JP2011220607A - Fan forced heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly circulate indoor air without giving a user discomfort due to cold air by surely cooling a combustion chamber in interrupting a heating operation.SOLUTION: A mixing air pathway 20 and a combustion air pathway 5 communicated with a first intake port 14 and the combustion chamber 4 are defined in a body case 11 having a first intake port 13, the second intake port 14 and a supply port 12. The mixing air pathway is communicated with the first intake port and the supply port and provided with the combustion chamber 4 having a gas burner 41 and a convective fan 3 inside thereof. The combustion air is supplied into the combustion chamber from the second intake port through the combustion air pathway by a combustion fan 6. The convective fan mixes the mixing air sucked from the first intake port with the combustion air discharged from the combustion chamber and supplies the same from the supply port. A control part 8 executes a post purge operation for extinguishing the gas burner and driving the combustion fan and the convective fan for a prescribed time when a room temperature reaches an operation interruption temperature and the convective fan is stopped, and the combustion fan is continuously operated until the room temperature reaches an operation restart temperature after the post purge operation.

Description

  The present invention heats indoor air in a combustion chamber having a gas burner, mixes the heated air with room temperature air so as to reach a predetermined temperature, and blows warm air from the warm air outlet into the room. It relates to a heater.

  Conventionally, in a gas hot air heater, a duct communicating with an air inlet and an air outlet, a combustion chamber having a gas burner provided in the duct, and a blower fan are provided in a main body case provided with an air inlet and an air outlet. There is one provided (Patent Document 1). In this gas hot air heater, room air is sucked into the duct by sucking room air from the intake port by rotating the blower fan, and a portion of the sucked air is introduced into the combustion chamber and heated. The interior is heated by blowing the warm air into the room from the air outlet.

  In a gas hot air heater having a temperature control function, the set temperature set by the user and the actual room temperature detected by the indoor temperature sensor provided near the air intake in the main body case are approximately. The combustion amount of the gas burner and the blowing amount of the blower fan are adjusted so as to match.

JP-A-11-23064

  In the temperature control of the gas warm air heater described in Patent Document 1, when the room temperature becomes higher than the set temperature, the gas burner is extinguished and the heating operation is interrupted. At this time, the blower fan is rotated at a slow speed to circulate room air. When the room temperature falls to the heating resumption temperature near the set temperature, the gas burner is burned and the air blowing fan is rotated at the maximum speed to resume the heating operation, whereby the room temperature is maintained at the set temperature.

By the way, the gas hot-air heater having a temperature control function needs to circulate room air in order to accurately detect the room temperature. Therefore, even after the gas burner is extinguished, the blower fan is continuously rotated. However, when the blower fan is operated at the maximum rotational speed, cold air is gradually blown from the outlet, giving the user an unpleasant cold wind feeling. become.
On the other hand, in order to suppress the feeling of cool air, it is conceivable to reduce the rotational speed of the blower fan after extinguishing the gas burner, but in that case, the circulation of the indoor air becomes insufficient, and the problem that the indoor temperature cannot be accurately detected. is there. In addition, in the case of a hot air heater having an indoor temperature sensor for detecting the indoor temperature in the main body case, the temperature inside the main body case is high after the gas burner is extinguished. As a result, there is a problem that the gas burner is not re-ignited even though the room temperature is equal to or lower than the heating resumption temperature.

  The present invention has been made in view of the above circumstances, and even when the heating operation is interrupted, a high-temperature portion in the main body case, such as a combustion chamber, can be reliably cooled, and the user is uncomfortable with the cold air. It aims at providing the warm air heater which can perform the circulation of indoor air favorably.

The hot air heater according to the present invention is
A body case having a first air inlet, a second air inlet, and a hot air outlet;
A mixed air passage which is provided in the main body case, communicates with the first air inlet and the air outlet, and in which a combustion chamber having a gas burner is disposed;
A combustion air passage communicating with the second intake port and the combustion chamber;
A combustion fan for supplying combustion air into the combustion chamber from a second intake port via the combustion air passage;
Provided in the mixed air passage, sucks the mixing air from the first intake port, sucks the combustion air from the combustion chamber, and discharges the mixed air of the combustion air and the mixing air to the outlet With convection fans that blow out from
An indoor temperature detector provided near the second air inlet in the combustion air passage;
Based on the room temperature detected by the indoor temperature detector during heating operation control, the gas burner is burned, extinguished, and burned in order to control the temperature of the hot air blown from the outlet so that the room temperature becomes the set temperature. A control unit for controlling the driving of the fan and the convection fan,
The controller performs a post-purge operation to extinguish the gas burner and drive the combustion fan and the convection fan for a predetermined time when the room temperature reaches an operation interruption temperature higher than the set temperature, and stops the convection fan after the post-purge operation. Then, the combustion fan and the convection fan are driven and controlled so that the combustion fan is operated intermittently or continuously until the room temperature reaches an operation restart temperature lower than the operation interruption temperature.

  According to the warm air heater, the temperature control operation is interrupted during the heating operation control, and the combustion fan is driven even when the convection fan is rotated at a slow speed by the start of the post purge operation. Thus, the indoor air can be circulated satisfactorily while reliably cooling the combustion chamber. Furthermore, even when the post-purge operation is completed and the convection fan is stopped, the combustion fan is driven so that the indoor air can flow into the room from the outlet and the first inlet after passing through the combustion room. Accurate room temperature can be detected by sufficiently diffusing the air taken into the body into the room. Moreover, when air is circulated only with the convection fan, air flows out only from the outlet, but when air is circulated only with the combustion fan, air flows into the room separately from the outlet and the first inlet, The amount of air flowing out from the air outlet is reduced compared to the air circulation by the convection fan, and it becomes difficult for the user to feel cold air. In particular, when the gas burner has a combustion plate with good heat storage, the temperature of the combustion plate is higher than room temperature even after the end of the post-purge operation, so the air introduced into the combustion chamber by driving the combustion fan Since it is warmed when passing through the plate and warm air from room temperature can be made to flow from the outlet, it becomes more difficult to feel cold air.

  In the hot air heater of the present invention, the combustion fan is preferably a sirocco fan that is smaller than the convection fan. According to the warm air heater, it is possible to perform reliable intake while reducing the motor noise. Since the motor and the rotating blade of the combustion fan can be made small, the sound caused by these rotations can be reduced. In addition, since a sirocco fan is used, the amount of air sucked can be secured even when static pressure is applied, and combustion air can be smoothly introduced into the combustion chamber.

  Furthermore, the control unit may drive the convection fan at a low rotational speed during the post-purge operation. According to the warm air heater, even in the post-purge operation, the combustion chamber can be sufficiently cooled by driving the combustion fan while the flow rate of the air blown from the outlet can be suppressed.

  As described above, according to the hot air heater of the present invention, the temperature control operation is interrupted during the heating operation control, and even if the convection fan is rotated at a very low speed by the start of the post purge operation, Air can be reliably introduced into the combustion chamber, and the indoor air can be circulated satisfactorily while cooling the combustion chamber reliably. Further, since the combustion fan is driven even after the post-purge operation is finished and the convection fan is stopped, the indoor air is separated from the outlet and the first intake port after passing through the combustion chamber and flows into the room. Since the air can be sufficiently diffused and the flow rate from the air outlet can be reduced as compared with the case where the air is emitted only from the air outlet, the user can hardly feel the cold air. As a result, even if the temperature control operation is interrupted during the heating operation control, the combustion chamber can be cooled and the indoor air can be circulated by driving the combustion fan, so that it is difficult for the user to feel cold air. While circulating the indoor air, it is possible to detect an accurate room temperature and perform good temperature control.

1 is an overall configuration diagram of a gas fan heater that is a hot air heater according to an embodiment of the present invention. It is a control block diagram of the gas fan heater which concerns on this embodiment. It is an operation | movement flowchart of the gas fan heater which concerns on this embodiment.

  Below, the gas fan heater which is the warm air heater which makes one Embodiment is demonstrated, referring drawings.

  With reference to FIG. 1, the gas fan heater 1 of the present embodiment includes a rectangular main body case 11. The main body case 11 has an air outlet 12 formed in a lower portion on the front side, and a first air inlet 13 and a second air inlet 14 having a smaller area than the first air inlet 13 on the back side. . The first air inlet 13 and the second air inlet 14 are covered with a single air filter 15. The air filter 15 is detachably attached to the main body case 11 in order to prevent dust or dust from flowing into the main body case 11.

  In the main body case 11, a duct 2 in which the gas burner 41 and the convection fan 3 are disposed is disposed. Inside the duct 2, a combustion chamber 4 having a gas burner 41 in the upper part is disposed, and a convection fan 3 is provided below the combustion chamber 4.

  The duct 2 communicates with the first air inlet 13 and the air outlet 12 and constitutes a mixed air passage 20 serving as a hot air blowing path, and one inlet side opening 21 that is upstream of the duct 2. Is opposed to the first air inlet 13 formed in the main body case 11, and the other outlet side opening 22 on the downstream side of the duct 2 is opposed to the air outlet 12 of the main body case 11. A movable louver 16 that adjusts the degree of opening is attached to the air outlet 12, and the movable louver 16 is driven by a geared motor 17. The geared motor 17 is driven and controlled by the control unit 8.

  On the side of the duct 2, a combustion air passage 5 communicating with the second intake port 14 is defined. A mixing pipe portion 42 of a gas burner 41 exposed from the side wall of the duct 2 is disposed in the combustion air passage 5. A combustion fan 6 is attached to the base end portion of the mixing tube portion 42. The combustion fan 6 forcibly supplies the air taken into the combustion air passage 5 from the second intake port 14 into the combustion chamber 4 through the mixing pipe portion 42 as combustion air.

  The combustion fan 6 includes a combustion fan motor 61 whose rotational speed changes in proportion to the amount of energized current, a rotating blade 62 that has a large number of small forward blades in a cylinder and is driven to rotate by the combustion fan motor 61. It is comprised by the sirocco fan which has. The combustion fan 6 is provided with a second rotation speed sensor 63 configured by a Hall element or the like for detecting the rotation speed. The second rotation speed sensor 63 is a signal corresponding to the rotation speed of the combustion fan motor 61. Is output to the control unit 8.

  Further, in the combustion air passage 5, a first electromagnetic valve 71, a second electromagnetic valve 72 and a proportional control valve 73 interposed in the gas supply pipe 7 and a control unit 8 are also arranged. The first solenoid valve 71 and the second solenoid valve 72 are opened by energization. In the opened state, the fuel gas is passed in the direction of the nozzle 74 provided at the tip of the gas supply pipe 7 and the energization is stopped. In the valve state, the passage of fuel gas is blocked. The proportional control valve 73 is a valve whose opening increases in proportion to the amount of energization current, and adjusts the amount of fuel gas supplied to the gas burner 41. The first electromagnetic valve 71, the second electromagnetic valve 72, and the proportional control valve 73 are controlled to open by the control unit 8.

  Further, an indoor temperature sensor 91 for detecting the indoor temperature is provided in the combustion air passage 5 in the vicinity of the second intake port 14 in the main body case 11.

  A downstream end of a gas supply pipe 7 for supplying fuel gas to the gas burner 41 is inserted into the mixing pipe portion 42 of the gas burner 41. A nozzle 74 is formed at the distal end of the gas supply pipe 7. The fuel gas ejected from the nozzle 74 and the combustion air introduced from the combustion fan 6 are mixed and introduced into the combustion chamber 4. The

  The gas burner 41 includes a mixing tube portion 42, an all-primary combustion type combustion plate 43 in which a large number of flame holes are formed, and a mixed gas chamber 44 into which a mixed gas of fuel gas and combustion air is introduced from the mixing tube portion 42. Have. The combustion chamber 4 includes a gas burner 41 and a combustion cylinder 45 disposed so as to surround the combustion plate 43. A flow dividing plate 46 is disposed so as to face the upper opening of the combustion cylinder 45.

  An ignition electrode 47 for igniting a mixed gas of combustion air and fuel gas and a thermocouple 48 for detecting the presence or absence of a combustion flame are disposed above the combustion plate 43 in the combustion cylinder 45. Yes. When the thermocouple 48 is exposed to the combustion flame of the gas burner 41, it generates a thermoelectromotive force according to the temperature of the combustion flame, and the thermoelectromotive force is output to the control unit 8.

  From the second intake port 14, the indoor air is sucked into the combustion air passage 5 of the main body case 11 by the operation of the combustion fan 6, introduced into the mixing pipe portion 42, and introduced into the mixing pipe portion 42. The combustion air flows into the mixed gas chamber 44 of the gas burner 41 together with the fuel gas. The combustion exhaust generated by the combustion of the gas burner 41 flows from the opening formed in the upper portion of the combustion cylinder 45 along the flow dividing plate 46 and is discharged into the mixed air passage 20 formed in the duct 2.

  Then, when the room air is sucked into the duct 2 as the mixing air into the duct 2 by the operation of the convection fan 3, the mixing air and the combustion exhaust generated by the combustion of the gas burner 41 are mixed, and the duct The mixed air becomes warm air from the air outlet 12 facing the second air outlet 22 and is blown into the room.

  The convection fan 3 has a convection fan motor 31 whose rotational speed changes in proportion to the amount of energization current, and a rotating blade that is disposed in the mixed air passage 20 facing the outlet 12 and is driven to rotate by the convection fan motor 31. 32. The convection fan 3 is provided with a first rotation speed sensor 33 configured by a Hall element or the like for detecting the rotation speed. The first rotation speed sensor 33 controls a signal corresponding to the rotation speed of the convection fan motor 31. Output to unit 8.

  Although abbreviated in FIG. 1, an operation unit 18 having an operation switch 92, a temperature setting switch 93, and the like is provided on the upper surface of the main body case 11. The operation switch 92 is turned on / off by the user, and instructs the control unit 8 to start and stop the heating operation control. A temperature setting switch 93, which is a room temperature setting device, sets a desired temperature at room temperature, and the desired temperature is increased or decreased by 1 ° C., for example, by a user operation. The set desired temperature is immediately transmitted to the control unit 8.

  Further, the control unit 8 performs rotation control of the convection fan 3 and combustion fan 6 and combustion control of the gas burner 41 based on signals input from detectors such as the thermocouple 48 and the indoor temperature sensor 91.

  Next, the configuration of the control unit 8 will be described with reference to FIG. The control unit 8 is configured using a microcomputer or the like, and includes a temperature setting unit 81, a combustion control unit 82, and a blower control unit 83.

  The temperature setting unit 81 includes a set temperature determining unit 81a, an operation interruption temperature determining unit 81b, and an operation resuming temperature determining unit 81c. The set temperature determining unit 81a determines the temperature set by the temperature setting switch 93 as the set temperature for the heating operation. The operation interruption temperature determination unit 81b determines the temperature obtained by adding 1 ° C. to the set temperature as the operation interruption temperature, and the operation resumption temperature determination unit 81c determines the set temperature as the operation resumption temperature. The operation interruption temperature determined by the operation interruption temperature determination unit 81b and the operation resumption temperature determined by the operation resumption temperature determination unit 81c are output to the combustion control unit 82 and the air blow control unit 83.

  The combustion control unit 82 determines the target combustion amount of the gas burner 41 so that the set temperature and the detected temperature of the indoor temperature sensor 91 substantially match, and is provided in the gas supply pipe 7 so that the gas burner 41 burns at the target combustion amount. By controlling the energization of the first electromagnetic valve 71, the second electromagnetic valve 72, the proportional control valve 73, and the ignition electrode 47, the ignition / extinguishing of the gas burner 41 and the adjustment of the combustion amount (the adjustment of the fuel gas supply amount) Etc.

  Further, the combustion control unit 82 stops the combustion operation of the gas burner 41 by setting the target combustion amount of the gas burner 41 to 0 when the detected temperature of the indoor temperature sensor 91 rises to the operation interruption temperature, and after stopping, the indoor temperature sensor Temperature control is also performed to restart the combustion operation of the gas burner 41 when the detected temperature 91 falls below the operation restart temperature.

  The air blow control unit 83 sets the target rotational speed (the amount of combustion air supplied to the gas burner 41 and the mixing air introduced from the first intake port) according to the combustion amount of the gas burner 41 set by the combustion control unit 82. The amount of current supplied to the convection fan motor 31 and the combustion fan motor 61 is adjusted so that the convection fan motor 31 and the combustion fan motor 61 rotate according to the supply amount). That is, each fan motor 31 is set so that the target rotational speed matches the actual rotational speeds of the convection fan motor 31 and the combustion fan motor 61 detected by the first rotational speed sensor 33 and the second rotational speed sensor 63. , 61 is adjusted.

  Next, with reference to the flowchart of FIG. 3, the control operation of the hot air heater by the control unit 8 will be described.

  When the user turns on the operation switch 92, the heating operation control of the hot air heater by the control unit 8 is started, and the gas burner is ignited (step S11). At this time, the combustion control unit 82 opens the first electromagnetic valve 71 and the second electromagnetic valve 72, energizes the ignition electrode 47 with the opening degree of the proportional control valve 73 being maximized, and ignites the gas burner 41, The control unit 83 drives the convection fan 3 and the combustion fan 6 by maximizing the rotational speeds of the convection fan motor 31 and the combustion fan motor 61.

  When the gas burner 41 is ignited, a temperature adjustment operation based on the set temperature set by the temperature setting switch 93 is started (step S12).

  After the temperature adjustment operation is started, it is determined whether or not the room temperature has exceeded the operation interruption temperature obtained by adding 1 ° C. to the set temperature (step S13). If the room temperature exceeds the operation interruption temperature (Yes in step S13), the temperature adjustment operation is stopped (step S14). And the combustion control part 82 closes the 1st solenoid valve 71, the 2nd solenoid valve 72, and the proportional control valve 73, and the ventilation control part 83 makes the rotational speed of the convection fan motor 31 the minimum, and it is a combustion fan motor The convection fan 3 and the combustion fan 6 are continuously driven with the rotational speed of 61 as the maximum (step S15), and the post purge operation is performed.

  When the post-purge operation is started, it is determined whether or not the post-purge operation has passed a predetermined time (for example, 1 minute) (step S16). The post-purge operation time at this time may be set to a time at which the warm air blown from the air outlet 12 is slightly higher than room temperature so that the user does not feel uncomfortable. If the post-purge operation has passed a predetermined time (for example, 1 minute) (Yes in step S16), the post-purge operation is terminated, and the blowing operation using only the combustion fan 6 is performed (step S17). In this air blowing operation, the convection fan 3 is stopped while the first solenoid valve 71, the second solenoid valve 72, and the proportional control valve 73 are closed, and the combustion fan motor 61 is driven while the rotation speed is maximized. to continue.

  Then, it is determined whether or not the room temperature has become equal to or lower than the set temperature that is the operation restart temperature (step S18). When the room temperature falls to the operation restart temperature (Yes in Step S18), the process returns to Step S11 to ignite and burn the gas burner.

  With the control shown in FIG. 3, the temperature adjustment operation is interrupted during the heating operation control, and the user does not feel the cold wind until the temperature adjustment operation is resumed even after the post purge operation is performed for a predetermined time. In addition, a blowing operation for driving only the combustion fan 6 is performed. By this air blowing operation, the air sucked into the main body case 11 from the second air inlet 14 passes through the combustion chamber 4, but the air is passed through the combustion chamber 4 because the combustion plate 43 is still hotter than the room. Is heated by the combustion plate 43 and blown out from the air outlet 12 and the first air inlet 13 so that the indoor air can be circulated. As a result, the user can circulate indoor air well without feeling a cold wind, and the room temperature sensor 91 provided near the second air inlet 14 can detect the accurate room temperature.

  In this embodiment, the post purge operation time is 1 minute, but the conditions for performing the post purge operation are not particularly limited to this time. For example, a duct internal temperature sensor that detects the temperature in the duct 2 is provided on the flow dividing plate 46 disposed in the duct 2, and the time of the post-purge operation is controlled based on the detected temperature detected by the internal duct temperature sensor. You may do it.

  Further, during the post-purge operation and the air blowing operation, it is possible to measure the accurate indoor temperature by increasing the flow rate of the air flowing through the combustion chamber 4 and the duct 2. Although the fan motor 61 is rotated at the maximum number of rotations, the number of rotations can be set freely. Further, the combustion fan 6 is controlled to continuously rotate the combustion fan motor 61 during the post-purge operation and the air blowing operation. However, the combustion fan 6 may be intermittently operated. In addition, the more accurate indoor air temperature can be measured by continuous operation.

  Further, a combustion air introduction pipe having one end connected to the second intake port 14 and the other end connected to the mixing pipe portion 42 is connected to the side wall of the duct 2, and the combustion air introduction pipe is used for the combustion air. The passage 5 may be configured. In this case, a combustion fan is provided so as to communicate with the combustion air introduction pipe, and an indoor temperature sensor 91 is provided in the vicinity of the second intake port 14 in the combustion air introduction pipe. The combustion air introduction pipe is defined as the duct 2 and incorporated in the main body case 11, and the combustion air passage 5 can have a smaller passage area than the mixed air passage 20. 2. The flow velocity of the combustion air sucked from the intake port 14 can be increased. As a result, an accurate indoor temperature can be measured by the indoor temperature sensor 91 even if the combustion fan 6 is small.

  The present invention is not limited to the above-described embodiments, and various aspects are possible. For example, the convection fan may be provided in the duct 2 near the first intake port 1 between the first intake port 1 and the combustion chamber 4.

DESCRIPTION OF SYMBOLS 1 Gas fan heater 11 Main body case 12 Outlet 13 1st inlet 14 Second inlet 2 Duct 20 Mixed air passage 3 Convection fan 4 Combustion chamber 41 Gas burner 47 Ignition electrode 48 Thermocouple 5 Combustion air passage 6 Combustion fan 8 Controller 91 Indoor temperature sensor (Indoor temperature detector)

Claims (3)

A body case having a first air inlet, a second air inlet, and a hot air outlet;
A mixed air passage which is provided in the main body case, communicates with the first air inlet and the air outlet, and in which a combustion chamber having a gas burner is disposed;
A combustion air passage communicating with the second intake port and the combustion chamber;
A combustion fan for supplying combustion air into the combustion chamber from a second intake port via the combustion air passage;
Provided in the mixed air passage, sucks the mixing air from the first intake port, sucks the combustion air from the combustion chamber, and discharges the mixed air of the combustion air and the mixing air to the outlet With convection fans that blow out from
An indoor temperature detector provided near the second air inlet in the combustion air passage;
Based on the room temperature detected by the indoor temperature detector during heating operation control, the gas burner is burned, extinguished, and burned in order to control the temperature of the hot air blown from the outlet so that the room temperature becomes the set temperature. A control unit for controlling the driving of the fan and the convection fan,
The controller performs a post-purge operation to extinguish the gas burner and drive the combustion fan and the convection fan for a predetermined time when the room temperature reaches an operation interruption temperature higher than the set temperature, and stops the convection fan after the post-purge operation. A hot air heater that drives and controls the combustion fan and the convection fan so that the combustion fan is operated intermittently or continuously until the room temperature reaches an operation restart temperature lower than the operation interruption temperature. The warm air heater according to claim 1,
The combustion fan is a hot air heater that is a smaller sirocco fan than the convection fan. The hot air heater according to claim 1 or 2,
The said control part is a warm air heater which drives a convection fan at low rotation speed at the time of a post purge operation.