WO1997046775A1

WO1997046775A1 - Vibration generator with portable needle.

Info

Publication number: WO1997046775A1
Application number: PCT/FR1997/000994
Authority: WO
Inventors: Daniel Forest
Original assignee: Daniel Forest
Priority date: 1996-06-05
Filing date: 1997-06-05
Publication date: 1997-12-11
Also published as: EP0901550B1; ES2154046T3; FR2749602A1; DE69703544T2; FR2749602B1; DE69703544D1; EP0901550A1

Abstract

The invention features a vibration producing apparatus comprising in combination: a tube (6) closed at one of its ends (12); an offcenter body (9); two bearings (10, 11) located inside the tube (6); an axial compression resistant but flexible tubular sleeve (15), extending the tube (6) and of the same external diameter; a flexible sheath (21) contained in the sleeve (15) and formed by two helical strands coiled in opposite directions, a flexible transmission shaft (22); means (26, 27) connecting the tube (6) and the sleeve (15); a rigid fixing head (19), equipped with joining means (40) for coupling the shaft (22) with a connection pin (4) of a driving electric motor (1) associated to the apparatus handling means (2, 3).

Description

PORTABLE NEEDLE VIBRATOR

The invention relates to a portable needle vibrator, that is to say an apparatus for producing vibrations with a view to compacting materials, in particular concrete, of the so-called internal vibrator or vibrating needle type, comprising a formed needle. of a tube, adapted to be immersed inside a mass of materials to be compacted and to emit therein mechanical vibrations propagating in directions at least substantially radial with respect to the longitudinal axis of the needle.

Needle vibrators have been known for a long time and are used on construction sites by professionals to vibrate concrete. These devices include a vibrating needle incorporating a pneumatic (turbine) or electric motor connected to an air compressor or to a source of electric energy by an air or electricity supply cable. As a variant, the electric motor is separated from the needle, is placed on the ground and connected by a long flexible transmission to the needle which is then of the pendulum type. The motor must drive the needle at speeds above 10,000 rpm. These devices have many practical drawbacks: they are heavy, bulky, difficult to handle, noisy. In addition, they are expensive and can only be used with an air compressor, or a three-phase electric current source and / or an electric converter, which generally puts them beyond the reach of the handyman and the craftsman. .

We have already thought of making a needle vibrator driven by an electric motor which can be the motor of an electric drill. US-2, 232, 842 thus describes a vibrator comprising a tube carrying an eccentric body by means of two bearings fixed on supports at each end of the tube, a flexible shaft connecting the eccentric body to the shaft outlet of an electric motor, a sheath surrounding the flexible shaft, a plurality of superimposed concentric metal braids, and a layer of vulcanized rubber extending between connecting parts to the motor housing and to the tube. The assembly is extremely complex, requires a large number of parts, and is expensive to manufacture and assemble.

DE-U-29 515 762 describes a vibrator adaptable to the mandrel of an electric drill comprising a tube containing an eccentric body, a flexible shaft connected to the eccentric body and to the mandrel of the drill, a flexible rubber hose extending between a fitting to the tube and a fitting at the end of the shaft inserted into the mandrel. Each fitting includes a shaft guide bearing. This device is free of sheath protecting the shaft, which allows relative movements of the shaft inside the <- hose, leading to wear of the rubber hose, and to phenomena of vibration, and flapping. Furthermore, the drill chuck is not protected from water or concrete protections, which also leads to rapid wear of the drill (in particular of its bearing). The assembly requires numerous machining operations, a large number of parts, and is expensive to manufacture and complex to assemble. The principle of compacting concrete by internal vibrations using vibrating needles has been known for a very long time (more than 50 years). We also know the importance of vibrating concrete to improve its quality and performance. Thus, the use of non-vibrated concrete is not allowed in public works. The need has therefore been felt more and more for just as long to allow the use of such vibrators by craftsmen or DIY enthusiasts. However, in view of the aforementioned drawbacks of the devices described in US-2,232,842 and DE-U-29,515,762, no practical solution has so far been proposed, which makes it possible to simultaneously satisfy all the criteria to be met for this make, to know :

- price criterion: device that can be offered at an acceptable price for a craftsman or a handyman who only makes occasional use of it, in particular at a price of the same order as that of a portable drill or other electronic DIY tool ,

- ergonomic criteria: portable device of low weight, small footprint, easy to install and use, safe and comfortable, - performance criterion: service life and robustness compatible with particularly harsh environments where vibrators must be used, ability to serve in the most diverse situations encountered on small-scale construction sites, possibility of passing through and behind obstacles or reinforcement, high vibration efficiency compared to engine power, homogeneity of vibrations over the entire height useful of the needle, possibility of fully introducing the needle into the concrete without any rise in concrete during extraction.

The invention therefore aims to provide a device of the needle type for the production of vibrations for the compaction of materials, in particular concrete, which provides a solution to this problem and can in practice satisfy the market of craftsmen or DIY enthusiasts.

To do this, the invention relates to a needle-type device for producing vibrations for the compaction of a mass of materials, in particular concrete, comprising in combination: a) a tube closed at one of its ends, b) an eccentric body of elongated shape, rotatably mounted in the tube, c) two bearings housed inside the tube, one in the vicinity of its closed end the other in the vicinity of its other end, so guiding the eccentric body in rotation, d) a tubular sleeve extending the tube, of external diameter substantially identical to that of said tube, this sleeve having a resistance in axial compression and a shape adapted to allow the introduction of the tube within said mass of materials, but an appropriate flexibility to allow its bending in the case where resistance is encountered during the introduction (in particular to allow its deformation in bending and the circumvention of obstacles encountered by the tube during its insertion into the mass of materials), e) a flexible sheath contained in the sleeve, and comprising at least two helical strands wound in opposite directions, coaxial, one inside the other, surrounded by an outer tubular covering, f) a flexible transmission shaft contained in the flexible sheath and coupled to the body eccentric (9) in order to be able to drive it in rotation, g) means for connecting the tube and the sleeve, adapted, on the one hand, to secure the ends d e these tube and sleeve ensuring at least substantially a continuity of their external surfaces, on the other hand, to achieve the maintenance of the end of the sheath relative to said tube and sleeve, h) a rigid head for fixing the other end of the sleeve and of the sheath, equipped with junction means making it possible to couple the shaft to an output pin of an electric motor for rotating drive associated with means for handling the device by a user. Throughout the text, by crimping, any process of coupling in rotation and of axial connection of a female part and a male part is designated by relative plastic and / or elastic deformation of at least one of the two parts. This term therefore includes not only the actual crimping with or without bonding, but also hooping assemblies (elastic deformations).

The tubular sleeve attached around the tree and its sheath have several functions and advantages combined:

- it ensures diameter continuity from the needle to the motor, - it acts as means of association and relative holding of the needle in an axial position relative to the motor,

- it nevertheless allows relative movements in bending of the needle relative to the axis of the motor, if necessary,

- it dampens and attenuates the transmission of vibrations from the needle to the handling means,

- It is low cost, and easy to change, in the event of wear or to adapt the characteristics (dimensions, resistances, elasticity.) according to the needle and the uses, in particular according to the viscosity of the mass of materials to be vibrated. .

Advantageously and according to the invention, the mechanical characteristics of the tubular sleeve and of the sheath formed by the two helical strands are adapted according to the use intended for the device, so that the needle (closed tube and eccentric rotary body of elongated shape) can be introduced into the mass of material by the own weight of the needle possibly supplemented by a slight vertical thrust from top to bottom exerted by a user manually on the handling means, while allowing relative movements in bending in the case where a greater resistance is encountered during the introduction, and by ensuring an elasticity in bending bringing back and keeping the needle at rest in the axial extension of the sleeve and the output pin.

Advantageously and according to the invention, the sleeve is made of synthetic material possibly composite and / or reinforced and / or with non-stick external surface.

According to the invention, the tube and the sleeve have the same external diameter, and this diameter is advantageously between 20 mm and 50 mm, more particularly between 25 mm and 35 mm. In practice, the diameter of the tube is determined as a function of the radial dimensions of the eccentric body forming an unbalance, and of the bearings which support it.

In addition, the length of the tube is determined so that the device can be used in the majority of situations encountered. Advantageously, this length is between 200 mm and 400 mm, more particularly between 250 mm and 350 mm. According to the invention, the length of the tubular sleeve is adapted to allow working at height, the user having the device in hand, carrying it and holding it by the handling means associated with the drive motor. Advantageously and according to the invention, the length of the sleeve is between 1 and 10 times the length of the tube. Advantageously and according to the invention, the length of the sleeve is between 250 mm and 2000 mm, in particular of the order of 500 mm. Advantageously and according to the invention, said means for connecting the tube and the sleeve are means for fitting and crimping a male end piece into a female end piece. Advantageously and according to the invention, said connection means comprise a connection piece interposed between the sleeve and the tube.

Advantageously and according to the invention, the connection means define a cylindrical groove for receiving and crimping the end of the sleeve and the end of the flexible sheath, and this cylindrical groove comprises ribs projecting towards the inside from an external wall of the cylindrical groove to enter the sleeve.

Advantageously and according to the invention, said joining means comprise: - a coupling part mounted integral in rotation by crimping at the end of the shaft,

- an adapter piece arranged so as to connect and couple the coupling piece to the spindle output, this adapter being coupled in rotation to the output pin by screwing, the coupling piece defining a housing for receiving the adapter, this receiver and the adapter having shapes conjugates adapted to prevent any relative rotation and to ensure the coupling in rotation of the adapter part with respect to the coupling part.

In another variant, advantageously and according to the invention, said joining means comprise:

- a coupling part mounted integral in rotation by crimping at the end of the shaft, and coupled to the output pin by removable means of coupling in rotation, - at least one access lumen formed through the head rigid opposite the output pin for mounting and coupling the coupling piece on the output pin.

The removable coupling means can be produced in the form of a screw / nut system accessible by the access port, or a coupling with axial splines and / or radial plug.

Advantageously and according to the invention, the rigid head comprises a cartel, and a part for fixing the end of the sleeve and of the sheath relative to the casing. Advantageously and according to the invention, the fixing piece is rigidly associated with the casing of the rigid head, and defines a cylindrical housing for receiving and crimping the end of the sleeve and the end of the flexible sheath, this cylindrical housing. comprising ribs projecting inwardly from an outer wall of the cylindrical housing to penetrate the thickness of the sleeve.

Advantageously and according to the invention, the tube is closed by a rounded plug, fixedly installed at the end of the tube. The tube is also rigid, preferably made of metallic material.

Advantageously and according to the invention, the eccentric body is coupled to the end of the shaft by crimping.

Advantageously and according to the invention, each bearing is a bearing, the eccentric body comprises two pins carried by the inner cages of the two bearings, and one of the pins is directly coupled to the end of the shaft - in particular by crimping -.

Advantageously and according to the invention, the inner cages of the bearings are fixed to the journals, and the outer cages of the bearings are inserted into the tube with a radial clearance.

Advantageously and according to the invention, the eccentric body comprises a cylindrical central core guided by the bearings, and a portion of cylinder - in particular a half-cylinder - attached attached to the core to form an imbalance around the axis of rotation of the soul defined by the bearings. Such an eccentric body is extremely simple and inexpensive to manufacture.

Advantageously and according to the invention, the flexible sheath comes into contact with the cylindrical internal wall of the sleeve and the shaft is mounted in the flexible sheath with a radial clearance.

Advantageously and according to the invention, the electric motor is adapted to drive the output pin and the eccentric body at a rotational speed of less than 5000 rpm, in particular between 2500 and 3500 rpm.

Furthermore, the device can be the subject of several embodiments. In a first embodiment, it is coupled to a traditional portable drill with an electric motor. To do this, advantageously and according to the invention, said joining means are of the removable type, preferably with rapid assembly and disassembly. In addition, in this embodiment, the drill comprises, in a traditional manner, handling means which act as means for handling the apparatus according to the invention.

In a second embodiment, the device is completely autonomous and incorporates an electric drive motor. Thus, the device is characterized in that it comprises: i) an electric drive motor comprising an output pin coupled to the end of the flexible shaft by a coupling part, in particular crimping at the end of the tree. This electric drive motor is housed in a casing which carries or which defines the means of handling the device (handle, motor control button, etc.).

In all the embodiments, advantageously and according to the invention, the rigid head comprises a casing, and a part for fixing the end of the sleeve and of the flexible sheath relative to the casing. The invention also relates to an apparatus comprising in combination all or part of the characteristics mentioned above or below.

It should be noted that the combination of the characteristics of the invention, and in particular the use of a sheath formed by two helical strands wound in opposite directions, makes it possible to protect the flexible shaft whatever its direction of rotation and what with a very small radial size (therefore a small total diameter of the vibrating needle), in an extremely simple and inexpensive manner, so that the vibrator is at the same time robust, efficient, lightweight, and very inexpensive. Such a sheath limits the torsional clearances of the flexible transmission in the two directions of rotation, makes it possible to dampen the transmission of vibrations, and ensures appropriate flexibility and elasticity in bending and a long service life for the transmission.

Thus, the combination of characteristics of the invention makes it possible to end up with a very light portable device, allowing work at height, whose needle and tubular sleeve (incorporating the flexible shaft and sheath) are of small diameter, highly vibratory, able to be easily inserted through or behind reinforcements or obstacles or into recesses, and low cost. In addition, the use of an elongated eccentric rotary body mounted between two bearings as a source of vibration allows the coupling of the vibrating needle to a drive motor associated with means for handling the device, and this by means of a transmission (shaft, sheath with two helical strands and flexible tubular sleeve), whose flexibility and bending elasticity are a compromise allowing both the passage around obstacles and the introduction of the needle, while preventing the needle and / or the flexible transmission from being subject to parasitic movements (beating, swaying, etc.). In addition, this embodiment of the needle allows, thanks to its small diameter (especially between 20 and 50 mm), to use a tubular sleeve of the same diameter and appropriate flexibility. The vibrations produced are of homogeneous amplitude over the entire height of the needle, of high efficiency (no energy losses in non-radial directions), and are not retransmitted to the means of handling the device. The user can therefore carry, handle and guide the needle while holding the device by the motor housing, in a simple and comfortable manner. Also, when the needle is extracted, there is no raising of concrete and the space left by the needle outlet, of small diameter, fills up as the extraction takes place.

Other characteristics, objects and advantages of the invention will appear on reading the following description of its preferred embodiments which refer to the appended figures in which:

- Figure 1 is a schematic perspective view of an apparatus according to a first embodiment of the invention, shown in the operating position whose tubular sleeve is bent by the presence of an obstacle that a frame in the material to vibrate,

- Figure 2 is a schematic view in perspective of an apparatus according to a second embodiment of the invention, shown in the operating position with the tubular sleeve not bent,

FIGS. 3a and 3b are schematic views in axial section, representing the rigid head, and the joining means according to, respectively, two alternative embodiments of the joining means of an apparatus according to the invention,

FIG. 4 is a schematic exploded perspective view, partially broken away, of the joining means according to the variant embodiment of FIG. 3a,

FIGS. 5a and 5b are schematic views in axial section showing the connection means and the tube according to, respectively, two alternative embodiments of the connection means of an apparatus according to the invention,

- Figures 6 and 7 are schematic cross-sectional views along lines VI-VI and, respectively, VII-VII of Figure 3a, - Figures 8, 9 and 10 are schematic cross-sectional views along lines VIII -VIII, IX-IX and XX, respectively, of FIG. 5a,

- Figure 11 is a schematic front view in axial section showing the rigid head and the joining means of an apparatus according to the second embodiment of the invention.

The device shown in FIG. 1 is of the type intended to be fixed on a traditional portable electric drill, which therefore does not form an integral part of the device according to the invention in this embodiment. The drill 1 comprises, in a traditional way, a handle 2 for maneuvering, a button 3 for controlling an alternating electric motor (single-phase 220 V rotating at a speed conventionally between 1500 rpm and 4000 rpm) drive in rotation of an output pin 4. The drill chuck is removed for mounting the device according to the invention. The apparatus according to the invention comprises a vibrating needle 5 formed of a tube 6 closed at one 7 of its ends by a rounded metal plug 8 mounted irremovable, for example retracted by force and / or glued and / or punched at the end of the tube 6. The vibrating needle 5 also comprises an eccentric body 9, of elongated shape, rotatably mounted in the tube 6, by means of two bearings 10, 11 each formed by a bearing, and housed inside of the tube 6, one in the vicinity of its closed end 7, the other in the vicinity of its other end 12, so as to guide the eccentric body 9 in rotation.

The needle 5 thus formed is associated with an engine block (drill 1) by means of a flexible tubular assembly 14. This tubular assembly 14 essentially has two functions: firstly, it allows the mounting of the needle 5 relative to the engine block 1, so that the needle 5 is carried by this engine block 1. Thus, when we manipulate the means 2, 3 for handling the drill 1, we carry and guide the needle 5. The tubular assembly 14 also has the function of transmitting the rotary movement of the output pin 4 to the body 9 offset for the '' rotate.

The tubular assembly 14 comprises a tubular sleeve 15 extending the tube 6, of external diameter at least substantially identical to that of the tube 6. Thus, the outer surface 16 of the tubular sleeve 15 extends at least substantially in continuity and in extension of the outer surface 17 of the tube 6. The tubular sleeve 15 is hollow cylindrical and defines in sealed manner with the engine block 1 and the tube 6, a closed cylindrical internal space.

The sleeve 15 is dimensioned and made of a material appropriately chosen so that it has an axial compressive strength and a shape adapted to allow the introduction of the tube 6 within the mass of the material to be compacted, but sufficient flexibility sufficient to allow its bending in the event that a resistance, greater than the resistance opposed by the sole material, is encountered during the introduction, in particular in the event of a stop against a reinforcement or an obstacle, as shown in FIG. 1. The sleeve 15 has a shape at rest which is straight, that is that is to say straight. It is connected to the tube 6 by one 18 of its ends, and connected to a rigid head 19 by its other end 20, so that the outlet pin 4, the sleeve 15, and the tube 6 are aligned on the same axis when the device is at rest. Advantageously, the tubular assembly 14 is dimensioned and made of a material chosen so that when the device is held by the user, this tubular assembly 14 can be maintained with a straight shape when the needle 5 is normally introduced. inside the mass of material without encountering any obstacle, as shown in Figure 2.

According to the invention, the sleeve 15 consists of an axially incompressible but flexible hollow tube of synthetic material. This synthetic material can be composite or not, reinforced or not, plastic or elastic. The mechanical characteristics of this material and of the hollow tube are chosen to obtain a resistance in axial compression and a flexibility of the tubular assembly 14 as mentioned above. In addition, the outer surface 16 of the sleeve

15 is advantageously covered or made of a non-stick material such as TEFLON (registered trademark) in order to avoid sticking to the mass of material on extraction. The tubular assembly 14 comprises a flexible transmission incorporated inside the tubular sleeve 15. This transmission comprises a flexible sheath 21 contained in the sleeve 15, and a flexible transmission shaft 22 contained in the flexible sheath 21 and coupled to the body 9 offset to be able to drive it in rotation. The mechanical and dimensional characteristics of the flexible transmission are adapted to allow transmission of the torque of the drive motor of the engine block (drill 1) to the eccentric body 9, allowing bending deformations of the tubular assembly 14.

The flexible shaft 22 is for example a flexible metal shaft whose length is of the order of, or slightly greater than that of the sheath 21, so as to have two ends 23, 24, one of which 23 is coupled to the output pin 4 of the drive motor, and the other 24 of which is coupled to the eccentric body 9. The flexible shaft 22 is for example formed of at least one metallic filament wound in helical turns, contiguous or not, or even of two coaxial and concentric filaments wound in opposite directions, extending one inside the other. and joined at their ends. It is possible, for example, to use a flexible TECHNOFLEX shaft sold by the company HERLEM et Cie (France).

The sheath 21 is adapted to allow free rotation of the shaft 22 about its axis. In the embodiments shown, a radial clearance 25 is formed between the shaft 22 and the sheath 21.

The flexible sheath 21 is a metal sheath comprising at least two helical strands 70, 71 wound in opposite directions (that is to say of opposite steps, one on the left, the other on the right), extending one (70) inside the other (7). In addition, the flexible sheath 21 advantageously comprises an outer tubular covering 72 surrounding the outer helical strand 71. This covering 72 is for example in the form of a metal braid and / or a synthetic film matching the outer helical strand 71 Such a sheath 21 makes it possible to limit the games in torsion in both directions, is flexible, and elastic in bending.

Each helical strand 70, 71 is a strand formed from a winding of an elastic metallic filament, for example of hard steel, in disjoint regular turns. Preferably, the cross section of the filament forming the strands 70, 71 is flattened. She is in shape substantially oval or rectangular. The two strands 70, 71 can be formed from the same metallic filament or not. Preferably, the turns of the inner helical strand 70 come into contact with the turns of the outer helical strand 71 which are themselves coated with the outer covering 72.

Advantageously, a radial space 25 is formed over the entire length of the sheath 21 between the shaft 22 and the sheath 21, that is to say between the outer surface of the shaft 22 and the helical strand 70 inside. This radial space 25 between the shaft 22 and the sheath 21 makes it possible to avoid premature wear of the shaft 22, in particular when the tubular assembly 14 is bent.

Preferably, the flexible sheath 21 comes into contact with the cylindrical internal wall of the sleeve 15.

The tubular sleeve 15 is connected to the tube 6 by connection means 26, 27 adapted on the one hand to secure the ends 18, 12 of these tube 6 and sleeve 15 while ensuring the tightness and continuity of their external surface 16, 17 and, on the other hand, to hold the corresponding end 29 of the sheath 21 relative to the tube 6 and to the sleeve 15.

In the first variant shown in FIG. 5a, the means 26, 27 for connecting the tube 6 and the sleeve 15 are means for fitting and crimping a male end piece 26 into a female end piece 27.

In this variant shown in FIG. 5a, the male endpiece 26 is formed by a metal sleeve defining a cylindrical groove 73 for receiving and crimping the end 18 of the sleeve 15 and the end 29 of the flexible sheath 21. The metal socket 26 covers these ends 18, 29 which it receives between two cylindrical walls 74, 75 defining between them the groove 73. These walls 74, 75 are connected together by a connecting wall 76 in the form of a crown and of section transverse (by a radial plane) curved so that the outer wall 75 approaches the inner wall 74 by reducing the curvature of the wall link 76 during crimping. Thus, the ends 18, 29 are tightened radially together in the groove 73. The external wall 75 comprises ribs 77 projecting inwards (towards the internal wall 74) to penetrate into the thickness of the sleeve 15, the the end 18 is crushed by the crimping. In the variant of FIG. 5a, the sleeve 26 is placed at the ends 18, 29 of the sleeve 15 and of the sheath 21, then the assembly is introduced into the end of the tube 6 forming a female end piece 27, on which a radial pressure inward using a crimping tool to secure the assembly.

In the variant embodiment of FIG. 5b, the connection means also comprise a metal socket 78 similar to that of the variant of FIG. 5a, and defining the cylindrical groove 73 for receiving and crimping the ends 18, 29 with a wall external 80 provided with crimping ribs 82, an internal wall 79 and a connecting ring 81. However, in this variant, the socket 78 constitutes a connecting piece interposed between the sleeve 15 and the tube 6. The crown 81 is in fact provided with a thread suitable for being screwed into a thread 83 at the end of the tube 6. In this variant, the crimping pressure is exerted directly on the external wall 80 of the socket 78.

In the two variants of the connection means, the sleeve 15 and / or the sheath 21 and / or the sleeve 26, 78 and / or the tube 6 can also be bonded to each other during assembly. Each of the bearings 10, 11 carrying and guiding the eccentric body 9 in the tube 6 is a ball bearing. The eccentric body 9 extends between two pins 32, 33 carried by the inner cages 36, 37 of the two bearings 10, 11. The two bearings 10, 11 are placed in the tube 6 with their axes of rotation aligned one with the other and with the main axis of symmetry of the tube 6.

Between the two pins 32, 33, the eccentric body 9 comprises a central cylindrical core 38 guided by the two pins 32, 33. The central core 38 and the two pins 32, 33 are formed by a cylindrical bar which extends over the entire length of the tube 6 between the two bearings 10, 11. A portion 84 d 'a section of cylindrical tube is attached and fixed to the core 38 to form an imbalance around the axis of rotation of the core 38 defined by the bearings 10, 11. This portion 84 is not symmetrical in revolution and is preferably a half (cut by an axial diametral plane) of cylindrical tube section, as shown in FIG. 10, the internal diameter of which corresponds to the external diameter of the core 38. This portion 84 formed of a heavy metal, for example in steel, is simply welded to the core 38 by weld beads 85 (FIG. 10) and / or fixed by any other means (screws, glue, etc.) to the core 38.

The body 9 thus formed has a cross section which is generally in the form of an angular sector between 90 ° and 180 °, preferably equal to 180 °. In this way, the center of gravity of the body 9 is distant from the main axis of symmetry of the tube 6 and therefore from the axis of rotation of the pins 32, 33.

One 33 of the two pins is coupled to the end 24 of the flexible shaft 22. Thus, according to the invention, the flexible shaft 22 is directly coupled to the eccentric body 9. Advantageously and according to the invention, the pin 33 has a bore receiving the end 24 of the shaft 22. The assembly is secured in rotation for example by crimping the pin 33 on the end 24 (the pin 33 being crushed at using pliers against the end 24) and / or bonding. This assembly of the pin 33 to the shaft 22 not only makes it possible to secure in rotation the shaft 22 and the pin 33, but also to maintain them in their axial position relative to each other. The inner cages 36, 37 of the bearings 10, 11 are fixed on the pins 32, 33, and the outer cages 34, 35 of the bearings 10, 11 are inserted in the tube 6 with, at least during assembly, a IO sufficient radial clearance to allow the relative axial movement of the bearings 10, 11 in the tube 6 during assembly. After mounting, the outer cages 34, 35 of the bearings may be integral with the tube 6 in the case where a force mounting and / or bonding of the cages 34, 95 to the tube 6 is used. Nevertheless, a radial clearance between the cages 34, 35 and the tube 6 can be kept after mounting in operation. It has in fact been found that such a radial clearance is not only not harmful in operation, but on the contrary can be beneficial from the point of view of vibratory efficiency. It should be noted, moreover, that the bearings 10, 11 in the tube 6 have large dimensions and are chosen to resist with a sufficient service life to the significant vibrations generated by the body 9.

For mounting the tubular sleeve 15 on the drill 1, the rigid head 19 comprises an external casing 39, a fixing piece 40 assembled to the casing 39 in a removable manner and receiving the end 20 of the sleeve 15 and the end 41 of the sheath 21. To do this, the fixing piece 40 comprises a cylindrical housing 42 for receiving and crimping the end 20 of the sleeve 15 and the end 41 of the sheath 21, this cylindrical housing 42 comprising ribs 86 s extending inwardly projecting from an external wall 87 of the cylindrical housing 42 to penetrate into the thickness of the sleeve 15. The fixing piece 40 further comprises an internal cylindrical wall 88 extending opposite the external cylindrical wall 87 to define between them the cylindrical housing 42. To assemble the assembly, the end 20 of the sleeve 15 and that 41 of the sheath 21 are introduced into the cylindrical housing 42, then the assembly is crimped nt radially inwardly the outer wall 87 using a crimping tool. Advantageously, the end 41 of the sheath 21 and / or the end 20 of the sleeve 15 is advantageously glued to the interior of the cylindrical housing 42, so as to form a sealed assembly. The fixing part 40 is assembled to the casing 39 by any removable assembly means (threading of the part 40 and tapping of the casing 39; one or more radial locking screws; bayonet-type mounting, etc.). The housing 39 of the rigid head 19 is tightened on the neck 44 of the drill 1 by means of an assembly collar 45 or by any other rapid assembly means.

The end 23 of the shaft 22 is coupled to the output pin 4 of the drill 1 by means of junction means 46, 47 comprising a coupling part 46 mounted integral in rotation by crimping at the end 23 of the shaft 22, and an adapter part 47 arranged so as to connect and couple the coupling part 46 to the output pin 4 of the drill 1. The coupling part 46 is assembled and coupled in rotation at the end 23 of the shaft 22 by crimping and if necessary, by bonding. This assembly also has the function of maintaining the relative axial positions of the coupling piece 46 relative to the end 23 of the shaft 22. The coupling piece 46 comprises a bore receiving the end 23 of the shaft 22. This bore is crimped on the end 23 by clamping using pliers or a similar tool, and optionally glued.

The coupling piece 46 defines a receiving housing 89 for the adapter piece 47, this receiving housing 89 and the adapter piece 47 having conjugate shapes adapted to prevent any relative rotation and to ensure the rotation coupling of the adaptation piece 47 relative to the coupling piece 46. In the alternative embodiment shown in FIGS. 3a and 4, the coupling piece 46 is formed by a cylindrical flywheel extending radially in the majority of the radial space provided by the casing 39 in the head 19. The receiving housing 89 is formed by a parallelepipedal radial recess 89 centered on the axis and at the end of the part coupling 46, and the adaptation piece 47 is parallelepipedal in order to be able to fit into this recess 89. The flywheel formed by the coupling piece 46 makes it possible to dampen the vibrations between the shaft 22 and the motor output pin 4, the guide bearing of which is thus preserved.

The adaptation piece 47 comprises a tapping 50 receiving the thread of the spindle 4. The adaptation piece 47 is chosen with its tapping 50 as a function of the drill 1 with which the device must be associated, that is to say say according to the diameter and the pitch of the thread of the output pin 4. The same applies to the dimensions and the shape of the casing 39 and of the collar 45, which are adapted to those of the neck 44 of the drill 1. The adapter piece 47 is thus detachably coupled to the coupling piece 46, and to the output pin 4 of the drill 1.

In the alternative embodiment of the joining means shown in FIGS. 3b and 11, said joining means comprising a coupling piece 53 mounted in rotation, by crimping, at the end 23 of the shaft 22, and coupled to the spindle outlet 4 by removable means of rotation coupling; and at least one access port 90 formed through the casing 39 of the rigid head 19 opposite the outlet pin 4 for mounting and coupling the coupling piece 53 on the outlet pin 4.

In FIG. 3b, said removable means for rotationally coupling are formed by the thread of the output spindle 4 of the drill 1 and by a blind thread 91 formed in the coupling part 53 whose external surface is adapted (for example with hexagon) to allow it to be tightened using a tool (open-end wrench for example) inserted through the light 90 adapted for this purpose.

In the embodiment shown in Figure 11, the device is not of the type intended to be associated with a portable drill, but incorporates on the contrary, an electric drive motor 51 comprising an output pin 52 coupled to the end 23 of the shaft 22 by the coupling piece 53. The motor 51 is of the single-phase alternating type and rotates at a rotational speed less than 5000 rpm, especially between 2500 rpm and 3500 rpm. In the variant shown of the joining means, the coupling piece 53 is crimped, and optionally glued to the end 23 of the shaft 22. The coupling piece 53 is mounted for rotation with the spindle 52 by splines parallel to the axis formed on the spindle 52 and on a bore 92 of the coupling part 53, and by a radial split pin 93 accessible through the slot 90. The rigid head 19 also comprises an outer casing 54 which, in the variant shown in Figure 11 is also the housing containing the motor 51. An access port 90 is provided through this housing 54 for the assembly or disassembly of the joining means. Also, there is provided a fixing piece 40 of the end 20 of the sleeve 15 and of the sheath 21 relative to the casing 54. In this embodiment, the fixing piece 40 is preferably fixed in a non-removable manner on the casing 54 of the rigid head 19, for example by punching and / or πvetage and / or bonding ...

In the variant of FIG. 11, the casing 54 is generally cylindrical and contains and carries the motor 51. In the variant of FIG. 2, a larger casing 62 is provided from the rigid head 19 to enclose the motor 51. The casing 54 or 62 of the motor 51 also carries two handles 55 for handling the device, as well as a button 56 for controlling the operation of the motor 51.

As can be seen in FIG. 1, if the end plug 8 of the tube 6 and / or the tube 6 encounters an armature or an obstacle in the mass of material during the introduction of the vibrating needle 5, the tubular sleeve 15 and the tubular assembly 14 can flex, so that the tube 6 is deflected and avoids said frame or said obstacle. The same phenomenon occurs if the plug end 8 meets a formwork wall, especially if the mass of material has shapes that are not perfectly straight.

The tubular sleeve 15 has a length between 1 and 10 times the length of the tube 6. Advantageously, the length of the sleeve 15 is between 250mm and 2000 mm, and in particular of the order of 500 mm, for a length of the tube 6 between 200 mm and 400 mm, in particular between 250 mm and 350 mm. In this way, the engine block of the drill 1 and the handling means 2, 3 are located at working height generally at the level of the hands of the user in the standing position.

The invention can be the subject of other alternative embodiments and the various embodiments and variants described above can be combined or permuted.

EXAMPLES:

Vibration tests of cylindrical concrete specimens 12 cm in diameter and 24 cm in height were carried out for identical durations, with a state-of-the-art apparatus (hereinafter referred to as ET), of professional type. manufactured by the company STV (FRANCE) of reference EDY (with three-phase electric motor, vibrating needle with pendulum rotary member driven at more than

10,000 rpm and flexible transmission of small diameter about 2 m in length), and with two devices according to the invention in accordance with the first embodiment

(Figure 1) coupled to an 800 W electric drill, one of which, hereinafter designated F25, has an external diameter of the tube 6 of 25 mm, and the other, hereinafter designated F33, has an external diameter of tube 6 of 33 mm. In the two devices F25 and F33, the sleeve 15 has a length of 30 cm and a diameter corresponding to that of the tube 6, and the tube 6 has a length of 32 cm. The electric motor and the eccentric body 9 rotate at 2500 rpm for the device F25 and 3000 rpm for the device F33.

The tests focused on three different concretes, the constituents and characteristics of which are as follows.

The density of vibrated concrete specimens is measured in the fresh state and in the hardened state (after one day demoulding and maintenance 28 days at 20 ° C under 100% relative humidity. The compressive strength to l The hardened state was also measured according to the AFNOR NF P18-406 standard Each test was carried out simultaneously on three test pieces.

The following table provides the results obtained on average

As can be seen, the devices according to the invention are as efficient as the professional device of the prior art, the density differences being less than 1%, the compressive strength even being slightly improved.

Claims

CLAIMS 1 / - Needle type apparatus for producing vibrations with a view to compacting a mass of materials, in particular concrete, characterized in that it comprises in combination: a) a tube (6) closed at the one (7) of its ends, b) an eccentric body (9) of elongated shape, rotatably mounted in the tube (6), c) two bearings (10, 11) housed inside the tube (6), one near its closed end (7) the other near its other end (12), so as to guide the eccentric body (9) in rotation, d) a tubular sleeve (15) extending the tube ( 6), of external diameter substantially identical to that of said tube (6), this sleeve (15) having a resistance in axial compression and a shape adapted to allow the introduction of the tube (6) within said mass of materials, but an appropriate flexibility to allow its bending in the case where resistance is encountered during the introduction, e) a flexible sheath (21) contained in the sleeve (15), and comprising at least two helical strands wound in opposite directions, coaxial, one inside the other, surrounded by an external tubular covering, f) a flexible transmission shaft (22) contained in the flexible shaft (21) and coupled to the eccentric body (9) to be able to cause it to rotate, g) means (26, 27, 78) for connecting the tube (6) and the sleeve (15), adapted, on the one hand, to secure the ends (12, 18) of these tubes (6) and sleeve (15) by ensuring at least substantially continuity of their external surfaces (16, 17), on the other hand, to maintain the end (29) of the sheath (21) relative to said tube (6) and sleeve (15), h) a rigid head (19) for fixing the other end (20, 41) of the sleeve (15) and the sheath (21), equipped with means (46, 47 , 53) junction allowing to couple the shaft (22) to an output pin (4, 52) of an electric rotation drive motor associated with means (2, 3, 55, 56) for handling the device.

2/ - Apparatus according to claim 1, characterized in that the sleeve (15) is made of synthetic material.

3/ - Apparatus according to one of claims 1 and 2, characterized in that the length of the sleeve (15) is between 1 time and 10 times the length of the tube (6).

4/ - Apparatus according to claim 3, characterized in that the length of the sleeve (15) is between 250 mm and 2000 mm, in particular of the order of 500 mm. 5/ - Apparatus according to one of claims 1 to 4, characterized in that said means for connecting the tube (6) and the sleeve (15) are means for fitting and crimping a male end (26) into a female end (27). 6/ - Apparatus according to one of claims 1 to 5, characterized in that said connection means comprise a connecting piece (78) interposed between the sleeve (15) and the tube (6).

7/ - Apparatus according to one of claims 5 and 6, characterized in that the connection means define a cylindrical groove for receiving and crimping the end (18) of the sleeve (15) and the end (29 ) of the flexible sheath (22), and in that this cylindrical groove comprises ribs projecting inwards from an external wall of the cylindrical groove to penetrate into the sleeve (15)

8/ - Apparatus according to one of claims 1 to 7, characterized in that said joining means comprise: - a coupling part (46) mounted integrally in rotation by crimping at the end (23) of the shaft (22),

- an adaptation piece (47) arranged with so as to connect and couple the coupling part (46) to the output pin (4), this adaptation part (47) being coupled in rotation to the output pin (4) by screwing, the part of coupling (46) defining a receiving housing (89) of the adaptation part (47), this receiving housing (89) and the adaptation part (47) having combined shapes adapted to prohibit any relative rotation and ensure the rotational coupling of the adaptation part (47) relative to the coupling part (46).

9/ - Apparatus according to one of claims 1 to 7, characterized in that said joining means comprise:

- a coupling part (53) mounted integrally in rotation by crimping at the end (23) of the shaft (22), and coupled to the output pin (4) by removable rotational coupling means,

- at least one access port (90) provided through the rigid head (19) facing the output pin (4) for mounting and coupling the coupling part (53) on the output pin (4).

10/ - Apparatus according to one of claims 1 to 9, characterized in that the rigid head (19) comprises a casing (39, 54), and a fixing part (40) of the end (20) of the sleeve (15) and (41) of the sheath (21) relative to the casing (32, 54).

11/ - Apparatus according to claim 10, characterized in that the fixing part (40) is rigidly associated with the rigid head (19) and defines a cylindrical housing (42) for receiving and crimping the end (20) of the sleeve (15) and the end (41) of the flexible sheath (21), this cylindrical housing (42) comprising ribs (86) extending inwardly from an external wall ( 87) of the cylindrical housing (42) to penetrate the thickness of the sleeve (15).

12/ - Apparatus according to one of claims 1 to 11, characterized in that the tube (6) is closed by a cap (8) of rounded shape, mounted immovably at the end (17) of the tube (6)

13/ - Apparatus according to one of claims 1 to 12, characterized in that the eccentric body (9) is coupled to the end of the shaft (22) by crimping.

14/ - Apparatus according to one of claims 1 to 13, characterized in that each bearing (10, 11) is a bearing, in that the eccentric body (9) comprises two pins (32, 33) carried by the cages internal (36, 37) of the two bearings, and in that one of the journals (32, 33) is directly coupled to the end (24) of the shaft (22) - in particular by crimping.

15/ - Apparatus according to claim 14, characterized in that ^•

- the inner cages (36, 37) of the bearings (10, 11) are fixed on the pins (32, 33),

- the outer races (34, 35) of the bearings (10, 11) are inserted into the tube (6) with radial clearance.

16/ - Apparatus according to one of claims 1 to 15, characterized in that the eccentric body (9) comprises a central cylindrical core (38) guided by the bearings (10, 11), and a portion (84) of cylinder -in particular a half-cylinder- fixed attached to the core (38) to form unbalance around the axis of rotation of the core (38) defined by the bearings (10, 11).

17/ - Apparatus according to one of claims 1 to 16, characterized in that the flexible sheath (21) comes into contact with the cylindrical internal wall of the sleeve (15) and in that the shaft (22) is mounted in the flexible sheath (21) with radial play.

18/ - Apparatus according to one of claims 1 to 17, characterized in that the electric motor is adapted to drive the output spindle

(4) and the eccentric body (9) at a rotation speed less than 5000 revolutions/mm, in particular between 2500 and 3500 rpm.