Re-cutting machine for a mold for the production of building material test pieces

Description

FIELD OF APPLICATION OF THE INVENTION

[0001] The invention relates to the field of cement making and in particular to the field of tests carried out on mortar specimens for quality control purposes.

[0002] The invention relates more particularly to the leveling phase and in particular to the adaptations enabling this operation to be carried out in an optimized manner. BRIEF DESCRIPTION OF THE PRIOR ART

[0003] A process grouping together the different phases of these tests or tests of construction materials is described in particular by the NF EN 196-1 standard.

[0004] This standard describes the manufacture of mortar test specimens, i.e. in a mixture of cement, sand and water, and then the way in which the specimens must be tested. The specimens described take the form of a prism with a rectangular section.

[0005] When producing these specimens, the mortar is cast into a mold. This mold is an open mold typically comprising three specimen cavities. Due to the geometry of the mold, for each specimen, only one of the six faces is not defined by an internal surface of the mold.

[0006] In order to achieve a "good" casting and form this face of the test piece, the top of the mold is subjected to a leveling operation which removes the excess mortar and thus levels the mortar and the top edge of the mold before drying. This operation is supposed to guarantee the production of identical test pieces.

[0007] The applicant found that the repeatability of the results obtained during the test phases of the specimens could depend on this shaving operation. Thus, the applicant found that this shaving operation, which is part of the specimen manufacturing process, has an impact on the compressive strength of the samples.

[0008] However, this leveling operation is traditionally carried out manually. The absence of the operator or their replacement are therefore likely to influence the said results.

[0009] There are in the prior art a plurality of machines ensuring the automation of operations intended for the manufacture of products made of construction material such as those described in documents US1733706, CN107756600, JP2007245508 and US4432717 but these machines do not constitute a technical solution for the leveling of a mold of test piece(s) of construction material in particular in a standardized framework associated with laboratory tests.

[0010] Document CN 206 690 261 U discloses a machine for leveling the volume of excess material filling a test piece mold according to the preamble of claim 1. BRIEF DESCRIPTION OF THE INVENTION

[0011] Based on this situation, the applicant carried out research to improve the repeatability of this shaving operation in order to minimize the dispersion of the results obtained during the test phases of the specimens.

[0012] This research led to the design and production of an automated leveling machine for construction material test piece molds, providing a solution to the drawbacks observed.

[0013] This machine is designed for leveling test specimen molds of any shape and material. The mold can have one or more test specimen cavities.

[0014] The shaving machine of the invention is as defined in claim 1.

[0015] By automating the movements, such a machine makes it possible to reproduce the shaving parameters identically and to obtain the desired repeatability of the characteristics of the test pieces. It also makes it possible to define and control the strokes, speeds, and accelerations of said movement. These first back-and-forth movements are perpendicular to the longitudinal axis of the scraper.

[0016] This motorized mobility allows in particular to tilt the scraper differently depending on the direction of shaving. The definition of this orientation makes it possible to adapt to the material, the speed, etc. Thus, the angle of inclination of the scraper is variable and adjustable during the shaving of the same mold depending on whether the translation is in the forward or return direction.

[0017] The back and forth movements along the longitudinal axis of the scraper or shear are carried out at the same time as the back and forth movements carried out in the perpendicular direction. In addition, the amplitude of the shear is variable and adjustable during the leveling of the same mold.

[0018] According to another particularly advantageous characteristic of the invention, during the relative translational movement of the lower edge of the scraper on the upper edge of the mold, the table carrying the mold is movable and the scraper on this axis is fixed. Such a choice has the advantage of facilitating the dimensioning of the machine and makes it possible to limit its size.

[0019] According to another particularly advantageous characteristic of the invention, the scraper is guided in rotation by means of a movable gantry in translation perpendicular to the upper edge of the mold. This movement allows the scraper to move away from or towards the mold. It also facilitates the rotation of the scraper when changing the direction of leveling. Finally, it simplifies the installation and extraction of the mold.

[0020] According to a preferred but non-limiting embodiment, this translation is motorized.

[0021] According to another particularly advantageous characteristic of the invention, said mobile gantry comprises a pre-loading means, composed of springs, to maintain contact between said scraper and the upper edge of the mold.

[0022] According to a preferred embodiment, the value of the preload imposed by the scraper on the mold is adjustable. Adjusting the tension of said springs makes it possible to adjust the preload. This preload can thus be dynamically controlled and adjusted.

[0023] According to a preferred embodiment, said mobile gantry arranged above the table provides support, orientation, guidance and driving of the squeegee.

[0024] According to another particularly advantageous characteristic of the invention, said table supports an intermediate frame framing the mold and supporting at least one cleaning flap with which the scraper comes into contact to free itself from the material adhering to it.

[0025] According to a preferred but non-limiting embodiment, the machine comprises two cleaning flaps arranged on the intermediate frame on either side of the mold to correspond with the two ends of the stroke so that the scraper comes into contact with a flap at the end of each horizontal translational movement.

[0026] According to another particularly advantageous characteristic of the invention, under the cleaning flap, the intermediate frame is equipped with a groove for collecting the material detached by the flap. The machine can thus be cleaned by extracting the intermediate frame and cleaning the latter.

[0027] The mobile gantry includes a means for guiding and driving the scraper for its back-and-forth movements in translation along its longitudinal axis.

[0028] According to a preferred but non-limiting embodiment, this longitudinal translation of the squeegee is motorized.

[0029] According to a preferred embodiment, all of the movements are motorized.

[0030] According to the invention, the various movements are motorized by means of stepper motors.

[0031] This motorization technology allows for precise and controlled movements. The control module also allows these settings to be recorded and offers several trimming programs.

[0032] By motorizing all the movements necessary for shaving, the machine of the invention therefore makes it possible to optimize the repeatability of a plurality of different shavings resulting from different settings recorded in different programs made available to the user by the control module.

[0033] The machine combining the different characteristics described above is a four-axis machine (three translations, one rotation), whose different movements are dynamic (they can evolve during the operation) and controlled (in position, speed and acceleration), where it is possible to dynamically adjust the pressure applied by the rule on the mold and where the rule is cleaned.

[0034] The fundamental concepts of the invention having just been set out above in their most elementary form, other details and characteristics will emerge more clearly on reading the description which follows and with reference to the appended drawings, giving by way of non-limiting example, an embodiment of a leveling machine in accordance with the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] There figure 1 is a schematic drawing of an exterior perspective view of an embodiment of a leveling machine according to the invention; The figure 2 is a schematic drawing of an exterior front view of the machine of the figure 1 ; There figure 3 is a schematic drawing of a sectional side view of the machine of the figure 1 according to the section plane AA defined on the drawing of the figure 2 ; There figure 4 is a schematic drawing of a sectional side detail view of the machine of the figure 1 with the scraper in the straight position in contact with the upper edge of the mold; The figure 5 is a schematic drawing of a detailed perspective view of the mobile gantry supporting, guiding and driving the scraper; The figure 6 is a schematic drawing of a front detail view of the mobile gantry of the figure 5 ; There figure 7 is a schematic drawing of a detailed side view of the squeegee adopting a certain inclination; The figure 8 is a schematic drawing of a detailed side view of the squeegee adopting an inclination opposite to that of the figure 7 . DESCRIPTION OF AN EMBODIMENT

[0036] As illustrated in the drawing of the figure 1 , the shaving machine referenced M as a whole, comprises a frame 100 accommodating on the front face a work station where a table 200 is movable horizontally along the X axis.

[0037] This table 200 accommodates a mold 210 composed of three test specimen cavities 211, 212, 213. These cavities 211, 212, 213 are open and have the same upper edge 214. They are full during operation of the machine M. The filling of the mold 210 is carried out during a preliminary operation not illustrated. Once filled, the mold 210 is positioned on the table 200. As illustrated, the table 200 accommodates an intermediate frame 201 framing the mold 210.

[0038] A 300 control module manages the shaving programs. It controls the various actuators of the M machine according to the program selected by the user.

[0039] As illustrated, the opening or closing of a tailgate 110 hinged relative to the front face of the frame 100 makes it possible to close or open the workstation where the leveling takes place and where the table 200 moves in order to: to close access during leveling for protection purposes; to provide access during related operations (positioning, mold removal, maintenance, etc.).

[0040] According to a particularly advantageous feature not illustrated, the workstation includes an internal lighting means facilitating operations and vision in the workstation.

[0041] As illustrated in the drawing of the figure 2 , a 400 scraper or leveling ruler moves above the table and is associated with a 500 mobile gantry.

[0042] According to a preferred but non-limiting embodiment, the upper surface of the intermediate frame 201 is located a few millimeters below the upper edge 214 of the mold 210 so that the scraper 400 is always in contact with the mold 210. This clearance can be adjusted by adjustment screws.

[0043] The mobile gantry 500 guides and drives the squeegee 400 according to: a vertical translation movement along the Z axis to move it away from or towards the table 200 and therefore the mold 210; a horizontal translation movement along the Y axis for shearing the material, here mortar; a rotation movement along the Y axis to modify the leveling angle.

[0044] These movements associated with the horizontal translational movements of the table 200 and therefore of the mold 210 along the X axis make it possible to reproduce the movements of a leveling operation.

[0045] As illustrated in the drawing of the figure 3 , said table 200 is connected in the lower part by a helical connection to a trapezoidal threaded rod 220 driven in rotation by means of a stepper motor 230. This drive ensures the back and forth movements in horizontal translation along the X axis.

[0046] As illustrated in this figure 3 and on the figure 4 , said intermediate frame 201 is further equipped with two cleaning flaps 241 and 242 comprising a flexible part projecting upwards and with which the scraper 400 is in contact during the end of translational travel of the table 200. To do this, these flaps 241 and 242 are arranged on the intermediate frame 201 at the ends of the table 200 on either side of the position of the mold 210.

[0047] The translational movements of the table 200 (and therefore of the intermediate frame 201 arranged thereon) along the X axis are defined so that the scraper 400 extends beyond the end of the mold 210 and comes into contact with said flaps 241 and 242. The excess material scraped by the scraper 400 and adhering to the latter then detaches and falls. This material is collected in channels 243 and 244 arranged under the flaps 241 and 242 and formed in the frame 201.

[0048] The flaps 241 and 242 have a certain inclination relative to the squeegee 400. When it is in contact with the flap, the automation of the movements allows the squeegee 400 to also follow an upward movement at the end of its stroke in order to facilitate the detachment of the material adhering to it after each pass.

[0049] As illustrated on the figures 2 , 3 And 5 , the mobile gantry 500 providing support, guidance and driving of the scraper 400 above the mobile table 200 and therefore the mold 210, is mobile in vertical translation along the Z axis. It is arranged above the table 200 and is composed of two mobile assemblies 510 and 520 connected by a transverse beam 530.

[0050] The vertical mobility of the gantry 500 is implemented by a helical connection with two vertical threaded rods. According to the illustrated embodiment, each mobile assembly 510 and 520 is equipped with a threaded sleeve 511 and 521 cooperating with a vertical trapezoidal threaded rod 512 and 522, the two rods 512 and 522 being mechanically synchronized.

[0051] These mobile assemblies 510 and 520 comprise a frame 513 and 523 inside which a mobile or floating part moves along a vertical axis 514 and 524 supporting the subassemblies angularly orienting the scraper 400 and guiding and driving the latter in translation along the Y axis.

[0052] Said threaded sleeves 511 and 521 are associated with the frame 513 and 523 of each mobile column 510 and 520.

[0053] The mobility of the moving parts 514 and 524 is accompanied by springs 515 and 525 which hold the moving parts in the low position. Thus, when the rotational movement of the threaded rods 512 and 522 brings the scraper 400 into contact with the upper edge of the mold 210 as illustrated in the drawing of the figure 4 , the moving parts 514 and 524 rise and are subjected to the stress of the springs which tend to bring them back down.

[0054] The scraper 400 is thus pre-loaded on the upper edge 514 of the mold 210 which guarantees contact and therefore leveling during the movement of the table 200.

[0055] The angular orientation of the squeegee 400 is illustrated by comparing the drawings of the figures 4 , 7 And 8 . As illustrated on the figures 7 And 8, this orientation changes depending on the direction of shaving. It is implemented by a rotational drive of the scraper 400 which must not only be oriented angularly but must also ensure a shearing movement, i.e. back and forth along the Y axis during the shaving phase. To do this, a sliding pivot connection is implemented between the moving parts 514 and 524 and the scraper 400 to allow the adjustment of the angular orientation and the back and forth translational movement.

[0056] A motor sets in motion a pinion 411 which sets in motion a toothed wheel 412 whose center forms a sliding sleeve 413 for a first portion of horizontal shaft with prismatic section 414 connected to one end 401 of the scraper 400. The other end 402 of the scraper 400 is connected to a second portion of horizontal shaft 415 which is cylindrical but coaxial with the first and slides in a bearing 416 housed in the movable part 514. The rotation of the toothed wheel 412 orients the scraper without preventing its longitudinal sliding.

[0057] As illustrated, the axis of rotation of the scraper defined by the position of the shaft portions 414 and 415 is positioned at the lower edge of the scraper 400. This positioning minimizes the torque required to maintain the orientation of the scraper 400 during shaving.

[0058] The translational drive for the back-and-forth movements of the scraper along its longitudinal axis is implemented by a drive fork 420 whose lower end is connected by a pivot connection to the shaft portion 415 and whose upper end is fixed to a moving part 421 provided with a hollow core tapped so as to cooperate with a horizontal trapezoidal rod 422 whose rotation in one direction then in the other ensures a back-and-forth movement of the moving part 421. The back-and-forth movement of the moving part 421 is transmitted by means of the fork 420 to the scraper 400 which can thus carry out the shearing movements intended for leveling. A stepping motor 423 drives said trapezoidal rod 422 in rotation.

[0059] The guidance of this translational movement of the moving part 421 is implemented by a pair of horizontal smooth rods 531 and 532 connecting the two moving parts 514 and 524 of the moving assemblies 510 and 520. The rotational guidance of the horizontal trapezoidal rod 422 is implemented by two bearings 424 and 425 fixed to said rods between which the moving part 421 moves.

[0060] An example of the operating method of the shaving machine is described below.

[0061] Once filled with mortar, the mold 210 is placed on the table 200. The scraper 400 is then in the high position. The operator closes the tailgate 110 and launches one of the proposed leveling programs from the control module 300. The control module 300 then controls the various movements.

[0062] The scraper 400 is angularly oriented by the motor 410. The movement of the threaded rods 512 and 522 moves the movable gantry 500 downwards and brings the oriented scraper 400 into contact with the upper edge 214 of the mold 210. The movable parts are then slightly raised and constrained by the springs 515 and 525 so that the scraper 400 remains in contact with the upper edge 214 of the mold 210.

[0063] The table 200 is then set in motion in horizontal translation along the X axis by the motor 230. Simultaneously, the motor 423 ensures the horizontal back-and-forth movement of the scraper 400.

[0064] Once the table 200 has reached the end of its travel, the scraper 400 comes into contact with a flap to free itself from the mortar that has remained stuck. The table 400 is stopped in translation. The vertical threaded rods 512 and 522 are then actuated to raise the mobile gantry 500. This movement finalizes the cleaning of the scraper 400 and allows the motor 410 to change its orientation. Once its orientation is reversed, the vertical threaded rods 512 and 522 are actuated so as to put the scraper 400 back into contact with the upper edge 214 or the table 200. The latter is then driven in translation in the opposite direction.

[0065] This cycle can be repeated until a satisfactory level is achieved.

[0066] This machine motorizes and automates all the movements related to shaving. It makes all the parameters of this shaving (stroke, speed, acceleration, inclination, etc.) adjustable using stepper motors.

[0067] In accordance with the invention, it thus optimizes the repeatability of the actions carried out during the leveling operation.

[0068] It is understood that the machine which has just been described and represented above has been done so with a view to disclosure rather than limitation. Of course, adjustments may be made to the machine without departing from the scope of the invention as defined by the attached claims.

Claims

1. Machine (M) for shaving the volume of excess material filling a test piece mould (210), the machine (M) comprising - said mould (210) comprising an upper edge (214), - a squeegee (400) the lower edge of which comes into contact with the upper edge (214) of the mould (210) for shaving purposes, - a table (200) accommodating the test piece mould (210) containing said material, and - a control module (300) controlling the motorization of the relative translational movement of either the table (200) with respect to the squeegee (400) or the squeegee (400) with respect to the table (200), in order to carry out a plurality of translational back-and-forth movements of the lower edge of the squeegee (400) over the upper edge (214) of the mould (210), the squeegee (400) being mobile according to a movement: - rotating about an axis parallel to its longitudinal axis in order to orient its angular position relative to the rim (214) of the mould (210) and fix it, and - in translation along an axis parallel to its longitudinal axis in order to impart to it, once in contact with the upper rim (214) of the mould (210), a shearing movement consisting of back-and-forth movements along its longitudinal axis, characterised in that the different movements are motorised by means of stepping motors.

2. Machine (M) according to claim 1, characterised in that the machine is configured such that during the relative translational movement of the lower edge of the squeegee (400) over the upper edge (214) of the mould (210), the table (200) carrying the mould (210) is mobile and the squeegee (400) is fixed.

3. Machine (M) according to claim 1, characterised in that the squeegee (400) is guided in rotation by means of a gantry (500) movable in translation perpendicularly to the upper edge of the mould allowing the squeegee (400) to move away from or closer to the mould (210).

4. Machine (M) according to claim 3, characterised in that said movable gantry (500) comprises a preloading means, composed of springs (515, 525), for maintaining the contact between said squeegee (400) and the upper edge (514) of the mould (210).

5. Machine (M) according to claim 3, characterised in that said movable gantry (500) comprises a means for guiding and driving the squeegee (400) for its translational back-and-forth movements along its longitudinal axis.

6. Machine (M) according to any one of claims 1 to 4, characterised in that said table (200) supports an intermediate frame (201) framing the mould and supporting at least one cleaning flap (241, 242) with which the squeegee (400) comes into contact to release the material adhering thereto.

7. Machine (M) according to claim 6, characterised in that under the cleaning flap (241, 242), the intermediate frame (201) is equipped with a recovery gutter (243, 244) for recovering the material detached by the flap (241, 242).