Movement control device for controlling the movement of a movable member of a manufacturing machine for manufacturing plastic containers

Abstract

The present invention relates to a manufacturing machine (1) for manufacturing plastic containers, the manufacturing machine comprising: a frame (2), the frame having a cam path (6), the cam path having a cam (61) and a counter-cam (62); a movable component (3) movable relative to the frame (2), the movable component carrying a roller (7), the roller cooperating with the cam path (6) to ensure the movement of the movable component (3), the manufacturing machine (1) also comprising a control device (4) for controlling the movement of the movable component (3), characterized in that the counter-cam (62) has at least one movable part (63) movable relative to the frame (2), the control device (4) being integrated with a distance sensor (11), the distance sensor continuously measuring the distance of the movable part (63) of the counter-cam (62) relative to a relevant reference point of the frame (2).

Description

Technical Field

[0001] The field of the invention is that of the design and manufacture of manufacturing machines for manufacturing plastic containers.

[0002] More particularly, the present invention relates to motion control devices for controlling the movement of movable components of manufacturing machines. Background Art

[0003] Plastic containers are obtained from preforms which are blown or stretch-blow deformed to obtain their final shape.

[0004] In particular, the preform is heated until the constituent materials reach the glass transition temperature, at which point the plastic becomes ductile enough to be drawn without being scratched.

[0005] The formed containers are then transported to a processing unit for decontamination, filling, sealing and labeling.

[0006] The handling device generally has at least one movable member movable relative to a frame of the manufacturing machine, and the movable member is generally adapted to come into contact with a portion of the container, or at least to move into proximity therewith.

[0007] Some treatment devices process with compressed air. This is particularly the case with blowing devices, which inject air into the preform, drawing the material it is made of.

[0008] The air is injected into the preform by a blow tube which is movable relative to the mold in which the preform to be blown is received.

[0009] However, the mould has at least one movable part which allows the preform to be inserted and the blown container, ie the shaped container, to be output.

[0010] The movement of the movable member is generally carried out by the cooperation of a cam path and a roller.

[0011] In order for the manufacture of the container to proceed smoothly, the mold closing and the blow tube positioning should be controlled.

[0012] The first control technique is listening.

[0013] This technology allows operators to carefully detect abnormal noises in manufacturing machinery and, if necessary, stop the machine to perform maintenance.

[0014] However, this technique has one major drawback.

[0015] In fact, noise discrimination is an inherent ability of everyone, but it requires very experienced operators. Therefore, for the same obvious noise, one operator may decide to stop the machine operation, while another operator keeps the production cycle going.

[0016] In addition, it is difficult to determine which faulty component is making the abnormal noise by listening alone.

[0017] In addition, when operators hear unusual noises, it means that the machine is degraded and must be shut down for repair work. In other words, when a part breaks or is nearly broken on a machine, the cost of replacing the part is higher than the cost of repairing it (obviously, when the part can still be repaired before it breaks).

[0018] That is, the manufacturing machinery is no longer functional and therefore has no benefit to the owner.

[0019] To remedy this shortcoming, a second technology was developed.

[0020] This second technology is particularly aimed at predictive technical maintenance, which is less expensive than curative technical maintenance.

[0021] In fact, predictive maintenance technology can limit the downtime of machinery, thereby reducing the costs associated with machinery being unavailable.

[0022] This second technique consists in using a vibration sensor positioned on the machine. The signal generated by the sensor is thus processed to carry out a vibration analysis to detect the reproducibility of the signal corresponding to a normal cycle. This signal analysis is therefore complex and places a heavy processing burden on the information unit that manufactures the machine.

[0023] Thus, when the signal is analyzed and an anomaly is detected relative to the normal signal, the operator can predict the damage of a component of the machinery and plan a technical maintenance phase.

[0024] While this second technique is satisfactory in terms of machine downtime, it is not without its drawbacks.

[0025] In practice, vibration sensors are costly.

[0026] Furthermore, the container manufacturing machines are large-sized machines having several connected processing devices.

[0027] Therefore, vibrations in one processing device may affect another processing device.

[0028] Therefore, when performing vibration analysis, the relevant signals must be cleaned up, that is, the "noise" that degrades the signal quality must be removed.

[0029] In other words, disturbing vibrations associated with an adjacent device are damped to obtain a usable signal for the component that has to be controlled.

[0030] This cleaning is both costly and time consuming, so that this second technique, while time consuming, is less accurate if the processing time is shortened in order to ensure production schedules.

[0031] The third technique is to use common sensors. The cost of such sensors is lower than that of vibration sensors, but they cannot be applied to predictive maintenance.

[0032] In fact, these sensors detect whether the moving parts are well positioned or mispositioned. If mispositioning is detected, it means it is too late and the technical maintenance to be performed is not predictive technical maintenance, but curative technical maintenance.

[0033] This third technique thus automates the first technique, but still has its major drawbacks. Summary of the invention

[0034] The present invention is particularly intended to remedy the deficiencies of the prior art.

[0035] More precisely, the present invention aims to implement control over machinery to avoid excessive damage and implement predictive technical maintenance.

[0036] The invention also aims at predicting the risk of failure of a manufacturing machine.

[0037] The invention is also intended to allow tracking of manufacturing modules during manufacturing.

[0038] These objects and other objects described below are achieved by means of the present invention, which relates to a manufacturing machine for manufacturing plastic containers, which has:

[0039] - a carrier having a cam path with a cam and a counter-cam;

[0040] - a movable member movable relative to the seat frame, the movable member carrying rollers, the rollers cooperating with the cam path to ensure the movement of the movable member,

[0041] The manufacturing machine also has a control device that controls the movement of the movable components.

[0042] Characterized in that the counter-cam has at least one active part that is movable relative to the frame, and that the control device integrates a distance sensor that continuously measures the distance of the active part of the counter-cam relative to a relevant reference point of the frame

[0043] And it is characterized in that the manufacturing machine has an information unit connected to the distance sensor, which is parameterized to identify the movement change of the active part of the counter-cam relative to the predetermined movement for each cycle, compare the movement change with the allowable change range, and send a warning signal when the movement change exceeds the allowable change range.

[0044] Continuous measurement of the distance of the active part of the counter-cam relative to the relevant reference point of the seat frame makes it possible to detect deviations in the movement of the active member.

[0045] Such deviations are generally a symptom of impending failure of a component of the manufacturing machinery and can therefore be corrected to eliminate the detected deviation by replacing the component or, preferably, repairing it.

[0046] However, if the deviation remains slight and constant, it can be determined that there is a simple misalignment of the production machine or that technical maintenance is necessary, such as lubrication of a component, which misalignment or lubrication can be performed after a shutdown in order to perform technical maintenance on the production machine.

[0047] The use of distance sensors allows obtaining a noise-free signal which is easier to utilize than signals obtained with prior art techniques such as vibration sensors.

[0048] Advantageously, the sensor is an inductive sensor.

[0049] The use of inductive sensors can remove certain constraints associated with the operation of manufacturing machinery.

[0050] In fact, mechanical lubrication, dust or humidity do not affect the use of inductive sensors.

[0051] In other embodiments, the sensor is an optical sensor.

[0052] This sensor precisely measures the movement of the active part of the counter-cam relative to the carrier.

[0053] In particular, according to the first embodiment, the movable portion of the counter-cam has a through hole, and the sensor is fixed to the mount and positioned in the through hole.

[0054] This arrangement allows the control device to be compact, in particular to be accommodated in an existing but, for example, unused space.

[0055] Furthermore, positioning the sensor in a perforation protects the sensor from foreign matter (lubricant, dust, etc.) and from collisions, for example with another movable or fixed component of the manufacturing machine.

[0056] In particular, according to the second embodiment, the sensor is fixed to the movable part of the counter-cam.

[0057] This configuration also makes it possible to adapt precisely the position of the active part of the counter-cam relative to the seat frame.

[0058] Furthermore, when the sensor is attached to the movable part of the counter-cam, it reliably detects movements transmitted by the roller to the movable part, even movements of small magnitude.

[0059] The invention also relates to a method for detecting a risk of failure of movement of a movable component of a container manufacturing machine relative to a support according to any one of the preceding claims,

[0060] Characterized in that, for each manufacturing cycle, the detection method has the following stages:

[0061] - Establishment of the distance curve between the active part of the counter-cam and the relevant reference points of the frame;

[0062] - identifying the degree of deviation between the established distance curve and the predetermined distance curve;

[0063] - compare the deviation with the permissible variation range;

[0064] - If the deviation exceeds the permissible variation range, a warning signal is issued.

[0065] This method can implement a predictive maintenance phase, because the adjustment or maintenance of the machine can be performed when the manufacturing machine is scheduled to stop. In addition, the method can check the effect of the adjustment and / or maintenance performed.

[0066] Therefore, the number of downtimes for technical maintenance is reduced, and the technical maintenance costs are lower compared to the costs of curative technical maintenance.

[0067] Advantageously, the method also comprises a recognition phase for recognizing the recurrence of the degree of deviation, during which the degree of deviation of the period being analysed is compared with a series of degrees of deviation of preceding periods in order to detect increasingly greater degrees of deviation.

[0068] The identification of the recurrence of the offset can exclude the point offset of the movement of the active part of the counter-cam.

[0069] In fact, the presence of a defective container may cause a deviation in the movement of the counter-cam over a specific period without requiring any particular technical maintenance.

[0070] According to one embodiment, the warning signal includes an acoustic effect or a message transmitted to a production operator.

[0071] This sound effect or message can be recognized by an operator who is not located near the machine.

[0072] The operator is therefore in the vicinity of the machine that emits the signal, monitoring its operation and even carrying out a technical maintenance phase if necessary.

[0073] According to another embodiment, the warning signal comprises a shutdown command for the production machine.

[0074] This instruction can make manufacturing machinery safe and avoid major damage to the machinery. In other words, before it is too late, before the damage of a component completely damages the machine and requires corrective maintenance, the downtime can be carried out for predictive maintenance.

[0075] In other embodiments, the warning may be a shutdown command for the manufacturing machine combined with an audible effect or information transmission to the production operator. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Other features and advantages of the present invention will become apparent from the following description of a preferred embodiment of the invention given as an illustrative and non-limiting example with reference to the accompanying drawings, which are as follows:

[0077] Figure 1 is a partial detail view of a manufacturing machine according to a first embodiment of the present invention;

[0078] Figure 2 is a partial detail view of a manufacturing machine according to a second embodiment of the present invention;

[0079] Figure 3 is a flow chart of the movement control of a movable component of the manufacturing machine of the present invention over a plurality of consecutive cycles under normal working conditions;

[0080] Figure 4 It is a flow chart of the movement control of a movable component of the manufacturing machine of the present invention under abnormal working conditions over multiple consecutive cycles. DETAILED DESCRIPTION

[0081] Figure 1 A manufacturing machine 1 for manufacturing plastic containers according to the invention is shown schematically.

[0082] This manufacturing machine 1 has:

[0083] - a seat frame 2;

[0084] - a movable member movable relative to the seat frame 2;

[0085] - a movement control device 4 of the movable member 3;

[0086] -Information unit 5.

[0087] like Figure 1 and 2 As shown, the seat frame 2 has a cam path 6, which has:

[0088] - Cam 61;

[0089] - Counter cam 62.

[0090] As will be described later, the cam path 6 can control the movement of the movable member 3 .

[0091] To this end, the movable member 3 carries a roller 7 which cooperates with the cam path 6 .

[0092] More precisely, roller 7 comes into contact with cam 61 and then, at the end of cam path 6 , with counter-cam 62 .

[0093] In order to control the mobile member 3 to move well, the counter-cam has at least one mobile portion 63 that is mobile relative to the frame 2 .

[0094] according to Figure 1 In the first embodiment shown, the movable portion 63 and the counter cam 62 are formed as a single piece. In other words, the counter cam 62 is integrally movable around the first pivot 8 relative to the seat frame 2.

[0095] according to Figure 2 In the second embodiment shown, the mobile part 63 is formed by one end of the counter-cam 62. Thus, the first part 62a of the counter-cam 62 is fixed relative to the frame 2, while the mobile part 63 is pivotable about the second pivot 9 relative to the first part and thus to the frame 2.

[0096] In this second embodiment, the mobile part 63 is held in the guided position by the resetting means 10 which tend to push the mobile part 63 into the extension of the first portion of the counter-cam 62. The first embodiment may also be provided with a resetting means.

[0097] In other words, in the guide position, the active portion 63 has a guide surface for guiding the roller 7 , which is tangential to the guide surface of the first portion of the counter-cam 62 .

[0098] The movement control device 4 of the mobile member 3 integrates a distance sensor 11 which continuously measures the distance of the mobile portion 63 of the counter-cam 62 relative to a relevant reference point of the frame 2 .

[0099] According to a first embodiment, the sensor 11 is an inductive sensor.

[0100] According to a second embodiment, the sensor 11 is an optical sensor.

[0101] Referring to the first embodiment Figure 1 , the sensor 11 is fixedly connected to the movable part 63 of the counter cam 62.

[0102] exist Figure 1 In the embodiment shown, the sensor 11 is fixed to the counter-cam 62 , since the counter-cam 62 and the mobile part 63 are a single piece.

[0103] Therefore, the sensor 11 follows the movement of the counter cam 62 and continuously measures the separation distance of the mount 2 .

[0104] Here, therefore, the reference point of the support 2 is mobile relative to the sensor, since the rotation of the counter-cam 62 and the fixation of the sensor 11 on the counter-cam 62 cause the sensor 11 to perform a circular movement.

[0105] Referring to the second embodiment Figure 2 , the sensor 11 is fixedly connected to the seat frame 2 and accommodated in the movable part 63 of the counter cam 62.

[0106] More precisely, the movable portion 63 of the counter-cam 62 has a through hole 621 in which the sensor 11 is fixed to the mount 2 and positioned.

[0107] Here, therefore, the reference point of the mount 2 is formed by the sensor 11 itself, which therefore continuously measures its distance relative to the edge of the perforation 621 .

[0108] In operation, when the roller 7 supports and moves the movable part 63, the sensor 11 is separated from the wall of the perforation 621 and continuously stores the separation distance. Therefore, when the roller 7 no longer exerts a force on the counter-cam 62, the movable part 63 is reset to its starting position, that is, reset to the extension of the first part of the counter-cam 62.

[0109] The information unit 5 is connected to the distance sensor 11 and is parameterized for determining the displacement of the movable component 3 by the method described below.

[0110] More precisely, the information unit 5 is parameterized to determine, for each cycle, the variation in movement of the active portion 63 of the counter-cam 62 relative to a predetermined movement, to compare said variation with an admissible variation range and to generate a warning when said variation in movement exceeds the admissible variation range.

[0111] The method is a method for detecting the risk of a movement failure of a movable member 3 relative to a frame 2 of a manufacturing machine 1 for manufacturing containers.

[0112] For each manufacturing cycle, the inspection method has the following stages:

[0113] - establishing a distance curve, for example as a function of time, between the active portion 63 of the counter-cam 62 and a relevant reference point of the frame 2;

[0114] - identifying the degree of deviation between the established distance curve and the predetermined distance curve;

[0115] - compare the deviation with the permissible variation range;

[0116] - If the deviation exceeds the permissible variation range, a warning signal is issued.

[0117] Figure 3 and 4A series of distance curves showing the distances between the active portion 63 of the counter-cam 62 and the relevant reference points of the frame 2 .

[0118] More precisely, Figure 3 and 4 The movements D1 , D2 , D3 , D4 , D5 of five different movable members 3 on the same cam path 6 are shown.

[0119] exist Figure 3 In the embodiment, all movements D1, D2, D3, D4, D5 are normal, ie no deviation can be detected, and these curves in particular form a predetermined distance curve.

[0120] On the contrary, Figure 4 Above, moves D2 and D3 have anomalies.

[0121] In fact, compared with Figure 3 As shown in the curves D2 and D3, the signal transmitted by the sensor 11 has a large variation, which indicates the degree of deviation in the movement of the movable member 3.

[0122] Therefore, the information unit 5 must transmit this information to the production operator.

[0123] For this purpose, the machine 1 has a signaling system 12 , for example with a display screen, a loudspeaker and / or a light signaling device.

[0124] Therefore, when the information unit 5 detects the deviation, the information unit controls the signal display system 12 to send a warning signal to the production operator.

[0125] For this purpose, the warning signal consists in transmitting an acoustic effect to the production operator via a loudspeaker, if necessary connected to a light signal, or in transmitting information to the production operator via a display screen, for example.

[0126] For greater precision, the method also comprises a recognition phase for recognizing the recurrence of the degree of deviation, during which the degree of deviation of the period being analysed is compared with a series of degrees of deviation of preceding periods in order to detect increasing degrees of deviation.

[0127] This makes it possible in particular to check that the abnormalities determined on the curves D1 , D2 , D3 , D4 , D5 are not isolated cases that occur temporarily, for example defective containers.

[0128] In the case of a large deviation, for example, the warning signal includes a shutdown command for the production machine 1 .

[0129] This makes it possible in particular to avoid any risk of irreversible damage to the production machine 1 .

[0130] With the aid of the manufacturing machine 1 and the detection method, possible abnormal conditions of the manufacturing machine 1 can be tracked, and predictive technical maintenance can be performed before the manufacturing machine 1 suffers major damage.

[0131] Additionally, the detection method can track changes in the anomaly and, optionally, determine the cause of the anomaly.

Claims

1. A manufacturing machine for manufacturing plastic containers (1), the manufacturing machine having: - a seat frame (2) having a cam path (6) with a cam (61) and a counter-cam (62); - a movable member (3) movable relative to the frame (2), the movable member carrying a roller (7), the roller cooperating with the cam path (6) to ensure the movement of the movable member (3), the manufacturing machine (1) also having a control device (4) for controlling the movement of the movable member (3), It is characterized in that The counter cam (62) has at least one movable part (63) movable relative to the seat frame (2), and the control device (4) is integrated with a distance sensor (11), which continuously measures the distance of the movable part (63) of the counter cam (62) relative to the relevant reference point of the seat frame (2); and the manufacturing machine (1) has an information unit (5) connected to the distance sensor (11), and the information unit (5) is parameterized to identify the movement change of the movable part (63) of the counter cam (62) relative to the predetermined movement for each cycle, compare the movement change with the allowable change range, and issue a warning signal when the movement change exceeds the allowable change range.

2. The manufacturing machine (1) according to claim 1, characterized in that The distance sensor (11) is an inductive sensor.

3. The manufacturing machine (1) according to claim 1, characterized in that The distance sensor (11) is an optical sensor.

4. The manufacturing machine (1) according to any one of claims 1 to 3, characterized in that The movable portion (63) of the counter cam (62) has a through hole (621), and the distance sensor (11) is fixed on the seat frame (2) and positioned in the through hole (621).

5. The manufacturing machine (1) according to any one of claims 1 to 3, characterized in that The distance sensor (11) is fixedly connected to the movable part (63) of the counter cam (62).

6. Method for detecting a risk of a movement failure of a movable component (3) relative to a support (2) of a manufacturing machine (1) for manufacturing plastic containers according to any one of the preceding claims, It is characterized in that For each manufacturing cycle, the inspection method has the following stages: - Establishing a distance curve between the active part (63) of the counter-cam (62) and the relevant reference points of the seat frame (2); - identifying the degree of deviation between the established distance curve and the predetermined distance curve; - compare the deviation with the permissible variation range; - If the deviation exceeds the permissible variation range, a warning signal is issued.

7. The detection method according to claim 6, characterized in that: The detection method also has a recognition phase for identifying recurrences of excursions, in which the excursion of the analyzed period is compared with a series of excursions of preceding periods in order to detect increasingly larger excursions.

8. The detection method according to claim 6 or 7, characterized in that: The warning signal includes transmitting information to the production operator through an audible effect or a display screen.

9. The detection method according to claim 6 or 7, characterized in that: Warning signals include stop commands for manufacturing machinery.

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