U.S. patent application number 10/570104 was filed with the patent office on 2006-12-14 for piston for an internal combustion engine.
Invention is credited to Rainer Scharp.
Application Number | 20060278180 10/570104 |
Document ID | / |
Family ID | 34258322 |
Filed Date | 2006-12-14 |
United States Patent
Application |
20060278180 |
Kind Code |
A1 |
Scharp; Rainer |
December 14, 2006 |
Piston for an internal combustion engine
Abstract
The invention relates to a piston for an internal combustion
engine, comprising an essentially cylindrical basis member made of
forged aluminum and a ring element that is disposed in the radially
outer edge area of the bottom of the piston and forms an annular
cooling channel along with the basic member. The ring element is
made of cast aluminum and is provided with a ring support for a
compression ring, said ring support being made of Ni-resist.
Inventors: |
Scharp; Rainer; (Vaihingen,
DE) |
Correspondence
Address: |
WILLIAM COLLARD;COLLARD & ROE, P.C.
1077 NORTHERN BOULEVARD
ROSLYN
NY
11576
US
|
Family ID: |
34258322 |
Appl. No.: |
10/570104 |
Filed: |
September 1, 2004 |
PCT Filed: |
September 1, 2004 |
PCT NO: |
PCT/DE04/01938 |
371 Date: |
April 3, 2006 |
Current U.S.
Class: |
123/41.35 |
Current CPC
Class: |
F02F 3/0023 20130101;
F02F 3/22 20130101; F02F 3/003 20130101; F16J 1/09 20130101; F16J
1/005 20130101 |
Class at
Publication: |
123/041.35 |
International
Class: |
F01P 3/10 20060101
F01P003/10 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 2, 2003 |
DE |
103402926 |
Claims
1. Piston (1) for an internal combustion engine, having an
essentially cylindrical, forged basic body (4) made of aluminum,
whose one face forms a piston head (5), having pin bosses (8) with
pin bores (3) disposed on the underside of the basic body (4) that
faces away from the piston head (5), having skirt elements (9) that
connect the pin bosses (8) with one another, having a ring element
(6) disposed in the radially outer edge region of the piston head
(5), which forms a ring-shaped cooling channel (22) with the basic
body (4), wherein the ring element (6) consists of cast aluminum
and has a ring insert (11) for a compression ring, that the ring
element (6) is connected with the basic body (4) by way of a screw
connection that consists of an inside thread (19) disposed on a
side of the ring element (6) that lies radially inside, and an
outside thread (18) that matches the former, disposed in the region
of the mantle surface (13) of the basic body (4) on the piston head
side, and that the end of the screw connection (18, 19) on the
piston head side is sealed by means of a weld seam (4).
2. Piston (1) for an internal combustion engine according to claim
1, wherein the ring insert (11) consists of Ni resist.
Description
[0001] The invention relates to a piston for an internal combustion
engine, in accordance with the preamble of the claim.
[0002] A piston for an internal combustion engine, having a basic
body made of aluminum and a ring element disposed in a radially
outer edge region of the piston head, which ring element forms a
ring-shaped cooling channel with the basic body, is known from U.S.
Pat. No. 2,772,933. The ring element consists of an iron alloy,
which brings the disadvantage with it that the ring element makes a
significant contribution to increasing the piston weight.
[0003] It is the task of the invention to avoid this disadvantage.
This task is accomplished with the characteristics that stand in
the characterizing part of the main claim. A practical embodiment
of the invention is the object of the dependent claim.
[0004] The ring element which, according to the invention, consists
of aluminum, having a ring insert consisting of Ni resist, for a
compression ring, combines the advantage of reducing the piston
weight with the advantage of offering a wear-resistant bearing for
the compression ring, and thereby increasing the ability of the
piston to withstand stress, and its useful lifetime.
[0005] An exemplary embodiment of the invention is described below,
using the drawings. These show:
[0006] FIG. 1 a piston for an internal combustion engine, having an
aluminum ring element according to the invention, in a sectional
drawing consisting of two halves, which drawing shows two
longitudinal sections of the piston, offset by 90.degree., and
[0007] FIG. 2 an enlarged representation of the section through the
edge region of the piston head having the ring element.
[0008] FIG. 1 shows a piston 1 for an internal combustion engine,
in a sectional representation that consists of two halves, of which
the left half shows a section of the piston 1 along a longitudinal
axis 2 of a pin bore 3, and the right half shows a section through
the piston 1 that is offset by 90.degree. relative to the left
half.
[0009] The piston 1 consists of an essentially cylindrical basic
body 4, the one face of which forms the piston head 5. A ring
element 6 is disposed in the radially outer region of the piston
head 5. A combustion chamber 7 is molded into the central region of
the piston head 5. Furthermore, the basic body 4 has pin bosses 8
for the pin bores 3 and skirt elements 9 that connect the pin
bosses 8 with one another, on its underside that faces away from
the piston head 5. The ring element 6 has a ring insert 11 for a
compression ring, not shown in the drawing, on its radially outer
mantle surface 10, and a second ring groove 12 below this. Below
the second ring groove 12, an oil ring groove 14 is disposed in the
mantle surface 13 of the basic body 4.
[0010] The ring element 6 is attached on the basic body 4 by way of
a screw connection, in which the ring element 6 is screwed onto an
outside thread 18 by way of an inside thread 19, which is situated
on the radially inner side of the ring element 6, which outside
thread is disposed on an axially oriented region 23 of the mantle
surface 13, which is adjacent to the piston head 5 and is set back
in the direction of the longitudinal axis 17 of the piston.
[0011] The radially inner side of the ring element 6 has a recess
20 on its lower end that faces away from the piston head 5, which
recess forms a ring-shaped cooling channel 22 with a recess 21 that
is molded into the lower end of the set-back mantle region 23 on
the piston head side. Cooling oil is passed into the cooling
channel 22 and back out of the cooling channel 22 by way of
channels not shown in the figure.
[0012] In order to prevent combustion gases, which are under high
pressure, from getting into the cooling channel 22 and into the
interior of the piston by means of the screw connection 18, 19, the
end of the screw connection 18, 19 that is on the piston head side
is sealed by means of a weld seam 24, which can be produced, for
example, using the electron beam welding method.
[0013] The piston 1 that consists of the basic body 4 and the ring
element 6 is produced from aluminum, whereby the basic body 4 is
given the desired shape by means of forging, whereas the ring
element 6 is produced using a casting method. In this connection,
the ring insert 11, which consists of Ni resist (austenitic cast
iron with components of Ni, Mn, Cu, and Cr), is cast into the ring
element 6. After the ring element 6 has been screwed onto the basic
body 4, and the screw connection 18, 19 has been sealed by means of
the weld seam 24, the piston 1 is given its final shape by means of
a cutting production process, for example by means of lathing.
[0014] The section through the edge region of the piston 1 on the
piston head side, shown in FIG. 2, shows the ring element 6 having
the cast-in ring insert 11, which is connected with the basic body
4 by way of the screw connection that consists of inside thread 19
and outside thread 18. The weld seam 24 that serves to seal the
screw connection 18, 19 can be clearly seen.
REFERENCE SYMBOLS
[0015] 1 piston [0016] 2 longitudinal axis [0017] 3 pin bore [0018]
4 basic body [0019] 5 piston head [0020] 6 ring element [0021] 7
combustion chamber [0022] 8 pin boss [0023] 9 skirt element [0024]
10 mantle surface [0025] 11 ring insert [0026] 12 second ring
groove [0027] 13 mantle surface [0028] 14 oil ring groove [0029] 17
longitudinal axis of piston [0030] 18 outside thread [0031] 19
inside thread [0032] 20 recess [0033] 21 recess [0034] 22 cooling
channel [0035] 23 region of the mantle surface of the basic body 4
[0036] 24 weld seam
* * * * *