JP4625254B2 - Automotive temperature controller - Google Patents

Description

  The present invention relates to an on-vehicle temperature control device used for temperature control of an on-vehicle warmed object such as a car seat heater having a blower or a truck nap heater.

  As shown in FIG. 3, this type of on-vehicle temperature control device 1 is configured to pass an in-vehicle warming object 3 such as a car seat heater in which a linear heating element 2 is meandered and air to the in-vehicle warming object 3. The linear heating element 2 and the blowing device are connected to a blowing device 5 such as a fan for blowing air to the skin of the vehicle seat, and the temperature signal from the thermistor 4 disposed in the vicinity of the linear heating element 2 5, the temperature of the linear heating element 2 is adjusted by individually controlling a plurality of current control elements (not shown) such as power MOS FETs connected in series. However, in such a configuration, since the thermistor 4 detects the temperature of one point of the vehicle-mounted warming object 3 and adjusts the temperature of the linear heating element 2, the temperature other than the portion where the thermistor 4 is disposed. Cannot be detected. Therefore, for example, when the linear heating element 2 is energized and heated, if clothing or the like is placed in a portion other than the portion where the thermistor 4 is disposed, only the portion where the clothing is placed is overheated. As a result, the temperature of the linear heating element 2 cannot be adjusted accurately, and there is a risk of fire.

  For such a problem, for example, a linear heating element having both a heat generation function and a temperature detection function is used, and temperature detection is performed over the entire length of the linear heating element. Has proposed a method for highly accurate temperature detection and fire prevention. (For example, refer to Patent Document 1.)

  According to Patent Document 1, accurate temperature adjustment is possible by temperature detection over the entire length of the linear heating element, and it is possible to avoid the risk of overheating and fire due to thermal insulation of a part of the in-vehicle warmed object. It is said that safety can be obtained.

  As a technique related to the present invention, a patent application has been filed by the applicant (see Patent Document 2). This patent document 2 has not been disclosed yet.

  On the other hand, when the skin of the vehicle seat is heated by sunlight or the ambient temperature around the vehicle, heat from the surface of the skin and perspiration from the user of the vehicle seat are caused by ventilation of the vehicle seat by the blower. However, if the temperature of the surface of the epidermis is permanently lowered below the skin temperature due to excessive ventilation, supercooling that impairs comfort will occur.

  For such a problem, for example, when the surface temperature of the skin detected by the temperature sensor is lower than a reference value, a method of switching off the blower has been proposed. (For example, refer to Patent Document 3.)

  According to Patent Document 3, when a temperature sensor is disposed at a specific location of a vehicle seat and the temperature detected by the temperature sensor is lower than a reference value, the risk of overcooling is eliminated by switching off the blower. It is said that.

JP 58-214290 A Japanese Patent Application No. 2002-38429 Japanese Patent No. 3108673

  However, the temperature control apparatus as described above has the following drawbacks. When heating is performed by energizing a linear heating element, when the vehicle-mounted warming object is assembled inside the skin of the vehicle seat and energization is started from a low temperature state, a wire having both a heat generation function and a temperature detection function The temperature of the linear heating element and the temperature signal rise at substantially the same speed, and then the energization of the linear heating element 2 stops when the temperature signal of the linear heating element 2 reaches the set temperature. However, since it takes a long time for the temperature of the linear heating element to conduct heat to the skin surface, the temperature of the skin surface has not yet reached the set temperature at the time when the energization of the linear heating element is stopped. After the energization of the linear heating element is stopped and the temperature of the linear heating element is decreased, the temperature of the skin surface is also decreased until the linear heating element is energized again. However, since the heat capacity of the in-vehicle warmed object and the vehicle seat itself is large, the temperature decrease on the surface of the skin is slower than the temperature decrease of the linear heating element. Therefore, by repeatedly energizing and stopping the linear heating element, the temperature of the skin surface gradually rises, and eventually reaches a temperature close to the set temperature of the linear heating element and becomes stable. However, it will take time to do so. In particular, in the case of car seats, if the temperature on the surface of the skin does not reach the set temperature within a short time, comfort will be greatly impaired, so the vehicle will be equipped with a linear heating element that has both a heat generation function and a temperature detection function. It has become a big problem in the warming.

  On the other hand, when the temperature of the skin surface of the vehicle seat is lowered by air blowing and water vapor due to perspiration is absorbed, if the temperature sensor is limited to a specific position of the vehicle seat, the temperature sensor is provided. Even if it is ventilated to the part that is not done, and the temperature falls locally and becomes supercooled, the temperature sensor does not detect that it is locally supercooled, and the blower device remains in operation, Loss of comfort has been a major problem. Furthermore, when heating by energizing the linear heating element, it is equipped with an in-vehicle temperature control device that controls the temperature of the linear heating element by the temperature signal of the temperature detection line, and the temperature of the skin of the vehicle seat is controlled by blowing air. In the case of lowering the temperature, a vehicle-mounted temperature control device that controls the blower device by the temperature signal of the temperature sensor is necessary separately, and the cost increases.

  The present invention has been made on the basis of such points, and the object of the invention is a vehicle-mounted warming object using a linear heating element and a blower that have both a heat generation function and a temperature detection function. To provide a comfortable and safe in-vehicle temperature control device that can be controlled to reach a set temperature in a short time from a low temperature state, and that does not have a local supercooling state by air blowing at a low cost. It is in.

In order to achieve the above object, an on-vehicle temperature control device according to claim 1 of the present invention is provided with a linear heating element having both a heat generation function and a temperature detection function, and a thermistor for detecting the temperature of the linear heating element. A vehicle-mounted temperature control device that adjusts the temperature of a vehicle-mounted warmed object that is disposed in a state and is disposed in a blower path of a blower device, using a temperature signal of the thermistor and a temperature signal of the linear heating element. A first signal obtained by comparing a voltage of the temperature signal of the thermistor and a first reference voltage; a second signal obtained by comparing a voltage of the temperature signal of the linear heating element and a second reference voltage; A third signal obtained by comparing the voltage of the temperature signal of the linear heating element and a third reference voltage, and a fourth signal obtained by comparing the voltage of the temperature signal of the linear heating element and a fourth reference voltage. When, is outputted, current system for controlling the current of the linear heating element Element, and the signal of the logical sum of said first signal and said second signal, said is adapted to be driven by a logical product signal of the third signal, the current control element for and controlling the blower, It is configured to be driven by the fourth signal .

  According to the present invention, control for reaching a set temperature in a short time from a low temperature state even in a vehicle-mounted warming object that uses a linear heating element and a blower that have both a heat generation function and a temperature detection function. In addition, a comfortable and safe vehicle-mounted temperature control device that does not have a local supercooling state by air blowing can be realized at low cost.

  An embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 3, the in-vehicle temperature control apparatus 1 according to the present embodiment includes an in-vehicle warming object 3 including a linear heating element 2 and a thermistor 4 disposed in proximity to the linear heating element 2. And connected to the blower 5. Here, as shown in FIG. 4, the linear heating element 2 includes a heating wire 2a made of nickel chrome alloy or the like and a temperature detection wire 2c made of nickel or the like through an insulator 2b made of polyamide resin, fluororesin or the like. It has a heat generation function and a temperature detection function. Moreover, the air blower 5 is comprised from the fan which operate | moves with the voltage of the battery for vehicles.

  The circuit configuration of the on-vehicle temperature control device 1 is as shown in FIG. Here, in this embodiment, the comparator U1, the comparator U2, the comparator U3, and the comparator U4 use a quad type with a single power supply. However, the comparator U1, the comparator U2, and the comparator U4 may be operational amplifiers, and in this case, pull-up is performed. The resistor R8, the pull-up resistor R9, and the pull-up resistor R13 can be omitted. The current control element Q1 and the current control element Q2 are power MOS FETs (2SK3483-Z), and the diodes D1 and D2 are small signal types. The thermistor 4 has one end connected to the power supply line Vcc and the other end connected to the inverting input terminal of the comparator U1 and is connected in series with the resistor R5. The voltage Vst of the temperature signal detected by the thermistor 4 is compared with the first reference voltage Vr1 set by the resistance values of the resistors R6 and R7 connected to the non-inverting input terminal of the comparator U1, and the result is compared with the comparator U1. Output V1. On the other hand, one end of the temperature detection line 2c is connected to the ground line GND, and the other end is connected to the resistor R1 together with the comparator U2 inverting input terminal. The voltage Vsk of the temperature signal of the linear heating element 2 is compared with the second reference voltage Vr2 set by the resistance values of the resistors R2, R3, and R4 connected to the non-inverting input terminal of the comparator U2, and as a result Becomes the output V2 of the comparator U2. The output terminal of the comparator U1 is pulled up by a resistor R8. The diode D1 connected to the output terminal of the comparator U1 is connected on the cathode side to the diode D2 connected to the output terminal pulled up by the resistor R9 of the comparator U2. Therefore, an output having a higher voltage of the output V1 of the comparator UI and the output V2 of the comparator U2 is obtained at this connection point. A so-called logical sum output is obtained. Thus, when either the output V1 of the comparator U1 based on the temperature signal Vst based on the temperature detection of the thermistor 4 or the output V2 of the comparator U2 based on the temperature signal Vsk of the linear heating element 2 is high level, The output of the logical sum is also high. Thereby, when heating switch S1 is ON, the current control element Q1 to which the output of the logical sum is connected is energized, and the temperature of the linear heating element 2 rises. As a result, even in the in-vehicle warming object 3 using the linear heating element 2, as shown in FIG. 2 (a), the in-vehicle warming object 3 has a long time to rise from the low temperature to the set temperature. The time-consuming problem will be solved.

  Further, when air is blown so that air passes through a portion other than the portion where the thermistor 4 of the on-vehicle warming material 3 is disposed, and a part of the linear heating element 2 is cooled, the temperature detection signal Vst of the thermistor 4 is Since it remains high, the output V1 of the comparator U1 is at a low level. On the other hand, since the temperature of the linear heating element 2 becomes low, the output V2 of the comparator U2 becomes high level. In this case, since the logical sum signal of the output V1 of the comparator U1 and the output V2 of the comparator U2 is at a high level, the linear heating element 2 is energized. As shown in FIG. There is also an effect that the temperature of the linear heating element 2 is not lowered.

  On the other hand, the temperature detection line 2c is also connected to the inverting input terminal of the comparator U3, and is compared with the third reference voltage Vr3 of the non-inverting input terminal of the comparator U3. The result is the output V3 of the comparator U3. The output terminal of the comparator U3 is further connected to the connection point of the cathodes of the diodes D1 and D2. Here, when the voltage Vsk of the temperature signal of the linear heating element 2 becomes higher than the third reference voltage Vr3, the output of the comparator U3 becomes low level. However, since the output terminal of the comparator U3 has an open collector structure, the logical sum signal at the connection point of the diode D1 and the diode D2 is forcibly set to a low level. In other words, a logical product signal of the logical sum signal at the connection point of the diodes D1 and D2 and the output V3 of the comparator U3 is obtained. Thereby, when the voltage Vsk of the temperature signal of the linear heating element 2 becomes higher than the third reference voltage Vr3 due to partial heat insulation, the output of the comparator U3 becomes low level, and the logical sum of the comparator U1 and the comparator U2 is obtained. Regardless of the signal, the logical product signal is low. As a result, the current of the linear heating element 2 is cut off, and as shown in FIG. 2C, a highly safe temperature control device that can prevent an abnormal temperature rise can be realized.

  On the other hand, the temperature detection line 2c is also connected to the non-inverting input terminal of the comparator U4, and the voltage Vsk of the temperature signal of the temperature detection line 2c depends on the resistance values of the resistors R11 and R12 connected to the inverting input terminal of the comparator U4. The result is compared with the set fourth reference voltage Vr4, and the result is the output V4 of the comparator U4. The output terminal of the comparator U4 is pulled up by a resistor R13. When the vehicle-mounted warmed object 3 disposed near the surface of the skin is heated by sunlight or the ambient temperature around the vehicle, the voltage Vsk of the temperature signal of the linear heating element 2 becomes higher than the fourth reference voltage Vr4. When the output of U4 is at a high level and the ventilation switch S2 is on, the current control element Q2 is energized and the blower 5 is in the operating state. As a result, the air supplied from the blower 5 passes through the in-vehicle warmed object 3 disposed in the blower path of the blower 5, lowers the temperature of the in-vehicle warmed object 3, and is adjacent to the in-vehicle warmed object 3. Absorbs heat on the surface of the epidermis. When the on-vehicle warming material 3 is locally cooled by the air flow and the voltage Vsk of the temperature signal of the linear heating element 2 becomes lower than the fourth reference voltage Vr4, the output of the comparator U4 becomes low level, and the current control element Q2 Is shut off, and the blower 5 is stopped. In this way, it is possible to prevent the temperature of the in-vehicle warmed object 3 and the skin surface from being overcooled.

  As described above, the on-vehicle temperature control device 1 configured to compare the voltage of the temperature signal of the temperature detection line 2c with the reference voltage having a different voltage value for each case of heating and air blowing, Since considerable parts can be used in common, a very inexpensive on-vehicle temperature control device 1 can be realized.

  In addition, the air blower 5 is not limited to a fan, For example, the front air conditioning unit connected with the ventilation path of the vehicle seat by the cold wind path may be sufficient. In this case, there is an effect that the temperature of the in-vehicle warmed object 3 and the surface of the skin is reduced very quickly by using cool air as the air flow. Further, as another example, for example, a tube used as a ventilation path as disclosed in Japanese Patent Application Laid-Open No. 2003-4688 can be considered. However, in this case, when a user sits on the vehicle seat and a compressive force is applied due to the weight of the user, the tube at that portion may be blocked, and the effect of blowing air may be lost. Therefore, for example, as shown in FIG. 5, a plurality of tubes 7 are aligned in parallel, and a tube unit in which adjacent tubes 7 are bonded to each other is connected to the outlet of the fan 8 as a ventilation path 6 to connect the blower 5. Then, even if the user sits on the vehicle seat and the compression force due to the weight of the user is applied, the tube 7 constituting the ventilation path 6 is bonded to the adjacent tube 7, so that the compression force is high. Dispersed in the plurality of tubes 7, none of the tubes 7 is completely crushed and blocked, and the effect of blowing can be sufficiently obtained. Here, considering the comfort of the user of the vehicle seat, the tube 7 is made of a material that does not become too hard even at a low temperature and can maintain a required strength even at a high temperature. An elastomer or the like is suitable.

  The in-vehicle temperature control device of the present invention can reach a set temperature in a short time from a low temperature state even for an in-vehicle warmed object using a linear heating element and a blower device that have both a heat generation function and a temperature detection function. Such a control is possible, and there is no local supercooling due to air blowing, and it is comfortable and safe. Applications include, for example, temperature adjustment of in-vehicle warming objects such as a car seat heater having a blower and a nap heater for trucks.

It is a circuit diagram which shows one Example of the vehicle-mounted temperature control apparatus by this invention. It is a figure explaining operation | movement of the vehicle-mounted temperature control apparatus by this invention, (a) is the period which raises the temperature of a vehicle warming material to setting temperature, (b) is one of the vehicle warming materials other than the arrangement | positioning part of a thermistor. When the part is cooled, (c) shows the surface temperature of the in-vehicle warmed object when a part of the in-vehicle warmed object other than the portion where the thermistor is arranged is thermally insulated. It is a figure for demonstrating the structure of in-vehicle warming material. It is a figure for demonstrating the structure of the linear heat generating body which has a heat_generation | fever function and a temperature detection function. It is a figure for demonstrating one Example of an air blower.

Explanation of symbols

U1, U2, U3, U4 comparators R1-R14 Resistors D1, D2 Diodes Q1, Q2 Current control element S1, Heating switch S2, Blower switch Vcc Power supply line GND Grounding line 1 In-vehicle temperature control device 2 Linear heating element 3 In-vehicle use Heated material 4 Thermistor 5 Blower 6 Ventilation path 7 Tube 8 Fan

Claims (1)

An in-vehicle warming object in which a linear heating element having both a heat generation function and a temperature detection function and a thermistor for detecting the temperature of the linear heating element are arranged in the proximity of each other and arranged in a blowing path of the blower Is a vehicle-mounted temperature control device that adjusts the temperature of the temperature by the temperature signal of the thermistor and the temperature signal of the linear heating element,
A first signal obtained by comparing the voltage of the temperature signal of the thermistor with a first reference voltage; a second signal obtained by comparing the voltage of the temperature signal of the linear heating element and a second reference voltage; A third signal obtained by comparing the voltage of the temperature signal of the linear heating element and a third reference voltage; and a fourth signal obtained by comparing the voltage of the temperature signal of the linear heating element and a fourth reference voltage. , Is output,
The current control element for controlling the current of the linear heating element is configured to be driven by a logical product signal of the logical sum of the first signal and the second signal and the third signal ,
The on-vehicle temperature control device is characterized in that the current control element for controlling the blower is driven by the fourth signal .

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