CN115867168A

CN115867168A - Hair drier

Info

Publication number: CN115867168A
Application number: CN202180048645.0A
Authority: CN
Inventors: M·J·勒莱维尔德
Original assignee: Koninklijke Philips NV
Current assignee: Koninklijke Philips NV
Priority date: 2020-07-07
Filing date: 2021-07-05
Publication date: 2023-03-28
Also published as: EP4178394A1; PL4178394T3; US20230255335A1; WO2022008408A1; EP4178394B1

Abstract

A hair dryer comprises a fan (F) for generating an air flow, and a drying chamber (HC) having a hair entry opening (I1), through which hair can be guided into the hair entry opening (I1). The cross-section of the drying chamber (HC) has a first dimension in a first direction which is at least 5 times larger than a second dimension in a second direction perpendicular to the first direction, wherein the first and second directions are perpendicular to the direction of the gas flow. The drying chamber (HC) may be folded such that the drying chamber has a U-turn in the direction of the airflow. The first area of the cross-section of the drying chamber (HC) at the U-turn may be smaller than the second area of the cross-section located in the middle of the hair entrance (I1) and the U-turn. The hair entrance (I1) of the drying chamber (HC) may be shaped to follow the contour of the user's head. The blower may be arranged to heat the hair from multiple sides. The walls of the drying chamber (HC) may be provided with hydrophilic or water-absorbing or water surface tension reducing material. The water-absorbing material can be regenerated by hot air. The drying chamber (HC) may be openable, whereby the drying chamber can be cleaned. The blower may have a sensor (MS) for sensing the temperature and/or humidity of the airflow at the air outlet of the blower, and a portion of the airflow may be recirculated based on the output of the sensor (MS). The blower may have a nozzle to direct heated air towards the scalp of the user. The walls of the drying chamber (HC) may be shaped to shape the hair and/or to increase the contact area with the hair.

Description

Hair drier

Background

US4118874A discloses a hair dryer having an inner duct and an outer duct connected at one end to a centrifugal fan and at the other end to a hood. The fan draws air through the inner duct and blows it through the outer duct towards the shroud. A grill for supporting the long hairs is located in the inner duct so that air drawn toward the fan is drawn through any long hairs on the grill.

KR20160024677A discloses a hair dryer for long hair which accommodates and dries long hair isolated from the outside to maximize drying efficiency. This hair dryer includes: a housing having a handle formed on an outer surface of one side and a hair accommodating space formed with a predetermined depth, wherein hair can be introduced through an opening at an upper portion to be accommodated; a blower installed at a lower portion of the housing for sucking and blowing external air into the hair accommodating space; a blowing induction portion that blows air blown toward an inner wall surface of the housing by the blower toward an outer periphery of the hair accommodated in the hair accommodating space; and a heating device installed at a side of the blower where the air is discharged to heat the blown air.

US2016150864A1 discloses a hair grooming system comprising a vacuum canister, a hose and a handheld unit. A hose is secured to and in fluid communication with the vacuum tank and the handheld unit. The hand-held unit includes a vacuum chamber. The mechanism for generating a vacuum is located in a vacuum tank, and the vacuum is communicated with the vacuum chamber through a hose. The system may further comprise a heating element and a fan arranged to heat air and move the air into the vacuum chamber. In one embodiment disclosed herein, a method of combing hair comprises the steps of: placing a portion of the hair in a vacuum chamber; drawing a vacuum to remove excess water from the hair; and applying heated air to the section of hair.

Disclosure of Invention

It is, inter alia, an object of the invention to provide an improved hair dryer. The invention is defined by the independent claims. Advantageous embodiments are defined in the dependent claims.

The cross-section of the drying chamber has a first dimension in a first direction that is at least 5 times larger than a second dimension in a second direction perpendicular to the first direction, wherein the first direction and the second direction are perpendicular to the direction of the gas flow in the drying chamber. Thus, the drying chamber is oval or even flat. Compared to a drying chamber with a circular cross-section, the advantage is obtained that the hair is spread over the width of the drying chamber, so that the hair is dried more evenly. With a circular drying chamber, the hairs in the middle of the hair bundle will remain moist, while the hairs outside the hair bundle will be dry, and if the settings are adjusted such that the hairs in the middle are also sufficiently dry, the hairs outside the hair bundle will be exposed to too much heat, which will damage the hairs.

Preferably, the first dimension is at least 10 times greater than the second dimension.

A compact blower design is obtained if the drying chamber is folded, the drying chamber having a U-turn in the direction of the air flow.

If the first area of the cross-section of the drying chamber at the U-turn is smaller than the second area of the cross-section in the middle of the hair-entry opening and the U-turn, the air velocity is locally increased, which facilitates the entry of hairs into the device. For smaller cross sections, it is also possible to increase the radius of the turn, which in turn makes it easier for the hair to form a U-turn without deformation or undesired curling.

A more satisfactory hair drying experience is obtained if the blower is arranged to heat the hair from multiple sides.

The drying speed is also increased if the walls of the drying chamber are provided with a material that is hydrophilic or water-absorbing or that reduces the surface tension of water.

If the water absorbing material can be regenerated by hot air, the material can be used several times.

The drying chamber can be cleaned if it is openable.

If the blower has a sensor for sensing the temperature and/or humidity of the airflow at the air outlet of the blower and part of the airflow is recirculated based on the output of the sensor, the airflow can be controlled to obtain the best results in terms of speed and hair feel and can be achieved with less heater power.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

Drawings

Figure 1 shows a cross-section of an embodiment of a hair dryer according to the present invention.

Figure 2 shows another view of a hair dryer according to the present invention.

Detailed Description

As best shown in fig. 2, the inlet I1 for hair and cold air is wide, similar to a letter box. The wide entrance I1 of the drying chamber spreads the hair evenly, preventing the hair in the middle of a lock of hair from drying poorly. Based on the coanda effect, a circular curve at the hair entrance I1 bends the hair into the device. In a preferred embodiment, the hair entry I1 has dimensions of 5mm by 50mm to 20mm by 250mm. In a practical example, the inlet I1 is 10mm by 120mm.

Although the hair-entry apertures I1 may be straight, in a preferred embodiment the hair-entry apertures I1 are shaped to follow the contours of the user's head to allow more hair to enter the drying chamber. The hair entry I1 may thus be curved. In an alternative embodiment, the hair entry I1 may be V-shaped.

In the embodiment shown, the drying chamber is formed by a folded hair channel HC, in which the hairs will enter (downwards), then turn U-around a first circular edge E1 upwards, and then turn U-around a second circular edge E2 downwards. In this way, a 60cm long hair path required by customers with long hair can fit into a compact device that is only about 20cm high. At the edges E1 and E2, the cross-sectional area may be smaller than the cross-sectional area between the edges at rest, thereby locally increasing the air velocity to help pull the hair through the U-turn and ensure that the U-turn is more rounded, which also helps to allow the hair to pass through the U-turn in the hair channel HC. In a less complex embodiment, the drying chamber has only one U-turn.

The inner wall of the drying chamber may be provided with dimples, since the air flow is confined and the dimples may reduce the resistance. The dimples also help to improve heat exchange.

Preferably, the walls of the drying chamber HC are shaped to shape the hair and/or to increase the contact area with the hair. The hair channel 11C may comprise ribs for spreading or even styling hair, and may comprise swirl ribs that can be set to create a curling effect. Such ribs increase the contact area with the hair if the walls of the hair passage are hot, thereby accelerating the drying process.

At the end of the drying chamber, a filter FT prevents hairs from entering the fan F. The filter FT is preferably removable to allow cleaning.

The suction fan F can be set to flow rate, strong and weak. The fan F should be able to handle a minimum amount of water/moisture. The fan F can generate an air flow of between 5l/s and 40l/s, preferably between about 18l/s and 20 l/s; fans used in some vacuum cleaners may be suitable for this purpose. Preferably, a single motor/fan unit is used to generate a suction force that not only pulls the hairs into the hair channel HC, but also pulls air into the hair channel HC through or along the heater HT.

In the embodiment shown, hot air is supplied to hair that has entered the blower from only one side (i.e., from the right side in the figure). In another embodiment, hot air is provided to the hair from both the left and right sides.

In the shown embodiment, the heater HT is shown on the right side of the folded hair channel HC. In other embodiments, the heater HT is placed elsewhere, for example at the bottom, or before or after the folded hair channel, as shown in fig. 1, from the point of view of the person viewing fig. 1.

Alternatively and/or additionally, for the suction fan F to suck hairs into the hair passage at the end of the hair passage HC, a fan may be provided in the separate passage in which the heater HT is placed, in order to generate an air flow in the hair passage HC that guides the hairs into the hair passage.

As shown in our co-pending application EP 20173773.1 (attorney docket No. 2020PF 00319), the hair passage HC may have multiple hot air inlets along its trajectory to ensure a more even distribution of heat over the length of the hair, and thus a more even drying rate.

After the fan F there is an outlet O for humid air. If the hair dryer is provided with a heater HT, the outlet air is hot and can be used to dry the scalp. For this purpose, the outlet air should be directed towards the scalp.

Just before the filter FT, or between the filter FT and the fan F, there may be a sensor MS to measure the moisture and/or temperature, which is related to the dryness of the hair. Depending on the reading from sensor MS, some of the outlet air from fan F may be redirected towards heater HT by valve V2 to ensure that the air flows along heater HT. This recirculation can save energy (since the heat in the outlet air is not wasted but is recycled), which is particularly important for battery operated blowers. However, the air flow should allow sufficient cooling of the heater HT. However, the recirculated air may have too much moisture to ensure that the hair is dried in a satisfactory manner, so that if the sensor MS indicates that the air contains too much moisture, the air is not recirculated or is only recirculated to a limited extent by appropriately controlling the valve V2. Based on the reading from the humidity sensor MS, the blower may indicate that the hair has been sufficiently dried, for example by a beep.

If the heater HT is of a type providing heated air to the hair, the outlet of the air passage in which the heater HT is located is arranged at the beginning of the hair passage HC near the hair entry I1. The air flow is balanced in such a way that enough air passes through the heater to cool it and provide hot air to the hair. For example, approximately 50% of the air flow in the hair passage is through the hair entry openings and approximately 50% of the air flow in the hair passage is from the passage or passages in which the heater HT is located. Once the hair closes the hair entry opening I1, the hot air ratio will increase. To ensure that a sufficient amount of hot air is applied to the hair, a mechanism may be provided to narrow the inlet I1 once the hair has entered the blower, so that less cold air can enter the blower through the inlet I1. The air channel in which the heater HT is located may have its own cold air inlet I2 in case there is no recirculation or not enough recirculation to ensure a sufficiently large air flow to cool the heater HT and to provide a sufficient amount of hot air to the hairs.

The heater HT may be controlled by a temperature switch. The temperature in the hair passage 11C is preferably about 70-100 ℃. The heater HT may be a conventional (coil/ceramic) heater. The heater HT may have a power of between 1000W and 2500W, for example a 1600W or 2100W heater, as used in conventional blowers.

If the heater HT is element-based, it can be placed along the wall of the hair channel (e.g., PTC heater/film heater). Also, the surface may have dimples to improve heat exchange. When all the heat flows along the hair, the capacity of the heater can be smaller. The lower heater wattage allows for cordless, i.e., battery operated devices, because of the better efficiency.

If the heater HT is based on light radiation, the entire hair channel HC can be made transparent/mirrored to allow all light to pass through and hit the hair multiple times. As in our co-pending application WO2019/048357 (attorney docket No.: 2017PF 02405), preferably, the heat generated by the LED unit is reused to heat the hair, e.g. by an air flow that has passed the LED unit or its cooling body.

If the heater HT is turned off and cool, as indicated by temperature sensor TS1, valve V1 at the outlet of the hot air channel can be closed to ensure increased suction through inlet I.

There may be an IR sensor inside to measure the temperature of the hair. Other sensors may be added, such as a camera that allows the settings of the fan F and/or the heater HT and/or any ionizers to be adjusted by the fan F and/or the heater HT and/or any based on an analysis (possibly involving artificial intelligence) of the images taken by the camera.

If the blower is battery powered, the battery may be cooled by the air in the hair passage HC.

The hairdryer may be connected with IoT, e.g. the device may have a bluetooth connection with a smartphone with app, so that the device may be controlled by the smartphone, which makes it particularly interesting when using the hairdryer if the hairdryer is a desktop device placed on a table on the back of the user, so that any control on the hairdryer cannot be reached. The device may have a UI. The blower may be hand-held, with or without a power cord. The device may be placed on a table and at an angle.

The inner walls of the hair channel HC are preferably provided with a covering of a water absorbing material for absorbing water and/or a material for breaking/reducing the surface tension of water droplets to increase the drying rate. Preferably, the water absorbing material is capable of being regenerated by passing hot air through the hair passages in the absence of hair.

Alternatively, the hair may be dried without the application of hot air, i.e. by using ultrasound, for example as described in EP 3416521B1 (attorney docket: 2016PF 00205).

When the hair is pulled out, hair health can be measured by measuring friction in the manner shown in our co-pending application WO2019/057575 (attorney docket No.: 2017PF 02274).

In one embodiment, the blower has a nozzle to direct hot air (e.g., outlet air) toward the scalp of the user to dry the scalp while the hair is being dried, which provides a spa-like experience.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps other than those listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The measures described in mutually different dependent claims can advantageously be used in combination.

Claims

1. A hair dryer, comprising:

a fan (F) for generating an air flow; and

a drying chamber (HC) having a hair inlet (I1) into which hair can be guided by the air flow;

wherein a cross-section of the drying chamber (HC) has a first dimension in a first direction which is at least 5 times larger than a second dimension in a second direction, which is perpendicular to the first direction, wherein both the first and the second direction are perpendicular to the direction of the gas flow.

2. The blower of claim 1 wherein said first dimension is at least 10 times greater than said second dimension.

3. The blower according to any one of the preceding claims, wherein the drying chamber (HC) is folded such that it has a U-turn in the direction of the air flow.

4. The hair dryer of claim 3, wherein a first area of a cross section of said drying chamber (HC) at said U-turn is smaller than a second area of a cross section located in the middle of said hair inlet (I1) and said U-turn.

5. Hair dryer according to any one of the preceding claims, wherein said hair inlet (I1) of said drying chamber (HC) is shaped so as to follow the contour of the user's head.

6. The hair dryer of any preceding claim, wherein the hair dryer is arranged for heating hair from multiple sides.

7. The hair dryer of any preceding claim, wherein the walls of said drying chamber (HC) are provided with a material that is hydrophilic or absorbs or reduces the surface tension of water.

8. The hair dryer of claim 7, wherein said water absorbent material is capable of being regenerated by hot air.

9. Hair dryer according to any one of the preceding claims, wherein said drying chamber (HC) is openable so that it can be cleaned.

10. The blower of any preceding claim, wherein the blower has a sensor (MS) for sensing the temperature and/or humidity of the airflow at an air outlet of the blower, and wherein part of the airflow is recirculated based on the output of the sensor.

11. A hair dryer according to any preceding claim wherein said hair dryer has a nozzle to direct heated air towards the scalp of a user.

12. Hair dryer according to any one of the preceding claims, wherein the walls of the drying chamber (HC) are shaped to style the hair and/or to increase the contact area with the hair.