WO2008129001A1

WO2008129001A1 - Connecting element for fluid lines and component conducting a pressure fluid

Info

Publication number: WO2008129001A1
Application number: PCT/EP2008/054747
Authority: WO
Inventors: Günter LEWENTZ
Original assignee: Continental Automotive Gmbh
Priority date: 2007-04-24
Filing date: 2008-04-18
Publication date: 2008-10-30
Also published as: DE102007019332A1

Abstract

The invention relates to a connecting element (10) for fluid lines, particularly to a connecting branch for pressure fluid connections of hydraulic pumps, comprising a rigid line section, which has a stop collar (20) at an outer lateral surface, a centering collar (22) connecting to the stop collar, a sealing element and means for mechanical locking. A component conducting a pressure fluid comprises at least one connecting region for receiving and/or locking such a connecting element (10).

Description

description

Connection element for fluid lines and pressure fluid leading component

The present invention relates to a connection element for fluid lines. The invention further relates to a pressure fluid leading component having at least one connection area for receiving and / or locking of such a connection element. In addition, the invention relates to a hydraulic pump with such a device.

In a fuel supply system for internal combustion engines, storage injection systems are frequently used which operate with very high injection pressures at the fuel injection nozzles and thus with overall high system pressure. In a storage injection system, fuel is conveyed by means of a high-pressure pump to fuel injectors, with the aid of which the fuel is injected into the combustion chamber of the internal combustion engine. Such a fuel injector has an injection valve which is hydraulically opened or closed by a control valve with the aid of the fuel pressure applied to the fuel injector. The control valve is actuated by an electrically actuated actuator. The accumulator injection system further comprises a high-pressure accumulator, a so-called storage line or common rail, which is arranged between the high-pressure pump and the fuel injectors and which ensures that the fuel injectors are provided with a constantly high system pressure.

Fuel pumped from the tank of the vehicle, which could not be injected and burned due to the current fuel demand, must be returned from the high pressure pump to the tank via a return line. For both the inlet and the return line corresponding connections must be provided on the pump. Due to the different installation and connection conditions at different locations or in different types of vehicles, it is necessary to dimension these connections differently depending on the needs and / or to be able to. In this way, the connections can be individually adapted to the particular periphery of the fuel system. So that in this context as little or no changes to the layout of the pump housing must be made, it makes sense to make the connection areas for the lines in all pumps largely identical. Other requirements of the line connections relate to their media resistance, temperature resistance and mechanical robustness against all occurring bending, impact and vibration influences.

DE 199 40 387 C1 discloses a leakage connection for attaching a leakage line to a fuel injector. The leakage connection has a connection piece, which is formed integrally with the injector body, and a connection nipple, which engages with an insert in an opening in the connection piece. A flexurally elastic securing device is held with a first arm in a recess on the connecting piece. With a second arm, a clamping connection with the connecting piece is produced in an end position.

The invention is based on the object to provide a connection element for fluid lines available, which is as compact and simple as possible, and which allows a solid and media-tight connection to a pressure fluid-carrying device.

This object is achieved by the features of claim 1. Advantageous developments, Ausgestaltun- conditions and variants of the invention are the subject of the dependent claims. In a connecting element according to the invention for fluid lines, which may be provided in particular for use in fuel supply system of internal combustion engines, a rigid pipe section is provided which has on an outer circumferential surface a connection collar, an adjoining centering collar, a sealing element and means for mechanical locking. The connection element can be designed, in particular, as a connecting piece for pressure fluid connections of hydraulic pumps. In this connection it can be provided that the line section optionally has round and / or oval cross-sections of different diameters.

Such a connection element has the advantage that in a simple manner a pluggable and / or latchable connection with a housing, a receptacle o. The like. will be produced. The connection element is particularly suitable for use with fuel lines. Elaborate screwing, pressing or gluing can be dispensed with altogether.

The connecting element can be made of a different material than the receptacle into which it is introduced. Preferably, the connection element or the connection nipple is made of plastic, in particular as a plastic injection-molded part. Due to the connection, there are no problems due to different thermal expansion behavior of different materials, as might be the case for example with press connections. Due to the omission of an adhesive connection, it is only necessary to pay attention to the fuel and media resistance of the connection element. On the media resistance of an adhesive connection no consideration needs to be taken, as a bond is not necessary.

With regard to the component dimensions, relatively large tolerances are permissible since the connection technology does not require a high-precision fit. The force for producing the latching connection Training is not very high, so that no plastic deformations of possibly made of plastic connection element are to be feared.

The means for mechanical locking can be formed for example by a spring ring, which is held in an annular groove on the outer circumferential surface of the line section. Preferably, the spring ring corresponds with a groove on an inner circumferential surface of a receptacle of a line counterpart. The spring ring may have a round, an oval or a polygonal cross section. This locking connection by means of an elastically deformable spring ring is very simple and inexpensive to manufacture and can be easily assembled and dismantled if necessary.

According to an alternative embodiment, the means for mechanical locking may be formed by at least one latching hook arranged on the outer circumferential surface of the line section. In this case, two, three or more locking hooks may be provided, which on the outer circumferential surface of the

Line section are arranged distributed. Such locking hooks may be provided instead of a spring ring or in addition to such. A stable and always removable locking connection is also created with this variant.

In an advantageous embodiment, the sealing element is formed by at least one O-ring, which is arranged and / or held on the outer circumferential surface of the line section. The O-ring is preferably held in an annular groove. Such an O-ring is very inexpensive and can reliably fulfill the desired sealing task.

Furthermore, it can be provided that the connection element has an angled connection section. The connection element may also optionally have a branch and two or more nozzle sections. Depending on requirements, the desired line sections and connection elements are made available for a variety of purposes.

The invention further comprises a hydraulic and / or pneumatic medium or pressure fluid leading component having at least one connection area for receiving and / or locking a connection element according to one of the embodiments described above. An embodiment variant provides a component in which the connection region has at least one centering section with means for interacting with the means for mechanical locking and at least one sealing section of smaller inner diameter than the centering section for cooperation with the sealing element. It can also be provided that the centering and / or the sealing portion are each formed in a hollow cylindrical or conical shape.

Expediently, a hollow cone-shaped connecting section is provided between the sealing section and the centering section. At the bottom of the connection area is usefully a

Pipe connection provided, which is at least partially aligned with the line section.

Such a component represents a cost-effective and simple possibility for the creation of line connections, so that in many different applications, costly solutions can often be dispensed with and standard connections can be resorted to.

Further aspects and advantages of the component according to the invention emerge from the previously described embodiments of the connection element.

Particularly advantageously, the connection element is latched and / or glued in the connection region of the component. This arrangement may in particular be part of a hydraulic pump. The advantages achieved by the invention are, in particular, that a connection nipple, which is generally referred to as a connection element, can be designed as a plastic injection-molded part. The design of the nipple can or should have geometry details, according to which an axial mounting stop is provided, which can be realized by a corresponding collar diameter. A radial centering can be achieved by matching the diameter of the nipple with the diameter of the bore in the counterpart. The sealing to the outside to prevent leakage (eg of fuel) and inward to prevent the ingress of external media (eg spray water) can be achieved by means of a proven O-ring. The holding function can be taken over in particular by an open spring ring, which holds the nipple in a form-fitting manner in the receiving bore in combination with a background rotation (groove) in the bore. The spring ring can in particular be made of a spring wire with a round or square cross-section. In an alternative embodiment, the nipple can also be provided with molded barbs or latching hooks, which then snap umbrella-shaped into the groove and secure the nipple against withdrawal.

The nipple does not necessarily have to be disassembled again after it has been mounted, since, for example, the supply and return lines are mounted or dismounted on the nipple in the case of a pump. The nipple itself is not preassembled in the prefabricated leakage line and is therefore not part of the leakage line. Depending on requirements, however, the nipple can also be assigned to the corresponding hose line, so that it is inserted into the pump only when it is mounted on the motor. In order to avoid confusion between the inlet and the return line when installing the connection element, the two nipples can be provided with different diameters. In this way, each connection element only fits into the receptacle provided for this purpose, but not into the respective other receptacle. By means of the solution according to the invention, the various functions to be performed are assigned to different components which are most suitable for this purpose. The sealing task is fulfilled by the O-ring, while the axial protection is achieved by the spring ring. The design as a plastic injection molded part provides a very cost-effective component. The assembly is very simple, which is supported by positive snap connections. The pressing forces and paths do not need to be monitored separately. Damage due to incorrect handling and assembly is almost impossible. Different requirements can be easily taken into account, since the upper part of the nipple can be designed freely. By appropriate variation of the upper part of the nipple can be easily converted to specific hose connections, the lower part of the nipple can remain unchanged.

The connection area, which is provided for connection to a hose line, can be designed differently and / or bent or angled. If necessary, two or multiple outlets can be provided, which can be configured as branches. The Innenbzw. Counter contour can be produced by means of a suitable mold in a simple and cost-effective manner.

Are the loads to which the nipple is exposed, comparatively large, this can optionally be made of steel, brass or other suitable material.

Embodiments of the invention will be explained in more detail with reference to a drawing. Show:

1 shows a first variant of a connection element in a schematic longitudinal section,

2 a serving as a fuse element spring ring in different views, 3 shows a second variant of the connecting element in a schematic longitudinal section,

4 shows a further view of the first variant of the connection element according to FIG. 1,

5 shows a third variant of the connecting element in a schematic representation,

6 shows a fourth variant of the connecting element in a schematic representation,

7 shows a fifth variant of the connecting element in a schematic representation,

8 shows a sixth variant of the connecting element in a schematic representation, and

9 shows possible installation variants for connection elements using the example of a fuel pump.

The same parts are provided in all figures with the same reference numerals.

The schematic representation of FIG 1 shows a first variant of a connecting element 10 for fluid lines (not shown) in a schematic longitudinal sectional view. The connection element 10 is located in a suitable bore 12 of a housing 14 which, for example, is a pump housing, cover or the like. can be. The bore 12, which in this context is also referred to as a connection region of a component carrying pressure fluid, has graduated diameters which, in conjunction with the connection element 10 -also also referred to as connection nipple 16 or as inlet or return nipple-each have different functions fulfill. Thus, the connecting element 10 or the connecting nipple 16 essentially comprises six components, namely a central fluid bore 18, a stop collar 20 for defining the immersion depth of the nipple 16 in the housing 14, an upper centering section 22 of smaller diameter than the stop collar 20, one on it adjoining conical section 24, a sealing section 26 of smaller diameter than the centering section 22, and an upper connecting section 28 for connection to a hose line, for example a fuel or hydraulic line, which protrudes out of the housing 14 out of the stop collar 20.

In the cylindrical upper centering portion 22, an annular groove 30 is incorporated, which receives a spring ring 32. This provides in cooperation with a corresponding annular groove 34 in the inner circumferential surface of the bore 12 for the mechanical securing of the connecting element 10 in the axial direction. In the cylindrical lower sealing portion 26, a further annular groove 36 is provided, which serves to receive an acting as a sealing element O-ring 38. This ensures a liquid-tight seal of the sealing portion 26 of the connecting element 10 against the bore 12th

The schematic representation of FIG. 2 shows a spring ring 32 according to FIG. 1 serving as a securing element in various views. It can be seen from the top illustration that the spring ring 32 has an opening, so that it can deform elastically and be introduced into the corresponding annular groove 30 on the centering section 22 of the connection element 10. The two lower views show different ring cross-sections of the spring ring 32, which may optionally have a round, a square or otherwise shaped cross-section.

The representation of FIG. 3 shows a second variant of the connection element 10 in a schematic longitudinal section. This second variant of the connecting element 10 has instead of a spring ring for axial fixing in the bore 12 of the Housing 14 two or more locking hooks 40, which can engage in a matching annular groove 34 on the inner circumferential surface of the bore 12 and thus form a releasable latching connection. For this purpose, molded in the plastic component latching hooks 40 are shaped so that they can dodge elastically inwards. Between the centering section 22 below the stop collar 20 and the sealing section 26 with the O-ring 38 arranged therein, a conical transition section can also be provided in this variant, which, however, can not be seen in the illustrated sectional plane of FIG. The remaining structure of the connecting element 10 according to FIG. 3 corresponds to that of the first variant according to FIG.

FIG. 4 shows a further view of the first variant of the connection element 10 according to FIG. 1, which has a straight connection section 28.

5 shows a third variant of the connecting element 10 in a schematic representation. Here, the nozzle portion 28 is angled or cranked by 90 degrees.

In contrast, the schematic representation of FIG 6 shows a fourth variant of the connecting element 10, in which the nozzle portion 28 is angled at an angle α of about 45 °.

7 shows a fifth variant of the connecting element 10, which has a branching point 42 and, subsequently, two connecting piece sections 28, which are each offset by about 45 °.

The schematic representation of FIG. 8 shows a sixth variant of the connection element 10 and illustrates the possibility of choosing the connection section 28 in different design variants such that it can satisfy different requirements. The lower portion of the connecting element 10 below the stop collar 20, however, is component-specific and thus hardly variable. 9 shows possible installation variants for such connection elements 10 using the example of a housing 14 of a fuel pump 44. The reference numeral 46 designates a nozzle for the fuel inlet, while the reference numeral 48 denotes a nozzle for the fuel return. This illustration clarifies that the connection region of the connection elements 10 can each be designed the same, while the connection section 28 can be formed differently if necessary.

The invention is not limited to the above embodiments. Rather, a multiplicity of variants and modifications are conceivable which make use of the inventive concept and therefore also fall within the scope of protection.

Claims

claims

1. connection element (10) for fluid lines, in particular connecting piece for pressure fluid connections of hydraulic pumps, with a rigid pipe section (18) on an outer circumferential surface a stop collar (20), an adjoining centering collar (22), a sealing element (36, 38) and means (32, 40) for mechanical locking.

2. Connecting element according to claim 1, wherein the line section (18) each have round and / or oval cross-sections of different diameters.

3. Connection element according to claim 1 or 2, wherein the means for mechanical locking by a spring ring (32) are formed, which is held in an annular groove (30) on the outer circumferential surface of the line section.

4. Connection element according to claim 3, wherein the spring ring

(32) with an annular groove (34) on an inner circumferential surface of a receptacle of a line counterpart corresponds.

5. Connecting element according to one of claims 3 or 4, wherein the spring ring (32) has a round, an oval or a polygonal cross-section.

6. Connection element according to one of claims 1 or 2, wherein the means for mechanical locking by at least one, arranged on the outer circumferential surface of the line portion latching hooks (40) are formed.

7. Connecting element according to claim 6, wherein a number of latching hooks (40) are provided, which are arranged distributed on the outer circumferential surface of the line section.

8. Connection element according to one of claims 1 to 7, wherein the sealing element by at least one O-ring

(38) is formed, which is arranged on the outer lateral surface of the line section and / or held.

9. Connecting element according to claim 8, wherein the O-ring

(38) is held in an annular groove (36).

10. Connecting element according to one of claims 1 to 9, which has an angled neck portion (28).

11. Connection element according to claim 10, which has a branch

(42) and two or more nozzle sections (28),

12. Connecting element according to one of claims 1 to 10, which is designed as a plastic part, in particular as a plastic injection molded part.

13. pressure fluid leading component, the at least one

Connection area for receiving and / or locking a connection element (10) according to one of claims 1 to 12.

14. The component according to claim 13, wherein the connection portion has at least one centering portion (22) with means for cooperating with the means (32, 40) for mechanical locking and at least one sealing portion (26) smaller inside diameter than the centering portion (22) for cooperation with the sealing element (36, 38).

15. The component according to claim 14, wherein the centering section (22) and / or the sealing section (26) are each formed as hollow cylindrical or conical.

16. The component according to claim 14 or 15, wherein between the sealing portion (26) and the centering portion (22). a hollow cone-shaped connecting portion (24) is provided.

17. The component according to one of claims 14 to 16, wherein at the bottom of the connection region, a line connection is provided which is at least partially aligned with the line section (18) of the connection element (10).

18. Hydraulic pump (44) with a connection element (10) according to one of claims 1 to 12 and with a component according to one of claims 13 to 17, wherein the connection element (10) is latched and / or glued in the connection region of the component.