JPH08261560A - Electrical hot air heater - Google Patents

Abstract

PURPOSE: To provide an electrical hot air heater for blowing hot air with heat generated at a ceramic heater in which an electrical power amount for a PIG heater can be controlled while an amount of hot air being kept as it is by a method wherein the ceramic heater is provided with an electrical energization rate control means for controlling an electrical energization rate. CONSTITUTION: When a power supply switch at an operating part 21 is turned on, a main control part 20 generates an operating instruction against a fan driving part 16 and an electrical energization control part 23. With such an arrangement as above, a fan motor 14 is driven under a specified number of rotation and then a specified amount of air is fed to two PTC heaters 1, 2 under a rotation of a blower fan 15. At this time, a set temperature is compared with an actual room temperature at an electrical energization control part 23 and then an electrical energization rate control is carried out for the PIC heaters 1, 2 in response to a difference in both temperatures. That is, a zero- cross point is detected in response to an AC wave-form at the power supply part 24 to cause relays 10, 11 to be alternatively energized or de-energized, wherein electrical power of half-wave displaced by 180 deg. in its phase is supplied to the PIC heaters 1, 2 so as to generate heat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric air blower for blowing heat of a ceramic heater (hereinafter referred to as PTC heater) as warm air.

[0002]

2. Description of the Related Art In such an electric warmer, two PTC heaters 1 and 2 (also referred to as an upper PTC heater 1 and a lower PTC heater 2) are connected in parallel as shown in FIG.
The commercial power source 3 of 0V is connected.

With such a configuration, when performing the heating operation, the sine wave voltage is applied to both ends of the upper and lower two PTC heaters 1 and 2 at the same time when the commercial power source 3 is turned on. To generate heat.

Along with this, the blower fan is driven to drive each PTC.
A constant amount of air is blown to the heaters 1 and 2. As a result, the heat generated in each PTC heater 1 and 2 is blown as warm air.

However, since the energizing method of applying the sinusoidal voltage to both ends of the two PTC heaters 1 and 2 is adopted, the amount of electric power supplied to the PTC heaters 1 and 2 is not controlled. Instead, the amount of electric power to the PTC heaters 1 and 2 cannot be controlled while the amount of warm air is constant.

Therefore, it is difficult to finely adjust the temperature of the warm air. Therefore, for example, when the set temperature is 20 ° C. in the automatic operation, the temperature of the hot air cannot be finely adjusted, so that the room temperature has large fluctuations near the set temperature as shown in FIG.

[0007]

As described above, the amount of electric power to the two PTC heaters 1 and 2 cannot be controlled while the amount of warm air is constant. Therefore, an object of the present invention is to provide an electric warmer capable of controlling the amount of electric power to the PTC heater while keeping the amount of warm air constant.

[0008]

According to a first aspect of the present invention, there is provided an electric warmer for energizing a ceramic heater and driving a blower fan to blow the heat generated in the ceramic heater as warm air. The electric hot air blower is intended to achieve the above object by including a duty ratio control means for controlling the duty ratio.

According to the second aspect, the plurality of ceramic heaters are energized and the blower fan is driven to blow a constant amount of air to the plurality of ceramic heaters to heat the heat generated in the ceramic heaters. An electric warmer that blows air as a wind, comprising: a duty ratio control unit that controls a duty ratio for at least one ceramic heater among a plurality of ceramic heaters. According to the third aspect of the present invention, the duty ratio control means is an electric warmer that supplies the electric powers of the respective half-wave waveforms that are 180 ° out of phase with each other to the two ceramic heaters.

[0010]

According to the first aspect of the present invention, the energization rate control means controls energization of the ceramic heater, and the heat generated in the ceramic heater at this time is blown as warm air by driving the blowing fan. By performing the duty ratio control on the ceramic heater in this manner, it is possible to control the amount of electric power to the PTC heater while keeping the amount of warm air constant.

According to the second aspect, the energization rate control means controls energization of at least one of the plurality of ceramic heaters, and the heat generated in the ceramic heater at this time is controlled by driving the blower fan. Blow as a wind.

According to the third aspect of the present invention, the energization control for the ceramic heater is performed by supplying the electric powers of the respective half-wave waveforms which are 180 ° out of phase with each other to the two ceramic heaters, respectively. Take control.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an electric warmer. The relay contact 10a of the relay 10 is connected between the upper PTC heater 1 and the commercial power supply 3, the relay contact 11a of the relay 11 is connected between the lower PTC heater 2 and the commercial power supply 3, and the upper PTC is further connected. A relay contact 12 a of the relay 12 is connected between the connection point between the heater 1 and the lower PTC heater 2 and the commercial power supply 3.

In these relays 10 to 12, the relay coils 10b to 12b are energized by the relay drive unit 13,
It is supposed to be de-energized. Here, relay 12
The upper PTC heater 1 and the lower PTC heater 2 are connected in parallel to the commercial power source 3 by closing the relay contact 12a of the above, and the upper PTC heater 1 and the lower PTC heater 2 are opened by opening the relay contact 12a of the relay 12. Are connected in series to the commercial power supply 3.

On the other hand, a blower fan 15 is attached to the rotary shaft of the fan motor 14. This fan motor 14
Is driven to rotate at a constant rotation speed by the fan drive unit 16.

An air passage is formed so that the air blown by the rotation of the air blower fan 15 is sent to the two PTC heaters 1 and 2. Next, the configuration of the control system will be described.

Each command issued from the main controller 20 causes the relay driver 13, the fan driver 16, and the operation unit 2 to operate.
1, the connection switching unit 22, and the energization control unit 23 are integrally controlled.

The power supply unit 24 converts the AC power of the commercial power supply 3 into DC power of a predetermined voltage, and uses this DC power as a drive voltage for the relay drive unit 13, the fan drive unit 16, the operation unit 21, and the connection switching unit. 22 and the energization control unit 23.

The operation unit 21 includes a power switch and an upper PTC.
The heater 1 or the lower PTC heater 2 is provided with a selection switch, a heating temperature setting switch, a room temperature adjustment switch, and the like. The connection switching unit 22 is an upper PTC in the operation unit 21.
When the selection switch of the heater 1 or the lower PTC heater 2 is operated, it has a function of sending the operation content of this selection switch to the relay drive unit 13.

In other words, the connection switching unit 22 has the upper PTC.
If only the heater 1 is selected, each relay 10, 12 is energized, and if only the lower PTC heater 2 is selected, each relay 1 is selected.
The relay drive unit 13 has a function of energizing the first and the second PTC heaters 12 and sending the operation content to energize all the relays 10 to 12 if the two PTC heaters 1 and 2 are selected.

Further, the connection switching section 22 has a function of sending to the relay drive section 13 the operation contents for releasing the energization of the relay 12 if the two PTC heaters 1, 2 are connected in parallel. There is.

The energization control section 23 compares the set temperature of heating with the actual room temperature and controls the energization rate of the two PTC heaters 1 and 2 so that the actual room temperature is maintained at the set temperature. One or both of the relays 10 and 11 are repeatedly energized and de-energized with respect to the relay drive unit 13, and the PTC heaters 1 and 2 are respectively 180
° It has the function of supplying the power of each half-wave waveform with a phase shift.

In this case, the energization control unit 23 has the power supply unit 24.
The zero-cross point is detected from the AC waveform, and either or both of the relays 10 and 11 are repeatedly energized and deenergized based on the zero-cross point to obtain a half-wave waveform power.

Next, the operation of the electric warmer configured as described above will be described. When the power switch is turned on in the operation unit 21, the main control unit 20 causes the fan drive unit 16 to operate.
And an operation command to the energization control unit 23.

In response to this operation command, the fan drive unit 16
Drives the fan motor 14 at a constant rotation speed, and the blower fan 15 rotates in response to this. This blower fan 1
By the rotation of 5, a certain amount of wind is generated by the two PTC heaters 1,
Sent to 2.

When the upper and lower PTC heaters 1 and 2 are selected by operating the selection switch in the operation unit 21, the connection switching unit 22 selects the two PTC heaters 1 and 2. The operation content shown, that is, all relays 1
The operation contents for urging 0 to 12 are sent to the relay drive unit 13.

In response to this operation content, the relay drive unit 13
Energizes all relays 10-12 and closes their relay contacts 10a-12a. When the heating temperature is set in the operation unit 21, the energization control unit 23 compares the set temperature of heating with the actual room temperature, and uses two PTC heaters so that the actual room temperature is maintained at the set temperature. The duty ratio control is performed for 1 and 2.

That is, the energization control unit 23 includes the power supply unit 24.
A zero-cross point is detected from the AC waveform of, and based on this zero-cross point, information is repeatedly transmitted to the relay drive unit 13 by alternately energizing and deenergizing both the relays 10 and 11.

As a result, the relay drive section 13 alternately energizes and deenergizes the relays 10 and 11 alternately for each zero-cross point of the AC waveform. Therefore, since the relays 10 and 11 are alternately energized and deenergized repeatedly while the two PTC heaters 1 and 2 are connected in parallel to the commercial power source 3, the two PTC heaters 1 and 2 are repeatedly activated. For the heaters 1 and 2,
As shown in FIG. 2, the electric powers of the respective half-wave waveforms which are 180 ° out of phase with each other are supplied.

That is, the PTC heaters 1 and 2 are alternately supplied with electric power having a half-wave waveform and are not energized at the same time. By such energization control, each PTC heater 1,
When half-wave power is supplied to 2, the PTC heaters 1 and 2 generate heat, and this heat is output as warm air by the air blow from the blower fan 15.

The control of the supply of the half-wave waveform power by the energization control unit 23 is such that the relays 10 and 11 are energized to activate the PTs until the actual room temperature reaches a temperature near the set temperature for heating.
Full-wave AC power is supplied to the C heaters 1 and 2, and after that, it is detected that the actual room temperature has reached the vicinity of the set temperature of heating,
From this time point, control may be performed so as to supply electric power having a half-wave waveform to the PTC heaters 1 and 2.

By controlling the two PTC heaters 1 and 2 to be supplied with electric power of a half-wave waveform in this way, for example, when the set temperature is 20 ° C. in the automatic operation, the temperature of the warm air can be finely adjusted. As shown in FIG. 3, the room temperature has little fluctuation near the heating set temperature.

Further, by controlling so as to supply the electric power of the half-wave waveform to the two PTC heaters 1 and 2, as compared with the case of supplying the full-wave electric power while keeping the air volume of the warm air constant. As a result, it is possible to save about 15% to 30%.

That is, the characteristics of the PTC heaters 1 and 2 are:
As shown in FIG. 4, the resistance value increases as the temperature increases. Because of this characteristic, if power of a half-wave waveform is supplied to the two PTC heaters 1 and 2, it is possible to save about 15% to 30% of the amount of power while keeping the volume of warm air constant.

By the way, when, for example, only the upper PTC heater 1 is selected by operating the selection switch in the operation unit 21, the connection switching unit 22 causes the upper PTC heater 1 to be selected.
The operation content indicating the selection, that is, the operation content for energizing the relays 10 and 12 is sent to the relay drive unit 13.

In response to this operation content, the relay drive unit 13
Energizes each of the relays 10 and 12, and each relay contact 1
Close 0a and 12a. Further, when the heating temperature is set in the operation unit 21, the energization control unit 23 compares the set temperature of heating with the actual room temperature, and the upper PTC heater 1 so that the actual room temperature is maintained at the set temperature. The duty ratio control is performed for.

That is, the energization control unit 23 detects the zero-cross point from the AC waveform of the power supply unit 24 in the same manner as above,
Based on this zero-cross point, information is repeatedly sent to the relay drive unit 13 that only the relay 10 is energized and deenergized.

As a result, the relay drive unit 13 repeats energizing and deenergizing the relay 10 for each zero-cross point of the AC waveform. Therefore, since the relay 10 is repeatedly energized and deenergized while the upper PTC heater 1 is connected to the commercial power source 3, the upper PTC
The heater 1 is supplied with electric power having a positive half-wave waveform, for example.

When electric power of a half-wave waveform is supplied to the upper PTC heater 1 by such energization control, the upper PTC heater 1 is
The TC heater 1 generates heat, and this heat is output as warm air by blowing air from the blowing fan 15.

In this way, even if the half-wave waveform power is controlled to be supplied only to one of the PTC heaters, for example, the upper PTC heater 1, when the set temperature is 20 ° C. in the automatic operation, the temperature of the warm air is delicate. Can be adjusted to a room temperature, and the room temperature will not fluctuate around the set temperature of heating.

Further, the amount of electric power is about 15% to 30% as compared with the case where full-wave electric power is supplied with the amount of warm air kept constant.
You can save electricity. On the other hand, when the operation unit 21 selects to connect the two PTC heaters 1 and 2 in series by operating the selection switch, the connection switching unit 22 receives this operation and releases the bias of the relay 12. The operation content is sent to the relay drive unit 13.

In response to this operation content, the relay drive unit 13
Releases the energization of the relay 12, and its relay contact 12a
open. As a result, the two PTC heaters 1 and 2 are connected in series to the commercial power supply 3.

In this state, when the heating temperature is set by the operation unit 21, the energization control unit 23 compares the set temperature of heating with the actual room temperature so that the actual room temperature is maintained at the set temperature. Conductivity control is performed on the two PTC heaters 1 and 2.

That is, the energization control unit 23 detects the zero-cross point from the AC waveform of the commercial power source 3 in the same manner as above,
Based on this zero-cross point, the relay drive unit 13 sends information that repeatedly energizes and deenergizes the relays 10 and 11 at the same time.

As a result, the relay drive section 13 repeatedly energizes and deenergizes the relays 10 and 11 simultaneously for each zero-cross point of the AC waveform. Therefore, in the state where the two PTC heaters 1 and 2 are connected in series to the commercial power source 3, the relays 10 and 11 are repeatedly energized and deenergized simultaneously, so that the two PTC heaters are Half-wave power is supplied to 1 and 2.

When the half-wave waveform power is supplied to the two PTC heaters 1 and 2 connected in series by such energization control, these PTC heaters 1 and 2 generate heat, and this heat is blown by the blower fan 15. It is output as warm air by blowing air from.

Even if the two PTC heaters 1 and 2 are connected in series and controlled so as to supply half-wave power as described above, if the set temperature is 20 ° C. in the automatic operation, the temperature of the warm air is delicate. Can be adjusted to a room temperature, and the room temperature will not fluctuate around the set temperature of heating.

Further, the amount of electric power is about 15% to 30% as compared with the case where full-wave electric power is supplied with the amount of warm air kept constant.
You can save electricity. In addition, since the two PTC heaters 1 and 2 are connected in series, the combined resistance value becomes larger than when the PTC heaters 1 and 2 are connected in parallel, and the inrush current at power-on can be reduced.

Further, as shown in FIG. 5, each PTC heater 1,
Since the warm air can be blown from the entire area of the blower path in which the two are arranged, the warm air can be blown uniformly and a cool air feeling is not given. Thus, in the above embodiment, two PTCs are used.
Electric power of each half-wave waveform having a phase difference of 180 ° from each other is supplied to the heaters 1 and 2, and the heat generated in the PTC heaters 1 and 2 at this time is blown as warm air by driving the blowing fan 15. Therefore, the amount of electric power to each of the PTC heaters 1 and 2 can be minutely controlled while keeping the amount of warm air constant, and thereby the temperature of warm air can be finely adjusted, and the room temperature can be set near the set temperature of heating. It can be one with little fluctuation.

For example, in the heating operation, when the hot air blowing temperature is high, if the power of the half-wave waveform is supplied to the two PTC heaters 1 and 2, the hot air blowing temperature can be lowered a little. In addition, the amount of electric power at this time can be controlled to be small.

By supplying electric power of a half-wave waveform to the two PTC heaters 1 and 2, it is possible to operate with a slightly reduced maximum electric power amount, which can be used as a so-called breaker countermeasure.
Further, since the electric power of the half-wave waveform is controlled to be supplied to the two PTC heaters 1 and 2, the electric power amount is about 15% as compared with the case of supplying the full-wave electric power while keeping the hot air amount constant. You can save electricity by 30%.

Therefore, compared to the case where the full-wave power is supplied as the amount of electric power, the amount of electric power can be saved to a small amount even if the amount of warm air is the same. For example, warm air that is not too hot can circulate the air in the room. it can.

Further, since the two PTC heaters 1 and 2 are connected in series to blow hot air, it is possible to reduce the rush current when the power is turned on, and to uniformly blow hot air, giving a cool air feeling. Absent.

The present invention is not limited to the above-mentioned embodiment, but may be modified as follows. For example, control of power supply to the two PTC heaters 1 and 2 is not limited to supply of half-wave waveform power, but the power supply frequency of the commercial power supply 3 is detected, and the two PTC heaters 1 and 2 are respectively controlled. It is also possible to perform the duty ratio control in which a cycle pattern is repeated such that the power is supplied during the four-cycle period and the power is stopped during the next two-cycle period.

Even in the case of such a duty ratio control method, as in the case of the above-described embodiment, each P is kept constant while keeping the hot air volume constant.
The amount of electric power to the TC heaters 1 and 2 can be minutely controlled, the temperature of the warm air can be finely adjusted, and the room temperature can be made to have little fluctuation near the set temperature of heating. Moreover, the amount of electric power can be saved as compared with the case where full-wave power is supplied, while keeping the amount of warm air constant.

In addition to the relays 10 to 12, the switching element may be replaced by a triac, and the duty ratio control for the two PTC heaters 1 and 2 may be performed. Next, a case where the present invention is applied to a heat storage type electric warmer will be described as an application example of the present invention.

FIG. 6 is a block diagram of a heat storage type electric warmer.
A heat storage tank 31 is arranged inside the housing 30. The heat storage tank 31 has a heat storage heater 32 at its center.
Is arranged, and the heat storage material 32 is covered with the heat storage material 33.

A heat insulating material 34 is arranged around the heat storage tank 31 to provide thermal insulation. The heat insulating material 34 has an opening formed below, and an air layer heat insulating portion 35 is formed between the heat insulating material 34 and the heat storage tank 31.

Two PTC heaters 1 and 2 are provided below the opening of the heat insulating material 34. These PTC
A blower port 36 and an intake port 37 are formed on the front surface and the rear surface of the lower portion of the housing 30 in which the heaters 1 and 2 are arranged, respectively.

Of these, a warm air louver 38 is formed at the air blow port 36, and a shutter 39 is provided at the intake port 37 side. The shutter 39 is rotated in the direction of the arrow to adjust the amount of air flow, and the amount of air flowing to the heat storage tank 31 side is adjusted by the rotation angle.

Further, the shutter 39 controls the flow of air only on the two PTC heaters 1 and 2 side, or on the PTC heaters 1 and 2 side.
It has a function of switching to either the heat storage tank 31 or the heat storage tank 31.

A fan motor 14 is provided on the rear surface of the housing 30, and a blower fan 15 is attached to the rotation shaft of the fan motor 14. On the other hand, the control system has the relay drive unit 13, the fan drive unit 16, the operation unit 21, and the connection switching unit 2 according to each command issued from the main control unit 20, similarly to the configuration shown in FIG.
2. The energization control unit 23 is centrally controlled, and the description of the functions of these units is the same as the configuration shown in FIG. The heat storage control system for the heat storage heater 32 is also omitted.

With this configuration, when the heat storage for the heat storage material 33 is completed and the preset time for heating is reached, the shutter 39 is rotated and the fan motor 14 is driven to blow air to the two PTC heaters 1. 2 and the heat storage tank 31.

As a result, the heat of the heat storage tank 31 is sent as warm air. In the operation unit 21, for example, 2
When the book PTC heaters 1 and 2 are selected, the connection switching unit 2
2 sends to the relay drive unit 13 the operation content for energizing all the relays 10 to 12. This relay drive unit 13 energizes all the relays 10 to 12, and relay contacts 10a to
12a is closed.

On the other hand, the energization control unit 23 compares the set temperature of heating with the actual room temperature, and controls the energization rate of the two PTC heaters 1 and 2 so that the actual room temperature is maintained at the set temperature. I do.

That is, the energization control unit 23 has the power supply unit 24.
A zero-cross point is detected from the AC waveform of, and based on this zero-cross point, information is repeatedly transmitted to the relay drive unit 13 by alternately energizing and deenergizing both the relays 10 and 11.

As a result, the relay drive unit 13 alternately energizes and deenergizes the relays 10 and 11 for each zero-cross point of the AC waveform. Therefore, since the relays 10 and 11 are alternately energized and deenergized repeatedly while the two PTC heaters 1 and 2 are connected in parallel to the commercial power source 3, the two PTC heaters 1 and 2 are repeatedly activated. For the heaters 1 and 2,
As shown in FIG. 2, the electric powers of the respective half-wave waveforms which are 180 ° out of phase with each other are supplied.

When power having a half-wave waveform is supplied to each of the PTC heaters 1 and 2 by such energization control, these PTC heaters 1 and 2 are
The heaters 1 and 2 generate heat, and this heat is combined with the warm air due to the heat of the heat storage tank 31 and is output as warm air due to the air blown from the blower fan 15.

In the case of such a heat storage type electric hot air blower, particularly when the heating operation is performed only by the PTC heaters 1 and 2, the PTC heaters 1 and 2 are kept at a constant hot air flow rate.
It is possible to finely control the amount of electric power to the air, to finely adjust the temperature of the hot air, to make the room temperature less fluctuating around the set temperature of heating, and to save electricity while keeping the air volume of the hot air constant.

Further, in the heat storage type electric warmer, two P
The power supply to the TC heaters 1 and 2 is controlled by detecting the power supply frequency of the commercial power supply 3 and, for example, the two PTC heaters 1 and 2 are energized during the four cycle periods of the power supply frequency and then energized during the next two cycle periods. The duty ratio control may be performed in which a cycle pattern for stopping the current is repeated.

[0071]

As described above in detail, according to the present invention, it is possible to provide an electric warmer capable of controlling the amount of electric power to the PTC heater while keeping the amount of warm air constant.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an electric warmer according to the present invention.

FIG. 2 is a diagram showing the electric power of each half-wave waveform supplied to two PTC heaters of the same air blower.

FIG. 3 is a diagram showing a room temperature when the temperature is controlled to a preset temperature for heating by the hot air blower.

FIG. 4 is a diagram showing a characteristic of a resistance value with respect to a temperature of a PTC heater.

FIG. 5 is a diagram showing hot air when two PTC heaters are connected in series.

FIG. 6 is a configuration diagram of a heat storage type electric warmer to which the present invention is applied.

FIG. 7 is a configuration diagram of a conventional electric air blower.

FIG. 8 is a diagram showing room temperature control by a conventional electric warmer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Upper PTC heater, 2 ... Lower PTC heater, 10, 11, 12 ... Relay, 13 ... Relay drive part, 14 ... Fan motor, 15 ... Blower fan, 23 ... Energization control part.

Claims (3)

[Claims] 1. An electric warmer for energizing a ceramic heater and driving a blower fan to blow the heat generated in the ceramic heater as warm air, wherein a duty ratio control is performed for controlling the duty ratio of the ceramic heater. An electric warm air blower characterized by comprising: 2. An electric temperature for energizing a plurality of ceramic heaters and driving a blower fan to blow a constant amount of air to the plurality of ceramic heaters, and to blow the heat generated in these ceramic heaters as warm air. An electric hot air blower, comprising: a duty ratio control means for controlling a duty ratio of at least one ceramic heater among the plurality of ceramic heaters. 3. The electric warmer according to claim 1, wherein the duty ratio control means supplies the electric powers of the respective half-wave waveforms which are 180 ° out of phase with each other to the two ceramic heaters.