BEAM-LIKE CROSSHEAD FOR A VALVE TRAIN OF A HEAVY-DUTY INTERNAL COMBUSTION ENGINE

Abstract

A beam-like crosshead for a valve train of an internal combustion engine is proposed for the transmission of a cam lift to two gas exchange valves. The crosshead has two side walls which are connected by a transverse wall, and, on an upper side of the transverse wall at its longitudinal center, a contact surface for a cam follower, and, on an underside of the transverse wall at each of its longitudinal ends, a valve contact surface. The crosshead is a reversed bowl-like hollow body which is produced from steel sheet using stamping/bending technology. From the transverse wall the side walls and, transversely at each longitudinal end, end walls hang in a finger-like manner. Cut edges between the side and end walls, starting from the transverse wall, form cut-outs.

Claims

1. A crosshead for a valve train of an internal combustion engine for a transmission of a cam lift to two gas exchange valves, the crosshead comprising: a body forming an inverted U-shape cross-sectional profile via bending of steel sheet, the body having: a first side wall connected to a second side wall via a transverse wall, a contact surface configured to engage a rocker arm or a camshaft, the contact surface formed on an upper side of the transverse wall, and a first valve contact surface and a second valve contact surface formed on an underside of the transverse wall, a first end wall configured as a first finger extending from a first longitudinal end of the transverse wall, and a second end wall configured as a second finger extending from a second longitudinal end of the transverse wall, and the first end wall is cut and separated from the first and second side walls such that first respective cut edges of the first end wall and the first and second side walls form first and second cut-outs, and the second end wall cut and separated from the first and second side walls such that respective second cut edges of the second end wall and the first and second side walls form third and fourth cut-outs.

2. The crosshead of claim 1, wherein the crosshead has a wall thickness of 2-10 mm.

3. The crosshead of claim 1, wherein the transverse wall includes a first plateau, a second plateau, a first rising section, a second rising section, and a longitudinal center section, and the first valve contact surface is formed on the first plateau, the second valve contact surface is formed on the second plateau, the contact surface is formed on the longitudinal center section, the first plateau is connected to the longitudinal center section via the first rising section such that a first elevation of the first plateau is different than an elevation of the longitudinal center section, and the second plateau is connected to the longitudinal center section via the second rising section such that a second elevation of the second plateau is different than the elevation of the longitudinal center section.

4. The crosshead of claim 1, wherein at least one of the contact surface or the first and second valve contact surfaces are formed via a coining process.

5. The crosshead of claim 1, wherein the first and second side walls each define a respective first free edge and a second free edge, the first and second free edges facing away from the transverse wall, and at least a portion of the first and second free edges has a constant elevation.

6. The crosshead of claim 5, wherein the first, second, third, and fourth cut-outs extend from the transverse wall.

7. The crosshead of claim 1, wherein the first and second end walls are formed via bending of sheet steel.

8. The crosshead of claim 1, wherein the first and second end walls, the first and second side walls, and the transverse wall form an inverted bowl.

9. The crosshead of claim 8, wherein the first end wall is arranged directly adjacent to the first valve contact surface, and the second end wall is arranged directly adjacent to the second valve contact surface.

10. The crosshead of claim 8, wherein the first and second end walls extend orthogonally relative to the contact surface.

11. The crosshead of claim 3, wherein the first and second end walls extend orthogonally relative to the longitudinal center section.

12. A crosshead for a valve train of an internal combustion engine for a transmission of cam lift to two gas exchange valves, the crosshead comprising: a body forming an inverted U-shape cross-sectional profile via cutting and bending of a single piece of sheet steel, the body having: a transverse wall having: an upper side formed with a contact surface configured to engage a rocker arm or a camshaft, an underside formed with a first valve contact surface and a second valve contact surface, a first side wall extending in a first direction from a first longitudinal side of the transverse wall, a second side wall extending in the first direction from a second longitudinal side of the transverse wall, a first end wall cut and separated from the first and second side walls, the first end wall extending in the first direction from a first longitudinal end of the transverse wall, and a second end wall cut and separated from the first and second side walls, the second end wall extending in the first direction from a second longitudinal end of the transverse wall.

13. The crosshead of claim 12, wherein the first end wall is directly adjacent to the first valve contact surface, and the second end wall is directly adjacent to the second valve contact surface.

14. The crosshead of claim 12, wherein first respective cut edges of the first end wall and the first and second side walls form first and second cut-outs, and second respective cut edges of the second end wall and the first and second side walls form third and fourth cut-outs.

15. The crosshead of claim 14, wherein the first, second, third, and fourth cut-outs extend from the transverse wall.

16. The crosshead of claim 12, wherein the transverse wall further comprises a first plateau and a second plateau, and the first valve contact surface is formed on the first plateau, and the second valve contact surface is formed on the second plateau.

17. The crosshead of claim 16, wherein the transverse wall further comprises a longitudinal center section, and the contact surface is formed on the longitudinal center section.

18. The crosshead of claim 17, wherein the transverse wall further comprises a first rising section and a second rising section and, the first plateau is connected to the longitudinal center section via the first rising section such that a first elevation of the first plateau is different than an elevation of the longitudinal center section, and the second plateau is connected to the longitudinal center section via the second rising section such that a second elevation of the second plateau is different than the elevation of the longitudinal center section.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In the drawings:

[0018] FIG. 1 shows a spatial view of the crosshead from above, and

[0019] FIG. 2 shows the crosshead as mentioned above in a view from below.

DETAILED DESCRIPTION

[0020] The figures disclose a beam-like crosshead 1 for a valve drive of a heavy-duty internal combustion engine, produced from thick-walled steel sheet (4-6 mm) using stamping/bending technology. The crosshead 1 is used to transmit a cam lift to two identically acting gas exchange valves that are located therebelow.

[0021] The inverted bowl-like, hollow crosshead 1 has two side walls 3 connected by an “overhead” transverse wall 2. On an upper side 4 of the transverse wall 2, at a longitudinal center of the crosshead 1, there is a flat and coined contact surface 5 for a rocker arm. On an underside 6 of the transverse wall 2, at each of its longitudinal ends 7, the crosshead 1 has a re-stamped or coined valve contact surface 8.

[0022] It can be seen that end walls 9 hang on the transverse wall 2 in a finger-like manner. These are designed separately from the side walls 3, wherein cut-outs 11 are present in the area of “upright” cut edges 10 between the side and end walls 3, 9, starting from the transverse wall 2. The end walls 9 have an approximately planar course and can be bent separately to form the side walls 3 when the final shape of the crosshead 1 is shown.

[0023] FIG. 2 best shows that the crosshead 1, seen in a side view and starting from both longitudinal ends 7, consists of a plateau 12 on each transverse wall 2, on the respective underside 6 of which the valve contact surface 8 is located. In the direction of the longitudinal center, the plateaus 12 each continue in a roof-like rising section 13, which sections 13 end in front of the longitudinal center and are connected via a flat piece 14 having the contact surface 5 on the upper side 4.

[0024] As finally shown in FIG. 1, a free edge 16 of the side walls 3 facing away from the transverse wall 4 is provided with a stiffness-increasing elevation 17 in the region of the longitudinal center. Areas of the edge 16 opposite the plateaus 12, on the other hand, are planar and run approximately parallel to the plateaus 12.

LIST OF REFERENCE CHARACTERS

[0025] 1) Crosshead

[0026] 2) Transverse wall

[0027] 3) Side wall

[0028] 4) Upper side

[0029] 5) Contact surface

[0030] 6) Underside

[0031] 7) Longitudinal end

[0032] 8) Valve contact surface

[0033] 9) End wall

[0034] 10) Cut edge

[0035] 11) Cut-out

[0036] 12) Plateau

[0037] 13) Section

[0038] 14) Flat piece

[0039] 15) Embossing

[0040] 16) Edge

[0041] 17) Elevation