GB1578269A

GB1578269A - Air humidifier

Info

Publication number: GB1578269A
Application number: GB21589/77A
Authority: GB
Original assignee: Defensor AG
Current assignee: Defensor AG
Priority date: 1976-05-24
Filing date: 1977-05-23
Publication date: 1980-11-05
Also published as: IT1080852B; FR2352570B1; DE2718808A1; FR2352570A1; NL7705696A; SE7704818L; ES459041A1; CH601740A5; JPS534340A

Description

(54) AIR HUMIDIFIER (71) We, DEFENSOR, a Joint Stock Company organised under the laws of Switzerland, of Binzstrasse 18, 8045 Zurich, Switzerland, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement-: This invention pertains generally to a gas-liquid contact apparatus for moistening the air delivered by a hot-air furnace or the like by the addition of water-vapor or steam. It particularly relates to such an apparatus designed for continuous duty wherein means are provided for preventing the build-up of mineral precipitate within the apparatus. The invention particularly concerns an air humidifier having an evaporation vessel with at least one heating element arranged therein.A control basin maintains the water at a constant predetermined level in the evaporation vessel and includes a connection for a water discharge.

Air humidifiers of the type shown in this invention are usually supplied with water from a water main system. Depending on the geographic area, tap water contains a greater or lesser amount of dissolved minerals which, with the heating and evaporation of the water, are retained and precipitated in the evaporation vessel. The precipitated minerals deposit on the heating elements and on the inner walls of the evaporation vessel and form a crust. With time, these deposits can fill a large portion of the evaporation vessel and, as a result, impede its satisfactory functioning. It is therefore necessary to remove these deposits periodically with mechanical or chemical means.

For this purpose, it is known to loosen the encrusted deposits mechanically with tools and to clear the evaporation vessel manually. This method is labor-intensive and requires a disturbing interruption in operation. In the removal with chemical means, the encrusted deposits are dissolved with an acid-containing solution and removed by flushing. During the solution process, poisonous vapors develop which can be dangerous for persons working with them. The application of this method also requires a disturbing interruption of the operation. An additional disadvantage of the use of chemical means is their subsequent impact on the environment upon discharge into waste water systems not ordinarily designed to handle such wastes.

For this purpose of preventing an encrustation, it is also known to eliminate the minerals which are dissolved in the water through prior water purification treatment such as by ion-exchange treatment.

Alternatively an apparatus can be provided for adding chemicals to treat the tap water. While the minerals which are contained in the water are not removed in this manner, they no longer form any encrustations and can be quite easily removed by flushing. These methods require a relatively high expense through the acquisition of the appropriate apparatus and through maintenance work.

It is therefore an object of the invention to provide an air humidifier having an evaporator in such a manner that the expenses for its maintenance are minimal, yet with substantially continuous operation and without mineral precipitate build-up.

According to the present invention there is provided an air humidifier comprising: a) an evaporation vessel for containing a body of water to be evaporated, b) at least one heating element positioned within the evaporation vessel for heating the body of water, c) a control basin fluidly connected to the evaporation vessel for controlling the level of the body of water at a preselected level, d) a connection, located between the evaporation vessel and the control basin, with a water discharge drain for permitting the simultaneous flow of water from the evaporation vessel and control basin into the drain, and e) a replaceable insert lining the evaporation vessel.

In a special embodiment, the insert con tainer can be a plastic bag. The deposits then accumulate in this bag and can be simply removed by the removal of the bag from the evaporation vessel. The bag can be emptied in order to reuse it, but still more appropriately, it can be discarded with its contents and replaced in the evaporation vessel with a new, plastic bag. In comparison with the known cleaning methods, a considerable saving in labor expense results. The interruption in operation associated with the replacement of the bag is short and hardly disturbing. In addition a bag of this type is relatively inexpensive. An additional advantage is that the inside walls of the evaporation vessel are no longer exposed to the considerable wear and tear of cleaning and the evaporation vessel therefore has a longer life.

In another embodiment, unions for the communicating connection between the control basin, the evaporation vessel, and the water discharge pipe can be combined and be arranged on the input side of the evaporation vessel containing the insert container. By means of this connection, fresh water flows in continuously during the evaporation as replacement for the evaporating water, thus preventing an encrustation which would otherwise form in the connection.

The communicating connection can be configured in the shape of a pocket or as a thermal trap in order to prevent heated water and thus deposits from the evaporation vessel from reaching the control basin. In this manner, the control basin remains clean and the deposits can only accumulate in the bag situated in the evaporation vessel.

An air pressure equalization line, which is arranged on the control basin, can assure that the same pressure and thus the same level will prevail in the control basin as in the evaporation vessel. In this manner, faulty signals and drying up of the heating elements due to differential level can be avoided.

Other features and advantages of an apparatus according to this invention will become apparent to those of ordinary skill in the art upon consideration of the following description and the accompanying figure.

The single figure is a schematic illustration of an air humidifier incorporating the several features of this invention.

A control basin 1 communicates through a pipe or tube line 2, with an evaporation vessel 3. Through a floating valve 4 fresh water is fed into control basin 1 by means of an inlet line 5 and maintained at a preselected level 6. A heating element 7, which can be an electrical heating element or a tube coil into which is fed hot water or steam, is inserted in evaporation vessel 3.

Evaporation vessel 3 is lined with a replaceable insert container 8.

Pipe 2 ends on a side of evaporation vessel 1 and therefore the insert container 8 also has an opening at this point. In the illustrated embodiment, the insert container 8 is a bag which is held at the upper edge of evaporation vessel 3 by means of a clamping device 9. An additional clamping device 10 seals bag 8 with respect to evaporation vessel 3, at the junction of pipe 2.

The height of the junction of pipe 2 is so selected that it is above an area in which the deposits accumulate in bag 8, but below the predetermined level 6 of the water.

In the upper area of evaporation vessel 3, a water-vapor line 12 is coupled with a water-vapor removal stud 11, the watervapor line 12 leading to a pipe 13, which has nozzles 22 for emitting water-vapor into an air duct 14.

An electrical float switch 15, which initiates the energy supply to heating element 7 shortly before reaching level 6, is arranged in control basin 1. This prevents a heating of the evaporation vessel 3 when the water level is too low.

A pressure equalization line 16 is located between control basin 1 and air duct 14, so that the same pressure as in the evaporation vessel 3 prevails in control basin 1.

As an overflow protection, an open overflow pipe 17 is arranged in control basin 1, connected with a discharge pipe 19 through a siphon 18 which serves as an odor lock.

A discharge valve 20 is inserted between the communicating connection 2 and discharge pipe 19.

The communicating connection 2, which is formed by pipe or tube line, assures the maintenance of the same level 6 in the evaporation vessel 3 as in the control basin 1. In addition, the communicating connection 2 is arranged in the shape of a pocket and thus forms a heat trap between evaporation vessel 3 and control basin 1.

This arrangement has the advantage that the control elements 4 and 15 are located outside of the evaporation vessel and, by means of the heat trap, heated water from the evaporation vessel 3, and thus mineral deposits, are prevented from reaching the control basin 1.

In the operation of the air humidifier according to the invention, the control basin 1 and the evaporation vessel 3 are filled with water up to level 6. Float switch 15 releases energy to heating element 7.

The water in the evaporation vessel 3 is thus heated to increase evaporation. The water-vapor or steam which forms flows through line 12 to nozzle-containing pipe 13 and is there blown into air duct 14, where it admixes with the flowing air and humidifies it.

Through the evaporation of water, the concentration of dissolved minerals in the remaining water increases constantly. In order to maintain the concentration within limits and thus to delay the precipitation of minerals, the water which is in the evaporation vessel 3 is diluted periodically by temporarily opening the discharge valve 20, which can be a magnetic valve, by means of a time control device 21 so that water flows out through discharge pipe 19. In this discharge process, the hot water from the evaporation vessel 3 mixes with the cold water simultaneously discharging from the control basin 1. In this manner, a thermal overload of the discharge valve 20 and of the waste water installation is avoided.The outlet of pipe 2 emerges from the side of the evaporation vessel 3 at a sufficient height to prevent the discharging of lime particles which if carried along with the water could foul the discharge valve 20. Following the partial emptying of the evaporation vessel 3, the discharge valve 20 is closed again, so that fresh water can again flow in.

The heating elements 7 clean themselves automatically through bursting of the deposits, because the deposits form an insulating layer, which leads to a temperature increase in the heating elements 7. The deposit accumulated in the insert container 8 can be periodically removed by replacing the insert container, the frequency of replacement being a function of the hardness of the water and the number of operating hours. This replacement of the insert container 8 is the only periodic maintenance work for satisfactory functioning of the air humidifier.

WHAT WE CLAIM IS: 1. An air humidifier comprising: a) an evaporation vessel for containing a body of water to be evaporated, b) at least one heating element positioned within the evaporation vessel for heating the body of water, c) a control basin fluidly connected to the evaporation vessel for controlling the level of the body of water at a preselected level, d) a connection, located between the evaporation vessel and the control basin, with a water discharge drain for permitting the simultaneous flow of water from the evaporation vessel and control basin into the drain, and e) a replaceable insert lining the evaporation vessel.

2. The air humidifier of claim 1 further comprising a clamping device situated at an upper edge of the evaporation vessel and wherein the replaceable insert lining is a bag clamped in the clamping device.

3. The air humidifier of claim 1 wherein the connection between the evaporation vessel and the control basin connects to a side of the evaporation vessel below the preselected level of the body of water but above a region wherein substantial mineral deposition occurs.

4. The air humidifier of claim 1 wherein the connection between the evaporation vessel and the control basin is configured in the shape of a pocket thus forming a thermal trap.

5. The air humidifier of claim 1 further comprising an air pressure equalization line connected to the control basin above the preselected level of the body of water.

6. The air humidifier of claim 1 further comprising an open overflow pipe arranged within the control basin and connected to the water discharge drain by way of a siphon serving as an odor lock. 7. The air humidifier of claim 1 wherein the connection with the water discharge drain further comprises a valve situated between the connection and the drain for controlling the discharge of water into the drain.

8. The air humidifier of claim 7 wherein the valve is a magnetic valve connected to a time control device for periodically opening the valve.

9. The air humidifier of claim 1 wherein the heating element is an electrical resistance heating element.

10. An air humidifier comprising: a) an evaporation vessel for containing a body of water to be evaporated, b) at least one heating element positioned within the evaporation vessel for heating the body of water, wherein the heating element is an electrical resistance heating element, c) a control basin fluidly connected to the evaporation vessel for controlling the level of the body of water at a preselected level, wherein an air pressure equalization line is connected to the control basin above the preselected level of the body of water, and wherein an open overflow pipe is arranged within the control basin and connected to the water discharge drain by way of a siphon serving as an odor lock, d) a connection, located between the evaporation vessel and the control basin, with a water discharge drain for permitting the simultaneous flow of water from the evaporation vessel and control basin into the drain, wherein the connection connects to a side of the evaporation vessel below the preselected level of the body of water but above a region wherein substantial mineral deposition takes place, and wherein the connection is configured in the shape of a pocket thus forming a thermal trap,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. where it admixes with the flowing air and humidifies it. Through the evaporation of water, the concentration of dissolved minerals in the remaining water increases constantly. In order to maintain the concentration within limits and thus to delay the precipitation of minerals, the water which is in the evaporation vessel 3 is diluted periodically by temporarily opening the discharge valve 20, which can be a magnetic valve, by means of a time control device 21 so that water flows out through discharge pipe 19. In this discharge process, the hot water from the evaporation vessel 3 mixes with the cold water simultaneously discharging from the control basin 1. In this manner, a thermal overload of the discharge valve 20 and of the waste water installation is avoided.The outlet of pipe 2 emerges from the side of the evaporation vessel 3 at a sufficient height to prevent the discharging of lime particles which if carried along with the water could foul the discharge valve 20. Following the partial emptying of the evaporation vessel 3, the discharge valve 20 is closed again, so that fresh water can again flow in. The heating elements 7 clean themselves automatically through bursting of the deposits, because the deposits form an insulating layer, which leads to a temperature increase in the heating elements 7. The deposit accumulated in the insert container 8 can be periodically removed by replacing the insert container, the frequency of replacement being a function of the hardness of the water and the number of operating hours. This replacement of the insert container 8 is the only periodic maintenance work for satisfactory functioning of the air humidifier. WHAT WE CLAIM IS:

1. An air humidifier comprising: a) an evaporation vessel for containing a body of water to be evaporated, b) at least one heating element positioned within the evaporation vessel for heating the body of water, c) a control basin fluidly connected to the evaporation vessel for controlling the level of the body of water at a preselected level, d) a connection, located between the evaporation vessel and the control basin, with a water discharge drain for permitting the simultaneous flow of water from the evaporation vessel and control basin into the drain, and e) a replaceable insert lining the evaporation vessel.

6. The air humidifier of claim 1 further comprising an open overflow pipe arranged within the control basin and connected to the water discharge drain by way of a siphon serving as an odor lock.

7. The air humidifier of claim 1 wherein the connection with the water discharge drain further comprises a valve situated between the connection and the drain for controlling the discharge of water into the drain.

and wherein the connection with the water discharge drain further comprises a valve situated between the connection and the drain for controlling the discharge of water into the drain, and wherein the valve is a magnetic valve connected to a time control device for periodically opening the valve, and e) a replaceable insert lining the evaporation vessel, clamped in a clamping device situated at an upper edge of the evaporation vessel.

11. An air humidifier substantially as herein described with reference to and as illustrated in the accompanying drawing.