Blow-dry envelope cleaning machine

Abstract

A blow-cleaning machine for envelopes (100), comprising: - a frame (10), - a rotating platform (20), arranged to receive and convey a plurality of envelopes (100) to be cleaned, - at least one blow-cleaning nozzle (30), mounted on the rotating platform (20) and arranged to blow-clean at least one envelope, - a fixed supply connection (40), fixedly mounted on the frame (10), characterized in that the cleaning machine comprises at least one rotary distributor (50) arranged between the fixed connection and said at least one blow-cleaning nozzle (30), comprising a fixed shaft (51) with a single distribution window (513) arranged to supply said at least one blow-cleaning nozzle (30) with blow-cleaning air only over a predetermined angular blow-cleaning sector (Saf). Figure for the abbreviation: Fig. 1

Description

Title of the invention: Blow-drying envelope cleaning machine. Technical field of the invention

[0001] The present invention relates generally to machines for cleaning casings used to form containers or intermediates in the manufacture of containers. In particular, the casings may be plastic preforms that must be cleaned before being transformed into containers for food liquids. Prior art

[0002] In the prior art of envelope cleaning machines by blowing, it is known, for example, from document WO2010052416A1, to provide blowing nozzles mounted movably on a rotating platform and capable of engaging envelopes received by the rotating platform in order to clean them. However, this system can present several drawbacks. In particular, compressed air consumption is significant because any impurities present in the envelopes are expelled by blowing air, and the blowing nozzles are continuously supplied. Furthermore, it can also be noted that the structure is complex, with pressurized parts sliding relative to one another. Such complexity can generate particles due to frictional wear of the sliding joints, and high design, manufacturing, and maintenance costs. Description of the invention

[0003] One object of the present invention is to address the disadvantages of the prior art mentioned above and in particular, first of all, to propose a blow cleaning machine which makes it possible to save compressed air, while remaining reliable and robust.

[0004] To this end, a first aspect of the invention relates to a blow-cleaning machine for casings forming containers or intermediates in the manufacture of containers, comprising: - a building, - a rotating platform, mounted pivoting on the frame and arranged to receive and convey a plurality of envelopes to be cleaned between an entry position and an exit position, - at least one blow nozzle, mounted on the rotating platform and arranged to clean by blowing at least one envelope received and conveyed by the rotating platform between the entry position and the exit position, - a fixed power supply connection, permanently mounted on the frame and arranged to be connected to a blowing air source, characterized in that the cleaning machine comprises at least one rotating pneumatic distributor arranged between the fixed fitting and said at least one blowing nozzle, comprising a fixed shaft with a single distribution window arranged to supply said at least one blowing nozzle with blowing air only over a predetermined angular blowing sector between the inlet position and the outlet position.

[0005] The cleaning machine according to the above embodiment has a single distribution window, which reduces the compressed air supply time to each blow nozzle. In other words, the blow nozzles are only supplied with air for a portion of the rotary table's revolution. It is therefore possible to supply the blow nozzle only for the period of time necessary to ensure sufficient cleaning. Compared to supplying air for the entire revolution of the rotary table, a significant amount of air is saved. It should be noted that each blow nozzle can also be called a cannula, due to its slender shape which allows it to be inserted into the casings.It can also be noted that each blow nozzle has a single supply circuit (going from the rotating distributor to the blow nozzle), the blow nozzle having a single blow orifice forming a jet, or several blow orifices fed simultaneously forming a plurality of jets.

[0006] According to one embodiment, the angular blowing sector is: - less than a defined angular sector between the entry and exit positions of the turntable, and / or - within a range of 120° to 210° and preferably within a range of 140 to 180°. For example, an angular sector of approximately 150° can be provided, which reduces air consumption by more than half, compared to a prior art cleaning machine which supplies the blow nozzles over 360° (i.e. continuously).

[0007] According to one embodiment, the rotary pneumatic distributor comprises: - a rotating hub mounted on the rotating plate, - a fixed shaft integral with the frame, and the fixed shaft includes a fixed supply passage with a downstream outlet to the rotating hub, the downstream outlet forming the distribution window and extending along or over the angular blowing sector. The structure is simple, and the angular blowing sector is defined by the tangential length of the distribution window.

[0008] According to one embodiment, the rotating hub includes at least one rotating feed passage comprising a rotating outlet connected with said at least one blow nozzle.

[0009] According to one embodiment, the cleaning machine comprises a plurality of blow nozzles, in which the rotating hub comprises a plurality of rotating feed passages, each comprising a rotating outlet connected with one of the blow nozzles.

[0010] According to one embodiment, said at least one rotating supply passage has a rotating inlet arranged opposite the fixed shaft, in an axial zone including the fixed outlet. It is the passage of the rotating inlet opposite the distribution window that will allow the supply of compressed air to the blow nozzle.

[0011] According to one embodiment, the rotating pneumatic distributor includes sealing means arranged axially on either side of the downstream (fixed) outlet and / or the rotating inlet.

[0012] According to one embodiment, the sealing means comprise at least one seal, such as an O-ring, and preferably a composite seal comprising an O-ring housed in a groove formed in one of the fixed shafts or rotating hubs, combined with a flat polymer seal housed in the groove between the O-ring and the other of the fixed shaft or rotating hub. Such an assembly allows for the use of a flat seal that meets, for example, food-grade standards, while ensuring the elastic contact force provided by the O-ring.

[0013] According to one embodiment, the rotary distributor comprises at least one guide bearing and a decompression orifice formed in the rotating hub and arranged between the sealing means and the guide bearing. Such a decompression orifice typically vents the internal space delimited by the fixed shaft, the rotating hub, the sealing ring, and the bearing. This prevents the bearing, its cage, or its dust covers from being pressurized.

[0014] According to one embodiment, the cleaning machine comprises at least one flexible tube connecting, preferably directly, said at least one rotating outlet with said at least one blow nozzle. A flexible tube allows the rotating hub (fixed relative to the turntable) to be connected directly to the blow nozzle or cannula (movable relative to the turntable) without any sliding parts or pistons, thus eliminating the need for seals and complex mechanisms.

[0015] According to one embodiment, said at least one blow nozzle is mounted movable relative to the rotating platform so as to be able to engage with the casing, at least over a portion of the angular blowing sector. In other words, the cleaning machine is designed so that the blow nozzle(s) are / are aligned once placed in the casing.

[0016] According to one embodiment, the cleaning machine includes a cam track engaged with at least one cam follower arranged to cause the relative movement of the blow nozzle with respect to the rotating plate.

[0017] According to one embodiment, said at least one blow nozzle is mounted in a sliding connection relative to the rotating plate.

[0018] According to one embodiment, the blowing sector is defined so that the blowing nozzle is supplied when the blowing nozzle is engaged in the envelope.

[0019] According to one embodiment, the cleaning machine includes suction means arranged to collect residues blown by the blowing nozzle.

[0020] According to one embodiment, the envelopes are preforms of plastic containers. Such preforms are intended to be transformed into final containers by a blow molding operation.

[0021] According to one embodiment, the rotary distributor includes at least one spacer foot. Such a spacer foot allows the rotating hub to be positioned at the height of the connection to the blow nozzles in order to limit the length of the flexible hoses. Friction, pinching, and pressure losses are reduced.

[0022] According to one embodiment, a union fitting or nipple (with two male outlets), or a sleeve (with two female outlets), or an intermediate fitting is provided between the fixed shaft and the fixed supply fitting. This allows the angular position of the fixed shaft and the distribution window relative to the frame of the cleaning machine to be adjusted, thereby setting the angular position of the blowing sector.

[0023] According to one embodiment, the cleaning machine includes a force absorption and positioning device arranged between the fixed shaft and the frame. This allows the position of the fixed shaft to be adjusted, typically along its axial direction and / or, more importantly, its angular orientation. Internal friction forces within the rotating distributor are also absorbed.

[0024] According to one embodiment, the rotary distributor includes reversible fixing means allowing one or more wedges or shims or blocks to be reversibly fixed in the distribution window, so as to adjust the extent of the angular blowing sector. Description of the figures

[0025] Other features and advantages of the present invention will become more apparent upon reading the following detailed description of an embodiment of the invention given by way of non-limiting example and illustrated by the accompanying drawings, in which:

[0026] [Fig. 1] represents a schematic and side view of a cleaning machine comprising a rotating platform receiving envelopes to be cleaned by blowing and a rotating distributor mounted on the rotating platform;

[0027] [Fig.2] represents a cross-sectional view of the rotary distributor of the machine cleaning of the [Fig.l];

[0028] [Fig.3] represents a top view of the rotating distributor of the cleaning machine of the [Fig.1]. Detailed description of implementation method(s)

[0029] Figure 1 represents a blow-cleaning machine for cleaning casings 100 forming containers or container manufacturing intermediates, comprising: - a frame 10, - a rotating platform 20, mounted pivoting on the frame 10 and arranged to receive and convey a plurality of envelopes 100 to be cleaned, between an entry position and an exit position, - a plurality of blow nozzles 30, mounted on the rotating platform 20 and arranged to clean by blowing the envelopes 100 received and conveyed by the rotating platform 20, - a fixed supply fitting 40, fixedly mounted on the frame 10 and arranged to be connected to a supply air source (not shown), - a rotating distributor 50.

[0030] Generally speaking, the cleaning machine is a blow-cleaning machine that receives 100 envelopes at the input, cleans them by blowing, and returns them to the production line at the output. The 100 envelopes are conveyed by the cleaning machine during the cleaning cycle.

[0031] The envelopes 100 are typically containers, containers intended to hold food products, and in this example are preforms for water bottles. However, other uses or applications for the envelopes 100 can be envisaged.

[0032] The frame 10 is shown schematically; its function is to support the constituent elements of the cleaning machine. A metal frame, either welded or composed of elements attached to each other, such as aluminum cross members or profiles, may be provided.

[0033] The turntable 20 is mounted on the frame 10 by means of a pivot joint, so that it can pivot / rotate under the impulse of an electric motor 21, mounted here on the frame 10 perpendicular to the axis of rotation of the turntable 20, via a reduction gear. A rotational speed of between 20 and 40 revolutions per minute can typically be applied to the turntable 20.

[0034] The turntable 20 has indentations for receiving envelopes 100, and additional supports can be provided to allow the envelopes 100 to be received and positioned precisely. Means for loading and unloading the envelopes 100 onto the turntable 20 can also be provided.

[0035] On the central part of the rotating platform, a spacer foot 58 can be provided, mounted on the rotating platform 20 and receiving a rotating hub 52. A fixed shaft 51 is engaged in the rotating hub 52, in order to constitute a rotating distributor 50. The fixed shaft 51 is fixed and held on the frame 10 by means of a bracket 11 which ensures a robust and precise positioning for the fixed shaft 51, as well as a transfer of forces.

[0036] The blow nozzles 30 (also called cannulas) are mounted to move relative to the frame 10 so that they can be engaged and disengaged from the casings 100 during the rotation of the turntable 20. For this purpose, a cam system can be provided, comprising in particular a cam track 32 fixed to the frame 10 and receiving cam followers 33 (rollers or bearings) coupled to the blow nozzles 30. The blow nozzles 30 can be mounted in a sliding connection (not shown) on the frame 10, so that the rotation of the turntable 20, which carries the blow nozzles 30 coupled to the cam followers 33, imposes a vertical reciprocating movement on the blow nozzles 30 via the cam track 32. It can be noted that the blow nozzle 30 on the right side of [Fig. 1] is in the raised position. and freed from the envelope 100 located opposite, and that the blow nozzle 30 on the left side of the [Fig.l] is in the lowered position and engaged in the envelope 100 located opposite. .

[0037] The blow nozzles 30 are supplied with compressed air from a single compressed air source, from the fixed supply fitting 40 and via the rotary distributor 50. Then, flexible hoses 31 directly connect the rotating hub 52 of the rotary distributor 50 to the blow nozzles 30.

[0038] Indeed, in order to effectively clean the casings 100, pressurized air is injected into each casing 100 to expel impurities and any dust. A suction device (a hood) can be provided at the necks or above the cleaning machine to collect these impurities and any dust projected out of the casings 100.

[0039] As shown in [Fig. 2], the rotating hub 52 receives the fixed shaft 51, bearings 53, and seals 56, 57. The bearings 53 provide an effective pivot connection, and the seals (O-rings 56 mounted in a groove under flat seals 57) ensure good sealing, while a spring ring 54 locks the fixed shaft 51 onto the rotating hub 52. Two sets of seals 56, 57 are provided axially on either side of the radial shaft channel 512, with an O-ring 56 mounted at the bottom of the groove and a flat seal 57 in contact with the fixed shaft 51, and pushed against it by the O-ring 56. A material compatible with food standards can therefore be used for the flat seal 57 (a polymer such as polyethylene tetrafluoride, for example), with a large contact area and sufficient contact force provided by the seal. toroid 56. The rotating hub 52 can be made of aluminum, and the fixed shaft 51 in stainless steel.

[0040] In detail, the fixed shaft 51 is axially drilled / tapped to receive the fixed supply fitting 40 via an axial shaft channel 511, and a radial shaft channel 511 allows the compressed air to be distributed radially to the rotating hub 52 in a distribution area surrounded by the two groups of seals 56, 57.

[0041] The rotating hub 52 comprises a plurality of radial hub channels 521 and a plurality of axial hub channels 522, each communicating with one of the radial hub channels 521. For manufacturing reasons, the radial hub channels 521 are through channels and a plug 55 is provided to plug each radial hub channel 521.

[0042] Radially arranged passages 523 in the rotating hub 52 provide an internal space between the seals 56, 57 and the bearings 53, allowing communication with the outside. This design prevents the bearings 53 and their flanges from being subjected to pressure.

[0043] Figure 3 shows the rotary distributor 50 in top view. It can be noted that the rotating hub 52 is provided with 24 axial hub channels 522, but more or fewer of these axial hub channels 522 can be provided.

[0044] To save compressed air, it is proposed to supply the blow nozzles 30 only on part of the conveying cycle, and in particular only when this compressed air can effectively clean the envelopes 100.

[0045] To this end, the fixed shaft 51 includes, at the downstream end of the radial shaft channel 512, a fixed outlet forming a distribution window 513 which extends over a limited angular blowing sector Saf, as shown in [Fig. 3]. Indeed, as can be seen in [Fig. 2], the distribution window 513 is not formed around the entire periphery of the fixed shaft 51 and can only supply the radial hub channels 521 that are opposite it. Referring back to [Fig. 3], it can be noted that only eight radial hub channels 521 are opposite the distribution window 513 and are effectively supplied. The clockwise rotation of the rotating hub 52 will successively supply the radial hub channels 521 that pass opposite the distribution window 513.

[0046] In [Fig. 3], it can be seen that the angular blowing sector Saf extends over approximately 150°, but a different range, either larger or smaller, can be envisaged. In any case, the compressed air supply to the blowing nozzles is significantly limited compared to a known machine that supplies the blowing nozzles 30° over 360°, and a compressed air saving of at least 50% can be estimated compared to a conventional machine. As an example, after installing such a rotary distributor on a cleaning machine, defining an angular blowing sector Saf of approximately 150°, the supply pressure could be reduced from an initial value from 7 bars to a value between 1 and 2 bars.

[0047] Such a single distribution window 513 is easy to manufacture, and means for fastening (for example, threads in the fixed shaft) can also be provided for attaching shims that will allow adjustment of the value of the angular blowing sector Saf. The fixed shaft 51 can also be exchanged for another fixed shaft 51 machined differently to make such an adjustment. Finally, in the area of ​​the rotating distributor 50 between the two groups of seals 56, 57, a radial clearance of between 0.025 mm and 0.1 mm, for example 0.05 mm, can be provided, which ensures that little air can escape into the other radial hub channels 521 that are not opposite the distribution window 513, even if no seal is provided.

[0048] It can be foreseen that the bracket 11 includes means for adjusting its position (oblong holes, adjustable parts) to adjust vertically and especially angularly the position of the fixed shaft 51, in order to ensure that the distribution window 513 is positioned so that the supplied blow nozzles 30 are those which are engaged in the envelopes 100, such as the one located to the left of the [Fig.1].

[0049] Thus, the blow nozzles 30 are only supplied when they are engaged in the envelopes 100, by adjusting the angular position of the fixed shaft 51, instead of, for example, moving the cam track 32.

[0050] It can be noted that the flexible hoses 31 directly connect the blow nozzles 30, thus avoiding the need for sliding pistons and / or friction seals to provide a seal between the rotating hub 52 and the blow nozzles 30. It can also be noted that the flexible hoses 31 deform throughout the rotation cycle of the turntable 20, and the spacer foot 58 has a height calculated to guarantee a minimum length for the flexible hoses 31. The length (for example, approximately 250 mm - 300 mm) of the spacer foot 58 can be designed to position the upper face of the rotating hub 52 at mid-height between the top dead center and the bottom dead center of the pneumatic connector of the flexible hoses 31 on the blow nozzles 30. In this way, pressure losses are limited, as are friction, pinching, and tangling between the flexible hoses 31.

[0051] It will be understood that various modifications and / or improvements obvious to a person skilled in the art can be made to the different embodiments of the invention described in this description without departing from the scope of the invention.

Claims

Demands

1. Blow-cleaning machine for casings (100) forming containers or container manufacturing intermediates, comprising: - a frame (10), - a rotating platform (20), pivotally mounted on the frame (10) and arranged to receive and convey a plurality of casings (100) to be cleaned between an inlet position and an outlet position, - at least one blow-cleaning nozzle (30), mounted on the rotating platform (20) and arranged to blow-clean at least one casing received and conveyed by the rotating platform (20) between the inlet position and the outlet position, - a fixed supply connection (40), fixedly mounted on the frame (10) and arranged to be connected to a blow-air source, characterized in that the cleaning machine comprises at least one rotary distributor (50) arranged between the fixed connection and said at least one blow-cleaning nozzle (30),comprising a fixed shaft (51) with a single distribution window (513) arranged to supply said at least one blow nozzle (30) with blow air only over a predetermined angular blow sector (Saf) between the inlet position and the outlet position.

2. Cleaning machine according to claim 1, wherein the angular blowing sector (Saf) is: - less than a defined angular sector between the inlet position and the outlet position of the rotating plate (20), and / or - within a range from 120° to 210° and preferably within a range from 140° to 180°.

3. Cleaning machine according to any one of claims 1 to 2, wherein the rotating pneumatic distributor comprises: - a rotating hub (52) mounted on the rotating plate (20), - the fixed shaft (51) integral with the frame (10), and wherein the fixed shaft (51) comprises a fixed supply passage with a downstream outlet to the rotating hub (52), the downstream outlet forming the distribution window (513) and extending over the angular blowing sector (Saf).

4. Cleaning machine according to claim 3, wherein the rotating hub (52) comprises at least one rotating feed passage including a rotating outlet connected with said at least one blow nozzle (30).

5. Cleaning machine according to claim 3 or 4, wherein the rotating pneumatic distributor includes sealing means arranged axially on either side of the downstream outlet.

6. Cleaning machine according to claim 5, wherein the sealing means comprise at least one seal, such as an O-ring (56), and preferably a composite seal comprising an O-ring (56) housed in a groove formed in one of the fixed shaft (51) or the rotating hub (52) associated with a polymer flat seal (57) housed in the groove between the O-ring and the other of the fixed shaft (51) or the rotating hub (52).

7. Cleaning machine according to any one of claims 5 to 6, wherein the rotating distributor (50) comprises at least one guide bearing (53), and a decompression orifice (523) provided in the rotating hub (52), and arranged between the sealing means and the guide bearing (53).

8. Cleaning machine according to any one of claims 4 to 7, comprising at least one flexible tube (31) directly connecting said at least one rotating outlet with said at least one blow nozzle (30).

9. Cleaning machine according to any one of claims 1 to 8, wherein said at least one blow nozzle (30) is mounted movable relative to the rotating plate (20) so as to be able to engage in the envelope, at least partially on the angular blowing sector (Saf).

10. Cleaning machine according to claim 9, comprising a cam track (32) engaged with at least one cam follower (33) arranged to cause relative movement of the blow nozzle (30) with respect to the turntable (20).

11. Cleaning machine according to any one of claims 9 to 10, wherein said at least one blow nozzle (30) is mounted in a sliding connection relative to the rotating plate (20).

12. Cleaning machine according to any one of claims 9 to 11, wherein the angular blowing sector (Saf) is defined so that the blowing nozzle (30) is fed when the blowing nozzle (30) is engaged in the casing.

13. A cleaning machine according to any one of claims 1 to 12, comprising suction means arranged for collecting residues blown by the blower nozzle (30).

14. Cleaning machine according to any one of claims 1 to 13, wherein the envelopes (100) are preforms of plastic containers.

15. Cleaning machine according to any one of claims 1 to 14, wherein the rotary distributor (50) includes at least one spacer foot (58).

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