Filter cartridge for water treatment system

[0001] The present invention relates to water purification systems, and in particular to such systems which have an airtight manifold head and a reverse osmosis cartridge and one or more filter cartridges.

BACKGROUND OF THE INVENTION [0002] Reverse osmosis systems are known. The main component of such a system is a semi-permeable membrane through which raw water is passed. Such systems typically include an additional carbon filter or ceramic filter that removes impurities either before passing through the indicated membrane or after passing through. Such systems are often installed for domestic purposes.

[0003] Prior art solutions include electronics that detect when a reverse osmosis membrane needs to be replaced. Typical prior art systems include measuring the specific conductivity of the water entering the reverse osmosis cartridge, and then measuring the specific conductivity of the water at the outlet of the reverse osmosis cartridge. The conductivity of water is proportional to the total amount of solids dissolved in it. The ratio of the aforementioned conductivity value will be an indication as to the effectiveness of retention of impurities on the reverse osmosis membrane.

[0004] The prior art systems also include applications where a purified water pump is installed in the factory installation. The purified water pump ensures greater system efficiency. The purified water pump increases the net pressure on the reverse osmosis membrane by isolating the pressure on the membrane from the pressure of the obtained purified water, thereby reducing the back pressure of the filtrate.

[0005] The prior art also includes systems that solve the problem of limiting fluid leakage that occurs when replacing cartridges.

SUMMARY OF THE INVENTION [0006] The object of the present invention is to provide an improved locking mechanism of the filter cartridge and the manifold head.

[0007] A further object of the present invention is to provide an improved method for monitoring the operation of a reverse osmosis membrane in a drinking water supply system.

[0008] A further object of the present invention is to provide a system with a modular branch head.

[0009] The object of the present invention is to provide a system for retrofitting a reverse osmosis filter system that includes the use of a purified water pump.

[0010] The object of the present invention is to provide a cartridge with a reduced inlet opening to reduce leakage when replacing the cartridge.

BRIEF DESCRIPTION OF THE DRAWINGS [0011]

Fig. 1 is a perspective view of a water purification system with a reverse osmosis cartridge and with two filter cartridges.

Fig. 2 is a perspective view of the filter cartridge shown in Fig. 1.

Fig. 3 is a top view of the filter cartridge shown in Fig. 2.

Fig. 4 is an exploded view of the filter cartridge shown in Fig. 2.

Fig. 5 is a perspective view of the manifold head connected to the water purification system shown in Fig. 1 from below.

Fig. 6 is a block diagram of a reverse osmosis membrane monitoring system.

Fig. 7 is a flow diagram of the purification process for the system shown in Fig. 6.

Fig. 8 is a perspective view of the system with a modular manifold head.

Fig. 9 is a perspective view of the modular manifold head from above.

Fig. 10 schematically illustrates the layout of a reverse osmosis water purification system with a purified water pump.

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Fig. 11 is a cross-sectional view of the modular manifold and cartridges shown in Fig. 1.

Fig. 12 is a perspective view of the modular manifold from above using a purified water pump.

DETAILED DESCRIPTION OF THE INVENTION [0012]

Figure 1 shows an embodiment of a water purification system 10 according to the present invention. This system includes a manifold head 12, (compare Figure 5) first filter cartridge 14, reverse osmosis cartridge 16 and second filter cartridge 14. Also shown is the manifold cover 20.

Figure 2 shows a filter cartridge 14 according to the present invention. This filter insert 14 includes a housing 22 having an outer annular flange 24 with a double guide thread 26. Also shown is an inner annular flange 28 which includes an O-ring 30 that provides sealing. Also shown is a fitting 32 passing through the annular flange 28.

Figure 3 is a top view of the filter cartridge 14 and shows the cylindrical wall 34 of said inner annular flange 28 as well as the longitudinally extending slat 36.

Figure 4 is an exploded view of said filter cartridge 14 to more accurately show this longitudinally extending slat 36. It can be seen that this longitudinally extending slat 36 includes a leading end 38.

Figure 5 illustrates a manifold head 12 having a connector 40 for a filter cartridge. This filter cartridge 40 includes a threaded outer annular collar 42 and an inner annular collar 44. This inner annular collar 44 has an annular projection 46 and four longitudinal slots 48. These longitudinal slots 48 are equidistant from each other.

[0013] It will be appreciated that when said filter insert 14 is screwed onto the connector 40 to achieve a fully secured position, this filter insert 14 assumes its final position with longitudinally extending slats 36 inserted into the respective slot 48.

[0014] Figure 6 is a block diagram of a system 50 for monitoring the operation of a reverse osmosis membrane. This system 50 includes a microcontroller 52 with a memory 54 in which the program is installed. System 50 includes a single probe set 58 downstream of the reverse osmosis membrane down the water stream. The probe kit 58 includes a reference resistor 60 and a thermal resistor 62 (thermistor). Said microcontroller 52 is coupled to a signaling LED 64, which signals the need to replace the reverse osmosis cartridge. This microcontroller 52 is also coupled to an LED 66 signaling the operation of the system, while the power button 68 is pressed, also coupled to this microcontroller 52. Also a water flow sensor is connected to microcontroller 52.

[0015] Figure 7 is a block diagram 72 covering operations performed by a program installed in memory 54.

[0016] Step 74 refers to initiating a recalibration procedure. Re-calibration is initiated after replacing the reverse osmosis (RO) membrane and turning on the power. During step 76, the system measures the water flow through the system. During step 78, the system means or detects a flow of 15 gallons (about 57 liters) of water through the system. During step 80, the system measures the initial water conductivity after passing through the membrane to reverse osmosis. In one embodiment, during step 80, this initial value of purified water conductivity is based on averaging about 10-50 measurements of water conductivity. During step 82, the value of the specific conductivity of the resulting, purified water or average specific conductivity is assumed to correspond to 90% rejection of impurities. Then, at step 82, a threshold value is calculated indicating the need to replace the membrane, corresponding to 75% rejection of the impurities. During step 84, this threshold value is maintained indicating that the membrane needs to be replaced. Step 86 is to routinely measure the conductivity value of the resulting purified water. Step 88 consists of averaging the previous 20 measurements of the water conductivity. During step 90, it is determined whether the average of step 88 is below the threshold indicating the need to replace the membrane of step 84. For the average below the threshold mentioned, the system proceeds to step 92, which causes

EP 2 189 208 B1 inclusion of a signaling LED indicator signaling the need to replace the reverse osmosis (RO) membrane.

[0017] Figure 8 illustrates an embodiment of a modular water purification system 94. The water purification system 94 shown in Figure 8 includes a modular manifold head 96, a manifold cover 98, a first filter cartridge 100, a reverse osmosis cartridge 102, and a second filter cartridge 100. A further manifold head 104 and cover 106, as well as an insert 108, are also shown as an additional unit. The system according to the drawing 8 provides a modular system in which additional modular manifolds 104, 106, 108 can be connected to the water purification system 94 through a connector 110. This connector 110 has a plurality of branches 112 extending from the flat body 114. Each branch 112 has a slot 116 and a bevelled edge guide 118. This connector 110 also has a tubular portion 120 extending through the flat body 114. This tubular portion 120 has an opening 122 extending through the entire tubular portion 120.

[0018] Each manifold 12, 96, 104 has an end wall 124 having four holes 126.

[0019] Figure 9 is a perspective view of the manifold head 12 having two end walls 124 each having four holes 126. These holes 126 are arranged in pairs, one above the other. For example, lower hole 126 and upper hole 126 form one pair. Each pair of holes 126 has a pair of vertical walls 130 spaced apart and facing each other. These vertical walls 130 are shown extending from the inner surface 132 of the end wall 124 and the bottom surface 134 of the manifold head 12. Flange 136 extends from said inner surface 132 of the end wall 124 toward the interior of the manifold head compartment 12. Said flange 136 includes an upper ramp 138 and bottom ramp 140. Said collar 136 has a front edge 142 and a first and second side edge 144, 146. This front edge 142 is generally parallel to said end wall 124. This first side edge 144 and second side edge 146 form said upper ramp and lower ramp 138, 140. This upper ramp

138 and the lower ramp 140 differ from each other in the direction of inclination from said inner surface 132 towards the interior of the manifold head compartment 12. One of the four flanges 136 is shown by the dashed line in Figure 9.

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Said ramps 138, 140 have a proximal end 148 and a distal end 150. This proximal end 148 is slightly offset from the edge of the hole 126. This distal end 150 is offset in collision with respect to the position of the hole 126. Figure 9A shows additional details.

[0020] Referring to Fig. 8, it should be seen that when the connector 110 is inserted into the holes 126 of the manifold head 96 on the right side of the drawing, the beveled edge 118 of each of the spring branches 112 will be deflected by the respective ramp 138, 140. When the connector 110 is fully inserted through the four holes 126, the gap 116 will widen behind the distal end 150 and both pairs of branches will snap behind the respective distal ends 150 as a result of the entry of the edge of the gap 116 into the latching arrangement with the distal end 150 ramps 138, 140. W at this time, the tubular portion 120 will engage the tubular connector 152 to form a hermetic joint. The additional modular manifold 104 will be connected in a similar manner.

[0021] Figure 10 is a diagram of a water purification system 160 in which a cover with an automatic shut-off valve 162 (compare Figure 5 and

9) can be removed and replaced with another cover 164 adapted for using a purified water pump. Figure 11 shows a cross section through a water purification system that includes a modular manifold 12, a first cartridge 14, a reverse osmosis cartridge 16, and a second filter cartridge 14. Said manifold 12 is shown to include a connector 166 for receiving a corresponding cartridge connector 168 16 for reverse osmosis. Said manifold 12 includes a first manifold access port 170 for coupling to the outlet of the reverse osmosis cartridge 16, a second manifold access port 172 coupled to the outlet from the reverse osmosis stage. Cover 162 - a variant without a purified water pump, is adapted to hermetically close said first and second access ports 170, 172 in a variant without using a purified water pump. Cover 164 - a variant with a purified water pump is also adapted to hermetically close the aforementioned: first and second, access ports 170, 172 and includes a port 174 receiving from the purified water pump, which receives a pipe connector 175. The cover 164 of the variant with a purified water pump includes first and second access ports 176, 178 and a flow channel 180 in communication with said first and second access ports as well as said receiving port 174 from the purified water pump. Team

The shut-off valve is located in said first access port 176 for coupling to the outlet of said reverse osmosis cartridge 16. This second cover 164 includes a substantially flat body portion 184 that has first and second ends defined. Mounting holes 186 are provided to secure this cover to said manifold.

[0022] Said manifold head has a bottom part 188 of the membrane socket, with the top part open. Said second cover 164 has an upper membrane seat portion 190 for connecting to said open upper portion and forming a membrane chamber that receives the membrane. Said upper membrane seat 190 includes an opening 192 for fluid communication with fluid channel 180. Said manifold includes a flow channel coupled to an outlet port from the pre-filtration stage and an inlet port to the reverse osmosis stage, wherein said flow channel provides fluid communication with said bottom portion 188 of the membrane seat of said manifold. It should be noted that the current water purification system can be installed at the factory with a cover 162 for the variant without the purified water pump, in which a plug 194 is provided at the outlet port 174 of the purified water pump. A kit can be provided for upgrading existing systems by removing said first cover 162 and replacing it with said second cover 164, which has said tubular connection 175. Then a quarter inch conduit 196 can be connected to this pipe coupling 175 and led out through a through hole 198 shown in Fig.

12. This conduit 196 extends down to the purified water pump 200 shown in Fig. 10. This purified water pump 200 has a purified water outlet 202 equipped with a conduit 204 leading to T-coupling 206. This T-coupling 206 has a distal conduit 208 connected to the storage tank 210, as well as a conduit 212 connected again to said manifold. The brine side (water with impurities) of said purified water pump has a brine supply line 214 from the drain outlet 216 of the manifold head and a brine discharge line 218 connected to the drain outlet. For a full picture, the power cord 220 and wire 222 leading to the tap are also visible.

[0023] The installation kit comprises at least the aforementioned second cover 164, and may further include an exchange shut-off valve as well as an exchange: O rings, pipes, fasteners and installation instructions.

[0024] Fig. 11 also shows said filter insert 14 having a reduced opening in said connector 32 to minimize flow when changing the filter insert. The new features of this filter cartridge are explained below.

However, it will be clear that these features can also be included in the reverse osmosis cartridge.

[0025] Said filter cartridge 14 includes an outer housing 22 of the cartridge having a cylindrical portion with an upper portion and a lower portion. The said lower part is blinded. Said upper portion has an arm 250 with a generally cylindrical neck portion 252 extending upward from the arm 250. The cylindrical neck portion 252 forms part of the connector. This cylindrical neck portion 252 has a cylindrical opening having a cylindrical wall of this opening defining a first diameter. This cylindrical bore wall includes a circular ring 254 protruding from this wall and defining a second diameter that is smaller than said first diameter. The inner housing 256 of the cartridge includes the upper part with the arm 258, the tubular part

260 extending upward from the inner arm 258 and a tubular portion 260 defining the outlet opening. This tubular portion 260 defines an outer diameter being a third diameter, wherein the third diameter is smaller than said first and second diameter. This tubular portion 260 and the circular ring 254 define a cartridge inlet that is a circular gap. It should be noted that this annular gap is minimized due to the current design and thereby reduces the likelihood of leakage. Said manifold is adapted to be compatible with said filter cartridge 14. In particular, said manifold includes a connector

40, which has an inner annular flange of such a defined length that when the insert 14 is connected to this manifold head, said inner flange extends around said tubular portion 260 and upwards to said round ring with a minimum tolerance gap.

[0026] According to the present invention, a cartridge 14 is therefore proposed which has a reduced inlet opening to reduce leakage when replacing the cartridge.

[0027] Therefore, according to the present invention, a locking mechanism of a hermetic manifold head and insert is also proposed, which locking mechanism comprises a hermetic manifold head 12 equipped with a connector 40, which connector 40 has a threaded outer ring flange 42 and an inner ring collar wherein the inner annular collar 44 has an annular projection 46 and at least one elongated slot 48 extending from the projection 46 along a portion of said annular collar 44; and a cartridge (14) having a connector 32, which connector 32 has a threaded outer annular flange 24 for connection to said threaded outer annular flange 42 of the manifold head 12, the connector 32 of the insert 14 also having a cylindrical wall 34 located within the threaded outer the collar 24 of the insert 14, which cylindrical wall 34 has at least one longitudinally extending slat 36 which receives the corresponding said slot 48 when said insert 14 is threaded attached to said manifold to a fully securing position.

[0028] According to a particular embodiment, this longitudinally extending slat 36 comes into contact with said annular projection 46 approximately 1/8 turn before reaching a fully securing position.

[0029] According to a particular embodiment, the manifold head 12 comprises four elongated slots 48 extending from the projection 46 along parts of said annular flange 44 and evenly distributed circumferentially around said annular flange 44, said insert 14 including four longitudinally extending slats 36, extending along said cylindrical wall 34, which four longitudinally extending slats 36 are evenly distributed circumferentially around said cylindrical wall 34, each of these longitudinally extending slats 36 being adapted to receive it through a respective slot 48 in said insert 14 in a fully securing position.

[0030] Accordingly, a modular system for assembling manifold water filter heads is also proposed according to the present invention, which system includes (as shown in Figures 8-9A):

first and second branch heads 96, 104, each branch head having a first side 124 and a branch head chamber, which first side 124 includes a pair of ramps 138, 140, and each ramp has a first end and a second end, with ramp edge 144, 146 defined between said first end and the second end, said pair of ramps being arranged in an opposite and outward arrangement, with said first ends 148 near said first side 124 and with said second ends 150 offset from said first side 124 to the center of the chamber of said manifold head, where the first ends 148 of this pair of ramps 138, 140 define the distance D1, and the second ends 150 of this pairs of ramps 138, 140 define the distance D3 and distance D3 is greater than the distance D1, and each pair of said ramps 138, 140 defines at said second end 150, locking edge extending in the divergent direction; and a connector 110 having a body 114, a first pair of branches 112 extending from the body 114 generally in the first direction and a second pair of branches 112 extending from the body 114 generally in the opposite direction, each pair of branches 112 having a latch 117 at the distal end, and each pair of pawls 117 defines the distance D2, where D1 is less than or equal to D2, which is less than or equal to D3.

[0031] According to the present invention, therefore, it is also proposed in accordance with the present invention an installation kit for replacing the cover with an automatic shut-off valve, previously installed on the manifold head of the water purification system, said manifold head comprising a first access port adapted to be coupled to the reverse osmosis cartridge, a second port access coupled to the outlet from the reverse osmosis stage, which kit includes (as illustrated in Figure 10-11):

a cover 164 having a first access port 170 of this cover, a second access port 172 of this cover, and having a receiving port 174 from a purified water pump with a tubular connector 175 enabling the use of a purified water pump.

[0032] According to a particular embodiment, the installation kit additionally comprises a control valve assembly adapted to receive through the first access port 170 of said cover.

[0033] According to a particular embodiment, said cover includes a substantially flat body portion having a fluid channel that extends longitudinally within this flat body portion, where one end of this body portion includes a purified water pump outlet port with a tubular connector, the other port access of this cover adjacent to said tubular connector, and the first access port of this cover is adjacent to the second access port on the opposite side from the tubular connector.

[0034] According to a particular embodiment, said installation kit additionally comprises O rings for exchange to the first and second access ports 176, 178 of said cover.

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