JPH0129676Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a thermal fire detector that uses optical fiber, and uses the light of the optical fiber to light up an alarm indicator when heat from a fire is detected. Regarding type fire detectors.

Conventionally, thermal fire detectors are installed between a pair of power and signal wires, and when they receive heat from a fire, the heat-responsive part of the thermal fire detector changes state to open a contact that is always open. Closed to short-circuit the power and signal lines. This short circuit causes current to flow between the power and signal wires, so the receiver knows that the thermal fire detector has triggered an alarm due to this current flow, and determines that there is a fire. In addition, the power supply/signal line is provided with an alarm indicator lamp for a thermal fire detector, so that it emits light when a current flows therethrough. This allows people in the vicinity of the fire detector to know that the fire detector has triggered an alarm. By the way, thermal fire detectors with electrical contacts as described above are extremely dangerous when used in places filled with explosive gas such as oil complexes, or in explosion-proof areas where open flames are strictly prohibited. I can't. Therefore, a thermal fire detector using an optical fiber has been proposed as a thermal fire detector without electrical contacts. This thermal fire detector using optical fiber is configured to allow light to pass through the optical fiber at all times, and a heat-receiving/responsive part that receives heat from the fire intercepts the light from the optical fiber. . However, such thermal fire detectors using optical fibers have a problem in that it is not possible to know which thermal fire detector has triggered the alarm. In addition, it is extremely dangerous to install an electrically connected alarm indicator light to identify whether the sensor has triggered an alarm or not, and to use it in a place filled with explosive gas or in an explosion-proof area. It had some problems.

This idea was created in view of the above problems.
When heat due to a fire is detected, the light from the light emitting optical fiber is received by the alarm display optical fiber, which notifies the receiver side of heat detection, and also lights up the alarm indicator light. It is possible to identify whether a sensor has triggered an alarm, and it can be used without danger in a place filled with explosive gas or in an explosion-proof area, and furthermore, the light from the light-emitting optical fiber can be used effectively. The present invention provides a thermal fire detector.

In order to achieve the above object, the present invention includes a light-emitting optical fiber that guides and radiates light from a light source, a light-emitting optical fiber that receives the light from the light-emitting optical fiber, and a light-emitting optical fiber that receives heat from a fire and becomes a heat-receiving responsive part that changes the light-emitting optical fiber and prevents the light from the light-emitting optical fiber from being received by the light-emitting optical fiber;
an alarm display optical fiber that receives light from the light emitting optical fiber at one end when the state of the heat receiving and responsive part changes; and an alarm display optical fiber that receives light at one end of the alarm display optical fiber and radiates the light to the outside at the other end. The present invention provides a thermal fire detector characterized in that it is configured with an alarm display section that causes a fire alarm to occur.

Embodiments of the present invention shown in the drawings will be described below. The thermal fire detector of the present invention shown in each drawing includes a light-emitting optical fiber 2 that guides and emits light from a light source (not shown), and a light-receiving optical fiber 3 that receives the light from the light-emitting optical fiber 2. and a heat receiving response section 5 that receives heat from a fire to change its state and prevents the light from the light emitting optical fiber 2 from being received by the light receiving optical fiber 3, and the state of the heat receiving response section 5. It is composed of an alarm display optical fiber 4 which receives the light from the light emitting optical fiber 2 at one end and radiates the light to the outside from the other end when the light emitting optical fiber 2 changes.

In FIGS. 1 to 3, the light emitting optical fiber 2 and the light receiving optical fiber 3 are installed in the sensor body 1 with their proximal ends facing each other. Further, the alarm display optical fiber 4 has its base end connected to the light emitting optical fiber 2 within the sensor main body 1.
Alternatively, it is located near the light-receiving optical fiber 3 and is attached with its tip communicating with the outside of the main body 1.

In FIG. 1, the heat receiving/responsive section 5 is constructed by connecting a diaphragm 9 to an air chamber 8 consisting of a mounting base 6 and a heat sensitive plate 7. That is, a diaphragm 9 is fixed from the inside to an air chamber 8 of a sealed structure formed by fixing the peripheral edges of the mounting base 6 and the heat-sensitive plate 7 to the main body 1 with an adhesive, and a support rod is attached to the diaphragm 9. The proximal ends of the light emitting optical fibers 2 are connected via 10.

Since the sensor shown in FIG. 1 is constructed as described above, when the heat-sensitive plate 7 receives heat from a fire, the air in the air chamber 8 sealed by the heat-sensitive plate 7 and the mounting base 6 expands, and the diaphragm Push up 9. By this pushing up, the light emitting optical fiber 2 switches the irradiation of light from the light receiving optical fiber 3 to the warning display optical fiber 4 via the support rod 10 of the diaphragm 9 with the fixing part 11 as an axis.

In this embodiment, the light-emitting optical fiber 2 is activated, but the light-receiving optical fiber 3 and the warning display optical fiber 4 are provided integrally, and the integrated optical fibers 3 and 4 are The light may be switched in response. Further, the optical fiber 4 for warning display may be made of transparent resin. In FIG. 1, the light receiving optical fiber 3 and the alarm display optical fiber 4 are fixed by a fishing support 12. As shown in FIG.

In FIG. 2, the heat receiving/responsive part 5 includes an inverted bimetal 14 provided inside a heat collecting plate 13, a leaf spring 15 fixed to the main body 1, and a support rod 16 provided at the tip thereof attached to a light emitting optical fiber 2. It is connected to the proximal end of. Since the heat receiving/responsive part 5 shown in FIG. 2 is constructed as described above, when it receives heat from the heat collecting plate 13, the inverted bimetal 14 is inverted and pushes up the leaf spring 15 through the protrusion 17, and by this pushing up. , the support rod 16 switches the direction of light irradiation from the light emitting optical fiber 2 to the light receiving optical fiber 3 to the alarm display optical fiber 4.

The heat receiving response section 5 in FIG. 3 includes a heat collecting plate 13,
The use of an inverted bimetal 14 and a leaf spring 15 is the same as that shown in FIG. 2, but a mirror 18 is provided at the tip of the leaf spring 15. That is, when the leaf spring 15 is pushed up by the inverted bimetal 14, this mirror 18 protrudes to block the optical path of the light-emitting optical fiber 2, as shown in FIG. optical fiber 2
The light is reflected and irradiated onto the alarm display optical fiber 4. In the case of using this mirror 18, since the optical fiber itself is not moved, it is preferable that the optical axis does not shake.

Basically, it is sufficient that the start alarm display section 19 of each of the above-described alarm display optical fibers 4 is made to protrude to the outside of the main body 1. On the other hand, as shown in Figure 5,
It is also possible to cover the alarm display section 19 with a glove 20 to diffuse light so that the alarm display can be more clearly identified.

The light used for the optical fibers in each of the above embodiments is visible light, infrared light, or the like. When using infrared light, the converting phosphor is attached to the glove 2 above.
It can be converted into visible light by applying it to the inside of 0.

As described above, the present invention has a structure in which the optical path is changed so that when the state of the heat receiving responsive part changes, the light from the light emitting optical fiber can be received from the light receiving optical fiber to the alarm display optical fiber. When heat due to a fire is detected, the receiver side is notified of the heat detection and an alarm indicator light is turned on to accurately identify which sensor has triggered the alarm. Moreover, since the heat detection and alarm display are performed using light, it can be used without danger in places filled with explosive gas or in explosion-proof areas. Furthermore, since the light for the alarm display uses light from the light emitting optical fiber, the light can be used effectively and the sensor structure can be easily constructed.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a thermal fire detector showing an embodiment of the present invention, Fig. 2 is a longitudinal sectional view of another embodiment, Fig. 3 is a longitudinal sectional view of yet another embodiment, and Fig. 4 is a longitudinal sectional view of a thermal fire detector showing an embodiment of the present invention. The figure is the third
FIG. 5 is an enlarged view of the main part of the figure, and FIG. 5 is an enlarged view of the alarm indicator light section. 1... Main body, 2... Optical fiber for light emission, 3...
Optical fiber for light reception, 4... Optical fiber for alarm display, 5... Heat reception response section, 19... Alarm display section, 2
0...Glove.

Claims (1)

[Scope of utility model registration request] A light-emitting optical fiber that guides and emits light from a light source, a light-emitting optical fiber that receives the light from the light-emitting optical fiber, and a light-emitting optical fiber that receives heat from a fire to change its state and emit the light from the light-emitting optical fiber. a heat-receiving response section that prevents light from being received by the light-emitting optical fiber; an alarm display optical fiber that receives light from the light-emitting optical fiber at one end when the state of the heat-receiving response section changes; 1. A thermal fire detector characterized by comprising an alarm display part that irradiates light received at one end of an alarm display optical fiber to the outside at the other end.