Valve clearance adjustment systems and related methods that can be used to quickly and easily establish and accurately fix a desired and consistent and replicable valve clearance gap in internal combustion engines with shaft mounted rocker arms where a manual valve lash adjustment is required. In some examples, valve adjustment systems include valve adjustment members that are movably disposed in rocker arms and that can be easily and selectively fixed in place in the rocker arm. Aspects also include indexing mechanisms (734, 822, 838) for quickly and easily setting a desired position of a valve adjustment screw in a rocker arm without needing to use a feeler gauge.

Provided is a valve seat insert for an internal combustion engine, which has both an excellent heat dissipation property and excellent wear resistance. The valve seat insert for an internal combustion engine is used while being press-fitted into an aluminum alloy cylinder head, is made of an iron-based sintered alloy, is formed by integrating two layers of a functional member side layer and a supporting member side layer, and has a plating film on at least an outer peripheral side. The plating film is preferably a copper plating film. The plating film is a plating film having a thickness of 1 to 100 μm and a hardness of 50 to 300 HV, and the hardness of the plating film is adjusted so as to satisfy a range of 1.05 to 4.5 times hardness of the cylinder head in Vickers hardness HV. Pores contained in the valve seat insert are preferably sealed with a curable resin before plating treatment. Consequently, a valve seat insert for an internal combustion engine which does not go through complicated processes, is not accompanied by a significant decrease in wear resistance compared with the prior art, and has an excellent heat dissipation property is provided. If a roughened surface region is further formed at at least one portion on the outer peripheral surface of the valve seat insert in addition to the plating film, a falling out resistance property is improved. The same effect can be obtained even if the valve seat insert is a single layer of only the functional member side layer.

A method for manufacturing an engine poppet valve having a valve head portion and a stem portion made integral by way of a neck portion that increases in diameter toward a tip end, comprising: a valve head portion manufacturing operation in which hot forging is employed to form a stem/head intermediate product comprising an intermediate stem portion and a valve head portion which is made integral with the intermediate stem portion by way of a neck portion; a stepped stem portion manufacturing operation in which cold drawing in which a part of the intermediate stem portion is inserted in press-fit fashion from a base end portion into a stem member inlet surface and a stem member compressing surface of a hollow circular hole die that has a drawing hole and at which the stem member inlet surface that gradually narrows toward a central axis, and the stem member compressing surface that is continuous with the stem member inlet surface and that has a constant inside diameter which is less than an outside diameter of the intermediate stem portion are provided at least at a portion thereof is employed to cause a stepped stem portion comprising a first stem portion which has been made to be of decreased diameter, a step portion which has been formed by the stem member inlet surface, and a second stem portion in which there is absence of decrease in diameter and which is continuous by way of the step portion with the first stem portion to be formed from the intermediate stem portion; and a joining operation in which a stem end portion having a same outside diameter as the first stem portion is joined to a base end portion of the first stem portion.

An apparatus for assembling an engine includes an engine jig configured to load the engine on which a pump sprocket, a cam sprocket, an auto tensioner, and an engine belt are preliminarily mounted. The apparatus includes: a pump sprocket fastening unit disposed on a first die disposed on a first side of the engine jig and configured to clamp and fully fasten the pump sprocket in order to fixedly mount the pump sprocket preliminarily mounted to the engine; a cam sprocket fastening unit disposed on the first die and configured to clamp, rotate, and fully fasten the cam sprocket in order to fixedly mount the cam sprocket preliminarily mounted to the engine; and an auto tensioner fastening unit disposed on the first die, and configured to clamp, rotate, and fully fasten the auto tensioner in order to fixedly mount the auto tensioner preliminarily mounted to the engine.

An apparatus includes a bearing assembly of a first camshaft and a second camshaft on a cylinder head of an internal combustion engine. The first camshaft has a first recess where a tool is insertable into the first recess and the second camshaft has a second recess where the tool is insertable into the second recess. A cylinder head hood is attached to the cylinder head where the cylinder head hood has a first through-opening matched with the first recess and a second through-opening matched with the second recess. A first wall area of the cylinder head hood that at least partially delimits the first through-opening and a second wall area of the cylinder head hood that at least partially delimits the second through-opening are disposed at different heights.

A valve timing adjustment device includes: a housing member; a vane rotor that includes vanes and is securely coupled to a driven shaft and is rotatable relative to the housing member when the vane rotor receives a pressure of hydraulic oil introduced into hydraulic chambers; a fixing member that fixes the vane rotor to the driven shaft; and a bearing section that rotatably supports the housing member. The housing member includes a winding section that is formed at an outer peripheral surface of the housing member. A transmission member is wound around the winding section. The bearing section and the winding section at least partially overlap with each other when viewed in a direction perpendicular to an axial direction.

At a diameter-decreasing operation during manufacture of a poppet valve, an intermediate stem portion at which a valve head portion and an intermediate stem portion are made integral by way of a neck portion may be inserted between/among diameter-decreasing tools. Application of compressive forces from compressing surfaces of the diameter-decreasing tools may cause a part of the intermediate stem portion to be decreased in diameter and may cause a main body portion of a first stem portion to be formed and may cause formation of a stepped portion which is continuous with the main body portion, and formation, by an absence of decrease in diameter, of a second stem portion which is broader in girth than the main body portion and which is continuous with the neck portion and which is also continuous with the main body portion by way of the stepped portion.

A method for shaping a hollow valve preform of a pull rod (20) includes a structuring bulb (22) which is inserted into the cavity (56) of a shaft portion (44) of a valve preform. The structuring bulb (22) has an outer diameter, and has an outer structuring, whereafter the hollow shaft portion (44) is shaped, wherein at least a portion of an inner diameter of the cavity (56) is reduced below an outer diameter of the structuring bulb (22). The structuring bulb (22) is then pulled out through the shaped shaft portion (44), wherein the outer structuring is at least partially pressed into the surface of the cavity (56).

The invention relates to a flexible transmission components for a harmonic drive comprising a resilient toothing element formed as a sheet metal part and having external toothing, and a printed circuit board bonded to the toothing element.

An apparatus is provided to test valves. The apparatus includes a support structure and a plurality of engagement members coupled to the support structure. Each member of the plurality of engagement members is coupled with a valve of a valve train associated with an engine head. The apparatus further includes a camshaft, which includes a plurality of lobes coupled to the support structure. Each lobe of the plurality of lobes are equally spaced from each other and coupled to a member of the plurality of engagement members. The apparatus further includes a driving mechanism coupled to the camshaft, which is configured to rotate the camshaft and control each member of the plurality of engagement members to further control an activation of each valve of the valve train associated with the engine head.