JPH04121588A - In-furnace monitoring device for continuous electrical furnace - Google Patents

Abstract

PURPOSE:To perform a positive sensing of an abnormal state generated in a passage in a furnace chamber by a method wherein when a light signal advancing in the passage is shielded, and an occurrence of abnormal state in the passage in the furnace is detected. CONSTITUTION:A light signal composed of a straight forwarding laser beam generated from a light emitting device 14 is received in a light receiving device 15 if there is no abnormal state in a passage 3. The light signal is comprised of a laser beam, for example, and its light passing passage is set to pass below a lower end 4a of a spaced-apart wall brick 4 placed at the most suspended position in the passage. This laser beam L passes over a baked item 12 mounted on a table plate 11 and is set at such a position of height not providing any trouble in movement of the baked item 12. If it is assumed that the spaced-apart brick 4 within the passage 3 is hung down due to an aging caused by heat or vibration or the like and the lower end 4a of the spaced-apart brick descends at the position where the laser beam L is shielded, the laser beam L is shielded by the spaced-apart brick 4. Accordingly, the light receiving device 15 does not receive any light signal from the light emitting device 14. Due to this fact, it is detected by an input signal of the light receiving device 15 that there has occurred an abnormal state in the passage 3.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an in-furnace monitoring device for monitoring the safety in the furnace of a continuous electric furnace.

(Prior Art) In general, continuous electric furnaces heat the furnace chamber with a heating means such as a heater, so they are characterized in that no combustion gas is generated and there is little heat loss.

Then, the base plate is conveyed through a tunnel-like straight path by a pusher, etc., and the object to be fired on this plywood is preheated, fired,
It is fired after going through processes such as cooling.

In such a continuous electric furnace, the furnace walls and ceiling are made of firebrick or the like.

(Problem to be solved by the invention) However, in conventional continuous electric furnaces, in order to make the atmosphere and temperature distribution uniform in the length direction inside the furnace, heat and atmosphere are moved through the furnace using partition walls from the ceiling. It is divided to make it smaller. For this reason, the refractory bricks may fall or become misaligned due to repeated thermal contraction and expansion of the refractory bricks due to temperature changes within the furnace. If the misalignment of the refractory bricks, especially the ceiling bulkhead bricks, becomes large, the object to be fired placed on the plywood moving in the straight-line passageway of the furnace chamber may collide with the bulkhead bricks, or the bulkhead bricks may fall into the passageway. If such a situation occurs, there is a problem that the object to be fired may be damaged or the furnace itself may be damaged or collapsed.

To solve this problem, conventionally the inside of the furnace was regularly observed from the entrance, but the entrance was narrow to avoid heat loss, and the space between the bulkhead bricks and the products to be fired was narrow inside. , it was not possible to carry out sufficient monitoring.

The present invention provides a device for constantly monitoring the inside of a continuous electric furnace that reliably detects abnormalities occurring in the passage of the furnace chamber extending in a straight line in order to confirm the safety inside the furnace. The purpose is to

(Means for solving the problem) For this purpose, the in-furnace monitoring device for a continuous electric furnace of the present invention has the following features:
A furnace body made of a refractory material, a passage extending in a straight line for moving objects to be fired in the furnace, and a floodlight that is provided at the entrance or exit of this passage and generates a straight beam of light;
and a light receiver provided at the exit or entrance of the passageway to receive the optical signal generated by the light emitter, and when the optical signal traveling through the passageway is interrupted, an abnormality occurs in the passageway in the furnace. It is characterized by detecting that

(Function) According to the in-furnace monitoring device for a continuous electric furnace of the present invention, an optical signal is received from the light projector to the light receiver during normal operation.

When the optical signal from the light emitter is cut off, the optical receiver will not receive the optical signal, so it is detected that an abnormality has occurred in the passage within the furnace.

(Example) Embodiments of the present invention will be described below based on the drawings.

A schematic diagram of an in-furnace monitoring device for a continuous electric furnace to which the present invention is applied is shown in FIG. 1, and specific examples are shown in FIGS. 2 to 4.

The continuous electric furnace 1 has, for example, a total length of 30 m.

FIG. 2 shows the section from the inlet section 1a to the outlet section 1b, with a part of the intermediate section omitted. In FIG. 2, a continuous electric furnace 1 has a passage 3 extending linearly into a furnace body 2 for moving the object to be fired.

As shown in FIGS. 3 and 4, the furnace body 2 is constructed by stacking a large number of refractory bricks 16 of various shapes and scorches in the side walls and ceiling of the furnace.

A-A shown in FIG. 2 near the inlet part 1a of the continuous electric furnace 1
The ceiling of the cross section is lower than the ceiling of B-B on the downstream side to prevent heat dissipation at the entrance.

Also, C- on the downstream side of the B-B cross section of the continuous electric furnace 1.
The C section extends so that the lower end 4a of the partition brick 4 from the ceiling constitutes the ceiling position of the passage 3 in order to reduce the movement of heat and atmosphere in each section of the furnace. A hole 5.6 is opened in the side wall of the furnace to communicate between the outside of the furnace and the inside of the furnace.
A heater 7.8 is inserted into the passage 3, and the inside of the passage 3 is heated by this heater 7.8.

In this embodiment, the product is heated from above and below, but in the present invention, the heaters may be arranged so as to heat the product from the left and right sides. An object to be fired 12 placed on a base plate 11 on a floor surface 10 of the passage 3 is moved within the passage 3 by being pushed by a pusher or the like.

A light projector 14 is provided at the inlet portion 1a of the continuous electric furnace 1, and a light receiver 15 is provided at the outlet portion 1b of the continuous electric furnace 1. An optical signal consisting of a straight laser beam or the like generated from the light projector 14 is received by the light receiver 15 if there is no abnormality in the passage 3.

The optical signal is composed of, for example, a laser beam, and the path of the light is directed to the lower end 4 of the partition wall brick 4 at the lowest hanging position in the passage.
It is set so that it passes below a. This laser beam passes above the object to be fired 12 placed on the base plate 11, and is set at a height that does not interfere with the movement of the object to be fired 12.

If the partition brick 4 in the passageway 3 sags due to changes over time due to heat, vibration, etc., and the lower end 4a of the partition brick falls to a position where it blocks the laser beam, the laser beam is blocked by the partition brick 4. Therefore, the receiver 15 is the emitter 14
does not receive optical signals from. Therefore, the occurrence of an abnormality in the passage 3 is detected by the input signal of the light receiver 15.

In the embodiment described above, the passage position of the laser light connecting the light emitter 14 and the light receiver 15 was set below the partition wall brick 4, but in the present invention, the light emitter and the light receiver are set so that the laser light passes through the side of the passage. It is also possible to set the position.

In addition, as another example, in order to observe changes in the partition wall bricks in the width direction inside the furnace, a projector and a light receiver can be installed at two or three locations so that the light beam passes in the width direction of the furnace, and the furnace length can be moved horizontally. It can also be supported.

Furthermore, in order to detect changes in the downward hanging of the partition bricks within the furnace, it is also possible to provide a light projector and a light receiver that can be moved up and down.

In the present invention, it is preferable to position the projector and the light receiver so that the laser beam passes through a position where it is considered that there is no problem in passing the base plate and the object to be fired through the linearly extending passage. Further, by providing light refracting means such as a prism for refracting laser light at the entrance and exit of the furnace, the space at the entrance and exit of the furnace can be effectively utilized.

(Effects of the Invention) As explained above, according to the in-furnace monitoring device for a continuous electric furnace of the present invention, the light beam is blocked because it is configured to pass a light beam that is straight through a passage extending in a straight line. This has the effect of being able to reliably detect the occurrence of an obstruction in the passageway and quickly and accurately confirming the safety inside the reactor.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an in-furnace monitoring device of a continuous electric furnace according to an embodiment of the present invention, FIG. 2 is a longitudinal cross-sectional view showing a continuous electric furnace according to an embodiment of the present invention, and FIG. A- in the diagram
A half cross-sectional view of Al1 and B-B wire numbers, FIG. 4 is C-C, I! in FIG. 2! FIG. 1...Continuous electric furnace, 2...Furnace body (refractory material) 3...Passage, 12...Object to be fired, 14...Light emitter, 5...Light receiver.

Claims (1)

[Claims] (1) A furnace body composed of a refractory material, a passage extending in a straight line for moving the object to be fired in the furnace, and a passage provided at the entrance or exit of this passage to generate a straight beam of light. The method includes a light projector and a light receiver that is provided at an exit or an entrance of the passage and receives an optical signal generated by the light projector, and when the optical signal traveling through the passage is interrupted, an abnormality occurs in the passage in the furnace. An in-furnace monitoring device for continuous electric furnaces that detects the occurrence of.