JP2001132760A - Seal mounting structure for revolving bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent separation between annular grooves and a contact face of a seal material caused by the moment load and the vibration of a revolving bearing part in the digging and the hoisting of a load, and prevent the seal from dropping out from the annular grooves, even if it is separated. SOLUTION: In this seal-mounting structure of a revolving bearing, annular grooves are formed on an outer peripheral surface of an inner ring and an inner peripheral surface of an outer ring of the revolving bearing, second grooves are respectively formed in the annular grooves to fit a seal material into the annular grooves and the second grooves, the seal material is provided with a cavity part on an approximately central part of its cross section for easily inserting the seal material into the annular grooves and the second grooves, and further a slit is formed between the cavity part and the inner peripheral surface or the outer peripheral surface of the seal material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal mounting structure for a slewing bearing of a civil engineering or construction machine such as a hydraulic shovel and a crane.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 9, an annular groove having a rectangular cross section is formed on an outer peripheral surface of an inner ring and an inner peripheral surface of an outer ring of a slewing bearing, and a sealing material is provided in an annular groove on an outer peripheral surface of the inner ring. The lip portion is fitted so as to abut against the lower surface of the outer ring or the inner peripheral surface of the outer ring of the slewing bearing, and a seal material is inserted into the annular groove of the inner peripheral surface of the outer ring. The upper surface or the outer peripheral surface of the inner ring is fitted so as to abut, and the abutting surface between the annular groove and the sealing material is bonded by an adhesive.

However, a moment load is applied to a slewing bearing of a hydraulic excavator or a crane at the time of excavation or lifting of a load, so that the contact surface between the annular groove bonded with the adhesive and the sealing material is separated, and the sealing material is removed. The grease filled for lubrication into the steel ball portion of the slewing bearing and the internal gear of the inner ring enters the contact surface between the annular groove and the seal material, and further peeling progresses. The problem arose.

In order to solve such a problem, attempts have been made to use an adhesive having a strong adhesive force or to increase the dimensional accuracy of the annular groove and the seal contact surface to prevent peeling. It is difficult to bond the entire circumference of the contact surface evenly, and even if it can be bonded evenly, peeling occurs due to the moment load during excavation and load lifting and vibration of the swing bearing as described above. It has been difficult to prevent the seal from coming out of the annular groove due to the force of pulling out from the annular groove.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has as its object to provide a contact surface between an annular groove and a seal member due to a moment load during excavation or lifting of a load or vibration of a swing bearing portion. It is an object of the present invention to provide a seal mounting structure for a slewing bearing, which can suppress the occurrence of peeling of the bearing and prevent the seal from coming out of the annular groove even if the peeling occurs.

[0006]

In order to achieve the above object, according to the present invention, an upper revolving structure is mounted on a lower traveling body via a revolving bearing so as to be revolvable, and an outer peripheral surface of an inner ring of the revolving bearing and an inner surface of an outer ring. An annular groove is formed on the peripheral surface, and a sealing material is fitted into the annular groove on the outer peripheral surface of the inner ring so that an outer peripheral end lip portion of the sealing material comes into contact with the lower surface of the outer ring or the inner peripheral surface of the outer ring of the slewing bearing. In a seal mounting structure for a swivel bearing, a seal material is fitted into an annular groove on an inner peripheral surface of an outer ring such that an inner peripheral end lip portion of the seal material is in contact with an upper surface of the inner race or an outer peripheral surface of the inner race. A second groove is formed in the annular groove on the inner surface of the outer ring, and a second groove is formed in the annular groove on the inner peripheral surface of the outer ring. And an annular groove on the inner ring outer peripheral surface and the outer ring inner peripheral surface. 2 grooves are formed on one side (upper or lower) of the annular groove, respectively, and the sealing material is formed so as to fit with the annular groove and the second groove on the inner peripheral surface and the outer peripheral surface of the outer ring, respectively. And an annular groove and a second groove formed on the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring are formed on both sides (upper and lower) of the annular groove, respectively, and the sealing material is formed on the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring. It is characterized in that it is formed so as to fit into the groove and the second groove. Further, the present invention is characterized in that an annular cavity is formed at a substantially central portion in cross section of the sealing material, and a slit is provided between the annular cavity and the inner peripheral surface or the outer peripheral surface of the sealing material. .

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an overall side view of a hydraulic shovel employing the present invention, and FIG. 2 is a sectional view of a slewing bearing according to an embodiment of the present invention. FIG. 3 shows a detailed cross section of the annular groove and the second groove of the slewing bearing according to the present invention, and FIG.
FIG. 4 is a cross-sectional view of a seal material fitted into the annular groove and the second groove formed on the outer peripheral surface of the inner ring of the slewing bearing according to the present invention.
(B) is a cross-sectional view of a seal material fitted into the annular groove and the second groove formed on the inner peripheral surface of the outer ring of the slewing bearing according to the present invention. FIG. 5 shows an annular groove and a second groove of another slewing bearing according to the present invention.
FIG. 6 is a cross-sectional view of a seal member fitted into the annular groove and the second groove of another slewing bearing according to the present invention. 7 shows a detailed cross section of the annular groove and the second groove of another slewing bearing according to the present invention, and FIG. FIG.

In FIG. 1, reference numeral 1 denotes a lower traveling body, on which an upper revolving body 3 is pivotably mounted via a revolving bearing 2. An attachment 4 is pivotally mounted on a front portion of the upper swing body 3 so as to be able to move up and down, and a counter weight 5 as a balance weight is mounted on a rear portion of the upper swing body 3.

In FIG. 2, reference numeral 6 denotes a pivot bearing mounting seat of the lower frame constituting the lower traveling body 1, and an inner ring 8 having an internal gear 7 is fixed to the pivot bearing mounting seat 6 by bolts. An outer ring 10 is rotatably mounted on the inner ring 8 via a steel ball 9, and a turning frame 11 constituting the upper turning body 3 is fixed to the outer ring 10 by bolts.

As shown in FIG. 3, an annular groove 8a is provided below the outer peripheral surface of the inner ring 8, and a second groove 8b is provided in the annular groove 8a. The second groove 8b may be provided on one side (above or below) of the annular groove 8a, or may be provided on both sides (up and down). And the annular groove 8
The seal material 12 is inserted and fitted into the second groove 8b and the second groove 8b. The outer peripheral end lip portion 12c of the seal member 12 abuts on the lower surface of the outer ring 10 or the inner peripheral surface of the outer ring 10 of the slewing bearing 2, and seals grease supplied to the steel balls 9 of the slewing bearing 2.

On the other hand, an annular groove 10a is provided above the inner peripheral surface of the outer race 10, and a second groove 10a is provided in the annular groove 10a.
b is provided. The second groove 10b may be provided on one side (upper or lower) of the annular groove 10a, or may be provided on both sides (up and down). And the annular groove 1
The sealing material 13 is inserted and fitted into the first groove 10a and the second groove 10b. The inner peripheral end lip portion 13c of the seal member 13 contacts the upper surface of the inner ring 8 or the outer peripheral surface of the inner ring 8 of the slewing bearing 2, and seals grease supplied to the steel balls 9 of the slewing bearing 2.

The seal members 12 and 13 are made of flexible stick-like or string-like rubber, and are inserted and fitted into the annular groove 8a and the second groove 8b of the inner race 8 as shown in FIG. The sealing material 12 to be combined has annular projections 12a and 12b fitted into the annular groove 8a and the second groove 8b, respectively, and the outer peripheral end of the sealing material 12 forms the lip portion 12c. Also, as shown in FIG.
The sealing material 13 inserted and fitted into the annular groove 10a and the second groove 10b has annular projections 13a and 13b fitted into the annular groove 10a and the second groove 10b, respectively. The inner peripheral end forms the lip 13c.

Annular cavities 12d and 13d are respectively formed at substantially central portions of the seal members 12 and 13 in cross section, and the annular groove 8a and the second groove 8b of the inner ring 8 and the annular groove 10a and the The insertion and fitting into the second groove 10b are facilitated. In particular, the hardness of the sealing members 12 and 13 is low, and the annular grooves 8a and 10a and the second grooves 8b and 1 can be easily formed without the annular cavities 12d and 13d of the sealing members 12 and 13.
0b if it is possible to fit in
13d is unnecessary, but the hardness of the sealing members 12 and 13 is high and the annular grooves 8a and 10a and the second grooves 8b and 10
b, when it is difficult to fit the sealing material 12,
It is necessary to provide the annular cavities 12d and 13d in 13.
And the processing of the annular cavities 12d and 13d is facilitated,
The annular grooves 8a and 10a of the inner ring 8 and the second groove 8
Slits 12e, 13e are provided between the annular cavities 12d, 13d and the inner or outer peripheral surfaces of the annular projections 12a, 13a to facilitate insertion into the annular projections 12b, 10b.

In the above embodiment, the annular groove 8
a, 10a are provided with substantially rectangular second grooves 8b, 10b, and the projections 12b, 13b of the sealing materials 12, 13 fitted into the second grooves 8b, 10b are also substantially rectangular. On the other hand, the embodiments of FIGS. 5 and 6 show the second grooves 8b ', 10b'
b 'is substantially triangular, and the projections 12b', 13 of the sealing members 12 ', 13' fitted into the second grooves 8b ', 10b'.
b ′ is also substantially triangular. 7 and 8
In the second embodiment, the second grooves 8b "and 10b" are provided in the direction in which the sealing members 12 and 13 are inserted in order to further prevent the sealing members 12 and 13 from coming out of the annular grooves.

Next, the operation of the present embodiment will be described. First,
The annular groove 8a (8a ', 8a ") of the inner ring 8 of the sealing material 12
And how to fit into the second groove 8b (8b ', 8b ") and the annular groove 10a (10a',
10a ") and the second groove 10b (10b ', 10b").
However, the hardness of the sealing material is low and the annular grooves 8a (8a ', 8a ") and 10a can be easily formed without the annular cavities 12d, 13d of the sealing materials 12, 13.
(10a ', 10a ") and the second groove 8b (8b', 8b).
b ") and 10b (10b ', 10b"), it is possible to use sealing materials 12, 13 without the annular cavities 12d, 13d, and the sealing materials 12 and 13 have high hardness and the annular groove 8a. (8a ′, 8a ″) and 10a (1
0a ', 10a ") and the second groove 8b (8b', 8b").
And 10b (10b ', 10b ") are difficult to fit into the annular cavities 12d, 13d and the slit 1
The sealing materials 12 and 13 having 2e and 13e are used.

The annular grooves 8a (8a ', 8a ") and the second grooves 8b (8b', 8b") provided below the outer peripheral surface of the inner ring 8 of the slewing bearing 2 and the inner peripheral surface of the outer ring 10 are provided. Is washed and the second groove 10b (10b ', 10b ") is washed, dried and then coated with an adhesive. Then, the stick-shaped or string-shaped sealing members 12 and 13 having flexibility are so arranged that the outer peripheral end lip portion 12c of the sealing member 12 abuts on the lower surface of the outer ring 10 or the inner peripheral surface of the outer ring 10 of the swing bearing 2. In addition, the sealing material 13
The annular groove 8a (8) so that the inner peripheral end lip portion 13c of the
a ', 8a ") and 10a (10a', 10a") and the second grooves 8b (8b ', 8b ") and 10b (10b',
10b "), and the end surfaces of the sealing members 12 and 13 are bonded to each other with an adhesive.

The projection 12b (12) of the sealing material 12
b ′, 12b ″) are provided on the lower surface of the inner ring 8 of the slewing bearing 2 below the second groove 8b (8b ′, 8b ″).
The protrusion 13b (13b ', 13b) of the sealing material 13
b ″) are fitted into the second grooves 10b (10b ′, 10b ″) provided above the inner peripheral surface of the outer ring 10 of the slewing bearing 2, respectively, and the movement in the horizontal plane is completely restricted.

In this embodiment, the protrusions 12b (12b ', 12b')
b ″), 13b (13b ′, 13b ″) are used to seal the outer peripheral surface of the inner ring 8 and the outer ring 1 of the orbiting bearing 2.
0 annular grooves 8a (8a ', 8a ") formed on the inner peripheral surface,
10a (10a ', 10a ") and the second groove 8b (8
b ′, 8b ″), 10b (10b ′, 10b ″), so that the seal does not come out of the annular groove, and an annular hollow portion is formed substantially in the center of the cross section of the seal material. Since the slit is provided between the annular hollow portion and the inner peripheral surface or the outer peripheral surface of the sealing material, there is an effect that the insertion into the annular groove and the second groove becomes easy.

The present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0020]

According to the present invention, separation occurs due to a moment load during excavation or lifting of a load or vibration of a swivel bearing portion, and a force for pulling the seal out of the annular groove acts to cause the seal to slip out of the annular groove. It has very remarkable effects such as disappearance.

[Brief description of the drawings]

FIG. 1 is an overall side view of a hydraulic shovel employing the present invention.

FIG. 2 is a sectional view of a slewing bearing according to an embodiment of the present invention.

FIG. 3 shows a detailed sectional view of an annular groove and a second groove of the slewing bearing according to the present invention.

FIG. 4A is a cross-sectional view of a seal material fitted into an annular groove and a second groove formed on the outer peripheral surface of the inner ring of the slewing bearing according to the present invention. (B) is a cross-sectional view of a seal material fitted into the annular groove and the second groove formed on the inner peripheral surface of the outer ring of the slewing bearing according to the present invention.

FIG. 5 shows an annular groove and a second groove of another slewing bearing according to the present invention.
2 shows a detailed sectional view of the groove of FIG.

FIG. 6 shows an annular groove and a second groove of another slewing bearing according to the present invention.
FIG. 3 is a cross-sectional view of a sealing material fitted into the groove of FIG.

FIG. 7 shows an annular groove and a second groove of another slewing bearing according to the present invention.
2 shows a detailed sectional view of the groove of FIG.

FIG. 8 shows an annular groove and a second groove of another slewing bearing according to the present invention.
FIG. 3 is a cross-sectional view of a sealing material fitted into the groove of FIG.

FIG. 9 shows a sectional view of a conventional slewing bearing.

[Explanation of symbols]

 2 Slewing bearing 8 Inner ring 8a (8a ', 8a ") Annular groove 8b (8b', 8b") Second groove 10 Outer ring 10a (10a ', 10a ") Annular groove 10b (10b', 10b") Second Groove 12 Sealing material 12a (12a ', 12a ") Projection 12b (12b', 12b") Projection 12c (12c ', 12c ") Lip 12d (12d', 12d") Annular cavity 12e (12e ', 12e ") Slit 13 Seal material 13a (13a ', 13a") Projection 13b (13b', 13b ") Projection 13c (13c ', 13c") Lip 13d (13d', 13d ") Annular cavity 13e ( 13e ', 13e ") slit

Claims (5)

[Claims] An upper revolving structure is mounted on a lower traveling body via a revolving bearing so as to be revolvable, and annular grooves are formed in an outer peripheral surface of an inner race and an inner peripheral surface of an outer race of the revolving bearing. A seal material is fitted into the annular groove so that the outer peripheral end lip portion of the seal material abuts on the lower surface of the outer ring or the inner peripheral surface of the outer ring of the slewing bearing, and the seal material is inserted into the annular groove on the inner peripheral surface of the outer ring. The inner peripheral end lip portion of the slewing bearing is fitted so as to abut the inner ring upper surface or the inner ring outer peripheral surface of the slewing bearing, and the annular groove of the inner ring outer peripheral surface and the outer ring inner peripheral surface has a second groove. Wherein the seal member is formed so as to fit into the annular groove and the second groove of the inner ring outer peripheral surface and the outer ring inner peripheral surface, respectively. 2. An annular groove and a second groove on the inner ring outer peripheral surface and the outer ring inner peripheral surface are formed on one side (upper or lower) of the annular groove, respectively, and the seal material is formed on the inner ring outer peripheral surface and the outer ring inner surface, respectively. The seal mounting structure for a slewing bearing according to claim 1, wherein the seal mounting structure is formed so as to be fitted into the annular groove and the second groove on the peripheral surface. 3. An annular groove and a second groove on the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring are formed on both sides (upper and lower sides) of the annular groove, respectively, and the seal material is formed on the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring, respectively. The seal mounting structure for a slewing bearing according to claim 1, wherein the seal mounting structure is formed so as to be fitted with the annular groove and the second groove. 4. The seal mounting structure for a slewing bearing according to claim 1, wherein an annular hollow portion is formed at a substantially central portion in a cross section of the seal material. 5. The slewing bearing according to claim 4, wherein a slit is provided between an annular cavity formed substantially at the center of the cross section of the sealing material and an inner peripheral surface or an outer peripheral surface of the sealing material. Seal mounting structure.