JPH08296981A - Upper electrode connecting device - Google Patents

Abstract

PURPOSE: To make it possible to supply a proper torque responding to adding work with one rotary drive means by installing equipment which changes over the supply voltage of the rotary drive means so that both a fastening torque required when a new upper electrode is to be screwed in and a nipple fastening torque required when a device main body is to be removed, may be set independently. CONSTITUTION: When a new upper electrode 8 is aligned with an upper electrode 9 under operation and an upper electrode connecting device 1 is lowered gradually, a plurality of guide rods 5 will be inserted into a guide pipe 11 since the guide pipe 11 is installed to the top of an electrode holder 12 at the position responding to the guide rods 5. Then, a male screw 13 of a new upper electrode 8 is screwed into a socket of the upper electrode under operation and 220V voltage supplied by a rotary drive means 2 is reduced to 110V with a voltage change-over switch (for example, transformer). Since this construction makes it possible to supply proper fastening and a fastening torque with one rotary drive means independently, the structure is simple while assembly or maintenance is easily available.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric furnace used for melting and refining a metal material, in which, when the electrode of the electric furnace is consumed, a new upper electrode is added to the electrode in use in the electric furnace. The present invention relates to an upper electrode connecting device used in.

[0002]

2. Description of the Related Art In an electric furnace, since the upper electrode is always worn, it is necessary to add new electrodes one after another when the upper electrode is shortened to some extent. Since the work of connecting the upper electrode is a work at a high temperature and a large amount of dust and is performed on an electric furnace in an environment that is extremely inferior to human labor, there is a problem of reduced work efficiency and lack of safety. In addition, as the size of the electric furnace has increased, the diameter of the upper electrode has also increased, and tightening by manual work is difficult. Conceivable. Therefore, various proposals have been made to solve the above problems.

For example, in Japanese Unexamined Patent Publication No. 64-14890, a new upper electrode held by a rotatable upper clamp device provided in the main body of the device is lowered by an elevating device while being moved to the upper electrode in use. It is possible to tighten. Further, in Japanese Patent Publication No. 55-46036, when a new upper electrode is spliced with an upper electrode in use, a tightening torque is generated in the new upper electrode gripped by a nipple portion provided at a lower end of a motor drive. Further, the above motor drive is composed of a high-speed low-torque motor mechanism and a low-speed high-torque motor mechanism, so that the tightening torque is variable, and replenishment work that prevents problems such as breakage of the upper electrode and abnormal wear is mechanically possible. .

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the proposal of Japanese Patent No. 14890, an upper clamp device for the device body to grip a new upper electrode is provided with a rotation driving means for screwing the new upper electrode into the upper electrode in use, and at the same time the new upper electrode is screwed at the time of screwing. Since the lower clamp device for gripping is provided, the mechanism and structure are complicated, making assembly and maintenance difficult and
It had the drawback of high equipment costs.

Further, in the proposal of Japanese Patent Publication No. 55-46036, in order to make the screwing torque and tightening torque of the new upper electrode variable, the main body of the apparatus has a high speed low torque motor mechanism and a low speed high torque motor mechanism. And
Screw the new upper electrode into the upper electrode in use at high speed and low torque, and finally tighten at low speed and high torque to prevent problems such as falling off of the upper electrode.Furthermore, after adding work, tighten when screwing in. With the same loosening torque as the torque, the nipple portion provided on the main body of the apparatus is detached from the new upper electrode.

However, dust or the like may be trapped between the nipple portion and the female screw portion of the new upper electrode, so that when the new upper electrode is tightened, the apparatus main body is detached (the nipple provided in the main body of the apparatus). Since a larger torque is required when the part is loosened), there is a drawback that the tightening torque is overloaded. In addition, since the two torque motor mechanisms are provided, the weight of the apparatus becomes unnecessarily heavy, the structure becomes more complicated, assembly and maintenance become difficult, and the equipment cost increases. . Therefore, an object of the present invention is to provide an upper electrode connecting device having the features described below.

1. Without using a rotary drive means such as a plurality of torque motor mechanisms, and without using a special rotary drive means,
Appropriate tightening and loosening torques can be supplied according to the replenishment work by one rotation drive means. 2. Since tightening and torque can be set separately, tightening torque is not overloaded. 3. Since an appropriate torque can be supplied with a simple mechanism, assembly and maintenance are easy. 4. Since the additional work can be performed with an appropriate tightening torque, the additional work can be performed without trouble such as abnormal wear and breakage of the upper electrode.

[0008]

In order to achieve the above object, the present invention connects a lower end of a new upper electrode by screwing it to the upper end of an upper electrode in use held by an electrode holder of an electric furnace. In the upper electrode connecting device as described above,
A new upper electrode gripping nipple is attached to the tip of a rotatable shaft that is attached via a rotation drive unit, and a new upper electrode screwing tightening torque and nipple loosening torque when the device is removed can be set separately. In order to
It is characterized by having a device for switching the supply voltage of the rotation driving means.

[0009]

In the present invention, when the work of adding a new upper electrode to the upper electrode in use is performed, it is possible to supply the appropriate tightening and loosening torque according to the work content, so that the torque during tightening is overloaded. In addition to this, it is possible to add the upper electrode while preventing problems such as abnormal wear and breakage of the upper electrode. Further, since it has a simple structure, it can be easily assembled and maintained.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall perspective view showing an embodiment of the present invention,
The upper electrode connecting device 1 has moved to be positioned above the upper electrode 9 in use. 2A is an electric circuit diagram of the rotation driving means, and FIG. 2B is an explanatory diagram showing torque characteristics. 3 is a side view of FIG. 1, FIG. 4 is a side view of a state before the male screw portion 13 of the new upper electrode 8 is screwed into the female screw portion of the upper electrode 9 in use, and FIG. 6 is a side view showing a state in which the male screw portion 13 is screwed into the female screw portion of the upper electrode 9 in use, that is, a state in which the upper electrode is connected. FIG. FIG. 7 is a side view showing a state in which the upper end of the upper electrode 8 is gripped by a new lower electrode of the upper electrode 8, and FIG. FIG. 8 is a side view showing a state in which the lower electrode nipple portion 3 of the upper electrode connecting device 1 is opened and then the upper electrode connecting device 1 is rolled up.

As shown in FIGS. 1 and 3, an upper electrode connecting device 1 is hung by a hook 4 of an overhead crane, a rotary drive unit 2 is provided on an upper part thereof, and a lower part of the rotary drive unit 2 is connected via a connecting shaft. The structure is such that a new upper electrode 8 is lifted by the nipple portion 3, a plurality of guide rods 5 are provided around the lower portion of the main body 14, and the support plate 1 is positioned so as to be located in the middle of the guide rods 5.
5 is provided, and is constituted by a centering guide 6 horizontally installed so as to be vertically slidable on the lower end of the guide rod 5 by a rope 7 suspended on the support plate 15. As shown in FIG. 3, a new upper electrode 8 is used for the upper electrode connecting work.
Then, the upper electrode 9 in use is aligned, and the upper electrode connecting device 1 is gradually lowered. Here, the electrode holder 12
Since the guide pipes 11 are provided on the upper surface at positions corresponding to the plurality of guide rods 5 provided in the upper electrode connecting device 1, the guide rods 5 are inserted into the guide pipes 11 as they are lowered. .

Next, as shown in FIG. 4, the male screw portion 13 of the new upper electrode 8 is screwed into the socket portion of the upper electrode 9 in use. In the screwing operation, as shown in the electric circuit diagram in FIG. 2, the voltage of 220V supplied to the rotation driving means 2 is changed to 110V by the voltage switching device (for example, a transformer) 16, so that the rotation driving means 2 is rotated. It starts with the torque of the torque characteristic in FIG. Next, as the male screw portion 13 of the new upper electrode 8 is screwed into the female screw portion of the upper electrode 9 in use, the rotation speed of the rotation drive means 2 becomes smaller, and when the screwing is completed, the torque characteristic of FIG. Tightened with torque. The rotational reaction force generated at this time is received by the electrode holder 12 via the guide rod 5. In the present invention, since tightening can be performed with an appropriate torque, it is possible to perform replenishment work while preventing problems such as the upper electrode coming off or breaking.

FIG. 5 shows a state after screwing is completed. After the screwing is completed, the upper electrode connecting device 1 is detached from the new upper electrode 8. Therefore, the new upper electrode 8 and the upper electrode 9 in use are simultaneously lifted by the hook 4 of the overhead crane via the upper electrode connecting device 1. The electrode holder 12 is gripped and replaced from the upper end of the upper electrode 9 in use to the lower end of the new upper electrode 8 (FIG. 6), and the nipple portion 3 is inverted (FIG. 7). At this time, as shown in the electric circuit diagram in FIG. 2, a voltage of 220 V is supplied to the rotary drive means 2 and the rotary drive means 2 is released with a loosening torque (torque characteristic in FIG. 2).
Is started, and the nipple portion 3 is loosened and removed from the female screw portion of the new upper electrode 8. Since dust or the like may be caught between the nipple portion 3 and the female screw portion of the new upper electrode 8, the loosening torque (torque characteristic in FIG. 2) is the tightening torque (torque characteristic in FIG. 2). ) Set larger. Further, the upper electrode connecting device 1 is rolled up by the hook 4 of the overhead crane to complete the connection (FIG. 8).

[0014]

As described above, the present invention exhibits the following effects. Since it is possible to separately supply appropriate tightening and loosening torques with one rotation driving means without using a special rotation driving means, the structure is simple and the assembly and maintenance are easy. It can be easily controlled so that the tightening torque does not become overloaded. Since the additional work can be performed with an appropriate tightening torque, the additional work can be performed without trouble such as abnormal wear and breakage of the upper electrode.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing an embodiment of an upper electrode connecting device of the present invention.

FIG. 2 (a) is an electric circuit diagram of a rotation driving means, and FIG.
FIG. 6 is an explanatory diagram showing torque characteristics.

FIG. 3 is a side view of FIG.

FIG. 4 is a side view detailing a series of operating conditions according to the upper electrode connecting device of the present invention.

FIG. 5 is a side view showing a state in which the upper electrode of the present invention is connected.

FIG. 6 is a side view showing a series of operating conditions according to the upper electrode connecting device of the invention.

FIG. 7 is a side view showing another series of operating conditions according to the upper electrode connecting device of the invention.

FIG. 8 is a side view showing another series of operating conditions of the upper electrode connecting device of the invention.

[Explanation of symbols]

 1 Upper Electrode Connection Device 2 Rotational Drive Section 3 Nipple Section 4 Hook of Overhead Crane 5 Guide Rod 6 Centering Guide 7 Rope 8 New Upper Electrode 9 Upper Electrode in Use 10 Arm 11 Guide Tube 12 Electrode Holder 13 Male of New Upper Electrode Screw part 14 Main body 15 Support plate 16 Supply voltage switching device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mikinosaku Yasuo 46-59, Nakahara, Tobata-ku, Kitakyushu, Fukuoka Prefecture 46-59 Nippon Steel Corporation Machinery & Plant Division (72) Nobuhiro Hirotsu Tobata, Kitakyushu, Fukuoka 46-59, Nakahara, Shinjuku-ku, Nippon Steel Corporation Machinery & Plant Division

Claims (1)

[Claims] 1. An upper electrode connecting device for screwing and connecting a lower end of a new upper electrode to an upper end of a used upper electrode held by an electrode holder of an electric furnace, the device being suspended by a crane. A new upper electrode removable nipple part is rotatably provided on the main body via a rotation drive means, and a new tightening torque when screwing in the upper electrode and a loosening torque when the device main body is detached can be set separately. Therefore, the upper electrode connecting device is characterized by having a device for switching the supply voltage of the rotation driving means.