Imaging device for inspecting containers

Abstract

The imaging device (1) includes an image acquisition device (4) facing a semi-reflective mirror (20) and a light source (6) facing the semi-reflective mirror (20), which extends within a volume (18) of a housing (8) including an acquisition opening (22). The housing (8) includes a mounting opening (24) for the image acquisition device (4) and a receiving opening (34) for the light source (6), and the volume (18) of the housing (8) is sealed by a window (40) extending within the acquisition opening (22), the image acquisition device (4), and the light source (6).

Description

Technical Field

[0001] The present invention relates to an imaging apparatus for an inspection device of a container, the imaging apparatus of this type comprising an image acquisition device facing a semi-reflective mirror and a light source facing the semi-reflective mirror, the semi-reflective mirror being configured to axially align the image acquisition direction of the image acquisition device with the direction of light emitted by the light source, the semi-reflective mirror extending within the internal volume of a housing including an axially extending acquisition opening.

[0002] The present invention also relates to an apparatus for inspecting at least one container, including such an imaging device.

[0003] This invention is applicable to any type of container, and particularly to preforms or finished containers made from such preforms. Background Technology

[0004] Preforms can be used to make finished containers by blowing preheated preforms. Such a preform includes a body that deforms during the blowing process and a neck that has been molded to its final shape and remains unchanged during the blowing process.

[0005] To produce high-quality finished containers, it is important to ensure that the preforms used have satisfactory parameters before their deformation. Therefore, it is well known to inspect the preforms before they are placed in the molds of the blow molding wheels, in which they are blow molded into containers.

[0006] This inspection is performed, for example, based on images of each preform acquired and analyzed by an image processing device.

[0007] More specifically, the imaging device is intended, for example, to be used to obtain one or more images of the preform's collar and / or edges, for example, to check for the presence of collar and / or buvant defects and / or to check the angular orientation of the preform.

[0008] To obtain satisfactory images to ensure these inspections, the collar and / or mouth should be illuminated by light emitted in a direction aligned with the shooting direction of the image acquisition device, such as corresponding to the axis of the preform being inspected. For this purpose, it is anticipated, for example, that the image acquisition device and the light source are arranged on one side of a semi-reflective mirror configured to align the emitted light with the shooting direction.

[0009] However, such a setup is easily contaminated, fogged, and / or exposed to liquids, especially when used in container manufacturing facilities, which reduces the quality of the acquired images and prevents effective inspection of the preform neck ring. Summary of the Invention

[0010] One of the objectives of this invention is to overcome these drawbacks by proposing an imaging device that can illuminate a container in the same direction as the shooting direction and be protected from the influence of the external environment.

[0011] For this purpose, the present invention relates to an imaging device of the aforementioned type, wherein the housing includes a mounting opening for an image acquisition device that is sealed from the outside of the internal volume on the mounting opening, and a receiving opening for a light source that is sealed from the outside of the internal volume by the receiving opening, and the internal volume of the housing is sealed by a window extending in the acquisition opening, the image acquisition device, and the light source.

[0012] By designing a sealed enclosure that houses the image acquisition unit, light source, and windows, the various components of the imaging unit, particularly the semi-reflective mirror, are protected from the external environment, ensuring satisfactory image quality. Furthermore, by mounting the image acquisition unit and arranging the light source in appropriate openings within the enclosure, these components remain accessible from the outside, allowing for simple and quick maintenance. Finally, the imaging unit constitutes a compact and maneuverable monolithic module, making it easy to implement in container manufacturing facilities.

[0013] The imaging apparatus according to the present invention may include one or more of the following features, which may be employed individually or in any combination conceivable in the art:

[0014] A semi-reflective mirror is configured to transmit an image through the axial image acquisition device and reflect light emitted from the light source axially.

[0015] - A semi-reflective mirror is configured to transmit light emitted from a light source along the axis and reflect the image to the image acquisition device.

[0016] - The image acquisition device includes a lens extending within the internal volume of a housing, and the lens is mounted on an acquisition unit extending outside the internal volume.

[0017] The housing includes a maintenance opening extending toward the semi-reflective mirror, which is sealed and reversibly closed by a cover.

[0018] - The housing includes an inner wall defining the internal volume, said inner wall being made of or coated with a non-reflective material.

[0019] - The inner wall includes curved and / or textured sections at least around the acquisition opening, installation opening, and receiving opening.

[0020] - The opening extends between a first end leading to the internal volume and a second end leading to the outside of the internal volume; the window extends at the first end of the opening.

[0021] - The first connector ensures that the mounting opening is sealed by the image acquisition device and the second connector ensures that the receiving opening is sealed by the light source.

[0022] According to another aspect, the present invention relates to an inspection apparatus for at least one container, the container extending along an axis, the inspection apparatus comprising a container receiving support and an imaging device as described above, the axis of the imaging device coinciding with the axis of the container when the container is received by the receiving support. Attached Figure Description

[0023] Other aspects and advantages of the invention will become clearer upon reading the following description, which is given by way of non-limiting example only and with reference to the accompanying drawings, wherein

[0024] [ Figure 1 ] - [ Figure 1 [This is a partial perspective view of an apparatus for inspecting a container, including an imaging device according to the present invention.]

[0025] [ Figure 2 ] - [ Figure 2 ]yes[ Figure 1 A perspective schematic diagram of the imaging device, and

[0026] [ Figure 3 ] - [ Figure 3 ]yes[ Figure 2 A cross-sectional schematic diagram of the imaging device shows the interior of the outer casing. Detailed Implementation

[0027] Reference Figure 1 and Figure 2 The description includes an imaging device 1 for a container, particularly a preform 2, comprising an image acquisition device 4 and a light source 6 mounted on a housing 8.

[0028] The preform 2 is intended to form a container after a heating, blowing, or stretch-blowing step. Such a preform 2 essentially comprises a body 10 and a neck 12. The body 10 extends along axis A and has, for example, a test tube shape extending between the bottom and the neck 12, which forms the open end of the test tube.

[0029] The neck 12 extends, for example, between a neck ring 14 and a mouth 15. The neck ring 14 extends in a radial plane projecting outward from the body 10 and clearly perpendicular to axis A. The mouth 15 forms the upper surface and upper end of the preform 2. The neck ring 14 forms, for example, a transfer surface for the preform 2 and the finished container made from the preform 2. The mouth 15 defines and surrounds the open end of the preform 2.

[0030] The portion of the preform 2 extending from the neck ring 14 to the mouth 15 includes, for example, threads 16 that can secure a stopper to a container made from the preform 2.

[0031] The preform 2 is made of a thermoplastic material, such as polyethylene terephthalate (PET). When the body 10 of the preform 2 is heated above the glass transition temperature of the thermoplastic material during the heating step of the preform 2, the body 10 of the preform 2 becomes ductile so that when compressed air is injected into the preform 2 through the open end during the blowing or stretch-blow step of the preform 2, the body 10 can subsequently deform into the body of a container. In a known manner, the neck 12 of the preform 2 is not heated during the heating step and remains undeformed during the blowing or stretch-blow step so that the neck 12 of the preform 2 has the neck shape of the container made from the preform 2.

[0032] To produce high-quality containers, it should be ensured that the preform 2 itself is of high quality and adheres to certain parameters, particularly at the neck 12 of the preform, and even more so at the neck ring 14 and / or the mouth 15. Scratches and / or defects on the DE joint plane in the neck ring 14 and / or the mouth 15 should be avoided. Furthermore, for certain preforms 2, markings should be positioned on the neck ring 14 to check the angular orientation of the preform 2. It is well known that angular orientation is important for the subsequent processing of the preform 2 and / or the container obtained from it. Finally, the neck ring 14 and / or the mouth should be indicated with specified dimensions within a certain tolerance range. This list of parameters is given only as an example, and other parameters can be taken into consideration to ensure that the finished containers produced from the preforms will be of high quality.

[0033] To verify that the collar 14 and / or mouth 15 comply with these parameters, it is anticipated that an inspection device including an imaging device 1 will be used to inspect the collar 14 and / or mouth 15, for example, before and / or after the preform 2 is heated. The imaging device is configured to acquire at least one image of the collar 14 and / or mouth 15 of the preform 2 to be inspected.

[0034] More specifically, the imaging device 1 is configured to acquire at least one image of the neck collar 14 and / or mouth 15 in a radial plane extending from the neck collar 14 and / or mouth 15. In other words, the imaging device 1 is positioned above or below the preform 2 and configured to acquire an image in a field of view corresponding to the radial plane extending from the neck collar 14 and / or mouth 15 and perpendicular to axis A, according to a shooting direction substantially parallel to axis A of the preform 2. According to an embodiment, the shooting direction is aligned with, i.e., coincident with, axis A of the preform 2, as shown in the example. Figure 3As particularly evident in the image. In order to obtain high-quality images that can be used for inspection purposes, the imaging device 1 is further configured to illuminate the neck collar 14 and / or the mouth 15 according to the shooting direction. In other words, the light emission direction illuminating the neck collar 14 and / or the mouth 15 coincides with the shooting direction.

[0035] For this purpose, such as [ Figure 3 As shown, the housing 8 defines the internal volume 18 of the receiving semi-reflective mirror 20, towards which both the image acquisition device 4 and the light source 6 are oriented. The semi-reflective mirror 20 is configured to align the shooting direction of the image acquisition device 4 and the direction of the light emitted by the light source 6 with the axial direction of the acquisition opening 22 through the housing 8 and to be significantly parallel to, or even coincide with, the axis A of the preform 2. More specifically, the semi-reflective mirror 20 is, for example, a 50 / 50 mirror, meaning it transmits 50% of the light and reflects 50% of the light.

[0036] For this purpose, the image acquisition device 4 is mounted on the mounting opening 24 of the housing 8, which is configured to face the semi-reflective mirror 20. According to […] Figure 3 In the embodiment shown, the image acquisition device 4 is more specifically arranged to face the transmission surface 26 of the semi-reflective mirror 20 so that the acquired image is transmitted axially to the image acquisition device 4. Therefore, according to this embodiment, the shooting direction of the image acquisition device 4 directly coincides with the axial direction, and the acquired image is transmitted directly to the image acquisition device 4 through the semi-reflective mirror 20 without being deflected by it. In this case, the mounting opening 24 is parallel to the acquisition opening 22; these openings are coaxial and extend axially. The mounting opening 24 extends between the internal volume 18 of the housing 8 and the exterior of the housing 8, and the image acquisition device 4 is mounted on this mounting opening 24 from the exterior of the housing 8. In other words, during the installation of the image acquisition device 4, it is approached from the exterior of the housing 8 and secured to the mounting opening 24 by entering the internal volume 18 of the housing 8 through the external mounting opening 24. Therefore, the image acquisition device 4 remains accessible from the exterior of the housing 8 and can be easily removed from the housing, for example, to replace it with another image acquisition device 4 or for maintenance operations.

[0037] According to one embodiment shown in the figure, the image acquisition device 4 includes a lens 28 mounted on the acquisition unit 30 to form a camera capable of acquiring images. When the image acquisition device 4 is mounted on the mounting opening 24, the lens 28 extends, for example, within the internal volume 18 and the acquisition unit 30 extends to the outside of the housing 8, such as […]. Figure 3 As shown in the figure. Therefore, during the installation of the image acquisition device 4, the lens 28 passes through the mounting opening 24 and the acquisition unit 30 is mounted close to the mounting opening 24 to close the latter.

[0038] The image acquisition device 4 is mounted in a sealed manner on the mounting opening 24. In other words, when the image acquisition device 4 is mounted on the mounting opening 24, any external elements, especially dust or liquids, are prevented from passing through the mounting opening 24 and entering the internal volume 18 of the housing 8. According to an embodiment, this sealing is ensured by a first connector 32 that ensures a sealed closure of the image acquisition device 4 to the mounting opening 24.

[0039] The light source 6 is received in the receiving opening 34 of the housing 8, which is arranged so that the light source 6 faces the semi-reflective mirror 20. According to [ Figure 3 In the embodiment shown, the image acquisition device 4 is arranged facing the transmissive surface 26 of the semi-reflective mirror 20, and the light source 6 is arranged facing the reflective surface 36 of the semi-reflective mirror 20, so that the light emitted by the light source is reflected on the semi-reflective mirror 20 and, after reflection, is guided axially to the acquisition opening 22. Therefore, according to this embodiment, when the semi-reflective mirror 20 is oriented at a 45° angle relative to the axial direction, the light emission direction of the light source 6 is approximately perpendicular to the axial direction, and the light emitted by the light source 6 is reflected by the reflective surface 36 of the semi-reflective mirror to coincide with the imaging direction and the reflected axial direction. In this case, the receiving opening 34 is perpendicular to the acquisition opening 22 and the mounting opening 24. The receiving opening 34 extends between the internal volume 18 of the housing 8 and the outside of the housing 8, and the light source 6 is mounted on this receiving opening 34 from the outside of the housing 8. In other words, during the mounting of the light source 6, it approaches from the outside of the housing 8 and is fixed to the receiving opening 34 by entering the internal volume 18 of the housing 8 from the outside through the receiving opening 34. Therefore, the light source 6 remains accessible from the outside of the housing 8 and can be easily removed from the housing, for example, to replace it with another light source or for maintenance operations.

[0040] The light source 6 is configured, for example, to emit radiation in the visible light range, and particularly between 400 and 700 nanometers.

[0041] The light source 6 is mounted in a sealed manner on the mounting opening 24. In other words, when the light source 6 is received in the receiving opening 34, any external elements, especially dust or liquids, are prevented from passing through the receiving opening 34 and entering the internal volume 18 of the housing 8. According to an embodiment, this sealing is ensured by a second connector 32 that ensures a sealed closure of the light source 6 to the receiving opening 34.

[0042] Of course, the mounting opening 24 and the receiving opening 34 can be arranged relative to the semi-reflective mirror 20 so that the semi-reflective mirror transmits the light emitted by the light source 6 axially and reflects the image to the image acquisition device 4. Therefore, in this case, the mounting opening 24 is arranged so that the image acquisition device 4 is oriented towards the reflecting surface 36 of the semi-reflective mirror 20, and the receiving opening 34 is arranged so that the light source 6 is oriented towards the transmitting surface 26 of the semi-reflective mirror 20. Also in this case, the mounting opening 24 is perpendicular to the acquisition opening 22, and the receiving opening 34 is parallel to and coaxial with the acquisition opening 22.

[0043] The access opening 22 is sealed in a sealed manner by a transparent window 40 extending within the access opening 22. Therefore, the window 40 prevents any element, particularly dust or liquid, from entering the internal volume 18 through the access opening 22. According to an embodiment, the access opening extends axially between a first end 42 leading to the internal volume 18 and a second end 44 leading to the outside of the internal volume 18, and the window 40 is mounted in the access opening 22 so as to extend at the first end 42. Such an embodiment allows the window 40 to be positioned rearward inside the access opening 22 so that it is not directly exposed to the external environment of the housing 8, which limits the risk of damage to the window 40, for example, by scratching. The window 40 is made of, for example, glass or plastic material. The window 40 is, for example, anti-reflective and transmits 100% of light without altering its path. Therefore, light emanating from the housing 8 and entering the housing through the access opening is entirely axially oriented. A joint is, for example, intended around the window 40, between the window and the housing 8, to ensure a seal at the access opening 22 receiving the window 40.

[0044] As previously described, when the image acquisition device 4 is mounted on the mounting opening 24 and the light source 6 is mounted on the receiving opening 34, all openings of the housing 8 are sealed so that the internal volume 18 cannot be reached from the outside of the housing 8. This protects the semi-reflective mirror 20, the lens 28 of the image acquisition device 4, and the light source 6 from the external environment of the housing 8 and maintains the quality of the images acquired by the image acquisition device 4. The sealing performance of the housing 8 conforms, for example, to the sealing performance standard IP66 (protection index 66) defined by standard NF EN60 529.

[0045] The housing 8 is advantageously constructed to limit, or even eliminate, light reflection within the internal volume 18, except for reflections on the reflective surface 36 of the semi-reflective mirror 20. For this purpose, the housing 8 is made of, for example, a non-reflective material and / or the inner walls of the housing 8 defining the internal volume 18 are coated with a non-reflective material, such as felt and / or a black coating. Furthermore, to still avoid reflection, the shape of the inner walls is, for example, configured to limit protruding angles within the internal volume 18. For this purpose, as shown in the figures, the inner walls include curved and / or textured sections at least around the mounting opening 24, receiving opening 34, and obtaining opening 22. Curved sections, for example, refer to sections of the inner walls having circular, oval, or elliptical cross-sections around the mounting opening 24, receiving opening 34, and obtaining opening 22. When the stoppers need to extend within the internal volume 18 of the housing 8, they are, for example, rounded to avoid forming reflective areas within the internal volume 18, such as... Figure 3 As particularly evident in the diagram. Textured sections refer to sections whose inner walls include, for example, serrated shapes, which are configured to increase light reflection between these shapes and thus form a light trap that prevents trapped light from being reflected within the inner volume 18.

[0046] According to an embodiment, the housing 8 further includes at least one maintenance opening facing the semi-reflector 20 and closed in a sealed and reversible manner by a cover 46 during normal operation of the imaging device 1. For example, to allow free access to the semi-reflector 20 for replacement or maintenance purposes, the maintenance opening allows access to the internal volume 18 when the cover 46 is removed from the maintenance opening. The cover 46 is, for example, made of the same material as the housing 8 and is also rounded to limit light reflection. A connector is designed, for example, between the cover 46 and the maintenance opening to maintain the seal of the housing 8 at the maintenance opening.

[0047] The imaging device is particularly compact, which makes its installation in the container 2 production facility easy.

[0048] According to the embodiment shown in [Figure 11], the imaging device 1 is mounted, for example, on a support 48 so as to extend toward the preform 2 support. Such a support can move relative to the imaging device, which is then adjusted to acquire continuous images of the preform moving toward the imaging device 1. The imaging device 1 is connected to the support 48, for example, so that the imaging device 1 can be repositioned relative to the facing preform 2, particularly if the preform 2 is tilted on its support, with the axis A of the preform 2 aligned with the axial direction of the imaging device 1.

[0049] It should be noted that the above description has been made with reference to the inspection of the neck ring 14 and / or mouth 15 of the preform 2, because in this case, it is important that the light emitted by the light source 6 is aligned with the shooting direction of the image acquisition device 4. However, of course, the present invention can be applied to the inspection of the body 10 and / or its neck 12 of the preform 2, and even to the inspection of the finished container obtained from the preform 2.

[0050] Therefore, the present invention also generally relates to an inspection device for a container extending along axis A, the inspection device comprising a container receiving support and an imaging device 1 as described above, the axis of the imaging device 1 coinciding with axis A of the container when the container is received by the receiving support.

Claims

1. An imaging apparatus (1) for inspecting a container, comprising an image acquisition device (4) facing a semi-reflective mirror (20) and a light source (6) facing the semi-reflective mirror (20), the semi-reflective mirror (20) being configured to axially align the image acquisition direction of the image acquisition device (4) with the direction of light emitted by the light source (6), the semi-reflective mirror (20) extending within an internal volume (18) of a housing (8), the housing (8) including an axially extending acquisition opening (22), characterized in that... The housing (8) includes a mounting opening (24) for an image acquisition device (4) which is mounted in a sealed manner from the outside of the internal volume (18) on the mounting opening (24), and a receiving opening (34) for a light source (6) which is received in a sealed manner from the outside of the internal volume (18) by the receiving opening (34). The internal volume (18) of the housing (8) is sealed by a window (40) extending in the acquisition opening (22), the image acquisition device (4) and the light source (6).

2. The imaging apparatus according to claim 1, wherein the semi-reflective mirror (20) is configured to transmit an image along the axial direction to the image acquisition device (4) and to reflect light emitted by the light source (6) along the axial direction.

3. The imaging apparatus according to claim 1, wherein the semi-reflective mirror (20) is configured to transmit light emitted by the light source (6) along the axis and to reflect an image to the image acquisition device (4).

4. The imaging apparatus according to any one of claims 1 to 3, wherein the image acquisition device (4) includes a lens (28) extending within the internal volume (18) of the housing (8) and said lens (28) is mounted on an acquisition unit (30) extending outside the internal volume (18).

5. The imaging apparatus according to any one of claims 1 to 4, wherein the housing (8) includes a maintenance opening extending toward the semi-reflective mirror (20), the maintenance opening being sealed and reversibly closed by a cover (46).

6. The imaging apparatus according to any one of claims 1 to 5, wherein the housing (8) includes an inner wall defining an internal volume (18), said inner wall being made of or coated with a non-reflective material.

7. The imaging apparatus of claim 6, wherein the inner wall comprises curved and / or textured sections at least around the acquisition opening (22), the mounting opening (24) and the receiving opening (34).

8. The imaging apparatus according to any one of claims 1 to 7, wherein the acquisition opening (22) extends between a first end (42) leading to the internal volume (18) and a second end (44) leading to the outside of the internal volume (18), and the window (40) extends at the first end (42) of the acquisition opening (22).

9. The imaging apparatus according to any one of claims 1 to 8, wherein the first connector (32) ensures that the mounting opening (24) is sealed closed by the image acquisition device (4) and the second connector (38) ensures that the receiving opening (34) is sealed closed by the light source (6).

10. An inspection apparatus for inspecting at least one container, the container extending along an axis (A), the inspection apparatus comprising a receiving support for the container and an imaging device (1) according to any one of claims 1 to 9, the axis of the imaging device (1) coinciding with the axis (A) of the container when the container is received by the receiving support.

Images