Fluid strainer and method of converting the same between motorized and manual modes with pressure-sensitive switch

Abstract

An improved fluid-strainer is provided which makes provision for improved methods of converting the same between motorized and manual modes. Included in the fluid strainer is a gear motor housing for facilitating the conversion as well as inspection and removal means. Also provision is made for flushing of the fluid strainer so as to avoid cycle restart.

What is claimed is: 
     
       1. A fluid strainer apparatus adapted to be coupled to a fluid line for removing solid debris suspended in fluid travelling in the fluid line, said strainer comprising: a housing assembly defining a sidewall of a chamber an inlet means couplable to the fluid line for supplying fluid to said strainer and at least an outlet means for discharging strained fluid from said housing assembly;   fluid strainer means including a screen rotatably mounted in said housing in said chamber adjacent said outlet means;   at least a scraper blade mounted in said housing assembly in such a manner that a scraping edge thereof is adjustable spaced in close proximity to said screen so as to remove solids from said screen when the latter is rotated relative to said edge;   said housing assembly including an inspection means defined by a sealable opening in said sidewall communicating with said chamber, said opening being sealingly closed by an enclosure means, said opening being sized and located so as to enable removal of said enclosure means to open said opening, removal of debris from said screen and said housing assembly and adjustment of said adjustably mounted scraping blade so that the spacing of said blade edge from said screen can be adjusted.   
     
     
       2. The strainer of claim 1 wherein said enclosure means has a portion which sealingly fits snugly in said opening and includes an O-ring on a periphery of said portion so as to seal said inspection opening. 
     
     
       3. A fluid strainer apparatus adapted to be coupled to a fluid line for removing solid debris suspended in fluid travelling in the fluid line, said strainer comprising: a housing assembly defining an inlet means couplable to the fluidline and at least an outlet means for discharging the fluid;   fluid straining means rotatably mounted adjacent said outlet means in said housing assembly;   at least a scraper blade mounted in said housing assembly in such a manner that a scraping edge is in close proximity to said straining means so as to remove solids therefrom when the latter is rotated relative to said edge;   said straining means including a cylindrical screen rotatably mounted in said housing assembly, a rotatable drive shaft journalled in said housing assembly and coupled to said screen so as to rotate said screen in response to rotation of said shaft;   motor means releasably coupled to said apparatus and operable for rotatably driving said shaft and said screen so that said scraper blade can clean said screen;   said motor means includes a gear housing comprising a motorized worm gearing unit having a worm rotatably driven by a drive motor, a hollow shaft worm gear in said housing meshingly engages said worm, said worm gear being coaxially coupled to and rotatable with said drive shaft, said housing including a pair of gear plates each providing a journalled surface extending towards each other for rotatably supporting said worm gear for rotation, at least one of said gear plates being threadedly connected to said housing assembly; and   one of said plates enclosing an end of said hollow worm gear, wherein said gear housing completely encloses said drive shaft.   
     
     
       4. The fluid strainer of claim 3 further including sealing means housed in an open end of said hollow worm gear for sealingly protecting said worm and said worm gear. 
     
     
       5. The fluid strainer of claim 4 wherein said strainer housing assembly includes an enlarged opening which facilitates manual removal of debris from said screen and also allows adjustment of said scraping blade so as to adjust the spacing of said blade edge from said screen. 
     
     
       6. The fluid strainer of claim 3 wherein one of said gear plates of said gear housing is removably attached to said strainer housing assembly. 
     
     
       7. A method of converting a fluid strainer from manual operation to motorized operation comprising the steps of: providing a fluid strainer apparatus adapted to be coupled to a fluid line for removing solid debris suspended in the fluid, wherein the strainer comprises a housing assembly defining a fluid inlet means and at least an outlet means for discharging the fluid, a fluid straining means which includes a cylindrical screen rotatably mounted in the housing assembly, a rotatable drive shaft journalled in the housing assembly and coupled to the screen so as to rotate the screen in response to rotation of the drive shaft, and a handwheel attached to an end of the drive shaft protruding from the housing assembly;   removing the handwheel from the shaft;   attaching a motor means to the housing assembly wherein the motor means includes a motorized worm gear unit having a worm rotatably driven by a motor, a hollow shaft worm gear meshingly engaging and driven by the worm, wherein the worm gear shaft is keyed to the protruding end of the drive shaft so as to be coaxially coupled to and rotatable with the drive shaft and with a housing assembly completely enclosing the drive shaft.   
     
     
       8. A method of converting a fluid strainer from motorized operation to manual operation comprising the steps of: providing a fluid strainer apparatus adapted to be coupled to a fluid line for removing solid debris suspended in the fluid, wherein the strainer comprises a housing assembly defining a fluid inlet means and at least an outlet means for discharging the fluid, a fluid straining means rotatably mounted in the housing assembly, a straining means which includes a cylindrical screen rotatably mounted in the housing assembly, a rotatable drive shaft journalled in the housing assembly and coupled to the screen so as to rotate the screen in response to rotation of the drive .Iadd.shaft; .Iaddend.   providing a motor means attached to an end of the drive shaft extending from the housing assembly wherein the motor means includes a motorized worm gear unit having a worm rotatably driven by a motor, a hollow shaft worm gear meshingly engaging and driven by the worm, with the worm gear shaft being keyed to the protruding end of the drive shaft so as to be coaxially coupled to and rotatable with the drive shaft and with a housing assembly completely enclosing the drive shaft;   removing the motor means from the drive shaft; and,   attaching a handwheel to the protruding end of the drive shaft.   
     
     
       9. In a method of automatically flushing a fluid strainer having a pressure sensitive switch operable for monitoring pressure differentials between a fluid inlet and a fluid outlet, wherein the strainer has a motorized rotatable screen and a scraping blade in close proximity therewith, and a motorized discharge valve operable for opening and closing a discharge outlet comprising the steps of: rotating the screen substantially throughout the opening and closing of the discharge valve;   and rendering inoperative the pressure sensitive switch during opening and closing of the discharge valve as well as for a preselected time period after closing of the discharge valve so that the switch does not operate to restart another discharge valve opening. .Iadd.   
     
     
       10.  A method of converting a fluid strainer form manual operation to motorized operation comprising the steps of: providing a fluid strainer apparatus adapted to be coupled to a fluid line for removing solid debris suspended in the fluid, wherein the strainer comprises a housing assembly defining a fluid inlet means and at least an outlet means for discharging the fluid, a fluid straining means which includes a cylindrical screen rotatably mounted in the housing assembly, a rotatable drive shaft journalled in the housing assembly and coupled to the screen so as to rotate the screen in response to rotation of the drive shaft, and a handwheel attached to an end of the drive shaft protruding from the housing assembly;   removing the handwheel from the shaft; and   attaching a motor means to the housing assembly wherein the motor means includes a motorized gear unit including a driving gear rotatably driven by a motor and being in meshing engagement with a driven gear, said driven gear including a passage for coaxially receiving a portion of the drive shaft protruding from the housing assembly, said driven gear being coupled to and rotatable with the drive shaft and with an additional housing assembly enclosing the drive gear, the driven gear, and the portion of the drive shaft protruding from the housing assembly and coaxially received by the passage of the driven gear. .Iaddend..Iadd.   
     
     
       11.  A method of converting a fluid strainer from motorized operation to manual operation comprising the steps of: providing a fluid strainer apparatus adapted to be coupled to a fluid line for removing solid debris suspended in the fluid, wherein the strainer comprises a housing assembly defining a fluid inlet means and at least an outlet means for discharging the fluid, a fluid straining means rotatably mounted in the housing assembly, a straining means which includes a cylindrical screen rotatably mounted in the housing assembly, a rotatable drive shaft journalled in the housing assembly and coupled to the screen so as to rotate the screen in response to rotation of the drive shaft;   providing a motor means attached to an end of the drive shaft that extends from the housing assembly wherein the motor means includes a motorized gear unit including a driving gear rotatably driven by a motor and being in meshing engagement with a driven gear, said driven gear including a passage for coaxially receiving a portion of the end of the drive shaft extending from the housing assembly, said driven gear being coupled to and rotatable with the drive shaft and with an additional housing assembly enclosing the drive gear, the driven gear, and the portion of the end of the drive shaft extending from the housing assembly and coaxially received by the passage of the driven gear;   removing the motor means from the drive shaft; and   attaching a handwheel to the protruding end of the drive shaft. .Iadd.   
     
     
       12.  A fluid strainer apparatus adapted to be coupled to a fluid line for removing solid debris suspended in fluid travelling in the fluid line, said strainer comprising: a housing assembly defining an inlet means coupled to the fluid line and at least an outlet means for discharging the fluid;   fluid straining means rotatably mounted adjacent said outlet means in said housing assembly;   at least a scraper blade mounted in said housing assembly in such a manner that a scraping edge is in close proximity to said straining means so as to remove solids therefrom when the latter is rotated relative to said edge;   said straining means including a cylindrical screen rotatably mounted in said housing assembly, a rotatable drive shaft journalled in said housing assembly and coupled to said screen so as to rotate said screen in response to rotation of said shaft;   motor means releasably coupled to said apparatus and operable for rotatably driving said shaft and said screen so that said scraper blade can clean said screen;   said motor means includes a gear housing comprising a motorized gearing unit including a driving gear in meshing engagement with a driven gear, said driving gear being driven by a drive motor and said driven gear including a passage for receiving the drive shaft therein, said driven gear being coaxially coupled to and rotatable with the drive shaft, said gear housing having spaced-apart plates, said plates having inwardly directed journalled surfaces for rotatably supporting the driven gear, at least one of the plates being connected to the housing assembly through detachable connecting means. .Iaddend.