DE29621046U1 - Connector for plastic pipes - Google Patents

Description

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03 December 1996 &idigr; I Li. . &idigr;

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DESCRIPTION

Connection plug for plastic pipes

TECHNICAL AREA

The present invention relates to a connector device for plastic pipelines, with a connector device with a first external thread and an annular space into which a pipe end can be inserted from the outside until it rests against a stop, a screw-on housing with an internal thread for screwing onto the first external thread of the connector device, first sealing means for sealing between the outer wall of the pipe and the inner wall of the screw-on housing and second sealing means for sealing the outer wall of the connector device with the inner wall of the screw-on housing.

Such devices, often referred to as plug connections, are installed in particular in the area of compressed air brake systems. These devices must withstand pressures of up to 20 bar (including safety margin). The aim is to achieve permanently reliable tightness and easy connection.

Such plug connections are also used, for example, to connect pressure lines to pressure vessels or valve housings. The plug connection with the support sleeve arranged in it is usually screwed to a connection and then the pipe is inserted into the connection housing. This enables a very simple pipe plug connection.

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STATE OF THE ART

A connection fitting is known in which a taper pin is loosely inserted into a connection element and is fixed in the axial direction when the connection element is screwed onto the connection piece, whereby the reaction force of the thread preload is transmitted via the taper pin. A soft seal is used to seal the screw connection, which is arranged between the front face of the connection piece and the contact surfaces formed by the connection element and the taper pin. In addition, there is a support sleeve that guides the pipe end when it is inserted into the connection fitting. In this connection fitting, the clamping of the soft seal depends on the manufacturing tolerances of the connection piece, the taper pin and the components of the connection element, since the distance between the front face and the contact surfaces is determined by the dimensions of these parts. The soft seal is also supported on the threads of the internal thread and external thread, which may be necessary.

This can result in leaks. A connection fitting of this type is only suitable for connection to a so-called cone connection, which is normally standardized.

A generic connection fitting for plastic pipes is characterized by the fact that a taper pin is attached to a sleeve that is sealed against a receiving bore and is fixed in a connection element in such a way that when the connection element is unscrewed from the connection piece, the axial movement of the internal thread is transferred to the taper pin and that the taper pin has a sealing ring in a recess that can be pressed against the wall of the taper bore. The sleeve is connected to the connection element in a captive manner. This connection fitting is also only suitable for creating a connection to the known cone connection.

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DESCRIPTION OF THE INVENTION

Based on the above-mentioned prior art, the present invention is based on the task or technical problem of providing a connection plug device which enables variable application possibilities for different connection types, but at the same time ensures long-term functional reliability, economic usability and structural simplicity and also enables the use of conventionally standardized connection pieces.

The connection plug device according to the invention is given by the features of independent claim 1. Advantageous embodiments and further developments are the subject of the dependent claims.

The connection plug device according to the invention of the type mentioned at the outset is therefore characterized in that the connection device is designed as a cone connection unit known per se with an inner cone and the first external thread and as a separate sealing and holding adapter unit, whereby the adapter unit has a corresponding outer cone with sealing means and has a sealing and holding groove on the outside with a locking lip positioned in front against the connection direction, such that the adapter unit can be inserted into the screw-on housing in a sealingly releasable manner by the second sealing means releasably engaging in the sealing and holding groove during the insertion process, and the screw-on housing with the inserted adapter unit can be screwed onto the cone connection unit in a sealingly releasable manner, or the connection device is designed as a screw-in housing with a further external thread and has a sealing and holding groove on the outside with a locking lip positioned in front against the plug-on direction, such that the second sealing means can be inserted into the screw-on housing in a sealingly releasable manner with the second sealing means releasably engaging in the sealing and holding groove during the insertion process, and the screw-on housing with the inserted adapter unit can be screwed onto the cone connection unit in a sealingly releasable manner, or the connection device is designed as a screw-in housing with a further external thread and has a sealing and holding groove on the outside with a locking lip positioned in front against the plug-on direction, such that the second sealing means

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The screwed-on housing snaps into the sealing and retaining groove in a sealing and releasable manner.

In a first preferred embodiment, the annular space in the adapter unit is designed as an annular bore.

A further preferred embodiment with regard to the second alternative connection option is characterized in that the annular space in the screw-in housing is formed by a blind hole and a support sleeve arranged in the hole with a reduced diameter compared to the blind hole.

An embodiment that is particularly favorable in terms of production and ensures long-term functionality is characterized by the fact that the bearing of the support sleeve in the blind hole is designed as a fit or press fit bearing.

A particularly advantageous development of the connection plug device for pipes according to the invention is characterized in that the sealing and holding groove with a grid lip positioned in front against the connection direction is present on the outside in the open end area of the annular space.

According to the invention, the connection plug device can be used as a detachable combination plug device in one variant as a screw-on plug connection or in one variant as a screw-in plug connection. To implement this combination, only three components are required, namely the screw-on housing, the sealing and retaining adapter and the screw-in housing. In both versions, the plug connection can be released via the locking lip in conjunction with the sealing and retaining groove. The sealing and retaining ring takes over the screw-on version, i.e. in conjunction with the sealing and

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03 December 1996

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Retaining adapter, both the sealing function and the holding function for the sealing and holding adapter. With the screw-in plug connection, the sealing and retaining ring takes over the sealing function for the screw-on housing.

Brass is the preferred material for the existing components.

Further embodiments and advantages of the invention result from the features further listed in the claims and from the exemplary embodiments given below. The features of the claims can be combined with one another in any way, provided they are not obviously mutually exclusive.

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BRIEF DESCRIPTION OF THE DRAWING

The invention as well as advantageous embodiments and further developments of the same are described below with reference to the

The examples shown in the drawing are described in more detail and er-20

The features shown in the description and the drawing can be used individually or in combination in accordance with the invention. They show:

25

Fig. 1 schematic exploded view of a connection plug device designed as a screw-on connection with a conical connection, a sealing and holding adapter and a screw-on housing, with a sectional view above the system line and below the

30

System line a view representation is selected,

Fig. 2 schematic representation of the device according to Fig. 1 in connected state,

35

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Fig. 3 schematic exploded view of a connection plug device, designed as a screw-in plug connection with a screw-in housing and a screw-on housing, where a longitudinal section is selected above the system line and a view is selected below the system line and

Fig. 4 schematic representation of the connection plug device

as shown in Fig. 3 when connected. 10

WAYS TO CARRY OUT THE INVENTION

In Fig. 1, a connection plug device 50.1 for a pipe 4 is shown in an exploded state, which consists of a two-part connection unit 30.1 and a screw-on housing 1. The connection direction is shown schematically in the figures by an arrow A.

The connection device 30.1 consists of a standardized DIN 24° cone connection unit 15, which has a first external thread 32 and in the front area facing the screw-on housing 1 an internal cone 38, which widens in the opposite direction to the connection direction A. The second component of the connection device 30.1 is a sealing and holding adapter 23 which can be detachably snapped into the interior of the screw-on housing 1.

The adapter 2 has an open annular space 34, seen from the connection direction A, which is formed by an annular bore. On the inside of the annular space 34 there is a hollow support sleeve 9, the diameter of which is slightly smaller than the diameter of the pipe 4. The annular space 34 has a pipe stop 14 in its base area up to which the pipe 4 can be inserted into the annular space 34 in the connection direction when connected.

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On the outside, a raster lip 6 is formed on the adapter 2 from the open end area of the annular space 34, which is followed by a sealing and retaining groove 5 as seen in connection direction A. In the further
In the connection direction A, the outer contour of the adapter 2 is designed as an outer cone 7, specifically in the connection direction A with a decreasing diameter, such that the outer cone 7 of the adapter 2 comes into contact with the inner cone 38 of the cone unit 15 in the connected state. Finally, there is a groove 42 in the outer surface of the outer cone 7,

within which a conical ring 8 is arranged for sealing purposes
is.

On the right front edge area, the screw-on housing has 1
a pipe guide bore 19, the inner diameter of which is only slightly larger than the outer diameter of the pipe 4.

The screw-on housing 1 has on the inside in the connection direction
A seen from the right, first a step groove 44,
within which a sealing and dirt ring 13 with
relatively large diameter and directly adjacent to it a sealing ring 12 with a smaller diameter is arranged.

In the further course seen in connection direction A, the inner wall of the connection housing 1 has conically widening

clamping surfaces 17. In this conical clamping surface area
17 is a cutting ring 3 with cutting teeth 16 arranged,
whose task is to keep the pipe in connected
This is done by securing the
ensures that the cutting ring 3 is slotted and

is movable in the screw-on housing 1. By inserting the
The cutting ring then expands when the plastic pipe 4 is cut.
After reaching the insertion depth at the pipe stop 14, the cutting teeth 16 clamp the plastic pipe firmly. When pressure is applied or by pulling on the pipe, the cutting ring 3 is clamped over the conical clamping surfaces 17, the cutting

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teeth 16 cut into the outer wall of the tube 4 and secure its position.

Directly adjacent to the cutting ring 30, as seen in the connection direction A, there is another groove 46 on the inside, in which another sealing ring 11 is arranged.

In the further course of the inner wall of the screw-on housing 1 in the connection direction A, a sealing and retaining ring 10 is arranged at a distance from the sealing ring 11 in a further groove 48, wherein this sealing and retaining ring 10 slides over the grid lip 6 when the sealing and retaining adapter 2 is inserted into the screw-on housing 1 and releasably engages in the sealing and retaining groove 5 of the adapter 2.

Finally, further along the inner wall of the screw-on housing 1 there is an internal thread 36 that can be screwed onto the external thread 32 of the cone connection unit 15. Between the sealing and retaining ring 10 and the internal thread 36 there is also a radially extending internal stop surface 20 that comes to a stop with a corresponding counter stop surface 49 on the sealing and retaining adapter 2 when the screw-on housing 1 is screwed on.

On the outside, the screw-on housing 1 has a hexagonal contour 47 at the level of the internal thread 36, so that a tool can be used for screwing it on in a simple manner.

As already mentioned, when making the connection, the sealing and retaining adapter 2 is first inserted into the interior of the screw-on housing 1 and is detachably secured within the screw-on housing 1 by the locking of the sealing and retaining ring 10 in conjunction with the inner stop surface 20 and

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03 December 1996 IZS. *&idigr; * i &idigr;&idigr;&iacgr;·.

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the counter stop surface 4 9 is locked in its position and a tight connection is achieved between the inner wall of the screw-on housing 1 and the outer wall of the adapter 2. In this state, the screw-on housing 1 with the sealing and holding adapter 2 is screwed onto the cone connection unit 15. The conical outer contour 7 of the sealing and holding adapter 2 is pressed into the inner cone 38 of the cone connection unit 15, whereby the tightness is ensured by pressing the cone ring 8 together.

If the screw-on housing 1 is screwed onto the cone connection unit 15, the pipe 4 can be connected in a simple manner in the connection direction A. To do this, the pipe 4 is inserted through the pipe guide hole 19 into the interior of the screw-on housing 10. The pipe 4 is guided further over the support sleeve 9, penetrates into the annular space 34 up to the pipe stop 14. The rings 11, 12, 13 are placed in a sealing manner against the outer contour of the pipe 4. The cutting ring 3 with its cutting teeth 16 secures the pipe 4 against being pulled out.

In the version shown, the screw-on housing 1 can be used for a screw-on plug connection in conjunction with the sealing and holding adapter 2. The plug connection can be released via the locking lip β in conjunction with the sealing and holding groove 5. In this screw-on version, the sealing and holding ring 10 takes on both the sealing function and the holding function for the sealing and holding adapter 2.

Fig. 3 shows the second version of how the same screw-on housing 1 can be used for a screw-in plug connection with a screw-in housing 21.

The screw-on housing 1 is identical to the screw-on housing 1 in Fig. 1 and 2. The same components have the same reference numerals and are not explained again. -10-

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The connection device 50.2 according to Fig. 3 and 4 has, as already mentioned, the screw-on housing 1 and a connection device 30.1 which is designed as a screw-in housing 21. Seen in the connection direction A, the screw-in housing 21 initially has essentially the same outer contours as the adapter unit 2 according to Fig. 1. Here too, an annular space 34 is present, whereby this annular space 34 is created by the fact that the screw-in housing initially has a blind hole stepped bore in which a hollow support sleeve 23 is inserted up to a stop 27. From this stop 27 the stepped bore is designed as a press fit bearing for the support sleeve 23.

Just like the sealing and holding adapter 2, the screw-in housing 21 has, on the outside, as seen from the open end of the annular space 34 in the connection direction A, a first raster lip 6 with an adjoining sealing and holding groove 5. As it continues in the connection direction A, the outer contour of the screw-in housing 21 has a first external thread 32, which is designed so that the internal thread 36 of the screw-on housing 1 can be screwed on. As the outer contour continues in the connection direction A, the screw-in housing 21 has a protruding hexagonal contour 31 and, adjoining it, a further external thread 40, via which the screw-in housing 21 can be connected to an internal thread (not shown) of a pressure vessel.

For sealing purposes, the left front side of the protruding hexagon cone in Fig. 3 has an annular screw-in seal 22. On the front side of the protruding hexagon 31 opposite the connection direction A there is a stop surface 28 which, when the screw-on housing 1 is screwed on, comes into contact with the left front external stop surface 24 of the screw-on housing 1.

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The sealing and locking function with respect to the inserted pipe 4 is ensured in the same way when the screw-on housing 1 is screwed onto the screw-in housing 21 as in the design variant according to Figs. 1 and 2.

With this type of connection, the plug connection can also be released via the locking lip 6 in conjunction with the sealing and retaining groove. In the screw-in plug connection solution shown, the sealing and retaining ring 10 takes over the sealing function for the screw-in housing 21. According to the invention, it is thus possible to use one and the same screw-on housing 1 for a screw-on plug connection in conjunction with a sealing and retaining adapter 2 and for a screw-in plug connection with a screw-in housing 21. The plug connection is designed to be removable in both versions.

Claims (1)

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EXPECTATIONS 01) Connection plug device (50.1, 50.2) for pipes (4), in particular plastic pipes, with — a connecting device (30.1, 30.2) with
-- a first external thread (32) and - an annular space (34) into which a pipe end can be inserted from the outside until it rests against a stop (14, 25), - a screw-on housing (1) with -- an internal thread (36) for screwing onto the first external thread (32) of the connecting device (30.1, 30.2), — first sealing means (11, 12, 13) for sealing between
the outer wall of the pipe (4) and the inner wall of the screw-on housing (1) and - second sealing means (10) for sealing the outer wall of the connection device (30,1 30,2) with the inner wall of the screw-on housing (1), characterized in that
the connection device (30.1) as a known cone connection unit (15) with inner cone (38) and the
first external thread (32) and as a separate sealing and holder adapter unit (2), wherein the adapter unit (2) has a corresponding outer cone (7) with
sealing means (8) and has a sealing and retaining groove (5) on the outside with a locking lip (6) positioned opposite to the connection direction (A), such that the adapter unit
(2) Sealingly removable into the screw-on housing
(1) can be inserted by releasably inserting the second sealing means (10) into the sealing and retaining groove during the insertion process
(5) engage, and the screw-on housing (1) with inserted adapter unit (2) can be screwed onto the cone connection unit (15) in a sealing manner, or &mdash; the connection device (30.2) as a screw-in housing (21) is formed with a further external thread (40) and on the outside a sealing and retaining groove (5) with opposite 03 December 1996 &bull; e < -2- 05 10 the plug-on direction (A) in front of a locking lip (6) such that the second sealing means (10) snap into the sealing and retaining groove (5) in a sealingly releasable manner when the screw-on housing (1) is screwed on. 02) Device according to claim 1, characterized in that the annular space (32) in the adapter unit (2) is designed as an annular bore. 03) Device according to claim 1, characterized in that the annular space (34) in the screw-in housing (21) is formed by a blind hole and a support sleeve (23) with a reduced diameter arranged in the blind hole. 20 04) Device according to claim 3, characterized in that the bearing of the support sleeve (23) in the blind hole is designed as a fitting or press-fit bearing. 05) Device according to one or more of the preceding claims,
characterized in that the sealing and retaining groove (5) with a grid lip (6) positioned in front opposite to the connection direction (A) is present on the outside in the open end region of the annular space (34). 06) Device according to claim 2, characterized in that a support sleeve (9) is provided adjacent to the annular space (34). 35 RRCO-O2gDE 03 December 1996 «**· J *! .**. .*·.. -3- 07) Device according to claim 3 and/or 4, characterized in that the blind hole is designed as a stepped hole with a stop surface (27). 05