JP2006185766A - Temperature controller for ptc heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature controller for PTC heater which can control to a prescribed heater temperature easily, without using a temperature sensor for directly detecting the temperature, and from the start of switching-on to even after reaching a prescribed temperature. <P>SOLUTION: The temperature controller 1 for PTC heater is provided with a current sensor 13 for detecting current value flowing to a PTC heater 3, and performs control to change the ratio of switching-on and switching-off time according to the current value detected. The prescribed control is carried out by deviation from the current value specified according to the desired heater temperature established beforehand. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a temperature controller for a PTC heater that controls the temperature of a PTC heater that is a planar heating element.

  Recently, floor heating has been performed using a planar heating element having a PTC characteristic (property of increasing resistance with increasing temperature).

  In general, air conditioning in a room is intensively performed by an air conditioner or the like. For this reason, the entire room is not at a uniform room temperature, and there is a considerable temperature difference depending on the location. In particular, in winter, warm air due to temperature control does not reach the floor surface, and in summer, cold air stagnates on the floor surface, impairing comfort. Therefore, indoor temperature control can be effectively performed by arranging a floor heating device having the planar heating element at a specific location.

  In recent years, OA equipment such as personal computers has been increasing, and the room temperature may be set to an appropriate temperature for expensive OA equipment by setting the temperature to be optimal for people. In particular, a personal computer or the like often sets the room temperature relatively low because the amount of heat generation increases as the usage time increases.

For this reason, there is a case where it is desired to partially heat a specific floor in the room, such as when there is a request to partially heat the vicinity of the floor where people are present, and only the floor at a specific location is to be changed to a floor-heated floor. There is. In addition, as an example, a double floor for wiring provided with a surface heating element is disclosed. (For example, see Patent Document 1)
Further, there has already been published an application in which the temperature of the PTC heater is adjusted by adjusting the current value flowing to the heater side after the heater reaches the stable region. (For example, see Patent Document 2)
JP-A-6-341655 (page 1-3, FIG. 1) JP 2004-259557 A (page 1-8, FIG. 1)

  When it is desired to partially heat the floor, a heater such as a stove may be installed. However, an extra object is placed on the floor, which may interfere with the appearance.

  Since the heater unit having the PTC characteristic has its own temperature control, it is not necessary to additionally provide a temperature control mechanism. For this reason, when temperature control is performed, a temperature control mechanism that uses an element with a large number of parts such as a new temperature sensor and a thermistor is added to ensure temperature control and safety.

  As described above, when a temperature sensor is provided to detect the temperature of the heater, it is necessary to install the sensor in the vicinity of the heater and the heater, and to wire the sensor cable. Necessary.

  Further, simply controlling the value of the current supplied to the heater unit requires a great deal of time to raise the temperature to a predetermined heater temperature at the start-up at the start of energization. Therefore, it is necessary to control the current value to be energized after confirming that the temperature of the heater unit has reached the predetermined temperature without controlling the current value until the heater temperature becomes predetermined. .

  In order to solve the above problems, the object of the present invention is not to use a temperature sensor that directly detects the heater temperature, and can be easily controlled to a predetermined heater temperature even after reaching a predetermined temperature from the start of energization. A temperature controller for a PTC heater is provided.

  In order to achieve the above object, the invention according to claim 1 is a controller for controlling the temperature of a PTC heater having a PTC characteristic in which a resistance value increases as the temperature increases, and a value of a current supplied to the PTC heater. And a control for changing the ratio of the on / off time of energization to a preset ratio in accordance with the detected current value.

  According to the first aspect of the present invention having the above-described configuration, the heater temperature is controlled by the value of the current supplied to the heater from the start of energization to the heater until it stabilizes at a predetermined temperature and continuously after the stabilization. Can be controlled.

  The invention according to claim 2 specifies a heater temperature corresponding to the detected current value, and at a predetermined ratio according to a deviation between the specified heater temperature and a predetermined heater temperature set in advance. It is characterized in that the on / off time of energization is controlled.

  According to the second aspect of the invention having the above configuration, the heater temperature can be efficiently controlled even after reaching a predetermined heater temperature from the start of energization.

  The invention according to claim 3 is characterized in that one cycle period of energization on / off time is a time set constant for each PTC heater in accordance with the characteristics of the PTC heater.

  According to the invention which concerns on Claim 3 which has said structure, the temperature of a heater can be controlled with the period suitable for each heater.

  The invention according to claim 4 is a controller for controlling the temperature of a PTC heater having a PTC characteristic in which a resistance value increases with an increase in temperature, a current sensor for detecting a current value energized in the PTC heater, A power conversion unit that converts a current value that has been converted into a DC voltage value to calculate a power value that is actually supplied, and compares the calculated power value with a power value that corresponds to a heater temperature that is defined in advance. And a controller that changes the ratio of on / off time of energization to a preset ratio according to the detected deviation.

  According to the invention which concerns on Claim 4 which has said structure, the temperature of a heater can be easily set and controlled to arbitrary temperatures.

  The invention according to claim 5 is the heater unit case in which the PTC heater is composed of a heat insulating material, a planar heating element, and a metal protective casing that covers the insulating sheet in an integrated manner. It is a planar heating element applied to a floor heating free access floor that is configured by laying the heater unit case body and a tile carpet in order on a support base provided with a body and projecting legs downward. It is characterized by.

  According to the invention which concerns on Claim 5 which has said structure, the heater temperature of the free access floor with a floor heating provided with a PTC heater can be set to arbitrary temperature, and can be controlled.

  As described above, according to the present invention, predetermined control is performed by performing control according to the value of current supplied to the heater from the start of energization to the heater until the temperature is stabilized at a predetermined temperature and continuously after the stabilization. The heater temperature can be quickly reached, and a predetermined heater temperature can be maintained. Furthermore, since the control is performed with a cycle period suitable for each heater characteristic, the heater temperature can be controlled efficiently.

  Embodiments of a PCT heater temperature controller according to the present invention will be described below with reference to FIGS. 1 to 4.

  As shown in FIG. 1, a PTC heater 3 which is a planar heating element having PTC characteristics according to the present invention has conductive electrode foils arranged in a comb shape from the left and right, and the right electrode foil 3a and the left side in the figure. It is a thin film-like sheet that has an electrode foil 3b and in which a heating material 3c made of semiconductor ink is sealed. In addition, both surfaces are insulated by a film.

  Further, the terminal portion 3 </ b> A protruding outward from the PTC heater 3 is accommodated in a notch portion 2 </ b> A provided in the heat insulating material 2. Therefore, even when the terminal cover 3Aa is attached to the terminal portion 3A, the terminal cover 3Aa can be completely accommodated in the cutout portion 2A without protruding to the upper surface side of the PTC heater 3. Furthermore, a lead wire 3B extending from the terminal portion 3A is wired to the control panel 10 via the controller 1.

  In a normal thin electric heater heating element that does not have PTC characteristics, a feedback control device is required to adjust the heat generation temperature, which is expensive. However, the PTC heater 3 is a self-temperature control type heating element having a so-called positive heat characteristic (referred to as a PTC characteristic) in which the electrical resistance increases as the temperature rises. It becomes possible to adjust. Therefore, it is preferable to employ the PTC heater 3 according to the present invention as a planar heating element for floor heating.

  Next, referring to FIG. 3, the PTC heater 3, the heat insulating material 2, and the insulating sheet 4 are accommodated and integrated in a metal protective casing 5 formed in a box shape by bending four sides of a metal plate. A free access floor F with floor heating will be described.

  The floor heating free access floor F shown in the figure is a heater unit case body CA integrated with a PTC heater on a resin support base 6 for constituting a wiring space as a double floor structure. And a tile carpet 7 or the like is further laid thereon to form a floor.

  In the heater unit case body CA, a heat insulating material 2, a PTC heater 3, and an insulating sheet 4 are stacked in order from bottom to top in a metal protective casing 5 formed in a box shape by bending four sides of a metal plate. Unitized as a unit.

  At this time, two pieces of the box-shaped metal protective casings 5 and 5A face each other to form a case body, and the heat insulating material 2, the PTC heater 3 and the insulating sheet 4 are formed in the case body CAa. Is configured to surround (cover) the electric circuit with a conductor (in this case, metal protective casings 5 and 5A), and electromagnetic waves emitted from the electric circuit are diffused to the outside. This can be further reduced, which is preferable.

  The heat insulating material 2 is a plastic foam material for building materials having a thickness of about 5 to 20 mm, and is a commercially available material generally used for floor heating. This heat insulating material 2 has the effect of efficiently heating the floor without releasing the heat of the PTC heater 3 under the floor.

  The insulating sheet 4 is an electrically insulating sheet made of synthetic rubber or plastic and having a thickness of about 1 mm (or less). In order to ensure electrical safety, the PTC heater 3 and a metal protective casing are used. It was set as the structure used by pinching between 5.

  The metal protective casing 5 is a box-shaped casing having a flat upper surface that is bent in four directions downward, and even if a person walks on the floor heating free access floor in which the heating member 1 is incorporated, The PTC heater 3 is a member that protects the PTC heater 3 from being damaged when a seated caster chair rides on or sits down, and is a casing made of an aluminum alloy plate or an iron plate.

  The metal protective casing 5 is a heat equalizing plate that uniformly transfers the heat generated by the PTC heater 3 to the floor surface, and is a protective plate for improving the strength of the floor surface. It may be a plate material. However, if the box-shaped case body structure in which the heat insulating material 2, the PTC heater 3, and the insulating sheet 4 are integrally stored in the box shape as described above, the structural strength is improved. The heater unit case body CA can be handled as an integral unit.

  The effective area of the PTC heater 3 is a portion where the heat generating material 3c is disposed and is smaller than the total area of the floor with floor heating, but due to the heat transfer effect of the metal protective casing 5, the heater unit case The entire floor surface of the body CA can be set to a uniform temperature. That is, the metal protective casing 5 is a protective plate and a soaking plate. Therefore, an aluminum alloy with good heat conductivity is particularly suitable as the material for the metal protective casing 5.

  A plurality of U-groove cutout portions 6b for wiring are provided on each of the four sides of the resin support base 6 on which the heater unit case body CA is placed. In addition, the notch 6b serves as a wiring path to OA equipment and electrical devices installed on the floor, and can easily be placed in the lower space below the floor formed by the legs 6a of the resin support base 6. It can be wired.

  Therefore, since the wiring does not appear on the floor, there is no need to worry about the wiring, and the floor heating free access floor F including the heater unit case body CA can be arranged at any position in the room. Any place can be individually heated.

  When the PTC heater 3 is energized at a predetermined voltage at the start of heating, the heating material 3c between the comb-like right electrode foil 3a and the left electrode foil 3b generates heat. At this time, a current corresponding to the resistance of the heat generating material 3c (which varies depending on the temperature) is applied. Since the heat generating material 3c has a so-called positive heat characteristic (referred to as PTC characteristic) in which the electrical resistance increases as the temperature rises, the current that is energized decreases as the temperature rises, reducing the power consumption, It has a self-temperature control type feature that does not raise the temperature above a predetermined temperature. Therefore, the temperature does not rise above a predetermined design temperature, and it is safe and has good electric efficiency.

  Furthermore, in the present invention, the PTC heater temperature controller 1 is provided in order to quickly reach a desired heater temperature and perform more efficient heater temperature control. Therefore, it is possible to arbitrarily set the floor heating temperature on a cold day or a relatively warm day, and a more comfortable indoor environment can be obtained.

  The temperature controller 1 for a PTC heater according to the present invention is a device for controlling the power supplied to the PTC heater 3, and the length of energization on / off according to the value of the current energized to the PTC heater 3. The amount of heat generated is controlled by changing the supplied power. FIG. 2 shows an outline of the temperature controller 1 for a PTC heater. FIG. 2A is a block diagram showing a main configuration thereof, and FIG. 2B is a graph showing a relationship among a current value, a resistance value, and a heater temperature. (C) is a graph which shows the ratio and the pattern of ON / OFF control.

  As shown in FIG. 2A, the PTC heater temperature controller 1 has a current sensor 13 for detecting a current value energized (supplied) to the PTC heater 3 and the detected current value is preset. A power converter 14 that calculates an actual power value by converting an alternating current into a DC voltage for comparison with a power value, and a deviation for detecting a deviation between a preset power value and the actual power value And a detector 11. In addition, a setting unit 15 for setting a target power value in advance is provided in the control panel 10 and is detected by comparing a power value preset by the setting unit 15 with the calculated actual power value. The controller unit 12 is configured to control energization on / off based on the deviation.

  The control method will be described with reference to the graphs shown in FIGS. Since the PTC heater 3 has a property (PTC characteristic) in which the resistance value increases as the temperature increases, the PTC heater 3 generates heat in advance by the supplied power (proportional to the current value that is energized when the voltage is constant). The amount is specified. Therefore, the heater temperature at that time can be specified corresponding to the current value detected by the current sensor 13. Further, when a desired heater temperature is set in advance, a predetermined current value (power value) is specified corresponding to the set temperature, so that the set current value (power value) and the actual current value detected (power value) The amount of generated heat can be adjusted by detecting a deviation from the power value) and performing control according to the deviation.

  Therefore, in this embodiment, the energization on / off time is set at a predetermined ratio according to the deviation between the current value that can be specified for the desired heater temperature (T ° C.) and the current value that is actually detected. It was set as the structure controlled. In other words, the heater temperature Ta ° C. is specified for a high current value A in the figure where the heat generation temperature is still low at the start of energization, and at that time, one cycle (P) of the energization control cycle is specified. Of these, 80% was defined as the on (energization) time, and 20% was defined as the off (non-energization) time.

  Further, when the current value B in a state where the temperature slightly increased was detected, the heater temperature at this time was specified as Tb ° C., and 50% of the control cycle P was set as the energization time. When the current value C in a state where the temperature further increased was detected, the heater temperature at this time was specified as Tc ° C., 20% of one period P of the control cycle was set as the energization time, and 80% was set as the non-energization time.

  As described above, by setting the time ratio of the on / off time of energization to a predetermined ratio according to the current value that is actually supplied, in a low temperature state and when the supplied current value is large, Like the control WA shown in the figure, the heater temperature can be quickly raised by supplying power for a longer time. Further, when the heater temperature gradually rises and the supplied current value decreases, the energization time is controlled to be shortened according to the current value, so that the energization time shown in the figure is 50%. The control pattern is sequentially changed from WB to the control WC where the energization time is 20%, and the temperature increase can be gradually suppressed. For this reason, the temperature can be quickly increased to the target heater temperature, but the temperature cannot be increased to a predetermined temperature or higher.

  In addition, one period of the energization control cycle P is a time that is set constant according to the characteristics of each PTC heater, and is an appropriate time according to the characteristics of the PTC heater depending on the material of the heating material to be used. Can be set to

  As described above, the temperature controller 1 for a PTC heater according to the present invention specifies the heater temperature from the current value that is actually energized, and further feeds it back according to a deviation from a preset desired heater temperature. Thus, the heater temperature can be controlled by performing a predetermined pattern control in which a preset ratio of on / off time is changed.

  Therefore, it is not necessary to provide a separate temperature sensor for detecting the heater temperature, and no new wiring is required.

  When floor heating is performed using the floor heating free access floor F provided with the heater unit case body CA, the size of the heater unit case body CA may be the same as that of the single resin support base 6, In the present embodiment, the resin support base 6A has a size of about 25 cm on a side. Therefore, as shown in the figure, the resin support base 6A has a width and a length that combine the two resin support bases 6A and 6B. The size of a square with a side length of about 50 cm, which is simultaneously laid on a total of four small resin supports.

  That is, in this embodiment, a floor heating device (heater unit case body) can be laid for each 50 cm square free access floor.

  Further, the size of the resin support base 6 is set to be the same as that of the conventional resin support base, and the height thereof is set to the same height as that of the conventional resin support base with the heater unit case body CA mounted. Thus, the tile carpet 7 can be shared and laid. Therefore, it is possible to lay the tile carpet 7 over the conventional free access floor and the floor access free access floor, and even if a part of the floor is renovated to the floor access free access floor, There is no difference in level, and there is no sense of incongruity.

  Further, as described above, a plurality of U-groove notches 6b are provided on each of the four sides of the resin support base 6, so that wiring to OA equipment and electrical devices installed on the floor is performed under the floor. The wiring cable or the like does not appear on the floor.

  FIG. 4 shows an example of an office where a floor heating free access floor is disposed on a conventional free access floor, but only a portion where a person is located is a floor heating free access floor having a PTC heater 3. It is a top view which shows a place. The floor controllers 21A, 21B, 21C, and 21D on which people in the office 20 are located are free access floors with floor heating, and the PTC heater temperature controller that maintains a predetermined heater temperature by controlling each PTC heater 3 on and off. 1 and a control panel 10 are provided.

  The control panel 10 can individually set the heat generation amounts of the plurality of PTC heaters 3. By using the PTC heater temperature controller 1 that controls the energization timing and the on / off time ratio in a preset pattern according to the current value actually supplied for each PTC heater 3, respectively. The heat generation temperature of the PTC heater 3 is set to a predetermined temperature, is efficiently maintained at the predetermined temperature, and power consumption can be kept low.

  Although the PTC heater 3 has self-temperature control performance, the indoor living environment can be changed and set for each season and every day by controlling the timing of energization and the on / off ratio. it can. Therefore, a temperature sensor, a thermostat, etc. are unnecessary, and there is no extra electrical equipment, so that the installation work to be installed is simplified. In addition, the running cost can be reduced because control is performed not to energize constantly but to provide a time for turning off at a predetermined rate and not energizing.

  The free access floor with floor heating provided with the temperature controller for PTC heaters according to the present invention has a configuration in which the heating members are unitized, and can be easily replaced with the conventional free access floor portion. Therefore, the layout of the floor heating free access floor can be easily changed in response to the change in the arrangement and size of desks and OA equipment in the office.

  Further, since the heat generation temperature of the PTC heater 3 can be controlled for each heater unit, the temperature environment at each position in the room can be adjusted.

It is a top view which shows an example of the PTC heater which concerns on this invention. The outline | summary of the temperature controller for PTC heaters concerning this invention is shown, (a) is a block diagram which shows the main structures, (b) is a graph which shows the relationship between an electric current value, resistance value, and heater temperature, (C) is a graph showing the ratio and pattern of on / off control. Sectional drawing of the heater unit case body provided with a PTC heater is shown. It is a top view which shows an example of the office by which the floor access free access floor provided with a heater unit case body is arrange | positioned.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Temperature controller for PTC heater 2 Heat insulation material 3 PTC heater (planar heating element)
DESCRIPTION OF SYMBOLS 4 Insulation sheet 5 Metal protective casing 10 Control panel 11 Deviation detection part 12 Controller part 13 Current sensor 14 Power conversion part

Claims (5)

A controller for controlling the temperature of a PTC heater having a PTC characteristic in which a resistance value increases with an increase in temperature,
A current sensor for detecting a current value to be supplied to the PTC heater is provided, and control is performed to change the ratio of on / off time of the current supply to a preset ratio according to the detected current value. A temperature controller for PTC heaters.   The heater temperature corresponding to the detected current value is specified, and the energization on / off time is controlled at a predetermined ratio according to the deviation between the specified heater temperature and a predetermined heater temperature set in advance. The temperature controller for a PTC heater according to claim 1, wherein the temperature controller is used.   The temperature for a PTC heater according to claim 1 or 2, wherein one cycle period of the on / off time of energization is a time set constant for each PTC heater according to the characteristics of the PTC heater. controller. A controller for controlling the temperature of a PTC heater having a PTC characteristic in which a resistance value increases with an increase in temperature,
A current sensor that detects a current value that is supplied to the PTC heater; a power conversion unit that calculates a power value that is actually supplied by converting the supplied current value into a DC voltage value; and a calculated power value. A deviation detection unit that detects a deviation by comparing a power value corresponding to a heater temperature defined in advance, and a controller unit that changes a ratio of energization on / off time to a preset ratio based on the detected deviation And a temperature controller for a PTC heater. The PTC heater includes a heater unit case body composed of a heat-insulating material, a sheet heating element, and an insulating sheet, and a metal protective casing that integrally covers them, and facing downward. The heating element is a planar heating element applied to a floor heating free access floor configured by sequentially laying the heater unit case body and a tile carpet on a support base having a protruding leg. 5. The temperature controller for a PTC heater according to any one of 4 above.

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