JPS5958227A - Static-pressure thrust bearing device - Google Patents

Abstract

PURPOSE:To relax the accuracy of parts by adopting a static-pressure thrust bearing system only for the principal thrust direction. CONSTITUTION:When thrust load works upon a central shaft 6 in the left direction indicated by an arrow to displace the central shaft 6, a distance piece 4 and a disc 5 in the left direction, an opening between a pressure supply port 1a and an oil supply groove 5a is enlarged, and resistance to supplied pressure is lowered. As resistance between a partition plate 3 and the distance piece 4 is constant, pressure on anti-thrust side is increased by oil flowing through an opening between a pressure supply port 1a and an oil supply groove 5a, an oil path 5b, an oil discharge groove 3a and an oil discharge port 3b. Thrust load capacity is effective only for thrust load in the left direction indicated by an arrow.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydrostatic thrust bearing device that receives a thrust load applied to a shaft.

The present inventors developed an improved hydrostatic thrust bearing device in the 1970s.
It has already been proposed as No. 7-90327. This device is the first
As shown in the figure, the 1 m long rollers supporting both ends of the central shaft 6 are the p-bearing 7, and this pair of rollers is the elastic member 8 for applying preload in the axial direction to the bearing 7, and the pressure supply port).
Annular oil supply 5 is provided on both sides of the outer peripheral portion facing 1a.
sa150 is provided, oil passages 5b and 5a communicating with these oil supply m5a and 5C, respectively, intersect and are opened on both sides, and a required number of discs 5 fixed to the central shaft 6 and a A distance piece 4 inserted on both sides and fixed to the central shaft 6, and a distance piece 4 inserted on both sides and a distance piece 4 are inserted on both sides and fixed to the central shaft 6.

In order to maintain a required gap between the outer circumferential surface of these distance pieces 4 and the side surface of the disk 5, the outer circumferential surface of the distance piece 4 is arranged concentrically with the outer circumferential surface of the distance piece 4. A diaphragm 3 having a concession-shaped oil drain groove 3a on the inner circumferential surface facing the center portion and having this oil drain (oil drain bow communicating with lj3a) 31), and a casing that encloses each of the above-mentioned parts. 1.2, the casing 1 enclosing the disk 5 is provided with a pressure supply bow (1a), and is functionally capable of bearing thrust loads in both directions, and automatically returns to the neutral position when unloading. However, in the case of a multi-stage structure, in order to ensure the cumulative positional accuracy of the bow) 1a and the oil supply grooves 5a and 5c, it is necessary to The accuracy of the width, the relative positional accuracy of the oil supply from both ends of the boat 1a (the oscillation is the accuracy), and the dimensional accuracy of the width of the boat 1a or the interval between the oil supply grooves 5a, 5a, as measured by the gauge. This poses an economical problem.

In normal machines, it is not often that the same level of thrust force is generated in both directions. Also, it is rare that other types of thrust loads can be used in both directions.

Therefore, the present invention uses a static pressure thrust bearing system only in the king thrust direction (the direction in which the center 11111I6 is pushed) to reduce the precision of parts, and one embodiment thereof will be described below with reference to the drawings.

FIG. 2 shows a top view of an embodiment of the present invention, and 7 is a 1 m long rolling bearing, for example, an angular contact, for supporting both ends of the central shaft 6 on the inner peripheral surface of the casing 2 via a sleeve 10. Bearing 8 is the angular contact bearing 7 on the opposite open end side of the central shaft 6 (left side in Fig. 2)
This is an elastic member such as a disc spring for applying preload in the axial direction toward the open end (right end in FIG. 2) of the center 114116. Reference numeral 12 denotes a positioning stopper (spacer) provided between the right angular contact bearing 7 and the end plate 9a in opposition to the elastic member 8.

9 ' t 9 b ij Close both ends of casing 2 1
It is an end plate.

5 is a pressure supply boat) 11L is located at the center on the open end side of the central axis 6 of the pressure supply boat 1a on the outer circumference facing the pressure supply boat 11L.
The concessional oil supply m5 is closed so that the pressure supply bow) 1a is closed at the position regulated by the positioning stopper 12.
An oil passage 5b communicating with the oil supply groove 5a is provided with a required number of discs, for example, two discs, which are opened on the side opposite to the open end of the central shaft 6. These discs 5 are located at the center I! Ii] 6, the pressure supply boat 1a'! i-* is supported on the inner peripheral surface of the casing 1.

Distance pieces 4 are inserted on both sides of these discs 5 and fixed to the central shaft 6. 3 is a partition plate arranged concentrically on the outer peripheral surface of the distance piece 4 in order to maintain a required gap between the outer peripheral surface of the distance piece 4 and the side surface of the disc 5. The distance piece 4 has a concession-shaped oil drain groove 3a on the inner circumferential surface opposite to the central portion of the outer circumferential surface, and has an oil drain boat 3b6 communicating with this drain oil FJ*35L, and the casings 1 and 1 .1 and 2.

In addition, in the present invention, the angular contact bearing 7
Instead, deep groove ball bearings, tapered roller bearings, etc. may be used.

Since the embodiment of the present invention has the above-described configuration, the relative positional relationship between the pressure supply boat 11L and the oil supply groove 5a is such that the supply pressure P8 of the pressure supply boat 1a is closed or lowered from the pressure supply boat 1a as shown in the third figure. The oil flows through the oil supply groove 5a and the oil passage 5b into the gap between the left side partition plate 3 and through the oil supply 45a into the gap between the right side partition plate 3. In this case, disk 5
No axial force acts on .

A thrust load acts on the center shaft 6 in the left direction as shown by the arrow in FIG. 4, and the resistance of the elastic member 8 is overcome and the center shaft 6, distance piece 4, disk 5, etc. 11)
If the gap between L and the oil supply groove 5a is opened, or the degree of opening between the pressure supply bow 1a and the oil supply groove 5a which was previously open is large, the resistance to the supply pressure will decrease, and the Since the resistance between the distance piece 4 is constant, the opening degree between the pressure supply port 1a and the oil supply groove 5a, and the oil passage 5bv
The pressure on the anti-thrust side (the pressure in the right direction indicated by the arrow in FIG. 4) generated by the oil flowing through the drain oil 043a and the drain oil bow 31) increases.

Therefore, as the thrust load increases, the pressure opposing it also increases, allowing the thrust load to be received. Thrust load and pressure supply bow) 11L opening, i.e. center axis 6
There is a relative relationship between the displacement of the center shaft 6 and the thrust load.In order to reduce the displacement of the central shaft 6 against the thrust load (increase bearing rigidity), 1) increase the supply pressure. ■Increase the area of pressure supply boat IIL or increase the number of boats. (2) This can be achieved by reducing the gap between the partition plate 3 and the distance piece 4.

However, since there is a gap between the 0T moving parts (disc 5, distance piece 4, center shaft 6, etc.) and fixed parts (diaphragm 3, casing 1.2, etc.) that can absorb the precision of the parts, the bearing The stiffness can be compensated for by increasing the supply pressure or by increasing the number of pressure supply boats IB- or by increasing the area by changing the shape of the boats 1&.

Further, the thrust load capacity of the device of the present invention is effective only for the thrust ljt to the left as indicated by the arrow in FIG. By increasing the number of distance pieces 4 and partition plates 3 to form a multi-stage configuration, the number increases proportionally.

As can be understood from the above explanation, according to the present invention, a pair of rollers fully supported at both ends of the center shaft 6 are connected to the bearing 7 and have an elastic force that applies preload in the axial direction toward the open end of the center shaft 6. A member 8, a positioning stopper 12 opposing the member 8, and a positioning stopper 12 with the central shaft 6 located on the open end side of the central shaft 6 of the pressure supply boat la on the outer peripheral portion facing the pressure supply boat 1a.
Pressure supply bow in the position regulated by 2) 1a
A concession-shaped oil supply groove 5-a is provided so as to close the oil supply groove 5-a, and an oil passage 5b communicating with this oil supply groove 5a is opened on the side opposite to the open end of the central shaft 6. A disk 5 of
The distance pieces 4 are inserted on both sides of the disc 5 and fixed to the center @ 6, and the distance pieces 4 are inserted in order to maintain a required clearance between the outer circumferential surface of these distance pieces 4 and the side surface of the disc 5. A concession-shaped oil drain groove 3a is provided concentrically on the outer circumferential surface of the distance piece 4, and is provided on the inner circumferential surface portion facing the center of the outer circumferential surface of the distance piece 4.
31) Required number of partition plates 3 having t-
Since the casing 1゜2 that encloses each of the above-mentioned parts and the casing 1 that encloses the disk 5 are provided with a pressure supply boat 1a, ■ the casing 1, the partition plate 3, the distance piece 4 and If the width (length in the axial direction) of each disc 5 is made uniform and a fitting part is provided, there will be a sufficient gap in the axial direction, and errors in assembly will not become a functional obstacle. Therefore, it is possible to easily combine a plurality of stages within the range permitted by structural rigidity, and it is possible to cope with an increase in load capacity and to equalize load sharing. ■
Since it is possible to equalize the load distribution, the overall durability can be increased, and even in the event of a partial accident, that part (disc 5
, distance piece 4, partition plate 3, etc.). ■By providing a gap between the movable part and the fixed part that is large enough to absorb the part precision, the part precision can be reduced.
Furthermore, since an oil film is formed in this gap to avoid metal contact, it is possible to increase the speed and extend the service life. ■ Bearing stiffness can be compensated by increasing the supply pressure or the number of pressure supply boats. ■A pair of rollers with preload applied to an elastic member supports the middle IQ shaft in the casing using bearings, so it can withstand external loads during assembly and startup. ■Especially in this invention, each part is 1t3t4t
5 width and pressure supply port) 11L from the right side end (the end on the open end side of the center shaft 6).The parts accuracy can be reduced to WR only by the relative position accuracy of the oil supply J5' from the right end (the end on the open end side of the central shaft 6), and it can be provided at a low price. play.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the device already proposed, FIG. 2 is a sectional view of an embodiment of the present invention, and FIGS. 3 and 4 are sectional views for explaining the operation of the main parts thereof. 1.2...Casing, 1a...
・・・・・・Pressure supply boat, 3・・・・・・・・・Diameter,
3a・・・・・・Excludes mountain bird, 3b・・・・・・
・・Oil drain boat, 4・・・・・・・Distance piece, 5・・・・・・Disc, 5a・・・・・・・
...Oil supply groove, 5b...Oil passage, 6...
... Central shaft, 7 ... Angular contact bearing, 8 ...... Elastic member,
ga, gb・・・・・・End plate, 10・
Old... use! J-7", 12...Positioning stopper.

Claims (1)

[Claims] A pair of roller bearings supporting both ends of the center shaft, an elastic member that applies preload in the axial direction toward the open end of the center shaft, a positioning stopper that opposes this, and an outer peripheral portion that faces the pressure supply boat. An annular oil supply groove is provided on the open end side of the central shaft of the pressure supply boat so as to close the pressure supply boat at a position where the central shaft is regulated by the positioning stopper, and an oil passage communicating with the oil supply groove is provided. A required number of discs opened on the opposite open end side of the central shaft and fixed to the central shaft, distance pieces inserted on both sides of the discs and fixed to the central shaft, and outer peripheral surfaces of these distance pieces. An annular oil drain groove is arranged concentrically on the outer peripheral surface of the distance piece in order to maintain a required clearance between the distance piece and the side surface of the disc, and an annular oil drain groove is provided on the inner peripheral surface portion opposite to the central portion of the outer peripheral surface of the distance piece. , a required number of bulkheads each having an oil drain boat communicating with the oil drain groove, a casing enclosing each of the above-mentioned parts, and a pressure supply boat provided in the casing enclosing the disk. Thrust bearing device.