JPS6138213A - Gear transmission for grinder - Google Patents

Abstract

PURPOSE:To prevent fretting, by providing plural oil passages on a contact surface of a member facing to an outer race of a thrust bearing to thereby divide the contact surface sliding on the outer race into plural small slide contact surfaces. CONSTITUTION:A slide contact surface of a case 13 facing to an outer race 14b is entirely provided with plural lattice-like oil passages. Each size (l) of unit slide contact surfaces divided by the oil passages is set with respect to a relative slide amplitude (a) within the range of l-a<about 3. Thus, good lubrication may be obtained under a high surface pressure on the entire slide contact surface to greatly improve antifretting.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a gear transmission device for a vertical crusher for crushing solid materials such as coal.

[Background of the Invention] Conventionally, this type of gear transmission for a crusher receives an unbalanced thrust load from the crusher body, so a thrust load and a moment with an undefined direction are applied to the transmission output shaft, which causes the thrust There is a risk that fretting wear may occur between the thrust bearing that supports the load and members such as the gear casing that are in contact with the thrust bearing. As a means for preventing this fretting wear, the present applicant has proposed a method in which an oil groove is provided in a member that contacts the thrust bearing outer race to supply lubricating oil to the sliding surface. However, with this prevention means, the problem of how effectively oil grooves lubricate a sliding surface that is subjected to sliding vibration while being subjected to surface pressure has not been recognized. In other words, on a sliding surface, flat members are in close contact with each other and receive sliding vibration, and since the sliding motion is not large enough to draw oil from the oil groove to the sliding surface, it is not enough to simply provide several oil grooves. The lubrication condition of the sliding surface was not improved at all, and there was a problem in that the oil film ran out and fretting wear progressed, just as in the case without oil grooves.

[Purpose of the invention]

The purpose of the present invention is to improve the lubrication state of the outer race of the thrust bearing and the sliding surfaces of the members that are in contact with the outer race of the thrust bearing in a gear transmission for a crusher, and to prevent fretting wear, thereby achieving a highly reliable and long service life. An object of the present invention is to provide a gear transmission device for a crusher.

[Summary of the invention]

In the conventional example, the sliding surface was lubricated by providing an oil groove in the member of the sliding surface, but actual machines and experiments have shown that the sliding surface is not lubricated due to the excessive oil groove, and fretting progresses. confirmed. Therefore, in order to minimize the size of each sliding surface and shorten the distance from the oil passage, we created a large number of oil passages that divided the entire sliding surface into small sections.
The size of each small sliding surface (RIa) is the relative sliding amplitude (
It has been found that when Ω-a < 3 for the cylinder (a), effective lubrication of the sliding surfaces can be achieved and fretting wear can be prevented.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an outline of a ball-shaped crusher main body. It consists of a pressure cylinder 6 that applies pressure to the ball 4 via an upper ring 2 and a lower ring 3, and the lower ring 3 is connected to a gear transmission bag W5 via a coupling 7. FIG. 2 shows details of the gear transmission bag N5, including an input shaft 8 that is integrated with a bevel gear, a helical small gear shaft 10 that has a critical gear 9 that meshes with it, and a helical large gear 11 that meshes with the small gear. The three rotating bodies of the output shaft 12 fitted with the output shaft 12 are assembled in the case 13.
is connected to the crusher main body 1 via a coupling 7 and supported by a thrust bearing 14 and a radial bearing 15. A thrust bearing 14 that supports the thrust load from the crusher main body 1 is installed between the Haspa large gear 11 and the case 13. Figure 3 shows the details of the structure of the thrust bearing 14 section, and shows the thrust bearing inner race 1.
4a is fitted onto the output shaft 12 and supports the nozzle large gear 11, and the outer race 14b is installed on the case 13. , 16 are a large number of oil passages provided on the surface of the case 13 that is in contact with the outer race 14b, as shown in FIGS. The lubricating oil 17 that has been
is supplied to the sliding surfaces of the outer race 14b and the case 13. The details of the shape of the oil passage are shown in FIGS. 4 and 5. Reference numeral 619 indicates a sliding surface. In the pulverizer gear transmission 1 configured as described above, driving force from a prime mover (not shown) is transmitted from an input shaft 8 to a medium-thick gear 9. Helical small gear 1
0. It is transmitted to the helical gear 11 and rotates the lower ring 3 of the crusher main body from the output shaft 12 via the coupling 7, thereby causing the balls 4 between the upper ring 2 and the lower ring 3 to roll. At this time, the balls 4 are rolled under pressure by the pressurizing cylinder 6 through the upper ring 2 and the lower ring 3, so that the coal inserted between the upper ring 2 and the lower ring 3 is crushed. . This thrust load is applied from the lower ring 3 of the crusher main body 1 to the thrust bearing 14 via the coupling 7 and the output shaft 12, and is supported by the case 13.

However, when coal is severely pulverized in the pulverizer main body 1, the pulverization conditions in each ball 4 are different, so the thrust load varies depending on the position of each ball. As shown in FIG. 2, a large unbalanced load (arrow B in the figure) is applied to the device 5 in addition to the main thrust load (arrow A in the figure). Because of the moment of this unbalanced load, the thrust bearing 1
4 outer race 14b and the case 13 facing it
Since the rollers make small relative movements in the radial direction while supporting the main thrust load, there is a risk that severe fretting wear will occur, especially on the surface of the case 13 side. In the present invention, as shown in FIG. 4, oil passages are provided in a grid pattern over the entire sliding surface of the case 13 that is in contact with the outer race 14b, and the size of each unit sliding surface divided by the oil passages is 1f ( m+
+) is the relative sliding amplitude value a(nw
By setting 11-a < 3 with respect to o), it is possible to achieve good lubrication of the entire sliding surface under high surface pressure, and it is possible to dramatically prevent fretting resistance. In a conventional gear transmission with a simple oil groove, the oil in the oil groove is not drawn into the sliding surface on the sliding surface 19, which vibrates against each other under high surface pressure, and the oil in the oil groove is not drawn into the sliding surface, as in the case without an oil groove. Fretting progresses rapidly. According to experiments by the inventors.

It has been confirmed that according to the present invention, the amount of wear due to fretting is approximately 1/30 to 1/40 of that of the conventional method.

Figure 6 shows the size Q of each small sliding surface divided by the oil passage 16, the sliding amplitude aIIIn, and the amount of wear (expressed as an index).
This schematically shows the relationship between the following: If Qa is large, severe wear will occur regardless of the size of the sliding surface, but if the size Q of each vehicle sliding surface becomes small to a certain extent, Wear resistance improves rapidly.

7 and 8 show a large amount of oil and water 2 on the surface of the case 13.
This shows another embodiment of the present invention in which 0 is provided, and if the size of each unit sliding surface is set to the relationship Qa<3, the same effect as described above can be achieved.

FIG. 9 shows still another embodiment of the device of the present invention,
In FIG. 9, 18 is a spacer that is removably provided in the case 13 so as to be in contact with the thrust bearing outer race 14b.The oil passage 16 as described above is provided on the surface of this spacer 18, and the sliding surface is It is finely divided.

When the spacer 18 is provided in the case 13 in this way, not only can fretting wear be prevented as described above, but also the oil passage can be easily machined, and replacement work during maintenance can be easily performed.

〔Effect of the invention〕

According to the present invention, the reliability of the gear transmission is greatly improved by enabling effective lubrication between the thrust bearing outer race and the member in contact therewith, and preventing fretting wear occurring in the member. and can extend the lifespan.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram for explaining the main body of the pulverizer, Fig. 2 is a longitudinal cross-sectional view of the gear transmission device for the pulverizer of the present invention, Fig. 3 is a detailed view of the thrust bearing section in the apparatus of the present invention, and Fig. 4 The figure is a detailed view showing the oil passage in the device of the present invention, Figure 5 is a sectional view taken along the line ■-■ in Figure 4, and Figure 6 is the relationship between the size of the /11 sliding surface, the sliding amplitude, and the amount of wear. , FIG. 7 is a detailed view showing another embodiment of the device of the present invention, FIG. 8 is a sectional view taken along the line ■-■ in FIG. 7, and FIG. 9 is another embodiment of the device of the present invention. FIG. DESCRIPTION OF SYMBOLS 1...Crusher main body, 2...Upper ring, 3...Lower ring, 5...Gear transmission, 8...Input shaft, 1
2...Output shaft, 13...Case, 16...Oil passage, 18...Sube Figure 3, 4 Port, right diagram, 6 Port, 7th, 8th fixing? 0

Claims (1)

[Claims] 1. In a gear transmission device for a pulverizer in which a pulverizer main body for pulverizing solid materials such as coal is placed on the upper side, an outer race of a thrust bearing that supports a fluctuating thrust load of the pulverizer main body A gear transmission device for a crusher, characterized in that a large number of oil passages are provided on the surfaces of opposing members, and a sliding surface with the outer race is divided into a large number of small sliding surfaces. 2. Claim No. 2, characterized in that the size (lmm) of the small sliding surface has a relationship of la<3 with respect to the relative sliding amplitude (amm) of the sliding surface. The gear transmission device for a crusher according to item 1. 3. The gear transmission for a crusher according to claim 1, wherein the member that contacts the lower surface of the thrust bearing outer race is a lower gear casing. 4. The gear transmission for a crusher according to claim 1, wherein the member that contacts the lower surface of the thrust bearing outer race is a spacer.