TWI906372B - Device for winding/unwinding a link - Google Patents

Abstract

The invention relates to a device for winding/unwinding a link adapted to transporter a fluid or transmit energy and/or signals, comprising: - a reel (2) adapted to receive said link in wound form, - a hollow through shaft (3) adapted to the passage of said link or fluid between a rotating joint and the reel, said hollow through shaft (3) being integral with the reel (2) in order to drive said reel in rotation about a longitudinal axis (X) of said shaft, - at least one permanent magnet synchronous direct drive motor, comprising a stator carrying windings (10) adapted to be electrically three-phase powered and a rotor carrying the permanent magnets (11) facing windings (10) of the stator.

Description

Device for winding/unwinding chain components

Field of Invention This invention relates to an apparatus for winding/unwinding links suitable for conveying fluids or transmitting energy and/or signals.

Background of the Invention Many industrial applications require the transmission of energy and/or signals (e.g., current, optical signals, mechanical tension, fluids, etc.) via a rotary connection between a first element and a second element that moves relative to the first element. For example, the first element may be a cabinet fixed to the ground, a robot frame, etc., and the second element may be a carriage on the ground, a mobile gantry crane, a robot arm, etc.

The aforementioned energy and/or signal are transmitted via a cable, an optical fiber or a bundle of optical fibers, a mechanical cable, a hydraulic or pneumatic fitting or any other suitable component (generally referred to herein as a "connector").

To prevent the connector from unfolding disorderly during the displacement of the second element relative to the first element, it is known to arrange the connector on the reel of a winding machine, which is mounted on the first or second element and includes a drive unit adapted to drive the reel to rotate in a manner that causes the connector to unwind or wind in a manner synchronized with the displacement of the second element relative to the first element. Such winding apparatuses are described, for example, in EP3008005.

The winding machine must be adjusted to closely approximate the application in which it is used, as applications vary greatly. Depending on the connector, the installation height, the speed and acceleration of the second element's movement relative to the first element, and the size settings of the drive unit must all be adjusted.

The characteristic of a winding machine is that the winding reel rotates at a low speed, but it must deliver a considerable amount of torque.

Different types of drive units are intended to address these technical constraints.

The first type of drive unit includes a combination of a motor and a magnetic coupler, as described in documents such as FR2102600, FR2607333, and FR2899399. This concept allows for a degree of modularity based on the same motor and coupler, as several motor-coupler assemblies can be mounted on the same gearbox to adjust torque according to the application.

The second type of drive unit includes a combination of a variable frequency motor and an electronic control unit. This type of drive unit does not benefit from the modularity of the first type because the motor must be selected to have the power required by the application. Another type of drive unit is an axial flux motor, such as those described, for example, in EP3072220.

Summary of the Invention The purpose of this invention is to design a new type of drive for winding machines that enables high torque to be obtained at low speeds.

To this end, the present invention provides an apparatus for winding/unwinding a connector suitable for conveying fluid or transmitting energy and/or signals, the apparatus comprising: - a reel adapted to receive the connector in a wound form; - a hollow shaft adapted to transfer the connector or fluid between a swivel joint and the reel, the hollow shaft being integral with the reel to drive the reel to rotate about a longitudinal axis of the shaft; - At least one permanent magnet synchronous direct drive motor includes: a stator carrying windings adapted to be three-phase powered; and a rotor carrying the permanent magnets facing the windings of the stator.

In some embodiments, at least one rotor of the at least one motor is formed from the central disc of the reel.

In other embodiments, at least one rotor of the at least one synchronous motor is rigidly integrated with the shaft. In some embodiments, the permanent magnets are configured such that their respective north faces are on one side of the rotor and their south faces are on the opposite side of the same rotor, passing through the at least one rotor.

In some embodiments, each permanent magnet has a trapezoidal shape, and the height of each permanent magnet extends radially relative to the longitudinal axis. Particularly advantageously, these magnets are juxtaposed to form a crown.

In some embodiments, the radial extension of the crown of such magnets is substantially equal to the height of the winding.

In a preferred embodiment, the motor has axial flux.

The device may further include an electronic speed changer adapted to alter the supply current of the stator windings. The device advantageously further includes: a rotary joint coupled to the end of the hollow shaft opposite the reel; and a control/command system including a processing unit coupled to or integrated into the electronic speed changer to control each motor, particularly according to the position and operating stage of the winding machine.

Detailed Description of Preferred Embodiments Figure 1 is a schematic diagram of an apparatus for winding/unwinding a chain according to one embodiment of the present invention.

The connector may be a cable, an optical fiber or a bundle of optical fibers, a mechanical cable, a hydraulic or pneumatic fitting, or any other suitable component for transmitting energy and/or signals.

For ease of reading, rotary joints, control/command devices, and components connected by links are not shown.

One of these elements may in particular, but not exclusively, be a cabinet or a frame of the robot fixed to the floor.

Others of these elements may in particular, but not exclusively, be: a carriage or mobile gantry crane on the ground, or a robotic arm.

The winding/unwinding device (also referred to as a “winding machine” in the remainder of this document) includes a support member adapted to be rigidly integrated with one of the components.

The winding machine also includes a reel 2 suitable for storing chain components in a wound form.

The reel includes: - a spindle 20 extending along the axis of rotation of the reel, and - two sets of side arms 21a, 21b, which define the amount of winding of the connector, are adapted to accommodate the turns of the connector laterally, and are fixed on either side of the spindle 20. Each set of arms forms a flange.

Alternatively (not shown), the flange of the reel can be solid, with each set of arms replaced by a disc of equal diameter.

The structure of the reel is reinforced by loops, which may be components of the spindle or flanges, namely: - an inner loop 22 located at a first distance from the spindle, and - a pair of outer loops 23a, 23b, wherein each loop is fixed to at least one arm of a respective flange at a second distance from the spindle, the second distance being greater than the first distance.

The reel includes a bearing surface adapted to receive a turn of a connector, with the inner turn contacting the bearing surface. The bearing surface may be, in particular, a portion of the spindle or an inner ring.

The flange space, that is, the distance between two flanges, is defined according to the width of the connector to be wound on the reel. In order to achieve proper winding/unwinding of the connector, especially in the case of a single-turn reel, the flange space is adjusted so that the distance between the flanges is adapted to the connector wound at the near or far end of the arm.

The flange clearance and arm length are selected based on the maximum length of the connectors that are easy to wind onto the reel, and these clearances define the reel's capacity. Depending on the application, the outer diameter of the reel is typically between approximately 3 m and 8 m.

The ends of the reel 2 and the shaft 3 are rigidly integrated, and the shaft is mounted to rotate relative to the support via the bearing 30.

As can be better seen in Figure 2, shaft 3 is hollow to allow the link to be transferred between reel 2 and a rotary joint (not shown) located on the side of the shaft opposite the reel. Therefore, the link is protected relative to the components surrounding the winding machine and is prevented from being damaged by those components.

In the case of conveying fluids via a connector, the hollow shaft itself can constitute a tube for the fluid, which is then combined with the connector and subsequently placed on the end of the shaft.

The end of the hollow through shaft opposite to the reel is coupled to a hollow through shaft coaxial with the hollow through shaft 3 in a rotary joint (not shown).

The shaft and reel are driven by a synchronous direct-drive motor via at least one permanent magnet to rotate about the longitudinal axis X of shaft 3. This type of motor is also known as a "direct-drive motor".

The at least one motor includes a stator 1, which is rigidly integrated with a support. In the drawings, the stator 1 and the support are formed from a single component, but the stator may be formed from a single component rigidly connected to the support.

According to a preferred embodiment, the stator 1 supports multiple windings 10, wherein a three-phase power supply is arranged around an axis X to generate a magnetic field along the axis X, the polarity of which alternates according to the direction of the current flowing through the windings. More precisely, the stator 1 includes multiple oriented electrical sheets 100 spaced apart from each other by radial notches, and each winding includes a set of 101 turns of conductor sliding into the notches.

The motor also includes a rotor that rotates relative to the stator 1. The rotor supports multiple permanent magnets 11.

The turns of the winding 10 are arranged in the radial direction in a manner that generates an axial magnetic field facing the permanent magnet 11 of the rotor.

In some embodiments, referring to Figures 2 to 5, the rotor is composed of a disc body 24 integral with the winding reel, on which a permanent magnet is fixed. Advantageously, the disc body may coincide with the spindle 20.

To optimize the surface covered by the magnet, the magnet advantageously has a substantially trapezoidal shape, wherein the height is radially oriented relative to axis X, and the narrowest base is positioned closer to axis X than the widest base. The base of the magnet can be straight or curved. Permanent magnets can thus be juxtaposed to form a crown coaxial with axis X, which faces the windings. Thus, as shown in Figures 3 to 5, the stator 1 includes windings 10 of varying heights, and the rotor includes trapezoidal permanent magnets 11 configured according to the crown, the width of which (corresponding to the magnet height) is preferably less than or equal to the height of the windings (measured radially relative to axis X).

In other embodiments, referring to Figures 6 through 10, rotors 41, 42 include a disc body on which a permanent magnet 11 is fixed. This disc body is not part of the reel 2 but is rigidly integrated with the hollow shaft 3. Specifically, the rotor may be formed from a single component with the hollow shaft, or rigidly fixed to the hollow shaft, for example, by grooves, pins, or any other fastening mechanism. The stator 1 is configured about the rotors 41, 42 and the hollow shaft 3 via bearings 30, which allow the hollow shaft and rotors 41, 42 to rotate relative to the stator 1. The stator 1 includes a surface facing the rotor that carries permanent magnets, which supports multiple windings 101-104, wherein a three-phase power supply is configured around an axis X to generate a magnetic field along the axis X, the polarity of which alternates according to the direction of the current passing through the windings.

More precisely, the stator 1 includes a plurality of electrical sheets spaced apart from each other by radial notches, and each winding 101-104 includes a set of multi-turn conductors sliding into the notches.

Of particular advantage, this configuration of the rotor and stator allows for the juxtaposition of several motors along axis X, each motor relating the permanent magnet-carrying surface of the rotor to the stator's facing surface and the surface supporting the windings. Thus, each rotor can be shared by two adjacent motors, with the first permanent magnet-carrying surface belonging to the first motor and the second permanent magnet-carrying surface opposite the first surface belonging to the second motor. Based on this principle, additional rotors can be added, each engaging with a separate surface of the stator, and each acting as one of the two additional motors.

Figure 6 thus shows an embodiment with four motors 51-54, the motors including two rotors 41, 42, the rotors supporting permanent magnets 111-114 on their two faces, each face of the rotor facing the respective face of the stator including the windings 101-104.

The structure shown in Figure 6 allows the number of motors to be varied between 1 and 4 depending on the number of permanent magnet surfaces of rotors 41 and 42 and the number of individual stator surfaces with windings. Naturally, additional motors can be added by providing one or more additional rotor surfaces and individual additional stator surfaces coaxial with rotors 41 and 42.

Figure 7 shows an embodiment including a rotor 41, which includes a magnet 111 on the surface facing the stator 1 including the winding 101 to form a motor 51. The rotor 41 is rigidly integrated with the shaft 3 and coaxial with the reel.

Figure 8 shows an embodiment including a rotor 41, which includes a magnet 111 on the surface facing the stator 1 including the winding 101 to form a motor 51, and a magnet 112 on the opposite surface of the rotor 41 facing the second surface of the stator 1 including the winding 102 to form a second motor 52.

These magnets can be glued, for example, to the surface of the rotor 41.

Alternatively, a single set of magnets can be used in two adjacent motors. In this case, the magnets are arranged in a manner such that the north face of one magnet is on the first side of rotor 41 and the south face is on the other side of rotor 41, and the south face of an adjacent magnet is on the first side of rotor 41 and the north face is on the other side of rotor 41. In other words, the north and south faces alternate on each side of rotor 41.

The first motor formed by the rotor 41 therefore includes a magnet on the crown, having alternating north and south faces. On opposite faces of the same rotor 41, there are crowns of magnets with opposite polarities. By offsetting the stator windings on either side of the rotor from the magnets by a certain distance, double the torque is generated relative to the crowns of magnets used on one side.

Each magnet thus has one side used by the first motor 51, while its opposite side is used by the second motor 52. For example, the rotor 41 may be made of a metal sheet that can retain the shape of the magnet, wherein the magnets 111-114 are configured to pass through the rotor 41.

In the embodiments of Figures 7 and 8, rotor 42 is not used to form a motor and therefore does not carry a permanent magnet. Naturally, to increase the compactness of the device, this rotor 42 may be removed.

Figure 9 illustrates an embodiment including motors 51 and 52 and a second rotor 42, the second rotor including a magnet 113 on the surface facing the stator 1 including the winding 103 to form a third motor 53.

Figure 10 illustrates an embodiment including motors 51 and 52 and a second rotor 42, which includes a magnet 113 on the surface facing the third surface of the stator 1 including the winding 103 to form a third motor 53, and includes a magnet 114 on the opposite surface facing the fourth surface of the stator 1 including the winding 104 to form a fourth motor 54.

Alternatively, motors 53 and 54 may be formed from the same set of magnets arranged in a manner that passes through rotor 42, such that the north face of each magnet is on one side of rotor 42 and the south face is on the other side of the same rotor 42 by alternating the north and south faces of adjacent magnets on each side of rotor 42.

The number of rotors is for illustrative purposes only and not as a limitation. Those familiar with this technique will know how to adjust the number of rotors according to the parameters of the winding device and the required torque.

In embodiments including one or more rotors 41-42 carrying permanent magnets 111-114, the permanent magnets 111-114 advantageously have a substantially trapezoidal shape, wherein the height is radially oriented relative to axis X, and the narrowest base is positioned closer to axis X than the widest base. The base of the magnet can be straight or curved. The permanent magnets can thus be juxtaposed to form a crown coaxial with axis X, which faces the winding.

Each motor is controlled by an electronic speed changer (not shown) adapted to change the voltage, frequency, and supply current of the windings of stator 1. These windings generate a magnetic field that rotates at a speed proportional to the power supply frequency, thereby causing one or more rotors to rotate, resulting in a magnetic field generated by the permanent magnets. Advantageously, the current supplied to the windings can be controlled by changing the magnetic field and thus adjusting the torque generated by the motor.

The electronic speed changer is part of the control/command system of the winding machine, which also includes a processing unit coupled to or integrated into the speed changer to control the motor, particularly based on the position and working stage of the winding machine.

The control/command system further includes sensors adapted to measure the current flowing through the windings of the motor.

The processing unit includes at least one processor and a memory, wherein the at least one processor is configured to implement computational algorithms that take into account input data, particularly from sensors, and the parameters required to execute the algorithms are recorded in the memory.

In some embodiments, the processing unit is directly integrated into the gearbox; in other embodiments, the processing unit is integrated into a programmable logic controller external to the gearbox (e.g., the gearbox of a machine to which a reel is connected).

The processing unit and the speed changer can be configured inside a cabinet located near the winding machine.

The advantage of such a direct drive motor or a set of direct drive motors is that it allows the avoidance of using any transmission components, such as gearboxes, thus overcoming all the problems caused by such gearboxes, such as any gearbox failures and backlashes, as well as losses due to their yield.

Furthermore, in this type of motor, there is no contact between the rotor and the stator 1. Therefore, there is no mechanical wear, resulting in excellent reliability and a long service life.

On the other hand, such a motor or a set of motors enables the generation of torque with a much longer duration than current asynchronous motor technology. This is important because it can reduce the braking duration of the winding machine in emergency situations (at constant motor power) or transmit torque to the winding machine's supply point more quickly in a short time (usually less than 5 seconds), which requires a stronger over-torque compared to the torque generated in normal use.

Furthermore, the winding machine according to the present invention benefits from the large size of the winding reel to allow for the configuration of a large number of permanent magnets, and these magnets are placed far from the axis X in order to generate the desired torque.

For example, a diameter of about 1.5 m is typically available for mounting the magnets. The rotational speed of the reel is typically about 30 rpm, but can generally include speeds between zero and 100 rpm. The torque generated by the motor can reach 8000 Nm.

As can be seen from Figures 3 to 10, the winding machine architecture of the present invention facilitates a certain degree of modularity in terms of the size and/or number of windings and the size of the permanent magnets.

Therefore, in the embodiment of FIG3, the stator 1 includes a winding 10 having a height h1, the top of the winding being a distance d from the axis X in the radial direction, and the height of the magnets 11 being substantially equal to the total thickness of the winding, the magnets being arranged facing the winding.

In the embodiment of Figure 4, the stator 1 includes windings 10, the height h2 of which is less than h1. Preferably, the top of the windings is at the same distance from the axis X in the radial direction as the windings in Figure 3, and the position of the base of the magnet 11 at the same distance from the axis X as the magnet of the rotor in Figure 3, in order to maximize the generated torque.

In the embodiment of Figure 5, the stator 1 includes windings 10, the height h3 of which is less than h2. Preferably, the top of the windings is at the same distance from the axis X in the radial direction as the windings in Figures 3 and 4, and the position of the base of the magnet 11 at the same distance from the axis X as the magnet of the rotor in Figures 3 and 4, in order to maximize the generated torque.

The position of the magnets and windings relative to axis X can be adjusted according to the available space and, in particular, the size of the reel.

Modularization can be achieved by forming each magnet into two or more trapezoidal portions juxtaposed in the radial direction, the sum of the heights of these trapezoidal portions forming the total height of the magnet.

Depending on the application, a magnet of maximum height can be formed by using an assembly of trapezoidal sections, or a magnet of minimum or medium height can be formed by using only a portion of such trapezoidal sections and configuring such sections as crowns.

Naturally, the embodiments shown are given for illustrative purposes only; those skilled in the art can use any other number of turns for the windings and thus determine the size and number of magnets depending on the application, torque, and required speed. Furthermore, for embodiments where one or more rotors 41, 42 are integrated with the shaft 3 (as shown in Figures 6 to 10), those skilled in the art can adjust the number of turns of windings 101-104 and determine the size and number of magnets 111-114 in the same manner. Moreover, in such embodiments, for a plurality of motors 51-54 formed from the surfaces of the rotor and stator 1, the size and number of turns of windings 101-104 and the number of magnets 111-114 can be different or the same.

Furthermore, although this specification is given with reference to an axial flux motor, according to an alternative embodiment, the motor may be a radial flux motor. In this embodiment, the rotor will include a drum integrated with a core 20 carrying a permanent magnet, and the stator 1 will carry windings in which a three-phase power supply radially oriented the magnetic field. The magnet may be placed inside or outside the windings.

1: Stator 2: Winding reel 3: Shaft 10, 101-104: Winding 11: Permanent magnet 20: Spindle 22: Inner ring 24: Disc 30: Bearing 21a, 21b: Side arm 23a, 23b: Outer ring 41, 42: Rotor 51-54: Motor 100: Electrode sheet 111-114: Magnet

Referring to the accompanying drawings, other features and advantages of the present invention will become apparent from the following detailed description, wherein: - Figure 1 is a schematic diagram of a winding/unwinding apparatus according to one embodiment of the present invention; - Figure 2 is a cross-sectional view of the winding/unwinding apparatus of Figure 1; - Figure 3 is a perspective view of the winding/unwinding apparatus of Figure 1 according to a first embodiment of a motor, showing a partial cross-sectional view of the motor; - Figure 4 is a view similar to that of Figure 3, showing a second embodiment of the motor; - Figure 5 is a view similar to that of Figures 3 and 4, showing a third embodiment of the motor; - Figure 6 is a cross-sectional view of a winding/unwinding apparatus according to another embodiment of the present invention; - Figure 7 is a perspective view of a winding/unwinding apparatus according to another embodiment of the present invention, showing a partial cross-sectional view of the stator; - Figure 8 is a view similar to that of Figure 7, showing two juxtaposed motors; - Figure 9 is a view similar to that of Figures 7 and 8, showing three juxtaposed motors; - Figure 10 is a view similar to that of Figures 7 to 9, showing four juxtaposed motors.

Only the components required to describe the winding machine are shown. The same component symbols in different figures represent the same components or components that perform the same function, so there is no need to describe them in detail again.

1: Stator 3: Shaft 10, 101: Winding 11: Permanent Magnet 21a, 21b: Side Arm 22: Inner Ring 24: Disc 30: Bearing 100: Electrode Sheet

Claims (8)

An apparatus for winding/unwinding a link suitable for conveying a fluid or transmitting energy and/or signals, the apparatus comprising: a reel (2) adapted to receive the link in a wound form; and a hollow shaft (3) adapted to transmit the link or fluid between a swivel and the reel, the hollow shaft (3) being integral with the reel (2) to drive the reel to rotate about a longitudinal axis (X) of the hollow shaft. A synchronous motor directly driven by at least one permanent magnet, the at least one synchronous motor comprising a stator and a rotor, the stator carrying several windings (10) adapted to be three-phase powered, the rotor carrying several permanent magnets (11) facing the windings (10) of the stator, the at least one rotor of the at least one synchronous motor being formed by a central disc (24) of the reel (2) or rigidly integrated with the hollow through shaft (3). The apparatus as described in claim 1, wherein at least one rotor of the at least one synchronous motor is rigidly integrated with the hollow through shaft (3), and the permanent magnets are configured to pass through the at least one rotor (41) such that each permanent magnet has a north face on one side of the rotor (41, 42) and a south face on the opposite side of the same rotor (41, 42). The device as described in claim 1 or 2, wherein each permanent magnet (11) has a trapezoidal shape and the height of each permanent magnet extends radially relative to the longitudinal axis (X). The device as described in claim 3, wherein the permanent magnets (11) are juxtaposed to form a crown. The device as described in claim 4, wherein the radial extension of the crown of the permanent magnets (11) is substantially equal to the height of the windings (10). The apparatus as described in claim 1 or 2, wherein the motor is an axial flux motor. The apparatus as described in claim 1 or 2 further includes an electronic speed changer adapted to change the supply current of the windings of the stator. The device as described in claim 7 further includes: a rotary joint coupled to one end of the hollow shaft (3) opposite to the reel (2); and a control/command system including a processing unit coupled to or integrated into the electronic gearbox to control each motor, particularly according to the position and operating phase of the device.