Abstract:
A rocker arm assembly for use in internal combustion engines comprising a rocker arm member having a longitudinal extent and including bearing means for mounting the member for oscillation about an axis perpendicular to its longitudinal extent. An insert body defining a push rod seat recess is press fitted in an end of the rocker arm member to extend transversely to the axis of oscillation. The insert has a first generally cylindrical end portion of a first diameter and a second axially aligned generally cylindrical end portion of a smaller diameter. The first end portion is spaced from the second end portion by an intermediate transition surface which is inclined relative to the axis of the cylindrical end portions. The push rod seat recess extends axially into the first end of the body. The relationship of the insert end portions and the transition surface prevents loosening of the insert in the rocker arm body.
Abstract:
A rocker arm and method of making same are provided. The rocker arm is of the cam-follower type and includes a metal body preferably made from a stamped metal piece and a stamped metal strip. A rounded recess is formed at one end portion of the metal piece and facing away from the metal strip to receive a lifter post having an end on which the rocker arm can pivot. The metal piece also has an additional recess at another end portion to receive an end of a valve stem and the metal strip has an intermediate convex portion facing away from the metal piece. The metal piece has a hole extending therethrough and communicating with the rounded recess, while the strip forms an oil passage communicating with the hole and extending toward the convex portion to supply lubricating fluid between the convex portion and the rounded recess. The convex portion has a shallow recess in which is received a hardened metal insert to be engaged by a cam. A softer metal layer is preferably in the shallow recess below the hardened insert. The insert is preferably affixed in the shallow recess by laser welding the ends of the insert to edges of the shallow recess.
Abstract:
A rocker arm and method of making same are provided. The rocker arm is of the cam-follower type and is preferably made from a stamped metal piece and a stamped metal strip, the latter preferably being of a hardened alloy. A rounded recess is formed at one end portion of the metal piece and facing away from the metal strip to receive a lifter post having an end on which the rocker arm can pivot. The metal piece also has an additional recess at another end portion to receive an end of a valve stem. The metal strip has an intermediate convex portion facing away from the metal piece to be engaged by a cam. The metal piece has a hole extending through the piece and communicates with the rounded recess while the strip forms a groove communicating with the hole and extending toward the convex portion to supply lubricating fluid from the convex portion to the rounded recess. After the metal piece and the strip are partially stamped, end tabs thereon are welded together and the contiguous portions are brazed, further stamped, and finish formed. The end tabs are then removed and the resulting rocker arm is heat treated and cleaned to complete the process.
Abstract:
This invention is made with a view to increasing the fusing strength of an end piece in a valve moving push rod for internal combustion engines. The fusing part of the push rod according to the present invention consists of an .alpha.-martensite structure and a primary truestite structure in a cotransition boundary range of a segmental section formed into the hardened layer of the end piece from the fused boundary surface of the end piece with a tube end part and is provided with a tough mixed layer arcuated from the inside end part of the above mentioned fused boundary surface to the outside end part thereof. This mixed layer is obtained by reducing by a heat feeding means a quick temperature drop caused by the fusing part simultaneously with cutting off the fusing current in welding by electric resistance the end piece on the fixed side surface to the peripheral edge of the end port of a tube material. Such crack as is recognized in the fusing part of a conventional product is not recognized in a product obtained by reducing the quick cooling by this method.
Abstract:
A cam follower is constituted by an outer ring which has an outer track surface in its inner circumference; a stud which has an inner track surface opposed to the outer track surface, a flange portion abutting on one side of the inner track surface, a side plate fitting portion and a mounting shaft portion abutting on another side of the inner track surface in this order, and a fiber flow formed continuously from the flange portion to the inner track surface along their outer circumferences; rolling elements which are arranged between the outer track surface and inner track surface; and an inner side plate which is pressed into the side plate fitting portion to work with the flange portion for limiting axial movement of the outer ring and the rolling elements.
Abstract:
A mechanical system comprising: a tappet, including a body; an insert mounted in the body; a pin extending along a first axis; and a roller element movable in rotation relative to the pin around the first axis. The insert supports the pin, while the body supports the insert, along at least one first direction parallel to a second axis which is perpendicular to the first axis. The mechanical system can be integrated into an injection pump and/or a valve actuator.
Abstract:
A mechanical system, comprising a tappet including a body, a support element defining two bores centered on a first axis, a pin comprising two opposite ends each adapted to be fitted in one of the two bores, and a roller element positioned between the two bores along the first axis and movable in rotation relative to the pin around the first axis. The support element is distinct from the body and fixed thereto, and the support element also comprises at least one antirotation device integrally formed thereto. The mechanical system can be integrated into an injection pump and/or a valve actuator.
Abstract:
A method of manufacturing spring pallets of a switchable roller finger follower. The method includes the steps of forming the spring pallets of the roller finger follower as a single unit, forming a material web between the spring pallets, and separating the spring pallets apart from each other. Also, an intermediate assembly of the spring pallets of the roller finger follower is disclosed. The intermediate assembly includes a first spring pallet, a second spring pallet, and a material web which extends between the spring pallets, and adjoins the spring pallets together. Further, a method of manufacturing an inner arm of the switchable roller finger follower is disclosed in which the inner arm is formed by sheet metal, preferably by stamping.
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.