CN115853689A - Turbine assembly and turbine starter - Google Patents

Abstract

A turbine assembly and a turbine type starting device are used for improving the condition of deformation and damage of a key groove of a turbine rotor, the turbine assembly comprises a ring piece, the turbine rotor and a turbine shaft, and the ring piece is provided with a spline on the axial end face; the turbine rotor is provided with a spline groove on an axial end face, the turbine shaft penetrates through the turbine rotor and the ring piece, the ring piece is fixedly connected with the circumferential direction of the turbine shaft in a circumferential direction, and a spline of the ring piece is inserted into the spline groove of the turbine rotor.

Description

Turbine assembly and turbine starter

Technical Field

The invention relates to a diesel engine starting device, in particular to a turbine assembly and a turbine type starting device.

Background

The starting device is an indispensable part in the starting process of the diesel engine and assists the diesel engine to realize the conversion from static motion state to dynamic motion state. The turbine is used as an important component of the starting device, is a power source of the starting device, is responsible for converting kinetic energy and potential energy in compressed air into mechanical energy of the starting device, and the pneumatic performance and reliability of the starting device are directly influenced by the design of a turbine type line and the arrangement of a shaft system.

The split type rotor-turbine shaft structure is formed by separately processing a turbine rotor and a turbine shaft and connecting the turbine rotor and the turbine shaft through a flat key. The turbine rotor bears big circumferential load at the keyway, and turbine rotor rotational speed is high, and the centrifugal force that arouses is big, and the keyway bears big radial load again, and the turbine rotor is the aluminium material that intensity is low, and the keyway of turbine rotor warp and destroys, all produces very big challenge to product reliability and security.

Disclosure of Invention

The invention aims to provide a turbine assembly and a turbine type starting device, which are used for improving the deformation and damage of a key groove of a turbine rotor.

In a first aspect, the present invention provides a turbine assembly comprising, according to an embodiment of the invention, a ring, a turbine rotor and a turbine shaft; the axial end face of the ring piece is provided with a spline; the axial end face of the turbine rotor is provided with a spline groove; a turbine shaft passing through the turbine rotor and the ring; the ring piece is circumferentially and fixedly connected with the turbine shaft; and the spline of the ring piece is inserted into the spline groove of the turbine rotor.

In one or more embodiments, the ring is connected to the turbine shaft by a flat key.

In one or more embodiments, the material of the flat key and the ring is steel.

In one or more embodiments, the turbine rotor includes an axially projecting hub, and the spline groove is located on an axial end face of the hub.

In one or more embodiments, the turbine shaft is a unitary structure.

In one or more embodiments, the axial end surfaces of the spline teeth of the spline are convexly curved surfaces on the radially outer side, and the height of the convexly curved surfaces decreases radially outward;

the axial end face of the groove part of the spline groove is a convex cambered surface at the radial outer side, and the depth of the convex cambered surface is reduced along the radial outer direction;

the key teeth are inserted into the groove parts, and the convex arc surfaces of the key teeth are attached to the convex arc surfaces of the groove parts.

In one or more embodiments, the axial end surface of the key tooth is provided radially inside with a projection that projects from the axial end surface of the key tooth;

a recess is formed in the radial inner side of the axial end face of the groove, and the recess is recessed from the axial end face of the groove;

the protruding part is inserted into the concave part.

In one or more embodiments, the flanks of the spline teeth of the spline are planar surfaces perpendicular to the circumferential direction;

the side surface of the groove part of the spline groove is a plane vertical to the circumferential direction;

the key teeth are inserted into the groove parts, and the side surfaces of the key teeth are attached to the side surfaces of the groove parts.

In one or more embodiments, the edges of the spline teeth of the spline are rounded.

In a second aspect, the present invention provides a turbine starting apparatus, which, according to an embodiment of the present invention, comprises the above-mentioned turbine assembly.

The embodiment of the invention has at least the following beneficial effects:

1. the ring piece is used for transmitting the rotation of the turbine shaft to the turbine rotor, the number of the key teeth of the spline of the ring piece is large, the load of the turbine rotor is equally divided, the stress borne by the spline groove is reduced, and the turbine rotor is protected from being damaged.

2. The ring piece is located at the axial side of the turbine rotor, so that the spline groove of the turbine rotor deviates from the root of the axial center of the turbine rotor, the region with the largest radial load is avoided, the stress borne by the spline groove is reduced, and the turbine rotor is protected from being damaged.

Drawings

The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and examples, in which:

FIG. 1 is a cross-sectional view of a turbine assembly;

FIG. 2 is an oblique view of the ring;

FIG. 3 is an oblique view of a turbine rotor;

FIG. 4 is a cross-sectional view of a turbine starter assembly;

reference numerals:

1-a turbine assembly;

2-a ring member;

3-a turbine rotor;

4-a turbine shaft;

5-a duct of the turbine rotor;

6-a pore canal of a ring piece;

7-axial end face of ring member;

8-splines;

9-spline teeth;

10-axial end face of the turbine rotor;

11-spline grooves;

12-a trough portion;

13-axial end faces of the key teeth;

14-convex arc surface of key tooth;

15-axial end faces of the groove portions;

16-convex arc of groove;

17-projections of the spline teeth;

18-a recess of a groove portion;

19-flanks of the spline teeth;

20-the sides of the trough;

21-a flat bond;

a keyway of a 22-turbine shaft;

23-keyway of ring;

24-a hub portion;

25-root of the turbine rotor;

26-turbine type starting device;

27-turbine vanes;

28-an exhaust side bearing;

29-mid-stage bearings;

30-an output side bearing;

31-shaft seal;

32-baffle ring;

33-a gasket;

34-a nut;

35-a protective collar;

36-an exhaust enclosure;

37-turbine shell.

Detailed Description

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

It is noted that these and other figures which follow are merely exemplary and not drawn to scale and should not be considered as limiting the scope of the invention as it is actually claimed.

Fig. 1 shows a cross-sectional structure of a turbine assembly 1 in axial section. Fig. 2 shows the ring member 2 in an oblique view. Fig. 3 shows a perspective view of the turbine rotor 3. As shown in fig. 1, the turbine assembly 1 includes a ring 2, a turbine rotor 3, and a turbine shaft 4. With further reference to fig. 3, the turbine rotor 3 has a bore 5 in the center, the bore 5 having an inner diameter substantially equal to the outer diameter of the turbine shaft 4, the turbine shaft 4 passing through the bore 5 of the turbine rotor 3, the turbine rotor 3 fitting radially outside the turbine shaft 4. With further reference to fig. 2, the ring 2 has a hole 6 in the center, the inner diameter of the hole 6 is substantially the same as the outer diameter of the turbine shaft 4, the turbine shaft 4 passes through the hole 6 of the ring 2, the ring 2 is sleeved on the outer side of the turbine shaft 4 in the radial direction and is tightly connected with the turbine shaft 4 in the circumferential direction, the ring 2 and the turbine shaft 4 do not rotate relative to each other in the circumferential direction, and details of the tight connection between the ring 2 and the turbine shaft 4 in the circumferential direction will be described later.

With continued reference to fig. 2, the ring member 2 is provided with a spline 8 on the axial end surface 7, the spline 8 includes a plurality of key teeth 9, the key teeth 9 protrude from the axial end surface 7, and the plurality of key teeth 9 are circumferentially and uniformly distributed on the axial end surface 7. In the illustrated embodiment, the spline 8 illustratively includes six splines 9, the splines 9 projecting axially from the axial end face 7 and extending radially on the axial end face 7.

With continued reference to fig. 3, the turbine rotor 3 is provided with a spline groove 11 at the axial end face 10, the spline groove 11 including a plurality of groove portions 12, the groove portions 12 being recessed from the axial end face 10, the plurality of groove portions 12 being circumferentially evenly distributed on the axial end face 10. In the illustrated embodiment, the spline grooves 11 illustratively include six groove portions 12, the groove portions 12 being axially recessed from the axial end face 10 and extending radially on the axial end face 10.

With continued reference to fig. 1, the spline 8 of the ring 2 is inserted into the spline groove 11 of the turbine rotor 3, each spline tooth 9 of the spline 8 is inserted into each groove 12 of the spline groove 11, the rotation of the turbine shaft 4 is transmitted to the turbine rotor 3 through the ring 2, the number of the spline teeth 9 of the spline 8 is large, the load of the turbine rotor 3 is equally divided, the stress borne by the groove 12 of the spline groove 11 is reduced, and the turbine rotor 3 is protected from being damaged. In addition, the ring member 2 is located on the axial side of the turbine rotor 3, the spline grooves 11 of the turbine rotor 3 deviate from the root of the axial center of the turbine rotor 3, the area with the largest radial load is avoided, the stress borne by the spline grooves 11 is reduced, and the turbine rotor 3 is protected from being damaged. Further, the area over which the spline teeth 9 of the spline 8 apply force to the groove portions 12 of the spline grooves 11 is large, and stress applied to the groove portions 12 of the spline grooves 11 is reduced, thereby protecting the turbine rotor 3 from damage.

With continued reference to fig. 2, the axial end surface 13 of the key tooth 9 is a convexly curved surface 14 on the radially outer side, and radially outward, the height of the convexly curved surface 14 decreases, and the height of the convexly curved surface 14 is the axial distance between the convexly curved surface 14 and the axial end surface 7 of the ring member 2, that is, the height of the key tooth 9. In the illustrated embodiment, the convexly curved surfaces 14 extend radially from approximately the middle of the radial direction of the key teeth 9 to the radially outermost ends of the key teeth 9 and meet the axial end surface 7 of the ring member 2.

With continued reference to fig. 3, the axial end face 15 of the groove portion 12 of the spline groove 11 is a convex arc face 16 on the radially outer side, and radially outward, the depth of the convex arc face 16 decreases, and the depth of the convex arc face 16 is the axial distance between the convex arc face 16 and the axial end face 10 of the turbine rotor 3, that is, the depth of the groove portion 12. In the illustrated embodiment, the convex arc surface 16 extends radially from substantially the middle in the radial direction of the groove portion 12 to the radially outermost end of the groove portion 12, and meets the axial end surface 10 of the turbine rotor 3.

With continued reference to fig. 1, the key teeth 9 are inserted into the groove portions 12, the groove portions 12 are mainly forced by the radially outer portions, the engagement of the key teeth 9 and the groove portions 12 on the radially outer sides is realized by the attachment of the convex arc surfaces 14 and the convex arc surfaces 16, the shape changes of the convex arc surfaces 14 and the convex arc surfaces 16 are continuous and moderate, local stress concentration is avoided when the key teeth 9 apply force to the groove portions 12, the stress borne by the groove portions 12 is reduced, and the turbine rotor 3 is protected from damage.

With continued reference to fig. 1, since the shape change is continuous and gradual, the limiting action of the convex arc surface 16 on the convex arc surface 14 is poor, the convex arc surface 14 is easy to slip relative to the convex arc surface 16, so that the insertion groove portion 12 of the key tooth 9 is not in place, and the insertion of the ring member 2 into the turbine rotor 3 is not in place, for example, in fig. 1, the ring member 2 rotates counterclockwise, the axis of the ring member 2 does not coincide with the axis of the turbine rotor 3, but deflects counterclockwise by a certain angle, the convex arc surface 14 of the key tooth 9 does not abut against the convex arc surface 16 of the groove portion 12, but has a certain gap, and the insertion groove portion 12 of the key tooth 9 is not in place.

With continued reference to fig. 2, the axial end surfaces 13 of the key teeth 9 are provided with projections 17 on the radially inner side, the projections 17 projecting from the axial end surfaces 13 of the key teeth 9. In the illustrated embodiment, the projection 17 projects axially from the axial end face 13 of the spline 9, and the projection 17 is a part of the annular ring in the circumferential direction, and extends radially from approximately one third of the radial direction of the spline 9 to the radially innermost end of the spline 9, and the radially inner wall surface thereof becomes a part of the inner wall surface of the port 6.

With continued reference to fig. 3, the axial end surface 15 of the groove portion 12 is provided with a recess 18 radially inward, the recess 18 being recessed from the axial end surface 13 of the groove portion 12. In the illustrated embodiment, the recess 18 is recessed in the axial direction from the axial end surface 15 of the groove portion 12, the recess 18 extends radially from approximately one third of the radial direction of the groove portion 12 to the radially innermost end of the groove portion 12, communicating with the port passage 5, and the recess 18 of each groove portion 12 of the spline grooves 11 circumferentially meet in a complete annular shape.

With continued reference to fig. 1, the key teeth 9 are inserted into the groove portion 12, the protrusion 17 is inserted into the recess 18, and a wall surface on a radial outer side of the protrusion 17 is attached to a wall surface on a radial outer side of the recess 18 to form a positioning limit, so that the key teeth 9 are accurately inserted into the groove portion 12, the convex arc surfaces 14 of the key teeth 9 are ensured to be attached to the convex arc surfaces 16 of the groove portion 12, and then the ring member 2 is ensured to be accurately inserted into the turbine rotor 3.

With continued reference to FIG. 2, the flanks 19 of the key teeth 9 are planar and perpendicular to the circumferential direction. With continued reference to fig. 3, the side surfaces 20 of the groove 12 are planar and perpendicular to the circumferential direction. The spline teeth 9 are inserted into the groove 12, the side surfaces 19 of the spline teeth 9 are attached to the side surfaces 20 of the groove 12, and the force applied by the spline teeth 9 to the groove 12 is tangential to the circumferential direction, has no radial and axial components, and applies only a rotational force to the turbine rotor 3, and does not apply a radial force and an axial force to the turbine rotor 3.

With continued reference to fig. 2, the edges of the spline teeth 9 are rounded and relaxed in shape and not sharp, so that local stress concentration is avoided when the spline teeth 9 apply force to the groove portions 12, and stress received by the groove portions 12 is reduced, thereby protecting the turbine rotor 3 from damage.

With continued reference to fig. 1, the ring 2 is connected to the turbine shaft 4 by a flat key 21. In the illustrated embodiment, the ring 2 is connected to the turbine shaft 4 by two flat keys 21 arranged facing away from each other, and correspondingly the turbine shaft 4 is provided with two key slots 22 facing away from each other, and further with reference to fig. 2, correspondingly the ring 2 is provided with two key slots 23 facing each other, and the two key slots 23 occupy part of the projections 17 of the two key teeth 9. In another embodiment, the ring 2 is connected to the turbine shaft 4 by other means, for example, the bore 6 of the ring 2 is provided with internal splines, the outer circumferential surface of the turbine shaft 4 is provided with external splines, and the ring 2 is splined to the turbine shaft 4.

With continued reference to fig. 1, the flat key 21 and the ring member 2 are made of steel, so that the strength of the flat key 21 is close to that of the ring member 2, the strength of the flat key 21 is higher than that of the ring member 2, and the flat key 2 does not damage the key groove 22 when applying force to the key groove. The material of the flat key 21 and the ring 2 is exemplarily 45# steel. The material of the turbine rotor 3 is illustratively an aluminum alloy. The material of the turbine shaft 4 is illustratively 20CrMnTi.

The split type turbine shaft comprises a plurality of shaft sections in the axial direction, the shaft sections are connected through a connecting structure (such as a thread structure), when large torque is applied, the connecting structure between the shaft sections is easy to damage, and the torque output capacity of the turbine type starting device is limited to a great extent.

With continued reference to fig. 1, the turbine shaft 4 is a unitary structure, continuous in the axial direction, also referred to as a unitary turbine shaft, that avoids axial connection of multiple shaft segments in a split turbine shaft, provides a greater torque output capability than a split turbine shaft, and is capable of outputting a large torque.

With continued reference to fig. 3, the turbine rotor 3 is provided with a hub 24, the hub 24 protrudes axially, the axial end face 10 of the hub 24 is also the axial end face 10 of the turbine rotor 3, the axial protrusion of the hub 24 further deviates the axial end face 10 from the axial central position of the turbine rotor 3, the spline groove 11 is located on the axial end face 10 of the hub 24, further deviates the axial central position of the turbine rotor 3, and further deviates the axial central root 25 of the turbine rotor 3, so as to reduce the weakening of the strength of the root 25 of the turbine rotor 3, ensure the ability of the root 25 of the turbine rotor 3 to bear centrifugal force, protect the root 25 of the turbine rotor 3 from being damaged under high centrifugal force at high rotation speed, and be capable of bearing high rotation speed. In addition, the radial outer side of the hub 24 has no solid structure, so that the centrifugal force generated during rotation is small, the radial load is small, the stress borne by the spline grooves 11 is reduced, the spline grooves 11 are protected from being damaged at a high rotating speed, and the high rotating speed can be borne.

Fig. 4 shows a sectional structure of the turbine starter 26 in an axial section. As shown in fig. 4, the turbo starting apparatus 26 includes the above-described turbine assembly 1.

In the embodiment shown in fig. 4, the turbine starting device 26 further includes, for example, a turbine vane 27, a retainer 32, a gasket 33, a nut 34, a protective retainer 35, an exhaust casing 36, and a turbine casing 37. The turbine type starting device 26 adopts a single-stage axial flow impulse turbine and comprises a turbine guide vane 27 and a turbine rotor 3, the turbine type starting device 26 is fed with air from the middle, and the turbine guide vane 27 is fixed on the end surface of a turbine shell 37 through three screws. Besides being axially limited by the turbine rotor 3, the ring member 2 is also axially limited by the exhaust side bearing 28, the gasket 33 and the nut 34 on one axial side, so that the ring member 2 is axially fixed.

With continued reference to fig. 4, the turbo starter 26 further includes an exhaust-side bearing 28 and an intermediate-stage bearing 29, the exhaust-side bearing 28 being located axially on the exhaust side of the turbine rotor 3 and near the turbine rotor 3 and supporting an axial end portion of the turbine shaft 4, the intermediate-stage bearing 29 being located axially on the output side of the turbine rotor 3 and near the turbine rotor 3 and supporting an axial middle portion of the turbine shaft 4, the exhaust-side bearing 28 and the intermediate-stage bearing 29 supporting the turbine shaft 4 on both axial sides near the turbine rotor 3, the support rigidity for the portion of the turbine shaft 4 axially between the exhaust-side bearing 28 and the intermediate-stage bearing 29 being good, and the stability of the turbine rotor 3 during operation being improved. Illustratively, the exhaust side bearing 28 is a high speed bearing and is sealed, bearing lubricated by grease, interference fit with the turbine shaft 4, located in a bore of the exhaust housing 36 and clearance fit with the bore of the exhaust housing 36, and the mid-stage bearing 29 is a high speed bearing and is sealed, bearing lubricated by grease, interference fit with the turbine shaft 4, located in a bore of the turbine vane 27 and clearance fit with the bore of the turbine vane 27.

With continued reference to fig. 4, the turbine starter assembly 26 further includes an output-side bearing 30, the output-side bearing 30 being located axially on the output side of the turbine rotor 3 and away from the turbine rotor 3, supporting the turbine shaft 4 near the axial ends, a planetary reduction system (not shown) connected to the output side of the turbine starter assembly 26, and a transition region of the turbine rotor 3 in the axial direction, further enhancing the support of the turbine shaft 4 and preventing the turbine shaft 4 from becoming eccentric due to high loads. Illustratively, the output side bearing 30 is a high speed bearing and is open, bearing lubricated by lubricating oil, interference fit with the turbine shaft 4, located within a bore of the turbine housing 37 and clearance fit with the bore of the turbine housing 37.

With continued reference to fig. 4, the turbine starter 26 further includes a shaft seal 31, the shaft seal 31 being located axially on the output side of the mid-stage bearing 29 and radially between the turbine shaft 4 and the turbine vane 27 to isolate oil and gas and complete the shaft seal, the shaft seal 31 being illustratively a lip seal.

Although the present invention has been described with reference to the above embodiments, it is not intended to limit the present invention, and those skilled in the art may make variations and modifications without departing from the spirit and scope of the present invention.

Claims (10)

1. A turbine assembly, comprising:

a ring member having a spline on an axial end surface thereof;

the turbine rotor is provided with a spline groove on the axial end face; and

a turbine shaft passing through the turbine rotor and the ring;

wherein the content of the first and second substances,

the ring piece is fixedly connected with the circumferential direction of the turbine shaft in a circumferential manner;

and the spline of the ring piece is inserted into the spline groove of the turbine rotor.

2. The turbine assembly of claim 1, wherein:

the ring piece is connected with the turbine shaft through a flat key.

3. The turbine assembly of claim 2, wherein:

the flat key and the ring piece are made of steel.

4. The turbine assembly of claim 1, wherein:

the turbine rotor comprises an axially protruding hub, and the spline groove is located on an axial end face of the hub.

5. The turbine assembly of claim 1, wherein:

the turbine shaft is of an integral structure.

6. The turbine assembly of claim 1, wherein:

the axial end face of the key tooth of the spline is a convex cambered surface at the radial outer side, and the height of the convex cambered surface is reduced along the radial outer direction;

the axial end face of the groove part of the spline groove is a convex cambered surface at the radial outer side, and the depth of the convex cambered surface is reduced along the radial outer direction;

the key teeth are inserted into the groove parts, and the convex arc surfaces of the key teeth are attached to the convex arc surfaces of the groove parts.

7. The turbine assembly of claim 6 wherein:

the axial end surface of the key tooth is provided with a protruding part at the radial inner side, and the protruding part protrudes from the axial end surface of the key tooth;

a recess is formed in the radial inner side of the axial end face of the groove, and the recess is recessed from the axial end face of the groove;

the protruding part is inserted into the concave part.

8. The turbine assembly of claim 1, wherein:

the side surface of the spline tooth of the spline is a plane vertical to the circumferential direction;

the side surface of the groove part of the spline groove is a plane vertical to the circumferential direction;

the key teeth are inserted into the groove parts, and the side surfaces of the key teeth are attached to the side surfaces of the groove parts.

9. The turbine assembly of claim 1, wherein:

the edges of the spline teeth of the spline are rounded.

10. A turbine type starting apparatus characterized by comprising:

a turbine assembly according to any one of claims 1 to 9.

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