EP2560797A1

EP2560797A1 - Guide for guiding the cutting of a piece of plasterboard, and kit and method for the implementation thereof

Info

Publication number: EP2560797A1
Application number: EP11720879A
Authority: EP
Inventors: Benoît MALLET
Original assignee: Individual
Current assignee: Jbme Innovations
Priority date: 2010-04-21
Filing date: 2011-04-18
Publication date: 2013-02-27
Also published as: FR2959156A1; FR2959156B1; US20130134201A1; WO2011132133A1

Abstract

The aim of the invention is to provide a solution for guiding the cutting of a piece of plasterboard, which can be rapidly implemented, and does not require any finishing step for refilling the surface of the piece of plasterboard. To this end, the invention relates to a guide element (200) for guiding the cutting of a piece of plasterboard, said guiding element having two longitudinal edges and two ends, for guiding a cutting blade, during operation, parallel to the guiding element, said guiding element also comprising, at least on one end, a rotatably mounted abutment (210) provided with means (211) for holding the abutment against the piece of plasterboard.

Description

GUIDE FOR CUTTING A PLASTER BOARD PANEL. KIT AND METHOD FOR IMPLEMENTATION

The invention relates to a cutting guide of a plasterboard board, a kit and a method of implementation.

A board of plasterboard is a panel made of a layer of plaster covered, on at least one side, by a sheet of cardboard or paper. Generally, both sides of the panel are covered by a sheet of cardboard or paper.

Gypsum boards are usually manufactured in the factory, and are used to make partitions, ceilings, double walls, etc. These panels therefore replace the use of powdered plaster diluted in water for coating walls, which is a tiring operation, long and requires significant expertise to obtain an optimal composition of the plaster and satisfactory flatness of the coated surface.

These panels have the advantage of being easy to handle and allow a quick job. In addition, the know-how necessary for their positioning is reduced compared to traditional plaster. Finally, manufacturing in the factory makes it possible to obtain plasters of optimal composition. However, for cost and management reasons, factory manufacturing involves the production of standard size panels.

Although there are different standard dimensions, both in length and width and thickness, it is often necessary to cut these panels to fit the widths and lengths of the walls or ceiling of the room to be equipped.

This cut, made on the site to the appropriate dimensions, must be fast and as sharp as possible to allow easy positioning of two panels contiguously.

Conventionally, this cut consists of "marking" the panel with a cutter blade to cut the first sheet of cardboard and groove the layer of plaster. Then, the operator exerts a stress on the panel so that the plaster layer breaks in two parts along the groove. Finally, the operator cuts the second sheet of cardboard with his cutter to release the two panel parts.

Subsequently, a finish must be achieved by filling the gap between two adjacent plaster boards, using a filler such as plaster or ready-to-use plaster. Once deposited, this filler is smoothed with a knife to coat.

The finishing step must be as fast as possible. For that, it is necessary to limit the number of gestures to be carried out by the user. Clear cutting of the panels would not only limit the amount of filling product used, but also the number of actions to be performed to smooth the surface on and in the vicinity of the gap.

Several solutions exist to make a cutting guide.

The simplest is to use a rule, preferably metal, and hold it in position while the panel is grooved with the cutter.

However, maintaining the ruler may sometimes be insufficient to counter the force applied against the ruler by the grooving movement of the cutter.

This solution is dangerous for the operator since the cutter can slip and injure the user. In addition, these slips lead to a non-rectilinear grooving, so that the resulting cut is irregular: the longitudinal cut is not rectilinear and the cutting edge obtained has many protuberances.

One solution is to provide the guide holding means on the plaster board. In general, these holding means take the form of a clamp fastening firmly the guide on the panel.

This has two major disadvantages. The first is that the maintenance depends on the firmness of the clamping, so that to ensure effective maintenance, it is necessary to strongly tighten the clamps on the panel. This being a relatively friable material, the faces of the panel are necessarily marked and damaged by this clamping. It is therefore necessary, during finishing, to catch these markings by filling them with filling material. However, the arrangement and the size of the clamps generally used to obtain effective maintenance of the guide lead to make markings in particularly large areas and remote from the cutting edge obtained later. The finish must therefore include a specific step of filling these markings, independent of the filling of the space between two consecutive panels.

The second disadvantage lies in the time required to position the guide. Thus, it is first necessary to position the guide along the previously drawn cutting line, then tighten the clamps. This clamping often generates slight changes in position which requires loosening and repositioning of the guide. This system is therefore long to implement, impractical and may damage the faces of the plasterboard.

This is why such systems are very rarely used in practice.

The object of the present invention is therefore to provide a rapid cutting guide solution to implement, and does not require a particular finishing step to reseal the surface of the plasterboard plate.

For this, the invention proposes to decouple the guide and the guide holding means on the plasterboard board.

To this end, the subject of the invention is a cutting guide of a plasterboard board and having two longitudinal edges and two ends, for guiding, in use, a cutting blade parallel to the guide, characterized in that it comprises, at least at one end, a rotatably mounted abutment and provided with means for holding the stop against the plasterboard board.

Thus, thanks to the guide according to the invention, the maintenance of the guide on the panel is located on a panel edge, and not on one side of the panel. sign. In addition, fixing the abutment on the panel is prior to the positioning of the guide along the cutting line and allows angular positioning of the guide after fixing the abutment on the panel.

According to other embodiments:

The stop may comprise two parts connected to each other by a hinge, the two hinged parts being provided with holding means of the gypsum board, the hinge comprising an end stop;

• end stop rotation can allow relative rotation of articulated parts up to 45 degrees, preferably up to 30 degrees;

• The holding means may comprise a profile adapted to maintain the panel when it is inserted in force in the profile;

The holding means may be points intended to be stuck in the plaster board;

The holding means can be retractable;

• the guide may comprise holding means disposed on a surface of the guide intended to be in contact with the plasterboard board to be cut; these holding means may be spikes;

• the guide may further comprise a rail adapted to cooperate slidably, in use, with a carriage provided with the cutting blade;

The guide may comprise, on either side of the rail, solid areas of contact with the board of plasterboard to be cut;

The guide may furthermore comprise, at at least one of its ends, a retractable stop means for enabling, in use, the coupling and decoupling of the rail with a carriage provided with the cutting blade; • the guide may comprise, at least one of its ends, a damping means, in use, the sliding end of stroke of a carriage provided with the cutting blade;

The tips may be arranged so that, in use, after cutting the plaster board, the holes formed by the points planted in the plaster board are located at a determined distance (d) from the cut, sufficient so that the holes are plugged together with a junction between two panels of plasterboard; and or

The determined distance can be between 75 mm and 150 mm, preferably between 70 mm and 120 mm, advantageously between 55 mm and 80 mm, typically 65 mm.

The invention also relates to a cutting kit, comprising:

a guide according to the invention;

a cutting blade comprising at least one grooving wedge having a flat face and a beveled face, extended by at least one leveling edge having a plane face and a bevelled face identical to those of the wedge;

a cutting carriage comprising a frame provided with:

Sliding means of cooperation, in use, with the cutting guide;

A handle, mounted rotatably relative to the frame, and comprising a gripping means, a housing for a cutting blade and a retractable engagement claw;

• A profile provided with at least three locking notches in rotation of the handle in three angular positions by a reversible engagement of the retractable claw, the notches being arranged on the profile so as to allow, in use: for the first notch, a retracted disposition of the blade out of contact with the plaster board;

for the second notch, an arrangement of the blade at an angle with the plasterboard board, in sufficient contact with the plaster board to groove it to form a cutting edge;

> For the third notch, an arrangement of the blade at an angle β with the plaster board, in sufficient contact with the plasterboard board to trim the cutting edge.

The invention also relates to a method of implementing a guide according to the invention, for cutting a board of plasterboard, comprising the following steps:

a) providing a plaster board comprising a layer of plaster and at least one sheet of cardboard or paper;

b) arranging the rotatably mounted abutment against an edge of the plasterboard and activating the abutment holding means to maintain the abutment with respect to the plasterboard board; c) pivoting the cutting guide for disposal along the 'a desired cutting direction

d) press the fence against the plaster board; and

e) groove the panel along the guide with a cutting blade.

According to other embodiments:

Step d) may consist in driving into the plasterboard board points placed on a surface of the guide intended to be in contact with the plasterboard panel to be cut; and or

Step e) can comprise the following steps:

e1) cooperating a carriage carrying the cutting blade with the guide rail; e2) moving the carriage to groove the plaster layer along the guide, from the first edge of the panel to the second edge of the panel;

e3) folding the panel along the groove obtained in the preceding step to break the plaster layer along the groove and obtain a cutting edge;

e4) moving the carriage using the gripping means to the first edge of the panel;

e5) moving the carriage to trim the cutting edge, from the first edge of the panel to the second edge of the panel, the step e2) and / or the step e5) comprising a cutting of at least one sheet of cardboard or paper board plasterboard.

Other features of the invention will be set forth in the detailed description below, made with reference to the appended figures which represent, respectively:

Figures 1 and 1a, partial schematic perspective views of two embodiments of an end of a cutting guide according to the invention;

FIG. 2 is a diagrammatic plan view of a step of implementing a cutting guide according to the invention;

Figures 3 and 4 are schematic perspective views of two embodiments of an end of a cutting guide according to the invention; Figure 5 is a schematic perspective view from below, with respect to the use position, of a cutting guide according to the invention;

Figure 6 is a partial enlargement in perspective of Figure 5 showing a first embodiment of the guide holding means according to the invention on the plaster board;

Figure 7 is a schematic perspective view of a second embodiment of the guide holding means according to the invention on the plasterboard board; Figure 8 is a partial schematic perspective view of a cutting guide according to the invention having a rail for cooperation with a carriage;

Figure 9 is a partial schematic perspective view of a cutting guide according to the invention having a rail provided with a retractable stop means;

Figure 10 is a partial schematic perspective view of a cutting guide according to the invention having a rail provided with a slipping end damping means of a carriage;

- Figure 1 1, a schematic left side perspective view of an embodiment of a carriage according to the invention;

FIGS. 12 to 16 are diagrammatic perspective views of a method for implementing a blank with a guide according to the invention, FIG. 17 is a schematic plan view of a first embodiment of a cutting blade;

Figure 17a is a schematic plan view of a variant of the blade of Figure 17;

Figure 18 is a schematic sectional view along the line XVIII-XVIII of the blade of Figure 7;

- Figure 19, schematic plan views of a second embodiment of a cutting blade.

A cutting guide according to the invention has two longitudinal edges 200a and two ends 200b. The cutting guide is intended to guide, in use, a cutting blade parallel to the guide. According to the invention the guide comprises, at least one end 200b, a stop 210 rotatably mounted relative to the guide and provided with holding means 2 1 of the stop against the plasterboard board.

In the embodiment illustrated in Figure 1, the holding means comprises a tip 21 1 intended to be planted in the thickness of the plasterboard board. Thus, the user has the stop 210 against an edge of the plaster board, and maintains this stop against this panel by pressing the tip 21 1 into the thickness of the plasterboard. Then, since the stop 210 is rotatably mounted relative to the guide 200, it can angularly position, according to its choice, the guide on the plaster board as illustrated in FIG. 2.

The holding means can be retractable. For example, a tip 21 1 is carried by a screw.

Another embodiment illustrated in FIG. 1 a consists in providing, in place of the tip (s) (or screw), a blade perpendicular to the plasterboard panel. This blade is preferably triangular to penetrate the plasterboard panel from below the panel, so that the notch made will not be visible during the installation of the panel.

Preferably, the rotational mounting of the abutment 210 relative to the rail 201 can be controlled using a wheel 212.

With the guide according to the invention, the maintenance depends on the firmness of a clamping on the faces of the plaster board, but on the edge. The faces of the panel are never marked or damaged by this clamping, and it is not necessary, during finishing, to make up the markings present on the edge since they are not visible during assembly.

In addition, retaining means penetrating into the plasterboard panel prevent lateral sliding of the abutment during cutting.

Moreover, the time required to position the guide is decreased compared to known systems. The angular positioning of the guide according to the invention, along the cutting line previously drawn, is subsequent to the fixing of the guide on the panel. This system is therefore quick to implement.

According to a particularly interesting mode, the stop 210 according to the invention comprises two parts connected to one another by a hinge. This embodiment is illustrated in FIGS. 3 and 4. In these figures, the stop 220 comprises a portion 221 similar to the stop 210 of FIG. 1, and a portion 222 connected to the portion 221 by a hinge 223. The two articulated portions 221 and 222 are provided with holding means 21 plaster board. In FIG. 3, the means for holding the articulated part 222 comprise tips 21 1. In FIG. 4, these holding means comprise a plate 21 1 arranged to allow the strength of the plaster board to be maintained between this plate 21 1 a and a protuberance 21 1 b of the articulated part 222. This arrangement can be obtained by producing the hinged portion 222 in a single profiled structure.

The abutment 210 advantageously comprises a stop end rotation allowing a limited rotation of the articulated portions 221 and 222. In practice, the end stop rotation advantageously limits the rotation between 0 and 45 degrees, and preferably between 0 and 30 degrees .

Thanks to these articulated parts, by means of holding the plasterboard board, and the end stop rotation, the user can make a single cut of a board of plasterboard large without risk that the Fall 504 (see Figures 17 and 18) falls during cutting, thus tearing the bottom sheet of paper and / or breaking.

Indeed, when the user breaks the panel along the groove (see Figure 15) and begins the leveling of the cutting edge (see Figures 17 and 18) the end of the already released chute 504 is maintained by the party articulated 222.

Preferably, the cutting guide according to the invention may have holding means disposed on the face 208 intended to be in contact with the gypsum board. As illustrated in FIGS. 5 to 7, these holding means may comprise points intended to be stuck in the plaster of the plaster board.

Thus, when the user has positioned the guide in the desired manner, it suffices to press this guide so that the tips of the holding means are planted in the panel and avoid that, during the various cutting steps (see Figures 14 to 18) the guide moves from its position of use.

In the embodiment of FIG. 7, the tips are carried by rods 209b.

Advantageously, the holding means are retractable to prevent that, when the guide is not used, the tips do not hurt the user. In the embodiment of Figures 5 and 6, these points are carried by screws 209a. When the user wants to use the guide, he takes the screws out of the plane of the surface 208, with a screwdriver. When the user has finished cutting, he unscrews the screws until they come out of the plane of the surface 208.

Any other means that can make the tips retractable can be used in the guide according to the invention.

In these embodiments (retractable tips or not), the panel is called "self fixing" since its simple application against the plasterboard board is enough to block it in the cutting position. In this case, the user has no other action to perform to block the guide.

Preferably, the holding means 209 are arranged on the face 208 of the guide so that, in use, after the cutting of the plasterboard, the holes formed by the points planted in the plasterboard board are located at a distance from one another. determined distance d of the cut, sufficient so that the holes are closed together with a junction between two panels of plasterboard.

For example, the holding means 209 are arranged at the distance d from the edge 200a of the guide.

Conventionally, the finishes are carried out using a coating knife with a width of between 150 mm and 300 mm.

Thus, the tips of the holding means will preferably be arranged at a determined distance of between 75 mm and 150 mm, preferably between 70 mm and 120 mm, advantageously between 55 mm and 80 mm, typically 65 mm. The holes formed by the tips are arranged in an area particularly close to the cutting edge, so that the finish does not need to include a specific step of filling these holes, independent of the filling of the space between two consecutive panels .

The holding means carried by the face of the guide intended to come into contact with the plasterboard panel may also be constituted by a groove in which is slidably mounted a clamp or a clamping abutment. As soon as the user has positioned the guide, it is sufficient for him to slide the clamp or the stop in the groove and to apply it in force against the plaster board, so as to block the guide in the position of use.

The holding means carried by the face of the guide intended to come into contact with the gypsum board may also be constituted by a pair of magnets. One of the magnets being disposed in a groove carried by said face of the guide. This magnet may be continuous, all along the groove, or consist of a multitude of unit magnets arranged, preferably regularly, in the groove along the guide.

As soon as the user has positioned the guide, it is sufficient for him to position a second magnet under the plate, facing the guide and the first magnet, which thus blocks the guide in the cutting position.

In these two last embodiments (clamp or abutment and pair of magnets), the guide is not strictly self-fixing since the user must activate these holding means after positioning the guide. Nevertheless, such a guide is much easier to set up and maintain in position than the current solution of placing the guide and then to position two clamps at the ends of the guide. The cutting guide according to the invention advantageously comprises means for slidingly cooperating with a cutting carriage. For this purpose, the cutting guide comprises a profiled rail such as that illustrated in FIG. 8. In a particularly advantageous embodiment, the guide 200 has a profiled rail 201, intended to cooperate with the wheels 102 of a carriage (see Figure 1 1), this rail 201 being extended laterally by flat areas 202 increasing the contact surface between the guide and the plaster board and the stability of the guide on the panel.

The rail 201 can have any type of shape. A particularly advantageous form, illustrated in FIG. 8, allows better stability and better sliding retention of the carriage according to the invention. Around a longitudinal groove 203, the rail 201 comprises two longitudinal protuberances 204. Each of these protuberances has a portion 201a intended to cooperate slidably with the wheels 102 of the carriage 100. Each portion 201 comprises two non-coplanar rectilinear faces 205-206 connected by a solid 207 substantially perpendicular to the contact face 208 of the guide 200 with the board of plasterboard.

Holding screws 209a are preferably inserted in the longitudinal groove 203. Advantageously, these screws 209a have a length such that, when they are not screwed, they are held in the groove 203 and prevent the carriage from cooperating with the rail.

The flat areas 202 preferably have a width L2 adjusted so that, in use, the cutting blade 300 is in tangential contact with the longitudinal edge 200a of one of the flat areas 202. Thanks to this, the user can easily position the guide since it suffices to make coincide the edge of the solid area and the marking line of the cutout previously drawn by the user. In addition, the contact between the solid 202 and the blade prevents it from oscillating under the action of the movement of the carriage.

According to another embodiment illustrated in FIG. 9, the rail of the guide may comprise a retractable stopping means 230 to allow, in use, the coupling and the decoupling of the rail with the trolley. Thus, when the carriage is coupled to the rail, the retractable stop means prevents, in the movement, the carriage from the rail. After use, for ease of transport, it is desirable to decouple the carriage and rail. The user then deactivate the retractable stop means and remove the carriage from the rail. For example, it is possible to use as retractable stop means a pin 231 provided with a return means 232.

According to another embodiment illustrated in FIG. 10, it is also possible, alternately or in combination, to provide at least one of the ends of the rail with a damping means 240, in use, of the sliding of the carriage at the end. race. Thus, the truck can not violently hit the retractable stop means or, the truck can not come out of the rail violently. For example, a spring or a piston may be used as damping means.

Figure 1 1 illustrates an embodiment of a cutting carriage of a plasterboard panel used with a guide according to the invention. The carriage 100 comprises a frame 101 provided with means for slidingly cooperating with a cutting guide 200. The cooperation means are, in this embodiment, rollers 102 provided with a groove 102a intended to receive a portion 201 a d a rail 201 carried by the guide 200.

The rollers 102 make it possible to slide the frame 101 along the rail 201.

The frame 101 comprises a handle 1 10 rotatably mounted relative to the frame 101. The handle comprises a gripping means 1 1 1 constituted, in this embodiment, by a profiled handle.

The handle also comprises a housing 1 12 for a cutting blade 300.

The frame 101 also comprises a profile 120 provided with three notches A, B and C. These notches are designed to lock the handle 1 10 in rotation by engaging a retractable claw 13 carried by the handle. Advantageously, the retractable engagement claw is coupled to a trigger 1 15 connected to a tension spring 1 14 pressing the claw towards the bottom of the notches. In this way, the user who holds the handle 110 by the handle 111 can retract the claw 113 out of the notch in which it is engaged (here the notch B) by pulling, with a finger of the hand placed on the 111, the trigger 115, against the tension spring 1 4. It can then rotate the handle 110 relative to the frame 101 until the claw 113 snaps into another notch A or C.

Thanks to the profile 120 and the notches A, B and C, the handle can be positioned in a preset manner in three angular positions by reversible engagement of the retractable claw 113 in the notches.

These notches are arranged on the profile, so as to allow, in use:

for the first notch A, an arrangement of the blade 12 out of contact with the plaster board;

- For the second notch B, a provision of the blade at an angle with a board of plasterboard, in sufficient contact with the panel to groove to form a cutting edge (see Figures 15 and 16);

- For the third notch C, a provision of the blade 300 at an angle β with the plasterboard board, in sufficient contact with the panel to trim the cutting edge (see Figures 18 and 19) and cut a possible sheet of paper or cardboard carried by the underside of the panel (the lower face being the opposite side to that carrying the guide 200 and / or the carriage 100).

Preferably, the carriage 100 further comprises a guard 130 of the blade 300, when the claw 113 is engaged in the first notch A. In this position, the blade is out of contact with the plasterboard board. . This position is, advantageously, a secure transport position in which the blade is inaccessible to the user who can not injure himself with the blade.

Thanks to the profile 120 provided with notches, the angular positions of the handle are predetermined and preset. So the user does not need to pay attention to the angle of the blade with respect to the plaster board. He just has to go from one notch to another to get the different positions of the blade. His only concern is to move the guide relative to the panel.

Figures 12 to 16 illustrate the operation of the carriage according to the invention described above.

On a plaster board 500, a cutting guide 200 is positioned along the cutting direction desired by the user. Before or after this positioning, the user slidably cooperates with the carriage 100 with the cutting guide 200.

Once the guide is positioned, the user places the carriage at a first edge 500a of the panel 500. In FIG. 12, the first edge is located on the left; this provision is suitable for implementation by a right-handed user. This first edge is that which is on the side of the slide of the carriage and opposite the handle of the handle. Then, the user actuates the retractable engagement claw to remove it from the notch A of the transport position and rotate the handle until the claw snaps into the second notch B, so that the blade is in sufficient contact with the panel to groove it. The user then moves the carriage in the direction of the arrow F1, by pulling the carriage, from the first edge 500a of the panel 500 to the second edge 500b of the panel 500. During this movement, according to the arrow F1, the The blade makes a groove 501 in the plaster layer of the panel 500. If this layer of plaster is covered with a sheet of paper or cardboard, the blade cuts this sheet at the same time as it grooves the plaster.

During this movement, the only concern of the user is to pull the carriage between the two edges of the panel to groove and cut this panel. He does not have to worry about the position of the blade or its inclination. Thanks to the notch B of the carriage, the groove is perfectly regular both in its shape along the panel and in its depth. Once, arrived at the second edge 500b of the panel, the user folds the panel along the groove obtained in the previous step to break the plaster layer along the groove. This folding in the direction of the arrows F2 (see Figure 13) provides a cutting edge 502 shown in Figure 14. Due to the perfect straightness of the groove, the resulting cutting edge is much more regular than the songs of cut obtained by the cutter cutting process.

To further improve the flatness of this cutting edge, the carriage according to the invention proposes a position of the handle, and therefore of the blade, which makes it possible to trim the cutting edge 502. For this, as illustrated in FIG. the user moves the carriage using the gripping means from the second edge of the panel to the first edge of the panel, according to the arrow F3, then actuates the retractable engagement claw to remove it from the second notch B and pivoting the handle until the claw snaps into the third notch C. In this position, the blade has a flush edge applied against the cutting edge obtained in the folding step of the panel. The user moves the carriage again from the first edge 500a to the second edge 500b, so that the cutting edge is leveled by the blade. This step is illustrated in Figures 15 and 16. The latter figure 16 shows the unmounted cutting edge 502 on the right of the figure and a cutting edge 502a flush left of the figure. Of course, the cutting edge 503 of the chute 504 of the panel 500 is not leveled during this step.

At the same time that the blade edges the cutting edge, it also cuts, if it is present, the sheet of paper or cardboard placed on the underside of the plaster board.

During this movement, the user does not have to worry about the position of the blade which is preset by the arrangement of the notch C. This angular position of the third notch C depends on the thickness of the cardboard panel -plaster. In the example shown, the third notch C is spaced from the second notch B to allow the recessing of a cutting edge of a plaster board with a thickness e1 (see Figure 16).

Advantageously, the carriage may comprise at least one additional notch (for example notches D and E) spaced from the third notch C to allow the leveling of a cutting edge of a plasterboard board with a thickness of e2 or e3 different from the thickness e1 can be leveled when the trigger is engaged in the slot C. The skilled person can provide as many notches as necessary, depending on the number of panel thicknesses to be cut by the carriage according to the invention. For example, notch C might allow the edge of a 10mm thick plaster board to be trimmed, a D notch could be used to trim the edge of a 13mm thick panel (typically called , in France, "panel BA13"), and a notch E could allow the leveling of the cutting edge of a panel 15mm thick. Other notches could be provided for other thicknesses.

The use of a guide according to the invention, previously described, is particularly effective when a blade according to Figures 17 to 19 is used.

Unlike the cutter blade comprising a doubly beveled cutting edge, the cutting blade 300 comprises at least one grooving wedge 301 having, in section, a planar face 300a and a bevelled face 300b (see FIG. 18). The corner is defined by, on one side, a flat face, and on the other side, by a bevelled face having two bevelled edges 308. The two bevelled edges 308 are connected by at least one connecting line 309.

This particular shape of the cutting edge of the blade ensures a perfectly straight grooving by preventing the blade from oscillating during grooving, contrary to what is observed with a cutter blade.

If the blade used is in accordance with that shown in FIGS. 12 to 14, it is preferably the planar face of the blade that is preferentially applied against the edge 200a of the solid 202, and not the beveled face. This reinforces the guiding of the blade by optimizing the contact surface between the blade and the guide.

The bevelled face allows the cutting of the first sheet of cardboard and the grooving of the plaster layer, and the flat face keeps the blade in the same position during the grooving of the plaster. The inventor has found that it is this maintenance of the position of the blade perpendicular to the plasterboard board that allows to obtain a perfectly straight groove and a cutting edge much more regular than when using cutter blades. These being bevelled on each face, it is very difficult, even impossible, even with a guide, to keep the blade in position, so that these cutter blades hunt and the cutting edge obtained later is very irregular.

The best results have been obtained with an angle γ, between the flat face and the bevelled face, between 15 and 25 degrees, and preferably an angle γ of 20 degrees. Thus, when the bevel has such an angle, the blade remains perfectly straight and does not oscillate during grooving. In addition, the grooving obtained has a depth and a shape such that when the user folds the board of plasterboard (as in Figure 8), the edge obtained is much more regular than that obtained with a cutter blade.

To further improve the regularity and flatness of the cutting edge, the blade further comprises a leveling edge 302 also having a flat face and a bevelled face. The leveling edge 302 has a length L1 greater than or equal to the thickness of the gypsum board. If this thickness is denoted e, the length L1 of the leveling edge must be greater than or equal to: e / sinus β, where β is the angle between the blade and the plasterboard when the trigger is engaged in the third notch C of the carriage (see Figures 15 and 16). Of course, when the carriage comprises more than three notches, the length L1 of the edge the level of the gypsum board divided by the smallest angle β of these notches.

In a particularly advantageous embodiment, the blade comprises between the grooving wedge 301 and the leveling edge 302, a cutting notch 303. This notch is useful when the plasterboard board comprises a sheet of paper or cardboard on the underside of the plaster board, in the cutting position. Thus during the step of leveling the cutting edge, this sheet of paper or cardboard is engaged in the notch 303 which allows clean and clean cutting of the sheet and prevents this sheet to be simply torn. Advantageously, to facilitate this cutting, the cutting notch is curved.

The concomitance of the leveling of the cutting edge and the cutting of the lower sheet of paper makes it possible to obtain a cut plasterboard board, none of the sheets of paper being torn and whose cutting edge is without any protuberance and perfectly parallel to the used carriage guide (so perfectly straight if the guide is a straight ruler).

The juxtaposition of several panels of plasterboard is optimized, and the amount of filling materials for finishing is greatly limited. In addition, the fact that the sheets of paper or cardboard are not torn off, avoids having to fill the irregularities on the surface of the board of plasterboard.

The blade has a hole 315 intended to cooperate with a bolt provided with a nut 1 12a disposed in the housing 1 12 for receiving the blade of the carriage 100. The blade 310 also comprises holes 316 intended to cooperate with fixed rods arranged in the housing 1 2 to maintain the blade and prevent it from pivoting around the bolt 1 12a. Of course, any other means for fixing the blade in the housing can be used, as long as this fastening means firmly holds the blade perpendicularly to the plaster board. In this way, with a blade according to the invention, the planar face 300a of the blade 300 is held perpendicular to the plaster board during grooving and leveling.

FIG. 17a illustrates a variant of the blade of FIG. 7. In this variant, the grooving wedge 301 has a connecting face 307 between the two beveled edges 308 of the grooving wedge.

The connecting face 307 is delimited by two connecting lines 309, as well as by a connecting line 309c with the bevelled face 300b. The connecting face 307-317a-317b forms a plane forming an angle δ with the plane face 300a. The angle δ is smaller than the angle γ of the beveled edges 308 with the flat face 300a. Advantageously, the angle δ is between 10 and 20, and preferably an angle δ of 15 degrees. The preferred embodiment is an angle γ of 20 degrees and an angle δ of 15 degrees.

The connection face 307-317a-317b facilitates the penetration of the blade in the plasterboard during grooving and limits the forces during the maneuver. In addition, the inventor has found that the effort that is exerted on the fall to break the plasterboard is also limited.

Indeed, the connecting face 307 very substantially improves the groove obtained during the grooving step (see Figure 12). When the connection face is absent, the single connecting line 309 can rub strongly against the plaster and tear off small pieces of plaster and paper or cardboard during the grooving. The groove may therefore sometimes, especially when the grooving is very fast, abrasions that induce, when the panel is folded (see Figure 13), a not regular cutting edge. The connecting face 307 limits the friction between the grooving wedge and the panel, so that the groove obtained is particularly regular. It has almost no scratch. The resulting cutting edge is very regular and has very few protrusions, and projections of small sizes. The subsequent step of leveling is therefore facilitated and is only a finish to obtain a perfectly flat cutting edge, without any annoying projection for the positioning of two panels against each other.

This variant is applicable to the embodiment illustrated in FIG. 19.

In general on a construction site, it is necessary to carry out many cuts of boards of plasterboard. All these cuts wear the blade, so that it can, during the cutting movements (see Figures 12 to 16) become dull. The grooving is therefore no longer straight and, when the user folds the cardboard panel (see Figure 13), the cutting edge may no longer be perfectly parallel to the guide and may have a large irregularity (presence of many protuberances). It is therefore necessary to change blades.

An embodiment of a particularly advantageous blade is illustrated in FIG. 19. In this embodiment, the four corners of the plate constituting the blade are used as grooving wedges. Each of these corners is extended by a leveling edge. Between each corner and the leveling edge, the blade carries a cutting notch. In this embodiment, two diametrically opposite grooving wedges 311a-311a are symmetrical with respect to the center of the rectangular plate constituting the blade 310. On the other hand, two consecutive grooving wedges 311a-311b have a flat face and an opposite beveled face. . This means, as illustrated in FIG. 19, that a grooving wedge 311a has a beveled upper face and a flat lower face. In contrast, a grooving wedge 311b has a flat top face and a beveled bottom face. It is the same for the other structures that are the leveling edges 312a and 312b and notches 313a and 3b cutouts.

The embodiment of Fig. 19 allows the two groove wedges 311a to be used by pivoting the blade around the hole 315 and using the two grooving wedges 311b to turn the blade. Thus, with the same blade 310, four zones of grooving and leveling are obtained can be used successively when one of these areas is worn.

In alternative embodiments not shown, the blade may bear only one, two or three zones each comprising a grooving corner, a leveling edge and a cutting notch.

In another embodiment not illustrated, the blade is suitable for both left-handed and right-handed users. This blade has, for example, four grooving corners, four edges and four cutting notches. In this embodiment, two diametrically opposed grooving corners are symmetrical with respect to the center of the rectangular plate and two consecutive grooving corners have the same plane face and the same beveled face. With this embodiment, it is possible to manufacture a blade that can be used either from left to right or from right to left.

To this end, it can be provided that the cutting carriage according to the invention is removable and can be configured for either a right-handed person or a left-handed person. Thus, the profile carrying the notches and the handle can be fixed on both sides of the frame. When there is a protective cover, it is also expected that this hood can be removed and fixed either for a right-handed person or for a left-handed person. Figure 11 illustrates an arrangement suitable for implementation by a right-handed user.

Of course, it is possible to provide only one cutting area for a right-handed and only one cutting zone for a left-handed person.

Claims

1. A guide (200) for cutting a board of plasterboard and having two longitudinal edges (200a) and two ends (200b), for guiding, in use, a blade (300, 310) cutting parallel to the guide, comprising, at at least one end (200b), a stop (210, 220) rotatably mounted and provided with holding means (21 1, 21 1a) of the stop against the plaster board, characterized in that it comprises holding means (209, 209, 209b) disposed on a surface (208) of the guide intended to be in contact with the plasterboard panel to be cut.

2. Guide according to the preceding claim, wherein the holding means are spikes.

3. Guide according to claim 1 or 2, wherein the stop (220) comprises two parts (221, 222) connected to one another by a hinge (223), the two hinged parts being provided with holding means (21 1, 21 1a) of the gypsum board, the hinge comprising a stop end rotation.

4. Guide according to claim 3, wherein the end stop rotation allows relative rotation of the articulated parts up to 45 degrees, preferably up to 30 degrees.

5. Guide according to any one of claims 1 to 4, wherein the holding means comprises a profile adapted to maintain the panel when it is inserted in force in the profile.

6. Guide according to any one of claims 1 to 4, wherein the holding means are points intended to be planted in the plasterboard panel.

7. Guide according to the preceding claim, wherein the holding means are retractable.

8. Guide according to any one of claims 1 to 7, further comprising a rail (201) adapted to slidably cooperate, in use, with a carriage (100) provided with the cutting blade (300, 310 ).

9. Guide according to the preceding claim, comprising, on either side of the rail (201) contact solids (202) with the plasterboard board to cut

10. Guide according to any one of claims 8 or 9, further comprising, at least one of its ends (200b), a retractable stop means (230, 231-232) to allow, in use coupling and decoupling the rail with a carriage provided with the cutting blade.

11. Guide according to any one of claims 8 to 10, comprising, at least one of its ends (220b), damping means (240), in use, the sliding end of stroke of a trolley with cutting blade.

12. Guide according to any one of claims 7 to 11, wherein the tips are arranged so that, in use, after cutting the plaster board, the holes formed by the points planted in the cardboard panel- plaster are located at a determined distance (d) from the cut, sufficient so that the holes are plugged together with a junction between two panels of plasterboard.

13. Guide according to the preceding claim, wherein the determined distance (d) is between 75 mm and 150 mm, preferably between 70 mm and 120 mm, preferably between 55 mm and 80 mm, typically 65 mm.

14. Cutting kit of a plasterboard board comprising:

a guide according to any one of claims 8 to 13; a cutting blade (300, 310) comprising at least one grooving wedge (301, 311a, 311b) having a flat face and a beveled face, extended by at least one leveling edge (302, 312a, 312b) presenting a flat face and a bevelled face identical to those of the corner;

a cutting carriage (100) comprising a frame (101) provided with:

Means (102) for slidably cooperating in use with the cutting guide;

A handle (110), rotatably mounted relative to the frame (101), and comprising a gripping means (111), a retractable engagement claw (113) and a housing (112) for a cutting blade ( 300, 310);

• a profile (120) provided with at least three notches (A, B, C) for locking the handle in three angular positions by a reversible engagement of the retractable claw, the notches being arranged on the profile so as to allow , in use :

for the first notch (A), a retracted disposition of the blade out of contact with the plaster board;

for the second notch (B), an arrangement of the blade at an angle with the plaster board, in sufficient contact with the plaster board to groove it to form a cutting edge;

for the third notch (C), an arrangement of the blade at an angle β with the plaster board, in sufficient contact with the board of plasterboard to trim the cutting edge.

15. A method of implementing a guide according to any one of claims 1 to 13, for cutting a board of plasterboard, characterized in that it comprises the following steps: a) providing a gypsum board (500) comprising a gypsum layer and at least one sheet of cardboard or paper;

b) arranging the stop (210, 220) rotatably mounted against an edge of the gypsum board and activate the holding means (211, 211a) of the stop to maintain the stop against the gypsum board;

c) pivoting the cutting guide to arrange it along a desired cutting direction;

d) press the fence against the plaster board; and

e) groove the panel along the guide with a cutting blade.

16. A method of implementation according to the preceding claim, wherein step d) consists in driving into the plasterboard panel spikes arranged on a surface of the guide intended to be in contact with the plasterboard board to cut.

17. Method of implementation according to any one of claims 15 or 16, a guide according to any one of claims 8 to 13, wherein step e) comprises the following steps:

e1) cooperating a carriage carrying the cutting blade with the guide rail;

e2) moving the carriage to groove the plaster layer along the guide, from the first edge of the panel to the second edge of the panel;

e5) moving the carriage to trim the cutting edge, from the first edge of the panel to the second edge of the panel, step e2) and / or step e5) comprising cutting at least one sheet of cardboard or paper from the plaster board.