JPS58180830A - Dynamic pressure type thrustward hydraulic bearing device - Google Patents

Abstract

PURPOSE:To improve wear resisting performance of a bearing against contact of a bearing part at the time of either a suspension or a low speed revolution, by processing a group of parts having smaller diameters than that of an osculating circle between the edge face and a thrust bearing on the thrust bearing. CONSTITUTION:A thrust bearing 12 is fixed to a housing 11 in opposition to a lower end face of a shaft 13. The upper surface of the thrust bearing 12 is processed precisely and a group of parts 12 having smaller diameters than that of an osculating circle between the edge face of the shaft 13 and the thrust bearing 12 is processed. With this constitution, even if surplus force is applied there occurrs little wear as a corner part 13B of the shaft 13 only touches a flat part 12D of the thrust bearing 12 and does not touch boundary lines 12B and 12C of the group 12.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dynamic pressure type thrust direction fluid bearing device, and an object of the present invention is to obtain a device having excellent wear resistance against contact during stoppage or low speed rolling.

? As shown in Figures 1 and 2, the hydrodynamic thrust direction hydrodynamic bearing device (hereinafter referred to as the hydrodynamic bearing device) developed since iE has holes machined with high precision in the housing 1, and the thrust bearing is installed in the lower part of the housing 1. Attach 2 to the + corner of the hole, and...
A shaft 3 is rotatably provided in the hole of the housing 1. On the other hand, the upper surface of the thrust bearing 2 facing this is etched into a group 2 shaped as shown in FIG.
A has been processed and lubricating oil 4 has been applied. When either shaft 3 or housing 1 is rotated by a motor (not shown), pressure is generated by the pumping action of group 2A, and the shaft 3 rotates without contact. .

However, when this type of conventional hydrodynamic bearing device is used in the turntable of a record player,
When the record is changed when the record is stopped, an excessive force (for example, 10 kg) is artificially applied to this hydrodynamic bearing, and as shown in FIG. , 2C may cause the shaft 13 or the dalouve part to wear out, and it may not be possible to obtain sufficient supporting force or Oka+1 property even if the rotation speed is increased to the specified speed.
.

The present invention solves the above-mentioned conventional drawbacks, and one embodiment thereof will be described below with reference to FIGS. 3 to 6.

In FIG. 3, a hole 11A is drilled in the housing 11, and a lower end 13A is precisely finished into a flat surface in the hole 11A.
A shaft 13 on which a radial fluid bearing group 13C113D is provided by etching or the like is rotatably provided 5. Further, a retaining ring 15 is provided below this shaft. A thrust bearing 12 is fixed to the housing still facing the lower end surface of the shaft 13. As shown in Fig. 4, the thrust bearing 12 has its upper surface machined with high precision by polishing, etc., and a group 12 is machined in the center, and lubricating oil is applied to three groups along with radical groups 13C and 13D. 14 is lubricated, and a motor (not shown) rotates either the shaft 131 or the housing 11 at a constant speed.
Pressure is generated by 13C and 13D nohomping action,
In this embodiment, the diameter of group 12A is set to be small compared to the shaft diameter even if an excessive force is artificially applied when stopping, as shown in Fig. 6. However, the shaft 130 corner 13
B only contacts the flat part 12D of the l-plane of the thrust bearing 12, and the boundary lines 12B and 12C of the group 12A
Since it does not come into contact with Even after repeated reverse rotation tests, there was almost no wear, and sufficient bearing support force (or rigidity) was obtained at the specified rotation speed.

Note that the group may be provided on the lower end surface 13A of the shaft 13. Note that when the corner 13B of the shaft 13 is rounded, the diameter of the group is determined by the diameter of the thrust bearing 1 of the lower end 13A.
The diameter is designed to be smaller than the diameter of the V-flat part that actually comes into contact with 2. Note that the groove 12E in FIG. 4 is a ventilation hole, and is etched together with the group 12A.

As described above, according to the present invention, it is possible to obtain a fluid bearing in the thrust direction and f' that has excellent wear resistance against contact of the bearing portion during stoppage or low speed rotation.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional hydrodynamic bearing device, Fig. 2 is a shape diagram of the same group, Fig. 3 is a cross-sectional view of a hydrodynamic thrust-direction hydrodynamic bearing device according to an embodiment of the present invention, and Fig. 4 is the same. FIG. 6 is an enlarged sectional view of the main part of FIG. 3. 11... Housing, 11D... Hole, 12
...Thrust bearing, 1'2A...Group, 13...Shaft. Name of agent: Patent attorney Toshio Nakao and 1 other person @1
Figure 12 Figure B Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] A housing, a shaft rotatably provided in a hole provided in the housing, and a planar thrust provided at a position corresponding to an end surface of the shaft with lubricating oil interposed therebetween. A dynamic pressure type thrust direction fluid consisting of a bearing, in which a group having a diameter smaller than the diameter of the end face of the shaft in contact with the thrust bearing is machined on either the end face of the shaft or the thrust bearing. Bearing device.