiding belt according to the preceding claims, characterized in that said supporting belt is formed by a plurality of layers of polyester fabric.
4. The guiding belt according to one or more of the preceding claims, characterized in that said protruding belt comprises a base belt that is chemically compatible with said
supporting belt, a reinforcement layer made of glass fabric being provided on said
base belt, a plurality of layers of polyester fiber fabric being arranged on said
reinforcement layer.
5. The guiding belt according to one or more of the preceding claims, characterized in that said reinforcement layer and said fabric layers are impregnated with a thermosetting
resin with the addition of a flexibilizing additive.
6. The guiding belt according to one or more of the preceding claims, characterized in that said thermosetting resin is provided in an amount comprised between 30 and 60% of
the total weight of the preimpregnated material.
7. The guiding belt according to one or more of the preceding claims, characterized in that said flexibilizing additive is comprised in an amount between 10 and 30% of the total.
8. The guiding belt according to one or more of the preceding claims, characterized in that said flexibilizing additive is constituted by rubber.
9. The guiding belt according to one or more of the preceding claims, characterized in that it comprises a longitudinal recess on said at least one protruding belt.
10. The guiding belt according to one or more of the preceding claims, characterized in that said base belt is chemically compatible with said supporting belt in order to facilitate
its bonding.
11. The guiding belt according to one or more of the preceding claims, characterized in that said supporting belt is chemically compatible with the material that provides the
sheet-like element that constitutes said flexible sliding door.
12. The guiding belt according to one or more of the preceding claims, characterized in that said engagement means are constituted by perforations provided in said base belts
and said supporting belt at said recess.
13. The guiding belt according to one or more of the preceding claims, characterized in that it comprises an outer coating layer made of polytetrafluoroethylene that affects
said protruding belt.
14. The guiding belt according to one or more of the preceding claims, characterized in that the layer of polyester fabric is obtained, both in the weft and in the warp, by means
of a multifilament yam with 500-3000 twists per meter.
15. The guiding belt according to one or more of the preceding claims, characterized in that said layer of polyester fabric has a weight between 50 and 120 g/m2.
16. The guiding belt according to one or more of the preceding claims, characterized in that said glass fiber layer has a weight comprised between 150 and 250 g/m2.