Valve train of a reciprocating piston internal combustion engine

Abstract

A valve train for a reciprocating piston internal combustion engine with a transmission element in the form of a rocker arm (1) or pivot arm that can be actuated, on one hand, at least indirectly by a cam of a camshaft and is in active connection, on the other hand, through an intermediate connection of a valve bridge (4), with gas-exchange valves (7, 8). The valve bridge (4) has hydraulic valve lash compensation elements (HVAs) allocated to each gas-exchange valve (7, 8).

Claims

1. A valve train for a reciprocating piston internal combustion engine, comprising an arm that is actuatable at least indirectly by a cam of a camshaft, a valve bridge and gas exchange valves, the arm is in active connection with the gas-exchange valves through an intermediate connection of the valve bridge, hydraulic valve lash compensation elements provided in the valve bridge that are allocated to each of the gas-exchange valves, and a spherical head tappet and a spherical cup located on an end of the arm, wherein a pressurized medium line sequentially connects a pressurized medium hole in the spherical head tappet, an opening in the spherical cup, an extension formed in the valve bridge, the extension being in the form of a sphere or spherical section, and pressurized medium channels extending through the valve bridge to the hydraulic valve lash compensation elements.

2. The valve train according to claim 1, wherein the arm comprises a rocker arm or pivot arm.

3. The valve train according to claim 1, wherein the spherical cup contacts the valve bridge.

4. The valve train according to claim 1, wherein the arm includes a pivot bearing at the spherical head tappet.

5. The valve train according to claim 1, wherein the extension has a width greater than a width of the opening in the spherical cup to ensure passage of pressurized medium at all times between the spherical cup and the pressurized medium channels of the valve bridge.

6. The valve train according to claim 1, wherein the extension is positioned directly between the pressurized medium channels and the spherical cup.

7. The valve train according to claim 1, wherein the pressurized medium hole in the spherical head tappet extends partially through a height of the spherical head tappet such that a height of the spherical head tappet is greater than a height of the pressurized medium hole.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described in the detailed description below which should be read in conjunction with the drawings, in which:

(2) FIG. 1 shows a plan view of the end of a transmission element and a valve bridge,

(3) FIG. 2 shows a section through the end of the transmission element and through the valve bridge according to the line A-A in FIG. 1,

(4) FIG. 3 shows a section through the end of the transmission element with partial section through the valve bridge according to the line B-B in FIG. 1,

(5) FIG. 4 shows a section from the illustration according to FIG. 2 at an enlarged scale, and

(6) FIG. 5 shows a view corresponding to FIG. 3 also at an enlarged scale.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) In FIGS. 1 to 5, as far as shown in detail, 1 designates a rocker arm on whose end, in a hole, a spherical head tappet 2 is inserted that is in active connection with a spherical cup 3. The spherical cup 3 contacts a valve bridge 4 that includes, on each of its ends, a hydraulic valve lash compensation element 5 and 6. Because HVAs have already been generally known for a long time, they will not be discussed in more detail below. These are in active connection with gas-exchange valves 7 and 8. Starting from a pivot bearing 9 of the rocker arm 1, a pressurized medium line 10 is provided that leads to a pressurized medium hole 11 in the spherical head tappet 2 and from there to an opening 12 in the spherical cup 3. The opening 12 is in active connection with an extension 13 in the valve bridge 4, from which pressurized medium channels 14 and 15 lead to the hydraulic valve lash compensation elements 5 and 6. The hydraulic valve lash compensation elements 5 and 6 are thus reliably provided with pressurized medium, so that these adjust the existing lash to a specified measure for the typical movement of the rocker arm 1, the valve bridge 4, and the gas-exchange valves 7 and 8.

LIST OF REFERENCE SYMBOLS

(8) 1) Rocker arm

(9) 2) Spherical head tappet

(10) 3) Spherical cup

(11) 4) Valve bridge

(12) 5), 6) Hydraulic valve lash compensation element

(13) 7), 8) Gas-exchange valves

(14) 9) Swivel bearing

(15) 10) Pressurized medium line

(16) 11) Pressurized medium hole

(17) 12) Opening

(18) 13) Extension

(19) 14), 15) Pressurized medium channels