SU420819A1 - SLIDE BEARING - Google Patents

Description

one

The invention relates to the field of mechanical engineering and can be used in the machine tool industry for spindle assemblies of precision machine tools. At present, hydrodynamic sliding bearings are used for spindle supports consisting of several self-aligning segments, which, with increasing speed of rotation of the shaft, rotate and change the gap between the shaft and the segments.

Known bearings allow adjustment of the clearance and ensure high accuracy of the spindle assembly.

However, as established by laboratory and industrial tests, when the load changes along the length of the bearing or the spindle deflection, additional stresses arise at the ends of the bearing assembly. In violation of the gap between the shaft and the segments, which occurs when the lubricant is contaminated or when heated, there is an increased wear and a related decrease in the accuracy of the mechanism.

In order to achieve high precision of the operation of spindle precision machines, such bearings are needed that would automatically change the clearance in the friction zone depending on the speed of the sliding surfaces within 5 microns.

The described (narrow) sliding bearing has the following advantages over known bearings: a decrease in sensitivity to sticking or abrasive destruction by loose particles; the ability to be pre-loaded at high rigidity, even at zero speed; the ability to adapt to inaccurate manufacturing and installation of the shaft journal; increased damping and improved dynamic characteristics of the bearing assembly.

The described sliding bearing with automatic adjustment of the clearance ensures the automatic maintenance of the required clearance in the friction zone in various operating modes due to the axial displacement of the sleeves relative to each other. By design, the sleeves are designed so that on the inner side surfaces they have a taper that mates with a spring ring cut in one place, and on the outer sides the sleeves are spring-loaded Spring, whose force is limited by nuts. The lubricant is fed through a supply nipple, calibrated bores and a spool, into the cavities above the pistons. The pistons have calibrated bores. The upper and lower cavities are interconnected by channels. In one of the lower cavities there is a threaded hole in which the shank of the corrugated cylinder is wrapped, the other end of the corrugated cylinder is mated with the spool, the movement of the finisher is balanced by a spring.

FIG. 1 image a general view of the nodshinnika with a partial section; in fig. 2 is a section along A-A in FIG. one; in fig. 3 is a section along BB in FIG. one.

The bearing has a housing 1 in which two bronze bushings 2 are installed along a sliding fit with tapered surfaces on the inner ends and with spherical inner surfaces in contact with the spherical 3 shafts of the shaft 4. The sleeves 2 are tucked to the benches 3 with springs 5 and nuts 6. The gap between the spherical surfaces of the sleeves 2 and the rims 3 is adjusted by means of a spring of the split ring 7 with conical surfaces on the ends that are in contact with similar surfaces of the rings and a hydraulic regulator with reverse a bond, consisting of a ring vzai.modeystvuyusch .ih schtokom 7 8 9 E porschn forming radial bores in the casing 1 x two cavities: A lower and upper B reported throttling apertures and with each other. In addition, the lower cavities A are sequentially communicated with each other by channels b, and the upper cavities by channels c.

One of the lower legs, A, communicates with the corrugated cylinder 10 of the feedback sensor, which also includes the spool I and the spring 12. The socket in which the feedback sensor is located is communicated by the openings r with the connector 13 and the calibrated orifices - with one of the cavities B.

The cavities B are externally closed by the plugs 14, and between the latter and the rods 8 there is a lever gap corresponding to the smallest design gap between the straps 3 and the sleeves 2. On the shaft 4 there are recesses 15 for breaking the oil film of the outgoing lubricant, being non-contact seals.

The rings and the sleeves are narrow, which contributes to the improvement of the work of the support, by eliminating the edge pressure.

The device works as follows.

At the initial moment of operation, the lubricant under constant pressure from the hydrostation through the throttle, fitting 13, calibrated orifices g and (, the hole e and the channel flows into the upper cavities B. From cavity B through the throttling holes and lubricant enters the lower cavities A. But so As the pressure difference in the cavity is x / 1 and large, the pistons 9 move, and with the rods push the spring ring 7, which interacts with the sleeves 2 with a conical side surface at an angle p, increasing the gap between the edges 3 of the shaft 4 and the sleeves 2, allowing lubricating In this steady state operation through throttling orifices, the pressure is equalized in cavities A and B, the corrugated cylinder 10 will displace the spool 11 in such a position that the outflow of lubricant from the calibrated the holes d corresponded to the outflow of lubricant from the friction zone between the legs ;; 3 and the sleeves 2. But as soon as the operating mode of the bearing unit changes, or the load on the sub-bearing unit changes, immediately The balance equilibrium is eliminated, and the corrugated cylinder 10 accordingly will not thrust the collar 11, which will open or close the calibrated holes. There will be a change in pressure in the upper cavity B and thus the pressure regulator will work again. Automatic clearance of the gap with feedback occurs, thereby maintaining a constant stable operation of the bearing assembly. The lubricant flows out of the friction zone of the forks 3 and the sleeves 2 extends to the recesses 15 located on the shaft 4. Under the action of centrifugal force, the lubricant is thrown onto the walls of the springs 5 and flows into the bath of the hydrostation, where after filtration and cooling through the pump and the throttle again enters in podshnnik. The twist of the sleeves 2 in the housing 1 is absent, since the sleeves are clamped between the springs 5 and the ring 7. The slip with automatic adjustment of the gap can be performed with sleeves 2 having a spherical interface with sleeves 3 of the shaft 4, and with sleeves 16 having a surface sonor.

Subject invention

Claims (3)

1. Slip-on padding with an adjustable gap between the rubbing surfaces, comprising a housing, inside which there is an insert loosely mounted on the shaft and pressed from the ends with nuts, characterized in that it is equipped with a split spring ring with conical surfaces MI to automatically adjust the clearance an end faceplate and a hydraulic feedback regulator made in the form of rods located in the radial through bores of the rods in the casing with bores contacting the walls of the rods, forming in To each bore there are two cavities, upper and lower, communicated by throttling openings in each other, and channels, the same of which are sequentially communicated with each other and with a feedback sensor, consisting of a corrugated cylinder interacting with each other, communicated with one from the lower cavities, and the spring-loaded spool, to which the oil is pressurized, the liner is made up of two bushings, spring-loaded to the nuts, with spherical internal surfaces that are in contact with spherical ridges formed on the shaft and with conical surfaces on the inner ends, in contact with similar surfaces of split spring rings, interacting with the said shtochka / di, radially screwed into the bores of the threaded plugs with which the housing is provided. 2. A sub-item according to claim 1, characterized in that the mutually contacting surfaces of the sleeves and along the shaft shaft are tapered. 3. Bearing on PP. 1 and 2, characterized in that, for the purpose of sealing, on the shaft on both sides of it, grooves are made, tearing the oil film. niT FIG. S6 9ue, S