AU492995B2 - Manufacture of laminates - Google Patents

Description

83 89

The invention relates to apparatus for tporarily

or permanently assembling sheets of glass withj of

of the plastics material to form a laminate in which a stack provided, superposed sheets are passed between rollers which are of the over an axial length corresponding to at least the width of which sheets to be assembled, with a hollow elastic envelope,

the internal space is provided with a fluid under pressure.

In French Patent 1,120,145 there is described a device

of this type. The rollers are ormdof hollow cylinders of

steel provided with holeson i there is mounted a layer of

rubber, theed parts of this layer projecting outside the

ends of theisteel cylinderS. The projecting parts of this

are connected in airtight manner to an elastic envelope

by intermediate pieces of annular shape. The space formed

between the steel cylinder and elastic

envelope is maintained under pneumatic pressure.

Rollers of this type have been suggested for laminating

flat sheets of glass or cylindrically curved sheets. However

the windscreens of automobiles which form an important

proportion of the laminated panes which are currently

manufactured generally have a spherical curvature which is more

or less large. It is not possible to treat them in cylindrical

press rollers such as those mentioned above.

According to the present invention, there is provided

apparatusA laminates of glass sheets with sheets

of plastics material,1 a air of rollers between

which superposed sheets to be laminated may be passed, each

roller a drum which is surrounded over at least a

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83892n5 portion of its length by a hollow elastic inflatable

envelope the edges of which are secured to rims mounted on the

drum, the maximum axial length of the inflated envelope

being greater than -the separation between the rims

a least one rim being movable axially along the drum.

The elastic envelope allows modification of the shape

of the rollers to handle both planar sheets and sheets

having curvature in one or two dimensions.

The envelopes may have a very elastic structure even

at their ends because they do not have in these regions any

hard member or irregularity. Owing to this feature and

because of the movement which is possible for one of the

rims, the shape of the envelope may be modified between wide

limits to the shape of the sheets to be assembled so that

their flexibility of application is much greater than that

of already known rollers.

Because of the great elasticity of the rollers even

in the region of the ends and from the fact that the equal

pressure is exerted by the rollers, the apparatus is

suitable for pressing articles of glass/plastics material

laminates in which one or several layers of plastics material

are applied to a side of a monolithic or laminated pane.

The manufacture of such laminated articles is

especially difficult when it is desired to obtain a pane

free from optical faults, as is the case for example for

windscreens of vehicles. None of the structures of

pressing rollers previously known have allowed obtention

of a satisfactory pressing in this regard. The degassing

and pressing of such laminated articles has been carried

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out up to the present, exclusively by treatment under vacuum

or, before the treatment under pressure, it has been necessary

to apply to the sheet of plastics material a protective layer

such as a glass sheet which has to be eliminated at the end

of pressing. The two processes are very costly. The use of

the protective sheet has the further disadvantage that separat-

ion of thelaminated article in the finished state from the

protective sheet presents great difficulties.

It has been found that using the apparatus of the present

invention the rollers can exercise a pressure so regular, even

in the end regions of the roller, that they may be used with

good results for application of layers of plastics material to

planar or curved planes. The diameter of the rollers is pref-

erably at least 30cm and suitably in the range 40 to 80cmA Sthe envelope is inflated, it is thus possible to carry out

not only temporary assembly of glass laminates, but also the

final adhesion of the laminated article. This represents an

important simplification in the manufacture of such articles.

The structure of the envelope may resemble that of a vehicle

pneumatic tyre, that is to say comprise a structure known as

a "carcass" covered with a layer of natural or synthetic rubber.

The surface of the rubber iser may have a slight roughness;

good results are obtained when the depth of the indentations

of the coating is from 50 to 200 jAm. The envelope may be

inflated by compressed gas, such as air, or with a liquid such

as water. Preferably the pressure exerted within the envelope

is adjustable.

An embodiment of the invention will be described by

way of Example with reference to the accompanying drawings,

in which: 4, 492995 of a device Figure 1 shows a frontal elevation according to the invention; the same device; Figure 2 is a side elevation of 1; Figure 3 is a section of part of Figure a larger scale. Figure 4 is a detail of Figure 3 on rollers Referring to Figure 1, a housing supporting 1 and 2, a transverse is formed by vertical support members base 3 and an upper cross piece 4. rollers 5 and 6. In the frame is mounted a pair of rotation in bearings 9 The lower roller 5 is mounted for 7 and 8, the bearings 9 and and 10 by means of half shafts 1 of the support. being fixed on the mountings 2 and similar fashion by half The upper roller 6 is mounted in and 16. The bearings 15 and shafts 13 and 14 on bearings 15 end of piston rods 17 and 16 are themselves mounted at the that the roller 6 may be 18 activated by jacks 19 and 20 so of the jacks. The fluid lifted or lowered under the action by ducts 21 under pressure is fed to the jacks the position and 22. In order to fix in a precise manner abutments 23 and 24 of the roller 6 there are provided 25 and 26. screwed in adjustable manner on brackets motor 30 by means The lower roller 5 is driven from 32, 33- A transmission of sprocket wheels and chain 31, generally necessary. for driving the upper roller is not one against the other The two rollers are strongly pressed between them so even in the absence of a stack of sheets by rotation of the lower that the upper roller 6 is driven roller

492.995 for The half shafts 8 and 14 are hollow and serve the envelopes introduction of fluid under pressure into of the rollers. Connection between the duct under pressure shafts 8 and 14 is effected by rotating 38 and the half joints 36 and 37. Figure 2 it will be seen that there is provided In of and beyond thie rollers a train of support in front rollers such as 43 and 4 1 mounted on a frame 40, 41, 42 in of sheets 45 to be order to facilitate transport of a stack passed between the rollers. In the case of pressing of of support rollers is curved sheets of glass the train adapted by its curvature or shape to the shape of the glass is sheets. The structure of the upper roller 6 which to that of the lower roller 5 is shown in Figures identical is formed by cylindrical drum 48 of 3 and 4. Each roller diameter 25 to 40 cm which The envelope 49 forms carries an envelope 49 for the roller. fluid under pressure. with the drum 48 a cavity 50 filled with

49 has an exterior diameter of about 60 cm and The envelope

the axial direction of the drum 48 a length of presents in

about 1 m so that glass panes of conventional size and shape dimensions by may be engaged over the whole of one of their

the rollers. The thickness of the elastic envelope in the

The structure of this peripheral region is from 3 to 5 mm. of a envelope 49 corresponds to some extent to that is pneumatic tyre. At the base 51 of the envelope there

cord 52 about which there is rolled several provided a steel

thicknesses of tissue which forms the "carcass" of the

envelope. The carcass supports an intermediate structure

492.995 by an which isL tissue~which is covered in turn rubber. There have upper layer of natural or synthetic natural rubber having the been obtained good results with Shore hardness 680, modulus of following characteristics: be elasticity E 29 kg/cm The upper layer of rubber may adhesion of layers forming slightly rough in order to avoid this depth of the hollows forming the pane on the roller, the 200 ,um. It is also possible to roughness may be from 50 to to facilitate, when necessary, provide a certain roughness in powder form such as talc. the use of a lubricating agent to press between the In the case where it is necessary necessary small movements of rollers spherical panes the are facilitated by use of the panes relative to the rollers such a lubricating agent. structure and the layer The carcass, the intermediate of the rollers shouldkbe as forming the elastic envelope is to say without local homogeneous as possible, that composition of material, in differences in thickness and on the stack to be pressed. order to obtain a uniform pressure onto At one end of the drum 48 the rim 72 is welded rim 53 is the drum. At the other end of the drum the This sliding serves not capable of sliding on the drum. the envelope 49 on the drum only to facilitate mounting of the rim 53, modification of the but it allows, by sliding of is more or less balloon-like. shape of the envelope 49 which may be adapted between Thus the shape of the envelope of curved pane to be certain limits to different shapes 54 treated. The rim 53 forms, owing to an extension directed outwardly, a groove 55 with the exterior surface

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83892/75 of the drum. In this annular groove there is placed a

compressible ring 56. The flange 57 which is mounted in

position on the drum by the screw 58 compresses the ring 56.

The half shafts 13 and 14 are connected to the drum 48 by

stuffing 61 and ring 62. The half shaft 14 is hollow in

order to allow passage of the fluid under pressure. The

duct for fluid under pressure 63 connects the hollow half

shaft 14 with the internal space 50 of the envelope.

It has been found that there are obtained excellent

results when the pressure in the rollers is of the order of

to 2 atmospheres gauge, and that even at high pressures

there are exerted compressive forces which are extremely

uniform and thus avoid the unfavourable effects on stacks to

be laminated.

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Claims (1)

1. 8 3 8 9.2 175

   The Claims defining the invention are as follows:

   1. Apparatus' laminates of glass

   materialli sheets with sheets of plastics to be pair of rollers between which superposed sheets a drum which laminated may be passed, each rolleri its length by a is surrounded over at least a portion of

   hollow elastic inflatable envelope the edges of which are

   maximum axial secured to rims mounted on the drum, the greater than length of the inflated envelope beinc

   the separation betweendt he rimnska44 at least one rim being

   movable axially along the drum.

   the 2. Apparatus according to Claim 1, in which the drum, a groove rim which is movable forms, together with

   containing a compressible ring which is pressed against

   be fixed at the drum and the rim by a flange which may

   different positions on the drum.

   C&iM in which 3. Apparatus according to Claim 1 or42, at least 30 cmAW4 the rollers have a diameter of

   4. Apparatus according to Claim 3, in which the

   rollers have a diameter from 40 to 80 cm,-

   Claims 1 to 4, Apparatus according to any one of having an in which the envelope is formed of a carcass

   outer layer of natural or synthetic rubber.

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   83892/5im 6. Apparatus according to Claim 5, in which the

   surface of the outer layer has reliefs or indents to

   provide a rough surface.

   7. Apparatus according to Claim 6, in which the

   reliefs or indents have a height from 50 to 200 um.

   8. Apparatus according to any one of Claims 1 to 7,

   provided with means for supplying air under pressure to the

   interior of the envelope.

   9. Apparatus according to any one of Claims 1 to 7,

   provided with means for supplying a liquid under pressure

   to the interior of the envelope.

   Apparatus according to any dreceding claims, in which the pressure exerted within the envelope is adjustable.

   11. Apparatus according to Claim 1, substantially as

   hereinbefore described with reference to the accompanying

   drawings.

   12. Laina te s when assembled by means oi apparatus

   according to any4receding claimS.

   DATED this 11th day of August, 1975. SAINT-GOBAIN INDUSTRIES by its Patent Attorneys; ®r CALLINAN AND ASSOCIATES.

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