JPH0540797U - In-furnace monitoring device for vacuum induction melting furnace - Google Patents

Abstract

(57) [Abstract] [Purpose] In a vacuum induction melting furnace, etc., the inside of the furnace is monitored by a camera device, and the results are image-processed to accurately grasp the melting state in the furnace, and at the same time,
This is to eliminate the need for the in-furnace monitoring work that was conventionally performed by the operator's eyes. [Structure] A camera device 12 is set on a part of a viewing window 11 of a vacuum chamber 1. In this camera device 12, the camera device 12
The controller 13 for processing the image projected and input by is connected. The image processed by the controller 13 is displayed on the display device 14.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an in-furnace monitoring device in a vacuum induction melting furnace or the like for monitoring the melting state of a metal to be melted in the furnace body. Here, the induction melting furnace refers to a furnace in which an induction coil is wound around the outer periphery of the furnace body and the melting target metal is heated and melted by utilizing the principle of induction heating.

[0002]

[Prior Art]

 The vacuum induction melting furnace is a device for casting a molten metal into a mold by induction heating the metal to be melted in a vacuum or in an inert gas atmosphere. In addition, in order to put the metal to be melted into the furnace body, the method of taking out the furnace body from the vacuum chamber and setting the metal to be melted in the atmosphere, and the semi-continuous melting work There is a method of charging the molten metal into the furnace body without breaking the vacuum by using. Some induction melting furnaces of this type are equipped with an alloy addition device for adding a specific alloy to a molten metal in which a metal is melted.

After the metal to be melted is charged into the furnace body of this induction heating furnace and the melting is started by induction heating, the melting state of the metal to be melted and the unmelted metal remains in the furnace body. It is necessary to monitor the presence or absence of melted metal. In particular, if the phenomenon commonly referred to as "hanging" shown in Fig. 2 occurs, the problems described below will occur, so it is necessary to carefully monitor this. This "suspending" means that the molten metal is melted and the molten metal 23 is generated in the furnace body 22 due to the induction heating of the induction coil 21. This is a phenomenon in which the metal 24 remains, and the refractory crucible constituting the furnace body 22 is partially or entirely covered with the unmelted metal 24 to be melted. This "suspending" is caused by the shape of the metal 24 to be melted, the method of inserting the metal 24, and the like. If heating is continued without melting the melted metal 24 in the upper part in the hanging state, the temperature of the molten metal 23 and the refractory crucible in the lower part rises remarkably, and when the refractory crucible is damaged due to overheating, This will cause cracks in the refractory crucible and lead to an accident in which the molten metal leaks out.

Conventionally, in order to monitor the melting state of the metal to be melted and the above-mentioned hanging phenomenon, the operator visually observed it through a viewing window provided in the vacuum chamber. Therefore, the operator's restraint time is lengthened to monitor the dissolution status, and the judgment may be erroneous due to visual inspection. In addition, the method of visually monitoring the melting state of the metal to be melted by the operator hinders automation of the melting work in the vacuum induction melting furnace and labor saving.

[0005]

[Problems to be solved by the device]

 In view of the above situation, the present invention monitors the inside of a vacuum induction melting furnace with a camera device, and at the same time performs image processing of the result, the inside of the furnace can be monitored visually by an operator. The task was to make it unnecessary.

[0006]

[Means for Solving the Problems]

 In order to solve the above problems, the means adopted by the present invention is, in a vacuum induction melting furnace, a camera device for displaying the melting state of the metal to be melted in the furnace body in a vacuum chamber. Attached to the provided window part, connect to this camera device a controller for processing the image projected and input by the camera device, and further to this controller, the image processed by the controller. That is, a display device is connected to project the image.

[0007]

[Function of the device]

 The melting condition in the furnace is displayed by the camera device attached to the viewing window of the vacuum chamber, and this image is processed by the controller and displayed on the display device. I can grasp without. This eliminates the need for operator monitoring work, automates the melting work, and enables accurate operation of the melting process to ensure safe operation.

[0008]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to examples. First, the structure of the vacuum induction melting furnace will be briefly described, and then the in-furnace monitoring device A according to the present invention will be described in detail. In FIG. 1, a furnace main body 2 is installed inside a vacuum chamber 1, and the furnace main body 2 is tilted by a tilting device 3 so that the molten metal 4 inside is poured into a mold 5 for casting. It has become. The tilting device 3 of this example has a chain 3a whose one end is connected to the furnace body 2, a chain gear 3b on which the chain 3a is hooked to drive and rotate, and a chain 3a which is connected to the other end of the chain 3a. It is composed of a weight 3c for applying tension to the chain 3a. When the chain 3a on the side connected to the furnace body 2 is pulled by the driving rotation of the chain gear 3b, the furnace body 2 tilts counterclockwise about the fulcrum shaft 6 and the molten metal 4 inside Is poured into the mold 5. A raw material charging cylinder 7 for charging the molten metal into the furnace body 2 is provided above the vacuum tank 1 so as to project upward, and the raw material charging cylinder 7 shuts off the inside and outside of the vacuum tank 1. A valve 8 is provided for this purpose. Further, a viewing window 11 is provided in a cylindrical body portion 9 provided on the side of the raw material charging cylinder 7 in the upper part of the vacuum chamber 1. The cylindrical portion 9 is provided so as to be inclined, and its center line C intersects with the furnace body 2. In FIG. 1, reference numeral 10 denotes an induction coil arranged on the outer circumference of the furnace body 2.

Next, the reactor monitoring device A according to the present invention will be described. A camera device 12 is set on the view window 11 of the vacuum chamber 1, and the melting state of the metal to be melted contained in the furnace body 2 is displayed by the camera device 12. A controller 13 is connected to the camera device 12, and a monochrome gradation image projected by the camera device 12 is input and processed. In this embodiment, the black-and-white gradation image projected by the camera device 12 and input to the controller 13 is binarized so as to be converted into a black-and-white binary image corresponding to the degree of dissolution of the metal to be melted. It is configured. Of the metals to be melted, those that have been melted or heated to a specified temperature are displayed in white, and those that are not melted and that have not been heated to a specified temperature are displayed in black. If the image is composed of 512 × 480 pixels and each pixel is divided into white or black and binarized, the situation inside the furnace can be clearly understood. The black-and-white binary image binarized by the controller 13 as described above is displayed on the display device 14 connected to the controller 13. In this example, the image projected by the camera device 12 is converted into a monochrome binary image, but color image processing is also possible.

Therefore, the operator can grasp the melting state in the furnace accurately and quickly by reading the image displayed on the display device 14. That is, when the metal to be melted is melted or heated to a high temperature, the pixels that make up this part are displayed as "white" and are not melted or the temperature is low due to insufficient heating. When is low, the pixels forming this portion are displayed in “black”. As a result, when it is determined that the metal to be melted has been completely melted into a molten metal, the casting operation is started, and the power supplied to the induction melting furnace is switched from the melting power to the heat retention power. Can prevent overheating.

[0011]

[Effect of the device]

 According to the present invention, the inside of the vacuum induction melting furnace is monitored by a camera device, and the result is image-processed and displayed on a display device, so that the accurate melting state of the metal to be melted can be grasped at the same time. Since the work of monitoring the inside of the furnace, which was conventionally performed by the operator's eyes, can be eliminated, the work of melting can be saved. Since the accurate melting status of the metal to be melted can be grasped, it is possible to accurately judge the completely melted state of the metal to be melted, the presence or absence of "suspending", and to automate the melting work in the vacuum induction melting furnace. At the same time, safe operation becomes possible.

[Brief description of drawings]

FIG. 1 is a schematic view of a vacuum induction melting furnace equipped with a furnace monitoring device A according to the present invention.

FIG. 2 is a diagram for explaining a phenomenon of “suspending” of molten metal.

[Explanation of symbols]

 A: In-furnace monitoring device 1: Vacuum tank 2: Furnace body 4: Molten metal 11: Viewing window 12: Camera device 13: Controller 14: Display device

Claims (2)

[Scope of utility model registration request] 1. A vacuum induction melting furnace having a structure in which a furnace main body is installed inside a vacuum tank, and the molten metal melted in the furnace main body is poured into a mold to perform casting, which is provided in the vacuum tank. A camera device mounted on the part of the viewing window for displaying the melting state of the metal to be melted in the furnace body, and a camera device connected to this camera device and projected and input by the camera device. An in-furnace monitoring device in a vacuum induction melting furnace or the like, comprising a controller for processing an image and a display device connected to the controller for displaying the image processed by the controller. 2. The controller performs binarization processing for converting a black-and-white gradation image in the furnace projected and input by the camera device into a black-and-white binary image according to the degree of melting of the metal to be melted. The in-furnace monitoring device in the vacuum induction melting furnace or the like according to claim 1, which is performed.