Intermediate lever for a variable-lift valve train of an internal combustion engine

Abstract

Proposed is an intermediate lever for a variable-lift valve train of an internal combustion engine, the upper portion of which has a pivot bearing, and the longitudinal middle section of which carries a rolling mechanism, which longitudinal middle section transitions on the underside into a base, which widens the intermediate lever at least on one side in the pivot direction thereof with a base bulge, and which has on the underside thereof a slide channel track for contact with a valve opener, wherein the intermediate lever has at the base bulge an abutment for the leg of a cam return spring, wherein the intermediate lever exists in the upper portion and the longitudinal middle section as a continuous flat, one-piece plate, wherein the pivot bearing is a bearing hole in the upper portion, wherein as a rolling mechanism two discs are provided in the longitudinal middle section, which discs each extend on a common shaft extending through it at the outer wall of the longitudinal middle section, and wherein the base is joined to the transversely thickened portion of the longitudinal middle section one piece below the discs.

Description

Technical Field

[0001] The present invention relates to a center rod for a variable lift valve train of an internal combustion engine, the upper portion of which has a pivot support for rotatably mounting on a carrier of the internal combustion engine, and the longitudinal center section of which carries a rolling mechanism for at least indirect reverse movement of a lifting cam. The longitudinal center section transitions into a base on the lower side, the base widening the center rod at least on one side by a base protrusion when viewed in its pivot direction, and the lower side of the base has a grooved track for contacting a valve opener, wherein the center rod has an abutment at the base protrusion for a leg of a cam return spring. Background Technology

[0002] This type of intermediate rod is derived from DE 10 2018 132 561A1. Its upper portion and longitudinal intermediate section are formed by two spaced-apart sidewalls, between which a rolling mechanism for the reverse movement of a "fliegenden" roller is accommodated. The roller is loaded during installation by a lifting cam and simultaneously by a cam disc. In the upper portion, each sidewall has a hole for support on a carrier of the internal combustion engine. Furthermore, the sidewalls in the upper section are connected by transverse bow-shaped members. Summary of the Invention

[0003] The aim is to develop an intermediate rod that is very simple to construct and can also be used in confined structural spaces.

[0004] According to the invention, the objective is achieved by the following manner: the intermediate rod exists as a continuous, flat, one-piece plate in the upper portion and the longitudinal intermediate section, wherein the pivot support is a support hole in the upper portion, wherein two discs are provided in the longitudinal intermediate section as a rolling mechanism, the discs extending on a common axis extending through the outer wall of the longitudinal intermediate section, and wherein the base is one-piece engaged with the transverse thickened portion of the longitudinal intermediate section below the discs.

[0005] Therefore, there exists a very simple, cost-effectively manufactured intermediate bar that is laterally positioned and requires relatively little structural space in the area between the two discs. Preferably, however not exclusively, the intermediate bar should be stamped from a metal strip. Its thickened bottom is achieved through a stamping and extrusion process. The process involves forging, pressing, or extrusion. The support hole on the bearing of the cylinder head of the internal combustion engine, used to pivotally suspend the intermediate rod, has the width of a metal plate. If necessary, it can also be widened in a raised manner or a separate sleeve can be used. Simultaneously, the support hole can be closed, exist as a hole, or also be "hook-shaped" open.

[0006] Alternatively, the entire intermediate rod body can also be manufactured using the MIM method or by stamping or extrusion. It may be sufficient to have only one disc as the rolling mechanism. The slide rail in the base can also be stamped. However, machining is also an option.

[0007] According to an improved embodiment of the invention, the end side of the base protrusion has a forked opening. The opening is integrally formed into the base protrusion and serves for the contact and guidance of the leg of the cam return spring. The opening can extend vertically or laterally, depending on the direction of action of the spring leg.

[0008] Although the upper part, together with the longitudinal middle section, can extend roughly orthogonally to the base, it has proven appropriate to surround it at an angle of 45° to 90° so that the functional parts do not collide with each other.

[0009] As a valve opener loaded by a center rod, a trailing rod or rocker arm is the first consideration. Alternatively, a rocker arm or tappet is also conceived. Attached Figure Description

[0010] Regarding the attached image:

[0011] Figure 1 A first perspective view showing the completed installation of the intermediate rod, and

[0012] Figure 2 This shows a view taken "from the front" relative to this rotation. Detailed Implementation

[0013] From the two figures, we can see that the intermediate rod 1 exists as a continuous, flat, one-piece plate in its upper portion 2 and longitudinal intermediate portion 5, and is integrally constructed of steel plate, i.e., together with its one-piece connected base 7. Therefore, the longitudinal intermediate portion 5 extends directly to the base 7.

[0014] The intermediate rod 1 has a pivot support 3 configured as an eyelet at its upper portion 2, for rotatably mounted on the load-bearing component 4 of the internal combustion engine. In the lower portion of its longitudinal intermediate section 5, at each outer wall 12, a disc 6 extends on a continuous shaft 13. A sliding or rolling support is provided here as a support mechanism. The two discs 6, which can also be referred to as narrow rollers, are used for the direct actuation of a "suspended" roller, which extends tensionally between a lifting cam and a cam disc.

[0015] If necessary, the intermediate rod 1 can also be adjusted by shifting the shaft of the so-called carrier of the internal combustion engine, the intermediate rod 1 extending on the shaft via its eyelet 3. Alternatively, a solution is also considered in which the cam acts directly on the disk 6 and the position of the camshaft carrying it relative to the intermediate rod 1 can be moved.

[0016] Below the two discs 6, the plate-shaped longitudinal middle section 5 transitions into a base 7 that widens relative to it, the base being formed by stamping. This is achieved. The raw materials may already have the thickened portion. The base 7 is widened on one side (labeled here as the left) via a base protrusion 8. A stamped grooved track 10 for contacting the valve opener is obtained on the lower side 9 of the base 7.

[0017] The base protrusion 8 has a one-piece, forked opening 4 at its end side 15, which extends vertically therein. The opening forms an abutment 11 for the support leg of the cam return spring, which extends along the height of the rod, and simultaneously guides it laterally.

[0018] The upper part 2, together with the longitudinal middle section 5, exists as a continuous straight finger-like member, said finger-like member being optimally positioned from... Figure 2 The angle between the thickened base 7 and the base 7 is slightly greater than 45°.

[0019] List of reference numerals in the attached diagram:

[0020] 1) Intermediate rod

[0021] 2) Upper part

[0022] 3) Pivot support, hole

[0023] 4) Opening

[0024] 5) Longitudinal middle section

[0025] 6) Rolling mechanism, disc

[0026] 7) Base

[0027] 8) The base is raised

[0028] 9) Lower side

[0029] 10) Slide rail

[0030] 11) Abutment part

[0031] 12)Outer wall

[0032] 13) Shaft

[0033] 14) Laterally thickened section

[0034] 15) End side

Claims

1. A middle rod (1) for a variable lift valve train of an internal combustion engine, the upper portion (2) having a pivot support (3) for rotatably mounted on a carrier (4) of the internal combustion engine, and the longitudinal middle section (5) thereon carrying a rolling mechanism (6) for at least indirect reverse movement of a lifting cam, the longitudinal middle section (5) transitioning to a base (7) on its lower side, the base (7) widening the middle rod (1) at least on one side by a base protrusion (8) when viewed in its pivot direction, and having a grooved track (10) on the lower side (9) of the base for contact with a valve opener, wherein the middle rod (1) has an abutment (11) at the base protrusion (8) for a leg of a cam return spring. Its features are, The intermediate rod (1) exists as a continuous, flat, one-piece plate in the upper part (2) and the longitudinal intermediate section (5), wherein the pivot support (3) is a support hole in the upper part (2), wherein two discs are provided in the longitudinal intermediate section (5) as a rolling mechanism (6), the discs extending on a common axis (13) extending through the outer wall (12) of the longitudinal intermediate section (5), and wherein the base (7) is one-piece engaged with the transverse thickening (14) of the longitudinal intermediate section (5) below the discs (6).

2. The intermediate rod according to claim 1, Its features are, The base protrusion (8) of the base (7) has a one-piece, forked opening (4) on its end side (15) as a resting part (11) for the support leg of the cam return spring.

3. The intermediate rod according to claim 1, Its features are, The upper part (2), the longitudinal middle section (5), and the base (7) of the intermediate rod (1) are made of steel plates.

4. The intermediate rod according to claim 1 or 3, Its features are, The lateral thickening of the base (7) is achieved by stamping and extrusion or by forging.

5. The intermediate rod according to claim 1, Its features are, The upper part (2), longitudinal middle section (5), and base (7) of the intermediate rod (1) are formed by extrusion.

6. The intermediate rod according to claim 1, Its features are, The upper part (2) and the longitudinal middle section (5) exist as continuous straight fingers, which are placed at an angle of 45° to 90° relative to the base (7).

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