JPH0420335Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a dryer, and particularly to a dryer equipped with a safety device that shuts down the device when an abnormally high temperature is detected.

[Conventional technology]

Conventionally, this type of dryer has generally been equipped with one temperature fuse near the heater as a safety device, and when the temperature of the device rises abnormally, the fuse is blown to shut down the device.

[Problem that the invention attempts to solve]

However, with dryers, simply changing the blowing direction of hot air can cause a significant change in the air flow inside the case, causing uneven temperature distribution and causing the area around the detection element to become abnormally hot, leading to the risk of false detection. Ta.

Furthermore, an airflow narrowing nozzle is often attached to the tip of a normal dryer and used as an attachment, or used as a hair blower or hairbrush. Significant fluctuations in flow rate are unavoidable, and if the set temperature of the safety device is low, it may malfunction.
On the other hand, if it was too high, it would no longer function as a safety device, making it difficult to determine the setting conditions.

The present invention was developed in view of the above-mentioned problems, and is designed to prevent the malfunction of the safety device as much as possible in dryers that are normally used with relatively large fluctuations in the amount of air flowing out from the outlet. On the other hand,
The purpose is to provide a dryer in which a safety device is reliably activated in case of equipment abnormality.

[Means for solving problems]

FIG. 1 shows an outline of the present invention, in which a heat generating part 2 is disposed approximately in the center of a main body case 1, a blower part 20 is provided close to one side of the heat generating part 2, and an air outlet 5 is provided on the other side. As a result, air is sent from the blowing section 20 toward the heat generating section 2, and the air flow 21 is heated and discharged from the outlet 5 to the outside.

In the present invention, the means for detecting temperature is composed of a first temperature detecting element 26 and a second temperature detecting element 27 whose set temperature is higher than that of the first temperature detecting element 26. Furthermore,
The first temperature detection element 26 is disposed on the upstream side of the heat generating part 2, and the second temperature detection element 27 is disposed on the downstream side, and the blowing part 20 is energized by detecting the set temperature of the second temperature detection element 27. is stopped, and when the set temperature is detected by the first temperature detection element 26, the supply of electricity to the blower section 20 and the heat generating section 2 is stopped.

[Function] In the above-described configuration, when the air blowing to the heat generating section 2 stops or the air volume decreases due to an abnormality on the side of the blowing section 20, such as when the rotation of the motor of the blowing section 20 is locked, the first The temperature around the temperature detection element 26 rises rapidly. here,
Since the set temperature on the first temperature detection element 26 side is set lower than that on the second temperature detection element 27 side, the first temperature detection element 26 detects the set temperature and the air blower 20
Both the heat generating section 2 and the heat generating section 2 are stopped, and an abnormality in the air blowing section 20 is dealt with.

On the other hand, if the air blower 20 is operating normally, but the air volume decreases because the air outlet 5 is blocked by hair, etc., the first temperature detection element 2 is detected from the air blower 20 side.
6, the temperature rise on the upstream side of the heat generating section 2 is suppressed to a relatively small value, and the first temperature detection element 26 does not detect the set temperature. At this time, due to the decrease in the amount of air flowing out from the air outlet 5, the heat generating part 2 becomes slightly overheated, and the temperature rise on the downstream side becomes large. Therefore, the second temperature detection element 27 side does not immediately detect the set temperature, and when the hair is untied and the air outlet 5 is opened, the normal operating state with the normal air temperature is restored.

However, if the above-described reduced air volume continues, the temperature on the downstream side of the heat generating section 2 exceeds the set temperature of the second temperature detection element 27, and the element 27 detects the set temperature and stops the blowing section 20. Force the airflow to go to zero. Such a blower section 20
As the temperature on the upstream side of the heat generating part 2 increases at an accelerating rate due to the stoppage of the heat generating part 2, the first temperature detection element 26 immediately detects the set temperature, and also stops energizing the heat generating part 2, thereby preventing an abnormal temperature rise. This prevents damage from occurring.

〔Example〕

Although FIGS. 2 to 5 show an example of the present invention applied to a hair dryer, the present invention is not limited thereto, and can of course be applied to various types of hair dryers that blow hot air to dry the hair.

The main body case 1 of the dryer is a half-split left and right case 1a made of cylindrical plastic that is elongated in the front and back direction.
1b are matched and combined. Main case 1
Almost the rear half in the front and back direction is the grip part that the user grasps, and inside the case of this grip part,
A motor 3 and an axial fan 4 of an air blower 20 are arranged in front and behind each other, and a suction port 6 is provided at the rear end of the main case 1 from which a power cord 7 protrudes.

A heat generating part 2 is arranged in front of a motor 3 inside the main body case 1 at approximately the center in the front-rear direction. The fan 4, the motor 3, and the heat generating part 2 are all arranged along the axis P of the main body case 1. Heat generating part 2
In this method, a horizontal substrate 8 and a vertical substrate 9 having insulating properties are arranged in a cross shape orthogonal to each other, and a heater wire 1 is connected to this.
0 and the outer periphery of the heater wire 10 is covered with a metal heat shield cylinder 11.

An air outlet 5 is formed on the lower surface side of almost the front half of the main body case 1 over almost the entire length in the front and rear direction,
An outlet grille 13 having an arcuate cross section and having a large number of ventilation holes 12 is fixed to the outlet 5, and a brush 14 is removably attached to the outside of the rill 13 of the outlet 5. A brush stand 14a having an arcuate cross section of the brush 14 is provided with a row of ventilation holes 15 communicating with the ventilation holes 12.

The heat shield cylinder 11 has a top wall 11a sloped downward toward the front, and a vertical front wall 11b.
is arranged near the front end inside the air outlet 5, and a bottom opening formed in the bottom wall faces the air outlet 5. Therefore, the wind sucked in from the suction port 6 by the fan 4 flows into the heat shield cylinder 11,
After being heated by the heat generating portion 2, the air hits the front wall 11b, changes its flow in a direction perpendicular to the axis P, and is blown out from the air outlet 5.

The vertical substrate 9 of the heat generating part 2 is the front wall 1 of the heat shield cylinder 11
1b, the extended front end of the vertical substrate 9 is used as a left and right partition wall material, and the internal space of the air outlet 5 is divided into left and right halves by this partition wall material.

In this case, the left and right air currents will not mix in the air outlet 5 due to the presence of the left and right partition wall materials, and air will flow from the ventilation holes 12 and 15 arranged in an arc shape in the air outlet 5 in the left and right direction. The air will blow out at a uniform temperature and air volume.

On the other hand, the front end of the horizontal base plate 8 is set to have a length that is located halfway forward of the central position of the air outlet 5 in the longitudinal direction, and is partitioned within the air outlet 5 by the horizontal base plate 8. Upper and lower airflow 21
The air is blown out at an even temperature as much as possible in the front-back direction so that abnormal heating does not occur in the vicinity of the center of the front-back direction of the blow-off port 5.

FIG. 5 is an electric circuit diagram used in the present invention, in which the blower section 20 of the heat generating section 2 can be connected in parallel to a power source via a switch 22 provided on the upper part of the main body case 1.

The switch 22 is of a sliding type, and when it is moved back from the central off position, the first contact 23 closes.
When the motor 3 of the blower section 20 connected to the contact point 23 is energized and reversely moved forward, both the first and second contacts 23 and 23a close, and the motor 3 is connected not only to the blower section 20 but also to the second contact point 23a. The heat generating section 2 is also energized.

The blower section 20 has the motor 3 connected via a filter 33 to the output side of a diode bridge 24 that rectifies the commercial AC voltage, and the motor 3 is driven by the motor drive voltage that has been full-wave rectified by the diode bridge 24. The fan 4 attached to the rotating shaft is rotated at high speed to blow air to the heat generating part 2.

The heat generating section 2 consists of a coiled heater wire 10 and a temperature control means 25 such as a thermostat disposed at the center of the heater wire 10.
5 is intermittent at the set temperature, the heater wire 10
The temperature of the airflow 21 is controlled by regulating the timing of energization.

In this embodiment, a first temperature detecting element 26 is further interposed in the common circuit between the heat generating part 2 and the blowing part 20, and a second temperature detecting element 27 and a motor driving part are connected in series with the diode bridge 24 of the blowing part 20. A voltage control resistor 28 is connected.

The first and second temperature detection elements 26 and 27 both use temperature fuses and are installed between the horizontal substrate 8 and the vertical substrate 9 as shown in FIGS. 2 and 3. 26
is arranged between the motor 3 and the heater wire 10, and a second temperature detection element 27 is arranged between the heater wire 10 and the air outlet 5. The first temperature detection element 26 has a set temperature of, for example, about 190°C, while the second temperature detection element 27
The set temperature is set to about 240° C., which is higher than that, and both elements 26 and 27 are separated into upper and lower air channels 29a and 29b formed by cross-shaped substrates 8 and 9 and a heat shield tube 11. In addition to establishing
The temperature detection element 2 is arranged so as to cross the flow path 29.
6 and 27 are arranged.

As shown in FIG. 4, the motor drive voltage control resistor 28 is a low-resistance substrate type in which a thin resistance wire 31 is wound many times around an insulating substrate 30 with a through-hole cutout 32 in the center. The winding resistance is such that the resistance is close to the downstream side of the heater wire 10 in the air flow path 29 and there is a sufficient spatial distance to allow a portion of the air flow 21 to flow over the horizontal substrate 8. By horizontally attaching the eyelet-shaped terminals 35 for leading out both ends of the wire 31 as legs, the air flow 21 is not disturbed.
In addition, it is brought into close contact with the air flow 21 over a wide area, so that it can be heated in response to changes in the temperature of the air flow 21.

With the above configuration, when the rotation of the motor 3 is locked due to hair getting entangled in the fan 4 and the air supply stops, the heater wire 10 overheats and the ambient temperature of the heat generating part 2 uniformly increases, and the temperature of the motor 3 increases. The temperature also rises in the motor 3 due to the lock. Here, the first and second temperature detection elements 26 and 27 have different detection set temperatures, and since the first temperature detection element 26 is arranged at an intermediate position between the motor 3 and the heat generating part 2, it is heated by both. First, the temperature fuse of the first temperature detection element 26, which has a low set temperature, is fused and the power supply to the heat generating part 2 and the ventilation part 20 is stopped, thereby preventing damage to the equipment, and
When the temperature detection element 26 is fused, an abnormality in the blower section 20 is displayed.

After the rotation of fan 4 is locked, the first
Although it is inevitable that there will be a time delay until the temperature detection element 26 operates and the motor 3 is stopped, there is a risk that the motor 3 will be damaged if such an overloaded state is left as it is. In this embodiment, by arranging the resistor 28 in the vicinity of the heat generating part 2 and closer to the downstream side where the temperature rise is the greatest, the resistance value of the resistor 28 increases as the temperature rises, and the input of the diode bridge 24 increasing the amount of voltage drop on the side, and as a result, reducing the voltage applied to the motor 3 to reduce the output torque of the motor 3 as much as possible,
Damage to the motor 3 is prevented.

Next, although the blower section 20 is operating normally, the air flow is
When the temperature rises, the temperature rises more sharply on the downstream side than on the upstream side of the heat generating part 2, and the second temperature detection element 27 melts first, stopping the motor 3 and indicating an abnormality in the equipment. When the air blowing is stopped, the temperature on the first temperature detection element 26 side also rises, and the element 26 is activated to stop the entire device. At this time, since the second temperature detection element 27 is fused, the heat generating part 2
The abnormality will be displayed.

[Effect of idea]

As described above, the present invention provides a safety device by arranging the first temperature detecting element 26 and the second temperature detecting element 27 separately on the upstream and downstream sides of the heat generating section 2, thereby detecting temperatures over a wide range. Abnormalities can be detected reliably.

Furthermore, the set temperature of the second temperature detection element 27 is set to the first temperature.
Since the temperature is set higher than the set temperature of the temperature detection element 26 and the power supply to the blower section 20 is stopped in conjunction with the detection operation of the second temperature detection element 27, fluctuations in the amount of air flowing out from the air outlet 5 can be prevented. This has the advantage of being able to prevent malfunction as a safety device even when the device is being used intensively, and to ensure safety by shutting off the current as soon as possible in the event of a truly abnormally high temperature. .

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an outline of the present invention. Figures 2 to 5 show an example of the present invention applied to a hair dryer, and Figure 2 is a vertical side view;
3 is a sectional view taken along the line -- in FIG. 2, FIG. 4 is a perspective view of the main parts, and FIG. 5 is an electric circuit diagram. 2... Heat generating part, 3... Motor, 20... Air blower, 26... First temperature detection element, 27... Second temperature detection element.

Claims (1)

[Claims for Utility Model Registration] 1. A heat generating unit 2; a blowing unit 20 that blows air toward the heat generating unit 2 to form an air flow 21 at a predetermined temperature; 1 temperature detection element 26, and a second temperature detection element 27 that is disposed downstream of the heat generating part 2 and has a higher set temperature than the first temperature detection element 26, and the set temperature of the second temperature detection element 27 described above. Energization to the air blowing unit 20 can be stopped in conjunction with the detection operation of the air blowing unit 20 and the heat generating unit 2 in conjunction with the detection operation of the set temperature in the first temperature detection element 26 described above. A dryer characterized by: 2 The heat generating section 2 described above has heater wires 1 around a horizontal board 8 and a vertical board 9 assembled in a cross shape.
0, and further cover the substrates 8 and 9 with a heat shield cylinder 11,
A plurality of air channels 29a, 29b are formed between the substrates 8, 9 and the heat shield tube 11, and the first temperature detection element 26 and second temperature detection element 27 described above are connected to the air channels 29a, 29b. The dryer according to claim 1 of the utility model registration claim, wherein the dryer is arranged in different ways. 3. The dryer according to claim 1 or 2, wherein the first temperature detection element 26 and the second temperature detection element 27 described above are temperature fuses that melt when the set temperature is exceeded.