NZ199613A

NZ199613A - Friction pivot joint for stay

Info

Publication number: NZ199613A
Application number: NZ19961382A
Authority: NZ
Inventors: R J Bigley; J E Douglas
Original assignee: Shaw Mfg Ltd
Priority date: 1981-02-02
Filing date: 1982-02-01
Publication date: 1984-05-31
Also published as: IE820225L; IE52324B1; AU7966982A; GB2092220B; AU549196B2; GB2092220A

Description

199613 2. 5L . fl /• 2 Priority Date(s}: Complex Specification Filed Publication Dsta: . - .1984... .

P.O. Joirn.-H, No\ 125% iiiiiiiiiiii* ;Patents Form No.5 ;NEW ZEALAND PATENTS ACT 19 53 COMPLETE SPECIFICATION "IMPROVEMENTS IN STAYS FOR WINDOWS" ;\'V^ ;I/WE ARTHUR SHAW MANUFACTURING LIMITED, a Company incorporated ;U) o-vtc& Qos^-vi-uLO and registered in England, of PiOi Duji iBl, Willenhall, West ;Midlands, England, WV13 2AS, ;hereby declare the invention, for which ^f/we pray that a patent may be granted to igfe/us,,and the method by which it is to be performed, to be particularly described in and by the following statement:- ;r— ;199613 ;01 This invention concerns improvements in stays designed and arranged to mount a sash (as hereinafter defined) on a frame for adjustable movement relative to the frame, in particular but not exclusively, stays for 05 windows. ;The term "sash" as used herein means a closure member adjustable relative to a frame and arranged to close an aperture in the frame. The term "sash" is deemed to include a glazed light for top, bottom or 10 side opening, or a non-glazed or partly glazed member such as a fan-light, door or casement. ;Various types of stays are already known in which arms or links and mounting plates or brackets are connected together by pivot joints. The arms or links 15 extend between the sash and the frame to which they are pivotally connected by mounting plates or brackets. In such use of stays, a sash is supported on each of two opposed sides by a respective stay. The arrangement of the stays is such that the stays fold up and are 20 confined within the rebate between the sash and the frame when the sash is closed, and for opening and closing movement of the sash, the stays act as hinges with the arms or links pivotting relative to the plates or brackets. The links may comprise two or more 25 elements pivotted together, and possibly interconnecting one or more arms. ;As will be appreciated, in use the sash cannot be permitted to pivot freely on such stays, and some form of restraint is required, and the possible provision of 30 a locking or holding device acting between the sash and the frame. ;In some types of stay, frictional restraint is provided by having one of the arms pivotaly connected to a sliding shoe which can move relative to a special ;-3- ;199613 ;mounting plate. The sliding shoe sometimes includes means by which the friction for sliding movement is adjustable. With such sliding shoe stays, the pivotal connections are usually rivets. ;In other types of stays, the frictional restraint is provided by the rivetted pivot joints in which the rivet is clinched under pressure to tightly hold the stay parts together. These friction rivet joints, although appearing simple and easy to manufacture, create substantial problems both in manufacture and subsequent use. Particular problems arising in manufacture are due to the tight tolerances required, special control of materials used, and precision in rivetting to obtain and maintain the requisite tension in the rivet. Problems in use arise from the loads which have to be supported by the stay, such as the glazed weight of the sash and substantial wind loads when the stay is extended. There are also the abusive conditions which the stay has to withstand in service, such as weathering, movement of the sash or frame and lack of maintenance. ;These stays are designed in a large number of ways, this being necessary to cope with different dimensions, weights, applications, materials and service conditions as well as customer preferences. It is considered that this invention can be applied to such wide range of stays with pivotal joints that are rivetted, and hereinafter, such types of stays as just described and having rivetted joints are referred to as "of the kind specified". ;It is an object of this invention to provide an improvement in stays of the kind specified by employing a simplified form of pivotal rivet joint which is easy to manufacture, is neat and can be compact. ;1 CO ^ 1 -r ;I 7 / O ! J ;-4- ;01 According to this invention, we provide a stay of the kind specified having first and second elements pivotally connected together by a rivet, the first and second elements are spaced apart by a washer and the 05 rivet extends through the elements and the washer, the head of the rivet engaging the face of the first element remote from the washer, and the tail of the rivet being clinched on the face of-the second element remote from the washer, the second element having a 10 formation in said face into which the tail of the rivet is clinched under pressure to prevent rotation of the rivet relative to the second element. ;The first and second elements may be constituted by any combination of stay parts, for instance, an arm 15 and a plate, two link parts, an arm and a shoe, a plate and a link, a bracket and an arm or the reversals of . the same. ;The clinching pressure applied may be sufficient to provide the frictional restraint within the joint if 20 desired for that particular stay of the kind specified. ;By this invention, a simple joint can be achieved in which the rivet is prevented from rotating relative to one of the stay parts so that a tight and secure rivetted joint can be achieved without providing some 25 form of self-locking device like a spur washer under the rivet tail. ;The invention may be applied to various forms of rivets used for pivotal joints such as hollow, solid or split, and traditional methods of clinching may be 30 employed such as rolling or turning, as appropriate to the particular rivet. ;The formation may be recessed in the face of the second element by being formed in a counter-bore or counter-sink so that the clinched tail of the rivet is ;10 0/17 I y y 6 ] J ;01 contained within such recess and does not stand proud of the face of the second element. Such an arrangement enables a compact joint to be achieved with the clinched tail being housed in the recess. This has the ;05 advantage of preventing damage and entry of detritus into the shank clearance. Furthermore, by providing certain forms of recess, centralisation of the rivet during clinching is ensured. ;The formation may be in the form of serrations 10 formed in the bottom or on the internal wall of the recess. The serrations may be radial or radially spaced with respect the axis of the rivet, and the serrations may have sections or configurations including saw-toothed, crenate, dentate or saw-like. 15 Such formation may be punched or raised in the operation for making the rivet hole in the stay part, such as by punching or piercing. ;Alternatively, the formation may be comprised by a non-circular wall edge of a recess in the stay ;2 0 element. For instance, the formation may comprise a recess having at least two lobes into which the tail of the rivet is clinched. The recess may be of square form into which the tail is clinched. ;The formation need not be recessed in the face but 25 can project or stand proud of the face. The raised formation may be in the form of serrations, teeth, crenulations or the like, and these may extend radially with respect to the rivet axis. Such raised formation can also be provided simply in the manufacturing 30 operation including the piercing or punching of the hole through which the rivet extends. ;In the joint of a stay according to this invention, only a washer is required between the adjacent faces of the first and second elements to ;-6- ;199613 ;01 prevent wear and metal to metal contact between the elements as they pivot relative to one another. The washer may be of plastics material, preferably a low friction material such as acetal or nylon. The washer 05 may be a plastics coated metal washer. ;Preferably the washer is a flat annulus. The thrust face of the second element contacting the washer may be provided by an annular recess or.lip concentric with the rivet axis, and by this provision the thrust 10 area can be predetermined to enable^cl£,se control of the loading to be applied by the rivet when this is in tension to maintain frictional restraint in the stay. Where a recess is provided in the second element, this also serves to locate the washer. Conveniently, such 15 recess or lip may be formed in the pressing or piercing operation applied to the stay element. ;It is also preferred, but not essential, to provide a recess in the first stay element for receiving the washer. ;20 The first stay element may have a counter-bore receiving the head of the rivet or the head may stand proud of the outer face of the stay element. ;As will be understood, as the tail of the rivet is located against rotation, on pivotal movement of the 25 second element, the head of the rivet rotates. ;Preferably, the rivet has a low friction surface and may be treated to obtain such, or may be coated with a plastics material such as nylon. Thus, no washer or other intervening member is required between the first 30 stay element and the rivet head. ;The simplicity of the rivetted joint ensures that only minimum allowance or tolerances for differences in sizing, thickness or flatness etc. have to be accommodated. This has substantial advantages in ;-7- ;199613 ;Oi practice where the rivet is clinched to provide frictional restraint in the joint. ;- Once tooling is provided to form the formations/ no additional manufacturing operation is required to 05 provide the locking of the rivet tail to the stay element. Alignment of the rivet and control of inter-engaging faces can be controlled. ;Other advantages will be apparent from the following description of exemplary embodiments of this 10 invention as depicted in the accompanying drawings. ;The drawings show a first embodiment of this invention wherein ;FIGURE 1 is a perspective view of part of a first element for a stay; ;15 FIGURE 2 is a plan view of the rivetted joint in a stay including the first element shown in Figure 1; and FIGURE 3 is a sectional view of the rivetted joint on line 3-3 of Figure 2. ;The drawings show a second embodiment of this 20 invention wherein:- ;FIGURE 4 is a perspective view of part of a first element for a stay; ;FIGURE 5 is a plan view of the rivetted joint in a stay including the first element shown in Figure 4; and 25 FIGURE 6 is a sectional view of the rivetted joint on line 6-6 of Figure 5. ;The drawings show a third embodiment of this invention wherein:- ;FIGURE 7 is a perspective view of part of a first 30 element for a stay; ;FIGURE 8 is a plan view of the rivetted joint in a stay including the first element shown in Figure 7; and FIGURE 9 is a sectional view of the rivetted joint on line 9-9 of Figure 8. ;19961 ;-8- ;01 The drawings show a fourth embodiment of this invention wherein:- ;FIGURE 10 is a perspective view of part of a first element for a stay; ;05 FIGURE 11 is a plan view of the rivetted joint in a stay including the first element shown in Figure 10; ;and ;FIGURE 12 is a sectional view of the rivetted joint on line 12-12 of Figure 11. ;10 The drawings show a fifth embodiment of this invention wherein:- ;FIGURE 13 is a perspective view of part of a first element for a stay; ;FIGURE 14 is a plan view of the rivetted joint in a 15 stay including the first element shown in Figure 13; ;and ;FIGURE 15 is a sectional view of the rivetted joint on line 15-15 of Figure 14. ;The drawings show a sixth embodiment of this 20 invention wherein:- ;FIGURE 16 is a perspective view of part of a first element for a stay; ;FIGURE 17 is a plan view of the rivetted joint in a stay including the first element shown in Figure 17; 25 and ;FIGURE 18 is a sectional view of the rivetted joint on line 18-18 of Figure 17. ;With reference to the drawings depicting the first embodiment, there is a base plate 1 being an extruded 30 section of aluminium or steel. Such base plate 1 has a flat surface 2 which would engage the sash or frame and be secured thereto by suitable means such as screws, rivets or other fasteners. The section includes edge flanges 3 and the surface 4 opposed to the base 35 surface 2 is also flat. ;19961 ;-9- ;The base plate is pierced by a hole 5 and concentric with the hole is a counter-sunk recess 6. The base surface of the recess 6 is formed with a series of radial serrations 7 that are raised or punched in the bottom of the recess. The serrations are of saw-tooth section and provide sharp edges radially spaced and circumferentially spaced within the recess 6. ;On the surface 4 opposed to the recess 6 there is an integral annular lip or collar 8 against which one face of an annular washer 10 abuts. The washer 10 may be of plastics material, or be a metal washer coated with a plastics material. ;The stay further includes another extruded section providing a link arm 11 pivotally connected to the base plate 1 through a rivet 12. The arm 11 has a shallow ;- • ;counter-bore 13 in which the washer 10 is seated and on the opposed side of the arm there is another counter-bore 14 and the arm is pierced by a'hole 15 concentric to the two counter-bores. ;The flat head 16 of a rivet 17 is seated in the , counter-bore 14 and is rotatable in said counter-bore. The rivet 17 is of the hollow or tubular type and the shank extends through the aligned holes 15 and 5 through the arm 11 and base plate 1. The washer 10 is carried on the shank of the rivet. ;The tail 18 of the rivet is rolled over under pressure so as to be forced down onto the serrations 7 to lock or secure the rivet tail against rotation relative to the base plate 2 and to complete the clinching of the rivet to hold the rivet in tension to connect the base plate 1 and the arm 11 together. The pressure applied to the rivet assembly during clinching may be determined in accordance with the degree, if ;199613 ;-10- ;01 any, of the friction to be left as a residual force within the joint after rivetting. ;As will now be understood, the tail of the rivet is compactly received in the recess 6 and permits the 05 face 2 of the base plate to be mounted flush against the sash or frame to which the stay is to be connected. Similarly, the head of the rivet is contained within the counter-bore in the link arm 11 and does not stand proud thereof. Accordingly, the length of the joint is 10 kept to a minimum, and due to the tail and the head of the rivet being housed within recesses, damage to the rivet in use due to external impact or on folding and unfolding of the stay is minimised. Furthermore, as the tail and head of the rivet are so housed, the risk 15 of detritus entering the clearance by the rivet shank is obviated. ;The washer 10 provides thrust faces for transmitting loads between the base plate and the link arm whilst also ensuring that the base plate and link 20 are are spaced apart sufficiently to prevent contact between adjacent faces on pivotal movement. ;The size and length of'the rivet can be varied and if desired, the rivet may be solid with the tail of a solid rivet being spun over to be forced into 25 engagement with the serrations of the recess. ;With reference to the second embodiment of this invention, there is provided a base plate 20 being an extruded section and this is pivotally connected through a rivet 21 to a link arm 22, this forming part 30 of a stay generally of the type as described with reference to the first embodiment. ;In this second embodiment, the base plate is formed with a series of radially extending serrations 23 which stand up from the surface 24 of the ;-11- ;199613 ;01 base plate 20. These raised serrations are punched or otherwise formed in the base plate 20 so as to leave a recess 25 of similar form on the other face of the base plate. ;05 A washer 26 is located on the shank of the rivet and extends between the base plate and the link arm. The head 27 of the rivet is flat and not received in a counter-bore in the arm but stands proud thereof. Similarly, the tail 28 of the rivet which is spun down 10 into engagement with the serrations 23 is not housed or received within any recess in the base plate. The rivet is shown of solid form, but can be a tubular or hollow rivet if desired. ;As in the first embodiment, the tail of the rivet 15 is located against rotation by the engagement with the serrations, and a simple construction is obtained. In a stay, clearances to provide a space between the clinched tail of the rivet and the head may be required. These are simple to provide by joggling or 20 kinking the base plate and/or the link arm, or by providing clearances in the other members relative to which the base plate and the link arm are either fixed or move. ;With reference to the third embodiment of this 25 invention, the stay comprises a base plate 30 of similar form to that of the first embodiment. The base plate has a hole for receiving the shank of a rivet 31 which extends through a hole in a link arm 32. The base plate 30 is provided with a recess 33 having a 30 flat annular botom but side edges which are serrated so that the plan view of the recess is star-like in outline. ;As previously explained, the tail of the rivet is rolled over into the recess and on such clinching the ;199613 ;-12- ;tail of the rivet is pressed into the serrations, and is non-rotatably confined with respect to the base plate. As also, previously explained, the base plate 32 is provided with a shallow collar 35 against which a washer 36 abuts, and the head 37 of the rivet is received in a counter-bore in the link arm. ;In this embodiment it is also possible to use a solid rivet instead of the hollow type shown. ;Other features of this embodiment may be deduced from the description previously given with reference to the first embodiment. ;With reference to the fourth embodiment, this is similar to that of the first and third embodiments previously described with the exception of the shape of the formation in the base plate 40 which is to receive the tail of the rivet 41. The recess 43 is of square shape in out-line and due to the non-circular shape prevents the tail of the rivet from rotating after clinching of the rivet to connect the link arm 42 to the base plate 40 with the washer 44 therebetween. ;With reference to the fifth embodiment, this is similar to that of the fourth embodiment just described, and the base plate 50 has a square shaped recess 51 into which the tail of a rivet 52 is clinched when the link arm 53 is connected to the base plate 50 with the intervening washer 54 on the shank of the rivet. In this case, the tail of the rivet is split into four end portions 55 and each of these is rolled into a respective corner of the square recess 51 on clinching. The splitting of the tail may be done as part of the clinching operation. ;With reference to the sixth embodiment, this follows from the last described embodiment and also provides for the rivet 60 to have a tail which is split ;-13- ;199613 ;01 into four portions 61 on clinching. However in this embodiment, the recess 62 in the base plate 63 is formed with four radially extending lobes, and each of the tail portions of the rivet is clinched so as to 05 engage within a respective lobe. As previously, the engagement of the tail in such lobes prevents the rivet rotating relative to the base plate 63 when the link arm 64 is turned relative to the base plate with the washer 65 therebetween. ;10 Various other types of formation to provide the keying or locking of the rivet tail on the base plate are envisaged and other constructions of multi-lobe formation are suitable. ;Additionally, other forms of serrations can be 15 provided and these may be irregular. ;In stays according to this invention, various different sections for the base plate and the link arm can be provided, and these are selected in accordance with the design and application of the stay. 20 Similarly, different arrangements for the direction of rivetting may be employed with the tail of the rivet being exposed on the front face of the link arm or other part of the stay. ;The rivet may be of any suitable material, and to 25 prevent corrosion, it may be coated or suitably treated. Preferably, the rivet is coated with a plastics material such as nylon. By providing such coating, then the shank of the rivet is protected against wear and damage from any contact with the base 30 plate and the link arm, and the risk of wear from the rotation of the head of the rivet is obviated. Other advantages which are outside the scope of this invention arise from such coating on the rivet, and for further details the reader is directed to our ;35 New Zealand Patent Specification No. 198,257 ;'' V K ;^ which describes and claims the use of a plastics coated rivet in a friction window stay. ;' ;V ;v*

Claims

199613 01 -14- WHAT/t/WE CLAIM 15:--Claijua. oo CO to Q UJ > UJ a UJ a:

1. A stay of the kind specified having first and second elements pivotally connected together by a 05 rivet, wherein the first and second elements are spaced apart by a washer and the rivet extends through the elements and the washer with the head of the rivet engaging the face of the first element remote from the washer, and the tail of the rivet being clinched on the 10 face of the second element remote from the washer, the second element having a formation in said face into which the tail of the rivet is clinched under pressure to prevent rotation of the rivet relative to the second element. 15

2. A stay according to claim 1 wherein the clinching pressure applied to the rivet is sufficient to provide frictional restraint within the joint.

3. A stay according to claim 1 or claim 2 wherein the formation is recessed in the face of the second 20 element by being formed in a counter-bore or countersink so that the clinched tail of the rivet is contained within such recess and does not stand proud of the face of the second element.

4. A stay according to claim 3 wherein the formation 25 is in the form of serrations formed in the bottom or on the internal wall of the recess.

5. A stay according to claim 4 wherein the serrations are radial or radially spaced with respect to the axis of the rivet. 30

6. A stay according to claim 4 or claim 5 wherein the serrations have sections or configurations selected from saw-toothed, crenate, dentate or saw-like.

7. A stay according to claim 1 or claim 2 wherein the formation comprises a non-circular wall edge of a 35 recess in the second stay element. O C; .< 1 "2 //O I J -15- i - CO ©X Q " LU CO > hi UJ LU u_ O < a. ro i LU a: M 2 01

8. A stay according to claim 7 wherein the formation comprises a recess having at least two lobes into which the tail of the rivet is clinched.

9. A stay according to claim 7 wherein the recess is 05 of square form into which the tail is clinched.

10. A stay according to claim 1 or claim 2 wherein the formation is raised, projects or stands proud of said face of the second element.

11. A stay according to claim 10 wherein the raised 10 formation is in the form of serrations, teeth or crenulations extending radially with respect to the rivet axis.

12. A stay according to any one of the preceding claims wherein the formation is punched or raised in 15 the operation for making the rivet hole in the stay part, such as by punching or piercing.

13. A stay according to any one of the preceding claims wherein the washer is of plastics material, preferably a low friction material such as acetal or 2 0 nylon.

14. A stay according to any one of the preceding claims wherein the washer is a plastics coated metal washer.

15. A stay according to any orie of the preceding 2 5 claims wherein the washer is a flat annulus.

16. A stay according to any one of the preceding claims wherein the thrust face of the second element contacting the washer is provided by an annular recess or lip concentric with the rivet axis. 30

17. A stay according to claim 16 wherein such recess or lip is formed in the pressing or piercing operation applied to the stay element.

18. A stay according to any one of the preceding claims wherein a recess is provided in the first stay 35 element for receiving the washer. 1 9 96 1 -16-

19. A stay according to any one of the preceding claims wherein the first stay element has a counter-bore receiving the head of the rivet.

20. A stay according to any one of the preceding claims wherein the rivet has a low friction surface.

21. A stay according to claim 20 wherein the surface is a plastics coating.

22. A stay according to any one of the preceding claims wherein the rivet is hollow and the tail is rolled or turned during clinching.

23. A stay according to any one of the preceding claims wherein the first and second elements are selected from the combinations of stay parts being:-an arm and a plate; two link parts; an arm and a shoe; a plate and a link; a bracket and an arm.

24. A stay of the kind specified and having a rivetted joint substantially as hereinbefore described with reference to the drawings of Figures 1, 2 and 3.

25. A stay of the kind specified and having a rivetted joint substantially as hereinbefore described with reference to the drawings of Figures 4, 5 and 6.

26. A stay of the kind specified and having a rivetted joint substantially as hereinbefore described with reference to the drawings of Figures 7, 8 and 9.

27. A stay of the kind specified and having a rivetted joint substantially as hereinbefore described with reference to the drawings of Figures 10, 11 and 12.

28. A stay of the kind specified and having a rivetted joint substantially as hereinbefore described with reference to the drawings of Figures 13, 14 and 15.

29. A stay of the kind specified and having a rivetted joint substantially as hereinbefore described with reference to the drawings of Figures 16, 17 and 18.