Accessory for portable electrical appliance

Abstract

Title: Accessory for portable electric appliance Monolithic accessory (3), made of metal, intended to be removably attached to a portable electric appliance (2), in particular a perforator, said accessory comprising a connecting shaft (10), a quick-attachment interface (5) to a portable electric appliance, and a working head (11), the quick-attachment interface being positioned on a first side of said connecting shaft, the working head being positioned on a second side of said connecting shaft, the working head comprising a flat or substantially flat contact face (12), said contact face extending perpendicular to the connecting shaft, said contact face being intended to be applied against a formwork element (21) to vibrate concrete (22) in the liquid state, the working head comprising a cross-section increasing from said connecting shaft to said contact face. Figure to be published with the abstract: Figure 3

Description

Title of the invention: Accessory for portable electrical appliance Technical field of the invention

[0001] The invention relates to the field of accessories for portable electric devices such as drills. The invention also relates to a vibration generator comprising such an accessory. The invention also relates to a masonry method comprising vibrating a formwork element by means of such a vibration generator. Finally, the invention also relates to a method for fixing a threaded shaft by means of such a vibration generator. State of the prior art

[0002] In the field of masonry, it is common to pour liquid concrete into a formwork in order to construct a concrete structure of a given shape. To do this, a formwork is constructed and then the liquid concrete is poured into the formwork. The formwork sometimes has complex geometric shapes and the liquid concrete has a very high viscosity. Under these conditions, the liquid concrete has difficulty reaching all areas of the formwork. Sometimes certain areas of the formwork are poorly filled with liquid concrete. The resulting concrete structure is then incomplete.

[0003] To overcome this drawback, it is known to use vibrating needles which are immersed directly into the concrete in the liquid state. The vibrating needles are connected by a flexible connector to a portable electric device which vibrates the needle. The vibrating needles transmit vibrations to the concrete in the liquid state, which promotes its complete distribution in the formwork.

[0004] Vibrating needles do, however, have drawbacks: They do not always allow all areas of the formwork to be reached, especially when the latter has a complex shape. They are bulky and difficult to handle. They require careful cleaning after each use to prevent concrete from drying on their surface. Presentation of the invention

[0005] The aim of the invention is to provide an accessory for a portable electrical appliance which overcomes the above drawbacks.

[0006] More specifically, an object of the invention is an accessory, suitable for use with a portable electric device, which makes it possible to vibrate concrete in the liquid state in a simple and ergonomic manner, so that the concrete in the liquid state reaches all areas of a formwork to construct a concrete structure of complex shape. Summary of the invention

[0007] The invention relates to a monolithic accessory, made of metal, intended to be removably attached to a portable electric appliance, in particular a perforator, said accessory comprising a connecting shaft, a quick-attachment interface to a portable electric appliance, and a working head, the quick-attachment interface being positioned on a first side of said connecting shaft, the working head being positioned on a second side of said connecting shaft, the working head comprising a flat or substantially flat contact face, said contact face extending perpendicular to the connecting shaft, said contact face being intended to be applied against a formwork element to vibrate concrete in the liquid state, the working head comprising a cross-section increasing from said connecting shaft to said contact face.

[0008] The working head may comprise a symmetry of revolution around an axis of revolution, and said contact face may comprise the shape of a disc.

[0009] The contact face may comprise a diameter of between 2cm and 5cm inclusive, in particular between 3cm and 4cm inclusive, and the accessory may comprise a total length along said axis of revolution of between 6cm and 25cm inclusive, in particular between 6cm and 10cm inclusive.

[0010] The working head may comprise: - a first portion of truncated cone shape, then - a second portion of cylindrical shape, then - a third portion of concave truncated cone shape, then - a fourth portion of cylindrical shape.

[0011] The contact face may comprise a central recess whose depth is less than or equal to 0.5 cm, and whose diameter is between 0.5 cm and 2 cm inclusive, in particular between 0.8 cm and 1.2 cm inclusive.

[0012] The Accessory may comprise a chamfer extending over the entire periphery of the contact face.

[0013] The quick-fixing interface may be an SDS Plus type fixing interface.

[0014] The invention also relates to a vibration generator for vibrating a formwork element for vibrating concrete in the liquid state comprising a portable electric device, in particular a perforator, the portable electric device comprising a hammer capable of transmitting cyclic pulses parallel to a working axis, the vibration generator further comprising an accessory as defined previously, said accessory being removably attached to the portable electric device so as to vibrate parallel to its connecting axis.

[0015] The invention also relates to a masonry method, comprising, - the installation of at least one formwork element delimiting a volume to be filled with concrete, in particular said element being made of wood, then - pouring concrete in the liquid state into said volume, then - vibrating said formwork element using a vibration generator as defined previously.

[0016] The invention also relates to a method of fixing a threaded shaft in a structure, comprising: - the application of a force on said threaded axis by means of a vibration generator as defined previously, via the contact face of the accessory, and simultaneously - vibrating said threaded shaft using the vibration generator. Presentation of figures

[0017] These objects, characteristics and advantages of the present invention will be explained in detail in the following description of a particular embodiment made without limitation in relation to the attached figures among which:

[0018] [Fig.l] is a schematic view of a vibration generator equipped with an accessory according to one embodiment of the invention.

[0019] [Fig.2] is a schematic side view of an accessory according to one embodiment of the invention.

[0020] [Fig.3] is a perspective view of the accessory of [Fig.2].

[0021] [Fig.4] is a perspective view of a quick-attach interface of the accessory of [Fig.2].

[0022] [Fig.5] is a schematic view of a formwork filled with concrete in the liquid state, the vibration generator of [Fig.l] being used to vibrate said formwork.

[0023] [Fig. 6] is a schematic view of a structure, the vibration generator of [Fig. 1] being used to drive a threaded shaft into said structure. Detailed description

[0024] [Fig.l] schematically illustrates a vibration generator 1 according to one embodiment of the invention. The vibration generator 1 comprises a portable electric device 2 and an accessory 3 according to one embodiment of the invention.

[0025] In particular, the portable electric device 2 is a perforator. A perforator is a device intended to drill holes in hard materials such as concrete, stone or even ceramic. A perforator is conventionally intended to be used with a drill bit, or alternatively with a chisel. The perforator comprises a quick-fixing means 4 configured to removably fix an accessory to the perforator. The quick-fixing means is preferably an "SDS" type fixing means, in particular an "SDS Plus" fixing means, SDS being the acronym for "Special Direct System". Such a fixing means may in particular comply with the fixing means described in publication DE2551125A1. Alternatively, the quick fixing means could also be of the "SDS Max" type or even be a quick fixing means complying with any standard used for the quick fixing of an accessory to a portable power tool.

[0026] The perforator further comprises a hammer configured to transmit cyclic pulses parallel to a working axis X of the perforator. Each pulse may comprise an energy of between 1 and 30 joules. The frequency of the pulses may be between 500 and 4000 pulses per minute. The perforator may also comprise an electric motor configured to rotate an accessory around the working axis X. In such a case, the perforator preferably comprises a control means configured to deactivate the rotation of the accessory. The perforator also comprises an electrical energy supply means for setting the hammer in motion. In particular, the perforator may comprise an electrochemical battery and / or be intended to be connected to an electrical energy distribution network by means of an electric cable.

[0027] The accessory 3 is notably shown in figures 1 and 2. The accessory 3 is a monolithic part, that is to say a part made up of a single block of material. The accessory 3 is therefore not made up of the assembly of several parts fixed or welded to each other. The accessory 3 is made of metal, preferably steel. The accessory 3 can advantageously be obtained by turning a metal block. Alternatively, the accessory 3 could also be obtained by forging. Other metallurgical manufacturing processes could be envisaged. Advantageously, the accessory can be subjected to a heat treatment and / or a surface treatment, in particular in order to be hardened.

[0028] The accessory 3 is removably attached to the portable electric appliance so as to vibrate parallel to the working axis X. The accessory 3 comprises a quick-fixing interface 5 compatible with the quick-fixing means 4 of the portable electric appliance 2. In this case, the accessory 3 therefore comprises a quick-fixing interface 5 of the "SDS Plus" type. The accessory 3 can therefore be quickly and simply attached to or detached from the portable electric appliance, without any special tools.

[0029] The quick-fixing interface 5 is illustrated in particular in more detail in [Fig. 4]. The quick-fixing interface 5 may comprise a generally cylindrical shape with a diameter DI equal to 10 mm, and a length L1 of, for example, between 50 mm and 60 mm inclusive. The quick-fixing interface 5 comprises two first grooves 6 extending parallel to the working axis X, diametrically opposed, and opening onto a rear face 8 of the accessory 3. The first grooves 6 may comprise a length of approximately 25 mm along the working axis X. The quick-fixing interface 5 also comprises two second grooves 9 extending parallel to the working axis X, diametrically opposed, and not opening onto the rear face 8 of the accessory 3. The second grooves 9 may comprise a length of approximately 12 mm along the working axis X. The two second grooves 9 are positioned on either side of the two first grooves 6. The grooves 6 and 9 are distributed around the cylindrical shape of the quick-fixing interface 5 and are therefore spaced apart by an angle of approximately 90°.

[0030] The accessory 3 also comprises a connecting shaft 10 extending from the quick-fixing interface 5 along the working axis X. The connecting shaft 10 comprises a cylindrical shape whose diameter may be, for example, between 10 mm and 12 mm inclusive. The accessory 3 also comprises a working head 11 connected to the quick-fixing interface 5 via the connecting shaft 10. The quick-fixing interface 5 is therefore positioned on a first side of the connecting shaft 10, and the working head 11 is positioned on a second side of the connecting shaft 10, opposite the first side.

[0031] The working head 11 comprises a flat or substantially flat contact face 12. The contact face 12 extends perpendicular to the connecting axis 10, i.e. perpendicular to the working axis X.

[0032] The working head 11 comprises a symmetry of revolution around an axis of revolution. The working head can thus easily be manufactured by a turning process. The contact face 12 thus comprises the shape of a disc. The axis of revolution coincides with the working axis X. Thus, hereinafter, the axis X designates both the working axis and the axis of revolution of the working head 11.

[0033] The contact face 12 comprises a diameter D2 of between 2cm and 5cm inclusive, in particular between 3cm and 4cm inclusive, for example equal to 3.5cm. The accessory 3 comprises a total length L2 along said working axis X of between 6cm and 25cm inclusive, in particular between 6cm and 15cm inclusive, preferably between 6cm and 10cm, for example equal to 8cm.

[0034] The working head 11 comprises a cross-section increasing from the connecting axis 10 to the contact face 12. A cross-section designates a section of the accessory 3 perpendicular to the working axis X. By "increasing", it is understood that the surface of the cross-section is stable or increasingly larger as one approaches the contact face 12.

[0035] More particularly, the working head 11 can be broken down into four consecutive portions 13, 14, 15, 16 along the working axis X. The first portion 13, more on the side of the quick-fixing interface 5, comprises a truncated cone shape. The second portion 14, positioned between the first portion 13 and the third portion 15, comprises a cylindrical shape. The second portion 14 therefore comprises a constant cross-section. The third portion 15, positioned between the second portion 14 and the fourth portion 16, comprises a concave truncated cone shape. A generatrix of the third portion 15 therefore comprises a curved shape whose center of curvature is positioned outside the working head 11. Finally, the fourth portion 16 also comprises a cylindrical shape. The fourth portion opens onto the contact face 12. The diameter of the fourth portion 16 is equal to the diameter D2 of the contact face 12. Such a shape makes it possible to achieve a very good compromise between ease and speed of manufacturing the accessory by turning and robustness of the accessory.

[0036] As can be seen in [Fig. 3], the contact face 12 advantageously comprises a central recess 17 whose depth (along the working axis X) is less than or equal to 0.5 cm, and whose diameter D3 is between 0.5 cm and 2 cm inclusive, in particular between 0.8 cm and 1.2 cm inclusive, for example equal to 1 cm. Such a recess allows the accessory to be used in a more ergonomic manner to fix a threaded shaft in a structure. The central recess 17 has a small depth. The working head remains essentially filled with material. Thus, by "substantially flat", it is understood that the contact face 12 can have such a central recess 17 of small depth. The accessory 3 is very different from a hole saw in which the central recess is much larger. Alternatively, the accessory 3 could not include such a central recess and the contact face would then be completely flat.Furthermore, the accessory 3 also comprises a chamfer 18 extending over the entire periphery of the contact face 12.

[0037] [Fig. 5] schematically illustrates a first mode of use of the vibration generator 1 according to the invention. A formwork 20 comprises five formwork elements 21 assembled together in order to manufacture a concrete structure of relatively complex shape. The formwork elements 21 may, for example, be wooden planks. The formwork 20 is filled with concrete 22 in the liquid state from an opening 23 arranged in the upper part of the formwork 20. The assembly of the formwork elements 21 forms a cavity 24 which is difficult to access from the opening 23. Due to the high viscosity of the concrete in the liquid state, the liquid concrete does not naturally manage to fill the entire cavity 24. Advantageously, the vibration generator as described above is used to vibrate a formwork element 21 to vibrate the concrete 22 in the liquid state.To do this, the hammer of the drill is activated, which causes the accessory to vibrate parallel to the working axis X. The contact face 12 is then pressed against a formwork element 21. The vibrations are transmitted to the concrete 22 in the liquid state. This promotes good flow and good distribution of the concrete throughout the volume of the formwork 20. This therefore makes it possible to fill the cavity 24 with liquid concrete. As indicated by an arrow Fl in [Fig.5], the concrete in the liquid state rises in the cavity 24 thanks to the action of the generator. of vibrations 1. Accessory 3 is not intended to be put in direct contact with the liquid concrete but only with the formwork, accessory 3 and more generally the entire vibration generator 1, is therefore not soiled by liquid concrete.

[0038] The particular shape of the accessory 3 which has just been described makes it possible to effectively vibrate the formwork 20 without damaging it. No hole is drilled in the formwork during this operation. The formwork elements are thus preserved and can possibly be reused subsequently. The massive nature of the accessory 3 makes it possible to effectively transmit the vibrations generated by the hammer integrated into the perforator.

[0039] Advantageously, the presence of the chamfer 18 around the contact face 12 makes it possible to avoid a phenomenon of drift or shifting of the working zone when pressure is exerted with the vibration generator 1. Advantageously, the perforator is used without rotation of the accessory around the working axis X.

[0040] The relatively small dimensions of the accessory 3 allow access to formwork elements 21 that are difficult to access, in particular corners formed between two formwork elements. It is therefore possible to vibrate the liquid concrete precisely at the locations where the concrete has difficulty flowing. In addition, when the operation of vibrating the liquid concrete is finished, the accessory 3 can easily be detached from the perforator and stored in a pocket.

[0041] [Fig. 6] schematically illustrates a second mode of use of the vibration generator 1 according to the invention. According to this second mode of use, the vibration generator 1 is used to fix a threaded shaft, in particular a stud 25, in a structure 26, in particular a concrete structure. The stud 25 may in particular comprise a threaded shaft 27 and a head 28. The stud 25 is partially inserted into a hole previously formed in the structure. The hole may be equipped with a dowel. To insert the stud into the hole, a force is applied along the working axis X against the head 28 of the stud 25, by means of the vibration generator 1 via the contact face 12 of the accessory 3. Simultaneously, the stud 25 is vibrated with the vibration generator 1. The stud then very easily sinks inside the hole. This operation does not require screwing the stud 25 into the hole.The stud 25 is driven in a translational movement. The use of an accessory 3 having a central recess 17 is advantageous for carrying out this operation because the central recess 17 makes it possible to center the accessory with the head of the stud. For this operation, the perforator can be used without rotation of the accessory 3 around the working axis X or with rotation of the accessory around the working axis X in the screwing direction.

Claims

Claims

1. Monolithic accessory (3), made of metal, intended to be removably attached to a portable electric appliance (2), in particular a perforator, said accessory comprising a connecting shaft (10), a quick-attachment interface (5) to a portable electric appliance, and a working head (11), the quick-attachment interface being positioned on a first side of said connecting shaft, the working head being positioned on a second side of said connecting shaft, the working head comprising a flat or substantially flat contact face (12), said contact face extending perpendicular to the connecting shaft, said contact face being intended to be applied against a formwork element (21) to vibrate concrete (22) in the liquid state, the working head comprising a cross-section increasing from said connecting shaft to said contact face.

2. Accessory (3) according to the preceding claim, characterized in that the working head (11) comprises a symmetry of revolution around an axis of revolution (X), and in that said contact face (12) comprises the shape of a disc.

3. Accessory (3) according to the preceding claim, characterized in that the contact face (12) comprises a diameter (D2) between 2cm and 5cm inclusive, in particular between 3cm and 4cm inclusive, and in that the accessory comprises a total length (L2) along said axis of revolution (X) between 6cm and 25cm inclusive, in particular between 6cm and 10cm inclusive.

4. Accessory (3) according to one of the preceding claims, characterized in that the working head comprises: - a first portion (13) of truncated cone shape, then - a second portion (14) of cylindrical shape, then - a third portion (15) of concave truncated cone shape, then - a fourth portion (16) of cylindrical shape.

5. Accessory (3) according to one of the preceding claims, characterized in that the contact face (12) comprises a central recess (17) whose depth is less than or equal to 0.5cm, and whose diameter (D3) is between 0.5cm and 2cm inclusive, in particular between 0.8cm and 1.2cm inclusive.

6. Accessory (3) according to one of the preceding claims, characterized in that it comprises a chamfer (18) extending over the entire periphery of the contact face (12).

7. Accessory (3) according to one of the preceding claims, characterized in that the quick-fixing interface (5) is a SDS Plus type fixing interface.

8. Vibration generator (1) for vibrating a formwork element (21) for vibrating concrete (22) in the liquid state comprising a hand-held electric device (2), in particular a drill, the hand-held electric device comprising a hammer capable of transmitting cyclic pulses parallel to a working axis (X), the vibration generator further comprising an accessory (3) according to one of the preceding claims, said accessory being removably attached to the hand-held electric device so as to vibrate parallel to its connecting axis (10).

9. Masonry method, comprising, - the installation of at least one formwork element (21) delimiting a volume to be filled with concrete, in particular said element being made of wood, then - the pouring of concrete (22) in the liquid state into said volume, then - the vibration of said formwork element by means of a vibration generator (1) according to the preceding claim.

10. Method for fixing a threaded shaft (25) in a structure (26), comprising: - applying a force to said threaded shaft by means of a vibration generator (1) according to claim 8, via the contact face (12) of the accessory (3), and simultaneously - vibrating said threaded shaft by means of the vibration generator.

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