GB2182090A

GB2182090A - A pipe clamp

Info

Publication number: GB2182090A
Application number: GB08526608A
Authority: GB
Inventors: Franz Muller
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-10-06
Filing date: 1985-10-29
Publication date: 1987-05-07
Also published as: DE3436710C2; DE3436710A1; ATA287485A; FR2571465B1; NL193197C; NL8502722A; GB2182090B; AT391747B; FR2571465A1; CH668817A5; GB8526608D0; NL193197B

Abstract

The pipe clamp comprises a clamp strap with at least one opening. On one side of the opening a tightening screw (26) is pivotably mounted together with a nut (30). On the other side of the opening the screw head can be engaged in a slot (36) in a projection (22). The slot (36) is narrower than the smallest cross-sectional dimension of the screw head and at the radially inner end undergoes a transition into a widened portion which is situated in the strap (12) and through which the screw head can pass when being engaged in the slot (36). After engagement of the screw head, the latter is turned by means of a tool so as to close the pipe clamp tightly. <IMAGE>

Description

SPECIFICATION A pipe clamp This invention relatesto pipe clamps ofthetype in which an annular strap has an opening bounded by radially extending flanges fastened with a screw.

A pipe clamp ofthistype is disclosed in DE-OS 33 46 423. Here a nut forming the screw base is engaged, with a hookformedthereon on its radially inner side relative to the pipe clamp axis, pivotably in a lug-typeflange on the pipe clamp strap. The other flange has a radially outwardly open slot into which the screw head can be inserted. However, this connection is notsuitablefortaking up a relatively high tightening force, since the screw base is attached at its small hookand,upon deformation ofthepipe clamp, the screw head slips radially out ofthe slot under load.

Because of the possibility ofthetightening screw being pivoted radially outwards from the normal position, a pipe clamp fastener of the above-mentioned type also cannot be devised with a slot having a radially inwardly arranged opening in accordance with DE-OS 33 08 459. Moreover, the weak point of the hook loaded by the tightening force would still be present atthe base of the tightening screw.

The invention is therefore based on the object of devising a pipe clamp of the initially mentioned type, which combinesthe ability to accommodate high loads with simple installation.

According to the present invention there is disclosed a pipe clamp having afastening elementfor use in fastening the clamp to a wall or ceiling orthe like and comprising a substantially annular strap having at least one opening bounded by radially projecting flanges, a screw and co-operating screwthreaded base for fastening the flanges together, wherein the base is mounted on oneflange for pivotal movement aboutthefree end oftheflange and the screw extends through a radial slot in the second flange having an enlarged aperture at its radially inner end andthrough a hole in the first flange which is enlarged with respect tothescrewshanktoaccommodate pivotal movement of the screw and base between a first position in which the screw is normal to the flanges and a second position in which the screw is inclined to the normal wfththe screw head extending through the enlarged slot aperture.

Preferably the slot extends from the second flange i:ntothe strap and the aperture is formed in the strap adjacenttotheshoulderformedatthejunction ofthe second flange and the strap.

Preferablythe screw base is formed by a nut which is retained by a tongue mounted on the free end ofthe firstflange. Conveniently the nut is formed by a bent-over extension of the firstflange provided with a threaded hole.

Alternatively the nut may be formed as a disc provided with a threaded sleeve or a threaded hole and a further hole, which disc is retained captively by a tongue inserted through the further hole and bent over.

Conveniently the disc is so bent over at the edge that in the closed position of the pipe clamp it encloses the edge surfaces of both flanges.

The invention offers the advantage that the tighten- ing screw has at both ends a secure support on which high loads can be imposed but can still be prepared for engagement by a simple pivotal movement. In this case it is of no importance whetherthe nut is situated on the pivot mounting side, i.e. atthe base end ofthe tightening screw, orforms its head. However, the first alternative is preferred because then the screw head can be provided with a longitudinal slot, cross-slot or hexagon and may beturned using a conventional screw driver or socket wrench, optionally motor driven,whereasthescrewshankextendingthrough the base faces towards the fastening side of the pipe clamp,where it poses nodangerofinjury.

Furthermore, the pipe clamp fastener proposed has the advantage that, during installation, a nutforming the screw base exerts a tilting moment on the tightening screw in the direction in which the screw hasto be inserted into the slot.

According to a further aspect of the present invention there is disclosed a pipe clamp having a fastening elementforuseinfasteningtheclamptoa wall orceiling orthe like and comprising a substantial lyannularstraphaving at least one discontinuity bounded by radially projecting flanges, a screw and co-operating screwthreaded base forfastening the flanges together, wherein the base is a hinge pin having a threaded radial bore, being mounted on one flange for rotation movement relative to the strap and wherein the screw extends through a radial slot in the second flange having an enlarged aperture at its radially inner end and through a hole in the first flange which is enlarged with respect to the screw shankto accommodate pivotal movement ofthe screw and base between a first position in which the screw is normal to the flanges and a second position in which the screw is inclined to the normal with the screw head extending through the enlarged slot aperture.

In an advantageous development of the invention, the screw head is prevented from accidentally slipping out of the slot in longitudinal direction inthattheslo.t extends beyond the corner between a projecting flange and the strap into the latter and adjacent thereto has the enlarged orwidened portion. In this way, atthe transition between the flange and the clamp strap a step-like shoulder is formed which retains the screw head in the slot.Of course, instead of a step-like shoulderformed inthisway it is also possible to provide an impressed or attached shoulder on the surface of the slotted flange, which may be situated radially close to the screw head or also below it and then engages, forexample, in an annular groove inthe underside ofthe screw head. In afurther advantageous development ofthe invention, to facilitate the passage of the screw head over the step-like shoulder, upon dismounting the clamp, and to disengage it radially inwards from the flange, it is possible to provide on that surface of the projection against which the screw head abuts a raised portion or recess which constitutes a tool seating for levering the screw head towards the widened portion ofthe slot and/or for urging it with a tool, without danger of slipping, in the closing direction of the opening against the flange.

In a further modification of the invention, the slot in which the screw head engages could be provided in a tongue connected articulatedly to the strap, instead of in a flange rigidly connected to the strap. Further variants of embodiment are provided by arranging the widened portion ofthe slot, in which the screw head engages,wholly or partly in the projection, irrespective ofwhetherthe latter is in the form of a flange or a tongue pivotally mounted on the strap. In another similarembodiment,thewidened portion does not adjoin exactly radially the slot in which the screw head engages butthe centre of the widened portion lies axially offset relative to the centre ofthe slot.

It is not absolutely necessaryto the invention forthe nutto be securely connected to a flange disposed opposite the slot with a widened portion so that it does not rotate therewith when the tightening screw is tightened byturning the screw head. However, the nut should be prevented from rotating preferably at least when the screw head has been engaged in the slot in the projection and a tensile force is then acting on the tightening screw. In a simple embodimentofthe invention, this can be achieved in that, when applied againstthe flange, the nut engages with at least one eccentric projection over the edge of the flange or engages in a hole or depression in the flange.

The deformability or mobility ofthe clamp strap is of considerable importance with respect of the ease and rapidity of installation. Therefore, in a preferred embodiment of the invention, one-piece clamp straps of such strength that they cannot be readily bent are provided, which have at least one predetermined bending pointwhich, for example, may be disposed near one ofthe flanges oron the diametrically opposed side. In an embodiment according to the invention, two-piece clamp straps preferably have on the side oppositetheflanges a connection with radial play.According to the preferred practical embodiment,the nutforthetightening screw atthe opening ofthe pipe clamp comprises a discorwhasher provided with a threaded sleeve or a threaded hole and a further hole, which is retained in captive manner bya tongue inserted through the further hole and then bent over, while the connection on the opposite side of the pipe clampcomprisesasecond tightening screw extending through a pair of flanges, in which case the flange disposed on the same strap part as the projection with the slot and widened portion is provided with a hole which is longer in radial direction than the diameter of the screw shank but narrower than the diameter of the screw head; moreover, this connection on side opposite the opening ofthe pipe clamp is of similar construction to the connection at the opening itself. Additionally, it is also possible, in a two-piece pipe clam p, for both connection points to be formed with engageable screw connections in accord ance with the invention.

Finally, as a further preferred feature in develop ment ofthe invention, it is proposed that in those cases in which the widened portion ofthe slot, into which the screw head isto engage, is dispose in the strap, the end edge ofthe widened portion is bent over radially inwards. This bent-over end edge, which is in the shape of a radially inward facing short tongue, offers two advantages. It ensures that a sound absorbing rubber insert placed in the pipe clamp is prevented from slipping at the widened portion ofthe slot and thereby rendering installation more difficult.

Moreover, with very simple means it is thus possible to prevent, during installation, the end edge from engaging in a transverse slot in thescrew head and obstructing the further pivotal movement necessary forthe engagement of the tightening screw.

The invention will now be explained in more detail below with reference to oneembodimentillustrated byway of example in the drawings, wherein Figure 1 shows a side view of a pipe clam pin the closed position; Figure 2 shows the pipe clamp according too Hgure 1 in the state during installation; Figure 3 shows a side view of a pipe clamp according to Figure 1 displaced th roug h 909 The pipe clamp shown in the drawing has a strap consisting of two parts 10 and 12. Afastening element 14, in this embodiment in the form of a threaded nut, is welded to the part 10. The pipe clamp can thereby be fastened to a wall or ceiling.

Attheir ends, both pipe clamp parts 10 and 12 have flanges designated 16, 18 and 20,22 respectively. The connection between the two parts 10,12 is effected by means of tightening screws 24,26 and nuts 28,30. The tightening screws 24,26 are fitted th rough radially aligned slots in the flanges 16, 18,20. In the loose condition according to Figure 2, these slots provide radial play between the two pipe clamp parts 10,12 and they enable the tightening screws to adopt an inclined position relative to the flanges. To enable this inclined position shown in Figure 2to be attained, the nuts 28,30, which in this embodiment are in the form of relatively flat sheet-metal washers, are held pivotably in each case only atthe free of the flanges 16,18 my means of respective tongues 32 and 34 mounted thereon.The tongues 32,34each extend through a hole in the nuts 28 and 30 respectively and attheir ends are so deformed towards the clamp strap that the nuts can in fact pivot to a limited extent but can not be removed from the flanges. In this way the nuts 28,30 are retained in captive fashion on the pipe clamp.

Anotherfeature ofthe nuts 28,30 lies in thefactthat in contourthey match the contour oftheflanges and are so bent over at the edge that they overlap the edge.

surfaces of the flanges. Firstly, the non-rotatable location of the nuts 28,30 on the flanges is thereby ensured and, secondly, lateral rounded overlapping of the sometimes shape edges of the flanges is achieved.

Finally, with suitable design of the bent-over edgeof the nuts, support could also be prnvidedforascrew driver, for example, with which to exert presure againstthe screw head or flange 22.

As evident from Figure 1, in the instaUecl position the free ends ofthetightening screws24,26, which project to a considerable extent, are situated onthe same side of the flange as the fastening element 14, i.e. they pointtowardsthe wall or ceiling, whereasthe screw heads arefreelyaccessiblefromthefrontor from below.

In orderto be ableto install the pipe clamp in a particularly simple manner, a slot 36 is provided in one oftheflanges against which a screw head abuts, in this case in the flange 22, which slot like the slots in the otherflanges is slightly wider than the screw shank and narrowerthan the screw head. However, in contrast to the holes in the other flanges, the slot 36 extends into the clamp strap, whereupon it undergoes atransition into a widened portion 38 which is sòniewhat broader and higherthan the screw head.

The transition between the narrower portion 36 and the broader portion 38 ofthe recess in the flange 22 and the adjacentzone ofthe clampstrap is not situated directly at the transition between the flange and clamp strap, but is displaced slightly into the clamp strap, but is displaced slightly into the clamp strap so tharastep-like shoulder is provided on this latter so as to: prevent the head ofthetightening screw 26, after being inserted through the hole portion 38 and after abutting flatly against the flange 22, from being able to slipback radially inwards out ofthe flange 22.Moreover, to open the pipe clamp, it is necessaryforthe head ofthetightening screw 26 to be raised from the flange 22to such an extent that it can be guided out radially inwards through the wider portion 38 of the hole spaced apartfrom the flange 22.

Of course, the invention is not restricted to the example of embodimentdescribed and illustrated in the foregoing. It is suitable both for one-piece pipe clamps and those consisting of more than two parts.

Instead oftightening screws with atransverse slot in the screw head for use with a simple screw driver, it is also possible to use screws with different heads, e.g.

cross-slotted screws or those with external or internal hexagons.

In a variation from the preferred form of the holes 36,38 with a transition from the narrower portion 36 into the broader portion 38: at a distance from the flange 22, the arrangement could also be such thatthe broader portion 38 of the recess extends at least partly into the flange 22. Upon installation, the two clamp parts 10, 12 would not needto be mutually displaced to such an extent and the head of the tightening screw 26 would not require such a large clearance between the pipe and the clamp strap so that it can be inserted through the broader portion 38 of the hole.

The nuts 28,30 could be of a simpler shape than that shown and would not haveto be retained in captive fashion by tongues 32,34. In practice, immediately after engagement in the hole 36,38 in the flange 22, a tensile force acts on the tightening screw 26 so as to draw the nut 3Q against the flange 18.To securethe nut 30 against rotation, upon subsequently tightening the tightening serew 26, it is thus only necessary for a non-circular surface of the nut 30to abut against a prnjectianoftheflange 18 or, conversely, for a projection onthe nut 30 to abut against an edge surfaceofthetongue 18 or other non-circularsurface.

Figure 2 shows that upon bringing together the two clamp parts 10,12 during installation firstlythe region onthe flange 22 abuts against the head of the tighteningscrew 26. Therefore, installation isfacili iatedifthescrnw head and/or the pipe clamp, in the vicinity ofthe transition between the flange 22 and the clamp strap, are inclined in such awaythataforce is exerted on the tightening screw 26 which urges its head radially inwards.This results in bracing of the nut 30 with the flange 18, whereby a tilting moment is exerted on the tightening screw 26, which promptly urges the screw head radially outwards through the widened portion 38 of the hole when the screw head reaches this broader hole portion 38 upon pressing togetherthe clamp parts.

Another possible variation provides forthe nuts 28, 30 to be formed in one piece with the flanges 16 and 18 respectively, advantageously only relatively narrow tongues ortabs also being provided in this case between the flanges and the nuts in orderto ensure the pivoting action of the nuts evident from Figure 2.

The invention is particularly suitable for pipe clamps with sound-absorbing rubber inserts, because in this case during installation more space is availableforthe head of thetightening screw 26 in the clearance between the clamp strap and the pipe. With a view to preventing the rubberinsertfrom slipping atthe widened portion 38 of the slot 36 it is possible, according to Figure 1,forthe end edge of the widened poriton 38 to be bent over radially inwards to form a small tongue 40.

Finally, reference is made again to a possible embodiment indicated in Figure 2, wherein the flange 22 is formed with a raised edge 42 extending over its periphery. Therefore, to facilitate engagement of the tightening screw 26, a tool can be pressed against the flange 22 without any danger of the tool slipping off of the flange 22.

Diverging from the example of embodiment shown, anothervariantofthe invention lies inthatthe pipe clamp is not connected to a fastening element 14 but, for example, by means of the tightening screw 26 is suspended from a supporting member such as an eye.

In this case, the tightening screw 26 is firstly passed with its head through the eye, then engaged in the slot 36 in the flange 22 and, finally, tightened by means of a screw driver.

Claims

1. A pipe clamp having a fastening element for use in fastening the clamp to a wall or ceiling orthe like and comprising a substantially annular strap having at least one opening bounded by radially projecting flanges, a screw and co-operating screwthreaded base forfastening the flanges together, wherein the base is mounted on one flange for pivotal movement aboutthe free end of the flange and the screw extends through a radial slot in the second flange having an enlarged aperture at its radially inner end and through a hole in the first flange which is enlarged with respect to the screw shank to accommodate pivotal movement ofthe screw and base between a first position in which the screw is normal to the flanges and a second position in which the screw is inclined to the normal with the screw head extending through the enlarged slot aperture.

2. A pipe clamp as claimed in Claim 1 wherein the slot extends from the second flange into the strap and the opening is formed in the strap adjacent to the shoulderformed atthejunction of the second flange and the strap.

3. A pipe clamp as claimed in Claim 1 or Claim 2, wherein the screw base is formed by a nut which is retained by a tongue mounted onthefree end ofthe first flange.

4. A pipe clamp as claimed in Claim 3, wherein the nut is formed by a bent-over extension of the first flange provided with a threaded hole.

5. A pipe clamp as claimed in Claim 3, wherein the nut is formed as a disc provided with a threaded sleeve ora threaded hole and a further hole, which disc is retained captively by a tongue inserted through the further hole and bent over.

6. A pipe clamp as claimed in Claim 5, wherein the disc is so bent over atthe edge that in the closed position ofthe pipe clamp itenclosesthe edge surfaces of both flanges.

7. A pipe clamp having a fastening element for use in fastening the clamp to awall orceiling orthe like and comprising a substantially annular strap having at least one discontinuity bounded by radially projecting flanges, a screw and co-operating screwthreaded base forfastening the flanges together, wherein the base is a hinge pin having a threaded radial bore, being mounted on one flange for rotation movement relative to the strap and wherein the screw extends through a radial slot in the second flange having an enlarged aperture at its radially inner end and through a hole in the firstflange which is enlarged with respect to the screw shank to accommodate pivotal movement of the screw and base between a first position in which the screw is normal to the flanges and a second position in which the screw is inclined to the normal with the screw head extending through the enlarged slot aperture.

8. A pipe clamp as claimed in any one of Claims 1 to 7 wherein on that surface of the flange against which the screw head abuts a raised portion or recess is arranged which constitutes a tool seating for levering the screw head towards the opening of the slot and/orfor urging it with a tool in the closing direction ofthe opening againstthe flange.

9. A pipe clamp as claimed in any of the preceding claims, comprising a one-piece strap with at least one predetermined bending point.

10. A pipe clamp as claimed in any one of Claims 1 to 8, comprising a two-piece strap the connection of which is formed with radial play on the side opposite the opening.

11. A pipe clamp as claimed in Claim 10, wherein the connection comprises a second tightening screw extendingthrough a pair offlanges, in which case the flange disposed on the same strap part as the flange with the slot is provided with a hole which is longer in radial direction than the diameter of the screw shank but narrowerthan the diameter of the screw head and, moreover, this connection is of similar construction to the connection atthe opening ofthe pipe clamp.

12. A pipe clamp as claimed in any of the preceding claims, having an oblique surface on the screw head and/or its abutment surface on the flange, which under mutual counter pressure upon closing the pipe clamp presses the screw head radially inwards.

13. A pipe clamp as claimed in any of the preceding claims with an end edge of the widened portion of the slot disposed in the strap, wherein the end edge of the widened portion is bent over radially inwards.

14. A pipe clamp substantially as hereinbefore described with reference to and as shown in Figures 1 to 3 ofthe accompanying drawings.

Newclaimsoramendmentstoclaimsfiled on 18/10/86.

Superseded claims 1-14.

New or amended claims: 1-16.

1. A pipe clamp having a fastening elementfor use in fastening the clamp to a wall or being orthe like and comprising a substantially annularstrap having at least one opening bounded by radially projecting flanges, a screw and co-operating screw threaded base forfastening the flanges together, wherein the base is mounted on one flange for pivotal movement and the screw extends through a radial slot iathe second flange having an enlarged aperture at its radially inner end and through a hole in the firstflange which is enlarged with respect to the screw shankto accommodate pivotal movement of the screw and base between a first position in which the screw is normal to the flanges and a second position in which the screw is inclined to the normal with the screw head extending through the enlarged slot aperture.

2. A pipe clamp as claimed in claim 1 whereinthe second flange comprises a tongue like member connected articulatedlyto the strap.

3. A pipe clamp as claimed in any preceding claim wherein the base is pivotally mounted about an axis located at a greater radius than the screw so asto be adjacenttothefree end oftheflange.

4. A pipe clamp as claimed in any preceding claim wherein the slot extends from the second flange into the strap and the opening is formed in the strap adjacentto the shoulderformed atthe junction of the second flange and the strap.

5. A pipe clamp as claimed in any preceding Claim wherein the screw base is formed by a nutwhich is retained by a tongue mounted on thefree end ofthe first flange.

6. A pipe clamp as claimed in Claim 5,whereinthe nut is formed by a bent-over extension of the first flange provided with athreaded hole.

7. A pipe clamp as claimed in Claim 5, wherein the nut is formed as a disc provided with athreaded sleeve or a threaded hole and a further hole, which disc is retained captively by a tongue inserted through the further hole and bent over.

8. A pipe clamp as claimed in Claim 7, wher & .nthe disc is so bent over atthe edge that in the closed position of the pipe clamp it encloses the edge surfaces of both flanges.

9. A pipe clamp having a fastening elemen;tforuse infasteningtheclamptoawall orceilingorthelike and comprising a substantially annular strap having at least one discontinuity bounded by radially projecting flanges, a screw and co-operating screwthreaded base forfastening the flangestoge#her, wherein the base is a hinge pin having threaded radial bore, being mounted on oneflangeforrotation movement relative to the strap and wherein the screw extends through a radial slot in the second flange having an enlarged aperture at its radially inner end and through a hole in the first flange which is enlarged with respect to the screw shank to accommodate pivotal movement ofthe screw and base between a first position in which the screw is normal to the flanges and a second position in which the screw is inclined to the normal with the screw head extending through the enlarged slot aperture.

10. A pipe clamp as claimed in any one of Claims 1 to 8 wherein on that surface of the flange against which the screw head abuts a raised portion or recess is arranged which constitutes a tool seating for levering the screw head towards the opening ofthe slotand/orfor urging it with a tool in the closing direction of the opening against the flange.

11. A pipe clamp as claimed inanyofthe preceding claims, comprising a one-piece strap with at least one predetermined bending point.

12. A pipe clamp as claimed in any one of Claims 1 to 10, comprising a two-piece strap the connection of which is formed with radial play on the side opposite the opening.

TS. A pipe clamp as claimed in Claim 12, wherein the connection comprises a second tightening screw extending through a pair offlanges, in which case the flange disposed on the same strap part as the flange with the slot is provided with a hole which is longer in radial directionthanthe diameter ofthe screw shank but narrowerthan the diameter ofthe screw head and, moreover, this connection is ofsimilarconstruction to the connection atthe opening ofthe pipe clamp.

14. Apipe clamp as claimed in any ofthe preceding claims, having an oblique surface on the screw head and/orits abutment surface on the flange, which under mutual counter pressure upon closing the pipe clamp pressesthe screwhead radially inwards.

15. Apipeclampasclaimed inanyofthe preceding claimswith an end edge of the widened portion of the slot disposed in the strap, wherein the end edge ofthewidened portion is bent over radially inwards.

16. A pipe ctarnp substantially as herein before described with referenceto and as shown in Figures 1 to 3 oftheacconspanying drawings.