DE29711720U1 - Valve arrangement - Google Patents

Description

R.31696

ROBERT BOSCH GMBH, 70442 Stuttgart

Valve arrangement

The invention relates to a valve arrangement, in particular for an exhaust gas recirculation valve for internal combustion engines.

State of the art

It is known to use exhaust gas recirculation valves in internal combustion engines. These are used to mix exhaust gases from the internal combustion engine with the intake air of an internal combustion engine in order to reduce the oxygen content of the intake air. By reducing the oxygen content in the intake air, the formation of nitrogen oxide can be minimized during the combustion process taking place in the internal combustion engine.

Known exhaust gas recirculation valves have two independently operable valve devices, of which a first regulates the total air flow of the valve arrangement and a second regulates an exhaust gas admixture. The valve devices are operated via actuating devices that can be subjected to negative pressure, so-called pneumatic

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pressure cans. For this purpose, the actuating devices are connected to a vacuum source. The actuating devices are controlled by switching means, which are formed by solenoid valves, for example. The solenoid valves are used to adjust the application of the vacuum to the actuating device.

In known valve arrangements, both the actuating devices and the switching means are arranged in a common housing. Each of the actuating means is connected to the vacuum source via an associated connection and each of the switching means is connected to a voltage source via an associated connection. The disadvantage here is that a large number of connections must be made to ensure the function of the valve arrangement. In addition to the associated assembly effort, there are a large number of sealing points that need to be sealed.

Advantages of the invention

The valve arrangement according to the invention with the features mentioned in claim 1 offers the advantage that assembly, connection and sealing costs are reduced to a minimum. Because a housing cover simultaneously has connection paths for an electrical contact of the switching means and a pneumatic contact of the actuating means, which can each be connected to the supply sources via a connection, only

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another connection for pneumatic contact and one connection for electrical contact are necessary. The internal distributions are handled by connecting paths integrated into the housing cover. In particular, if the housing cover is preferably designed as a plastic injection-molded part, the connecting paths can be integrated during the manufacture of the housing cover, so that additional joints that would require additional sealing effort are not present. When assembling the valve arrangement, only one connection for pneumatic contact and one connection for electrical contact are required. The number of connecting lines leading to the valve arrangement is thus also reduced.

Further advantageous embodiments of the invention result from the remaining features mentioned in the subclaims.
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drawings

The invention is explained in more detail below in an embodiment using the accompanying drawings. They show:

Figure 1 a perspective view of a housing cover
;

0 Figure 2 a top view of the housing cover

according to Figure 1 and

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Figure 3 is a side view of the housing cover according to Figure 1.

Description of the implementation example
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Figure 1 shows a perspective view of a housing cover 10 of an exhaust gas recirculation valve (not shown in detail). The housing cover 10 has a first cover section 12 and a second cover section 14. The cover sections 12 and 14 are pot-shaped and can be placed on actuating devices of a valve arrangement formed by pneumatic vacuum cans. The structure and mode of operation of the actuating devices will not be discussed further in the context of this description, as these are generally known.

The cover sections 12 and 14 are overlapped by a connection module 16, which on the one hand comprises a pneumatic connection 18 and an electrical connection 20. The pneumatic connection 18 is formed by a tubular element 22, which has a connection 24 for connection to a vacuum source (not shown). The element 22 has integrated connection points 26 (Figure 3) at which the pneumatic vacuum boxes are connected to the pneumatic connection 18. For this purpose, connection pieces 28 are provided, which are formed in one piece with the tubular element 22 and open into the cover sections 12 and 14.

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The connecting pieces 28 simultaneously accommodate a closing body (not shown) of a switching means designed as a solenoid valve 34 (Figure 2) for the actuating devices. A connection between the tubular element 22 and the cover sections 12 or 14 can be closed or opened by means of the closing body. The solenoid valves 34 have electrical connection contacts 36 which are contacted with electrical lines 38 integrated in the connection module 16. In the example shown, a total of three electrical lines 38 are provided by means of which the two solenoid valves 34 can be controlled. One electrical line 38 is provided for supplying the solenoid valves with a control signal, while the third electrical line 38 is designed as a common ground line for the solenoid valves 34. The electrical lines 38 are led out of the connection module 16 on a contact plug 40.

The electrical lines 3 8 are formed, for example, by contact plates 42, which are integrated into the connection module 16 as prefabricated electrical connections during injection molding of the connection module 16 in accordance with the connection diagram. Additional expenditure for electrical insulation and/or sealing is therefore not necessary. The electrical lines 3 8 are only led out of the connection module 16 at the contact points in the contact plug 4 0 and to the connection contacts 36 of the solenoid valves 34.

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The housing cover 10 with its connection module 16 makes it possible to connect both actuating devices of the valve arrangement together with a vacuum source and a voltage source, whereby only one connection point for the vacuum (connection 24) and one connection point for the electrical contact (contact plug 40) are required. In valve arrangements with several actuating devices and/or switching means, the housing cover 10 can of course be extended accordingly, so that regardless of the number of actuating devices and/or switching means, only one connection for the vacuum source and one connection for the voltage source is required.

The housing cover 10 also has connecting pieces 48 to which a reference air source (atmosphere) for the actuating devices can be connected. As can be seen from Figures 1 and 3, the housing cover 10 can be connected to the housing of the exhaust gas recirculation valve via locking means 44 for mechanical stabilization. For this purpose, locking windows 46 are provided into which corresponding locking lugs on the housing can be locked.

Overall, this results in a detachable connection between the housing cover 10 with integrated connection module 16 and the housing. By simply snapping on the housing cover 10, the valve arrangement can be completed in a simple manner. Overall, this means that the valve assembly can be mass-produced cost-effectively using a simple plastic injection-molded part.

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Electrical and pneumatic contacting of the valve arrangement is possible at the same time thanks to the connection modules 16. Due to the compact design and the housing cover 10 consisting of only one part with integrated connection module 16, complex sealing measures are not required.

Claims (8)

R. 31696 Protection claims 1. Valve arrangement, in particular exhaust gas recirculation valve for internal combustion engines, with at least two valve devices, which can be actuated independently of one another via an actuating device which can be subjected to negative pressure, and switching means assigned to the actuating devices and arranged with them in a common housing, characterized in that a housing cover (10) simultaneously has connection paths for electrical contacting of the switching means (34) and pneumatic contacting of the actuating devices, which can be connected to the corresponding supply sources via a respective connection (24, 40). 2. Valve arrangement according to claim 1, characterized in that a connection module (16) is integrated in the housing cover (10), which forms both electrical and pneumatic connections (18, 20). 3. Valve arrangement according to one of the preceding claims, characterized in that the pneumatic connection (18) can be connected to a vacuum source via a connection (24), and connection 2 R. 31696 connection parts (26) for connecting the actuating devices. 4. Valve arrangement according to one of the preceding claims, characterized in that the connection points (26) are formed by connecting pieces (28) into which the switching means (34) are integrated. 5. Valve arrangement according to one of the preceding claims, characterized in that the electrical connection (20) is formed by electrical lines (3 8) integrated in the connection module (16). 6. Valve arrangement according to one of the preceding claims, characterized in that the electrical lines (38) are integrated into the connection module (16) by positioning contact plates (42) during the manufacture of the connection module (16) during injection molding. 7. Valve arrangement according to one of the preceding claims, characterized in that the connection module (16) is a plastic injection-molded part. 8. Valve arrangement according to one of the preceding claims, characterized in that the housing cover (10) can be detachably connected to the valve arrangement via at least one locking means (44).