EP2749378B1 - Tool for axially pressing fittings - Google Patents

Description

The invention relates to a tool for axially pressing fittings which are radially deformed by axially pressing on a press ring in such a way that they bring about a positive and positive connection with the pipe to be connected. Fittings in which a sleeve is radially deformed by the axial pressing of a press ring are used to make connections between pipes that ensure a tight and permanent connection even at high pressures without additional sealing elements. These fittings are made in different sizes and z. B. used in high pressure fire extinguishing systems.

For pressing such fittings, the manufacturers offer special tools that are precisely tailored to their products.

Generally known are tools which, in contrast to the object according to the invention, are intended for the radial pressing of fittings, as are widely used for low-pressure systems such as heating pipes. These tools use inserts to be able to press different dimensions. Such a tool is in the EP 0826441 B1 described. This press tool is used to create a cold connection between a fitting and a pipe, the press jaws of which consist of two press jaw halves which form a press jaw. The press jaw halves are rotatably mounted on bridge parts extending transversely to the longitudinal axis of the press jaw, and a half-ring-shaped insert is interchangeably fixed in the press jaw halves in the press jaw halves. A tool suitable for axial pressing is e.g. B. in the patent US 6,199,254 B1 described. The tool disclosed there consists of two hinged housing halves and is equipped with hydraulic pistons which are arranged in a circle around the fitting. Other solutions, such as those in the US 5,694,670 are disclosed, describe pressing tools which do not act coaxially to the fitting, but grip and press the fitting with claws which are attached to a piston arranged axially parallel to the pipe.

With these pressing tool forms, high forces are transmitted to the fitting, the force application being eccentric, which leads to a high load on the tool housing due to the resulting torque. Tools with such U-shaped press jaws can only be used for small fitting sizes due to the high moments that arise and must be manually held in the correct position by the operator during the pressing process. The circular arrangement of the pistons, as already mentioned in the above US6,199,254 B1 has the disadvantage that the tool must be very large and can only be used for a specific fitting diameter, since the respective pistons act directly on the press ring to be pressed on the fitting. The US 7984538 B2 shows a press tool with a fixed and an axially movable press jaw. Here the fitting is encircled in a U-shape and fixed with inserted blocks. The force is applied by two pistons arranged on the side, which are mounted in the same housing and act together on the movable press jaw. With this construction, an extremely rigid construction is required so that the moments occurring in practice do not lead to tilting and thus jamming of the moving parts. The tool can also be used for one fitting dimension only. Due to the open design, there is also a considerable risk of trapping foreign bodies or parts of the body during operation.

Other state-of-the-art tools on the market also have a large number of pistons arranged in a circle, which, by means of power transmission to a two-part pull ring in which various inserts can be used, exert force on the fittings to be pressed. Such constructions also consist of two tool halves that are articulated together. Due to the large number of individual parts, these tools are relatively heavy and unwieldy. With these tools, too, the eccentric forces cause large moments that lead to high tool wear. As a result, the number of possible compressible dimensions is limited, so that different tool sizes are necessary in order to be able to process the fitting sizes used in the application described.

From the EP 1862715 A1 Another pressing device for the axial displacement of two parts arranged coaxially to one another is known under high pressing pressure. It is obviously part of a device that can absorb external forces, but cannot be operated manually by operating personnel during operation. In one, along a joint Hinged housing insert halves can be used, their arrangement for a high moment load of the joint due to the center distance or. Lever leads. The slide-in units are completely movable and the sliding press plates exert a high force on the oblique engagement edges, which can impair the function.
A press device of this type, similar to this, with a joint is shown in DE 102004016305 A1 out. It is only suitable for a fixed tool size and the pressure can only be adjusted to a limited extent.

The invention is therefore based on the object of developing a tool for the axial pressing of fittings which introduces the forces into the fitting to be pressed in such a way that no moments arise which strain the system. At the same time, the tool should be very compact, very light and so variable that with one tool fittings in one large dimension range, preferably between 12mm and 60mm can be pressed.

The object is achieved with the features of patent claim 1. Advantageous configurations are disclosed in the dependent claims.

A pressing tool is proposed which is suitable for pressing cylindrical fittings consisting of a sleeve and a pressing ring.

For this purpose, by axially displacing the press ring over the sleeve, by appropriately contouring the two parts, the sleeves are radially deformed inward, and the inner contour of the sleeve is thus pressed onto a tube previously inserted into the sleeve. This creates a positive and positive connection with the pipe and creates a permanent connection.

The force generated by hydraulic pistons is transferred to press plates in such a way that they act in a line almost through the centroids of the largest inserts coaxial to the fitting, so that no torque can occur that acts on the housing halves. This is possible because the pistons are not arranged in a circle around the fitting, but symmetrically to a line that runs parallel to the tool separation and approximately through the center of gravity of the inserts. As a result of this arrangement, the tool can be constructed very narrowly, so that the requirement for a construction size that is as compact as possible can be met.

Since both the pistons and the inserts that absorb the force at the other end of the fittings are stored in the same housing, the tool can be very compact. The joint connecting the two tool halves is expediently designed either over the entire height of the tool or at least at the lower and upper end of the tool, so that the two areas of the tool which are subjected to force are connected to one another and thus an exact reception of the fitting is ensured. The two inner sides of the tool halves have a cylindrical recess, which enables a preassembled assembly consisting of a fitting with an inserted pipe to be received and radially enclosed. To do this, the tool is opened, guided over the pipe fitting assembly and then closed again. The tool is locked automatically and can only be opened again after actuation of a trigger mechanism. This ensures that there is no risk of the operator being pinched or injured when the fitting is pressed. In order to be able to observe the course of the pressing that takes place within the enclosed space, a display is preferably integrated, with which the path of the pressing plate is made visible on the outside. Handles are integrated into the tool, which are arranged in such a way that the tool can be held symmetrically to the center of gravity of the tool in the open state. The trigger mechanism is arranged so that it can be operated by the holding hand with the fingertips. An adapted fitting dimension is required for each pipe dimension, which has a corresponding diameter and a specific length depending on the diameter of the pipe to be connected. With the tool according to the invention it is possible to close a large number of different fitting dimensions compress. The tool can be equipped with interchangeable inserts that are matched to the size of the fittings. These inserts are designed so that they all have the same outer contour that matches the receiving contour of the press plate and an inner contour that is matched to the respective fitting diameter. The thickness of the inserts is adjusted so that the individual length of the fitting correlates with the stroke of the tool.

Fig. 1:

eine Ansicht des geschlossenen Werkzeugs

Fig. 2:

eine Ansicht des geöffneten Werkzeugs

Fig. 3:

eine Ansicht auf eine Werkzeughälfte von Innen, mit der Anordnung der Einsätze, sowie dem Wirkmechanismus Pressplatte - Einsatz - Fitting unverpresst

Fig. 4:

eine Ansicht des Verriegelungsmechanismus (geöffnet)

Fig. 5:

eine Ansicht Verriegelungsmechanismus geschlossen

Fig. 6:

eine Ansicht der Griffe, des Entriegelungsmechanismus und der Stellungsanzeige

Fig. 7:

eine Ansicht Wirkmechanismus Pressplatte -Einsätze-Fitting verpresst

Fig. 8:

eine Zylinderanordnung

Fig. 9:

einen Längsschnitt

Fig. 10:

eine Ansicht, die die Montage der Stopfen von unten zeigt

Fig. 11:

eine Ansicht eines oberen Einsatzes

Fig. 12:

eine Ansicht mit einer alternativen Ausführungsform bei der die Kolbenmontage in einer Unterbaugruppe von der Seite her erfolgt

Fig. 13:

eine Ansicht mit einer alternativen Ausführungsform bei der die Kolbenmontage in einer Unterbaugruppe von der Seite erfolgt als Explosionsansicht,

Fig. 14:

eine weitere Ausführungsform der Verriegelung im erfindungsgemässen Werkzeug

Fig. 15:

eine weitere Ausführungsform der erfindungsgemässen Einsätze

Fig. 16:

eine weitere Ausführungsform der erfindungsgemässen Gehäuseteile.

The invention is described in more detail in an exemplary embodiment with reference to a drawing. In the drawing they show

Fig. 1:

a view of the closed tool

Fig. 2:

a view of the open tool

Fig. 3:

a view of a tool half from the inside, with the arrangement of the inserts, as well as the mechanism of action press plate - insert - fitting unpressed

Fig. 4:

a view of the locking mechanism (opened)

Fig. 5:

a view locking mechanism closed

Fig. 6:

a view of the handles, the release mechanism and the position indicator

Fig. 7:

a view mechanism of action press plate -inserts-fitting pressed

Fig. 8:

a cylinder arrangement

Fig. 9:

a longitudinal section

Fig. 10:

a view showing the assembly of the plugs from below

Fig. 11:

a view of an upper insert

Fig. 12:

a view with an alternative embodiment in which the piston assembly in a subassembly takes place from the side

Fig. 13:

2 shows a view with an alternative embodiment in which the piston is assembled in a subassembly from the side as an exploded view,

Fig. 14:

a further embodiment of the locking in the tool according to the invention

Fig. 15:

a further embodiment of the inserts according to the invention

Fig. 16:

a further embodiment of the housing parts according to the invention.

In Fig. 1 the tool is shown in the closed state viewed from above. It consists of the housing parts 1 and 2 and the two handles 3 and 4. On the front side between the handles, a plug coupling 5 is attached for connection to a hydraulic pump by means of a hose with a plug coupling. The two upper inserts 6 and 7 are also visible.

In the Fig. 2 the tool is visible in the opened (open) state. In this position, the tool can be guided over the assembly 19 and then closed again. How from Fig. 3 can be seen, the assembly 19 consisting of the tube 20, the fitting 21 to be pressed and the press ring 22 is completely enclosed by the tool. It is shown that the press ring 22 rests on the insert 13 in the starting position and the fitting body 21 rests almost on the insert 6. The insert 13 is received by the press plate 14. In this position, the press plate 14 is pressed against the housing part 1 by the return springs 23. The insert 6 is form-fitting from the housing 1 recorded and absorbs the force that occurs during pressing. This is transmitted through the insert 13, which is located in the press plate 14, to the press ring 22 and is diverted to the fitting body 21. The force is generated by pistons 16 which are pressurized with hydraulic pressure by an external pump (see Fig. 7 ) and transferred to the pressure plate 14.

In Fig. 7 the pressed fitting is shown in the tool. The press ring 22 is completely pushed onto the fitting body 21 and has connected the inner tube 20 to the fitting. The press plate 14 has reached the uppermost position and the return springs 23 are under maximum tension. After the hydraulic pressure has been reduced, the return springs bring the pressing plate 14 back into the starting position.

In Fig. 5 a closed locking mechanism is shown. This consists of a pin 12, which is biased by a spring 11 so that it engages in a tab 10. The pin 12 can be pulled by the button 9 and the tool is unlocked and can then be opened by rotating the housing part 1 about the axis 17. The pin 12 is completely axially displaceably mounted in the housing part 2. The tab 10 is fixed in the housing 1. In Figure 4 the tool is shown in the opened state. The housing 1 is rotated about the axis 17 by the closing movement. During this movement, the pin 12 is moved through the tab 10 and tensioned against the spring 11. In the closed position, the pin 12 can move into the tab 10 by the spring force and thus automatically lock the tool. In use, the tool is held by the fitter on the two integrated handles 3 and 4. In Figure 6 it is shown that the handles are connected to the housing parts 1 and 2 by means of tabs 24 and 25. A pull button 9 is arranged so that it can be operated with the fingertips from the holding position.

In Figure 8 the arrangement of the pistons 16 can be seen. These are arranged so that the resulting force is almost on the center of gravity of the inserts 6 and 13. The forces can thus be dissipated into the housing without creating a moment. The swivel joint in housing part 1 is formed by axis 17 and is arranged outside the center. The two housing parts 1 and 2 can thus be performed in mirror image. The housing part 2 also has an axis 18. The housing part 2 can be pivoted about this. This joint is advantageously blocked so that simple operation is possible. The two housing parts 1 and 2 are connected to one another by two tabs 27 and 29 and via the hydraulic distributor 26. This is in Fig. 6 seen. The upper tab 27 also serves as a guide for the pin 12 of the lock and as a counter bearing for the compression spring 11, which presses the locking pin into the locked position. In the hydraulic distributor 26, the hydraulic medium is introduced through the plug-in coupling 5 and then passed on through bores in such a way that it is passed axially to the cylinders via corresponding bores in the housing parts 1 and 2. The hydraulic distributor 26 functions as a joint. The two axes 17 and 18 are mounted so that both joints are formed over the entire height of the tool. The axes are held by the tabs 24 and 25 in the housing parts 1 and 2. Since the pressing process in the completely enclosed interior of the Tool runs, the progress of the pressing can be tracked by means of indicator pins 8, for example on the sides of the tool. The inserts 13 can be connected to the press plates by means of the screws 28.
In Fig. 11 an insert 6 is shown. In this, the force-absorbing surface 31 is formed such that the size of a recess 30 z. B. as a chamfer, the position of the force application point is controlled.

In Figure 10 a possible embodiment of the assembly of the piston 16 in the housing parts 1 and 2 is shown. In this embodiment, the pistons are inserted into the housing from below and the housing bore is closed by means of plugs 15. The plugs simultaneously form the guide for the pistons 16. The advantage of this embodiment is that the guide sleeve integrated in the plug 15 can be made of a hard material, preferably steel, and the housing parts 1, 2 can be made of a lighter material, preferably aluminum , This allows the total weight of the tool to be significantly reduced compared to previous designs. An alternative embodiment is shown in FIGS Figures 12 and 13 shown. Here, the guides for the pistons are combined in a component 33, which is preferably made of steel. The pistons 34 are preassembled in this component. This assembly 35 can be inserted into a housing part 32, preferably made of aluminum, which can absorb the forces which arise during the pressing of the fittings.

In Fig. 14 a further embodiment for the locking is shown. Here, the force-absorbing components, a movable hook 38 and a fixed hook 37, are arranged in the front area of the tool. The hook 37 is connected by the shaft 39 to the release lever 36. The shaft 39 is rotatably supported. The trigger lever 36 is biased by a spring, not shown, so that the movable hook 38 automatically engages in the fixed hook 37 when the tool is closed. The device is unlocked by pressing the trigger lever 36.

In Fig. 15 An embodiment for an insert 6 is shown, in which the force-absorbing surfaces 31 are formed by cutouts 40 such that the resulting force is introduced through the center of gravity.

In Fig. 16 An embodiment of the housing parts 1 and 2 is shown, in which channels 41 for distributing the hydraulic oil are drilled in such a way that no drilling has to be made from the outside into the housing. The advantage is that no plugs 42 are required to close the bores, which can represent a potential danger for the operator if such plugs 42 would come loose when the tool was in use.

List of reference numbers

1

housing part

2

housing part

3

Handle

4

Handle

5

plug-in coupling

6

commitment

7

commitment

8th

indicator pin

9

pull knob

10

flap

11

compression spring

12

pen

13

commitment

14

press plate

15

Plug

16

piston

17

axis

18

axis

19

Fitting - press ring - tube assembly

20

pipe

21

fitting Body

22

press ring

23

Return spring

24

flap

25

flap

26

hydraulic distributor

27

screw

28

screw

29

flap

30

chamfer

31

area

32

casing

33

component

34

piston

35

Assembly of component and piston

36

sear

37

hook

38

hook

39

wave

40

cutout

41

channel

42

Plug

Claims (11)

1. Tool for the axial pressing of fittings which consist of a predominantly cylindrical sleeve and an also cylindrical compression ring which through the two-part pressing tool, the housing parts of which are connected to each other, is pushed over the sleeve, wherein radial deformation of the sleeve is brought about, wherein the tool comprises two housing parts (1, 2) connected to each other in an articulated manner and a plug coupling (5) for connection to a hydraulic pump by way of a flexible tube with a plug coupling,
   pistons (16, 34) located in the housing are arranged symmetrically in relation to a line than runs parallel to the tool partition and through the centroid of the area of the inserts so that the resulting force acts through the centroid of the area of the force-transmitting areas and that it comprises two mirror-inverted housing parts (1, 2) which are connected to each other in a rotatable manner by two joints extending over the entire height,
   characterised in that the two mirror-inverted housing parts (1, 2) can be automatically locked when they are closed.
2. Tool according to claim 1 characterised that for automatic locking a locking mechanism is used with a pin (12) that is pre-tensioned by a spring (11) in such a way that it engaged in a bracket (10).
3. Tool according to claim 2 characterised in that the locking element comprises a button (9) with which the tool can be manually unlocked.
4. Tool according to claim 1 characterised in that for automatic locking a locking mechanism is fitted with a fixed hook (37), a movable hook (38), a shaft (39) and an actuator lever (36).
5. Tool according to claim 1 characterised in that the two mirror-inverted housing parts (1, 2) are connected to each other in a rotating manner by way of two joints extending over the entire height wherein of the joints is stiffened in term of its design.
6. Tool according to any one of claims 1 to 5 characterised in the pressing procedure takes place within a space completely encompassed by the housing part (1, 2).
7. Tool according to any one of claims 1 to 6 characterised in that in the housing part (1, 2) interchangeable inserts (6, 13) are provided which take up the forces independently of each other.
8. Tool according to any one of claims 1 o 7 characterised in that each housing part (1, 2) is in one piece.
9. Tool according to any one of claims 1 to 8 characterised in that the forces in the one-piece housing part (1, 2) are taken up by way of interchangeable steel inserts, wherein the housing parts (1, 2) themselves are made of lightweight metal and in that the pistons (16, 34) are guided and borne in screwed-in steel sleeves.
10. Tool according to any one of claims 1 to 9 characterised in that the forces are taken up in a one-piece housing part (1, 2) by way of interchangeable steel inserts, wherein the pistons (16, 34) are guided and borne in a laterally inserted component (33) and in that the housing parts (1, 2) themselves are made of a lightweight metal.
11. Tool according to any one of claims 1 to 10 characterised in that to generate force, oil is supplied by an external hydraulic pump via channels (42) to the pumps (16), which are arranged in such a way that they do not pass through the outer wall of the housing parts (1, 2) at any point and therefore do not have to be sealed.

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