DE102007016789A1 - Heatable connector piece for reducing agent supply system in internal combustion engine in motor vehicle, has heating rod extending in channel and with outer conductor i.e. V4A stainless steel tube, surrounded by inner conductor - Google Patents

Abstract

The piece (1) has openings (2, 3) connected by a fluid channel (4), and an electrically heatable heating rod (6) extending in the fluid channel. The heating rod has a tubular outer conductor i.e. V4A stainless steel tube, surrounded by an inner conductor, where the outer conductor forms a heating element. A connector line is provided with an electrical contact point to conduct heating current to a heating device of fluid lines attached to the opening (3). The heating rod is switched in series with the contact point and inserted into a metal sleeve. An independent claim is also included for a reducing agent supply system comprising a reducing agent tank.

Description

The The invention relates to a fitting for a Fluid conduit having first and second openings, which are connected by a fluid channel.

One such connector may serve, for example, to connect two sections of a fluid line or a fluid line to a pump or the like Device to connect. Such fittings especially for reducing agent supply systems for an exhaust gas purification catalyst of an internal combustion engine, in particular a motor vehicle required. The invention therefore also relates to a reductant supply system with the in the preamble of claim 26 given characteristics.

Particularly in motor vehicles, liquid-conducting systems, for example reducing agent supply systems, can freeze in frost, so that the fluid lines of such systems must be heated. Possibilities for heating the liquid lines of a reducing agent supply system, for example, from DE 10 2005 029 290 A1 known.

With Reducing agents become nitrogen oxides in the exhaust gas purifying catalyst reduced to nitrogen. As a reducing agent in the true sense is ammonia used by default, which consists of urea is won. For the purposes of the application is therefore under a reducing agent also its precursor, such as urea, understood, from the actual reducing agent in the chemical sense, for example Ammonia, is recovered.

at Frost can freeze urea solution from an exhaust gas purifying catalyst as an ammonia supplier is needed. For this reason will be for reducing agent supply systems electrically heated Feed lines used, so even in heavy frost urea solution is pumped rapidly to the catalyst can.

task The invention is to show a way, as in a reducing agent supply system with heated liquid lines in frost faster Operational readiness can be achieved.

These Task is by a connector with the in the claim 1 specified characteristics solved. Advantageous developments The invention is the subject of the dependent claims.

One Liquid line system with heated liquid lines can be put into operational readiness faster in frost, by connecting the fluid lines with a heated connector to other system components such as pumps or exhaust valves, be connected. In an inventive Connecting piece extends an electrically heated Heating rod in the fluid channel, leaving liquid heated in the fitting particularly quickly and efficiently can be. In particular, the heating element of an inventive Connection piece into a plug or similar Connecting part of another component of a fluid line system, For example, a pump, extend into it and there Heating the liquid cause.

One inventive connector can in terms of its two openings, passing through the fluid channel connected to standard sizes for Plug connections formed by liquid lines and therefore easy to connect a heated liquid line be used on a pump or a similar component. Because of inventively provided heatable Heating rod in the fluid channel of an inventive Connector can also be used when connecting to a non-heated Component of a commercially available connector fluid be heated efficiently. In particular, also for the Connection of the heating element can be used a standard connection.

One inventive connector is in particular suitable for this purpose, an electrically heatable fluid line to a non-heated part of a connector another Component of a fluid conduit system, for example a pump to connect. It is particularly favorable when the heater is only in a first section of the fluid channel extends. When connecting a non-heated connection part of a plug connection At the first opening, the heating rod can even be connected to the Protruding connector and also there liquid efficient heat. A second section emanating from the second opening the liquid channel preferably has an electrically heatable Channel wall carrying a resistance heating element. Prefers the first section is angled, more preferably at an angle of 45 ° to 135 °, in particular at an angle of 90 °, to the second section.

Preferably, the heating element has an inner conductor and a tubular outer conductor surrounding the inner conductor. This measure has the advantage of easy installation, since such a heating element can be inserted without risk of damage in a plastic housing of the connector. It is particularly preferred that the outer conductor the Heating element forms, as this allows a very thin heating element. Preferably, the outer conductor has an outer diameter of 1 to 5 mm, in particular 1.5 to 3 mm. The outer conductor of the heating element is preferably made of stainless steel and has a wall thickness of 0.1 to 0.3 mm.

Of the Heating rod is preferably in a metal sleeve, over the outer conductor is electrically contacted. To this Way can be set easily and reliably, like long the section of the outer conductor used as heating resistor is because the heating current through the outer conductor then from the metal sleeve up to the end projecting into the liquid channel of the heating element flows. If the outer conductor is liquid-tight connected to the metal sleeve, for example, welded, can also be the sealing of the opening of the fitting, through which the heating element is inserted, made easier. The metal sleeve can namely with an outer diameter be selected, the standard sealing elements, for example O-rings, which are also used to seal male connectors used, fits.

Further Details and advantages of the invention will become apparent from embodiments explained with reference to the accompanying drawings. The same and corresponding components are with matching Reference numbers marked. The features explained below may individually and in combination to the subject of claims be made. Show it:

1 An embodiment of a connector according to the invention for a liquid line;

2 Another embodiment of a connector;

3 the current path of the embodiment shown in FIG.

4 the heating element of the 2 illustrated embodiment in a longitudinal section;

5 Contact rings of in 2 illustrated embodiment for the electrical connection of a male connection part; and

6 a schematic representation of an embodiment of a reducing agent supply system for an exhaust gas purification catalyst of a motor vehicle.

1 shows a connection piece in a sectional view 1 for a fluid line, which has a first opening 2 and a second opening 3 that passes through a fluid channel 4 are connected. The first opening 2 is here as a female part of a connector for receiving a male part 5 a plug connection formed and in 1 with an inserted male part 5 a connector shown with which it is locked. The second opening 3 is at the in 1 illustrated embodiment also formed as a female part of a connector and with an inserted male part 10 shown.

The fluid channel 4 in the fitting 1 has one from the first opening 2 outgoing first section, in which the heating element 6 extends, and one from the second opening 3 outgoing second section which extends transversely to the first section, in particular at an angle of 90 °. The second section of the fluid channel 4 is in the illustrated embodiment, only on the inserted plug 10 heated, having a heating device. It is also possible to equip the second section of the liquid channel with an electrically heatable channel wall, which carries an unillustrated resistance heating element. Such a resistance heating element can be, for example, a heating wire, which is in the surrounding the first portion plastic housing of the connector 1 is embedded.

The heating rod 6 protrudes from a sealed housing opening of the connector 1 out. In the illustrated embodiment, the seal with an O-ring surrounding the heating element 9 reached.

2 shows a further embodiment of a connector 1 in which not only both of the fluid channel 4 connected openings 2 . 3 are formed as a female part of a connector for receiving a male part of a connector, but in addition also the insertion opening for the heating element 6 ,

When in the first opening 2 introduced male connector 5 it is a commercial plug into which the heating element extends. When in the second opening 3 inserted connection part 10 it is a heated plug of a heated liquid line 11 , The heated plug 10 has on its outside a metal sleeve 12 that has a contact ring 13 trained contact point of the connector 1 is contacted electrically. The contact ring 13 is in the connector 1 to a connecting cable 24 connected, with the heating current during operation to a heating of the inserted plug 10 and a connected liquid line 11 is directed. These in the fitting 1 extending connection line 24 can as Wi derstandsheizelement be formed to cause additional heating of the connector, which is advantageous for example when connected to liquid lines that are not heated to the end.

The heating rod 6 is about the contact point 23 and the connection line 24 with the contact point 13 connected in series, allowing the heating of a connected fluid line 11 and the heating rod 6 of the connector 1 via an electrical connection of the connection piece 1 can be supplied with voltage. That from the case 15 outstanding end of the inner conductor of the heating element 6 forms this electrical connection. But it is also possible, the heating element 6 separately heatable form and, for example, parallel to the heating of a connected liquid line 11 to switch.

The heating rod 6 of in 2 illustrated embodiment is of a connector 41 worn in a fitting fitting of the fitting 1 plugged. For this is the heating element 6 in a metal sleeve 14 , the same outer diameter as the metal sleeve 12 one in the second opening 3 matching male connector 10 Has. In this way, the plastic housing 15 of the connector 1 can be inexpensively manufactured as a T-piece whose three housing openings have matching dimensions. In particular, the same seals can be used for sealing. In the illustrated embodiment, the inserted male terminal parts 5 . 10 as well as the metal sleeve 14 in which the heating element 6 stuck, of O-rings 16 surround. The metal sleeve 14 in which the heating element 6 is also from a contact ring 23 enclosed in the plastic housing 15 injected connection cable 24 with the contact ring 13 the second housing opening 3 connected is. The electrical connection is made behind the O-ring 16 , d. h on whose the opening of the connector 1 facing side, and is therefore protected from liquid.

The current path through which a heating current in operation via the heating element 6 , the metal sleeve 14 , the connection cable 24 , the metal sleeve 12 of the connected connection part 10 and the liquid conduit formed as a metal pipe 11 flows, is in 3 shown. The metal sleeves 14 and 12 have the same outer diameter and are each formed by identically formed contact rings 13 . 23 electrically contacted. The connection piece 1 and the matching connector 10 Form in this way a connector that both an electrical connection and a hydraulic connection, ie the connection of a liquid line 11 causes.

4 shows the heating element 6 of in 2 illustrated embodiment in a longitudinal section. The heating rod 6 has an inner conductor 17 and a tubular outer conductor 18 , the inner conductor 17 surrounds and is connected in series with it. The outer conductor 18 has a greater electrical resistance than the inner conductor 17 , In particular, an at least ten times as large electrical resistance, so that by a heating current predominantly, in particular almost exclusively, the outer conductor 18 is heated, which can quickly transfer its heat to surrounding liquid. The inner conductor 17 is preferably made of copper, the outer conductor 18 made of stainless steel, for example V4A steel. Between inner conductor 17 and outer conductor 18 there is an isolator 19 , At its end carries the heating rod 6 a metal cap 20 that with the outer conductor 18 liquid-tight connected, for example, welded, and electrically conductive to the inner conductor 17 , for example by crimping, is connected.

As already mentioned, the heating element is plugged 6 in a metal sleeve 14 with which he liquid-tight connected, for example, welded, so that both an electrical contact and a liquid-tight connection is given. The from the metal sleeve 14 outstanding section of the outer conductor 18 forms the heating element. The metal sleeve 14 Because of its size has a much smaller electrical resistance than the outer conductor 18 , In this way he will reach out to the heating element 6 only with his from the metal sleeve 14 in the first section of the fluid channel 4 projecting end is heated. In this way, that of the heating element 6 released thermal heat can be used very efficiently and the risk of overheating of the plastic housing 15 of the connector 1 be countered.

In 5 are the contact rings 13 . 23 for electrically contacting the metal sleeve 14 in which the heating element 6 as well as one into the second opening 3 inserted plug 10 in detail with the connecting cable connecting them 24 in the plastic case 15 of the connector 1 is embedded. The contact rings 13 . 23 have spring bows 21 on, when inserting the metal sleeve 14 or a male connector 10 yield resiliently and establish an electrical contact. The spring bows 21 are through lenticular breakthroughs 22 the contact rings 13 . 23 educated. The spring bows 21 can resiliently yield radially outward and cause in this way an electrical contact with an inserted metal sleeve.

The contact rings 13 . 23 additionally serve as a stop for the positioning of in 2 illustrated O-rings 16 , Embedding the two contact rings 13 . 23 connecting connecting cable 24 in the plastic housing 15 of the connector 1 The easiest way to do this is to check that the plastic housing 15 as an injection molded part around the connecting cable 24 is sprayed around.

6 schematically shows a reducing agent supply system 30 of a motor vehicle connected to an exhaust gas purification catalyst 31 connected. In the exhaust purification catalyst 31 Nitrogen oxides are reduced to nitrogen by means of ammonia. The ammonia required for this purpose is obtained from urea solution supplied by the reducing agent supply system 30 is provided, and the exhaust stream 32 via a metering valve 33 in the catalyst 31 is added.

Of the Term emission control catalyst is here according to the in the vehicle technology common usage for used a device for exhaust gas purification, which is a catalyst contains in the chemical sense. Furthermore, the term reducing agent is also used for Used urea solution, from which the reducing agent is won in the true sense.

This in 6 shown reducing agent supply system 30 includes a reducing agent tank 34 for absorption of urea solution 39 , an electrically heated liquid line 36 to reducing agent from the reducing agent tank 34 to the exhaust gas purifying catalyst 31 to transport, and a pump 37 to reductant through the fluid lines 35 . 36 from an outlet opening 38 of the reducing agent tank 34 to pump to the catalyst. The heatable fluid line 36 is about a connector 1 as stated above with reference to 2 described to the pump 37 connected. Likewise, the liquid line 36 with such a connector 1 also to the dosing valve 33 be connected.

The pump 37 and the catalyst 31 be from a control unit 40 controlled, the frost in an electrical heating of the reducing agent tank 34 , the pump 37 , the connector 1 and the fluid lines 35 . 36 turns. The pump is preferred 37 to the tank 34 arranged adjacent, so that the line section 35 can be so short that it can be heated sufficiently by the tank or / and pump heating and therefore on its own heating of the short line section 35 can be waived.

The fluid line 35 . 36 is formed by corrosion-resistant metal pipes, preferably made of stainless steel, for example of V4A steel. For isolation, these are surrounded by a corrugated plastic jacket. For heating is between the ends of the liquid line 35 . 36 a voltage is applied so that a current flows through the metal tubes of the fluid line 35 . 36 heated.

1

connector

2

First opening

3

Second opening

4

liquid channel

5

male connector

6

heater

7

channel wall

8th

resistance

9

O-ring

10

male connector

11

liquid line

12

metal sleeve

13

contact ring

14

metal sleeve

15

casing

16

O-ring

17

inner conductor of the heating element

18

outer conductor of the heating element

19

insulator

20

metal cap

21

spring bows

22

breakthrough

23

contact ring

24

connecting cable

30

Reducing agent supply system

31

purifying catalyst

32

exhaust gas flow

33

metering valve

34

Reductant tank

35

liquid line

36

liquid line

37

pump

38

outlet of the urea tank

39

urea solution

40

control unit

41

Connectors

A

current path

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102005029290 A1 [0003]

Claims (26)

Connecting piece for a fluid line ( 11 . 35 ), which has a first opening ( 2 ) and a second opening ( 3 ), which pass through a fluid channel ( 4 ), characterized by an electrically heatable heating rod ( 6 ) located in the fluid channel ( 4 ). Connecting piece according to claim 1, characterized in that the heating element ( 6 ) an inner conductor ( 17 ) and a tubular outer conductor ( 18 ), the inner conductor ( 17 ) surrounds. Connecting piece according to claim 2, characterized in that the outer conductor ( 18 ) forms the heating element. Connecting piece according to one of the preceding claims, characterized in that the connecting piece ( 1 ) a connection line ( 24 ) with an electrical contact point ( 13 ) to supply a heating current to a heater to the second opening ( 3 ) connected fluid line ( 11 . 35 ). Connecting piece according to claim 4, characterized in that the heating element ( 6 ) with the contact point ( 13 ) is connected in series. Connecting piece according to claim 4 or 5, characterized in that the connecting line ( 24 ) contains a resistance heating element. Connecting piece according to one of claims 4 to 6, characterized in that the connecting piece ( 1 ) has an electrical connection, via which the heating element ( 6 ) and to a heater one to the second ( 3 ) Opening connected fluid line ( 11 ) A supply voltage can be applied. Connecting piece according to one of the preceding claims, characterized in that the heating element ( 6 ) in a metal sleeve ( 14 ) plugged. Connecting piece according to claim 8, characterized in that the outer conductor ( 18 ) with the metal sleeve ( 14 ) connected liquid-tight, preferably welded, is. Connecting piece according to claim 8 or 9, characterized in that the outer conductor ( 18 ) over the metal sleeve ( 14 ) is electrically contacted. Connecting piece according to claim 10, characterized in that the metal sleeve ( 14 ) via a contact point, preferably a contact ring ( 23 ), is electrically contacted. Connecting piece according to one of claims 2 to 11, characterized in that the outer conductor ( 18 ) is a stainless steel tube. Connecting piece according to one of the preceding claims, characterized in that the fluid channel ( 4 ) in the fitting ( 1 ) one from the first opening ( 2 ) outgoing first section, in which the heating element ( 6 ) and one of the second opening ( 3 ) outgoing second section. Connecting piece according to claim 13, characterized that the first section angled, preferably at an angle from 45 ° to 135 °, in particular at an angle from 90 °, to the second section. Connecting piece according to one of the preceding claims, characterized in that the heating element ( 6 ) from a sealed housing opening of the connector ( 1 ) stands out. Connecting piece according to one of the preceding claims, characterized in that the first opening ( 2 ) as a female part of a connector for receiving a male part ( 5 ) is formed a plug connection. Connecting piece according to claim 16, characterized in that the heating element ( 6 ) so far in the fluid channel ( 4 ) extends into a first opening ( 2 ) male connector ( 5 ) protrudes. Connecting piece according to one of the preceding claims, characterized in that the second opening ( 3 ) as a female part of a connector for receiving a male part ( 10 ) is formed a plug connection. Connecting piece according to claim 18, characterized in that the connecting piece ( 1 ) a plastic housing ( 15 ) comprising a metallic contact piece, preferably a metallic contact ring ( 13 ), the one in the second opening ( 3 ) plugged connection part ( 10 ) contacted electrically. Connecting piece according to claim 19, characterized in that the contact ring ( 13 ) with the contact ring ( 23 ), which is the heating element ( 6 ) surrounding sleeve ( 14 ), through the connecting line ( 24 ) connected is. Connecting piece according to claim 19 or 20, characterized in that the contact ring ( 13 ) Spring bows ( 21 ), which when inserting a male connector ( 5 . 10 ) into the second opening ( 3 ) yield and the connecting part ( 10 ) to contact. Connecting piece according to one of claim 20 or 21, characterized in that in operation a heating current via an inserted into the second opening connecting part ( 10 ), the connecting cable ( 24 ), the metal sleeve ( 14 ), the outer conductor ( 18 ) and the inner conductor ( 17 ) he follows. Connecting piece according to one of the preceding claims, characterized in that the heating element ( 6 ) from a connector ( 41 ) carried in a receptacle of the fitting ( 1 ) plugged. Connecting piece according to claim 23, characterized in that by inserting the connector ( 41 ) an electrical contact is closed, over which the heating element ( 6 ) is supplied with power during operation. Plug connection with a connection piece ( 1 ) according to one of the preceding claims and a matching connection part ( 10 ), whereby the connection piece ( 1 ) and the connection part ( 10 ) are formed such that when connecting the connector ( 1 ) with the connection part ( 10 ) an electrical contact is closed. Reducing agent supply system for an exhaust gas purifying catalyst ( 31 ) of an internal combustion engine, in particular of a motor vehicle, with a reducing agent tank ( 34 ) for receiving reducing agent, an electrically heatable liquid line ( 35 . 36 ) to remove reducing agent from the reducing agent tank ( 34 ) to an exhaust gas purifying catalyst ( 31 ) and a pump ( 37 ) to reductant through the fluid lines ( 35 . 36 ) from the reducing agent tank ( 34 ) to the catalyst ( 31 ), characterized in that the liquid line ( 35 . 36 ) to a connector ( 1 ) is connected according to one of the preceding claims.