Filter unit with cleaning attachment

• US 3,898,414 A
• Filed: 05/06/1974
• Issued: 08/05/1975
• Est. Priority Date: 05/06/1974
• Status: Expired due to Term

• Current Assignee: First Union National Bank Of North Carolina
• Original Assignee: Clyde W. Hawley
• Inventors: Hawley, Clyde W.
• Primary Examiner(s): Lutter, Frank W.
• Assistant Examiner(s): Prunner, Kathleen J.
• Application Number:
  US05/467,105
• Time in Patent Office: 456 Days
• Field of Search: 55/272,282,283,289,295-297,298,299,301,304,305,385,420,428,467,498,510 210/396 219/72
• US Class Current: 219/72
• CPC Class Codes: B01D 46/2411 Filter cartridges
• CPC Class Codes: B01D 46/26 rotatable
• CPC Class Codes: B01D 46/521 using folded, pleated material
• CPC Class Codes: B01D 46/76 involving vibrations
• CPC Class Codes: B08B 15/04 from a small area, e.g. a tool removing chips B23Q11/0042

Abstract

A cleaning system for a filter unit used in connection with a plurality of independently operable welding guns in which the suction chamber surrounding the tip of each gun is connected via sections of flexible hose and a flap valve to a main dust collecting pipe or manifold to which the inlet duct of the filter unit is attached. A source of suction is connected to the outlet duct of the filter unit so as to draw objectionable smoke and fumes that are generated in the area of the welds through the filter unit. This filter comprises a cylindrical housing containing a conventional radial-fin filter cartridge. A plurality of straps are fastened to a shaft, that is journaled in the upper end of the housing for rotation from the exterior thereof, either manually or by a motor. The straps extend downwardly into the space between the housing and the cartridge. Each strap carries on its outer surface a flexible wiper, which engages the inside of the housing, and on its inner surface a plurality of vertically-spaced, flexible tabs, which project into the spaces between adjacent pleats in the cartridge. To clean the cartridge, the shaft is rotated so that the tabs knock the caked dust from the cartridge pleats as they pass or flex thereover, at the same time that the flexible wipers sweep dust from the inside surface of the housing.

Claims

1. A filter comprising a housing having a fluid inlet and a fluid outlet, means connecting said outlet to a vacuum source to draw fluid through said housing from said inlet, a porous pleated filter cartridge removably secured in said housing with its periphery spaced from the inside wall of said housing and between said inlet and said outlet and having an axial bore closed at one end and connected at its opposite end to said outlet, a rotatable support mounted in said housing coaxially of said bore, a plurality of axially-extending, rigid straps mounted on said support around the outside of said cartridge in the space between the periphery of said cartridge and the inside wall of said housing, each of said straps having a plurality of tabs mounted in spaced relation longitudinally along the strap, each of said tabs projecting part way into the space between adjacent pleats in said cartridge, whereby upon rotation of said support, said tabs flex said pleats thereby to jar caked particles from the pleats, and drive means on the exterior of said housing connected to said support to effect rotation of said support relative to said housing.

2. A filter, comprising a housing having a fluid inlet and a fluid outlet, means connecting said outlet to a vacuum source to draw fluid through said housing from said inlet, a porous, pleated filter cartridge removably secured in said housing between said inlet and said outlet to filter particles from the fluid passing therebetween and having an axial bore closed at one end and connected at its opposite end to said outlet, a rotatable support mounted in said housing coaxially of said bore, a plurality of spaced tabs mounted on said support around the outside of said pleated cartridge, each of said tabs projecting part way into the space between adjacent pleats in said cartridge, whereby upon rotation of said support said tabs flex said pleats to jar caked particles therefrom, and drive means on the exterior of said housing connected to said support to effect rotation of said support relative to said housing, said support comprising a plurality of axially-extending straps arranged in angularly spaced relation around the outside of said cartridge parallel to the pleats thereof, said tabs being secured to said straps at spaced points therealong, and an elongate, flexible wiper means mounted on each of said straps to have sliding contact with the inside wall of said housing to sweep particles therefrom during rotation of said support.

3. A filter as defined in claim 2, wherein a sump is positioned beneath the lower end of said housing beneAth said cartridge to receive particles jarred loose from the cartridge and housing by said tabs and wiper, respectively.

4. In a filter system including a plurality of welding guns of the type in which a vacuum chamber in each gun opens on the welding tip thereof to draw smoke and particles from the vicinity of a weld during use of the gun, a manifold, means connecting the vacuum chamber of each gun to said manifold, comprising a first duct connected at one end to an opening in said manifold, a valve connected to the opposite end of said duct, a second duct connected at one end to the vacuum chamber on one of said guns, means for releasably connecting the opposite end of said second duct to said valve from communication thereby with said manifold, and means operative automatically to close said valve when said opposite end of said second duct is disconnected therefrom, and a filter unit comprising a housing having an inlet and an outlet, means connecting the inlet of said housing to said manifold, means for applying a vacuum to the outlet of said housing to draw smoke and particles from the vacuum chamber of each gun through its associated ducts and valve, when open, into said housing, a porous, pleated filter cartridge removably mounted in said housing to cover said inlet to filter out particles drawn into the housing by the vacuum means, and means for cleaning accumulated particles from the pleated surfaces of said cartridge without removing the cartridge from said housing.

5. A filter system as claimed in claim 4, wherein said means for cleaning said cartridge comprises a plurality of spaced tabs mounted around the outside of said cartridge and having portions thereof projecting part way into the spaces between adjacent pleats in the cartridge, means for detecting the pressure differential between said inlet and said outlet when a vacuum is applied to said inlet, and drive means connected to said tabs and operative, when said pressure differential exceeds a predetermined value, automatically to revolve said tabs about said cartridge to drag the projecting portions of said tabs successively across the peaks of pleats in the cartridge to jar loose any particles caked thereon.

6. A system as defined in claim 5, wherein said drive means comprises a support rotatably mounted in an opening in one end of said housing, said outlet comprises a stationary pipe projecting coaxially through an axial bore in said support into said one end of said housing, said cartridge has an axial bore closed at one end and releasably attached at its opposite end to said pipe to be supported thereby in the housing with its pleats extending vertically, a plurality of straps are attached to said support and project vertically downwardly in angularly spaced relation around the outside of said cartridge, between said cartridge and said housing, and a plurality of said tabs are attached to each of said straps at spaced points therealong to project radially inwardly into the spaces between adjacent pleats on said cartridge.

7. In a filter system including a plurality of welding guns of the type in which a vacuum chamber in each gun opens on the welding tip thereof to draw smoke and particles from the vicinity of a weld during use of the gun, a manifold, a first duct connected at one end to an opening in said manifold, a valve connected to the opposite end of said duct, a second duct connected at one end to the vacuum chamber on one of said guns, means for releasably connecting the opposite end of said second duct to said valve for communication thereby with said manifold, means operative automatically to close said valve when said opposite end of said second duct is disconnected therefrom, a filter unit comprising a housing having an inlet and an outlet, means connecting the inlet of said housing to said manifold, means for applying a vacuum to the outlet of said housing to draw smoke and particles from said vacuum chamber on said one gun through said ducts and said valve, when open, into said housing, a porous filter cartridge removably mounted in said housing to enclose said inlet to filter out particles drawn into the housing by the vacuum means, said cartridge having thereon a plurality of spaced, parallel pleats upon which particles drawn into said housing settle, a plurality of spaced tabs mounted around the outside of said cartridge, said tabs having portions thereof projecting part way into the spaces between adjacent pleats in the cartridge, means for detecting the pressure differential between said inlet and said outlet when a vacuum is applied in said inlet, drive means connected to said tabs and operative, when said pressure differential exceeds a predetermined value, automatically to revolve said tabs about said cartridge to drag the projecting portions of said tabs successively across the peaks of pleats in the cartridge to jar loose any particles caked thereon, said drive means comprising a support rotatably mounted in an opening in one end of said housing, said outlet comprising a stationary pipe projecting coaxially through an axial bore in said support into said one end of said housing, said cartridge having an axial bore closed at one end and releasably attached at its opposite end to said pipe to be supported thereby in the housing with its pleats extending vertically, and a plurality of rigid straps attached to said support and projecting vertically downwardly in angularly spaced relation around the outside of said cartridge, between said cartridge and said housing, a plurality of said tabs being attached to each of said straps at spaced points therealong to project radially inwardly into the spaces between adjacent folds on said cartridge, each of said straps having a cleaning strip attached thereto to the opposite side of the strap from its tabs in position to engage the inside wall of said housing to sweep over and clean the same during rotation of said support.

8. A system as claimed in claim 7, wherein a receptacle is mounted in said housing beneath said cartridge to receive dust and the like wiped off the cartridge and said wall.