DE1216249B - Filtration device, especially for ship drainage systems - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

BOId

German class: 12d-27

Number: 1216 249

File number: B 62844 VII b / 12 d

Filing date: June 9, 1961

Opening day: May 12, 1966

The invention relates to a filter device, in particular for ship drainage systems, consisting of of two filters arranged next to each other with shut-off devices in between, which are connected in series of the two filters in opposite flow directions for the purpose of rinsing one filter each with the help of a pump.

In a known filter arrangement of this type, a single shut-off device is connected between the filters, which has an inlet and two drains. It can optionally be in three different positions to be brought. In the normal position, the two filters are connected in parallel; so that the dirty water flows through both filters at the same time.

In the second position, the two filters are connected in series. The dirty water is in the clarified first filter, then flows for the purpose of backwashing in the second filter and leaves the arrangement via the drain to which a clarifier to collect the flushed from the second filter Dirt can be connected. In the third position the two filters are in opposite directions Direction connected in series. The dirty water only enters the previously cleaned water Filter on and the clear filter then rinses the other filter. In all cases there is a direct, externally inaccessible connection between the two filters at one end of the same, the the filtrate flows through either in one or the other direction.

Although this arrangement enables constant, uninterrupted operation of the filtering device, but the activation of the pump required in every case encounters certain difficulties. the As far as possible, the pump should not have dirty water flowing through it so that it does not become clogged and damaged. Furthermore, the liquid must always flow through it in the same direction; otherwise pumps are connected in parallel and working in opposite directions with corresponding pumps Reversal measures necessary. In the case of the known device just described, however, occurs during the cleaning periods in which the two filters are connected in series, only Dirty water at the inlet and the outlet of the arrangement, so that the immediate switch-on a normal pump that is not suitable for waste water is possible.

The object of the invention is to provide a remedy here. For this purpose, the filter device according to the invention of the type specified at the beginning is a filter device, in particular
for ship drainage systems

Applicant:

John P. Brydon, Vancouver, Columbia (Canada)

Representative:

Dipl.-Ing. G. Weinhausen, patent attorney,

Munich 22, Widenmayerstr. 46

Named as inventor:

John P. Brydon, Vancouver, Columbia (Canada)

Claimed priority:

Canada 9 June 1960 (800 734)

characterized in that the two shut-off devices in the connecting lines between each other corresponding Have filter connections, their own inlet connection and their own turn-off connection in such a way that that alternately the connection of one of the two associated filter connections with the inlet and the other is possible with the drain, so that between the drain of the clear filtrate and its Re-entry into the filter to be backwashed through which clear liquid always flowed in the same direction Pump is switched on.

Thanks to the invention, the flow of the clear filtrate from the first filter and the inlet to the The filter to be backwashed is accessible to the outside, so that the two filters are constantly connected in series can stay and so that one filter is constantly self-cleaning. Even so, the pump is clear liquid always flows through it in the same direction. ·

A fully automatic operation is preferably made possible by the fact that when a certain Pressure difference at the connections of the first of the two series-connected filters the two shut-off devices are automatically switched over at the same time, so that the sequence of Series connection is reversed. The switching rhythm is determined by the actual drop the filter performance and not determined by a more or less arbitrarily determined period of time. The filter can be switched, for example, electrically or hydraulically.

609 568/365

The invention is particularly suitable for ship drainage systems because the Filtrieremrichtung on an inaccessible part of the ship can be accommodated, with the dirty water overboard drains. ·

The invention will now be described with reference to the drawings. It shows

F i g. 1 the schematic representation of an embodiment of the filter system according to the invention,

Fig. 2 is a partially sectioned representation 'ίο a filter system with electrical actuation,

FIG. 3 is a circuit diagram of the control device for actuating the system according to FIG. 2,

F i g. 4 an oblique view of another filter system according to the invention with hydraulic actuation,

FIG. 5 shows a partial section of the device according to FIG. 4 along line 5-5,

F i g. 6 shows a partial section along the line 6-6 in FIG. 5 together with a representation of the control cycle,

Fi g. 7 the schematic representation of a further filter system according to the invention with hydraulic Actuation and

Fig. 8 is a schematic representation of the hydraulic Control device for the automatic actuation of the systems according to FIG. 4, 5 and 7.

The basic principle of the invention is to be based on FIG. 1 will be explained.

Fig. 1 shows two filter devices 1 and 2 which contain filters not shown. The filter device 1 is provided with inlets and outlets 3 and 4 and the filter device 2 with inlets and outlets 5 and 6. The inlets and outlets 3 and 4 are arranged so that the liquid entering one inlet must flow through the filter before it flows out through the outlet. The same applies to the inlets and outlets 5 and 6. The inlets and outlets 3 * and 6 are connected by a fitting 7 and the inlets and outlets 4 and 5 by a fitting 8. Shut-off elements 9 and 10 are located in the fittings. An inlet 12 and an outlet 11 are connected to the fitting 7, and an inlet 13 and an outlet 14 are connected to the fitting 8. A pump 15 is connected with the suction side to the outlet 14 and with the pressure side to the inlet 13. The shut-off devices 9 and 10 are arranged in the fittings 7 and 8 in such a way that a direct flow of liquid between the inlets and outlets 3 and 6 or 4 and 5 is impossible. Furthermore, the shut-off devices 9 and 10 prevent a direct flow of liquid between the inlet 12 and the outlet 11 or the inlet 13 and the outlet 14. The inlet 12 is connected to a pipeline which is immersed in the liquid to be filtered.

The device shown in Fig. 1 works as follows: In the solid position of the shut-off devices 9 and 10, the liquid to be cleaned is sucked in through the inlet 12 and flows through the fitting 7, the inlet 6, the filtering device 2 and the outlet 5 in the Direction of arrow. The liquid exiting through the outlet 5 has been clarified because the foreign bodies previously carried along in the liquid were retained in the filtering device 2. The liquid now passes from the outlet 5 through the fitting 8 into the shut-off element 10, the outlet 14 and the Pump 15 and is fed back to fitting 8 through inlet 13. The liquid then passes into inlet 4 and in the direction of the arrow through filtering device 1. The clear liquid flowing through filtering device 1 removes the foreign bodies contained therein from the filter of this device, ie , exiting the outlet 3 of fluid containing entrained foreign matter. This contaminated fluid flows through the valve 7 and the obturator 9, and is discharged as Abfalfflüssigkeit through the outlet 11. thus, while the filtering device 2 entrained particles removed from the liquid and dä for ensures, that the pump 15 delivers pure liquid, the filter of the Filtriervo Direction 1 cleaned automatically because pure liquid flows through it. If the filter of the filtering device 2 is contaminated and no longer has a sufficient cleaning effect, the rotary slide valves 16 and 17 of the shut-off devices 9 and 10 must be in the dashed position in FIG. 1 can be brought. This reversal can be carried out automatically in the manner described below. In the second position, the fluid path is as follows: inlet 12, shut-off element 9, fitting ?, inlet 3, filter 1, outlet 4, fitting 8, shut-off element 10, outlet 14, pump 15, inlet 13, shut-off element 10, fitting 8, inlet 5, filter 2, outlet 6, valve 7, shut-off element 9 and outlet 11. In the second position, the filter of the filtering device 1 is used to clarify the liquid sucked in through the inlet 12, while the filter 2 is cleaned by the pure liquid flowing through. As you can see, only the filters 1 and 2 change their tasks when the rotary valve 16 and 17 are switched, while the direction of rotation of the pump does not change and the liquid to be clarified is constantly fed through the inlet 12 and discharged through the outlet 11.

The embodiment of the invention just described is particularly suitable for a ship drainage system. In the various hatches of the ship there is a device according to the invention and the one emerging from the outlet 11 Waste liquid is discharged overboard. The facility is special for such an application suitable because the changeover from one filter to the other is carried out automatically and the filter device therefore can be accommodated in inaccessible places.

A hydraulically operated reversing is shown in FIGS. 4, 5 and 6. The filtering device 1 and 2 each contain a strainer basket 2a . The filter device 1 is again provided with inlets and outlets 3 and 4, which are designed as flange pipes. The inlets and outlets 5 and 6 also represent flange pipes which open into the filtering device 2. The fitting 7 connected to the inlets and outlets 3 and 6 is designed as a flange tube which is screwed to the flanges of the inlets and outlets 3 and 6. The same applies to the fitting 8. The inlet 12, which consists of a flange pipe, is connected to the fitting 7. The outlet 11 (not visible in FIG. 4), which is designed in the same way, is connected to the fitting 7 diametrically opposite the inlet 12. The inlet 13 and the outlet 14 are also connected to the fitting 8. The inlet 12 can be connected to a pipe 12 'and the outlet 11 to a pipe 11'. Likewise, a pipe 18 is connected to the inlet 13 and a pipe 19 is connected to the outlet 14. In the self-cleaning embodiment, the pipe 18 is connected to the pressure side and the pipe 19 to the suction side of a pump,

as from Fig. 1 shows. The shut-off devices 9 and 10 are located in the fittings 7 and 8. These contain rotary slides 16 and 17, respectively. The rotary slides 16 and 17 are connected by a shaft 20 and lie directly on top of each other. The wave

20 is driven above by a hydraulic motor 21, which will be described in more detail below. The shut-off devices 9 and 10 with the slides 16 and 17 are constructed so that the shut-off device 9 is a noticeable direct liquid flow between the inlets and outlets 3 and 6 or between the inlet 12 and the process 11 prevented. The same applies to the shut-off element 10, as shown in FIG. 1 shows.

F i g. 6 shows a section through the hydraulic motor 21. This has a housing 22, one with it firmly connected stator 23 and a runner 24. The runner 24 is with a wedge 25 on the rotary valve shaft 20 attached. In the stand 23 openings 26 to 29 are provided, which have corresponding Pipelines 26 'to 29' with a control slide

30 are connected. The pipes 26 'and 29' are parallel to the pipe 32 and the pipes 27 'and 28' are connected to the pipe 31 in parallel. The pressure medium, preferably water, flows out or in the control slide 30 through the pipes 31 and 32, the pressure in the pipes 31 and 32 is different. In the position of the rotor 24 shown in FIG. 6, the pressure is in the pipe 32 and thus larger in the pipes 26 'and 29' than in the pipe

31 or in lines 27 'and 28'. Therefore, the liquid in the tubes 26 'and 29' flows into the chambers 33 and 34, fills these chambers and forces the runner 24 to act as shown in FIG. 6 position shown. So that the rotor 24 counterclockwise in the dashed position in FIG. 6, only has to the liquid pressure in the pipe 31 can be increased so much by the control slide that the liquid in the chambers 33 and 34 flows through the pipe 32. When this is done, the runner has 24 rotated counterclockwise and the liquid in chambers 33 and 34 is through the Openings 26 and 29 or the tubes 29 'and 26' flowed off, while those emerging behind the rotor 24 Chambers through the openings 27 and 28 are filled with liquid. The hydraulic motor

21 is sealed so that no liquid can escape from it. With the rotor 24 rotates Shaft 20 with rotary valves 16 and 17. As shown later on the basis of FIG. 8 is explained, the Control slide 30 automatically reversing so that the rotary slide 16 and 17 alternately in both operating positions come.

The embodiment shown in FIGS. 4 and 5 operates in the manner described for FIG. So when the rotary valve 16 and 17 are in one position, liquid is sucked in through the pipe 12 'and passes through the inlet 12, the shut-off element 9, the valve 7, the inlet 6, the filter 2 a, the outlet 5, the Fitting 8, the shut-off element 10 and the outlet 14 to the pipe 19. From here, the cleaned liquid can enter the suction side of a pump and comes from the pressure side of this pump through the pipe 18, the inlet 13, the shut-off element 10 and the valve 8 in the inlet 4, the filter of the filtering device 1, the outlet 3, the fitting 7, the shut-off element 9 and the outlet 11 into the drain pipe 11 '. In this position, the rotary valve 16 and 17. Thus, the filter 2 is a purified liquid, while the filter of the filtration device 1 is rinsed through the already purified liquid.

If the filter 2 a is clogged, there is a pressure difference on it, which can be determined and used to actuate the control slide 30. This rotates the rotary valve 16 and 17 in by means of the hydraulic motor 21 and the shaft 20

ίο their other location. For this purpose are in accordance with 3 and 7, tubes 35 and 36 with the sequence 14 or the inlet 12 connected. The pressure difference between those in tubes 35 and 36 Liquids are used to operate the control slide 30, as will be described below. When the pressure difference between the tubes 35 and 36 reaches a certain size, the Control slide 30 operated so that it the shaft 20 and the rotary valve 16 and 17 in their other

ao position rotates that is shown in FIG. 1 is dashed. In this position the filter device 1 is used for cleaning of the liquid flowing into the tube 12 ', while the filter of the filtering device 2 passes through the Purified liquid is flushed through the

"5 inlet 5 flows into the filter 2 a. The contaminated liquid emerging from the filter 2 α leaves the device through the outlet 11 and the pipe 11 '. The operation of the filters 1 and 2 depends on the position of the rotary valve 16 and 17, with one filter cleaning the liquid in one position while the other is rinsed, and in the other position the rotary valve 16 and 17 play the roles of the both filters are reversed. However, the liquid is always sucked in through the pipe 12 'and expelled through the pipe 11', ie

the function of the inlets and outlets connected to the fitting 7 is independent of the position the rotary valve 16 and 17.

An electrically operated reversal of the filter according to the invention is shown in FIGS. The in F i g. 2 is identical to that of FIG. 4. Therefore, in F i g. 2 only the upper part is shown. The only difference is that the hydraulic motor 21 is replaced by an electric motor 37 and the associated mechanical and electrical parts.

On the upper armature 8 there is a housing 38 which contains a gear 39. This is with the valve spindle, not shown, via a wedge or the like. Connected. The shaft of the motor 37 is Connected via a countershaft to worm 40, which meshes with worm wheel 39. With the gear 39 and the valve spindle 20 is connected to an insulating disk 41 for rotation, which is on best in fig. 3 can be seen and is provided with conductive segments 42. The Housing 38 two brushes 43, which are mounted on a brush bridge and with the insulating washer 41 and make contact with the conductive segments on it.

F i g. 3 shows a control device for the motor 37, which is dependent on the automatic reversal of the pressure differences between the pressure gauge tubes 35 and 36 is used. It contains a diaphragm valve 44 with a housing 45, in which a membrane 46 is located, which the housing 45 in two chambers 47 and 48 divides. The tube 36 stands with the chamber 47 and the tube with the chamber 48

35 (Fig. 1) in connection. The membrane46 lays against a plunger 49 which is connected to a mercury switch 50. A contact of the Mercury switch 50 is connected via a line 51 to one brush 43, while the other Contact is connected to the other brush 43 via a line 52. The motor 37 is on the lines 53 and 54 and a relay 55 connected to the network. A contact of the mercury switch 50 is connected to line 53 via lines 51 and 56, while the other contact is the mercury switch 50 is connected to the line 54 via the lines 52 and 57 and the winding of the relay 55 is. The in F i g. 3 works as follows: In the position shown is the Mercury switch 50 and relay 55 open. The brushes 54 are in contact with an insulating Part of the disk 41, the rotary slides 16 and 17 are located in one in FIG. 1 position shown and one filter exerts its cleaning effect while the other is being rinsed. Be it assumed that the rotary slide valve 16, 17 is in the position shown in FIG. 1 are located in the drawn position. The filtering device 2 is thus traversed by the liquid to be cleaned and gradually increasingly clogged. This creates a pressure difference between the tubes 35 and 36 the end. As a result, the diaphragm 46 bends downward and closes at a certain point Pressure value the mercury switch 50. This causes the relay 55 via the line 56, 51, the Switch 50, lines 52 and 57, relay winding 55 and the mains are attracted. This will make the Current from the power source through line 53, motor 37, line 54, the relay contacts and closed back to the power source. The motor 37 thus rotates the shaft 20 via the worm 40 and the worm wheel 39 to the rotary valve 16 and 17 from the extended position to the dashed line Position in Fig. 1 are converted. At the same time, the insulating disk 41 rotates, so that one The conductive segment 42 bridges the brushes 43 and thereby the contacts of the mercury switch 50 shorts. When the rotary valve 16 and 17 have reached their other position, the is the same Pressure in the tubes 35 and 36, whereby the membrane 46 returns to the starting position and the mercury switch 50 is opened. The plunger 49 can be connected to a spring in order to achieve this cause. The relay winding remains energized because the current from the power source is now over the line 56, the brushes 43 and the conductive segment, the lead 57, the winding 55 and back to the Power source flows. The motor 37 thus continues to rotate even when the mercury switch 50 is in its has returned open rest position until the insulating disk 41 has reached a position in which the Brushes 43 rest on the insulating space between conductive segments 42. This Gap between adjacent conductive segments is just as much wider than the brushes 43, that no short-circuit between the brushes can occur when they are on the insulating space riot. In this position, the winding of the relay 55 is energized and the relay drops out, whereby the motor 37 is disconnected from the power source and stops. The brushes 43 and the conductive Segments 42 are designed so that the motor 37, the rotary valve 16 and 17 straight from the extended Position in the dashed position in F i g. 1 and then stops. In this position the filter of the filtering device 1 exerts its cleaning effect on the one flowing in through the inlet 12 Liquid out, while the filter of the filter device 2 through the purified liquid is rinsed.

Another embodiment of a hydraulic

ίο actuated reversal is in F i g. 7 shown. The two filter devices 1 and 2 are only indicated. The filtering device 1 has inlets and outlets 3 and 4 and the filtering device 2 has inlets and outlets S and 6, each of which again consists of flanged nozzles. The fittings 7, la, 8 and 8ß are connected to the inlets and outlets 3 to 6 with flanges. In the valve 7 shut-off devices 9 and 9 α between the inlets and outlets 6 and 3 are provided. In the faucet la

ao, on the other hand, there are shut-off devices 9 & and 9 c between the same inlets and outlets. Likewise, the parallel-connected fittings 8 and 8 a with shut-off devices 10 and 10 α or 10 & 10 c are used as a connection between the inlets and outlets 4

as and 5 provided. The shut-off devices 9 and 9 b are provided with a valve spindle 58 which is connected to a piston 59 arranged in a cylinder 60. The shut-off devices 9 and 9 b have such a distance from one another that one is always closed and the other is open. The same applies to the valve pairs 9 c and 9 a, 106 and 10 and 10 c and 10 a. These are each connected via the valve spindle 58 a, 58 & and 58 c with the pistons 59 a to 59 c in the cylinders 60 a to 60 c. The outlet 11, designed as a flange tube, is connected to the fitting 7. Likewise, the inlet 12 with the fitting la, the outlet 14 with the fitting 8 and the inlet 13 with the fitting

8 a connected. A pump is switched on again between the inlet 13 and the outlet 14, the suction side of the pump being connected to the outlet 14 and the pressure side to the inlet 13. The pipes 35 and 36 connected to the fittings 8 and la are used to determine the pressure difference in the filter, which is used to clean the liquid. This pressure difference again serves as a control signal for a control device 30. Furthermore, manometer tubes 61 and 62 are provided which are connected to the inlets and outlets 4 and 5, respectively.

Two pressure lines 31 and 32 lead from the control slide 30 to the cylinders 60, the line

31 with lines 63 and 64 and the line

32 is connected to lines 65 and 66. The line 63 leads to the cylinder 60 b below the piston 59 & and to the cylinder 60 above the piston 59. The line 64 leads to the cylinder 60 c above the piston 59 c and to the cylinder 60 a below the piston 59 a. The line 65 leads to the cylinder 60 & above the piston 59 & and to the cylinder 60 below the piston 59. The line 66 leads to the cylinder 60c below the piston 59c and to the cylinder 60a above the piston 59a.

The embodiment described operates as follows: If the filter device is in the in Fig. 7 is the position shown, the valves

9 c, 9, 10 & and 10 a closed and the valves 9 a. 9 b, 10 and 10 c are open, the pressure in the cylinder

linder 60 below the piston 59 is greater than above it, the pressure below the piston 59 c is greater than the pressure above it and the same applies to the pressure above the piston 59 b and above the piston 59 a. These pressure differences in the individual cylinders are generated by the control slide 30, as will be explained in detail below. In the in F i g. 7 the position of the shut-off elements shown, the liquid to be cleaned is sucked in through the inlet 12, flows through the fitting la, the valve 9b, the inlet 6 and the filter device 2 and, after cleaning, passes into the outlet 5. From there, the pure liquid flows through the valve 10 into the fitting 8, the outlet 14, through the pump and into the inlet 13. Then it flows through the fitting 8 a, the valve 10 c, the inlet 4 and through the filter of the filter device 1. This is flushed through and the dirty liquid discharged through the outlet 3, the valve 9 a, the fitting 7 and the outlet 11. Here, too, only pure liquid can flow through the pump. If the filter of the filtering device 2 becomes clogged, there is a pressure difference between the tubes 35 and 36, which actuates the control slide 30 at a certain size, whereby the liquid pressure in the tubes 31, 63 and 64 is greater than in the lines 32, 65 and 66 will. As a result, the pistons 59 α and 59 b are raised and the pistons 59 and 59 c are lowered. In this way, the in F i g. 7 opened valves closed and the closed valves opened and the filtering devices 1 and 2 switched.

A hydraulic control device 30 which, in connection with the embodiments according to FIG. 4th and 5 or 6 and 7 can be used is shown in FIG. 8 shown.

A diaphragm valve 44 with a housing 45 which contains a diaphragm 46 serves as a sensing element. This divides the housing 45 into two chambers 47 and 48. The line 35 (see FIGS. 4 and 7) is connected to the chamber 48 and the line 36 to the chamber 47. The membrane 46 presses on a plunger 49 which is connected to a valve 67 in a cylinder 68. A compression spring 69 presses the plunger 49 upwards so that it returns to the position shown when the diaphragm 46 is not loaded. In the cylinder 68 there is a piston 69 a, which is provided with narrow through bores 70. On the inside of the bottom of the cylinder 68 there is a ring 71 which, together with the piston 69 α, forms an inner chamber 72 and an annular chamber 73. A tube 74 is connected to the chamber 72, while tubes 75 and 76 are connected to the annular chamber 73.

There is a differential regulator 77 is provided, which consists of a housing 78 with pistons 79 to 83, the are attached to a common axis 84. The pistons and the housing create five chambers 85 to 89 formed. The four pistons 79 to 83 are together with the axis 84 in the longitudinal direction Housing 78 movable. In the position of the pistons shown, the pipes 90, 91 and 92 are with them the chambers 88, 87 and 86 in communication, while the pipes 93, 94, 95 and 97 with the Chambers 89, 88, 87 and 85 are in communication. The pipes 98 and 99 are with the interior of the housing 78 connected. The pipelines 94 and 95 lead to a control slide valve 100 from a housing 101 with four pistons 102 to 105 and a common axis 106. The pistons with the Axles 106 can be moved together in the housing 101 in the longitudinal direction. In the in F i g. 8 shown Position they form with the housing 101 chambers 107 to 110. The pipeline 94 is with the chamber 110 in connection. The pipes 111, 112 and 113 are connected to the chambers 107, 108 and 109

ίο in connection, while the outlet lines 31 and 32 (see also FIGS. 6 and 7) are in communication with chambers 109 and 108, respectively. A pipeline 114 is connected to a pressure fluid source. Water or oil, for example, can be used as the hydraulic fluid to serve. If water is used, it is intended to be a lubricant for the seals, packings and gaskets moving parts included. The pipeline 114 is connected to the lines 76 and 75. The pipeline 74 is connected to the pipeline 91 and also leads via the pipelines 115 and 116 Diaphragm valves 117 and 118, the shut-off devices in the pipes 61 and 62 (see Figs. 4 and 7) open or close. The pipeline 74 is also via a needle valve 119 and a check valve 120 connected to a drain or reflux pipe 121. Also the pipes 90 and 92 are connected to the drain pipe 121 via the check valve 120. The pipeline 121 can with the Be connected to the pressure fluid source or lead the fluid to the outside, if this is not the case more should be used .. A pipe 122 leads from the diaphragm valve 117 to the two pipes 98 and 99. The pressurized fluid source is connected to the housing via pipes 114 and 112 101 of the control slide 100 connected. A pipeline connected to lines 111 and 113 124 communicates with the interior of the cylinder 68 above the piston 69 a when the Valve 67 is open.

The control member 30 can be used for all the embodiments according to FIG. 4 through 7 are used, its However, the method of operation is described below in connection with the embodiment according to FIG. 7 described. It is assumed that the pressure fluid consists of Wassej.

When the various pistons are in the position shown in FIG. 8 and valve 67 is closed, primary pressurized water from the pressurized water source passes through line 112 into chamber 108 and out through conduit 32 to lines 65 and 66 in FIG. 7 and 26 'and 29' in FIG. 6. On the other hand, line 3-1 is connected to lines 63 and 64 in FIG. 7 and 27 'and 28' in FIG. 6 is in communication, connected via the chamber 109, the lines 113 and 124 and the check valve 120 to the drain 121. In this case the pistons 59, 59b, 59c and 59a are in the position shown in Fig. 2 and four valves are open while the other four are closed. The filter of the filtering device 2 thus performs its cleaning function while the filter of the device 1 is flushed through. With increasing blockage of the filter 2, a pressure difference forms between the lines 35 and 36, the pressure in the line 35 becoming lower than in the line 36. This pressure difference appears on both sides of the membrane 46, so that at a certain size of the

609 568/365

Pressure difference, the membrane 46 bends downward and presses the plunger 49 against the spring 69 downward, the valve 67 being opened. As a result, the water located in the cylinder 68 above the piston 69 a can flow off through the valve 67, the line 124 and the check valve 120 and reaches the drain line 121.

The pressurized water also reaches the lines 75 and 76 via the line 114. Since the water pressure in the annular chamber 73 is now greater than the pressure above the piston 69 α , this piston rises, so that pressurized water from the annular chamber 73 into the chamber 72 can get. This pressurized water exits the chamber 72 through line 74 . The water pressure closes the diaphragm valves 117 and 118, whereby a valve between the lines 61 and 122 or 62 and 123 is closed and the pistons of the diflerential regulator 77 in the position shown in FIG. 8 position shown. The pressurized water continues through the line 91, the chamber 87 and the line 95 to the control slide 100 and presses from the right on the piston 102, whereby the pistons 102 to 105 are displaced to the left. The water in chambers 110 and 107 flows through duct 94, chamber 88, line 90, check valve 120 and drain line 121 or lines 111, 124, check valve 120 and drain line 121 . When the spool pistons are in the left position, pressurized water is supplied via line 112 to line 31 through the chamber defined between pistons 104 and 103 and housing 101 . The line 31 is, as I said, connected to the lines 63 and 64 (Fig. 7), which is why these lines come under pressure and raise the pistons 59 a and 59 b , while the pistons 59 c and 59 are lowered in their cylinders, so that the in F i g. 7 valves shown open now close while the valves shown closed open. The water is discharged from the various cylinders via lines 65, 66 and 32. From the line 32 the water passes through the chamber located between the pistons 104 and 105 into the lines 111 and 124 and then via the check valve 120 to the drain line 121. In this way, the liquid flowing into the inlet is deflected so that the filter 1 the liquid begins to clean while the filter 2 is flushed through. This change is fully automatic. During the change, the pressure in the tubes 35 and 36 is equalized and the membrane 46 returns to the position shown in FIG. 8, the plunger 49 returning to its rest position by the spring 69 and the valve 67 closing. After the valve 67 is closed, the pressure above the piston 69 a is equal to the pressure below this piston, since pressure equalization is provided through the channels 70. Because the upper surface of the piston 69a is larger than the lower surface, the piston 69a moves downward into the position shown in FIG. 8 and separates the annular chamber 73 from the chamber 72. The pressure in the chamber 72 and in the line 74 slowly decreases through the needle valve 119 until the diaphragm valves 117 and 118 open, whereby the lines 61 and 122 and 62, respectively and 123 are connected to each other. Since the line 61 is connected to the pressure side of the pump located between the inlet 13 and the outlet 14, but the line 62 is connected to the suction side of this pump, the pressure in the line 61 is now greater than in the line 62. This pressure difference becomes communicated to differential regulator 77 through lines 61, 122, 98, 99, 62, 123, 97 and 93, causing the pistons of pressure regulator 77 to move to the right, with the water in chambers 98 and 85 being discharged through lines 93 and 97 will. When the filter has been changed, the pistons of the control slide 100 are in the left position, while the pistons of the differential regulator 77 are in the right position. In this position line 91 is connected to line 94 , but no pressurized water flows through it and the assembly is ready for the next replacement. This next exchange takes place in such a way that the pistons in the control slide 100 to the right in FIG. 8 are moved, whereby the pressure gauge reaches the line 32 and the pistons 59 to 59 c in the in F i g. 7 resets, while finally the pistons of the differential regulator 77 into the position shown in FIG. 8 return to the position shown.

If the described control device 30 in connection with the in F i g. 6 is used, it operates in exactly the same way and causes the rotor 24 to rotate from the extended position to the dashed position, whereby the functions of the filtering device 1 and 2 are automatically reversed.

For the subjects of the subclaims, protection is only given in connection with claim 1 strived for.

Claims (7)

Patent claims: 1. Filtration device, in particular for ship drainage systems, consisting of two filters arranged next to one another with shut-off devices in between, which enable the two filters to be connected in series in opposite flow directions for the purpose of rinsing one filter each with the help of a pump, characterized in that the two shut-off devices (9 and 10) in the connecting lines (7, 8) between corresponding filter connections (3, 6; 4, 5) each have their own inlet nozzle (12, 13) and their own drain nozzle (11, 14) such that the connection of one of the at ? the associated filter connections with the inlet and the other with the outlet is possible, so that between the outlet (14) of the clear filtrate and its re-entry (13) into the filter to be backwashed, the pump (15), through which clear liquid always flows in the same direction, is switched on. 2. Filtration device according to claim 1, characterized by a control element (30, 37) which, when a certain pressure difference occurs between the dirty liquid inlet (12) and the clear filtrate outlet (14), the shut-off elements (9, 10) automatically move from one position to the other surrounds. 3. Filtration device according to claim 2, characterized in that the control member consists of an electric motor (37) whose power is supplied at a certain pressure difference is switched on and which switches itself off when the shut-off devices are switched. 4. Filtration device according to claim 3, characterized by a switch (50) which is at a certain pressure difference between two at the dirty liquid inlet (12) and the clear filtrate drain (14) connected pressure gauge lines (35, 36) is closed and A relay (55) connects the motor (37) to the mains, as well as one from the motor driven insulating disk (21) carrying conductive segments (42) shaped in such a way that two Brushes (43) lying parallel to switch (50) are bridged until the shut-off devices and so that the insulating disk has reached the new position. 5. Filtration device according to claim 2, characterized in that the control member consists of a piston valve (30) which adjusts the shut-off elements as a function of IO causes a certain pressure difference by means of hydraulically operated pistons (24, 59). 6. Filtration device according to claim 3 or 5, characterized in that the shut-off elements are designed as four-way cocks (16, 17), which by means of a shaft actuated by the control element (20) are interconnected. 7. Filtering device according to claim 1 or 2, characterized in that each shut-off element consists of two double valves (10, 10 b, 10 a, 10 c) which are alternately closed and open. Considered publications:
German Patent Nos. 258 509, 294 312, 675493, 715663; Patent specification No. 12257 of the Office for Invention and Patents in the Soviet Zone of Occupation Germany; U.S. Patent Nos. 2,679,936, 2,854,140. For this purpose 2 sheets of drawings 609 568/365 5.66 © Bundesdruckerei Berlin