U.S. patent application number 11/688347 was filed with the patent office on 2008-09-25 for rocker arm with integral internal oil passages.
This patent application is currently assigned to GenTek Technologies Marketing Inc.. Invention is credited to Thomas C. Edelmayer.
Application Number | 20080229578 11/688347 |
Document ID | / |
Family ID | 39766737 |
Filed Date | 2008-09-25 |
United States Patent
Application |
20080229578 |
Kind Code |
A1 |
Edelmayer; Thomas C. |
September 25, 2008 |
ROCKER ARM WITH INTEGRAL INTERNAL OIL PASSAGES
Abstract
A rocker arm and method for manufacture is provided whereby the
rocker arm is manufactured in two halves generally symmetric to a
central plane. The mating surface of one or both rocker arm halves
incorporate grooves which upon assembly provide passageways which
may follow any desired pathway for lubricant and or afford a
reduction in mass and/or an increase in structural stiffness. The
two halves are preferably joined together by metallurgical brazing
or by other chemical or mechanical means.
Inventors: |
Edelmayer; Thomas C.;
(Canton, MI) |
Correspondence
Address: |
ARTHUR J. PLANTAMURA, ESQ.;GENERAL CHEMICAL PERFORMANCE PRODUCTS LLC.
90 EAST HALSEY ROAD
PARSIPPANY
NJ
07054
US
|
Assignee: |
GenTek Technologies Marketing
Inc.
Westfield
MI
|
Family ID: |
39766737 |
Appl. No.: |
11/688347 |
Filed: |
March 20, 2007 |
Current U.S.
Class: |
29/888.2 |
Current CPC
Class: |
F01L 2303/00 20200501;
F01L 1/18 20130101; Y10T 29/49295 20150115; F01L 1/181 20130101;
F01L 1/2411 20130101; F01M 9/107 20130101; F01L 2305/00 20200501;
F01L 2305/02 20200501 |
Class at
Publication: |
29/888.2 |
International
Class: |
B21D 53/84 20060101
B21D053/84 |
Claims
1. A method of making a sintered metal rocker arm from
complimentary pre-fabricated mating sections of metal powder
wherein at least one of said sections contains an integral formed
lubricant passageway, and bonding said section to form the rocker
arm product containing therein the integrally formed internal
passageway.
2. The method of claim 1 wherein the rocker arm is made by joining
two complimentary half-sections.
3. The method of claim 2 wherein the lubricant passageway is
contained entirely within one or more of the pre-fabricated
sections.
4. The method of claim 2 wherein the lubricant passageway is formed
when the complimentary sections are mated and bonded together.
5. The method of claim 1 wherein the two complimentary
half-sections are comprised of a powdered metal alloy.
6. The method of claim 1 wherein the section are comprised of
powdered metal selected from iron and iron alloys.
7. The method of claim 1 wherein the sections are bonded by
metallurgical brazing.
8. The rocker arm produced by the method of claim 1.
9. The rocker arm produced by the method of claim 4.
10. The rocker arm produced by the method of claim 6.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a rocker arm and method for
making a rocker arm for an internal combustion engine having
internal oil passages. More particularly, the invention relates to
an improved rocker arm having internal oil passages formed by
joining pre-fabricated sections that have oil passages as an
integral feature of at least one of the sections.
BACKGROUND OF THE INVENTION
[0002] Conventional methods for manufacturing rocker arms generally
involve stamping or casting procedures. The formed pieces are
thereafter processed to remove material by machining e.g. drilling,
milling, etc. to form oil passages in the rocker arm. Such methods
by machining, drillings, milling, etc. require the removal of
material to create the necessary oil passages. Additionally,
passages formed in that manner are often less precise in dimensions
and location. Also, prior art drilling or machining of oil
passages, as a practical matter, must comprise a straight line and
be of a size compatible with the drilling process and cannot take
the form of a "worm" groove formed so as to provide the optimum
advantage. Additionally, deeper holes, e.g. those in excess of
about 10 drill-diameters deep, require the use of slower,
relatively costly drilling process i.e., gun drilling. A method for
production which pre-fabricates sections and the resulting product
with precisely formed and located oil passages and joins such
sections to form a finished rocker arm would be advantageous in
cost and time savings.
SUMMARY OF THE INVENTION
[0003] The novel rocker arm of the invention is characterized by
joining the pre-fabricated sections of sintered metal particles,
generally two halves that are symmetrical to a central plane and
wherein the mating surfaces of one or both halves incorporate
grooves which upon assembly form one or more passageways for oil.
The resulting product results in a significant reduction in mass
and is found to produce an increase in structural stiffness. The
pre-fabricated sections, preferably of powdered metal composition,
are joined together by any convenient known technique such as by
metallurgical brazing or by chemical or mechanical means.
BRIEF DESCRIPTION OF THE FIGURES
[0004] FIG. 1 is a perspective view of the rocker arm assembly
formed by joining two separated preformed parts as contemplated by
the invention mounted on a rocker shaft (not shown) and an
hydraulic lash adjuster cartridge installed therein.
[0005] FIG. 2 is a perspective view of two pre-fabricated
mirror-image sections of the rocker arm of the invention.
[0006] FIG. 3 is a perspective view of the assembled sections show
in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
[0007] The rocker arm of the invention comprising the
pre-fabrication of separate mating sections, preferably two
sections, is manufactured conveniently such as by furnace brazing
together the sections, preferably formed of a powdered metal and
containing integrally formed grooves in one or both mating
sections. Additional machining or drilling to form internal
passageways is avoided.
[0008] The metal is atomized by methods in which a stream of molten
metal is struck with air or water jets and the formed metal
particles are collected, sieved and annealed. In processing, the
powdered metal particles, including mixtures of different metals,
are shaped into the desired suitable form such as by flowing the
metal powder usually at room temperature into a die cavity shaped
as the finished part, and then applying pressure from above and
below to form a compact. After ejection from the die, the compact
is heated (sintered) to form a coherent mass with the configuration
of the original die and properties related to the metals used. The
pressure applied affects the density as well as the strength of the
formed piece; the greater pressure the higher the strength. A low
density porous compact may be formed by pouring the powder into a
die and then heating it without first applying pressure. The shape
and size of the die cavity can be exactly as required by the
finished part. However, if desired, this invention contemplates the
use of any suitable metal or metal alloy powder and preferable
powders of iron or iron alloys.
[0009] Referring to the drawings, FIG. 1 illustrates an essentially
completely assembled rocker arm 20 comprising the rocker arm body
22, a hydraulic lash adjustment cartridge 24, roller bearing 26,
and roller bearing axle 28.
[0010] Referring to FIG. 2 there is illustrated two sintered metal
pre-fabricated sections 30 and 32 which when sintered together form
the rocker arm body 22. Rocker arm section 32 incorporates
lubricant pathway grooves 34 and 36 which when the two sections 30
and 32 are combined, i.e. covered by surfaces 44 and 46 during
assembly, form oil passages which communicate lubricating oil
provided by the rocker shaft (not shown) installed in openings 38.
The pre-formed lubricant pathways 34 and 36 may follow any desired
path. The circuitous path of the groove 34 is facilitated by means
of the two rocker arm sections which further permits openings 48,
50, and 52 which reduce mass and rotational inertia and permits
structural beam element 42 which increases the stiffness of the
rocker arm body shown in FIG. 3.
[0011] Although the invention has been described with respect to a
preferred specific embodiment, many variations and modifications
will become apparent to those skilled in the art. It is therefore
the intention that the claims be interpreted as broadly as possible
in view of the prior art to include all such variations and
modifications.
* * * * *