JPH11351267A - Bearing fixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing device of a bearing capable of double-locking a nut to fix the bearing. SOLUTION: A nut 29 to fix a bearing 13 is fitted between a carrier 22 coupled with a spline 23 provided on a tip part of a rotary shaft 12 and the bearing 13. A lock plate 31 to be engaged with the spline 23 is provided on an upper surface of the nut 29, and the lock plate 31 is tightened to the nut 29 by a bolt 30. A recessed part 22a to store the lock plate 31 is provided on an end part on the nut side of the carrier 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing fixing device for a planetary gear reduction mechanism of a turning device such as a hydraulic shovel or a crane.

[0002]

2. Description of the Related Art FIG. 7 shows an example of a hydraulic excavator.
Is mounted so as to be freely rotatable. The turning room 3 of the upper turning body 2 includes a machine room 4, a cab 5, and a counterweight 6.
The working device 7 is attached to the front of the revolving frame 3 so as to be able to descend.

In Japanese Utility Model Laid-Open Publication No. 3-130917, a spline is provided at the tip of a small-diameter portion of a shaft having a large-diameter portion fitted with a bearing, and the spline is provided between the mounting component fitted to the spline and the bearing. There is disclosed a bearing fixing device in which a bearing is fixed by a nut and a screw for screwing the nut is provided in a large diameter portion where the spline is cut up.

Next, a conventional swivel device shown in FIGS. 8 and 9 will be described. An inner wheel 8 a of a turning wheel 8 is fixed to the lower traveling body 1, and a lower flange of a housing 9 and an outer wheel 8 c of the turning wheel 8 are attached to the turning frame 3. An inner gear 8b is provided on the inner ring 8a. A ring gear 10 provided with a two-stage internal gear is attached to the upper flange of the housing 9, and a hydraulic motor 11 is installed above the ring gear 10.

[0005] An upper bearing 13 and a lower bearing 14 for supporting the pinion shaft 12 are attached to the inner peripheral wall of the housing 9. The pinion 15 provided at the lower end of the pinion shaft 12 meshes with the internal gear 8 b of the turning wheel 8.

A sun gear 17 constituting a planetary gear reduction mechanism G is attached to an output shaft 16 of the hydraulic motor 11. In the ring gear 10, a plurality of planetary gears 18, a carrier 19, a sun gear 20, a plurality of planetary gears 21, and a carrier 22 that are linked to the sun gear 17 are provided. The carrier 22 is connected to the upper end of the pinion shaft 12 via a spline 23.

The rotation of the output shaft 16 is transmitted from the sun gear 17 to the planetary gear 18. The planetary gear 18 revolves while rotating around the inner periphery of the ring gear 10, and the revolution is transmitted to the sun gear 20 via the carrier 19. . And the sun gear 20
The planetary gear 21 revolves around the inner circumference of the ring gear 10 while rotating, and the revolution is transmitted from the carrier 22 to the pinion shaft 12 via the spline 23. As described above, the rotation of the hydraulic motor 11 is reduced by two stages by the planetary gear reduction mechanism G, and is transmitted to the pinion shaft 12 as a high torque rotation.

When the pinion shaft 12 rotates, the pinion 15 revolves while rotating on the inner periphery of the revolving wheel 8, and the revolution is transmitted from the pinion shaft 12 to the revolving frame 3 via the housing 9, and The revolving superstructure 2 performs a revolving operation on the undercarriage 1.

The pinion shaft 12 is provided on the upper small diameter portion 1.
2a and a lower large-diameter portion 12b are formed in a stepped cylindrical shape. The above-described upper bearing 13 includes an inner ring 13a fitted to the small diameter portion 12a of the pinion shaft 12, an outer ring 13b attached to a mounting step of the housing 9, and
It comprises a plurality of tapered rollers 13c interposed between the inner ring 13a and the outer ring 13b. The lower bearing 14 includes an inner ring 14a fitted to the large-diameter portion 12b of the pinion shaft 12, an outer ring 14b attached to a mounting step of the housing 9, and a plurality of tapered rollers interposed between the inner ring 14a and the outer ring 14b. 14c.

The inner ring 13a of the upper bearing 13 and the carrier 22
The nut 24 has a screw fit 25 in the small diameter portion 12a between
It is attached by. A pressure is applied to the upper bearing 13 by the nut 24 to fix the upper bearing 13 and the lower bearing 14. A pin 26 is inserted into the carrier 22 by knocking. By inserting the pin 26 into a hole 24 a provided in the nut 24, the nut 24 is prevented from loosening.

FIGS. 10 and 11 show a bearing fixing device for preventing a nut 26 screwed into a small diameter portion 12a from being loosened through a lock plate 27. FIG. The lock plate 27 is mounted between the nut 26 and the carrier 22, and a spline 27 a formed on the inner periphery thereof is connected to the spline 23 of the pinion shaft 12. The pin 28 inserted into the nut 26 by knocking is inserted into a hole 27 b provided in the lock plate 27. The nut 26 is loosened by the pin 28 and the lock plate 2
7 prevents it.

[0012]

In the above-described first example of the conventional bearing fixing device, the pin 26 is inserted into the carrier 22 by knocking. However, the dimensional accuracy of the pin 26 and the hole is strict, and the machining is difficult. difficult. Further, since the nut 24 is prevented from being loosened only by the pin 26, during the turning operation, for example, the excavating bucket of the hydraulic shovel hits a rock or the like, and a shocking torque larger than the deceleration output torque is turned from the upper turning body 2. Bearing 1 via wheel 8 and pinion 15
The following inconveniences occur due to the large rotational torque generated by the thrust load applied to the nut 24 from 3. That is, the diameter of the pin 26 is made smaller than the inner diameter of the hole 24a of the nut 24 in consideration of the assemblability. Yes, leading to a reduction in the life of the reduction gear.

In the second example of the conventional bearing fixing device, the dimensional accuracy of the pin 28 and the hole to be inserted into the nut 26 by knocking is strict, and machining is difficult. Further, since the nut 26 is prevented from being loosened by engaging the spline portion 23 of the pinion shaft 12 and the spline portion 27a of the lock plate 27 via the pin 28, the nut 13 is connected to the nut 13 as in the first example. The following inconvenience occurs due to the large rotational torque generated by the applied thrust load. That is, the spline portion 23 and the lock plate 27
Play with the spline portion 27a and the lock plate 2
The play between the hole 27b and the pin 28 causes the spline portion 27a of the lock plate 27 to wear and break. Further, if the spline portion 27a is damaged, the nut 26 is loosened, and the pressure applied to the bearings 13 and 14 is lost, so that the bearing cannot be held. In this example, similarly to the first example, there are also problems such as bending of the pin 28 and breakage.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has as its object to provide a bearing fixing device capable of double-locking a nut for fixing a bearing with a simple structure. I do.

[0015]

According to the present invention, a spline is provided at a tip end of a rotating shaft supported by a bearing, a nut is mounted between a mounting member connected to the spline and the bearing, and the bearing is inserted through the nut. In the bearing fixing device for fixing the nut, a lock plate that meshes with the spline is provided on the upper surface of the nut, the lock plate is fastened to the nut with a bolt, and the nut-side end of the mounting member has a recess for receiving the lock plate. Is provided.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS. In these drawings, the same or corresponding components as those in FIGS. 8 to 11 are denoted by the same reference numerals.

The nut 29 for holding the upper bearing 13 includes:
A screw hole 29a for screwing the bolt 30 is provided.
A spline 31a meshing with the spline 23 is formed at an inner peripheral edge of the lock plate 31, and a bolt hole 31b through which the bolt 30 passes is provided at an intermediate portion. The lock plate 31 has a bolt 3 screwed into the screw hole 29a through the bolt hole 31b on the upper surface of the nut 29.
It is fixed by 0. A recess 22 a for receiving the lock plate 31 is provided at an end of the carrier 22, which is an attachment member, on the nut 29 side.

As described in connection with the conventional bearing fixing device, the spline 23 of the pinion shaft 12 and the spline 31a of the lock plate 31 having small play are generated by a large rotational torque generated by a thrust load applied to the nut 29 from the bearing 13. Causes abnormal wear or cutting, and the spline 23 and the spline 31a
Even if the nut 29 cannot be loosened, the side surface 31c of the lock plate and the side surface 2
2b prevents the nut 29 from being loosened.

FIGS. 4 to 6 show the recess 2 of the carrier 22.
Another embodiment of the present invention in which a chamfered portion 22c for avoiding the bolt 30 is provided on a peripheral wall portion extending from 2a is shown. Other structures are the same as those of the above-described embodiment. In addition,
The plane shape of the lock plate 31 can be arbitrarily selected.

[0020]

According to the present invention, the following effects can be obtained. Since locking of the nut is prevented by the lock plate and bolt, simple processing is required and the cost can be reduced. Since the lock plate is fixed to the nut by the bolt, there is no backlash between the lock plate and the bolt and the nut, so there is no risk of breakage of the bolt. Even if abnormal wear or breakage occurs in the spline portion, which is the meshing portion between the pinion shaft and the lock plate, the lock plate and the concave portion of the carrier are caught, and the nut is held until the applied pressure of the nut to the bearing is lost. Loosening can be prevented. As described above, since the structure for preventing the nut from being loosened is doubled, the occurrence of a breakage of the speed reducer due to the loosening of the nut can be significantly suppressed as compared with the related art. Moreover, the structure is very simple because only the concave portion for accommodating the lock plate is provided in the carrier.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a sectional view showing another embodiment of the present invention.

FIG. 5 is a sectional view taken along line CC of FIG. 4;

FIG. 6 is a sectional view taken along line DD of FIG. 4;

FIG. 7 is a side view illustrating an example of a hydraulic excavator.

FIG. 8 is a cross-sectional side view showing an example of a conventional hydraulic shovel turning device.

FIG. 9 is an enlarged view of a part of FIG. 8 showing an example of a conventional bearing fixing device.

FIG. 10 is a sectional side view showing another example of the conventional bearing fixing device.

FIG. 11 is a sectional view taken along line EE of FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper revolving unit 3 Revolving frame 8 Revolving wheel 9 Housing 10 Ring gear 11 Hydraulic motor 12 Pinion shaft 13 Upper bearing 14 Lower bearing 16 Output shaft G Planetary gear reduction mechanism 22 Carrier 22a Depression 22b Side surface 22c Chamfered portion 23 Spline 29 Nut 29a Screw hole 30 Bolt 31 Lock plate 31a Spline 31b Bolt hole 31c Side surface

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takeshi Kurihara 650, Kandamachi, Tsuchiura-shi, Ibaraki Prefecture Inside the Tsuchiura Plant of Hitachi Construction Machinery Co., Ltd. Tsuchiura factory

Claims (2)

[Claims] 1. A bearing fixing device in which a spline is provided at a tip end of a rotating shaft supported by a bearing, a nut is mounted between a mounting member coupled to the spline and the bearing, and the bearing is fixed via the nut. A lock plate meshing with the spline is provided on an upper surface of the nut, the lock plate is fastened to the nut by a bolt, and a concave portion for receiving the lock plate is provided at an end of the mounting member on the nut side. Bearing fixing device. 2. The bearing fixing device according to claim 1, wherein a chamfered portion for avoiding a bolt is provided on a peripheral wall portion extending from the concave portion of the mounting member.