JPH0523209A - Hair dryer - Google Patents

Abstract

PURPOSE:To restrain increase in the temperature and volume of air even though a hair dryer is moved or combing is performed, so as to prevent hairs or a hand from being overheated, by causing a control means to hold the temperature and volume of air when the temperature of hairs lowers. CONSTITUTION:There are provided a fan 3 driven by a motor 2, a heater 4 for heating air blown from the fan 3, and a contactless temperature sensor 1 such as a thermopile for detecting a radiation energy emitted from hairs and converting the detected energy into an electric signal so as to detect a temperature of the hairs in a contactless condition. Further, there are provided a control circuit 5 for phase-controlling the output of the heater 4 in accordance with a temperature of the hair detected by the contactless temperature sensor 1, and a holding circuit 6 for temporarily holding a power control signal to the heater 4 when a value obtained by differentiating an electrical signal delivered from the sensor 1 is negative, that is, when the detected temperature of the hairs is lowered. When the temperature of the hairs is lowered by combing, the holding circuit 6 holds the output of the heater at a value which is obtained when the lowering of the temperature is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hair dryer, and more particularly to a hair dryer which controls the air temperature or the air volume according to the temperature of hair.

[0002]

2. Description of the Related Art In recent years, hair dryers are equipped with a monitoring means for monitoring the air temperature so that the air temperature does not become too high. The temperature rises more than necessary, causing hair damage. For this purpose, a measuring means for measuring the temperature of the hair in a non-contact manner, and a control means for controlling the air temperature or the air volume according to the height of the hair temperature detected by this measuring means are provided.
For example, Japanese Patent Application Laid-Open No. 57-168605 discloses a hair dryer that lowers the air temperature or air volume when the hair temperature is high and raises the air temperature or air volume when the hair temperature is low.

[0003]

In this case, there are the following problems. That is, when the hair is dried or habituated by applying warm air to the hair and the hair dryer is moved or a hand comb is performed, the temperature of the hair detected by the measuring means becomes low, so that the air temperature or the air volume is reduced. It may become unnecessarily high and overheat your hair and hands.

Further, since the output control of the heater for adjusting the air temperature is performed by the phase control, the measuring means may pick up noise generated during the phase control and malfunction. The present invention has been made in view of the above points, and an object of the present invention is to provide a hair dryer capable of controlling an appropriate air temperature or air volume.

[0005]

SUMMARY OF THE INVENTION The present invention, therefore, provides a measuring means for measuring the temperature of hair in a non-contact manner, and a control for controlling the air temperature or the air volume according to the level of the hair temperature detected by this measuring means. In a hair dryer equipped with means,
The control means has the first feature in that it holds the air temperature or the air volume with respect to the decrease in the hair temperature, and the control means performs the control by the phase control and the signal from the measuring means. Taking in outside the phase control timing,
Another feature is that it is performed at the time of zero crossing of the power supply.

According to the first feature of the present invention, even if the hair temperature detected by the measuring means is temporarily lowered by moving the hair dryer or performing a hand comb, the wind temperature or The air volume does not increase, and according to another feature, it is possible to avoid the influence of noise generated during the phase control.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the illustrated embodiment. In this hair dryer, as shown in FIG. 1, a fan 3 driven by a motor 2 and a heater 4 for heating air blown by the fan 3 are provided. And a non-contact temperature sensor 1 such as a thermopile that measures the hair temperature in a non-contact manner by detecting radiant energy emitted by the hair and converting it into an electric signal, and the non-contact temperature sensor 1 detects the temperature. When the differential value (temperature change rate) of the electric signal from the control circuit 5 that controls the output of the heater 4 by phase control according to the height of the hair temperature and the non-contact temperature sensor 1, that is, it is detected. A holding circuit 6 for temporarily holding the power control signal of the heater 4 when the hair temperature is lowered is provided.

In this hair dryer, however, when the temperature of the hair rises due to the discharged hot air, the non-contact temperature sensor 1 detects this and the control circuit 5 outputs the output of the heater 4 as shown in FIG. To lower. When the detected hair temperature is lowered by moving the hair dryer or combing the hand, the control circuit 5 tries to increase the output of the heater 4 in response to this decrease, while the holding circuit 6 holds the heater 4 output at the value at the time when the temperature drop is detected.

This holding is performed for a predetermined time, for example, 0.
It may be performed only for 5 seconds, but when the detected hair temperature returns to the temperature before the differential value of the electric signal from the non-contact temperature sensor 1 becomes negative, or the differential value is non-contact. If the holding is released when the differential value of the electric signal from the temperature sensor 1 returns to the differential value before becoming negative, as shown in FIG. 3, a smoother control of the heater 4 can be performed.

FIG. 4 and FIG. 5 show another embodiment. As shown in the figure, the output control of the heater 4 is performed by the phase control through the phase control circuit 7. In the phase control of the heater 4, a hold circuit 8 is arranged between the control circuit 5 and the non-contact temperature sensor 1. While the control is being performed, the output of the non-contact temperature sensor 1 is not sent to the control means as it is, but is sent while holding the immediately preceding value. In this case, it is possible to prevent malfunction due to noise N associated with the phase control.

As shown in FIGS. 6 and 7, the zero-cross detection circuit 10 for detecting the zero-cross of the power source and the temperature from the non-contact temperature sensor 1 are held when the zero-cross detection signal from the zero-cross detection circuit 10 is received. A sample hold circuit 9 may be provided so that the detected temperature signal at the time of zero crossing is transmitted to the control means through the sample hold circuit 9. If it is digital control, A / D conversion is executed at zero cross. Also in this case, the influence of noise accompanying the phase control is not exerted.

[0012]

As described above, in the present invention, the control means controls the measuring means by moving the hair dryer or performing a hand comb in order to maintain the air temperature or the air volume with respect to the decrease in the hair temperature. Even if the detected hair temperature is temporarily lowered, the air temperature or air volume does not increase, and therefore the air temperature or air volume does not become unnecessarily high and overheat the hair or hands. Therefore, the air temperature or the air volume can always be controlled to an appropriate value.

Further, in the case where the control means controls by the phase control, since the signal from the measuring means is fetched outside the phase control timing or at the time of zero cross of the power source, the influence of noise generated during the phase control is affected. It is possible to reliably control the air temperature or the air volume while avoiding the above.

[Brief description of drawings]

FIG. 1 is a block diagram.

FIG. 2 is an operation explanatory diagram.

FIG. 3 is an operation explanatory diagram of another example.

FIG. 4 is a block diagram of another example.

FIG. 5 is an operation explanatory diagram.

FIG. 6 is a block diagram of yet another example.

FIG. 7 is an operation explanatory diagram.

[Explanation of symbols]

1 Non-contact temperature sensor 4 heater 5 control circuit 6 holding circuit

Claims (3)

[Claims] 1. A hair dryer comprising: a measuring means for measuring the temperature of hair in a non-contact manner; and a controlling means for controlling the air temperature or the air volume according to the height of the hair temperature detected by the measuring means. A hair dryer characterized in that the means holds the air temperature or the air volume with respect to the decrease in the hair temperature. 2. A hair dryer comprising: a measuring means for measuring the temperature of hair in a non-contact manner; and a controlling means for controlling the air temperature or the air volume according to the height of the hair temperature detected by the measuring means. The hair dryer is characterized in that the means controls by phase control and the signal from the measuring means is fetched outside the phase control timing. 3. A hair dryer comprising: a measuring means for measuring the temperature of hair in a non-contact manner; and a controlling means for controlling the air temperature or the air volume according to the height of the hair temperature detected by the measuring means. The hair dryer is characterized in that the means controls by phase control and the signal from the measuring means is taken in at the time of zero cross of the power source.