JPH0536143Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Industrial Application Field) This device is attached to the journal of the axle,
This relates to an oil drain for an axle that comes into sliding contact with an oil seal lip. (Prior Art) As shown in FIG. The lubricating oil 8 is scraped up by the rotation of the rollers 9 and balls 10 and lubricates the entire bearing, and the lip of the oil seal 2 fixed to the axle box slides against the outer periphery of the oil sluice 1 assembled in the journal. Generally, the structure is such that the lubricating oil inside the axle box does not leak out. Since the axles of vehicles, especially Shinkansen trains, rotate at high speeds, the outer circumferential surface of the oil drain, which comes into sliding contact with the oil seal lip, is subject to significant wear. Japanese National Railway Standard (JRS)
According to 17931−2B−15AR8T, on the surface of the oil cutter
To combat wear, the surface was plated with a hardness of HV700 or higher, or induction hardened to make the surface harder to HV600 or higher. Furthermore, there are bearing devices in which the surface of the mating part that comes into sliding contact with the seal ring is coated with ceramic, and the sliding contact between the ceramic coating and the seal ring lowers the coefficient of wear and improves the wear resistance between the seal ring and the seal ring. (Akira Jitsuka
(See Publication No. 59-59572). (Problem to be solved by the invention) The reason why the outer circumferential surface of the oil cutter that makes sliding contact with the oil seal lip is worn out is due to the friction between the lip 12 of the oil seal 2 and the sliding surface 13 of the oil cutter 1, as shown in FIG. Dust 11 containing ceramics such as Al ₂ O ₃ and Si ₂ O ₃ enters between the layers as foreign matter, so these particles are harder than the hard chrome plating layer and cause the plating layer to form on the outer peripheral surface 12 of the oil drain. This causes further wear on the sliding surface of the oil cutter. For this reason, after peeling off the glazing layer each time the vehicle is inspected,
Since the inspection cycle for the entire vehicle was not extended, maintenance costs for the vehicle were high. Furthermore, it is also possible to coat the sliding surface of the oil drain with ceramics, but in this case, the adhesive strength of ceramics is usually about 60 to 100 Kgf/mm ² , and it is difficult to coat the sliding surface of the oil drain with For parts that are fitted with a large interference (0.150 to 0.200 mm) to the axle and are subjected to large vibration acceleration (50 to 100 G), applying a material with weak adhesive strength such as a ceramic coating layer will cause the thermal spray coating to peel off. There is a risk of (Means for solving the problem) This invention uses one or more types of titanium nitride, carbide, and carbonitride, which have greater adhesive strength than ceramics, on the sliding contact surface with the oil seal lip of the oil drainer. By coating the vehicle, the amount of wear is significantly reduced, repair costs are reduced, and vehicle inspection cycles are extended. (Function) When the axle rotates at high speed, the oil seal comes into contact at high speed with the sliding surface of the oil cutter coated with one or more of titanium nitrides, carbides, and carbonitrides. Since there is little wear, there is no cracking in the coating and the sealing effect is maintained for a long time. (Example) Next, an example of this invention will be described with reference to the drawings. FIG. 1 shows an axle box of a Shinkansen train to which this invention is applied, in which the journal 6 of the axle 4 is incorporated into the axle box 5 via a roller bearing 3, and the front cover 14 is further attached to the axle box 5. A ball bearing 7 is interposed between the shaft end and the shaft end, so that the axle shaft 4 can rotate relative to the axle box 5. Further, an oil drain 1 as shown in FIG. 2 is fitted on the side of the axle 4 where a wheel (not shown) is attached. A rear cover 15 is attached to the axle box 5 in correspondence with the above-mentioned oil drain. The rear lid faces the inner and outer peripheral surfaces of a cylindrical seal portion 16 provided on the outer periphery of the oil pan 1 with a gap therebetween, and also faces the outer peripheral surface of the rear lid with a gap therebetween to form a labyrinth seal gap. A seal portion 17 having a U-shaped cross section is formed. Further, an oil seal 2 is attached to the rear cover near the bearing, and two lips 12 extending inwardly and outwardly contact a sliding surface 13 on the outer periphery of the oil drain. oil seal 2
As shown in FIG. 2, a coating layer 23 of titanium nitride (TiN) is formed on the sliding contact surface 13 of the oil cutter, which the lip 12 of the oil slide contacts, to prevent wear even when the axle 4 rotates at high speed. is being processed. Furthermore, the outer ring 1 of the roller bearing 3 is located below the axle box 5.
9 and the raceway 24 of the outer ring 20 of the ball bearing 7 are filled with lubricating oil to the extent that the raceway 24 of the outer ring 20 of the ball bearing 7 is recessed.
As the axle rotates, the lubricating oil is scraped up by the rotation and revolution of the rollers 9 and balls 10, and the lubricating oil is scraped up from above.
The ball 10 and raceway surfaces 18 and 24 are lubricated. In addition to the above-mentioned TiN, the coating layer of the oil cutter may be formed by a single layer or a composite layer of titanium carbide (TiC) or carbonitride (TiCN) by appropriate means such as thermal spraying, if necessary. can. By the way, an oil seal lip was applied to the outer circumferential surface of a sample ring with an outer diameter of 40φ and an inner diameter of 19φ, one coated with TiN as in this invention, and the other with hard chrome plating like the conventional product. A comparative wear test was carried out by placing the two in contact with each other. A Test conditions

【table】

[Table] B Test Results The wear depth of each seal ring after the test was as shown in Figure 5. As shown, the amount of wear of the present invention was extremely small, approximately 1/10 compared to that of hard chrome plating. No oil leakage from the oil seals was observed in either case. (Effects) As mentioned above, this invention uses one or more types of titanium nitride, carbide, and carbonitride, which have a higher adhesive strength than ceramics at 600 kgf/mm ² , on the outer peripheral surface of the oil drain. Since it was coated, the wear resistance was dramatically improved. Further, even if the shaft is fitted with a large interference (0.150 to 0.200 mm) and subjected to large vibrational acceleration (50 to 100 G), there is no risk of cracking in the coating film such as the ceramic weld layer. This not only reduces the cost of repairing the sliding surface of the oil drainer, but also significantly extends the vehicle inspection cycle, which can also be expected to reduce vehicle maintenance costs.

[Brief explanation of drawings]

Figure 1 is a sectional view of the journal part of an axle to which this invention is applied, Figure 2 is a vertical side view of half of the oil drain, Figure 3 is a sectional view of the main part of the invention, and Figure 4 is the oil seal. FIG. 5 is a partial enlarged sectional view of the sliding contact portion between the lip and the oil cutter, and is a comparison diagram of wear between the present invention and a conventional product. 1... Oil drainer, 2... Oil seal, 5... Shaft box, 6... Journal, 12... Oil seal lip, 13... Oil drain sliding surface.

Claims (1)

[Scope of utility model registration request] The sliding contact surface with the oil seal lip that is fitted into the axle journal and extends from the axle box is coated with one or more of titanium nitrides, carbides, and carbonitrides, which have greater adhesive strength than ceramics. An axle oil drainer featuring: