FR2482901A1 - Press for quilted covering for furniture - has toggle link operated heated upper platen to press material onto thermo-welding lower platen - Google Patents

Abstract

The press comprises a lower platen, equipped with the tools for thermo-welding the material in accordance with the quilted pattern. The material combines a plastic foam padding bonded to the required surface covering; this is laid onto the lower platen tools, being held by suction. An upper platen descends onto the material, to apply pressure and complete the thermo-welding process. This upper platen is heated and is operated by a dual toggle link mechanism connected to a power cylinder. The thermo-welding tools move a short distance upwards to impress the pattern.

Description

 The present invention relates to a machine for forming plies of synthetic material, in particular multiple plies, and in particular a machine intended to produce products in the form of plies or sheets, composed of several plies, at least some of which are made of susoeptible plastics. to be heat sealed, in particular to make padded sheets.

 To heat seal several layers on top of each other, presses are used which must exert significant forces. However, known heating presses have plates controlled by power jacks performing a large stroke. However, such jacks are not only very comatose but also of relatively slow operation; they require a powerful hydraulic installation.

 In some cases, it is possible to use high frequency welding presses which are lighter.

However, high frequency heat sealing cannot be applied to all plastics.

 The object of the present invention is to create a heat-bonding or heat-sealing machine which makes it possible in particular to produce padded sheets, with simple, rapid means, of an inexpensive production and maintenance.

To this end, the invention relates to a machine characterized in that it comprises - a first plate performing a large opening stroke
and closing, - a second plate carrying out a small opening stroke
and closing, to act in compression, - displacement members controlling the movement of the first
plate, - compression members controlling the closing movement
of the second plate, the second plate carrying forming tools D being movable
between a working position opposite the first plate
for compression and a clear position relative to the
first plate, this plate being provided with means of transat tion, capable of being retracted when the plate is in the working position opposite the first plate, in order to occupy a floating position and to follow the movement of approach and compression of the two plates.

 As one of the plates performs a large stroke to close the gap between the plates, the interval necessary for the introduction and extraction of the products, and the other plate performs the compression stroke, cylinders are avoided of power which must have a great stroke. This not only makes it possible to reduce in particular the cost of the installation, but also to reduce the time of the work cycle and consequently to increase the efficiency of the machine.

 According to another characteristic, a suction means is connected to the cavities of the tool X to create a depression there.

 This suction at the tool has multiple advantages because, while allowing the evacuation of harmful or dangerous gases emitted during heat sealing, it deforms the layers of the complex before heat sealing. A product is thus obtained having an asymmetrical structure corresponding to a conventional padded sheet which would be cut along its median plane. Indeed thanks to the deformation of the sheets before their heat-sealing carried out at least at the "seams" of the padding, the rear surface of the product remains flat; the upholstery does not tend to come out from the rear side. This allows a significant saving of filling material of the upholstery.

 Another advantage of the vacuum exists at the opening of the mold: the product remains on the plate carrying the tool and is detached from the other smooth plate which is heating.

The characteristics according to which on the one hand the plate carrying the tools can enter and leave the machine and on the other hand the smooth plate is heated has in particular the following advantages - the tools can be changed easily; besides they are
simply placed on the second shelf. The tool placed on the pla
teau can be composed of several distinct parts.

- the installation of the tablecloths is simple.

- under the effect of their weight, the sheets tend to collapse
into the mold cavities and take the form of padding
by acting in the same direction as the aspiration.

- the hottest surface during heat sealing is on
back of the manufactured product. This allows to use for
the front side is the visible side, more
fragile.

- it is easier and less expensive to fill the tray
smoother a non-stick layer than doing it on
tools all the more since the tools are numerous in function
decorative patterns to make etc.

The present invention will be described in more detail using an embodiment shown schematically in the accompanying drawings in which
FIG. 1 is a section through a machine according to the invention,
- Figure 2 is a section of a detail of the machine of Figure 1
FIG. 3 is a layout diagram of the machine and of the supply and output devices, for discontinuous operation,
- Figure 4 is a layout diagram of the machine and the feed devices for continuous operation.

 According to FIG. 1, the machine for shaping and heat sealing a complex with several layers consists of a frame carrying a first plate or upper plate 2 and a second plate or lower plate 3. These plates 2, 3 are placed ltun next to each other and in their interval, they receive the stacking of several layers, to compress and heat seal them according to surfaces or decorative or functional lines.

 The upper plate 2 is connected to the frame by displacement members 4 constituted by toggle levers 41, 42 articulated on the one hand to the frame 1 and on the other hand, to the plate 2. The articulated connection 43 between the two levers 41 , 42 respectively is also connected to a rod 5 controlled by a jack 6. The movement of the rod 5 in the direction of arrow A causes the movement of lowering or raising of the plate 2 in the direction of arrow B.

 The members 4 forming toggle joints can switch between a lifting position in which the two arms 41, 42 define a relatively closed angle and a lowering position (not shown) in which the rod 5 has moved sufficiently to the right. , according to the figure, to bring the two arms 41, 42 in alignment with one another or even beyond the vertical XX passing through the point of articulation of the lever 41 to the frame 1.

 Such positioning is important for the compression phase.

 In fact, when the plate 2 is completely lowered, the arms 41, 42 are practically aligned with respect to each other so that the compression force acting in the vertical direction, and which is transmitted by the arms 41, 42 in b ti 1, results in only a very small component, or even zero, in the direction of the rod 5 so that the component repercussion on the cylinder 6 during the compression phase is extremely small.

 If, according to a variant suggested above, the arms 41, 42 tilt to the right of the vertical passing through the articulation of the arms 41 to the frame 1, and there is an angular stop integrated in the articulation 43, this stop absorbs the compression forces so that no compression force is then passed on to the jack 6.

 The second plate or lower plate 3 consists of a boot 31, parallelepiped, the upper surface of which is provided with perforations 32. This boot is connected to an air suction circuit shown diagrammatically by the fan 7.

 The plate 3 rests on rollers 33 rolling on rails 8 integral with the frame 1. On its upper surface, that is to say the surface provided with the perforations 32, the casing 31 carries the tool 9 used for compression and heat sealing .

This tool 9 is composed by an assembly of vertical blades 91 arranged on edge and whose trace in the horizontal plane corresponds to the drawings to be made by heat sealing. The tool 9 is thus presented as a non-closed grid placed on the upper surface of the shoemaker 31, so as to communicate through the orifices 32 with the interior of the shoemaker 31.

 The complex of layers to be heat-sealed 10 is placed above the tool 9. In FIG. 1, the suspended shape, which the material of the layers of the complex 10 takes, is shown diagrammatically in the interval between the blades 91 of the molding tool 9.

 The rollers 33 which roll on the horizontal rails 8 make it possible to bring the plate 3 with its tool 8 either to the interior of the machine, under the location of the upper plate 2 for the compression and heat-sealing operations or to the exterior of the machine, leaving clear the upper surface of the tool 9 for the establishment of the complex 10 or its removal, after treatment.

The rollers 33 carried by arms controlled by a jack (not shown) are retractable in the thermo position
welding so that the plate 3 is floating on the cylinders
compression.

The compression cylinders 11 which act on the plate 3 are power cylinders, with short stroke. These cylinders
are supplied from the hydraulic unit 12.

To facilitate the movement of the plate 3 relative
to the jack 11 and to avoid, at the same time, that compression forces are exerted on the rollers 33 and consequently on the rails 8 when the plate 3 is in the compression position, the rollers 33 are retractable (not shown); the rollers rise slightly so that the plate 3 no longer rests on the jacks 11 during the compression movement at short stroke.

Although in theory, such a measure is not necessary, since the jacks 11 raise the plate 3 when it is above them, it is nevertheless advantageous, in practice, to have a relatively large clearance
both between the lower surface of the plate 3 and the upper surface of the jacks 11. However, to have this clearance, it is necessary that after the compression phase, when the upper plate 2 is raised, one can also raise the lower plate 3 to release it from the cylinders 11.

 The lower surface of the plate 2 is constituted by a non-stick layer at the working temperatures of the machine, to prevent the layers of the complex 10 from sticking.

 To simplify the structure of the machines, the upper plate 2 carries the heating means necessary for heat sealing.

 This solution offers the advantage that the hottest part of the compression plates is the upper plate 2, that is to say the one which corresponds to the rear face of the products.

 Another advantage of this solution is that the inner surface of the plate 2 is perfectly smooth so that the complex 10, obtained, has an asymmetrical structure O the raised parts are those facing the tool 9, ceestnå- say the visible side of the product while the rear side is relatively smooth. This allows a saving of half of the padding means ensuring the swelling of the complex 10 between the heat-sealing lines (expanded synthetic material...).

The machine, described in Figure 1, works as follows
After setting up a complex of heat-sealable plies on the tool 9 of the plate 3 in the disengaged position, the plate is automatically pushed back manually inside the machine, to put it in the working position under the plate 2.

 The machine can then start its working cycle by retracting the rollers 33 and lowering the upper plate 2, then controlling the lifting of the lower plate 3 to compress the complex. During this compression phase, the upper plate 2 remains stationary, the compression forces being essentially provided by the jacks 11.

 Before the compression phase, as soon as the plate 3 is in place inside the machine, the fan 7 creates a depression inside the boot formed by the lower plate 3. This depression is communicated by the orifices 3 to the cavities delimited by the blades 91 of the tool 9. This depression has the following roles in particular - it sucks up some of the layers of the complex 10 inside the cavities to accentuate the swelling of the complex inside the mold, before heat sealing, that is to say blocking of the assembly, - during heat sealing, this vacuum evacuates dangerous or toxic vapors, of partial or total decomposition of the material under the effect of the heat of heat sealing.

 - The vacuum retains the complex 10 on the mold 9 after the thermoforming cycle, during the lifting of the upper plate 2. This prevents the complex from clinging to the plate 2 and considerably complicates the extraction of the product from the machine.

 After raising the upper plate 2 and replacing the rollers 33, the lower plate 3 can be automatically or manually removed from the machine to remove the complex 10 and put in place a new complex to be heat sealed.

 According to Figure 2, which shows a section of the lower plate 3 and the upper plate 2 in the working position, the upper plate 2 consists of a non-stick layer 21 facing the complex 10 and a support plate 22 to hold the non-stick surface 21.

 The detail of the lower plate 3 shows the arrangement of the orifices 32 as well as the shape of the plies on the blades 91 of the tool 9.

 In FIG. 2, the deformation of the lower layer 101 as well as of the padding layer 102 of the complex 10 has been exaggerated, inside a cavity delimited by the cutting blades 91 in the mold 9.

 To have a heat-sealed complex 9, having the appearance of a padding, it is not necessary for the fabric or more generally the outer ply 101 to be integral over its entire surface with the inner ply or padding ply 102.

However, in certain cases, for example when the complex 10 is subjected to a very significant wear, for example when this padded complex is used as a covering for the seat, for the backrest, etc. subject to significant shearing forces, it is it is advantageous to have a slight heat seal between the plies 101, 102 without, however, this heat seal not resulting in a crushing of the complex similar to that produced by the heat seal in line with the blades 91.

 According to the invention, to achieve this slight heat sealing, there is housed inside the mold cavities, a sheet 13, permeable to air, of adequate thickness chosen according to the nature of the complex 10 and the effect upholstery to achieve.

 It is also conceivable to reduce the height of the blades 91 so that the plies come to apply to the bottom of the cavities. However, this solution has drawbacks compared to the previous one. In fact, the height of the upholstery may not be uniform: in this case, there are plies 13 of different height in the various cavities of the mold 9.

In addition, the ply 13 distributes the air suction over the entire bottom of the cavity without blocking the orifices 32. This makes it possible to reduce the number of orifices 32. Otherwise, with blades 91 which are not high enough, the ply 101 could plug the holes 32 and block the suction of harmful vapors.

 During compression, the elastic layer 13 exerts a certain pressure on the lower ply 101 to apply it against the corresponding surface of the padding ply 102 and cause a surface heat seal.

 The machine described above allows different variants and adaptations.

 According to a variant of the invention, the lower plate 3 of Figure 1 is made in two parts, one of which is movable and the other is fixed in horizontal translation to lighten the weight of the movable part, leaving the machine .

 According to one of the variants, it is thus possible to fix the tool 9 directly on retractable rollers 33, leaving the case 31 secured to the jacks 11.

 Another solution consists in subdividing the case 31 into two parts, lBune serving as a support for the tool 9 during its movements of horizontal translation between the position inside the machine # and the position outside the machine, and to leave in place inside the machine the elements of the plate 3 which ensure the mechanical strength of the plate and of the tool during the compression phase.

 FIG. 3 shows a layout diagram of a manufacturing installation produced using the machine ioe, described above.

 In the layout diagram of FIG. 3, the machine 100 is not in alignment with the feed table 101 and the outlet table 102.

 The feed table 101 receives the complex A constituted by the continuous sheets not yet cut to the appropriate size.

 These continuous plies coming from rolls not shown are advanced mechanically or by the user, who cuts them using a transverse cutting device 103, to obtain the cut complex B with adequate dimensions.

 Then the complex B is placed on the mold 9 of the lower plate 3 in the extended position. The plate 9 is slid into the machine represented by its b ti 1 for the heat-sealing operation. At the end of the work cycle, the tray 3 is removed and the user removes the complex to put it in the outlet station 102.

 FIG. 3 shows a diagram of an installation carried out using the machine 100, for continuous work, the heat sealing operation remaining discontinuous.

 For this, the scrolling of the complex A is parallel to the rails of the tray 3. The complex live on an entry table 104, in superimposed layers then it passes over the tray 3. The complex is then entered # born at the same time as the plate 3 inside the machine 10 for undergoes the heat sealing operation. At the end of this operation, after the spacing of the plates, the complex A is blocked so that it cannot move, the plate 3 is brought back to resume a new length of the sheet at the level of the station. food 104.

 Generally, depending on the nature of the complexes to be produced, an installation with a discontinuous or continuous supply will be used.

Claims (10)

 10) Machine for shaping and heat sealing a complex with several layers, machine comprising two plates, at least one of which is heated, and which act by compression of the complex for the heat seal machine, characterized in that it comprises - a first plate (2) performing a large opening stroke  and closing, - a second plate (3) carrying out a small opening stroke  and closing, to act in compression, - organs (41, 42, 43,  6) of displacement commanding the  movement of the first plate (2), - compression members (11) controlling the movement of  closing the second plate (3) - the second plate 3 carrying forming tools (9) being  movable between a working position opposite the first  plate (2) for compression and a position released by  relative to the first plate (2), this plate (3) being provided with  translation means, capable of being retracted when the  plate (3) is in working position opposite the first  platform, to occupy a floating position and follow the  movement of bringing together and compressing the two plates  (2, 3).  20) Machine according to claim 1 characterized in that it comprises a suction means (7) connected to the cavities of the tool (9) to create a depression there.  30) Machine according to claim 1, characterized in that the members for controlling the movement of the first plate (2) are double arms (41, 42, 43) forming a toggle joint, one end being connected to the first plate (2 ), the other to the frame (1); the articulation point (43) is connected to a control cylinder (5, 6).  40) Machine according to claim 1, characterized in that the control members (11) for compression of the second plate (3) are power cylinders with short stroke.  50) Machine according to claim 1, characterized in that the sliding plate is mounted on rollers (33) rolling on rails (8), the rollers st retracting in the working position to leave the plate (3) in floating position in look of the first plate (2).  60) Machine according to claim 5, characterized in that the rollers of the plate (3) are carried by pivoting arms controlled by a jack.  70) Machine according to claim 1, characterized in that the second plate (3) is composed of a part remaining in the working position opposite the first plate (2) and a sliding part carrying the tool (9) and being able come in the unobstructed position for loading and unloading the heat-sealed sheets.  80) Machine according to claim 7, characterized in that the plates are arranged one under the other, the first plate (2) being the upper plate and the second (3) the lower plate.  90) Machine according to claim 1 characterized in that the plate (2) is heated, its surface being coated dtune layer (21) non-stick.