JPH0535312B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a seal structure for a lubricated bearing box.

Prior Art Various seal structures are applied to the shaft insertion part of oil-lubricated bearing boxes, etc., which have an oil bath inside, in order to prevent the lubricating oil inside the bearing box from leaking from the shaft insertion part. . Among these, the labyrinth seal maintains a non-contact state between the bearing box and the rotating shaft, so there is no frictional resistance, and it is suitable when the rotating shaft rotates at high speed. There was a problem in that it was not possible to prevent dirt from entering the bearing box, and it was also impossible to prevent lubricating oil from leaking from the inside of the bearing box to the outside of the bearing box.

Purpose This invention solves the above-mentioned problems in the conventional example, guarantees high-speed rotation of a rotating shaft, and prevents the intrusion of foreign matter from the outside into the inside of the bearing box and the leakage of lubricating oil from the inside of the bearing box to the outside. It is an object of the present invention to provide a seal structure for a lubricated bearing box that can prevent the above problems.

Overview This invention supports a rotating shaft in a bearing box via a bearing, and slides labyrinth seals on the inside of the bearing and on the outside of the bearing between the bearing box and the rotating shaft on both sides spaced apart from the bearing by a predetermined length. Equipped with a dynamic sealing member,
In a lubricated bearing box having an oil bath inside, the sliding sealing member is formed by fitting a felt seal with a slight interference between the rotating shaft and the rotating shaft. This is a seal structure for a lubricated bearing box characterized in that a contact surface having a predetermined axial width is initially hardened by abrasion and the distance between the contact surface and the rotating shaft is set to a value close to zero.

Embodiment An embodiment of the present invention will be described based on FIGS. 1 to 4. Reference numeral 1 denotes an oil-lubricated bearing box, and a lower half member 1a and an upper half member 1b are fastened together with bolts 2... The bearing 3 is held inside the bearing box 1 by a lower half member 1a and an upper half member 1b. At the inner bottom of the lower half member 1a, two deep bottom portions are provided on both left and right end surfaces of the bearing box 1 with the intermediate bearing support section in between.
An oil bath 4 that separates the upper half member 1b is formed.
Lubricating oil 6 supplied from the oil holes 5, 5 is received by this oil bath 4, and a part of the bearing 3 is immersed in this lubricating oil 6.

End seal rings 7, 7 are attached to the shaft penetrating portions on both left and right end surfaces of the bearing box 1, respectively. This end seal ring body 7 consists of a pair of split rings that are separately provided on the lower half member 1a side and the upper half member 1b side, and has a plurality of inward flanges 8 on the inner circumferential surface thereof. are provided at intervals. This inward flange 8
... forms a labyrinth with a plurality of outward flanges 10 provided on the circumferential surface of the rotating shaft 9 supported by the bearing 3, as shown in FIG. The lubricating oil 6 is prevented from flowing out of the box from the shaft penetrating portion.

A felt seal ring 11 is attached to the inner periphery of the outer end of the end seal ring 7.
1 prevents dust from entering into the bearing box 1 from the shaft penetrating portion and preventing oil from leaking outside the bearing box 1. FIG. 4 is an enlarged view showing the attached state of the felt seal ring 11, in which the felt seal ring 11 is fitted into the recessed step 7a formed on the inner peripheral edge of the outer end of the end seal ring 7, and the end seal The felt seal ring 11 is held by a seal cover 13 which is secured to the outer end of the ring body 7 by bolts 12. When installing the felt seal ring 11, it is set so that there is a slight tightening margin between it and the rotating shaft 9.
Due to the initial wear and hardening of the felt seal ring 11 during use, the gap with the rotary shaft 9 is reduced to zero, thereby increasing the effectiveness of preventing oil leakage and dust intrusion.

Vertically long openings 14, 14 are formed in the side wall of the lower half member 1a at the portions facing the deep bottoms of the oil bath 4, respectively. They are sealed by circular lid members 16, 16, respectively.

The cooling water supply pipe 15 is bent into a U-shape, and has a cooling water introduction end 15a and a cooling water discharge end 1.
5b penetrates the lid member 16 and protrudes to the outer surface thereof, and the pipe penetrating portion of the lid member 16 is treated to be watertight. Then, with the U-shaped non-end side of the cooling water supply pipe 15 inserted into the deep bottom of the oil bath 4 through the opening 14 of the lower half member 1a,
The lid member 16 is attached to the periphery of the opening 14 with bolts 17...
It is tightened and fixed. Periphery of opening 14 and lid member 1
A packing 18 is interposed between the opening 14 and the opening 14 in a watertight manner.

19... are bolts for tightening and fixing the end seal ring body 7 to the lower half member 1a and the upper half member 1b, 20,
Reference numeral 20 denotes an air breather provided in the upper half member 1b, which prevents an increase in the internal pressure of the bearing box 1 due to a rise in temperature.

Effects As described above, the present invention supports a rotating shaft in a bearing box via a bearing, and a labyrinth seal is provided inside the bearing between the bearing box and the rotating shaft on both sides at a predetermined distance from the bearing. In a lubricated bearing box that has a sliding sealing member on the outside and an oil bath inside, the sliding sealing member is formed by fitting a felt seal with a slight tightening margin between it and the rotating shaft. The contact surface of this felt seal with the rotating shaft having a predetermined width in the axial direction is initially abraded and hardened, and the distance between the felt seal and the rotating shaft is set to a value close to zero, so dust and In addition to maintaining sufficient sealing performance against rainwater, the lubricating oil in the oil bath inside the bearing is effectively sealed by the labyrinth seal even during high-speed rotation, and furthermore, during initial rotation, the contact surface of the felt seal is Since the value between 〓 and 〓 is close to zero, the rotational torque is small,
High speed rotation is not hindered.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the present invention, FIG. 2 is a partially cutaway vertical sectional view thereof, FIG. 3 is a plan view thereof, and FIG. 4 is a partially enlarged sectional view thereof. DESCRIPTION OF SYMBOLS 1...Bearing box, 1a...Lower half member, 1b...Upper half member, 3...Bearing, 7...End seal ring, 7
a... Concave stepped portion, 8... Inward flange, 9...
Rotating shaft, 10... outward flange, 11... felt seal ring, 12... bolt, 13... seal cover.

Claims (1)

[Claims] 1. A rotating shaft is supported in a bearing box via a bearing, and labyrinth seals are provided on the inside of the bearing and on the outside of the bearing between the bearing box and the rotating shaft on both sides at a predetermined distance from the bearing. In a lubricated bearing box that is equipped with a sliding sealing member and has an oil bath inside, the sliding sealing member is formed by fitting a felt seal with a light tightening margin between it and the rotating shaft, and this A lubricated bearing box characterized in that the contact surface of the felt seal having a predetermined axial width with the rotating shaft is hardened by initial wear and the distance between the felt seal and the rotating shaft is set to a value close to zero. Seal structure.