Abstract:
A rotating brush, mounted on either the outside or the inside of a rotary intake drum, to brush debris from the surface of the drum. The debris is collected in a holding bin located under the brush. The system uses a collector to remove debris from the holding bin when it is filled. In this way, debris is removed completely from the intake, rather than merely brushing it from the drum into the water flow, where it is immediately sucked onto the drum again. The brush rotates the drum as it turns on the surface. This action flicks the debris from the drum into the holding bin. This action automatically removes debris as the drum is working. Other features of the device include a framework for placing and operating the drum and the collection system.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to rotary drum strainers and particularly to rotary drum strainers that are self-cleaning. 
     2. Description of Related Art 
     Strainers are used in association with motor-driven pumps that suck water out of outdoor pits, reservoirs, streams, ponds, and the like, for mining, irrigation, or watering purposes. Typically, strainers are connected to pumps by a long intake conduit or hose that extends from the strainer in the body of water to a pump on land. Strainers are placed on the end of the intake to prevent debris, small stones and other objects from being sucked into the pump while pumping. As a pump is operated, the strainer may be covered with leaves and other large pieces of debris that are drawn to the strainer. This material eventually blocks the strainer openings, thereby reducing the flow of water through the strainer, possibly even shutting it off entirely. Once plugged, the strainer must be removed from the water and cleaned. During this time, no water can be pumped. Depending on the water source, this cleaning operation can be frequently required, making the pumping operation inefficient. 
     To overcome this problem, self-cleaning strainers have been developed. For example, U.S. Pat. Nos. 5,275,656, 5,108,592, and 4,822,486 use water fed from the pressure side of the pump to rotate and clean the screen. This water washes debris from the screen while the pump is in operation. However, the volume of water delivered to a pump is reduced using this method because some water is redirected to the strainer. Moreover, this method of cleaning and rotating the screen depends on pump pressure being high enough to effectively clean and rotate the screen. Finally, although the devices clean the strainer, the debris removed from the strainer remains in the body of water near the strainer. This debris is then pulled right back onto the strainer where it must be washed off again. Thus, this method is not efficient. 
     U.S. Pat. No. 4,261,822 illustrates a drum-like screen that is placed horizontally in a ditch and held partially out of the water by attached legs. It is designed to be transportable. However, it is designed to be used primarily in only irrigation ditches. Although this device is an improvement over the others, it benefits from two advantages of controlled operating circumstances. First, because it is intended for use in irrigation ditches, the movement of water can be controlled. Second, the water level can be controlled. Thus, the strainer may rest on the ditch floor and does not have to be raised or lowered with changes in water level. These conditions are not often found in many bodies of water. 
     BRIEF SUMMARY OF THE INVENTION 
     The instant invention overcomes the problems and limitations of the previously mentioned devices. It is an object of this invention to provide a rugged, self-cleaning rotary intake filter that can be transported and quickly set up for adverse conditions in a variety of water bodies. 
     It is another object of the invention to provide a simple, effective and efficient way of rotating and cleaning the screen. 
     It is yet another object of the invention to provide a means to carry the screen during transport, and to place the screen for operation. 
     It is yet another object of the invention to provide a means whereby the invention can be suspended from a lifting source such as a boom extending from the pump frame. 
     It is a further object of the invention to provide a means for flotation whereas the invention floats at the correct level in the water for efficient operation in different depths of water. 
     It is yet a further object of the invention to provide a means for containment of debris being cleaned off the screen 
     It is a further object of the invention to provide a means for supporting the invention so that the device may be placed on the floor of the water body if so desired. 
     With these objects in mind, the invention is a rotary water intake drum that has a self-cleaning system attached. This system uses a rotating brush, mounted on the outside of a drum, to brush debris from the surface of the drum. The debris is collected in a holding bin located under the brush. The system uses a collector to remove debris from the holding bin when it is filled. In this way, debris is removed completely from the intake, rather than merely brushing it from the drum into the water flow, where it is immediately sucked onto the drum again. As the brush rotates, the drum rotates. As the drum rotates, the flexible bristles on the brush flick the debris from the screen on the drum into the holding bin. This action automatically removes debris as the drum is working. Other features of the invention include a framework for placing and operating the drum and the collection system. Moreover, this system is designed for use in different types of water and at different depths. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the invention and the auxiliary lifting and operating station. 
     FIG. 2 is a perspective view of the invention. 
     FIG. 3 is a side cut-away view of the invention. 
     FIG. 4 is a front view of the invention, showing two floats installed. 
     FIG. 5 is a partial cut-away perspective view of the invention with attached floats. 
     FIG. 6 is a perspective view of the device showing an embodiment that uses manual control of the cleaning elements. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to FIG. 1, the preferred embodiment of rotary self-cleaning drum strainer  10  is shown. FIG. 1 also shows a system from which strainer  10  may be suspended. The system AA has a skid A, from which a pump B, an engine C and a fuel tank D are mounted. Upper framework E provides a place for boom F to be mounted. A chain G provides support and holds adjustable boom F at the correct angle for operation. A winch H is provided on upper framework E and its cable extends over boom pulley I and to a lifting eye  12  of strainer  10 . A flexible conduit J allows strainer  10  to be raised or lowered independently of the system AA. 
     The weight of the skid A, pump B, engine C, fuel tank D, and upper framework E, is more than sufficient to suspend strainer  10 , from boom F. Picking eyes K are provided on top of upper framework E in order to lift entire system AA along with screen drum  10  to a desired location. A piece of equipment such as a loader or an excavator is normally used for this procedure. System AA is placed so that skid A is on solid ground and strainer  10  is hanging over a body of water. Winch H is operated to lower strainer  10  to the correct level in the liquid. 
     The FIGS. 1,  2 , and  3 , show the rotary self-cleaning drum strainer  10  that includes a main frame  44  upon which all other components of the strainer  10 , are mounted. A fixed plate  46 , legs  50 , and screen guard  52 , make up the rest of the main frame  44 . The fixed plate  46  is made generally of flat plate material and in the preferred embodiment is made of {fraction (3/16)}-inch thick, flat steel plate. A hole is disposed in the lower portion of plate  46 . A threaded pipe adapter  54  is welded to the perimeter of the hole. The threaded adapter  54  makes a fluid connection from the inside of a screen drum  30 , described later, to conduit J. Conduit J makes fluid connection to the intake of the liquid pump B. In most cases, a foot valve (not shown) is placed in the line between the threaded adapter  54  and conduit J. The foot valve keeps the liquid pump from losing its “prime” when not in use. The pipe threads of adapter  54  allow for common connections. Fixed plate  46  is generally circular in shape except at the top, where the plate extends above the circular diameter. This extension has a hole in it that serves as a picking eye  12 , from which strainer  10  may be suspended as described above. In the preferred embodiment, fixed plate  46  has support members  14  of suitable size welded to it in order to make the plate rigid. 
     In the center of the circular shaped fixed plate  46  is a mounting hole from which a bearing thrust plate  42   a  is attached. A frame arm  48  is welded at one end to the top of the circular shape of plate  46  and below the picking eye  12 . Frame arm  48  extends away and perpendicular from plate  46 , along the top of the drum  30 . At the end of the drum  30 , the frame arm  48  forms a 90-degree angle. The frame arm  48  then runs parallel with plate  32  until it reaches the point where it is in axial agreement with bearing  42   a  in fixed plate  46 . At this point, a mounting plate  16  is welded to the frame arm  48  where a mounting hole is formed to accept bearing thrust plate  42 . See FIG.  3 . 
     The cylindrically shaped screen drum  30  is mounted horizontally between bushings  42  and  42   a  by a central support tube  38 , as shown in FIG. 3. A central shaft  40  is installed in the support tube  38 . The shaft  40  passes through bushings  42  and  42   a  as shown. Screen drum  30  has an end plate  32  to cap one end of the horizontal screen and an open end hub  34  at the opposite end of drum  30  which faces fixed plate  46 . See FIG.  3 . The tube  38  extends slightly through the center of cap  32 . It is welded to cap  32  for support. Tube  38  is supported at the open end of drum  30  by a plurality of outwardly extending radial arms  33 , which connect, to a ring member  36 . The ring member  36  in the preferred embodiment is made of {fraction ( 1 / 4 )}-inch thick steel plate, being 48 inches outside, and 44 inch inside diameter. Open hub  34  having arms  33  extending from its center to ring member  36  is left open to allow liquid coming through the wall of drum  30  to enter threaded pipe adapter  54  which is connected to the pump B by the conduit J. Ring member  36  and end cap  32  are interconnected by a plurality of screen supports  37 . Together screen supports  37  and ring member  36  make up a cylindrically structured cage from which a screen element  20  is mounted. Screen supports  37  are generally made up of steel flat-bar of appropriate size. The flat bar is welded so that its thickness is facing the screen  20  to blind the least amount of screen and yet be structurally strong to support the screen  20 . The screen  20  may be formed by rolling a rectangular section of appropriate size into a circular shape; clamping the screen  20  against the hubs and screen supports; and then tack welding the screen to the hubs and screen supports. If desired, an angle iron may replace a flat-bar screen support to give extra area to tack weld the abutting screen edges at the screen joint. 
     Screen drum  30  is spaced a distance apart from the fixed plate  46  by thrust plate bearings  42  and  42   a . A seal  56  is provided to prevent debris from entering the drum  30  through this space. This debris can hinder the rotation of the drum  30 . It can also be sucked into pump B. The seal  56  is made of suitable material such as rubber. The fixed plate  46  is larger in diameter than the drum  30  to allow for the seal  56  to be bolted to the outer portion of the fixed plate  46 . The length of the seal  56  encircles the complete diameter of the drum  30 , therefore effectively sealing the space described above. 
     The screen element  20  is made of heavy gauge wire to be self-supporting between screen supports  37 . The specific details of the screen, such as screen thickness and the size of the holes depends on the particular size of strainer  10 , and the particular intended use for which the strainer  10  is designed. An example of preferred material for screen  20  is a mesh with approximately 4 to 6 meshes per inch and approximately 11-gauge wire. 
     A cylindrically shaped brush  60  is mounted to be in mesh with and parallel to screen drum  30 . Brush  60  has a centrally disposed shaft  61  extending further on each end then the brush. A pillow block bearing  63  placed at each end of shaft  61  provides a rotatable mounting for brush  60  to a brush frame  62 . Shaft  61  extends through and beyond pillow block bearing  63  at the front end of the strainer  10  (at plate  46 ). The shaft  61  has slot in it to accept a key for a drive unit, which can be placed on shaft  61 . Drive units are described in detail below. 
     Brush frame  62  has two extension arms  64  and a cross member  65 . Cross member  65  is welded between the extension arms  64  to make a rigid U-shaped frame, as shown. The pillow block bearings  63  that support the brush  60  are attached to the extension arms  64  by bolts. Brush  60  is mounted to keep brush bristles from making contact with cross member  65 . The extension arms  64  are attached to the strainer by bolts. The forward extension arm bolts to a mounting hole in fixed plate  46  and the rear extension arm bolts to a tab  66  located on frame arm  48 . See FIG.  2 . 
     A washer is placed between each extension arm and its respective mounting hole to serve as a spacer, allowing free movement of brush frame  62 . A lock nut is provided on each bolt in order to snug but not tighten the bolt to allow free movement of frame  62 . 
     The brush  60  is of the long, moderately stiff, bristle type. The brush  60  is slightly shorter than the drum  30  to keep the bristles from damaging the rubber seal,  56 . 
     A catch hopper  68  is located parallel to and just below the brush  60 . The catch hopper  68  is a generally trapezoidal box, being wider at its front edge, where debris is received from the brush  60  than its back. The hopper  68  is approximately as deep as the diameter of the brush  60 . The end plates of the hopper each have a shaft  80  welded to them. In the preferred embodiment, these shafts are close to the back plate and approximately in the middle of the width of the end plates. These shafts  80  act as a pivot point for mounting the hopper  68  to the frame. Two hopper support arms  69  are welded to the main frame  44 . Each support arm has a slot in which the shafts  80  are attached. The shaft at the fixed plate  46  side extends past the mounting arm  69  and has a slot in it to accept a key so a flexible coupler such as a u-joint can be attached. See FIG.  6 . 
     Four legs  50  are attached to the main frame  44  as shown. The legs  50  are attached using conventional means, such as bolts or welding. The front legs are attached to the bottom of fixed plate  46 . The two rear legs are attached to the frame arm  48 . See, e.g., FIG.  4 . The legs are support the strainer  10  and allow it to rest on the water body floor while maintaining enough space between the drum and the floor to allow the drum  30  to turn freely. 
     A screen guard  52  is attached to legs  50  by bolts. Screen guard  52  has two side frame pieces extending from a fixed plate leg to a frame arm leg and being bolted to each. Four cross members are extended to, and are welded to side frames. Cross members can be made from half inch reenforcing bar (rebar) or similar material. Side frames can be made from angle iron. 
     The preferred embodiment uses a screen that has an approximately 30 inch axial dimension and a diameter of approximately 48 inches. The threaded pipe adapter is approximately 8 inches in diameter. 
     It is understood that when the assembly of parts are described as welded that they may also be made to bolt together for shipping or manufacturing reasons. 
     A flotation device can be used to adjust the level of the strainer  10  in one of several ways. Flotation can be installed either internally or externally or in a combination of both. Referring now to FIG. 5, an internal flotation body  31  is built inside of rotating drum  30 . The flotation body  31  is a cylindrical shaped body, smaller in diameter and shorter in length than drum  30 , so as not to interfere with water flowing through screen and into inlet conduit. The internal flotation body  31  can be built of a sufficient size to float entire invention  10 . It can also be built of a sufficient size to only float rotating drum  30 , thereby relieving the weight of the drum  30  on bearings,  42  and  42   a . Main frame  44  also may have flotation bodies  47   a  and  47   b  formed into the fixed plate  46 , and on frame arm  48  and frame arm legs  50  respectively. Built in body  47   a  on fixed plate  46  is of sufficient size and located in a manner to float the weight of fixed plate and its immediate adjoining parts. The built in body  47   b , attached to the frame arm  48  and frame arm legs  50 , is of a sufficient size to float its end of strainer  10 . All three bodies together float invention  10  approximately one-half out of the water, while inlet conduit J is sufficiently submerged below water. Flotation cavities are also matched in size to put a slight tilt on strainer  10  whereas floatation body  47   b  is slightly more submerged than the fixed plate end. The reason for this is that generally a foot valve is attached to adapter  54 . A foot valve works best when at an angle to allow the weight of the flapper to close the valve thereby keeping a prime in the pump. Other flotation methods are shown in FIG. 4, where sealed containers are attached to an adjustable framework. The framework has two U-shaped frames  72  one mounted on each side of strainer  10 . They are attached to the central shaft  40 , Which passes through holes disposed at each end of U-shaped framework. The U-shaped arms have a peg disposed on each outer comer from which a stiff arm  74  is attached. Stiff arms  74  are kept on the pegs by pins or similar fasteners. A plurality of holes is placed at the opposite end of the stiff arms  74 . The length of the arms  74  can be adjusted by choosing a different hole to attach the arms  74  to the fixed plate  46  and frame arm  48 . 
     From the outside of the U frame, a flotation device can be attached in a number of ways. For example, floats can be welded to the U-frame that fits sealed flotation containers. Floats  100  can be strapped, tied, wired, welded, or other way to the U-frame of the proper size to float strainer  10 . The submersion depth of strainer  10  can be changed by adjusting stiff arms  74 . Floats can be common containers such as 55 gallon drums, buoys, fabricated containers, foam-filled containers, and ridged foam just to name a few. The size of the flotation devices depends on the size and weight of the strainer  10  and the expense of manufacturing. The strainer  10  can be manufactured and sold with or without flotation devices attached. Any of the above-mentioned flotation attachments can be sold and manufactured separately as an attachment to the strainer as well. 
     Operation 1 
     The operation of the preferred embodiment is now described with reference to figures land  6 . When the strainer  10  is placed on the water body floor on its legs  50  approximately ½ to ⅓ of the screen drum  30  is above the water. This allows for threaded pipe adapter  54  to be well submerged since it is mounted on the lower portion of plate  46 , while the brush  60  and hopper  68  are above the water line. The brush  60  is of a long, moderately stiff, bristle type. When the brush  60  is rotated and the bristles come in contact with the screen drum  30  they bend backward from the turning force and the weight of the brush  60  and frame  62 . 
     The pressure and rotating force applied by the bristles in turn rotates screen drum  30 . As the bristles come off the drum  30 , they flex back into their normal straight position. If the bristles contact any debris adhered to the drum  30  they “flick” debris that was adhered to the drum  30  into the hopper  68  as they flex back into their normal position. When hopper  68  becomes full, the debris may be either manually removed. The hopper may be also dumped from shore by a dumping handle  76  extension from the shaft of the hopper described above. See FIG. 6. A flexible coupling such as a U joint is connected to the hopper shaft to dump handle  76 . A floating hopper  78  may be positioned under the hopper  68  by an extending handle  80  from the shore. Hopper  68  may then be dumped into floating hopper  78 . After hopper  68  has been dumped, it is rotated back into its operation position, floating hopper  78  is pulled to shore, and debris is disposed of. This ensures that the debris is removed from the water, which reduces the need to empty the hopper. 
     Operation 2 
     A system such as system AA described above may be used to suspend strainer  10  at the level desired in case of changing liquid levels. In this system, the simplest form of rotating the brush is by attaching a flexible joint such as a U-joint to the keyed shaft  61 . From the opposite side of the U-joint, a shaft  82  is employed. The shaft  82  may extend to the shore where a person may rotate the shaft from its T handle attached to the end of the shaft. See FIG.  6 . The shaft may be placed in a cradle such as shown in FIG.  6 . The cradle allows the shaft to slide in and out and rotate freely. A power drive unit such as a hydraulic or electric motor  101  may be directly coupled to the keyed shaft  61  and mounted to a mount attached to brush frame  62 . Flexible power lines such as hydraulic hoses or sealed electrical lines may be strapped to conduit J to reach the motor drive unit from a power source. The power drive unit  101  may also be mounted to a frame such as on system AA. In this case, a splined shaft would reach from the keyed brush shaft to the power drive motor. See FIG.  7 . 
     The power drive motor  101  may be set up to operate the brush  60  continually or intermittently when the controls are manually operated by an operator. The power drive motor may also be made to operate at preset time intervals. 
     The present disclosure should not be construed in any limited sense other than that limited by the scope of the claims having regard to the teachings herein and the prior art being apparent with the preferred form of the invention disclosed herein and which reveals details of structure of a preferred form necessary for a better understanding of the invention and may be subject to change by skilled persons within the scope of the invention without departing from the concept thereof.