A hollow valve having optimized interior stem geometry, whose valve stem has surface-enlarging structuring on an inner surface is provided. Also provided is a method for manufacturing a valve body of such a hollow valve, wherein the method comprises: providing a bowl-shaped semi-finished product having an annular wall that surrounds a cavity, and having a base section, followed by lengthening the wall with an inserted, structured mandrel, and lastly, reducing an outer diameter of the annular wall without a mandrel to obtain a predetermined valve stem outer diameter of a valve to be manufactured.

A method for manufacturing an internally cooled valve (2), includes providing a valve body (4) having a valve stem (6) that ends in a valve head (8). The valve body (4) has a cavity (10) that is open toward the valve head (8) and with a valve base element (12) by friction welding the valve base element (12) to the valve head (8). The valve bottom element (12) is preferably a sintered component.

A method for manufacturing a poppet valve or mushroom valve includes providing a mixture of metal powder and a binder, filling and pressing said mixture in a mold, to obtain a green product, removing the binder from the green product, and thermally sintering the green product to a poppet valve blank, by hot isostatic pressing. A poppet valve is also provided that is manufactured with this method.

A poppet valve includes: a valve body comprising a valve stem body, a valve head body with a valve combustion face, and a valve fillet body interconnecting the valve stem body and the valve head body. The valve fillet body surface has an increased thermal resistance compared to the valve combustion face.

The disclosure relates to a hydraulic unit of an electrohydraulic gas exchange valve control system of an internal combustion engine. The hydraulic unit includes a hydraulic housing having a receiving opening, a piston guide, and a slave piston. The piston guide is fastened in the hydraulic housing by way of self-staking with a wall of the receiving opening. The piston guide includes an outer part that brings about the self-staking and an inner part that guides the slave piston. An inner surface of the outer part is radially interspaced from the outer surface of the inner part in an axial region of the self-staking and the outer part and the inner part are connected in an axially form-locked manner so that a first end section of the outer part facing the gas exchange valve is partially or fully formed into an outer circumferential recess of the inner part.

This strain wave gear unit includes: a bottomed cylindrical first internal gear having internal teeth formed on a cylindrical part and a teeth-non-formed part protruding farther inward than the tooth bottom of the internal teeth in a corner area where a bottom wall part is integrally connected to the cylindrical part; a flexible cylindrical external gear having external teeth meshing with the internal teeth of the first internal gear, an opposed part opposed to the teeth-non-formed part with a gap therebetween, and an end part opposed to the bottom wall part to make contact therewith; a second internal gear arranged adjacent to the first internal gear and having internal teeth meshing with the external teeth; and a rotation member that causes the external gear to deform in an oval shape and causes the meshing position to move while partially meshing with the first internal gear and the second internal gear.

A method of cold forming an outer arm of a rocker arm assembly in a cold forming machine includes providing a slug having a first end and a second end, extruding the slug at the first end to establish two different widths of the slug, compressing the slug to form an upper angled surface and a lower angled surface at the second end, and compressing the slug to form an inner arm window defined by a pair of side walls and a pair of end walls.

A method for manufacturing a hollow camshaft is provided, and more particularly, a method for manufacturing a combined hollow camshaft by an axial-compression upsetting-deformation technique. The present method solves a problem that the current camshaft manufactured in an internal high-pressure expansion manner in the prior art has the insufficient locking force to cause the loosening of a cam. The method is as follows: a camshaft is formed by combining two independent units, namely a cam and a shaft tube. Non-circular countersinks are distributed on two sides of the cam. Thrust steps are formed on the shaft tube correspondingly. The cam is placed between the two thrust steps of the shaft tube. The locking force is applied to the cam by utilizing the thrust steps on the two sides of the cam based on thermal expansion and contraction. Simultaneously, the thrust steps lock the cam with the countersinks.

Provided is a sealing apparatus that can prevent a garter spring from falling off an elastic member. The sealing apparatus comprises a reinforcing ring formed annularly around an axis, an elastic body part that is attached to the reinforcing ring and that is formed annularly around the axis, and a garter spring attached to the elastic body part. The reinforcing ring includes a retainer that is an annular portion projecting to an outer periphery side from an end portion on one side of the reinforcing ring in a direction of the axis. The elastic body part has at least one projection that is formed on the one side of a zone to which the garter spring is attached in the direction of the axis and that projects from the elastic body part to the outer periphery side.

Provided is cladding alloy powder that can keep enough corrosion resistance of the cladding portion on the engine valve and can suppress adherence of the cladding portion to the valve seat. Cladding alloy powder is to form a cladding portion at an engine valve that comes in contact with a valve seat of an engine. The cladding alloy powder includes 22 to 27 mass % of Cr; 10 to 30 mass % of Mo; 2.0 to 6.0 mass % of W; 0.40 to 1.30 mass % of C; 3.0 mass % or less of Si; 15.0 mass % or less of Ni; 30.0 mass % or less of Fe; and 0.4 mass % or less of S as well as Co and unavoidable impurity as a remainder, and satisfies Cr(−0.53C+1.2)+Mo(−1.2C+2.8)≥24 and 23W+2.7Mo≥73.