DE20008129U1 - Connection part for fluid lines - Google Patents

Description

G 19166 - 29.03.2000

FESTO AG & Co. 73734 Esslinqen Connection part for fluid lines

The invention relates to a connecting part for fluid lines, with a hollow screw onto which a pivoting part having at least one fluid line connection is rotatably mounted and which has a fastening section provided with an external thread at the front end for screwing in a screwing direction into a component to be equipped with the connecting part, wherein first stop means are provided on the hollow screw for preventing an axial movement of the pivoting part relative to the hollow screw that is opposite to the screwing direction, and wherein a ring flanking the pivoting part on the side facing the fastening section is coaxially mounted on the hollow screw, which ring, when the fastening section is screwed into a component, is subjected to an axial load oriented opposite to the screwing direction by this component.

Connecting parts of this type are also called screw connections and are usually used when fluid lines are to be connected to fluid technology components such as cylinders or valves, whereby a specific outlet direction of the fluid lines must be taken into account.

A connecting part known from US 5,269,346 has a hollow screw which can be screwed into the fluid power component to which the connecting part is to be fitted with a fastening section provided at the front end. A pivoting part which is provided with a fluid duct connection which allows a further fluid line to be connected is mounted on the hollow screw. By turning the pivoting part, the fluid duct connection can be brought into a desired pivoting position, whereby internal fluid channel means ensure a fluid connection between the fluid duct connection and the component fitted with the connecting part regardless of the current pivoting position. A disadvantage of the known connecting part is that the pivoting part is no longer rotatable as soon as the hollow screw is firmly screwed onto the associated fluid power component. The component then presses on a ring formed by a seal, which in turn presses the pivoting part against the first stop means of the hollow screw formed by a ring step. This means that the pivoting part is firmly clamped. In order to change the orientation of the fluid line connection, it is therefore necessary to temporarily loosen the hollow screw so that corresponding swivel positioning can only be carried out in conjunction with an operational shutdown of the associated fluid power component.

A similar problem exists with the connecting parts known from the German utility models G 8804229.4 and G 7230533.0.

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It is the object of the present invention to provide a connecting part of the type mentioned at the outset which, while maintaining compact length dimensions, allows the pivoting part to be rotated even when screwed together.

To solve this problem, the ring is designed as a stop ring which is supported on the outer circumference of the hollow screw in such a way that it is axially immovable relative to the screwing direction.

In this way, the reaction forces exerted on the stop ring by the component to be fitted with the connection part during installation of the connection part are introduced into the hollow screw and are held back by the swivel part. This prevents the swivel part from becoming firmly clamped between the stop ring and the first stop means and ensures the swivel part's rotational mobility even when the hollow screw is firmly screwed to the associated fluid power component. Since the stop ring is supported on the outer circumference of the hollow screw, the fastening section remains accessible in the usual form, which enables compact length dimensions of the connection part in the longitudinal direction of the hollow screw.

The German utility model 9106391.4 already contains a connection part designed as a pressure regulator, which has a housing that can be screwed into a component and on the outer circumference of which a rotating

Swivel part is mounted. •This is, however , : ::·· " . ^: : :: : : :.". : .·''..· * _: : ·

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It is necessary to carry out the fastening section on a separate component, which results in higher manufacturing costs and a longer installation length.

Advantageous further developments of the invention emerge from the subclaims.

In order to obtain the desired axial support of the stop ring, it could be firmly connected to the hollow screw, for example by gluing or welding.

In an alternative design, the stop ring is supported by second stop means that are positioned in front of it in the opposite direction to the screwing direction and are provided at an axial distance from the front side of the fastening section on the hollow screw. These second stop means can, for example, be formed by at least one radial projection, with an annular radial projection being recommended for optimum force absorption.

The second attachment means can be designed as an integral part of the hollow screw, which allows them to be implemented directly during the manufacture of the hollow screw. Alternatively, a separate design with respect to the hollow screw would also be possible, for example in the form of a locking ring or locking pin fixed to the hollow screw.

In all cases, it is advantageous if the stop ring is held captive on the hollow screw by measures that hold it to the hollow screw even when the hollow screw is not screwed into a component. This can prevent the stop ring from being lost during transport of the connecting part. One possible measure to prevent loss is to fix the stop ring in a press fit on the hollow screw.

In order to prevent fluid leakage in the transition area between the swivel part and the hollow screw, suitable sealing measures are provided between these two components. In this context, an annular sealing surface that works together with the swivel part to form a seal can be arranged directly on the stop ring, coaxially to it.

Furthermore, to ensure a fluid-tight connection between the connecting part and the associated fluid technology component, suitable sealing measures are provided, which expediently have a component sealing surface arranged on the connecting part and concentrically enclosing the fastening section. This component sealing surface can also be provided directly on the stop ring, which thus simultaneously represents a sealing surface carrier. The sealing surfaces can be molded directly from suitable sealing material or be part of separate sealing rings that are fixed to the stop ring.

In an alternative design, the component sealing surface is arranged on a separate sealing ring, which is

ring is coaxially positioned on the side facing the fastening section and which, when the connecting part is screwed on, is clamped between the component to be sealed and the stop ring.

The external thread of the fastening section is preferably a cylindrical and/or metric thread.

To ensure that the hollow screw can be tightened easily, it has a tool engagement section that allows the attachment of a suitable screwing tool, which is located on the side of the swivel part opposite the fastening section. This ensures optimal accessibility.

The connection part can be designed as a pure fluid guide part that has no special functional components. This could be an L-screw connection, for example. However, suitable functional means for influencing the fluid flow can also be integrated into the internal channel, so that one could speak of a functional screw connection overall. Suitable functional means can be, for example, throttling means or check means, either separately or combined.

The invention is explained in more detail below with reference to the accompanying drawings, in which:

Fig. 1 shows a longitudinal section of a preferred embodiment of the connection part according to the invention in the form of a functional screw connection in the state screwed into a fluid technology component, with a connectable fluid line being indicated by dash-dotted lines,

Fig. 2 the connecting part from Fig. 1 in plan view with view direction according to arrow II,

Fig. 3 shows a variant of the connector according to the invention in a simplified design, without integrated functional means, and

Fig. 4-6 different design and support variants of the stop ring, whereby only the fastening section of the hollow screw is shown and the other components of the connecting part are not shown.

Starting with Fig. 1 and 2, a connecting part is shown, generally designated with reference number 1, which is screwed into a threaded hole 2 of a fluid power component 3. The latter is, for example, a working cylinder, a valve or a pressure accumulator. By means of the connecting part 1, a fluidic connection can be established between the fluid power component 3 and a fluid line 4 indicated by a dot-dash line, whereby the latter can be formed by a pressure medium hose.

The connecting part 1 is suitable for use in connection with both gaseous and hydraulic media, the preferred application being pneumatics.

The connecting part 1 has an elongated body which is partially hollow on the inside and is handled in a similar way to a screw, which is why it should be referred to as a hollow screw 5. This hollow screw 5 has a cylindrical fastening section 7 provided with an external thread 6 at its front end which projects downwards in Fig. 1. At an axial distance from this fastening section 7 there is a tool engagement section 8 which serves to attach a screwing tool and which is expediently located at the axial end of the hollow screw 5 opposite the fastening section 7. It can form the head of the hollow screw 5 and in the exemplary embodiment is contoured in a polygonal shape so that a wrench can be attached.

Between the fastening section 7 and the tool engagement section 8 there is a further length section of the hollow screw 5, which is referred to as the bearing section 12 due to its function.

A ring- or sleeve-like bearing body 11 is coaxially seated on the bearing section 12. This bearing body belongs to a swivel part 13 which can be rotated by 360° relative to the hollow screw 5, the axis of rotation being aligned with the longitudinal axis 15 of the hollow screw 5. When the

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The bearing body 11 rotates on the bearing section 12 due to the pivoting part 13.

The pivoting part 13 is further provided with means that define a fluid line connection 16 that is oriented transversely with respect to the longitudinal axis 15. In the exemplary embodiment, it has a connection piece 17 that protrudes radially from the bearing body 11 and defines a connection opening 18 into which the aforementioned fluid line 4 can be inserted in a sealed manner. In addition, the connection piece 17 is equipped with fastening means 21 that enable the fluid line 4 to be releasably fixed and that are designed as plug-in connection means in the exemplary embodiment, so that the fluid line connection 16 represents a plug-in connection.

The connecting part 1 can be screwed into the threaded hole 2 of the fluid power component 3 with the fastening section 7 of its hollow screw 5 as shown.

In the screwed state, first fluid channel means 22 formed by the cavity of the hollow screw 5 communicate with a pressure medium channel 23 of the fluid technology component 3 running in extension of the threaded bore 2. The first fluid channel means 22 open out with a first fluid channel opening 24 on the end face of the fastening section 7.

In the interior of the pivoting part 13, second fluid channel means 25 are formed, which are connected to the connection opening 18 and thus to the connected fluid line 4.

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Furthermore, the first and second fluid channel means 22, 25 in the transition region between the hollow screw 5 and the pivoting part 13 are designed such that they are in fluid communication with one another in every rotational position of the pivoting part 13.

By rotating the pivoting part 13, the fluid line connection 16 can be pivoted relative to the longitudinal axis 15 according to the double arrow 14 and positioned as desired along a pivoting angle of 360°. Due to the circumstances just mentioned, a fluid connection is provided between the connection opening 18 and the first fluid channel opening 24 in each pivoting position, which enables the pressure medium, for example compressed air, to flow through the connection part 1 in one direction or the other.

In the embodiment of Figures 1 and 2, the first fluid channel means 22 contain a central fluid channel 26 extending in the longitudinal direction of the hollow screw 5, from which several branch channels 27 branch off radially at the level of the bearing body 11, which are open towards the outer circumference of the bearing section 12. There they open into an annular groove 29 of the bearing section 12, which is open radially outwards, into which the second fluid channel means 25 open in the transition region 28 between the connection piece 17 and the bearing body 11, which are formed here by a single fluid channel running through the connection piece 17 up to the connection opening 18.

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The transition region 28 between the first and second fluid channel means 22, 25 lies axially within the two ends of the bearing body 11, which are each sealed off from the hollow screw 5 by an annular seal 31, 32, so that fluid leakage is prevented. The annular seals 31, 32 expediently lie against the radially inwardly oriented inner surface of the bearing body 11.

Since the connecting part 1 is designed to be screwed into a fluid technology component 3 - the screwing direction 33 is marked by an arrow - it can also be referred to as a screw connection, whereby in the specific case a functional screw connection is present because certain functional means 34 are activated in the course of the two fluid channel means 22, 25, which are able to influence the fluid flow in a predetermined manner. In the exemplary embodiment, these functional means 34 include throttle means 34a for changing the flow cross-section, which are formed here by a throttle screw which is screwed into the central fluid channel 26 from the rear end opposite the first fluid channel opening 24.

On the other hand, the functional means 34 contain non-return means 34b, which are formed here by a rubber-elastic non-return sleeve enclosing the hollow screw 5 and are inserted into a channel arrangement 35 connected in parallel to the branch channels 27. The connecting part 1 thus has the functionality of a throttle check valve, which transmits an unthrottled flow from the connection opening 18 to the first fluid channel opening 24. via the non-return means

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34b is permitted, while in the opposite direction only a flow throttled by the throttling means 34a can occur.

In order to obtain a fluid-tight connection between the connecting part 1 and the fluid power component 3, a separate sealing ring 36 arranged concentrically on the fastening section 7 is provided in the embodiment of Fig. 1 and 2. It has a component sealing surface 37 pointing in the screwing direction 33, with which it rests on the edge area 39 of the fluid power component 3 surrounding the mouth of the threaded hole 2. When the hollow screw 5 is screwed in, it is pressed against this component surface, at the same time deforming radially and thereby also sealingly enclosing the fastening section 7. The axial loading force acting on the sealing ring 36 is applied by an annular loading surface 38, which is placed on a coaxially placed between the sealing ring 36 and the bearing body II on the fastening section 7.

decorated stop ring 42. This simultaneously limits the screw-in depth of the hollow screw 5 by preventing further screwing in of the hollow screw 5 after the maximum axial crush dimension of the sealing ring 36 has been reached.

The stop ring 42 flanks the bearing body 11 of the pivoting part 13 on its side facing the fastening section 7. It has a radially outwardly projecting and preferably circumferential projection 43 which projects in front of the front surface of the^age^kgrpe^s .Jl .;. .Since .the.opposite-

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The bearing body 11 is axially caught as the first stop means 44 are located axially opposite the end face of the bearing body 11, which are preferably an integral part of the hollow screw 5 and can be formed, for example, by an annular radial projection of the same. It sits between the first stop means 44 and the projection 43 of the stop ring 42.

If the stop ring 42 is fixed captively on the hollow screw 5, this simultaneously results in a captively fixed fixation of the pivoting part 13 on the hollow screw 5. The stop ring 42 can, for example, be pressed or glued onto the hollow screw 5.

The first stop means 44 prevent the pivoting part 13 from being pulled off the hollow screw 5 on the side opposite the fastening section 7.

The axial distance between the stop ring 42 and the first

The distance between the stop means 44 is selected such that the bearing body is placed with a certain slight axial play "s" between them. This play "s" is still present even when the hollow screw 5 is screwed firmly into the threaded hole 2 and the stop ring 42 is therefore subjected to an axial load oriented opposite to the screwing direction 33 via the sealing ring 36 placed between them. This in turn guarantees free pivoting movement of the pivot part 13 with respect to the hollow screw 5 even when the latter is screwed firmly in.

In order to maintain the rotational play "s", the stop ring 42 is supported on the outer circumference of the hollow screw 5 in such a way that it cannot move relative to the hollow screw 5 in the opposite direction to the screwing direction. All of the loading forces resulting from tightening the screw connection are thus introduced by the stop ring 42 into the hollow screw 5 and shielded by the bearing body 11 so that the latter is not clamped between the stop ring 42 and the first stop means 44.

To maintain the supporting effect, second stop means 45 are provided on the hollow screw 5 at an axial distance from the front face of the fastening section 7, against which the stop ring 42 placed over the fastening section 7 can rest. The second stop means 45 practically limit the insertion path for the stop ring 42.

According to Fig. 1, the second stop means 45 are formed by an annular radial projection which is concentric with the hollow screw 5 and projects in front of the stop ring 42. This annular projection is preferably an integral component of the hollow screw 5 and is formed directly during its manufacture. It is understood that instead of an annular projection, one or more individual projections distributed over the circumference could also be provided. The annular radial projection, however, has the advantage that with its radially outwardly oriented circumferential surface it can simultaneously function as a pivot bearing surface for the bearing body 11.

The front annular seal 32 provided in this area is carried by the stop ring 42 in the embodiment of Fig. 1. This thus takes on a sealing function in addition to its supporting function.

This is even more pronounced in the embodiment of Fig. 4. There, a stop ring 42 is shown which, in addition to an annular seal 32 cooperating with the bearing body 11, also carries the sealing ring 36 used to seal against the fluid technology component 3, albeit in a modified shape. In this way, both the component sealing surface 37 and the annular sealing surface 46 of the front seal 32 cooperating with the bearing body 11 are part of the stop ring 42. This can even be designed as a composite part consisting of several materials, with the sealing material forming the sealing surfaces 37, 46 being integrally formed on it, for example by injection molding or vulcanization. The stop ring 42 can be made of metal or, preferably, of plastic material.

The embodiment of Fig. 4 differs from that of Figs. 1 and 2 in that the stop ring 42 exerts its supporting effect on the hollow screw 5 by being glued or welded to it. Other mechanical supporting means can therefore be omitted.

In Fig. 5 and 6, however, the second stop means 45 are designed as separate components with respect to the hollow screw 5.

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formed. According to Fig. 5, they are realized in the form of a locking ring 47, which is anchored in a circumferential groove of the hollow screw at the end region of the fastening section 7 assigned to the bearing body 11. It encloses the hollow screw 5 at least for the most part and projects slightly radially beyond its outer circumference so that the stop ring 42 can rest against it.

In the embodiment of Fig. 6, the second stop means 45 are formed by at least one preferably cylindrical locking pin 48 which extends transversely to the longitudinal axis 15, in particular tangentially to the outer circumference of the hollow screw 5 in the transition region between the latter and the stop ring 42. It thus engages with a part of its cross section in the stop ring 42 and with another part of its cross section in an annular groove 49 on the outer circumference of the hollow screw 5.

The embodiment of Fig. 3 is in terms of rotation

bearing of the bearing body 11 and the design and attachment of the stop ring 42 are identical to the design of Fig. 1 and 2. The only differences here are that the fluid channel means 22, 25 do not contain any functional means, so that the connecting part 1 is a pure flow guide part. In addition, the connecting part of Fig. 3 shows another design of the fluid line connection 16, which is designed here as a screw connection.

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What all embodiments have in common is that the fastening section 7 has a circular-cylindrical contour on the outside and has a cylindrical external thread 6, which can be designed as a pipe thread (e.g. G 1/8", G 1/4",...) or metric thread.

The connecting part could also have a shape other than the L-shaped one shown and could, for example, be designed as a T-piece, the swivel part 13 of which has two fluid line connections.

The connecting part is characterized by a very short overall length in the longitudinal direction of the hollow screw 5. The bearing body 11 can protrude very close to the fluid technology component 4 because the axial dimensions of the stop ring are very small and the tool engagement section 8 is located on the axial side of the bearing body 11 opposite the fastening section 7.

The functionality of the example connector can be briefly summarized as follows:

The hollow screw 5 is screwed into the threaded hole 2 with the fastening section 7 and is tightened firmly using a screwing tool that can be attached to the tool engagement section located above the swivel part 13. The stop ring 42 is axially clamped between the second stop means 45 and the fluid technology component 3 or the sealing ring 6 that is still in between. The axial forces introduced against the screwing direction ^33 act in this way,

for example, via the surface of the second stop means designed as a ring projection facing the stop ring 42
45, onto the hollow screw 5. Due to the unaffected axial play between the stop ring 42 and the swivel part 13, the latter can be rotated freely.

Claims (21)

1. Connection part for fluid lines, with a hollow screw ( 5 ) onto which a swivel part ( 13 ) having at least one fluid line connection ( 16 ) is rotatably mounted and which has at the front end a fastening section ( 7 ) provided with an external thread ( 6 ) for screwing in a screwing direction ( 33 ) into a component ( 3 ) to be fitted with the connection part ( 1 ), wherein first stop means ( 44 ) are provided on the hollow screw ( 5 ) for preventing an axial movement of the swivel part ( 13 ) relative to the hollow screw ( 5 ) opposite to the screwing direction ( 33 ), and wherein a ring flanking the swivel part ( 13 ) on the side facing the fastening section ( 7 ) is coaxially mounted on the hollow screw ( 5 ), which ring, when the fastening section (13) is screwed into a component ( 3 ), 7 ) is subjected to an axial load oriented counter to the screwing direction ( 23 ) by this component ( 3 ), characterized in that the ring is designed as a stop ring ( 42 ) which is supported on the outer circumference of the hollow screw ( 5 ) in an axially immovable manner with respect to the latter counter to the screwing direction ( 33 ). 2. Connecting part according to claim 1, characterized in that second stop means ( 45 ) are provided on the hollow screw ( 5 ) at an axial distance from the front side of the fastening section ( 7 ), on which the stop ring ( 42 ) can be supported against the screwing direction ( 33 ). 3. Connecting part according to claim 2, characterized in that the second stop means ( 45 ) are formed by at least one radial projection of the hollow screw ( 5 ), against which the stop ring ( 42 ) can rest from the side of the fastening section ( 7 ). 4. Connecting part according to claim 2 or 3, characterized in that the second stop means ( 45 ) are formed by an annular radial projection concentric with the hollow screw ( 5 ). 5. Connecting part according to one of claims 2 to 4, characterized in that the second stop means ( 45 ) are integrally connected to the hollow screw ( 5 ). 6. Connecting part according to one of claims 2 to 4, characterized in that the second stop means ( 45 ) are formed separately with respect to the hollow screw ( 5 ). 7. Connecting part according to claim 6, characterized in that the second stop means ( 45 ) are formed by a locking ring ( 47 ) anchored to the hollow screw ( 5 ) and at least largely enclosing it. 8. Connecting part according to claim 6, characterized in that the second stop means ( 45 ) are formed by at least one locking pin ( 48 ) extending transversely to the longitudinal axis ( 15 ) of the hollow screw ( 5 ). 9. Connecting part according to claim 1, characterized in that the stop ring ( 42 ) is glued or welded to the hollow screw ( 5 ) to maintain the supporting effect. 10. Connecting part according to one of claims 1 to 9, characterized in that the stop ring ( 42 ) is held captive on the hollow screw ( 5 ) even when the fastening section ( 7 ) is not screwed into a component ( 3 ). 11. Connecting part according to one of claims 1 to 10, characterized in that the stop ring ( 42 ) is fixed in a press fit on the hollow screw ( 5 ). 12. Connecting part according to one of claims 1 to 11, characterized in that the stop ring ( 42 ) coaxially carries an annular sealing surface ( 46 ) which cooperates sealingly with the pivoting part ( 13 ). 13. Connecting part according to one of claims 1 to 12, characterized in that the stop ring ( 42 ) coaxially carries an annular component sealing surface ( 37) facing the end face of the fastening section (7 ) and sealingly cooperating with the relevant component ( 3 ) when the fastening section ( 7 ) is screwed in. 14. Connecting part according to claim 12 or 13, characterized in that the respective sealing surface ( 46 , 37 ) is provided on an annular seal ( 32 , 36 ) anchored on the stop ring ( 42 ). 15. Connecting part according to one of claims 1 to 12, characterized in that a separate sealing ring ( 36 ) is arranged in front of the stop ring ( 42 ) on the side facing the front side of the fastening section ( 7 ), which carries a component sealing surface ( 37 ) which cooperates sealingly with the relevant component ( 3 ) when the fastening section ( 7 ) is screwed in. 16. Connecting part according to one of claims 1 to 15, characterized in that the external thread ( 6 ) of the fastening section ( 7 ) is designed as a cylindrical and preferably as a metric thread or pipe thread. 17. Connecting part according to one of claims 1 to 16, characterized in that a tool engagement section ( 8 ) enabling the attachment of a screwing tool is provided on the hollow screw ( 5 ) on the side of the pivoting part ( 13 ) opposite the fastening section ( 7 ). 18. Connecting part according to one of claims 1 to 17, characterized by first fluid channel means ( 22 ) formed by the cavity of the hollow screw ( 5 ) and opening out to the front side of the fastening section ( 7 ), which, regardless of the current pivoting position of the fluid line connection ( 16 ), are connected to second fluid channel means ( 25 ) running in the pivoting part ( 13 ) and leading to the fluid line connection ( 16 ). 19. Connecting part according to claim 18, characterized in that suitable functional means ( 34 ) for influencing the fluid flow are inserted into the course of the first and/or second fluid channel means ( 22 , 25 ), for example throttle and/or non-return means ( 34a , 34b ). 20. Connecting part according to one of claims 1 to 19, characterized in that the fluid line connection ( 16 ) is designed as a plug connection or as a screw connection. 21. Connecting part according to one of claims 1 to 20, characterized in that the pivoting part ( 13 ) is held captively on the hollow screw ( 5 ) by the stop ring ( 42 ).