Integrated leak and vision inspection system

• US 6,473,169 B1
• Filed: 05/03/2000
• Issued: 10/29/2002
• Est. Priority Date: 05/03/2000
• Status: Expired due to Fees

• Current Assignee: Air Logic Power Systems, Inc.
• Original Assignee: Air Logic Power Systems, Inc.
• Inventors: Meckl, Michael F., Jakubowski, Andrew T., Dawley, James M.
• Primary Examiner(s): STAFIRA, MICHAEL PATRICK
• Application Number:
  US09/563,960
• Time in Patent Office: 909 Days
• Field of Search: 356/239--24, 250/223.B, 250/223.R, 250/556, 250/227.2
• US Class Current: 356/239.4
• CPC Class Codes: B29C 2049/7876 Defects
• CPC Class Codes: G01M 3/3263 using a differential pressure detector G01M3/3245, G01M3/3272 take precedence
• CPC Class Codes: G01M 3/38 by using light G01M3/02 takes precedence
• CPC Class Codes: G01N 2033/0081 containers; packages; bottles
• CPC Class Codes: G01N 21/9081 Inspection especially designed for plastic containers, e.g. preforms

Abstract

An integrated leak and vision inspection system is provided that accurately and efficiently inspects a bottle or other container for manufacturing defects. The system provides a series of visual inspection stations with cameras and lighting that are integrated onto a rotary inspection system for on-line inspection of containers. A microprocessor in data communication with each of the inspection stations receives and analyzes image data of the particular area or parameter of the container being inspected or tested, and generates data relating to the container based upon predetermined criteria. The stations are arranged to provide an integrated and fully automated and efficient inspection system. In the preferred embodiment, the system is structured with a first station integrated with an entry starwheel to inspect the top seal surface of the container. As the container moves out of the starwheel, a probe from a leak test assembly seals the container opening and the container is tested for leaks as it moves on a main turntable into and through a second station to visually inspect the neck finish. The container is then transported on the turntable to a third station integrated with an exit starwheel to visually inspect the base of the container. The exit starwheel shifts the container onto the line conveyor to a reject station, which removes any containers that are below the set standards.

Claims

1. An integrated inspection system for visually inspecting a container for defects, the container having a mouth with a top seal surface, neck, shoulder, side surface, and base;

the system comprising;

a series of visual inspection stations, each comprising a surface to support the container thereon, and an assembly to inspect a select portion of the container;

an infeed mechanism to move the container into the system;

an exit mechanism to move the container out of the system;

a conveyor to move the container through the system; and

a microprocessor to receive and analyze data signals received from the visual inspection stations and generate data relating to the container;

wherein the series of visual inspection stations, includes;

a) a first visual inspection station to inspect the top seal surface of the container, the top seal surface inspection assembly including;

a light source mounted in a vertical orientation to illuminate the top seal surface of the container when positioned on the support surface;

a camera mounted in a vertical orientation to image the top seal surface of the container when positioned on the support surface; and

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the top seal surface of the container and transmit the data signal to the microprocessor;

b) a second visual inspection station to inspect the neck finish of the container, the neck finish inspection assembly including;

a light source mounted horizontally to direct illumination over the support surface;

a reflective surface positioned to receive and reflect the illumination toward the neck of the container when positioned on the support surface;

a camera mounted horizontally to image the neck of the container when positioned on the support surface;

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the neck of the container and transmit the data signal to the microprocessor; and

c) a third vial inspection station to inspect the base of the container, the support surface structured to allow light to pass therethrough, and the base inspection assembly including;

a light source mounted beneath the support surface to illuminate the base of the container when positioned on the support surface;

a camera mounted in a vertical orientation to image the base of the container through the neck when the container is positioned on the support surface; and

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the base of the container and transmit the data signal to the microprocessor; and

wherein the conveyor comprises the infeed mechanism to convey the container into the first visual inspection station and the exit mechanism to convey the container out of the third visual inspection station.

2. The inspection system according to claim 1, further comprising:

a photosensitive detector (photoeye) positioned at a location in advance of each visual inspection station, to sense the presence of the container and send a signal to the microprocessor to initiate an inspection operation sequence.

3. The inspection system according to claim 1, further comprising a video screen, a printer, or a combination thereof, connected to the microprocessor to display the generated data.

4. The inspection system according to claim 1, further comprising a mechanism to eject a defective container from the system, positioned along a line conveyor situated downstream from the exit mechanism, and connected to the microprocessor;

wherein the microprocessor is programmed to analyze the data signals received from the data signaling devices of the inspection stations and send a signal to the container eject mechanism to move the container off of the line conveyor based upon a predetermined criteria.

5. The inspection system according to claim 1, wherein the conveyor is a continuously moving conveyor belt, a rotating turntable, or a combination thereof.

6. The inspection system according to claim 1, wherein the infeed and exit mechanisms are starwheels, and the container support surfaces are deadplates.

7. The inspection system according to claim 1, wherein the camera and the light source of the top seal surface inspection assembly are co-axially mounted on a frame and vertically adjustable to modify the position of the light source and the camera in relation to the mouth of the container when positioned on the support surface.

8. The inspection system according to claim 1, wherein the light source of the neck finish inspection assembly is connected to fiber-optic light guides mounted on the camera, and the camera is mounted on a frame and vertically adjustable to modify the position of the light guides and the camera in relation to the neck of the container when on the support surface.

9. The inspection system according to claim 1, wherein the camera of the base inspection assembly is mounted on a frame and vertically adjustable to modify the position of the camera in relation to the height of the container on the support surface.

10. The inspection system according to claim 1, wherein the camera of the neck finish inspection assembly has a telecentric lens and is mounted horizontally to image the neck of the container when the container is positioned on the support surface within a set zone within the station.

12. The inspection system according to claim 1, wherein the top seal surface inspection assembly is positioned within the infeed mechanism, and the infeed mechanism is structured to convey the container onto the container support surface for the inspection operation, and off the support surface and onto the conveyor to move the container to a subsequent inspection station.

13. The inspection system according to claim 1, wherein the base inspection assembly is positioned within the exit mechanism, and the exit mechanism is structured to convey the container onto the container support surface for the inspection operation, and off the support surface and onto a line conveyor to move the container out of the inspection system.

14. The inspection system according to claim 1, wherein the support surface of the base inspection assembly comprises a semi-transparent material.

15. The inspection system according to claim 1, wherein the support surface of the base inspection assembly comprises a focusing lens, a light diffuser, an iris, an interchangeable lighting aperture plate, or a combination thereof, to control the size of the opening for the light through the support surface.

16. The inspection system according to claim 1, further comprising a leak testing assembly to test integrity of the container, the leak testing assembly comprising:

a downwardly extending plunger mounted on a carriage for vertical movement, a disc affixed to one end of the plunger to contact and seal the mouth of the container, and a port/opening to inject air into the container; and

a data signaling device connected to the microprocessor, to receive a data signal from a first position sensor to commence movement of the plunger onto the mouth of the container, receive a data signal from the plunger representative of air pressure within the container over a set time period, transmit said air pressure data signal to the microprocessor, and receive a signal from a second position sensor to commence movement of the plunger off of the mouth of the container.

17. The inspection system according to claim 16, wherein the plunger is structured to apply a predefined vertical force to the container to test topload deflection, and the plunger includes a sensor to transmit a signal when the disc of the plunger is at a predetermined height for the container, and the data signaling device receives a data signal from the plunger representative of the location of the location of the disc in relation to the predetermined height of the container, and transmits said data signal to the microprocessor.

18. The inspection system according to claim 16, wherein the leak testing assembly is mounted to test the container as it is conveyed through a visual inspection station.

19. The inspection system according to claim 1, further comprising an assembly to inspect the sidewall of the container, the sidewall inspection assembly comprising

a support surface for the container;

two or more cameras mounted horizontally and about 90°

apart, to image the sidewall of the container when on the support surface; and

a diffuse light source mounted to backlight the container when positioned on the support surface.

20. The inspection system according to claim 1, further comprising an assembly to inspect the sidewall of the container, the sidewall inspection assembly comprising

a surface to support and rotate the container;

a camera mounted horizontally to image the sidewall of the container when positioned on the support surface; and

a diffuse light source mounted to backlight the container when positioned on the support surface.

21. The inspection system according to claim 1, wherein the sidewall inspection assembly is mounted along a line conveyor downstream from the exit mechanism.

11. An integrated inspection system for visually inspecting a container for defects, the container having a mouth with a top seal surface, neck, shoulder, side surface, and base;

the system comprising;

a series of visual inspection stations, each comprising a surface to support the container thereon, and an assembly to inspect a select portion of the container;

an infeed mechanism to move the container into the system;

an exit mechanism to move the container out of the system;

a conveyor to move the container through the system; and

a microprocessor to receive and analyze data signals received from the visual inspection stations and generate data relating to the container;

wherein the series of visual inspection stations, includes;

a) a visual inspection station to inspect the top seal surface of the container, the top seal surface inspection assembly including;

a light source mounted in a vertical orientation to illuminate the top seal sure of the container when positioned on the support surface;

a camera mounted in a vertical orientation to image the top seal surface of the container when positioned on the support surface; and

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the top seal surface of the container and transmit the data signal to the microprocessor;

b) a visual inspection station to inspect the neck finish of the container, the neck finish inspection assembly including;

a light source mounted horizontally to direct illumination over the support surface;

a reflective surface positioned to receive and reflect the illumination toward the neck of the container when positioned on the support surface;

a camera mounted horizontally to image the neck of the container when positioned on the support surface;

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the neck of the container and transmit the data signal to the microprocessor; and

c) a visual inspection station to inspect the base of the container, the support surface structured to allow light to pass therethrough, and the base inspection assembly including;

a light source mounted beneath the support surface to illuminate the base of the container when positioned on the support surface;

a camera mounted in a vertical orientation to image the base of the container through the neck when the container is positioned on the support surface; and

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the base of the container and transmit the data signal to the microprocessor; and

wherein the reflecting surface is composed of alternating black and white stripes.

22. An integrated inspection system for visually inspecting a container for defects, the container having a mouth with a top seal surface, neck, shoulder, side surface, and base;

the system comprising;

an infeed starwheel to move the container from a line conveyor and into the system;

an exit wheel to move the container out of the system and onto a line conveyor;

a main conveyor to continuously move a series of containers along a pathway through a series of visual inspection stations;

a microprocessor to receive and analyze data signals received from the visual inspection stations and generate data relating to the container based upon predetermined criteria;

wherein the series of visual inspection stations, includes;

a) a first visual inspection station positioned within the infeed starwheel, and comprising an assembly to inspect the top seal surface of the container, the top seal surface inspection assembly including;

a deadplate to support the container thereon,

a light source mounted to illuminate the top seal surface of the container;

a camera mounted in a vertical orientation to image the top seal surface of the container; and

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the top seal surface of the container and transmit the data signal to the microprocessor;

b) a second visual inspection station positioned along the main conveyor downstream from the first inspection station, and comprising an assembly to inspect the neck finish of the container, the neck finish inspection assembly including;

a surface to support the container thereon;

a light source mounted to provide a horizontally directed light beam;

a reflective surface positioned to receive and reflect the light beam to illuminate the neck of the container when positioned on the support surface;

a camera directed horizontally to image the neck area of the container when positioned on the support surface; and

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the neck of the container and transmit the data signal to the microprocessor; and

c) a third visual inspection station positioned within the exit starwheel, and comprising an assembly to insect the base of the container, the base inspection assembly including;

a deadplate to support the container thereon, and structured to allow passage of light therethrough;

a light source mounted beneath the deadplate to direct light through the deadplate and onto the base of the container;

a camera mounted in a vertical orientation to image the base of the container; and

a data signaling device connected to the camera and the microprocessor, to receive a data signal from the camera representative of the camera image of the base of the container and transmit the data signal to the microprocessor; and

wherein the main conveyor comprises the infeed starwheel to convey the container into the first visual inspection station and the exit starwheel to convey the container out of the third visual inspection station and onto the line conveyor.

23. An integrated inspection system for visually inspecting a container for defects, the container having a mouth with a top seal surface, neck, shoulder, side surface, and base;

the system comprising;

a) a conveyor to move the container through the system;

b) a series of visual inspection stations, each including;

i) a surface to support the container thereon, and

ii) an assembly to inspect a select portion of the container, including;

a light source mounted to illuminate the select portion of the container,

a camera mounted to image the select portion of the container, and

a data signaling device connected to the camera to receive a data signal from the camera representative of the camera image;

c) a microprocessor connected to the data signaling device of each of the inspection stations to receive and analyze data signals from the data signaling device, and generate data relating to the container based upon predetermined criteria;

the series of visual inspection stations including;

a first station comprising a top seal surface inspection assembly including a light source mounted in a vertical orientation to illuminate the top seal of the container, and a camera mounted in a vertical orientation to image the top seal of the container;

a second station comprising a neck finish inspection assembly including a light source mounted to provide a horizontally-oriented light beam, a reflective surface positioned to receive and reflect the fight in a horizontal orientation to illuminate the neck of the container when positioned on the support surface of said assembly, and a camera mounted in a horizontal orientation to image the neck of said container; and

a third station comprising a base inspection assembly including a light source mounted beneath the support surface of said assembly to direct light through the support surface to imitate the base of the container, and a camera mounted in a vertical orientation to image the base through an opening in the neck of the container; and

wherein the conveyor comprises an infeed mechanism to convey the container into the first station, an exit mechanism to convey the container out of the third station, and a rotatable turntable to convey the container from the infeed mechanism to the exit mechanism.

24. A method of visually inspecting for defects in a container having a mouth with a top seal surface, neck, shoulder, side surface, and base comprising:

conveying the container into an infeed starwheel and onto a support surface of a first visual inspection station comprising an assembly to visually inspect the top seal surface of the container;

visually inspecting the top seal surface of the container by activating a light source and camera mounted in the assembly to illuminate and image the top seal surface of the container while the container is positioned on the support surface of said assembly, wherein a data signal is generated by the camera representative of the image and transmitted to a microprocessor;

conveying the container onto a support surface of a second visual inspection station comprising an assembly to visually inspect the neck of the container;

visually inspecting the neck of the container by activating a light source and a camera mounted in the assembly to direct a light beam toward a reflective surface positioned behind the container to indirectly illuminate and image the neck of the container while the container is positioned on the support surface, wherein a data signal is generated by the camera representative of the image and transmitted to the microprocessor;

conveying the container into an exit starwheel and onto a support surface of a third visual inspection station comprising an assembly to visually inspect the base of the container;

visually inspecting the base of the container by activating a light source and camera mounted in the assembly to illuminate and image the base of the container while the container is positioned on the support surface, wherein a data signal is generated by the camera representative of the image and transmitted to the microprocessor;

conveying the container from the support surface and out of the exit starwheel of the base inspection assembly to a ejection station comprising a device to receive a data signal from the microprocessor relating to the container based upon predetermined criteria, and an assembly to divert the container upon receipt of such data signal indicating a defect in the container; and

activating the container diverting assembly to eject a defective container from the system.

25. The method according to claim 24, further comprising:

testing the integrity of the container by activating a plunger having a disc affixed to one end and mounted on a carriage of the system, to move vertically such that the disc seals the mouth of the container, injecting air into the container, testing the air pressure in the container for a set time period, and removing the plunger disc from the mouth of the container at the end of the set time period;

wherein a data signal is generated by a sensor on the plunger representative of the air pressure with the container, and transmitted to the microprocessor.

26. The method according to claim 25, wherein the integrity test is conducted after completion of the visual inspection of the top seal surface of the container, and as the container is conveyed to the second inspection station.

27. The method according to claim 25, further comprising testing the topload deflection of the container by activating the plunger to apply a predefined vertical force to the container,

wherein a data signal is transmitted representative of the location of the disc in relation to a predetermined height of the container and transmitted to the microprocessor.