Internal-combustion engines – Cooling – Internal cooling of moving parts; e.g. – hollow valves,...
Patent
1990-03-21
1991-11-19
Kamen, Noah P.
Internal-combustion engines
Cooling
Internal cooling of moving parts; e.g., hollow valves,...
123193P, F01P 104
Patent
active
050657062
DESCRIPTION:
BRIEF SUMMARY
This invention relates to a cooled plunger piston for internal combustion engines of a kind having a piston head, and a piston stem mutually separate from said piston head and pivotally conncted to said head by way of a gudgeon pin.
BACKGROUND OF THE INVENTION
In the case of such a piston which is known from U.S. Pat. No. 4,180,027, one problem is that of evenly cooling the piston head over its entire periphery. As a rule, the cooling of the piston head is more intensive in the area in which the cooling oil is injected than it is in the areas remote from the cooling oil injection point. For this reason, it is already known from JP-A 56-124650 to enlarge the cooling oil space or the piston head with increasing remoteness from the injection point. This is likewise desired in the case of the piston mentioned at the outset.
To this end, it would be necessary to enlarge the annular cooling oil space at that point where it is quite remote from the point at which the cooling oil is injected. In the case of so-called articulating pistons which are articulatingly assembled from an upper piston part and a stem part, however, this requirement cannot be readily met, since the space required for the bosses, and which has to be kept clear when the piston is mounted in its stem part, makes it impossible to enlarge the cooling oil space.
OBJECT OF THE INVENTION
The object of the invention is to find a way of improving this situation.
SUMMARY OF THE INVENTION
According to the invention there is provided a cooled plunger piston for internal combustion engines comprising
a) a piston head,
b) a piston stem mutually separate from said piston head for pivotal connection to said head by way of a gudgeon pin,
c) bosses depending from said piston head having aligned apertures for accommodating the gudgeon pin, which bosses on assembly project into the piston stem and extend in the direction of the negative pressure side of the piston to a lesser extent in the region of that end of the stem which is towards the piston head than in the region underneath and disposed in the direction of the bottom end of the stem,
d) a closed annular space defined radially outwardly by said piston head, said space being open towards the piston stem,
e) oil collection pockets formed in the upper end of the piston stem (2) which is towards the piston head and disposed at opposite positive and negative sides of the piston, which pockets at least partially cover the annular space of the piston head, and
f) an oil injection nozzle disposed in the region of said collecting pockets for introducing cooling oil through the bottom end of the stem into the annular space of the piston head,
g) said injection nozzle being so disposed that the cooling oil is only injected on one side of a diagonal plane passing through the piston stem simultaneously in the longitudinal axis of the piston and gudgeon pin,
h) the area of one of said collecting pockets of the stem in the covered region of the annular space (3) and projected onto a plane extending vertically to the longitudinal axis of the piston being in the region of the negative pressure side smaller than the area of a collecting pocket on the positive pressure side of the piston,
i) the smaller collecting pocket of the piston stem being radially larger in the areas disposed between the bosses of the piston head than in the areas directly adjacent the bosses,
j) said larger collecting pocket having, compared with the smaller collecting pocket, the greater capacity to hold cooling oil in relation to the area covering the annular space,
k) said larger collecting pocket, at its part directly opposite the bosses, being spaced from the maximum extension of the bosses in the negative pressure direction radially inwardly by a distance, said smaller collecting pocket being spaced from the maximum extension of the bosses in the positive direction radially inwardly, the spacing at the positive pressure side being at least the same size as the spacing at the negative pressure side.
BRIEF DESCRIPTION OF THE DRAWINGS
REFERENCES:
patent: 4129108 (1978-12-01), Elsbett et al.
patent: 4180027 (1979-12-01), Taylor
Kamen Noah P.
Mahle GmbH
LandOfFree
Cooled plunger piston for internal combustion engines does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cooled plunger piston for internal combustion engines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cooled plunger piston for internal combustion engines will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1362723