US20240090715A1

US20240090715A1 - Hand dryer and method for operating a hand dryer

Info

Publication number: US20240090715A1
Application number: US18/255,522
Authority: US
Inventors: Niklas Kreyenhagen
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-12-01
Filing date: 2021-12-01
Publication date: 2024-03-21
Also published as: EP4255269A1; JP2023551341A; WO2022117668A1

Abstract

A hand dryer intended to avoid potential health risks particularly effectively includes a shroud like housing with an interior space having an opening for parts of the body to be dried; a first filter element for filtering air taken in; at least one nozzle, by which the filtered air is conducted out into the interior space of the housing; a second filter element, by which the air conducted into the interior space of the housing by the nozzle is filtered; and an outlet, by which the air filtered by the second filter element is conducted out of the housing. A method for operating a hand dryer is also related.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a 35 U.S.C. § 371 National Stage patent application of PCT/EP2021/083813, filed on 1 Dec. 2021, which claims the benefit of German patent application 10 2020 131 880.4 filed 1 Dec. 2020, German patent application 10 2021 116 869.4 filed 30 Jun. 2021, and German patent application 10 2021 117 593.3 filed 7 Jul. 2021, the disclosures of which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a hand dryer according to an independent claim and to a method for operating a hand dryer according to another independent claim.

BACKGROUND

Hand dryers drying the hands with an air flow directed onto the hands are well known from the prior art. In the known hand dryers, the hands are inserted into a housing and dried there by an air flow. Generally, the housings are open on the sides. Thus, water droplets blown away by the air flow, and also the air coming off from the hands, can get out of the housing on the open sides. Both the exhaust air discharged into the surrounding space and the water droplets may contain contaminations and, in particular, bacteria or viruses. They then get into the environment unimpededly.
Accordingly, such hand dryers known from the prior art are not very hygienic and possibly even pose a health risk due to the potential dispersal of bacteria and viruses into the surrounding space.

SUMMARY

The disclosure provides a hand dryer and a method for operating a hand dryer by means of which potential health risks can be avoided particularly effectively.
According to the disclosure, the advantage is achieved with the features of the independent claims. Other practical embodiments and advantages are described in connection with the dependent claims.
A hand dryer according to the disclosure comprises a pot-like housing with an interior space with at least one opening for body parts, preferably hands, to be dried. In other words, this is a housing which encloses an interior space all around, with the exception of at least one opening for inserting the body parts (hands). In particular, the opening is arranged at the top side of the housing, so that the hands can be inserted into the housing from above in a downward direction. A separate opening for each hand may also be provided. In this case, the one opening or two openings are designed to be of such a size that the hands can be inserted into the openings without touching the edge of the opening. In particular, the interior space has a rectangular or slit-like configuration, so that two hands extended so as to be flat can be comfortably inserted into the interior space. In particular, the hand dryer is configured for attachment to a wall and has corresponding attaching portions and suitable attaching means.
The hand dryer further comprises a first filter element for filtering drawn-in air. For this purpose, the air is drawn in from the environment of the housing via an inlet and guided through the filter. This is followed by at least one nozzle for discharging the filtered air into the interior space of the housing. Via the at least one nozzle, the filtered air is directed onto the hands in order to dry them. The air discharged from the nozzles flows towards the interior of the housing, so that, if possible, no air ends up in the surrounding space. In particular, several nozzles distributed across the interior space are provided for discharging the filtered air. Preferably, the hands need to be pushed preferably rather deeply into the housing in order to avoid or reduce the flow-back of air into the surrounding space.
The hand dryer further comprises a second filter element for filtering the air fed by the nozzle into the interior space of the housing. The exhaust air that has already come into contact with the hands is to be filtered with the second filter element. In particular, one or several openings, through which the air coming off from the hands can escape from the interior space, are provided in a lower region of the interior space of the housing. In addition, the housing comprises an outlet for discharging the air filtered by the second filter element from the housing. In particular, at least one connection pipe, which guides the air flowing out of the interior space towards the filter and the outlet in a targeted manner, is connected to the interior space. In particular, the at least one opening disposed in the interior space for extracting the exhaust air is arranged such that no water is extracted through it. For this purpose, the at least one opening is arranged at a higher level than a collecting region for the water.
With the hand dryer according to the disclosure, not only the air from the environment, which was drawn in and used for drying, is filtered, but also the exhaust air that was in contact with the hands in order to dry them. Accordingly, the air released into the environment is also filtered air which is as free as possible from bacteria and viruses. Due to the pot-like, closed housing, the exhaust air, in particular, cannot get out of the housing directly. The environment of the hand dryer according to the disclosure is not polluted with bacteria or viruses and thus, persons in the environment of the hand dryer are protected from a potential infection.
In particular, the first filter element and/or the second filter element is a HEPA filter, wherein HEPA stands for “High-Efficiency Particulate Air”. HEPA filters are filters well suited for separating suspended matter from the air. In particular, HEPA filters of the filter classes 13 or 14 are suitable for a use according to the disclosure. Moreover, it may be provided that one or more prefilters are disposed upstream of a HEPA filter, in order to reduce the burden on the HEPA filter.
In one practical embodiment of the hand dryer according to the disclosure, the at least one nozzle for discharging the filtered air into the interior space is arranged in the region of the opening of the interior space and directed towards the interior space. In particular, several nozzles are distributed around the opening. The arrangement of the nozzles provides support for as little air as possible getting through the opening—and thus unfiltered—into the environment.
In particular, the air flows of the intake air and exhaust air are conveyed independently of each other. Thus, the hand dryer has a first conveying element for drawing in air from the environment, in particular a pump, fan or ventilator connected to a motor. In addition, the hand dryer has a second conveying element for extracting the air located in the interior space and for discharging it from the housing. This may also be a pump, fan or ventilator connected to the same or, in particular, a further motor. A particularly efficient extraction of the exhaust air that has been in contact with the hands is realized by the second conveying element, and it is thus avoided that unfiltered exhaust air, with the bacteria and viruses that may possibly be present therein, gets into the environment.
In particular, the first conveying element and the second conveying element can be operated independently of each other. Thus, the hand dryer according to the disclosure offers the advantage of different operating modes. For example, only the second conveying element may be activated, and thus, air from the environment of the hand dryer may be drawn in, primarily via the opening of the housing, and cleaned. Thus, the hand dryer may serve for filtering the ambient air in a time in which it is not in use for drying hands.
In particular, the hand dryer has sensors, which detect an insertion and/or removal of hands, or generally of objects, into the interior space of the housing. The sensors are preferably connected to a control system via which the first conveying element and/or second conveying element can be controlled.
In particular, the hand dryer has an operating unit, such as a touchscreen. In particular, the operating unit is arranged within the housing and accessible via a door. In particular, the operating parameters of the first conveying element and/or second conveying element can be adjusted by means of the operating unit. In particular, the operating unit is connected to the control system for this purpose.
The hand dryer can be operated for a particularly great length of time if the first filter element and/or the second filter element are replaceable. In this case, the filter may be replaced after a set interval or after a set number of uses of the hand dryer.
In addition, an air curtain may be arranged in the region of the opening for the hands, which additionally has the effect that no unfiltered air gets out of the interior space into the environment.
Besides the filtering of the drawn-in air and the discharged air, the treatment of the water blown off from the hands also plays a role, because bacteria or viruses may also be present in the water droplets. In another practical embodiment, the hand dryer has a collection device for liquid in the interior space of the housing, and particularly at the bottom of the interior space. In particular, the collection device has a funnel-shaped configuration and, with a drain, forms the lowermost point of the housing. Thus, the liquid located in the interior space is collected as efficiently as possible.
The transport of the water droplets towards the collection device can be supported by a downwardly directed air flow generated by the at least one nozzle and/or the air extraction means located in the lower region of the interior space.
In particular, a filter for cleaning the collected liquid is additionally provided in order to remove viruses and bacteria also from the waste water. This provides for additional protection, and the hand dryer is particularly safe.
The collection device may be connected to a collection container, so that the hand dryer can be installed and operated independently of a drain pipe. From the drain of the collection device, the liquid preferably runs through the filter and then into the collection container.
In another practical embodiment of the hand dryer according to the disclosure, the collection container has a filling level indicator. It is thus possible to recognize as quickly as possible if the collection container has to be emptied. The collection container may be emptied via a valve. Alternatively or additionally, the collection container is configured like a drawer and can be pulled from the housing.
In order to make the hand dryer particularly safe also for the user, the housing is at least partially, and in particular in the region of the interior space, provided with an antibacterial and/or antiviral coating. In this case, particularly the regions of the hand dryer with which the hands may possibly come into contact for drying are provided both with an antibacterial and an antiviral coating. Such areas are primarily located around the opening and in the interior space of the housing.
It is also conceivable to arrange a UV source in the interior space, which is suitable for disinfecting the interior space. This UV source may also be replaceable. In particular, a UV source is also arranged immediately upstream of the first filter element and/or second filter element in order to clean the flowing air and/or the corresponding filter element.
In another practical embodiment, the housing has a door via which the interior of the housing is accessible. In particular, the filter elements and/or the collection container and/or a UV source can be replaced if the door is open. Moreover, the operating unit may only be accessible if the door is open. In particular, the door can be locked, and the interior of the housing is only accessible using a key.
Moreover, the hand dryer may have a device for hand disinfection. For this purpose, the hand dryer has a container for disposing disinfectant which is connected to at least one opening in the interior space of the housing. Disinfectant can be conveyed from the container to the at least one opening by means of a pump. The disinfectant is then sprayed onto the hands in the interior space. In particular, the openings are also configured in the form of nozzles. The disinfectant that drops off from the hands or misses the hands also reaches, preferably via the collection device, the collection container of the hand dryer in which the water is also collected. In particular, the container for the disinfectant is accessible such that disinfectant can be replenished.
In particular, the spraying of disinfectant onto the hands may be activated by a user by means of a key or button on the outside of the housing or the above-mentioned operating unit on the inside of the housing. The activation of this function is possible either before, after or during the hand drying process.
In another practical embodiment of the hand dryer according to the disclosure, the latter has a display. In particular, the display is arranged on the top side or above the hand dryer. The display is suitable for displaying videos or images. The videos or images may be advertisements or notices, for instance. The contents that are supposed to be displayed on the display may, in particular, be transmitted to the device wirelessly, particularly via WLAN or Bluetooth. The transmission of contents to the display may be password-protected.
The disclosure also relates to a method for operating a hand dryer as described above, wherein the hand dryer has a first conveying element and a second conveying element that can be operated independently of each other, and wherein the first conveying element and the second conveying element are switched on in case of a detection of hands in the interior space, and wherein the first conveying element and/or the second conveying element are switched on for a defined time interval during a period in which no hands are disposed in the interior space.
If hands or the insertion of any object into the interior space is detected, then, as described above, the first and second conveying elements are started and air is drawn in from the environment via the inlet, conveyed into the interior space onto the hands to be dried, extracted again via the openings in the interior space and conveyed to the outlet. During a time period in which there are no objects in the interior space, the first conveying element and/or second conveying element are then switched on for a defined time interval. The two conveying elements then draw in air from the environment via the inlet and/or the opening, and the ambient air is filtered. In particular, it is possible that only the first conveying element or only the second conveying element are switched on. In particular, only the second conveying element is switched on. The second conveying element then draws air from the environment via the opening of the interior space of the housing and filters it.
On the whole, the hand dryer can thus also be used for filtering the ambient air. In this case, the operation of the first conveying element and/or second conveying element may be continued for a defined time interval immediately subsequent to drying the hands, or they may be activated independently thereof, or be switched on permanently. In this case, the frequency of the activation of the first conveying element and/or conveying element, the shut-off delay and/or the duration of the activation can be adjusted in particular by means of the operating unit. For example, the following parameters can be adjusted:

- Whether and for how long the first conveying element and/or the second conveying element continues to run after a hand drying process (the second conveying element, for instance, continues to run for 20 seconds after 5 drying processes).
- When and for how long the first conveying element and/or the second conveying element are switched on, irrespective of a detected presence of hands (e.g. for 30 seconds every 5 minutes).

In particular, only the second conveying element may be activated for several seconds or even minutes. The first conveying element is additionally switched on particularly when the presence of hands is detected by the sensors.
For detecting the presence of hands or of an object in the interior space, the hand dryer has, in particular, at least one sensor. The sensor may be a motion sensor or light barrier, for instance. In particular, the sensors also detect if the hands or an object are removed again from the interior space and then—possibly after a defined time of continued operation—switch the first conveying element and the second conveying element off again. Thus, a particularly energy-saving operation of the hand dryer can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS

Further embodiments and advantages are described below in connection with the Figures. In the Figures:

FIG. 1 shows a first embodiment of a hand dryer in a schematic cross-sectional view,

FIG. 2 shows a second embodiment of a hand dryer in a schematic perspective view obliquely from above, and

FIG. 3 : shows the hand dryer from FIG. 2 in a rear view.

DETAILED DESCRIPTION OF THE DRAWINGS

A hand dryer 10 according to a first embodiment is schematically shown in FIG. 1 . The hand dryer 10 comprises a pot-like housing 12, wherein an interior space 14 is accessible via an opening 16 for body parts to be dried. The hand dryer 10 is arranged on a wall 18.
The hand dryer 10 further has an inlet 20 for drawing in air from the environment. Here, the inlet 20 extends on a side surface of the hand dryer 10 across a large part of the height. A first filter element 22 for filtering the drawn-in air is arranged following the inlet 20. The filter element 22 is a HEPA filter of the filter class 13. The filtered air is guided via a first conveying element (not visible) towards nozzles 24 arranged around the opening 16. The respective flow direction is illustrated with different arrows in FIG. 1 . The nozzles 24 serve for discharging the filtered air into the interior space 14 of the housing 12. In this case, the nozzles 24 are orientated such that they release air into the interior space 14 and are directed towards hands located in the interior space 14, so that moisture on the hands is conveyed towards the bottom 26 of the interior space 14.
In order to discharge the air—particularly the air coming from the hands—from the interior space 14, the hand dryer 10 has a second conveying element 28 which conveys the air to an outlet 32 through openings 30 arranged in a lower region of the interior space 14. The outlet 32 extends on a side of the hand dryer 10 across a large part of the height.
A second filter element 34, which serves for filtering the air coming from the hands, is disposed between the openings 30 and the outlet 32. The second filter element 34 is a HEPA filter of the filter class 13. In addition, a prefilter 36 is disposed upstream of the second filter element 34. The second filter element 34 and the prefilter 36 are arranged in a filter housing 35. The filter housing 35 is removable via an opening 37 in the housing 12.
The bottom 26 of the housing 12 has a funnel-shaped collection device 38 for the moisture blown off from the hands. The liquid accumulates on the bottom 26 of the housing 12 and can be discharged from there. For this purpose, the collection device 38 is connected at its lower post point to a collection container 42 via a connection 40. A filter 44, which filters bacteria and/or viruses from the water coming off the hands, is arranged between the collection device 38 and the collection container 42. For emptying, the collection container 42 has a valve 43 which can be opened and closed as required.
Another embodiment of a hand dryer 10 is shown in connection with FIGS. 2 and 3 , wherein, for explaining the second embodiment, the same reference numerals as in the description of the first embodiment are used for identical or at least functionally identical components.
A second embodiment of the hand dryer 10 is shown in FIGS. 2 and 3 . The hand dryer 10 has a pot-shaped housing 12 with an interior space 14 and, in this case, two openings 16 for inserting the hands (see FIG. 2 ). One hand can be inserted into the housing 12 through, in each case, one opening 16.
The hand dryer 10 has a first conveying element 46 in the form of a motor-powered fan, by means of which air is drawn in from the environment via an inlet 20 and conveyed in the housing 12 and to the interior space 14. Here, the interior space 14 has a slit-like configuration, and nozzles 24 extending across the sides are arranged on the opposing long sides, so that a flow is directed towards the hands from two sides. For this purpose, the air is guided via a y-shaped connection pipe 48, which extends from the first conveying element 46 to the nozzles 24 (as is apparent from a synopsis of FIGS. 2 and 3 ). In this case, the connection pipe 48 constitutes a direct connection between the first conveying element 46 and the respective nozzle 24 in order to obtain as laminar a flow as possible. A first filter element 22, a HEPA filter of the filter class 13, is arranged between the inlet 20 and the first conveying element 46. The first filter element 22 is arranged in a housing 50, and is replaceable. The nozzle 24 is arranged on the edge of the opening 16 and blows the drawn-in air, towards the bottom 26 of the interior space 14, onto the hands to be dried.
In a lower region of the interior space 14, one opening 30 (not visible), respectively, is formed on the opposing long sides of the interior space 14, via which air is extracted from the interior space 14. For this purpose, the hand dryer 10 has a second conveying element 28, via which the air is conveyed from the respective opening 30 to an outlet 32. The openings 30 are followed in each case by connection pipes 52 (also see the synopsis of FIGS. 2 and 3 ), which first lead to a second filter element 34 in a second filter housing 54, wherein the second filter element 34 serves for filtering the air extracted from the interior space 14.
The bottom 26 of the interior space 14 has a funnel-shaped configuration and serves as a collection device 38 for liquid blown off from the hands. The liquid is discharged through an opening in the bottom 26 of the interior space 14 via a pipe 40 to a collection container 42. The collection container 42 for the liquid is replaceable.
Moreover, the hand dryer 10 comprises a control system 56. The control system 56 is functionally connected to sensors 58 (see FIG. 2 ), by means of which the insertion of hands into the housing 12 and their removal therefrom is detected. If the insertion of hands is detected, then the start-up of the first conveying element 46 and the second conveying element 28 is prompted by means of the control system 56. In addition, a start-up the second conveying element 28 and, if necessary, of the first conveying element 46 can be prompted with the control system 56 even independently of a signal of the sensors 58, in order to filter the ambient air in an interim period.
The housing 12 of the hand dryer 10 has a door (not shown), via which the first filter element 22, the second filter element 34 and the water container 42 can be removed.

Claims

What is claimed is:

1. A hand dryer, comprising:

a pot housing 41 with an interior space with an opening for body parts to be dried;

a first filter element for filtering drawn in air,

at least one nozzle for discharging the filtered air into the interior space of the housing,

a second filter element for filtering the air fed by the nozzle into the interior space 44 of the housing, and

an outlet for discharging the air filtered by the second filter element from the housing.

2. The hand dryer according to claim 1,

wherein

the first filter element and/or the second filter element is a HEPA filter.

3. The hand dryer according to claim 1,

wherein

the at least one nozzle for discharging the filtered air into the interior space is arranged in the region of the opening and directed towards the interior space.

4. The hand dryer according to claim 1,

further comprising

a first conveying element for drawing in air from the environment and for conveying the air into the interior space of the housing, and/or a second conveying element for extracting the air located in the interior space and for discharging on the housing.

5. The hand dryer according to claim 4,

wherein

the first conveying element and the second conveying element can be operated independently of each other.

6. The hand dryer according to claim 1,

wherein

the first filter element and/or the second filter element are replaceable.

7. The hand dryer according to claim 1,

wherein

a collection device for liquid is arranged or formed in the interior space of the housing.

8. The hand dryer according to claim 1,

further comprising a filter for cleaning the collected liquid.

9. The hand dryer according to claim 1,

wherein the collection device is connected to a collection container.

10. The hand dryer according to claim 1,

wherein the housing has, at least partially, an antibacterial and/or antiviral coating.

11. A method for operating a hand dryer having a pot housing with an interior space with an opening for body parts to be dried, a first filter element for filtering drawn in air, at least one nozzle for discharging the filtered air into the interior space of the housing, a second filter element for filtering the air fed by the nozzle into the interior space of the housing, an outlet for discharging the air filtered by the second filter element from the housing, wherein the hand dryer has a first conveying element and a second conveying element that can be operated independently of each other, and wherein the first conveying element and the second conveying element are switched on in case of a detection of hands in the interior space, and wherein the first conveying element and/or the second conveying element are switched on for a defined time interval during a period in which no hands are disposed in the interior space.