EP2560799A1

EP2560799A1 - Carriage for cutting a sheet of gypsum board, cutting kit and method for implementing same

Info

Publication number: EP2560799A1
Application number: EP11720878A
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: US9067339B2; WO2012020330A1; FR2959155A1; FR2959155B1; US20130126574A1

Abstract

The invention proposes a solution for cutting a sheet of gypsum board quickly and allowing a flat cut edge to be obtained. The invention relates to a carriage comprising a chassis (101) fitted with: - means (102) for collaborating in a sliding manner with a cutting guide (200); - a handle (110) that can rotate with respect of the chassis (101) and comprises a means (111) for grasping, a retractable engagement claw (113) and a housing (112) to hold a blade (300); - a section piece (120) provided with at least three notches (A, B, C) in which to lock the rotation of the handle through reversible engagement of the claw, the notches being arranged such that: • the first notch (A) allows the blade to be retracted so that it is not in contact with the sheet; • the second notch (B) allows the blade to be arranged at an angle α to the sheet of gypsum board, in firm enough contact with the sheet to score it in order to form a cutting edge; • the third notch (C) allows the blade to be arranged at an angle β to the sheet of gypsum board in firm enough contact with the sheet to trim the cutting edge.

Description

CUTTING BOARD OF PLASTER CARDBOARD, CUTTING KIT AND METHOD OF IMPLEMENTING SAME

The invention relates to a cutting cart of a plasterboard board, to a cutting kit and to a method of implementing the kit.

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.

Subsequently, a finish must be achieved by filling the gap between two adjacent plaster boards, using a product of filling such as plaster or plaster ready for use. 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 for cutting a board of plasterboard.

The most common is to "mark" the panel with a cutter blade (a knife blade, known from the state of the art and illustrated in Figure 13, is constituted by a plate having a doubly beveled edge, that is, that is, both faces of the plate are bevelled).

This operation allows the cutting of the first sheet of cardboard and the grooving of the plaster layer. 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. Generally, in this last step, the second sheet of paper is torn off rather than cut, which creates an irregularity on the surface of the plaster board to be filled during the finishing.

This solution is dangerous for the operator because of the use of the cutter. Indeed, the grooving obtained is never rectilinear, even with the use of a guide, and it often happens that the speed of the grooving movement causes a sudden deviation of the blade of the cutter from the guide to the body of the user.

It is for this reason that some societies forbid this practice to their workers. Some public institutions even forbid this practice in their tenders, but in practice this is the most widely used method. Moreover, this solution also has two technical disadvantages. First, the use of a cutter blade generates non-rectilinear grooves so that the breakage along the surface of the panel can take such irregular shapes that a new panel must be used and cut. Second, the cutting edge, obtained after breaking the plaster layer, is still very irregular, in the sense that the cutting edge obtained has many protuberances, even with a long experience of the user. It is difficult to adjust two contiguous panels whose cutting edge is irregular. It is also necessary, during finishing, to use a large quantity of filling material to obtain a perfectly flat surface between the two consecutive panels.

To solve this problem, some operators have proposed a second cutting solution consisting of using a handsaw or jigsaw. The teeth of the blade of this saw must be carefully selected to avoid splinters of plaster and generate an irregular cutting edge. For the same reason, the speed and the cutting frequency must also be adapted, which requires an important know-how.

Well done, this second cutting solution provides a clean cutting edge. Nevertheless, this solution is longer than manual cutting with the cutter. In addition, boards plasterboard thin (less than or equal to 18 millimeters) are unsuitable for the use of a saw. This solution becomes interesting only for thicknesses greater than 20 millimeters because beyond this thickness, the stress to be exerted to break the plaster layer is too great and the breakage does not necessarily follow the groove.

The objective of the present invention is therefore to provide a fast and clean cutting solution of a plasterboard board.

For this, the invention proposes to use a support carriage of a cutting blade, on the one hand, to hold firmly the blade during the grooving so that the break along the surface of the rectilinear panel and, secondly, to achieve a step of leveling the edge of the panel after breaking the plaster layer.

To this end, the invention relates to a cutting carriage of a plasterboard board, the carriage comprising a frame provided with:

sliding means of cooperation, in use, with a cutting guide;

- A handle, rotatably mounted 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 board of plasterboard;

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

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

According to other embodiments:

The retractable engagement claw can be connected to a pressing tension spring, in the rest position, the claw in a notch;

• The carriage may further comprise a blade guard, when the claw is engaged in the first notch.

• the third notch may be spaced from the second notch to allow the leveling of a cutting edge of a board of plasterboard of a first thickness; The carriage may comprise at least one additional notch spaced from the third notch to allow the leveling of a cutting edge of a plasterboard board of at least a second thickness;

The housing may contain 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 flat face and a bevelled face identical to those of the grooving wedge;

The blade may comprise, in addition, at least one cutting notch arranged between the grooving wedge and the leveling edge;

• the beveled face of the blade can make an angle with the flat face between 15 ° and 25 °, preferably 20 °;

• the leveling edge may have a length greater than the thickness of the board of plasterboard;

• the cutting notch can be curved; and or

The blade may be constituted by a rectangular removable plate having two faces and comprising:

- four grooving corners;

- four cutting notches;

- four edges of leveling,

two diametrically opposed grooving wedges being symmetrical with respect to the center of the rectangular plate, two consecutive grooving wedges having opposite flat face and beveled face.

The invention also relates to a cutting kit of a plaster board, comprising:

a carriage according to the invention;

a cutting blade comprising at least one grooving wedge having a flat face and a bevelled face, extended by at least one leveling edge having a plane face and a bevelled face identical to those of the wedge; a cutting guide having two longitudinal edges and two ends, and comprising at least one rail adapted to slidably cooperate, in use, with the carriage provided with the cutting blade for, in use, to guide the cutting blade in a manner parallel to the guide, and comprising, at least at one end of the rail, a rotatably mounted and profiled abutment to maintain, in use, the board of plasterboard.

According to other embodiments:

the cutting kit can include:

a carriage carrying 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 guide having two longitudinal edges and two ends, and comprising at least one rail adapted to slidably cooperate, in use, with the carriage provided with the cutting blade to, in use, guide the cutting blade in a parallel manner to the guide, and comprising, at least at one end of the rail, a rotatably mounted and profiled abutment for maintaining, in use, the plaster board;

the rail and the stop may be provided with means for holding the stop on the plaster board;

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

the guide may further comprise, at at least one of its ends, a retractable stop means for allowing, in use, the coupling and decoupling of the rail with the carriage;

the guide may comprise, at least one of its ends, a damping means, in use, the sliding end of travel of the carriage; and or 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 allowing a relative rotation articulated parts up to 45 degrees, preferably up to 30 degrees.

The invention also relates to a method of implementing a kit 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) slidingly engage the carriage with a cutting guide;

c) arranging the cutting guide between two edges of the panel in a given cutting direction, and placing the carriage at a first edge of the panel;

d) actuating the retractable engagement claw to remove it from the notch in which it is engaged and rotate the handle until the claw can snap into the second notch, so that the groove wedge of the blade is applied to the panel;

e) moving the carriage using the gripping means to groove the plaster layer along the determined cut from the first edge of the panel to the second edge of the panel; f) folding the panel along the groove obtained in the previous step to break the plaster layer along the groove and obtain a cutting edge;

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

h) actuate the retractable engagement claw to remove it from the second notch and rotate the handle until the claw can snap into the third notch, so that the edge flaring is applied against the cutting edge obtained in step f);

i) moving the carriage with the gripping means to level the cutting edge, from the first edge of the panel to the second edge of the panel,

step e) and / or step i) comprising cutting said at least one sheet of cardboard or paper from the plaster board.

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 to 3, schematic views in left side perspective of a first embodiment of a carriage according to the invention in three different cutting positions;

Figures 4 to 6, schematic views in right side perspective of the first embodiment of a carriage according to the invention respectively in the three cutting positions of Figures 1, 2 and 3; Figures 7 to 10, schematic perspective views of an implementation of the cutting method according to the invention;

Figure 1 1, a partial enlargement in perspective of Figure 23 illustrating the surface condition obtained after leveling the edge of the plasterboard board;

Figure 12 is a schematic left side perspective view of a second embodiment of a carriage according to the invention;

Figure 13 is a schematic sectional view of a cutter blade illustrating the state of the art;

Figure 14 is a schematic plan view of a first embodiment of a blade according to the invention;

Figure 14a, a schematic plan view of a variant of the blade of Figure 14;

- Figure 15, a schematic sectional view along line XV-XV of the blade of Figure 14; Figures 16 and 17 are schematic plan views of two embodiments of a blade according to the invention;

Figure 18 is a partial schematic perspective view of the blade of Figure 17;

Figures 19 to 21, schematic plan views of three other embodiments of a blade according to the invention;

Figure 22 is a partial schematic perspective view from above, with respect to the use position, of a cutting guide according to the invention;

Figure 23 is a schematic perspective view from below, with respect to the position of use, a cutting guide according to the invention;

Figure 24, a partial perspective enlargement of Figure 23 showing a first embodiment of the guide holding means according to the invention on the plaster board;

Figure 25 is a schematic perspective view of a second embodiment of the guide holding means according to the invention on the plaster board;

Figures 26 to 28 are schematic perspective views of three embodiments of an end of a cutting guide according to the invention; and

Figure 29 is a schematic plan view of a step of implementing a cutting guide according to the invention. Figure 1 illustrates a first embodiment of a cutting carriage of a plasterboard board 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. Such a guide will be described in more detail in connection with FIG. 22. 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 (see Figures 2 and 3) for a cutting blade 300.

The frame 101 also comprises a profile 120 provided with three notches A, B and C. These notches are intended to lock in rotation the handle 1 10 through the engagement of a retractable claw 1 13 carried by the handle. Advantageously, the retractable engagement claw 1 13 is connected to a tension spring 1 14 pressing the claw towards the bottom of the notches. Preferably, the claw 13 is actuated by a trigger 15.

In this way, the user who holds the handle 1 10 by the handle 1 1 1 can retract the claw 1 13 out of the notch in which it is engaged (here the notch A) by pulling, with a finger of the placed on the handle 1 1 1, the trigger 1 15, against the tension spring 1 14. It can then rotate the handle 1 10 relative to the frame 101 until the claw 1 13 engages in another notch B (see Figure 2) or C (see Figure 3).

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 1 13 in the notches.

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

- For the first notch A, a provision of the blade 1 12 out of contact with the plasterboard board (see Figure 1 and 4);

for the second notch B, a provision of the blade at an angle with a board of plasterboard, in sufficient contact with this panel to groove it to form a cutting edge (see Figures 2, 5 and 7) ; - For the third notch C, a provision of the blade 300 at an angle β with the board of plasterboard, in sufficient contact with this panel to trim the cutting edge (see Figures 3, 6, 10 and 1 1).

Preferably, the carriage 100 further comprises a protective casing 130 of the blade 300, when the claw 1 13 is engaged in the first notch A. In this position, the blade is out of contact with the cardboard panel. plaster. 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.

Figures 4 to 6 illustrate the cutting carriage illustrated in Figures 1 to 3, but seen from the opposite side relative to the profile 120.

In Figure 4, the handle 1 10 is in the transport position shown in Figure 1. The blade 300 carried by the sleeve is protected by the housing 130 and is therefore not visible in FIG.

In Figure 5, the handle 1 10 is in the position shown in Figure 2, that is to say, that the claw 1 13 is engaged in the notch B (not visible in Figure 5). In this position, the blade 300 carried by the handle 10 forms an angle with the gypsum board 500. The blade is in sufficient contact with the panel 500 to groove it to form a cutting edge. This step will be described in more detail in connection with FIG.

In FIG. 6, the handle 1 10 is in the same position as that illustrated in FIG. 3, that is to say that the claw 1 13 is engaged in the notch C. In this position, the blade 300 carried by the handle 1 10 forms an angle β with the gypsum board 500. In this manner, the blade is in sufficient contact with the gypsum board 500 to trim the cutting edge and, advantageously, cut the sheet of paper or cardboard carried by the underside of the panel (the lower face being the face opposite that which carries the guide 200 and / or the carriage 100.

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 blade relative to the panel.

Figures 7 to 1 1 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. 7, the first edge is located on the left; this provision is suitable for implementation by a right-handed user. This first edge is the one on the side of the blade 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 this, the groove is perfectly regular as much in its shape along the panel as 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 arrows F2 (see Figure 8) provides a cutting edge 502 shown in Figure 9. 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. 9, 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 FIGS. 10 and 11. The latter Figure 1 1 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 11).

Advantageously, as illustrated in FIG. 12, the carriage comprises at least one additional notch (the notches D and E) spaced apart from the third notch C to allow the leveling of a cutting edge of a plasterboard board. thickness e2 or e3 different thickness e1 can be leveled when the trigger is engaged in the notch C. In Figure 12, two additional notches are provided but, of course, the skilled person can predict that other depending on the number of panel thicknesses to be cut by the carriage according to the invention. For example, the notch C could allow to screed the edge of a board of plasterboard 10mm thick, the notch D could allow to screed the edge of a panel of 13mm thick (classically called, in France, "panel BA13") and the notch E could allow the trimming of the cutting edge of a panel of 15mm thick. Other notches could be provided for other thicknesses.

The implementation described above is particularly effective when, according to the invention, a blade according to Figures 14 to 21 is used with the carriage.

In contrast to the cutter blade illustrated in FIG. 13 and comprising a doubly beveled cutting edge, the carriage according to the invention advantageously contains a cutting blade 300 comprising at least one grooving wedge 301 having, in section, a planar face 300a and a bevelled face 300b (see Figure 15). 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. 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 beveled 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 Figure 6). Of course, when the carriage comprises more than three notches (see Figure 12), the length L1 of the leveling edge must be greater than or equal to the thickness of the gypsum board divided by the sinus of the smallest angle β notches C, D or E.

Figure 14a illustrates a variant of the blade of Figure 14. 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 connection facet 307 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 connecting face 307 facilitates the penetration of the blade into 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 substantially improves the groove obtained during the grooving step (see Figure 7). 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 present, especially when the grooving is very fast, abrasions which induce, when the panel is folded (see Figure 8), 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 thus 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 embodiments illustrated in Figures 16 to 21. In a particularly interesting embodiment illustrated in FIG. 16, the blade comprises between the grooving wedge 301 and the leveling edge 302, a cutting notch 303. This notch is useful when the plasterboard panel comprises a sheet of paper or cardboard on the underside of the plasterboard, 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 plasterboard panels cut with the aid of the trolley according to the invention is therefore optimized, and the quantity 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.

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 7 to 10) become dull. The grooving is therefore no longer straight and, when the user folds the cardboard panel (see Figure 8) 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 FIGS. 17 and 18. In this embodiment, the four corners of the plate constituting the blade are used as wedges of grooving. 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 31a-31a are symmetrical about the center of the rectangular plate constituting the blade 310. On the other hand, two consecutive grooving wedges 31a-31b present a flat face and an opposite beveled face. This means, as illustrated in FIG. 18, that a grooving wedge 31 1 has a beveled upper face and a flat lower face. On the contrary, a grooving corner 31 1b has a planar upper face and a beveled lower face. The same goes for the other structures that are the leveling edges 312a and 312b and the notches cutouts 313a and 313b.

According to the invention, the blade has a hole 315 intended to cooperate with a bolt provided with a nut January 12a (see Figure 1 1) disposed in the housing 1 12 for receiving the blade of the carriage 100. The blade 310 also comprises holes 316 for cooperating with fixed rods disposed in the housing 1 12 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.

The embodiment of FIG. 17 makes it possible to use the two grooving wedges 31a by pivoting the blade around the hole 315 and to use the two grooving wedges 31b to turn the blade. Thus, with the same blade 310, four grooving and leveling zones are obtained that can be used successively when one of these zones is worn. Of course, as shown in Figures 19 and 20, the blade may have only two zones each comprising a grooving wedge, a leveling edge and a cutting notch.

Figure 21 illustrates another embodiment of a blade according to the invention, suitable for both left-handed and right-handed users. This blade 320 has four grooving wedges 321, four leveling edges 322 and four cutting notches 323. In this embodiment, two diametrically opposite grooving wedges are symmetrical with respect to the center of the rectangular plate and two grooving wedges. consecutive have the same plane face and the same bevelled 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. Figures 1 to 6 illustrate an arrangement suitable for implementation by a right-handed user.

In the embodiment of Figure 21, the four corners are used to provide, to a right-handed and left-handed, two cutting areas that can be used successively when the first to be used is worn. 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.

The cutting carriage according to the invention advantageously comprises means for slidingly cooperating with a cutting guide. A particularly adapted cutting guide has a profiled rail like that illustrated in FIG. 22. In accordance with the invention, the guide of the carriage has two longitudinal edges 200a and two ends 200b. In a particularly advantageous embodiment, the guide 200 has a profiled rail 201, intended to cooperate with the wheels 102 of the carriage (see Figures 1 and 22), this rail 201 being extended laterally by flat areas 202 increasing the contact area between the guide and the board of plasterboard.

The rail 201 can have any type of shape. A particularly advantageous form, illustrated in Figure 22, allows better stability and better sliding support 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 straight non-coplanar faces 205-206 connected by a solid 207 substantially perpendicular to the contact face 208 of the guide 200 with the board of plasterboard.

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. If the blade used is in accordance with the invention, it is the flat face of the blade which is preferably applied against the solid surface 202, and not the bevelled face. This further enhances the guiding of the blade by optimizing the contact area between the blade and the guide.

Preferably, the cutting guide according to the invention may have holding means 209 disposed on the face 208 intended to be in contact with the plasterboard board. As illustrated in FIGS. 23 to 25, 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 prevent, during the various cutting steps (see Figures 7 to 10) the guide moves from its position of use.

In the embodiment of FIG. 25, 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 23 and 24, these points are carried by screws 209a. The screws are preferably inserted into the longitudinal groove 203. 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 his cuts, he unscrews the screws until they come out of the plane of the surface 208. Advantageously, these screws have a length such that, when they are not screwed, they are maintained in the groove 203 and prevent the carriage from cooperating with the rail.

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

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 solid surface 202.

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 between 75 mm and 150 mm, preferably between 70 mm and 120 mm, advantageously between 55 mm and 80 mm, typically 65 mm.

Advantageously, the cutting guide comprises, at least at one end 200b of the rail 201, a stop 210 rotatably mounted relative to the rail 201. Advantageously, the stop is provided with holding means, in use, against the board of plasterboard. In the embodiment illustrated in FIG. 26, this holding means comprises a point 21 1 intended to be stuck in the thickness of the plasterboard. Thus, the user has the abutment 210 against an edge of the plaster board, and maintains this abutment against this panel by pushing the tip 21 1 in the thickness of the gypsum board. Then, since the stop 210 is rotatably mounted relative to the rail 201, it can angularly position at its choice the guide on the gypsum board as shown in Figure 29.

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

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

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 Figures 27 and 28.

In these figures, the stop 220 comprises a portion 221 similar to the stop 210 of FIG. 26, and a portion 222 connected to the portion

221 by a hinge 223. The two hinged parts 221 and 222 are provided with holding means 21 1 of the gypsum board. On the face

27, the holding means of the hinged portion 222 comprise tips 21 1. In Figure 28, these holding means comprise a plate 21 1 arranged to allow the maintenance, in force, the plasterboard board between this plate 21 1 a and a protrusion 21 1 b of the hinged portion 222. This arrangement can be obtained by realizing the articulated part

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 FIG. 11) does not fall during the leveling step, thus tearing the bottom sheet of paper and / or breaking.

Indeed, when the user breaks the panel along the groove (see Figure 8) and begins the leveling of the cutting edge (see Figures 10 and 11) the end of the already released chute 504 is maintained by the party articulated 222.

According to other embodiments not illustrated, the rail of the guide may comprise a retractable stop means to allow in use, the coupling and decoupling of the rail with the carriage. 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 deactivates the retractable stop means and removes the carriage from the rail. For example, it is possible to use as retractable stop means a pin provided with a return means.

It is also possible, alternately or in combination, to provide at least one end of the rail with a damping means, in use, the sliding of the carriage at the end of the 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.

Claims

1. A cutting trolley of a plasterboard board characterized in that it comprises a frame (01) provided with:

means (102) for slidingly cooperating, in use, with a cutting guide (200);

- 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 receiving, in use, a cutting blade (300);

- A profile (120) provided with at least three notches (A, B, C) for locking 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), a retracted disposition of the blade out of contact with the plaster board;

For the second notch (B), arranging the blade at an angle with the gypsum board (500), in sufficient contact with the gypsum board to groove it to form a cutting edge (502);

For the third notch (C), an arrangement of the blade at an angle β with the plaster board (500), in sufficient contact with the plaster board to trim the cutting edge (502a).

2. Trolley according to claim 1, wherein the retractable engagement claw is connected to a tension spring (114) urging, in the rest position, the claw (113) in a notch (A, B, C).

3. Trolley according to any one of claims 1 or 2, further comprising a protective housing (130) of the blade, when the claw (113) is engaged in the first notch (A).

4. Trolley according to any one of claims 1 to

3, wherein the third notch (C) is spaced from the second notch (B) to allow the leveling of a cutting edge of a plasterboard board of a first thickness (e1).

5. Trolley according to any one of claims 1 to

4, comprising at least one additional notch (D, E) spaced from the third notch (C) to allow the leveling of a cutting edge of a plasterboard board of at least a second thickness (e2, e3).

6. Trolley according to any one of claims 1 to 5, wherein the housing (1 12) contains a cutting blade (300, 310) comprising at least one grooving wedge (301, 31 1) having a flat face ( 300a) and a bevelled face (300b), extended by at least one leveling edge (302, 312) having a planar face (300a) and a bevelled face (300b) identical to those of the grooving wedge (301).

The trolley according to claim 6, wherein the blade further comprises at least one cutting notch (303,313) arranged between the grooving wedge (301,31 1) and the leveling edge (302,312). .

8. Trolley according to any one of claims 6 or

7, wherein the beveled face (300b) of the blade makes an angle (γ) with the flat face (300a) between 15 ° and 25 °, preferably 20 °.

9. Trolley according to any one of claims 6 to

8, wherein the leveling edge (302, 312) has a length (L1) greater than the thickness (e1, e2, e3) of the gypsum board.

10. Trolley according to any one of claims 7 to 9, wherein the cutting notch (303, 313) is curved.

11. Trolley according to any one of claims 7 to 10, wherein the blade (310) is constituted by a rectangular removable plate having two faces and comprising:

four grooving wedges (31 a, 311 b);

four cutting notches (313a, 313b);

four alignment edges (312a, 312b), two diametrically opposite grooving wedges (31a-31a) being symmetrical with respect to the center of the rectangular plate, two consecutive grooving wedges (31a-31b) having an opposite flat face and beveled face.

12. Kit for cutting a plasterboard board comprising:

- a carriage (100) according to any one of claims 1 to 5;

- a cutting blade (300, 310) comprising at least one grooving wedge (301, 31 1) having a flat face and a beveled face, extended by at least one leveling edge (302, 312) having a flat face and a bevelled face identical to those of the corner;

- A cutting guide (200) having two longitudinal edges (200a) and two ends (200b), and comprising at least one rail (201) adapted to cooperate in a sliding manner, in use, with the carriage provided with the cutting blade for, in use, guiding the cutting blade parallel to the guide, and comprising, at least at one end of the rail, a stop (210, 220) rotatably mounted and profiled to maintain, in use, the board of plasterboard .

13. Kit for cutting a plasterboard board comprising:

- A carriage according to any one of claims 6 to 1 1;

14. Cutting kit according to any one of claims 12 or 13, wherein the rail (201) and the stop (210, 220) are provided with holding means (209, 209a, 209b, 211, 211a) of the abutment on the plaster board.

15. Cutting kit according to claim 14, wherein the holding means are points intended to be planted in the plasterboard panel.

16. Cutting kit according to any one of claims 12 to 15, wherein the guide further comprises, at at least one of its ends, a retractable stop means to allow, in use, the coupling and the decoupling of the rail with the trolley.

17. Cutting kit according to any one of 12 to 16, wherein the guide comprises, at least one of its ends, a damping means, in use, the sliding end of travel of the carriage.

18. Cutting kit according to any one of claims 12 to 17, wherein the stop (220) comprises two parts (221, 222) connected to one another by a hinge (223), the two articulated parts. being provided with holding means (211, 211a) of the gypsum board, the hinge (2232) comprising an end stop allowing a relative rotation of the articulated parts up to 45 degrees, preferably up to 30 degrees.

19. A method of implementing a kit according to any one of claims 12 to 18, 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) slidingly engage the carriage (100) with the cutting guide (200);

c) arranging the cutting guide between two edges of the panel in a given cutting direction, and placing the carriage at a first edge of the panel; d) actuate the retractable engagement claw to remove it from the notch in which it is engaged and rotate the handle until the claw engages in the second notch (B), so that the wedge grooving the blade is applied to the panel;

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

h) actuate the retractable locking claw to remove it from the second notch (B) and rotate the handle until the claw engages in the third notch (C), so that the edge of leveling is applied against the cutting edge obtained in step f);