Cutting tools used to construct threaded piles in land

Abstract

A cutting tool (20) for constructing a threaded pile (P) includes: a cylindrical hollow core (22); a helical thread (24); a conduit (30) translatably movable within the hollow core and including a lower tube portion (31) having a sidewall (34) in which an inclined groove is formed and an injection hole (35); and a grooving device (50) including grooving teeth (52) movable between a retracted position and an extended position and an engagement portion (60), wherein the cutting tool is configured to switch from a first configuration to a second configuration by relative translational displacement of the conduit relative to the hollow core in the longitudinal direction, the engagement portion being configured to slide within the groove, thereby displacing the grooving teeth between the retracted and extended positions when the cutting tool changes from the first configuration to the second configuration.

Description

Technical Field

[0001] This invention relates to the technical field of cutting tools for constructing threaded piles in soil, particularly using a method known as continuous auger drilling (continuous auger propulsion method). The invention also relates to a machine comprising such cutting tools.

[0002] The cutting tools used in continuous auger drilling to construct threaded piles consist of helical threads mounted on a cylindrical hollow core, allowing the formation of a cylindrical driling hole in the soil. To improve the anchorage of the pile in the soil, these cutting tools are also equipped with slotted teeth, also known as lugs. These slotted teeth must be retractable so that they can be withdrawn during the drilling phase, thus preventing the formation of grooves in the soil during this step. In fact, forming grooves during drilling can lead to instability in the surrounding soil, which impairs the good friction between the shaft of the final threaded pile and the soil at the placement site. During the lifting of the cutting tool, the slotted teeth can be placed in a deployed position to form helical grooves on the inner surface of the cylindrical driling hole.

[0003] Subsequently, the borehole and the grooves formed in its inner surface are immediately filled with concrete. This allows threads to be formed on the pile without destabilizing the surrounding soil, resulting in an increased coefficient of friction between the pile and the soil. Concrete pouring can be performed using a tremie pipe that can be moved translationally inside a hollow core, the tremie pipe being equipped with at least one injection hole. As is known, the tremie pipe can assume a retracted position and an extended position, in which the injection hole is opened outside the hollow core and allows concrete to be injected into the borehole. Background Technology

[0004] Augers are known for forming threaded posts and are equipped with retractable slotted teeth. These augers allow the slotted teeth to unfold as needed (and especially during auger lifting), which facilitates slot formation.

[0005] In particular, a type of auger drill, as described in document FR2889241, is known, comprising a hollow core and a helical thread. This auger also includes a slotted lug in the form of a cam, which is pivotally mounted relative to the hollow core about a vertical axis. The slotted lug is rotatably driven by a motor device (e.g., a hydraulic jack) between a retracted position and an extended position.

[0006] One drawback of this type of auger is that the motor that allows the slotted lug to unfold must be supplied with electrical or hydraulic power. Therefore, the auger's size, weight, and energy consumption are particularly significant. Furthermore, the auger must be equipped with hydraulic lines or cables, typically located inside the hollow core, to supply power to these motors. These lines and / or cables further increase the auger's size. Additionally, it increases the risk of accidents that could impair the proper unfolding of the slotted lug, especially considering the possibility of severed cables and / or hydraulic lines. The motor also requires regular maintenance.

[0007] It is also known that a cutting head (such as document EP2685006) is described, which eliminates the need for a motor device for driving slotted teeth.

[0008] The cutting head described in this document includes a hollow core, within which a translationally movable guide tube is mounted. The cutting head includes a control system comprising a rack fixed to the guide tube and a pinion configured to engage with the rack. During translational displacement of the guide tube relative to the hollow core, the pinion is rotatably driven by the rack. Therefore, the slotted teeth are translated via a connecting rod and a lever connected to the pinion.

[0009] One drawback of this control system is that it includes numerous components prone to wear or breakage, which could impair the proper unfolding of the slotted teeth. Furthermore, the control system requires regular maintenance to prevent jamming of the rack and pinion mechanism. Moreover, this control system is particularly heavy and bulky.

[0010] In addition, prior art document FR2854179 proposes unfolding the slotted teeth during the displacement of the conduit to its lower position. However, this document does not disclose the unfolding scheme of the slotted teeth. Summary of the Invention

[0011] One object of the present invention is to provide a cutting tool for constructing threaded piles in soil, thereby overcoming the above-mentioned disadvantages.

[0012] Therefore, the present invention relates to a cutting tool for constructing threaded piles in soil, the cutting tool comprising: A cylindrical hollow core, the hollow core having a lower end and extending in a longitudinal direction; At least one helical thread, said helical thread being mounted on the outer surface of the hollow core and having an outer peripheral edge; A conduit configured to connect to a fluid (e.g., concrete) supply source and translatably mounted within the hollow core along the longitudinal direction, the conduit comprising at least a lower tube portion having a sidewall in which a groove is formed, at least partially inclined relative to the longitudinal direction, and an injection hole further disposed in the sidewall of the lower tube portion; and A grooving device includes grooving teeth movable between a retracted position and an extended position. In the retracted position, the grooving teeth extend within a cylindrical volume defined by the outer peripheral edge of a helical thread. In the extended position, the grooving teeth protrude beyond the cylindrical volume. The grooving device also includes an engagement portion fixed to the grooving teeth. The cutting tool is configured to present at least a first configuration and a second configuration, the first configuration being referred to as a drilling configuration and the second configuration as an injection configuration. In the first configuration, a conduit is positioned such that the injection hole extends inside the hollow core. In the second configuration, the conduit protrudes from the lower end of the hollow core such that the injection hole extends outside the hollow core. The cutting tool is configured to switch from the first configuration to the second configuration by a relative translational displacement of the conduit relative to the hollow core in the longitudinal direction. The engagement portion of the grooving device is configured to slide within the groove of the conduit, thereby displacing the grooving teeth between a retracted position and an extended position when the cutting tool is brought from the first configuration to the second configuration.

[0013] The cutting tool according to the invention is particularly suitable for constructing threaded piles that extend vertically into the soil. The cutting tool is preferably configured to be assembled with a machine intended for constructing threaded piles in the soil.

[0014] Preferably, the cutting tool allows for the construction of threaded piles in soil using a continuous auger drilling method.

[0015] A auger drill is composed of a hollow core and a helical thread. Preferably, the longitudinal direction of the hollow core remains substantially vertical.

[0016] The hollow core is configured to be rotated about the longitudinal direction. The helical threads mounted on the outer surface of the hollow core are thus rotated, which allows for the formation of a hole.

[0017] The hollow core advantageously has a proximal end configured to engage with a rotating head of a machine designed for constructing threaded piles in soil. The rotating head allows the hollow core to be driven rotatably about its longitudinal direction.

[0018] The conduit extends within the hollow core along the longitudinal direction. Preferably, but not exhaustively, the conduit is prevented from rotating within the hollow core. The hollow core advantageously has an inner shell whose shape corresponds to the shape of the conduit and is configured to accommodate the conduit.

[0019] The conduit has a transverse dimension that is transverse to the longitudinal direction, and the transverse dimension is smaller than the diameter of the hollow core.

[0020] In a non-limiting manner, the lower portion of the catheter may have a circular, rectangular, or square cross-section, or any other polygonal shape. Advantageously, the length of the catheter is greater than the length of the hollow core.

[0021] In a non-limiting manner, the conduit may include several sections. In a non-limiting manner, the sections may have different cross-sections. Preferably, the conduit includes an upper section and a lower section. The upper section of the conduit advantageously has a circular cross-section.

[0022] The conduit is preferably configured to connect to a fluid supply source via a supply conduit that mates with the conduit. The conduit preferably has a proximal end, which is preferably configured to connect to the fluid supply source via a supply conduit. The fluid is preferably concrete or grout. The fluid supply source is preferably a concrete or grout supply source.

[0023] The catheter has an advantageously closed distal end.

[0024] The injection port allows for the injection of fluid, particularly concrete, into the borehole, preferably during the lifting of the cutting tool. Therefore, the fluid is injected in a direction transverse to the longitudinal direction of the hollow core. The fluid is carried to the injection port via the interior of the conduit. The fluid is advantageously delivered from the proximal end of the conduit. The fluid is injected into the borehole from the lower portion of the conduit. The fluid is advantageously injected from a position near the distal end of the conduit. A groove arranged in the sidewall of the lower portion of the conduit has the shape of a slot or channel formed in said sidewall. The groove advantageously has a depth on the order of several centimeters. The groove advantageously has a width on the order of several centimeters.

[0025] The groove advantageously has a length greater than one-quarter of the length of the lower portion of the catheter. Preferably, the length of the groove is greater than half the length of the lower portion of the catheter, more preferably, it is substantially equal to three-quarters of the length of the lower portion of the catheter.

[0026] Although at least a portion of the groove is inclined relative to the longitudinal direction, the groove extends in a general direction parallel to the longitudinal direction of the hollow core. "Inclined" means that at least a portion of the groove is not parallel to the longitudinal direction. In other words, at least a portion of the groove is inclined relative to the vertical direction and is therefore not vertical. In other words, considering the projection into a vertical plane passing through the groove, at least a portion of the groove is inclined relative to the longitudinal direction. Preferably, at least a portion of the groove is parallel to the longitudinal direction of the hollow core.

[0027] Preferably, the groove extends in a vertical plane. Preferably, at least a portion of the groove is inclined relative to a vertical direction considered within the vertical plane.

[0028] Preferably, the lower portion of the catheter has a sidewall comprising multiple lateral faces, and the groove is disposed on one of these lateral faces. Preferably, the catheter comprises a single groove. Preferably, the groove and the injection port are disposed on two different sides of the sidewall.

[0029] Preferably, the groove extends above the injection port. Preferably, the groove extends from the upper part of the lower portion of the conduit. Preferably, the groove extends above the injection port.

[0030] According to a first non-limiting variation, the switching of the cutting tool from a first configuration to a second configuration is achieved by longitudinal displacement of the conduit within the hollow core. Alternatively, according to a second non-limiting variation, the switching of the cutting tool from a first configuration to a second configuration is achieved by longitudinal displacement of the hollow core relative to the conduit. According to another non-limiting alternative, the switching of the cutting tool from a first configuration to a second configuration is achieved by displacement of the conduit and the hollow core relative to each other.

[0031] Preferably, during the relative displacement of the conduit with respect to the hollow core, and therefore during the switch from the first configuration to the second configuration, the distal end of the conduit remains in contact with the soil at the bottom of the borehole, and vice versa.

[0032] In a first configuration, referred to as the borehole configuration, the conduit extends substantially inside the hollow core, preferably substantially entirely within the hollow core. In this first configuration, the conduit is in a retracted position. In this first configuration, the injection port opens into the hollow core and is covered, thereby preventing fluid from being injected into the borehole.

[0033] In the first configuration, the guide tube is advantageously positioned in a higher position. The cutting tool is advantageously positioned in the first configuration during drilling.

[0034] Preferably, but not exhaustively, the conduit includes a cutting tip configured to close the distal end of the conduit. Advantageously, the cutting tip is configured to close the hollow core when the cutting tool is in a first configuration. The cutting tip is advantageously equipped with cutting teeth.

[0035] In a second configuration, referred to as the injection configuration, the conduit extends at least partially beyond the hollow core, such that the injection port is open and unobstructed outside the hollow core. In the second configuration, the distal end of the conduit extends below the lower end of the hollow core. In other words, the conduit then at least partially expands beyond the hollow core. Preferably, when the cutting tool is in the second configuration, the groove extends at least partially beyond the hollow core.

[0036] It should be understood that during the switch from the first configuration to the second configuration (and vice versa), the groove arranged in the sidewall of the lower tube portion of the conduit produces a relative translational movement relative to the hollow core along the longitudinal direction.

[0037] The cutting tool is advantageously positioned in the second configuration during its lifting process.

[0038] The slotted tooth is also called a lug. The slotted tooth is advantageously positioned at the end of the helical thread. In the retracted position, the slotted tooth is retracted. This retracted position corresponds to the resting position, in which the slotted tooth does not protrude and does not contact the inner surface of the bore, thus not forming a groove. During drilling and therefore during the descent of the cutting tool, the slotted tooth is advantageously held in the retracted position.

[0039] In the unfolded position, the slotted teeth protrude beyond the cylindrical volume. The slotted teeth extend radially beyond the outer peripheral edge of the helical thread and thus contact the inner surface of the bore. In this unfolded position, the slotted teeth allow grooves to form in the inner surface of the bore during the displacement of the cutting tool.

[0040] In a non-limiting manner, the joint and the slotted teeth can be formed as an integral assembly. Alternatively, the joint can be a different component from the slotted teeth. The joint is advantageously fixed to the slotted teeth.

[0041] The engagement portion of the grooving device advantageously extends transversely to the grooving teeth. Preferably, but not exhaustively, the grooving teeth have through holes, and the engagement portion extends within the through holes. The engagement portion advantageously has a pin shape, the pin being configured to engage in the groove.

[0042] Preferably, the slotted teeth are mounted on the hollow core or on the helical thread. Preferably, the slotted teeth can translate between a retracted position and an extended position.

[0043] Preferably, the slotted teeth translate between the retracted and extended positions along an unfolding direction that is transverse to the vertical plane passing through the longitudinal direction. The slotting device is advantageously prevented from translating longitudinally.

[0044] Thanks to this invention, during the relative translational displacement of the conduit relative to the hollow core in the longitudinal direction, the engagement portion of the grooving device displaces within the groove. Given the inclination of the groove and the relative displacement of the conduit relative to the grooving device, and more specifically relative to the unfolded portion, the grooving teeth displace between their retracted and unfolded positions. According to the invention, the relative displacement of the conduit relative to the hollow core when the cutting tool moves from a first configuration to a second configuration allows the grooving teeth to unfold or retract.

[0045] More specifically, as long as the groove of the conduit is at least partially inclined relative to the longitudinal direction, the slotted teeth will produce at least a displacement transverse to the longitudinal direction during the sliding of the engagement portion in the inclined portion of the groove. This movement allows the slotted teeth to be displaced until they leave the cylindrical volume defined by the outer peripheral edge of the helical thread.

[0046] During the sliding of the joint in the inclined portion of the groove, the joint is advantageously displaced laterally, taking into account a plane on the sidewall of the lower tube portion through which the groove is arranged.

[0047] It should be understood that when the cutting tool is in the first configuration, the slotted teeth are in the retracted position, and when the cutting tool is in the second configuration, the slotted teeth are in the extended position.

[0048] This invention allows for easy unfolding or retraction of the slotted teeth solely through the relative displacement of the conduit relative to the hollow core. This invention eliminates the need for a specific motor (and especially a hydraulic jack) located in the lower part of the cutting tool to unfold the slotted teeth. Therefore, the energy consumption required for the displacement of the slotted teeth is reduced, and the weight and volume of the cutting tool are also reduced. Furthermore, this invention eliminates the problems associated with hydraulic lines or power cables that must be used to supply power to the motor located in the lower part of the cutting tool in the system, as is the case with existing technologies.

[0049] The cutting tool according to the invention also has the following advantages: compared with the prior art system employing pinions, racks, cranks, and levers, it comprises fewer components and a simplified mechanism. This allows for a reduction in the risk of wear or breakage that could impair the proper unfolding of the slotted teeth. Furthermore, the grooving device according to the invention requires minimal maintenance, and its risk of jamming is particularly low.

[0050] This invention proposes a system for easily unfolding slotted teeth.

[0051] Thanks to this invention, during drilling and descent, the cutting tool can be positioned in a first configuration such that the slotted teeth are held in the retracted position. Subsequently, the guide tube and the slotted teeth will not interfere with drilling. When drilling is complete, the cutting tool can be positioned in a second configuration, which brings the slotted teeth to the unfolded position and brings the injection hole out of the hollow core.

[0052] The second configuration is called the injection configuration because it allows fluid (specifically, concrete) to be injected into the borehole.

[0053] During the lifting of the cutting tool, the slotted teeth form grooves in the inner surface of the borehole. Fluid (specifically, concrete) can be immediately injected into the grooves through the injection port of the conduit. This allows for the formation of threaded piles under optimal conditions.

[0054] Preferably, but not exhaustively, the groove has at least one straight groove portion parallel to the longitudinal direction of the hollow core. One advantage is that the position of the guide tube relative to the hollow core can be adjusted when the cutting tool is in the second configuration, without changing the position of the slotted teeth. When the tube is extended beyond the position reached when the cutting tool is in the second configuration, the engagement portion of the slotting device slides in the straight groove portion. The straight groove portion advantageously extends in the continuation of the inclined portion of the groove and extends above the inclined portion of the groove.

[0055] Preferably, the slotted teeth are movably mounted in a direction transverse to the longitudinal direction of the hollow core. The slotted teeth are advantageously movably mounted relative to the helical thread or the hollow core.

[0056] Preferably, the unfolding direction is transverse to a vertical plane passing through the longitudinal direction of the hollow core. Preferably, the unfolding direction extends in a plane that passes through the side wall of the lower tube portion of the conduit where the groove is arranged.

[0057] The grooving device advantageously includes a housing, inside which grooving teeth are movably mounted. Preferably, the housing is located at the lower end of the hollow core. The housing can be mounted on the hollow core or a helical thread. In the retracted position, the grooving teeth extend at least partially inside the housing. In the extended position, the grooving teeth protrude outside the housing. Preferably, the grooving teeth extend in the extension direction.

[0058] Advantageously, the unfolding direction of the slotted teeth is inclined relative to a plane perpendicular to the longitudinal direction of the hollow core. One advantage is that the slotted teeth are not positioned perpendicular to the inner surface of the bore when unfolded. Given this pitch angle inclined relative to the inner surface of the bore, the slotted teeth penetrate the inner surface of the bore more easily, and groove formation is facilitated. The slotted teeth are advantageously inclined downwards.

[0059] The plane perpendicular to the longitudinal direction of the hollow core is advantageously horizontal. The slotted teeth are advantageously inclined relative to the horizontal direction.

[0060] Advantageously, the engagement portion of the grooving device extends perpendicular to the grooving teeth. Preferably, the engagement portion extends perpendicular to the unfolding direction of the teeth. The engagement portion advantageously extends perpendicular to the grooved sidewall of the lower portion of the conduit.

[0061] Preferably, the joint mates with the center of the slotted teeth.

[0062] Preferably, the catheter has a distal end, and the injection port is located between the distal end and the groove. Thus, the injection port advantageously extends below the groove.

[0063] One advantage is the reduction in the unfolding distance of the conduit relative to the hollow core required to bring the injection port out to the outside of the hollow core. This results in a reduction in the groove length that allows the slotted teeth to be brought from the retracted position to the unfolded position during conduit unfolding.

[0064] Preferably, the lower portion of the conduit has a polygonal (preferably square or rectangular) cross-section, and the sidewalls of the lower portion have multiple sides, with the groove arranged in one of these sides. By matching the shape of the hollow core, this configuration allows for prevention of rotation of the conduit about the longitudinal direction of the hollow core. One advantage is improved guidance for the sliding of the grooved device's engagement portion within the conduit's groove. In this configuration, the sidewalls of the lower portion of the conduit have four sides. The groove then extends substantially in a vertical plane passing through the sidewalls of the lower portion of the conduit.

[0065] Alternatively, and without departing from the framework of the invention, the lower portion of the conduit may have a circular cross-section. In this case, its sidewalls have only one side.

[0066] Preferably, the slotted teeth extend substantially parallel to the side surface on which the groove is arranged.

[0067] More preferably, the slotted teeth are configured to abut against the sidewall of the lower portion of the conduit where the grooves are arranged. The conduit then allows the slotted teeth to unfold. Even more preferably, the slotted teeth have side surfaces configured to contact the sidewall of the lower portion of the conduit where the grooves are arranged. More preferably, during the transition from the retracted position to the unfolded position, the slotted teeth slide on the sidewall of the lower portion of the conduit.

[0068] The grooved teeth are advantageously arranged parallel to the side of the lower tube of the conduit where the groove is located.

[0069] Advantageously, the joint of the grooving device extends substantially perpendicular to the side wall of the lower portion of the conduit where the groove is arranged. One advantage is improved fit between the joint and the groove, thereby facilitating sliding of the joint within the groove. Preferably, the joint of the grooving device extends perpendicular to the side wall where the groove is arranged.

[0070] Advantageously, the sidewall of the lower tube portion of the conduit with the groove has a first side edge and a second side edge opposite to the first side edge, and the groove has at least a first groove portion extending from the first side edge to the second side edge, and the engagement portion slides in the first groove portion when the cutting tool is brought from the first configuration to the second configuration.

[0071] In other words, the first groove has a first end (preferably the lower end) and a second end (preferably the upper end), the first end being located on the first side edge of the side of the lower tube portion of the conduit, and the second end being located on the second side edge of the side.

[0072] Therefore, the first groove is inclined relative to the longitudinal direction of the hollow core. During the sliding of the engagement portion in the first groove, depending on the displacement direction of the conduit, the engagement portion displaces from the first side edge to the second side edge, and vice versa. This causes the slotted teeth to be laterally displaced between the first and second side edges. The first groove is preferably curved.

[0073] In a non-limiting manner, during the transition from the first configuration to the second configuration, the engagement portion may also slide in another recess (e.g., a longitudinal recess located below the first recess).

[0074] Preferably, when the cutting tool is moved from the first configuration to the second configuration, the joint is displaced from the first side edge of the lower tube portion of the conduit to the second side edge.

[0075] Preferably, the slotted teeth move away from the first side edge of the lower tube portion of the conduit during their unfolding.

[0076] The first and second side edges are advantageously vertical.

[0077] Preferably, the first groove portion forms a curvature that extends from a first side edge of the side on which the groove is arranged to a second side edge. One advantage is reduced friction between the joint and the conduit during translational displacement of the conduit. This allows for improved guidance of the joint and facilitates the unfolding of the slotted teeth.

[0078] Advantageously, the cutting tool is also configured to present a third configuration in which the distance between the injection hole and the lower end of the hollow core is greater than the distance in the second configuration. The cutting tool is configured to switch from the second configuration to the third configuration by a relative translational displacement of the conduit relative to the hollow core in the longitudinal direction. The joint of the grooving device is configured to slide inside the groove of the conduit, thereby displacing the grooving teeth between an unfolded position and a retracted position when the cutting tool is brought from the second configuration to the third configuration.

[0079] When the cutting tool is in the third configuration, the distance between the injection hole and the lower end of the hollow core is greater than the distance when the cutting tool is in the second configuration.

[0080] In the third configuration, the conduit extends further than in the second configuration. The conduit extends beyond the position reached in the second configuration. In the third configuration, a larger portion of the conduit extends beyond the hollow core.

[0081] According to a first non-limiting variation, the switching of the cutting tool from the second configuration to the third configuration is achieved by displacing the conduit downwards within the hollow core in the longitudinal direction. Alternatively, according to a second non-limiting variation, the switching of the cutting tool from the second configuration to the third configuration is achieved by displacing the hollow core upwards relative to the conduit in the longitudinal direction. According to yet another alternative, the switching of the cutting tool from the second configuration to the third configuration is achieved by displacing the conduit and the hollow core together relative to each other.

[0082] It should be understood that the shape of the groove allows the slotted teeth to retract when the cutting tool switches from the second configuration to the third configuration.

[0083] Therefore, the slotted teeth can be retracted by further expanding the conduit relative to the hollow core. Compared to the second configuration, the advantage of this third configuration is that it allows the slotted teeth to retract even if the conduit is blocked, thus preventing stowing by further "getting it out".

[0084] During the transition from the second position to the third position, the distal end of the conduit moves away from the lower end of the hollow core.

[0085] Advantageously, the groove also has a second groove portion that extends from a second side edge of the side wall of the lower tube portion of the conduit where the groove is arranged to a first side edge, and the engagement portion slides in the second groove portion when the cutting tool is brought from the second configuration to the third configuration.

[0086] In other words, the second groove portion has a first end (preferably the lower end) and a second end (preferably the upper end), the first end being located on the second side edge, and the second end being located on the first side edge of the side of the lower tube portion of the conduit where the groove is arranged.

[0087] Therefore, the second groove is inclined relative to the longitudinal direction of the hollow core. The inclination of the second groove is advantageously opposite to that of the first groove. During the sliding of the engagement portion in the second groove, depending on the displacement direction of the conduit, the engagement portion displaces from the second side edge of the conduit to the first side edge, and vice versa. This results in the displacement of the slotted teeth.

[0088] Preferably, when the cutting tool is moved from the second configuration to the third configuration, the joint of the grooving device is displaced from the second side edge of the lower tube portion of the conduit to the first side edge.

[0089] Preferably, during the switch from the second configuration to the third configuration, the slotted teeth are brought closer to the first side edge of the side of the conduit.

[0090] The second groove is preferably curved. Advantageously, the second groove has a curvature similar to that of the first groove. Preferably, the length of the second groove is substantially equal to the length of the first groove.

[0091] Preferably, the second groove is symmetrical to the first groove with respect to a plane of symmetry perpendicular to the longitudinal direction of the hollow core. This plane of symmetry is advantageously horizontal.

[0092] Advantageously, the first groove is located between the second groove and the distal end of the conduit. Preferably, the second groove is arranged above the first groove.

[0093] In a non-limiting manner, the groove may include a rectangular groove portion connecting the first groove portion and the second groove portion. The rectangular groove portion advantageously extends along the longitudinal direction.

[0094] Preferably, the cutting tool is further configured to present an intermediate configuration between the first and second configurations, in which the conduit is positioned such that the injection hole extends to the outside of the hollow core while the slotted teeth are held in the retracted position.

[0095] The cutting tool is moved from a first configuration to an intermediate configuration by the relative displacement of the conduit relative to the hollow core along the longitudinal direction. It should be understood that during the switch from the first configuration to the intermediate configuration, the conduit undergoes a relative translational movement relative to the hollow core, causing the injection port to be brought outside the hollow core. However, the slotted teeth are not unfolded. During the switch from the first configuration to the intermediate configuration, the engagement portion of the slotting device slides within the groove, but does not cause the slotted teeth to unfold.

[0096] One advantage is that a groove is formed only at its reduced height on the inner surface of the borehole. Another advantage is that fluid can be injected into the borehole via the injection hole even if the soil properties do not allow for the development of the slotted teeth (e.g., in cases where the soil is too hard).

[0097] The cutting tool is moved from the intermediate configuration to the second configuration by the relative displacement of the conduit relative to the hollow core along the longitudinal direction.

[0098] Advantageously, the groove has a longitudinal groove portion that extends parallel to the longitudinal direction, and the engagement portion of the grooving device slides in the longitudinal groove portion when the cutting tool is brought from the first configuration to the intermediate configuration.

[0099] Preferably, during switching from the first configuration to the intermediate configuration, the engagement portion slides in the longitudinal groove, and during switching from the intermediate configuration to the second configuration, the engagement portion slides in the first groove. Preferably, the longitudinal groove extends below the first groove. The longitudinal groove extends preferably between the first groove and the injection port. Advantageously, the longitudinal groove extends along the first side edge of the side of the lower tube portion of the conduit where the groove is arranged.

[0100] Advantageously, the grooving device is mounted on the helical thread. Preferably, the grooving device is mounted in the lower end of the helical thread.

[0101] The present invention also relates to a machine intended for constructing threaded piles in soil, the machine comprising a cutting tool as described above and a fluid (e.g., concrete) supply source connected to a conduit.

[0102] The present invention also relates to a method for constructing threaded piles in soil, the method comprising the following steps: Provide the cutting tools as described above; Connect the conduit to a fluid (e.g., concrete) supply source; A drilling hole is formed in the soil by rotating the helical thread using a cutting tool, the cutting tool being positioned in a first configuration such that the injection hole extends inside the hollow core and the slotted teeth are held in the retracted position during drilling. The cutting tool is moved from the first configuration to the second configuration by the relative translational displacement of the guide tube relative to the hollow core along the longitudinal direction of the hollow core, thereby causing the joint of the grooving device to slide inside the groove of the guide tube, displacing the grooving teeth to the unfolded position; and The cutting tool is pulled out of the borehole by a helical motion around the longitudinal direction, so that the slotted teeth form a groove in the inner surface of the borehole, while fluid is injected into the borehole from the injection hole through a conduit.

[0103] The injected fluid is preferably concrete or cement slurry.

[0104] Once the cutting tool leaves the borehole, it can be moved to the first configuration to bring the slotted teeth to the retracted position. Attached Figure Description

[0105] The invention will be better understood after reading the following description of embodiments of the invention given by way of non-limiting examples and referring to the accompanying drawings, in which: [ Figure 1 ] Figure 1 A machine intended for constructing threaded piles is shown, the machine including a first embodiment of a cutting tool according to the invention; [ Figure 2 ] Figure 2 Show Figure 1 The lower part of the conduit for the cutting tool; [ Figure 3 ] Figure 3 Show Figure 2 The cutting tool, the hollow core has been concealed; [ Figure 4 ] Figure 4 for Figure 2 Top view of the cutting tool; [ Figure 5 ] Figure 5 The diagram illustrates the formation of a drill hole using a cutting tool according to the invention, the cutting tool being placed in a first configuration referred to as a drilling configuration; [ Figure 6 ] Figure 6 For being in Figure 5 A side view of the cutting tool in the first configuration, the hollow core has been hidden; [ Figure 7 ] Figure 7 The illustration shows the formation of a groove using a cutting tool according to the invention, the cutting tool being placed in a second configuration referred to as the injection configuration; [ Figure 8 ] Figure 8 For being in Figure 7 A side view of the cutting tool in the second configuration, where the hollow core has been hidden; [ Figure 9 ] Figure 9 A threaded pile constructed in soil using a cutting tool according to the invention is shown; [ Figure 10 ] Figure 10 A second embodiment of the cutting tool according to the invention is shown, placed in the first configuration; [ Figure 11 ] Figure 11 Showing the second configuration Figure 10 Cutting tools; [ Figure 12 ] Figure 12 Showing the third configuration Figure 10 Cutting tools; [ Figure 13 ] Figure 13 A third embodiment of the cutting tool according to the invention is shown, placed in a first configuration; [ Figure 14 ] Figure 14 Showing the middle configuration Figure 13 Cutting tools; and [ Figure 15 ] Figure 15 A fourth embodiment of the cutting tool according to the invention, placed in a first configuration, is shown. Detailed Implementation

[0106] This invention relates to a cutting tool for constructing threaded piles and a machine including such a cutting tool. The invention also relates to a method for constructing threaded piles in soil using the cutting tool according to the invention.

[0107] Reference Figures 1 to 9 A first non-limiting embodiment of a cutting tool according to the invention and a machine including such a cutting tool is described.

[0108] Figure 1 A machine 10 designed for constructing threaded piles in soil is shown, comprising a first embodiment of a cutting tool 20 according to the invention. The machine 10 includes a carrier 12 and a vertical guide mast 14. The machine also includes a carriage 16 carrying a head 18 for rotating the cutting tool 20. The carriage 16 is configured to translate along the mast. Therefore, the rotational speed of the cutting tool 20 can be monitored using the rotating head 18, and the linear displacement speed of the cutting tool 20 can be monitored by monitoring the displacement of the carriage 16.

[0109] The cutting tool 20 can be configured in a first configuration and a second configuration, which will be described below.

[0110] The cutting tool 20 includes a cylindrical hollow core 22 having a lower end 22a and an upper end 22b. The hollow core has the shape of a hollow tube. The upper end 22b of the hollow core 22 mates with a rotating head 18. The hollow core 22 extends in a longitudinal direction L, which is generally vertical. The hollow core has an outer surface 23 on which a helical thread 24 is mounted. The helical thread 24 has a pitch. The helical thread extends along the hollow core 22 from the upper end 22b to the lower end 22a. The helical thread 24 has an outer peripheral edge 26 that defines a cylindrical volume V, such as... Figure 5 As shown.

[0111] refer to Figure 6 The figure shows the cutting tool in a side view, with the hollow core obscured for better observation. It can be seen that the cutting tool 20 also includes a conduit 30, which is translatably mounted inside the hollow core 22 along the longitudinal direction L. The conduit 30 and the hollow core 22 are configured to allow for relative translational movement along the longitudinal direction L.

[0112] exist Figure 1 As can be seen in this non-limiting example, the cutting tool 20 includes jacks 29 disposed between the rotating head 18 and the platform connected to the conduit 30. These jacks 29 allow the conduit 30 to translate relative to the hollow core 22 along the longitudinal direction L of the hollow core.

[0113] The conduit 30 also extends along the longitudinal direction of the hollow core 22. The hollow core 22 includes... Figure 4 The visible part is an inner housing 27 with a square cross-section, within which a conduit extends. The conduit 30 has a distal end 30a and a proximal end 30b. The proximal end 30b is configured to... Figure 1 The visible supply conduit Ca is connected to the concrete supply source. The conduit 30 is hollow and defines an internal conduit C, which allows concrete to be transported from its proximal end 30b to its distal end 30a.

[0114] In this non-restrictive example, and as Figure 5 As shown, the conduit includes a lower tube section 31 and an upper tube section 33. The upper tube section 33 has a circular cross-section.

[0115] refer to Figure 3 The figure shows the lower tube portion 31 of the conduit 30, with the hollow core concealed for better viewing. An injection port 35 can be seen disposed within the lower tube portion 31, near the distal end 30a of the conduit. The injection port 35 leads into the internal conduit C and allows concrete to be injected toward the inner surface of the borehole. The conduit 30 (and more specifically the lower tube portion 31) is also equipped with a cutting tip 32 that closes the distal end 30a of the conduit. The cutting tip 32 is equipped with cutting teeth.

[0116] The lower portion 31 of the catheter 30 has a sidewall 34. For example... Figure 4 As shown in the top cross-sectional view, in this non-limiting example, the lower tube portion 31 of the conduit 30 has a square cross-section. Therefore, the sidewall 34 of the lower tube portion 31 has a first side 36, a second side 37, a third side 38, and a fourth side 39. An injection port is arranged in the second side 37. The first side 36 of the sidewall 34 of the lower tube portion 31 has a first side edge 36a and a second side edge 36b opposite to the first side edge. These side edges 36a and 36b extend vertically.

[0117] like Figure 6 As shown, a groove 40 is disposed in the first side surface 36 of the side wall 34 of the lower tube portion 31 of the conduit 30. The groove 40 has a depth of several centimeters. The groove 40 extends in a generally direction parallel to the longitudinal direction L of the hollow core portion 22. The groove 40 has a lower end 40a located on a first side edge 36a of the first side surface 36. The groove has an upper end 40b located on a second side edge 36b.

[0118] In this non-limiting embodiment, the groove 40 includes a first groove portion 42 that is inclined relative to the longitudinal direction L of the hollow core 22. The groove also includes a straight groove portion 43 that extends in a continuation of the first groove portion 42. The straight groove portion 43 extends parallel to the longitudinal direction L of the hollow core 22 along the second side edge 36b of the first side surface 36 of the sidewall 34 of the conduit 30. The straight groove portion 43 extends above the first groove portion 42. The first groove portion 42 is curved and convex. The groove 40 (and more specifically the first groove portion 42) extends from the first side edge 36a of the side surface 34 of the conduit to the second side edge 36b of the side surface. Therefore, the groove is partially inclined relative to the longitudinal direction L of the core and relative to the vertical direction.

[0119] like Figure 3 As shown, where the hollow core 22 is hidden for clarity, the cutting tool 20 also includes a grooving device 50. The grooving device 50 includes grooving teeth 52. The grooving teeth 52 extend in the main direction and have a tip 52a configured to contact the inner surface of a drilled hole to form a groove therein. A through-hole 54 is arranged in the grooving teeth. The through-hole 54 is perpendicular to the main direction of the grooving teeth. The grooving teeth 52 also include an inner surface 56 and an outer surface 58 opposite to the inner surface 56.

[0120] The grooving device 50 also includes a lug-shaped engagement portion 60, the length of which is greater than the length of the through hole 54 of the grooving tooth 52. The engagement portion 60 is fixed to the grooving tooth 50 and extends perpendicular to the grooving tooth. More specifically, the engagement portion 60 extends perpendicular to the inner surface 56 and outer surface 58 of the grooving tooth 52. The engagement portion 60 has an end portion 60a protruding from the inner surface 56 of the grooving tooth 52.

[0121] like Figure 2 As shown in the figure, the lower part of the cutting tool 20 according to the invention is shown, with slotted teeth 52 mounted on the hollow core 22 via a housing 62 and on a helical thread. A first side 36 with grooves 40 extends from the slotted teeth toward the sidewall 34 of the conduit. The inner side 56 of the slotted teeth abuts against the first side 36 of the sidewall of the conduit 30.

[0122] The slotted teeth 52 are movably mounted inside the housing 62 along the unfolding direction X. The unfolding direction X is inclined relative to a plane perpendicular to the longitudinal direction L of the hollow core 22, and therefore inclined relative to the horizontal direction. The unfolding direction X is parallel to the first side surface 36 of the sidewall 34 of the conduit. The housing 62 extends in a continuation of the helical thread 24. The housing 62 forms a shell for the slotted teeth. A vertical plane passing through the unfolding direction is parallel to the first side surface 36 of the sidewall 34 of the conduit 30.

[0123] The slotted tooth 52 can be in a retracted position, such as Figures 2 to 6 As shown, in the retracted position, the slotted teeth 52 extend within the cylindrical volume V defined by the outer peripheral edge 26 of the helical thread 24. This is illustrated in the side view of the cutting tool. Figure 5 This is especially evident in the center. The slotted teeth 52 can also be positioned in an expanded manner, such as... Figure 7 and Figure 8 As shown, in the unfolded position, the slotted teeth 52 protrude outside the cylindrical volume V.

[0124] The end 60a of the joint 60 of the slotting device is configured to engage in the groove 40, and slides inside the groove when the guide tube 30 is translated along the longitudinal direction L of the hollow core 22.

[0125] Now refer to Figures 5 to 8 The steps of a method for constructing threaded piles in soil S according to the present invention are described.

[0126] The cutting tool is initially placed in the first configuration, such as Figure 5 and Figure 6 As shown. In this first configuration, the conduit 30 is housed and extends substantially inside the hollow core 22, such that the injection port 35 also extends inside the hollow core 22. The cutting tip 32 further closes the hollow core. The engagement portion 60 of the grooving device then engages in the first recess portion 42 of the groove 40 and extends near the first side edge 36a of the first side surface 36 of the sidewall 34 of the lower tube portion 31 of the conduit 30. When the cutting tool is in this first configuration, the grooving teeth 52 are in a retracted position and therefore do not protrude from the cylindrical volume V.

[0127] like Figure 5 As shown, a borehole is formed by pivoting a cutting tool 20 (and specifically, a helical thread 24) placed in this first configuration about the longitudinal direction L of the hollow core, using a rotating head 18. The cutting tool is driven into the soil S. During the descent of the cutting tool 20, the helical thread 24 allows cutting of the soil S to form a borehole. During borehole formation, the slotted teeth 52 do not contact the soil, thus preventing instability of the surrounding soil.

[0128] When drilling is complete, the cutting tool is moved to the second configuration by the longitudinal translational displacement of the guide tube 30 relative to the hollow core 22. In other words, the switch from the first configuration to the second configuration is achieved by unfolding the guide tube. This is done by... Figure 5 and Figure 6 Switch to Figure 7 and Figure 8 To illustrate. During this relative displacement of the conduit relative to the hollow core, the distal end 30a of the conduit 30 remains in contact with the bottom of the borehole. In this non-limiting example, a jack 29 is used to displace the conduit 30. Figure 7 and Figure 8 As shown, in the second configuration, the conduit 30 protrudes from the lower end portion 22a of the hollow core 22, thus extending the injection port 35 beyond the hollow core. The distal end portion 30a of the conduit moves away from the lower end portion 22a of the hollow core.

[0129] When the cutting tool 20 switches from the first configuration to the second configuration, the relative translational displacement of the guide tube 30 relative to the hollow core 22 causes the engagement portion 60 of the grooving device 50 to slide within the first groove portion 42 of the groove 40. Given the inclination and curvature of this first groove portion 42, the engagement portion 60 is brought closer to the second side edge 36b of the first side surface 36 of the sidewall 34 of the lower tube portion 31 of the guide tube 30. Therefore, the grooving teeth 52 are translated along the unfolding direction X. During tube unfolding, and therefore when the cutting tool switches from the first configuration to the second configuration, the grooving teeth are brought from the retracted position to the unfolded position. Thus, the unfolding of the grooving teeth 52 is achieved and thus facilitated by the relative displacement of the guide tube 30 relative to the hollow core. In the unfolded position, the grooving teeth 52 protrude beyond the cylindrical volume V, causing them to contact the inner surface of the borehole, such as... Figure 7 and Figure 8 As shown.

[0130] In a non-limiting manner, although not shown, the conduit can be further extended beyond the hollow core 22. This allows the engagement portion 60 of the slotting device to slide within the straight groove portion 43 of the groove 40. The engagement portion 60 then translates along the longitudinal direction L of the hollow core without changing the position of the slotting teeth 52.

[0131] like Figure 7 As shown, the cutting tool 20 in the second configuration can be lifted while pivoting about the longitudinal direction L, causing the slotted teeth 52 to form a groove R in the inner surface of the borehole. Simultaneously, during the lifting of the cutting tool, concrete is injected into the borehole from the injection hole 35. The concrete is injected toward the groove previously formed by the slotted teeth 52.

[0132] The cutting tool 20 is then pulled out of the borehole, thereby forming a threaded pile P in the soil, as shown. Figure 9 As shown. The pile P has a thread F. The cutting tool 20 can then be brought back to the first configuration by displacing the guide tube 30 toward the interior of the hollow core to accommodate it. As a result, the slotted teeth 52 are brought from the unfolded position to the retracted position.

[0133] Figure 10 , Figure 11 and Figure 12A second embodiment of the cutting tool 20 according to the invention is shown. In this embodiment, the groove 40 further includes a second groove portion 44. The second groove portion 44 is curved and inclined relative to the longitudinal direction L of the hollow core. The second groove portion 44 forms a curvature similar to that of the first groove portion 42. The length of the second groove portion 44 is substantially equal to the length of the first groove portion 42. As in the first embodiment, the groove 40 also includes a straight groove portion 43, which connects the first groove portion 42 and the second groove portion 44. When considered with respect to a plane perpendicular to the longitudinal direction L of the hollow core 22, the second groove portion 44 and the first groove portion 42 are symmetrical about each other.

[0134] and Figures 1 to 8 Similar to the first embodiment, in this second embodiment, when the cutting tool is brought from the first configuration to the second configuration via the relative displacement of the conduit 30 relative to the hollow core 22, the slotted teeth 52 are brought from the retracted position to the extended position, taking into account the sliding of the engagement portion 60 in the first groove portion 42. Figure 10 Switch to Figure 11 This illustrates the switch from the first configuration to the second configuration (causing the slotted teeth 52 to unfold). Figure 11 In the image, it can be seen that the conduit 30 has been unfolded, causing the joint 60 of the slotting device to shift beyond the first groove 42 until it extends into the straight groove 43.

[0135] In this second embodiment, the relative translational displacement of the conduit 30 relative to the hollow core 22 exceeds [a certain value]. Figure 11 As shown, the cutting tool 20 can be further moved to the third configuration. During the switch from the second configuration to the third configuration, the distal end 30a of the conduit 30 and the injection port 35 are further moved away from the lower end 22a of the hollow core.

[0136] exist Figure 12 In the third configuration shown, the distance between the injection hole 35 and the lower end portion 22a of the hollow core is greater than that in the second configuration. The conduit is extended to a greater extent than in the second configuration. During the transition from the second to the third configuration, the engagement portion 60 of the slotting device 50 slides in the second recess portion 44, which is inclined. Due to the inclination of the second recess portion 44, the engagement portion 60 is brought closer to the first side edge 36a of the first side surface 36 of the sidewall 34 of the lower tube portion 31 of the conduit 30. Therefore, the slotting teeth 52 are translated along the unfolding direction X. When the cutting tool 20 is brought from the second configuration to the third configuration, and therefore when the conduit 30 is further unfolded, the slotting teeth are brought from the unfolded position to the retracted position. One advantage is that the slotting teeth 52 can be brought to the retracted position even if the conduit 30 cannot be accommodated, and even if the cutting tool 20 cannot be brought from the second configuration to the first configuration.

[0137] By from Figure 11 Switch to Figure 12 This illustrates the relative translational displacement of the conduit 30 relative to the hollow core 22 during the transition from the second configuration to the third configuration, which causes the slotted teeth 52 to switch from an extended position to a retracted position.

[0138] Figure 13 and Figure 14 A third embodiment of the cutting tool 20 according to the present invention is shown. Figure 13 This is a side view of this variant of the cutting tool 20, with the hollow core 22 hidden for clearer observation.

[0139] In this embodiment, the groove 40 further includes a longitudinal groove portion 46 disposed below the first groove portion 42, located between the first groove portion and the injection hole 35. The first groove portion 42 extends in a continuation of the longitudinal groove portion 46. The longitudinal groove portion 46 extends parallel to the longitudinal direction L along the first side edge 36a of the first side surface 36 of the sidewall 34 of the lower tube portion 31 of the conduit 30. Figure 13 In this configuration, the cutting tool is set in the first configuration.

[0140] In this third embodiment, the cutting tool 20 can also be placed in an intermediate configuration between the first and second configurations. This intermediate configuration is... Figure 14 As shown in the diagram, the switching from the first configuration to the intermediate configuration is achieved by a relative translational displacement of the conduit 30 relative to the hollow core 22 in the longitudinal direction. This displacement causes the conduit 30 to be withdrawn from the hollow core 22. Consequently, the engagement portion 60 of the slotting device 50 slides within the longitudinal groove portion 46 of the groove 40. Since the longitudinal groove portion 46 extends parallel to the longitudinal direction, the engagement portion 60 is displaced along this longitudinal direction L and maintains a constant distance from the first side edge 36a and the second side edge 36b of the first side surface 36 of the sidewall 34 of the lower tube portion 31 of the conduit 30. Therefore, during this deployment of the conduit 30, and thus when the cutting tool switches from the first configuration to the intermediate configuration, the slotting teeth 52 do not displace laterally and are held in the retracted position.

[0141] In the intermediate configuration, when the slotted teeth 52 are retracted, the injection hole 35 extends to the outside of the hollow core 22. Therefore, fluid injection can be performed even if it is not desired or impossible to unfold the slotted teeth (e.g., if the soil properties do not permit it).

[0142] The switching from the intermediate configuration to the second configuration is also achieved by displacing the conduit 30 relative to the hollow core 22 beyond the intermediate configuration. The engaging portion 60 of the slotting device 50 then slides in the first groove portion 42, which brings the slotting teeth 52 from the retracted position to the unfolded position, as in the above embodiment.

[0143] Figure 15 A fourth embodiment of the cutting tool 20 according to the present invention is shown. Figure 15 This is a side view of this variant of the cutting tool 20; the hollow core 22 has been hidden for clearer observation. In this variant, with... Figures 10 to 12 Similar to the second embodiment, the groove 40 includes a second inclined groove portion 44 that allows the cutting tool to be brought to a third configuration in which the slotted teeth 52 are retracted and the guide tube 30 is extended to a greater extent than in the second configuration. Furthermore, as... Figure 13 and Figure 14 As shown in the embodiment, the groove 40 also includes a longitudinal groove 46, which allows the cutting tool to be placed in an intermediate configuration.

Claims

1. A cutting tool (20) for building a threaded pile (P) in soil (S), the cutting tool comprising: - a cylindrical hollow core (22) having a lower end (22a) and extending along a longitudinal direction (L); - at least one helical thread (24) mounted on an outer surface (23) of the hollow core and having an outer peripheral edge (26); - a duct (30) configured to be connected to a fluid supply, the fluid being for example concrete, and translatablely mounted inside the hollow core along the longitudinal direction, the duct comprising at least a lower duct portion (31) having a lateral wall (34) in which a groove is formed at least partially inclined with respect to the longitudinal direction, an injection hole (35) being also arranged in the lateral wall of the lower duct portion; and - a slotting device (50) comprising a slotting tooth (52) translatable between a retracted position, in which the slotting tooth extends inside a cylindrical volume (V) defined by the outer peripheral edge of the helical thread, and a deployed position, in which the slotting tooth projects outside the cylindrical volume, the slotting device further comprising an engagement portion (60) fixed to the slotting tooth, the cutting tool being configured to assume at least a first configuration, called drilling configuration, in which the duct is positioned so that the injection hole extends inside the hollow core, and a second configuration, called injection configuration, in which the duct projects from the lower end of the hollow core so that the injection hole extends outside the hollow core, the cutting tool being configured to switch from the first configuration to the second configuration by a relative translational displacement of the duct with respect to the hollow core along the longitudinal direction, the engagement portion of the slotting device being configured to slide inside the groove of the duct, whereby the slotting tooth is displaced between the retracted position and the deployed position when the cutting tool is brought from the first configuration to the second configuration.

2. The cutting tool according to claim 1, wherein the slotting tooth (52) is translatablely mounted along a deployment direction (X) transverse to the longitudinal direction (L) of the hollow core (22).

3. The cutting tool according to claim 2, wherein the deployment direction (X) of the slotting tooth (52) is inclined with respect to a plane perpendicular to the longitudinal direction (L) of the hollow core (22).

4. The cutting tool according to any one of claims 1 to 3, wherein the engagement portion (60) of the slotting device (50) extends perpendicularly to the slotting tooth (52).

5. The cutting tool according to any one of claims 1 to 4, wherein the duct (30) has a distal end (30a), the injection hole (35) being located between the distal end and the groove (40).

6. The cutting tool according to any one of claims 1 to 5, wherein the lower tube portion of the duct (30) has a polygonal cross-section, preferably a square or rectangular cross-section, the side wall (34) of the lower tube portion (31) of the duct having a plurality of sides (36, 37, 38, 39), the groove (40) being arranged in one side (36) of the plurality of sides.

7. The cutting tool according to claim 6, wherein the slotted tooth (52) extends substantially parallel to the side (36) of the side wall (34) of the lower tube portion (31) of the duct (30) in which the groove (40) is arranged.

8. The cutting tool according to claim 6 or 7, wherein the engagement portion (60) of the slotting device (50) extends substantially perpendicular to the side (36) of the side wall (34) of the lower tube portion (31) of the duct (30) in which the groove (40) is arranged.

9. The cutting tool according to any one of claims 6 to 8, wherein the side (36) of the side wall (34) of the lower tube portion (31) of the duct (30) in which the groove (40) is arranged has a first side edge (36a) and a second side edge (36b) opposite the first side edge, and wherein the groove has at least a first groove portion (42) extending from the first side edge to the second side edge, the engagement portion (60) sliding in the first groove portion when the cutting tool is brought from the first configuration to the second configuration.

10. The cutting tool according to claim 9, wherein the first groove portion (42) forms a curvature extending from the first side edge (36a) to the second side edge (36b) of the side (36) in which the groove (40) is arranged.

11. The cutting tool according to any one of claims 1 to 10, wherein the cutting tool (20) is further configured to assume a third configuration in which the distance between the injection hole (35) and the lower end (22a) of the hollow core (22) is greater than in the second configuration, the cutting tool being configured to switch from the second configuration to the third configuration by a relative translational displacement of the duct with respect to the hollow core in the longitudinal direction, the engagement portion (60) of the slotting device (50) being configured to slide inside the groove (40) of the duct, whereby the slotted tooth (52) is displaced between the deployed position and the retracted position when the cutting tool is brought from the second configuration to the third configuration.

12. The cutting tool according to claim 11 in conjunction with claim 9 or 10, wherein the groove (40) further has a second groove portion (44) extending from the second side edge (36b) of the side surface (36) on which the groove is arranged on the lower tube portion (31) of the conduit (30) to the first side edge (36a), wherein the engagement portion (60) slides in the second groove portion when the cutting tool is brought from the second configuration to the third configuration.

13. The cutting tool according to any one of claims 1 to 12, wherein the cutting tool (20) is further configured to present an intermediate configuration between the first configuration and the second configuration, wherein the conduit (30) is positioned such that the injection hole (35) extends outside the hollow core (22) while the slotted teeth (52) are held in the retracted position.

14. The cutting tool according to claim 13, wherein the groove (40) has a longitudinal groove portion (46) extending parallel to the longitudinal direction (L), and the engagement portion (60) of the grooving device (50) slides in the longitudinal groove portion when the cutting tool is brought from the first configuration to the intermediate configuration.

15. The cutting tool according to any one of claims 1 to 14, wherein the grooving device (50) is mounted on the helical thread (24).

16. A machine (10) intended for constructing threaded piles (P) in soil (S), the machine comprising a cutting tool (20) according to any one of claims 1 to 15 and a fluid supply source connected to the conduit (30), the fluid being, for example, concrete.

17. A method for constructing threaded piles (P) in soil (S), the method comprising the steps of: A cutting tool (20) according to any one of claims 1 to 15 is provided; The conduit (30) is connected to a fluid supply source, such as concrete; Using the cutting tool to form a borehole in the soil by rotating the helical thread (24), the cutting tool is positioned in the first configuration such that the injection hole (35) extends inside the hollow core (22) and the slotted teeth (52) are held in the retracted position during drilling; The cutting tool is moved from the first configuration to the second configuration by the relative translational displacement of the conduit relative to the hollow core along the longitudinal direction of the hollow core, thereby causing the engagement portion of the grooving device to slide within the groove (40) of the conduit, so that the grooving teeth are displaced to the unfolded position; as well as The cutting tool (20) is pulled out of the borehole by a helical motion around the longitudinal direction, such that the slotted teeth form a groove (R) in the inner surface of the borehole, while the fluid is injected into the borehole from the injection hole via the conduit.

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