Hydraulic tank cleaning apparatus

APPLICATIONS

This application is a continuation-in-part of application Ser. No. 619,858, filed Mar. 1, 1967, now abandoned.

BACKGROUND OF THE INVENTION

Tank cleaning machines have heretofore been provided and have utilized a source of liquid for operating the machine. Conventionally, this source of liquid drives a propeller mounted on a propeller shaft which passes through a gear box. It is found that the seals and thrust bearings provided for the propeller shaft are subject to excessive wear. Therefore, frequently there is leakage past these seals and bearings which necessitates their replacement. In addition, such machines have been relatively bulky, making it impossible to use them with tanks having small openings therein. There is, therefore, a need for a new and improved hydraulic tank cleaning apparatus.

SUMMARY OF THE INVENTION AND OBJECTS

The hydraulic tank cleaning apparatus of the present invention consists of a stem or stationary housing which is connected to a source of fluid, with the stem or stationary housing having openings therein to permit the passage of fluid through the stem or stationary housing. A rotatable housing is rotatably mounted on the stem or stationary housing and is provided with a cylindrical extension which has a flow passage therein which is movable into communication with the openings in the stem. A nozzle housing is rotatably mounted on the stem and has a passage adapted to be moved into communication with openings in the cylindrical extension. Nozzles are carried by the nozzle housing and receive fluid from the nozzle housing. Means is provided for causing rotation of the rotatable housing on the stem and for causing rotation of the nozzle housing on the cylindrical extension or rotatable housing and includes a gear train. A propeller is provided for driving the gear train which is mounted away from the stem and out of the main flow of the cleaning fluid through the cleaning apparatus. Nozzle means is provided for supplying a portion of the fluid to drive the propeller. In another embodiment, the propeller is mounted in the main stream flow and drives a planetary gear train having helical teeth.

In general, it is an object of the present invention to provide a hydraulic tank cleaning apparatus which is relatively small and compact.

Another object of the invention is to provide a tank cleaning apparatus of the above character in which the gear box utilized in the apparatus is sealed and is separated from the main stream with none of the moving parts disposed in the main stream.

Another object of the invention is to provide tank 5 cleaning apparatus of the above character in which the impeller is positioned out of the main stream of the cleaning fluid and is driven by a jet stream of the cleaning fluid so that an open passage is provided for the flow of the main stream of the cleaning fluid.

Another object of the invention is to provide a tank cleaning apparatus of the above character in which various ranges of speed and power can be obtained.

Additional objects and features of the invention will appear from the following description in which the pre15 ferred embodiment is set forth in detail in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1 is a cross-sectional view of a tank clean20 ing apparatus incorporating the present invention.

FIGURE 2 is a cross-sectional view taken along the line 2—2 of FIGURE 1.

FIGURE 3 is a cross-sectional view taken along the line 3—3 of FIGURE 1.

FIGURE 4 is a cross-sectional view of another embodiment of a tank cleaning apparatus incorporating the present invention.

As shown in FIGURES 1-3 of the drawings, the tank cleaning apparatus consists of a stationary, substantially cylindrical stem or stationary housing 10 which has an adapter 11 threaded thereon. The upper end of the adapter 11 is provided with threads which can be external or internal and is adapted to be connected to the end of the hose or pipe which is carrying the cleaning fluid which is ⁰ to be utilized by the apparatus. The adapter 11 is provided with an inlet in communication with a flow passage 13 in the stem 10. The stem or stationary housing 10 is provided with four equally spaced vertically extending ₄₀ openings 14 provided in the side wall of the stem 10 'and 'incommunication with the passage 13.

A rotatable housing 16 is carried by the stem or stationary housing 10 and is rotatably mounted on the stem 10 by upper and lower annular bushings 17 which are 45 L-shaped in cross-section and each of which is provided with a lug 17α. The lug 17α of the upper bushing is disposed in a recess in the adapter 11 to prevent the bushing 17 from turning on the stem or stationary housing 10. The lug 17α of the lower bushing 17 is disposed in a 50 recess in a member 19 which is affixed to the lower portion of the stem by cap screws 21. If desired, the stem 10 and the member 19 can be formed in one piece. Sealing means is provided for forming a fluid-tight seal between the stem or stationary housing 10 and the rotatable hous55 ing 16 and consists of O-rings 22 which are held in place by rings 23 which serve as retainers as well as bearing liners. An O-ring 24 disposed in a recess 25 forms a seal between the member 19 and the stem 10.

The rotatable housing 16 is provided with a cylindrical 60 extension 26 which has a flow passage 27 therein which is of such a size that it is always in communication with one of the openings 14 provided in the stem or stationary housing 10. The passage 27 is in communication with four equally spaced openings 28 provided in the cylindrical extension 26.

A rotatable nozzle housing 31 is rotatably mounted upon the cylindrical extension 26 of the rotatable housing 16 by inner and outer bushings 32 which are L-shaped in cross-section. Each is provided with an integral lug 32α. The lug 32α of the inner bushing 32 extends into a recess in the housing 16. The lug 32α on the outer bushing 32

3,464,632 ³ is disposed in a recess in a plate 35 secured to the outer extremity of the extension 26 by cap secrews 36. Sealing means is provided for establishing fluid-tight seals between the cylindrical extension 26 and the nozzle housing 31 and consists of O-rings 33 held in place by rings 34 which also serve as bearing liners. The lugs provided on the bushings 17 and 32 prevent rotation of the bushings and, therefore, minimize wear on the housing. The lugs also make it possible to provide relatively loose bushings so that expansion of the stem or stationary housing will not cause cracking of the bushing when dissimilar materials are used.

Two nozzles 39 are threaded into the nozzle housing 31 and are provided with flow passages 41 which are in communication with passages 42 provided in the housing 31. The passages 42 are adapted to be placed in communication with the openings 28 provided in the extension 26 as the housing 31 rotates.

Means is provided for causing rotation of the nozzle housing 31 with respect to the cylindrical extension 26 and also for causing rotation of the rotatable housing 16 with respect to the stem 10 and consists of a propeller 46 which is secured to a shaft 47 by a pin 48. The shaft 47 is rotatably mounted in a ball bearing assembly 49 carried by a base plate 51. The upper end of the shaft 47 is mounted in a sleeve bearing 52 mounted in a recess 53 provided in the lower portion of the stem or stationary housing 10. The propeller 46 is covered by a protective shroud 56 which, together with the base plate 51, is secured to the rotatable housing 16 by cap screws 57. Suitable means is provided for forming a fluid-tight seal between the base plate 51 and the rotatable housing 16 and consists of an O-ring 58 carried within a recess 59. Sealing means in the form of an O-ring 61 carried in a recess 62 establishes a seal between the base plate 51 and the shaft 47.

A drive pinion 64 is mounted upon the shaft 47 and drives a planetary gear 66. The planetary gear 66 is rotatably mounted upon a bushing 67 which is mounted upon a shaft 68. The shaft 68 is carried by a planetary gear carrier 69 and is retained therein by a retaining ring 71. As can be seen, the bushing 67 is disposed within the carrier 69 to prevent axial movement on the shaft 68. The planetary gear carrier 69 is rotatably mounted upon the shaft 47 by a pair of bearings 72 mounted on the shaft 47 and mounted in the carrier 69. The planetary gear 66 engages an internal ring gear 73 formed integral with the member 19 and a separate loose differential internal ring gear 74. The ring gear 73 is provided with one more tooth than ring gear 74 to give the conventional speed reduction. On each revolution of the planetary gear 66, the internal ring gear 74 is advanced one tooth. Additional teeth may be provided if desired.

Means is provided for forming a friction drive connection between the loose differential gear 74 and the base plate 51 and consists of a split ring 77 disposed in an annular, downwardly facing recess 78 in the differential ring gear 74. The ring 77 is formed of a suitable material such as stainless steel and is formed so that at least a portion and preferably substantially its entire outer circumferential surface engages the outer wall forming the recess 78 whereby there is frictional contact between the same extending over substantially the entire surface of the ring. A pin 79 is mounted in the base plate 51 and extends into the space 81 provided between the ends of the ring 77 as shown particularly in FIGURE 2. As the ring gear 74 is advanced, the housing 16 is driven through the friction ring 77 to the pin 79 and the base plate 51. In place of the pin 79, a lug can be formed integral with the base plate.

It should be appreciated that the positions of the ring 77 and the pin 79 can be interchanged. Thus, the ring 77 could be mounted in a recess in the base plate 51 and the pin could be mounted in the differential gear 74.

Means is provided for establishing a seal between the member 19 and the rotatable housing 16 and consists of an O-ring 82 carried within a recess 83 provided in the member 19.

The member 19 is also provided with bevel gear 84 which is formed integral therewith. The bevel gear 84 engages a bevel gear 86. Bevel gear 86 has one more tooth than bevel gear 84 so that in one revolution of the housing 16, the bevel gear 86 is retracted by one tooth as hereinafter described. Friction drive means is provided for connecting the bevel gear 86 to the rotatable nozzle housing 31 and consists of a split ring 87 disposed in an annular recess 88 in the bevel gear 86. The ring 87 is similar to the ring 77. A pin 89 is mounted in the housing 31 and extends into the space (not shown) between the ends of the ring 87 and is driven by the ring 87 which is driven by the bevel gear 86 so that the housing 31 is driven by the bevel gear 86.

A space 91 is provided within the gear carrier 19 and the ring gear 76 which is in communication with the planetary gear assembly which includes the internal ring gear 73, the. planetary gear 66, the drive pinion 64, the planetary gear carrier 69 and the other associated parts. The space 91 can be filled with oil through a hole 92 which is normally closed by a plug 93. An O-ring seal 94 is provided between the plug 93 and the base plate 51.

Means is provided for driving the propeller 46 and consists of a nozzle 96 which is adapted to supply fluid under pressure to vanes 97 carried by the propeller 46 to drive the propeller 46 in the desired direction as, for example, counterclockwise as shown in FIGURE 3. As can be seen in FIGURE 3, the nozzle 96 is carried by a fitting 98 and is adapted to be adjusted to any of a plurality of positions within a V-shaped opening 99 provided in the shroud 56. The fitting 98 is threaded onto a nipple 101 which is threaded into a projecting portion 16α formed as an integral part of the rotatable housing 16. The projecting portion 16α is provided with a large passage 102 which is always in communication with at least one of the openings 14 provided in the stem or stationary housing 10. The projecting portion is also provided with a bore 103 which is in communication with the nipple 101 and is also in communication with the passage 102. Means is provided for filtering or straining the fluid before it enters the passage 103 and consists of a cylindrical screen 104. One end of the screeen is disposed in a recess 106 which has one end opening into the passage 102 and the other end opening into the bore 103. The other end of the screen 104 is disposed in a bore 107 and is held in place by a screw 108 which has a downwardly depending cylindrical portion 108α which fits within the screen 104. An O-ring 109 disposed in a recess 111 is provided for establishing a fluidtight seal between the screw 108 and the projecting portion 16α.

Operation and use of the hydraulic tank cleaning apparatus may now-be briefly described as follows. Let it be assumed that the adapter 11 has been connected to a suitable source of cleaning fluid. Let it also be assumed that the tank cleaning apparatus with the line containing the cleaning fluid attached to the stem 10 has been lowered through the opening in the tank to be cleaned. The cleaning fluid is then supplied under a suitable pressure, such as 40 to 500 pounds per square inch, to the stem whence it flows through the passage 13 into the openings 14 provided in the stem. The cleaning fluid then travels in two directions. First, a small portion of the cleaning fluid travels into the passage 102 provided in the projecting portion 16α through the screen 104 and down through the bore 103 and out the nozzle 96 to cause a jet of the cleaning fluid to impinge upon the vanes 97 carried by the propeller 46 to cause rotation of the propeller. The rotation of the propeller 46 causes rotation of the shaft 47 and pinion 64 carried by the shaft. The pinion 64 drives the planetary gear 66. The planetary gear 66 engages the internal ring gear 73 and the differential gear 74.

3,464,632

The internal ring gear 73 is held in a stationary position with respect to the stem or stationary housing 10. The differential ring gear 74 is caused to rotate as the planetary gear 66 travels around the internal ring gear 73. Rotation of the internal ring gear 74 causes rotation of the rotatable housing 16 so that it rotates about the stem 10. Rotation of the housing 16 about the stem causes the bevel gear 86 to index or advance the bevel gear 84 carried by the gear carrier 19 so that the nozzle housing 31 and the nozzle 39 carried thereby are rotated about the cylindrical extension 26. Thus, it can be seen that at the same time that the housing 16 is rotating about a vertical axis, the nozzle 39 is rotating about a horizontal axis. The cleaning fluid passes from the inlet 12 through the openings 14 into the passage 27 through the openings 28 into the passages 42 and the passages 41 in the nozzles to provide jet streams which impinge upon the inside surfaces of the tank to wash the same.

Means is provided for progressively advancing the nozzles 39 so that they do not follow the same path as they rotate within the tank. This means ensures that progressive areas of the tank are washed even though the stem 10 is held in a stationary position. This means consists of differing numbers of teeth carried by the bevel gear 84 and the bevel gear 86 as hereinbefore described.

With the arrangement shown, it is possible to obtain many different types of speed of operation for the tank cleaning apparatus. The position of the nozzles 96 can be changed so as to change the direction that the jet stream coming therefrom impinges upon the vanes 97 of the propeller. Alternatively, the propeller itself can be changed to provide different types of vanes. A different size of nozzle can also be provided.

If additional speed changes are required, they can be obtained by changing the gears in the planetary gear assembly. As can be seen from FIGURE 1, the planetary gear carrier 69, together with the pinion gear 64 and the planetary gear 66, can be readily removed and a different assembly substitued therefor to obtain the desired gear ratio. If additional reduction gearing is required, a spur gear train can be provided between the shaft 47 and the pinion 64.

The use of the friction rings 77 and 87 are particularly advantageous. The friction ring 77, in combination with the pin 79, serves as a safety device to prevent stripping of the gears. In the event that the cleaning apparatus strikes an object or shock forces are applied to the cleaning device, the friction ring 77 slips in the differential gear 74. Similarly, the friction ring 87 permits the nozzle housing 31 together with the nozzles 39 carried thereby to be shifted without rotation of the bevel gear 86. In this way, the nozzles can be manually shifted to any desired angular position without rotation of the gearing. The friction ring 87 can also serve as safety means to prevent stripping of the bevel gears.

Another embodiment of the hydraulic tank cleaning apparatus is shown in FIGURE 4. It consists of a stationary, substantially cylindrical stem or stationary housing 121 which has an adapter 122. The upper end of the adapter is provided with external threads 123. An O-ring 124 is provided for establishing a seal between the adapter 122 and the stem 121. The adapter 122 is held in place by a set screw 126 threaded into the adapter 122 and engaging the stem or stationary housing 121. The set screw 123 is locked in position by a nut 127. The adapter 122 is provided with a flow passage 128 which is in communication with a flow passage 129 provided in the stem 121. The stem is provided with four vertically disposed openings 131 spaced around the circumference of the stem to provide balanced flow and which are in communication with the flow passage 129.

A rotatable housing 136 is rotatably mounted on the lower portion of the stem 121 by bushings 137 and 138. Both of the bushings 137 and 138 are provided with lugs (not shown) for preventing rotation of the same. Thus, ⁶ the bushing 137 is provided with a lug (not shown) which extends into the adapter 122, whereas the bushing 138 is provided with a lug (not shown) which extends into a bevel gear 139 secured to the lower portion of the stem 121. Sealing means is provided for each of the bushings and consists of O-rings 141 which are held in place by seal rings 142.

The rotatable housing 136 is provided with a cylindrical extension 144 which has a flow passage 146 which is in communication with an annular space 147 provided between the stem 121 and the upper portion of the rotatable housing 136 and which is in communication with the openings 131 provided in the stem.

A rotatable nozzle housing 148 is rotatably mounted upon the extension 144 by inner and outer bushings 149 and 151. These bushings are also provided with lugs (not shown) to prevent rotation of the same with respect to the cylindrical extension 144. Sealing means is also provided in the form of O-rings 152 and seal rings 153 for each of the bushings. A retaining plate 156 is mounted on the outer end of the cylindrical extension 148 and is secured thereto by screws 157. A pair of nozzle extensions 158 are formed as a part of the nozzle housing 148 and have nozzles 159 removably threaded therein. The nozzles 159 are provided with flow passages 161 which are in communication with an annular space 162 between the nozzle housing 148 and the cylindrical extension 144. The space 162 is in communication with horizontal openings 163 provided in the nozzle extension and which are in communication with the annular space 146.

Means is provided for causing rotation of the nozzle housing 148 on the cylindrical extension 144 and for also causing rotation of the rotatable housing 136 on the stationary housing 121 and consists of a multi-bladed propeller 166 secured to a shaft 167. A stator 168 which has a plurality of blades 169 mounted upon a hub 171 is disposed in the passage 129 in the stem or stationary housing 121 and is held in place by a snap ring 172. The shaft 167 may extend upwardly into the stator 168, if desired.

A packing nut 173 is mounted on the shaft 167 and is threaded into the lower extremity of the stem or stationary housing 121. An O-ring seal 176 provides a seal between the shaft 167 and the packing nut 173. The packing nut holds in place a packing gland 177 within the stationary housing and on the shaft 167.

The lowermost extremity of the shaft 167 is carried by a ball bearing assembly 178 carried by a bottom plate 179 which is secured to the lower extremity of the rotatable housing 136 by cap screws 181. An O-ring 182 is provided for making a seal between the bottom plate 179 and the housing 136. The bottom plate 179 is provided with a depending skirt-like portion 179α so that the hydraulic cleaning apparatus can be set upon a level surface while accommodating the cap screws 181 and also the oil filler cap 183 provided in the bottom plate 179.

A drive pinion 186 having helical teeth thereon is mounted upon the drive shaft 167 adjacent the lower end and drives a planetary gear 187, also having helical teeth. The angles of the helical teeth with respect to the shaft vary from 1° to 15°. The angle is normally chosen so that the axial thrust created is substantially equal to the axial thrust created in the opposite direction by the cleaning fluid striking the propeller 166. This makes it possible to eliminate the need for thrust bearings for the shaft 167. The planetary gear 187 is rotatably mounted upon a shaft 188 by a pair of ball assemblies 189. The shaft 188 is mounted in a planetary gear carrier 191 which is rotatably mounted upon the shaft 167 by a pair of ball bearing assemblies 192 disposed on opposite ends of the drive pinion 186.

The planetary gear 187 engages an internal ring gear 196 and also a loose differential internal ring gear 197. Both of the ring gears are provided with helical teeth to mesh with the helical teeth provided on the planetary gear 187. Means is provided for forming a friction drive

3,464,632 between the internal ring gear 196 and the bevel gear 139 of a type hereinbefore described and consists of a spilt ring 201 provided in an annular recess 202 in the gear 139. A pin 203 extends upwardly into the space between the ends of the split ring 201 and is mounted in the internal ring gear 196. The internal ring gear 196 is secured to the lower extremity of the stem 121 and has a fixed relationship thereto. An O-ring seal 204 is provided for establishing a seal between the internal ring gear 196 and the housing 136. A ball bearing assembly 206 is mounted on the shaft 167 and is carried by the internal ring gear 196. An additional O-ring seal 207 is provided in the internal ring gear and encircles the shaft 167 immediately above the bearing assembly 206. The differential internal ring gear 197 is frictionally secured to the housing 136 and rotates with the housing 136 by a split ring 208 mounted in a recess 209 in gear 197 and a pin 211 mounted between the ends of the ring 208 and formed integral with the bottom plate 179.

The bevel gear 139, which is normally held in a stationary position by the friction means consisting of the ring 201 and the pin 203, drives a bevel gear 213 which is formed integral with the nozzle housing 148.

The space 214 provided below the internal ring gear 196 and above the bottom plate 179 is normally filled with oil through the plug 183.

Operation of this embodiment of the hydraulic tank cleaning apparatus may now be briefly described as follows. Let it be assumed that the hydraulic tank cleaning apparatus has been connected to a suitable source of fluid such as that hereinbefore described in conjunction with the embodiment of the invention shown in FIGURES 1-3. The cleaning fluid will flow through the passage 128 into the main flow passage 129, into the stem or stationary housing, through the stator 168 to drive the propeller 166. The propeller 166 drives the shaft 167 to cause rotation of the pinion gear 186. The pinion gear 186 drives the planetary gear 187 which engages the internal ring gears 196 and 197. Since the internal ring gear 196 is held in a stationary position with respect to the stem 121, the differential ring gear 197 is caused to rotate as the planetary gear 187 travel around the internal ring gear 196. Rotation of the differential internal ring gear 197 causes rotation of the housing 196 on the stem or stationary housing 121.

Rotation of the housing 136 causes the bevel gear 211 carried by the nozzle housing 148 to be rotated about the cylindrical extension 144. Thus, upon operation of the propeller 166, the main housing 136 is rotated about a substantially vertical axis, whereas the nozzle housing 148 is rotated about a substantially horizontal axis. The cleaning fluid, after passing the propeller, passes through the openings 131 into the annular space 147 and into the cylindrical extension 144 and then out through the openings 163 to the space 162 and through the nozzle 158. The apparatus will thus provide two jet streams of high velocity which impinge upon the inside surfaces of the tank to wash and cleanse the same. As hereinbefore explained, the helical gearing produces an axial thrust which counteracts the axial thrust produced by the propeller 166. The remainder of the operation of the apparatus is substantially identical to the operation of the apparatus hereinbefore described.

It should be apparent that the particular gear arrangement and the friction drive arrangement provided in this embodiment of the invention can also be utilized in the embodiment of the invention disclosed in FIGURES 1—3.

It is apparent from the foregoing that there has been provided a new and improved hydraulically operated tank cleaning apparatus which is relatively small and compact which permits it to be utilized in tanks having small holes or openings therein. In addition, it is constructed in such a manner that there is no opportunity for the high pressure cleaning solutions being utilized to enter the gear box. The gear box is completely sealed at atmospheric pressure. In the first embodiment, there are no moving parts passing through the gear box and which come into contact with the cleaning fluid being utilized by the cleaning apparatus. The apparatus is driven by a propeller which is out of the main flow of the cleaning fluid and the shaft carrying the propeller is also outside of the main flow path of the cleaning fluid. Thus, there is provided a main flow passage for the cleaning fluid which is unimpeded by propellers and the like. In the embodiment shown in FIGURE 4, an improved model has been provided which is particularly suitable for simplified manufacturing purposes. As shown in FIGURE 4, a propeller can be disposed within the main flow stream for the cleaning fluid while retaining many of the advantages of the embodiment shown in FIGURES 1-3. The planetary gear train particularly makes it possible to make the cleaning apparatus small and compact.