METHOD FOR INSPECTING FILTERS

• US 3,693,406 A
• Filed: 01/20/1971
• Issued: 09/26/1972
• Est. Priority Date: 01/26/1970
• Status: Expired due to Term

• Current Assignee: Benjamin F. Tobin III
• Original Assignee: Benjamin F. Tobin III
• Inventors: Tobin, Benjamin F. III
• Primary Examiner(s): Swisher, S. Clement
• Application Number:
  US05/108,139
• Time in Patent Office: 615 Days
• Field of Search: 73/38,40,45.5 134/149,152,168
• US Class Current: 73/38
• CPC Class Codes: B01D 41/04 of rigid self-supporting filtering material
• CPC Class Codes: G01M 3/04 by detecting the presence of fluid at the leakage point

Abstract

Method and apparatus are described for washing hollow cylindrical engine air cleaners or filter elements on inside and outside surfaces. After the washing operation and before drying the filters are inspected by directing a forceful flow of water heavily aerated with entrained bubbles of air against the filter surface. Visual observation of bubbles passing through the filter element provides rapid and reliable detection of leaks through the filter.

Claims

1. A method of inspecting an air filter or the like having a liquid wettable porous membrane comprising the steps of:

directing a forceful flow of aerated liqUid against one face of the membrane; and

observing the opposite surface of the membrane for the presence of gas bubbles in liquid flowing therethrough.

2. Apparatus for inspecting an air filter or the like comprising:

means for rotating a filter for visual inspection; and

means for directing a flow of water having a large number of bubbles of air entrained in the water against a surface of the air filter.

3. Apparatus as defined in claim 2 wherein the means for rotating comprises:

a pair of almost horizontal, parallel, spaced apart rollers; and

means for rotating at least one of the rollers.

4. Apparatus as defined in claim 3 wherein the means for directing a flow of water has sufficient force to pass bubbles of air through leaks in the filter and insufficient to overcome surface tension of liquid in a porous filter.

5. Apparatus as defined in claim 4 wherein the means for directing a flow of water comprises a hand held nozzle.