Method for fixing the angle position of a luffing jib crane to a luffing jib

Abstract

A method for fixing the angular position of a crane jib displaceable on lifting and lowering by means of a winch (3) integrated with a motor (30) driving a drum (31) on which a rope is wound and fixed to a pressure plate (40) provided with an arc-shaped oval locking hole (41), the method comprising: - measuring a speed parameter (PM) representative of the angular speed of the jib; - controlling the motor to displace the jib by limiting the speed parameter to a first maximum value (V1) and the motor torque to a first limit value (C1) until reaching an angular position in which a lock (42) is aligned with and then locked into the locking hole; - controlling the motor to displace the jib on lowering by limiting the speed parameter to a second maximum value (V2) and the motor torque to a second limit value (C2) until the speed parameter remains at zero for a predetermined period of time to stop the motor.

Description

Technical Field

[0001] The present invention relates to a method for fixing a pitch cantilever crane in order to fix the angular position of the pitch cantilever.

[0002] This invention relates to the field of pitch cantilever cranes equipped with a pitch winch, the pitch winch including a pitch motor driving a drum on which a pitch rope connected to the pitch cantilever is wound so as to drive the pitch cantilever with angular displacement relative to the horizontal plane. Background Technology

[0003] This invention can relate to two types of cranes: luffing jib cranes and self-erecting cranes.

[0004] A boom crane is a type of crane that includes a mast at the top of which a cantilever is pivotally mounted and can be raised and lowered. In other words, the cantilever can pivot at the horizontal of the mast so that it can be raised to a near-vertical angle and lowered to a horizontal angle. The cantilever is movable during raising and lowering by means of a pitch winch (also known as a lifting winch), which integrates a motor that drives a drum on which a pitch rope (also known as a lifting rope) connected to the cantilever is wound.

[0005] A self-elevating crane, also known as a folding crane, collapsible crane, or transportable crane, is a type of crane that includes a mast supporting a cantilever. This type of crane can be configured between a transport configuration where the mast and cantilever are folded or side-by-side, and a work configuration where the mast and cantilever are extended to perform load lifting and distribution operations. The cantilever is movable during lifting and lowering to allow it to be folded and extended using a pitch winch (also known as a holding winch), which integrates a motor driving a drum on which a pitch rope (also known as a holding rope) is wound to the cantilever.

[0006] The present invention focuses on locking the pitch cantilever at a desired angular position so as to securely and reliably hold or maintain it at that angular position, which is more or less tilted relative to the horizontal plane.

[0007] During the angular displacement phase of the pitch boom—in other words, when it is raised or lowered to change its angular position—it is known that the movement and fixation of the pitch boom are ensured by means of a motor (also known as a pitch motor) and an associated motor brake. Conversely, once the angular position is reached, it is crucial to fix it in order to make the crane configuration more reliable.

[0008] For this retention, a locking system using a pitch winch is known. This system includes, on one hand, a locking plate fixed to the drum and provided with circumferentially distributed circular locking holes, and on the other hand, a lock with a cylindrical section complementary to the locking holes. This lock is mounted on a fixed chassis or frame and is movable between the following positions:

[0009] - A locking configuration in which a lock engages in one of the locking holes to prevent rotation of the drum and thus keep the cantilever locked in the desired angular position; and

[0010] - Release configuration, in which the lock disengages from the locking hole to release the rotation of the drum and thus allow the cantilever to be raised / lowered.

[0011] However, this solution presents several challenges. Firstly, to engage the locks in the locking holes, the operator must precisely align them, which involves pulse-controlled pitch motors, a process that is inherently imprecise. Secondly, to disengage the locks from the locking holes, the force applied to the locks by the locking plate fixed to the drum is crucial, necessitating manual intervention to rotate the drum and release the force on the locks. This is both impractical and prone to human error during intervention. Summary of the Invention

[0012] The present invention aims to provide a solution that can securely and reliably maintain the angular position of a pitch cantilever, a solution involving minimal human intervention and simplifying the locking / unlocking operation of the pitch winch.

[0013] Therefore, the present invention proposes a fixing method for a pitch cantilever crane to fix the angular position of the pitch cantilever, which is movable during lifting and lowering by means of a pitch winch, the pitch winch including a pitch motor driving a drum, on which a pitch rope connected to the pitch cantilever is wound, the drum being rotatably fixed to a locking plate provided with circumferentially distributed locking holes, the fixing method implementing the following locking stage, wherein the lock is moved in the following manner:

[0014] - From the release configuration, where the lock disengages from the locking plate to authorize drum rotation and thus allow the tilting cantilever to be raised / lowered.

[0015] -To the locking configuration, wherein, after alignment, the lock engages in one of the locking holes to prevent the drum from rotating and thus fix the angular position of the pitch cantilever;

[0016] The remarkable feature of this method for fixing a pitching cantilever crane is that the locking holes are all elliptical in shape, so that the lock engages with the circumferential gap within the locking hole in the locking configuration.

[0017] Therefore, the present invention proposes to first use a locking plate with an elliptical and arc-shaped locking hole, that is, in the shape of an arc centered on the rotation axis of the drum, which allows the lock to engage in the locking hole with a circumferential clearance, which helps to lock and authorize slight rotation of the drum; the circumferential clearance depends on the length of the locking hole and the cross-section of the lock.

[0018] Advantageously, the fixing method includes the following steps:

[0019] - Measure the velocity parameter during lifting or lowering, which represents the displacement angular velocity of the pitch cantilever;

[0020] - The first control of the pitch motor is performed by limiting the speed parameter to a first maximum speed value and limiting the motor torque of the pitch motor to a first torque value limit to move the pitch cantilever during lifting or lowering until a given angular position of the pitch cantilever is reached, in which the lock aligns with one of the locking holes of the locking plate, the lock occupying the release configuration;

[0021] - The locking phase is implemented by moving the lock from the release configuration to the lock configuration;

[0022] - A second control of the pitch motor is performed by limiting the speed parameter to a second maximum speed value lower than the first maximum speed value and limiting the motor torque of the pitch motor to a second torque limit value lower than the first torque limit value to shift the pitch cantilever during descent until the speed parameter is held at zero for a predetermined time to stop the pitch motor.

[0023] Subsequently, the present invention proposes to automate the locking mechanism at least in part, wherein the first control of the pitch motor is intended to achieve the desired angular position by raising / lowering the pitch cantilever with a speed parameter limited to a first maximum speed value (which preferably corresponds to the maximum value of the mechanical authorization) and a motor torque limited to a first torque limit value; the first torque limit value is a high value that allows the pitch motor to withstand force at all angular positions of the pitch cantilever.

[0024] Then, once the lock is engaged in one of the elliptical locking holes, a second control of the pitch motor is designed to slightly lower the pitch cantilever until the lock abuts one end of the locking hole. This descent is performed at a speed parameter limited to a second maximum speed value (in other words, at low speed), suitable for the possible distance traveled (up to the length of the locking hole) and the precision required for proper maneuvering. During this second control, the motor torque itself is limited to a second torque limit value. Once the lock is engaged, the motor torque remains limited to the second torque limit value, and the pitch motor continues to be forced to this second torque limit value while the speed parameter is zero (in effect, due to the engagement of the lock, the drum no longer rotates and the cantilever no longer descends). This zero-speed phase will last for a predetermined duration (e.g., several seconds) before the pitch motor stops, and thus the pitch winch is locked.

[0025] It should also be noted that the speed parameter may correspond to the displacement angular velocity of the pitch cantilever, or to another speed or another parameter that depends on that angular velocity, such as the rotational speed of the drum, the motor speed, etc.

[0026] Based on a feature, the operator performs verification of the lock-occupying locking configuration in order to authorize secondary control of the pitch motor.

[0027] According to one variant, the shifting of the lock between the locked and released configurations is performed manually by the operator.

[0028] According to another feature, the detection system performs the detection of the lock occupying the locking configuration in order to authorize the second control of the pitch motor.

[0029] According to one variant, the shifting of the lock between the locked and released configurations is operated by an actuator.

[0030] In a particular embodiment, after the second control of the pitch motor, the release phase is implemented through the following steps:

[0031] - A third control of the pitch motor is performed by limiting the speed parameter to a second maximum speed value and limiting the motor torque of the pitch motor to a second torque limit value to shift the pitch cantilever during lifting;

[0032] - Perform a lock shift from a locked configuration to a released configuration.

[0033] In other words, to unlock the pitch winch, it is again recommended to operate at a low speed, that is, at a speed parameter limited to the second maximum speed value and at a motor torque limited to the second torque limit, and to slightly raise the pitch cantilever to remove the lock from its support at the end of the locking hole, thereby allowing the lock to easily disengage from the locking hole.

[0034] According to one possibility, before or after the shift of the lock-to-release configuration, the third control of the pitch motor is followed by the closing of the motor brake associated with the pitch motor.

[0035] Therefore, when the release phase is completed, the motor brake is closed so that the pitch cantilever is held in place by means of the motor brake before the motor brake is opened to operate the angular displacement of the pitch cantilever, such as folding the pitch cantilever or reaching a new angular position.

[0036] According to another possibility, the shifting of the lock-to-release configuration is followed by a fourth control of the pitch motor, which shifts the pitch cantilever during lifting or lowering by limiting the speed parameter to a first maximum speed and limiting the motor torque to a first torque limit.

[0037] In other words, once the pitch is unlocked by the winch, the pitch boom can be moved again at high speed, i.e., at a speed parameter limited to the first maximum speed value and with a motor torque suitable for bearing the force. Where appropriate, the motor brake is opened to enable the fourth control of the pitch motor.

[0038] Alternatively, the operator may verify the lock-on release configuration to authorize a fourth control of the pitch motor.

[0039] According to another possibility, the detection system performs the detection of the lock occupancy release configuration in order to authorize the fourth control of the pitch motor.

[0040] Advantageously, when taking into account that the locking holes extend in a given locking angle sector, the first control of the pitch motor follows the forward displacement of the lock, which results in the lock being substantially centered in the locking hole, and the second control of the pitch motor causes the drum to rotate in the descending direction along an angular descending sector that is substantially equal to half of the angular locking sector.

[0041] In a particular embodiment, a third control of the pitch motor causes the drum to rotate in the lifting direction opposite to the descent direction according to an angular tilt sector that is substantially equal to half the angle locking sector. In the context of this invention, "substantially equal to" should be understood as being exactly equal to or more or less 15% equal to the length of the locking hole.

[0042] In advantageous applications, the tilting jib crane is either a luffing jib crane or a self-erecting crane.

[0043] An advantageous application of this invention for self-elevating cranes is that, once deployed, in other words, in its working configuration, the boom remains locked and reliable.

[0044] The advantageous application of this invention for boom cranes is that it enables the boom to remain locked and reliable in any tilted configuration of the boom (in other words, regardless of its tilt).

[0045] The present invention also relates to a pitch cantilever crane, comprising a pitch cantilever that is movable during lifting and lowering by means of a pitch winch, the pitch winch integrating a pitch motor for driving a drum, on which a pitch rope connected to the pitch cantilever is wound, the drum being rotatably fixed to a locking plate having circumferentially distributed locking holes, and the locking plate further comprising a lock movable between the following positions:

[0046] - Release configuration, in which the lock disengages from the locking plate to authorize the rotation of the drum and thus allow the pitch cantilever to be raised / lowered; and

[0047] - Locking configuration, in which a lock engages within a locking hole to prevent rotation of the drum and thus fix the angular position of the pitch cantilever;

[0048] The notable feature of the pitching cantilever crane is that the locking holes are all elliptical arc-shaped, so that the lock engages with the circumferential gap within the locking hole in the locking configuration.

[0049] Advantageously, the pitch cantilever crane includes a measurement system for measuring a velocity parameter representing the displacement angular velocity of the pitch cantilever during lifting or lowering; and a monitoring / control system connected to the pitch motor and the measurement system, the monitoring / control system being configured to:

[0050] - First control of the pitch motor is performed by limiting the speed parameter to a first maximum speed value and limiting the motor torque of the pitch motor to a first torque limit value to move the pitch cantilever during lifting or lowering until a given angular position of the pitch cantilever is reached, in which the lock aligns with one of the locking holes of the locking plate, the lock occupying the release configuration;

[0051] - After the lock is moved forward to occupy the locking configuration engaged in the aligned locking hole, the second control of the pitch motor is performed by limiting the speed parameter to a second maximum speed value less than the first maximum speed value and limiting the motor torque of the pitch motor to a second torque limit value less than the first torque limit value to move the pitch cantilever during descent until the speed parameter is held at zero for a predetermined time to stop the pitch motor. Attached Figure Description

[0052] Other features and advantages of the invention will become apparent upon reading the following detailed description of non-limiting examples of embodiments with reference to the accompanying drawings, wherein:

[0053] Figure 1 This is a schematic diagram of a tilting cantilever crane of the self-elevating crane type applicable to the present invention;

[0054] Figure 2This is a partial schematic diagram of a luffing jib crane, which is also applicable to the present invention.

[0055] Figure 3 The present invention relates to a pitching winch for a pitching cantilever crane, for example... Figure 1 and Figure 2 A schematic diagram of a pitch winch shown; and

[0056] Figure 4 This is a schematic diagram of the main components required to implement the fixing method according to the present invention. Detailed Implementation

[0057] refer to Figure 1 The first pitching cantilever crane 1 according to the invention is a self-erecting crane, hereinafter referred to as crane 1, which includes a mast 10 mounted on a platform 11 (e.g., a rotating platform) and supporting a cantilever 12 of the pitching cantilever type. The mast 10 may be a collapsible mast or a telescopic mast (as in the example shown), and the cantilever 12 is a collapsible cantilever that includes a series of cantilever elements hinged to each other.

[0058] The crane 1 can be configured between the following settings:

[0059] - Transport configuration in which mast 10 and cantilever 12 are folded onto themselves or placed side-by-side, essentially horizontally; and

[0060] -Work configuration (e.g.) Figure 1 As shown in the figure, the mast 10 and the cantilever 12 are deployed, the mast 10 is basically vertical and the cantilever 12 is basically horizontal.

[0061] Therefore, the crane 1 includes a folding / unfolding mechanism that acts on the mast 10 and the cantilever 12 to fold and unfold the crane 1, and thus move it from a working configuration to a transport configuration, and vice versa. The cantilever 12 is thus tilted to a certain degree, i.e., during configuration changes between the transport and working configurations, the cantilever 12 is tilted more or less to unfold or fold. The folding / unfolding mechanism therefore includes a pitch winch 3 (also referred to as a holding winch in this self-elevating crane model), which acts on a pitch rope 35 (also referred to as a holding rope in this self-elevating crane model), which is connected to the cantilever 12 via a return member such as a pulley and / or a tie rod. In the illustrated example, the pitch winch 3 of the crane 1 is mounted on the platform 11.

[0062] refer to Figure 2The second pitching cantilever crane 2 according to the invention is a boom crane, hereinafter referred to as crane 2, which includes a mast 20 mounted on a platform (not visible) and supporting a pitching cantilever 22 pivotally mounted on top of a mast 20 along a horizontal axis. Thus, in a working configuration, the cantilever 22 can be pivoted to be raised to a nearly vertical angular position and lowered to a horizontal angular position.

[0063] Depending on whether the cantilever 22 is raised or lowered to a greater or lesser extent, the crane 2 can be configured between the following different angle configurations:

[0064] - Upgraded configuration, in which cantilever 22 is raised to a maximized, almost vertical angle position; and

[0065] - Lowering configuration, in which cantilever 22 is lowered to a horizontal angle position.

[0066] Therefore, the crane 2 includes a lifting / lowering mechanism that acts on the boom 22 to drive angular displacement of the boom relative to the horizontal plane. The boom 22 is thus tilted to a degree that can be more or less tilted. Therefore, the lifting / lowering mechanism includes a pitch winch 3 (also referred to as a lifting winch in this boom crane configuration) that acts on a pitch rope 35 (also referred to as a lifting rope in this boom crane configuration), which is connected to the boom 22 via a return member, such as a pulley and / or a tie rod. In the illustrated example, the pitch winch 3 of the crane 2 is positioned on a relative boom 24, which extends the boom 22 at the level of the top of the mast 20.

[0067] Both crane 1 and crane 2 will use the same reference numerals to describe the pitch winch 3 and its constituent components. (Reference) Figure 3 The pitch winch 3 includes a pitch motor 30 that drives a drum 31 on which pitch ropes 35 connected to cantilever booms 12 and 22 are wound. Rotation of the drum 31 in the lifting direction causes the pitch rope 35 to wind around the drum to ensure the lifting of cantilever booms 12 and 22. Rotation of the drum 31 in the descending direction, opposite to the lifting direction, causes the pitch rope 35 to unwind around the drum 31 to ensure the descent of cantilever booms 12 and 22.

[0068] refer to Figure 4The pitch winch 3 includes a pitch motor 30, which is a rotary electric motor driven by a frequency converter 32 serving as a speed drive. The pitch winch 3 further includes a motor brake 33 associated with the pitch motor 30. Closing the motor brake 33 prevents rotation of the pitch motor 30 and the drum 31, while opening the motor brake 33 allows free rotation of the pitch motor 30 and the drum 31. Specifically, starting the pitch motor 30 is accompanied by opening the motor brake 33, and stopping the pitch motor 30 is accompanied by closing the motor brake 33.

[0069] The crane also includes a monitoring / control system 5 connected to the frequency converter 32, which monitors the motor speed of the pitch motor 30, whether during lifting or lowering, thereby monitoring the speed of the angular displacement of the booms 12, 22 during lifting and lowering. The monitoring / control system 5 is also connected to the motor brake 33 to control its opening / closing. The monitoring / control system 5 is further connected to a control unit 6 for controlling the functions of the cranes 1, 2 by the operator or crane operator, such that the monitoring / control system 5 receives instructions from the control unit 6 for controlling the pitch motor 30 via the frequency converter 32.

[0070] Reference Figure 3 The crane also includes a locking system 4 adapted to lock the pitch winch 3, and more specifically, to lock the rotation of the drum 31. The locking system 4 includes a locking plate 40 fixed to the drum 31 and provided with circumferentially distributed locking holes 41, each of which is an arcuate ellipse. Thus, each locking hole 41 extends over a given locking angle sector, for example, on the order of 3 to 10°. The locking holes 41 are evenly distributed and spaced apart from each other along a circular profile centered on the rotation axis of the drum 31. The locking plate 40 has at least six locking holes 41, or even between six and 20 locking holes 41. Each locking hole 41 has two opposing ends and a given width measured radially from the rotation axis of the drum 31.

[0071] The locking system also includes a lock 42 mounted on a fixed chassis or frame, and the lock 42 is translatable between the following configurations in a direction parallel to the rotation axis of the drum 31:

[0072] - Release configuration, wherein the lock disengages from the locking plate 40 to authorize rotation of the drum 31, and thus allows lifting / lowering of the cantilever booms 12, 22; and

[0073] - Locking configuration, wherein the lock engages within the locking hole 41 to prevent rotation of the drum 31 and thus fix the angular position of the cantilever 12, 22.

[0074] Moving lock 42 forward moves it from a released configuration to a locked configuration, and moving lock 42 backward moves it from a locked configuration to a released configuration. It should be noted that the movement of lock 42 can be performed by an actuator controlled by the monitoring / control system 5, or it can be performed manually by a field operator.

[0075] The lock 42 is in the form of a cylindrical rod, the diameter of which, within the installation tolerance, is substantially equal to the width of the locking hole 41 and less than the length of the locking hole 41, so that in the locking configuration, the lock 42 engages with the circumferential clearance within the locking hole 41. Therefore, when the lock 42 is engaged in the locking hole 41, the drum 31 has rotational freedom between two extreme positions of the lock 42 adjacent to the two corresponding opposite ends of the locking hole 41.

[0076] The crane also includes a measuring system 7 for measuring a speed parameter PM, which represents the angular velocity of displacement of the cantilever 12, 22 during lifting or lowering. The monitoring / control system 5 is connected to the measuring system 7 to receive the measured value of the speed parameter PM. It should be noted that the speed parameter PM may correspond to the angular velocity of displacement of the cantilever 12, 22, or to another speed or another parameter dependent on that angular velocity, such as the rotational speed of the drum 31, the motor speed, the speed setpoint, etc.

[0077] Optionally, the crane may include a detection system 8 that detects whether the lock 42 is in a locked or released configuration, wherein the monitoring / control system 5 is connected to the detection system 8 to receive information about the configuration in which the lock 42 is occupied. (See reference) Figure 4 The detection system 8 may include a first detector 81 in a locked configuration and / or a second detector 82 in a released configuration. Each detector 81, 82 may be a proximity sensor, contact sensor, acoustic sensor, or visual sensor, etc.

[0078] In order to lock and fix the angular position of the cantilever 12, 22, the monitoring / control system 5 is configured to perform first control of the pitch motor 30 by limiting the speed parameter PM to a first maximum speed value V1 and limiting the motor torque of the pitch motor 30 to a first torque limit value C1 to move the cantilever 12, 22 during lifting or lowering until a given angular position of the cantilever 12, 22 is reached, wherein the lock 42 is aligned with one of the locking holes 41 of the locking plate 40, which occupies the release configuration.

[0079] In other words, the first control of the pitch motor 30 enables the cantilever 12, 22 to reach the desired angular position before locking the pitch winch 3 via the locking system 4. Advantageously, the first control of the pitch motor 30 follows the forward movement of the lock 42, such that the lock 42 is substantially centered on the locking hole 41, thereby spaced apart from each end of the associated locking hole 41.

[0080] After the lock 42 is moved forward to occupy the locking configuration engaged in the aligned locking hole 41, the monitoring / control system 5 is configured to perform a second control of the pitch motor 30 by limiting the speed parameter to a second maximum speed value V2 below the first maximum speed value V1 and limiting the motor torque of the pitch motor 30 to a second torque limit value C2 below the first torque limit value C1, so as to move the cantilever 12, 22 during descent until the speed parameter PM remains at zero for a predetermined period of time to stop the pitch motor 30.

[0081] In other words, the second control of the pitch motor 30 can rotate the drum 31 in the descent direction, which is possible due to the circumferential clearance of the lock 42 within the locking hole 41, until the lock 42 abuts against one end of the locking hole 41. Therefore, once the lock 42 is in the abutting state, the rotation of the drum 31 and the pitch motor 30 is stopped, causing the speed parameter PM to be zero, and this continues for a predetermined period of time. Only at the end of this predetermined period of time with zero speed parameter PM does the monitoring / control system 5 control the pitch motor 30 to stop.

[0082] According to one possibility, the monitoring / control system 5 implements a second control of the pitch motor 30 when the detection system 8 detects that the lock 42 is in the locked configuration. In other words, the detection system 8 performs the detection of the lock 42 being in the locked configuration to authorize the second control of the pitch motor 30.

[0083] Optionally or additionally, the operator verifies that lock 42 is in the locked configuration to authorize secondary control of pitch motor 30. In other words, in order to authorize secondary control of pitch motor 30, the operator must confirm that lock 42 is in the locked configuration; for example, the operator moves lock 42 to the locked configuration in the field.

[0084] It can be assumed that the monitoring / control system 5 closes the motor brake 33 after the first control of the pitch motor 30 ends and before the lock 42 is moved in the locked configuration. Then, once the lock 42 is in the locked configuration, the monitoring / control system 5 opens the motor brake 33 to allow the second control of the pitch motor 30. After the second control of the pitch motor 30 is completed, the motor brake 33 remains open.

[0085] In order to unlock and release the angular position of the cantilever 12, 22, the monitoring / control system 5 is configured to implement a release phase starting from the third control of the pitch motor 30 by limiting the speed parameter to a second maximum speed value V2 and limiting the motor torque of the pitch motor 30 to a second torque limit value C2 to move the cantilever 12, 22 during lifting.

[0086] In other words, this third control of the pitch motor 30 enables the drum 31 to rotate in the lifting direction, causing the lock 42 to be lifted away from one end adjacent to the locking hole 41 without abutting the other end of the locking hole 41. Advantageously, the third control of the pitch motor 30 causes the lock 42 to return substantially to the center of the locking hole 41 before being moved to the release configuration.

[0087] During the release phase, the third control of the pitch motor 30 follows the backward shift of the lock 42 from the locked configuration to the released configuration. It can be assumed that the monitoring / control system 5 operates the closing of the motor brake 33 before the third control of the pitch motor 30 ends and before the lock 42 is moved in the release configuration.

[0088] After the release phase is completed, the cantilever arms 12 and 22 can be moved again at an angle, and after the lock 42 is moved to the release configuration, the monitoring / control system 5 operates the motor brake 33 to open (assuming that the motor brake 33 has been closed) and then operates the fourth control of the pitch motor 30 to move the cantilever arms 12 and 22 during lifting or lowering by limiting the speed parameter to the first value maximum speed V1 and limiting the motor torque to the first torque limit value C1.

Claims

1. A method for fixing a pitch cantilever crane (1; 2), the method being used to fix the angular position of a pitch cantilever (12; 22) that is movable during lifting and lowering by means of a pitch winch (3), the pitch winch comprising a pitch motor (30) driving a drum (31) on which a pitch rope (35) connected to the pitch cantilever (12; 22) is wound, the drum (31) being rotatably fixed to a locking plate (40) provided with circumferentially distributed locking holes (41), the fixing method performing a locking phase in which a lock (42) is displaced in the following manner: - From the release configuration, in which the lock (42) disengages from the locking plate (40) to authorize the rotation of the drum (31) and thus allow the raising / lowering of the pitch cantilever (12; 22), - To a locking configuration in which the lock (42) engages in one of the locking holes (41) after alignment to prevent the spool (31) from rotating and thus fix the angular position of the pitch cantilever (12; 22); in, The locking holes (41) are all elliptical arc-shaped, so that the lock (42) engages with the circumferential gap within the locking holes (41) in the locking configuration; and The fixing method includes the following steps: - Measure the velocity parameter (PM) during lifting or lowering, which represents the displacement angular velocity of the pitch cantilever (12; 22); - The first control of the pitch motor (30) is performed by limiting the speed parameter (PM) to a first maximum speed value (V1) and limiting the motor torque of the pitch motor (30) to a first torque limit value (C1) to move the pitch cantilever (12; 22) during lifting or lowering until a given angular position of the pitch cantilever (12; 22) is reached, in which the lock (42) is aligned with one of the locking holes (41) of the locking plate (40), and the lock (42) occupies the release configuration; - The locking phase is implemented by moving the lock (42) from the release configuration to the locking configuration; - The pitch motor (30) is controlled by limiting the speed parameter (PM) to a second maximum speed value (V2) lower than the first maximum speed value (V1) and limiting the motor torque of the pitch motor (30) to a second torque limit value (C2) lower than the first torque limit value (C1) to move the pitch cantilever (12; 22) during descent until the speed parameter (PM) is held at zero for a predetermined period of time to stop the pitch motor (30).

2. The fixing method according to claim 1, wherein, The operator performs verification of the lock (42) occupying the locking configuration in order to authorize the second control of the pitch motor (30).

3. The fixing method according to claim 1, wherein, The detection system performs a detection of the lock (42) occupying the locking configuration in order to authorize the second control of the pitch motor (30).

4. The fixing method according to claim 1, wherein, Following the second control of the pitch motor (30), the release phase is implemented through the following steps: - The third control of the pitch motor (30) is performed by limiting the speed parameter (PM) to a second maximum speed value (V2) and limiting the motor torque of the pitch motor (30) to a second torque limit value (C2) to move the pitch cantilever (12; 22) during lifting. - Perform the shift of the lock (42) from the locked configuration to the released configuration.

5. The fixing method according to claim 4, wherein, Before or after the shift of the lock (42) to the release configuration, the third control of the pitch motor (30) is followed by the closing of the motor brake associated with the pitch motor (30).

6. The fixing method according to claim 4, wherein, The displacement of the lock (42) toward the release configuration is followed by a fourth control of the pitch motor (30), which displaces the pitch cantilever (12; 22) during lifting or lowering by limiting the speed parameter (PM) to a first maximum speed value (V1) and limiting the motor torque to a first torque limit value (C1).

7. The fixing method according to claim 6, wherein, The operator performs verification of the lock (42) occupancy release configuration in order to authorize the fourth control of the pitch motor (30).

8. The fixing method according to claim 6, wherein, The detection system performs the detection of the lock (42) occupying the release configuration in order to authorize the fourth control of the pitch motor (30).

9. The fixing method according to claim 1, wherein, When the locking holes (41) extend in a given locking angle sector, the first control of the pitch motor (30) follows the forward displacement of the lock (42), which causes the lock (42) to be located in the center of the locking holes (41), and the second control of the pitch motor (30) causes the spool (31) to rotate in the descending direction according to an angle descending sector equal to half of the locking angle sector.

10. The fixing method according to claim 9, wherein, Following the second control of the pitch motor (30), the release phase is implemented through the following steps: - The third control of the pitch motor (30) is performed by limiting the speed parameter (PM) to a second maximum speed value (V2) and limiting the motor torque of the pitch motor (30) to a second torque limit value (C2) to move the pitch cantilever (12; 22) during lifting. - Perform the shifting of the lock (42) from the locked configuration to the released configuration; and The third control of the pitch motor (30) causes the drum (31) to rotate in the lifting direction opposite to the descent direction according to the tilt angle sector equal to half of the locking angle sector.

11. The fixing method according to claim 1, wherein, The pitching cantilever crane (1; 2) is a luffing jib crane (2) or a self-elevating crane (1).

12. A pitching cantilever crane (1; 2) comprising a pitching cantilever (12; 22) movable during lifting and lowering by means of a pitching winch (3), the pitching winch integrating a pitching motor (30) for driving a drum (31), on which a pitching rope (35) connected to the pitching cantilever (12; 22) is wound, the drum (31) being rotatably fixed to a locking plate (40) having circumferentially distributed locking holes (41), and the locking plate further comprising a lock (42) movable between the following positions: - Release configuration, in which the lock disengages from the locking plate (40) to authorize rotation of the drum (31) and thus allow lifting / lowering of the pitch cantilever (12; 22); and - A locking configuration in which the lock engages within a locking hole (41) to prevent rotation of the drum (31) and thus fix the angular position of the pitch cantilever (12; 22); in, The locking holes (41) are all elliptical arc-shaped, so that the lock (42) engages with the circumferential gap within the locking holes (41) in the locking configuration; and Includes: a measurement system (7) for measuring a velocity parameter (PM) representing the displacement angular velocity of the pitch cantilever (12; 22) during lifting or lowering; and a monitoring / control system (5) connected to the pitch motor (30) and the measurement system (7), the monitoring / control system (5) being configured to: - The first control of the pitch motor (30) is performed by limiting the speed parameter (PM) to a first maximum speed value (V1) and limiting the motor torque of the pitch motor (30) to a first torque limit value (C1) to move the pitch cantilever (12; 22) during lifting or lowering until a given angular position of the pitch cantilever (12; 22) is reached, in which the lock (42) is aligned with one of the locking holes (41) of the locking plate (40), and the lock (42) occupies the release configuration; - After the lock (42) is moved forward to occupy the locking configuration engaged in the aligned locking hole (41), a second control of the pitch motor (30) is performed to move the pitch cantilever (12; 22) during descent by limiting the speed parameter (PM) to a second maximum speed value (V2) lower than the first maximum speed value (V1) and limiting the motor torque of the pitch motor (30) to a second torque limit value (C2) lower than the first torque limit value (C1) until the speed parameter (PM) is held at zero for a predetermined period of time to stop the pitch motor (30).

13. The pitching cantilever crane (1; 2) according to claim 12, comprising a detection system (8) that detects whether the lock (42) is in a locked or released configuration, wherein the monitoring / control system (5) is connected to the detection system (8) to receive configuration information items regarding the lock (42) being occupied.

14. The tilting cantilever crane (1; 2) according to claim 12, wherein, The pitching cantilever crane (1; 2) is a luffing jib crane (2) or a self-elevating crane (1).

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