Apparatus for washing tanks
United States Patent 2078568

This invention has to do with devices for washing the interior of ships tanks and the like. In my copending application, Serial No. 678,137, I have disclosed a form of tank washer for dislodging oil and/or similar encrustations from the interior walls and bottoms of tanks on shipboard used...

George, Leonard B.
Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
International Classes:
B05B3/04; B05B3/06
View Patent Images:


This invention has to do with devices for washing the interior of ships tanks and the like. In my copending application, Serial No. 678,137, I have disclosed a form of tank washer for dislodging oil and/or similar encrustations from the interior walls and bottoms of tanks on shipboard used for the transporting of oils. This prior disclosure shows a tank washer comprising a selfdriven spray head capable of forming jets of cleaning fluid and continuously rotating them through a constantly changing path. This spray head is supplied with jetting liquid by a hose which additionally acts as the sole support of the jetting device, allowing it to be lowered to a variable depth within the tank being washed. This invention is directed to improvements in the general form of device and method of cleaning above described.

I have found that when washing heavier oils I may get a more efficient cleansing action and accomplish an equal cleaning with a lesser amount of jetted liquid if it is possible to move the jets by steps, rather than continuously. To accomplish this, I allow the jet to play continuously upon a certain point for an instant, without substantial movement, and then advance it along its customary path to a second point. I have further found in the use of this device that it is quite possible after a little experience, to predict the length of time it will take to complete, the washing of a tank, and by so predicting, predetermine the length of time the device should operate and arrange to cease its operation at the expiration of such period.

It has been an object of this invention to provide a device which will wash the interior of a tank with a jet advancing stepwise through a continuously changing path. A further object has been the provision of means whereby that advance may be made optionally either stepwise or continuous. A further object has been the incorporation of means whereby the velocity of travel of the cleaning jet along its path can be varied. Among the objects have been the provision of means whereby the jetting device may be self-stopping after rotation for a predetermined period, refinements in design whereby greater compactness and portability might be achieved, and such other objects and advantages as may appear within the following specification.

All of these objects and advantages I have attained by the novel arrangement of apparatus parts, and for an understanding of these, reference is made to the drawings attached to and forming a part of this specification.

In the drawings: Figure 1 shows a section of the spray device, taken through the centerline.

Figure 2 shows a view, in section, taken at an angle of 900 to the view of Figure 1. Figure 3 shows a partial sectional view of the apparatus.

Figure 4 shows a detail of an alternate tooth construction.

Figure 5 shows an elevation of the apparatus, and Figure 6 shows a plan view.

Throughout all of these views, like numbers are used on like parts.

In Figure 1, 6 represents the fixed body portion of the spray head, having central water passage 7, equipped with a threaded end 8 by which it may be attached to a hose, and terminating in a threaded neck 9. This body is formed with a shoulder 10, which is shaped to permit the application of a wrench, and is extended to form flange I , on the circumference of which is a toothed gear 12, and from which is extended an annular sleeve 13, concentric with passage 7. The mid-portion of body 6 is formed into a cone, 14, through which there are a plurality of passages 15, so that liquid from passage 7 may pass to the interior of the surrounding casting. A separately formed annular body 16 is placed around sleeve 13, resting against flange I ,. and secured thereto by one or more bolts 17. A portion of the circumferential face of this ring 16 is cut to form a worm rack gear 18, and the remainder of the face, 19, is faced off at a diameter approximately equal to the diameter of spur gear 12 at the root of the teeth. On this faced portion 19 there are placed one or more teeth, 20, so that the circumferential face of ring 16 presents not only worm rack 18, but also a spur gear 20, of the same pitch diameter as spur gear 12, but with all except a few teeth missing. The cooperating faces of IS and of 13 and 1 are so machined that 16 may rotate upon 1 as a bearing, if desired, for a purpose to be explained hereinafter.

Surrounding body 6 and free to rotate about body 6 using the machined exterior of that body as a bearing, is a second casting 21. This casting has an upwardly extending neck 22, extending along 6 within sleeve 13, and is equipped with packing gland 23 and gland nut 24, whereby the joint between 21 and 6 may be sealed. A flange 25 is attached to 21 and machined to form the remainder of a housing for ring 16. Body 21 has an opening 26, through which neck 7 of body 6 passes, and is secured upon body 6 by nut 27 and locknut 28 run upon bolt 7, the friction and thrust being taken by several washers 29 formed of suitable material. Body 21 is formed to provide a threaded collar 30, and a cover 31, secured thereto, protects the assembly at this point and provides a reservoir for lubricant. Body 21 is provided with interior liquid passage 32 and on one side has extension 33 and interior thereto liquid passage 34. This passage conveys liquid to a set of rotating nozzles, constructed as follows: two nozzles formed to convert a major portion of liquid pressure head into velocity, designated by 35 and 35', are formed as part of a body, the base of which is a circular plate 36, upon which is formed bevel gear 37. A sleeve 38 is screwed into this base, and is so machined that it can extend within and be capable of free rotation within passage 34 in body 21. A portion of the exterior of this sleeve 38 is formed to provide ball-race 39. Another sleeve, 40 is threaded upon the exterior of 33, this sleeve providing ball race 41, which, in cooperation with balls 42 and race 39, forms a ball-bearing joint whereby the nozzles may rotate with respect to body 21. A packing recess 43 is provided to protect the bearing against cleaning fluid. The diameter of the gear 37 is such that when the device is assembled, it may mesh with gear 12 on body 6. The face of the teeth in gear 37 is equal in width to the face of the teeth in gear 12 plus the face of the teeth in mutilated gear 19 on ring 16. When ring 16 is rigidly secured to flange II by bolts 17, no one of the one or more-teeth of mutilated gear 19 is in contact with gear 37. Then when body 21, driven by a mechanism later described, rotates with respect to body 6, the engagement of gears 12 and 37 produces a rotation of the nozzles 35 with respect to body 21.

To describe the mechanism by which relative rotation of bodies 21 and 6 is effected, Figures 2 and 3 should be read in conjunction. Within body 21 a second passage 44, communicating with passage 32, is led off at a direction at right angles to passage 34. This passage communicates with an interior cavity 45 in body 46, which body 46 is secured to the side of body 21 upon a machined seat prepared for it, and retained by screws 47.

A strainer 48 is placed within cavity 45. Body 46 is formed in the shape of a yoke, with two upstanding lugs, 50 and 51. (Figure 3.) Leading from cavity 45, a liquid passage 49 goes to lug 51.

Journaled within these lugs 50 and 51, is a tube 52, which rests upon a combined thrust bearing and packing at 53. Surrounding tube 52, in the space between lugs 50 and 51, and keyed to the tube, is a worm, 54. Secured to the threaded end of tube 52, where it extends beyond lug 50 is a T casting 55, terminating in two reaction nozzles 56 and 56'. Liquid diverted through passages 44, 45 and 49, then through tube 52 and nozzle 56 will cause rotation of these nozzles, and that rotation, communicated through tube 52 and worm 54 to worm rack 18 on ring 6S, causes relative rotation of ring I1 and body 21. When ring 16 is secured to body 6 by bolts 1T, relative rotation of body 21 about body 6 occurs.

To vary the amount of fluid delivered to reaction jets 56 and consequently vary the rate of rotation, I have provided threaded plug 57, mounted in lug 5 . This plug can be advanced to 7( close the passage 49 to any degree, and so regulate the speed.

To explain how to accomplish intermittent movement of the device, we may return to Figure 1. Bolts 17 are removed, and now ring 16 rotates with respect to both 6 and 21, The engagement of gear 31 with gear 12 not only holds nozzles 35 in fixed position with respect to body 6, but also holds body 21 in a fixed position. One of the teeth in mutilated gear 19, (on ring 16), now engages gear 37, causing the nozzles to rotate with respect to body 21. This can only be accomplished by permitting a rotation between 21 and 6 as well, and the mechanism thus accomplishes a step-wise progress on its course.

In the place of the mutilated gear 19, I sometimes find it preferable to finish the face of ring 16 without teeth, and insert in it one or more spring teeth, as shown in detail in Figure 4, to serve the purpose of mutilated gear 19. In Figure 4 a detail of this spring tooth is shown in plan. 66 indicates a hole of the proper dimensions located in ring 16, 67 indicates the retractable tooth, 68 is the spring by which it is forced into an engaging position, and the tooth is retained by peg 69, in slot 70. To accomplish stopping the device after operating a predetermined length of time, recourse is had to a mechanism shown in Figure 3. Near the bottom of body 46 is formed a slot, 58, the cross section of which is clearly shown in Figure 2. This slot terminates at either end in a circular hole. Through hole 59, at the right in the view, there is inserted a threaded shaft 60, which carries on its outer end a star wheel 61 and on its inner end a pin 62. Pin 62 is supported in a 3S~ bearing formed in the end of screw 63 which is inserted at the other end of the slot. A nut 64, shaped to fit snugly within slot 58 and to be thereby prevented from turning, moves upon the threads of shaft 60. A peg 65 (Fig. 2) inserted in the under side of circular plate 36 serves to actuate the star wheel 61. A mark on nut 64 cooperates with a scale marked along the side of slot 58 to show what degree of advancement of nut 64 along shaft 60 corresponds to a certain number of rotations of nozzles 35. Then, nut 64 being set, and the washer in operation, each movement of the star wheel 61 brings nut 64 nearer its stop at the right hand end of slot 58.

When this point is reached the star wheel engages pin 65, and stops the rotation of the entire device.

I claim: 1. In a self rotating sprayhead for use in washing the interior of ships tanks and the like, a fixed body comprising a threaded portion and a spindle terminating in a second threaded portion, a flange upon said fixed body terminating in a toothed gear, a central liquid passage in said liquid passage and ports whereby liquid may pass from said central passage to a point without said spindle; a movable body formed to envelop said spindle and rotate thereabout upon their common centerline, retaining means upon the second threaded portion of said spindle acting to hold the movable body in engagement with the fixed body, a central liquid space within the movable body into which liquid from the spindle may be discharged, an arm upon one side of said movable body and a liquid passage therein communicating with the central liquid space, a pair of nozzles rotatively mounted upon said arm at the extremity thereof, communicating with the liquid passage therein, and arranged to form jets of the liquid passing therethrough, directing them in a plane perpendicular to the centerline of said arm and said liquid passage, a bevel gear mounted upon said nozzles and arranged to rotate therewith and to engage the toothed periphery of the flange upon the fixed body in such manner that relative rotation of the movable body about the fixed body will cause secondary rotation of the nozzles with respect to the moving body; a second liquid diversion passage within the movable body communicating with the central liquid space thereof, a yoke formed projection upon said movable body, a tube within said yoke, a worm mounted upon said tube between the arms of said yoke, passages whereby the second diverted stream of 0 liquid may pass to one end of said tube and then axially therethrough, reaction nozzles rigidly fixed to the outboard end of said tube whereby the jetting of said second diverted liquid will give rise to rotary motion to be transmitted from said reaction nozzles through said tube to said worm; a ring formed body affixed to the flange of the first mentioned fixed body, and upon the periphery of the ring formed body a worm gear, cooperating with said worm, whereby the motion of the reaction jets may act to cause rotation of the movable body about the fixed body.

2. In a spray head for use in washing the interior of tanks, a fixed body and a movable body 25 adapted to rotate about the common center line, communicating passages for liquid within each body, a fixed gear on the fixed body and a second gear thereon arranged for fixed or movable relation to said fixed body, said second gear having two sets of gear teeth thereon of which one set is mutilated, liquid reaction jets on the movable body for driving a gear meshed with said second gear through one set of teeth, jet forming nozzles, mounted upon said movable body, supplied with 5 liquid therefrom and arranged to rotate with respect to said movable body about a center line angularly disposed to that of said movable body, a gear on said nozzles meshing with the mutilated set of teeth on said second gear and with the fixed gear, whereby rotation of the nozzles about the center line angularly disposed to that of the movable body, and rotation of the movable body and the nozzles about the center line of the fixed body may be effected simultaneously.

3. An apparatus according to claim 2 in which the set of gear teeth on the second gear meshing with the gear on the nozzles is in the form of a mutilated gear having retractable teeth.

4. In a spray head according to claim 2 a means for establishing a predetermined speed of rotation for said nozzles about the horizontal and vertical axes thereof consisting of an adjustable plug in the passage communicating with the reaction jets whereby the quantity of liquid escaping therefrom may be regulated so as to govern the speed of rotation.

5. In a spray head according to claim 2 a means for automatically interrupting the rotation of said nozzles about the vertical and horizontal axes thereof at a predetermined point consisting of a star wheel mounted in a space between the movable body and the nozzles supported by a threaded shaft passing through a narrow passageway formed on said body, a slide member mounted on said shaft in threaded engagement therewith so as to move through the passageway by the rotation of the wheel and shaft to binding engagement with one end of the passageway, a stud carried by the nozzles and adapted to engage the star wheel to cause rotation thereof until said slide member binds and interrupts movement of the entire assembly. 6. A spray head according to claim 2 in which the second gear is an annular member disposed in a raceway adjacent the upper end of the head, said raceway being formed by means of cooperating flanged portions on the fixed and movable bodies, said annular member having threaded openings in its upper face adapted for engagement with bolts which may be threaded through corresponding openings in the flanged portion of the fixed body.