EP3849748A1

EP3849748A1 - Method for tightening a screw for fastening a construction panel to a support

Info

Publication number: EP3849748A1
Application number: EP19762162.6A
Authority: EP
Inventors: Pierre Lombard; Jean-Yvon FAOU
Original assignee: Saint Gobain Placo SAS
Current assignee: Saint Gobain Placo SAS
Priority date: 2018-09-13
Filing date: 2019-09-04
Publication date: 2021-07-21
Also published as: FR3085876B1; FR3085876A1; WO2020053052A1; CA3112492A1; US20220032411A1; US11865654B2

Abstract

The invention relates to a method for tightening a screw for fastening a construction panel to a support of the construction panel, in which the fastening screw is screwed through the construction panel and then through at least part of the support, characterized in that it comprises: - a monitoring of a change over time of a tightening torque (605) of the fastening screw, with determination of a first maximum torque value (610) and then of a second minimum torque value (620), and - after determination of the second minimum torque value (620), a stoppage of the tightening of the fastening screw for a torque value, termed stoppage value (640), corresponding to a third maximum torque value (630) or being determined after an occurrence of a third maximum torque value (630).

Description

METHOD OF TIGHTENING A SCREW FOR FIXING A CONSTRUCTION PANEL ON A SUPPORT

The field of the present invention is that of construction panels used in the building sector. The present invention finds a particularly interesting, but not exclusive, application to building panels designated under the name of "plasterboard", formed of a layer of plaster contained between two facing sheets, generally made of cardboard.

Construction panels are widely used in the building industry, for example for making partitions, walls, floors or ceilings, for covering such surfaces, thermally and / or acoustically insulating them, protecting these surfaces from humidity, or even double these surfaces. Construction panels are plates made of a material chosen according to its use. As an indication, mention may be made of construction panels comprising plaster, cement, wood or wood particles, synthetic materials, mixed fibers, mineral particles, or a mixture of these materials, these construction panels being able to furthermore be covered with a surface coating of a material distinct from the material chosen.

The construction panels are fixed on a frame which serves as their support. This fixing, carried out by means of fixing screws inserted into the frame through the building panel, ensures that each building panel is integral with the frame. Typically, the fixing screws pass through the construction panel and are screwed, then tightened, in the framework, so that the head of the fixing screws is inserted into the thickness of the construction panel, and is flush with the surface. of the last.

The screwing and tightening operations to be carried out may be accompanied by defects which adversely affect the mechanical quality of the fixing and / or the visual appearance of the subsequent finish, for example by application of one or more plasters and / or paintings, on the construction panel considered. A first screwing fault, also referred to as infinite screwing, relates to the case where a fixing screw turns endlessly in the frame. In such a case, the fixing screw considered cannot be tightened in the frame. There is therefore no mechanical strength of the construction panel on the latter.

Another screwing defect relates to the case where a fixing screw fails to penetrate or perforate the material constituting the framework of the construction panel. As in the case of infinite screwing, there is then no mechanical strength of the construction panel on its framework. As the screwing effort continues, such a situation can lead to deformation of the frame, damaging the installation of other fixing screws.

Another screwing fault relates to the case where the head of one or more fixing screws is prominent on the surface of the building panel. The subsequent aesthetic finishing operations of this surface then require more time, and require, for example, a resumption of screwing or the carrying out of additional operations to obtain a smooth and flat surface capable of receiving a finishing paint. .

Another screwing fault designates a case in which the tightening of a fixing screw is accompanied by a deformation of the material constituting the construction panel. Such a defect most often results in one or more deformations in thickness of the construction panel, deformations called "plaster hills" when they are encountered for construction panels such as plasterboards, previously mentioned. Like other visual defects, such a screwing defect has a significant impact on the time and cost of finishing the surface of this panel.

The object of the invention is to propose a solution making it possible to eliminate these mechanical and / or visual defects in screwing while guaranteeing a reliable and reproducible fixing of the construction panels on the framework.

For this purpose, the invention relates to a method of tightening a fixing screw of a construction panel on a support of the construction panel, in which the fixing screw is screwed through the construction panel and then to through at least part of the support, characterized in that it comprises: a monitoring of a temporal evolution of a tightening torque of the fixing screw, with determination of a first maximum torque value then of a second minimum torque value, and

- after determining the second minimum torque value, a stop in the tightening of the fixing screw for a torque value, called the stop value, greater than the first maximum torque value, the stop value corresponding to a third maximum torque value or being determined after the appearance of a third maximum torque value.

The term tightening generically designates here, as well as in what follows, the successive operations of screwing and blocking a fixing screw which lead to the fixing of a construction panel on a support of the latter.

According to one aspect of the invention, the fixing screw is screwed through the construction panel and then through at least part of the support by applying a clamping force continuously.

The first torque value is maximum in the sense that it is the first highest value observed during the temporal monitoring of the tightening torque. The second torque value is minimum in the sense that it is the lowest torque value observed, except for a process start and end value. The stop value is greater than the first maximum torque value and occurs after the second torque value.

If we draw a curve representing the values determined during the temporal monitoring of the tightening torque, the first maximum torque value and the second minimum torque value correspond to points on the curve where the derivative is canceled.

The construction panels to which the method according to the invention applies are panels used for example to cover, totally or partially, a wall of a building, or to produce a partition distinct from a wall, in particular a separating partition. The term building is here to be understood in the broad sense and can indifferently denote, in what follows, a building as a whole, a room or a set of rooms of a building. The construction panels targeted by the invention can be of various types and sizes: by way of nonlimiting examples, they can be plasterboard, wood panels or panels made of a composite material, for example base of wood fragments. Whatever their nature, they are in the general form of a rectangular parallelepiped of small thickness. In other words, these building panels have two main faces which are substantially planar, rectangular and parallel to each other, with the manufacturing tolerances apart, separated from one another by a thickness whose dimension is small with regard to the length and width of the main faces mentioned above.

Whatever their nature, the construction panels to which the invention applies are intended to be fixed on a support itself either autonomous, in particular in the case of a separating partition, or integral with the wall considered, being arranged for example parallel to this wall, in direct contact or at a distance therefrom. Such a wall can be, without limitation, a floor, a wall or a ceiling of a room in this building. With reference to a trihedron L, V, T defined by the conventional spatial orientations, respectively, horizontal, vertical and transverse, the above-mentioned wall can therefore be placed horizontally, in the case where the wall considered is a floor or a ceiling, vertically, in the case where the wall considered is a wall, or according to any combination of these orientations. Furthermore, the wall considered can be either an interior wall or an exterior wall of the building.

By support is meant any rigid element or set of rigid elements forming all or part of a frame adapted to receive one or more construction panels. The framework can be autonomous, in the sense that building panels can for example be fixed on either side of such a framework to form a separating partition, or arranged parallel to an existing wall. In the latter case, the support can be fixed against the existing wall by means of screws or by gluing. The support can also be attached at a distance from the wall and held in position, for example, by means of bracing devices fixed to the wall. Without limitation, the support can be made of metal, wood, or a composite material, for example based on wood fragments. By convention, the following will be designated as the exposed face of the construction panel the face thereof which remains visible once the construction panel is fixed to the support previously defined, and by the hidden face of a construction panel. the face thereof opposite the aforementioned exposed face. Exposed face and hidden face of a construction panel constitute the main faces, previously mentioned, of this construction panel.

A screw for fixing a construction panel to a support as defined above comprises a threaded part and a conical screw head. The threaded part is substantially cylindrical and it ends, at one of its ends in its main direction of extension, by a conical portion forming a point. At its opposite end in the aforementioned main direction of extension, the threaded part of the fixing screw is attached to the screw head mentioned above. The latter advantageously has a flared shape of coaxial revolution with the axis of revolution of the threaded part of the fixing screw.

By convention, the surface of the screw head by which the latter is attached to the threaded part of the fixing screw will be designated in the following as the lower surface of the screw head, the opposite surface of the screw head being, by convention, designated as the upper surface of the screw head. By extension, the following will be designated as the lower end of the fixing screw the end of the threaded part thereof forming the conical point previously mentioned, and by the upper end of the fixing screw the aforementioned upper surface of the screw head. Advantageously, the upper surface of the screw head is substantially planar and it has an imprint configured to receive a tightening tool. Advantageously, the screw head has a conical shape, the diameter of which increases from the threaded part of the fixing screw to the above-mentioned upper surface.

Advantageously, the stop value is representative of a position where an upper surface of the head of the fixing screw is coplanar with the main face delimiting the construction panel. Alternatively, this stop value can also be representative of a position of the upper surface of the head of the fixing screw included in the construction panel. According to this aspect, the upper surface of the head of the screw is arranged in the thickness of the construction panel, between its main faces. The stop value corresponds to a third maximum torque value or is determined, in particular measured, after an appearance of a third maximum torque value.

This third maximum torque value corresponds to an inversion of the tightening torque curve occurring after determination of the second minimum torque value. Its value is moreover greater than the first maximum torque value.

This third maximum torque value can be measured. When monitoring the evolution of the tightening torque, it is determined in the same way as the first maximum torque value and the second minimum torque value. Alternatively, this third maximum torque value can be determined beforehand by tests or by calculation.

The tightening torque here illustrates the effort provided to tighten a fixing screw of a construction panel as previously mentioned on a support as previously defined. The tightening torque can, for example, be measured by a tightening torque sensor associated with a tightening tool used to tighten the fixing screws.

In more detail, a fixing screw is first positioned on the exposed face of the building panel, substantially perpendicular thereto, the point formed at the lower end of the fixing screw being placed in contact with the exposed side. The fixing screw is then inserted through the thickness of the building panel, until the conical point punctures the support in which it must be tightened.

In the case where the building panel is a plasterboard consisting of a layer of plaster interposed between two cardboard facing sheets, the fixing screw successively punctures the facing layer forming delimiting a first main face of the building panel, then the plaster thickness, then the facing layer forming a second main face of the construction panel, before being in contact with the support on which the construction panel must be fixed.

The fixing screw must thus overcome the resistance of the material forming the facing layers, then that of the material, for example plaster, before conquering the resistance of the material, for example metal, forming the support on which the building panel is fixed. The perforation and widening of the support until substantially reaching the diameter of the threaded part of the fixing screw corresponds to the first maximum value of tightening torque.

During this tightening phase, the tightening torque applied to the fixing screw gradually increases, until reaching this first maximum torque value, also designated in the following as the perforation value.

During a second tightening phase, the fixing screw is screwed into the support. During this phase, the fixing screw must overcome the resistance to its progression in the thickness of the support of the construction panel. The tightening torque applied to the fixing screw therefore decreases up to a second minimum torque value, or screwing value, less than the first previously defined maximum torque value.

When tightening continues, the head of the fixing screw rubs against the main face of the building panel. More specifically, the lower surface of the screw head is in abutment against the exposed face of the building panel. As the tightening continues, the conical shape of the screw head results in a further increase in the tightening force applied to the fixing screw, resulting from the resistance to penetration of the conical part of the screw head into the thickness of the construction panel. There is therefore a rapid increase in the tightening torque applied to the fixing screw, until it reaches a value, called the stop value, ensuring that the construction panel is correctly secured to its support, without destruction. of the construction panel or without deformation likely to generate an aesthetic defect. This stop value is determined to be greater than the first maximum torque value.

According to the method of the invention, the tightening operation is stopped as soon as the tightening torque corresponds to this stop value, also called stop value.

According to an advantageous arrangement of the invention and as indicated above, the stop value can correspond to or be successive to a third maximum torque value. In other words, the tightening operation is stopped when the tightening torque is close to the third maximum tightening value, corresponds to a third maximum value of the tightening torque, or has temporally exceeded this. When the stop value corresponds to or is determined after the third maximum torque value, the invention guarantees that the upper surface of the head of the fixing screw is coplanar with the main face of the building panel, or at most slightly depressed within the latter. This arrangement prevents any mechanical interference with the head of the fixing screw, as may be the case in the prior art when the latter emerges from the construction panel, for example when the tightening has not been carried out using the means of the invention. Covering the building panel with plaster is thus facilitated since the screw does not form an emerging part.

Furthermore, if the upper surface of the head of the fixing screw comes to be pressed into the construction panel following a stop value of the screwing process determined after the third maximum torque value, the invention guarantees that this depression is light enough not to destroy the material of the construction panel, such as plaster for example. The coating of the construction panel by plastering is thus done without discomfort, which can be the case when the depression of the fixing screw is too deep within the construction panel.

The stop controlled by the method according to the invention ensures a perfect position of the screw head and thus facilitates the posterior coating step.

The third maximum torque value is greater than the first maximum torque value and the second minimum torque value. The first maximum torque value is greater than the second minimum torque value.

According to one aspect of the invention, the stop value is calculated and / or determined beforehand by test, in particular by several tests making it possible to determine an average of the tests which forms the stop value.

According to an exemplary embodiment, the stop value is part of or constitutes a decreasing phase of the tightening torque, such a decreasing phase being subsequent to the third maximum torque value. According to another exemplary embodiment, the stop value is part of an increasing phase of the tightening torque, such an increasing phase being subsequent to the third maximum torque value, the stop value being nevertheless less than or equal to the third maximum torque value.

On a practical level, the invention advantageously provides for a phase of comparison of the tightening torque applied to the fixing screw with the previously defined stop value, the tightening stop being carried out as soon as the tightening torque reaches the value above-mentioned stop.

The invention advantageously provides for a measurement, at predefined time intervals, of the tightening torque applied to the fixing screw, as well as a comparison between them of the measured values of this tightening torque. More specifically, the invention provides for the comparison, in pairs, of the values of the tightening torque measured consecutively. In other words, the invention provides for a measurement to be made, at predefined time intervals, of the tightening torque applied to the fixing screw, and for the last measured value to be compared with the immediately preceding measured value.

Alternatively, the tightening torque measurements making it possible to carry out the comparisons mentioned above can be carried out at an interval of angular values of rotation of the tightening tool, in particular every 1/8 of a turn.

The invention provides that the phases of comparison of values mentioned above are replaced by a calculation of the derivative of the curve of the torque values, the first maximum torque value and / or the second minimum torque value being identified by the causes the derivative to be zero at this point on the curve.

The method which is the subject of the invention can thus comprise a step of subtracting two successive tightening torque values but separated by a determined time, and where the crossing of the first maximum torque value is determined by a result of this subtraction which is greater than or equal to zero. Such a subtraction step may include a step of smoothing the measured torque values.

According to one aspect of the invention, the subtraction step is implemented to determine a crossing of the second minimum torque value, this crossing being determined by a result of subtracting two consecutive tightening torque values separated by a determined time, which is less than or equal to zero. During this reversal of the tightening curve, a tightening torque value after the second minimum tightening value is greater than or equal to a torque value before this second minimum tightening value, which results in a lower result or equal to zero.

The time interval mentioned here for performing the torque measurements and making the comparisons or subtractions is of the order of a millisecond, guaranteeing a reliable sampling of the measurements.

These subtractions make it possible to determine the tightening torque inversions which occur at the level of the first maximum torque value and at the level of the second minimum torque value. By knowing these inversions, the process can identify which stage it is in during the tightening process.

By implementing the steps defined above, the invention makes it possible to avoid any deformation of the construction panel and of its support, while ensuring that the construction panel is correctly fixed thereon. The invention thus makes it possible to overcome the mechanical defects of screwing previously defined.

Indeed, if the fixing screw fails to perforate the support on which the construction panel is to be fixed, for example in the case where the conical tip is blunt, the tightening torque does not reach the perforation value previously defined, from which it is supposed to decrease until reaching the screwing value. It is therefore possible to define a maximum duration beyond which the screwing will be considered as defective, the tightening torque not having reached the first maximum torque value from which it is supposed to decrease.

If the fixing screw turns in a vacuum, the stop value, previously defined, is not reached. Again, it is possible, for example, to define a maximum duration beyond which the screwing will be considered defective, the tightening torque not having reached the previously defined stop value. The invention, as it has just been described, makes it possible to eliminate the main tightening faults which may occur when a building panel is fixed to a support of the latter.

The invention also extends to a tightening tool configured to implement a tightening method as just described.

Such a clamping tool advantageously comprises a male or female part configured to cooperate with the impression made in the upper surface of the fixing screw, in order to ensure the grip of the clamping tool on the latter. Advantageously, the male or female part of the clamping tool has a main elongation axis around which it is movable in rotation. When implementing the method according to the invention, the tightening tool and the fixing screw to which it is applied are arranged in such a way that the axis of rotation of the male or female part of the clamping, designated by extension in the following as the axis of rotation of the clamping tool, is substantially coincident with the axis of revolution of the threaded part of the fixing screw considered. Thus, when the tightening tool is rotated about its axis of rotation to carry out the method according to the invention, the male part which it comprises drives the fixing screw in rotation around its axis of revolution.

The invention also extends to a device for clamping a fixing screw intended to fix a construction panel to a support of the latter, the aforementioned clamping device comprising a clamping tool as described above, the device for tightening being equipped with a system for measuring the tightening torque applied to the aforementioned fixing screw and with a device for stopping the tightening tool as a function of the tightening torque measured, in particular for a torque value, called stop value, greater than a first maximum torque value and determined after a second minimum torque value.

The torque measurement system of the tightening tool may include at least one means for detecting the first maximum torque value and / or the second minimum torque value and / or a third maximum torque value.

According to different embodiments of the invention, the system for measuring the tightening torque is, for example, mechanical or electronic. It can, for example, be a torque or an electric current sensor consumed by the tightening tool.

According to an exemplary embodiment, the device for stopping the clamping tool is a member which cuts off the electrical supply to the clamping tool. The clamping tool stop device can also be a mechanical means of blocking or disengaging the rotation of the clamping tool.

Advantageously, the clamping device according to the invention can also have one or more of the following characteristics, taken separately or in combination:

- The clamping device according to the invention comprises a damping system configured to compensate for variations in the speed of movement of a thrust plate constituting the clamping device. The presence of the previously defined damping system makes it possible, by homogenizing the force exerted on the upper surface of the head of the fixing screw and by guaranteeing permanent contact between the impression made in the latter and the male or female form of the clamping tool, compensating for or eliminating these differences in the speed of descent of this thrust plate,

- The damping system comprises, on the one hand, at least one threaded rod having a main elongation axis around which it is rotated by a translation motor of the clamping tool, at least one threaded rod being configured to drive in translation the thrust plate in a direction substantially parallel to the axis of rotation of the threaded rod, and on the other hand, a spring disposed between the thrust plate and the previously mentioned tightening tool. It should be noted that, in the case where the damping system comprises several threaded rods, these are advantageously parallel to one another. The thrust plate linked to at least one threaded rod is driven in translation in a direction substantially parallel, apart from manufacturing tolerances, to the direction of the common axis of rotation of the threaded rod (s). Advantageously, this common axis of rotation is parallel to the axis of rotation common to the clamping tool, that is to say to the direction in which the fixing screw is inserted in the construction panel. It follows from the above that, in its translational movement, the thrust plate exerts a force, directed in the direction of the axis of rotation of the clamping tool, on the spring placed between the thrust plate and the clamping tool. The spring aforementioned then exerts, in turn, a force on the clamping tool. Advantageously, two threaded rods and two springs are symmetrically arranged with respect to the axis of rotation of the clamping tool.

The invention also extends to a portable tool with manual control which includes a clamping device as mentioned in this document. It can for example be a screwdriver, for example cordless, equipped with a system for measuring the tightening torque applied to the fixing screw, for example a tightening device of the torque wrench type.

The invention also covers a screwing robot which includes a clamping device as mentioned in this document. This screwing robot has at least one base configured to be fixed to a floor and is equipped with an arm at one end of which is placed the tightening tool, the movements of the tightening tool and the arm which carries it being governed by an electronic piloting unit. Such a screwing robot is a heavy industrial means used in the context of repetitive screwing operations.

The invention finally extends to an automated device configured to move in abutment on a construction panel, the automated device comprising a frame carrying a clamping device as just described, configured to produce at at least one operation for fixing the construction panel to a support for the construction panel, the automated device comprising at least one member for holding the automated device against the construction panel and at least one means for moving the automated device along the construction panel.

It should be understood here that the automated device according to the invention moves against the exposed face, previously defined, of the building panel, and that, in this displacement, the automated device according to the invention remains in permanent contact with this face, whatever whatever the spatial orientation of the construction panel. This permanent contact is provided by the holding member which is formed, for example, by a suction member, the latter comprising at least one sealing device and a plate constituting the chassis, which delimit a vacuum chamber. Once the automated device is pressed against the construction panel, the vacuum chamber is closed by the exposed face of this panel against which the automated device is placed, the suction member further comprising a means for placing under vacuum opening into the aforementioned vacuum chamber.

According to an exemplary embodiment of the invention, the means for setting in motion the automated device comprises a setting in motion motor, for example an electric motor supplied with current by a home network or by an electrical storage device on board the chassis. . The latter advantageously comprises one or more means of movement such as, by way of nonlimiting examples, wheels, tracks or legs.

Advantageously, the automated device comprises a control unit configured to control the operation of the holding member, the operation of the means for setting in motion, as well as the operation of the clamping device configured to implement the method according to the invention , including the control of a damping system as previously described.

Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below for information, in relation to the following drawings, in which:

FIG. 1 is a schematic perspective illustration of a context for applying the invention,

FIG. 2 is a schematic sectional view, along a plane containing its axis of revolution, of a fixing screw,

FIG. 3 is a curve illustrating the variations in the tightening torque applied to a fixing screw during the implementation of the method for fixing a construction panel to its support,

FIG. 4 is an enlargement of part of the curve according to FIG. 3 illustrating a method of determining the stop value,

- Figures 5, 6, and 7 illustrate various relative positions of a fixing screw, a construction panel and the support thereof during the various stages of the process according to the invention illustrated in FIG. 3,

FIG. 8 is a schematic view of a first embodiment of a tightening device according to the invention,

FIG. 9 is a schematic view of a second embodiment of a tightening device according to the invention,

FIG. 10 is a schematic sectional view illustrating a damping system according to the invention, and

- Figure 11 is a schematic perspective view of an automated device according to the invention.

It should first of all be noted that if the figures show the invention in detail for its implementation, these figures can of course be used to better define the invention if necessary. It should also be noted that the same elements are designated by the same references on all of the figures.

FIG. 1 illustrates a general context of application of the method which is the subject of the invention. This figure shows schematically, seen from the inside, part of a room 700 of a building. In Figure 1 are visible a ceiling 1, as well as two walls, respectively 20, 21, of the room 700. In Figure 1 is also represented a direct trihedron (L, T, V) representing the three directions of space , respectively a horizontal direction L, a vertical direction V, and a transverse direction T. In FIG. 1 is also schematically represented an opening 3 arranged in the wall 20: the opening 3 can, for example, be intended to receive a window . The room 700 advantageously comprises one or more other walls, as well as a floor, not shown in FIG. 1.

The ceiling 1 and the walls 20, 21 each form a wall of the room 700, intended to be covered by one or more construction panels 4. In the following, the invention will be described and illustrated in the context of a construction panel 4 intended to be attached against any of the aforementioned walls, it being understood that the elements and characteristics described for such a construction panel 4 apply to any construction panel 4 intended to be attached to a support independent of a wall, as is the case of a separating partition.

According to different examples, the construction panel 4 can comprise a layer of plaster sandwiched between two facing sheets, thus constituting a panel known by the name of plasterboard. The construction panel 4 can also be made of wood or of a composite material comprising fragments of wood assembled together, for example by a resin.

In all cases, whatever the material chosen, the construction panel 4 is advantageously a plate whose general shape is substantially that of a rectangular parallelepiped, of which a length 40, partially shown in FIG. 1, and a width 41 are large in front of the thickness 42, visible in Figures 5 to 7, measured perpendicular to the length 40 and the width 41 above. Typically, the length 40 and the width 41 of such a construction panel 4 vary from a few tens of centimeters to a few meters, and the thickness 42 of such a panel 4 is of the order of a few millimeters to a few centimeters.

The construction panel 4 has a first main face, or inner face 43, visible in FIG. 5, and a second main face 44, or exposed face, substantially rectangular and parallel to each other, each having the length 40 and the width 41 mentioned above. , separated from each other by the thickness 42 previously defined. The second main face 44 is the face of the construction panel 4 intended to remain visible from the interior of the part 700: it will also be designated in the following as the exposed face of the construction panel 4. The interior face 43 is the face of the construction panel 4 opposite the second main face 44 mentioned above: it will be designated in the following as the hidden face of the construction panel 4.

According to different embodiments, the support 5 can be metallic, it can be synthetic, it can be made of wood, or it can be formed from a composite material, for example based on wood fragments and a resin. Whatever the material, the support 5 is a rigid element either made integral with the wall, for example by screws, bolts, staples, hangers or glued to it, or independent of this wall to form a separating partition separate from the wall.

According to different embodiments, the support 5 can be in the form of one or more rectilinear rails, for example of square or rectangular section along a plane perpendicular to their main direction of elongation. Advantageously, these rails can be arranged in a network on the wall intended to receive the construction panel, so as to form together a mesh thus constituting a support frame 5 for the construction panel or panels 4.

According to the embodiment more particularly illustrated in Figure 1, the support 5 comprises a first set of rails 50 and a second set of uprights 51, otherwise called furs. The rails 50 of the first set and the uprights 51 of the second set are substantially perpendicular to each other. The rails 50 and the uprights 51 thus form a network of bars constituting the framework integral with the ceiling 1 or the wall 20, 21, the framework on which the construction panels 4 are intended to be fixed.

As shown in FIG. 1, the construction panel 4 is advantageously fixed on the rails 50 of the first set of rails, for example by a set of fixing means 6. It follows from the above that a fixing means 6, for example a screw inserted, in the vertical direction V, in the vicinity of an edge 45 of the construction panel 4, crosses the construction panel 4 and enters one of the rails 50. It should be noted that certain fixing means 6 can be inserted into one of the uprights 51 without harming the invention. Furthermore, the direction of the fixing means 6 is vertical, but it is understood that the invention applies to a tightening of a fixing means arranged horizontally.

The fixing means 6 are advantageously fixing screws, one of which is shown diagrammatically in FIG. 2.

Referring to Figure 2, a fixing screw 6 comprises a threaded portion 60 which mainly extends in the direction of a main axis of revolution 600, and a head 61 of the screw fixing 6. At one of its ends in the direction of the aforementioned axis of revolution 600, designated as the lower end of the fixing screw 6, the threaded part 60 comprises a conical tip 62, coaxial with the axis of revolution 600.

At its opposite end in the direction of the axis of revolution 600, the threaded part 60 is attached to the head 61 of the fixing screw 6. The latter has a conical shape, the axis of which coincides with the axis of revolution 600 previously defined, which thus forms an axis of rotation of the assembly of the fixing screw 6. Unlike the portion by which it is attached to the threaded part 60, the head 61 of the fixing screw 6 has a substantially planar surface 63, designated in the following as the upper surface 63 of the fixing screw 6. The conical shape of the head 61 of the fixing screw 6 has a surface 65 which joins the threaded part 60 to the upper surface 63 of the head 61 of the fixing screw 6.

The upper surface 63 has substantially the shape of a disc, the diameter of which is greater than the diameter of the threaded part 60. Advantageously, the upper surface 63 comprises an imprint configured to receive a tightening tool 8, illustrated in FIGS. 8 to 11. When tightening the fixing screw 6, the tightening tool 8 drives the fixing screw 6 in rotation about its axis of rotation 600 previously defined: thanks to the threading of the threaded part 60, the latter then progresses in translation with within the material in which it is inserted.

FIG. 3 illustrates the process which is the subject of the invention. It has a curve illustrating the variations in the tightening torque 605 applied to a fixing screw 6 during a tightening process according to the invention.

It should be understood that here tightening means all the phases leading to a stable mechanical connection of the construction panel 4 on its support 5, in which the relative degrees of freedom of the construction panel 4 and of the support 5 are zero at the outcome of tightening all of the fixing screws 6 used for fixing the construction panel 4 to the support 5.

In FIG. 3 are shown, on the abscissa, the time t, and on the ordinate, the tightening torque 605 applied to the fixing screw 6. It should be noted that this curve illustrates the trends of variation of the tightening torque 605 and that slight deviations from the casing shown in FIG. 3 can occur, for example under the effect of variations in uniformity of the materials which constitute the construction panel 4 and the support 5.

The curve of FIG. 3 illustrates a monitoring of a temporal evolution of a tightening torque of the fixing screw 6. This monitoring is carried out by a torque measurement system and the latter is able to determine the appearance of a first maximum torque value 610 and a second minimum torque value 620, after the first maximum torque value 610. According to the invention, the method monitors a torque value, called the stop value 640, which is greater in value than the first maximum torque value 610 and which is successively determined by the second minimum torque value 620.

In the example illustrated in Figure 3, the method provides that the clamping force is applied continuously, that is to say without interrupting the rotation from the rotation of the fixing screw 6 to on the occurrence of the stop value 640.

According to an advantageous embodiment described in more detail below, this stop value 640 corresponds or is successive to a third maximum torque value 630. Once this stop value is determined, the method orders a stop of the tightening the fixing screw.

In its general formulation, the invention nevertheless provides for a stop of the tightening for a stop value 640 occurring before the occurrence of a third maximum torque value 630, as long as this stop value 640 is later than the second minimum value torque 620 and greater in value than the first maximum torque value 610.

Figures 5, 6 and 7 illustrate various relative positions of the fixing screw 6, the construction panel 4 and the support 5 during the different stages of the method according to the invention.

In a first step 100 of tightening the screw 6 according to the invention, illustrated by a first portion 601 of the curve presented in FIG. 3, the tightening torque 605 applied to the fixing screw 6 increases to a first value maximum torque 610, or perforation value. As mentioned above and as illustrated by FIG. 5, the first tightening step 100 corresponds to the passage of the fixing screw 6 through the thickness 42 of the construction panel 4, then to the perforation of the support 5 by the fixing screw 6. More precisely, during this first step 100, the fixing screw 6 is first of all positioned on the construction panel 4, in line with a rail 50 or an upright 51 of the support 5. The tightening tool 8, visible in FIGS. 8 to 11, is put into operation in such a way that it drives the fixing screw 6 considered in rotation about its axis of revolution 600. Until the operation of the tightening tool 8, the tightening torque 605 applied to the fixing screw 6 considered is zero.

Under the effect of the rotation driven by the clamping tool 8, the tip 62 formed at the lower end of the fixing screw 6 firstly perforates the second main face 44, or exposed face, of the construction panel 4. Under the effect of its rotation about its axis of revolution 600 and thanks to its threaded part 60, the fixing screw 6 then progresses through the thickness 42 of the construction panel 4, until the tip 62 perforates the interior surface 43, or hidden side, of the construction panel 4. The tip 62 of the fixing screw 6 is then in contact with one of the rails 50 or uprights 51, previously defined, of the support 5, which it in turn perforates.

During this first tightening step 100 illustrated in FIGS. 3 and 5, it follows from the nature and mechanical properties of the different materials constituting the construction panel 4 and the support 5 that, on the one hand, the tightening torque 605 increases continuously when the fixing screw 6 pierces, then passes right through, the construction panel 4, and that, on the other hand, the first value 610 of the tightening torque 605 is reached during the perforation and during the enlargement of the hole made in the material constituting the support 5, which has the highest penetration resistance at this stage of the process.

The method determines the existence of this first maximum torque value 610 by implementing a step of subtracting torque values at determined time intervals, in particular of the order of a millisecond. The result of this subtraction determines the reaching of the first maximum torque value 610 and the passage of the first step 100 in a second step 200. According to this determination mode, a step of subtracting tl-t2 from two successive tightening torque values tl and t2 is carried out. The torque value illustrated by the reference t2 is temporally consecutive to the torque value illustrated by the reference tl and separated from tl by a determined non-zero time. This time corresponds for example to the sampling time of the torque values, in particular of the order of a millisecond. The crossing of the first maximum torque value 610 is determined by a result of this subtraction tl-t2 which is greater than or equal to zero.

According to another example, the existence of the first maximum torque value 610 can be determined from angular measurement of the rotation of the tightening tool, in particular when the motor which drives the tightening tool is an electric motor not -in step.

According to yet another example covered by the invention, the first maximum torque value 610 is a point, in a set of points forming an evolution curve of the tightening torque, where the derivative is canceled.

In this second tightening step 200, illustrated by a second portion 602 of the curve presented by FIG. 3 and by FIG. 6, the tightening torque 605 applied to the fixing screw 6 decreases, up to a second minimum value of torque 620, or tightening value. This second minimum torque value 620 is less than the first maximum torque value 610.

During this second step 200, the fixing screw 6 is gradually screwed into the support 5, that is to say that, under the effect of the rotation imparted by the tightening tool 8, it progresses within the support 5 along the direction of its axis of revolution 600. The resistance to progression of the fixing screw 6 within the support 5 being lower than the resistance to perforation of the support 5 by the tip 62 of the fixing screw 6, the tightening torque 605 applied to the fixing screw 6 decreases from the first maximum torque value 610 previously defined, until the lower surface 65 of the head 61 of the fixing screw 6 is in contact with the second main face 44 of the construction panel 4.

The method determines the existence of this second minimum torque value 620 in implementing the step of subtracting torque values tl and t2 as detailed above with respect to the first maximum torque value 610. The result of this subtraction determines the achievement of the second minimum torque value 620 and the passage from the second step 200 to a third step 300, as soon as the result of the subtraction tl-t2 is less than or equal to zero.

According to another example, the existence of the second minimum torque value 620 can be determined from angular measurement of the rotation of the tightening tool, in particular when the motor which drives the tightening tool is an electric motor not -in step.

According to yet another example covered by the invention, the second minimum value of torque 620 is a point, in a set of points forming an evolution curve of the tightening torque, where the derivative is canceled.

In the third tightening step 300 of the method according to the invention, illustrated by a third portion 603 of the curve presented in FIG. 3 and in FIG. 7, the tightening torque 605 applied to the fixing screw 6 considered increases again to exceed the first maximum torque value 610.

According to a first implementation of the invention, a stop value 640 determines a stop in the tightening of the fixing screw. This stop value 640 can take any value of tightening torque greater than the first maximum torque value 610, as long as this stop value appears after the second minimum torque value 620.

In the example illustrated in FIG. 3, the tightening torque 605 applied to the fixing screw increases up to a third maximum value of torque 630.

According to an advantageous embodiment of the invention, the method is able to determine the appearance of this third maximum torque value 630, either by comparison of successive torque values measured instantaneously, or by operating a derivative of these values of couple. This third maximum torque value 630 can also be calculated or even result from tests and thus form a threshold with which the measurement of the torque operated during monitoring makes a comparison. During this third step 300, under the effect of the rotation of the fixing screw 6, the head 61 of the fixing screw 6 penetrates into the thickness 42 of the construction panel 4, progressively blocking the latter against the support 5. It results from the conical shape of the head 61 of the fixing screw 6 and the relative dimensions of the latter relative to the threaded part

60 of the fixing screw 6, that the tightening torque 605 applied to the fixing screw 6 increases rapidly during this third step 300, from the second minimum value of torque 620, which therefore constitutes a minimum in operation, such as shown on the curve shown in Figure 3.

To avoid any mechanical deformation of the construction panel 4 and / or of the support 5 by excessive screwing, damaging the mechanical strength of the assembly formed by the construction panel 4 and the support 5, as well as the aesthetics of the subsequent finishing of the second main face 44 of the construction panel 4, the tightening of the fixing screw 6 must advantageously be stopped when the upper surface 63, previously defined, of the head

61 of the fixing screw 6, is flush with the second main face 44 of the construction panel. It has been determined that this third maximum torque value 630, or values which are close to it, before or after this third maximum torque value 630, are typically representative of a position of the fixing screw 6 where its upper surface 63 is coplanar with one of the main faces 43, 44, that is to say the exposed face 44 which delimits the construction panel 4. This third maximum torque value 630 can also correspond to an inclusion in the panel construction 4 of the upper surface 63 of the fixing screw 6, such an inclusion being a positioning of this upper surface 63 between the two main faces 43, 43 which delimit the construction panel 4.

To do this, the method according to the invention comprises a fourth stop step 400 illustrated by a fourth portion 604 of the curve presented in FIG. 3. During the fourth step 400, the tightening of the fixing screw 6 considered is stopped as soon as the third maximum torque value 630 of the tightening torque 605 applied to the fixing screw 6 is approached, reached or temporarily exceeded by the stop value 640. The tightening torque 605 then drops to return to a value null, corresponding to the stop of the rotation of the fixing screw 6. It therefore follows from the above that the third maximum torque value 630 is a maximum value of the tightening torque 605 during the tightening process according to the invention.

FIG. 3 also shows that the stop value 640 can either correspond to the third maximum torque value 630, or be prior to it along a torque curve which increases towards the third maximum torque value 630, or be it successively along a decreasing torque curve. The stop value 640 can thus be part of an increasing phase of the tightening torque 605, such an increasing phase of the tightening torque being prior to the third maximum torque value 630. The stop value 640 can also be part a decreasing phase of the tightening torque 605, such a decreasing phase of the tightening torque being subsequent to the third maximum torque value 630.

When the stop value 640 corresponds to or is successive to the third maximum torque value 630 during the decreasing phase of the torque curve, the upper surface 63 of the fixing screw 6 is then coplanar with the second main face 44 of the construction panel 4. The presence of the fixing screw 6 therefore does not create mechanical interference if a covering of the construction panel 4, for example by coating, comes to be carried out.

When the stop value 640 is successive to the third maximum torque value 630, the invention also provides that the upper surface 63 of the fixing screw 6 is slightly pressed into the thickness 42 of the construction panel 4. Such a sinking is operated so as not to tear the facing layer of the building panel, the latter may for example be a cardboard sheet. Furthermore, the depth of the head 61 of the fixing screw 6 in the thickness of the panel is not restrictive in the event of covering by coating of the construction panel 4, in the sense that it does not generate form cavities. air bubble.

Alternatively and as illustrated in FIG. 4, the stop value 640 can either correspond to the third maximum torque value 630, or be successive along a curve of torque which increases, as long as the value stop 640 remains less than or equal to the third maximum torque value 630. As shown in FIG. 3, the third maximum value 630 of the tightening torque is greater than the first maximum value of torque 610, that is to say that the maximum of the tightening torque 605 reached when the head 61 of the screw 6 is locked in the thickness 42 of the construction panel 4 is greater than the maximum reached during the perforation, by the point 62 of the fixing screw 6, of the support 5.

According to an advantageous embodiment, the first maximum torque value 610, the second minimum torque value 620 and the third maximum torque value 630 previously mentioned result directly from torque measurements carried out in situ, that is to say during monitoring the time course of the tightening torque of the fixing screw 6.

According to other exemplary embodiments, the third maximum torque value 630 can be defined by a calculation, as a function of the size of the fixing screws 6 and the mechanical properties of the materials constituting the fixing screws 6, the construction panel 4 and the support 5. The third maximum torque value 630 can also be defined empirically, for example when tightening one or more fixing screws 6 "controls" before tightening all the screws necessary for fixing the assembly of the construction panel 4 considered on the support 5. In these two cases, the third maximum torque value 630 forms a threshold that the torque value measured instantaneously during the third step 300 of the process must reach or exceed in order to cause the stop screwing.

In all cases, it follows from the above that the method according to the invention advantageously comprises a step of comparing values of the tightening torque 605, measured at different predefined times t, this comparison step verifying at least that the value d stop 640 is after the second minimum torque value 620 and that its value is greater than the first maximum torque value 610, the carrying out of the fourth step 400 of the method according to the invention being governed by the result of this comparison.

It follows from the above that the method can alternatively be understood as that which comprises a step of tightening the fixing screw 6 during which a tightening torque of this screw is followed, a first step 100 of tightening the screw fixing 6 until that the tightening torque 605 applied to the fixing screw 6 reaches a first maximum torque value 610, a second step 200 of tightening the fixing screw 6 until the tightening torque 605 applied to the fixing screw 6 reaches a second minimum torque value 620, the first maximum torque value 610 being greater than the second minimum torque value 620, a third step 300 of tightening the fixing screw 6 until the tightening torque 605 applied to the fixing screw 6 reaches a third maximum torque value 630, and a fourth step 400 of stopping the tightening of the fixing screw 6 when a stop value 640 of torque applied to the fixing screw 6 is close , reaches or exceeds the third maximum torque value 630.

It also follows from the above that the method according to the invention provides for the comparison, for example by subtraction, at previously defined time intervals Dt, of the values, respectively referenced 650, 651, of the tightening torque 605 applied to the screw. fixing 6 at times tl and t2 separated from each other by the time interval Dt. In other words, the invention provides for a measurement, at time intervals Dt, of the tightening torque 605 applied to the fixing screw 6 considered, as well as a comparison of the value 651 of the tightening torque, measured at a given instant t2, with the value 650 of the tightening torque, measured at the previous instant tl. The passage of the values thus measured of the tightening torque 605 by the first maximum torque value 610 thus provides information on the start of the second step 200 of the tightening process according to the invention, then the passage through the second minimum torque value 620 provides information on the start of the third step 300 of the method according to the invention.

Alternatively, a derivative of the measured torque values can also make it possible to determine the increasing or decreasing appearance of the torque curve 605, and thus to determine the crossing of the first maximum torque value 610, of the second minimum value of torque 620 and, optionally, of the third maximum torque value 630. The curve of FIG. 3 representing the values determined during the temporal monitoring of the tightening torque, the first maximum torque value 610 and the second minimum torque value 620, possibly the third maximum torque value 630, correspond to points on the curve where the derivative is canceled. Figure 8 and Figure 9 schematically illustrate two embodiments of a clamping device 800 configured to implement the method according to the invention as just described.

Figure 8 is a hand-operated hand tool 500 which includes a clamp 800 as described above. Such a portable tool with manual control 500 comprises a screwing head 80 configured to receive a tightening tool 8 itself configured to fit into the cavity formed in the upper surface 63 of the head 61 of the fixing screw 6 , not shown in FIG. 8. According to an advantageous example of embodiment, the screwing head 80 is configured to receive different clamping tools 8 whose shape is complementary to different forms of imprints arranged in the head 61 of the fixing screw 6, the various clamping tools 8 being interchangeable in the screwing head 80 as a function of the shape of the abovementioned impression.

The hand-held portable tool 500 according to the invention is advantageously formed of a body 810 provided with a grip handle 820. The clamping device 800 advantageously comprises a motor 830, for example an electric motor placed in the body 810 of the clamping device 800. According to different embodiments, the electric motor 830 can be supplied with current by a domestic network, or it can be supplied with current by a storage device 840, not shown in FIG. 8, for example fitted on a part of the body 810 of the clamping device 800.

The electric motor 830 rotates the tightening tool 8 carried by the screwing head 80, around an axis of rotation 850 of the aforementioned tightening tool 8. For implementing the method according to the invention, the clamping device 800 is positioned in such a way that the aforementioned axis of rotation 850 is substantially coincident with the axis of a fixing screw 6 of a building panel 4 on a support 5. The tightening tool 8 is then engaged in the impression made in the head 61 of the fixing screw 6, then driven in rotation by the electric motor 830, in turn driving in rotation the fixing 6.

The hand-held hand-held tool 500 according to the invention also comprises a system for measuring the tightening torque 860 applied to the fixing screw 6 when the implementation of the tightening process as described above, that is to say a system for measuring the tightening torque 605 developed by the tightening tool 8. Such a system for measuring the tightening torque is for example mechanical or electrical . It can be a torque measurement device. It can also be a device for measuring the current consumed by the electric motor 830.

The hand-held portable tool 500 according to the invention also comprises a device 870 for stopping the tightening tool 8 as a function of the measured tightening torque, in particular when the stop value illustrated in FIGS. 3 appears. or 4. For example, this stop device 870 can be mechanical and operate a mechanical blocking of the clamping device 800, or even a disengagement between the electric motor 830 and the clamping tool 8 preventing any rotation of the tool. tightening 8.

This stop device 870 can also be electric. According to this example, it is an electrical switch which interrupts the power supply to the electric motor 830 upon receipt of the tightening stop instruction from the torque measurement system 860.

FIG. 9 illustrates a second exemplary embodiment which implements the invention. It is a screwing robot 501 which comprises a tightening device 800 configured to implement a tightening method as previously described.

With reference to this figure, the screwing robot 501 comprises at least one base 801 intended to be made integral with the ground, as well as an arm 802 equipped with a screwing head 80, itself carrying a tightening tool 8 as previously defined. Similarly to the example illustrated in FIG. 8, the screwing head 80 is advantageously configured to receive tightening tools 8 of different shapes in order to implement the method according to the invention for different shapes of impressions made in the head 61 of the fixing screw 6, not shown in FIG. 9.

The movements of the screwing robot 501 are here governed by an electronic control unit 805 configured in particular to control the movements of the aforementioned arm 802, as well as the movements of the tightening tool 8, in particular the rotation of the latter by a electric motor 830 that the screwing robot 501 includes.

As in the embodiment of FIG. 8, the screwing robot 501 comprises a device 870 for stopping the tightening tool 8 as a function of the measured tightening torque. For example, this stop device 870 can be mechanical and operate a mechanical blocking of the clamping device 800, or even a disengagement between the electric motor 830 and the clamping tool 8 preventing any rotation of the clamping tool 8.

To avoid the occurrence of certain tightening faults, the tightening device 800 advantageously comprises a damping system 85 and a thrust plate 852, more particularly illustrated in FIG. 10.

With reference to this FIG. 10, the damping system 85 notably comprises a translation motor 851 of the tightening tool 8, as well as two threaded rods 853 symmetrically disposed with respect to the axis of rotation 850 of the tool. tightening 8, and at least one spring 855 interposed between the thrust plate 852 and the screwing head 80. The translation motor 851 of the tightening tool 8 is, for example, an electric motor supplied with current by a domestic network or by an electrical storage device on board the tightening device 800 according to the invention.

The threaded rods 853 are substantially parallel to each other and to the axis of rotation 850 of the clamping tool 8, and they have an axis of revolution 854 in the direction of which they extend. The threaded rods 853 are linked to the translation motor 851 of the clamping tool 8 by a gear system 857 schematically illustrated in FIG. 10. The threaded rods 853 are thus driven in rotation about their axes of rotation 854 by the travel motor 851, via gear system 857.

The push plate 852 is a substantially flat part, linked to the aforementioned threaded rods 853. According to the embodiment more precisely illustrated in FIG. 10, the plate of thrust 852 is pierced by two orifices symmetrically disposed with respect to the aforesaid axis of rotation 850 and through which it is linked to the threaded rods 853. It therefore follows from the above that when the threaded rods 853 are rotated around their axes of rotation 854 by the translation motor 851, the thrust plate 852 moves in translation in the common direction of the axis of rotation 850 of the tightening tool 8 and the axes of rotation 854 of the threaded rods 853. More specifically, the damping system 85 is configured so that the thrust plate 852 moves in translation in the direction illustrated by the double arrow F in FIG. 10, that is to say in from or towards the head of tightening 80 of the tightening tool 8.

The screwing head 80 of the tightening tool 8, coaxial with the tightening tool 8, advantageously comprises a rotation motor 858 of the tightening tool 8, schematically represented in FIG. 10, and it is freely traversed by the threaded rods 853 previously described. The rotation motor 858 of the tightening tool 8 is, for example, an electric motor supplied with current by a domestic network or by an electrical storage device on board the tightening device 800 according to the invention.

At least one spring 855 is interposed between the screwing head 80 and the thrust plate 852. According to the embodiment more precisely illustrated by FIG. 10, a spring 855 is placed around each threaded rod 853, and it is interposed between an upper face 805 of the screwing head 80 and a lower face 8520 of the thrust plate 852.

When tightening a fixing screw 6 in the construction panel 4, the screwing head 80, under the effect of the progression of the fixing screw 6 in the construction panel 4, is driven in translation, according to the direction of the axis of rotation 850 of the clamping tool 8, towards the exposed face 44 of the construction panel 4.

Concomitantly, the translation motor 851 of the clamping tool 8 drives the threaded rods 853 in rotation simultaneously with the rotation of the fixing screw 6 driven by the rotation motor 858 of the clamping tool 8. Driven in translation according to the direction illustrated by arrow F, the thrust plate 852 then exerts, by means of the springs 855, a uniform thrust force on the upper face 805 of the screwing head 80. The aforementioned damping system 85 is thus configured to absorb a difference between the translation speed of the stage thrust 852 set the progression speed of the fixing screw 6 within the construction panel 4 and the support 5.

If the progression of the fixing screw 6 within the construction panel 4 is temporarily stopped, for example in the event of a temporary blocking of the fixing screw 6 in the construction panel 4, for example during any of the steps of the process, the translation of the screwing head 80 towards the exposed face 44 of the construction panel 4 is temporarily stopped. The pushing force described above continuing, the springs 855 are progressively compressed between the upper face 805 of the screwing head 80 and the lower face 8520 of the pushing plate 852. The pushing force they exert on the screwing head 80 then increases, facilitating the unlocking of the fixing screw 6 while maintaining the rotation of the latter at the constant speed of rotation of the tightening tool 8.

Conversely, if the progression of the fixing screw within the construction panel 4 is momentarily accelerated, for example if the fixing screw 6 is in a region of lower density of the construction panel 4 and / or of the material constituting the support 5 of the construction panel 4, the screwing head 80 moves in the direction of the exposed face 44 of the construction panel 4 more quickly than the thrust plate 852. The springs 855 then decompress, while maintaining, on the head of screwing 80, a pushing force sufficient to guarantee permanent contact between the tightening tool 8 and the head 61 of the fixing screw 6.

The aforementioned spring or springs 855 therefore make it possible to compensate for any variations in the speed of progression of the fixing screw 6 in the construction panel 4 and / or in the support 5 of the latter. The damping system 85 thus makes it possible to avoid any loss of contact between the tightening tool 8 and the head 61 of the fixing screw 6.

FIG. 11 illustrates an automated device 9 according to the invention, configured to move autonomously against a construction panel and to implement on the method according to the invention previously described in order to fix the configuration panel considered on a support of the construction panel. With reference to FIG. 11, the automated device 9 according to the invention comprises a frame 90 which has a generally substantially rectangular shape extending in a main direction of elongation X, or longitudinal direction of the automated device 9. With reference to the main direction of elongation X above, a transverse direction Y of the automated device 9 is defined, perpendicular to the main direction of elongation X above, and a vertical direction Z perpendicular to the plane defined by the longitudinal direction X and by the transverse direction Y above, so that the directions (X, Y, Z) form a direct trihedron. With reference to this direct trihedron (X, Y, Z), the frame 90 extends substantially mainly in a plane defined by the longitudinal direction X and by the transverse direction Y.

As illustrated in FIG. 11, the chassis 90 of the automated device 9 comprises a central part 900 carrying in particular a clamping device 800 configured to implement the method according to the invention, and two platforms 91 arranged on one side and other of the central part 900. In other words, the automated device 9 comprises, in this order and along its axis X of extension, a first platform 91, the central part 900 and a second platform 91.

As shown in Figure 11, the platforms 91 are interconnected by at least one reinforcement 910, advantageously two parallel reinforcements 910 arranged on either side of the clamping device 800. More particularly, these reinforcements 910 extend in two directions parallel to the axis X of extension of the chassis 90, and they are advantageously configured, on the one hand, to improve the resistance of the automated device 9 and, on the other hand, to stiffen the chassis 90 as a whole.

A platform 91 comprises a plate 92, at least one means for setting in motion 93 of the automated device 9 and a holding member. According to the example illustrated in this figure, the holding member of the automated device 9 against the construction panel takes the form of a suction member 94. The plate 92 is provided with a passage through which the air is aspirated to generate depression. The plate 92 comprises an outer peripheral strip where a sealing device 95 is disposed. The space between the plate 92, the construction panel, not shown in FIG. 11, and the sealing device 95 forms a chamber depression, the latter having a suction mouth intended to be positioned against the construction panel.

The suction member 94 comprises the sealing device 95 which, with the aforementioned plate 92, delimits the vacuum chamber where the vacuum takes place to hold the automated device 9 against the building panel.

The suction member 94 also includes a means for depressurizing the vacuum chamber, which forms the element generating depression in the vacuum chamber. By way of example, this means of depression, not visible in FIG. 11, takes the form of a propeller rotated by an electric motor on the shaft of which the propeller is arranged.

According to the embodiment more particularly illustrated by FIG. 11, the automated device 9 comprises two suction members 94 arranged on either side of the clamping device 800, in the longitudinal direction X of the automated device 9 according to the invention.

The sealing device 95 is configured to participate simultaneously in the vacuum generated by the suction member 94 and in the movements of the automated device 9 against the building panel. The sealing device 95 may be a seal made of a material specifically chosen for its mechanical properties or treated to give it the desired mechanical properties, for example by an appropriate surface treatment or by the addition of a film of a specific material chosen for its mechanical properties. The mechanical properties more specifically sought in the context of the sealing device 95 are, in particular, friction properties, the sealing having to be maintained when the automated device 9 according to the invention moves against a face of the building panel.

It follows from the above that the suction member 94 and its sealing device 95 allow that, in all the spatial positions of the automated device 9, the latter moves against an exposed face of the building panel, independently , and by remaining in permanent contact with the face on which it moves.

The automated device 9 simultaneously implements the device holding device automated 9 against the construction panel and the means of setting in motion 93 of the automated device 9. This means of setting in motion 93 comprises at least one electric motor associated with a wheel 96. As a non-exclusive example, the electric motor is for example supplied with current by a domestic electrical network or by an energy source on board the chassis 90, such as an electrical storage device.

As shown in FIG. 11, the chassis 90 carries four wheels 96 symmetrically distributed around the periphery of the chassis 90. The four wheels 96 allow the movements of the automated device 9 and its guidance during these movements. More specifically, the wheels 96 allow the automated device 9 to move against the exposed face of the building panel.

Advantageously, the automated device 9 comprises a control unit 950 configured to control the operation of the electric displacement motor, the operation of the holding member of the automated device 9 against the construction panel, as well as the operation of the clamping device 800 According to different exemplary embodiments, the control unit 950, schematically represented in FIG. 11, can be installed on the chassis 90 of the automated device 9.

With reference to FIG. 11, the automated device 9 comprises the clamping device 800 configured to implement the method according to the invention described above. According to the embodiment more particularly illustrated in FIG. 11, the clamping device 800 is placed in a substantially central position of the chassis 90, that is to say on the central part 900 of the automated device 9. In this particular example , the clamping device 800 mainly extends in a direction Z of extension perpendicular to the plane in which extends at least one of the plates 92 of the chassis 90.

The clamping device 800 illustrated in FIG. 11 comprises, in addition to a screwing head 80 fitted with a clamping tool 8 as defined above, a damping system 85 and a thrust plate 852 as described in relation to the FIG. 10. Reference will be made to the description of this FIG. 10 which applies mutatis mutandis to the damping system 85 which equips the automated device 9 of FIG. 11. According to this exemplary embodiment, a bracket 970 of the automated device 9 supports and stiffens the above-mentioned damping system 85. The bracket 970 comprises two balusters 971 symmetrically disposed on either side of the axis of rotation 850 of the clamping tool 8, not aligned with the threaded rods 853 previously described, for better balance of the assembly.

Advantageously, the control unit 950 is configured to control the operation of the tightening device 800, as well as the operation of the damping system 85.

The automated device 9 comprises a device 870 for stopping the tightening tool 8 as a function of the measured tightening torque. For example, this stop device 870 can be mechanical and operate a mechanical blocking of the clamping device 800, or even a disengagement between the electric motor 830 and the clamping tool 8 preventing any rotation of the clamping tool 8.

This stop device 870 can also be electric. According to this example, it is an electrical switch which interrupts the electrical supply to the electric motor 830 upon receipt of the instruction to stop tightening from the torque measurement system 860. In such a case, the stop device 870 can be housed in the control unit 950.

As just described, the invention achieves the goals it had set for itself, by allowing reliable, reproducible and flawless tightening of a screw for fixing a construction panel to its support.

The invention cannot however be limited to the means and configurations exclusively described and illustrated, and also applies to all means or configurations, equivalent and to any combination of such means or configurations. In particular, if the invention has been described here in its application to a substantially parallelepipedal construction panel, it goes without saying that it applies to any shape and / or dimension of construction panel.

Claims

1. Method for tightening a fixing screw (6) of a construction panel (4) on a support (5) of the construction panel (4), in which the fixing screw (6) is screwed through the construction panel (4) then through at least part of the support (5), characterized in that it comprises:

- monitoring of a temporal evolution of a tightening torque (605) of the fixing screw (6), with determination of a first maximum torque value (610) then of a second minimum torque value (620) ), and

- after determining the second minimum torque value (620), the tightening of the fixing screw (6) is stopped for a torque value, called the stop value (640), greater than the first maximum torque value ( 610), the stop value (640) corresponding to a third maximum torque value (630) or being determined after an appearance of a third maximum torque value (630).

2. Method according to the preceding claim, in which the stop value (640) is representative of a position where an upper surface (63) of a head (61) of the fixing screw (6) is coplanar with a main face (43, 44) delimiting the construction panel (4) or included in the construction panel (4).

3. Method according to any one of the preceding claims, in which the stop value (640) is calculated and / or determined beforehand by test.

4. Method according to any one of the preceding claims, in which the stop value (640) is part of a decreasing phase of the tightening torque, such a decreasing phase of the tightening torque being subsequent to the third maximum value of couple (630).

5. Method according to any one of claims 1 to 3, in which the stop value (640) is part of an increasing phase of the tightening torque, such an increasing phase of the tightening torque being subsequent to the third value. maximum torque (630), the stop value (640) being less than or equal to the third maximum torque value (630).

6. Method according to any one of the preceding claims, in which the determination of the first maximum torque value (610) and / or the second minimum torque value (620) is effected by subtracting two successive torque values.

7. Clamping device (800) of a fixing screw (6) intended to fix a construction panel (4) on a support (5) of the construction panel (4), characterized in that it comprises a tool tightening device (8) configured to implement a method of tightening the fixing screw (6) according to any one of the preceding claims, the tightening device (800) being equipped with a system for measuring the tightening torque (860) applied to the fixing screw (6) and a stop device (870) of the tightening tool (8) according to the measured tightening torque.

8. A clamping device (800) according to the preceding claim, in which the torque measurement system (860) of the clamping tool (8) comprises at least one means for detecting the first maximum torque value (610) and / or the second minimum torque value (620) and / or the third maximum torque value (630).

9. Clamping device (800) according to claims 7 or 8, characterized in that it comprises a damping system (85) configured to compensate for variations in the speed of movement of a thrust plate (852) constituting the clamping device (800).

10. Clamping device (800) according to the preceding claim, characterized in that the damping system (85) comprises at least one threaded rod (853) driven in rotation by a translation motor (851) of the tool. clamping (8), the threaded rod (853) being configured to drive in translation the thrust plate (852) in a direction substantially parallel to an axis of rotation (850) of the clamping tool (8), the system d damping (85) comprising at least one spring (855) disposed between the thrust plate (852) and the clamping tool (8).

11. Hand-held portable tool (500) comprising a clamping device (800) according to any one of claims 7 to 10.

12. Screwing robot (501) comprising a clamping device (800) according to any one of claims 7 to 10, the screwing robot (800) comprising a base configured to be secured to a floor and equipped with an arm (802) at one end of which the clamping tool (8) is placed, the movements of the clamping tool (8) and of the arm (802) which carries it being governed by an electronic control unit (805).

13. Automated device (9) configured to move in abutment on a construction panel (4), the automated device (9) comprising a frame (90) carrying a clamping device (800) according to any one of Claims 7 to 10, configured to carry out at least one operation of fixing the construction panel (4) to a support (5) thereof, the automated device (9) comprising at least one holding member (94) of the device automated (9) against the building panel (4) and at least one means for moving (93) the automated device (9) along the building panel (4).