JPS5934121B2 - oxygen generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oxygen generator equipped with a plurality of chemical oxygen generators as oxygen sources, and more particularly, to
Do not burn the above multiple oxygen generators at once, but one by one (
The present invention relates to an oxygen generator equipped with a sequential ignition mechanism for automatically and sequentially combusting oxygen (or two or more predetermined numbers) so that oxygen generation is not interrupted.

Chemical oxygen generators such as chlorate candles, which have an alkali metal salt of chloric acid as the main ingredient, and add exothermic agents (e.g., reduced iron powder), chlorine absorbers (e.g., barium peroxide), etc., and form them into wax shapes. has long been known as a safe and easily portable oxygen source, and various oxygen generating devices using it have been proposed.

However, while chemical oxygen generators have many advantages, they also have some disadvantages.

One of these is that the rate of thermal decomposition (and therefore the rate of oxygen generation) is not very easy to control, and the larger the size, the more difficult it becomes to maintain a stable rate of oxygen generation.

Therefore, if the oxygen generation rate does not need to be so high, but stable oxygen generation for a long period of time is required, multiple oxygen generators are prepared, and one or more predetermined number of oxygen generators are used. A method is adopted in which the fuel is sequentially combusted.

In this case, when the oxygen generation from the oxygen generating body during combustion ends or approaches its end, the next oxygen generating body must be immediately ignited to prevent oxygen generation from being interrupted.

Various types of sequential ignition systems can be considered for this purpose, but considering that this type of oxygen generator is often used in emergencies, it is recommended that the structure and operation be as simple and reliable as possible. It is desirable that the

An object of the present invention is to provide an oxygen generator equipped with a sequential ignition mechanism for a plurality of chemical oxygen generators that can meet the above requirements.

The means employed in the present invention to achieve the above object are as follows.

First, for each oxygen generator (excluding the oxygen generator that is ignited last), prepare a thermal switch in the form of a heat sensor consisting of the following items 1 to 2.

■ A metal heat transfer piece with a surface molded to match the shape of the can wall so that it fits tightly against the oxygen generator can wall.

(2) A foam block having rubber elasticity, which is fixed on one side to the back side of the molded surface of the heat transfer piece and on the other side to the substrate.

■ A thermal switch that is buried in the foam block near the heat transfer piece and closes at a high temperature above a specified temperature.

However, the above-mentioned heat sensor may be one in which two sets of heat transfer pieces and a thermal switch are attached to one substrate and a foam block, as in a specific example described later.

Attach the above-mentioned heat sensitive device to the oxygen generating body storage area of the oxygen generating device so that the heat transfer piece and the oxygen generating body wall are in contact with each other. Select one that operates by sensing the rise in can wall temperature due to combustion).

On the other hand, a pressure switch that closes when the oxygen gas flow rate falls below the minimum allowable value is installed at the oxygen gas outlet common to each oxygen generator, and each of the thermal switches is connected in series with the pressure switch.

Wiring is then done so that the ignition voltage for the oxygen generator is supplied via the pressure switch and the thermal switch. By connecting the igniter of the oxygen generating body to be ignited next to the body, when the oxygen generation from the oxygen generating body during combustion ends, the ignition voltage of the oxygen generating body to be ignited next will be automatically adjusted. This was done so that it would be supplied to the public.

The present invention will be described in detail below using a specific example of an oxygen generator equipped with three chlorate candles.

Figure 1 is a partially see-through perspective view of a heat sensitive device with two built-in thermal switches, and Figure 2 is a sectional view taken along line A□A' in Figure 1 (however, the internal structure of the thermal switch is omitted). be).

In both figures, 1 and 1' are heat transfer pieces made of cylindrical chlorate candle cans, which are curved with the same curvature as the cylindrical chlorate candle can wall so that they fit tightly against the can wall. It is glued to body block 2.

Inside the foam block 2 are thermal switches 3, 3'.
It is buried so as to be in contact with the heat transfer pieces 1 and 1'.

4 is a substrate to which the foam block 2 is adhered, 5 is a mounting screw hole thereof, and 6 is a lead wire of a thermal switch.

The thermal switches 3 and 3' are of a bimetallic type similar to those used in thermostats, and are enclosed in a flat copper can, with an electrically insulating coating applied to the surface of the copper can.

FIG. 3 is a partially cutaway perspective view showing the heat sensor installed in the chlorate candle storage area of the oxygen generator.

In the figure, 7 is a heat sensitive device, and 81 B't8'' is a chlorate candle.

The heat-sensor is mounted in such a position that the heat-transfer piece 1 is lightly pressed against the can wall of the chlorate candle 8, and the heat-transfer piece 1' is lightly pressed against the can wall of the chlorate candle 8' by the elasticity of the foam block 2. has been done.

Therefore, when a certain chlorate candle starts to generate oxygen and the temperature of the can wall increases due to the heat of reaction, that heat is transferred to the thermal switch through the heat transfer strip in contact with the chlorate candle, and the temperature of the switch increases to the operating temperature (this When the temperature reaches approximately 70° C. in the example, the switch closes.

FIG. 4 is a schematic diagram showing the mounting location of the pressure switch and an attached mechanism for causing the pressure switch to perform a predetermined operation.

To explain the operating principle of the pressure switch 9, the diaphragm 11 and the rod 12 connected thereto move in response to the pressure in the pressure chamber 10 communicating with the oxygen flow path.
The NC contacts of the switch are opened and closed (the situation shown is when there is no gas flow).

The operating constants and the dimensions of the orifice 13 provided in the oxygen flow path are selected so that the following switch operation is performed.

(1) When the flow rate of oxygen gas is above the minimum allowable value, the pressure switch opens due to the back pressure created by the presence of the orifice.

(11) When the candle burns out and the oxygen gas flow rate becomes lower than the minimum permissible value, the pressure switch closes due to the associated drop in back pressure.

Note that the minimum allowable value of the oxygen gas flow rate is a value that should be appropriately determined depending on the purpose of use of the generated oxygen and the presence or absence or size of an oxygen storage tank.

In this example, the standard flow rate is 25±051/min (25℃...
(converted to 1 atm), the minimum allowable value was approximately 0.31/min.

By providing the orifice 13 in the gas line, when oxygen generation becomes significantly more active than under normal conditions, the pressure within the system may rise too much and become dangerous.

The bypass valve 14 is provided to prevent such an excessive pressure rise, and opens when the pressure rises above a value sufficient to keep the pressure switch open to bypass the gas.

Fig. 5 is an electrical wiring diagram showing a sequential ignition mechanism composed of a conventional thermal switch and a pressure switch, and in the figure, Man and SW are manual switches for starting, and P
-8W is a pressure switch, T-8W is a thermal switch,
H is the nichrome wire of the igniter, and the numbers attached to 1, T-8W, and H indicate the number of the candle to which the switch or nichrome wire is attached.

Before starting the device, pressure switches P, SW are closed and all other switches are open.

Turn the first candle (AI) on the manual switch Man-8
When W is closed and ignited, oxygen begins to be generated.

As soon as the flow rate exceeds the minimum allowable value, the pressure switch P-
Since 8W opens, even if the thermal switch T-8W closes later due to a temperature rise in the can of candle &1, no current will flow through the nichrome wire H2.

When candle A1 is consumed and the oxygen gas flow rate is lower than the minimum allowable value, the pressure switch p-sw closes;
At this time, the candle body is still hot and the thermal switch T-8W1 is closed, so current flows through the nichrome wire H2 and candle condition 2 is lit.

Thereafter, in the same way, when the combustion of candle A2 approaches the end, the pressure switch p-sw and the thermal switch T are turned on.
-8W2 are both closed and candle A3 is lit.

Note that the nichrome wire burns out after the candle is lit due to the high heat generated by the igniter, so even if the manual switch or thermal switch remains closed, it will not interfere with subsequent candle ignition.

Since the oxygen generator of the present invention has the sequential ignition mechanism as described above, the user does not need to perform any operation after igniting the first oxygen generator.

Furthermore, Kokichi uses a heat sensor that skillfully detects the heat generated by the oxygen generating body in addition to its unique logic, and the successive ignition mechanism is reliable, so anyone can use it with confidence.

In addition, the heat sensitive device eliminates the need to touch the thermal switch to the can wall every time the oxygen generator is replaced.
Moreover, since the thermal switch is surrounded by a foam block and a heat transfer piece, it is completely protected against water and heat from the outside, and has excellent durability and reliability.

[Brief explanation of the drawing]

Fig. 1 is a partially transparent perspective view of the heat sensor, Fig. 2 is a sectional view taken along line A-A' of the heat sensor in Fig. 1, fig. The figure is a schematic diagram of the pressure switch and its attached mechanism, and FIG. 5 is an electrical wiring diagram of the sequential ignition mechanism. Ll': heat transfer piece, 2: foam block, 3.3': thermal switch, 4: board, 5: mounting screw hole, 6: lead wire, 7: heat sensor, 8.8', 8'': chlorate candle, 9: pressure switch, 10: pressure chamber, 11: diaphragm, 12: rod, 13 niorifice, 14: bino, gas valve.

Claims (1)

[Scope of Claims] 1. An oxygen generator equipped with a plurality of chemical oxygen generators, which includes: (1) a metal heat transfer piece having a surface shaped so as to be in close contact with the oxygen generator can wall; (2) one side of the metal heat transfer piece; A foam block with rubber elasticity is fixed to the back side of the molded side of the heat transfer piece, and the other side is fixed to the substrate, respectively. The heat transfer piece of the heat sensor, which closes at a high temperature of A pressure switch is installed that closes when the temperature is reached, and the thermal switch of the heat sensitive device is connected in series with the pressure switch, so that when the oxygen generation from the oxygen generating body during combustion ends, it is in contact with the can wall of the oxygen generating body. 1. An oxygen generator comprising a sequential ignition mechanism in which an ignition voltage for an oxygen generator to be ignited next is supplied via a thermal switch and a pressure switch.