Method and apparatus for testing end closures

{
  "publication_number": "US3875790A",
  "country": "US",
  "kind": "A",
  "title": "Method and apparatus for testing end closures",
  "abstract": "Improved method and apparatus for testing for leakage with a pressurized gas media, a container end closure having a displaceable member sealed to the end closure by a distensible sealant material, the improved method comprising effecting a separation between the end closure and displaceable member to distend the sealant material and to expose the sealant material to the pressurized gas, to test the sealant material and the seal it provides for leakage. In the improved apparatus, means for effecting the separation are provided in a test chamber, the lower chambered member thereof including a solid center chuck and a vertically reciprocable spring-mounted pilot ring peripheral to the chuck, and the vertically moveable upper chambered member thereof including an engaging surface for engaging and moving an end closure seated on the pilot ring downward while downward movement of the displaceable member is resisted by the center chuck.",
  "claims": [
    "1. In the method of testing an end closure for leakage, of the type including the steps of providing a test chamber sealedly divisible into first and second sections by an end closure placed therein, placing an end closure therein, injecting a testing medium into the first section, and sensing change in the second section due to leakage of the medium through the end closure, the improvement for testing an end closure having a displaceable member sealed to the end closure by a distensible sealant material, which comprises: effecting a separation between the end closure and displaceable member to distend the sealant material while the one section is gas pressurized and to expose the sealant material to the pressurized gas to test the sealant material and the seal it provides for leakage.",
    "2. The improved method of claim 1 wherein the separation effecting step is effected by holding the displaceable member in a substantially fixed position and moving the end closure away from it.",
    "3. The improved method of claim 2 wherein the holding step is effected by providing a resisting surface under the displaceable member.",
    "4. In the method of testing an end closure for leakage, of the type including the steps for providing a test chamber sealedly divisible into first and second sections by an end closure placed therein, placing an end closure therein, injecting gas pressure into the first section, and sensing pressure buildup in the second section due to leakage through the end closure, the improvement for testing an end closure having an aperture therein and having a displaceable member closing the aperture and sealed to the end closure by a distensible sealant material, which comprises: effecting a separation between the end closure and displaceable member to distend the sealant material while the one section is gas pressurized and to expose the sealant material to the pressurized gas to test the sealant material and the seal it provides for leakage.",
    "5. In the method of testing an end closure for leakage, of the type including the steps of providing a test chamber sealedly divisible into first and second sections by an end closure place therein, placing an end closure therein, injecting high-pressure gas into the first section, and sensing pressure buildup in the second section due to leakage through the end closure, the improvement for testing a button down end closure having a displaceable button and a distensible sealant material sealing the button to the end closure, which comprises: effecting a separation between the end closure and the button to distend the sealant material while the one section is highly pressurized and to expose the sealant material to the high-pressure gas to test the sealing material and the seal it provides for leakage.",
    "6. The improved method of claim 5 wherein the separation effecting step is effected by holding the button in a substantially fixed position and moving the end closure away from it.",
    "7. The method of claim 6 wherein the separation effected is less than about 0.005 inch.",
    "8. The improved method of claim 7 wherein the holding step is effected by providing a resisting surface under the button.",
    "9. In an apparatus for testing an end closure for leakage of the type which includes a test chamber sealedly divisible into first and second sections by an end closure placed therein, means for injecting pressurized gas into the first section, and sensing means for detecting a pressure change in the second section due to leakage through the end closure, the improvement in the test chamber for testing an end closure having a displaceable member sealed thereto by a distensible sealant material, which comprises: means connected to the test chamber for effecting a separation between the end closure and its displaceable member to distend the sealant material while the test chamber is gas pressurized and to expose the sealant material to the pressurized gas to test the sealant material and the seal it provides for leakage.",
    "10. The improved apparatus of claim 9 wherein the means for effecting the separation include resisting means for holding the displaceable member in a substantially fixed position relative to the end closure and moving means for moving the end closure away from the displaceable member.",
    "11. The improved apparatus of claim 9 wherein the sealant material is distended less than about 0.005 inch.",
    "12. The improved apparatus of claim 10 wherein the sealant material is distended less than about 0.005 inch.",
    "13. In an apparatus for testing an end closure for leakage, of the type which includes a test chamber sealedly divisible into first and second sections by an end closure placed therein, means for injecting high-pressure gas into the first section, and sensing means for detecting a pressure increase in the second section due to leakage through the end closure, the improvement in the test chamber rendering it utilizable for testing a button down end closure having a displaceable button sealed to the end closure by a distensible sealant material, which comprises: means connected to the test chamber for effecting a separation between the end closure and its button to distend the sealant material while the test chamber is highly-pressurized to expose the sealant material to the high-pressure gas to test the sealant material and the seal it provides for leakage.",
    "14. The improved apparatus of claim 13 wherein the end closure to be tested has an aperture rim defining an aperture therein, the button closes the aperture, the sealant material is a plastisol which surrounds and seals the button rim and the aperture rim, and the separation effecting means includes resisting means for holding the button rim in one position relative to the aperture rim and moving means for moving the aperture rim away from the button rim.",
    "15. The apparatus of claim 14 wherein the separation effected is less than 0.005 inch.",
    "16. The apparatus of claim 14 wherein the test chamber is formed by a moveable upper chambered member and a fixed lower chambered member, the improvement further comprising the resisting means including a center chuck fixed to and within the lower chambered member, said center chuck having an upper resisting surface for resisting downward movement of the button when the rest of the end closure is moved downward, and the moving means including an upwardly-biased pilot ring peripheral to the center chuck and spring-mounted within the lower chambered member, said pilot ring having a seat for seating a peripheral portion of said end closure thereon, and engaging means on said upper chambered member for engaging an end closure placed on the pilot ring and for moving the end closure and pilot ring downward, the resisting means and moving means cooperating to effect the separation by moving the end closure downward relative to and away from the button."
  ],
  "cpc": [
    "G01M 3/2869",
    "G01M 3/26"
  ],
  "assignees": [
    "AMERICAN CAN CO"
  ],
  "filing_date": "1974-03-26",
  "publication_date": "1975-04-08",
  "grant_date": "1975-04-08",
  "priority_date": "1974-03-26",
  "application_number": "US-45483774-A",
  "family_id": "23806312",
  "citations": [
    "US2696107A",
    "US3499314A"
  ]
}