DE29500338U1 - Pressing device - Google Patents

Description

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Description ;

Novopress GmbH Presses and Pressing Tools & Co. KG Scharnhorststr. 1, D-41460 Neuss

Pressing device

The invention relates to a pressing device for radially pressing press fittings onto pipe ends with a split, but closable press ring, which has at least one radially inwardly movable pressing element, which can be moved radially inward relative to the press ring via a feed device.

To connect pipe ends, it is known to use sleeve-shaped press fittings that are plastically deformable and made of metal, preferably steel. Their inner diameter is so much larger than the outer diameter of the pipe ends to be connected that they are permanently deformed when radially pressed together to rest on the surface of the pipe ends. Such pipe connections and the associated press fittings can be found, for example, in DE-C-I 187 870 and DE-C-40 12 504.

Various forms of pressing devices have been developed for radial compression. A number of such pressing devices can be found in EP-A-0 451 806. Figures 7 and 8 of this document show a pressing device with a pressing ring that is open at a closing point and is made up of articulated members that carry arched pressing jaws. Such a pressing ring can be placed like a sleeve around the point to be pressed and then pulled together with the help of an electric motor or hydraulically operated closing device.

A further development of this pressing device is shown in DE-C-42 40 427. It has a coupling link at the closing point of the pressing ring, via which the adjacent links can be temporarily secured and the pressing ring can thus be closed. This prevents the pressing ring from slipping.

In another type of pressing device with a split but closable pressing ring, the pressing jaws are connected to the pressing ring via feed devices. With the help of these feed devices, which are usually hydraulically operated, the pressing jaws can be moved radially inwards relative to the pressing ring after it has been closed until the pressing jaws are in contact with one another at the front and thus form a closed pressing chamber. For example, reference can be made to the generic DE-A-2 118 782.

All known pressing devices have in common that curved pressing jaws are used as pressing elements, which in the pressing position combine to form a closed pressing chamber. The disadvantage of this type of pressing device is that when the pressing jaws are brought together, distortions form, as well as outward-protruding noses in the areas between the pressing jaws, which prevent complete pressing and can be the cause of leaks. Since the pipes usually carry liquids, a leak can lead to considerable damage to the building.

A further disadvantage is that the previously known pressing devices can often not be used in confined spaces because they require too much space. With the first type of pressing device, the closing device for pulling the pressing ring together at the closing point must apply high forces. This requires a heavy and difficult to handle, bulky and expensive closing device. With the second type of pressing device, the pressing ring itself is very bulky and

Therefore, it cannot be placed around the press fitting in confined spaces. The application area of the previously known pressing devices is therefore limited.

The invention is based on the object of designing a pressing device of the type mentioned at the beginning in such a way that undesirable deformations of the fitting are avoided during pressing and that it can also be used in confined spaces.

This object is achieved according to the invention in that the press ring has rotating rollers distributed over the inner circumference, at least one of which is designed as a press roller forming the press element. The press device differs fundamentally from the known press devices in that the press elements are not press jaws, but at least one press roller. This also results in a fundamental difference in handling. While the press ring in the known press devices remains essentially stationary after being placed around the press fitting, the pressing in the press device according to the invention takes place by turning the press ring and simultaneously moving the press roller(s). This rolling "pressing" avoids undesirable deformation of the press fitting, thus ensuring a uniform reduction in the diameter of the press fitting in the direction of the pipe end. This achieves a reliable seal between the press fitting and the pipe end.

A further advantage is that the suspension of the rollers and the feed device(s) required for the press roller(s) can be designed to be compact and simple. The press device according to the invention is therefore characterized by its low weight and small space requirements and can therefore also be used under difficult conditions, especially in confined spaces.

In the embodiment of the invention, it is provided that at least three rollers, preferably five to eight rollers, are provided, and

It is advisable to distribute the pressure evenly over the circumference. This provides good support for the press ring. If - as also suggested - there are several press rollers, which are preferably distributed evenly over the circumference, it is not necessary to let the press ring make a full rotation. It is then sufficient if the press ring is moved back and forth by a swivel angle that corresponds to the angular distance between the press rollers. The number of press rollers does not have to match the total number of rollers. However, it can be advisable for all rollers to be designed as adjustable press rollers.

In principle, it is possible to carry out the rotational movement of the press ring by hand, for example with the help of an attached lever or the like in the case of greater forces. To avoid this, however, it can be provided that at least one of the rollers is equipped with a drive, for example an electric motor. This does not necessarily have to be the or one of the press rollers, but is useful because their contact pressure is high. In particular, for the driven rollers, it is recommended to provide a profile on the peripheral side to prevent slippage. The profile can also contain or consist of an engraving to identify the pressing point.

The press ring can be designed as a link ring in a manner known per se, with the rollers being rotatably mounted in the links, the press roller(s) mediating the feed device. Alternatively, the rollers can also connect the links in the manner of a chain.

According to a further feature of the invention, at least the press roller(s) is/are divided into several roller discs that are positioned next to each other. These can move independently of each other, thereby avoiding friction losses due to the different diameters of the roller discs.

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if the press roller is profiled - as intended - for example, has an annular groove to accommodate the annular bead containing the seal in the press fitting.

As far as the feed device(s) for the radial adjustment of the press roller(s) are concerned, various designs are conceivable. It is possible to design the feed device(s) as a hydraulically actuated piston-cylinder unit, as is already known in the state of the art for pressing devices with pressing jaws (DE-A-2 118 782).

However, mechanical solutions are also possible. The respective feed device can have at least one rolling track, on which the associated press roller rests and which runs radially inwards against the intended direction of movement of the press ring. The respective press roller must be movable in the circumferential direction so that it can roll on the rolling track when the press ring rotates, with the result that it is pressed radially inwards. The rolling track should have a first, radially tapered section and a second, adjoining section running in the circumferential direction so that the pressing is even over the circumference.

The respective rolling track can be arranged on the press ring. Alternatively, it is provided that a lockable feed ring is assigned to the press ring, which has the rolling track(s). This design has the advantage that the press roller(s) can be guided immovably in the circumferential direction and that the feed per angular unit of rotation of the press ring can be freely selected. It goes without saying that the feed ring, like the press ring, should be designed to be divisible so that both can be placed over the pressing point from the side.

A further mechanical design of the feed device(s) can consist of a radially operating thread adjustment

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This can then be operated manually. However, a twisting device can also be provided, which automatically ensures a thread adjustment when the press ring is pivoted or rotated. This can be done, for example, in such a way that the twisting device(s) is/are each designed as a lockable gear ring extending in the circumferential direction, with the gear ring expediently extending over the circumference of the press ring, so that if there are several thread adjustments, all of them can mesh with the gear ring.

As a third alternative, in the case where several press rollers are provided, it is proposed that the feed device has at least one tensioning chain which is placed around the press rollers and can be tensioned by means of a tensioning device supported on the press ring or a press roller. In this design, several press rollers are fed by a tensioning device. The tensioning device should have a spring element to maintain the tension when the press rollers are fed. This makes it unnecessary to readjust the tensioning device when the press ring rotates and thus when the press rollers are fed.

The clamping device can be designed as a hydraulically actuated piston-cylinder unit. In this case, however, a hydraulic source is required. Alternatively, the clamping device can also have a thread adjustment, which is then expediently connected to a twisting device, which ensures that the thread adjustment is fed when the press ring is rotated. The twisting device can be designed as a lockable gear ring extending in the circumferential direction, with which the thread adjustment meshes.

The invention is illustrated in more detail using exemplary embodiments in the drawing. They show

Figure 1 a pressing device with pipe end and pressing

fitting in axial section;

Figure 2 the pressing device according to Figure 1 in the

front view;

Figure 3 another pressing device in the front

view;

Figure 4 the upper half of the pressing device according to

Figure 3 in axial section and

Figure 5 another pressing device in the front

view.

In all figures below, identical or functionally identical parts are provided with the same reference numbers.

The pressing device 1 shown in Figures 1 and 2 has a pressing ring 2 which is composed of six pressing ring segments 3, 4, 5, 6, 7, 8. The pressing ring segments 3, 4, 5, 6, 7, 8 are curved and connected to one another via joints 9, 10, 11, 12, 13, 14 which are only shown schematically here. At least one of the joints 9, 10, 11, 12, 13, 14 is visible, so that the pressing device 1 can be placed around a pipe from the side.

Each press ring segment 3, 4, 5, 6, 7, 8 has a guide cage 15, 16, 17, 18, 19, 20 that is open radially inwards and is held stationary relative to the respective associated press ring segment 3, 4, 5, 6, 7, 8. A press roller 21, 22, 23, 24, 25, 26 is guided in each of the guide cages 15, 16, 17, 18, 19, 20, in each case with the outer half. Towards the inside, the press rollers 21, 22, 23, 24, 25, 26 protrude above the guide cages 15, 16, 17, 18, 19, 20 and also above the press ring segments.

3, 4, 5, 6, 7, 8. The press rollers 21, 22, 23, 24, 25, 26 have laterally projecting press roller axes 27, 28, 29, 30, 31, which rest on rolling tracks 33, 34, 35, 36, 37, 38, which belong to the guide cages 15, 16, 17, 18, 19, 20. The rolling tracks 33, 34, 35, 36, 37, 38 run obliquely to the circumferential direction defined by the press ring 2, thus have a radial component.

As shown in particular in Figure 1, the press rollers 21, 22, 23, 24, 25, 26 are each made up of three parts. There is a center disk 39, 40, which has an annular groove 41, 42. The center disks 39, 40 are flanked by two complementary side disks 43, 44, 45, 46, which have a larger diameter than the center disks 39, 40 and their outer sides rest against the inner sides of the guide cages 15, 16, 17, 18, 19, 20 for guidance. The center disks 39, 40 can move relative to the side disks 43, 44, 45, 46 and are connected in a rotationally fixed manner to the press roller axes 27, 28, 29, 30, 31, 32.

In the illustration according to Figure 1, the press ring 2 is placed over a pipe connection point. The pipe connection point consists of a cylindrical pipe end 47 and a press fitting 48 partially placed over it. The press fitting 48 has ring-shaped fitting beads 49, 50 protruding outwards on both ends, into which sealing rings 51, 52 are inserted on the inside. In the middle area, the press fitting 48 has a constriction 53, which serves as a stop for the pipe ends 47 to be inserted from both sides.

The pressing device 1 is placed around the left-hand fitting bead 49 of the press fitting 48 in such a way that the ring grooves 41, 42 of the pressing rollers 21, 22, 23, 24, 25, 26 rest against the fitting bead 49 from the outside, and after closing the pressing ring 2 initially without any major pre-tension. In this case, the pressing rollers 21, 22, 23, 24, 25 are located in a deviation from the illustration in Figure 2.

next offset in the circumferential direction against the direction of rotation indicated by arrow A, so that the press roller axes 27, 28, 29, 30, 31, 32 rest on the radially distant part of the rolling tracks 33, 34, 35, 36, 27, 38. For the pressing process, the press ring 2 is rotated in the direction of arrow A. This can be done manually or by an electric motor drive of one of the press rollers 21, 22, 23, 24, 25, 26. The rotation of the press ring 2 results in the press rollers 21, 22, 23, 24, 25, 26 rolling on the fitting bead 49 and thus the press roller axes 27, 28, 29, 30, 31, 32 rolling on the rolling tracks 33, 34, 35, 36, 37, 38 with the further consequence that the press rollers 21, 22, 23, 24, 25, 26 move in the circumferential direction relative to the press ring 2 and are pressed radially inwards due to the inclination of the rolling tracks 33, 34, 35, 36, 37, 38. This leads to the fitting bead 49 and the adjacent area of the press fitting 48 being plastically deformed inwards, to the point where the pipe end 47 is also constricted. In this way, the sealing ring 51 is pressed onto the pipe end 47 with the radial force required for a good seal. This creates the connection between the pipe end 47 and the press fitting 48. After inserting the pipe end (not shown here) to be connected to the pipe end 47 from the open side of the press fitting 48, the same process is repeated using the pressing device 1.

The pressing device 61 shown in Figures 3 and 4 has a similar basic structure to the pressing device 1 with a pressing ring 2 composed of six pressing ring segments 3, 4, 5, 6, 7, 8. It is also visible on one of the joints 9, 10, 11, 12, 13.

A guide cage 15, 16, 17, 18, 19, 20 is provided in each of the press ring segments 3, 4, 5, 6, 7, 8. However, these are not held in place, but are guided radially in the press ring segments 3, 4, 5, 6, 7, 8. A press roller 21, 22,

23, 24, 25, 26 are rotatably mounted and therefore cannot move relative to the associated guide cage 15, 16, 17, 18, 19, 20 apart from the rotary movement.

The press ring 2 is surrounded by a feed ring 62, which is connected to the press ring 2 in such a way that it cannot move in the circumferential direction. The feed ring 62 has radially directed threaded holes opposite the press rollers 21, 22, 23, 24, 25, 26, into which feed screws 63, 64, 65, 66, 67, 68 are screwed in such a way that they rest against the outsides of the guide cages 15, 16, 17, 18, 19, 20. The outside ends of the feed screws 63, 64, 65, 66, 67, 68 have gears 69, 70, 71, 72, 73, 74, which mesh with a gear ring 75. The gear ring 75 is seated on an annular disk 76, which is connected to a pipe sleeve 77, which sits on the pipe end 47 and is connected to it in a rotationally fixed manner. In this way, the gear ring 75 is also held in a rotationally fixed manner.

As can be seen from Figure 4 - the lower half is identical to the upper half shown - in comparison to Figure 1, the pressing device 61 is in the same position as the pressing device 1 and surrounds the left-hand fitting bead 49 of the press fitting 48. For pre-pressing, the press ring 2 is rotated together with the feed ring 62. This results in the gear wheels 69, 70, 71, 72, 73, 74 meshing with the gear ring 75 and rotating the feed screws 63, 64, 65, 66, 67, 68. This in turn leads to a radially inward movement of the feed screws 63, 64, 65, 66, 67, 68, which is transferred to the guide cages 15, 16, 17, 18, 29, 20 and thus leads to a feed of the press rollers 21, 22, 23, 24, 25, 26. In this way, the fitting bead 49 is slowly deformed against the pipe end 47 until a tight connection is made between the pipe end 47 and the press fitting 48. After turning back the press ring 2, the pressing device 61 can be removed again and used to connect the press fitting 48 to the other pipe end (not shown here).

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If a ratchet is provided between the connection of the feed screws 63, 64, 65, 66, 67, 68 and the corresponding gears 69, 70, 71, 72, 73, 74, the compression of the press fitting 48 can also be carried out by swinging the press ring 2 back and forth. In this case, the feed of the press rollers 21, 22, 23, 24, 25, 26 only takes place in one direction. This results in the press fitting 48 being pressed evenly over the entire circumference.

The pressing device 81 shown in Figure 5 also uses a pressing ring 2 that is identical to the pressing ring 2 according to Figure 3. The guide cages 15, 16, 17, 18, 19 are thus only guided radially in the pressing ring segments 3, 4, 5, 6, 7, 8. Accordingly, the pressing rollers 21, 22, 23, 24, 25, 26 are only rotatably mounted in the guide cages 15, 16, 17, 18, 19, 20.

The press rollers 21, 22, 23, 24, 25 have axially outwardly projecting deflection disks 82, 83, 84, 85, 86. A feed chain 88 is placed around the outside of the deflection disks 82, 83, 84, 85, 86. The ends of the feed chain 88 are attached to a block 89 shown schematically. This has a radially aligned threaded hole into which a tension screw 90 is screwed. It is supported by a tension spring 91 on the outside of the guide cage 20, which is located at the bottom in the illustration. It is understood that the illustration is only schematic.

For a pressing process, the pressing device 81 is placed over a fitting bead 49 of a press fitting 48 in the same way as the pressing devices 1 and 61 and the pressing ring 2 is closed. The feed chain 88 is then placed over the deflection discs 82, 83, 84, 85, 86, as shown in Figure 5. A force can then be applied to the feed chain 88 and thus to the press rollers 21, 22, 23, 24, 25 and as a reaction force to the press roller 26 via the tensioning screw 90.

that the pressing rollers 21, 22, 23, 24, 25, 26 are pressed radially inwards and thereby compress the fitting bead 49 in the manner already described. By turning the pressing device 61 together with block 89, clamping screw 90 and tension spring 91, the compression is evenly distributed over the circumference.

For the clamping screw 90, in a similar way to the pressing device 61 according to Figures 3 and 4, a gear ring can be provided that is firmly connected to the pipe end 47, which then meshes with a gear that is placed on the screw head of the clamping screw 90. In this way, when the pressing ring 2 is rotated, the feed chain 88 is automatically successively tensioned. A tension spring 91 can be dispensed with, i.e. in this case the clamping screw 90 lies directly on the guide cage 20. There is also the possibility, already described above, of attaching a ratchet between the gear and the clamping screw 90, so that the pressing takes place by swinging the pressing ring 2 back and forth, whereby the clamping screw 90 is only fed in one direction of rotation.

Claims (25)

Claims Novopress GmbH Presses and Pressing Tools & Co. KG. Scharnhorststr. 1, D-41460 Neuss Pressing device 1. Pressing device for radially pressing press fittings onto pipe ends, with a split but closable press ring, which has at least one radially inwardly movable press element, which can be moved radially inward relative to the press ring via a feed device, characterized in that the press ring (2) has rotatable rollers (21, 22, 23, 24, 25, 26) distributed over the inner circumference, of which at least one is designed as a press roller (21, 22, 23, 24, 25, 26) forming the press element. 2. Pressing device according to claim 1, characterized in that at least three rollers (21, 22, 23, 24, 25, 26) are present. 3. Pressing device according to claim 1 or 2, characterized in that several press rollers (21, 22, 23, 24, 25, 26) are present, which are evenly distributed over the circumference. 4. Pressing device according to claim 3, characterized in that all rollers are designed as press rollers (21, 22, 23, 24, 25, 26). 5. Pressing device according to one of claims 1 to 4, characterized in that at least one roller is provided with a drive. 6. Pressing device according to claim 5, characterized in that the roller(s) provided with the drive is(are) a press roller. 7. Pressing device according to one of claims 1 to 6, characterized in that at least one of the rollers (21, 22, 23, 24, 25, 26) is provided with a profile on the peripheral side. 8. Pressing device according to one of claims 1 to 7, characterized in that the pressing ring (2) is designed as a link ring and the rollers (21, 22, 23, 24, 25, 26) are rotatably mounted in the links (3, 4, 5, 6, 7, 8). 9. Pressing device according to one of claims 1 to 8, characterized in that the pressing ring is designed as a link ring and the rollers connect the links in the manner of a chain. 10. Pressing device according to one of claims 1 to 9, characterized in that at least the press roller(s) is/are divided into several roller disks (39, 40, 43, 44, 45, 46) sitting next to one another. 11. Pressing device according to one of claims 1 to 10, characterized in that the feed device(s) is/are each designed as a hydraulically actuated piston-cylinder unit. 12. Pressing device according to one of claims 1 to 10, characterized in that the feed device(s) each have at least one rolling track (33, 34, 35, 36, 37, 38) on which the associated press roller (21, 22, 23, 24, 25, 26) is supported and which runs radially inwards against the intended direction of movement of the press ring (2). 13. Pressing device according to claim 12, characterized in that the rolling track(s) (33, 34, 35, 36, 37, 38) each have a first, radially tapered section and a second, adjoining and circumferentially extending section. 14. Pressing device according to claim 12 or 13, characterized in that the rolling track(s) (33, 34, 35, 36, 37, 38) is/are arranged on the press ring (2). 15. Pressing device according to claim 12 or 13, characterized in that the pressing ring is assigned a lockable feed ring which has the rolling track(s). 16. Pressing device according to one of claims 1 to 10, characterized in that the feed device has a radially operating thread adjustment (63, 63, 65, 66, 67, 68, 69). 17. Pressing device according to claim 16, characterized in that the thread adjustment (63, 64, 65, 66, 67, 68) is connected to a rotating device (69, 70, 71, 72, 73, 74, 75). 18. Pressing device according to claim 17, characterized in that the rotating device(s) has a lockable ring gear (75) extending in the circumferential direction. 19. Pressing device according to claim 18, characterized in that the toothed ring (75) extends over the circumference of the press ring (2). 20. Pressing device according to one of claims 1 to 10, characterized in that several press rollers (21, 22, 23, 24, 25, 26) are provided and the feed device(s) each have at least one tensioning chain (88) which is placed around the press rollers (21, 22, 23, 24, 25) and can be tensioned by means of a tensioning device (89, 90, 91) supported on the press ring (2) or a press roller (26). 21. Pressing device according to claim 20, characterized in that the tensioning device (89, 90, 91) has a spring member (91) for maintaining the tension when feeding the press rollers (21, 22, 23, 24, 25, 26). 22. Pressing device according to claim 20 or 21, characterized in that the clamping device is designed as a hydraulically actuated piston-cylinder unit. 23. Pressing device according to claim 20 or 21, characterized in that the clamping device has a thread adjustment (90). 24. Pressing device according to claim 23, characterized in that the thread adjustment is connected to a rotating device. 25. Pressing device according to claim 24, characterized in that the rotating device is designed as a lockable ring gear extending in the circumferential direction.