Search

CN-115968428-B - System for controlling the pitch of the propeller blades of an aircraft turbine engine

CN115968428BCN 115968428 BCN115968428 BCN 115968428BCN-115968428-B

Abstract

A system (34) for controlling the pitch of a propeller blade (10) of an aircraft turbine engine is disclosed, characterized in that it comprises-a cup (58) having an annular wall (58 a) extending around an axis (A) intended to set the axis for the pitch of the blade, said annular wall (58 a) having a lower axial end enclosed by a bottom wall (58 b) and an open upper axial end configured to enable the mounting of a root (14) of the blade (10) inside the cup (58), and-a retaining ring (152) extending around said axis (A) and configured to be mounted around the root (14), said retaining ring (152) being a double-claw clutch ring comprising two annular rows of outer claw teeth (154, 156) constituting respectively an active claw tooth and a safety claw tooth.

Inventors

  • Clement Cortet
  • Vivian mikar cotier
  • Vincent juden
  • Regis Eugene Henry Severt

Assignees

  • 赛峰飞机发动机公司

Dates

Publication Date
20260505
Application Date
20210715
Priority Date
20200724

Claims (16)

  1. 1. A system (34) for controlling the pitch of a propeller blade (10) of an aircraft turbine engine, characterized in that it comprises: -a cup (58) comprising an annular wall (58 a) extending around an axis (a) intended to set an axis for the pitch of the propeller blade, the annular wall (58 a) comprising a lower axial end enclosed by a bottom wall (58 b) and an open upper axial end configured to enable the root (14) of the propeller blade (10) to be mounted inside the cup (58), the bottom wall (58 b) being configured to cooperate in a form-fitting manner with the free end (28) of the root (14) such that the cup (58) is rotationally fixed to the root (14) around the axis (a), and -A securing ring (152) extending around the axis (a) and configured to be mounted around the root (14), the securing ring (152) being configured to be mounted inside the cup (58) and to cooperate with the root (14) and the annular wall (58 a) of the cup (58), respectively, to ensure an axial retention of the root (14) inside the cup (58), And the stationary ring (152) is a ring with a double-jaw clutch comprising two annular rows of outer jaw teeth (154, 156), a first one of the rows of outer jaw teeth being configured to cooperate with a first inner jaw tooth of the annular wall (58 a) of the cup (58) by a jaw clutch and with these first inner jaw teeth by an axial support (G), the outer jaw teeth of the first row being complementary to the first inner jaw teeth to ensure retention of the root (14) in the cup (58), a second one of the rows of outer jaw teeth being configured to cooperate with a second inner jaw tooth of the annular wall (58 a) of the cup (58) by a jaw clutch and being spaced apart from these second inner jaw teeth by an axial gap (J), the outer jaw teeth of the second row being complementary to the second inner jaw teeth to ensure safety against failure of the first row.
  2. 2. The system (34) of claim 1, wherein the first row of outer claw teeth is an upper row of outer claw teeth intended to be located on one side of a blade (12) of the propeller blade (10), and the second row of outer claw teeth is a lower row of outer claw teeth.
  3. 3. The system (34) of claim 1, wherein the second row of outer claw teeth is an upper row of outer claw teeth intended to be located on one side of a blade of the propeller blade, the first row of outer claw teeth being a lower row of outer claw teeth.
  4. 4. A system (34) according to any one of claims 1 to 3, wherein the outer claw teeth of the first row and the outer claw teeth of the second row are axially spaced from each other by a space (E) intended to accommodate the first inner claw teeth or the second inner claw teeth, and the axial dimension (E1) of the space is greater than the axial thickness of those inner claw teeth.
  5. 5. A system (34) according to any one of claims 1 to 3, wherein the axial thickness (E2, E3) of the outer claw teeth of the first row of outer claw teeth is greater than the axial thickness of the outer claw teeth of the second row of outer claw teeth.
  6. 6. A system (34) according to any one of claims 1 to 3, wherein the outer claw teeth of the first and second rows have substantially the same inner diameter (Dint) and the same outer diameter (Dext).
  7. 7. A system (34) according to any one of claims 1 to 3, wherein the stationary ring (152) comprises an inner cylindrical surface (152 a) at an inner periphery of the stationary ring, the inner cylindrical surface (152 a) being configured to mate with an outer cylindrical surface (46 a) of the root (14) of the propeller blade (10) or an element mounted thereto by sliding during the double claw clutch, the inner cylindrical surface being complementary to the outer cylindrical surface and being located within the outer claw teeth of the first or second row.
  8. 8. The system (34) of claim 7, wherein the axial dimension of the inner cylindrical surface (152 a) is between 90% and 100% of the axial thickness (E2, E3) of an outer claw tooth of the first row of outer claw teeth or the maximum axial thickness of the retaining ring.
  9. 9. A system (34) according to any one of claims 1 to 3, wherein the system further comprises: a lower rolling guide bearing (54) extending around said axis (A) and mounted around a lower portion of said annular wall (58 a), -An upper rolling guide bearing (56) extending around said axis (a) and mounted around an upper portion of said annular wall (58 a).
  10. 10. The system (34) of claim 9 wherein at least one of the lower (54) and upper (56) rolling guide bearings has an inner ring of the rolling guide bearing integrated into the cup (58).
  11. 11. The system (34) of claim 9 wherein the upper rolling guide bearing (56) is mounted around the upper portion of the annular wall (58 a), the upper portion of the annular wall including the first and second inner claw teeth at an inner periphery of the upper portion and including threads at an outer periphery of the upper portion, a nut (78) being threaded onto the threads and axially supported on an outer ring of the upper rolling guide bearing (56).
  12. 12. A system (34) as claimed in any one of claims 1 to 3, wherein the system further comprises a locking ring (92) and an annular snap ring (100), the locking ring (92) being configured to be axially engaged between the third inner and outer claw teeth (82, 84) to prevent rotation of the ring with the double claw clutch within the cup (58), the annular snap ring (100) being mounted in the cup (58) to axially block the locking ring (92) in the cup (58).
  13. 13. An assembly comprising a system (34) according to any one of claims 1 to 12 and a variable pitch propeller blade (10), the propeller blade (10) comprising a blade (12) connected to a root (14), the root (14) comprising a body (24) housed in an annular barrel (26) extending around the axis (a) of the propeller blade, the axis being a pitch setting axis.
  14. 14. A turbine engine comprising at least one system (34) according to any one of claims 1 to 12 or an assembly according to claim 13.
  15. 15. The turbine engine of claim 14, being a turbine engine for an aircraft.
  16. 16. A method for installing a system (34) according to any one of claims 1 to 12, wherein the method comprises the steps of: a) Inserting the root (14) of the propeller blade (10) into the cup (58) of the system (34) by displacing the propeller blade (10) in a direction parallel to the axis (A), which is a pitch setting axis, B) Engaging the free end (28) of the root (14) in a recess (60) of the bottom wall (58 b) of the cup (58) to rotationally fix the cup (58) to the root (14) of the propeller blade (10), and C) -engaging the fixing ring (152) previously mounted or present around the root (14) of the propeller blade (10) in the cup (58), and-mounting the fixing ring (152) in the cup (58) and on the root (14) of the propeller blade (10) by means of the double claw clutch, to ensure an axial retention of the root (14) in the cup (58).

Description

System for controlling the pitch of the propeller blades of an aircraft turbine engine Technical Field The present invention relates to the field of aircraft turbine engines, and in particular to propulsive propellers of these turbine engines comprising variable pitch blades. Background The prior art includes, inter alia, documents FR-A1-3 017 163 and FR-A1-3 080 322. The aircraft turbine engine propeller may be ducted (e.g., in the case of a fan) or non-ducted (e.g., in the case of an open rotor architecture). The propeller includes blades, which may be of variable pitch. The turbine engine then includes a mechanism that enables the pitch angle of the blades to be changed to adapt the thrust produced by the propeller to different flight phases. The design of propeller blades involves a number of disciplines where the objectives often conflict with each other. The design of propeller blades must have optimal aerodynamic performance (i.e. provide thrust while maximizing efficiency), ensure mechanical strength of the blade (i.e. withstand mechanical constraints created by static and dynamic loads), while limiting mass and acoustic characteristics. In particular, improvements in the aerodynamic performance of the propeller tend to increase in the bypass Ratio (BPR), which translates into an increase in the outer diameter of the propeller and thus in the span of the blades. However, the increase in BPR occurs simultaneously with the decrease in fan pressure ratio (Fan Pressure Ratio, FPF). Thus, a pitch change system (variable pitch vanes) is typically required to make the propeller operable throughout the flight domain. There are various techniques for attaching variable pitch propeller blades and for controlling the angular pitch of such propeller blades. However, these techniques are relatively complex and expensive. Furthermore, in the event of problems with the blades, in particular in the event of damage, in particular when the propeller is not ducted, these techniques do not guarantee that the blades remain radially outwards with respect to the axis of rotation of the propeller. In the event of failure of the retaining means for the blades of the propeller, it is particularly important to ensure that the blades are retained to prevent them from projecting outwards and from striking the fuselage of an aircraft equipped with a turbine engine. Such a safety function called "failsafe (failsafe)" is not always present in the control systems of the prior art. Control systems that include this function typically include elements that themselves are prone to separation and impact with the fuselage of the aircraft. The greater the size and density of these elements, the greater the risk of damage to the fuselage and the greater the need for specific shields, which can affect the quality of the aircraft and thus the performance of the aircraft. Therefore, there is a need for a control system technology that integrates simple and efficient safety functions. Disclosure of Invention The invention relates to a system for controlling the pitch of the propeller blades of an aircraft turbine engine, characterized in that it comprises: A cup comprising an annular wall extending around an axis intended to set the axis for the pitch of the blade, the annular wall comprising a lower axial end enclosed by a bottom wall and an open upper axial end configured to enable the root of the blade to be mounted inside the cup, the bottom wall being configured to cooperate in a form-fitting manner with the free end of said root, such that the cup is rotationally fixed to the root around said axis, and A retaining ring extending about said axis and configured to be mounted about the root portion, the retaining ring being configured to be mounted within the cup portion and to cooperate with the root portion and an annular wall of the cup portion, respectively, to ensure axial retention of the root portion within the cup portion, And the stationary ring is a double claw clutch ring comprising two annular rows of outer claw teeth, a first of the rows of teeth being configured to engage with a complementary first inner claw tooth of the annular wall of the cup by the claw clutch and with the teeth by the axial support to ensure retention of the root in the cup, a second of the rows of teeth being configured to engage with a complementary second inner claw tooth of the annular wall of the cup by the claw clutch and spaced from the teeth by an axial gap to ensure safety in the event of failure of the first row of teeth. In this patent application, a double claw clutch ring is defined as a ring equipped with two annular rows of outer claw teeth. The teeth of each of these rows of teeth can be engaged by a dog clutch with a complementary row of internal teeth of the cup of the system. A dog clutch is a device that mounts one component in another component by two displacements of the components (by translating one component relative to the other