Band clamp tool with seal

Abstract

The invention provides a tool (20) for clamping joint tape, comprising a scraper blade (22) having a front scraper edge (24) and being fixed to a blade holder (28) over at least 70% of the transverse working width, the tool (20) comprising a stiffener (40) which • is affixed against the scraper blade (22); • has a rear portion (44, 45) arranged between the scraper blade (22) and the blade holder (52); • has a front edge (46) which is arranged behind the front scraper edge (24) of the scraper blade (22) and set back rearwardly relative to the front scraper edge (24) by an amount in the range of 0 to 30 millimeters; • has a maximum width in the range of 30 to 120 millimeters.

Description

Technical Field

[0001] The present invention relates to the field of tools for the implementation of plasterboards for the creation of partitions or for the cladding of walls or ceilings in the construction field. The present invention relates more particularly to a joint tape tightening tool. Technical background

[0002] For many years now, plasterboard has been used to create partitions or to cover walls or ceilings in the construction industry. To cover a wall or ceiling, or to form a partition, several plasterboards are used, arranged side by side. Two adjacent plasterboards are positioned edge to edge, and a joint is created between the two boards to join them together and make the junction of the two boards invisible.

[0003] It has been illustrated on the Figure 1a method of making a joint between two plasterboards, according to the technique of the prior art. On this Figure 1 , two plasterboards 10a, 10b are illustrated which are arranged next to each other, and which are joined at a respective edge 12a, 12b. In the example, the plasterboards 10a, 10b have a thinned edge 13a, 13b.

[0004] To cover the gap between the two respective edges 12a, 12b, the craftsman covers the gap with a quantity of coating 15 and applies, on the coating, along the gap, a joint strip 17, generally made of paper, over the entire length of the two respective edges 12a, 12b, the joint strip 17 being arranged astride the gap. To ensure good fixing of the joint strip 17, the craftsman carries out the operation known as “tightening” (or sometimes called “gluing”) of the joint strip 17 which consists, using a first knife 14 of the type of plastering knife or smoothing knife, having a width slightly greater than the width of the joint strip 17, in firmly pressing the joint strip astride the two contiguous plasterboards 10a, 10b, over the gap between the two respective edges 12a, 12b of the two plasterboards 10a, 10b.In doing so, a quantity of excess coating 18, located under the passage of the first knife 14, is expelled laterally perpendicular to the extension of the joint strip 17.

[0005] In a second operation, the craftsman preferably uses a second smoothing knife 16, the width of which is greater than the width of the first knife 14, to scrape off the excess plaster 18 which has been pushed out perpendicularly beyond the limits of the joint strip 17. When the two adjoining plasterboards 10a, 10b are boards with a thinned edge, the two thinned edges 13a, 13b form a depression 19 along the joint strip 17 which has a width greater than that of the joint strip 17. In such a case, the width of the second knife 16 is preferably chosen to be greater than the width of the depression 19. Preferably, the excess plaster 18 is thus smoothed to avoid any excess plaster thickness in the joint area.

[0006] This proven technique requires the use of two tools in two successive operations. In practice, the craftsman sometimes forgoes using a second tool and uses the first tool, which requires him, due to the narrow width of the first tool, to multiply the passes for the "tightening" operation to cover the entire width. This lengthens the duration of the operation and does not promote the creation of a perfectly smooth joint, without marks. The aim of the invention is to propose a tool that simplifies the operations of "tightening" the joint tape and scraping off the excess coating, while maintaining an exemplary quality of finish for the joint thus created. Statement of the invention

[0007] For this purpose, the invention provides a joint tape clamping tool, comprising a scraper blade which extends in a longitudinal direction and a transverse direction perpendicular to each other, the scraper blade having a front scraper edge which extends in the transverse direction and which has a transverse working width greater than or equal to 180 millimeters, the scraper blade being fixed, by a rear area of ​​the scraper blade, to a blade support, according to a blade connection.

[0008] The tool is characterized in that the blade connection extends over a transverse width representing at least 70% of the transverse working width, in that the joint strip clamping tool comprises a stiffener which: is affixed against an upper face of the scraper blade; has a rear portion which is arranged between the upper face of the scraper blade and a lower face of the blade holder; has a front edge which is arranged in front of a front edge of the blade holder and behind the front scraping edge of the scraper blade; has a maximum width in the transverse direction which is in the range of 30 to 120 millimeters;

[0009] The tool is further characterized in that the front edge of the stiffener is arranged to be set back longitudinally rearwardly relative to the front scraping edge of the scraping blade by a longitudinal setback value in the range of 0 to 30 millimeters.

[0010] In some examples, the stiffener is formed from a plate element separate from the scraper blade. This makes it possible to implement elements that are capable of being manufactured industrially at low cost and with very good repeatability of the mechanical characteristics of the elements, therefore perfect control of the quality of the tool in use. In such examples, the scraper blade may be formed from a plate element having a thickness in the range from 0.2 to 2 millimeters, and in that the plate element of the stiffener has a thickness of between 50% and 400% of the thickness of the plate element of the scraper blade, more preferably between 100% and 250% of the thickness of the plate element of the scraper blade 22.Such value ranges allow to obtain a deformation behavior of the scraping blade and the stiffener which allows the user to obtain the effect of “tightening” and scraping with a natural feeling for the user.

[0011] In some examples, the stiffener is arranged transversely across the center of the scraper blade, symmetrically about a median longitudinal axis of the scraper blade. Such a symmetrical tool exhibits symmetrical behavior well suited to the symmetrical nature of most joint configurations between two plasterboards.

[0012] In some examples, the front edge of the stiffener has a convex profile. Such a profile contributes to a gradual change in the overall longitudinal bending stiffness profile of the tool when moving transversely away from the median longitudinal axis. This avoids abrupt stiffness transitions at the front scraping edge of the scraping blade, thereby preventing the formation of corresponding traces on the coating.

[0013] In some examples, the front edge of the stiffener is, at each of its transverse ends, connected to lateral edges of the stiffener by rounded transverse ends. Such a feature also limits the presence of abrupt stiffness transitions at the front scraping edge of the scraping blade.

[0014] In some examples, the stiffener is attached to the scraper blade in an attachment area that is arranged, in the longitudinal direction, in the rear half of the length of the stiffener in the longitudinal direction. With this feature, at least the front half of the stiffener can slide longitudinally on the scraper blade when these two elements are, in use, deformed in longitudinal bending, by shearing effect, which contributes to a more progressive stiffening of the tool.

[0015] In some examples, the scraping blade and the stiffener are made of metal in order to obtain, at low cost, a tool offering a good compromise between weight, thickness and stiffness of the blade as well as good resistance over time, guaranteeing the longevity of the tool.

[0016] In some examples, the scraper blade and the stiffener are fixed to each other by welding or gluing, that is to say with techniques allowing fixing without elements appearing in the external faces of the assembly, elements likely to generate accumulations of coating during application.

[0017] In some examples, the blade holder includes a front sole having a bottom face and a rear heel, and the scraper blade and stiffener are attached to the bottom face of the front sole, forward of the rear heel. The scraper blade and stiffener are attached together to the blade holder.

[0018] In other examples, the blade holder includes a front sole having a bottom face and a rear heel having a bottom face, and the scraper blade and stiffener are attached to the bottom face of the rear heel, and extend forwardly opposite the bottom face of the front sole. In still other examples, the blade holder includes a front sole having a bottom face and a rear heel having a forwardly open housing, and the scraper blade and stiffener are attached to the blade holder by a rear region of the scraper blade that is engaged in the housing of the rear heel. Here too, the scraper blade and stiffener are attached together to the blade holder. In such examples, in which the scraper blade and stiffener are free relative to the sole, the front sole may have a front edge that bears on an upper face of the stiffener.This makes it possible to reproduce a usual gesture of the experienced user of a traditional smoothing knife when, in addition to holding the traditional tool by its usual grip area, he exerts pressure directly on the smoothing blade with the tips of his fingers.

[0019] In some examples, the scraper blade and the stiffener are attached to the blade support by double-sided adhesive pads arranged on the upper face of the scraper blade transversely on either side of the stiffener, outside the perimeter of the stiffener. Such an attachment is easy to implement industrially. In some such examples, the double-sided adhesive pads may have a thickness greater than or equal to the thickness of the stiffener so that the stiffener does not prevent contact between the adhesive pads and the support. Brief description of the drawings

[0020] [ Fig. 1 ] : There Figure 1is a schematic perspective view of a technique for making a joint between two plasterboards, according to the prior art. Fig. 2 ] : There Figure 2 is a perspective view of a first embodiment of a joint tape clamping tool. Fig. 3 ] : There Figure 3 is a perspective view of the first embodiment of Figure 2, from another angle. Fig. 4 ] : There Figure 4 is a perspective view of a scraper blade provided with a stiffener. Fig. 5 ] : There Figure 5 is an exploded perspective view of the first embodiment of the Figure 2 . [ Fig. 6 ] : There Figure 6 is a perspective view of a second embodiment of a joint tape clamping tool. Fig. 7 ] : There Figure 7 is a partial sectional view of the second embodiment of the Figure 6 . [ Fig. 8 ] : There Figure 8is a sectional view of a third embodiment of a joint tape clamping tool. Fig. 9 ] : There Figure 9 is a sectional view of a fourth embodiment of a joint tape clamping tool [ Fig. 10 ] : There Figure 10 is a sectional view of a fifth embodiment of a joint tape clamping tool. Detailed description

[0021] It has been illustrated on the Figures 2 to 5 a first embodiment of a joint strip clamping tool 20. Advantageously, the joint strip clamping tool 20 makes it possible to carry out, during the same pass, both the operation of “clamping” the joint strip (sometimes called the operation of “gluing” the joint strip), and the operation of scraping the quantity of excess coating 18 which is expelled laterally relative to the joint strip 17 by the “clamping” operation.

[0022] Generally, the joint strip clamping tool 20 comprises a scraper blade 22 which extends in a longitudinal direction X and a transverse direction Y perpendicular to each other. A direction Z, arbitrarily called vertical, is also defined, perpendicular to the longitudinal direction X and to the transverse direction Y. Arbitrarily, a forward direction of the longitudinal direction is defined, which is indicated by the orientation of the arrow X of the Figure 2 as opposed to a direction behind the longitudinal direction. Arbitrarily, a direction above or towards the top of the vertical direction Z is defined, which is indicated by the orientation of the arrow Z of the Figure 2 , as opposed to a lower or downward direction of the vertical Z direction.

[0023] The scraper blade 22 can be considered to be generally planar, although it may have a slight bulge, as will be described later. The scraper blade 22 is generally formed from a plate element which extends in the longitudinal direction X and the transverse direction Y and which has a thickness in the vertical direction Z.

[0024] Preferably, the scraping blade 22 is made of metal, for example stainless steel. However, other materials may be considered for producing the scraping blade 22, including polymer materials, in particular polymer materials loaded with reinforcing fibers or particles, in particular beads and / or fibers, in particular glass, talc and / or carbon.

[0025] The scraping blade 22 has a front scraping edge 24 which extends in the transverse direction Y and which has a transverse working width greater than or equal to 180 millimeters. The transverse working width is the dimension, in the transverse direction Y, of the contact between the front scraping edge 24 and a flat surface representing a plasterboard, under normal conditions of use of the tool 70, in particular in terms of force applied to the tool and orientation of the scraping blade relative to the flat surface. Such a transverse working width therefore makes it possible to carry out in a single pass the operation of scraping the quantity of excess coating 18 likely to escape laterally during the simultaneous operation of "tightening" the joint strip 17.It also allows the front scraping edge 24 to bear, at each of its lateral ends 25, on unthinned portions of each of the two juxtaposed plasterboards, in order to have these unthinned portions as an altitude reference for scraping the coating. The transverse working width of the front scraping edge 24 is preferably less than or equal to 1000 millimeters, more preferably less than or equal to 500 millimeters, in order not to overflow unnecessarily onto the central zones of the plasterboards 10a, 10b, at a distance from the joint zone.

[0026] The scraper blade 22 is fixed, by a rear zone 26 of the scraper blade 22, to a blade support 28, according to a blade connection extending over a transverse width representing at least 70% of the transverse working width. It is understood here that the scraper blade 22 is fixed in abutment on the support at at least two points which are distant from each other, in the transverse direction Y, by a distance representing at least 70% of the transverse working width. The fixing of the scraper blade 22 on the support can be continuous between these two extreme points, or can be discontinuous, in the sense that discrete fixing points can be distributed between these two extreme points. This makes it possible in particular to limit the twisting of the scraper blade 22 around the longitudinal direction X in the case where a non-symmetrical force is applied to the tool 20.From a kinematic point of view, the blade connection is a connection analogous to a recess, which eliminates all degrees of freedom between the scraper blade 22 and the blade support 28.

[0027] In the illustrated example, the scraper blade 22 is of rectangular geometry, elongated with a larger dimension in the transverse direction Y compared to its dimension in the longitudinal direction X. However, the scraper blade 22 could have a trapezoidal or similar geometry, with the limitation, however, that the rear zone 26 of the scraper blade 22 must have a sufficient dimension so that the blade connection with the blade support 28 extends over a transverse width representing at least 70% of the transverse working width.

[0028] In the illustrated example, the front edge 24 of the scraper blade 22 has rounded lateral ends 25. In the example, these rounded lateral ends 25 are connected to lateral edges of the scraper blade 22 which, in this example, are rectilinear and oriented in the longitudinal direction X.

[0029] In the illustrated examples, the blade holder 28 is part of a tool body 30. In the first exemplary embodiment illustrated in the Figures 2 to 5, the tool body 30 has a gripping zone 32. It will be seen that the tool body 30, and in particular the gripping zone 32, can take various configurations. The gripping zone 32 can be a gripping zone adapted to manual gripping, which the user can grasp with his hands to manipulate the tool, and / or can be a mechanical gripping zone, for example with an interface zone with a tool handle. However, in all cases, the blade support 28 has, in the transverse direction, a transverse width representing at least 70% of the transverse working width of the front scraping edge 24. The blade support 28 also has, in the longitudinal direction X, a sufficient dimension to allow effective and reliable fixing of the scraping blade 22.

[0030] Preferably, the tool body 30 and therefore the blade support 28 are bodies that are rigid with respect to the forces applied during normal use of the tool 20, that is to say, exhibiting negligible deformations under the application of such forces.

[0031] For example, for the first example of realization illustrated on the Figures 2 to 5 , or for the second embodiment illustrated on the Figures 6 and 7 , or for the third embodiment of the Figure 8, the tool body 30 may be formed from an extruded profile, the extrusion direction being the transverse direction Y, with the possibility of closing the profile at the two transverse ends by caps 34 of suitable shapes. In such a case, the tool body 30 therefore has a constant cross-section over its entire transverse width. The tool body 30 could be a solid body, but, in the first, second and third exemplary embodiments, it is a body having internal recesses which extend along the transverse direction Y of extrusion, with internal members which provide the tool body 30 with its rigidity.

[0032] In the first embodiment, the tool body 30 has, in cross-section, an S-shaped profile, the lower half of which forms a tool foot 34 comprising a front sole 36 and a heel 38, and an upper part of which forms the gripping zone 32. The gripping zone 32 has a front part joining with the heel 38 of the tool foot 34, and a rear wing which extends longitudinally towards the rear. The tool body 30 is therefore identical or similar to that of a smoothing tool marketed by the applicant under the trade name “L'outil Parfait - ParfaitLiss' ®<”. The gripping zone, in this embodiment, forms both a particularly ergonomic manual gripping zone, and also a mechanical gripping zone allowing a handle, or pole, to be fixed in a simple and reliable manner, which allows the user of the tool to work on joints placed at height.In this embodiment, the tool foot 34 forms the blade support 28.

[0033] Generally, the scraper blade 22 is fixed against a lower face of the blade support 28, to be integral with the blade support 28. On the other hand, the scraper blade 22 extends longitudinally forward beyond a front edge 29 of the blade support 28. Thus, the scraper blade 22 has a front zone 27, which ends longitudinally forward by the front scraper edge 24 and which projects longitudinally forward relative to the blade support 28. Preferably, the scraper blade 22 projects longitudinally forward relative to the blade support 28 by a minimum overhang value of at least 10 millimeters, the minimum overhang value being the minimum longitudinal distance, observed over the transverse width of the scraper blade 22, between a point of the front scraper edge 24 and the longitudinally aligned point of the front edge 29 of the blade support 28.The front zone 27 of the scraping blade is therefore likely to flex vertically upwards when the scraping blade 22, in particular its front transverse edge 34, is applied against the plasterboard(s) which border the joint, while a downward force is applied to the tool 20 via the gripping zone 32.

[0034] The joint tape clamping tool 20 comprises a stiffener 40 which cooperates with the scraper blade 22 to modify the flexural stiffness properties thereof.

[0035] In the examples illustrated in the Figures, the stiffener 40 is formed from a plate element separate from the scraper blade 24, preferably a plate element of constant thickness. Thus, the stiffener 40 can be produced particularly economically, for example by cutting. In addition, producing the stiffener 40 in the form of a plate element of constant thickness makes it possible to easily obtain, when using the tool 20, a longitudinal bending deformation profile of the stiffener 40 which harmoniously follows that of the front zone 27 of the scraper blade 22. Longitudinal bending is understood to mean a progressive deformation in the vertical direction Z, a deformation which is a function of the longitudinal position of the point considered on the object affected by said longitudinal bending.However, it could be envisaged that the stiffener 40 is produced in a single piece with the scraper blade, the assembly being produced in whole or in part for example by molding, by machining and / or by additive manufacturing, for example by 3D printing of the stiffener 40 on the scraper blade 22. Similarly, the stiffener 40 could be produced in the form of a three-dimensional, non-flat part or part of parts.

[0036] The stiffener 40 extends parallel to the scraping blade 22. The stiffener 40 is placed against an upper face 42 of the scraping blade 22. At rest, that is to say in the absence of force applied to the tool, the stiffener 40 is preferably in contact over its entire surface with the upper face 42 of the scraping blade 22.

[0037] The stiffener 28 is also preferably fixed, directly or indirectly, to the support 28, preferably by a connection similar to a recess, which eliminates all degrees of freedom between the stiffener 40 and the blade support 28, while leaving a front portion of the stiffener 40 free to deform relative to the blade support 28. As illustrated in Figure 5 , the stiffener 40 is separate from the blade support 28.

[0038] The stiffener 40 has a rear portion 44 which is arranged between the upper face 42 of the scraper blade 22 and a lower face of the blade support 28, and which is therefore embedded relative to the blade support. In the first and second examples, the rear portion 44 of the stiffener 40 is arranged in correspondence with the rear zone 26 of the scraper blade 22. In the first and second examples illustrated, but not necessarily, the stiffener 40 has a rear edge 45 which is arranged longitudinally at the same level as a rear edge 23 of the scraper blade 22.

[0039] The stiffener 40 has a front edge 46 which, in the longitudinal direction, is arranged in front of a front edge 29 of the blade support 28 and at or behind the front scraping edge 24 of the scraper blade 22. It is thus possible to define, for the stiffener 40, a front overhang zone 48 which extends in front of the front edge 29 of the blade support 28. This front overhang zone 48 is therefore a front part of the stiffener 40 which is free to deform relative to the blade support 28. Preferably, the stiffener 40 projects longitudinally forward relative to the blade support 28 by an overhang value of at least 5 millimeters, preferably at least 10 millimeters, the overhang value being the maximum longitudinal distance, observed over the transverse width of the scraper blade 22, between a point on the front edge 46 of the stiffener 40 and the longitudinally aligned point of the front edge 29 of the blade holder 28.

[0040] Preferably, the stiffener 40 is arranged transversely to the center of the scraper blade 22. In particular, it is advantageously arranged symmetrically with respect to a median longitudinal axis A1 of the scraper blade 22, so that the stiffening effect provided by the stiffener 40 is symmetrical along the transverse direction Y on either side of the median longitudinal axis A1.

[0041] The stiffener 40 has a maximum width in the transverse direction Y which is in the range from 30 to 120 millimeters. In the example, the stiffener 40 has a constant transverse width over its extent in the longitudinal direction X. It thus has opposite lateral edges which are parallel to each other and which extend in the longitudinal direction X from the rear portion 44 to the front edge 46 of the stiffener 40. However, other geometries are possible, not necessarily having a constant width.

[0042] The front edge 46 of the stiffener 40 is arranged longitudinally set back rearwardly relative to the front edge 24 of the scraper blade 22 by a longitudinal setback value that is in the range of 0 to 30 millimeters. In this way, in combination with the fact that the front edge 46 of the stiffener 40 is arranged in front of the front edge 29 of the blade holder 28, the front overhang region 48 of the stiffener 40 approaches close to the front edge 24 of the scraper blade 22 and can influence the stiffness of the front region 27 of the scraper blade 22 in the transverse width portion of the scraper blade 22 that corresponds to the position of the stiffener 40.As a result, in the transverse width portion of the scraper blade 22 which corresponds to the position of the stiffener 40, the scraper blade 22 has a longitudinal bending stiffness which is greater than the longitudinal bending stiffness for the portions of the scraper blade 22 which are situated transversely on either side of the front overhang zone 48 of the stiffener 40.

[0043] In use, the craftsman will use the joint strip tightening tool 20 by sliding the scraper blade 22 against the joint, following the elongate extension of the joint strip 17, and applying to the tool 20 the same type of force as that to which he is accustomed for the joint strip tightening operation, taking care to make the position of the stiffener 40 correspond transversely with the position of the joint strip 17. Due to the difference in stiffness generated by the presence of the stiffener 40, the tool 20 generates a contact pressure on the joint strip 17 which is greater than the contact pressure generated transversely on either side thereof.Thus, by the pressure profile thus automatically generated, it is ensured that the joint strip 17 is properly “tightened”, that the quantity of excess coating 18 is expelled transversely on either side of the two sides of the joint strip 17, and that this quantity of excess coating is properly scraped by the scraping blade 22, all this in a single pass of the tool 20 along the joint strip 17.

[0044] Typically, the scraper blade is formed from a plate element having, in particular when the scraper blade 22 is made of metal, particularly stainless steel, a thickness in the range from 0.2 to 2 millimeters. In such a case, it has appeared optimal to provide that the plate element forming the stiffener 40 has a thickness of between 50% and 400% of the thickness of the plate element of the scraper blade, more preferably between 100% and 250% of the thickness of the plate element of the scraper blade 22, for example a thickness twice that of the thickness of the plate element of the scraper blade 22, in particular when the stiffener 40 is made in the form of a metal plate element, particularly stainless steel.

[0045] In the illustrated examples, the front edge 46 of the stiffener 40 has a convex profile. In the examples, the front edge 46 is curved with a curvature facing longitudinally towards the rear. Preferably, the curvature of the front edge 46 is less than that of a circle having a diameter equal to the maximum transverse width of the stiffener 40. In other words, preferably, the front edge 46 is located longitudinally entirely in front of a circle having a diameter equal to the maximum transverse width of the stiffener 40 and tangent to the front longitudinal end of the stiffener 40. However, the front edge 46 could be rectilinear and transverse in the transverse direction Y. Preferably, the profile of the front edge 46 is symmetrical on either side of the median longitudinal axis A1 of the scraper blade 22.

[0046] In the illustrated examples, the front edge 46 of the stiffener 40 is, at each of its transverse ends, connected to the lateral edges of the stiffener 40 by rounded transverse ends 50.

[0047] The convex profile of the front edge 46 of the stiffener 40, in particular its curvature facing longitudinally towards the rear, contributes to a progressive evolution of the overall stiffness profile in longitudinal bending of the tool 20 when one deviates transversely from the median longitudinal axis A1. The rounded transverse ends 50 also participate in such a progressive evolution of the overall stiffness profile in longitudinal bending.

[0048] In some embodiments, it could be provided that the stiffener 40 is simply placed against the scraper blade 22, without any relative attachment between the two. Alternatively, it could be provided that the stiffener 40 is attached to the scraper blade 22 over the entire contact area of ​​the stiffener 40 with the scraper blade 22, or over a substantial portion thereof, or over the entire or a substantial portion of the longitudinal extension of the stiffener 40.

[0049] However, in the illustrated example, the stiffener 40 is fixed to the scraper blade 22 in a fixing zone which is arranged, in the longitudinal direction, in the rear half of the length of the stiffener 40 in the longitudinal direction, preferably in the rear third of the stiffener 40 in the longitudinal direction. Thus, in front of the fixing zone of the stiffener 40 on the scraper blade 22, the stiffener 40 can slide longitudinally relative to the scraper blade 22, in contact with the latter, when the scraper blade 22 and the stiffener 40 are subjected to longitudinal bending during use of the tool. This longitudinal sliding capacity allows a progressive evolution of the overall stiffness profile in longitudinal bending of the tool 20, and consequently a more “natural” deformation of the tool 20 with respect to the perception by the user.

[0050] Preferably, the scraper blade 22 and the stiffener 40 are both made of metal, preferably both of stainless steel. However, it is possible to provide for associating a scraper blade made of metal, in particular stainless steel, with a stiffener made in whole or in part with other materials, in particular polymer materials, possibly loaded with reinforcing fibers or particles, in particular balls and / or fibers, in particular glass, talc and / or carbon.

[0051] Preferably, the scraper blade 22 and the stiffener 40 are attached to each other by welding or gluing. For example, a scraper blade 22 and a stiffener 40 both made of stainless steel may be joined, in a rear attachment area, by discrete spot welds.

[0052] In the first example of realization illustrated on the Figures 2 to 5, the blade support 28 comprises a front sole 36 having a lower face 52 and a rear heel 38, and the scraper blade 22 and the stiffener 40 are fixed on the lower face 52 of the front sole 36, in front of the rear heel 38. In particular, it can be seen that the rear edge 23 of the scraper blade 22, said rear edge 23 extending transversely, and said rear edge 23 being, in this example, longitudinally at the same level as the rear edge 45 of the stiffener 40, said rear edge 45 of the stiffener also extending transversely, are both arranged in front of a front edge 54 of the heel 38, preferably in contact with this front edge 54 of the heel 38. The heel 38 protrudes downwards relative to the lower face 52 of the front sole 36, and the assembly formed by the scraper blade 22 and stiffener 40 partially compensate for the difference in altitude in the vertical direction Z between the lower face 52 of the front sole and the heel 38.

[0053] In this example, the assembly formed by the scraper blade 22 and the stiffener 40 is fixed to the blade support 28 by double-sided adhesive pads 56. According to an advantageous example as illustrated, these adhesive pads 56 are arranged on the upper face 52 of the scraper blade 22, transversely on either side of the stiffener 40, outside the perimeter of the stiffener 40. In such a configuration, the double-sided adhesive pads 56 advantageously have a thickness greater than or equal to the thickness of the stiffener 40, such that the stiffener 40 does not form an obstacle to perfect contact between the adhesive pads 56 and the lower face 52 of the blade support 28.

[0054] In the example, the double-sided adhesive pads 56 are arranged in the rear area 26 of the scraper blade 22, for example on a rear area 26 corresponding substantially to the rear quarter of the scraper blade 22 in the longitudinal direction. In the example, the double-sided adhesive pads 56 extend longitudinally from the rear edge 23 of the scraper blade 22. In the example, the double-sided adhesive pads 56 extend transversely each respectively to the corresponding lateral edge of the scraper blade 22, thus forming, between the scraper blade 22 and the blade support 28, a blade connection extending over a transverse width representing 100% of the transverse working width in this particular case of a rectangular scraper blade.

[0055] In the second exemplary embodiment of the invention illustrated in the Figures 6 and 7, the scraper blade 22 and the stiffener 40 are identical or similar to what has been described with reference to the first embodiment, so that reference will be made to the above description as to their characteristics. The tool 20 of this second embodiment differs from the first embodiment firstly by the geometry of the gripping zone 32 of the tool body 30. In this case, in this second embodiment, the gripping zone 32 of the tool body 30 is identical or similar to that of the tool which is described for example in the document FR-3.078.354-A1 of the applicant, to which reference may usefully be made for a detailed description of the characteristics and advantages of such a gripping zone 32. It is noted that this gripping zone 32 can serve as a manual gripping zone, or can serve as a mechanical gripping zone, forming an interface zone for a pole system, as described in the document FR-3.078.354-A1.

[0056] In this second embodiment, the blade support 28 comprises, just like the first embodiment, a front sole 36 having a lower face 52 and a rear heel 38 having a lower face 58. Just as in the first embodiment, the heel 38 protrudes downwards relative to the lower face 52 of the front sole 36, behind the latter. In this second embodiment, the scraper blade 22 and the stiffener 40 are fixed on the lower face 58 of the rear heel 38, and extend forwards opposite the lower face 52 of the front sole 36. In this example, the scraper blade 22 and the stiffener 40 are free relative to the front sole 36, and are therefore not fixed to the lower face 52 of the front sole 36.

[0057] According to a particular aspect of this exemplary embodiment, but which is also found in the first embodiment, the heel 38 is in the form of a strip articulated on the tool body 30. For example, the strip forming the heel 38 extends over the entire transverse width of the tool body 30. It has a rear transverse edge, by which it is connected by an articulation to the rest of the tool body 30, and a front transverse edge which, in the absence of external force, bears vertically upwards against a rear part of the lower face 52 of the front sole 36. In the example, the strip forming the heel 38 is integral with the rest of the tool body 30, in particular if the latter is produced in the form of a profile extruded in the transverse direction Y. Thus, there is a flexible connection zone between the rear transverse edge of the strip forming the heel 38 and the rest of the tool body 30.It is understood that, if a vertically downward force is applied to the strip forming the heel 38, the strip 38 can pivot around the articulation of its rear transverse edge, its front transverse edge then moving vertically downward relative to the lower face 52 of the front sole 36. When the operator exerts a force on the tool body 30, while tilting it relative to the surface to be smoothed on which the front edge 34 of the scraping blade 22 is resting, the heel 38 pivots around the articulation and accompanies the bending movement of the scraping blade as its front zone 27 bends longitudinally while tilting upwards.At this time, thanks to the fact that the scraper blade 22 and the stiffener 40 are free relative to the front sole 36, in the sense that they are not fixed to the lower face 52 of the front sole 36, the front edge 54 of the heel 38 can detach from its support on the rear part of the lower face 52 of the front sole 36. This advantageous characteristic of such a method of fixing the scraper blade 22 and the stiffener 40 guarantees a progressive longitudinal bending of the scraper blade 22 over a significant part of its dimension in the longitudinal direction, which greatly improves the scraping of the coating. It should also be noted that, in this embodiment of the . Figures 6 and 7, when the assembly of the scraper blade 22 and the stiffener 40 is bent under the force, the front sole 36, which is rigid, has a reduced contact surface with the scraper blade 22 and the stiffener 40. The front edge 29 of the blade support 28, here constituted by the front edge 29 of the front sole 36, constitutes an intermediate bending edge for the scraper blade 22 and the stiffener 40. In other words, in use, the front edge 29 of the front sole 36 bears on an upper face of the stiffener 40. This support is made in front of and at a distance from the rear fixing parts 26, 44 of the scraper blade 22 and the stiffener 40 on the blade support 28, in an area which, in the longitudinal direction X, is intermediate between these rear fixing parts 26, 44 and the front edge of scraping 24.It is understood that, in such a configuration, it is the entire extent of the scraper blade 22 and the stiffener 40, between the rear fixing parts 26, 44 and the front scraper edge 24, which deforms in bending. On the other hand, the front edge 29 of the front sole 36 forms a bending edge, which is fixed relative to the blade support 28, and which limits the vertical displacement of the front scraper edge 24 relative to the blade support 28. The large longitudinal extent of the area which bends makes it possible to obtain a regular curvature of the scraper blade 22.This front edge 29 of the front sole 36, resting on an upper face of the stiffener 40, reproduces a usual gesture of the experienced user of a traditional smoothing knife when, in addition to holding the traditional tool by its usual gripping zone, he exerts with the end of his fingers a pressure directly on the blade, in an intermediate zone which, in the longitudinal direction X, is intermediate between the blade support and the front scraping edge.

[0058] Preferably, the plane of the lower face 50 of the front sole 36 and the plane of the lower face 58 of the heel 38 form an angle between them so as to present, on either side of the front edge 54 of the heel 38, and in the absence of force exerted on the tool 20, a concavity between the respective lower faces 52, 58 of the front sole 36 and of the heel 38. This makes it possible to promote the assembly formed by the scraping blade 22 and the stiffener 40 being in contact with the front sole 36 only at the level of the front edge 29 thereof. The acute angle β between the two planes is for example in the range from 2 to 20 degrees, preferably from 5 to 10 degrees, which results in a concavity having an open angle, between the respective lower faces 52, 58 of the front sole 36 and the heel 38, in the range from 160 to 178 degrees, preferably from 170 to 175 degrees, around the front edge 54 of the heel 38.

[0059] In a third embodiment, illustrated in Figure 8, the fact is exploited that, just as in the first and second embodiments, the blade support 28 comprises a front sole 36 having a lower face 52 and, behind the front sole, a rear heel heel 38 which defines a housing 60 open towards the front, which can be accessed at the level of the front edge 54 of the heel 38. The scraper blade 22 and the stiffener 40 are fixed by a rear zone 26 of the scraper blade 22 which is engaged in the housing 60 of the rear heel 38. This rear zone 26 can be provided with one or more elastic lugs 62, for example obtained by cutting and folding the corresponding portions of the scraper blade 22, to lock the rear zone 26 of the scraper blade 22 in the housing 60 of the heel 38, thus to lock the scraper blade 22, and indirectly the stiffener 40, on the blade holder 28.The support 28 can advantageously be configured so that the scraper blade 22 and the stiffener 40 are pressed against the lower face 52 of the front sole 36 by the pinching due to the heel 38.

[0060] It will be noted that, in the third embodiment as illustrated in the Figure 8 , the rear area 26 of the scraper blade 22, by which the scraper blade 22 is attached to the blade support 28, extends longitudinally rearwardly behind the rear edge 45 of the stiffener 40. In the example, the rear edge 45 of the stiffener 40 is arranged just behind the front edge 54 of the heel 38, but outside the housing 60. However, provision could be made for a rear portion of the stiffener 40 to also be received inside the housing 60, see that, as in the previous embodiments, the stiffener 40 extends rearwardly to the rear edge 23 of the scraper blade 22.

[0061] Beyond the fixing methods described above to ensure the fixing of the scraper blade 22 on the blade support, those skilled in the art can implement other fixing methods known to those skilled in the field in question, including fixing by screws, rivets, welding, gluing, etc.

[0062] On the Figure 9, a fourth embodiment has been illustrated in which the tool 20 has a tool body 30 whose geometry is substantially that of a coating knife. In this exemplary embodiment, the plane defined by the longitudinal direction X and the longitudinal direction Y of the scraping blade 22 is a plane of symmetry for the tool body 30. The latter therefore comprises a blade support 28 comprising an upper portion 28A and a lower portion 28B, arranged respectively on either side of this plane of symmetry. The rear zone 26 of the scraper blade 22, and the corresponding rear zone of the stiffener 40 are both received between the upper portion 28A and the lower portion 28B of the blade support 28. In the case of a blade support 28 made of polymer material, the latter can for example be overmolded on the rear parts 26 of the scraper blade and of the stiffener, in order to ensure economical and reliable fixing.In all cases, through screws or rivets (not shown) may be provided to tighten the upper portion 28A and the lower portion 28B, ensuring or reinforcing the fixing, by pinching, of the scraper blade 22 and the stiffener 40 on the blade support 28. Such screws or rivets, or even dowels, may also be provided to pass through corresponding orifices arranged in the rear parts 26 of the scraper blade 22 and the stiffener 40, to securely lock the scraper blade 22 and the stiffener 40 on the blade support 28.

[0063] In the example of the Figure 9 , the gripping zone 32 is a manual gripping zone in the form of a handle which extends in the plane of symmetry defined by the scraping blade 22, and which extends along the median longitudinal axis A1 of the scraping blade 22 and of the stiffener 40.

[0064] On the Figure 10a fifth embodiment has been illustrated in which the tool body 30 has a blade support 28 identical or similar in design to those of the first, second and / or third embodiments described above, the assembly formed by the scraping blade 22 and the stiffener 40 being fixed to the blade support 28 in one of the ways described above. In this example, the gripping zone 32 is designed in the manner of the handle of a trowel, with a handle elongated in the longitudinal direction X, said handle however being offset vertically relative to the plane defined by the scraping blade 22. Advantageously, this handle may have, at the rear, a housing for connecting a tool handle, or pole, forming an interface zone with such a handle.

[0065] In the embodiments described above, it can be seen that the stiffener forms an excess thickness above the upper face 42 of the scraper blade 22. Depending on the methods of fixing the assembly formed by the scraper blade 22 and the stiffener 40 on the blade support 28, in particular if there is no, by the fixing method or by a geometry of the lower face of the blade support 28 against which the assembly comes to bear upwards, this excess thickness can cause a bulge of the scraper blade 22 and its front scraping edge 24. Thus, the lateral edges of the scraper blade 22, and therefore the lateral ends 25 of the front scraping edge 24, can be raised vertically upwards relative to the scraper blade 22 and its front edge 24 at the level of the median longitudinal axis A1, for example by a value of 1 to 3 millimeters.Such a bulge is not necessarily a disadvantage and tends on the contrary, in use, to accentuate the increase in pressure applied by the tool in the center relative to the lateral ends, which favors on the one hand the "tightening" of the joint strip 17, and on the other hand the lateral evacuation of the excess quantity of coating 18.

Claims

1. A tool (20) for clamping joint tape, comprising a scraping blade (22) which extends in a longitudinal direction (X) and a transverse direction (Y) perpendicular to each other, the scraping blade (22) having a front scraping edge (24) which extends in the transverse direction (Y) and which has a transverse working width greater than or equal to 180 millimeters, the scraping blade (22) being fixed, by a rear zone (26) of the scraping blade (22), to a blade support (28), according to a blade connection, characterized in that the blade connection extends over a transverse width representing at least 70% of the transverse working width, in thatthe joint strip clamping tool (20) comprises a stiffener (40) which: • is affixed against an upper face (42) of the scraper blade (22); • has a rear portion (44, 45) which is arranged between the scraper blade (22) and the blade support (52); • has a front edge (46) which is arranged in front of a front edge (29) of the blade support (28), defining, for the stiffener (40), a front overhang zone (48) which extends in front of the front edge (29) of the blade support (28) and which is free to deform relative to the blade support (28); • has a maximum width in the transverse direction which is in the range from 30 to 120 millimeters; and in that the front edge (46) of the stiffener is arranged to be set back longitudinally rearwardly relative to the front scraping edge (24) of the scraping blade (22) by a longitudinal setback value in the range of 0 to 30 millimeters.

2. A joint tape clamping tool according to claim 1, characterized in that the stiffener (40) is formed from a plate element separate from the scraper blade (22).

3. A joint tape clamping tool according to claim 2, characterized in that the scraper blade (22) is formed from a plate element having a thickness in the range of 0.2 to 2 millimeters, and in that the plate element of the stiffener (40) has a thickness of between 50% and 400% of the thickness of the plate element of the scraper blade (22), more preferably of between 100% and 250% of the thickness of the plate element of the scraper blade (22).

4. A joint tape clamping tool according to any preceding claim, characterized in that the stiffener (40) is arranged transversely in the center of the scraper blade (22), symmetrically with respect to a median longitudinal axis (A1) of the scraper blade (22).

5. A joint tape clamping tool according to any preceding claim, characterized in that the front edge (46) of the stiffener (40) has a convex profile.

6. A joint tape clamping tool according to any preceding claim, characterized in that the front edge (46) of the stiffener (40) is, at each of its transverse ends, connected to lateral edges of the stiffener (40) by rounded transverse ends (50).

7. A joint tape clamping tool according to any preceding claim, characterized in that the stiffener (40) is fixed to the scraper blade (22) in a fixing zone which is arranged, in the longitudinal direction, in the rear half of the length of the stiffener (40) in the longitudinal direction (X).

8. A joint tape clamping tool according to any preceding claim, characterized in thatthe scraper blade (22) and the stiffener (40) are made of metal.

9. A joint tape clamping tool according to any preceding claim, characterized in that the scraper blade (22) and the stiffener (40) are fixed to each other by welding or gluing.

10. A joint tape clamping tool according to any preceding claim, characterized in that the blade holder (28) comprises a front sole (36) having a lower face (52) and a rear heel (38), and in that the scraper blade (22) and the stiffener (40) are fixed on the lower face (52) of the front sole (36), in front of the rear heel (38).

11. A joint tape clamping tool according to any one of claims 1 to 9, characterized in that the blade holder (28) comprises a front sole (36) having a lower face (52) and a rear heel (38) having a lower face (58), and in thatthe scraper blade (52) and the stiffener (42) are fixed on the lower face (58) of the rear heel, and extend forward opposite the lower face (52) of the front sole (36).

12. A joint tape clamping tool according to any one of claims 1 to 9, characterized in that the blade holder (28) comprises a front sole (36) having a lower face (52) and a rear heel (36) having a housing (60) open towards the front, and in that the scraper blade (22) and the stiffener (40) are fixed to the blade support (28) by a rear area (26) of the scraper blade (22) which is engaged in the housing (60) of the rear heel (38).

13. A joint tape clamping tool according to any one of claims 10 to 12, characterized in that the front sole (36) has a front edge (29) which rests on an upper face of the stiffener (40).

14. A joint tape clamping tool according to any one of claims 1 to 11, characterized in that the scraper blade (22) and the stiffener (40) are fixed to the blade support (28) by double-sided adhesive pads (56) arranged on the upper face (42) of the scraper blade (22) transversely on either side of the stiffener (40), outside the perimeter of the stiffener (40).

15. A joint tape clamping tool according to claim 14, characterized in that the double-sided adhesive pads (56) have a thickness greater than the thickness of the stiffener (40).

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