WO1986006612A1

WO1986006612A1 - Device for the degasing of disinfected water in a disinfection plant of a dental surgery

Info

Publication number: WO1986006612A1
Application number: PCT/DE1986/000172
Authority: WO
Inventors: Konstantin Ledjeff
Original assignee: Fraunhofer-Gesellschaft Zur Förderung Der Angewand
Priority date: 1985-05-09
Filing date: 1986-04-23
Publication date: 1986-11-20
Also published as: EP0221094A1; DK8587D0; DK8587A; JPS62502810A; DE3516618C1

Abstract

The water disinfection plant of a disinfected water degasing unit in a dental surgery for the dental instruments and other water uses, arranged in the patient's chair, is connected by a supply conduit (1) and by means of valves (28, 29) with the input lines (32, 33) of two closed tanks (8, 9). The tanks (8, 9) are connected by means of discharge lines (34, 35) and by means of a valve (36) to a supply conduit (22) leading to the user. In one of the two positions of the valves (28, 29), the inlet conduits (32, 33) have the function of a suction line, connected by a conduit (26) to a vacuum apparatus. The valves (28, 29) are operated so that the tanks (8, 9) are alternatingly communicated with the vacuum apparatus or with the supply conduit (1) and the supply line (22). While a degasing operation is taking place in one of the tanks (8, 9), the other tank (8, 9) is emptied of degased water and is filled with water coming through the supply conduit (1).

Description

Device for degassing the in a

A dental water purification equipment

Treatment device sterilized water

The invention relates to a device for degassing the water disinfected in a water sterilization system of a dental treatment device for the dental treatment instruments and the other water consumers assigned to a dental patient chair.

In dentistry, patient chairs with a preferably built-in water disinfection system are used for dental treatment, which supplies germ-free water for a number of instruments, such as turbine instruments, handpieces, contra-angle handpieces and surgical instruments. In addition, the usual dental equipment requires water for a fountain system and a syringe for water. Disinfection methods using chemical or electrical means are known for disinfecting the tap water that is normally used. In particular, DE-OS 23 11 504 discloses a device in which water is disinfected in an anodic oxidation chamber. The gases generated in such disinfection systems are undesirable because, on the one hand, they lead to disruptions and impairments in the dental workflow, in particular in the coolant system of a dental device, and, on the other hand, they contain dangerous gases, such as detonating gas. To avoid the formation of the undesired gases, the cathode of the anodic oxidation chamber in the device known from DE-OS 23 11 504 is surrounded by a diaphragm made of a porous ceramic material, the diaphragm being filled with concentrated alkali metal chloride solution. The invention has for its object to provide a device for degassing, which allows the gas which leaves the water disinfection system of a dental treatment device and contains dissolved gas components to be degassed in a simple manner, regardless of the type of gas, without the outlet side - to change the operating pressure.

This object is achieved according to the invention in that the water disinfection system is connected via a supply line and a first controllable valve arrangement to the inlet lines of at least two closed containers, which via outlet lines and via a second valve arrangement to a consumer line leading to the water consumers and are connected to a vacuum generator via suction lines opening into the container and that the valves can be actuated by a control circuit so that the containers are alternately connected to the vacuum generator or to the supply line and the consumer line.

Due to the fact that two closed, sufficiently pressure-resistant containers which can be acted upon by vacuum are provided, the device permits vacuum degassing, the operating pressure being built up again after switching over by flowing water in the respective container. While vacuum degassing takes place in one container, the water degassed in a previous cycle of the other container is switched to the consumer line, the volume of the sterilized and degassed water flowing off being followed by sterilized and not yet flowing degassed water is filled. The degassed mixes with the non-degassed water, whereby the degree of degassing that was originally achieved deteriorates again in part, but this deterioration is limited and can be adapted to the respective requirements by selecting the cycle times, the volume ratios and water throughputs.

The valve arrangements can consist of simple electromagnetically controllable shut-off valves or of 3/2-way valves. In a particularly advantageous exemplary embodiment, the input lines and the suction lines of each of the two containers are realized by common lines which are connected to the always effective main connection of 3/2-way valves, the alternatingly effective changeover connections of the supply line and a common vacuum line are connected in opposite directions so that the first suction line connected to the vacuum line is connected to the idle changeover connection of one valve and the second suction line connected to the vacuum line is connected to the changeover connection of the other valve, which is effective in the electromagnetic excitation of the valve . Accordingly, the supply line is divided over two feed lines, which create a connection to the containers in alternative states of the valve control.

Expedient developments and refinements of the invention are the subject of dependent claims.

The invention is explained in more detail below on the basis of the exemplary embodiments shown in the drawing. Show it: 1 is a block diagram of a device according to the invention with check valves,

2 shows a device according to the invention with 3/2-way valves in a representation corresponding to FIG. 1,

3 shows the block diagram of a device according to the invention with 3/2-way valves and containers in which the water supply and the

Extraction takes place via common lines,

Fig. 4 is a block diagram illustrating the

Connection of a vacuum generator to the common one via a liquid separator

Vacuum line of the degassing device according to the invention,

5 shows a representation corresponding to FIG. 4, but in which the sequence of the liquid separator and the vacuum generator are interchanged, _v

6 shows an arrangement essentially corresponding to FIG. 4, in which a catalyst is switched on between the liquid separator and the vacuum generator,

FIG. 7 shows an arrangement essentially corresponding to FIG. 5, in which a catalyst is connected downstream of the liquid separator according to the embodiment according to FIG. 6 and 8 shows a schematic illustration of an arrangement in which the water leaving the water disinfection system is divided into two partial streams, the first of which degasses in a degassing device according to the invention and the second degasses in a differently effective degassing tank becomes.

A first exemplary embodiment of a degassing device that can be connected to a water decontamination system is shown schematically in FIG. 1. The gas-laden, pressurized liquid coming from the water sterilization system flows into the degassing device via a feed line 1 and is first divided into a first feed line 2 and a second feed line 3. These are connected to containers 8, 9 via a first electromagnetic shut-off valve 4 and a second electromagnetic shut-off valve 5 and via a first inlet line 6 and a second inlet line 7. The containers 8, 9 are vacuum-sealed, closed, pressure-resistant containers, the volume of which is, for example, 250 cm ³ . The water entering the containers 8, 9 can leave them via a first outlet line 10 and a second outlet line 11 when the respectively assigned first outlet valve 12 or second outlet valve 13 is open.

At the highest point in the interior of the containers 8, 9 are the mouths of a first suction line 14 and a second suction line 15, each of which has a first vacuum valve 16 and a second vacuum valve 17 as well as a first vacuum line 18 and one second vacuum line 19 are connected to a vacuum generator (not shown in FIG. 1), for example a diaphragm pump, a water jet pump or the like. For the containers 8, 9, all geometries with a clearly highest point are favorable, such as, for example, conical or pyramid-shaped container lids, crooked cylinders, rotated cubes, etc. The liquid supply via the inlet lines 6, 7 is conveniently located in the upper half of the container during the drain via the output lines 10, 11 in the lower half. These are particularly favorable arrangements, but can be deviated from.

In the position shown in FIG. 1, the second vacuum valve 17 is closed, while the water can leave the container 9 through the opened second outlet valve 13. The outlet of the second outlet valve 13 is connected via a branch line 21 to a consumer line 22, which leads the degassed water to the consumers of the dental device. The water leaving the container 9 is replaced by water which flows in via the supply line 1, the second feed line 3, the second shut-off valve 5 and the second inlet line 7. In this case, the water which has not yet been degassed and which flows in mixes with the water which is already in the container 9 and which has already been degassed.

No water flows through the first feed line 2 in the position of the electromagnetic shut-off valve 4 shown in FIG. 1, since this is closed. The first output valve 12, which is connected to the consumer line 22 via a branch line 20 corresponding to the branch line 21, is also closed. However, since the first vacuum valve 16 in the Open position, the vacuum generator, not shown in Fig. 1 is effective and generates a negative pressure in the container 8, which allows vacuum degassing of the water in the container 8 which is closed on all sides. If the vacuum applied via the first vacuum valve 16 was effective for a predetermined degassing time, which depends on the gas loading of the water, the tank size, the vacuum power and the desired degassing rate, all valves 4, 5, 12, 13, 16 and 17 switched to the position not shown in FIG. 1. This is done with the aid of a control circuit, not shown in the drawing, which is connected to the valve magnet. The switching times and thus the respective cycle times are specified via clock generators of the control circuit, not shown.

After the switchover, water flows from the feed line 1 via the first feed line 2, the first electromagnetic shut-off valve 4 and the first inlet line 6 into the container 8, where the water mixes with the previously degassed water. The water leaves the container 8 via the first outlet line 10, the first outlet valve 12, the branch line 20 and the main line 22. As mentioned, the degassed water mixes slightly with the gas-laden water flowing in the container 8. This gas loading which occurs with the mixing can, however, be reduced to the desired degree, for example, by large container volumes, low flows and long cycle times. In another embodiment of the invention, only 3 pieces of 3/2-way valves are used instead of six 2/2-way valves. The assigned structure is shown schematically in FIG. 2. The supply line 1 is connected via a 3/2-way valve 23 to the input lines 6, 7, so that, depending on the position of the water-side 3/2-way valve 23, the supply line 1 either with the first container 8 or connected to the second container 9.

With a 3/2-way valve 24 on the vacuum side, either the first suction line 14 or the second suction line 15 is connected to a common vacuum line 26, which is connected to the vacuum generator (also not shown in FIG. 2). An outlet-side 3/2-way valve 25 likewise replaces two shut-off valves according to FIG. 1 and permits switching between the first outlet line 10 and the second outlet line 11 to the consumer line 22. The operation takes place in such a way that all valves 23, 24, 25 switch simultaneously.

A preferred embodiment of the invention is shown in FIG. 3. The feed line 1 is connected to a first 3/2-way valve 28 via the first feed line 2 and to a second 3/2-way valve 29 via a second feed line 3. The two 3/2-way valves 28, 29 are further connected via a first suction line 30 and a second suction line 31 and a common vacuum line 26 to the vacuum generator, which is also not shown in FIG. 3. As can be seen in the drawing, the 3/2-way valves 28, 29 are also with the containers 8 and 9 via a first common line 32 and a second common line 33 in connection.

The arrangement is such that switching the first 3/2-way valve 28 allows the container 8 to be optionally connected to the supply line 1 or the common vacuum line 26. In a corresponding manner, switching the second 3/2-way valve 29 allows the container 9 to be connected to the supply line 1 or the common vacuum line 26. In the case of the 3/2-way valves 23 and 24 of the arrangement shown in FIG. 2, instead of a switchover between water and vacuum, there was a switchover between the first container 8 and the second container 9.

Switching between the two containers 8 and 9 is, however, achieved by the third 3/2-way valve 36 connected to the first output line 34 and the second output line 35, the output of which is connected to the consumer line 22.

In the valve positions shown in Fig. 3, the water flows from the supply line 1 via the branch provided with the second 3/2-way valve 29 into the container 9, while the water in the container 8 via the first 3/2-way -Valve 28 containing branch is degassed. After a predetermined time interval, the 3/2-way valves 28, 29 and 36 switch over, the mode of operation of the two branches or lines being interchanged. When all 3/2-way valves 28, 29 and 36 are switched at the same time, however, the problem arises that the line pressure required after the switchover is not immediately available in the branch or line which was degassed before the switchover stands because time is required to build up pressure. 3, this problem can be solved by switching the first 3/2-way valve 28 a short time, for example 5 seconds, before the cycle time has elapsed, and only after the cycle time has elapsed is 1 min, for example, the switching of the 3/2-way valves 29 and 36 takes place. In this way, sufficient time is available to build up a pressure in the container 8, which is then immediately present in the consumer line 22 after the cycle time has expired.

To improve the kinetics of the degassing, it is expedient to move the liquid to be degassed. This can be done, for example, by installing stirrers (not shown in the drawing) in the containers 8, 9, by mechanical movement of the containers 8, 9 or by installing ultrasonic vibrators. A particularly simple mechanical excitation of the container contents results when the 3/2-way valve 28 or 29 in the branch or line that is degassed during the cycle time is short, ie back and forth in the range of milliseconds The water jet that shoots into the container 8 or 9 ensures good whirling and rapid degassing. Such pulses can be repeated several times. A further improvement in the degassing results from the installation of a heater (not shown in FIG. 3), which ensures thermal convection and thus facilitates degassing. The above-described arrangements for degassing water in a dental device prevent gases in the liquid lines from interfering with various functions. Although various gases are dissolved in normal tap water, particular difficulties arise when using systems for disinfection, since these often load the water with gas. An example of this are disinfection plants with hydrogen peroxide, in which oxygen is produced, or disinfection plants, which use anodic oxidation, in which oxygen and hydrogen are produced.

FIG. 4 shows an arrangement for using the degassing device provided with the reference numeral 38. After flowing through a disinfection device 37, the water enters the degassing device 38, which is constructed in accordance with FIGS. 1 to 3. The vacuum which is connected to the vacuum line 26 can be generated directly by a vacuum pump (air pump, water jet pump, membrane pump etc.) which is assigned to the degassing device 38. It is also possible to connect the vacuum line 26 to a suction line present in the dental device.

Since water is sucked in during the degassing, a liquid-gas separation is required, which can be done by inserting a liquid separator 40 between the degassing device 38 and the vacuum generator 41 shown in FIG. 4, the vacuum line 26 for the gas Liquid mixture is provided, while a liquid line 44 carries only liquid and a connecting line 42 only gas. The gas leaves the vacuum generator 41 through an outlet line 43. In the case of vacuum generators 41, which can also pump off liquid-gas mixtures, for example water jet pumps, the liquid separator 40 can also only be installed at the pump outlet, as shown in FIG. 5. The degassing device 38 is connected to the vacuum generator 41 via the vacuum line 26. The pressure side of the vacuum generator 41 is connected via a pressure line 46 to the liquid separator 40, which removes the liquid via the liquid line 44 and the gas via the line 42.

The degassing device 38 according to the invention can also be used only for a partial flow of the total sterilized liquid, the remaining water flow being degassed with another device or not at all. In the case of dental devices, the functioning of the instruments, such as the turbine instruments, the handpieces, the angle pieces or the surgical instruments, is impaired by the gases. It may therefore be advantageous to degas only the partial flow for these instruments with the degassing device 38 according to the invention. In terms of the volume requirement of the containers 8, 9, the degassing of smaller partial flows is namely favorable, since larger liquid volume flows tend to make larger containers 8 and 9 necessary.

Additional precautions must be taken if the gases generated during disinfection have to be destroyed for safety reasons. This applies, for example, to the oxyhydrogen gas generated during anodic oxidation, which consists of hydrogen and oxygen and can be converted to water at catalyst contacts. The gas mixture occurs in the vacuum degassing in the containers 8 and 9 and is then sucked off via the vacuum lines 18, 19, 26 to the vacuum generator 41. In these vacuum lines 18, 19, 26, catalysts can be installed, which for example consist of noble metal on a carrier material in the form of disks, balls, etc. The catalysts can be heated if necessary.

If there is only one line leading to the vacuum generator 41, as in the exemplary embodiments according to FIGS. 2 and 3, then a catalytic converter is sufficient. It is then expedient if a catalyst 48 is introduced into the connecting line 42 already mentioned in connection with FIG. 4, which connects the liquid separator 40 to the vacuum generator 41. 6 shows such a structure. The liquid separator 40 can be combined with the catalyst 48 in a single housing.

FIG. 7 shows how the catalytic converter 48 is arranged behind the outlet of the vacuum generator 41. The liquid separator 40 is connected to the catalyst by the connecting line 42 and a catalyst outlet line 51 leads the gas freed of oxyhydrogen.

If only partial flows of the gas-laden water are degassed with the device according to the invention, the amounts of ignitable gas which are removed from this partial flow can be so small that catalytic destruction in the manner described is not necessary. These small amounts can simply be sent to the Environment. The partial stream that carries larger amounts of gas, which are quite critical, can then be degassed using another method. Such a combination is shown in FIG. 8. The water to be sterilized is supplied to the water sterilization system 37 via a supply line 59. The gas-laden water emerging from it is divided into partial strands via a main feed line 57 and continues to flow via feed lines 1 and 52. The degassing device 38 according to FIGS. 1 to 7 degasses the partial flow which is fed in via the feed line 1, the degassed water passing through the consumer line 22 to the consumers, such as the spray handpiece, the coolant system or the tartar removal device.

The partial flow in the feed line 52 leads to a degassing tank 55 which works according to a different principle and which supplies the water degassed by it to the consumers via an additional line 61, e.g. the fountain system or the drain.

Claims

PATENT CLAIMS

1. Device for degassing the water sterilized in a water decontamination system of a dental treatment device for the dental

Treatment instruments and the other water consumers assigned to a dental patient chair, characterized in that the water sterilization system (37) via a supply line (1) and a first controllable valve arrangement (4, 5, 23, 28, 29) with the input lines (6, 7, 32, 33) at least two closed containers (8, 9) are connected, which are connected via outlet lines (10, 11, 34, 35) and a second controllable valve arrangement (12, 13, 25, 36) a consumer line (22) leading to the water consumers and via suction lines (14, 15, 18, 19, 26, 30) provided with valves (16, 17, 24, 28, 29) opening into the containers (8, 9), 31, 32, 33) are connected to a vacuum generator (41) and that the valves (4, 5, 23, 28, 29; 12, 13, 25, 36; 16, 17, 24, 28, 29) can be actuated by a control circuit in such a way that the containers (8, 9) alternately with the vacuum generator (41) or with the supply line (1) and the consumers line (22) are connected.

2. Device according to claim 1, characterized ge indicates that the suction lines (14, 15, 32, 33) open into the upper part of the container (8, 9).

3. Device according to claim 2, characterized ge indicates that the upper part of the container ter (8, 9) to the mouth of the suction lines (14, 15, 32, 33) has inclined walls.

4. Device according to one of claims 1 to 3, characterized in that the input lines (6, 7), the output lines (10, 11) and the suction lines (14, 15) each with an electromagnetically actuated shut-off valve (4, 5th , 12, 13, 16, 17) are provided.

5. Device according to one of claims 1 to 3, characterized in that the Ein¬ input lines (6, 7), the output lines (10, 11) and the suction lines (14, 15) of the two containers (8, 9) each one 3/2-way valve (23, 24, 25) which can be switched electromagnetically is assigned.

6. The device according to claim 5, characterized ge indicates that the 3/2-way valve (23) assigned to the input lines (6, 7) has one input-side and two output-side connections, while the two the suction lines (14, 15) and the 3/2-way valves (24, 25) assigned to the output lines (10, 11) have two connections on the input side and one connection on the output side.

7. Device according to one of claims 1 to 3, characterized in that the inlet and suction lines of each container (8, 9) are realized by common lines (32, 33) which are connected to the main connection of 3 / 2- Directional valves (28, 29) are connected, whose changeover connections are connected in the opposite direction to the supply line (1) and a common vacuum line (26).

8. The device according to claim 7, characterized in that the two output lines (34, 35) are connected to the changeover connections of a 3/2-way valve (36).

9. Apparatus according to claim 7 or 8, characterized in that the respective 3/2-way valve (28, 29) can be switched back and forth by the control circuit for a short injection phase during the suction phase.

10. The device according to claim 7 or 8, characterized in that when switching the common lines (32, 33) zugeordne¬ th 3/2-way valves (28, 29) each have two containers (8, 9) are connected to the feed line (1) via the 3/2-way valves (28, 29) during a short pressure build-up phase.

11. Device according to one of the preceding claims, characterized in that the Behälter¬ ter (8, 9) are provided with stirrers, vibrating devices or a heating device.

12. Device according to one of the preceding claims, characterized in that the common vacuum line (26) is connected to a liquid separator (40) connected upstream or downstream of the vacuum generator (41).

13. The apparatus according to claim 12, characterized in that the liquid separator (40) is associated with a catalyst (48) for converting oxyhydrogen gas into water.

14. Device according to one of the preceding claims, characterized in that in the water disinfection system (37), disinfection takes place by means of an anodic oxidation of the water.

15. Device according to one of the preceding claims, characterized in that the water decontamination system has a main supply line (57) which feeds two branch lines (52, 1) with partial flows, one of which with the supply line (1) of the degassing device ( 38) and the other is connected to a degassing tank (55) through which the second partial stream is degassed.