Line Connector and Line Set for Fluid Media

Abstract

The present invention relates to a line connector (1) having two mutually separate flow paths for two fluid media, specifically one for a functional medium, in particular for a urea-water solution in an SCR catalytic converter system of a motor vehicle, and another for a temperature control medium for controlling the temperature of the functional medium. The line connector (1) is composed of a connector body (2) having at least three line connections, specifically at least a first connection (4) for a first line which conducts the functional medium, a second connection (6) for a second line which conducts the temperature control medium, and a third connection (8), which is designed as a double connection, for a double line (10) which is composed of an inner line (12) and an outer line (14) substantially coaxially surrounding said inner line (12). The third connection (8) has an inner connecting element (16) with an inner passage (24) and an outer connecting element (18) with an outer passage (26). The connector body (2) is formed in its interior such that the first and second connections (4, 6) merge separately from one another into the inner and outer passages (24, 26), respectively, of the third connection (8). The invention also relates to a line set comprising a line connector (1) according to the invention and at least one connected line for a fluid medium.

Description

The present invention relates to a line connector having two mutually separate flow paths for two fluid media, specifically one for a functional medium, in particular for a urea-water solution in an SCR catalytic converter system of a motor vehicle, and another for a temperature control medium for controlling the temperature of the functional medium.

The invention also relates to a line set comprising a line connector of said type and at least one connected line.

In motor vehicle engineering, in particular in diesel engines, use is made in part of so-called SCR catalytic converters (SCR=selective catalytic reduction), with an aqueous, for example a 32.5% urea solution, being used as a NOx reduction additive. Here, it is a known problem that a urea-water solution of said type, on account of its freezing point of approximately −11° C., requires special measures to prevent freezing in the case of correspondingly low ambient temperatures in order to ensure the function of the SCR catalytic converter even at low ambient temperatures.

EP 1 818 588 A1, for example, thus describes a hose assembly for conducting a urea-water solution, said hose assembly comprising a connector and a hose, with a temperature control means in the form of an electric heat conductor or a second, inner hose for conducting a fluid temperature control medium running coaxially or eccentrically through the cavity of the hose. The temperature control means which runs in the longitudinal direction through the outer hose also runs through the entire connector and, opposite, is guided out of an outlet such that sealing is required in the leadthrough region. A connection of the lines, in particular in the case of the temperature control line, is extremely cumbersome.

The object on which the present invention is based is that of improving a line connector of the type described in the introduction such that it is firstly of simple structural design and can be produced in a simple and economical manner and it secondly ensures good use characteristics, in particular with regard to as simple and fast a connection as possible of the lines required for the two media.

This is achieved according to the invention by means of a line connector according to claim 1. A line set according to the invention is the subject matter of claim 9. The respective dependent claims relate to advantageous refinements.

The line connector according to the invention will be explained on the basis of a plurality of exemplary embodiments illustrated in the drawing, in which:

FIG. 1 shows a longitudinal section through a line connector according to the invention in a first embodiment,

FIG. 2 shows a view in the arrow direction II as per FIG. 1,

FIG. 3 shows a view in the arrow direction III as per FIG. 1,

FIG. 4 shows a longitudinal section through a second embodiment of the line connector according to the invention with a connected double line for a functional medium and a temperature control medium, and

FIG. 5 shows a design variant of FIG. 4 in a corresponding longitudinal sectional illustration.

In the different figures of the drawing, identical parts are always provided with the same reference numerals and are therefore generally also described only once in each case.

A line connector 1 according to the invention is used in conjunction with lines for a fluid functional medium which is at risk of freezing, with the functional medium being temperature-controlled, in particular heated, though said functional medium may if appropriate also be cooled, by means of a temperature control medium. Here, the line connector 1 serves firstly for conducting the functional medium and secondly for supplying or discharging the temperature control medium, which preferably circulates in a circuit.

In a preferred use of the line connector 1, the functional medium is a urea-water solution in an SCR catalytic converter of a motor vehicle, with it being possible for the engine coolant (cooling water), for example, to be used as temperature control medium.

The line connector 1 according to the invention is composed of a connector body 2 having (at least) three line connections, specifically a first connection 4 for a first line (not illustrated) which conducts the functional medium, a second connection 6 for a second line (likewise not illustrated) which conducts a fluid temperature control medium, and a third connection 8 for a coaxial double line 10 (see FIGS. 4 and 5) which is composed of an inner line 12 and an outer line 14 substantially coaxially surrounding said inner line 12. For this purpose, the third connection 8 is designed in particular as a double connecting piece with an inner connecting piece 16 and an outer connecting piece 18, with it being possible for the connecting pieces 16, 18 to be arranged coaxially or with a slight parallel offset. The inner connecting piece 16 preferably extends axially beyond the outer connecting piece 18 with a certain projecting length X. The inner connecting piece 16 is expediently formed with a receptacle 20 for plugging in the inner line 12, with it being possible for the line 12 to be fastened preferably cohesively, specifically in particular by means of laser welding, for which purpose the inner connecting piece 16 is composed of a laser-transparent material at least in the region of the receptacle 20 and of the projecting length X. The outer connecting piece 18 is preferably formed in the manner of a conventional hose or pipe connecting piece with an external mandrel profile 22, composed of one or more holding edges, for plugging on the outer line 14. The outer line 14 may, as illustrated by way of example in FIGS. 4 and 5—be formed by a so-called corrugated pipe. The outer line 14 may fundamentally also—alternatively or additionally—be fastened cohesively, in particular by means of laser welding.

Here, the third connection 8 furthermore has an inner passage 24 in the form of an axial central duct to the transition into the inner connecting piece 16 and a duct 12a of the inner line 12 and also an outer passage 26 to the transition into an annular duct 14a between the inner line 12 and the outer line 14. The inner passage 24 therefore opens out axially into the receptacle 20 of the inner connecting piece 16, while the outer passage 26 opens outward into an end region, radially adjacent to the inner connecting piece 16, of the outer connecting piece 18. The connector body 2 is formed in its interior such that the first and second connections 4, 6 merge separately from one another into the inner and outer passages 24 and 26, respectively, of the third connection 8. In physical terms, in the illustrated exemplary embodiments, the first connection 4 merges into the inner passage 24, while the second connection 6 is connected to the outer passage 26.

Here, the functional medium whose temperature is to be controlled is preferably supplied or discharged via the first connection 4, such that said functional medium flows through the duct 12a of the inner line 12. A temperature control medium, in particular engine coolant, is supplied or discharged via the second connection 6, such that said temperature control medium flows through the annular duct 14a between the inner line 12 and outer line 14. The temperature control medium accordingly forms a jacket for the functional medium. In this way, optimum temperature control of the functional medium within the inner line 12, and effective protection against low ambient temperatures, are provided.

In the preferred embodiments illustrated, the first connection 4 and the second connection 6 are formed as constituent parts of plug systems for the fast and releasable plugged connection of the respective line, specifically in particular in each case as a receptacle 28 with holding means 30 (see FIGS. 4 and 5) for a line-side plug part (not illustrated) to be plugged in. Furthermore, seal elements 32 may be arranged within the receptacle 28.

Each connection 4, 6, 8 has a connection axis 4a, 6a, 8a, with it being possible for the connections 4, 6, 8 to be arranged and configured in practically any desired manner with regard to the relative alignment of their connection axes. In the embodiment according to FIGS. 1 to 3, for example, the connection axis 4a of the first connection 4 runs perpendicular to the two connection axes 6a, 8a of the second and third connections 6, 8. The second and third connections 6, 8 may be arranged coaxially, that is to say with axes 6a, 8a which merge flush into one another. In the illustrated embodiment, however, the two connector axes 6a and 8a are offset slightly in parallel.

In the embodiment according to FIG. 4, firstly the first and second connections 4, 6 are arranged at right angles with respect to one another with regard to their connection axes. Furthermore, the first and third connections 4, 8 are also aligned at right angles to one another. The second connection 6 is arranged parallel and offset with respect to the third connection 8.

Finally, in the exemplary embodiment according to FIG. 5, the first connection 4 merges coaxially into the third connection 8, while the second connection 6 is aligned with its connection axis 6a perpendicular to the axes 4a, 8a.

Certain design features of the individual embodiments will be explained below.

In the embodiment according to FIGS. 1 to 3, the connector body 2 is formed as a substantially single-piece molded part, in particular from a plastic material but if appropriate also from metal. This can be seen in particular from the sectional view in FIG. 1. Here, the outer passage 26, which adjoins the receptacle 28 of the second connection 6 in the direction of the third connection 8, is formed as an eccentric duct with an approximately sickle-shaped cross section, in this regard, see in particular FIGS. 2 and 3. Said design has the advantage that the connector body 2 can be of massive design, and therefore very stable, in a region diametrically opposite the outer passage 26 (see FIG. 1), which also ensures high stability in the region of the third connection 8, and in particular of the inner connecting piece 16, for absorbing lateral forces exerted via the respective line. It is also advantageous that, as a result of the eccentric arrangement of the duct of the passage 26, at least one further connection may easily be provided as a transverse branch for the functional medium in a region situated outside the duct in the circumferential direction, without said further connection having to intersect the passage 26 or the eccentric duct. The inner passage 24 is designed as an axial duct which merges at right angles into the first connection 4 and the receptacle 28 thereof.

In the exemplary embodiments according to FIGS. 4 and 5, the connector body 2 is composed of originally a plurality of (at least two) parts which are joined together in particular cohesively. The connector body 2 is thus composed of an outer connector housing 34 and (at least) one insert part 36 (FIG. 4) or (at least) two insert parts 36, 38 (FIG. 5). The/each insert part 36, 38 is cohesively connected at least in regions to the connector housing 34. The first insert part 36 preferably forms the first connection 4 and is inserted into the connector housing 34 in such a way as to be circumferentially surrounded by an annular chamber 40. The second connection 6 opens out into said annular chamber 40, with the annular chamber 40 being connected by means of ducts 42 to a plurality of ducts which form the outer passage 26. Here, the ducts 42 or the outer passage 26 are constituent parts of the connector housing 34 (FIG. 4), which is formed in one piece in said region, or of the second insert part 38 (FIG. 5). The first insert part 36 may be plugged in axially, that is to say in the direction of the connection axis 4a, and then sealingly connected to the connector housing 34 in a circumferential region 44 in a cohesive manner, in particular by means of laser welding. This also applies to the embodiment according to FIG. 5, in which it is however also possible for the second insert part 38 to be plugged axially into the connector housing 34. Here, the two insert parts 36, 38 are plugged together and connected in said region 46 either likewise in a cohesive manner, in particular by means of laser welding, or by means of a seal (O ring). The second connection 6 or the receptacle part thereof with the receptacle 28 is preferably formed in one piece with the connector housing 34.

The invention is not restricted to the illustrated and described exemplary embodiments, but rather also encompasses all equivalent embodiments within the context of the invention. Furthermore, the invention has up to now also not been restricted to the combination of features defined in the respective independent claim, but rather may also be defined by any desired other combination of certain features of all the individual features disclosed overall. This means that basically practically any individual feature of the respective independent claim may be omitted or replaced with at least one individual feature disclosed at some other point of the application. In this respect, the claims are to be understood merely as a first attempted formulation for an invention.

Claims

1. A line connector (1) having two mutually separate flow paths for two fluid media, specifically one for a functional medium, in particular for a urea-water solution in an SCR catalytic converter system of a motor vehicle, and another for a temperature control medium for controlling the temperature of the functional medium, characterized by a connector body (2) having at least three line connections, specifically at least a first connection (4) for a first line which conducts the functional medium, a second connection (6) for a second line which conducts the temperature control medium, and a third connection (8), which is designed as a double connection, for a double line (10) which is composed of an inner line (12) and an outer line (14) substantially coaxially surrounding said inner line (12), for which purpose the third connection (8) has an inner connecting element (16) with an inner passage (24) and an outer connecting element (18) with an outer passage (26), and with the connector body (2) being formed in its interior such that the first and second connections (4, 6) merge separately from one another into the inner and outer passages (24, 26), respectively, of the third connection (8).

2. The line connector as claimed in claim 1, characterized in that the third connection (8) is designed as an in particular coaxial double connecting piece with an inner connecting piece (16) and an outer connecting piece (18), with the inner connecting piece (16) preferably extending axially beyond the outer connecting piece (18) with a certain projecting length (X).

3. The line connector as claimed in claim 2, characterized in that the inner connecting piece (16) is formed with a receptacle (20) for plugging in the inner line (12), with it being possible for the line (12) to be fastened preferably cohesively and in particular by means of laser welding, for which purpose the inner connecting piece (16) is preferably formed from a laser-transparent material at least in the region of the receptacle (20).

4. The line connector as claimed in claim 2 or 3, characterized in that the outer connecting piece (18) is formed with an outer mandrel profile (22) for plugging on the outer line (14).

5. The line connector as claimed in one of claims 1 to 4, characterized in that the first connection (4) and/or the second connection (6) are/is designed as a plug-type system for the fast and releasable plugged connection of the respective line.

6. The line connector as claimed in one of claims 1 to 5, characterized in that the connector body (2) is formed as a substantially single-piece molded part.

7. The line connector as claimed in one of claims 1 to 5, characterized in that the connector body (2) is composed of a plurality of parts which are joined together, specifically in particular of a connector housing (34) and at least one insert part (36, 38).

8. The line connector as claimed in claim 7, characterized in that two insert parts (36, 38) are connected at least in regions to the connector housing (34) and preferably also in regions to one another with circumferential sealing.

9. A line set comprising a line connector (1) as claimed in one of the preceding claims and at least one connected line for a fluid medium.

10. The line set as claimed in claim 9, characterized in that a double line (10) composed of two in particular coaxial lines (12, 14) is connected to the third connection (8), which is designed as a double connecting piece, of the line connector (1).

11. The line set as claimed in claim 9 or 10, characterized in that a line which conducts the functional medium whose temperature is to be controlled is or can be connected to the first connection (4) of the line connector (1), while a line which conducts the temperature control medium is or can be connected to the second connection (6).