JPH0136007B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a gas combustion device, and particularly to a device capable of performing predetermined steady combustion or proportional combustion according to load, almost unaffected by the level of supply gas pressure.

Conventional Structure and Problems Conventionally, this type of gas combustion apparatus has a temperature sensing element 9 installed in the heating water circuit 1 as shown in FIG. Detects the temperature of the heating water whose temperature has increased by exchanging heat with the heat exchanger 2, and turns on the temperature thermometer 10.
The motor 11 is rotated, the fan 13 attached to the tip of the motor shaft 12 provides resistance to the flow of gas in the gas circuit 6, and the amount of gas combusted in the burner 7 is controlled by the heating water. A gas proportional combustion device has been proposed that attempts to maintain a constant heating water temperature by proportionally controlling the temperature. In the configuration of this conventional example, the temperature of the heating water is sensed by the temperature sensing element 9, and the temperature thermostat 10 adjusts the current flowing to the motor 11 and also adjusts the rotation speed of the fan 13 directly connected to the motor 11. This increases or decreases the resistance to the gas flow through the gas circuit, so if the supply gas pressure of the fuel gas sent to homes and combustion equipment is low, the required maximum rated combustion volume cannot be obtained. In order to avoid problems and to avoid excess pressure loss in the gas tank 15, gas circuit 6, etc., it is necessary to maintain a thick gas flow path in the equipment design and configuration, which inevitably requires thick piping. This resulted in problems such as larger diameters and higher costs for the equipment.

Further, although there have been pressurizers for increasing the gas supply pressure for industrial or plant use, they have not been able to automatically vary the discharge pressure or perform proportional combustion.

Purpose of the invention The present invention solves such conventional problems,
It is an object of the present invention to provide a gas combustion device capable of sufficiently and reliably obtaining the maximum rated combustion amount even when the supply gas pressure is low, and further capable of proportional combustion with excellent responsiveness.

Structure of the Invention In order to achieve this object, the present invention includes a sensing element that detects a load or pressure, a controller that outputs an electric signal according to the load or pressure based on a signal from the sensing element, and an electric signal from the controller. A gas pump that changes the suction and discharge amount of fuel gas according to input, and a suction side pipe and a discharge side pipe of the gas pump are connected to each other, and a valve body is attached in a direction to close a valve hole formed on the discharge side pipe. A relief valve device that biases the valve body and changes the biasing force of the valve body according to electrical input from the controller, and a burner that communicates with the discharge side of the gas pump. It has the effect of automatically adjusting the fuel gas pressure supplied to the burner depending on the stage structure.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

Figure 2 shows an application to a gas instantaneous water heater, in which a water pressure responsive gas valve 2 is connected to the gas circuit 20 of the water heater.
1, gas pump 22, tank 23, solenoid valve 24,
A burner 25 and the like are arranged in series with respect to the gas flow, a heat exchanger 27 of the water supply circuit 26 is provided above the burner 25, and a thermistor etc. A temperature sensing element 29 is provided. Furthermore, a pressure sensing element 30 provided in the tank 23, the temperature sensing element 29, a solenoid valve 24, a gas pump driving motor 3,
1 and the like are all electrically connected to the controller 32. The gas pump 22 has a pump casing 3
The rotor 36 rotates while pressing four vanes 34 against the inner wall of the casing 33 with springs 35. gas pump 22
An electromagnetic coil 40 , a ferromagnetic spherical relief valve body 41 , a spring 42 , and a fine adjustment threaded rod 4 are connected to the communication passage 39 that communicates the discharge side passage 37 and the suction side passage 38 .
A relief valve device 44 consisting of 3 and the like is constructed. The controller 32 is also electrically connected to the electromagnetic coil 40.

In the above configuration, when using this gas instant water heater, first set the hot water temperature setting dial (not shown) on the controller 32 to the desired temperature, and then open the hot water faucet (not shown). , the hydraulically responsive gas valve 21 opens, and the motor 31 of the gas pump 22 opens.
And the rotor 36 starts steady rotation. The relief valve device 44 is connected to the tank 23 for a few seconds immediately after the start of operation.
Electrical input is provided from the controller 32 so that the internal pressure of the gas is maintained at a predetermined minimum gas pressure. In other words, the gas pressure signal in the tank is constantly sent to the controller 32 by the pressure detection element 30, and when the gas pressure is lower than the predetermined minimum gas pressure, the electromagnetic coil 40 of the relief valve device 44 is not energized, and when the pressure is higher than the predetermined pressure. In this case, the electric signal input to the electromagnetic coil 40 is increased, and the electromagnetic force of the electromagnetic coil 44 overcomes the force of the spring 42 biasing the valve body 41 in the direction of closing the valve port 45 and closes the valve port. 4
5 is opened, the gas pump discharge side flow path 37 and the suction side flow path 38 are communicated, and an electric signal from the controller 32 is inputted to the relief valve device 44 so as to lower the tank internal pressure. In this way, while maintaining the internal pressure of the tank 23 at a predetermined minimum gas pressure, the solenoid valve 24 is opened in response to a signal from the controller 32, and gas is supplied to the burner 25 to quietly start ignition combustion. 1 to 3 seconds after the start of operation, that is, after the slow ignition as described above, the heat exchanger 27
The controller 32 constantly detects whether the hot water temperature at the outlet side has reached the desired set temperature using a signal from the temperature detection element 29, and the internal pressure of the tank 23 is kept at the predetermined maximum gas pressure until the temperature approaches the set temperature. An electrical signal is input from the controller 32 to the relief valve device 44 so as to maintain the pressure at the same time. In this case, if the tank internal pressure does not reach the predetermined maximum gas pressure, such as when the combustion gas supply pressure to the equipment is lower than the predetermined pressure, the controller 32
In addition to reducing the energization to the electromagnetic coil 40 of the relief valve device 44 to zero, if the predetermined maximum gas pressure is not reached even if the energization voltage to the electromagnetic coil 40 is reduced to zero, the rotation speed of the motor 31 of the gas pump 22 is increased. The controller 32 acts to provide electrical input to the controller 32. Therefore, the maximum rated combustion state is maintained in the burner 25 until the hot water temperature rises to around the desired temperature, so that the desired hot water temperature can be quickly obtained. In the case of a conventional method that adjusts the gas flow path resistance of the gas circuit, when trying to achieve maximum rated combustion,
If the fuel gas supply pressure to the equipment fell below a predetermined gas pressure, the maximum rated combustion could not be ensured. However, in this embodiment, first, the relief valve device 44 is prioritized and controlled while the gas pump 22 is operating at a steady speed, and if the predetermined tank internal pressure cannot be obtained only by controlling the relief valve device 44, the operating speed of the gas pump 22 is also controlled. With this two-stage arrangement, even when the supplied gas pressure is lower than a predetermined pressure, the gas pump 22 sucks it up and discharges it, ensuring maximum rated combustion. In other words, the combustion amount can be controlled almost unaffected by the level of supply gas pressure. Note that the relationship between the operating speed of the gas pump 22 and the gas suction and discharge amount is approximately proportional.

Continuing the operation of this embodiment, when the outlet temperature detected by the temperature detection element 29 rises and approaches the set temperature, the controller 32 operates the gas pump 22 in a steady speed operation state and controls the relief valve Device 4
The input signal to the electromagnetic coil 40 of No. 4 is adjusted according to the difference between the set temperature and the detected temperature, and the current to the electromagnetic coil 40 is gradually increased, acting in the direction of opening the relief valve body 41. The force gradually increases, and the amount of gas released from the discharge side flow path 37 to the suction side flow path 38 also gradually increases. Therefore, the gas pressure in the discharge side flow path 37 and the tank internal pressure acts to gradually decrease, and the amount of gas supplied to the burner 25 also acts to gradually decrease. When the tapped water temperature becomes the same as the set temperature, the amount of current applied to the electromagnetic coil 40 and the operating speed of the gas pump at that time are maintained. When the opening degree of the hot water faucet is further increased to increase the amount of hot water coming out from this state, the calorific load increases and the hot water temperature decreases. Since the water temperature is constantly detected, as soon as it starts to drop, the controller 32 decreases the amount of relief from the relief valve device 44, that is, reduces the amount of current applied to the electromagnetic coil 40, and increases the amount of combustion in the burner 25. Therefore, the hot water temperature is maintained at the set hot water temperature. Conversely, if you close the faucet a little to reduce the amount of hot water coming out, the heat load will also decrease and the water temperature will rise.
The signal change of the hot water temperature detection element 29 is immediately detected by the controller 32.
Since the controller 32 enters the electromagnetic coil 40
The controller 32 first acts to adjust the amount of relief from the relief valve device 44 so that the outlet temperature is always maintained at the set temperature. Electromagnetic coil 4 of relief valve device 44
The controller 32 adjusts or reduces the operating speed of the gas pump 22 only when the amount of current supplied to the gas pump 2 reaches a lower limit of zero or a predetermined upper limit of current, but does not reach a predetermined maximum gas pressure or a predetermined minimum gas pressure, and does not reach the set temperature. act to do so. Therefore, even when the supply gas pressure is low, the maximum rated combustion amount can be reliably ensured, and proportional combustion can be performed according to the load so that the hot water temperature is always maintained at the set temperature.
The relief valve device 44 also includes a small and light spherical valve body 41.
Since it is operated by electromagnetic force, it is possible to respond very quickly, and since the relief valve device 44, which has a quick response, is prioritized and controlled to adjust the amount of gas supplied to the burner 25, it is possible to control hot water temperature hunting, etc. This has the effect of making it possible to create superior equipment without any problems. In the case of the conventional system in which the gas flow path resistance is adjusted using a fan, the response speed is slow due to the influence of the inertia of the fan, and there are problems such as a hunting phenomenon in the water temperature.

Although it is possible to control the hot water temperature by simply adjusting the operating speed of the gas pump 22 in this embodiment in proportion to the load, when comparing the ability to follow sudden load changes, the response speed is By providing a quick relief valve device 44 and controlling the relief valve device 44 with priority over the gas pump 22, proportional combustion that can follow sudden load changes has become possible. Even if the gas supply pressure to the equipment is high or low, the gas pump 2
2 and the relief valve device, a predetermined minimum gas pressure and a predetermined maximum gas pressure can be supplied to the burner 25. The relief valve device 44 is composed of a ferromagnetic mover, a spring 42, and an electromagnetic coil 40, so that, for example, the threaded rod 43 is rotated by a motor to adjust the force of the spring 42 that biases the valve body 41. This has the effect of allowing much more responsive control. By making the valve body 41 spherical and serving both as a movable element and a valve body, the structure is simple and easy to assemble, and the movable part is lighter and has an excellent high-speed response. Furthermore, the gas pressure supplied to the burner 25 differs depending on each gas type, and so-called gas type conversion is generally a troublesome problem in gas appliances. If the minimum gas pressure standard value can be changed electrically by using a switch or by cutting a jumper wire, it will be possible to reduce the time needed to change the gas type.

Effects of the Invention As described above, according to the gas combustion device of the present invention,
The following effects can be obtained.

(1) An element that detects temperature or pressure, a gas pump that forcibly inhales and discharges fuel gas, a high-speed response relief valve device that releases gas from the discharge side of the gas pump to the suction side of the gas pump, and a device that responds to signals from the detection element. The system is composed of a controller that inputs electrical signals to the relief valve device and gas pump, and a burner, so the relief valve device and gas pump respond at high speed according to the load or pressure, and the amount of gas supplied to the burner is controlled. It works to automatically adjust the rate, and maintains a stable maximum rated combustion or steady state with almost no effect even when the gas pressure supplied to the combustion equipment fluctuates or when it is lower or higher than the specified supply gas pressure. Proportional combustion with fast response speed depending on combustion or load is possible.

(2) Since the configuration includes a relief valve device and a gas pump, gas amount control is wide and proportional combustion with excellent responsiveness can be performed to follow rapid load fluctuations.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional gas combustion apparatus, and FIG. 2 is a block diagram showing an embodiment of the gas combustion apparatus of the present invention. 22... Gas pump, 25... Burner, 29...
...Temperature sensing element, 30...Pressure sensing element, 32...
... Controller, 37 ... Discharge side flow path, 39 ... Communication path, 40 ... Electromagnetic coil, 41 ... Valve body, 42 ...
...Spring, 44...Relief valve device.

Claims (1)

[Scope of Claims] 1. A sensing element that detects a load or pressure, a controller that outputs an electrical signal according to the load or pressure based on a signal from the sensing element, and a controller that outputs an electrical signal according to the electrical input from the controller, and a gas pump that varies the suction and discharge amount of the gas pump; and a valve body is biased in a direction to close a valve hole formed on the discharge side conduit side, which connects the suction side conduit and the discharge side conduit of the gas pump, and A gas combustion device comprising: a relief valve device that varies the biasing force of the valve body according to electrical input; and a burner disposed on the discharge side of the gas pump. 2. The relief valve device is comprised of a ferromagnetic mover, a spring, and an electromagnetic coil.
Gas combustion equipment as described in section. 3. The gas combustion device according to claim 1, wherein the relief valve device includes a valve body of a ferromagnetic spherical mover, a spring, and an electromagnetic coil. 4. A temperature sensing element is provided for load detection, and according to a signal from the temperature sensing element, the controller controls the relief valve device with priority, and the gas pump is auxiliarily controlled. gas combustion equipment. 5 A pressure sensing element is provided on the gas pump discharge side, and the controller controls the relief valve device with priority even when the signal of the pressure sensing element is lower than a predetermined minimum gas pressure or higher than a predetermined maximum gas pressure, and the gas pump is 2. The gas combustion device according to claim 1, wherein: is auxiliary controlled. 6. The gas combustion apparatus according to claim 1, wherein the controller has means for electrically switching between the predetermined minimum gas pressure and the predetermined minimum gas pressure reference value.