Automated tank cleaning and monitoring device

[0001] The present invention relates generally to tank cleaning systems and devices, and in particular to tank cleaning systems and devices that are particularly well adapted to controlled tank cleaning and process evaluation.

Background of the invention [0002] Liquid storage tanks are used in many industrial processes such as the production and processing of food and chemicals, the production of pharmaceutical preparations, the production of wine, fermentation of materials and the like. It is often critical to ensure that unwanted residues and contaminants do not occur inside the tank. For example, in a tank, which is usually filled to a certain level, there may be a "bath ring" around the inner circumference of the tank at the height to which it is most often filled. It is also possible to accumulate residue in the form of a coating or other deposits occurring on the blades, mixers or other devices inside the tank. It is also known that there are deposits or residues in the tank inlets and outlets, and they may again be in the tank contents when the tank is used later.

[0003] Undesirable contaminants in the tank may have a negative impact on the final quality of the processed or manufactured product. Insufficient cleaning of the inside of the tank may also violate regulations in force in some industries, for example when manufacturing pharmaceutical preparations. The interiors of such tanks are therefore usually cleaned from time to time, for example after each batch processing, to ensure product quality and compliance with all applicable regulations. [0004] Cleaning devices and equipment are available that clean the inside of tanks and other vessels from residues and sediments using a solution known as impact cleaning. One of the popular cleaning systems uses a device that is introduced into the tank. The inserted device can be placed in the tank permanently or temporarily, it is usually attached to the tank via a flange. The rod-like elongated element being part of the device located inside the tank supports the rotating spray head attached at its inner end. The elongated rod-like element has a fixed tubular housing supporting the internal rotary shaft, ensuring the rotation of the spray head around the axis of the shaft. Furthermore, the spray head is usually connected via a gearbox to a fixed housing in such a way that when the spray head rotates about the axis of the roller, it also rotates around an axis perpendicular to the shaft.

[0005] The relationship between the rotation of the roller and the rotation of the spray head in a direction perpendicular to the roller depends on the gear ratio connecting the spray head to the fixed housing. The ratio is usually chosen in such a way that the combination of the given orientation and position of the spray head is repeated only after many rotations of the roller. In this technique, subsequent traces of spraying the interior of the tank are shifted with each rotation of the roller, which ensures that substantially all parts of the interior of the tank are sprayed at some point during the cleaning process.

[0006] Such a system is simple and has high mechanical strength, but it causes some inefficiencies, and depending on its mode of operation, decreases in its effectiveness are possible. Regarding efficiency, it should be understood that known systems similar to those described above are not adapted to deliver a constant volume of cleaning solution to all parts of an evenly soiled surface. Systems similar to those described above are also not adapted to supply a specific volume of cleaning solution to specific parts of the interior of the tank due to the known heavy soiling of said parts.

[0007] For example, in the case of annular sludge located on the level line into which the tank is filled, despite the known part containing said filling line, where the dirt is larger, existing systems do not allow the operator to adapt the cleaning operation in such a way as to ensure more intensive cleaning these parts. In typical use, the systems described above may therefore cause too intensive cleaning of some parts of the tank and insufficient cleaning of other parts of the tank. Although it is possible to extend the cleaning time to ensure that the most dirty parts of the inside of the tank are properly cleaned, this leads to additional losses of time, cleaning fluid and energy for lightly soiled surfaces.

[0008] US 6 039 056 discloses a tank cleaning system in which a nozzle sprays a jet of cleaning fluid onto the surface to be cleaned. Each nozzle can rotate around two axes. Tank cleaning can be adapted to the needs due to the use of two drives independently of each other, which allows control of the rotational movement of the nozzle around two axes.

[0009] US 2005/0236021 discloses a self-propelled floor cleaner that can also be used for watering indoor plants.

OBJECTIVES AND SUMMARY OF THE INVENTION [0010] According to a first aspect of the invention, a tank cleaning system is disclosed having all the features of claim 1.

[0011] According to a second aspect of the invention, there is disclosed a method of cleaning a tank comprising the steps described in claim 8.

[0012] The object of the present invention is to provide a tank cleaning device adapted to more efficient and effective cleaning of the tank. A related object of the invention is to provide said tank cleaning device ensuring minimizing the time and cost of cleaning the tank.

[0013] Another object of the invention is to provide a tank cleaning device as characterized above that can be easily monitored to ensure confirmation of proper cleaning of the tank. In this context, a related object of the invention is to provide a tank cleaning device that allows control of spray head operation and monitoring its operation, while maintaining the mechanical simplicity and strength provided by a solution comprising a spray head with a gear.

[0014] Another object of the invention is to provide a tank cleaning device of the above type which can be automatically controlled when cleaning the tank, taking into account one or more properties of the tank being cleaned.

[0015] Still another object of the invention is to provide a tank cleaning system comprising a plurality of tank cleaning devices of the above type. In this context, the related object of the invention is to provide a tank cleaning system providing coordinated control of multiple tank cleaning devices and monitoring their operation.

[0016] Other objects and advantages of the invention will become apparent upon reading the detailed description of the invention set forth below with reference to the drawing, in which:

BRIEF DESCRIPTION OF THE DRAWINGS [0017]

Fig. 1 is a partial perspective view of an exemplary tank comprising a tank cleaning system operating in accordance with the present invention;

Fig. 2 is an enlarged perspective drawing of the system cleaning part of the system illustrated in Fig. 1;

Fig. 3 is a diagram illustrating exemplary connections in a tank cleaning system according to the invention;

Fig. 4 is a longitudinal vertical section of the tank cleaning device of Fig. 2, which further comprises a control part;

Fig. 5 is a flowchart of a procedure illustrating processes and data flow while performing the tank cleaning procedure according to the invention; and Fig. 6 shows a longitudinal vertical section of the tank cleaning device providing a linear degree of freedom about the axis of rotation of the roller.

[0018] Due to the susceptibility of the invention to various modifications and the use of alternative constructions, the drawings show an exemplary embodiment thereof, which will be described in detail below. It should be understood, however, that the disclosed form of the invention is not intended to limit it, on the contrary, the purpose is to include in it all modifications, alternative constructions and equivalent solutions which are covered by the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0019] With reference to the drawings, an exemplary tank cleaning device 10 is shown, which is used in particular for the selective cleaning of the inner surface of the tank 20. The tank cleaning device 10, which will be discussed in more detail with reference to Figs. 2 has a pipe part 30 penetrating into the tank 20 and an actuating part 40 which is located outside the tank.

[0020] The inner 30 and outer 40 parts of the tank cleaning device 10 are mechanically connected to each other and in a manner that ensures fluid flow, which will be discussed in more detail later in the description, the inner space of the tank 20 is, however, sealed off from the external environment by means of an annular seal , for example, a deformable or compressible flange in place 50 of tank 20, wherein the inner tubular portion 30 of the cleaning device 10 enters the reservoir 20.

[0021] During the cleaning process, the tank cleaning device 10 sprays the cleaning fluid into the walls of the tank 20 in the form of one or more streams indicated by reference numeral 60. When spraying streams 60 onto the walls of the tank 20, the tank cleaning system changes the impact of the streams on the tank 20 to finally clean essentially the entire inner surface of the tank 20, including the internal parts of the flanges, blades, mixers and other components and equipment connected to the interior tank 20 in a manner that ensures the flow of liquid.

[0022] The way in which the positions of the point (s) of impact of the streams on the inner surface of the tank 20 are controlled will be discussed in more detail with reference to Fig. 4. It should be understood that the impact of the cleaning fluid may be in some parts of the interior tank 20 is direct, while for other parts the impact may be indirect. For example, parts of the inner surface obscured for stream (s) 60 by fittings or other surfaces of the reservoir may be sprayed indirectly, not directly.

[0023] As noted above, the exemplary tank cleaning system 10 includes a tubular portion 30 penetrating into the reservoir 20 and an actuation portion 40 that is located outside the reservoir 20. The inner 30 and outer 40 parts of the cleaning device 10 are separated by a flange 100 which is used is also for attaching the device 10 to the tank wall.

[0024] The actuating part 40 located outside the tank 20 also has an inlet 110 intended for introducing the cleaning fluid at increased pressure. The source of the cleaning fluid supplied to the inlet 110 is usually in the form of a pressure vessel, and thus accurate control of the flow rate of the cleaning fluid at increased pressure through the device 10 is often difficult. The source of fluid can also be a pump connected to an inlet 110 according to the invention, but it is not required in all embodiments. The introduced fluid is moved to the inner part 30 of the device 10 and ejected into the tank to be treated (Fig. 1), which will be discussed in more detail below. The actuation part 40 located outside the tank 20 further has an exposed end of the shaft 120 designed to mechanically receive energy from a rotational energy source (not shown in Fig. 2). A pneumatic motor or electric motor assembly and a toothed release gear 120 are connected to the shaft passing through the flange 100 into the interior of the tank. A rotational position sensor is attached to the shaft, the mounting method used ensures detection of the rotational position of the shaft. The point at which the shaft exits the flange is sealed from the inside of the tank and from the inlet 110 in such a way as to ensure that the rotational movement is transferred to the interior of the tank without the contents of the tank or cleaning fluid leaking from the device.

[0025] The inner part 30 of the device 10 further has a stationary tubular housing 140 and a rotatable end part 130. The rotatable end part 130 further has a spray head 150 on which one or more spray nozzles 160 are located.

[0026] The stationary tubular housing houses a shaft (not shown) that is mechanically connected to the air motor or electric motor 120 via a sensor to provide rotational transmission. The visible outer casing 140 has an internal channel containing a shaft that is connected to the inlet 110 in a manner that ensures fluid flow. It will be appreciated that in order to allow the pressurized fluid to flow to the rotary shaft within the housing 140, it is possible to use one or more rotary seals (not shown).

[0027] As noted above, an increased pressure fluid is supplied to the spray head 150, which is ejected from the spray nozzle (s) 160. When the increased pressure fluid is ejected from the nozzle (s) 160, the spray head 150 is rotated about a vertical axis A (i.e. internal shaft axis) using an exposed shaft connected to a pneumatic motor or an electric motor 120. The rotation of the spray head 150 around the vertical axis A, in turn, causes the spray head 150 to also rotate around the perpendicular axis B due to the connection of the spray head 150 to the housing via a gear.

[0028] The inability to monitor and control the position and orientation of the spray head resulted, however, in varying degrees of inefficiency and / or inefficiency of the process. As discussed above, until now it has been necessary to extend the time or intensity of the cleaning cycle to ensure that the most dirty areas are properly cleaned. However, this often resulted in excessive cleaning of lightly soiled areas and associated loss of time for the process and cleaning fluid.

[0029] According to the invention, the position and orientation of the spray head 150 can be selectively or automatically set and monitored in a manner that ensures efficient and effective cleaning as well as confirmation of the correct course of the process. In the embodiment of the invention illustrated, the position and orientation of the spray head 150 is monitored using a rotational position sensor and set according to a number of parameters regarding the shape of the tank and its internal environment in such a way as to ensure optimal cleaning.

[0030] An exemplary system according to the invention can be generally seen with reference to the diagram shown in Fig. 3. The system 200 includes data sources and data outlets connected together to provide control of the tank cleaning process. The course of the process is controlled by the control module 220. The control module 220 is in the form of a computer-implemented module saved in the form of computer-implemented instructions on a medium that can be read by a computer. The control module can be implemented in the form of executable code, interpretable code, script or other type of code suitable for this purpose.

[0031] The control module 220 is operated using the user interface 230. According to one aspect of the invention, the cleaning process can be at least partially controlled also by the user interface 230. The user interface may include a keyboard, touch screen, mouse, pen, module voice commands or other input mechanism, it may also contain a screen or other output device providing communication with the user. The user interface may also contain an alternative input device such as a CD-ROM drive, DVD drive, portable memory interface, etc., for the purpose of user input and / or to provide data to the user.

[0032] During the operation of the invention, the control module 220 receives process data from the database 280 and controls one or more parameters of the cleaning process on its basis. To this end, the control module is connected to the actuator of the spray head 270 in a manner that ensures communication. The spray head actuator 270 controls the position (and therefore the orientation) of the spray head.

[0033] In one aspect of the invention, the actuator of the spray head 270 is in the form of a drive unit, for example a pneumatic motor, which drives the spray head shaft of the cleaning device as described above. In another aspect of the invention, the actuator of the spray head 270 is in the form of a braking unit, e.g. a disk, drum or electrodynamic resistance module, providing control of the rotation of the shaft by applying braking.

[0034] Also according to the invention, the control module 220 is also optionally connected to the cleaning fluid source 250 in a communication manner to control the fluid related parameter supplied to the spray head. Control module 220 typically controls the pressure at which fluid is supplied to the head, which provides control over the pressure and / or flow rate of fluid ejected from the spray head nozzles.

[0035] The control module 220 controls the operation of the head actuator 270 and optionally the fluid source 250 in accordance with real-time process data as well as pre-stored process environment data as shown in data field 210 of database 280. To this end, the database data 260 is connected so as to communicate with the source 260 of information regarding the position and orientation of the spray head. Said data source includes an independent rotary position sensor such as an optical encoder (not shown) in accordance with one aspect of the invention, but it is also possible to use a different type of sensor. For example, it is possible to use a photoelectric detector associated with a gear tooth, bore or other permeable or reflective bore or element providing rotational motion detection.

[0036] The rotational position sensor is preferably located on the drive shaft of the device 10. Placing the rotational position sensor in this way, rather than on the motor shaft or the spray head itself provides several advantages. For example, the drive shaft rotates at a much lower rotational speed than the drive motor, the rotational position sensor is located outside and does not need to be as tightly sealed as in other cases. The need to send electrical signals from the head through the rotary seal has also been eliminated.

[0037] Since the rotational position sensor tracks two parameters (position and orientation) associated with the initial position / orientation as well as with the system gear, a translation table or translation algorithm is used to translate the data obtained at the output of the rotational position sensor into position and orientation data. The table can be implemented as part of data source 260 or can be saved in database 280. In the first case, location and orientation are entered into database 260 in a form ready for use by the process control module 220. In the latter case, the data is translated after it is received by database 260, this being done if necessary or before saving them. [0038] As noted above, according to an optional aspect of the invention, the process control module 220 can control the operation of the cleaning fluid source 250. To this end, the database 280 is connected in a manner that ensures communication with the data source 240 providing data regarding one or more parameters of the cleaning fluid source. Exemplary parameters include fluid pressure, amount of fluid remaining, flow rate, etc. Such feedback allows more accurate control of the operation of the cleaning fluid source by the process control module 220.

[0039] Regardless of whether or not the control module 220 controls the operation of the fluid source, the fluid source data is useful in ensuring that the cleaning process runs correctly. For example, an unexpected increase in pressure provided by the source and / or a decrease in fluid flow rate may indicate clogging of the nozzle and, consequently, a failure of the cleaning process. In one aspect of the invention, it is important for the system to signal a failure, so that it is not mistakenly assumed that the cleaning process has ended correctly.

[0040] As noted above, in one aspect of the invention, the control module 220 controls the operation of the actuator of the head 270 and optionally the operation of the fluid source 250 in accordance with the real-time process data as well as pre-stored process environment data. Previously saved data may include any data that affects the cleaning process. Examples of previously recorded data include a translation table of the drive shaft movement, drive shaft parameters (e.g. current / voltage / air pressure as a function of rotational speed / torque), data on tank geometry (e.g. dimensions, shape, internal characteristics such as blades, annular fill level lines, manholes, flanges, inlet and outlet ports etc.) and data on the fluid flow rate (e.g. cleaning fluid pressure as a function of flow rate, nozzle performance characteristics, etc.).

[0041] After a general discussion of the tank cleaning system scheme according to one aspect of the invention, the system will be discussed at the physical level with reference to the partial perspective section shown in Fig. 4. The tank cleaning system 300 includes a tank cleaning device 310 as shown in Fig. 2 (element 10), which has a tubular part 320 (Fig. 2, element 140) extending into the tank and an actuating element (Fig. 2, item 40), flange 360 ​​(Fig. 2, item 100), inlet 380 (Fig. 2, item 110) for injecting high-pressure cleaning fluid, exposed end of roller 390 (Fig. 2, item 120) and rotatable an end portion (Fig. 2, item 130) comprising a spray head 410 (Fig. 2, item 150) on which one or more spray nozzles (Fig. 2, item 160) are located.

[0042] In a partial perspective cross-section of Fig. 4, a roller 430 in the stationary tubular housing 320 is further visible. Said roller 430 transmits rotational movement from exposed end of the roller 390 to a rotary head comprising a spray head 410. A toothed ring 440 located at the end of the tubular housing 320 is meshed with the gear wheel 450 attached to the head 410 to rotate the head 410 in the manner described above. Specialists in this field are familiar with the principles of device 310. The device configured in the manner described is the tank washing apparatus model AA190 manufactured by SPRAYING SYSTEMS COMPANY from Wheaton, Illinois.

[0043] In order to control the operation of the tank cleaning device 310, the engine and reduction gear assembly 460 is mechanically connected to the shaft 430 via an exposed end 390. In the example shown, the assembly 460 is a pneumatic motor with a gear, but you should be aware of this that other types of engines and propulsion systems can also be used.

[0044] In the example shown, the assembly 460 is attached to the shaft 430 via a rotary sensor 470. The rotary sensor can be any type of sensor, but preferably it is a high resolution rotary sensor (e.g. 17 bit) that records both the absolute position of the shaft and and the number of turns made. The measurement of the absolute position of the shaft and the number of revolutions performed can be carried out using the rotational position sensor 470 alone, the control system 510 alone, or a combination of the two elements mentioned.

[0045] The rotary position sensor sends output to control system 510 via connection 490. Control system 510 may be in the form of a programmable logic (PLC) containing control logic (i.e. instructions that can be executed by a computer) during the course of cleaning operations. Alternatively, the control system may be in the form of a computer, workstation or other computing device designed to execute control logic instructions (e.g., implementing the control module 220).

[0046] In the example shown, the control system 510 controls the operation of the motor of assembly 460, and thus of the shaft 430, which is done by controlling the air pressure supplied to the assembly 460. The pressure of the air supplied to the assembly 460 is controlled by means of an electronically controlled pressure regulator (I / P) 520, into which inlet 540 is pressurized air, and outlet 550 is provided with controlled pressure. Departure

550 it is connected in turn via channel 560 to assembly 460.

[0047] The pressure regulator 520 receives the electric control signal transmitted by the control system 510 via an electrical connection 530. The control signal is in the form of any type of signal and / or protocol suitable for this purpose, but in a preferred embodiment of the invention the control signal is in the form of a control signal from 4-20 mA open feedback loop. The pressure regulator, in turn, controls the air pressure supplied through the outlet 550. The control signal received via connection 530 is therefore used to control the speed of assembly 460 and shaft 430. Although not shown in Figure 4, control system 510 also optionally controls one or more parameters of the cleaning fluid supplied to inlet 380, as discussed above.

[0048] The cleaning process according to various aspects of the invention may be carried out automatically when a triggering event occurs or a specified time has elapsed. For example, the cleaning cycle can be started at the end of the processing step in which the tank is used. Alternatively, the cleaning process may take place according to a predetermined schedule, e.g. every 24 hours. The cleaning process can also be started by the user.

[0049] The flow chart of Fig. 5 illustrates the steps taken according to the invention to carry out the tank cleaning procedure using the tank cleaning device and cleaning system as described above. The cleaning process is initiated in step 610 of process 600, e.g., by pressing the button by the user on a schedule or due to another triggering event. The control module then determines the initial position (e.g., axial position relative to shaft 430) and orientation (e.g., on an axis perpendicular to shaft 430) of the spray head in the tank. In particular, step 620 reads the output status of the rotary position sensor described above and then stores it in a temporary or permanent memory, e.g. in database 280. In step 630, the recorded data from the rotational position sensor is translated into the position and orientation of the spray head. This translation can be performed using a translation or mapping table or using the algorithmic transformation described above.

[0050] Based on the specific position and orientation of the spray head, the tank cleaning system calculates in step 640 the location (s) of the jet impacts and the sweeping trajectories of the spray jets. In addition to data regarding the position and orientation of the spray head, this step also uses other relevant data, e.g. tank surface geometry data, cleaning fluid source data (e.g. fluid supply pressure), and fluid flow rate data that can be obtained from data field 210 of database 280. [0051] After calculating the impact location of the spray streams and sweeping trajectory, the relationship between the position of the spray head and the impact point is known. At step 650, this data is used along with other data to associate the position of the spray head with one or more cleaning parameters. For example, the pressure of the cleaning fluid and the duration of the jet influence the degree of cleaning achieved at a given location inside the tank. Therefore, adjusting one or both of these independent parameters has an effect on the cleaning process.

[0052] Additional data used in step 650 to calculate the relationship between the position of the spray head and one or more cleaning parameters may include data regarding both tank geometry and specific requirements for cleaning specific locations in the tank. For example, points further away from the spray head nozzles may be subjected to jets with a higher average impact force and / or longer spraying. Points requiring indirect spraying may also require a higher flow rate and / or longer spraying. Still another cleaning issue is the presence of annular fill lines and other areas that are heavily soiled, where such areas may also be subjected to streams with a higher mean impact force and / or longer spraying.

[0053] At step 660, the control module calculates the drive shaft control parameters and / or fluid supply control parameters that are required to perform cleaning in accordance with the cleaning parameters specified in step 650. For example, if the cleaning parameters indicate the need for additional cleaning at a specific position of the spray head, the control module generates signals causing the head to rotate in this position and / or increase fluid pressure in that position.

[0054] The control signals are calculated based on the response characteristics of the controlled element. For example, the motor control signals are therefore calculated based on the engine speed response to the control input (voltage, air pressure, etc.). Similarly, fluid pressure control signals are calculated, e.g., based on the response of the controlled element (e.g., electronically controlled pressure regulator) to the type of input signal (e.g., voltage or current (4-20 mA)).

[0055] After calculating the control parameters, the control module controls the position and orientation of the head between which there is a correlation related to the gear ratio of the gear located at the head, as shown in Fig. 4, and / or the pressure of the cleaning fluid, which is done by sending appropriate control signals in step 670. In this way, automated tank cleaning is carried out in an efficient and effective manner. For example, the control module may increase fluid pressure and / or slow or stop the spray head when the fluid is directed towards known heavily soiled locations.

In one aspect of the invention, after the cleaning cycle has been completed, the control module sends a cleaning confirmation signal in step 680. For example, the control module may emit an audible alarm signal through a loudspeaker or a piezoelectric element. Additionally or alternatively, it is possible to display via a user interface intended for the user a text and / or graphic message confirming the cleaning. In this way, the user can ensure compliance with applicable regulations and / or procedures regarding tank cleaning.

[0057] The above example of the invention has been described with reference to the single head cleaning system shown in Fig. 1, however, it should be understood that a plurality of such cleaning devices can be arranged in a single tank, which can be controlled according to the principles set out. For example, due to the acceleration of cleaning or the inability to effectively reach certain areas of the tank interior using a single spray head, it may be desirable to use two cleaning devices as shown in Figure 2. It is therefore envisaged that the described system can be used to control two or more heads located in a single tank in a way that ensures their coordinated operation.

[0058] The above examples have been described with reference to a drive system with a pneumatic motor rotating the drive shaft of a cleaning device, but it should be realized that it is possible to use any other drive systems suitable for this purpose instead. Other propulsion systems suitable for this purpose include, but are not limited to, stepper motors, DC motors (e.g., brushless motors), AC motors (e.g., controlled with frequency control), hydraulic motors (e.g., driven by a pressure transducer or control valve), etc. .

[0059] The position and orientation of the spray head may further be adjusted by reaction, for example using the reaction force originating from the stream ejected from the head. Particularly in this embodiment of the invention, but also in its other embodiments, it may be advantageous to use braking control rather than drive control. With a reaction cleaning device, accurate alignment may be more difficult than with shaft driven devices, but accurate braking control can be provided by using a disc or band brake, an electrodynamic resistance module or other controllable braking mechanism. In one aspect of the invention, controlled braking is combined with accurate position sensing to provide accurate control of the position and orientation of the spray head.

[0060] As regards the reaction cleaning device, the spray head can be attached in a way that allows it to rotate only in one plane. Generally speaking, one or more fluid outlets in the head are shaped in such a way as to ensure the desired distribution of spray jets when the device rotates. Regarding verification of proper tank cleaning, in one embodiment of the invention monitoring of the head speed and rotation is carried out.

[0061] With respect to the turbine-driven tank cleaning device, the drive mechanism and the measuring mechanisms may be located inside or outside the tank. For example, it is possible to use an internal drive element and an internal rotation sensor as discussed herein. In this example, the necessary grommets include at least an electric grommet for receiving sensor output and a fluid supply grommet for providing fluid used for providing rotation and cleaning.

[0062] The device shown in Fig. 2 can be moved in two interrelated dimensions, in alternative aspects of the invention it is possible to provide movement in other dimensions. For example, in another aspect of the invention, a linear degree of freedom is provided along the axis of rotation of the shaft. This solution is shown in Fig. 6.

[0063] The tank cleaning device 700 is similar to that of Figs. 2 (item 10) and 4 (item 310), but has an additional degree of linear freedom of movement along the axis of the rotating shaft 720. In the example shown, the tubular housing 750 housing the rotary the roller 720 is in particular slidably connected to the flange 740, which is tightly attached to the tank wall (not shown). In addition to the rotary seals discussed above, which allow the drive shaft 720 and the spray head 770 connected to the fluid inlet 760 to rotate in a manner that ensures fluid flow, a bellows 730 or other sealing mechanism with the possibility of sliding movement is used to allow the housing to slide 750 to flange 740 in a way that ensures leak tightness.

[0064] The linear position of the housing 750 relative to the flange 740 is controlled by the control module described above so as to change the point of impact of the fluid streams ejected from the nozzles 780. The actuator (not shown in the drawing) used to change the linear position of the housing may be in the form of a mechanism hydraulic gear mechanism or other mechanism suitable for this purpose.

[0065] The discussion provided generally relates to the cleaning of closed tanks and housings, but it should be understood that the invention is not so limited. For example, the invention can also be used to clean tanks and other open tanks. To avoid ejecting excessive amounts of fluid from the open portion of the reservoir, fluid flow can not only be slowed down in some orientations, but also stopped completely if desired. In particular, but not exclusively, in the case of a head with one nozzle or one outlet, stopping the fluid flow when spraying would cause it to be thrown out of the tank, saves cleaning fluid and avoids unwanted clutter.

[0066] It will be appreciated that the above description applies to examples illustrating the preferred configuration of a tank cleaning system. It should be noted, however, that the details of other implementations of the invention may differ from the above examples. As noted earlier, all references to the invention should be construed as references to the specific example of the invention which is discussed herein, and are not intended to introduce any limitations on the general scope of the invention. All distinctions and omissions relating to certain features of the invention are intended to indicate the absence of a favorable solution for these properties, and not to exclude them completely from the scope of the invention, unless otherwise indicated.

[0067] The use of terms indicating a concrete or indefinite form in the context of the description of the invention (in particular in the context of the following claims) is intended to include both the plural and singular, unless otherwise indicated or clearly not apparent from the context. . The terms "consists", "possesses", "includes" and "includes" should be considered as open terms (i.e. in the sense of "includes but not limiting"), unless otherwise stated. The value ranges cited here are intended to provide only a shortened way to separately cover each of the values ​​within the scope, unless otherwise indicated, and each separate value belongs to the description as if it were quoted separately. All the methods described herein can be carried out in any order that can be used, unless otherwise indicated or clear from the context. Any of the examples used and all examples as a whole as well as the indicative examples (for example, "such as") are intended solely to better illustrate the invention and do not limit the scope of the invention, unless otherwise indicated. None of the terms used should be taken as indicating any element not falling within the scope of the claims, but essential for implementing the invention in practice.

[0068] The invention thus includes all modifications and equivalents of the invention as defined in the appended claims within the scope of the applicable provisions. The invention further includes any combination of the elements described above and any possible variations thereof, unless otherwise indicated or clear from the context.