Abstract:
An apparatus for attachment to a commercially available cleaning wand for maneuvering the wand inside a storage tank. Two arms each have an end pivotally connected to a handle and another end pivotally connected to the wand to form a four bar linkage. A gimbal arrangement is supported above a base, which is placed over an opening in the tank, and one of the arms is coupled to the gimbal arrangement to allow movement about three mutually perpendicular axes for directing the wand to various orientations within the tank.

Description:
STATEMENT OF GOVERNMENT INTEREST 
     The invention described herein may be manufactured and used by or for the Government of the United States of America for government purposes without the payment of any royalties therefor. 
     BACKGROUND OF THE INVENTION 
     Various storage tanks, including rail car tanks and other vessels require periodic inspection and internal cleaning to remove fluid or debris built up on the interior tank wall. For example, the tank is cleaned through a manway, or opening, with a lancing, or cleaning wand which is supplied with high-pressure fluid. To clean or inspect the interior an operator generally holds the inspection equipment or cleaning wand through the opening while laying on a personnel platform. If such a platform is not part of the tank structure, a portable staging platform is erected for this purpose. 
     This method of cleaning the tank is cumbersome and uncomfortable for the operator. Further, it is difficult for the operator to hold and direct the cleaning wand while in the prone position. The present invention eases the cleaning operation, allowing it to be done with less effort and in a shorter period of time. Further, for inspection purposes, the present invention allows for easy, controlled inspection of the tank interior. 
     SUMMARY OF THE INVENTION 
     The present invention includes an apparatus for maneuvering a device such as a cleaning wand supplied with high-pressure fluid for cleaning the interior of a storage tank, the tank having an opening through which the wand is inserted. The apparatus includes a base with an outer gimbal ring disposed above the base and a plurality of legs connecting the outer gimbal ring with the base. First and second shafts connect an inner gimbal ring with the outer gimbal ring in a manner to permit oscillation of the inner gimbal ring about a first axis. 
     A sleeve is positioned within the inner gimbal ring with third and fourth shafts connecting the sleeve with the inner gimbal ring in a manner to permit oscillation of the sleeve about a second axis perpendicular to the first axis. First and second pivotal connectors are positioned at spaced apart locations on a handle member with a first arm having a first end being connected to the first pivotal connector and passing through the sleeve. A second arm having a first end is connected to the second pivotal connector. A swivel bushing surrounds and is secured to the first arm and is positioned on top of the sleeve to permit rotation of the first arm about a vertical axis. 
     Third and fourth pivotal connectors are positioned at respective second ends of the first and second arms for connection to the device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be better understood, and further objects, features and advantages thereof will become more apparent from the following description of the preferred embodiment, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a side view, partially in section, of one embodiment of the present invention. 
         FIG. 2  is a view along the line  2 — 2  of  FIG. 1 . 
         FIG. 2A  illustrates a gimbal ring of  FIGS. 1 and 2  in more detail. 
         FIG. 2B  illustrates an end member in more detail. 
         FIGS. 3A and 3B  are views of the apparatus in two different orientations. 
         FIG. 4  is a perspective view of the apparatus over an opening in a tank. 
         FIG. 5  is a plan view of a pivotal connector utilized herein. 
         FIG. 6  is a view along the line  6 — 6  of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the drawings, which are not necessarily to scale, like or corresponding parts are denoted by like or corresponding reference numerals. Although the apparatus is applicable to various devices including inspection cameras and other viewing gear, it will be described, by way of example, with respect to cleaning equipment. 
     Referring now to  FIGS. 1 and 2 , the cleaning apparatus  10  includes a base member  12  and an outer gimbal ring  14  supported above the base  12  by a plurality of legs  16 . An inner gimbal ring  18  is connected to the outer gimbal ring  14  by respective first and second shafts  19  and  20  in a manner to permit oscillation of the inner gimbal ring  18  about a first axis X. 
     More particularly, and in a preferred embodiment, each shaft  19  and  20  includes a respective end member  22  and  23  which reside, and are rotatable in, respective diametrically opposed notches  26  and  27  of the outer gimbal ring  14 , best illustrated in  FIG. 2A . A typical end member  22  is illustrated in  FIG. 2B . The end member  22  includes a central cylindrical portion  30  straddled by opposed flanges  31  and  32 . Central cylindrical portion  30  may oscillate in the notch  26  about axis X, while flanges  31  and  32  limit axial movement of shaft  19 . This same structure and operation also describes end member  23  residing in notch  27 . The shafts  19  and  20  may be metal pipes and the end members  22  and  23  may be of a hard durable plastic material. 
     Referring once again to  FIGS. 1 and 2 , the apparatus includes a sleeve  40  positioned within the inner gimbal ring  18  and connected to the inner gimbal ring  18  by means of respective third and fourth shafts  42  and  43  in a manner to permit oscillation of the sleeve  40  about a second axis Y, perpendicular to first axis X. The third and fourth shafts  42  and  43  may be constituted by shoulder bolts passing through respective apertures in inner gimbal ring  18  and threaded to sleeve  40 . 
     The apparatus utilizes a linkage comprised of a handle  46  having first and second pivotal connectors  47  and  48  positioned at spaced apart locations on the handle  46 . In the embodiment illustrated, the first pivotal connector  47  is located at an end of the handle  46 . Depending from the first pivotal connector  47  is a first arm  50  which passes through the sleeve  40  as well as a swivel bushing  52  secured to arm  50  by means of, for example, a thumbscrew  54 . The swivel bushing  52  rests on, and is rotatable relative to, the top of the sleeve  40 , thus permitting rotation of the arm  50  about a vertical axis Z. 
     A third component of the linkage is comprised of a second arm  56  which is connected to the second pivotal connector  48  and remains parallel to the first arm  50  during operation. Positioned at respective second ends of arms  50  and  56  are third and fourth pivotal connectors  60  and  61  for connection to a commercially available lancing, or cleaning wand  64 , which is supplied with high pressure fluid via flexible hose  66 . When attached, the cleaning wand  64  completes a four bar linkage, along with handle  46  and arms  50  and  56 , for leverage and motion maneuverability of the wand. The handle  46  and first and second arms  50  and  56  are preferably hollow tubes. 
     For example,  FIGS. 3A and 3B  illustrate the apparatus placed on a support platform  70  over a manway, or opening  72 , of a storage tank  74 , having an interior  76 . With the four bar linkage, when the handle  46  is raised, the cleaning wand  64  is directed to a downward position. Conversely, and as indicated in  FIG. 3B , when the handle  46  is depressed, the cleaning wand  64  is directed to an upward position. Handle  46  is also utilized to rotate the linkage around approximately 180°, and to this end reference is made to  FIG. 4 . 
       FIG. 4  is a view of the apparatus on the support platform  70 , and illustrates the cleaning wand  64  in the interior  76  of the storage tank  74 . By manipulating the handle  46  (partially shown in  FIG. 4 ), shafts  19  and  20  may be oscillated in the direction of arrow  78 , about the X axis. Further, sleeve  40  may be oscillated in the direction of arrow  79 , about the Y axis, and in addition, arm  50  may be rotated for limited movement of approximately 180° about the Z axis, as indicated by arrow  80 . That is, arm  50  may be rotated between the limits wherein arm  56  encounters shaft  19  at one extreme and shaft  20  at the other extreme. Therefore, the arrangement provides for the cleaning coverage of approximately one half of the tank interior walls. After a cleaning operation with the apparatus placed as illustrated in  FIG. 4 , the base  12  may be physically rotated, one or more times, such that the remaining coverage may be accomplished. 
     Various pivotal connector designs may be used herein and  FIG. 5  illustrates one such connector  47  for arm  50 . Pivotal connector  47  is a clevis having a shank  84  inserted within handle  46  and secured to it by a pin  85 . The U-shaped end  86  of the clevis accommodates the first arm  50  which is free to pivot about a pin such as a shoulder bolt  87 . 
       FIG. 6  illustrates one type of pivotal connector for second arm  56 . Connector  48  includes an upper portion  90  which is clamped around the handle  46  and secured in place by means of bolt  91 . A U-shaped lower portion  92  accommodates the arm  56  which is free to pivot about a pin such as a shoulder bolt  93 . Pivotal connectors  60  and  61  for the cleaning wand may be of a design such as illustrated in  FIG. 6 , or may be of any design which allows for the pivotal movement of the linkage system. 
     It will be readily seen by one of ordinary skill in the art that the present invention fulfills all of the objects set forth herein. After reading the foregoing specification, one of ordinary skill in the art will be able to effect various changes, substitutions of equivalents and various other aspects of the present invention as broadly disclosed herein. It is therefore intended that the protection granted hereon be limited only by the definition contained in the appended claims and equivalents. Having thus shown and described what is at present considered to be the preferred embodiment of the present invention, it should be noted that the same has been made by way of illustration and not limitation. Accordingly, all modifications, alterations and changes coming within the spirit and scope of the present invention are herein meant to be included.