JPH10281501A - Humidifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable sufficient prevention of hot water on the evaporating dish side from moving to the water receiving dish side through a communication passage opened upward, by a structure of which the structural member is made three-dimensional in a small degree and which is simple and inexpensive. SOLUTION: A communication passage 16 which connects a water receiving dish 7 and an evaporating dish 9 so that they are kept at the same level and which is opened upward has a roundabout passage 16a through which water supplied to the water receiving dish 7 goes around an opening part of the evaporating dish 9 and then runs into the evaporating dish 9. The communication passage 16 is made long and hot water on the evaporating dish 9 side is prevented from moving to the water receiving dish 7 side, by the regular movement of the water flowing from the water receiving dish 7 side to the evaporating dish 9 side. Even when the hot water on the evaporating dish 9 side moves to the water receiving dish 7 side, the temperature thereof is lowered due to mixing with-cold water in a long course.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a humidifier, and more particularly to a humidifier in which supplied water is heated by a heater to evaporate the water to be used for humidification.

[0002]

2. Description of the Related Art A humidifier of this type is usually provided with a water supply tank detachably mounted and supplied with a water tray to maintain a predetermined water level, and a heater for heating and evaporating the supplied water with a heater for humidification. The evaporating dish is provided with a communication path for connecting the water tray and the evaporating dish so as to maintain the same water level.In the evaporating dish, a certain amount of water is supplied from the water supply tank while the predetermined level is maintained. Humidification can be performed by generating steam. When the water supply tank is empty, the humidifier is used repeatedly by removing the water supply tank, refilling the water, and re-attaching the water supply tank.

On the other hand, as water evaporates and concentrates in the evaporating dish, minerals and the like contained in the water gradually adhere to the evaporating dish and the above-mentioned communication path connected thereto.
The humidifier accumulates according to the degree of repeated use.

[0004] Since the evaporating dish has an upwardly open structure, it is relatively easy to clean and can remove attached minerals. However, if the communication path is a closed pipe, it is difficult to clean it, and it is difficult to sufficiently remove the attached minerals. For this reason,
There was a problem that the humidifier reached its end of life early due to clogging of the pipeline.

As a solution to this problem, a device as shown in FIG. 11 has already been provided.

As shown in FIG. 11, a water supply tank a is mounted so as to be detachable and is supplied with water so as to maintain a predetermined water level, and a supplied water is heated by a heater h. An evaporating dish c for evaporation and humidification is provided, and a communication path d opened upward connecting the water receiving tray b and the evaporating dish c so as to maintain the same water level. When the communication path d is open upward as described above, the entire area around the water can be washed together with the evaporating dish c and the water receiving tray b which are also open upward, thereby removing attached minerals and the like. It is easy to operate and does not cause an early life due to clogging.

However, when the communication path is opened upward, the movement of the water is free, and the hot water on the evaporating dish shifts little by little to the water on the water scoop, and moves to the water scoop. There is a problem in that heat degradation is caused in the portion of the water tray side having no structure, and in order to solve the problem, the water tray side is also made to have a heat-resistant structure, resulting in high cost.

In the conventional device shown in FIG. 11, a deep groove e is provided in the middle of the communication path d so as to cross the communication path d, and the baffle f is inserted into the groove e from above. This baffle f
Is provided integrally with a suitable attaching / detaching member such as a lid member, and is heated on the side of the evaporating dish c on the cold water flowing from the side of the water receiving dish b to the evaporating dish through the baffle plate f. There is hot water, which replaces the cold water below and moves downward to prevent the baffle f from moving toward the water receiving pan. This solves the problem that the hot water on the side of the evaporating dish c moves to the side of the water receiving dish b.

[0009]

However, the groove e needs to be relatively deep and narrow in order to sufficiently prevent the hot water on the side of the evaporating dish c from flowing to the side of the water receiving dish b. Inconvenient.

An object of the present invention is to provide a humidifier capable of sufficiently preventing the hot water on the evaporating dish side from being transferred to the water receiving dish side through the communication path opened upward with a structure that is easy to clean. .

[0011]

A humidifier according to the first to third aspects of the present invention is a humidifier, wherein a water supply tank is mounted so as to be detachable, and a water receiving tray for supplying water so as to maintain a predetermined water level, and a heater for supplying water to the heater. An evaporating dish heated and evaporated for humidification,
An upwardly open communication path connecting the water tray and the evaporating dish so as to keep the same water level is provided, and each of the communication paths between the water tray and the evaporating dish is opened upward as in the conventional case. This makes it easy to clean and easily remove attached minerals and the like, so that it is possible to prevent the communication path from being clogged and reaching the end of its service life early.

[0012] In order to achieve the above object, the invention according to claim 1 is characterized in that the communication path is such that water supplied to the water receiving tray flows into the evaporating dish after bypassing around the mouth of the evaporating dish. It is characterized by having a detour, this detour only slightly expands around the mouth of the evaporating dish, is shallow and easy to clean, and the components are particularly three-dimensional. Prevents hot water from moving from the evaporating pan to the water pan due to the steady flow of water from the water pan to the evaporating pan through a long communication path with a simple, low-cost structure In addition, even if the hot water on the evaporating dish side shifts to the water receiving dish side while replacing the cold water from the water receiving dish side, the communication path is long and it is difficult to reach the water receiving dish side. The temperature can be reduced by repeated mixing with cold water. Since, it is possible to solve the problem of hot water is transferred to the water receiving tray side.

According to a second aspect of the present invention, in the communication path, a tubular wall detachably fitted in the downwardly recessed portion is fitted from above, and water in the water receiving tray flows up and down into the evaporating tray. It is characterized by having a detour of a double structure, a detachable cylindrical wall is fitted in the recess to form a narrow double structure, and high-temperature water in the evaporating dish is In addition to extending the path, the narrow passage makes it difficult for hot water on the evaporating dish to dive under the low-temperature water on the water receiving dish, effectively preventing hot water in the evaporating dish from flowing into the water receiving dish. Even if the recess is deep, it can be widely opened upward by removing the cylindrical wall, so that it is easy to clean.

The invention according to claim 3 is characterized in that a backflow preventing means for preventing backflow of water on the side of the evaporating tray to the side of the water receiving tray is provided in the middle of the communication path. The backflow prevention means in the middle of the path does not obstruct the flow of water on the evaporating dish side so that water on the water receiving dish side maintains a predetermined water level in accordance with consumption of water on the evaporating dish side. Is prevented from flowing back to the water pan over the backflow prevention means,
The problem that the hot water on the evaporating dish side shifts to the water receiving dish side can be reliably prevented.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the humidifier according to the present invention will be described below with reference to FIGS.

(Embodiment 1) A humidifier according to Embodiment 1 has an overall configuration as shown in FIG. 1 and is made of a synthetic resin bottom member 2 provided with legs 1 made of rubber or the like. The main body is made of a synthetic resin body member 3 that can be attached to and detached from the opening edge of the material 2 and a synthetic resin lid member 4 that can be attached and detached to the opening edge of the body member 3. 5 are formed.

At an intermediate height position of the body member 3, an intermediate bottom 3a is integrally formed and provided.
A water receiving tray 7 for detachably mounting is provided integrally formed, and a steam generating port 11 for connecting an evaporating plate 9 for heating and evaporating water by a heater 8 for humidification is provided integrally. I have.

The water supply tank 6 has a normally-closed valve 1 attached to a synthetic resin lid 12 screwed so as to be detachably attached to an opening 6a thereof.
A water supply port 14 having a water supply port 3 is provided. The lid 12 is fitted to the tank mounting port 7a of the water receiving tray 7 from above to be seated on the tank receiver 7b. Projection 15 integrally formed at the bottom center of the projection
Pushes and opens the normally closed valve 13 so that the water in the water supply tank 6 flows out into the water receiving tray 7.

The water that has flowed out of the water receiving tray 7 flows into the evaporating dish 9 through the communication path 16 shown in FIGS. For example, when a predetermined water level required in a normal use state is reached as shown by a virtual line in FIG.
The water surface reaches the height of the lower end of the water supply port 14 and the water supply port 14
Close up. As a result, the outside water cannot be introduced into the water supply tank 6 through the water supply port 14, and the outflow of the internal water stops.

The water level evaporates and is consumed on the side of the evaporating dish 9 to lower the water level. To compensate for this, water flows from the water receiving dish 7 side to the evaporating dish 9 side, and the water level of the water receiving dish 7 drops. Then, since the water supply port 14 is changed from the state closed by the water surface to the open state, the water in the water supply tank 6 flows out to the water receiving tray 7 until the water supply port 14 is closed by the rise of the water level again, and the water is supplied. . By repeating the water supply and the water supply stop, the water is heated and evaporated by the heater 8 while the evaporating dish 9 is always maintained at a constant water level, and the set amount of steam is constantly generated to achieve the set humidification. To be done.

As shown in FIG. 1, the evaporating dish 9 is applied to the lower surface of the steam generating port 11 via a seal packing 21 and is screwed from below by a plurality of screws 22. As shown in FIGS. 1 and 2, the water supplied to the water receiving tray 7 is connected around the mouth 9 a of the evaporating dish 9, in the specific example of the first embodiment, to the mouth 9 a, as shown in FIGS. It has a detour 16a that bypasses around the steam generation port 11 and then flows into the evaporating dish 9. The detour 16a of the first embodiment includes a passage 16 extending from the water receiving tray 7 to the evaporation tray 9 side.
b is an annular passage formed between the inner annular wall 11a and the outer annular wall 11b around the steam generating port 11 so as to branch from the steam generating port 11, and is substantially true of the connection position of the inner annular wall 11a with the communication path 16b. At the opposite position, there is provided a communication port 23 cut out so that the detour 16a communicates with the steam generation port 11.

As a result, each of the communication paths 16 between the water receiving tray 7 and the evaporating dish 9 is open upward, so that it is easy to clean and remove attached minerals and the like. The problem that the life is reached early is eliminated. At the same time, the bypass 16a only slightly expands around the opening 9a of the evaporating dish 9 or around the steam generating port 11, so that the components do not become particularly three-dimensional, and have a simple and low-cost structure. In this way, it is possible to prevent the hot water on the side of the evaporating tray 9 from being transferred to the side of the water receiving tray 7 due to the movement of water flowing steadily from the side of the water receiving tray 7 to the side of the evaporating tray 9 through the long communication path 16 and to the side of the evaporating tray 9 Hot water is a water tray 7
Even if it shifts to the water tray side 7 while replacing the cold water from the side, the communication path 16 is long and hard to reach the water tray 7 side, and even if it extends, it is repeatedly mixed with the cold water from the water tray 7 side. This will lower the temperature. Therefore, the problem that hot water is transferred to the water receiving tray 7 can be solved.

As shown in FIG. 1, an annular cover plate 24 made of metal or synthetic resin is applied to the bypass 16a.
It is attached so that it can be attached and detached by a plurality of screws 25. The steam generated in the evaporating dish 9 is guided to the screw portion on the outer periphery of the cylindrical wall 24a at the center of the cover plate 24 so that the opening 4a of the cover member 4 is opened.
The steam pipe 26 diverged to the outside is screwed and mounted so as to be detachable. The steam pipe 26 is formed by connecting several members made of synthetic resin by screws or fittings.
Also, a mixing member 26b for mixing the introduced outside air and the diverging steam is provided, and the temperature of the diverging steam is reduced by the introduction and mixing of the outside air. They avoid hot thoughts.

As shown in FIGS. 1 and 3, the heater 8 is a band heater wound around the outer periphery of the evaporating dish 9 and fastened with screws 31, 31. However, there is a problem that the tightening of the heater 8 is gradually loosened due to the repetition of the thermal expansion and the thermal contraction of the evaporating dish 9, and the heater 8 is inadvertently dropped off when the limit is exceeded.

In order to solve this, in the first embodiment,
As shown in FIGS. 1 and 3, a heater drop prevention fitting 32 made of a wire is applied to the bottom of the evaporating dish 9 from below on the diameter line of the evaporating dish 9, and both ends 32 a and 32 a are provided on the outer periphery of the flange of the evaporating dish 9. By engaging and stabilizing the mounting holes 9c, 9c provided at two places on the diameter line of the folded annular wall 9b, even if the heater 8 is to be dropped, it does not come off any more when it hits the heater drop prevention metal fitting 32. The heater 8 can be prevented from dropping carelessly.

A water supply outlet 12a is connected to the lid 12 of the water supply tank 6 so that outside air is introduced into the water supply tank 6 from the center in accordance with the flow of water in the water supply tank 6 from the outer periphery. An inlet 12b is provided to prevent the introduced outside air and the outflowing water from colliding with each other and disturbing each other or generating a sound, so that the water can flow out without disturbance. .

A herb container 26e is provided at a vapor discharge end 26d at the upper end of the vapor pipe 26. When the herb is stored and used in the herb container 26e, the herb component is converted into the vapor discharged to the outside through this portion. Is multiplied and emitted. The water receiving tray 7 is provided with a water level sensor 27 as shown in FIG. 2 and a temperature fuse 28 as shown in FIG. 3, so that the water level becomes dangerous due to no water supply from the water supply tank 6. In addition, it automatically detects that the temperature has risen abnormally due to running out of water, and when such detection is made, the heater 8 is automatically turned off, and at the same time, a sound and various display warnings are issued. I have. Thereby, safety of use can be achieved.

(Embodiment 2) Embodiment 2 is shown in FIG.
As shown in FIG. 5, a communication path 1 from the water receiving tray 7 to the evaporating tray 9
In the middle of 6, there is provided a backflow preventing means 41 for preventing hot water from flowing back from the evaporating dish 9 to the water receiving dish 7. As described above, the backflow prevention means 41 in the middle of the communication path 16 prevents the water on the water receiving tray 7 from flowing toward the evaporating tray 9 so as to maintain a predetermined water level in accordance with the consumption of water on the evaporating tray 9. Since the hot water on the side of the evaporating dish 9 is prevented from flowing back to the side of the water receiving tray 7 beyond the backflow preventing means 41 without disturbing the hot water, the problem that the hot water on the side of the evaporating dish 9 moves to the side of the water receiving side 7 is ensured. Can be prevented.

The backflow prevention means 41 of the second embodiment has a simple structure in which a water wheel 42 is provided so that a half portion thereof faces the communication path 16, and the water wheel 42 has a radial shape around a rotation shaft 42a. A predetermined number of blades 42b are provided, and the water receiving tray 7 side and the evaporating tray 9 side of the communication path 16 are connected to one of the blades 42b.
It is preferred that b is always isolated.

The half of the water wheel 42 facing the communication path 16 is configured such that the water on the water receiving tray 7 constantly flows toward the evaporating dish 9 in accordance with the consumption of water on the evaporating dish 9 side. Since the water in the water receiving tray 7 is constantly sent out to the evaporating dish 9 by rotating in the direction indicated by the arrow in FIG. 5, the hot water on the evaporating dish 9 is constantly rotated in the direction of the arrow. It is possible to prevent the hot water of the evaporating dish 9 from flowing backward to the water receiving tray 7 without inverting the water wheel 42 being rotated and flowing back to the water receiving tray 7 beyond the isolation state. Can be.

In the second embodiment, the bottom member 2 and the body member 3
4 is integrally connected by screws 45 as shown in FIG. 4 so as to prevent inadvertent separation. Such a configuration can be applied to the first embodiment. In addition, steam pipe 2
6 is simply fitted on the steam generating port 11 so that it can be attached and detached, so that there is no steam vent between the two without screwing. This may also be applied to the first embodiment.

(Embodiment 3) Embodiment 3 is described with reference to FIGS.
As shown in FIG. 9, a backflow prevention means 41 including a float valve 51 different from that of the second embodiment is provided. The float valve 51 has a projection 5 integrally formed on the intermediate bottom 3a of the body member 3.
2 and a stopper 53 attached to the upper end of the projection 52 with a screw 50 and an intermediate bottom 3a.
It is provided so as to move up and down according to the water level. The float valve 51 may be a hollow member made of, for example, a synthetic resin so as to be able to respond to the water level of the evaporating dish 9 in the communication path 16. However, even if it is not particularly hollow, it may be made of a lightweight material that floats on water and that can move up and down according to the water level.

A gap 55 is provided between the float valve 51 and the projection 52 so that water from the water receiving tray 7 flows toward the evaporating tray 9.
When the float valve 51 comes into contact with the stopper 53 due to the rise of the water level on the side of the evaporating dish 9, the upper end of the gap 55 is closed by the stopper 53, so that the water on the side of the water receiving dish 7 communicates with the float valve 51 through the communication path 16. It is shut off by the stopper 53 and does not flow to the side of the evaporating dish 9.

When water is consumed on the side of the evaporating tray 9 and the water level falls, the float valve 51 also falls and separates from the stopper 53, so that the gap 55 is opened and the water on the side of the water receiving tray 7 is drained. It flows to the side of the evaporating dish 9 through the communication path 16.

By repeating the above operations, the water in the water supply tank 6 is supplied to the evaporating tray 9 through the water receiving tray 7 and the communication path 16 having the float valve 51, and humidification is performed while maintaining a predetermined water level. .

In this humidified state, even if the hot water flows or moves from the side of the evaporating dish 9 to the side of the water receiving tray 7, such a movement of the hot water occurs.
1 is pressed against the stopper 53, and the float valve 51 is closed.
1 to prevent the water from flowing back to the side of the water pan 7
The disadvantage that the hot water of the evaporating dish 9 flows backward to the water receiving dish 7 through the communication path 16 is eliminated.

In the third embodiment, as shown in FIGS. 6 and 8, the steam pipe portion of the first and second embodiments is omitted, and a steam cover 61 which can be attached and detached is provided instead. 61 covers the steam generating port 11 formed by the seal packing 21 at the lower end thereof.
Vapor scattering prevention cover 61 which is seated on 1 and connected to evaporating dish 9
a at the bottom, herb chamber 61b and steam outlet 6 at the top
1c, the outside air intake port 61d is provided in a wide area range around the trunk, so that the inside becomes a wide space.
As a result, the steam introduced into the inside through the steam scattering prevention cover 61a sucks a large amount of outside air through the wide outside air suction port 61d and rises while sufficiently exchanging heat in a large room, and the steam in the upper portion is cooled down sufficiently in temperature. It goes out to the outside through the discharge port 61c and the herb chamber 61b so that safety can be achieved with a simple structure.

The cover 61 is fitted with an iris so that the lower end can be attached to and detached from the opening of the evaporating dish 9 of the body member 3.
A hook 61e provided on one surface of the upper end is detachably engaged with a part of the engaging hole 71 of the lid member 4 so as to be stably mounted.

The cover 61 according to the third embodiment may of course be formed into a detachable combination which is divided into various parts as required.

(Embodiment 4) Embodiment 4 is similar to FIG.
As shown in FIG. 10, the communication path 16 is configured such that a cylindrical wall 82 that can be attached to and detached from a recessed portion 81 that is recessed partway downward fits from above and water in the water receiving tray 7 is diverted up and down. Has a detour 83 having a double structure flowing into the device.

Since the structure is not substantially different from that of the first embodiment and the like, the same members and portions are denoted by the same reference characters, and redundant description will be omitted.

In the structure of the fourth embodiment, a cylindrical wall 82 which can be attached to and detached from the concave portion 81 is fitted from above to form a narrow bypass circuit 83 having a double structure.
In addition to making the path extending inside the evaporating dish 9
The high-temperature water in the evaporating tray 9 can be effectively prevented from flowing into the water receiving tray 7 because the high-temperature water on the side becomes difficult to dive under the low-temperature water on the water tray 7. Even if it is deep, it can be widely opened upward by removing the cylindrical wall 82, so that it is easy to clean.

Further, the cylindrical wall 82 is formed integrally with the steam generating port 11 which can be attached and detached by a screw 84, and can be attached and detached integrally with the steam generating port 11. However, the detachable structure of the cylindrical wall 82 can be variously designed. A lid 86 as shown in FIG. 10 which can be opened and closed around a shaft 85 is provided at the upper part of the detour 83, and normally the high temperature water on the side of the evaporating dish 9 is closed in the main body 5 by closing this. The lid 86 is opened to make it easier to clean the cylindrical wall 82 and the like. Connecting channel 1 on lid 86
A baffle plate 86a that enters from above into the inside of the evaporator 6 is integrally formed, and thus, it is possible to prevent the high-temperature water in the evaporating dish 9 from moving to the water receiving tray 7 side.

[0044]

According to the first aspect of the present invention, the detour only slightly expands around the mouth of the evaporating dish, and the components are not particularly three-dimensional. With the structure as it is, the movement of water flowing steadily from the water pan to the evaporating pan through the long communication path prevents the hot water on the evaporating pan from moving to the water pan, and the hot water on the evaporating pan is Even if it shifts to the water pan side while replacing the cold water from the water pan side, the communication path is long and it is difficult to reach the water pan side,
Even if it does, the temperature will be lowered by repeated mixing with cold water from the water pan side, so that the problem that hot water moves to the water pan side can be solved.

According to the second aspect of the present invention, a detachable cylindrical wall is fitted into the concave portion to form a narrow double structure, and the path of the high-temperature water in the evaporating dish to the water receiving tray is lengthened and narrow. The passage makes it difficult for the high-temperature water on the evaporating pan to dive under the low-temperature water on the water pan, thereby effectively preventing high-temperature water in the evaporating pan from flowing into the water pan. Even if it is deep, it can be widely opened upward by removing the cylinder wall, so that it is easy to clean.

According to the third aspect of the present invention, the backflow prevention means in the middle of the communication path is provided on the evaporating dish side so that the water on the water receiving dish side maintains a predetermined water level in accordance with the consumption of water on the evaporating dish side. The hot water on the evaporating dish is prevented from flowing back to the water receiving dish side beyond the backflow prevention means without obstructing the flow of hot water on the evaporating dish side, so that the problem that the hot water on the evaporating dish side is transferred to the water receiving dish side is reliably prevented. be able to.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an entire configuration of a humidifier according to a first embodiment of the present invention.

FIG. 2 is a plan view of the humidifier of FIG.

FIG. 3 is a perspective view showing a state in which a heater is attached to an evaporating dish of the humidifier in FIG. 1;

FIG. 4 is a cross-sectional view illustrating an entire configuration of a humidifier according to Embodiment 2 of the present invention.

FIG. 5 is a cross-sectional plan view of the humidifier of FIG.

FIG. 6 is a cross-sectional view illustrating an entire configuration of a humidifier according to Embodiment 3 of the present invention.

FIG. 7 is a plan view showing a backflow preventing means of the humidifier in FIG. 6;

FIG. 8 is an exploded perspective view showing a part of the humidifier of FIG. 6;

FIG. 9 is a cross-sectional view illustrating an entire configuration of a humidifier according to Embodiment 4 of the present invention.

FIG. 10 is a perspective view showing a lid of a communication path of the humidifier in FIG. 9;

FIG. 11 is a sectional view of a main part of a conventional humidifier.

[Explanation of symbols]

 Reference Signs List 6 water supply tank 7 water receiving tray 8 heater 9 evaporating tray 11 steam generation port 14 water supply port 16 communication path 16a, 83 detour 41 backflow prevention means 42 waterwheel 51 float valve 52 projection 53 stopper 55 gap 81 concave section 82 cylindrical wall

Claims (3)

[Claims] 1. A water receiving tray which is detachably mounted and is supplied with water so as to maintain a predetermined water level, an evaporating plate for heating and evaporating the supplied water by a heater to provide humidification, and a water receiving plate. A humidifier provided with an upwardly open communication path that connects the evaporating dish to maintain the same water level, wherein the communication path evaporates after water supplied to the water receiving tray bypasses around the mouth of the evaporating dish. A humidifier having a detour that flows into a dish. 2. A water receiving tray which is detachably mounted and is supplied with water so as to maintain a predetermined water level, an evaporating plate which heats and evaporates the supplied water by a heater to provide humidification, and a water receiving plate. A humidifier having an upwardly open communication path connecting the evaporating dish and the same water level, wherein the communication path is configured such that a detachable cylindrical wall is fitted from above into a concave portion recessed downward. A humidifier having a detour having a double structure in which water in a water receiving tray bypasses up and down and flows into an evaporating tray. 3. A water receiving tray which is detachably mounted and is supplied with water so as to maintain a predetermined water level, an evaporating plate which heats and evaporates the supplied water by a heater to provide humidification, and a water receiving plate. A humidifier provided with a communication path open upward connecting the evaporating dish with the same water level, wherein a backflow preventing means for preventing backflow of water on the evaporating dish side to the water receiving dish side in the middle of the communication path; A humidifier characterized in that a humidifier is provided.