FR2553332A1 - Method and instrument for planing, evening and smoothing out a surface, in particular a wall or floor surface - Google Patents

Abstract

The method according to the invention consists, before the layer to be planed has cured (set), in applying to the latter a float-disc 8a, in causing this float-disc to rotate at a rotational speed between 200 and 900 rpm, in moving the float-disc thus set into rotation over the entire surface in question and then in causing the float-disc to rotate at a higher rotational speed between 900 and 1500 rpm and moving it once again over the entire surface.

Description

PROCESS AND INSTRUMENT FOR LEVELING, STANDARDIZING
AND DRESS A SURFACE, ESPECIALLY SURFACE
MURAL OR SQL.

 The invention relates to a method for flattening, leveling and straightening a surface coated with a layer of hardening material; said process is implemented before hard breaking of said layer and can be applied to wall surfaces or floors, coated with mortar or other coating. The invention extends to an instrument allowing an operator to implement said method.

 We know that after placing a mortar coating on a surface, professionals smooth the surface by means of a trowel, consisting of a thin rectangular board; this float is applied to the surface by the operator and is moved parallel to this surface so as to sweep the whole thereof with appropriate movements to reach the desired surface state. This work is generally carried out in two successive phases (rough standardization and finishing) using two different floats. Such a process has several drawbacks. Firstly, this work using floats is delicate and long and requires skill only experienced professionals; it is extremely difficult for a beginner to reach a satisfactory surface finish. In addition, such work is physically very tiring, the operator having to perform multiple back and forth keeping the trowel in pressure against the surface. In addition, it requires changing the work tool between the initial phase and the finishing phase.

 The present invention proposes to overcome the aforementioned drawbacks by indicating an improved working process and by providing a new instrument for implementing it.

 One objective of the invention is in particular to allow a satisfactory surface condition to be achieved, by implementing quick, simple operations, within the reach of all, and much less tiring than those carried out using conventional floats.

 Another objective is to allow all of the work to be carried out with a single instrument.

 Another objective is to allow the obtaining of considerably improved surface conditions compared to the conventional method.

To this end, the process according to the invention, with a view to smoothing, standardizing and dressing a surface coated with a layer of hardening material such as mortar, plaster, coating, etc., consists, before hardening of said layer, to apply a disc, said disc-trowel, thereon having a face having smooth coplanar zones,
to cause this disc-float to rotate about an axis substantially perpendicular to said face at a speed of rotation substantially between 200 and 900 revolutions / minute, to move the disc-float thus rotated over the entire surface concerned, to then cause the disc-float to rotate at a higher speed substantially between 900 and 1500 rpm and to move the disc-float again over the entire surface.

 The instrument according to the invention, which is manipulated by the operator to carry out the above-mentioned smoothing work, essentially comprises a motor unit provided with an output shaft and adapted to supply at least two different rotational speeds, an operating button in order to authorize a selection of the speed of rotation of the engine block, a trowel disc mounts on the output shaft and having a face opposite to the block, called the front face, having smooth zones located in a plane substantially orthogonal to the output shaft, and a handle linked to the engine block at the rear of the float disc so as to allow the front face of the latter to be applied against the surface to be worked.

 It has been observed that the combination of the rotational movement and the sweeping of the surface makes it possible to achieve a perfect surface condition with a very limited number of passes, without the operator having to demonstrate experience or special skill; the working time is much shorter than in the conventional process, using floats, and requires reduced efforts, which, on an equal surface, results in a considerable reduction in the fatigue experienced. In addition, the same instrument is used throughout the work, with simply a change in the speed between the initial phase and the finishing phase.

 According to a preferred characteristic of the invention, the circular float disc comprises on S front face a plurality of cells which open on this face and are separated by smooth coplanar zones.

In the case of heterogeneous materials (in particular mortar made from sand), this arrangement ensures a better distribution of the various constituent bodies of the material and gives a finished, smooth and homogeneous surface.

 The engine block is advantageously of the type known per se, comprising an asynchronous electric motor and electrical supply means allowing at least two rotational speeds.

 The instrument according to the invention may include a handle articulated on the engine block so as to be able to pivot relative to the latter around an axis which is substantially parallel to the plane of the front face of the disc-float.

 In another embodiment, the sleeve is constituted by a handle attached to the engine block and extending the latter in a general direction substantially parallel to the plane of the front face of the disc-float or slightly inclined relative to this plane. (By "slightly inclined relative to this plane" is meant an inclination less than about 25).

Other characteristics of the invention will emerge from the description which follows with reference to the appended drawings, which present, by way of nonlimiting examples, two embodiments, on these drawings which form an integral part of this description:
FIG. 1 is a perspective view of a first embodiment in accordance with the invention,
- Figure 2 is a side view,
FIG. 3 is a plan view thereof, from the rear,
FIG. 4 is a detailed section through an axiai plane A,
FIG. 5 is a schematic view illustrating the use of this instrument,
- Finally Figure 6 is a side view of an alternative embodiment.

 The instrument shown by way of example in FIGS. 1, 2, 3 and 4 is intended to replace the mason's floats with a view to smoothing, leveling, leveling and smoothing a wall or floor surface, before drying the mortar covering that -this.

 This instrument comprises a motor unit 1 comprising in a casing a conventional asynchronous electric motor with a power of the order of 900 watts; this motor is associated with an electrical supply circuit, known per se, which makes it possible to supply it so as to rotate its output shaft 2 at two different speeds of rotation, a speed of the order of 600 revolutions / minute and a speed of the order of 1200 revs decreases. A speed selection button 3 is associated with said circuit to allow the operator to choose the desired speed.

 A handle 4 is articulated on the casing of the engine block l, so as to be able to pivot around an axis X orthogonal to the output shaft 2.

 In the example, the handle 4 is telescopic and is composed of a yoke 4a for its articulation, a first tube 4b secured to the yoke, a second tube 4c penetrating the first and handles 4d secured to the tube 4c.

A screw maneuvered by a knurled button 5 makes it possible to block the second tube 4c relative to the first and thus to adjust the length of the handle. The motor supply wire passes through the tubes 4b and 4c to enter, connected to the speed selection button 3, which is carried by one of the handles 4d.

 The handle 3 can be locked relative to the engine block l by a retractable pin 6 which can be housed in a slot 7 that includes one of the legs of the yoke 4a. In this position which allows convenient transport of the instrument, the handle has a general direction parallel to the output shaft 2.

 Furthermore, the output shaft 2 carries a float disc 8 of circular shape. This rigid plastic disc has a front face 8a (opposite the engine block l) which is provided with cells such as 9, separated by smooth coplanar parts.

 In addition, the circular edge 8b of the disquetaloche is curved towards the rear, that is to say towards the engine block. On its rear face, the trowel disc 8 is provided with radial ribs such as lO.

 The float disc 8, the diameter of which is around 45 cm, is removably fixed at its central part and at the end of the output shaft 2. In the example, this fixing is ensured by means of washers and a nut ll coming to be housed back with respect to the front face 8a, in a central housing 12 which the disc-float comprises; the nut ll is screwed onto the threaded end of the output shaft 2 which crosses the float disc. Of course, any other fixing means can be provided.

 When the disc-float is thus fixed, the plane of its front face 8a is orthogonal to the output shaft 2 so that this face 8a rotates in its own plane.

 Figure 5 illustrates the use of the above described instrument to smooth a wall surface coated with a fresh mortar coating. The operator applies the float disc 8 against the surface and selects the low speed of rotation. It scans the wall surface using the spinning disc. The finishing phase is carried out at the highest speed when the mortar has reached the appropriate consistency.

 It should be noted that the handle 4 which pivots about the axis X parallel to the plane of the front face 8a of the disc-float, makes it possible to apply the disc-float conveniently and effortlessly against the surface to be worked.

 FIG. 6 illustrates another embodiment in which the power of the motor is lower (400 watts) and in which the disc-float has a smaller diameter (0.25 cm). In this variant, the handle is constituted by a handle 13 secured to the engine block and carrying the speed selector. This handle extends the block radially, in a general direction substantially parallel to the plane of the front face of the float disc.

 This instrument is suitable for working on smaller areas or with numerous edges or other discontinuities. The instrument shown in Figure 6, which weighs approximately 3 kg, is well suited for working on walls, ceilings or floors; the instrument shown in figures 5, which weighs approximately 6 to 7 kg, is more particularly suitable for working the soil. In both cases, it should be noted that the engine block is balanced with respect to the axis of rotation.

 Of course, the invention is not limited to the terms of the above description, but includes all variants thereof.

Claims (13)

 l / - Process for leveling, leveling and leveling a surface coated with a layer of hardening material, such as mortar, plaster, characterized in that, before hardening of said layer, a disc, said disc, is applied to it float (8) having one face (8a) having smooth coplanar zones, this float disc is caused to rotate about an axis (2) which is substantially perpendicular to said face at a speed of rotation substantially between 200 and 900 rotations / minute, the disc-float is moved in this way over the entire surface concerned, the disc-float is then caused to rotate at a higher speed of rotation substantially between 900 and 1,500 revolutions / minute and it is moved to again the disc-float over the entire surface.  2 / - Method according to claim l, characterized in that one uses a float disc (8) having a face (8a) provided with a plurality of cells (9) separated by the coplanar smooth zones.  3 / - Method according to one of claims l or 2, characterized in that one uses a circular trowel which is caused to rotate around its center.  4 / - Instrument intended to be manipulated by an operator with a view to smoothing, standardizing and straightening, before hardening, a surface, characterized in that it comprises a motor unit (l) provided with an output shaft (2) and adapted to provide at least two different rotational speeds, an operating button (3) in order to authorize a selection of the rotational speed of the engine block, a disc-float (8), mounted on the output shaft (2) and having a face opposite the block, known as the front face (8a), having smooth zones situated in a plane substantially orthogonal to the output shaft, and a handle (4) linked to the engine block at the rear of the disc-float so as to apply the front face (8a) thereof against the surface to be worked.  5 / - Instrument according to claim 4, characterized in that the disc-float (8) is circular and comprises a plurality of cells (9) opening on its front face (8a) and separated by the aforementioned smooth areas.  6 / - Instrument according to claim 5, characterized in that the disc-float (8) has a circular edge (8b) curved backwards.  7 / - Instrument according to one of claims 5 or 6, characterized in that the disc-float (8) is made of rigid synthetic material and is provided on its rear face with radial ribs (10).  8 / - Instrument according to one of claims 4, 5, 6 or 7, characterized in that the float disc (8) is removably fixed at the end of the output shaft (2) by means of a nut (11) disposed back from the front face (8a), in a central housing (12) provided for this purpose.  9 / - Instrument according to one of claims 4, 5, 6, 7 or 8, wherein the motor unit (1) comprises an asynchronous electric motor and means of electric supply allowing two rotational speeds, one included between 200 and 900 rpm, the other between 900 and 1,500 rpm.  10 / - Instrument according to one of claims 4, 5, 6, 7, 8 or 9, characterized in that the handle (4) is articulated on the engine block (1) so as to be able to pivot relative to it- ci around an axis substantially parallel to the plane of the front face of the disc-float.  11 / - Instrument according to claim 10, characterized in that this tool comprises means (5, 7) for locking the handle, making it possible to block the latter relative to the engine block (1) in a direction substantially parallel to that of the output shaft (2).  12 / - Instrument according to one of claims 10 or 11, wherein the handle (4) is telescopic and comprises means for adjusting its length (4b, 4c, 5).  13 / - Instrument according to one of claims 4, 5, 6, 7, 8 or 9, wherein the handle is constituted by a handle (13) integral with the engine block and extending the latter in a general direction substantially parallel to the plane of the front face of the trowel disc or slightly inclined with respect to this plane.