Abstract:
The present invention provides a rocker arm manufacturing method capable of stably forming valve stem guide walls. In the method according to the present invention, an intermediate product 13 having both side walls 20 extended in a predetermined direction and arranged in parallel with each other and a one end side connection wall 30 connecting lower ends of both the side walls 20 at a longitudinal one end of the product is obtained. Next, a first pressing punch 70 is pressed against the outer surface portions of both the side walls 20 from the outside thereof to cause downward plastic flows of regions of the outer surface portions of both the side walls positioned below the cutout portions 31 to thereby form raising walls 32 in a downwardly protruded manner at both sides of the one end side connection wall 30. Thereafter, valve stem guide walls 35 are formed by pressing second pressing punches 80 against both the raising walls 32 of the one end side connection wall 30.
Abstract:
An engine assembly may include an engine structure supporting a camshaft and a valve lift mechanism. The camshaft may include a cam lobe and may define a longitudinally extending rotational axis. The valve lift mechanism may define a longitudinally extending cam engagement surface and a first side wall. The cam engagement surface may be engaged with the cam lobe at a first location. The first side wall may be fixed to the cam engagement surface and may include first and second portions. The first portion may extend from the cam engagement surface. The second portion may extend continuously inward from an end of the first portion. The inward extent of the second portion may be greater than or equal to a first height at the first location defined from the cam engagement surface to the end of the first portion.
Abstract:
An inner lever (1) for a switchable finger lever (2) of a valve train of an internal combustion engine is provided, having a box-like main part (5) with two lateral walls (6), which are connected at a first end (7) by a transverse bar (8), which intrinsically includes a driver surface (9) for a coupling slide that can be guided longitudinally by the outer lever (3), and opposite from the first end (7), the lateral walls (6) have two strongly crimped together, thin-walled arms (10), which each extend in the direction toward the second end (11) of the inner lever (1) to form a longitudinal bar (12). The arms contact each other with their inner sides (15), and between the lateral walls (6), a cam contact surface (16) can be provided. The inner lever (1) made from thin-walled steel sheet metal at least to a large extent using punch-bending techniques.
Abstract:
A corrosion-resistant alloy tube is formed and bonded to a pre-machined steel alloy rod to form a riser tensioner cylinder rod. During assembly, an epoxy is injected into an annular space between the tube and rod and then cured. The bonded tube is ground to a desired surface finish prior to installation and utilizes a double seal arrangement that prevents external pressure or corrosive fluids from entering the cured epoxy in the annular space.
Abstract:
A rocker arm formed of material in a shape of sheet has a pair of side wall portions, a connection portion for a valve stem receiving portion and a connection portion for a pivot receiving portion which interconnect the side wall portions, and an open portion for arranging a roller which is formed between the two connection portions. A distance between outer side surfaces of the pair of side wall portions in the connection portion for the valve stem receiving portion is reduced in a direction from upper edges to lower edges in a step-like shape having two or more step differences, whereby a first outer side surface and a second outer side surface are formed.
Abstract:
A rocker arm configured to be supported by a support portion of an internal-combustion engine and to be driven in a swinging manner by a cam. The rocker arm includes a rocker arm body including a cam follower having a first slide-contact surface, wherein the first slide-contact surface is in sliding contact with the cam, a fulcrum portion including a second slide-contact surface, wherein the second slide-contact surface swingably is in sliding contact with respect to the support portion, and a lubricant discharging portion for biasing a lubricant supplied from the fulcrum portion in a direction toward the first slide-contact surface and discharging the lubricant. The fulcrum portion penetrates the rocker arm and is fastened to the rocker arm body. The fulcrum portion has a through hole supplying the lubricant to the lubricant discharging portion through the rocker arm body.
Abstract:
A rocker arm includes a first end including a substantially horizontal wall having a receptacle formed therein. A second end of the rocker arm is spaced from the first end and includes a substantially horizontal wall for engaging a valve stem. A pair of spaced substantially parallel vertical sidewalls extend between the first end and the second end. In one embodiment, the sidewalls define a width between the first end and the second end that is less than each of the widths of the first and second ends. In another embodiment, a transverse wall extending between the sidewalls is formed in the second end. In yet another embodiment, rocker arm alignment walls are formed in the second end independently of the sidewalls.
Abstract:
The lever (11) is fitted with two rollers (20A, 20B) which are supported by a core (21) provided with a mounting bore (21B) on an articulated shaft, wherein the rollers (20A, 20B) are both mounted between two webs of a pair of webs which are added to the core (21). The webs (22A, 23B) are on the whole planar. A first web (22A) of each pair of webs is partially engaged in a hollow housing (21C) created on the lateral surface (21D) of the core (21). The second web (23B) of the same pair is maintained at a distance from the first web. The hollow housings (21C) are created on the two opposite lateral surfaces (21D) of the core (21) of the lever (11).
Abstract:
A rolling bearing for a rocker arm includes an outer ring in rolling contact with a cam of an engine, an outer-ring shaft placed inside the outer ring and fixed to the rocker arm, and a plurality of rollers provided between the outer ring and the outer-ring shaft. At least one of the outer ring, the outer-ring shaft and the rolling elements has a nitrogen-rich layer, an austenite crystal grain size number in a range exceeding 10, and a surface hardness Hv of at least 653. Thus, the life can be extended.
Abstract:
In a gas exchange valve operating apparatus with at least one overhead camshaft for actuating the gas exchange valves, with a hydraulic medium supply passage extending through the camshaft and with at least one hydraulic switchable support unit cooperating with a lever-like cam follower which is disposed on a switchable support unit and on a gas exchange valve and is furthermore in contact with the overhead camshaft, the support unit is disposed in communication with at least one pressure medium supplied via the hydraulic medium supply passage of the camshaft.