Fuel distributor and pressure accumulator rail

Abstract

A fuel distributor which has a pressure accumulator rail for receiving pressurized fuel. The pressure accumulator rail has a forged base body. Mounting supports are joined to the base body by substance bonding. A mounting support is formed by two metal brackets each configured as a sheet-metal formed part. Each metal bracket has a holding portion adapted to the outer contour of the base body, a leg angled relative to the holding portion, and a mounting flange on the free end of the leg and angled away therefrom. A length portion of the base body is received between the holding portions. The holding portions partially surround the base body. The base body and the holding portions are joined by substance bonding. The legs of the two metal brackets lie next to each other at least in regions and are also joined together by substance bonding.

Claims

1. A fuel distributor, comprising: a pressure accumulator rail for receiving pressurized fuel; a forged base body having integral injector receivers; and a mounting support for mounting the pressure accumulator rail, the mounting support having two sheet-metal brackets, wherein each of the sheet-metal brackets comprises: a holding portion adapted to an outer contour of the forged base body, a leg angled relative to the holding portion, and a mounting flange at a free end of the leg and angled away therefrom, the holding portions are configured to receive a length of the forged base body therebetween, the holding portions partially surround the forged base body, the forged base body and the holding portions are joined by substance bonding, and portions of the legs of the sheet-metal brackets which lie next to each other are joined together by substance bonding.

2. The fuel distributor according to claim 1, wherein each of the holding portions surrounds the forged base body in cross-section over a peripheral region, wherein the peripheral region extends over an angle of between 90° and 180°.

3. The fuel distributor according to claim 2, wherein the peripheral region is an arcuate portion in which the holding portion and the forged base body are in mutual contact.

4. The fuel distributor according to claim 1, wherein the legs are arranged below the forged base body and extend substantially rectilinearly.

5. The fuel distributor according to claim 1, wherein at least one of the sheet-metal brackets has a slot cutout in a longitudinal direction.

6. The fuel distributor according to claim 1, wherein at least one of the mounting flanges has a mounting opening.

7. The fuel distributor according to claim 1, wherein at least one of the legs tapers, starting from a transition to the holding portion towards the mounting flange.

8. The fuel distributor according to claim 1, wherein at least one of the holding portions has a length, measured in a longitudinal direction of the forged base body, which is greater than the cross-section of the forged base body.

9. The fuel distributor according to claim 1, wherein the mounting support is arranged between two adjacent injector receivers among the injector receivers.

10. The fuel distributor according to claim 1, wherein at least one of the holding portions has a length measured in the longitudinal direction of the forged base body such that the holding portion covers at least 50% of the distance between two adjacent injector receivers among the injector receivers.

11. The fuel distributor according to claim 1, wherein at least one of the sheet-metal brackets has an S-shaped contour in a vertical cross-section.

12. The fuel distributor according to claim 1, wherein the sheet-metal brackets are identical to each other.

13. The fuel distributor according to claim 1, wherein each of the holding portions surrounds the forged base body in cross-section over a peripheral region, wherein the peripheral region extends over an angle of between 100° and 160°.

14. The fuel distributor according to claim 1, wherein each of the holding portions surrounds the forged base body in cross-section over a peripheral region, wherein the peripheral region extends over an angle of between 110° and 140°.

15. The fuel distributor according to claim 1, wherein each of the holding portions surrounds the forged base body in cross-section over a peripheral region, wherein the peripheral region extends over an angle of between 130°±5°.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure is described in more detail below with reference to an exemplary embodiment. The drawings show:

(2) FIG. 1 shows a fuel distributor according to the disclosure in a perspective view;

(3) FIG. 2 shows a fuel distributor in a top view;

(4) FIG. 3 is a vertical cross-section through the fuel distributor in the region of a mounting support;

(5) FIG. 4 is an end view of the fuel distributor;

(6) FIG. 5 shows a mounting support formed from two metal brackets in an end view;

(7) FIG. 6 shows a metal bracket in an end view;

(8) FIG. 7 shows the metal bracket illustrated in FIG. 6 in a side view; and

(9) FIG. 8 shows the metal bracket in perspective.

(10) In the figures, the same reference signs are used for identical or equivalent components, even if and when a repeat description is dispensed with for reasons of simplification.

DETAILED DESCRIPTION

(11) FIGS. 1 to 4 show a fuel distributor 1. The fuel distributor 1 belongs to the accumulator injection system of an internal combustion engine. Pressure generation and fuel injection are decoupled from each other in such accumulator injection systems. A separate high-pressure pump continuously generates pressure. This pressure, built up independently of the injection sequence, is permanently available in the fuel distributor 1.

(12) The fuel distributor 1 has a pressure accumulator rail 2 with a pump-side fuel inlet 3 and several stub-like injector receivers 4, 5. The statically compressed fuel is stored in the pressure accumulator rail 2 and made available to the injectors of a cylinder bank via the injector receivers 4, 5.

(13) The pressure accumulator rail 2 has a forged tubular base body 6.

(14) In the forging process, the stub-like injector receivers 4, 5 are formed integrally on the base body 6 from the same material. The stub-like fuel inlet 3 is also formed integrally on the base body 6 from the same material by forging. A longitudinal cavity 7 is made in the base body 6 by deep drilling.

(15) To fix or mount the fuel distributor 1 on a cylinder head of a motor vehicle, mounting supports 8 are provided.

(16) A mounting support 8 is formed from two metal brackets 9 configured as sheet-metal formed parts (see also FIGS. 5 to 8). The two metal brackets 9 are assigned to each other in pairs. The metal brackets 9 have sheet steel and have a wall thickness from 3 mm to 5 mm.

(17) On its upper end 10 on the base body side, a metal bracket 9 has a holding portion 11 adapted to the outer contour of the base body 6. A leg 12, which is angled relative to the holding portion 11, adjoins the holding portion 11. At the free end 13, i.e. the lower end of the leg 12 facing away from the base body 6, a mounting flange 14 is provided which is angled outward from the leg 12. A length portion 15 of the base body 6 is received between the holding portions 11 of the mounting support 8. The holding portions 11 partially surround the base body 6. The base body 6 and the holding portions 11 are joined by substance bonding, namely soldered. The legs 12 of the two metal brackets 9 overlap in regions and lie next to each other with mutual contact. In this contact region, the adjacent legs 12 are joined by substance bonding. This also takes place by soldering.

(18) The metal brackets 9 are designed as identical parts. In vertical cross-section, the metal brackets have an S-shaped contour as described above.

(19) A holding portion 11 surrounds the base body 6 in cross-section over a peripheral region U which, in the exemplary embodiment depicted here, extends over an angle α of 130°±5°. In principle, the peripheral region U may extend over an angle α of between 90° to 180°, or between 100° to 160°, or between 110° to 140°.

(20) The peripheral region U is an arcuate portion in which the holding portion 11 and the base body 6 make mutual contact.

(21) The two legs 12 of the metal bracket 9 or mounting support 8 are arranged below the base body 6 relative to the central longitudinal plane MLE, and extend linearly downward away from the base body 6 as far as the mounting flanges 14 which are bent outward at right angles. A mounting opening 16 is provided in each mounting flange 14 for passage of a fixing bolt. The mounting points are below the base body 6 and are partly covered by the base body 6 or holding portion 11 of the metal bracket 9 (see FIG. 2). To create a tool clearance and facilitate mounting of a fixing bolt, a cutout 17 oriented in the longitudinal direction L1 is provided in each metal bracket 9. The cutout 17 is formed as a slot and extends downward away from the holding portion 11 into the upper region of a leg 12. The cutout 17 functioning as tool clearance improves accessibility to the mounting point and fixing bolts, and facilitates the actual mounting process.

(22) The legs 12 of the metal bracket 9 taper, starting from the transition 18 to the holding portion 11, in the direction towards the mounting flange 14. In side view (FIG. 7), this gives a V-shaped or triangular design of the leg 12. The cutout 17 is arranged above the mounting flange 14. The transition 18 between the holding portion 11 and the leg 12 is rounded with a radius. At the free end 13 of the leg 12, the latter transforms—also rounded with a radius—into the outwardly angled mounting flange 14.

(23) The holding portion 11 of a metal bracket 9 has a length L measured in the longitudinal direction LR of the base body 6. Said length is greater than the outer cross-section Q of the base body 6. As evident in the depictions of FIGS. 1 and 2, a mounting support 8 is arranged between two injector receivers 4, 5 in the respective end region of the base body 6. The holding portions 11 have a length L in the longitudinal direction LR which covers at least 50% of the free distance A between the injector receivers 4, 5. The holding portions 11 may be made as wide as the installation space between the injector receivers 4, 5 and/or a pressure sensor connection 19 allows.

(24) The metal brackets 9 of a mounting support, which are assigned to each other in pairs, are arranged directly diametrically opposite each other relative to the base body 6 of the pressure accumulator rail 2. In the exemplary embodiments shown, as evident in FIG. 2, the metal brackets are arranged axially offset to each other in the longitudinal direction on opposing long sides 20, 21 of the base body 6.

(25) Produced by sheet-metal forming, the mounting supports 8 are configured as metal brackets 9 in the form of sheet-metal formed parts. This leads to a weight reduction of the fuel distributor 1. Furthermore, with this design, material-removal machining processes on the base body 6 are reduced or omitted. The fuel distributor 1 can bear high static and dynamic loads. This is guaranteed by the substance-bonded joint between the base body 6 and the mounting support 8, and the joint in the surrounding region of the metal brackets 9. Furthermore, the substance-bonded joint between the legs 12 of the metal brackets 9 increases the strength at the mounting points.

(26) The substance-bonded joints are created by a soldering process. For this, solder or solder paste is applied as required, and the soldering process is carried out with heat treatment in a temperature range between 850° C. to 1100° C. The heat treatment in the soldering process soft-anneals the pressure accumulator rail 2, which improves the mechanical machining and guarantees a lower tool wear. The heat treatment leads to a recrystalline material structure. The soldering process and heat treatment with subsequent cooling allows the omission of any pickling and passivation process. The corrosion resistance of the fuel distributor 1 is increased.

(27) The foregoing description of some embodiments of the disclosure has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise form disclosed, and modifications and variations are possible in light of the above teachings. The specifically described embodiments explain the principles and practical applications to enable one ordinarily skilled in the art to utilize various embodiments and with various modifications as are suited to the particular use contemplated. It should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the disclosure.