High-pressure fuel pump and pressure control device
View Patent ↗The present disclosure relates to a device for pressure control, including a rod and a plunger. The rod has a first end region delimiting a pressurized space and is movable along an axis between a top dead center and a bottom dead center. The plunger has a traverse substantially perpendicular to a plunger axis transmitting kinetic energy from a plunger drive to the rod in a contact region between a traverse surface and a second end region of the rod arranged opposite the first end region. The rod includes a calotte-shaped end region in the contact region of the rod and the traverse includes a calotte-shaped recess in the contact region of the traverse.
1. A high-pressure pump for pressurizing a fuel, the high pressure pump comprising:
a piston movable along a piston axis between a top dead center and a bottom dead center,
a plunger with a traverse arranged substantially perpendicular to a plunger axis and transmitting kinetic energy from a plunger drive to the piston in a contact region between a traverse surface and an end region of the piston,
wherein the piston includes a calotte-shaped end region in the contact region of the piston, and the traverse includes a calotte-shaped recess in the contact region of the traverse;
wherein a recess radius of the calotte-shaped recess of the traverse is at least twice a piston end radius of the calotte-shaped end region of the piston.
2. A device for influencing a pressure in a medium, the device comprising:
a rod with a first end region delimiting a space filled with the medium, the rod movable along a rod axis between a top dead center and a bottom dead center;
a plunger having a traverse arranged substantially perpendicular to a plunger axis for transmitting kinetic energy from a plunger drive to the rod in a contact region between a traverse surface and a second end region of the rod arranged opposite the first end region;
wherein the rod includes a calotte-shaped end region in the contact region of the rod and the traverse includes a calotte-shaped recess in the contact region of the traverse; and
wherein a recess radius of the calotte-shaped recess of the traverse is at least twice a rod end radius of the calotte-shaped end region of the rod.
3. The device as claimed in claim 2 , wherein the traverse includes a traverse surface in regions adjoining the calotte-shaped recess, the traverse surface having planar form substantially perpendicular to the plunger axis.
4. The device as claimed in claim 2 , wherein the calotte-shaped recess is formed into the traverse surface by stamping.
5. The device as claimed in claim 2 , wherein the calotte-shaped recess is arranged symmetrically about an axis which bisects the traverse perpendicularly to the longitudinal axis thereof.
6. The device as claimed in claim 2 , wherein the traverse is movable radially with respect to the plunger axis, wherein the traverse is inserted into the plunger without radial fastenings.
7. The device as claimed claim 2 , further comprising a rod guide having a rod guide axis,
wherein a rod end radius of the calotte-shaped end region of the rod is smaller than or equal to a spacing at the top dead center of the rod, between a tangent to a rod calotte surface at the rod axis and an intersection point of the plunger axis and the rod guide axis.
8. The device as claimed claim 2 , further comprising a rod guide having a rod guide axis,
wherein a rod end radius of the calotte-shaped end region of the rod is greater than a spacing, which exists at the top dead center of the rod, between a tangent to a rod calotte surface at the rod axis to an intersection point of the plunger axis and the rod guide axis,
wherein a recess radius of the calotte-shaped recess of the traverse is greater than a rod end radius of the calotte-shaped end region of the rod, to such an extent, in the case of identical materials being used, that the Hertzian stress is situated in the region of contact between a planar traverse surface and a calotte-shaped end region of the rod.
9. A valve for an internal combustion engine, the valve comprising:
a rod with a first end region delimiting a space filled with a fuel, the rod movable along a rod axis between a top dead center and a bottom dead center to open an engine valve;
a plunger having a traverse arranged substantially perpendicular to a plunger axis for transmitting kinetic energy from a plunger drive to the rod in a contact region between a traverse surface and a second end region of the rod arranged opposite the first end region;
wherein the rod includes a calotte-shaped end region in the contact region of the rod and the traverse includes a calotte-shaped recess in the contact region of the traverse; and
wherein a recess radius of the calotte-shaped recess of the traverse is at least twice a rod end radius of the calotte-shaped end region of the rod.