close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2108576

код для вставки
Feb. 15, 1938.
A; BOKEMULL'ER
SCAVE'NGING TWO-STROKE ENGINE
Filed May 3, 1935
‘ 2,l».08,~576
Patented
15, 1938
‘I
I '
>
‘-
i I
UNITED sTATEs PATENT OFFICE
SCAVENGING TWO-STROKE ENGINE
‘Alfred Bokemiiller, Gaggenau, ‘ Germany, assign
or to Daimler-Benz Aktiengesellschaft, Stilt}
gart-Unterturkheim, Germany
'
Application May a, 1935, Serial No. 19,140
12 Claims. (Cl.123-65)
Two stroke combustion power engines with
continuous current scavenging have already been
proposed generating simultaneously a scavenging
current which enters radially into the cylinder,
5 proceeding in an axial way,’ and a rotary scavenging current which enters tangentially. This
offers, however, the disadvantage that the scavenging current entering radially and proceeding
in- an axial way towards the exhaust which is to
10 scavenge the inside core of the cylinder space, is
_ment of liberation of the slots e1, their continua
tion directing the scavenging current which
leaves these ports, towards the cylinder axis, at
the same time directing it ‘upwardly. As shown
in Figs. 2 and 5, the ports er and e: are arranged 5
in staggered relation to one another so that they
follow one another alternately in. the circumfer
ential direction.
,
,The exhaust outlet is provided in the cylinder
head and the out?ow of the exhaust gases is 10
too much subjected to the centrifugal effect of
controlled by means of a Poppet valve 111 asshownv '
the rotary scavenging current, getting into its
grip, whereby the scavenging of the inside core
in Fig. 1, by a rotary valve a: as shown in Fig. 2
,or?by means of a sleeve valve a: which uncovers
su?ers.
‘ports a as shown in Fig. 3.
‘
a
'
15 - The invention avoids this disadvantage, setting
?rst of all the scavenging current free, which
has a radial direction, and proceeds in an axial
way towards the exhaust and then the scaveng- ing current enters tangentially, whilst the inter-
20 ruption of the scavenging currents, especially,
The mode of Operation is as follows:
1
15
During the downstroke of the piston the upper
‘
row of ports e1 is ?rst uncovered as shown in
Fig. 1. By this means the scavenging current
or currents a: are set up which, after being de
?ected by the bottom of the piston, ?ow axially 20
proceeds in a reversed direction. By these means
a certain time is allowed for the axial scaveng-
towards the exhaust outlet, pushing the burnt ‘
gases to the ‘exhaust and towards the Cylinder
ing current to develop itself prior to the produc-
Walls with an uPW?f? directi?n 0f ?ow
_ tion of the rotary scavenging current, so that the
As soon “ as according to Fig- 2 the lower series
25 whirling gases are partly pushed towards the
of ports c: has been opened, the effect of the
5
‘ exhaust, and partly towards the cylinder walls.
lower series of slots, possessing conveniently a
The gases collecting themselves at the cylinder . largercross sectionI Prevails and a'helical Scav
walls are now taken up by the scavenging cur- engine current 11 arises- By the high Velocity of
rent starting in a rotary way, respectively prothe intake current the current receives a con‘
30 ceeding ‘ helically, and are pushed towards the
siderable centrifugal power so that the same does 30
exhaust. After interruption of the turning cur-1
rent a sturdy axial whirling current can once
not get disturbed in any way‘ by thescavenging
current entering through the upper slots 81; 0n
more be produced.
the contrary the same passes along the cylinder
‘ _
In the drawing:
35
Figs, 1 to 3 show a vertical section through the
upper part of the- cylinder of an internal combustion engine according to the invention in
three characteristic stages of the scavenging
‘
40
Process;
~
as this is admissible by the arrangement of the
Fig. 4 is across section on the'line 4-4.1n Fig.
2, and _
.
-
wall in an appropriate form, in the shape of a
sturdy edge layer 10- Hereby it can partially also ~3 5.
be put into turning movement by the spiral
'
scavenging current 1! or the same can eventually
also subsist as a partial core-current xo, so far
I
admission ports. As a rule, however, the ‘air 40
' entering at eiwill be entirely diverted-from the
Fig. 5 is a diagrammatic view on a larger scale
of'the portion of the cylinder in the region of
tangential current 1! towards the cylinder walls,
as shown by the example, ?owing in a more or
the ports.
less axial direction or in a helical line towards
'
'
45 - The admission steered by the piston takes
place, on the one side, by the admission portse1, directed radially towards the cylinder axis
and in an oblique way towards the bottomof the
piston K, and, on the other side, by the lower
50 admission ports ea, convemently directed in a.
the exhaust port.
45
When the piston is going up, another sturdy
scavenging of the cylinder core takes place, after
closing the lower slots er, the rotary scavenging
current .11 losing by its effect and the original core
currentxis developing itself anew.
q
somewhat oblique way towards the above, which
join tangentially the cylinder. The bottom of
The invention is especially designed for .Diesel
engines, respectively for air compressing ma
the piston is hereby conveniently provided with
an annular trough Kl. on the upper face of the
chines. The same can of course also be used for
mixture-compressing machines according to the
55 piston, the limitation of which forms at the mo-'
v
50
purpose of the design. Instead of the piston ,55
2,108,576
represented, a piston with a ?at surfaced bottom
can also be provided.
I claim:
.
1. In a two stroke internal combustion engine,
in combination, a cylinder having a series of
upwardly inclined tangential ports at the lower
end thereof, a piston reciprocating in the cylin
der and adapted to uncover the said ports for
admitting scavenging and charging air to the
10 cylinder so as to ?ow in a helical current around
the cylinder, said cylinder having a series of
downwardly inclined radial ports above said ?rst
mentioned ports and the piston end having de
' , ?eeting means adapted to co-operate with said
15 radial ports for guiding upwardly in the axial‘
direction of the cylinder scavenging air admitted
through the radial ports prior to the uncovering
of the tangential ports by the piston during the
downstroke of the latter and subsequent to the
rupting the ?ow of‘the ?rst-mentioned body of
air, so as to allow the ?rst-mentioned body of
air to ?ow axially through the cylinder previe
ously to and subsequently to the admission of
the helically ?owing body of air in order to en
sure thorough scavenging of the core of the
cylinder interior.
5. In a two stroke internal combustion engine, ’
in combination, a cylinder having a series of
upwardly inclined tangential ports at the lower
end thereof, a piston reciprocating in the cylin
der and adapted to uncover said ports for ad
mitting scavenging and charging air to the cylin
der so as to ?ow in a helical current around the
cylinder, said cylinder having a series of down
wardly inclined radial ports above said ?rst men
tioned ports and alternating therewith circum
ferentially and the piston end having de?ecting
means adapted ‘to co-operate with said radial
ports for guiding upwardlyin the axial direction
20 covering of the tangential ports by the piston ~ of the cylinder scavenging air admitted through
during its upstroke and an exhaust outlet at the
the radial ports prior to the uncovering of the
upper end of the cylinder.
2. In a two stroke internal combustion engine, tangential ports by the piston during the down
stroke of the latter and subsequent to the cover
in combination, a cylinder having a series of up
ing of the tangential ports by the piston during
25 wardly inclined tangential ports at the lower end‘
thereof, a piston reciprocating in the cylinder and ‘its upstroke and an exhaust outlet at the upper
adapted to uncover the said ports for admitting end of the cylinder.
6.4 In a two stroke internal combustion engine,
scavenging and charging air to the cylinder so
in combination, a cylinder having a series of
as to ?ow in a helical current around the cylin
upwardly inclined tangential ports at the lower
30. der, said cylinder having a series of downwardly _ end thereof, a piston reciprocating in the cylin
.inclined radial ports above said ?rst-mentioned
der and adapted to uncover saidports for ad
ports and the piston end having a trough there
in with the bottom thereof sloping downwardly mitting scavenging and charging air to the cylinder so as to ?ow in a helical current around the
from the periphery of the piston and then up
cylinder, said cylinder having a series of down
35 wardly towards the centre of the piston adapt
ed to cooperate with said radial ports for guiding wardly inclined radial ports above said ?rst men
upwardly in the axial direction of the cylinder tioned ports and alternating therewith circum
and the piston end having a trough
scavenging air admitted through the radial ports ferentially
prior to the uncovering of the tangential ports by therein with the bottom thereof sloping down
wardly from the periphery of the piston and then
,40 the piston during the downstroke of the latter upwardly ~ towards the centre of the piston
and subsequent to the covering of the tengential
ports by the piston during its upstroke and an
exhaust outlet at the upper end of the cylinder.
3. In a two stroke internal combustion engine,
45 in combination, a cylinder having a series of up
radial ports prior to the uncovering of the tan
stroke of the latter and subsequent to the cover
its'upstroke and an exhaust outlet at the upper
' ports and the piston end having a plurality of
depressions therein with the bottoms thereof
55 sloping downwardly from the periphery of the
piston and then upwardly towards the centre of
the piston adapted to co-operate with said radial
ports for guiding upwardly in the axial direction
of the cylinder scavenging air admitted though
the radial ports prior to the uncovering of the
tangential ports by the piston during the down
stroke of the latter and subsequent to the cover
ing of the tangential ports by the piston during
its upstroke and an exhaust outlet at the upper
'
40
45
gential ports by the piston during the down
adapted to uncover the "said ports for admitting
scavenging and charging air to the cylinder so
said cylinder having a series of downwardly in
clined radial, ports above said ?rst-mentioned
.7
adapted to co-operate with said radial ports for
guiding upwardly in the axial direction of the
cylinder scavenging air admitted through the
wardly inclined tangential ports at the lower end
thereof. a piston reciprocating in the cylinder and
50 as to ?ow in a helical current around the cylinder,
,
ing of the tangential ports by the piston during
end of the cylinder.
50
7. In a two stroke internal combustion engine,
in combination, a cylinder having a series of up
wardly inclined tangential ports at the lower end
thereof, a piston reciprocating in the cylinder
and adapted to uncover the said ports for ad
55
mitting scavenging and charging air to the cylin
der so as to ?ow in a helical current around the
cylinder, said cylinder having a series of down
wardly inclined radial ports above said ?rst
mentioned ports and having a larger cross-sec 60
tion than the tangential ports and the piston end
having de?ecting means adapted to co-operate
with said radial ports for guiding upwardly in
the axial direction of the cylinder scavenging air
admitted through the radial ports prior to the 65
65 end of the cylinder.
4. In the method of working an internal com- - uncovering of the tangential ports by the piston
bustion engine. the steps consisting in causing
a body of scavenging air to ?ow into the cylin
der and upwardly therein in the direction of the
cylinder axis towards the end of the exhaust
stroke, causing a second body of scavenging air
to ?ow tangentially into the cylinder and up
wardly therein in a helical path around the cyl
inder axis, interrupting the ?ow of the second
mentioned body of air and subsequently inter
during the downstroke of the latter and subse
quent to the covering of the tangential ports by
the piston during its upstroke and an exhaust
70
outlet at the upper end of the cylinder.
8. In a two stroke internal combustion engine,
in combination, a cylinder having a series of inlet
ports at one end thereof for admitting scaveng
ing air to the cylinder, said inlet ports being ar
ranged and directed to cause the air to ?ow in an 75
2,108,576
axial stream through the cylinder, said cylinder
having further inlet ports at the'said end of the
cylinder‘for admitting additional scavenging air to
the ‘cylinder, said further inlet ports being ar
ranged and- directed to cause the additional
scavenging 'air- to flow in a helical path through
the cylinder, an exhaust outlet at the other end
of the cylinder and controlling means forcontrol
ling the flow of- scavenging air through said
10 ports, said controlling’ means cd-Operating with
the ports so as to admit scavengingair through the
?rst-mentioned ports initially and through the
second-mentioned ports subsequently.
9. _In a two-stroke internal combustion engine,
the combination as set forth in claim 8, in which
the controlling means for controlling the flow of
scavenging air through the ports cuts off the flow
of scavenging air through the second-mentioned
ports prior to cutting oiT the flow through the
?rst-mentioned portsv
I
3
tangential inlet ports at the lower end thereof,
for admitting scavenging air to the cylinder to ?ow '
in a helical stream in the cylinder, said cylinder
having a series of radial inlet ports at the same
end of .the cylinder for admitting additional
scavenging air to the cylinder, a piston reciprocat
ing in the cylinder and adapted to co-operate
with said tangential and radial inlet ports so as
to admit scavenging air to the cylinder initially
through the radial .inlet ports and subsequently 10
through the tangential inlet ports and to out oil
the ?ow through the tangential ports prior to cut
ting o? the ?ow through the radial ports, said
piston having a de?ecting surface adapted to co
operate with the radial. inlet ports for de?ecting
the scavenging ‘air admitted through the radial
ports to ?ow in an axial stream in the cylinder,
said cylinder having exhaust outlet openings at
the upper end of the cylinder.
.
12. ~In a two stroke internal combustion engine, 20
10. In a two-stroke internal combustion engine, , in combination, a cylinder having a series of
in combination, a cylinder having a, series of tangential inlet ports in proximity to the lower
tangential inlet ports in proximity to one end end thereof for admitting scavenging air to the
thereof, for admitting scavenging air to the cylin
cylinder to ?ow in a. helical stream in the cylin
Li der to ?ow in a helical stream in the cylinder,
der, said cylinder having 'a series of radial inlet 25
said cylinder having a series of radial inlet ports _ ports in proximity to the lower end of the cylin
in proximity to the said end of the cylinder for _der located above said tangential portsv and ex
admitting additional scavenging air to the cylinder, tending at an angle situated in a plane passing
de?ecting means in the cylinder adapted to co-' i through the axis of the cylinder with respect to
operate with said radial inlet ports for de?ecting said tangential ports, so that the directional lines
the scavenging air admitted through the radial of the said ports intersect one another in the said
ports to flow in an axial stream in the cylinder plane inside the cylinder, a piston reciprocating
and controlling means co-operating _with said in the cylinder and adapted to uncover the said
tangential and radial inlet ports so as to admit inlet ports for controlling the admission- of
scavenging air initially through the radial inlet
ports and subsequently through the tangential
ports and to out 01f the ?ow through the tangen
4 _ tial ports prior to cutting off the flow through the _
radial ports,.said cylinder having exhaust outlet
40 openings at the end, of the cylinder remote from
the inlet ports.
.
11. In a two stroke internal combustion engine‘,
in combination, va cylinder having a series of
scavenging air to the cylinder, said piston having 35
de?ecting means thereon adapted to co-operate
with the radial‘ inlet ports for causing the air
admitted through the radial inlet ports to flow in
an axial stream through the cylinder and the
cylinder having anv exhaust outlet at the upper 40
end thereof.
.
.
ALFRED BOKEMULLER.
Документ
Категория
Без категории
Просмотров
0
Размер файла
477 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа