Method and apparatus for detecting holes in plastic containers
First Claim
1. A method for monitoring the production of blow molded plastic containers to detect a defect in any of the containers comprising the steps of:
- a. loading a preform into a mold cavity at a loading station;
b. introducing pressure fluid to an interior of the preform in the mold cavity to form a blow molded plastic container while moving the mold cavity along a generally circular path;
c. acoustically sensing a defect sound resulting from the pressure fluid escaping from the interior of the container being formed at a position adjacent the path and within a portion of the path from one point at onset of preblow air to another point just after onset of high blow air; and
d. generating a control signal in response to the sensed defect sound.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and an apparatus for monitoring the production of blow molded plastic containers (20) includes a columnator (26) and sound detector (24) responsive to a defect sound of pressure fluid escaping from a container being formed in a mold cavity (14). The columnator is effective to filter the defect sound from ambient noise. An output signal generated by the sound detector is processed to generate a control signal used to reject a defective container. Preferably, the open end of the columnator is positioned between 20° and 150° from the preform loading station in a rotary platform (12) blow molding machine.
15 Citations
20 Claims
-
1. A method for monitoring the production of blow molded plastic containers to detect a defect in any of the containers comprising the steps of:
-
a. loading a preform into a mold cavity at a loading station; b. introducing pressure fluid to an interior of the preform in the mold cavity to form a blow molded plastic container while moving the mold cavity along a generally circular path; c. acoustically sensing a defect sound resulting from the pressure fluid escaping from the interior of the container being formed at a position adjacent the path and within a portion of the path from one point at onset of preblow air to another point just after onset of high blow air; and d. generating a control signal in response to the sensed defect sound. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method for monitoring the production of blow molded plastic containers to detect a defect in any of the containers comprising the steps of:
-
a. loading a preform into a mold cavity at a loading station; b. introducing pressure fluid to an interior of the preform in the mold cavity to form a blow molded plastic container while moving the mold cavity along a generally circular path; c. acoustically sensing a defect sound resulting from the pressure fluid escaping from the interior of the container being formed at a position adjacent the path and within a portion of the path during which preblow air is being applied to the preform in the mold cavity; and d. generating a control signal in response to the sensed defect sound. - View Dependent Claims (12, 13, 14, 15, 16)
-
-
17. An apparatus for monitoring the production of blow molded plastic containers formed by introducing pressure fluid to an interior of a preform in a mold cavity comprising:
-
a columnator positioned adjacent a mold cavity during the introduction of preblow air to a preform in the mold cavity to form a container, said columnator having an input end directed toward the mold cavity; a sensor means being responsive a defect sound of the pressure fluid escaping from the interior of the container for generating an output signal, the defect sound being transmitted through said columnator; and means for generating a control signal in response to said output signal whereby a container rejecter receiving said control signal rejects the container. - View Dependent Claims (18, 19, 20)
-
Specification