KR960015213B1 - Making method and apparatus of bearing race - Google Patents

Abstract

This device includes continuous pre-heating furnace(20), high-frequency bar(30), dropping guard plate(40) of zigzag shape, feed conveyor(50)(60). This bearing race(10) provides a good crack prevention, and edge and surface(12) damage prevention of heat treated part(100) and tap hole(11), by setting several bearing races(10) in the upper direction of tap hole(11) on the feed conveyor(50), pre-heating the body of bearing race at 180 to 200deg.C, and continuous high frequency heating (annealing) the upper part with tap hole(11) by high frequency bar on the feed conveyor(60).

Description

Annealing Heat Treatment Method and Annealing Heat Treatment Apparatus for Inner Ring of UC Bearing

1 is a perspective view showing an example of an apparatus according to the present invention,

2 is a plan view showing a state in which the inner ring is advanced by the apparatus of FIG.

3 is a side view of a state in which the entire upper surface portion where the tab hole of the inner ring is located is heat-treated with a high frequency heater by the apparatus of FIG.

4 is a perspective view of the inner ring heat treated by the present invention.

* Explanation of symbols for main parts of the drawings

10: inner ring 11: tap ball

12 surface 20 continuous preheating furnace

30: high frequency rod 40: drop guide plate

50,60: Transfer conveyor 100: Heat treatment part

The present invention is an annealing heat treatment method and annealing heat treatment apparatus for uniformly preventing the tap hole portion of the inner ring body of a UC bearing (bowl bearing for rolling bearing unit: hereinafter referred to as "UC bearing") mainly used in the shaft portion of an industrial machine. In particular, the UC bearing inner ring can provide a uniform and high quality product while lowering the production cost of the UC bearing by increasing productivity by enabling an effective annealing heat treatment while moving a large amount of the inner ring together continuously. The present invention relates to a tab heat treatment annealing method and an annealing heat treatment apparatus.

In general, UC bearings installed on the shaft of industrial machinery refer to bearings whose type code is UC among bowl bearings for rolling bearing units. These UC bearings form tapped holes in predetermined portions of the inner ring to fix the inner ring. If the inner hardness of the tap hole outside the inner ring is high, cracks are easily generated in the tapping part of the inner ring after the fastening work of the inner ring or after fastening.

Therefore, in the case of UC bearings with tapped holes in the inner ring, the heat treatment around the tapped holes of the inner ring should be lowered to lower the hardness of the tapped holes. When the heat treatment is performed while the inner ring is not preheated during the annealing heat treatment around the tap hole, the inner ring body is cracked. Therefore, it is preferable to always preheat the annealing heat treatment before the annealing heat treatment.

However, in the related art, in the heat treatment for preventing the breakage of the tab hole portion of the inner ring body, the worker artificially heat-treated only locally on the tap hole portion of the inner ring body to perform the annealing process individually, in particular, the inner ring body weight. If the temperature difference between unannealed and unannealed areas is severe, group heat phenomenon occurs on the inner ring body. There was a problem that the productivity is low because it takes a long time.

In addition, even when working in a state of preheating a large amount of inner rings at a time by using a conventional preheating furnace, as described above, a worker manually picks inner rings of UC bearings with tongs one by one and individually contacts the heating rods of the heat treatment machine to perform manual work. Because the annealing heat treatment is performed, the working timing is different, so the temperature of the heat treatment in the preheated state of the inner ring is different, so the hardness of the inner ring is different after the annealing heat treatment. There is a problem of losing reliability.

In other words, when the annealing heat treatment is performed individually as described above, there is a problem in that the production cost is increased due to the decrease in the productivity and the manpower consumption compared to the working time, and in particular, the uniform annealing heat treatment cannot be performed to improve the quality. There was a problem that the relative competitiveness is low.

Therefore, the object of the present invention in view of the conventional problems as described above in the high-frequency heat treatment of the tap hole portion of the UC bearing, a large number of UC bearings in a continuous rapid and uniform automatic release heat treatment without individual heat treatment individually In order to reduce the production cost of bearings and to provide high quality uniformity and productivity of UC bearings, the present invention provides an annealing heat treatment method and an annealing heat treatment apparatus for the inner surface of UC bearings.

When described in more detail by the accompanying drawings of the present invention as a preferred embodiment as follows.

The annealing heat treatment method of the present invention first places a plurality of inner rings of the bearing in a zigzag on the transfer device so that the tab hole formed on the body is placed on the upper side, and then passes through the preheating furnace by the transfer device to preheat continuously. The preheating to a temperature of 180 ~ 200 ℃ that the hardness of the inner ring body does not fall, and then heat treatment by high-frequency heating the upper part of the inner ring body preheated up to the temperature is located as a whole, the present invention is the upper side of the body That is, it is necessary to include a tab hole, the present invention, because the entire upper side of the body, that is, the entire upper side of the body including the tab hole portion is heated uniformly with high temperature at the moment when passing through the bottom of the high-frequency rod, . Since it is heated uniformly, several inner rings can be heat treated faster and more uniformly at once.

In the annealing heat treatment apparatus of the present invention, a circulating transfer conveyor 50 is installed at the bottom of the preheating furnace 20 so that a plurality of bearing inner races 10 pass through the preheating furnace 20 continuously by the transfer conveyor 50. It is configured to be preheated while the outlet 21 of the outlet 20 of the preheating furnace 20 is configured to install a separate conveying conveyor 60 for transferring the inner ring 10 from the conveying conveyor 50 to transfer. It is.

And, the upper end of the conveying conveyor 60 is installed so that the high-frequency bar 30 of the high-frequency heater to a predetermined height so that the proximal portion of the inner ring 10 passing through the bottom surface is continuously heated at high frequency. At the end of the conveying conveyor 60, a zigzag-type drop guide plate 40 is installed to reduce acceleration and impact when the inner rings 10 fall, and the reference numeral 12 in the drawing indicates a product rod or the like. Letters are marked surface and (100) is the portion of the inner ring body heat-treated at high frequency.

The process of heat-treating the tap hole 11 part of the bearing inner ring 10 by the annealing heat treatment apparatus of the present invention formed as follows is as follows.

As shown in FIGS. 2 and 3, when the plurality of bearing inner rings 10 are placed on the conveying conveyor 50 so as to be positioned above and at the tap hole 11, the inner rings 10 are continuously passed through the preheating furnace 20. The whole body is preheated to a predetermined temperature by the continuous preheating operation of the preheating furnace 20. The preheating temperature may vary slightly depending on the thickness of the inner ring of the bearing, which is a standard product, but the hardness of the inner ring body is not reduced. It is preferable to maintain the temperature of 180-200 degreeC.

Then, in the preheated state, the inner ring 10 passing through the outlet 21 of the preheating furnace 20 is immediately transferred to the conveying conveyor 60, which is the next conveying means, and then conveyed to the lower part of the high frequency rod 30 of the high frequency heater. In this case, the inner ring (10) standing on the conveying conveyor (60) is passed through the bottom surface of the high-frequency rod 30 in the state that the tap hole (11) portion is all directed to the upper side as shown in FIG. The inner ring 10 is subjected to high heat generated from the high-frequency rod 30 as a whole only the upper end portion where the tap hole 11 is located, so that the full-room heat treatment is uniformly performed.

In addition, as described above, the plurality of inner rings 10, in which the tab hole 11 is effectively annealed by high temperature and high frequency, are continuously transported by the conveying conveyor 60, and then fall along the drop guide plate 40. When the inner ring 10 falls in a straight line, when the inner ring 10 falling due to acceleration and the inner ring 10 stacked on the floor collide with each other, the heat treatment of the upper end of the inner ring 10 which is not cooled due to the impact force If the part 100 is impacted and its edges are damaged, as well as the impact force is severe, there is a possibility that the surface 12 marked with letters such as product lots may be damaged.

However, since the drop guide plate 40 of the present invention is formed in a zigzag shape rather than a straight shape, as the inner ring 10 that falls falls in contact with the mouth wall of the drop guide plate 40 and falls into a zigzag, the acceleration at the time of falling is reduced as much as possible. As described above, the problem of the edge damage or the surface 12 of the heat treatment part 100 of the inner ring 10 can be solved.

In addition, as described above, by the spark generated during the annealing heat treatment by the high frequency, the peripheral edges of the heat treatment parts 100 of the inner ring 10 body are stuck to each other and fall to the drop guide plate 40. Since the falling guide plate 40 is formed in a zigzag shape, the inner ring 10 falls in the separated state at the moment of contact with the mouth wall of the falling guide plate 40 of the zigzag shape, and thus does not need to be separated.

As described above, in the present invention, the entire upper end portion of the inner ring body of the bearing where the tab hole is formed can be heat-treated more uniformly and rapidly in a large amount by high frequency, while improving productivity, and the edges or characters of the heat-treated portion can be improved. As it is possible to effectively prevent damage to the displayed surface, it is possible to keep the value of the product higher, and it is possible to keep the production cost of the bearing as low as possible while maintaining high quality uniformly, thereby increasing the competitiveness considerably.

Claims (2)

While passing through the preheating furnace 20 in a state in which a plurality of bearing inner races 10 are zigzag tightly attached to the conveying conveyor so that the tab hole 11 formed in the body is located at the upper part, all of the bearing inner rings 10 are placed therein. The inner ring 10 allows the body to be preheated to a temperature of 180 to 200 ° C., and the inner ring 10 that has passed through the preheating furnace 20 maintains a standing state as it is, and only the upper portion where the tab hole 11 is formed during the transfer process. An annealing heat treatment method for a tap hole portion of an inner ring of a UC bearing, which is subjected to an annealing heat treatment continuously by the high frequency heating. The inner ring 10 is transferred from the conveying conveyor 50 to the outlet 21 of the preheating furnace 20 in which the conveying conveyor 50 is installed so as to continuously pass a plurality of bearing inner rings 10 on the bottom. A separate conveying conveyor 60 is installed, and the upper part of the conveying conveyor 60 is installed with the high frequency bar 30 of the high frequency heater so as to cross a predetermined height so that the proximal portions of the inner rings 10 passing through the bottom surface thereof are disposed. Heat treatment device for loosening the tab hole portion of the inner ring of the UC bearing, characterized in that the high-frequency heating continuously, the zigzag-shaped drop guide plate 40 is installed at the end of the transfer conveyor (60).