WO2018126297A1

WO2018126297A1 - A segmented nut and a device for use in releasing nut type fasteners

Info

Publication number: WO2018126297A1
Application number: PCT/AU2018/050001
Authority: WO
Inventors: Brian Eric BRADSHAW; Tom Peter BASKOVICH; Sam William TURNBULL
Original assignee: Segnut Pty Ltd
Priority date: 2017-01-03
Filing date: 2018-01-02
Publication date: 2018-07-12

Abstract

A device or tool 10, 200, 300, 400, 500, 600 has first part 14, 204, 304, 404, 504, 604 in a second part 12, 202, 302, 402, 502, 602 for relative rotation and reaction torque to release a segmented nut 100, 700, 800 not needing a reaction arm. The first part can have articulated engagement portions 206. The device or tool can be driven by or be part of a drive tool e.g. electric, pneumatic or hydraulic powered or manual driver. The nut segments 610, 710, 810 (610A-610C, 710A- 710C and 810A-810C) can be flanged 714, 814 (714A-714C, 814A-814C) providing an integral washer preferably having drive faces 718AA-718CB, 818AA- 818CB. The second part can have drive portions 717 to apply torque to the flange(s) and spaces 719 allowing radial outward movement of the flange portions and associated segments.

Description

A SEGMENTED NUT AND A DEVICE FOR USE IN RELEASING NUT TYPE FASTENERS

FIELD OF THE INVENTION

[0001 ] The present invention finds application relating to segmented nuts.

[0002] One or more non-limiting forms of the present invention provides a device/tool for use in at least releasing nut type fasteners, such as segmented nut type fasteners.

[0003] One or more other non-limiting forms of the present invention provides one or more improvements to segmented nut type fasteners.

BACKGROUND TO THE INVENTION

[0004] Manual tools, such as spanners, wrenches and sockets, are often used to install and remove nuts. There are leverage and space limitations when using manual tools. In order to apply sufficient torque to tighten or release a nut, the lever arm distance may need to be greater than the space available for one person to apply sufficient torque. A shorter lever arm distance may result in the nut not being sufficiently tightened or may not allow sufficient release torque to be applied. Where a nut has a high release or tightening torque, the manual tool user needs to brace their self to transfer a reaction torque in response to the torque applied to the nut. The user may not be able to sufficiently brace their self or may only then have one hand free to use the tool and not be able to use the tool safely or adeptly. Consequently, power tools are often employed in such situations.

[0005] Using power tools to install and remove nuts avoids the need for laborious use of manually operated tools, such as spanners, wrenches and sockets. Using power tools is often a first choice in removing nuts as this may in some cases avoid the need to cut the nut from the bolt using oxy-acetylene cutting equipment.

[0006] However, use of power tools can generate a reaction torque in an opposite direction to the torque applied by the power tool. If the nut does not rotate when the power tool applies rotational drive to the nut, the power tool itself may try to rotate in the opposite direction to the applied rotation, risking injury to the operator.

[0007] The power tool often has a handle and/or other projection that can violently and quickly counter-rotate during powered release of the nut, ripping the power tool out of the operator's grasp, risking hand or other injury.

[0008] Also, counter-rotation of the power tool may trap or crush the operator's hand in a 'pinch-point' between the power tool and a work- piece/equipment adjacent the nut/power tool, such as in restricted access areas.

[0009] Other forms of power tool may use high frequency rotational impacts to tighten or loosen nut fasteners. Whilst the counter torque in such tools is limited due to the high frequency application of the torque, the operator may suffer from a number of negative consequences including upper arm Cumulative Trauma Disorders which is a form of repetitive strain injury. There is a need to reduce injuries and trauma to operators of nut removal equipment.

[0010] Attempts have been made to prevent such counter-rotation of the power tool due to reaction torque when releasing nut type fasteners.

[001 1 ] Reaction fixtures have been used whereby an arm (a "reaction arm") is attached to the power tool in a fixed position and extends to engage against the fixed body of the equipment to which the nut type fastener is attached. Reaction torque of the power tool is transferred through the reaction arm to the body of the equipment and prevents the power tool counter-rotating. However, there is still a risk that the operator may get injured by a hand or finger getting trapped between the reaction arm and the body of the equipment, particularly if there is limited access/vision and/or the power tool/reaction arm needs repositioning.

[0012] An alternative attempt to reduce or remove the risks associated with reaction torque when trying to release nut type fasteners is provided by a washer incorporating a profiled circumference somewhat like a thin sprocket or toothed gear. The washer, which is of a larger diameter then its associated nut, goes between the regular (hexagonal) nut and the work-piece and is held in that position through the friction forces between the nut and the working face of the equipment to which it is attached and is ultimately reacted back to the ground upon which the equipment is placed. A double layered socket mounted on a driven end of the power tool slides over the nut to be released. The outer layer of the socket engages with the shaped profile of the teeth and valleys on the washer's circumference. The inner layer of the socket engages with the nut. Release torque is applied by the inner layer whilst the reaction torque is reacted through engagement of the outer layer with the washer.

[0013] Clearly, an additional specialised component is required in needing the profiled washer. Also, because the washer is relatively thin (as washers are by their very nature and purpose to interface and transfer force between the working face of the nut and the work-piece) the outer layer of the socket may not sufficiently engage with the washer in certain situations of limited access or where the outer profile of the washer has become damaged through impact and/or corrosion through use, such as fasteners attaching wear plates/ground engaging tools to buckets of heavy digging vehicles.

[0014] Furthermore, in order to be able to create a reaction torque, the washer must be prevented from rotating, which will only be the case whilst there is sufficient tension on the nut to create a frictional resistance on the washer. As the nut achieves a degree of loosening, the friction between the nut and the washer will be lost, and therefore the washer can no longer sustain the reaction torque. This can occur before the nut is fully released and whilst a substantial removal torque is still required to remove the nut (e.g. due to substantial or partial seizure of the nut on the bolt thread or other causes of a prevailing torque).

Another form of nut removal would therefore be needed.

[0015] In summary, there is a requirement for a minimum state of tension to be applied by the nut to the reaction washer in order for a reaction torque to be sustained. In effect the counter acting torque is still being reacted to the workpiece to which the nut is attached (i.e. the reaction washer passes the reaction torque to the surface of the workpiece to which it is in contact with).

[0016] The present invention proposes an alternative approach to alleviating one or more problems associated with reaction torque.

SUMMARY OF THE INVENTION

[0017] In one aspect, the present invention provides a system or device for use in releasing a segmented nut, the device including a first portion to engage with at least one segment of an inner nut of the segmented nut, and a second portion to engage with an outer sleeve of the segmented nut, the device allowing relative rotation of the first portion and second portion for release of the

segmented nut.

[0018] A further aspect of the present invention provides a system or device for releasing a segmented nut, the system or device including a first portion to engage with a nut first part, and a second portion to engage with a nut second part, the first portion and the second portion arranged to counteract torque with respect to one another.

[0019] For example, the system or device may include the first portion for applying the torque to a first part of a multi-part (segmented) nut and the second portion for applying the counter (reaction) torque to a second part of the multi-part (segmented) nut, the system or device including a first engagement portion for engagement with the first part of the multi-part nut and a second engagement portion for engagement with the second part of the multi-part nut, wherein rotation of the first part relative to the second part releases the multi-part nut.

[0020] Preferably, substantially all torque applied to the nut, including the counter (reaction) torque, is/are applied by the tool without torque transferred to or from a structure to which the nut is fastened.

[0021 ] Preferably, the multi-part nut is a segmented nut having at least two segments forming an inner thread of the nut, and an outer sleeve or collar extending around at least a portion of the segments.

[0022] The multi-part nut may include a flange projecting transversely with respect to hole through the segments. The flange may be coaxial with the hole through the nut formed by the segments. For example, the flange may extend laterally/sideways/normal with respect to a central axis through the hole through an inner nut formed by the segments. It will be appreciated that the flange may preferably extend beyond a sleeve around the segments.

[0023] The flange preferably provides a contact surface of the nut for contact with a workpiece, spacer or washer. The contact surface may include an annular bearing surface which projects away from, or provides a step from an edge of the flange, and/or that is inset from an edge of the flange.

[0024] An edge profile at a lower portion of one or more of the segments may be arranged and configured to engage with the device for releasing the nut. The edge profile may include a multi-faceted surface in plan view. The edge profile may be hexagonal in plan view with faces/sides of the hexagon formed by the flange of the segments. [0025] It will be appreciated that the segmented nut preferably includes at least two inner nut segments providing a nut thread to engage with a thread of a threaded shaft, and an outer sleeve which engages, in a first position, to retain the at least two inner nut segments in engagement with the thread of the shaft, and, when rotated to a second position relative to the at least two inner nut segments, allows release of the at least two inner nut segments from the engagement with the thread of the shaft.

[0026] Advantageously, the device engages with the inner nut and with the outer sleeve of the segmented nut, enabling rotation of the outer sleeve of the segmented nut relative to the inner nut for release of the segmented nut.

[0027] Rotational release torque applied to the outer sleeve or inner nut of the segmented nut is reacted through engagement with the respective inner nut or outer sleeve of that segmented nut, and does not require additional components, such as a specialised washer with which to engage, and does not require a reaction arm and associated external body to react against.

[0028] It will be appreciated that the segmented nut does not need to be in tension in order for counteracting torques to be reacted. The reaction torque is not being transmitted to the workpiece (and ultimately to the ground) to which the nut is attached.

[0029] For example, in the prior art, an arrangement using a reaction washer between the nut and workpiece could not be used on a piece of equipment that was not connected solidly to the ground as otherwise the whole workpiece could rotate, negating the benefits of a reaction washer.

[0030] The device may preferably be power driven, such as by pneumatically or hydraulically operated drive means or electric/battery motor powered drive means. For example, the device may be adapted to releasably engage with a drive portion of the driver or may include an integral drive means. [0031 ] The device may include a drive input portion arranged to releasably engage with a drive output portion of a power operated driver.

[0032] Beneficially, by having no pinch-point that can otherwise occur with reaction arms, and by avoiding the need to find a stable and suitable spaced reaction point, one or more forms of the present invention improves safety for operators compared with pinch-point risk through use of such reaction arms.

[0033] Furthermore, when used with a segmented nuts, such as those developed by the present applicant and disclosed in patent applications including international (PCT) patent application PCT/AU2015/050803 published as WO 2016/094953 and international patent PCT/AU2017/051057, the contents of each are herein incorporated by reference in their entirety, the energy required to release such segmented nuts is significantly lower than required to release comparative conventional solid (one piece) nuts. This allows the opportunity to use battery powered tools for nut removal as there is a significant increase in the number of nuts that can now be released due to the lower energy draw to release each segmented nut.

[0034] A combination of a tool, system or device according to one or more embodiments of the present invention and one or more segmented nuts developed by the present applicant or third party segmented nuts compatible with the present invention provides a substantial benefit to a user through one or more of speed of use, efficiency and safety.

[0035] In addition, one or more forms of the present invention beneficially provides coaxially aligned inner and second portions to engage with the respective inner nut and outer sleeve, which helps where a torque reaction arm would be hard to fit due to space/access restrictions.

[0036] Preferably, the device includes a clearance between a part of the first portion and a part of the second portion. For example, the first portion may include multiple engagement portions arranged to move radially relative to a central axis (such as a central axis of the device, of the second portion or of the segmented nut to be released) to engage/disengage with respective segments on the inner nut of the segmented nut

[0037] Preferably the engagement portions include at least one projection arranged and configured to engage with a corresponding at least one receiver portion provided on the respective segment(s) of the inner nut.

[0038] For example, the engagement portions of the device to engage with the inner nut segments may include castellation(s) to engage, in use, with respective recess(es) or castellation(s) of the segments.

[0039] The segmented nut may include engagement portions on the inner nut e.g. may be castellated or have an arrangement of projections and recesses on upper and/or side surface(s) of the inner nut to which a torque may be applied to release the segmented nut.

[0040] Preferably the first portion is power driven to rotate relative to the second portion.

[0041 ] However, it will be appreciated that the second portion may be driven to rotate relative to the first portion.

[0042] Alternatively, the first portion and second portion may rotate in opposite directions relative to one another. One of the first and second portions may be driven to rotate and the other either driven or stationary. The first and second portions may be selectively locked to be driven to rotate together in the same direction of rotation.

[0043] The first portion may include a drive portion which receives rotational drive from a drive output of a powered drive means. For example, the first portion may include an aperture to receive a drive member of a drive means. The aperture may be a square, hexagonal, star drive aperture to receive a

correspondingly shaped drive means. The drive aperture may receive a socket drive to drive the first portion.

[0044] Preferably the first portion may engage corners of the inner nut. Such engagement can be sufficient to transmit torque to the inner nut. In addition, after rotating back, the segments of the inner nut may be allowed to expand and/or move radially outwards, whilst still within the first portion.

[0045] Preferably, the second portion of the device includes an inside surface which contacts the engagement portions of the first portion such that, during relative rotation of the engagement portions and inside surface, contact portions of the internal surface cause the engagement portions to move radially.

[0046] Preferably the inside surface includes a surface profile that transitions periodically in radial distance from a central axis corresponding to positions of the engagement portions. The inside surface can provide a driving contact surface to push the engagement portions radially as the internal surface rotates relative to the engagement portions.

[0047] The engagement portions can be moved radially in and out with respect to a central axis, and are preferably forced inwards by a 'cam' profile of the internal surface.

[0048] One or more biasing means may return each respective engagement portion outwardly as the respective cam profile of the internal surface transitions to an Off-cam' portion more radially distant form the central axis than the cam profile.

[0049] An alternative form of the present invention includes a segmented nut including an inner nut including at least two segments, each segment including part of an internal thread for engagement with a thread of a shaft, and an outer sleeve for retaining the segments together in one rotational orientation of the outer sleeve and allowing separation of the segments in another rotational orientation of the outer sleeve, the inner nut including at least one receiver for engagement with a device for releasing the segmented nut.

[0050] The segmented nut may have the inner nut including at least one receiver at an upper portion thereof for engagement with a device for releasing the segmented nut. Alternatively, or in addition, the inner nut may include at least one said receiver at a lower portion thereof for engagement with a device for releasing the segmented nut.

[0051 ] The lower portion may include a flange projecting transversely with respect to hole through the inner nut formed by the segments. The flange may be coaxial with the hole through the inner nut. For example, the flange may extend laterally/sideways/normal with respect to a central axis through the hole through the inner nut. It will be appreciated that the flange may preferably extend beyond the sleeve.

[0052] The flange preferably provides a contact surface of the segmented nut for contact with a workpiece, spacer or washer. The contact surface may include an annular bearing surface which projects away from, or provides a step from an edge of the flange, and/or that is inset from an edge of the flange.

[0053] The receiver when provided at the lower portion of the inner nut may include an edge profile arranged and configured to engage with the device for releasing the segmented nut. The edge profile may include a multi-faceted surface in plan view. The edge profile may be hexagonal in plan view with faces/sides of the hexagon formed by the flange of the segments of the inner nut. [0054] The multi-part nut or segmented nut may include at least one outer chamfer surface extending between the respective bearing surface and an outer edge of the respective flange portion of each segment.

[0055] Preferably, the inner chamfer surface(s) and/or the outer chamfer surface(s) may have an angle of between 10° and 60°, more preferably between 20° and 45°, and even more preferably around 30°, relative to a plane of the bearing surface.

[0056] The at least one receiver may include castellation at an upper portion of the inner nut arranged to receive at least one engagement portion of the device.

[0057] A further alternative aspect of the present invention provides a device for use in releasing a segmented nut in engagement with a thread of a bolt, rod or stem, the device including a first portion to engage with at least one segment of an inner nut of the segmented nut, and a second portion to engage with an outer sleeve of the segmented nut, the device allowing relative rotation of the first portion and second portion for release of the segmented nut, the first portion of the device including at least one region having sufficient clearance for the at least one segment of the inner nut of the segmented nut to release by outward radial movement from engagement with a portion of the thread.

[0058] The first portion of the device may be a one piece component of the device.

[0059] The first portion may include drive receiving means to engagingly receive rotational drive form a drive means. Alternatively, the drive means may be part of the device.

[0060] The first portion may fit within the second portion. The second portion may be a one-piece component of the device. [0061 ] The second portion may include retaining means to retain the first portion at least partially within the second portion. The retaining means may be or may include interference fit within a body portion of the second portion.

[0062] The second portion may include a drive receiving means to receive a drive used to rotate or hold rotation of the second portion relative to the first portion.

[0063] The first drive receiving means and the second portion drive receiving means may each receive drive to counter rotate the first portion and the second portion relative to one another, or to drive the first and second portions in the same rotational direction, or to hold one of the first portion or second portion and rotate the other of those portions.

[0064] The drive receiving means of either or both of the first and second portions may respectively include a square drive arrangement, a star drive arrangement, a hex drive arrangement or a serrated arrangement.

[0065] The first portion may include at least one surface portion that engages in one arrangement with the at least one segment of the inner nut of the segmented nut, and which at least one surface disengages from engagement with the at least one segment of the inner during relative rotation of the inner nut and outer sleeve of the segmented nut to provide the clearance to allow the at least one segment to move radially outwardly and release the segmented nut.

[0066] The at least one surface may have at least one surface contact zone to engage in contact with or adjacent drive portions of the at least one segment, and at least one surface clearance zone which provides the clearance space from the drive portions to allow the segments to move radially outward.

[0067] Preferably the first portion has clearance from an outer surface portion of the segments of the nut at least equal to the depth of a thread to which the nut is attached (i.e. to allow nut segments to move completely out from thread engagement when released).

BRIEF DESCRIPTION OF THE DRAWINGS

[0068] One or more embodiments of the present invention will hereinafter be described with reference to the accompanying Figures, in which:

[0069] Figure 1 shows a perspective view of a device according to an embodiment of the present invention.

[0070] Figure 2 shows a partial section through the perspective view shown in Figure 1 .

[0071 ] Figure 3 shows an exploded lower perspective view of the embodiment shown in Figures 1 and 2.

[0072] Figure 4 shows a perspective view of a segmented nut for use with at least one embodiment of the present invention.

[0073] Figures 5a to 5c show stages in rotating an inner nut and outer sleeve of a 'castellated' segmented nut by engagement of a device according to an embodiment of the present invention. Figure 5a shows the engagement portions of the device engaging into recesses formed between projections of the inner nut segments. Figure 5b shows the inner nut and outer sleeve of the segmented nut rotated relative to one another to a release position allowing the outer sleeve to be removed, the engagement portions of the present device shown engaged in the recesses and the segments have clearance to move radially. Figure 5c shows the segments of the segmented nut in a release position and moved radially toward the outer sleeve, which accommodates thread expansion of the thread of the shaft passing through the segmented nut. [0074] Figure 6 shows a perspective view of a device according to a further embodiment of the present invention.

[0075] Figure 7 shows a vertical cross sectional view through the device according to the embodiment of Figure 6.

[0076] Figure 8 shows a bottom view into the opening into the device of Figures 6 and 7, the opening arranged to receive the segmented nut.

[0077] Figure 9 shows an exploded view of the device shown in Figures 6 to 8.

[0078] Figures 10a to 10c show respective top, perspective and bottom views of a first portion of a device embodying the present invention showing the engagement portions in an inner nut engagement position.

[0079] Figures 1 1 a to 1 1 c show respective top, perspective and bottom views of a first portion of a device embodying the present invention showing the engagement portions radially moved outwards in an inner nut dis-engagement position.

[0080] Figure 12 shows a perspective view of an alternative embodiment of the present invention incorporating biasing to the inner nut engagement portions.

[0081 ] Figure 13 shows a partial cross-sectional view through the device shown in Figure 12.

[0082] Figure 14 shows a bottom view into the opening into the device of Figures 12 and 13, the opening arranged to receive the segmented nut. [0083] Figure 15 shows an exploded view of the device shown in Figures 12 to 14.

[0084] Figure 16 (consistent with Figure 18) shows a cross sectional view of inner nut engagement portions of the device in an engagement position according to an embodiment of the present invention.

[0085] Figure 17 (consistent with Figure 19) shows the cross-sectional view of the inner nut engagement portions of Figure 16 with the engagement portions in their released position moved radially outwards relative to one another

[0086] Figure 18 shows a partial cross-sectional view of an engagement portion biasing mechanism with engagement portions radially inwards to engage with the inner nut of a segmented nut.

[0087] Figure 19 shows the partial cross-sectional view of Figure 18 of an engagement portion biasing mechanism with the engagement portions radially outwards for disengagement with the inner nut of a segmented nut.

[0088] Figure 20 shows a perspective view of a device according to an alternative embodiment of the present invention.

[0089] Figure 21 shows a partial cross section of the device shown in Figure 20.

[0090] Figure 22 shows the profile engaging on the top of the segments of the segmented nut

[0091 ] Figure 23 shows the segments of the segmented nut in their release position, the top profile allowing for clearance. [0092] Figure 24 shows an exploded view of the embodiment shown in Figures 20 to 23.

[0093] Figures 25A and 25B show sectional views of an alternative

embodiment of a device for applying release torque to a multi-part nut. Figure 25A shows the device applied to a multi-part nut with the nut in a

tightened/assembled configuration. Figure 25B shows the device applied to the multi-part nut in the released position allowing the inner segments to move radially.

[0094] Figures 26A and 26B show perspective views of a multi-part nut according to an embodiment of the present invention with a representation of part of a device for applying a torque to a lower part of the nut. Figure 26A shows the multi-part nut with the nut in a tightened/assembled configuration. Figure 26B shows the multi-part nut in the released position allowing the inner segments to move radially.

[0095] Figures 27A and 27B show perspective views of a multi-part nut according to an embodiment of the present invention. Figure 27A shows the multi-part nut with the nut in a tightened/assembled configuration. Figure 27B shows the multi-part nut in the released position allowing the inner segments to move radially.

[0096] Figures 28A and 28B show plan views of a multi-part nut according to an embodiment of the present invention with a representation of part of a device for applying a torque to a lower part of the nut. Figure 28A shows the multi-part nut with the nut in a tightened/assembled configuration. Figure 28B shows the multi-part nut in the released position allowing the inner segments to move radially.

[0097] Figures 29A and 29B show plan views of a multi-part nut according to an embodiment of the present invention. Figure 29A shows the multi-part nut with the nut in a tightened/assembled configuration. Figure 29B shows the multipart nut in the released position allowing the inner segments to move radially outward.

[0098] Figures 30A to 30D, 31 A, 31 B, 32A and 32D show a multi-part nut according to an embodiment of the present invention. In particular, Figures 30A to 30D show a device according to an embodiment of the present invention in combination with the aforementioned nut.

DESCRIPTION OF PREFERRED EMBODIMENT

[0099] A device according to the present invention can be used to engage with and release segmented nuts without the need for a reaction arm.

[00100] A device 10 embodying the present invention shown in Figures 1 to 3 includes a second portion 12 and a first portion 14 arranged to rotate relative to one another with the first portion disposed at least partially within the second portion.

[00101 ] The second portion provides a housing or body to receive, and which may preferably retain, the first portion.

[00102] The second portion has an opening 16 configured to be engaged with a drive means of a drive tool, such as a (electric, pneumatic or hydraulic) powered driver or a manual driver.

[00103] The opening 16 includes a drive profilel 8 incorporating a toothed 20 drive to engage with a corresponding profile of a drive means of the

powered/manual driver. This allows releasable engagement of the device from the powered/manual driver. [00104] The first portion 14 includes engagement portions 22 to engage with corresponding recesses on the inner nut of the segmented nut.

[00105] The second portion 12 includes an opening 24 to receive the outer sleeve of the segmented nut. The inward facing surface 26 of the opening is arranged to engage with the outer surface of the outer sleeve of the segmented nut.

[00106] The first portion includes a drive portion 28 which is engaged, in use, with the output portion of the driver. For example, a square drive of a socket type driver.

[00107] In use and engaged with a segmented nut, the driver can either rotate the first portion and retain the second portion static, or rotate the second portion and retain the first portion static, or counter-rotate the inner and second portions relative to one another, to release the segmented nut.

[00108] Figure 4 shows an example of a segmented nut 100 including a castellated inner nut 102 within an outer sleeve 104.

[00109] The engagement portions 22 of a device embodying the present invention such as shown in Figures 1 to 3, but not limited to such a specific embodiment, engage into the recesses 106 between castellation projections 108 provided around an upper end of the inner nut. The inner nut is formed by segments 1 10a-1 10c (more than three segments may be provided).

[001 10] Figures 5a to 5c show stages in rotating an inner nut 102 and outer sleeve 104 of a 'castellated' segmented nut 100 by engagement of a device 10 according to an embodiment of the present invention. [001 1 1 ] Figure 5a shows the engagement portions 22 of the device 10 engaging into recesses 106 formed between projections 108 (forming the castellation) of the inner nut segments 1 10a-1 10c.

[001 12] Figure 5b shows the inner nut 102 and outer sleeve 104 of the segmented nut 100 rotated relative to one another to a release position allowing the outer sleeve 104 to be removed, the engagement portions 22 of the present device shown engaged in the recesses 106 and the segments 1 10a-1 10c have clearance to move radially.

[001 13] Figure 5c shows the segments 1 10a-1 10c of the segmented nut 100 in a release position and moved radially toward the outer sleeve, which

accommodates thread expansion of the thread of the shaft passing through the segmented nut.

[001 14] Figures 6 to 8 show an alternative embodiment of the present invention. Figure 9 shows an exploded view of the device represented in Figures 6 to 8.

[001 15] The device 200 includes a second portion 202 and a first portion 204 in a similar general arrangement to that shown in Figures 1 to 3.

[001 16] Unlike the device shown with reference to Figures 1 to 3 with fixed engagement portions, the alternative device 200 embodying the present invention includes the first portion 204 incorporating moveable engagement portions 206 (e.g. engagement portions 206a-206e).

[001 17] Each engagement portion has an extension 208 that engages into a slot 210 in an upper portion 212 of the first portion 204 allowing the engagement portions to slide radially outward for release of the segments of the nut or inward for engagement with the segments for release of the segmented nut. [001 18] A retainer 212 retains the engagement portions 206 within the second portion 202 and with their extensions 208 in the slots 210 of the upper portion of the first portion.

[001 19] The retainer 212 also engages with the outer sleeve for releasing the segmented nut.

[00120] Figure 9 shows an exploded view of the device 200 shown in Figures 6 to 8. The device 200 has a second portion 202 and a first portion 204, and moveable engagement portions 206 (e.g. engagement portions 206a-206e). Each of the engagement portions has an extension 208 that engages into a respective slot 210 in the upper portion 212 of the first portion 204. Each slot allows the respective engagement portion to slide radially outward for release of the respective segment or to slide inward for engagement with the respective segment for release of the segmented nut.

[00121 ] As mentioned above, the retainer 212 retains the engagement portions 206 within the second portion 202 and with their respective extensions 208 in the slots 210 of the upper portion of the first portion. The retainer 212 also engages with the outer sleeve for releasing the segmented nut.

[00122] It will be appreciated that the device, such as the embodiment of the device shown in Figures 2 to 9 and Figures 12 to 19, can be adapted to be used with a segmented/multi-part nut having a lower flange for each segment, such as the nut shown in Figures 25A through 32B. The moveable engagement portions 206, 306 can be arranged and configured, and be of such shape, as to articulate in use to contact the edges of the segment flanges when releasing the

segmented/multi-part nut and also articulate to provide space so that the segments can move out radially. [00123] Figures 10a to 10c show the engagement portions 206 radially inward towards the centre of the first portion 204 for engagement with the inner nut of a segmented nut. The extensions 208 are in the slots 210.

[00124] Comparing Figures 10a to 10c with Figures 1 1 a to 1 1 c, Figures 1 1 a to 1 1 c show the engagement portions 206 moved radially outwards to disengage with the inner nut and/or to allow expansion of the segments of the inner nut (such as when releasing the prevailing torque on the tightened segmented nut and the threaded shaft to which it is threaded can expand).

[00125] Figures 12 to 15 show an alternative embodiment of the device 300 of the present invention. The device is similar to that show in Figures 6 to 9, with the additional beneficial feature that the engagement portions 306 are biased radially outward by biasing means 307 to a release position.

[00126] Each biasing means 307 is retained in opposed recesses 309, 305. One of the recesses 309 is provided on the extension of the respective engagement portions, and the other recess 305 is provided on an inner face of the respective slot in the upper part 31 1 of the first portion 304.

[00127] The internal surface 313 of the second part has a profile that varies in radial distance from a centre of the device. The profile of the internal surface transitions peripherally between portions closer to and further from the centre. The profile provides a 'cam' surface which forces the engagement portions 306 toward the centre to engage the segments of an inner nut of a segmented nut as the internal surface rotates from the radially more distant 'valleys' 319 from the centre to the radially closer to the centre high portions 317.

[00128] Figures 16 and 18 show examples of the engagement portions 406 radially inward, biased so by the profile of the internal surface 413 of the device. [00129] It will be appreciated that the internal surface 413 provides a cam function such that, during relative rotation of the internal surface and engagement portions, the internal surface has respective 'high' 417 and 'low' 419 portions, the high portions driving the engagement portions towards the centre of the device to engage with the segments of an inner nut of the segmented nut, and the low portions allowing the engagement portions to move radially outward away from the segments of the inner nut allowing the inner nut to release from the thread of a bolt, stud or rod to which the segmented nut is threaded.

[00130] Preferably, the internal surface transitions continuously (smooth continuous transition) or discontinuously (edges or corners) from the high or peak portions 417 to the low or trough portions 419.

[00131 ] When the peak 415 of the respective engagement portion 406 is engaged with the radially inward projection 417 of the internal surface 413, the engagement portion is biased inwards.

[00132] As the second portion 402 and the first portion 404 rotate relative to one another, the engagement portions are allowed to move radially outwards because their respective peaks move into the recess 419 between adjacent radially inward projections 417.

[00133] As shown with respect to in Figures 17 and 19, the engagement portions 406 are biased outwards by the biasing means 407.

[00134] It will be appreciated that the biasing means may include one or more springs or resilient member(s), such as rubber, silicone rubber, urethane or other resilient material.

[00135] Preferably each engagement portion includes an opening 409 to receive at least a portion of the biasing means 407, such as an end of a spring. The first portion may include openings 405 to receive a portion of a respective biasing means.

[00136] The upper portion 41 1 of the first portion 404 provides a reaction member function to react the biasing means 407, and can include a

corresponding opening 405 to receive another portion of the respective biasing means, such as a second end of a spring.

[00137] Figures 20 to 24 show a device, and use of the device, embodying the present invention.

[00138] The device 500 includes a first portion or inner portion 502 provided for rotation within and relative to a second portion or outer portion 504.

[00139] A retaining means 506 retains the inner portion within the outer portion.

[00140] An internal sleeve 508 fits within the second portion and outside of the first portion, and accommodates relative rotation between the first portion and the second portion. The internal sleeve can help to reduce wear and binding between the first and second portions.

[00141 ] The internal sleeve can include or be formed of a resilient material and/or provide an amount of lubrication or at least reduce friction between the first and second portions during relative rotation.

[00142] The internal sleeve internal sleeve may provide a tolerancing

characteristic to ensure fit between the first and second portions is not too loose (which might prevent the nut segments from releasing, yet is not too tight which might prevent relative rotation of the first and second portions. [00143] The retaining means may retain the internal sleeve and the first portion within the second portion by interference fit or by a separate retainer, such as a circlip.

[00144] It will be appreciated that the retaining means 506 has an inner surface 510 which engages with the outer sleeve of the segmented nut. The second portion itself may include such an internal surface to engage with the outer sleeve of the segmented nut, and the retaining means to retain the first portion and/or the internal sleeve may be provided elsewhere.

[00145] It will be appreciated that the retaining means may be attached to the second portion to enable a torque transfer to occur between them.

[00146] The first portion includes an internal surface 512 having contact regions 514 to engage in contact with the segments 522 of the inner nut of the segmented nut. Furthermore, the internal surface 512 includes clearance zones 516 defined by the internal surface being more radially outward from the segments of the nut than the contact regions.

[00147] The internal surface 512 of the first portion 502 engages with the segments of the nut. Relative rotation (preferably in either a clockwise or a counter-clockwise direction) of the first portion and second portion, with the second portion engaged with the sleeve or washer associated with the nut to be released, causes either the segments 522 of the nut or the sleeve or washer to rotate relative to one another.

[00148] Relative counter turning of the first portion with respect to the second portion, such as by 1 /12^th of a full rotation (or other partial rotation amount of a full rotation determined by the specific profile characteristics of the internal surface of the first portion and the segmented nut to be released) provides clearance at the clearance zones for the segments of the nut to move radially outward and to release from engagement with the thread of the bolt, stud or rod to which the nut was fastened.

[00149] Figure 22 shows a counter torque being applied to a segmented nut attached to a bolt (not shown). After sufficient counter torque is applied, a relative motion occurs between the inner segments and outer sleeve of the segmented nut.

[00150] Figure 23 shows the arrangement in Figure 22 after approximately 1 /12^th rotation wherein the inner segments 522 of the segmented nut have moved radially outwardly thereby releasing from the bolt thread.

[00151 ] Figures 25A and 25B show an alternative embodiment of a device 600 according to the present invention. The device 600 includes a first portion or inner portion 604 that fits into a second portion or outer portion 602.

[00152] The first portion 604 is arranged to engage with a sleeve 616 of a multi-part nut, such as a segmented nut. The multi-part nut can include segments 614 (e.g. 614A, 614B and 614C). The second portion includes at least one engagement portion 620 arranged and configured to selectively engage a flange portion 618 (e.g. 618A, 618B, 618C) of each segment.

[00153] For example, the flange portions of the segments may form a polygon, such as a hexagon, in plan view when the segments are together forming an inner thread of the multi-part nut. The first portion engages with the sleeve, and relative rotation of the first portion and the second portion allows the second portion to act on one or more of the flange portions of the segments such that the sleeve and the segments rotate relative to one another.

[00154] It will be appreciated that one or other of the sleeve and the segments may remain still while the other moves, or both the sleeve and the segments may rotate relative to one another. Such relative rotation allows the segments to move radially outward into spaces provided by the second portion, as shown, for example, by spaces 719 in Figures 26B and 28B.

[00155] At least one advantage of such an embodiment is that the device can be just two components, the first and second portions. It will however be appreciated that the engagement portion 620 associated with the second portion can be integrally formed with the second portion or can be an added component, such as by welding, riveting or otherwise joining such a component to the second portion. For example, the engagement portion 620 may be provided as a profiled ring (such as shown by way of example as part 716 in Figures 26A, 26B, 28A and 28B.

[00156] The first portion can include a first portion drive receiver 622 and the second portion can include a second portion drive receiver 624.

[00157] Either or both such drive receivers 622, 624 may include a square, a hexagonal, a toothed or other multi faced drive, such as splined. A single tool providing selective drive to one or each of the drive receivers 622, 624 can be provided, such as a selectable rotation drive device, which may include a ratchet type drive.

[00158] The bearing face 626 provided by the flanges of the segments is preferably integral to the flanges/segments.

[00159] As shown by way of example in Figures 26A through 29B, at least one form of the present invention can include a multi-part nut 700. Figures 26A, 27A, 28A and 29A show the nut in an assembled configuration with the segments held by engagement with the sleeve. Figures 26B, 27B, 28B and 29B show the segments released from engagement with the sleeve (though still within the sleeve), but the segments are able to move radially outward to a release orientation. [00160] The nut 700 can include multiple segments 71 OA, 71 OB, 71 OC etc., and an outer sleeve 712 for selectively retaining together the segments to form an inner nut portion defining an inner thread for engagement with a bolt, threaded stud or threaded rod or the like. Releasing the sleeve by relative rotation thereof with respect to the segments allows the segments to move radially outwards and separate, releasing the segmented nut.

[00161 ] The segments can include a flange portion 714A, 714B, 714C, which may extend beyond a widest portion of the sleeve 712. The flange portions when together in the assembled nut can provide an integral washer or bearing face 726 of the segmented nut e.g. provided on/by the underside of the flanges. An outer edge/face 718 (e.g. 718AA, 718AB, 718BA, 718BB, 718CA, 718CB) e.g. can provide a respective drive face or edge of the respective flange portion 714A- 714C for each segment 71 OA-710C. It will be appreciated that the number of, profile of, thickness/height of and/or position of the respective drive edge or face can be selected/provided to suit a particular application or use of the nut.

[00162] As shown by way of example in Figures 26A, 26B, 28A and 28B, the engagement portion 620 (such as a profiled ring 716) may have contact portions 717 which, in use, contact the edges of the peripheral flanges 714A-714C, preferably adjacent to the apexes formed by the flanges.

[00163] A clearance space 719 can be created by the engagement portion 620 (e.g. profiled ring 716) which allows the apexes of the flanges to move radially outward when the segments are released, as shown in Figures 26B and 28B. This may require a small counter rotation of the engagement portion after having acted on the flanges.

[00164] Figures 30A to 30D, 31 A, 31 B, 32A and 32D show a multi-part nut 800 according to an embodiment of the present invention. Figures 30A to 30D show a device 600 according to an embodiment of the present invention in combination with the aforementioned nut. [00165] The multi-part nut includes segments 81 OA-81 OC (though it will be appreciated that the nut may include two segments or more than three

segments.)

[00166] A sleeve or collar 816 can be selectively rotated relative to the segments to either hold the segments together to form an inner nut (as shown in Figures 30A, 30C, 31 A and 32A) or to allow the segments to move radially apart to release the segments (as shown in Figures 30B, 30D, 31 B and 32B).

[00167] Each of the segments can include a respective bearing surface 826.

[00168] As shown by way of example in Figures 30C, 30D, 31 A and 31 B, the multi-part nut may include at least one inner chamfer surface 828 extending between the respective bearing surface 826 and an inner thread portion 832 of the respective segment 81 OA-810C.

[00169] Furthermore, the multi-part nut may include at least one outer chamfer surface 830 extending between the respective bearing surface 826 and an outer edge/face 818AA, 818AB, 818BA, 818BB, 818CA, 818CB (e.g. respective drive face or edge) of the respective flange portion 814A-814C of each segment 81 OA- 810C.

[00170] Preferably, the inner chamfer surface(s) and/or the outer chamfer surface(s) may have an angle of between 10° and 60°, more preferably between 20° and 45°, and even more preferably around 30°, relative to a plane of the bearing surface 826.

Claims

CLAIMS:

1 . A device for use in releasing a segmented nut, the device including a first portion to engage with at least one segment of an inner nut of the segmented nut, and a second portion to engage with an outer sleeve of the segmented nut, the device allowing relative rotation of the first portion and second portion for release of the segmented nut.

2. The device of claim 1 , wherein the device first portion and the device second portion apply torque and counter (reaction) torque to the segmented nut.

3. The device of claim 1 or claim 2, wherein the second portion fits within a recess in the first portion.

4. The device of claim 3, wherein a driver extends into the first portion to drive the second portion.

5. The device of any one of claims 1 to 4, wherein the first portion is arranged and configured to engage with a flange extending from the at least one segment.

6. The device of any one of claims 1 to 5, wherein the first portion includes a multi-faceted drive profile to engage with the at least one segment.

7. The device according to any one of the preceding claims, wherein the first portion and the second portion are coaxial with each other to engage with the respective inner nut and outer sleeve of a segmented nut.

8. The device according to any one of the preceding claims, wherein the first portion is configured to engage with an inner nut of the segmented nut, and the second portion is configured to engage with an outer sleeve of the segmented nut.

9. The device according to any one of the preceding claims, including a clearance between at least part of the first portion and at least part of the second portion.

10. The device according to any one of the preceding claims, the first portion including at least one inner nut engagement means to engage with one or more of the segments of the segmented nut.

1 1 . The device according to claim 10, the inner nut engagement means including at least one projection or recess arranged and configured to engage with a corresponding at least one receiver or projection provided on the

respective segment(s) of the inner nut.

12. The device according to claim 1 1 , wherein the inner nut engagement means of the device includes one or more castellation(s) or recess(es) to engage, in use, with respective recess(es) or castellation(s) of the segments.

13. The device according to any one of the preceding claims, wherein the first portion includes a drive portion to receive rotational drive from a drive output of a driver.

14. The device according to claim 13, the drive portion including an aperture to receive a drive member of a driver.

15. The device according to any one of the preceding claims, including a driver to cause relative rotation of the first portion and second portion.

16. The device according to claim 15, the driver including a powered drive being one of electrically, pneumatically or hydraulically operated drive means.

17. The device according to claim 15 or claim 16, a drive input portion of the device arranged to releasably engage with a drive output portion of the powered drive.

18. The device according to any one of the preceding claims, including an internal surface of the second portion having a profile providing a cam action to move the engagement portions inward to engage an inner nut of the segmented nut when the internal surface is rotated to a first position relative to the segments, and allow outward movement of the engagement portions when the internal surface is rotated to a second position relative to the engagement portions.

19. The device according to claim 18, including at least one biasing means providing a biasing force to bias the engagement portions in a radial direction.

20. The device according to claim 19, wherein the biasing means includes a respective resilient device or spring acting between each engagement portion and a reaction member of the first portion.

21 . The device according to any one of the preceding claims, the first portion of the device including at least one region having sufficient clearance for the at least one segment of the inner nut of the segmented nut to release by outward radial movement from engagement with a portion of the thread.

22. The device according to claim 21 , wherein the first portion is a one piece component of the device.

23. The device according to claim 21 or 22, wherein the first portion includes drive receiving means to engagingly receive rotational drive from a drive means or the drive means is part of the device.

24. The device according to claim 21 , wherein the second portion includes retaining means to retain the first portion at least partially within the second portion or the retaining means is an interference fit within a body portion of the second portion.

25. The device according to claim 21 , the first portion including at least one surface portion that engages in one arrangement with the at least one segment of the inner nut of the segmented nut, and which at least one surface disengages from engagement with the at least one segment of the inner during relative rotation of the inner nut and outer sleeve of the segmented nut to provide the clearance to allow the at least one segment to move radially outwardly and release the segmented nut.

26. The device according to claim 25, the at least one surface having at least one surface contact zone to engage in contact with or adjacent drive portions of the at least one segment, and at least one surface clearance zone which provides the clearance space from the drive portions to allow the segments to move radially outward.

27. The device according to any one of claims 21 to 26, wherein, at least one relative orientation of the first portion relative to segments of the segmented nut, the first portion has clearance from an outer surface portion of the segments of the nut at least equal to the depth of a thread to which the nut is attached.

28. The device according to claim 27, wherein the first portion includes an internal surface having contact regions to engage in contact with the segments of the inner nut of the segmented nut.

29. The device according to claim 28, wherein the internal surface includes clearance zones defined by the internal surface being more radially outward from the segments of the nut than the contact regions.

30. A segmented nut including an inner nut including at least two segments, each segment including part of an internal thread for engagement with a thread of a shaft, and an outer sleeve for retaining the segments together in one rotational orientation of the outer sleeve and allowing separation of the segments in another rotational orientation of the outer sleeve, the inner nut including at least one receiver for engagement with a device for releasing the segmented nut.

31 . The segmented nut of claim 30, wherein the inner nut includes the at least one receiver at an upper portion thereof for engagement with a device for releasing the segmented nut.

32. The segmented nut of claim 30, wherein the inner nut includes the at least one receiver at a lower portion thereof for engagement with a device for releasing the segmented nut.

33. The segmented nut of claim 32, wherein the lower portion includes a flange projecting transversely with respect to hole through the inner nut formed by the segments.

34. The segmented nut of claim 33, wherein the flange provides a contact surface of the segmented nut for contact with a workpiece, spacer or washer.

35. The segmented nut of claim 34, wherein the contact surface includes an annular bearing surface which projects away from, or provides a step from an edge of the flange, or is inset from an edge of the flange.

36. The segmented nut of any one of claims 32 to 35, wherein the at least one receiver at the lower portion of the inner nut includes an edge profile arranged and configured to engage with the device for releasing the segmented nut.

37. The segmented nut of claim 36, wherein the edge profile includes a multi- faceted surface in plan view.

38. The segmented nut of claim 37, wherein the edge profile is hexagonal in plan view with faces/sides of the hexagon formed by the flange of the segments of the inner nut.

39. The segmented nut of any one of claims 30 to 38, including at least one inner chamfer surface extending between a bearing surface of each said segment and an inner thread portion of each said segment and/or an outer chamfer surface extending between the bearing surface of each said segment and an outer edge of a respective flange portion of each said segment.

40. The segmented nut of claim 39, wherein the the inner chamfer surface(s) and/or the outer chamfer surface(s) has/have an angle of between 10° and 60° relative to a plane of the bearing surface.

41 . The segmented nut of claim 40, wherein the angle is between 20° and 45°.

42. The segmented nut of claim 41 , wherein the angle is around 30°.

43. The segmented nut of claim 31 , including the at least one receiver including castellation at an upper portion of the inner nut arranged to receive at least one engagement portion of the device.

44. A device for use in rotating a segmented nut in engagement with a thread of a bolt, rod or stem, the device including a first portion to engage with at least one segment of an inner nut of the segmented nut, and a second portion to engage with an outer sleeve of the segmented nut, the device allowing relative rotation of the first portion and second portion for release of the segmented nut, the first portion of the device including at least one region having sufficient clearance for the at least one segment of the inner nut of the segmented nut to release by outward radial movement from engagement with a portion of the thread.

45. The device according to claim 44, wherein the first portion is a one-piece component of the device.

46. The device according to claim 44 or 45, wherein the first portion includes drive receiving means to engagingly receive rotational drive form a drive means.

47. The device according to claim 44 or 45, wherein the device includes an integrated drive means.

48. The device according to claim 44, wherein the first portion fits within the second portion.

49. The device according to any one of claims 44 to 48, wherein the second portion is a one-piece component of the device.

50. The device according to any one of claims 44 to 49, the second portion including retaining means to retain the first portion at least partially within the second portion.

51 . The device according to claim 46, the retaining means including

interference fit within a body portion of the second portion.

52. The device according to any one of claims 44 to 51 , the first portion including at least one surface portion that engages in one arrangement with the at least one segment of the inner nut of the segmented nut, and which at least one surface disengages from engagement with the at least one segment of the inner during relative rotation of the inner nut and outer sleeve of the segmented nut to provide the clearance to allow the at least one segment to move radially outwardly and release the segmented nut.

53. The device according to claim 52, the at least one surface having at least one surface contact zone to engage in contact with or adjacent drive portions of the at least one segment, and at least one surface clearance zone which provides the clearance space from the drive portions to allow the segments to move radially outward.

54. The device according to any one of claims 44 to 53, the first portion having clearance from an outer surface portion of the segments of the nut at least equal to the depth of a thread to which the nut is attached.

55. A system or device for releasing a segmented nut, the system or device including a first portion to engage with a nut first part, and a second portion to engage with a nut second part, the first portion and the second portion arranged to counteract torque with respect to one another.