EP4259375A1

EP4259375A1 - Method, device and control unit for establishing a press fit

Info

Publication number: EP4259375A1
Application number: EP22703616.7A
Authority: EP
Inventors: Nicola ACCIALINI; Matti Meissner; Christos Kallianteris
Original assignee: Aerospace Transmission Technologies GmbH
Current assignee: Aerospace Transmission Technologies GmbH
Priority date: 2021-02-16
Filing date: 2022-02-02
Publication date: 2023-10-18
Also published as: WO2022175087A1; DE102022102422A1

Abstract

A method, a device and a control unit for establishing or for releasing a press fit between at least one first component (42) and at least one second component (34) and at least one wedge sleeve (43) arranged in between are described. During the producing or the releasing of the press fit, hydraulic fluid is introduced under pressure in each case between an outer surface of the wedge sleeve (43) and an inner side of the second component (34) and/or between an inner side of the wedge sleeve (43) and an outer side of the first component (42). An axial actuating force is determined during the establishing or the releasing of the press fit. The pressure at which the hydraulic fluid is introduced is varied in an automatically regulated manner, in the case of the presence of an axial actuating force greater than or equal to a predefined upper limit value, until the axial actuating force is lower than the predefined upper limit value.

Description

Method, device and control device for producing a press fit

The present disclosure relates to a method and an apparatus for producing an interference fit between at least a first component and at least a second component and at least one wedge sleeve arranged therebetween. Furthermore, the present disclosure relates to a control device for carrying out the method and a corresponding computer program product.

Devices known from practice for producing a press fit between a first component and a second component and at least one wedge sleeve arranged in between are used to connect the two components to one another in a rotationally fixed manner by means of the wedge sleeve. The wedge sleeve is usually inserted radially in the axial direction between an area of the first component and an area of the second component via an actuating element of a device that includes a press or the like. For this purpose, the actuating element can be displaced axially by an actuator that can often be actuated hydraulically. In this case, the first component is designed, for example, as a bearing pin of a planet gear of a planetary gear, while the second component is a planet carrier. To connect the bearing pin to the planet carrier in a rotationally fixed manner, wedge sleeves designed as clamping sleeves are inserted or pressed in between the end areas of the bearing pin and bearing areas of the planet carrier, which radially encompass the end areas of the bearing pin.

For this purpose, a wedge sleeve is applied with its one end face to the two components and, starting from its other end face, is acted upon by the actuator or the actuating element with the axial actuating force required for insertion and thereby inserted between the bearing bolt and the planetary carrier.

The splined sleeves are inserted between the bearing pin and the splined sleeve and between the splined sleeve and the planet carrier by using liquid nitrogen and/or injecting high pressure oil. The devices described before for making press fits are also suitable for resolving the press fits. The devices are used for producing and releasing press fits in various areas of application. In particular, the devices are used in the manufacture of ship propellors, steering units, gears, flywheels, clutch hubs, roller bearings, hydraulic pumps and the like.

The devices used are either manually or automatically operated during the production of press fits or the release of press fits.

If the press fit is made or released by manual operation of such a device, it is the task of the operator operating the device to apply oil or hydraulic fluid at high pressure between the facing inner and outer surfaces of the components to be joined and of the wedge sleeve arranged in between. This is to ensure that the mutually facing surfaces of the components and the wedge sleeve are expanded or shrunk during the joining process and the friction is reduced. At the same time, for example, the wedge sleeve is adjusted by the press to its desired end position.

It is necessary for the radial pressure with which the hydraulic fluid is introduced to be high enough to keep the loads on the components and the wedge sleeve within permissible ranges. These areas are usually determined empirically. The manual process is characterized by a high level of flexibility. On the other hand, manual joining and loosening of press connections cannot be carried out with the desired reproducibility.

Joining and loosening processes for press fittings can be carried out reproducibly to the desired extent using automatically operable devices. However, known systems are not able to adapt to different starting conditions of the joining and detaching process in the required manner. Furthermore, both manually operated and automatically operated devices are based on the disadvantage that the process parameters for carrying out joining and detaching processes for press assemblies usually have to be determined using complex and cost-intensive test series.

In the case of automatically operated devices, input parameters or process parameters are stored in such a way that they cannot be changed after they have been entered, which is why there is then no longer the possibility of adapting them to different starting conditions.

In fact, however, the initial conditions can vary greatly. If, for example, the wedge sleeve is not pre-installed to the required extent relative to the components, the axial setting force to be applied to create the interference fit can increase significantly compared to proper pre-installation of the wedge sleeve. In addition, higher joining forces are required to produce an interference fit if the components to be joined or their contact surfaces are not sufficiently cleaned before the start of the process. Hard particles that are already present in the area of the facing mating surfaces of the components and the wedge sleeve increase the axial force immediately and cause irreversible damage in the area of the components and the wedge sleeve during the joining process, which is undesirable.

In addition, there is the possibility that the radial pressures with which the hydraulic fluid is respectively introduced differ greatly from one another both for the worst-case scenario and for the best-case scenario. This results from different component dimensions of the components to be joined, which in turn depend on the so-called tolerance stack.

Furthermore, there is also the possibility that the coefficient of friction of prepared wedge sleeves varies greatly and the initial conditions of earlier joining processes are combined at random, which increases the variance of the process parameters and the initial conditions. Based on the prior art described above, the object of the present disclosure is to provide a method and a device for producing or releasing an interference fit between at least one first component and at least one second component and at least one wedge sleeve arranged therebetween , by means of which the disadvantages described in more detail above are avoided. In addition, a control unit designed to carry out the method and a computer program product to carry out the method are to be specified.

This object is achieved with a method and a device with the characteristics of patent claim 1 and 11 respectively. A control device and a computer program product are also the subject of the further independent claims. Advantageous developments are the subject of the subclaims and the following description.

According to a first aspect, a method for producing or releasing a press fit between at least one first component and at least one second component and at least one wedge sleeve arranged in between is proposed. Hydraulic fluid under pressure is introduced between an outer surface of the wedge sleeve and an inner side of the second component and/or between an inner side of the wedge sleeve and an outer side of the first component during the creation or release of the interference fit. An axial positioning force is determined during the manufacture or release of the press fit. In addition, the pressure with which the hydraulic fluid is introduced is automatically varied when there is an axial actuating force greater than or equal to a predefined upper limit value until the axial actuating force is less than the predefined upper limit value.

By means of the method according to the present disclosure, the pressure with which hydraulic fluid or oil is injected between the mating surfaces of the components and the wedge sleeve, around the mating surfaces or mating surfaces between, for example, a bore of the first component and an outer surface of the wedge sleeve and between them an inner surface of the wedge socket and an outer surface of the second component move away from each other and thus reduce or completely eliminate the existing friction, varies automatically depending on the operating state. The next step is to move the wedge sleeve to the final position where the desired interference fit is present or to slide it out of that final position and release the interference fit.

The level of the pressure or the radial pressure of the hydraulic fluid is accordingly adjusted and changed during the implementation of the method according to the present disclosure.

This procedure avoids both plastic deformations in the area of the components and the wedge sleeve as well as the undesired generation of chips. In particular, due to high cleanliness requirements, the generation of chips should be avoided as far as possible, especially during the production of the press fit.

Furthermore, the method according to the present disclosure ensures that process data on which the process of producing or releasing the press connection is based can be determined with significantly less effort than in the case of known solutions. In addition, the method offers improved process control due to the adaptive control on which the method is based. The procedure described is also characterized by a high level of process flexibility, since different initial conditions when joining or detaching the components and the wedge sleeve can be taken into account in a simple manner.

The proposed control strategy can be used to create or release press fits in various application areas. For example, there is the possibility of press fits in the area of bearings, clutches, gears, crankshafts, railway wheels, planetary gears and the like to produce or solve the proposed scope. It can be provided that by means of the method according to the present disclosure, so-called planet bolts, on which at least one planet gear is rotatably mounted, are connected in bores of a planet carrier via wedge sleeves to the planet carrier in a rotationally fixed manner.

In such planetary gears, the planetary carrier usually rotates, subjecting the system to high centrifugal loads. In order to be able to ensure the non-rotatable connection between such planet bolts and a planet carrier despite the high centrifugal loads acting on them, wedge sleeves are used in order to produce correspondingly high press fits. It can be provided that methods for assembling and disassembling planetary gears that are used in the aerospace industry are used.

Furthermore, in the method according to the present disclosure, which includes adaptive control, the radial pressure of the hydraulic fluid and the axial positioning force are correlated in real time and the radial pressure of the hydraulic fluid is corrected as needed. For this purpose, the level of the axial actuating force is automatically defined by the system logic. This means that with little control and regulation effort it can be guaranteed that the axial force applied in each case does not exceed a predefined limit value, above which residual stresses in the area of the wedge sleeves, chip formation and, in addition, plastic deformation in the area of the components of the wedge sleeves, can be controlled or avoided are. This is achieved in that when an axial actuating force is determined which exceeds the predefined limit value, the control of the method automatically varies the radial pressure of the hydraulic fluid in order to reduce the friction between the mating surfaces of the components and the wedge sleeves.

In the present case, the term interference fit is understood to mean interference fits in which the maximum dimension of the bore is always smaller than the minimum dimension of the shaft. In the case of application under consideration, this means that the oversize is present between the components in the assembled operating state of the wedge sleeve between the facing mating surfaces of the components and the wedge sleeve. In a variant of the method according to the present disclosure, the joining process is ended if an axial actuating force that is less than a predefined lower limit value is determined during the production of the press fit. This avoids in a simple way that insufficient press fits are produced.

Furthermore, it can be provided that the joining process is ended if an axial actuating force greater than a further predefined upper limit value is determined during the production of the press fit. In this case, the predefined upper limit value can be greater than the upper limit value of the actuating force and can have a value above which plastic deformations occur in the area of the components and/or the wedge sleeve. This in turn means that during the manufacture of the press fit, plastic deformations in the area of the components and/or in the area of the wedge sleeve are avoided with little control and regulation effort.

In addition, it can also be provided that the joining process is ended if the pressure exceeds an upper limit value during the production of the press fit. This procedure in turn ensures in a simple manner that irreversible damage, such as plastic flow, in the area of the components and/or the wedge sleeve is avoided as a result of the pressure applied.

The upper limit and/or the lower limit of the actuating force can be varied depending on a displacement path of the wedge sleeve relative to the components or depending on a displacement path of one of the components relative to the other component and relative to the wedge sleeve. This in turn makes it easy to take into account that the axial actuating force increases or decreases as a function of the adjustment path when producing or releasing the press fit and that the joining or dissolving process is carried out with the currently required axial actuating force.

In a variant of the method according to the present disclosure it is provided that a course of the axial force is determined as a function of an axial adjustment path of the wedge sleeve relative to the components or as a function of a displacement path of one of the components relative to the other component and ge compared to the wedge sleeve. This also makes it easy to take into account that the axial actuating force increases or decreases as a function of the adjustment path when producing or loosening the press fit and the joining or loosening process is carried out with the currently required axial actuating force.

The course of the actuating force can be determined using a numerical model that is calibrated as a function of empirically determined data. By means of this approach, adaptive control is made available with which the radial pressure of the hydraulic fluid and the axial actuating force can be correlated in real time and the radial pressure of the hydraulic fluid can be corrected as required. The numerical model, calibrated using the empirically determined data, depicts the joining and loosening process between the components and the wedge sleeve. In addition, varying initial conditions, such as insufficiently cleaned components, an undesired inclination of the components to be joined to one another, any chips or the like that may be present can be easily taken into account by the adaptive control.

The pressure of the hydraulic fluid can be left at the pressure level of the upper limit value for a defined period of time. It can be provided that during the defined period of time a check is made as to whether the actuating force falls to values less than the upper limit value within the defined period of time. If the test result is positive, the pressure can be reduced again, whereas the joining process can be ended if the test result is negative. It can thus be guaranteed with little effort that a joining or a loosening process is only ended when it is determined that the actuating force is permanently greater than the upper limit value.

In a variant of the process according to the present disclosure that can be carried out with little control and regulation effort, the pressure is reduced when the another upper limit of the pressure, which is smaller than the upper limit of the pressure, kept constant.

The first component can be a planetary bolt on which a planetary gear of a planetary gear unit is rotatably mounted. The second component can be designed as a planetary carrier. The planet pin can be arranged at the ends in bores of the planetary carrier. The at least one wedge sleeve can be pressed in to produce the press fit between the planet pin and the planet carrier by applying the axial force and pushed out to loosen the press fit by means of the axial force.

According to a further aspect of the present disclosure, a device is proposed for producing or releasing an interference fit of an interference fit between at least a first component and a second component and at least one wedge sleeve arranged between the components. The device includes a pressing device for applying an axial actuating force to the components and to the wedge sleeve. Furthermore, the device comprises at least one sensor for determining the axial actuating force. In addition, the device according to the present disclosure is designed with a high-pressure hydraulic fluid injection device for introducing hydraulic fluid under pressure between an outer surface of the wedge sleeve and an inner side of the second component and/or between an inner side of the wedge sleeve and an outer side of the first component. In addition, the device has at least one pressure measurement sensor for determining the pressure and a control device for carrying out the method described in more detail above.

According to a further aspect of the present disclosure, a control unit is proposed which is designed to carry out the method according to the present disclosure. The control unit includes, for example, means that are used to carry out the method. These means can be hardware-side means and software-side means. The hardware-side means of the control device are, for example, data interfaces in order to communicate with the assemblies of the device involved in the implementation of the method exchange. Additional hardware means are, for example, a memory for data storage and a processor for data processing. Software-side means can be, inter alia, program modules for carrying out the method.

To carry out the method, the control device can be designed with at least one receiving interface which is designed to receive signals from signal generators. The signal generators can, for example, be in the form of sensors that record measured variables and transmit them to the control unit. A signal transmitter can also be referred to as a signal sensor. In this way, the receiving interface can receive a signal from a signal generator, which signals that a press fit is to be produced or released. The signal can be generated by an operator, for example, by actuating an operating element via which such a determination can be requested. Furthermore, the signal can also be generated by a manufacturing strategy that is activated and implemented in the area of the control unit or in the area of another control unit of a machine tool or the like.

The control device can also have a data processing unit in order to evaluate and/or process the received input signals or the information of the received input signals.

The control unit can also be designed with a transmission interface that is designed to output control signals to actuators. An actuator is understood to mean actuators that implement the commands of the control unit. The actuators can, for example, be in the form of hydraulic, electrical or mechanical actuators which generate or make available the axial actuating force required to produce or release the press fit and the pressure of the hydraulic fluid.

If the control unit recognizes that a press fit between the components and the wedge sleeve is to be created or loosened, the control unit applies hydraulic fluid under pressure between an outer surface of the wedge sleeve and an inner surface of the wedge sleeve while the press fit is being created or loosened second component and / or introduced between an inside of the wedge sleeve and an outside of the first component. Furthermore, the control device is used to determine an axial actuating force during the production or the loosening of the press fit. The pressure with which the hydraulic fluid is introduced is automatically varied by means of the control device when an axial actuating force is greater than or equal to a predefined upper limit value until the axial actuating force is smaller than the predefined upper limit value.

This in turn ensures that a radial pressure of the hydraulic fluid and an axial actuating force can be correlated in real time and the radial pressure can be corrected accordingly if necessary.

The aforementioned signals are to be considered as exemplary only and are not intended to limit the present disclosure. The detected input signals and the output control signals can be transmitted via a data bus. The control device or the control unit can be designed, for example, as a central electronic control unit of a machine tool.

The solution proposed here can also be embodied as a computer program product which, when it runs on a processor of a control device, instructs the processor in terms of software to carry out the associated method steps in accordance with the present disclosure. In this context, the subject matter of the present disclosure also includes a computer-readable medium on which a computer program product described above is stored in a retrievable manner.

It will be understood by those skilled in the art that a feature or parameter described in relation to one aspect above may be applied to any other aspect, provided they are not mutually exclusive. Furthermore, any feature or parameter described herein may be applied to any aspect and/or combined with any other feature or parameter described herein, provided they are compatible not mutually exclusive. Embodiments will now be described by way of example with reference to the figures.

It shows:

1 is a longitudinal sectional view of a gas turbine engine;

Figure 2 is an enlarged partial longitudinal sectional view of an upstream portion of a gas turbine engine;

3 is an isolated view of a transmission for a gas turbine engine;

4 shows a highly schematized longitudinal view of a device for producing or releasing an interference fit between at least one first component and at least one second component and at least one wedge sleeve arranged between them;

FIG. 5 shows an enlarged view of an area V identified in more detail in FIG. 4;

6 shows a schematic partial representation of a first component and a second component as well as a wedge sleeve arranged between them, which are to be connected to one another via a press fit;

7 several curves of an axial actuating force over an axial adjustment path of a wedge sleeve relative to components or as a function of an axial adjustment path of one of the components relative to the other component and relative to the wedge sleeve;

FIG. 8 several curves of various process parameters of the device according to FIG. 4 during the production or release of a press fit between the planet bolt and the planet carrier of the planetary gear according to FIG. 3; and 9 shows a representation corresponding to FIG. 8 of further curves of various process parameters of the device according to FIG.

Fig. 1 depicts a gas turbine engine 10 having a main axis of rotation 9. The engine 10 includes an air intake 12 and a thrust fan 23 that creates two airflows: a core airflow 111 and a bypass airflow 122. The gas turbine engine 10 includes a core 11 that Core air flow 111 absorbs. The engine core 11 includes, in axial flow order, a low pressure compressor 14, a high pressure compressor 15, a combustor 16, a high pressure turbine 17, a low pressure turbine 19, and a core exhaust nozzle 20. An engine nacelle 21 surrounds the gas turbine engine 10 and defines a bypass duct 22 and a bypass exhaust nozzle 18. The bypass air flow 122 flows through the bypass duct 22. The fan 23 is attached via a shaft 26 and an epicycloidal gear 30 to the low-pressure turbine 19 and is driven thereby. The shaft 26 is also referred to as the core shaft.

In use, the core air stream 111 is accelerated and compressed by the low pressure compressor 14 and passed into the high pressure compressor 15 where further compression occurs. The compressed air discharged from the high-pressure compressor 15 is fed into the combustor 16, where it is mixed with fuel and the mixture is burned. The resultant hot combustion products then propagate through and thereby drive the high and low pressure turbines 17, 19 before being expelled through the nozzle 20 to provide some thrust. The high pressure turbine 17 drives the high pressure compressor 15 through a suitable connecting shaft 27, also referred to as the core shaft. The fan 23 generally provides the majority of the thrust. The epicycloidal gear 30 is a reduction gear.

An exemplary arrangement for a geared fan gas turbine engine 10 is shown in FIG. The low pressure turbine 19 (see FIG. 1) drives the shaft 26 which is coupled to a sun gear 28 of the epicycloidal gear assembly 30. A plurality of planetary gears 32, which are coupled to one another by a planetary carrier 34, are located radially outwards from the sun gear 28 and mesh with it and are each arranged rotatably on components or carrier elements 42 which are non-rotatably connected to the planetary carrier 34. The planetary carrier 34 constrains the planetary gears 32 to orbit synchronously about the sun gear 28 while allowing each planetary gear 32 on the carrier members 42 to rotate about its own axis. The planetary carrier 34 is coupled to the fan 23 via linkage 36 in such a way as to drive its rotation about the engine axis 9 . An Au ßenrad or ring gear 38, which is coupled via linkage 40 to a stationary support structure 24, is located radially outward of the planetary gears 32 and meshes there with.

It is noted that the terms "low-pressure turbine" and "low-pressure compressor" as used herein may be construed to mean the lowest-pressure turbine stage and the lowest-pressure compressor stage, respectively (i.e. not including the fan 23) and/or the turbine and compressor stages connected together by the connecting shaft 26 at the lowest speed in the engine (i.e. not including the transmission output shaft driving the fan 23). In some writings, the "low-pressure turbine" and "low-pressure compressor" referred to herein may alternatively be known as the "intermediate-pressure turbine" and "intermediate-pressure compressor." Using such alternative nomenclature, the fan 23 may be referred to as a first stage or lowest pressure stage.

The epicycloidal gear 30 is shown in more detail in FIG. 3 by way of example. The son gear 28, the planet gears 32 and the ring gear 38 each include teeth around their periphery for meshing with the other gears. However, for the sake of clarity, only exemplary portions of the teeth are shown in FIG. Although four planetary gears 32 are illustrated, those skilled in the art will recognize that more or fewer planetary gears 32 may be provided within the scope of the claimed invention. Practical applications of an epicycloidal gear 30 generally include at least three planetary gears 32. The exemplified in Fig. 2 and 3 epicycloidal gear 30 is a planetary gear, in which the planet carrier 34 is coupled via linkage 36 to an output shaft, wherein the ring gear 38 is fixed. However, any other suitable type of epicycloidal gear 30 may be used. As another example, the epicycloidal gear 30 may be a star arrangement in which the planetary carrier 34 is held fixed while allowing the ring gear (or ring gear) 38 to rotate. With such an arrangement, the fan 23 is driven by the ring gear 38 . As another alternative example, the gear 30 may be a differential gear in which both the ring gear 38 and the planet carrier 34 are allowed to rotate.

It should be understood that the arrangement shown in Figures 2 and 3 is exemplary only and various alternatives are within the scope of the present disclosure. For example only, any suitable arrangement for positioning the transmission 30 within the engine 10 and/or connecting the transmission 30 to the engine 10 may be used. As another example, the connections (e.g., the linkages 36, 40 in the example of FIG. 2) between the transmission 30 and other parts of the engine 10 (such as the input shaft 26, the output shaft and the fixed Structure 24) have some degree of rigidity or flexibility. As another example, any suitable arrangement of bearings between rotating and stationary parts of the engine (e.g., between the input and output shafts of the transmission and fixed structures such as the transmission case) may be used, and the disclosure is not be limited to the exemplary arrangement of FIG. For example, those skilled in the art will readily appreciate that the output and support linkage arrangement and bearing locations for a star configuration (described above) of the transmission 30 would typically differ from those exemplified in FIG.

Accordingly, the present disclosure extends to a gas turbine engine having any arrangement of gear types (e.g., radial or planetary), support structures, input and output shaft layout and bearing positioning.

Optionally, the transmission can drive secondary and/or alternative components (e.g., the intermediate pressure compressor and/or a booster).

Other gas turbine engines to which the present disclosure may have application may have alternative configurations. For example, such engines may have an alternative number of compressors and/or turbines and/or an alternative number of connecting shafts. As a further example, the gas turbine engine shown in Figure 1 has a split flow nozzle 20, 22, meaning that the flow through the bypass duct 22 has its own nozzle which is separate from the engine core nozzle 20 and radially outward therefrom. However, this is not limiting and any aspect of the present disclosure may also apply to engines where flow through bypass duct 22 and flow through core 11 occur before (or upstream of) a single nozzle, referred to as a mixed flow nozzle can be mixed or combined. Either or both nozzles (whether mixed or split flow) may have a fixed or variable area. For example, although the example described relates to a turbofan engine, the disclosure may apply to any type of gas turbine engine, such as a turbofan engine. an open rotor (where the blower stage is not surrounded by an engine nacelle) or a turboprop engine.

The geometry of the gas turbine engine 10 and components thereof is or are defined by a conventional axis system having an axial direction (which is aligned with the axis of rotation 9), a radial direction (in the direction from bottom to top in Fig. 1) and a Circumferential (perpendicular to the view in Fig. 1) includes. The axial, radial and circumferential directions are perpendicular to one another.

FIG. 4 shows a longitudinal sectional view of a device 40 which includes a pressing device 41 . Furthermore, the planetary carrier 34 and that to be connected to it Component or the planetary pin 42 for a planetary wheel 32 of the transmission 30 rotatably mounted thereon. 4 also shows clamping elements or wedge sleeves 43, 44, an axially adjustable actuator 45 and an actuating element 46 of the pressing device 41 that can be moved axially via the actuator 45, via which the wedge sleeves 43, 44 can be moved radially in the axial direction A or B between areas of the planet carrier 34 and areas of the planet pin 42 can be inserted. The actuating element 46 reaches through the actuator 45, the planetary carrier 34 and the planetary pin 42 in the axial direction A or B.

In addition, the actuating element 46 interacts with the actuator 45 at one end and is designed with a cover element 47 at the other end. About the cover element 47 and the wedge sleeve 44 is the actuator 46 with the planet carrier 34 and the planet pin 42 in operative connection. The wedge sleeve 44 is positioned axially between the cover element 47 and the planet carrier 34 and the planet pin 42 po, while the wedge sleeve 43 is arranged between the planet carrier 34 and the tarpaulin pin 42 and a housing area 48 of the actuator 45 . In addition, the actuating element 46 and the actuator 45 for inserting the wedge sleeves 43 and

44 between the planet carrier 34 and the planet pin 42 in an axi alen distance between the cover member 47 and the housing portion 48 of the Ak sector 45 reducing scope relative to the planet carrier 34 and the planetary bolt zen 42 movable.

In the present case, the actuator 45 is designed as a hydraulic actuator, by means of which the actuating element 46 can be displaced in the axial direction A. Furthermore, the actuator 45 is designed in such a way that the actuator 45 is also moved in the axial direction B towards the planetary carrier 34 and the planetary pin 42 during the axial adjustment of the actuating element 46 . The adjustment paths of the adjustment element 46 and the actuator are

45 limited by housing-side stops 49, 50 in the area of the actuator 45. The stop 49 interacts with a nut 51 screwed onto the adjusting element 46, while the adjustment paths of the adjusting element 46 and of the actuator 45 are limited in the joining direction of the two wedge sleeves 43 and 44 by means of an enlarged diameter region 52 of the adjusting element 46 that interacts with the stop 50 are. During the joining process or during the insertion of the wedge sleeves 43 and 44 between the planetary carrier 34 and the planetary bolt 42, the wedge sleeves 43 and 44 are displaced by the axial displacement of the actuating element 46 on the actuator side and the associated adjustment of the actuator 45 starting from in the axial direction of the planetary carrier 34 and the planetary pin 42 from each other facing pages 53, 54 are inserted.

If only the wedge sleeve 43 or the wedge sleeve 44 is to be pushed in between the planetary carrier 34 and the planetary pin 42 during a joining process via the device 40 by the above-described actuator-side adjustment of the actuating element 46 or the adjustment of the actuator 45, there is a simple way of either between the cover element 47 and the planet carrier 34 and/or the planet pin 42 or between the housing area 48 and the planet pin 42 and/or the planet carrier 34 a sleeve-shaped or ring-shaped spacer element 55A or 55B or 56A or 56B to be provided. The spacer elements 55A or 55B or 56A or 56B prevent a reduction in the distance between the cover element 47 and the side 54 or between the housing area 48 and the side 53 and only the wedge sleeve 43 or the wedge sleeve 43 between the planet carrier 34 and the planet pin 42 is inserted to the desired extent.

FIG. 5 shows an enlarged sectional view of region V, which is identified in more detail in FIG. 5 shows that the wedge sleeve 43, which in principle has the same structure as the wedge sleeve 44, is a clamping sleeve which is cylindrical in the area of its outer circumference 57 and conical in the area of its inner diameter 58 . The inner diameter 58 of the wedge sleeve 43 decreases starting from the side 59 facing the components or the planet carrier 34 and the planet pin 42 in the direction of the side 60 facing away from the components or the planet carrier 34 and the planet pin 42 . In addition, the planet pin 42 in the joining area with the wedge sleeve 43 has a we at least approximately adapted to the wedge sleeve 43 conical outer contour 61, while the planet carrier 34 is designed in the joining area with the wedge sleeve 43 with a zy-cylindrical inner contour. Both the planetary carrier 34 and the planetary pin 42 are formed in the joining area with the wedge sleeve 44 as described in more detail above, as in the joining area with the wedge sleeve 43 .

The planetary pin 42 is provided with lines 62 which are in overlap with a line 63 of the actuating element 46 when the actuating element 46 reaches a defined position Po. Lines 64 are provided in the wedge sleeve 43 via which hydraulic fluid can be guided from the joining area between the wedge sleeve 43 and the planet pin 42 into the joining area between the wedge sleeve 43 and the planet carrier 34 . By introducing the hydraulic fluid via the lines 63 and 62 into the joining area between the wedge sleeve 43 and the planetary pin 42 or between the wedge sleeve 43 and the planetary carrier 34, the planetary pin is located between the planetary pin 42 and the planetary carrier 34 while the wedge sleeve 43 is being pushed in 42 can be reversibly constricted on the circumference and the wedge sleeve 43 and the planet carrier 34 can be reversibly widened, while the wedge sleeve 43 is reversibly compressed in the outer circumference 57 . The wedge sleeve 43 can thus be inserted between the planet bolt 42 and the planet carrier 34 with low axial joining forces.

At the end of the joining process, the hydraulic pressure applied is reduced or switched off, whereby the previously reversible expansion of the planetary carrier 34 and the reversible constriction of the planetary pin 42 decrease and the wedge sleeve 43 provides the desired non-rotatable connection between the planetary carrier 34 and the planetary pin 42 in the form of a creates a press fit.

The line 63 of the adjusting element 46 extends in the axial direction of the adjusting element 46 into the joining area between the wedge sleeve 44 with the planetary bolt zen 42 and the planetary carrier 34. The wedge sleeve 44 and the planetary bolt 42 are in the end region facing the page 54 in the same way Scope formed with lines to during the joining process of the wedge sleeve 44 hydraulic fluid via the actuating element 46 in the joining areas between the wedge sleeve 44 and the Planet pin 42 and between the wedge sleeve 44 to initiate the planet carrier 34 can.

Fig. 6 shows a schematic partial representation of the planet carrier 34, the planet bolt 42 and the wedge sleeve 43. In addition to the outer circumference 57 or the outer diameter of the wedge sleeve 43 and the inner diameter 58 of the wedge sleeve 43, there is an inner diameter 66 of a bore 67 of the Planet carrier 34 and an outer diameter 68 of the planet pin 42 is specified. A maximum oversize in the area between the outer circumference 57 of the wedge sleeve 43 and the inner diameter 66 of the bore 67 of the planet carrier 34 is determined from the sum of the difference between the outer diameter 57 of the wedge sleeve 43 and the inner diameter 66 of the bore 67 and the Sum of the tolerance fields of the outer diameter 57 and the inner diameter 66.

In addition, the maximum internal oversize between the inner diameter 58 of the wedge sleeve 43 and the outer diameter 68 of the planetary pin 42 corresponds to the sum of the difference between the outer diameter 68 of the planetary pin 42 and the inner diameter 58 of the wedge sleeve 43 and the sum of the tolerance fields of the inner diameter 58 and the outer diameter 68.

Thus, the total maximum oversize results from the tolerance stack, which corresponds to the sum of the maximum outer oversize and the maximum inner oversize and has a significant influence on the joining process or the loosening process of the press fit between the planet carrier 34 and the planet pin 42 as well as the interposed wedge sleeve 43 has. This assumption applies to small cone angles in the area of the conical surfaces of the wedge sleeve 43 and the planetary pin 42. This means that if only the diameters of the components involved in the press fit are taken into account, the total scatter is equal to the sum of the four tolerances of the diameters 57, 58, 66 and 68 is.

In order to be able to produce or loosen the press fit between the planetary carrier 34 and the planetary pin 42 and the wedge sleeve 43 arranged between them to the desired extent, ie without causing irreversible damage in the area of the To cause the planet carrier 34, the planet pin 42 and the wedge sleeve 43, the procedure described in more detail below is proposed. The procedure is described in more detail below only on the basis of a joining process or during insertion of the wedge sleeve 43 between the planetary carrier 34 and the planetary pin 42, since the procedure is also carried out in the same way during a release process of a press fit

First, the planetary carrier 34, the planetary pin 42 and the wedge sleeve 43 are positioned in the device 40 in the manner shown in more detail in FIG. The wedge sleeve 43 is then inserted between the planet carrier 34 and the planet pin 42 by applying an axial actuating force Fa. The axial actuating force Fa is determined by means of a sensor of the device 40 during the joining process of the wedge sleeve 43 or during the production of the press fit. At the same time, as already explained in more detail above, hydraulic fluid or oil is introduced via a high-pressure hydraulic fluid injection device of the device 40 between the wedge sleeve 43 and the planet carrier 34 and between the wedge sleeve 43 and the tarpaulin tenbolt 42 under pressure. In addition, the pressure with which the hydraulic fluid is introduced is determined by means of at least one pressure measuring sensor of device 40 .

To avoid unacceptably high loads during the joining process in the area of the Pla designated carrier 34, the planet pin 42 and the wedge sleeve 43, d. H . To avoid plastic flow or chip formation, the pressure with which the hydraulic fluid is introduced is automatically varied when an axial actuating force Fa is greater than or equal to a predefined upper limit value until the axial actuating force is smaller than the predefined upper limit Limit.

The procedure is based on an adaptive control, which uses the profiles of the axial actuating force Fa, which are carried out in FIG. The discrete travel value S1 corresponds to a position of the wedge sleeve 43 in which the wedge sleeve 43 is in contact with one end face of the bore 67 of the planetary carrier 34 and in which there is still no overlap between the wedge sleeve 43 and the planetary carrier 34 or the planetary pin 42 . The further discrete adjustment path value S2 corresponds to an axial position of the wedge sleeve 43 in which the press fit between the planetary carrier 34, the planetary pin 42 and the wedge sleeve 43 is fully established.

The illustration according to FIG. 7 shows that the axial actuating force Fa to be used to produce the press fit increases progressively from the actuating travel value S1 in the direction of the further actuating travel value S2. The lower curve Fau of the axial actuating force Fa corresponds to a curve of the actuating force Fa, which is determined using a numerical model for a lower maximum overall oversize between the planet carrier 34, the planet bolt 42 and the wedge sleeve 43 and for lower coefficients of friction between these components as a middle course Farn or an upper course Fao of the axial adjusting force Fa. This means that the axial adjusting force Fa to be applied in each case to produce the press fit increases with increasing maximum overall oversize and with increasing coefficients of friction.

The numerical model is calibrated depending on empirically determined data. To calibrate the numerical model, a sufficient number of joining processes are carried out and the axial actuating forces to be applied are determined by measurement. In addition, the respectively corresponding pressure values with which the hydraulic fluid is introduced between the planetary carrier 34, the planetary pin 42 and the wedge sleeve 43 are determined by measurement and used to calibrate the numerical model. Furthermore, when specifying the process parameters of the joining process, the entire maximum and the entire minimum oversize are taken into account. In addition, the final dimensions of the components 34, 42 and 43 are taken into account so that the joining process can be carried out as soon as the process parameters have been determined as a function of the maximum permissible oversize. If the word-case scenario is present, the maximum total oversize is present in combination with other circumstances that increase the axial actuating force, which can be compensated for by the adaptive control described in more detail below, without having to stop the joining process or change the process parameters manually have to.

In addition, the adaptive control described in more detail below offers the possibility of expanding narrow manufacturing tolerances and thus improving manufacturing productivity and reducing manufacturing rejects. Normally, such a high level of variability is only possible by specifying different process parameters, which, however, is not necessary due to the proposed adaptive control.

In addition to calculating the curves Fau to Fao shown in FIG. 7, which are only three curves in a family of curves, the numerical model is also able to determine upper and lower limit values for individual curves in the family of curves in order to avoid damage to the Components 34, 42 and 43 to avoid.

During the joining process, the determined values of the axial setting force Fa are used to check whether the axial setting force Fa currently applied to the wedge sleeve 43 is less than an upper limit value.

The further description is based on the illustration according to FIG. 8 , which shows several curves of different process parameters of the device 40 according to FIG. 4 . Different curves of the axial actuating force Fa and the radial pressure p of the hydraulic fluid over the operating time t are shown in each case. A curve Fath corresponds to a theoretical curve of the axial positioning force Fa during the production of the press fit between the components 34, 42 and 43. Since the axial adjustment path S increases steadily over the operating time t, starting from the adjustment path value S1 in the direction of the adjustment path value S2, it also increases the theoretical curve Fath of the axial positioning force Fa to the extent shown. An upper theoretical curve Fatho is indicated above the theoretical curve Fath, which runs at least approximately parallel to the theoretical curve Fath of the axial actuating force Fa. In addition, a theoretical lower curve Fatu, which also runs parallel to the theoretical curve Fath, is shown, which represents a lower limit of the axial actuating force Fa. Furthermore, an actual curve Faactual of the axial actuating force Fa is given, which graphically reproduces the actuating force Fa actually applied to the wedge sleeve 43 .

At a point in time T 1 , an axial adjusting force Faactual (T 1 ) is applied to the wedge sleeve 43 , as a result of which the wedge sleeve 43 is pushed in between the planetary carrier 34 and the planetary pin 42 . As the axial adjustment path S of the wedge sleeve 43 increases, the actual curve Faactual of the axial actuating force Fa increases to the extent shown. The radial pressure p of the hydraulic fluid has a constant pressure level p(T1) from the point in time T1.

At a point in time T2, the actual curve Faist reaches the upper curve Fatho, which also represents a curve of an upper limit value of the axial actuating force Fa. Since the actual curve Faactual of the axial actuating force Fa exceeds the upper curve Fatho at time T2, the radial pressure p of the hydraulic fluid is ramped from time T2 to the extent shown to a time T3 to a pressure level p(T3). When the pressure level p(T3) is reached, the actual curve Faact of the axial actuating force Fa falls below the upper curve Fatho of the axial actuating force Fa, which is why the pressure p is left at the pressure level p(T3) from the point in time T3.

At a later point in time T4, the actual curve Faist of the axial actuating force again exceeds the upper curve Fatho, which is why the radial pressure p of the hydraulic fluid is increased in a ramped manner from point in time T4 to a point in time T5. At time T5, the radial pressure p has a pressure level p(T5) at which the actual curve Faist of the axial actuating force Fa falls below the upper curve Fatho again. For this reason, the radial pressure p is left at the pressure level p(T5) from the point in time T5.

In the event that the actual curve Faact falls below the lower curve Fathu, the radial pressure p is preferred to an extent that is not shown in detail reduced in a ramp shape until the actual curve Faist again runs between the lower curve Fathu and the upper curve Fatho of the axial actuating force Fa.

However, if the radial pressure p is not sufficient to reduce the axial actuating force Fa to the extent described above, a curve Faomax is stored in the adaptive control system, above which an axial actuating force Fa is applied to the wedge sleeve 43 undesired chip formation during the release position of the press fit. In the present case, the course Faomax has a constant value Famax from a point in time T6, above which plastic flow occurs in the area of wedge sleeve 43 and/or in the area of planet bolt 42 and/or in the area of planet carrier 34 if wedge sleeve 43 is subjected to greater axial forces than the Fmax value is applied. In the present case, the range of the axial setting force Fa in which chip formation is promoted is above the curve Faomax and below the value Famax of the axial setting force Fa.

During the joining process, on which the curves shown in FIG. 9 are based and which in turn starts at time T1, the actual curve Faist exceeds the upper curve Fatho at a time T7. When the upper curve Fatho is exceeded, the radial pressure p is again increased in a ramp-like manner from the point in time T7 up to a point in time T8. Since the pressure increase up to the time T8 does not bring about the desired reduction in the axial actuating force Fa and the actual course Faist at the time T8 exceeds another upper course Fathomax, the radial pressure p increases with a greater gradient in the direction of a maximum pressure value from the time T8 pmax that the radial pressure p reaches at a time T9. From the point in time T9, the radial pressure p is left constant at the maximum pressure value pmax. In the case considered here, the maximum pressure value pmax has the effect that the actual curve Faactual falls below the upper maximum curve Fathomax at a point in time T10.

This event triggers a ramp-shaped reduction in the radial pressure p starting from the maximum pressure value pmax. Since the actual curve Faist falls below the upper curve Fatho at a point in time T11, the radial pressure p is left constant at the pressure level p(T11) from the point in time T11 and the wedge sleeve 43 further inserted between the planetary carrier 34 and the planetary pin 42 until the press fit is finally established.

Reference character list

main axis of rotation

gas turbine engine

core

air intake

low-pressure compressor

high-pressure compressor

incinerator

high pressure turbine

bypass exhaust nozzle

low pressure turbine

core thruster

engine nacelle

bypass channel

thrust fan

support structure

shaft, connecting shaft

connecting shaft

Sun gear A Tooth profile of the sun gear

Gears, planetary gears

planet wheel

planet carrier

linkage

ring gear

contraption

pressing device

component, planet bolt

clamping element

actuator

actuator 47 cover element

48 housing area of the actuator

49, 50 housing-side stop

51 mother

52 increased diameter range of the control element

53, 54 side of planet carrier and bearing pin 55A to 56 B spacer

57 outer circumference of the clamping element 23

58 inner diameter of the clamping element 23

59, 60 side of the clamping element 23 61 conical outer contour of the bearing pin 62 line of the bearing pin

63 line of the actuator

64 line of the clamping element 23 66 inner diameter of the bore

67 planet carrier hole 34

68 Planetary Bolt Outer Diameter 42 111 Core Flow 122 Bypass Flow

A, B axial direction X axial flow direction

Fa axial positioning force

Fau, Fern, Fao course of the force

Faist Actual progression of the axial positioning force

Fath theoretical course of the axial force

Fatho upper course of the theoretical course of the axial force

Fathu Lower course of the theoretical course of the axial actuating force

Fathomax Maximum upper course of the theoretical course of the axial positioning force Faomax course of a maximum upper limit value of the axial actuating force

Famax maximum value of the axial positioning force

P radial pressure of the hydraulic fluid pmax maximum pressure value of the radial pressure of the hydraulic fluid

P(T1), p(T3), P(T5), p(T11 ) discrete pressure value T1 to T11 discrete time t operating time

Claims

patent claims

1. A method for producing or releasing a press fit between at least one first component (42) and at least one second component (34) and at least one wedge sleeve (43, 44) arranged between them, wherein hydraulic fluid is injected during the generation or release of the press fit Pressure (p) is introduced between an outer surface of the wedge sleeve (43, 44) and an inside of the second component (34) and/or between an inside of the wedge sleeve (43, 44) and an outside of the first component (42), wherein an axial positioning force (Fa) is determined during the manufacture or release of the interference fit, and wherein the pressure (p) with which the hydraulic fluid is introduced is greater than or equal to a predefined upper limit value ( Fatho) is automatically controlled and varied until the axial actuating force (Fa) is less than the predefined upper limit value (Fatho).

2. The method according to claim 1, characterized in that the joining process is ended when an axial actuating force (Fa) is determined to be less than a predefined lower limit value (Fathu) during the production of the press fit.

3. The method according to claim 1 or 2, characterized in that the joining process is ended if, during the production of the press fit, an axial actuating force (Fa) is greater than a further predefined upper limit value (Famax), which is greater than the upper limit (Fatho) of the actuating force and above which plastic deformations occur in the area of the components (34, 42) and/or the wedge sleeve (43, 44).

4. The method according to any one of claims 1 to 3, characterized in that the joining process is terminated when the pressure (p) exceeds an upper limit value (pmax) during the production of the press fit.

5. The method according to any one of claims 2 to 4, characterized in that the upper limit value (Fatho) and/or the lower limit value (Fathu) of the axial actuating force (Fa) as a function of an adjustment path (S) of the wedge sleeve (43, 44) compared to the Components (34, 42) or depending on a displacement path of one of the building parts compared to the other component and compared to the wedge sleeve varies.

6. The method according to any one of claims 2 to 5, characterized in that a course of the actuating force (Fau, Farn, Fao) as a function of an axial adjustment path (S) of the wedge sleeve (43, 44) relative to the components (34, 42) or is determined as a function of the displacement path of one of the components relative to the other component and relative to the wedge sleeve.

7. The method according to any one of claims 1 to 6, characterized in that the course of the actuating force (Fa) is determined by means of a numerical model which is calibrated as a function of empirically determined data.

8. The method according to any one of claims 4 to 7, characterized in that the pressure (p) of the hydraulic fluid is left at the pressure level of the upper limit value (pmax) for a defined period of time and it is checked during the period of time whether the actuating force (Fa) falls within the defined period of time to values below the upper limit value (Fatho), whereby the pressure (p) is reduced again if the test result is positive and the joining process is ended if the test result is negative.

9. The method according to any one of claims 4 to 8, characterized in that the pressure (p) falls below a further upper limit value of the pressure (p), which is smaller than the upper limit value (pmax) of the pressure, is kept constant.

10. The method according to any one of claims 1 to 9, characterized in that the first component (42) is a planetary pin on which a planetary gear (32) of a tarpaulin transmission (30) is mounted, and the second component (34) as a Planet carrier is formed from, wherein the planet pin (42) end in bores (67) of the tarpaulin tenträgers (34) is arranged and the at least one wedge sleeve (43, 44) for Fierstel development of the press fit between the planet pin (42) and the planet carrier ( 34) is pressed in and pushed out to loosen the press fit.

11. Device (40) for producing or releasing a press fit between at least one first component (42) and a second component (34) and at least one wedge sleeve (43, 44) arranged between the components (42, 34) with a pressing device (41 ) for applying an axial actuating force (Fa) to the structural parts (34, 42) and to the wedge sleeve (43,44), with at least one sensor for determining the axial actuating force (Fa), with a high-pressure hydraulic fluid injection device for introduction of hydraulic fluid under pressure (p) between an outer surface of the wedge sleeve (43, 44) and an inner side of the second component (34) and/or between an inner side of the wedge sleeve (43, 44) and an outer side of the first component (42 ), with at least one pressure measuring sensor for determining the pressure (p), with a control unit for carrying out the method according to any one of claims 1 to 10.

12. Control unit for producing or releasing a press fit between at least one first component (42) and at least one second component (34) and we least one wedge sleeve (43, 44) arranged between them, the control unit being designed in such a way that during the production or the loosening of the press fit, in each case hydraulic fluid under pressure (p) between an outer surface of the wedge sleeve (43, 44) and an inner side of the second component (34) and/or between an inner side of the wedge sleeve (43, 44) and an outer side of the first Component (42) is introduced, with an axial actuating force (Fa) being determined during the production or loosening of the press fit, and the pressure (p) with which the hydraulic fluid is introduced being greater when an axial actuating force (Fa) is present or equal to a predefined upper limit value (Fatho) is automatically varied until the axial actuating force (Fa) is smaller than the predefined upper limit value (Fatho).

13. Control device according to claim 12, characterized in that the process according to one of claims 1 to 11 is carried out on the control side.

14. Computer program product with program code means, which are stored on a computer-readable data carrier, in order to carry out all the steps of a method according to one of claims 1 to 11, if the computer program product is on a computer or on a corresponding computing unit, in particular a control unit according to claim 12 , is performed.