Abstract:
The invention provides a fluid ejection apparatus configured for being mounted to a mixing tank in a position to eject a pressurized fluid to impinge the lower surface of a mixing agitator. The apparatus has a rod mounted for linear movement within in a body, a closing element being affixed to an end of the rod. A spring is mounted to the body within a lower section for biasing the rod and the closing element toward a closed position. An upper section is mounted to the body for discharging the pressurized fluid through an array of outlet channels.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to the field of equipment for cleaning the interior of tanks, and more particularly to a fluid ejection apparatus for cleaning a mixing device located in a tank. 
       BACKGROUND 
       [0002]    Many liquid products are a manufactured blend, or mixture, of several components. The components may each be a liquid or a powder, provided a major portion of the mixture is comprised of a liquid. Whether all of the ingredients are liquid or some are liquid and some are a powder, thorough mixing is required to achieve a desired uniform mixture. The mixing is typically accomplished by use of a rotating agitator, e.g. a shaft mounted device having multiple blades. 
         [0003]    The completed mixture frequently has a comparatively high viscosity, such as mayonnaise or toothpaste, thereby causing some residue of the mixture to adhere to the agitator blades as well as to the inside walls of the mixing tank. It is necessary to thoroughly clean the interior of the mixing tank prior to beginning a subsequent mixing batch in order to maintain mixture purity and uniformity. A tank may be subsequently used to produce a mixture that is different from the previous mixture, therefore making thorough tank cleaning especially necessary. 
         [0004]    Tank cleaning apparatus, such as cleaning machinery sold by the present applicant under the trademark GAMAJET, are commercially available. These tank cleaning machines are lowered into a tank that requires cleaning through an access port subsequent to completing the mixing operation and draining most of the mixture. After draining, a relatively small amount of residue clings to the tank inside wall surface and to the shaft and blades of the agitator. The conventional tank cleaning machines are effective in cleaning residue from the tank inside wall surface, the mixer shaft, and the upwardly facing surfaces of the mixing blades. However, the downwardly facing surfaces of the mixing blades are not in the tank cleaning machine&#39;s spray pattern, and the clinging mixture residue sometimes remains on lower surfaces of the blades. 
         [0005]    Prior designs for apparatus for assembly to a tank for cleaning the interior thereof include: 
         [0006]    U.S. Published Patent Application No. 2011/0088732 to Savard for a Flexible Tank Cleaning Apparatus With Control Linkage. The Savard invention is for installation to a tank below the liquid fill line with the output end of the apparatus extending into the tank. A control linkage is connected to a flexible output end of the tubing for movement between a retracted position and an extended position, the linkage being able to change orientation in order to change the direction of fluid discharge. 
         [0007]    U.S. Published Patent Application No. 2014/0124009 to Jensen is for a Pop-Up Nozzle, Cleaning Device And Method Of Operation. The Jensen patent application discloses a nozzle body to be connected to a tank, with a nozzle being contained within the nozzle body. The nozzle is able to be moved from a retracted position to an extended position. Apertures are exposed for discharging a fluid when the nozzle is in the extended position. 
         [0008]    The present invention described below provides a particularly effective apparatus for cleaning objects within a mixing tank, especially the downwardly facing surfaces of a mixing agitator. 
       SUMMARY 
       [0009]    Disclosed herein is a fluid ejection apparatus adapted for mounting to a mixing tank having a mixing agitator positioned therein. The fluid ejection apparatus is formed with a housing having three sections that are connected to one another for enclosing a rod having a conical closing element at a first end thereof. The first housing section is formed with a conical cavity configured for receiving the closing element in sealing relation. A spring is mounted within the housing to bias the rod and closing element to a closed position. A pressurized fluid is connected to flow into the housing and force the closing element and the s rod into an open position, allowing the fluid to be ejected to clean the mixing agitator. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The present invention is best understood in conjunction with the accompanying schematic drawing figures in which the elements are identified by similar reference numerals and wherein: 
           [0011]      FIG. 1  is an elevation cross sectional view of an industrial mixing tank with a fluid ejection apparatus according to the invention mounted thereto, the fluid ejection apparatus shown enlarged for clarity. 
           [0012]      FIG. 2  is a detailed cross sectional view of the fluid ejection apparatus with a rod and closure element in closed position. 
           [0013]      FIG. 3  is a detailed cross sectional view of the fluid ejection apparatus with the rod and closure element in open position. 
           [0014]      FIG. 4  is a cross sectional view of an upper section of the fluid ejection apparatus as indicated by line  4 - 4  of  FIG. 3 . 
           [0015]      FIG. 5A  is an exploded side elevation view of external portions of the fluid ejection apparatus. 
           [0016]      FIG. 5B  is an exploded side elevation view of internal components of the fluid ejection apparatus. 
           [0017]      FIG. 6  is a detailed cross sectional view of another embodiment of a fluid ejection apparatus with a rod and closure element in closed position. 
           [0018]      FIG. 7  is a detailed cross sectional view of the fluid ejection apparatus of  FIG. 6 , with the rod and closure element approaching an open position. 
           [0019]      FIG. 8  is a cross sectional view of an upper section of the fluid ejection apparatus of  FIG. 7 , as seen along line A 1 -A 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Referring to  FIG. 1 , an industrial mixing tank  10  is illustrated in schematic side elevation cross sectional view. Tank  10  has an access port  12  through an upper wall thereof. In addition, a drive mechanism  18  is mounted to tank  10  with an agitator  14  connected to drive mechanism  18  by means of a shaft  16 . Drive mechanism  18  is capable of causing agitator  14  to rotate, e.g. in the direction indicated by arrow A. Drive mechanism  18  may be an electric, pneumatic, or other type of rotary drive apparatus. Drive mechanism  18  may rotate agitator  14  in either a clockwise or counterclockwise rotational direction. A conventional tank cleaning machine (not shown) as noted above may be inserted into tank  10  through access port  12  for cleaning residue from the inside walls of tank  10  and the upwardly facing surfaces of agitator  14  after the mix batch has been drained. 
         [0021]    Referring further to  FIG. 1 , a fluid ejection apparatus  20  is shown mounted to a lower surface of tank  10 . The tank  10  is provided with a tank flange  22 , and the fluid ejection apparatus  20  is provided with a connector flange  23 . When mounting the fluid ejection apparatus  20  to the tank  10 , the connector flange  23  is brought into aligned contact with the tank flange  22  and the flanges  22 ,  23  are connected to one another, e.g. by a ring clamp (not shown). A fluid inlet  28  is formed into the fluid ejection apparatus  20  in order to conduct a pressurized fluid B, e.g. a cleaning fluid, into the fluid ejection apparatus  20 . Means are provided for attaching a source of pressurized fluid to the fluid inlet  28 , e.g. a connecting flange  29 . Through an internal mechanism to be described below, fluid B is discharged from the fluid ejection apparatus  20  in an upwardly divergent conical spray pattern. It is particularly noted that a central axis X of fluid ejection apparatus  20  is located substantially parallel to, and laterally offset from, an axis Y of the agitator shaft  16 , but still with the fluid ejection apparatus  20  s positioned under the agitator  14 . By this eccentric positioning of the fluid ejection apparatus  20  relative to the agitator shaft  16 , ejected cleaning fluid B is able to impinge all portions of downwardly facing surfaces of the agitator  14 . 
         [0022]    Referring now to  FIG. 2 , the fluid ejection apparatus  20  is illustrated in enlarged cross sectional view as fully assembled in closed position P 1  and before a pressurized fluid is introduced. For reasons of clarity, such mechanical details as liquid retention seals are not shown in the drawings but are assumed as an integral part of the apparatus design. The fluid ejection apparatus  20  has a substantially hollow, central housing section  44 , also referred to as body  44 , with an expanded chamber  46  formed therein. The inlet connection flange  29  is formed for connecting the apparatus  20  to a source of pressurized fluid. The fluid inlet  28  is adapted to conduct a pressurized fluid from a pressurized fluid source into the chamber  46 . An upper housing section  24 , also referred to as upper section  24  or upper cap  24 , is assembled to the body  44  by threads  36  that are effective to contain a pressurized fluid and is able to be opened for periodic maintenance. A plurality of outlet channels  26  extend from the chamber  46  through the upper cap  24  in parallel relation to axis X. A lower housing section  50 , also referred to as lower section  50  or lower cap  50 , is connected to the body  44  by threads  52 , similarly formed to threads  36  described above. The lower cap  50  encases a spring  40  therein. The upper cap  24 , the body  44 , and the lower cap  50  provide first (upper), second (central), and third (lower) sections  24 ,  44 ,  50  of a housing for the fluid ejection apparatus  20 . 
         [0023]    Referring further to  FIG. 2 , a rod  34  is slidingly assembled within the body  44  in parallel relation along axis X. A closure element  30  is formed at a first end  34   a  of the rod  34 . The closure element  30  is substantially conical in form. The closure element  30  may be formed integral with the rod  34  or as a separate component and assembled to the rod  34  by any appropriate fastening method. When the fluid ejection apparatus  20  is in the closed position P 1  the closure element  30  engages an inner wall of the upper cap  24  in order to prevent the mixing batch in tank  10  (see  FIG. 1 ) from seeping into the chamber  46 . A seal  32 , e.g. an “O” ring, is provided around a central area of the closure element  30 . A lower end  34   b  of the rod  34  extends through the chamber  46  and through the spring  40 . A base member  38 , which may be embodied as base plate  38 , is assembled to the lower end  34   b  of the rod  34  by a fastener  42 , e.g. a screw, or by some other suitable method. The spring  40  is a compression spring, such as a constant modulus compression spring, shown here in expanded condition with the rod  34  and the closure element  30  in the closed position P 1 . 
         [0024]    Referring now to  FIG. 3 , the fluid ejection apparatus  20  is illustrated in an open position P 2  after pressurized fluid B has been introduced thereto. Pressurized fluid B is conducted through the inlet  28  to enter the chamber  46  within the body  44  to flow in parallel to axis X. Whereas the rod  34  passes snugly through a lower portion of the body  44 , with sealing elements included as appropriate, the flow and pressure of pressurized fluid B are directed upwardly through the outlet channels  26  to force the closure element  30  and the rod  34  upwardly. As the closure element  30  is substantially conical in shape, upward movement of the closure element  30  creates a conical outlet  25  through which pressurized fluid B is discharged in an upwardly divergent conical flow pattern. Other flow patterns may be obtained by using other shapes for the closure element and the conical outlet. Due to the closure element  30  and the rod  34  being moved upwardly (as illustrated), the rod  34  and the base plate  38  force the spring  40  to be compressed. The constant modulus spring  40  may be calibrated to compress when the pressure of pressurized fluid B reaches a level of approximately twice the standard atmospheric pressure. The standard atmospheric pressure is about 101 kilopascal. Whereas small amounts of pressurized fluid B may seep downward along rod  34  and around any seals provided, one or more drain holes  56 ,  58  are provided through the lower cap  50  in order to minimize a possible back pressure within the lower cap  50 . As will be understood, without drain holes  56 ,  58  fluid that might settle in the lower cap  50  would prevent the rod  34  from fully returning to the closed position P 1  depicted in  FIG. 2  and therefore prevent the closure element  30  and the seal  32  from sealing against the wall of the outlet  25 . Lack of a proper seal between the s closure element  30 , the seal  32  and the outlet  25  would potentially allow a liquid being mixed in tank  10  (see  FIG. 1 ) to enter fluid the ejection apparatus  20  and disturb proper operation thereof. 
         [0025]    Referring now to  FIG. 4 , a cross sectional view of the upper cap  24  as taken in the direction indicated by line  4 - 4  of  FIG. 3  is illustrated. External threads  36  are formed on a lower part of the upper cap  24  to engage mating threads within the body  44  (see  FIGS. 2, 3 . A central hole  27  is formed in the upper cap  24  to slidingly receive the rod  34  (see  FIGS. 2, 3 . A series of outlet channels  26  are formed in a circular array around the central hole  27 . In the exemplified embodiment of the apparatus, the outlet channels  26  are formed arcuately. Whereas four outlet channels  26  are illustrated, other numbers of outlet channels  26  may be employed. 
         [0026]    Referring now to  FIGS. 5A and 5B , the fluid ejection apparatus  20  is shown in exploded elevation view. As best seen in  FIG. 5B , closure element  30  is formed as a compound cone with a lower portion  30   a  formed at an angle J to axis X and an upper portion  30   b  formed at another angle K to axis X. The angle J for the lower portion  30   a  is larger than the angle K for the upper portion  30   b.  The seal  32  is placed in a receiving circumferential groove between the lower portion  30   a  and the upper portion  30   b.  The angle K for the upper portion  30   b  is smaller than the angle J for the lower portion  30   a.    
         [0027]    When assembling the fluid ejection apparatus  20  the upper cap  24  is first threadingly mounted to the upper end of body  44 . The lower end  34   b  of rod  34  is inserted through the upper cap  24  to pass longitudinally through the body  44 . The spring  40  is placed over the lower end  34   b  of the rod  34  and the spring  40  is positioned into the lower end of the body  44 . Next the base plate  38  is placed against the lower end  34   b  and affixed thereto by the fastener  42  or other means of attachment. At this stage of assembly, the closure element  30  is held in, or pulled against, the outlet  25  by the force of the spring  40  against the base plate  38 . Finally, the lower cap  50  is threadingly mounted to the lower end of the body  44  to seal the fluid ejection apparatus  20 . As noted above, sealing elements, e.g. “O” rings, are employed within the fluid ejection apparatus  20  as appropriate. Fluid ejection apparatus  20  is now in condition to be mounted by means of the connector flange  23  to a mixing tank (see  FIG. 1 ) with the inlet  28  being connected to a source of pressurized fluid, e.g. cleaning fluid. 
         [0028]    Referring to  FIG. 6 , another embodiment of the fluid ejection apparatus  20 * is illustrated. In this embodiment all features of the fluid ejection apparatus  20 * are the same as for the fluid ejection apparatus  20  of  FIG. 2 , apart from the closure element  30 * and the upper housing section  24 *, and operates in the same way. Features of the fluid ejection apparatus  20 * of  FIG. 6  that are the same as features of the fluid ejection apparatus  20  of  FIG. 2  share the same reference numerals. 
         [0029]    Specifically, the closure element  30 * comprises a through hole  301  for allowing fluid to pass through the closure element  30 * when the rod  34  is in the open position. In the illustrated embodiment there is a second, similar through hole in the closure element  30 *. The second through hole in the closure element that is arranged opposite the first through hole  301 , as seen relative the central axis X. The upper housing section  24 * has a first plug  241  for the first through hole  301  and a second plug for the second though hole. The first plug  241  seals the first through hole  301  when the rod  34  is in the closed position, while the second plug seals the second though hole. When the rod  34  is in the closed position, the plugs  241  extend into the holes  301  and block the holes. When the valve rod  34  moves towards the open position, then the closure element  30 * is lifted as shown in  FIG. 7 , which the result the through holes are lifted off from the plugs. When the valve rod  34  is fully lifted then the through holes  301  are fully lifted off from the plugs  241  and their bottoms are exposed such that pressurized fluid B may flow into the through holes  301 , through them and out from them such that small jet beam are formed. These jet beams have a direction that is parallel to central axis X. 
         [0030]    Referring to  FIG. 8 , a cross sectional view of the upper housing section  24 * as seen in the direction indicated by line A 1 -A 1  of  FIG. 7  is illustrated. The central hole  27  is formed in the upper housing section  24 * to slidingly receive the rod  34 . A series of outlet channels  26  are formed around the central hole  27 . The plugs  241  are arranged on a respective side of the central hole  27 , between the outlet channels  26 . When the valve rod  34  is in the fully open position, the pressurized fluid B flows from the chamber  46 , through the channels  26 , into the through holes  301  respectively around the closure element  30 *, and out from the through holes  301  as straight beams respectively out from around the closure element  30 * in form of a cone-shaped beam. 
         [0031]    It is possible to arrange another number of through holes in the closure element, such as one, three or more holes. Each through hole is plugged with a corresponding plug when the rod  34  is in the closed position. 
         [0032]    While the description above discloses a preferred embodiment of the fluid ejection apparatus, it is contemplated that numerous variations and modifications of the invention are possible and are considered to be within the scope of the claims that follow. Moreover, any type of tank agitator may be cleaned by the described fluid ejection apparatus  20 , as long as the fluid ejection apparatus  20  is arranged so that the fluid impinges, either directly or indirectly, on the tank agitator.