AU2021203268A1

AU2021203268A1 - Fastener allowing single side access

Info

Publication number: AU2021203268A1
Application number: AU2021203268A
Authority: AU
Inventors: Michael Harris
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-05-25
Filing date: 2021-05-21
Publication date: 2021-12-09

Abstract

A one-sided fastener is arranged for insertion from one side of a wear liner. The fastener includes pivoting members which can be activated by a screw to extend radially and form a bearing surface on the inside. Further rotation of the screw causes the bearing surface to be drawn towards a head of the screw, fastening the wear liner to its base. 1/4 102 12 104 -101 I0610 10010 14 98 72 747 70 60 1 '68 16 ---- 76 6 64 80 62 66 78 18 2 206 30:30 22 4 24 26 Fig. 1

Description

1/4 102

12 104

-101 I0610 10010

14 98

70 747 72 60

16 ---- 1'68 76 6 64 80 62 66 78

18 2

30:30

206

22 4

24

26

Fig. 1

AUSTRALIA

Patents Act 1990

COMPLETE SPECIFICATION

Invention title:

"FASTENER ALLOWING SINGLE SIDE ACCESS"

Applicant:

HARRIS, MICHAEL

Associated provisional applications: Application number 2020901690 filed 25 May 2020

The following statement is a full description of the invention, including the best method of performing it known to me:

"FASTENER ALLOWING SINGLE SIDE ACCESS"

Field of the Invention

[0001] The present invention relates to nut-and-bolt type fasteners for connection of two members where the fastener can be secured from one side of the members only. It has been developed for the connection of wear liners of crushers, transfer chutes, and similar mining equipment, but is considered to have broader application.

Background to the Invention

[0002] Sacrificial wear linings are commonly used to protect structural surfaces in mining operations. Typically made of abrasion-resistant materials such as ceramic materials, the wear linings are fastened to internal steel surfaces of machines such as crushers or mills, and to other production line assets such as hoppers and transfer chutes.

[0003] In many instances, it is possible to secure a wear lining to a base by means of a nut-and-bolt arrangement. In such instances, a bolt can be passed into aligned apertures in the wear lining and the base, and secured by a nut located outside the base. This is a two-person operation, with one operating the bolt head from inside the wear lining and the other tightening the nut from outside the base.

[0004] Often, however, it is difficult or impractical to access the outside of the base. In these circumstances, it is necessary to secure the wear lining to the base from one side only (that is, the wear lining side).

[0005] One way of achieving this is to fix some style of fastener receiving element to the base. This approach is limited in its effectiveness. It requires precise alignment of the wear lining to the base, which may be difficult. The connection may not be sufficiently strong to withstand the forces applied during use. Further, should the fastener receiving element become damaged or worn then it requires replacement, which may need to be done with one sided access.

[0006] Welding of wear liners to base surfaces is only possible where the wear liner is metallic. Further, the use of welding devices in confined and enclosed spaces such as the inside of a crusher is problematic and dangerous.

[0007] One solution to the problem is the use of fasteners passing through non-circular apertures in both wear lining and base. This style of fastener is shaped such that it will pass through aligned apertures in one orientation, but can then be rotated to a second orientation which prevents its reverse passage.

[0008] While effective, such fasteners can be difficult to employ as they require alignment of the apertures of wear lining and base not only in position but also in orientation. The formation of precisely shaped apertures in both wear lining and base can also be problematic.

[0009] The present invention seeks to provide a fastener which can be operated by a single person, from only one side of a connection, through a circular aperture.

Summary of the Invention

[0010] According to one aspect of the present invention there is provided a fastener having a body and an activating member, the body having a head portion, a central portion, and a tail portion, the tail portion including at least one bearing surface, the tail portion being moveable between a first orientation in which the bearing surface is substantially within the central portion and a second orientation in which the bearing surface extends generally radially from the central portion, such that in its first orientation the tail portion has a first effective width, and in its second orientation the tail portion has a second effective width, the second effective width of the tail portion being greater than an effective width of the central portion; movement of the tail portion between the first and second orientations being effected by axial movement of the activating member through the body towards the tail portion, the tail portion further including at least one stopping surface which engages when the tail portion is in its second orientation and limits movement of the bearing surface beyond a generally radial position.

[0011] It is preferred that the central portion of the body is circular in cross section, with the effective width being its diameter.

[0012] It is preferred that the effective width of the tail portion in its first orientation is equal to the effective width of the central portion.

[0013] In a preferred embodiment the tail portion includes at least one pivot member having an inner end and an outer end, the inner end of the pivot member being arranged to move in a generally radial direction to effect movement of the tail member between the first and second orientations.

[0014] The pivot member is preferably arranged to be aligned in an axial direction when the tail member is in its first orientation.

[0015] The stopping surface of the tail portion is preferably located at or near an outer end of the pivot member.

[0016] It is preferred that the tail portion includes a fulcrum-defining member located closer to the outer end than to the inner end of the pivot member. The fulcrum-defining member is preferably circular.

[0017] In a preferred embodiment the tail portion includes at least three pivot members angularly spaced around a circumference of the body.

[0018] The tail portion may include a biasing member arranged to return the tail portion to its first orientation upon withdrawal of the activating member.

[0019] The fastener may have a mounting collar, the mounting collar having a central bore within which the head portion of the body may locate. The mounting collar may be externally threaded. Alternatively, the mounting collar may be arranged to be welded into position.

[0020] In a preferred embodiment, the central bore of the mounting collar has a first portion sized to receive the central portion of the body, a second portion having a greater diameter than the first portion and being sized to receive the head of the body, and a third portion having a greater diameter than the second portion and being sized to receive a head-receiving member.

[0021] The head-receiving member preferably has a central aperture through which a shank of the activating member can pass. In a preferred embodiment the central aperture is countersunk so as to receive a complementary shaped head of the activating member.

[0022] The head-receiving member may be a circlip.

[0023] In a preferred embodiment there is an axial space between the head portion of the body and the head-receiving member when the tail portion is in its first orientation.

[0024] It is preferred that the activating member has an externally threaded shank, and that the body includes an axially extending internally threaded aperture arranged to receive the threaded shank.

[0025] The activating member may have an engaging end remote from a head of the activating member, the engaging end being arranged to engage with the inner end of the pivot member and to urge it outward in a radial direction.

[0026] In accordance with a second aspect of the present invention there is provided a fastener having a body, an activating member, and a mounting collar; the body having a central portion and a tail portion, the tail portion being moveable between a first orientation having a first effective width and a second orientation having a second effective width, the second effective width of the tail portion being greater than an effective width of the central portion; movement of the tail portion between the first and second orientations being effected by threaded axial movement of the activating member through the body towards the tail portion when the body is in a first position relative to the mounting collar, the body being axially moveable relative to the mounting collar when the tail portion is in its second orientation, movement of the body relative to the mounting collar being effected by rotation of the activating member.

[0027] In accordance with a third aspect of the present invention there is provided a method of attaching a wear liner to a base, the method including the steps of: locating the wear liner against the base such that an aperture in the wear liner aligns with an aperture of the base to form an aligned aperture; introducing a fastener into the aligned aperture from outside the wear liner, the fastener having a body and an activating member; locating the fastener such that a tail of the body protrudes from the aligned aperture outside the base; moving the activating member relative to the body such that a tail of the body increases its effective width to be greater than that of the aligned aperture; and tightening the fastener such that the tail of the body moves towards and engages the base.

[0028] The step of moving the activating member relative to the body preferably continues until a stopping surface of the tail of the body engages with another surface to prevent further change in the effective width of the tail of the body.

[0029] The method may include the step of locating a mounting collar within the aperture of the wear liner before the step of aligning the apertures.

[0030] The fastener may be introduced into the wear liner before the aligning of the apertures.

[0031] The activating member may have a threaded shank, such that tightening of the fastener is achieved by rotation of the activating member along a threaded path of the body.

Brief Description of the Drawings

[0032] It will be convenient to further describe the invention with reference to preferred embodiments of the present invention. Other embodiments are possible, and consequently the particularity of the following discussion is not to be understood as superseding the generality of the preceding description of the invention. In the drawings:

[0033] Figure 1 is an exploded view of a fastener in accordance with the present invention;

[0034] Figure 2 is a side view of the fastener of Figure 1 when assembled, with a tail portion in a first orientation;

[0035] Figure 3 is a cross section through the assembled fastener of Figure 2;

[0036] Figure 4 is a side view of a tail piece within the fastener of Figure 1;

[0037] Figure 5 is a cross section through the assembled fastener of Figure 2, with the tail portion in a second orientation; and

[0038] Figures 6 to 8 are sequential cross sectional views of the fastener of Figure 1 in use.

Detailed Description of Preferred Embodiments

[0039] Figure 1 shows a fastener 10 in an exploded view. The fastener 10 has a number of components: an activating member being an activating screw 12; a head receiving member being a circlip 14; a body including an outer casing 16; a mounting collar 18; a tail portion 20 arranged for insertion within the outer casing 16; a biasing member being an annular spring 22; a fulcrum defining member being a ring 24, and a cap 26.

[0040] The tail portion 20 comprises three pivot members, being tail pieces 30. A single tail piece 30 is shown in Figure 4. The tail piece 30 has a concave inside wall 32 which extends around 120°. The arrangement is such that the three tail pieces 30 can be held together such that their inside walls 32 combine to form a central cylindrical bore 34 passing through the tail portion 20.

[0041] Each tail piece 30 has a convex outside wall 36, and two parallel side walls 38 extending between the inside wall 32, and the outside wall 36.

[0042] The tail piece 30 has an inner axial end 40 and an outer axial end 42. A fulcrum notch 44 extends circumferentially across the outside wall 36, approximately 20% of the way from the outer axial end 42 to the inner axial end 40. A containing notch 46 extends circumferentially across the outside wall 36, approximately 25% of the way from the inner axial end 40 to the outer axial end 42.

[0043] The tail piece 30 is of a stepped configuration, with an outer portion 48 between the fulcrum notch 44 and the outer axial end 42 having a smaller radial width than a main portion 50 between the fulcrum notch 44 and the inner axial end 40.

[0044] The inner axial end 40 has a top surface 52 having three regions: a first region 54 extending upwardly and outwardly from the inside wall 32, a second region 56 extending outwardly and downwardly from the first region 54, and a third region 58 extending from the second region 56 to the outside wall 36 at a slight incline. The first region 54 and the second region 56 are of about the same radial extent, with the third region 58 being about three times the radial extent of the first region 54.

[0045] The outer casing 16 of the fastener 10 is generally cylindrical. It extends in an axial direction from a head end 60 to a tail end 62. Three radial slots 64 extend from the tail end 62 towards the head end 60. The radial slots

64 are arranged to receive the tail portion 20. Each radial slot 64 has an inwardly facing abutment surface 65 remote from the tail end 62.

[0046] The outer casing 16 is divided into three portions: a outer portion 66, a central portion 68, and head portion 70. The outer portion 66 is defined by the axial extent of the radial slots 64. The central portion 68 is cylindrical, having the same diameter as the outer portion 66, and extends between the outer portion 66 and the head portion 70. The head portion 70 is generally annular, having a diameter greater than that of the central portion 68. A locating notch 72 is formed on an outer circumference of the head portion 70.

[0047] The outer casing 16 has an internally threaded bore 74 extending axially from the head end 60 towards the tail end 62.

[0048] The outer casing 16 has a first circumferential groove 76 located within the outer portion 66. The first circumferential groove 76 is arranged to align axially with the containing notches 46 of the tail portion 20.

[0049] The outer casing 16 has a second circumferential groove 78 located towards the tail end 62 of the outer portion 66. The second circumferential groove 78 is arranged to align axially with the fulcrum notches 44 of the tail portion 20.

[0050] An externally threaded cap-receiving portion 80 extends from the second circumferential groove 78 to the tail end 62.

[0051] The cap 26 is internally threaded, and is sized and shaped so as to engage with the cap-receiving portion 80 of the outer casing 16.

[0052] The body of the fastener 10 is assembled by inserting the tail portion into the outer casing 16, locating the ring 24 into the second circumferential groove 78, locating the annular spring 22 into the first circumferential groove 76, and screwing the cap 26 onto the cap-receiving portion 80 to maintain the tail portion 20 in a fixed axial position. When thus assembled, the tail portion is contained within the outer portion 66 of the outer casing 16. This represents a first orientation of the tail portion, whereby its diameter is the same as that of the central portion 68.

[0053] The mounting collar 18 is generally hollow-cylindrical, with a first axial end 82 and a second axial end 84. It has an inner bore 86 of varying radius. The inner bore 86 has a first portion 88 at the first axial end 82, the first portion 88 having a radius complementary to the central portion 68 of the outer casing 16. The first portion 88 represents an axial length approximately 15 percent of the mounting collar 18.

[0054] The inner bore 86 tapers outwardly from the first portion 88 to a second portion 90, the second portion having a radius complementary to the head portion 70 of the outer casing 16. The first and second portions 88, 90, together with the tapered join, represent an axial length of about 70% of the mounting collar 18.

[0055] The inner bore 86 has a step-change in radius from the second portion to a third portion 92, located at the second axial end 84. The third portion 92 has a slightly tapered radius, having its maximum at the step-change and its minimum at the second axial end 84. The third portion 92 has an average radius about 20% than that of the second portion 90.

[0056] The inner bore 86 has a post 94 extending upwardly from the tapered join between the first portion 88 and the second portion 90. The post 94 is arranged to receive the locating notch 72.

[0057] In the embodiment shown the mounting collar 18 has an externally threaded outer wall 96.

[0058] The circlip 14 is generally annular, with a tapered circumferential surface sized and shaped to locate within the third portion 92 of the inner bore 86. The circlip 14 has a central bore 98 arranged to align with the inner bore 86 of the outer casing 16. The circlip 14 has an outwardly facing surface 100.

The central bore 98 is countersunk on the outwardly facing surface 100, such that a head 102 of the activating screw 12 is able to be received within a receiving portion 101 the outwardly facing surface 100.

[0059] The activating screw 12 has a threaded shank 104 arranged to engage within the internally threaded bore 74 of the outer casing 16. The threaded shank 104 terminates in a rounded engaging end 106.

[0060] The general operation of the fastener 10 is as follows: the activating screw 12 is screwed towards the cap 26. At a certain depth, the engaging end 106 comes into contact with the first region 54 of the top surface 52 of the tail pieces 30.

[0061] The outer axial ends 42 of the tail pieces 30 are held in relative radial position by the ring 24. This means that continued movement of the screw 12 forces the inner axial ends 40 of the tail pieces 30 to move in a radially outward direction. Each tail piece 30 pivots about the ring 24.

[0062] The pivoting of each of the tail pieces 30 finishes when the second region 56 of the top surface 52 abuts the inwardly facing abutment surface 65 of the outer case 16. This is shown in Figure 5. It will be appreciated that the second region 56 is acting as a stopping surface of the tail piece 30, preventing further pivoting of the tail piece 30.

[0063] In this position the third region 58 of the top surface 52 extends radially outside the outer casing 16. In effect, this increases the effective diameter of the tail portion 20. This represents a second orientation of the tail portion 20. The third region 58 of the top surface 52 forms a bearing surface of the fastener 10.

[0064] When the activating screw 12 is withdrawn, the annular spring 22 provides a biasing force which draws the tail portion 20 back to its first orientation.

[0065] Use of the fastener 10 in fixing a wear lining 200 to a base 202 is shown in Figure 6 to 8.

[0066] The base 202 in this embodiment is a 10mm mild steel plate. The wear lining 200 is a 25mm ceramic lining, bonded via a 6mm rubber layer 204 to a 6mm backing plate 206.

[0067] An internally threaded aperture 208 has been machined into the backing plate 206, arranged for receipt of the mounting collar 18. It will be appreciated that in an alternative embodiment a non-threaded mounting collar could be welded within a backing plate 206.

[0068] A 16mm hole 210 has been bored through the wear lining 200, co axial with the aperture 208. A 20mm hole 212 has been bored through the base 202.

[0069] The fastener 10 is assembled by fixing the tail portion 20 into the outer casing 16 to produce the fastener body, locating the fastener body within the mounting collar 18 such that the head portion 70 is located within the second portion 90 of the inner bore 86 and the central portion 68 extends through the second axial end 84, locating the circlip 14 within the third portion 92 of the inner bore 86, and loosely locating the activating screw 12 within the internally threaded bore 74 of the fastener body.

[0070] The mounting collar 18 can then be screwed into position within the aperture 208 of the backing plate 206, with the activating screw 12 extending into the hole 210.

[0071] The wear lining 200 is then located in the desired position relative to the base 202, such that the tail portion 20 of the fastener 10 extends through the hole 212. This arrangement is shown in Figure 6. It will be appreciated that in this arrangement any axial force applied to the head 102 of the activating screw 12 will push the body of the fastener 10 away from the circlip 14, creating a gap 220 between the head portion 70 and the circlip 14.

[0072] Rotation of the activating screw 12 causes the tail portion 20 of the fastener 10 to move into its second orientation, as described above. In its second orientation the effective diameter of the tail portion 20 is greater than that of the hole 212. This is shown in Figure 7. Rotation of the activating screw 12 relative to the mounting collar 18 continues until the head 102 of the activating screw 12 is received in the receiving portion 101 of the circlip 14.

[0073] From this point, the activating screw 12 is unable to move relative to the mounting collar 18. Further rotation of the activating screw 12 instead acts to draw the body of the fastener towards the circlip 14. This causes the protruding third regions 58 of the tail portion 20 to engage with, and bear against, an outer surface 214 of the base 202. Further rotation simply tightens the fastener to the position shown in Figure 8.

[0074] Removal of the fastener can be achieved by simply reversing of the above steps, with the annular spring 22 causing the tail portion 20 of the fastener to return to its first orientation whereby it can be readily drawn through the hole 212.

[0075] Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Claims

Claims 1. A fastener having a body and an activating member, the body having a head portion, a central portion, and a tail portion, the tail portion including at least one bearing surface, the tail portion being moveable between a first orientation in which the bearing surface is substantially within the central portion and a second orientation in which the bearing surface extends generally radially from the central portion, such that in its first orientation the tail portion has a first effective width, and in its second orientation the tail portion has a second effective width, the second effective width of the tail portion being greater than an effective width of the central portion; movement of the tail portion between the first and second orientations being effected by axial movement of the activating member through the body towards the tail portion, the tail portion further including at least one stopping surface which engages when the tail portion is in its second orientation and limits movement of the bearing surface beyond a generally radial position.
2. A fastener as claimed in claim 1, wherein the central portion of the body is circular in cross section, with the effective width being its diameter.
3. A fastener as claimed in claim 1 or claim 2, wherein the effective width of the tail portion in its first orientation is equal to the effective width of the central portion.
4. A fastener as claimed in any preceding claim, wherein the tail portion includes at least one pivot member having an inner end and an outer end, the inner end of the pivot member being arranged to move in a generally radial direction to effect movement of the tail member between the first and second orientations.
5. A fastener as claimed in claim 4, wherein the pivot member is arranged to be aligned in an axial direction when the tail member is in its first orientation.
6. A fastener as claimed in claim 4 or claim 5, wherein the stopping surface of the tail portion is located at or near an outer end of the pivot member.
7. A fastener as claimed in any one of claims 4 to 6, wherein the tail portion includes a fulcrum-defining member located closer to the outer end than to the inner end of the pivot member.
8. A fastener as claimed in claim 7, wherein the fulcrum-defining member is circular.
9. A fastener as claimed in any one of claims 4 to 8, wherein the tail portion includes at least three pivot members angularly spaced around a circumference of the body.
10. A fastener as claimed in any preceding claim, wherein the tail portion includes a biasing member arranged to return the tail portion to its first orientation upon withdrawal of the activating member.
11. A fastener as claimed in any preceding claim, wherein the fastener has a mounting collar, the mounting collar having a central bore within which the head portion of the body may locate.
12. A fastener as claimed in claim 11, wherein the central bore of the mounting collar has a first portion sized to receive the central portion of the body, a second portion having a greater diameter than the first portion and being sized to receive the head of the body, and a third portion having a greater diameter than the second portion and being sized to receive a head receiving member, the head-receiving member having a central aperture through which a shank of the activating member can pass.
13. A fastener as claimed in claim 12, wherein there is an axial space between the head portion of the body and the head-receiving member when the tail portion is in its first orientation.
14. A fastener as claimed in any preceding claim, wherein the activating member has an externally threaded shank, and the body includes an axially extending internally threaded aperture arranged to receive the threaded shank.
15. A fastener as claimed in any one of claims 4 to 9, wherein the activating member has an engaging end remote from a head of the activating member, the engaging end being arranged to engage with the inner end of the pivot member and to urge it outward in a radial direction.
16. A fastener having a body, an activating member, and a mounting collar; the body having a central portion and a tail portion, the tail portion being moveable between a first orientation having a first effective width and a second orientation having a second effective width, the second effective width of the tail portion being greater than an effective width of the central portion; movement of the tail portion between the first and second orientations being effected by threaded axial movement of the activating member through the body towards the tail portion when the body is in a first position relative to the mounting collar, the body being axially moveable relative to the mounting collar when the tail portion is in its second orientation, movement of the body relative to the mounting collar being effected by rotation of the activating member.
17. A method of attaching a wear liner to a base, the method including the steps of: locating the wear liner against the base such that an aperture in the wear liner aligns with an aperture of the base to form an aligned aperture; introducing a fastener into the aligned aperture from outside the wear liner, the fastener having a body and an activating member; locating the fastener such that a tail portion of the body protrudes from the aligned aperture outside the base; moving the activating member relative to the body such that a tail of the body increases its effective width to be greater than that of the aligned aperture; and tightening the fastener.
18. A method of attaching a wear liner to a base as claimed in claim 16, wherein the step of moving the activating member relative to the body includes the increase in effective width of the tail portion of the body until a stopping surface of the tail portion of the body engages with another surface to prevent further change in the effective width of the tail portion of the body.
19. A method of attaching a wear liner to a base as claimed in claim 16 or claim 17, wherein the fastener is introduced into the wear liner before the aligning of the apertures.
20. A method of attaching a wear liner to a base as claimed in any one of claims 16 to 18, wherein the activating member has a threaded shank, such that tightening of the fastener is achieved by rotation of the activating member along a threaded path of the body.

HARRIS, MICHAEL By his Patent Attorneys ARMOUR IP

P2358AU00