JPS6284256A - Automatic fire extinguisher for bath boiler of gas burning type - Google Patents

Abstract

PURPOSE:To provide a device compact and inexpensive in its construction for automatically extinguishing gas fire at a point of time where hot water reaches a predetermined temperature by using a shape memory alloy as an actuator. CONSTITUTION:When a bath burner is ignited, hot water the temperature of which is raised, makes contact with a drive element 26 in a cylinder 18 via a through hole. When the hot water temperature reaches a transformation point (set at 43 deg.C, for example) of a shape memory alloy, the drive element 26 which has been in a compressed state restores the memory of the expanded state and expandsat once. Upon this occasion, since the adsorptive force of a variable joint 34 is larger than a force required for rotating an operating lever 30, said joint 34 is not slipped, and both operating rods 36 and 38 integrally move downward to actuate to rotate an operating lever 30 clockwise. Thus, the gas in the bath burner is automatically extinguished by the rotation of the operating lever 30.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an automatic fire extinguishing system for gas baths, and more particularly, a driving element made of a shape memory alloy connected to an operating lever for controlling gas ignition and extinguishing is connected to a gas bath. placed inside,
This invention relates to an automatic fire extinguishing system configured to automatically extinguish a gas bathtub installed outdoors by transforming and moving the drive element in response to a rise in water temperature and operating the lever in the extinguishing direction.

BACKGROUND OF THE INVENTION There are various types of gas baths used in homes, such as a balance type and an instantaneous water heater type, but at present, the most widely used type is one in which the bathtub is installed outdoors. In this outdoor type gas bath, the bath kettle is installed adjacent to the outside of the bathroom, and the ignition and extinguishing of the gas is controlled via a cable connected to the gas cock using an operating lever located inside the bathroom.
It is designed to be controlled remotely.

Problems to be Solved by the Invention In the above-mentioned outdoor gas bath, after filling the bathtub with water, the control lever inside the bathtub is turned manually to ignite the ignition, but the water boils and reaches the appropriate temperature. It was necessary for one person to put out the gas fire after the bath was heated, and therefore it was necessary to frequently inspect the bath while it was being heated and to constantly monitor the level of water. In this case, there are already devices in existence that detect the temperature of the boiling water using a sensor and sound a buzzer when the temperature reaches a predetermined temperature to alert householders that the water is boiling.

However, a mechanism for automatically extinguishing gas by rotating the operating lever in the extinguishing direction at boiling temperature has not yet been put into practical use because the motor and other actuators for energizing the lever are large and expensive. do not have.

However, the inventor of the present application proceeded to consider how to solve the problem of automatically extinguishing the outdoor gas bath, and found that the recently developed shape memory alloy as a functional material has a transformation point in a predetermined temperature range. We focused on the fact that its form and behavior change significantly, and the energy released during this change is sufficient to rotate the operating lever in the extinguishing direction.

Using this, we have devised the automatic fire extinguishing system of the present application.

To briefly explain shape memory alloys, this alloy is made of, for example, an alloy of nickel and titanium, and after being given a desired shape, the austenite transformation end temperature (Af
By applying shape memory treatment to heat above the humidity temperature,
It is a metal material that has the unique property of memorizing the shape given to it by metallographic structure before heat treatment. Therefore, even if deformation is applied within a predetermined stress range, it will instantly recover to its original shape by simply heating it to a temperature slightly higher than the temperature at the time of deformation.

In view of this unique property of remembering the original shape, various applications in various industrial fields have been proposed. For example, seal joints for hydraulic pipes in aircraft are made using a shape memory alloy that is slightly smaller than the pipe diameter at room temperature, and after expanding the diameter of this joint at temperatures below zero, it is fitted onto the pipes to be joined. A very tight pipe connection is made by inserting the tube and then leaving it at room temperature to recover its original shape. Furthermore, since the shape changes in response to temperature changes, there are applications such as use as a drive source for opening and closing a damper of a cold air outlet of a cooler or the like.

Purpose of the Invention The present invention is based on the above-mentioned outdoor gas bath, in which an effective means for automatically extinguishing the gas after the water has boiled has not yet been developed, and the temperature of the water must be constantly monitored. In view of the inconvenience of having to manually extinguish gas, this was proposed to solve this problem.
It is an object of the present invention to provide a structurally simple and inexpensive device that automatically extinguishes gas when a predetermined water temperature is reached by using a shape memory alloy as an actuator.

Means for Solving the Problems In order to solve the above-mentioned problems and suitably achieve the purpose, the present invention provides a method for turning on and off the ignition and extinguishing of a bathtub installed outdoors by rotating an operating lever facing the top of the bathtub. An apparatus for use in a gas bath configured to be operated by the bathtub 12.
fixing means 10 fixable to the bottom 12a or side of the
An actuator 25 using a drive element 26 made of a shape memory alloy is connected to the fixing means 10, and an actuating rod 22 whose one end is connected to the actuator 25 and whose other end is pivoted to the operating lever 30. It is characterized by being composed of.

Another invention of the present application which can achieve the above-mentioned object in the same manner is used in a gas bath configured to turn on and off a bathtub installed outdoors by rotating an operating lever facing above the bathtub. The apparatus comprises: a bottom part 1 of the bathtub 12;
2a or the side thereof; an actuator 25 using a drive element 26 made of a shape memory alloy connected to the fixing means 10; and an actuator 25 connected to the actuator 25 and extending upward. a first actuating rod 36; and a second actuating rod 36 whose one end is pivotally connected to the operating lever 30 and whose other end is connected to the first actuating rod 36 via a variable joint 34.
It is characterized by comprising an actuating rod 38.

Embodiments Next, the automatic fire extinguishing system for gas baths according to the present invention will be described below with reference to preferred embodiments and the accompanying drawings. The device according to the embodiment is used in a gas bath configured to turn on and off the ignition and extinguishing of a bathtub installed outdoors by rotating an operating lever facing the top of the bathtub. The operating lever is configured to extinguish the gas in the position shown in FIG. 1 and to ignite the gas by rotating it counterclockwise to the position shown in FIG. 2.

In the figure, reference numeral 10 indicates fixing means that can be detachably fixed to the bottom 12a of the bathtub 12.

As the fixing means 10, a hemispherical vacuum cup made of synthetic rubber is preferably used. A rod member 14 is attached to the pin 1 at the top of the fixing means 10 consisting of the vacuum cup.
6, and is pivotably mounted so as to be oriented upward.

The upper end of this rod member 14 is screwed and connected to the bottom plate 18a of a cylindrical body 18 whose top and bottom are closed, as shown in an enlarged view in FIG.

The top plate 18b of the cylindrical body 18 has a through hole 2 at its center position.
0 is bored through the through hole 20, and an actuating rod 22 connected to an operating lever to be described later is slidably inserted into the cylindrical body. A disk 24 having a diameter approximately equal to the inner diameter of the cylinder 18 is slidably disposed inside the cylinder 18, and this disk 24 is attached to the actuating rod 24 inserted into the cylinder through the through hole 20.
It is screwed and fixed to one end 22a of the. Further, the cylindrical body 18 houses a driving element 26 in which a wire rod made of the shape memory alloy described above is wound in a cylindrical spiral shape at a predetermined pitch. This driving element 26 can take an extended state as shown in FIG. 1 and a compressed state as shown in FIG. 2, and the shape in the extended state is memorized at the manufacturing stage. shall be. When the cylindrical spiral driving element 26 is housed in the cylindrical body 18 in its extended state, the upper end 26a of the driving element 26 is located inside the cylindrical body 18.
The lower end portion 26b contacts the inner surface of the top plate 18b, and the lower end portion 26b
is adapted to come into contact with the disk 24 located on the bottom plate 18a side in the cylindrical body 18. Note that the cylinder body 18 is provided with a through hole 28 for introducing hot water in the bathtub 12 into the interior.

The operating rod 22 extends above the bathtub 12, and its upper end 22b is pivotally connected via a pin 32 to an operating lever 3o that rotationally controls gas ignition and extinguishing of the bathtub. In this case, it is preferable that the upper end 22b of the actuating rod 22 be pivotally connected to a portion relatively close to the base 30a of the operating lever 30, taking into account the strokes of the drive element 26 during expansion and compression. .

The above is the basic structure of the primary invention of the present application, and as will be described later, gas is automatically extinguished at a required hot water temperature. When the temperature of the water drops during a refreshing bath and it is necessary to ignite the gas again, the drive element 26 becomes open due to the hot water, making it difficult to rotate the operating lever 30 in the ignition direction. .

To deal with this, the embodiment shown in FIGS. 3 to 5 is provided with a variable joint 34, but the other configurations are exactly the same as those shown in FIGS. 1 and 2. For example, the actuation rod is divided into a first actuation rod 36 and a second actuation rod 38. Then, the drive element 2
4, a first actuating rod 36 is connected at its upper end 3
6a, it is connected to one plate magnet 40 constituting a variable joint 34 (described later) shown in FIG. Further, the second operating rod 38 whose upper end is pivotally connected to the operating lever 30 is connected at its lower end 38a to the other plate magnet 42 constituting the variable joint 34.

Here, the variable joint 34 usually integrally connects the first actuating rod 36 and the second actuating rod 38, and means that a force in a pulling direction or a pushing direction of a predetermined value or more acts on the variable joint 34. The members that allow the relative movement of both rod members 36 and 38 are referred to as . In the illustrated example, the variable joint 34 uses two rectangular plate magnets 40 and 42 of equal size. A long hole 44 of a predetermined width is bored in each of the plate magnets, and both plate magnets 40 and 42 are magnetically attracted with opposite polarities, and a bolt 46 is commonly inserted into the long holes 44 and 44. is slid through the magnet to prevent both magnets from separating. Therefore, when a force above a certain level acts on either of the plate magnets 40, 42, the plate magnets 40, 42 slip against this attraction force, causing the first actuating rod 36 to slip.
and the second actuating rod 38 can be moved away from each other or toward each other. Further, as will be described later, the magnitude of the magnetic attraction force in the double plate magnets 40 and 42 constituting the variable joint 34 is such that when the drive element 26 is kept at room temperature and in a soft state, the operating lever 30 is rotated. The drive element 26 is set to such an extent that it does not slip even when the operating lever 30 is rotated, and when the drive element 26 is heated and in the open state, it slips when the operating lever 30 is rotated.

In the above embodiments, the means for fixing the device of the present invention to the bottom or side of the bathtub is on the side of a hemispherical synthetic rubber vacuum cup; It may also be a weight, a magnet (if the bathtub is made of magnetic metal), etc., as long as it can be attached.
Alternatively, the bathtub may be fixed with a C-link or the like using a hole that communicates the bathtub with the bathtub.

Further, elastic members such as springs can also be suitably used as long as they have the characteristics shown in this embodiment.

Furthermore, the cylindrical body in the present invention may be composed of two plates and a plurality of round bars.

Next, the actual use of the automatic fire extinguishing system for gas baths according to the present invention will be explained. Since the devices shown in FIGS. 1 and 2 and the devices shown in FIGS. 3 to 5 have most of the same behavior, the device provided with the variable joint 34 will be described. Further, FIG. 8 is a diagram showing changes in the properties and expansion and contraction state of the shape memory alloy, the state of the variable joint, and the ignition and extinguishment state of gas as the temperature of the water in the bathtub changes over time.

Prior to use, the fixing means 10 consisting of a vacuum cup is suctioned and fixed to the bathtub bottom 12a located directly below the operating lever 30, and the upper end of the second operating rod 38 is connected to the operating lever 3° in the gas extinguishing position. It is pivoted to. In this state, the drive element 26 in the cylinder 18 is in an extended state, as shown in FIG. It is in contact with the inner surface of 18a. After setting up this device in this way,
2. Supply water to a predetermined level. At this time, the shape memory alloy that constitutes the drive element 26 is.

It comes into contact with room temperature water that enters through a through hole 28 formed in the cylindrical body 18 and becomes soft.

When igniting the bathtub, a force is manually applied to the operating lever 30 in a counterclockwise direction as shown in FIG. 4. At this time, since the drive element 26 is in a flexible state, both operating rods 36, 3
8 is pulled up integrally without causing the variable joint 34 to slip, allowing rotation of the operating lever 30 and igniting the gas. Note that the drive element 26 is compressed as shown in FIG.

When the bathtub is ignited, the water in the bathtub 12 rises with the temperature gradient shown in FIG. are in contact. The temperature of the hot water is the transformation temperature of the shape memory alloy (e.g. 43°C).
3), the drive element 26 which was in the compressed state recovers its memory of the extended state shown in FIG.
- It has grown rapidly. At this time, the adsorption force of the variable joint 34 is:

Since the force is greater than the force required to rotate the operating lever 30, the joint 34 will not slip, and both operating rods 36 and 38 will move upward as a unit to rotate the operating lever 30 clockwise. The state shown in FIG. 3 is restored. That is, the gas in the bathtub is automatically extinguished by rotating the operating lever 30.

Thus, according to the basic embodiment of the invention, the bathtub 12
After the hot water inside reaches the required temperature, gas extinguishing is carried out automatically, relying on the properties of the shape memory alloy, without relying on human intervention.

Note that when the temperature of the water drops during bathing and it is necessary to ignite the gas again, the drive element 26 is in the closed state in contact with the hot water, so in the device shown in FIGS. 1 and 2, the operating lever 30 Even if an attempt is made to rotate the drive element 26 in the ignition direction, the drive element 26 remains in the extended state, making it difficult to re-ignite.
If the fixing means 10 is operated forcibly, it is expected that the fixing means 10 will separate from the bathtub bottom 12a). In order to deal with this situation, in the embodiment shown in FIGS. 3 to 5, the variable joint 34
is the provision. That is, when the bather operates the lever 30 in the drive element 26 in the tensioned state as shown in FIG. 5 and rotates it counterclockwise, the variable joint 3
4 slips with a force smaller than the tension force of the drive element 26, so the second actuating rod 38 is slidably displaced with respect to the first actuating rod 36.

By allowing the lever to rotate, the gas can be easily re-ignited (see FIG. 8).

In addition, if the water temperature rises due to relighting during bathing, it is necessary to extinguish the gas, but in this case, the bather must manually press lever 3.
0 in the extinguishing direction.

At this time, the first actuating rod 36 is moved as shown in FIG.

Since the disk 24 provided at the lower end of the disk 24 contacts the cylindrical bottom plate 18a and cannot descend any further, the variable joint 34, which has already been displaced, slips again in the restoration direction. The system returns to the state shown in Figure 3, extinguishes the gas, and waits for the next ignition.

In addition, after taking a bath, the temperature of the water drops and the water becomes cold, or after the water in the bathtub is drained, the shape memory alloy is cooled and becomes soft.

As described above, according to the automatic fire extinguishing device for a gas bath according to the present invention, a shape memory alloy is used as a driving element, and by appropriately setting the temperature transformation point of the driving element, the hot water in the bathtub can be brought to a desired temperature. Gas can be extinguished automatically after the gas has risen to a certain temperature without relying on human intervention. Moreover, since the structure is simple, the operation is reliable and the manufacturing cost can be kept low.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are explanatory diagrams showing the schematic configuration of a basic embodiment of the automatic fire extinguishing system for a gas bath according to the present invention in a usage state, and FIG. 1 shows the drive element being extended; The gas is shown extinguished, and FIG. 2 shows the driving element compressed and the gas ignited. Third
5 to 5 are explanatory diagrams showing a schematic configuration of the automatic fire extinguishing device for a gas bath according to the present invention in a developed form so that it can be re-ignited during bathing, and FIG. 6 is a connecting portion of a drive element. Fig. 7 is an enlarged view showing an example of a variable joint;
FIG. 8 is a diagram showing changes in the properties and expansion/contraction state of the shape memory alloy, the state of the variable joint, and the ignition and extinguishing state of gas as the water temperature in the bathtub changes over time. 10... Fixing means 12... Bathtub L2a...
Bathtub bottom 22... Operating rod 26... Drive element
30... Operating lever 34... Variable joint 36
...First operating rod 38...Second operating rod FIG, 1 FIG, 2 Procedural amendment (method) February 27, 1985 Michibe Uga, Commissioner of the Patent Office 1, Indication of case 1985 Patent Application No. 223232 2, Title of the invention: Automatic fire extinguishing system for gas baths 3, Relationship with the case of the person making the amendment Patent applicant address: 66 Kawide, Hoshizaki-cho, Minami-ku, Nagoya Name (
371) Daido Steel Co., Ltd. Representative Director Aki 1) Masaya 4, Agent 460 Address 5-3-11-6 Sakae, Naka-ku, Nagoya Subject of amendment (1) Drawing (Fig. 8) 7, Contents of amendment (1) Attached sheet

Claims (7)

[Claims] (1) A device used in gas baths configured to turn on and off the ignition and extinguishing of a bathtub installed outdoors by rotating a control lever facing the top of the bathtub, which is installed at the bottom or side of the bathtub. a fixing means that can be fixed; an actuator that uses a drive element made of a shape memory alloy and connected to the fixing means; and an actuator that has one end connected to the actuator and the other end pivoted to the operating lever. An automatic fire extinguishing device for a gas bath characterized by comprising a rod. (2) The gas bath according to claim 1, wherein the drive element is made of a shape memory alloy wire rod, which is wound in a cylindrical spiral shape and has shape memory in the stretched state. Automatic fire extinguishing system. (3) The actuator is configured such that the driving element is housed in a cylindrical body in an extended state, and one end thereof is brought into contact with the top of the cylindrical body, and the actuating rod is arranged in the cylindrical body to accommodate the driving element. 3. The automatic fire extinguishing system for a gas bath according to claim 1 or 2, wherein the fixing means is engaged with the other end and further connected to the cylindrical body via a rod member. (4) A device used in gas baths configured to turn on and off a bathtub installed outdoors by rotating a control lever facing the top of the bathtub, the device being installed at the bottom or side of the bathtub. a fixing means that can be fixed; an actuator connected to the fixing means and using a drive element made of a shape memory alloy; a first actuating rod connected to the actuator and extending upward; and one end connected to the operating lever. 1. An automatic fire extinguishing system for a gas bath, characterized in that the second operating rod is pivotally mounted at one end and the other end is connected to the first operating rod via a variable joint. (5) The gas bath according to claim 4, wherein the drive element is made of a shape memory alloy wire rod, which is wound in a cylindrical spiral shape and has shape memory in the stretched state. Automatic fire extinguishing system. (6) The actuator is configured such that the drive element is housed in a cylindrical body in an extended state and one end thereof is brought into contact with the top of the cylindrical body, and the first actuating rod is disposed within the cylindrical body. 6. The automatic fire extinguishing system for a gas bath according to claim 4, wherein the fixing means is engaged with the other end of the driving element and further connected to the cylinder body via a rod member. (7) The variable joint is made up of two plate magnets, and the plate magnets are arranged so that their polarities are opposite to each other so that they are magnetically attracted to each other. An automatic fire extinguishing system for a gas bath according to any one of claims 4 to 6, wherein bolts are commonly slidably inserted.