JPH0631312Y2 - Forced intake / exhaust combustion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Use and Outline of the Invention] The present invention relates to a forced intake / exhaust combustion device, and more particularly to a control device thereof, and in detecting the presence of air flow in the intake / exhaust passage, An attempt is made to detect an air flow in an intake / exhaust passage by generating an air flow associated with the air flow on an electric element mounting board of a control device and changing an electric value of the electric element caused by the generation of the air flow. Is. As a result, the detection device for detecting the presence / absence of the intake / exhaust flow can be of a non-contact type, and further, the remote wiring for the detection unit unlike the conventional method (method using a wind pressure switch) is unnecessary.

[Prior Art and its Problems] In the combustor of forced intake / exhaust type, a differential pressure type wind pressure switch (10) is provided in the intake / exhaust passage as shown in FIG. The method of controlling the combustion of the burner (20) by detecting the air flow generated in the air is adopted (Japanese Patent Publication No. 58-2335).

In this case, when there is no air flow in the intake and exhaust passages, the differential pressure type wind pressure switch (10) is turned off to stop the combustion. Therefore, the combustion can be stopped when the blower does not operate or when there is an abnormality such as clogging of the intake and exhaust passages, and safety is secured in this respect.

However, in this conventional one, since the differential pressure type wind pressure switch (10) is made to correspond to the intake and exhaust passages, the electric element group in the electric combustion control device (1) and this wind pressure switch (1)
0) needs to be electrically connected and the wind pressure switch (1
(0) must be sufficiently heat resistant.

[Technical problem] The present invention detects the presence or absence of an air flow in the forced intake / exhaust passage and electrically controls the combustion of the burner.
In the above, in order to simplify the wiring to the detection device for detecting the presence or absence of the air flow, and to prevent this detection device from being required to have a high degree of heat resistance, the detection device is combined with the electric elements of other control devices. The technical problem is to be able to position it on the mounting substrate (11).

[Technical Means] The technical means of the present invention for solving the above technical problem is "a mounting substrate (11) in which combustion control type electric elements are arranged.
In addition, an air flow detection element (12) whose electrical characteristics change depending on whether atmospheric air is flowing or stopped is provided, and the vicinity of this air flow detection element (12), the intake and exhaust passages, and the communication pipe (3) are connected. Connected via the air flow detecting element (12), and a signal output from the air flow detecting element (12) is used as a combustion control device (1). ), The combustion control device (1) has an air flow detection element (12).
Is configured to burn the burner (20) only when the air flow is detected ”(see FIG. 1).

[Operation] The above technical means operates as follows.

When there is an air flow in the intake / exhaust passage, a pressure difference is generated between both ends of the communication pipe (3), and an air flow is generated in the communication pipe (3). Be exposed to the airflow.

As a result, the electrical characteristics of the airflow detecting element (12) change, a signal corresponding to this is input to the combustion control device (1), and the burner (20) burns.

On the contrary, when there is no air flow in the intake / exhaust passage, the above-mentioned signal output does not occur, and the combustion control device (1) stops the combustion of the burner (20).

As described above, according to the above technical means, the combustion is controlled according to the presence / absence of the flow of air in the intake / exhaust passage, that is, whether or not the intake / exhaust is smoothly performed.

[Effect] The present invention has the following unique effects.

Since the air flow detecting element (12) is arranged on the mounting substrate (11) together with the electric elements of the combustion control device (1), the electric wiring between these elements is simple.

Further, since the airflow detecting element (12) is placed under the same temperature condition as other electric elements apart from the intake / exhaust passage, heat resistance is not required.

Furthermore, since each electric element is concentrated on the mounting substrate (11), repair and inspection are easy.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

In the embodiment shown in FIG. 2, one end of the communication pipe (3) is provided in the exhaust passage (4) and the other end is provided on the mounting substrate (11) as a thermistor (12) as an air flow detecting element (12). It is a configuration that has reached the vicinity of 13).

The end of the communication pipe (3) on the exhaust passage (4) side is bent to the downstream side as shown in the figure, and the bent end (31) is attached to the bent end (31).
The venturi (41) is fixed to the exhaust passage (4) by fitting the venturi (41) onto the outside. Mounting board (11) for communication pipe (3)
The end portion on the side is opened to a box body (14) accommodating the thermistor (13), and in this box body (14), an air inflow hole (on the wall surface facing the open end (32) of the communication pipe (3) ( 15) and (15) are opened.

A positive temperature coefficient thermistor is used as the thermistor (13), and a type in which the resistance rapidly increases above a certain temperature is used. As shown in FIG. 3, the thermistor (13) is connected in parallel with a reference voltage setting circuit (51) for comparison, and the high potential side output of the thermistor (13) and the reference voltage setting circuit.
The output of (51) is input to the comparator (52), and the output of this comparator (52) activates the circuit of the combustion control device (1). For this reason, a switching transistor (53) is inserted in the power supply circuit to the combustion control device (1), and a comparator is provided at the base of this switching transistor (53).
The configuration in which the output from (52) is input is adopted.

In this embodiment, when an air flow occurs around the thermistor (13), the temperature of the thermistor (13) is lowered, which causes the output from the comparator (52) to be in a high level state. Only at this time combustion control device (1)
The power supply circuit to is turned on. That is, the combustion control device
(1) becomes the operating state.

Exhaust path is when airflow is generated around the thermistor (13).
Since it corresponds to the case where a predetermined exhaust flow occurs in (4),
The same safety as the conventional one can be ensured by the device of this embodiment.

In addition, in the above embodiment, a bent end is provided at one end of the communication pipe (3).
Since the (31) is formed and provided in the exhaust passage (4), when the exhaust flow is generated in the exhaust passage (4), the suction pressure reliably acts on the communication pipe (3). Further, the venturi (41) further enhances the above effect.

Next, a second embodiment shown in FIG. 5 is intended to cool the thermistor (13) from the intake passage (5) side with cold air based on positive pressure, and in this case also, the same as in the first embodiment. To function.

Furthermore, in the third embodiment shown in FIG. 6, hot air based on the positive pressure from the exhaust passage (4) is made to act on the thermistor (13) as the air flow detecting element (12). As the thermistor (13), one having a characteristic opposite to that of the first embodiment is adopted.

In this case as well, the same function as in the first embodiment can be obtained, but it is also possible to detect whether or not the burner (20) is burning.

As the air flow detection element (12), a negative characteristic thermistor, a positive characteristic thermistor as a positive characteristic thermistor, or a transistor can be adopted. It can be used as a flow detection element (12).

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a principle diagram of the present invention, FIG. 2 is an explanatory diagram showing a first embodiment of the present invention, and FIG. 3 is an electrical circuit explanatory diagram of essential parts thereof.
FIG. 4 is an explanatory view of a conventional example, FIG. 5 is an explanatory view of the second embodiment, and FIG. 6 is an explanatory view of the third embodiment. In the figure, (1) ... Combustion control device (3) ... Communication pipe (4)… Exhaust passage (11)… Mounting board (12)… Air flow detection element (13)… Thermistor (20)… Burner (31)… Bend end

Claims (1)

[Scope of utility model registration request] 1. A method for electrically controlling combustion of a burner by detecting the presence or absence of an air flow generated in a forced intake / exhaust passage, wherein atmospheric air is provided on a mounting substrate (11) on which combustion control type electric elements are arranged. An air flow detection element (12) whose electrical characteristics change depending on whether it is flowing or stopped is provided, and the vicinity of this air flow detection element (12) and the intake / exhaust passage are connected via a communication pipe (3). When the air flow is generated in the intake and exhaust passages, a pressure difference is created between both ends of the communication pipe, and the signal output from the air flow detection element (12) is input to the combustion control device (1). ,
The combustion control device (1) is a forced intake / exhaust combustion device configured to burn the burner (20) only when the air flow detection element (12) detects an air flow.