JP2009283332A - Ptc sheet heater control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a PTC sheet heater control device which detects the deterioration state of a heater, has a fast rising time, and is safe and comfortable. <P>SOLUTION: The control device is equipped with an abnormality detection section 2, a control section 3, a voltage variation section 4, a power source on/off section 5, a temperature detection section 6, a notification section 7, and a power switching section 8. The control section 3 detects a supply power voltage at a heater current flowing starting time, detects the deterioration state of the heater from a current value and the supply power voltage detected by the abnormality detection section 2, a temperature detected by the temperature detection section 6, and PTC characteristic data and reference initial heater resistance value data, and variably controls a heater voltage according to the deterioration state of the heater, whereby the deterioration state of the heater is detected, and the rising time is made fast not depending on the supplied power voltage within a range of allowed heater current according to the deterioration state of the heater, so that safety and comfortableness are improved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control device for a PTC seat heater that can be used as a heat source for heating or the like.

  Conventionally, this type of PTC heater control device prevents overcurrent at a predetermined value at the start of energization without detecting the deterioration state of the heater.

That is, as shown in FIG. 7, it is comprised from the electricity supply shift means 102 which shifts the electricity supply to the heater 101 in time, and the control part 103 which operates the said electricity supply shift means 102 in the initial stage of electricity supply. reference).
Japanese Patent Application Laid-Open No. 9-65984

  However, in the conventional configuration, since the deterioration state of the heater cannot be detected, safety against the deterioration cannot be ensured.

  Therefore, since the current can be limited only by a predetermined value, the rise time depends on the supply voltage, the rise time cannot be increased, and there is a problem that the rapid thermal performance is poor.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a safe and comfortable PTC seat heater control device that can detect a deterioration state of a heater and that has a fast rise time.

  In order to solve the above-described conventional problems, a PTC seat heater control device according to the present invention includes an abnormality detection unit that detects current and voltage in a path to which a PTC sheet heater is connected, a control unit that controls heater temperature, and a heater. A voltage variable section that varies the voltage, a power on / off section that turns on and off the heater voltage, a temperature detection section that detects the ambient temperature, a notification means that notifies the heater status, and a power source that switches the path of the power supply A switching unit, and the control unit has PTC characteristic data indicating a relationship between temperature and resistance value, reference initial heater resistance value data detected by the abnormality detection unit, and reference allowable heater current value data that can supply power, At the start of heater energization, the supply power supply voltage is detected, and the current value detected by the abnormality detection unit, the detected supply power supply voltage, the temperature detected by the temperature detection unit, and the PTC characteristic data are detected. Data, to detect the deterioration state of the heater from the reference initial heater resistance value data, and variably controls the heater voltage in response to the deterioration of the heater.

  As a result, the deterioration state of the heater can be detected, and within the allowable heater current range according to the deterioration state of the heater, the rise time can be shortened without depending on the supply power supply voltage. Can be improved.

  The PTC seat heater control device of the present invention can detect the deterioration state of the heater and increase the rise time, thereby improving safety and comfort.

  According to a first aspect of the present invention, there is provided an abnormality detection unit for detecting a current and a voltage of a path connected to a PTC seat heater having a resistance temperature characteristic in which a resistance value increases due to a temperature rise, and the resistance value rapidly increases when a certain temperature is reached. A control unit that controls the heater temperature, a voltage variable unit that varies the heater voltage, a power on / off unit that turns the heater voltage on and off, a temperature detection unit that detects the ambient temperature, and a heater status notification And a power supply switching unit that switches a supply power supply path, wherein the control unit is PTC characteristic data indicating a relationship between temperature and resistance value, reference initial heater resistance value data detected by the abnormality detection unit, and power supply It has reference allowable heater current value data that can be detected. At the start of heater energization, the supply power supply voltage is detected, and the current value detected by the abnormality detection unit, the detected supply power supply voltage, the temperature Detecting the deterioration state of the heater by detecting the deterioration state of the heater from the temperature, PTC characteristic data, and reference initial heater resistance value data detected at the outlet, and variably controlling the heater voltage according to the deterioration state of the heater. The rise time can be increased within the allowable heater current range depending on the deterioration state of the heater without depending on the supply power supply voltage, and safety and comfort can be improved.

  In the second invention, in particular, when the control unit of the first invention detects a ground fault of the Reedsen connected to the heater or a short circuit of the heater from the current and voltage detected by the abnormality detection unit, the heater voltage is cut off. The safety including the reed sensor connected to the heater can be improved.

  In the third aspect of the invention, in particular, the control unit of the first or second aspect of the invention notifies the user of the deterioration state of the heater before a complete failure by giving notification according to the deterioration state of the heater at the start of heater energization. Can be informed and repaired.

  The fourth aspect of the invention is used before the season when the heater is necessary, in particular, by notifying the controller according to any one of the first to third aspects of the invention when the heater is not energized, according to the deterioration state of the heater. The person can be informed of the deterioration state of the heater and repaired.

  In the fifth aspect of the invention, in particular, the control unit of any one of the first to fourth aspects of the invention detects the deterioration state of the PTC characteristic when the heater starts up, and variably controls the heater voltage according to the deterioration state of the PTC characteristic. Therefore, safety and comfort including PTC characteristics can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, this invention is not limited by this embodiment.

(Embodiment 1)
1 and 2, an abnormality detection unit 2 that detects current and voltage in a path to which the PTC seat heater 1 is connected, a control unit 3 that controls the heater temperature, a voltage variable unit 4 that varies the heater voltage, and a heater. A power on / off unit 5 for turning on / off the voltage, a temperature detecting unit 6 for detecting the ambient temperature, an informing means 7 for informing the state of a heater such as an LED, and a power source switching unit 8 for switching the path of the power supply It has.

  When the seat heater switch 9 is turned on, the control unit 3 outputs an ON signal to the notification means 7, and the power source switching unit 8 turns on the power source on / off unit 5 with the power supply path set to the seat heater switch side. A power supply voltage is applied to the PTC sheet heater 1.

Thereafter, the control unit 3 detects the supply power supply voltage, calculates the heater resistance value R1 from the heater current value I1 detected by the abnormality detection unit 2 and the detected supply power supply voltage, the heater resistance value R1 and the temperature of the temperature detection unit 7 Calculation of the heater resistance value R1 ′ converted to the reference temperature from the PTC characteristic curve, comparison of the heater resistance value R1 ′ and the initial heater resistance value converted to the reference temperature detected by the abnormality detection unit 3 and stored in the control unit 4, Detection of the heater deterioration state, calculation of the heater current value I1 ′ at the reference temperature from the heater resistance value R1 ′ and the detected power supply voltage, and the allowable heater current at the reference temperature stored in the control unit 4 according to the heater deterioration state The voltage variable section 5 is variably controlled so that the heater temperature rises at the fastest speed at a value IA or less.

  In FIG. 3, the controller 3 detects that the heater short circuit is detected when I1 ′ is equal to or higher than the heater short circuit threshold IB, or the heater voltage V1 detected by the abnormality detector 2 is equal to or lower than the lead wire short circuit threshold VA. When the lead wire short circuit is detected, the heater voltage is cut off.

  In FIG. 4, when detecting deterioration of the heater at the start of energization of the heater, the control unit 3 notifies the user such as blinking of an LED that prompts the user to repair before complete failure.

  In FIG. 5, when the heater is not energized with the seat heater switch 9 turned off, the control unit 3 causes the power source switching unit 8 to change the path of the power source to the power source side that does not pass through the seat heater switch 9, and the arbitrary time interval t1. Then, the deterioration state of the heater is detected, and before the season when the heater is necessary, notification of blinking of the LED or the like that prompts the user to repair is performed.

  In FIG. 6, the control unit 3 calculates the heater resistance value R1 ′ during the heater rising t2, and compares the PTC characteristic curve of the heater resistance value R1 ′ with the PTC characteristic curve stored in the control unit 3. Then, the PTC characteristic deterioration state is detected, and the voltage variable unit is set so that the heater temperature rise is the fastest at the reference heater temperature value IA or less stored in the control unit 3 according to the PTC characteristic deterioration state. 5 is variably controlled.

  As described above, in the present embodiment, the abnormality detection unit that detects the current and voltage of the path to which the PTC seat heater is connected, the control unit that controls the heater temperature, and the voltage variable unit that varies the heater voltage. A power on / off unit for turning on / off the heater voltage, a temperature detecting unit for detecting the ambient temperature, a notifying unit for notifying the heater state, and a power source switching unit for switching the path of the power supply. The unit has PTC characteristic data indicating the relationship between temperature and resistance value, reference initial heater resistance value data detected by the abnormality detection unit, and reference allowable heater current value data that can be supplied with power. Current value detected by the abnormality detection unit, detected supply power supply voltage, temperature detected by the temperature detection unit, PTC characteristic data, reference initial heater resistance value data By detecting the deterioration state of the heater and variably controlling the heater voltage according to the deterioration state of the heater, the deterioration state of the heater can be detected, and within the allowable heater current range according to the deterioration state of the heater, The rise time can be increased without depending on the power supply voltage, and safety and comfort can be improved.

  Note that the determination logic for the heater short-circuit threshold value and the Reedsen ground fault threshold value does not matter.

  Further, in this embodiment, when the control unit detects the ground fault of the Reedsen connected to the heater or the short circuit of the heater from the current and voltage detected by the abnormality detection unit, the control unit is connected to the heater by cutting off the heater voltage. Safety including Reedsen can be improved.

  Further, in this embodiment, the control unit notifies the user of the deterioration state of the heater before the complete failure by performing notification according to the deterioration state of the heater at the start of heater energization, so that the repair can be performed. it can.

  In this embodiment, the control unit notifies the user of the deterioration state of the heater before the season when the heater is necessary by performing notification according to the deterioration state of the heater when the heater is not energized. can do.

  In the present embodiment, the control unit detects the deterioration state of the PTC characteristic when the heater starts up, and variably controls the heater voltage in accordance with the deterioration state of the PTC characteristic, so that the safety and comfort including the PTC characteristic can be achieved. Can be improved.

  As described above, the PTC seat heater control device according to the present invention can detect the deterioration state of the heater and increase the rise time, and can improve safety and comfort. The present invention can also be applied to vehicles such as car seat heaters used and heating appliances.

1 is a block diagram of a PTC sheet heater control device according to Embodiment 1 of the present invention. Flowchart of PTC sheet heater control device in the first embodiment Flowchart of PTC sheet heater control device in the first embodiment Flowchart of PTC sheet heater control device in the first embodiment Flowchart of PTC sheet heater control device in the first embodiment Flowchart of PTC sheet heater control device in the first embodiment Block diagram of a conventional PTC heater control device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 PTC sheet heater 2 Abnormality detection part 3 Control part 4 Voltage variable part 5 Power supply ON / OFF part 6 Temperature detection part 7 Notification means 8 Power supply switching part

Claims (5)

The resistance value rises due to the temperature rise, and when the temperature reaches a certain temperature, the abnormality detection unit that detects the current and voltage of the path to which the PTC sheet heater having the resistance temperature characteristic having the resistance temperature characteristic is connected, and the heater temperature are controlled. A control unit that controls the heater voltage, a power on / off unit that turns the heater voltage on and off, a temperature detection unit that detects the ambient temperature, a notification unit that notifies the heater status, and supply A power source switching unit for switching a power source path, and the control unit includes PTC characteristic data indicating a relationship between temperature and resistance value, reference initial heater resistance value data detected by the abnormality detection unit, and reference allowable heater current capable of supplying power It has value data, and at the start of heater energization, the supply power supply voltage is detected, and the current value detected by the abnormality detection unit, the detected supply power supply voltage, and the temperature detection unit are detected. Temperature, PTC characteristic data, to detect the deterioration state of the heater from the reference initial heater resistance value data, PTC seat heater control device for variably controlling the heater voltage in response to the deterioration of the heater. 2. The PTC sheet heater control device according to claim 1, wherein the control unit shuts off the heater voltage when detecting a short circuit of the lead wire connected to the heater or a short circuit of the heater from the current and voltage detected by the abnormality detection unit. 3. The PTC seat heater control device according to claim 1 or 2, wherein the control unit performs notification according to a deterioration state of the heater when the heater energization is started. The PTC sheet heater control device according to any one of claims 1 to 3, wherein the control unit performs notification according to a deterioration state of the heater when the heater is not energized. The PTC sheet heater control device according to any one of claims 1 to 4, wherein the control unit detects a deterioration state of the PTC characteristic when the heater starts up, and variably controls the heater voltage according to the deterioration state of the PTC characteristic.

Images