GB2511785A

GB2511785A - A support apparatus for supporting a device for expanding a sleeve in a bore

Info

Publication number: GB2511785A
Application number: GB201304470A
Authority: GB
Inventors: Lee Wagstaff; Matthew John Davies
Original assignee: Airbus Operations Ltd
Current assignee: Airbus Operations Ltd
Priority date: 2013-03-13
Filing date: 2013-03-13
Publication date: 2014-09-17
Also published as: GB201304470D0; GB2511785A8

Abstract

A support apparatus 1 is connected to a hand held puller device 3 for cold expanding a sleeve (41 fig. 4) in a bore (43 fig. 4) which may be formed in a surface of a composite aircraft wing structure. The support apparatus 1 may comprise four roller ball feet 15, a circular base 17 carrying a rotatable circular plate 19 upon which is mounted a column 21, along which a carriage 25 may slide in grooves 23. The carriage 25 may carry a lockable, slideable grooved arm 31 upon which is mounted a gimbal 33 for carrying the device 3. The support apparatus 1 is arranged to counter-balance the weight of the device 3 for example with a counter-weight 24, connected to a flexible member such as at least one chain 27 passing over a pulley 29. The support apparatus 1 is arranged such that device 3 is manoeuvrable to a user-determined position and is supported in the user-determined position, enabling the vertical position of the device 3 to be adjusted without the user needing to lift the full weight of the device. Once approximately aligned the support device may allow the puller device 3 to align itself with the bore (43 fig. 4) during actuation before it pulls a mandrel through the sleeve (41 fig. 4), allowing remote actuation of the device 3.

Description

SUPPORT APPARATUS FOR SUPPORTING A DEVICE FOR EXPANDING A

SLEEVE IN A BORE

Technical Field

S

The present invention relates to a support apparatus and mote particularly to a support apparatus for supporting a device for expanding a sleeve in a bore.

Background of the Invention

When fixing parts together with a bolt or other fastener that passes through a bore through the parts (particularly when the parts are made of differing materials) it is conunon to provide a sleeve, for example in the form of a bushing or a bearing arrangement, to line the bore within one or more of the parts. One method of securing the sleeve within the bore is to insert the sleeve in the bore and then cold expand the sleeve. Such a technique is utilised in the GromExTM system provided by "FTI" (Fatigue Technology, Inc of Seattle, USA).

In this technique, a sleeve received in a bore is expanded using a hydraulic puller device. The puller device exerts a hydraulic pulling force that pulls a mandrel through the sleeve, whilst the puller device reacts at least some of the pulling force by means of a nose cap on the device that butts against the surface of the part that defines the bore. A fastener may then be accommodated within the sleeve to fix the parts together.

During assembly of an aircraft wing, a wing skin is typically held in a jig whilst sleeves are fitted to bores in the skin as necessary. For small diameter bores, hand-held devices axe used to cold expand a sleeve into each bores.

However, for larger bores (for example to accommodate a sleeve of 25.1mm or 29.8mm inner diameter, with a 1mm wall thickness), a powerful device would be required to cold expand the sleeve. Sufficiently powerful devices are known (for example, the "Big Brute Puller" -Part No. 2720-008 from FTI, may be capable of providing sufficient pulling force to I it those sizes of sleeve), however, such powerful devices tend to be correspondingly heavy (for example the Big Brute Puller may weigh over 20kg). It is therefore not possible to fit sleeves in these larger bores using a hand-held device, especially if they are above chest-height and/or awkward to access, Where these larger bores are present, the sleeves therefore need to be pre-fitted using bespoke tooling in a separate jig.

Summary of the Invent ion

The present invention seeks to reduce or mitigate at least some of these problems.

According to a first aspect of the invention there is provided a support apparatus connected to a device for cold expanding a sleeve in a bore, the device being operable to exert a pulling force to pull a mandrel through the sleeve whilst reacting at least some of the pulling force against the surface defining the bore, the device being operable on the support apparatus from: a first position in which the device is connected to the mandrel and the mandrel is in only approximate alignment with the sleeve, to a second position in which the device abuts the surface defining the bore and the mandrel is in alignment with the sleeve, the support apparatus being arranged to support the device in the first position whilst also allowing movement from the first position to the second position, The support apparatus may be arranged such that the device may move from the first to the second position under the influence of the pulling force exerted by the device. Such a support apparatus may remove the need for the user to hold the device in position before, or when, actuating it. When the device is in the first position, the mandrel may be in only approximate alignment with the sleeve because, for example, it has not yet been pulled into a tight fit with the sleeve, The device may be operable to align the mandrel with the bore under the action of the pulling force. The device is preferably actuatable from a location remote from the device; the user can therefore be remote from the device during its actuation, thereby reducing any risk of injury that might otherwise occur if the device were to align whilst the user was holding it. It will be appreciated that the movement from the first position to the second position may be relatively small -for example the device may already be partially abutting the surface when it is in the first position, but more uniformly contact the surface when in the second position.

The support apparatus may be arranged to counter-balance the weight of the device, thereby enabling the vertical position of the device to be adjusted without the user needing to lift the full weight of the device. The support apparatus may therefore enable a user to more easily manoeuvre a heavy device into the required position even it that position is above chest-height.

In principle, the support apparatus may be arranqed in & nunther of ways to counter-balance the weight of the device.

The support apparatus may comprise a hydraulic counter-balancing system. The support apparatus may comprise a pneumatic counter-balancing system. The support apparatus may comprise an electric counter-balancing system. More preferably however, the support apparatus comprises a mechanical counter-balance system. The counter balance system may comprise a counter-weight arranged to counter-balance the weIght of the device, Such an arrangement has been found to be beneficial in terms of simplicity of construction, safety and ease of maintenance. Furthermore, such an arrangement does not require the support apparatus to be connected to an external supply (for example a source of fluid or electrical power) for operation of the counter-balance.

The support apparatus may be arranged to counter'-balance at least 50%, more preferably at least 80%, and more preferably at least 90% of the weight of the device. The support apparatus may be arranged to counter-balance substantially the full weight of the device. Such an arrangement reduces the effective weight of the device to substantially zero which enables the user to more easily lift the device and also enables the support apparatus to more easily support the device in a fixed vertical position once the user is no longer applying a lifting force.

The first position is preferably a user-determined position. The device may be manually manoeuvrable to the first position (i.e. the user may directly push, pull, rotate or otherwise manoeuvre the device into the first position as if it were a hand-held device). This enables the device to be easily and/or quickly re-positioned (for example when fitting sleeves to a series of bores) -Furthermore, the present invention is especially beneficial when manually repositioning since it is the user that is saved from manually lifting the full weight of the device.

The support apparatus may be arranged such that the device is manoeuvrable in at least the vertical directions The support apparatus may be arranged such that the device is rotatable about at least two, and irtore preferably three, orthogonal axes of rotation. The support apparatus may be arranged such that the device translatable in at least two, and preferably three, orthogonal directions. The translation may be effected by a rotation about an axis offs'&t from the device. The support apparatus may be arranged such that the device has a plurality, and more preferably a multiplicity, of degrees of freedom. The support apparatus may be arranged S such that the device has six degrees of freedom. Such an arrangement is especially beneficial because the device can then be nianoeuvred into arty position in space (within the range of movement permitted by the support apparatus}. This enables the device to be used in a wide variety of scenarios.

The support apparatus is arranged to support the device.

For example, the support apparatus is preferably arranged to support the device in equilibrium once an external force (such as that exerted by the user to manoeuvre the device) is removed.

The device is operable to exert a pulling force to cold expand the sleeve. The pulling force may be effected by hydraulics. The device may be operable to pull a mandrel through the sleeve. The device is arranged to exert the pulling force whilst reacting at least some of that pulling force against the surface defining the bore. The device may be operable to exert at least 5kN pulling force, and more preferably at least SkN pulling force. The device may be operable to exert over 10kM pulling force. The weight of the device may be more than 10kg, and may be 20kg or more. The devIce may be puller device by FTI" (Fatigue Technology, Inc of Seattle, USA), such as a "Big Brute" Puller -Part No. 2720-*008, or a "Forcemate7 Super Brute". The sleeve may be fitted as part of FTI's GromEx?N system.

The device may be for cold expanding a sleeve in a bore of an aircraft part (i.e. plastically deforming the sleeve under an expansion force). The device may be for cold expanding a sleeve of up to 10mm, more preferably up to 25mm and yet more preferably up to 30mm inner diameter. The device may be for cold expanding a sleeve of up to 34mm inner diameter. The sleeve may be titanium. The sleeve may be steel. The sleeve may be aluminium. The sleeve may have a wall thickness of at least 1mm. The bore for receiving the sleeve may be more than 10mm, more preferably up to 25mm and yet more preferably up to 3orran diameter.

In embodiments comprising a counter-weight, the counter-weight and the device may be located on opposing sides of the support apparatus. The counter-weight and the device may be located either side of a pulley on the support apparatus. The counter-weight and the device may be coupled by a flexible member, such as a chain, passing over the pulley. Movement of the device in a vertical direction may move the counter-weight in the opposite vertical direction. The counter-weight is preferably substantially the same weight as the device, but in principle it could be any weight that has the effect of reducing the effective weight of the device.

According to another aspect of the invention there is provided a support apparatus for use as the support apparatus in the first aspect. of the invention.

According to yet another aspect of the invention there is provided a method of operating a device for cold expanding a sleeve in a bore, the device being operable to exert a pulling force to pull a mandrel through the sleeve whilst reacting at least some of the pulling force against the surface defining the bore, the method comprising the steps of: supporting the device in a first position using a support apparatus; and moving the device from the first position to a second position in which it abuts the surface defining the bore and the mandrel is in alignment with the sleeve. The method may comprise the step of connecting the device to the mandrel and approximately aligning the mandrel with the sleeve. The device may be connected to the mandrel when it is in the first position. The step of moving the device to the second position may be effected by actuating the device to exert a pulling force on the mandrel, the support apparatus being S arranged such that, the device is moveable under the pulling force, to the second position. In the second position, the device is preferably supported by the support apparatus.

The bore may he in an aircraft part, such as a wing skin.

The sleeve may be for receiving a fastener to hold an engine pylon. The method may comprise the step of cold expanding the sleeve in the bore using the device.

The method may comprise the step of manoeuvring the device above elbow-height. The method may comprise the step of manoeuvring the device above shoulder-height. The user-determined position may be adjacent to a wing skin.

It will be appreciated that any features described with reference to one aspect of the invention are equally applicable to any other aspect of the invention, and vice versa. For example, features described with reference to the apparatus of the invention may be equally applicable to the method of the invention.

Description of the Drawings

Various embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings of which: Figure 1 is a schematic of a known device for cold expanding a sleeve in a bore; Figure 2 is a perspective view of a support apparatus and a device for cold expanding a sleeve according to a first embodiment of the invention; Figures 3a and 3b are, respectively, side and plan views of the support apparatus and a device in Figure 2; and Figure 4 is a plan view of a bore with a sleeve fitted.

Detailed Description

Hand-held hydraulic puller devices for cold expanding a sleeve in a bore are known4 ror example, such devices are available from Fatigue Technology, Inc of 401 Andover Park East, Seattle, USA (FTI). These devices are capable of exerting a pulling force that pulls a mandrel of increasing diameter through the sleeve, thus expanding the sleeve, to form an interference fit for the sleeve in a bore. This cold-worked sleeve system is provided by FTI under the trade mark "GromEx".

An example of a hydraulic puller device is shown schematically in Figure 1, The device 103 comprises a hydraulically actuated piston 105 (shown in dotted line in tigure 1) received in a barrel 107. The barrel 107 is coupled to a cylinder 111, and the joint between the barrel and cylinder is surrounded by a housing 113. Hydraulics are attached to the cylinder via pipes 104 such that the application of hydraulic pressure actuates the extension and retraction of the piston 105. The application of the hydraulic pressure is effected by a user actuating a trigger 106. In Figure 1. the piston 105 is shown in its extended position, and when retracted, it moves further down into the barrel 107.

A known method of fitting a sleeve into a bore comprises the following steps: Firstly, a device 103 is held by a user and a mandrel shaft is attached (typically via a threaded adapter) onto the end of the piston 105. A nose cap 112 is then passed over the mandrel shaft and screwed onto the end of the barrel 107. The sleeve is then inserted into the bore..

The sleeve is of smaller diameter to the bore but typically has a flange at one end to prevent it falling through the bore. Next, the user inserts the mandrel shaft thzough the non-flanged end of the sleeve such that it protrudes from the opposing flanged end of the sleeve and out of the bore. A mandrel head (of greater diameter than the mandrel shaft and the sleeve) is then screwed onto this end of the shaft, The puller device 103 is then held such that the nose cap 112 on the end of the barrel 107 abuts the surface defining the bore.

In this position the device is actuated such that the piston is retracted? under hydraulic pressure, into the barrel.

The mandrel (i.e. the mandrel shaft with the head attached) is thereby pulled through the sleeve, forcing It to cold expand into the bore. By virtue of the nose cap 112 abutting the surface defining the bore, the pulling force from the device is reacted against that surface. Once the mandrel has been pulled all the way through the bore, the sleeve has been expanded such that it forms a tight interference fit in the bore. The mandrel head is then removed from the mandrel shaft such that the process can be repeated on the next sleeve.

Such a method is currently used to fit sleeves to relatively small diameter bores. It is desirable to be able to fit larger sleeves to larger diameter bores, but that would require a more powerful devIce, such as the "Big Brute Puller" -Part No. 2720-008 from rn. However, such a device tends to be too heavy to be able to be used above chest-height and may be difficult to manoeuvre to access awkwardly located bores.

For large bores in an aircraft component, such as a wing, it has therefore been necessary to pre-fit such large sleeves using bespoke tooling and a separate jig.

Figures 2, 3a and 3b show a support apparatus 1 according to a first embodiment of the invention, The support apparatus

-

1 holds a "Big Brute' Puller device 3 which is sufficiently high-capacity for cold working a stainless steel sleeve of at least 25.1mm inner diameter, and 1mm wall thickness. The layout of the structure of the device 3 is largely identical to that described with reference to Figure 1, and where appropriate, corresponding reference numerals have been used to indicate corresponding features, but with the omission of the 1' or 10' prefix as necessary.

The support apparatus 3. of Figures 2-3b is being used to fit the 25.1 mm diameter sleeve 41 into a bore 43 in a surface -see Figure 4 -of a composite wing structure (not shown).

This sleeve 41 is for receiving a size 16 (1 inch/25.4mm diameter) fastener (not shown) for attaching a pylon (not shown) to the wing structure, whilst also providing a means of enhancing lightning strike protection in the wing.

As will be apparent from the description below, the support apparatus 1 is especially useful when the wing is orientated with the wing chord running approximately horizontally such that the axis of the bore runs approximately vertically. This is because the bores in such an arrangement are not only awkward to access, but the user also needs to lift a puller device well above chest height in order to fit the mandrel shaft through the sleeve and bring the nose cap 12 of the barrel 7 close to the surface 45 of the wing.

The structure of the support apparatus 1 of the first embodiment will now be described in more detail with reference to Figures 2 -3b The support apparatus 1 comprises four roller-ball feet attached to a circular base plate 17. The roller-ball feet 15 are operable between an unlocked position in which they freely rotate enabling the support apparatus 1 to be moved in any direction, and a locked state in which their rotation is prevented. Roller-ball feet 15 have been found to be -11 -preferable to coasters because coasters can jam it facing away from the direction in which the support Is being urged to travel, and could cause the support apparatus to topple.

Adjacent the upper plate 19 is a tray 22 which may be used for holding various items.

Co-axial to, and directly on top of, the circular base plate 17 is a second circular plate 19, which is rotatable relative to the lower base plate 17 about a vertical axis 18.

A column 23. vertically extends from the second circular base plate 13. On one face of the column there is attached a strip of material into which four parallel, vertically extending, grooves 23 have been machined. A carriage 25 is slideably received in the grooves such that it can be manoeuvred vertically in a direction V (discussed in more detail below).

The carriage 25 holds an arm 31, also formed from the grooved material, in a horizontal orientation. The arm 31 is releasably held such that it can be locked in position by a locking mechanism (not shown), but the locking mechanism can also be released to enable the arm 31 to be moved across the width of the carriage 25 in a horizontal direction H. In the first embodiment of the invention, the carriage 25 is connected to two chains 27 which pass over two corresponding pulleys 29 mounted on the top of the vertical column 21, At their other end, the chains 27 are connected to a counter-weight 24 (visible in dotted lines in Figure 3b).

The counter-weight 24 is approximately the same weight as the device 3 and is arranged to counter-balance the weight of the device 3. By virtue of being connected by the chains 27 over the pulleys 29, the carriage 25 and the counter-weight 24 always move in opposing vertical directions.

A gimbal 33 is mounted on one end of the horizontal arm 31. The gimbal 33 comprises a CT-shaped bracket, the arms of which hold the device 3 such that it is rotatable about an axis 37 (riot visible in Figure 3a) passing between the arms, by +-20 degrees about a centre point. The gimbal 33 is also rotatably mounted on the end of the horizontal arm 31 about S another axis 39, orthogonal to the axis 37 between the arms of the gimbal 1, and extending along the length of the arm 31.

The gimbal 33 is also rotatably mounted about this axis by 4-degrees about a centre point.

The device is thus moveable about three orthogonal axes of rotation 18, 37 and 39. The bearings (not shown) that support the axes of rotation 18, 37, 39 on the support apparatus 1 all offer a moderate resistance to rotation such that the device 3 can be manually rotated by a user, but the device tends to remain in its position and orientation once the user removes any manoeuvring force they have applied to position the device.

Since the device 3 is rotatable about two axes of rotation 37 and 39 passing through the device, and one axis 18 off-set from the device, and is also translatable in orthogonal vertical V and horizontal H directions, the support apparatus 1 is arranged such that the device 3 has six degrees of freedom. By the user manually manoeuvring the device 3 on the support apparatus 1, the device 3 can thus be positioned at any point in space (within the ranges provided by the support apparatus 1). Furthermore, by virtue of the resistance in the axes of rotation 37, 39 and 18, the resistance in the pulleys 29, and the locking of the horizontal arm 31, the support apparatus 1 is arranged to support that device 3 in equilibrium once the manual inanoeuvring force has been removed.

To fit a sleeve 41 into a bore 43 in an aircraft structure, the user conducts several of the steps described above with reference to Figure 1, namely: the sleeve 41 is -13 -first inserted into the bore; the Big Brute Puller device 3 is manoeuvred by the user into proximity to the sleeve and the mandrel shaft (not shown) attached to the end of the piston S is inserted through the sleeve. The mandrel head is then S attached to the mandrel shaft from the other side of the sleeve In contrast to the steps described with reference to Figure 1, in the first embodiment of the invention the user does not need to lift or hold the weight of the device 3 when it is being manoeuvred into proximity to the sleeve, nor does the user need to abut the nose cap of the barrel against the surface of the wing. These improvements are facilitated by the support apparatus 1 as explained below: Firstly, the carriage 25, and thus the device 3, is vertically moveable in a direction V up the column. The carriage 25 is shown part way up the column 21 in Figure 2, but at its maximum height in Figures 3a and 3b. By providing the counter-weight 24 to counter-balance the weight of the device 3, the user is able to rtanoeuvre the device 3 In the vertical direction V, without needing to lift/hold its full weight. In the first embodiment of the invention, the bearings (not shown) associated with the pulleys 29 offer a moderate resistance to rotation, such that the device remains in its vertical position once any lifting/pushing force exerted by a user is removed, but also such that the resistance can be overcome relatively easily by the user as and when they reapply that, force, The support apparatus 1 of the first embodiment of the invention therefore enables a heavy devIce 3, such as the Big Brute Puller, to be more easIly manoeuvred enabling it to be used, for example, under an aircraft wing at above chest-height.

Secondly, by virtue of the support apparatus being arranged such that the device has six degrees of freedom, there is no need for the user to fully abut the nose cap 12 of -14 -the barrel 7 against the surface 45 of the wing before actuating the device 3. More specifically, the user may leave the device with the mandrel only approximately aligned with the bore 43 and/or not in full contact with the surface 45.

S The support apparatus 1 supports the device in this position such that it does not move once the user no longer touching it. However, once the device 3 is actuated, the actuation force pulls it. into alignment and against the surface of the wing before then pulling the mandrel through the sleeve 41 and bore 43. By providing the support apparatus in accordance with the first embodiment of the invention, the user can be remote from the device during its actuation, thereby reducing any risk of injury that might otherwise occur if the device 3 were to align whilst the user is holding it in position.

Accordingly, in the first embodiment of the invention, the trigger (not shown) for actuating the hydraulics (not shown) is remote from the device 3 and is instead provided on a separate handle coupled to the hydraulic fluid lines remote from the support.

Whilst the present invention has been described and illustrated with reference to a particular embodiment, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein. For example, the device may be any high capacity device for cold-expanding the sleeve, and is not necessarily the "Sig Brute Puller". The sleeve may be fitted into a bore in another aircraft structure, such as the land gear. The mandrel need not necessarily comprise a separate shaft and head (for example it may be tapered and inserted from the opposing side of the sleeve before attachment to the piston) Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such -15 -equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. rt will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. -16

Claims

Claims 1. A support. apparatus connected to a device for cold expanding a sleeve in a bore, the device being operable to exert a pulling force to pull a mandrel through the sleeve whilst reacting at least some of the pulling force against the surface defining the bore, the device being operable on the support apparatus from: a first position in which the device is connected to the mandrel and the mandrel is in only approximate alignment with the sleeve, to a second position in which the device abuts the surface defining the bore and the mandrel is in alignment with the sleeve, the support apparatus being arranged to support the device in the first position whilst also allowing movement from the first position to the second position.
2. A support apparatus and a device according to claim 1, wherein the support apparatus is arranged such that the device is moveable from the first to the second position under the influence of the pulling force exerted by the device.
3. A support apparatus and a device according to claim 1 or claim 2, whereIn the device is actuatable from a location remote from the device.
4. A support apparatus and a device according to any preceding claim, wherein the device is manually manoeuvrable to the first position.
5. A support apparatus and a device according to any preceding claim, wherein the support apparatus is arranged such that the device has a multiplicity of degrees of freedom. -17
6. A support apparatus and a device according to claim 5, wherein the support apparatus is arranged such that the device has six degrees of freedom.
7. A support apparatus and a device according to any preceding claim, wherein the device is for cold expanding a sleeve in a bore of an aircraft component.
8. A support apparatus and a device according to claim 7, wherein the device is for cold expanding a sleeve of at least 25mm inner diameter.
9. A method of operating a device for cold expanding a sleeve in a bore, the device being operable to exert a pulling force to pull a mandrel through the sleeve whilst reacting at least some of the pulling force against the surface defining the bore, the method comprising the steps of: supporting the device in a first position using a support apparatus; and moving the device from the first position to a second position in which it abuts the surface defining the bore and the mandrel is in alignment with the sleeve.
10.. The method according to claim 9, wherein the step of moving the device to the second position is effected by actuating the device to exert a pulling force on the mandrel, the support apparatus beIng arranged such that, the device is moveable under the pulling force, to the second position.
11. A method of operating a device according to claim 9 or 10, further comprising the step of cold expanding the sleeve in the bore using the device.
12. A method of operating a device according to any of claims 9 to 11, wherein the bore is in an aircraft component.
13. A method of operating a device according to any of claims 9 to 12, wherein the method comprises the step of manoeuvring the device above elbow-height.
14. A support apparatus f or use as the support apparatus of claims 1 to 8.
15. A support apparatus and method of operating a device for cold expanding a sleeve in a bore as herein described with reference to the Figures.