Linear motor system, corresponding forming assembly and method - Patents.com

Abstract

A linear motor system is described, comprising a track (1), at least one movable member (2) coupled to the track (1) and configured to move along the track (1), the at least one movable member (2) comprising a first element (20), a second element (21) movable relative to the first element (20), at least one motion detector (22) configured to transmit an actuation signal (M) and comprising at least one magnet (226) arranged on one of the first element (20) or the second element (21) and at least one magnetometer (224) arranged on the other of the first element (20) or the second element (21), and a processing unit (5, 23) configured to calculate the movement of the second element (21) as a function of the actuation signal (M) received from the motion detector (22).

Description

[Technical field]

[0001] The present invention relates to a linear motor system including one or more tracks and a movable member coupled thereto. The linear motor system according to the invention can be used in industrial applications, for example in forming assemblies for forming a plurality of objects, such as packaging assemblies configured to form and seal a plurality of packs containing pourable products, in particular pourable food products. [Background technology]

[0002] Linear motor systems are known and used in industrial applications to improve efficiency and flexibility. Such linear motor systems include multiple moveable members that are independently movable along one or more tracks. For example, a linear motor system may include independent carts that are movable along a race track.

[0003] For example, it is known to use forming assemblies such as packaging assemblies having a plurality of movable members movable independently of one another on a track and configured to form and / or seal objects such as packages of sterilized packaging material configured to receive pourable food products such as fruit juice, UHT (ultra-high temperature treated) milk, wine, tomato sauce, etc.

[0004] These packages are usually produced in fully automatic packaging assemblies, where a continuous tube is formed from a web of packaging material fed into such packaging assembly. To obtain the final package, the web is folded longitudinally and sealed to form a tube which is fed along a vertical direction. The tube is then filled from above with the sterilized food product, sealed and cut along equally spaced cross sections.

[0005] Although functionally effective, known linear motor systems remain open to further improvement. A need is felt for improved (optionally continuous) movement (e.g. position) control of a portion of a moveable member and / or a moveable member along a trajectory, which may improve correct operation of a linear motor system.

[0006] As with any mechanical system, all components are subject to mechanical play that can reduce the overall stiffness and therefore the repeatability of the overall system. Thus, in a molding assembly, movement control of each moving member and / or its moving parts can facilitate correct handling, i.e., molding and sealing of the packages and / or facilitate detection of early deterioration of performance. For example, a processing unit within a moving member of the system may not have precise position control, and measurements detected from sensors located on the moving members may therefore be inaccurate.

[0007] The need for (continuous) position control of moving parts of a moving member, for example parts which are movable relative to one another, is felt. Summary of the Invention [Problem to be solved by the invention]

[0008] It is an object of the present invention to provide a linear motor system which can facilitate achieving one or more of the above needs in a simple and cost-effective manner. Such object is achieved by a linear motor system and a corresponding method having the features set forth in the following claims.

[0009] Such objectives can be achieved by a molding assembly for forming one or more objects, such as a packaging assembly for forming and sealing a plurality of packs, the molding assembly comprising a linear motor system according to one or more embodiments.

[0010] The disclosed embodiments may achieve, for example, one or more of the following advantages: The movement of the moving parts relative to one another can be monitored in real time (precisely). -Position control reduces handling of defective products. - The correct connection of the moving parts and the tracks can be monitored. -For example, defects or damage to moving mechanical parts caused by play over time or sticking of parts can be detected early on. - Errors in the relative positioning of the moving parts can be detected. - The key movements of moving parts, such as forming and sealing in the case of a packaging assembly, can be measured and monitored directly on the moving parts. [Means for solving the problem]

[0011] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: FIG. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a schematic diagram showing details of a linear motor system according to one or more embodiments. [Diagram 2] FIG. 2 is a non-limiting example of an exploded perspective view of the movable members of a packaging assembly with parts removed for clarity. [Diagram 3] FIG. 2 is a schematic diagram illustrating details of a motion detector according to one or more embodiments. [Figure 4] FIG. 1 illustrates a flowchart of a method for calculating a position according to one or more embodiments. [Diagram 5] FIG. 2 illustrates details of a linear motor system in accordance with one or more embodiments. [Figure 6] FIG. 2 illustrates details of a linear motor system in accordance with one or more embodiments. [Figure 7] FIG. 1 illustrates an example sensitivity function of a magnetometer in accordance with one or more embodiments. [Figure 8] FIG. 2 is a schematic diagram showing details of a linear motor system according to one or more embodiments. [Figure 9]1 illustrates a schematic front view, with parts removed for clarity, of a packaging assembly for forming a plurality of sealed packs according to the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] FIG. 1 shows an example of a linear motor system according to one or more embodiments. The arrangement of permanent magnets and coils, i.e., the moving member and respective tracks, define this type of linear motor and are configured to independently control the movement of the moving member along each track in a known manner. The tracks may comprise a single rail or multiple rails. The rails may be closed or open, like a race track.

[0014] The linear motor system comprises one or more tracks 1, e.g., a single track in Fig. 1 for simplicity, and one or more movable members 2, preferably movers or carts, coupled to the track 1 and configured to move along the respective track 1 in a direction X, illustrated by an arrow in Fig. 1. For example, the track 1 defines an infinite path along which the movable members 2 are configured to move in a cyclical manner.

[0015] Each movable member 2 is a first element 20, for example the body of the mobile member 2, a second element 21 movable relative to the first element 20, as will be explained in more detail below with reference to FIG. 2; one or more motion detectors 22, for example attached to the movable member 2, configured to transmit, for example wirelessly, a motion signal M indicative of a movement of the movable member 2, the first element 20 and / or the second element 21; Equipped with.

[0016] The linear motor system further comprises a processing unit, e.g. a processing unit 23 of the movable member 2 or a system control and processing unit 5, which is configured to calculate the movement of the first and / or second element 20, 21, e.g. to calculate the position of the second element 21 relative to the first element 20 as a function of the movement signal M received from the movement detector 22 and optionally a predefined initial position. Additionally or alternatively, the processing unit 5, 23 may be configured to calculate the movement of the movable member 2, e.g. to calculate the position of the movable member 2 relative to the track 1 as a function of the movement signal M received from the movement detector 22 and optionally as a predefined initial position. Additionally or alternatively, the processing unit 5, 23 may be configured to calculate the movement of the movable member 2, e.g. to calculate a vibration pattern of the movable member 2, the vibration pattern being indicative of a coupling of the movable member 2 to the track 1. The vibration may be caused by friction between the movable member 2 and the track 1 when the movable member 1 slides on the track 1.

[0017] The processing unit 5, 23 may be configured to interrupt the movement of the movable member 2 and / or send an alarm signal to the user interface if the calculated position and / or vibration pattern (of the movable member 2, the first element 20 and / or the second element 21) differs from a predefined position and / or a predefined vibration pattern, respectively. The predefined position and / or the predefined vibration pattern may be indicative of a healthy movable member 2 movement.

[0018] The processing unit 23 of the movable member 2 may be configured to receive, for example wired or wirelessly, a motion signal M from one or more motion detectors 22. The processing unit 23 of the movable member 2 may be wirelessly coupled to a system control and / or processing unit 5, which may be arranged on the track 1. For example, the processing unit 23 may be configured to transmit data to the system control and / or processing unit 5 during each cycle as the respective movable member 2 passes. The transmission of data between the movable member 2 and the system control and / or processing unit 5 may be performed by a (for example low energy) wireless transmission module, for example a Bluetooth® low energy transmission module. The processing units 5 and / or 23 may be configured as follows: - monitoring the movement of the moving member relative to the moving member; and / or - Identifying faults or errors at an early stage, for example as a function of the calculated position and / or velocity and / or acceleration.

[0019] If a fault or error is identified, the processing unit 5, 23 may be configured as follows: - generating an alarm signal indicating a detected error; and / or - interrupting the movement of the movable part 2;

[0020] Thus, the linear motor system may include a user interface configured to display the alarm signal.

[0021] A user can decide which part of the movable member 2 to monitor based on, for example, its position control relevance and the possibility that a failure of the part may cause an error in the motion flow of the linear motor system.

[0022] In industrial applications, the movable member 2 is configured to perform certain automated operations such as gripping, cutting, forming, etc. In order to perform the operations accurately, it is desirable to monitor the position of the parts of the movable member 2. This is possible by means of a motion detector 22 configured to detect the movement of the movable member 2 and / or parts thereof relative to a known initial position.

[0023] FIG. 2 illustrates a known type of movable member 2 used in a packaging assembly for forming and sealing a package, and is an exploded perspective view of the movable member of the packaging assembly with parts removed for clarity. This type of movable member 2 is described herein for clarity and ease of understanding, but the movable member 2 is not to be construed as being limited thereto. The movable member 2 may comprise a body 200 configured to be coupled to the track 1. The body 200 may be configured to slide on the track 1 along a direction X illustrated in FIG. 2. The forming unit 202 and the sealing unit 204 may be coupled to the body 200, for example directly. The forming unit 202 may comprise a body 206 and a movable element 207 configured to move along a second direction Y perpendicular to the first direction X. The forming unit 202 may comprise a half shell comprising a rear wall 208 and a flap 210 connected directly or indirectly to the movable element 207 of the forming unit 202. The forming unit 202 may further comprise a hinge 211 connected to the flap 210. The flap 210 may be configured to rotate along an axis parallel to the first direction X.

[0024] The forming unit 202 may be configured to move relative to the sealing unit 204 along a first direction X.

[0025] The sealing unit 204 may include a sealer 212 and may be configured to move along a second direction Y relative to the body 200 .

[0026] In one or more embodiments, by way of non-limiting example, the first element 20 and the second element 21 may be: the main body 200 and the main body 207 of the forming unit 202, the movable element 207 and the body 206 of the forming unit 202 - flap 210 and rear wall 208, the body 206 of the forming unit 202 and the sealing unit 204; - a body 200 and a sealing unit 204, The present invention may also include:

[0027] The movable member 2 may comprise a plurality of motion detectors 22 and a plurality of first and second elements 20, 21, respectively, as described above. Each motion detector 22 of the plurality of motion detectors 22 may be configured to detect movement of a respective first element 20 and / or second element 21 in the plurality of first and second elements 20, 21. Each motion detector 22 may be configured to generate a respective motion signal M indicative of movement of a respective monitored element 20, 21.

[0028] The second element 21 may, for example, be directly coupled to the first element 20 and configured to move relative thereto. The movement of the second element 21 may be linear, for example, away from or toward the first element, as depicted by the arrows in the non-limiting example of FIG. 1, or may be angular, for example, forming an angle with respect to the first element 20.

[0029] One or more motion detectors 22 may be attached to a surface of the first or second elements 20,21.

[0030] In one or more embodiments, the one or more motion detectors 22 may comprise an inertial sensor, e.g., a MEMS accelerometer, such as an inertial measurement unit (IMU) comprising a 3D accelerometer and a 3D gyroscope with digital output, i.e., the inertial sensor may comprise one or more motion sensors 220, such as a (3D) acceleration sensor, and / or one or more rotation sensors 222, such as a (3D) gyroscope, as shown in FIG.

[0031] The processing unit 5, 23 may calculate the movement of the movable member 2 by means of an Inertial Navigation System (INS) and calculate the position, orientation and velocity (direction and speed of movement) of the movable member 2 by dead reckoning without the need for external references. By utilizing the strapdown inertial navigation principle, it is possible to monitor the relative motion (rotation and displacement) by integrating the sensor readings over time.

[0032] For example, the motion sensor 220 may be calibrated with respect to an initial reference coordinate system that may define a predetermined initial position. The rotation sensor 222 may be configured to measure a signal indicative of angular movement. The processing unit 5, 23 may be configured to compensate the data collected by the motion sensor 200 with the data collected by the rotation sensor 222. In this way, the position calculated as a function of the motion signal M can remain accurate with respect to the initial reference coordinate system.

[0033] For example, the processing unit 5, 23 may be configured to calculate the position of the mobile member 2 and / or the one or more elements 20, 21 as a function of a motion signal M indicative of an acceleration and / or a motion signal M indicative of an angular velocity detected by the inertial sensor(s). The inertial sensors arranged on the first and second elements 20, 21 allow for precise control of the motion of the parts of the mobile member 2, i.e. the elements 20, 21 configured to move, for example to form and seal a package, can be monitored. The inertial sensors allow positioning errors of the elements 20, 21 to be detected.

[0034] Additionally or alternatively, inertial sensors allow precise position control of the movable member 2 along the trajectory 1. In this way, potential errors in the positioning of the movable member 2 can be detected.

[0035] In other words, the motion detector 22 comprises a (3D) motion sensor 220 and a (3D) rotation sensor 222, and the processing units 5, 23 may be configured as follows: receiving a motion signal M comprising a first signal M1 indicative of acceleration from the motion sensor 220 and a second signal M2 indicative of angular velocity from the rotation sensor 222; - calculating the acceleration as a function of the first signal M1, - calculating the angular velocity as a function of the second signal M2; - Calculating the position, orientation and / or velocity of the movable member 2 and / or its elements 20, 21 as a function of the calculated acceleration and angular velocity.

[0036] These calculations are performed with respect to a given initial position or initial reference coordinate system.

[0037] 4 shows a flow chart of a method for calculating the position of the movable member 2 and / or its elements 20, 21, which may be performed by the processing unit 5, 23. It will be understood that the same calculations may be performed by the processing unit 23 of the movable member 2 and / or by the system control and / or processing unit 5.

[0038] The processing unit 5, 23 may be configured for a motion detector 22 configured to measure the movement of the first or second element 20, 21 as follows: -1000, receiving a motion signal M including a first signal M1 indicative of a (3D) acceleration of the first or second element 20, 21; - 1002, receiving an operating signal M including a second signal M2 indicative of a (three-dimensional) angular velocity of the first or second element 20, 21; 1004, calculating the orientation of the first or second element 20, 21 as a function of the second signal M2 and an initial estimate of the orientation of the first or second element 20; 1006, calculating the acceleration of the first or second element 20 as a function of the first signal M1, the calculated direction, and optionally the initial reference frame; -1008, calculate the gravitational acceleration correction as a function of the calculated direction, -1010, sum the calculated acceleration and gravity acceleration correction, -1012, calculating the position of the first element 20 or the second element 21 as a function of the sum and a given initial position.

[0039] In one or more embodiments, in addition to or instead of determining the position of the movable member 2 and / or the elements 20, 21, the motion detector 22 may be configured to detect vibrations of the movable member 2, for example due to a preload, i.e. the movable member 2 is coupled at its lateral ends to the track 1, sliding of the movable member 2 on the track 1 causes vibrations which may be detected by the motion detector 2. The processing units 5 and / or 23 may be configured to receive a motion signal M indicative of a vibration measurement and to calculate the response of the movable member 2 to vibrations over frequency as a function of the motion signal M. The motion signal M may preferably include an acceleration.

[0040] In one or more embodiments, the movable member 2 may include a motion sensor 220, as illustrated in Figure 5, and may include a number of motion detectors 22 spaced apart from one another on the elements 20, 21 of the movable member 2. In other words, the motion sensors 220 may be located at different positions on the same element 20, 21, for example at opposite lateral ends thereof.

[0041] The processing unit 5, 23 may be configured as follows: receiving motion signals M from a plurality of motion detectors 22, the signals M being indicative of the respective accelerations of the elements at their positions; - Check whether the movement signals M differ from each other, for example by more than a predefined amount. This may be done by checking whether the acceleration, or other metric based on the acceleration, for example some indication in the frequency spectrum, differs (over time) by more than a predefined amount, for example indicating a correct coupling of the movable part 2 to the track 1.

[0042] If such response does not correspond to a predetermined frequency response pattern, the processing unit 5, 23 may be configured to interrupt operation of the one or more moveable members 2 and / or send an alarm signal to a user interface.

[0043] That is, by detecting the acceleration difference, a potential tilt of the movable member 2 gliding on the track 1 can be detected insofar as one side of the movable member 2 has a different acceleration, speed and / or position with respect to the other side. Thus, the stability of the connection between the movable member 2 and the track 1 can be precisely controlled. In this way, potential errors in the positioning of the movable member 2 can be detected.

[0044] One or more motion detectors 22 may be embedded in epoxy and fixed to the movable member 2. Optionally, the motion detectors 22 may be fixed to the first and / or second elements 20, 21. Advantageously, in this way the inertial sensor may be made substantially waterproof and shock resistant.

[0045] The motion sensor 220 and rotation sensor 222 may be calibrated before use, for example after installation in a linear motor system. Calibration may include the following configurations (performed, for example, by the processing units 5, 23): - Defining error models for the sensors 220, 222 and automatically calculating the calibration parameters of the error models. -The sensor fusion algorithm (EKF) minimizes integral drift caused by measurement errors of acceleration and angular rate, integrates them to obtain velocity, and then integrates them again to obtain position.

[0046] To minimize integral drift, the linear motor system may include a synchronizer configured to transmit a synchronization signal with each cycle, as described in more detail below. In this way, a spatial reference is provided to the movable member. The synchronization signal allows the predetermined initial position to be updated.

[0047] In one or more embodiments, in addition to or instead of the inertial sensor, as shown in FIG. 6, the motion detector 22 may comprise one or more magnets 226 arranged on one of the first or second elements 20, 21 and one or more magnetometers 224, e.g., one or more Hall sensors or anisotropic magnetoresistance (AMR) sensors, arranged on the other of the first or second elements 20, 21. In a non-limiting example, the magnet 226 may be arranged on the second element 21 configured to move linearly along the illustrated arrow, and the magnetometer 224 may be arranged on the first element 20. The generated motion signal M may be indicative of a magnetic field at the one or more magnetometers 224, where a magnetic field that changes as a function of the movement of the first and / or second elements 20, 21 is measured. For example, the motion signal M may include a measurement of the magnetic field generated by the magnet 226, e.g., a plurality of signals M3 received from the magnetometer 224 indicative of the movement of the magnet 226.

[0048] The magnetometers 224 may be arranged in an array. As shown in FIG. 6, in one or more embodiments, the magnetometers 224 may be arranged to form a cross shape. Optionally, the magnetometer 224 may be located at the center of the cross. The cross-shaped arrangement of the magnetometers 224 may have one or more advantages, such as facilitating ensuring good range of motion detection while maintaining low sensitivity of the cross-directional alignment between the magnetometers and the magnet.

[0049] The motion detector 22 may include magnetometers 224a, 224b of different types with respect to their sensitivity. For example, the magnetometer 224a in the center of the cross may have a higher sensitivity relative to the remaining magnetometers 224b of the motion detector 22.

[0050] FIG. 7 shows an example of the sensitivity S of a conventional magnetometer 224, which, for example, drops exponentially as a function of distance d. The two curves represent an example of the sensitivity of magnetometer 224b with low sensitivity relative to magnetometer 224a with high sensitivity. As shown, magnetometer 224b can measure the difference in the magnetic field at a larger distance d relative to magnetometer 224a. In other words, magnetometer 224b may be configured to detect the magnetic field in a first distance interval d1-d2, while magnetometer 224a may be configured to detect the magnetic field in a second distance interval d3-d4. The higher distance of the second interval, i.e. d4, may be longer than the higher distance of the first interval, i.e. d2.

[0051] In one or more embodiments, the magnet 224 may be aligned with the magnetometer 224a located at the center of the cross. The alignment may be with respect to an axis X1 parallel to the direction of relative movement of the second element 21 with respect to the first element 20, illustrated here as the linear direction X.

[0052] For example, if the alignment of the magnet with respect to the magnetometer changes, this arrangement can at least partially correct errors resulting therefrom.

[0053] The magnetometer 224 and magnet 226 may be disposed on opposing surfaces of the first and second elements 20, 21. Preferably, the magnetometer 224 is disposed on the first element 20 and the one or more magnets 226 are disposed on the second element 21.

[0054] The magnetometer 224 may be coupled, for example directly, to a processing unit 23 of the movable member 2 and may be configured to transmit thereto an operating signal M comprising a third signal M3 indicative of the magnetic field at the magnetometer 224. The processing unit 5 and / or 23 may be configured to calculate the position of the second element 21 relative to the first element 20 as a function of the operating signal M comprising the third signal M3.

[0055] The processing units 5 and / or 23 may be configured to perform data fusion of the data of one or more magnetometers 224, for example by integrating the data from each magnetometer. This is performed to generate more consistent, accurate and useful information, e.g. better performance of the moving parts and measurement range, than the information provided by the individual magnetometers 224. Thanks to the magnetic model obtained from the multiple magnetometers 224, the relative position can be determined with an error of ±0.1 mm for 30 mm.

[0056] The movable member 2 may include one or more temperature sensors (not shown) in close proximity to the magnetometer. The processing unit 23 may be configured to receive the temperature from the temperature sensor and correct the data measured by the magnetometer 204 as a function of temperature. For example, Hall sensors are sensitive to temperature and a temperature sensor may improve detection if the linear motor system is placed in an environment subject to temperature fluctuations.

[0057] If the motion detector 22 comprises both inertial sensors 220, 222 and magnetometers and magnets 224, 226, the processing units 5, 23 may be configured to calculate the position of the second element 21 relative to the first element 20 as a function of the first, second and third signals M1, M2, M3.

[0058] In one or more embodiments, the linear motor system includes a power supply 4 that can be coupled to the movable member 2 to supply power to the movable member 2. The power supply 4 can be temporarily electrically coupled to the movable member 2 in a predetermined power supply area.

[0059] The power supply 4 may comprise an electrical pulse generator or a transformer and may be temporarily electrically coupled to the moving member 2. The electrical pulse generator or the transformer may be used for sealing purposes. For example, the moving member 2 may be electrically coupled to a stationary power supply 4 while passing through a power supply area.

[0060] The movable members 2 may each include a power supply module 24 configured to receive power from a power supply device 4 and redistribute it to electronic components within the movable member 2. For example, the power transfer may consist of an electrical pulse from the power supply device 4 to the power supply module 24. The power supply device 4 may be configured to electrically couple to the power supply module 24 of the movable member 2 when the movable member 2 is transitioned by the power supply device 4.

[0061] As discussed above and illustrated in FIG. 8 , in one or more embodiments, the linear motor system may include a synchronizer 3 configured to transmit a synchronization signal S, for example, for each cycle of the movable member 2. The movable member 2 may include a synchronization sensor 25 configured to detect the synchronization signal S. The synchronization sensor 25 may be coupled, for example directly, to a processing unit 23 configured to receive a motion signal M from the motion detector 22. The motion signal M may be adjusted as a function of the synchronization signal S.

[0062] The processing units 5 and / or 23 may be configured to calculate the movement of the movable member 2 and / or the first element 20 and / or the second element 21 as a function of the synchronization signal S.

[0063] For example, a predetermined initial position of the movable member 2 on which the positions of the first and / or second elements 20, 21 are calculated may be adjusted as a function of the synchronization signal S, for example the initial position may be reset upon receipt of the synchronization signal S.

[0064] The system control and / or processing unit 5 may be coupled, for example wirelessly, to the synchronizing device 3. The system control and / or processing unit 5 may be configured to transmit an enable signal indicating that the moveable member 2 is positioned in a predefined synchronization area. The synchronizing device 3 may be configured to transmit a synchronization signal S when the enable signal is received by the synchronizing device 3.

[0065] The synchronization device 3 may comprise an optical transmitter, preferably an IR transmitter, configured to transmit an optical synchronization signal S, and the synchronization sensor 25 may comprise an optical sensor, preferably an IR receiver, configured to detect the optical synchronization signal S.

[0066] The optical sensor may be configured to detect an optical (IR) synchronization signal S consisting of a frequency modulated signal. The optical (IR) synchronization signal S may have a predetermined carrier frequency bandwidth, preferably 20-50 kHz, more preferably 38 kHz. That is, the optical sensor can only detect signals of the predetermined bandwidth. Therefore, the optical signal transmitter is configured to transmit the synchronization signal S with the predetermined carrier frequency bandwidth.

[0067] The synchronizing device 3 may be located immediately upstream of the operating area of ​​the movable part 2, i.e. a handling area such as a forming area, a sealing area, etc. Thus, the synchronization is performed just before the movable part 2 starts the designed automated operation.

[0068] The synchronisation device 3 may for example be constituted by the power supply device 4. In this case, the synchronisation sensor 25 is arranged to detect a synchronisation signal S indicative of a power transfer between the power supply device 4 and the power supply module 24.

[0069] Advantageously, the synchronization signal S makes it possible to reduce drift effects in the case of inertial sensors.

[0070] As shown in Fig. 9, one or more embodiments refer to a forming assembly 7 configured to form one or more objects 80. In the following, a non-limiting example of a packaging assembly 7 is shown, configured to form and seal a number of packs 80 containing a pourable product, preferably a pourable food product, starting from a tube 8 of packaging material. In the following, reference is made to a packaging assembly 7, but it will be understood that this is merely a non-limiting example for the sake of clarity and brevity. There may also be different types of forming assemblies 7 that are not packaging assemblies. All the features described below, even if they relate to a packaging assembly 7, can be more generally applied to the forming assembly 7.

[0071] The tube 8 is formed in known manner by longitudinally folding and sealing a web of packaging material (not shown). The tube 8 is then filled with pourable product from above by a pipe (not shown) and fed through the packaging assembly 7 along a linearly advancing direction X. In particular, the tube 8 extends along a linear longitudinal, e.g. vertical, axis parallel to the direction X.

[0072] The forming assembly 7, e.g. the packaging assembly 7, is equipped with a linear motor system according to one or more embodiments as described above. a pair of conveyors 70 arranged at a distance from each other on either side of the tube 8 and adapted to cooperate with the tube 8; an exit conveyor 72 arranged in a staggered manner with respect to the axis X and positioned below the conveyor 70; Equipped with.

[0073] Each conveyor 70 substantially comprises an endless track 1 and a number of movable members 2, preferably movable members, coupled to a respective one of the tracks 1 and cyclically movable along the respective one of the tracks 1. Each movable member 2 is configured to slide cyclically along the track 1 of the respective conveyor 70. The plurality of movable members 2 slide along the respective track 1 in use.

[0074] The forming assembly, e.g. the packaging assembly 7, a pair of endless tracks 1 between which a tube 8 is fed along a (for example linear) forward direction X; a pair of movable members 2, each of which is movably coupled to a respective one of the tracks 1 and is cyclically movable along the tracks 1; Equipped with.

[0075] As shown in the exploded perspective view of a pair of movable members 2 in FIG. 2, each of the movable members 2 may be A first element 20; and a second element 21 movable relative to the first element 20; a respective forming unit 202 and optionally a respective sealing unit 204 linearly movable towards the tube 8 along a direction Y transverse to the forward direction X so as to contact and periodically cooperate with successive tube portions 82 to respectively form and optionally seal at least corresponding pack portions of each pack 80; Equipped with At least one movable member 2 of the pair is provided with one or more motion detectors 22 configured to transmit a motion signal M indicative of, for example, the movement of the at least one movable member 2, the first element 20 and / or the second element 21.

[0076] The forming assembly 7 further comprises a processing unit 5, 23 configured to calculate a movement of the movable member 2 and / or the first and / or second element 20, 21, e.g. the position of the movable member 2 relative to the track 1 and / or the position of the second element 21 relative to the first element 20, as a function of the movement signal M received from the movement detector 22. Additionally or alternatively, the processing unit 5, 23 may be configured to calculate a vibration pattern of the movable member 2 as a function of the movement signal M, the vibrations occurring while the movable member 2 is gliding on the track 1.

[0077] As shown in Figure 9, the two tracks 1 define respective infinite paths P, Q located on opposite sides of the tube 8. More specifically, the paths P, Q are: a respective, preferably linear, actuating branch P1, Q1 along which a tube 8 is provided and along which a movable member 2 cooperates with the tube 8; a respective return branch P2, Q2 along which the movable member 2 is separated from the tube 8; Equipped with.

[0078] According to this preferred embodiment, the paths P, Q are substantially elliptical.

[0079] In use, when sliding along the respective actuating branches P1, Q1, each movable member 2 cooperates with a corresponding movable member 2, i.e. the movable members 2 cooperate with each other two by two, defining a pair of movable members 2 which oppose each other, cooperate with each other and cooperate with the tube 8 while sliding along the actuating branches P1, Q1.

[0080] Each pair of movable members 2 is configured to cooperate with the tube 8 to cyclically form and seal one puck 80 at a time, as shown in FIG. 4, and cut the puck 80 to separate it from the tube 8.

[0081] For this purpose, each mobile member 2 comprises, on one side thereof, a forming unit 202 and a sealing unit 204 arranged to cooperate with the tube 8 along the respective working branch P1, Q1.

[0082] The forming units 202 are configured to cooperate with each tube portion 82 of the tube 8 to form at least a corresponding pack portion, more particularly a corresponding pack 80. For this purpose, each forming unit 202 is preferably movably mounted by a respective movable member 2. The forming units 202 may preferably comprise a half-shell presenting a C-shaped cross-section and comprising a rear wall 208 and a pair of lateral flaps 210. In the illustrated embodiment, the flaps 210 are movably connected to the wall 208. The flaps 210 project from and are hinged to opposite lateral edges of the wall 208 when the movable member moves along the actuation branches P1, Q1.

[0083] In use, the half shells of each forming unit 202 are configured to sequentially and cyclically contact and cooperate with the tube portions 82 to form at least a pack portion of a respective pack 80 .

[0084] Each half shell is linearly movable transversely, for example orthogonally, to the direction X, i.e. along the direction Y, towards the tube 8, i.e. towards the tube part 82 which it has to form. Each forming unit 202 comprises a mobile element 207 linearly movable along the direction Y, which mobile element carries the respective half shell.

[0085] The sealing unit 204 is configured to cooperate with the tube 8 to seal the tube portions 82 at successive cross sections transverse to the direction X at predetermined equal intervals. Furthermore, the sealing unit 204 is configured to cooperate with the tube 8 to cut the packs 80 at the cross sections to separate the packs 80 from one another.

[0086] On the one side, each sealing unit 204 is mounted downstream of the corresponding forming unit 202 of the respective movable member 2 along the respective path P, Q and comprises a counter-sealing device and a removable cutting element, for example a knife (not shown). On the other hand, each sealing unit 204 is mounted downstream of the corresponding forming unit 202 of the respective movable member 2 along the respective path P, Q and comprises a sealing device and a seat adapted to receive the knife of the corresponding sealing device configured to cooperate with the counter-sealing device. The sealing device may comprise an ultrasonic sealing device, an induction heating sealing device or an induction heating sealing device.

[0087] As shown in FIG. 9, when the forming unit 202 and the sealing unit 204 are advanced by the respective movable members 2 along the respective operation branches P1, Q1, the respective half shells, sealing devices and counter-sealing devices are a closed or operative position in which the half shells, closures and counter-closures cooperate with respective tube portions 82 to form, seal and sever respective packs 80; and an open or idle position in which the half shells, closures and counter closures are removed from the tube 8 or from the formed pack 80; moves back and forth along direction Y between

[0088] When the half shells are in the operative (closed) position, the flap 210 of each half shell rotates about its respective hinge, for example about an axis parallel to the direction X, from a position away from the respective wall 208 to a position substantially perpendicular to the wall 208, facing the flap 210 of the other half shell carried by the corresponding mobile member 2 of the same pair and contacting the tube 8 so as to completely surround the respective tube portion 82 destined to form the respective pack 80. When the two half shells of the two respective forming units 202 of a pair of cooperating mobile members 2 are together in the operative (closed) position, they define a substantially prismatic cavity and accordingly control the volume and the shape of one respective pack 80 to be formed.

[0089] When the counter-sealer and the sealer of the pair of cooperating movable members 2 are in the operative (closed) position, they cooperate with each other to heat seal the tube 8 to form upper and lower sealing bands. Then, the respective cutting elements are removed and cut the packs 80 between the upper and lower sealing bands of two adjacent packs 80 to separate the formed packs 80 from each other.

[0090] As illustrated in FIG. 9, further movement occurs between the sealing unit 204 and the forming unit 202 along direction X to form the top and / or bottom of the puck 80 .

[0091] A motion detector 22 according to one or more embodiments may be disposed on the movable member 2 to monitor one or more of the aforementioned movements.

[0092] Thus, the first and / or second elements 21 may comprise the body 200 of the movable member 2, one or more components 206, 207, 208, 210 of the forming unit 202, and / or one or more components 204, 212 of the sealing unit 204. For example, the forming assembly 7 may include a plurality of motion detectors 22 configured to detect movement of the plurality of first and / or second elements 20, 21. The plurality of first and / or second elements 20, 21 may be any combination of relatively movable parts of the movable member 2, as described above.

[0093] As a non-limiting example, the monitoring of vertical movement between the forming unit 202 and the sealing unit 204 is discussed herein.

[0094] The motion detector 22 may optionally comprise one or more inertial sensors 220, 222 arranged on a surface of the body 206 of the forming unit 202 and fixed by embedding with epoxy resin. The inertial sensors 220, 222 may be configured to detect vertical acceleration due to vertical movement of the forming unit 202 and to calculate the position of the forming unit 202 relative to the sealing unit 204 during the (entire) movement, e.g. in real time.

[0095] Additionally or alternatively, the motion detector 22 may comprise one or more magnets 226 arranged on the body 206 of the forming unit 202 and one or more magnetometers 224, e.g. Hall sensors, arranged on the sealing unit 204. For example, the magnetometers 224 and the magnets 226 may be fixed to the respective sealing unit 204, forming unit 202 on a surface facing the respective forming unit 202, sealing unit 204.

[0096] The magnetometer 224 may be configured to detect changes in the magnetic field due to vertical movement of the magnet 226 fixed to the forming unit 202 and to calculate the position of the forming unit 202 during (the entire) operation, e.g. in real time, i.e. the motion profile of the forming unit 202 during the molding operation can be measured with high accuracy.

[0097] In one or more embodiments, to supply power to the movable members 2, the forming assembly 7, e.g., packaging assembly, may include a power supply 4, e.g., an electrical pulse generator or a transformer, as described above. The power supply 4 is disposed on the track 1 and is electrically coupleable, e.g., temporarily, to one or more movable members 2 and capable of supplying power thereto. The movable members 2 may be configured to be electrically coupled to the power supply 4 in a predetermined power supply area.

[0098] The invention allows the relative movement of one or more elements 20, 21 of the movable part 2 to be measured without contact.

[0099] One or more embodiments may relate to a method for calculating the movement of the movable member 2 and / or the first and / or second element 20, 21. The method comprises: providing a linear motor system according to one or more embodiments as described above; - detecting the movement of the mobile member 2, the first and / or second elements 20, 21 by one or more motion detectors 22, - transmitting an operation signal M by the operation detector 22, - calculating the movement of the mobile member 2, the first and / or second element 20, 21, the method may comprise calculating as a function of the actuation signal M, - the position of the movable member (2) relative to the track (1), and / or - the position of the second element (21) relative to the first element (20), and / or - a vibration pattern of the moving member (2) showing its coupling to the track (1); Equipped with.

[0100] The method may include electrically coupling, for example temporarily, a power supply 4 to the at least one moveable member 2 and supplying power to the moveable member 2 .

[0101] The method comprises, for a motion detector 22 attached to the first or second element 20, 21: - calculating the acceleration and angular velocity of the first or second element 21 as a function of the actuation signal M, - Calculating the position of the first or second element 21 as a function of the calculated, e.g. measured and filtered, acceleration and angular velocity. The present invention may also include the following.

[0102] The method further comprises: -1000, receiving an operating signal M including a first signal M1 indicative of an acceleration of the first or second element 21; - 1002, receiving an operating signal M including a second signal M2 indicative of an angular velocity of the first or second element 21; 1004, calculating the orientation of the first or second element 21 as a function of the second signal M2 and an initial estimate of the orientation of the first or second element 21; 1006, calculating the acceleration of the first or second element 21 as a function of the first signal M1, the calculated direction and the initial reference frame; -1008, calculate the gravitational acceleration correction as a function of the calculated direction, -1010, sum the calculated acceleration and gravity acceleration correction, -1012, calculating a position and / or a velocity of the first or second element 21 as a function of said sum and a predetermined initial position and / or a predetermined initial velocity. The present invention may also include the following.

[0103] The method comprises: - a motion sensor 220 for receiving motion signals M from a plurality of motion detectors 22 spaced apart from one another on the movable member 2; - calculating the respective acceleration as a function of the operating signal M, - checking whether the operating signals M differ by more than a predetermined amount, for example in the case of acceleration, if they differ by more than an acceleration threshold which indicates a malfunction of the mobile member 2 sliding along the track 1, The present invention may also include the following.

[0104] The method may comprise fixing the motion detector 22 to the moveable member 2 by embedding the motion detector 22 in epoxy resin.

[0105] The method may further comprise the steps of: - at least one magnet 226 is arranged on either the first element 20 or the second element 21; - a magnetometer 224, preferably a Hall sensor, is arranged on the other of the first element 20 or the second element 21; - calculating the position of the second element 21 relative to the first element as a function of the operating signals M, including a third signal M3 representative of the change in the magnetic field due to the movement of the magnet 226; The present invention may also include the following.

[0106] The method comprises: - providing a synchronization device 3, - sending a synchronization signal S, - detecting a synchronization signal S by a synchronization sensor 25; - calculating the position of the mobile element 2 relative to the trajectory 1 and / or the position of the second element 21 relative to the first element as a function of the synchronization signal S, The present invention may also include the following.

[0107] The method may, for example, comprise the steps of: - transmitting the calculated position and / or velocity and / or acceleration; - monitoring the movement of the elements 20, 21 of the movable mass; and / or Identifying faults or errors as a function of the calculated position and / or velocity and / or acceleration, The present invention may also include the following.

[0108] If a fault or error is identified, the method may include generating an alarm signal indicating the detected error and / or interrupting operation of the moveable member 2.

Claims

1. An orbit (1), At least one movable member (2) coupled to the orbit (1) and configured to move along the orbit (1), and the at least one movable member (2) includes A first element (20), A second element (21) movable relative to the first element (20), At least one magnet (226) configured to transmit an operation signal (M) and disposed on one of the first element (20) or the second element (21), and at least one magnetometer (224) disposed on the other of the first element (20) or the second element (21), and at least one motion detector (22) comprising Comprising A processing unit (5, 23) configured to calculate the movement of the second element (21) relative to the first element (20) as a function of the operation signal (M) received from the motion detector (22), A linear motor system comprising

2. The movement signal (M) indicates a magnetic field in the at least one magnetometer (224), and the detected magnetic field changes as a function of the movement of the first element (20) and / or the second element (21). The linear motor system according to claim 1.

3. The at least one magnetometer (224) is disposed on the first element (20), and the at least one magnet (226) is disposed on the second element (21). The linear motor system according to claim 1 or claim 2.

4. The motion detector (22) comprises a plurality of magnetometers (224). The linear motor system according to claim 1.

5. The plurality of magnetometers (224) are arranged in a cross shape. The linear motor system according to claim 4.

6. The magnetometer (224a) at the center of the cross has higher sensitivity than other magnetometers (224b) in the motion detector (22). The linear motor system according to claim 5.

7. The at least one magnet (224) is aligned with the magnetometer (224) at the center of the cross with respect to an axis (X1) parallel to the direction (X) of the relative movement of the second element (21) with respect to the first element (20). The linear motor system according to claim 5.

8. The at least one magnetometer (204) comprises a Hall sensor and / or an anisotropic magnetoresistive sensor. The linear motor system according to claim 1.

9. further comprising a synchronization device (3) configured to transmit a synchronization signal (S), wherein the at least one movable member (2) comprises a synchronization sensor (25) configured to detect the synchronization signal (S), wherein the processing unit (5, 23) is configured to calculate the movement of the second element (21) relative to the first element (20) as a function of the synchronization signal (S), The linear motor system according to claim 1.

10. wherein the synchronization device (3) comprises an optical transmitter configured to transmit an optical synchronization signal (S), and the synchronization sensor (25) comprises an optical sensor configured to detect the optical synchronization signal (S); or wherein the synchronization device (3) comprises a power supply device (4) configured to supply power to the at least one movable member (2), the at least one movable member (2) comprises a power supply module (24) configured to receive power from the power supply device (4), and the synchronization sensor (25) is configured to detect a synchronization signal (S) indicative of power transmission between the power supply device (4) and the power supply module (24). The linear motor system according to claim 9.

11. wherein the at least one motion detector (22) is embedded in an epoxy resin and fixed to the movable member (2), The linear motor system according to claim 1.

12. a molding assembly (7) configured to form a plurality of packages (80), the molding assembly (7) comprising a pair of endless tracks (1), a pair of movable members (2), each movable member (2) being movably coupled to a corresponding one of the tracks (1) and being movable periodically along the one track (1), each movable member (2) of the pair of movable members (2) comprises a first element (20), a second element (21) movable relative to the first element (20), and a forming unit (202) movable periodically and configured to form the package (80), and comprising At least one of the pair of movable members (2) includes at least one motion detector (22) configured to transmit a motion signal (M), and the motion detector (22) includes at least one magnet (226) disposed on one of the first element (20) or the second element (21), and at least one magnetometer (224) disposed on the other of the first element (20) or the second element (21). The forming assembly (7) includes a processing unit (5, 23) configured to calculate the movement of the second element (21) relative to the first element (20) as a function of the motion signal (M) received from the motion detector (22). Forming assembly (7).

13. A packaging assembly configured to form and seal a plurality of packs (80) containing a pourable product starting from a tube (8) of packaging material, the packaging assembly including a pair of endless tracks (1) along which the tube (8) is fed in a linear forward direction (X). Each of the pair of movable members (2) includes a respective forming unit (202) and a respective sealing unit (204) linearly movable in a lateral direction with respect to the forward direction (X) and toward the tube (8) so as to periodically cooperate in contact with successive tube portions (82) to respectively form and seal at least the corresponding pack portions of the respective packs (80). The forming assembly (7) according to claim 12.

14. The first element (20) and / or the second element (21) includes the body (200) of the movable member (2), one or more components (206, 207, 208, 210) of the forming unit (202), and / or one or more components (204, 212) of the sealing unit (204). The forming assembly (7) according to claim 12.

15. A method of calculating the movement of a second element (21) relative to a first element (20) of a movable member (2) in a linear motor system, the method including:[[]] Providing a linear motor system according to claim 1. Transmitting a motion signal (M) by at least one motion detector (22). Calculating the movement of the second element (21) and / or the first element (20) as a function of the motion signal (M) received from the motion detector (22). A method including the above.

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