DE29612482U1 - Compression fitting for elongated bodies with a union nut - Google Patents

Description

PATENT AND LAW FIRM: : : · : : fcatentarivfäßDipl.-Ing. H. Schmitt
C ₁ ^iTTTi &tgr;&tgr;&pgr;-,&ggr;&ggr;, ,,&Agr;&idiagr;&iacgr;&eegr;&tgr;&tgr;&eegr;&ogr;&pgr;&Lgr;&eegr;&tgr;&tgr;-'&iacgr;'" ** Patent Attorney Dlpl.-Ing. W. Maucher
SCHMITT, MAUCHER & BORJES Patent and Litigation Attorney H. Börjes-Pestalozza

Anton Hummel Verwaltungs GmbH Mozartstrasse 2 79183 Waldkirch

Dreikönigstr. 13 D-79102 Freiburg i. Br.

Telephone (0761) 706773 Fax (0761) 706776 Telex 7 72 815 SMPAT D

1 7. JUL! ms Mr/hae/be

Clamp fitting for elongated bodies
with a union nut

The invention relates to a clamp screw connection for lines, pipes, heating pipes, hoses or for cables or other elongated bodies, in particular made of plastic, with a receiving sleeve having a thread and a counter sleeve or union nut that can be screwed onto it and with a clamp insert, clamp ring or clamp part that can be pressed onto the pipe or similar elongated body by the screw connection and that has slots that run along its axial extent and are open at least on one end face, the clamp part being acted upon or overlapped by at least one ring-like, tapered pressure surface on one of its end faces and, when the thread of the counter sleeve or union nut is tightened, being deformable and pressed against the pipe or elongated body with a tapered shape, for example by means of a cone or rounding, reducing the width of the slots, and in the case of an elongated body that is hollow on the inside, in particular a support sleeve in the clamping area in the interior of the elongated body or pipe intervenes.

Such a clamping screw connection is known for example from DE 44

03 702 C2 and has proven itself. In this case, the clamping part is a separately insertable clamping ring. However, it is also possible for the clamping part to be connected to the receiving sleeve.
5

If such a known compression fitting is to be used on an approximately vertically arranged elongated body or pipe, particularly in its upper area, the problem arises during assembly that the counter sleeve or union nut, which can be moved over the elongated body, particularly together with the clamping insert, is pushed from the application or clamping point through the

^ Gravity slides downwards if no precautions are taken, so that assembly is made more difficult. The fitter must at least use both hands to secure the compression fitting, otherwise the union nut will slip away from the clamping point.

The task is therefore to create a clamping screw connection of the type mentioned at the beginning, in which the assembly is also 0 simplified with an obliquely or vertically arranged elongated body and in particular with a clamping point arranged in its upper area.

fe The solution to this problem essentially consists in the fact that the 5 counter sleeve or union nut and/or the clamping insert or the like connected to it at least in the axial direction and/or a holding body or retaining ring connected to the counter sleeve or union nut or the clamping insert or the like at least in the axial direction engages frictionally or 0 self-adhesively and displaceably on the outside of the elongated body.

Such an arrangement makes it possible to position the counter sleeve or union nut with the clamping insert and a holding body or retaining ring provided in a position suitable for assembly.

to move it to a favorable position on the downward-facing elongated body, where it automatically remains even when arranged vertically due to the frictional connection, i.e. it can be arranged for assembly directly in the area of the receiving sleeve, with which it is then finally brought together and screwed. This allows a fitter to grasp the union nut in the correct position with one hand and screw it onto its counter thread, without first having to move it upwards from a possibly great depth to the place of assembly.

In the following, instead of "counter sleeve or union nut", we will only refer to "union nut", although a counter sleeve is also meant in the same way, which can be screwed into an internal thread of the receiving sleeve with an external thread.

It can be advantageous if the union nut or the clamping insert or the like contains a sealing ring which, in addition to its sealing function in the position of use, acts as a retaining ring and acts frictionally on the surface of the elongated body before screwing. In such an embodiment, a sealing ring thus has a dual function because, on the one hand, it creates the desired seal in the position of use, but beforehand it ensures that the union nut

^ is automatically held close to its mounting position,

even if the elongated body is arranged obliquely or vertically.

Another or additional embodiment of the invention of very considerable advantageous significance can provide that the 0 union nut and/or the clamping insert and/or the holding body or retaining ring has at least one radially inwardly directed projection that acts on the elongated body in a frictional manner. 5 As a result, the frictional engagement with the surface of the elongated body or pipe can be expediently achieved 5 taking into account possible manufacturing tolerances over the

This can be achieved by using a clamping insert which has a certain flexibility, i.e. when pushed onto an elongated body it may be slightly expanded by the projections and can therefore be pressed automatically onto the elongated body with friction.

It is particularly advantageous if the projection(s) on the clamping insert protrude(s) inwards into the inner opening of the clamping insert by approximately the amount of radial play relative to the elongated body and/or by the amount of radial expandability of the clamping insert within the union nut before it is screwed on or less and in particular is/are not or only slightly flexible.

In this case, the frictional force is caused almost exclusively by the elasticity of the clamping insert, so that the clamping insert and its elasticity are used before the actual clamping process to generate a frictional force via the projections mentioned, by means of which the union nut with the clamping insert can be temporarily held in a desired pre-assembly position. The clamping insert is slightly expanded within the union nut via the projection(s) due to the play present there, so that the corresponding restoring force can generate the frictional connection.

If the relatively short projections themselves are not or only slightly flexible, they can also later be connected in a practically form-fitting manner during clamping with an elongated body made of a somewhat flexible material, for example a plastic tube, because they can then be pressed into its surface 0, so that an additional function, namely a better connection, can be achieved even in the position of use by such a projection.

A modified embodiment can provide that the projection 5 is elastically,

This also allows any manufacturing tolerances to be taken into account and the friction force can be largely predetermined by the shape and material of the projection(s).
5

A further design of great value is possible, which is particularly applicable to compression fittings with a counter sleeve or union nut and a clamping insert for gripping elongated bodies of different nominal diameters and consists in the radial dimension of the bendable projection being larger than the difference between the different radii of the

_ is the elongated body to be gripped. In this way, an elongated body with the smallest nominal diameter of the compression fitting is frictionally engaged and held by the inwardly projecting projection, while an elongated body with a larger nominal diameter of the same cable fitting bends this projection when it is plugged on and pushed in and is thus also frictionally secured.

0 An expedient and practical embodiment of the invention can consist in that on the inner circumference of the passage opening of the union nut or the like and/or the clamping insert and/or the holding body or retaining ring several radially inward

ml directed projections or an annular circumferential, approximately lip-shaped projection, in particular with radial-axial slots in the region of the slots of the clamping insert, are provided.

As a result, the friction forces are distributed practically evenly around the circumference of the elongated body and the union nut or counter sleeve is at least largely centered in the pre-assembly and holding position initially assumed at 0 even before its final assembly, while only a projection would lead to a slightly eccentric mounting relative to the elongated body.

It is advisable if the radially inserted into the inner cross section of the union nut, the clamping insert or the retaining ring

protruding projections are designed as flat tongues in the axial direction, which taper in particular in the radial direction. This means that the flexibility of the projection or projections increases towards their radially inner end and thus towards the middle of the cable gland, so that when an elongated body of medium or smaller nominal diameter is inserted, the entire tongue-shaped projection does not have to give way, but only as much of it gives way as the dimensions of the elongated body require, while a part of the projection that remains undeformed contributes to generating the desired friction force.

™ It is advantageous if the projection(s) is/are elastically bendable, in particular made of an elastically flexible plastic and is/are preferably connected in one piece with the clamping part, clamping insert or union nut. When the clamping screw connection is loosened, the projections can thus return to their original position. This design is particularly advantageous when arranged on a clamping insert, because the clamping insert is also expediently made of elastically flexible plastic in order to produce the corresponding clamping force under the pressure force of the union nut. If the clamping insert is manufactured in one piece with the frictional projections, these are then

— therefore automatically made of the same elastically flexible material &Iacgr;2 5 as the clamping insert.

The projection(s) can be arranged near one of the front sides of the clamping insert, in particular near the front side facing the thread. This can make it easier to attach 0 to the elongated body; because when attaching from the front side of the elongated body to be fixed, the latter is then first partially inserted into the clamping insert or the clamping insert is partially pulled over the end of the elongated body before the projections come into contact with this front side and are then deformed when further attached.

In this way, a certain amount of guidance of the insertion movement can be achieved by the clamping insert.

Examples of embodiments of the invention are described in more detail below with reference to the drawing. It shows, in a partially schematic representation:

Fig.l a compression fitting, partially in longitudinal section for a pipe, which is not yet fully assembled and in which a support sleeve is attached to the

front side of the pipe and into this

^ engages and a receiving sleeve in a hole

is screwed in, with which a union nut containing a clamping insert can be screwed to secure the pipe, which union nut despite a

vertical arrangement of the pipe near the installation point is held frictionally by projections on the clamping insert,

0 Fig.2 on an enlarged scale the detail marked in Fig.l A with a section through the clamping insert and a tongue-shaped projection provided thereon, which is pressed against the outer wall of the pipe and is thereby elastically deformed ^,

Fig. 3 shows the longitudinal section of the clamping insert according to Fig. 2 with the projection not deformed,

Fig. 4 is a plan view of a clamping insert with its

0 inner circumference distributed, narrow, tongue-shaped

Projections,

Fig. 5 is a plan view of a clamping insert corresponding to Fig. 4, in which a substantially circumferential lip-shaped projection is provided, which in the area

the axial-radial slots of the clamping insert are each interrupted by radial slots,

Fig. 6 partly in side view and partly in longitudinal section a modified embodiment in which the

union nut has projections formed integrally on its inlet opening and deformed by the pipe or similar elongated body,

Fig.7 shows on an enlarged scale the detail marked B in Fig.6 with a

fe and elastically deformed projection of the exit opening

the union nut,

Fig.8 again a partially longitudinal section

Side view of a union nut which, in addition to a conventional clamping insert, contains a retaining ring inside which is connected to the union nut in the axial direction and with its

0 Inner circumference or projections provided there rub

fits snugly against an elongated body,

Fig. 9 shows a modified embodiment in which

fc as a retaining ring arranged in the clamping insert

Sealing ring is provided, which with its inner opening

frictionally engages the outside of the elongated body and holds the union nut - as in the other embodiments - in a preselected position,
30

Fig.10 is a representation of a modified clamping screw connection for a pipe, corresponding to Fig. 1, wherein relatively short, rigid projections directed radially inwards are provided on the clamping insert,

5 which initially expands elastically when plugged in

of the clamping insert,

Fig. 11 shows on an enlarged scale the detail marked C in Fig. 10 with a relatively short, non-deformed projection resting on the tube,

Fig.12 the clamping screw according to Fig. 10 after tightening

the union nut and the resulting radial

Compression of the clamping insert, whereby the radially inwardly projecting, not even

flexible projections are pressed into the pipe surface ^ and

Fig. 13 shows on an enlarged scale the detail marked D in Fig. 12 with the clamping insert with short

Projection which is pressed into the slightly flexible outside of the pipe after screwing.

In the different embodiments described below, parts that are essentially identical in terms of their function are provided with identical reference numbers even in modified versions.

fc A compression fitting, designated as a whole by 1, is used in the exemplary embodiment according to Fig.1, 10 and 12 to fasten a line, for example a pipe 2, to an opening 3 in a wall 4. For this purpose, it has a receiving sleeve 5 with an external thread 6, which in the exemplary embodiments is screwed into the opening 3 with a second thread 7 and sealed by means of a sealing ring 8. A counter sleeve, in the exemplary embodiment a union nut 9, can be screwed onto this receiving sleeve 5, which has an internal thread 10 matching the external thread 6.

5 It is important to use a clamp insert to hold the pipe 2, which

in the exemplary embodiment is designed as a clamping ring 11 and has slots 12 that run along its axial extent and are open at least on one end face, which can also run obliquely to a radius, as can be seen in Figures 4 and 5. This clamping ring 11 can be acted upon and gripped by means of a ring-like, tapering pressure surface 13 on one of its end faces 14," whereby the pressure surface 13 is located on the inside of the union nut 9 and the end face 14 and this pressure surface 13 in the exemplary embodiment are each designed as a cone that fits together. When tightening the thread 10, due to this conical shape of the

The clamping ring 11 is deformed towards the pipe 2 by the pressure surface 13 and the front side 14, reducing the width of the slots 12 and is pressed against it, so that the desired fixing of the pipe 2 is achieved with a sufficiently high contact pressure. In this case, a support sleeve 15 is also provided, which engages in the interior of the pipe 2 in the clamping area and can absorb the pressure caused by the clamping ring 11 if the pipe 2 is made of a flexible material.

In Fig.l, 10 and 12 it is shown that the pipe 2 is arranged vertically and is to be connected with its upper end to the wall 4 via the compression fitting 1.

fc the support sleeve 15 can be held comfortably on the upper end face of the pipe 2 because it encompasses this upper pipe opening, but the union nut 9 would slide down on the pipe 2 as long as it is not at least partially screwed to the receiving sleeve 5. To prevent this from happening, in all of the embodiments 0 explained in detail below, it is provided that the union nut 9 or the clamping insert 11 connected to it at least in the axial direction or a retaining ring 16 connected to the union nut 9 and/or the clamping insert 11 at least in the axial direction engages the outside of the pipe 2 in a frictional or self-adhesive and displaceable manner.

In the embodiment according to Fig. 1 to 5, the clamping insert 11 has projections 17 directed radially inwards that can be bent in the axial direction by the pipe 2, which can be seen clearly in Fig. 2 and 3, once in a deformed and once in an undeformed position, and also in plan view in Fig. 4 and 5. The radial dimension of the projections 17, which can be seen particularly clearly in Fig. 3, is larger than the difference between the inner diameter of the clamping insert 11 and the outer diameter of the pipe 2. If the pipe 2 is inserted into the clamping insert 11 or, conversely, the clamping insert 11 is inserted from above together with the union nut 9 over the pipe, the projections

- 17 are bent in the axial direction in the manner clearly visible in Fig.2 and, due to their elastic restoring forces, exert a frictional force on the outside of the pipe 2, by means of which the clamping insert 11 is fixed in any position so that it in turn temporarily fixes the union nut 9 which overlaps it in an axial direction. The holding forces are so low, however, that the union nut 9 can be easily moved upwards from this temporary holding position 0 shown in Fig.1 when the pipe 2 has been brought into its final position within the receiving sleeve 5 in order to then screw the threads 6 and 10 together. This prevents the union nut 9 from slipping on the downwardly facing part of the pipe 2.

^ directed pipe 2 may slide downwards over a very long distance 5 or has to be temporarily held in place by complex auxiliary measures near the installation point.

It can be seen in Fig. 4 that several radially inward-directed projections 17 are evenly distributed on the inner circumference of the passage opening 18 of the clamping insert 11, so that a largely centric pre-fixing of the union nut 9 with its clamping insert 11 is possible.

In Fig.5, a ring-shaped, approximately lip-shaped projection 17 is attached to a clamping insert which is otherwise identical

11, which is interrupted by radial-axial slots 19 in the area of the slots 12 of the clamping insert 11. The function of both the arrangement according to Fig.4 and Fig.5 is approximately the same and corresponds to the illustration in Fig.2. From Figs. 3 and 4 it is also clear that the projections 17 projecting radially into the inner cross section or the passage opening 18 of the clamping insert 11 are designed as flat tongues in the axial direction, which taper in the radial direction. Thus, approximately as much of the projections 17 bend as is required by the outer diameter of the pipe 2, which means that pipes of different

^ Nominal diameters are gripped with the same clamping insert 11 and held self-adhesively but movably on a pipe 2.

It is advantageous if the projections 17 are elastically bendable and consist of an elastically flexible plastic, whereby in the embodiment according to Fig. 1 to 5 they are connected in one piece with the clamping insert 11. Since the clamping insert 11 is also elastically deformable in that its slots

12 can be compressed against the elasticity of the material, it is advantageous to also manufacture the projections 17 in one piece and thus from the same elastic material.

In this embodiment, as can be clearly seen in Fig. 1 to 3, the projections 17 are arranged near the front side 20 of the clamping insert 11, which faces the thread 10. This ensures that when the clamping insert 11 is pushed onto the pipe 2 from above, a larger part of the clamping insert 11 initially takes up part of the pipe before the projections 17 are then deformed by the pipe front side and then the pipe surface. This initially results in a certain guidance of the pipe 2 relative to the clamping insert 11, so that the deformation of the projections 17 takes place automatically.

In the embodiment according to Figures 6 and 7,

that the union nut 9 has projections 17 directed radially inwards, which can be bent in the axial direction by the pipe 2, in the area of its smallest inner diameter at the lower end of the tapered pressure surface 13 in the position shown. The same applies to these projections 17, which are connected in one piece with the union nut, as to the projections 17 on a clamping insert 11, i.e. with regard to the arrangement and function of the projections 17 connected to the union nut 9, the same applies as to the projections 17 connected to the clamping insert 11. It is advantageous that the clamping insert 11 does not require any projections, so that any, merely

^ a clamping insert 11 suitable for the dimensions can be used.

A further embodiment is shown in Fig.8, in which, in addition to a conventional union nut 9 and a conventional clamping insert 11, a retaining ring 16 is arranged between the radially inwardly projecting thread 10 and the clamping insert 11, which in turn has one or more projections 17 resting on the outside of the pipe in order to generate the friction force described above, by means of which the union nut is held in a frictionally locked but displaceable manner in any position even on a downwardly directed or vertical pipe 2. It can be clearly seen in Fig.8 how the projections 17 rest on the outside of the pipe and the threaded area of the union nut 9 rests on the outside of the retaining ring 16. Here too, the projections 17 are designed to taper in the radial direction in order to enable favorable deformation.

0 In the embodiment according to Fig. 9, it is provided that the clamping insert 11 contains a sealing ring which, in addition to its sealing function in the position of use, acts as a retaining ring 16 and frictionally engages the surface of the pipe 2 even before the screw connection. When the union nut 9 is fitted together with its 5 clamping insert 11 and the

Sealing ring 16 is frictionally connected to the outside of the pipe, so that the union nut 9 can be temporarily held on a downward-running or vertical pipe at any height. Such a retaining ring 16 designed as a sealing ring is very inexpensive, as it is a commercially available part.

In the embodiment already mentioned at the beginning according to Fig. 10 to 13, for a preliminary frictional hold of the union nut 9 with its clamping insert 11 on the vertically arranged pipe 2, also radially inwards into the clear

projections 17 protruding from the passage of the clamping insert 11 are provided. However, these projections 17 are relatively short according to Fig. 11 and in any case shorter than those according to the embodiment according to Figs. 1 to 3. The length of these projections 17 corresponds approximately to the radial play of the clamping insert 11 or its radial elastic expandability within the union nut 9 or is even somewhat less than this play or this expandability, so that when the union nut 9 with its clamping insert 11 is put on, a frictional connection is created between the pipe 2 and the clamping insert 11, by which the union nut 9 can in turn be temporarily fixed in a pre-assembly position according to Fig. 10 near the upper end of the pipe 2. The frictional connection is created by the elastic flexibility of the clamping insert and possibly also to a small extent of the pipe 2, which is made of elastic material.

It can be seen, particularly in Figs. 12 and 13, that the projections 0 17 in this embodiment are not or at most only slightly flexible, because when the union nut 9 is tightened in the use and clamping position, they are pressed slightly into the outside of the pipe, which is made of a correspondingly flexible plastic. This further improves the clamp connection 5 in the use position, because the clamping insert

·

can also create a positive connection in the axial direction. In this case, the projections 17 have an additional function because they initially serve in the pre-assembly position to provide a temporary friction-locked holding of the union nut 9 with its clamping insert 11, but in the use position they provide an » improved axial connection with the outside of the pipe.

In this case too, the projections 17 are expediently connected in one piece to the clamping insert 11.

Overall, in all execution games, there is a

A small screw connection 1 or pipe screw connection, the screwable counter sleeve or union nut 9 on the connecting pipe 2 has a self-adhesion, which is dimensioned in such a way that it at least corresponds to the weight of the union nut 9 with its clamping insert 11 or slightly exceeds this weight, so that the union nut 9 is held at any height on the pipe 2 in a frictionally locked but movable manner.

Expectations

Claims (5)

- r claims 1. Compression fitting (1) for lines, pipes (2), heating pipes, hoses or for cables or other elongated bodies, in particular made of plastic, with a receiving sleeve (5) having a thread (6) and with a counter sleeve or union nut (9) that can be screwed onto it and with a clamping insert, clamping ring (11) or similar clamping part that can be pressed onto the pipe (2) or similar elongated body by the screw connection, which has slots (12) that run along its axial extent and are open at least on one end face (14), the clamping part (11) being acted upon or overlapped by at least one ring-like, tapering pressure surface (13) on one of its end faces and when the thread of the counter sleeve or union nut (9) is tightened with a tapering shape, for example by means of a cone or rounding, reducing the width of the slots (12) is deformable towards the pipe (2) or the elongate body and can be pressed against it and, in the case of an elongate body which is hollow on the inside, in particular a support sleeve (15) in the clamping area engages into the interior of the elongate body or pipe (2), characterized in that the counter sleeve or union nut (9) and/or the clamping insert (11) or the like connected to it at least in the axial direction and/or a holding body or retaining ring (16) connected to the counter sleeve or union nut (9) or the clamping insert (11) or the like at least in the axial direction engages the outside of the elongate body in a frictionally locking or self-adhesive and displaceable manner. 2. Compression fitting according to claim 1, characterized in that the union nut (9) or the clamping insert (11) or the like contains a sealing ring which, in addition to its 5 sealing function in the position of use, already functions as a retaining ring (16). before screwing, it frictionally engages the surface of the elongated body. 3. Clamping screw connection according to claim 1 or 2, characterized in that the union nut (9) and/or the clamping insert (11) and/or the holding body or retaining ring (16) has at least one radially inwardly directed projection (17) which frictionally acts on the elongated body (tube 2).
10 4. Small screw connection according to one of claims 1 to 3, characterized in that the projection(s) (17) on the clamping insert (11) protrudes inwards into the inner opening (18) of the clamping insert (9) approximately by its radial play relative to the elongated body and/or by the radial expandability of the clamping insert (11) within the union nut (9) of the front screw connection or less and in particular is/are not or only slightly flexible. 0 5. Small screw connection according to one of claims 1 to 3, characterized in that the projection (17) can be bent elastically, if necessary permanently, by the elongated body (tube 2) acting on it. 6. Clamping screw connection with a counter sleeve or union nut and a clamping insert for gripping elongated bodies of different nominal diameters according to one of claims 1 to 3 or 5, characterized in that the radial dimension of the bendable projection (17) or the bendable projections (17) is greater than the difference between the different nominal radii of the elongated bodies to be gripped. . Clamp screw connection according to one of claims 1 to 6, characterized 5 in that on the inner circumference of the passage opening (18) of the union nut (9) or the like and/or of the clamping insert (11) and/or of the holding body or retaining ring, a plurality of radially inwardly directed projections (17) or an annular, approximately lip-shaped projection (17), ¹ S in particular with radial-axial slots (19) in the region of the slots of the clamping insert (11), are provided. 8. Clamping screw connection according to one of claims 1 to 7, characterized in that the projection(s) (17) projecting radially into the inner cross section of the union nut, the clamping insert (11) or the retaining ring are designed as axially ^ Direction is/are formed as flat tongues which taper/taper in the radial direction in particular. 9. Clamp screw connection according to one of claims 1 to 8, characterized in that the projection(s) (17) is/are elastically bendable, in particular consist of an elastically flexible plastic and is/are preferably connected in one piece to the clamping part, clamping insert (11) or the union nut (9). 10. Clamping screw connection according to one of claims 1 to 9, characterized in that the projection(s) (17) are located near one of the ^ Front sides (20) of the clamping insert (11) arranged on this 5 is/are, particularly near the front side facing the thread. 11. Clamping screw connection according to one of claims 1 to 8 or 10, characterized in that the projection(s) (17) 0 is/are integrally connected to the clamping insert (11) or the like.