RU2342548C1 - Inter-rotor support of gas turbine motor - Google Patents

Abstract

FIELD: motors and pumps.

SUBSTANCE: invention relates to gas turbine motors and, particularly to double-rotor gas turbine motor supports, and may be used in aviation engine engineering and other engineering branches where gas turbine motors are used. Inter-rotor support of gas turbine motor includes shaft, high-pressure pivoted rotor, and low-pressure rotor with pivot provided with ports for oil supply, and bearing with external and internal rings. The first ring is fixed to high-pressure rotor pivot. Separator is also included into support. The separator width is bigger than bearing roller width. Low-pressure rotor pivot and shaft are spline coupled with each other creating cavity between them for oil supply. Cavity is connected with pivot openings. Bushing with oil supply ports and internal bearing ring are installed on low-pressure pivot. Bushing is aligned regarding pivot so that it creates cavity coupled with slotted collectors through the ports. Slotted collectors are made at the internal bearing ring ends. Partition is available in cavity and gap is ensured by external ring of bearing is situated with gap with regard fixing element.

EFFECT: improved reliability of motor operation.

1 dwg

Description

The invention relates to gas turbine engines, in particular to the supports of two-rotor gas turbine engines, and can be used in aircraft engine building and other technical fields where gas turbine engines are used.

A well-known inter-rotor support of a gas turbine engine, comprising a high-pressure rotor with a journal and a low-pressure rotor with a journal having openings for supplying oil, and a bearing with inner and outer rings mounted between the rotors, the outer ring of the bearing being fixed in the journal of the high-pressure rotor by means of a locking nuts, and the inner ring of the bearing is fixed on the journal of the low pressure rotor, while the shaft and journal of the low pressure rotor are connected by means of a spline connection to each other with the formation between them of a cavity for supplying oil, connected with the holes of the pin (see RU patent for utility model No. 40652, CL F02C 7/06, publ. September 20, 2004).

A disadvantage of the known bearings is the low reliability of the bearing due to the negative influence of the slots located under the inner ring of the bearing; insufficient lubrication at start-up when the low-pressure rotor does not rotate or rotates weakly, as a result of which the centrifugal force is small, and nozzles located along the axis of the engine do not supply a sufficient amount of oil to the bearing. The outer ring of the bearing is tightened with a fixing nut, and therefore it is not possible to scroll in the trunnion of the high-pressure rotor in case of rollers jamming, which leads to damage (chipping) of the ring treadmill.

The technical result of the proposed invention is to increase the reliability of the engine by ensuring reliable operation of the bearing.

The specified technical result is achieved by the fact that in the inter-rotor support of a gas turbine engine containing a shaft, a high pressure rotor with a pin, a low pressure rotor with a pin having holes for supplying oil, and a bearing with outer and inner rings, the first of which is fixed in the pin of the high rotor pressure, and a separator, while the pin of the low-pressure rotor and the shaft are connected by means of a spline connection to each other with the formation of a cavity for supplying oil between them, in communication with the holes of the pin, according to when a bearing with a separator, the width of which is greater than the width of the bearing roller, is obtained, a sleeve with holes for supplying oil is located on the journal of the low pressure rotor and the inner ring of the bearing is mounted on the sleeve, the sleeve being located relative to the journal with the formation of a cavity communicated through holes in the sleeve with slotted holes collectors formed from the ends of the inner ring of the bearing, while in the cavity a partition is placed, and the outer ring of the bearing is located with a clearance relatively fixed common element.

Bearings with a cage, the width of which is greater than the width of the bearing roller, the so-called bearings with wings or bearings with a widened cage are known (see, for example, patent RU No. 2293193, class F02C 7/06, publ. 10.02.2007).

To ensure guaranteed oil getting into the bearing at start-up and at low speeds, slotted collectors are used (installed). Slotted collectors supply oil radially directly under the “wings” of the bearing cage.

The installation of the inner ring of the bearing on the sleeve with a cavity filled during operation with oil eliminates the harmful effect of the splines on the geometry of the inner ring.

The partition in the cavity between the pin and the sleeve allows you to split the oil flow in the required proportion, for example 2: 1. Those. the amount of oil entering the holes in the sleeve located behind the baffle (in the direction of the oil flow) is two times greater than the amount of oil entering the holes located before the baffle. This is necessary to equalize the temperature on the bearing rings.

The outer ring of the bearing is mounted in the trunnion of the high-pressure rotor with a gap relative to the locking element, which makes it possible to rotate the outer ring in the trunnion of the rotor in case of bearing roller pinching and, as a result, to avoid damage (chipping) of the ring treadmill. The gap can be 0.02 ^{+ 0.01} .

The advantage of the proposed solution lies in the fact that during repair and in case of necessary replacement of the bearing with a bearing with higher overall dimensions, reliable operation of the bearing is achieved without changing the overall dimensions of the rotor elements.

Figure 1 shows a longitudinal section of the inter-rotor bearings;

figure 2 - node I of figure 1 on an enlarged scale.

The inter-rotor support, for example, turbines of an aircraft gas turbine engine, comprises a shaft 1, a bearing 2 with an outer ring 3 and an inner ring 4, and a separator 5 with “wings”. The high pressure rotor is made with a pin 6, and the low pressure rotor is made with a pin 7. The pin 7 of the low pressure rotor is connected to the shaft 1 by means of a spline connection with the formation of a cavity 8 for supplying oil between them. In the pin 7 of the low pressure rotor, the holes 9, 10 for supplying oil connected to the cavity 8 are made. The pin 11 is mounted on the pin 7. The holes 11 are made in the sleeve 11. The sleeve 11 is located relative to the pin 7 of the low pressure rotor to form a cavity 14. B cavity 14 is a partition 15 with a gap δ equal to, for example, δ = 0.03-0.05 mm. The partition 15 divides the cavity 14 into two parts, one of which receives oil from the cavity 8, one row of radial holes 9, and the other part of the cavity along two rows of radial holes 10. The partition 15 prevents the flow of oil from one part of the cavity 14 to another part of the cavity 14, and at the same time in the presence of a gap 5, does not transmit to the seat under the inner ring 4 of the bearing 2 the harmful effect (deformation) from the operation of the splined joint. The partition 15 allows you to distribute the oil through the holes 9 and 10 in the required proportion, for example, 1: 2, i.e. the amount of oil entering the slotted manifold 16 is two times the amount of oil entering the slotted collector 17. The sleeve 11 has a seat in which the inner ring 4 of the bearing 2 is installed. The inner ring 4 is fixed to the sleeve 11 with the sleeve 18. The sleeve 18 is located relative to the left end of the inner ring 4 with the formation of the slotted collector 16. The slotted collector 17 is formed by the ring 19 and the right (first along the oil flow) end of the inner ring 4. The slotted collectors 16 and 17 supply oil under the influence of prices of tractive forces directly under the “wings” of the separator 5. Shaft 1 has holes 20. Oil is pumped through the stationary nozzle 21 into the cavity 22. The outer ring 3 of the bearing 2 is located with a gap δ ₁ , for example, equal to δ ₁ = 0.02 ^{+0, 01} mm relative to the fixing nut 23. The fixing nut 22 fixes the outer ring 3 of the bearing 2 to the high pressure rotor.

The operation of the node is as follows.

At the initial moment, when the engine starts, the high-pressure rotor begins to rotate, and with it the injection pump, which supplies oil through the stationary nozzle 21 to the cavity 22. At this moment, the pin 6 of the high-pressure rotor with the outer ring 3 of the bearing 2 rotates. Oil from the oil cavity 22 by gravity through holes 20 enters cavity 8. From cavity 8, oil through holes 9 and 10 in a 2: 1 ratio enters cavity 14, from where it passes through holes 12 and 13 and through slotted collectors 17 and 16 under the “wings” of separator 5, lubricating rollers and rotating on uzhnoe ring 3 of the bearing 2. As the promotion of the low-pressure rotor, i.e. when the pin 7 is rotated, the amount of oil entering the bearing increases all the time and reaches a maximum at 30% of maximum speed, while maintaining the necessary proportion of oil supply to the right (first along the oil flow) and left ends of the bearing 2.

Claims (1)

An inter-rotor support for a gas turbine engine, comprising a shaft, a high-pressure rotor with a pin, a low-pressure rotor with a pin having holes for supplying oil, and a bearing with outer and inner rings, the first of which is fixed in the pin of the high-pressure rotor, and a cage, while the pin the low pressure rotor and the shaft are connected using a spline connection with each other with the formation between them of a cavity for supplying oil, connected with the holes of the journal, characterized in that when performing the bearing with a cage which is larger than the width of the bearing roller, on the journal of the low pressure rotor there is a sleeve with holes for supplying oil and the inner ring of the bearing is mounted on the sleeve, the sleeve being located relative to the journal with the formation of a cavity communicated through holes in the sleeve with slotted collectors formed from the ends of the inner ring bearing, while in the cavity a partition is placed, and the outer ring of the bearing is located with a gap relative to the locking element.