Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENTS OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
  • B64D35/00—Transmitting power from power plant to propellers or rotors; Arrangements of transmissions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/36—Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H1/00—Toothed gearings for conveying rotary motion
  • F16H1/02—Toothed gearings for conveying rotary motion without gears having orbital motion
  • F16H1/04—Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members
  • F16H1/06—Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members with parallel axes
  • F16H1/08—Toothed gearings for conveying rotary motion without gears having orbital motion involving only two intermeshing members with parallel axes the members having helical, herringbone, or like teeth
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H1/00—Toothed gearings for conveying rotary motion
  • F16H1/02—Toothed gearings for conveying rotary motion without gears having orbital motion
  • F16H1/20—Toothed gearings for conveying rotary motion without gears having orbital motion involving more than two intermeshing members
  • F16H1/22—Toothed gearings for conveying rotary motion without gears having orbital motion involving more than two intermeshing members with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/15—Load balancing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/40—Transmission of power
  • F05D2260/403—Transmission of power through the shape of the drive components
  • F05D2260/4031—Transmission of power through the shape of the drive components as in toothed gearing
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T50/00—Aeronautics or air transport
  • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

Definitions

• the present invention relates to a speed reducer with two intermediate transmission lines, in particular for a turbomachine.
• a turbomachine may comprise one or more mechanical speed reducers. This is particularly the case of a turboprop whose propeller is rotated by a turbine shaft via a speed reducer.
• the present invention essentially relates to a reducer with intermediate lines of transmission (also called compound reducer or "compound").
• such a speed reducer comprises an input line and an output line driven by the input line through two intermediate transmission lines.
• the power transmitted by the input line is separated between the intermediate lines before being transferred to the output line.
• the intermediate transmission lines are parallel and generally comprise each a shaft carrying an input gear engrained with the input line and an output gear engrained with the output line.
• a reducer of this type is a hyperstatic system. Without any particular arrangement, it is possible that an intermediate line passes the majority of the engine power, while the other intermediate line hardly passes power.
• the present invention proposes in particular to add to a reducer of this type charge distribution means to approach an equitable distribution of power between the two intermediate lines.
• the invention is realized by a speed reducer with two intermediate transmission lines, in particular for a turbomachine, comprising an input line and an output line driven by the input line via said lines. intermediate, these intermediate lines being substantially parallel to an axis of rotation of the input line, said reducer further comprising means for distributing charges between the intermediate lines, characterized in that said distribution means comprise a pinion integral with a shaft of the input line, the input line being movable in translation along said axis and comprising two helical outer teeth crowns whose helices are oriented in opposite directions, respectively cooperating respectively with a pinion of an intermediate line; .
• said sprockets connected to the intermediate lines are fixed in translation parallel to the axis;
• the two helical outer gear crowns have pitch angles of the helix substantially equal in absolute value
• the two helical external tooth crowns have the same diameter; the two crowns of helical external teeth are contiguous, so as to form chevrons;
• the two helical external tooth crowns have substantially the same extension along the axis of rotation;
• the axial extension of the pinion allows the displacement of only one element so as to provide a simple, effective and stable solution
• each helical external gear ring is oriented so that, during the transmission of a torque, an axial force is exerted on the latter by the pinion connected to the corresponding intermediate line, towards the other crown of external helical gears.
• the invention also relates to a turbomachine comprising at least one such speed reducer.
• the invention also relates to a method for transmitting a torque, in particular in a turbomachine, by means of a speed reducer comprising an input line, two intermediate transmission lines, and an output line driven by the input line via said intermediate lines, the intermediate lines being substantially parallel to an axis of rotation of the input line, the method of adjusting the axial position of the input line along said axis, in order to equalize the charges between the two intermediate lines.
• the adjustment of the axial position of the input line is performed automatically by the gearbox, and results from a balancing of the couples transmitted by the input line to the intermediate lines, respectively.
• FIG. 1 is a very schematic view of a speed reducer with two intermediate transmission lines, viewed from the side,
• FIG. 2 is a very schematic view of a speed reducer with two intermediate transmission lines, viewed from the front
• FIGS. 3 and 4 are diagrammatic partial and top views of a gearbox of the aforementioned type according to the invention, FIG. 3 showing a non-homogeneous distribution of the loads between the intermediate lines and FIG. 4 showing a homogeneous distribution of the loads. between the intermediate lines, and
• FIG. 5 is a highly diagrammatic half-view in axial section of a line equipped input load distribution means according to the invention
• FIG. 1 very schematically represents a gear reducer 1 with two intermediate transmission lines, this gear unit 1 comprising essentially four parts: an input line 2, an output line 3 and two intermediate transmission lines 4 , Which are driven by the input line 2 and in turn drive the output line 3.
• the various parts 2, 3, 4, 5 of the gearbox 1 are generally mounted in a housing of the gearbox which is not shown here, this casing having a first orifice for the passage of the input line 2 and its connection to a first element of a turbomachine for example, and a second orifice for the passage of the output line 3 and its connection to a second element of the turbomachine.
• the first element is for example a turbine shaft of the turbomachine and the second element is a drive shaft of a propeller of this turbomachine in the case where the latter is a turboprop.
• the input line 2 comprises a shaft 6 carrying a pinion 7 with external teeth.
• the pinion 7 and the shaft 8 are coaxial and rotate about the same axis denoted B. In the example shown, they are driven in the direction of rotation ⁇ , counterclockwise, by the shaft of the turbomachine.
• the output line 3 comprises a shaft 8 carrying a pinion 9 with external teeth.
• the pinion 9 and the shaft 8 are coaxial and rotate about the same axis denoted A. They rotate here in the same direction of rotation ⁇ as the pinion 7 and the shaft 6 of the input line 2, but to a different speed.
• the input and output lines 2, 3 are parallel. Their axes of rotation B, A are therefore parallel.
• the intermediate transmission lines 4, 5 are substantially parallel.
• Each line 4, 5 comprises a shaft 10, 1 1 which carries an input gear 12, 13 at one end and an output gear 14, 15 at a second end.
• the output gears 14, 15 are meshing with the pinion 9 of the output line 3.
• the input gears 12, 13 are meshing with the pinion 7 of the input line 2.
• the pinions 12, 13, 14, 15 are external teeth.
• Each shaft 10, 1 1 and its pinions 12, 13, 14, 15 are coaxial and rotate about the same axis denoted C, D parallel to the axes A and B. They rotate in a direction of rotation opposite to that ⁇ of the 6 of the input line 2.
• their speeds of rotation are substantially the same, the pinions 13, 14 respectively having the same diameter ratios with helical external crowns 7a, 7b corresponding on the pinion 7.
• this type of gearbox 1 is a hyperstatic system and it is possible that an intermediate line, for example 10, passes the majority of the engine power, while the other intermediate line 1 1 practically passes. no power.
• This poor distribution of power or loads may be due to the games between the gears.
• the pinions 14, 15 are in contact at the points G, H with the pinion 9, and the pinion 12 of one of the intermediate lines 4 is in contact at the point E with the pinion 7, it is difficult to ensure the absence of play at F, between the pinion 7 and the pinion 13 of the other intermediate line 5.
• the invention proposes a solution to this problem by equipping the gear unit 1 with means for distributing the charges between the intermediate lines 4, 5.
• the pinion 7 comprises a first and a second ring 7a, 7b of helical external teeth, of axis of revolution of the axis B, each meshing respectively the pinions 12, 13 of the intermediate lines 10, 1 1, the latter being respectively left and right in the figures.
• the winding direction of the helices of the teeth of the two rings 7a, 7b are opposite.
• the two helical toothed crowns 7a, 7b are cylindrical, that is to say that the teeth are formed on a cylinder.
• the two tooth crowns 7a, 7b have the same diameter. In this way, it is not necessary to axial displacement of the gears of intermediate lines or intermediate lines to allow contact with the teeth of the gears of the intermediate lines.
• the pinions 12, 13 of the intermediate lines 4, 5 also have helical external teeth, with a pitch and a direction of winding of the helix adapted to cooperate with the helical crown gear 7a, 7b corresponding.
• the pinion 7 is here movable along the axis B of the input line 2, relative to the housing of the gearbox 1, not shown.
• the pinions 12, 13 of the intermediate lines 4, 5 are, in turn, fixed relative to said housing.
• the pinion 7 is integral with the shaft 6, bearings 16, 17 placed axially on either side of the pinion 7 maintain the axis 6 centered on the axis B of the input line while allowing him to move axially.
• the inner ring 18a, 18b of each bearing 16, 17 is integral with the shaft 6 while the outer ring 19a, 19b is fixed relative to the housing, not shown.
• the outer ring 19a, 19b is smooth and the rolling elements, preferably rollers 20a, 20b, allow axial movements of the inner ring 18a, 18b by sliding axially in the outer ring 19a, 19b.
• the end of the shaft 6 comprises for example splines 21 engaged in splines 22 complementary to a sleeve 23 for connecting the input line 2 of the gearbox 1 to the shaft of the turbine, not shown.
• the flutes also allow the pinion 7 to be movable relative to the shaft of the turbine. This axial freedom can also be provided by an additional flexible element.
• the rings 7a, 7b of the pinion 7 of the input line are spaced axially and their teeth have substantially the same axial extension.
• this example is not limiting.
• the two helical gear crowns can be contiguous and thus form a single herringbone toothing on the input gear 7.
• the gears 12, 13 of the intermediate lines 4, 5 can also be slightly offset with respect to the toothed crowns 7a. 7b and / or be narrower axially, so that the displacement of the inlet line 2 does not bring them into contact with the ring gear 7b, 7b cooperating with the pinion of the other intermediate line.
• the points of application E, F of the axial forces f1, f2 are axially offset. They therefore create a torque along an axis perpendicular to the B axis of the input line 2. The forces generated by this torque are caught at the bearings 17, 18, which allows to load the bearings. This avoids sliding problems of the rolling elements 20a, 20b in the bearings 17, 18.
• the exemplary mode of implementation presented is not limiting, in particular with regard to the geometric characteristics of the gears 7, 12, 13 participating in the process of distribution of loads or with regard to the torque ratios transmitted to each line intermediate 4, 5 through the input line 2.
• This example illustrates a method of transmitting a torque, by means of a speed reducer (1) type "compound”, of adjusting the axial position of the input line (2) so as to equalize the charges between the two intermediate lines (4, 5).
• the axial displacement d of the input line 2 results from a balancing of the couples transmitted by the input line (2) to the intermediate lines (4, 5), respectively.

Applications Claiming Priority (2)

Publications (1)

Family

ID=53274640

Family Applications (1)

Country Status (8)

Families Citing this family (4)

Family Cites Families (15)

• 2015
  • 2015-03-27 FR FR1552581A patent/FR3034158B1/fr active Active
• 2016
  • 2016-03-25 CA CA2980430A patent/CA2980430A1/fr not_active Abandoned
  • 2016-03-25 US US15/560,125 patent/US20180100562A1/en not_active Abandoned
  • 2016-03-25 EP EP16719445.5A patent/EP3274609A1/de not_active Withdrawn
  • 2016-03-25 JP JP2017549677A patent/JP2018515723A/ja active Pending
  • 2016-03-25 CN CN201680017958.9A patent/CN107406147A/zh active Pending
  • 2016-03-25 RU RU2017133005A patent/RU2720600C2/ru active
  • 2016-03-25 WO PCT/FR2016/050694 patent/WO2016156725A1/fr active Application Filing

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