Apparatus and method for inspecting containers

The method of testing open-ended containers for defects in the form of openings in their structure, said containers having an opening surmounted by a rim and a sidewall portion extending from said rim to a bottom portion, comprising the steps of:

• positioning said openings of a continuous sequence of said containers over apertures extending through a rotating test carrier and defining a predetermined locus of movement of said apertures;
• compressibly retaining said container rim in light-tight relationship against said rotating carrier by applying a contact member against said container bottom portions;
• providing a first light detecting device at a first station positioned adjacent said rotating carrier at said locus of movement, the interior of a said container being exposed to said first light detecting device through a said aperture when moved across said first station;
• illuminating principally the sidewall portion of a said container leading with respect to the direction of said locus of movement when said container is moved across said first station;
• generating a first output signal in response to light passing through a said defect and impinging upon said first light detecting device;
• providing a second light detecting device at a second station positioned adjacent said rotating carrier at said locus of movement, the interior of a said container being exposed to said second light detecting device through a said aperture when moved across said second station;
• illuminating principally the sidewall portion of a said container lagging with respect to the direction of said locus of movement when said container is moved across said second station;
• generating a second output signal in response to light passing through a said defect and impinging upon said second light detecting device;
• and
• sorting containers having a detected said defect from those not having a detected said defect in response to said first or second output signals.

Apparatus for testing open-ended containers for defects in the form of openings in their structure, said container having an open end surmounted by a rim, a sidewall portion extending from said rim to a bottom portion, said apparatus comprising:

• means defining a supportive frame;
• a shaft rotatably supported upon said frame and having a generally horizontally disposed axis of rotation;
• drive means for drivably rotating said shaft;
• carrier disk means fixed to and rotatable with said shaft, having a predetermined number of apertures therein uniformly mutually and symmetrically spaced a predetermined distance apart about a circular locus of movement thereof and configured in conrrespondence with the configuration of said container rim for receiving said containers in abuttive relationship at a contact surface disposed about the periphery of each said aperture;
• holder means including a plurality of reciprocative retention components corresponding in number with the number of said apertures, mounted for rotation at said shaft, each positioned at a location spaced from and disposed opposite a corresponding said aperture, each said retention component including a contact member extensible into engagement with a said container bottom portion to urge the rim thereof into light-tight abutting engagement with a said contact surface, and retractable to release said container;
• first inspection station means mounted upon said frame adjacent to, stationary with respect to and in light-tight communication with said transfer disk means and including a first photosensitive device located for successive alignment with each said aperture and said container opening associated therewith for deriving a first output signal upon exposure to light passing through a said container defect;
• second inspection station means, spaced from said first inspection station means a distance corresponding to said predetermined distance between said apertures or a select multiple thereof, mounted upon said frame adjacent to, stationary with respect to and in light-tight communication with said transfer disk means and including a second photosensitive device located for successive alignment with each said aperture and a said container opening associated therewith for deriving a second output signal upon exposure to light passing through a said container defect;
• light source means for selectively illuminating the exterior of said container when passing said first and second inspection station means;
• infeed means for feeding containers intermediate said holder means retention components and associated said contact surfaces;
• discharge means normally operative to receive each said container at a predetermined position when said holder means reciprocative retention component contact member associated therewith is retracted and actuable to negate said container reception;
• and
• control means comprising:
• encoder means responsive to said shaft rotation for deriving a clock signal corresponding with the position of each said aperture as it passes a predetermined reference position;
• first AND logic means responsive to said first output signal and said clock signal for deriving a first defect signal;
• second AND logic means responsive to said second output signal and said clock signal for deriving a second defect signal;
• sequential storage means responsive to said clock signal, having a first input zone for receiving said first defect signal and a first output for deriving said first defect signal in time synchronization correspondence with said distance between said first and second inspection station means;
• OR logic means responsive to said time synchronized first detect signal and/or said second defect signal for providing an OR logic output;
• said sequential storage means further including a second input zone for receiving said OR logic output and a second output for deriving a composite defect signal in time synchronism correspondence with the distance between said second inspection station means and said discharge means predetermined position;
• and
• switching network means responsive to said composite defect signal for actuating said discharge means.