Note: Descriptions are shown in the official language in which they were submitted.
~L~9~3~
The present invention relates to a valve device,
especially for die casting machines, and has a control drive
and a control member to adjustably limi-t the opening of the valve
cone; the control member is arranged between the control drive
and the valve cone, and engages in a thread of the valve housing.
German Gebrauchsmuster 76 04 336 discloses a valve
device, for example for heating units, cooling units, or the
like, which has a valve stem which carries out a stroke
movement. The valve stem can be actuated by an adjusting
drive fastened to -the valve, with the adjusting drive being a
standard loader, and with a transmission being arranged between
the drive shaft of the motor and the valve stem for converting
the torque into a stroke movement. German Offenlegungsschrift
20 58 112 further discloses a device for controlling the
connection of the multiplier of press plungers of multiplier
die casting machines. With this device, the opening movement
of a closure piston is adjustable by a handwheel which acts
on a longitudinal spindle. When the handwheel is turned,
with the aid of the spindle, a longitudinal displacement of
the spindle, and thereby an adjustment of the opening displace-
ment of the valve cone, is effected. Thus German Offenlegungs-
schrift 20 58 112 and German Gebrauchsmuster 7 507 127 disclose
valve de~ices in which the valve cone is adjustable by a
control member which engages in a thread of the valve housing
or of a part of the valve housing.
In contrast to these heretofore known devices, it
is an object of the present invention to provide a quick
acting valve device with which the adjustable opening limitation
of the valve cone can be effected with the aid of small manual
or motor forces with structurally simple means in a space
saving device housing in the direct drive.
According to the present invention there is provided
a valve device comprising a valve housing having an internal
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:~iL9;~3'~5
thread; a valve cone arranged in the valve housing in such a
way as to be axially displaceable -therein, the valve cone having
working surfaces which are adap-ted to be acted upon by hydraulic
pressure; a control drive associated with the housing; and a
control member in the form of a threaded sleeve, the threaded
sleeve being arranged in the housing between the valve cone
and the control drive, to which it is operatively connected;
the threaded sleeve and the control drive serving to adjustably
limit the displacement of the valve cone; the threaded sleeve
having an external thread which engages in the internal thread
of the housing; the threaded sleeve having a first end face which
faces the valve cone and projects into a first valve chamber;
the threaded sleeve also having an opposite second end face
which is directed away from the valve cone and projects into a
second valve chamber; every time pressure acts on the working
surfaces of the valve cone, different hydraulic pressures are
exerted on the opposite end faces of the threaded sleeve for
releasing the sides of the thread of -the sleeve from the sides
of the thread of the housing.
According to another aspec-t of the invention there
is provided a valve arrangement comprising a valve housing;
the valve housing having an interior space, a fluid inlet port
for admitting fluid under pressure, a fluid outlet port for
directing fluid under pressure out of the housing, a valve
seat arranged between inlet port and outlet port, a drain port,
a control port for admitting control pressure fluid to a control
chamber and a stationary thread located in the interior space
and having opposed flanks of thread, a main valve in the interior
space, ~he main valve having a valve member adapted to cooperate
with the valve seatl a stroke-limi-ting stop means, the valve
member taking a first end position when engaged on the valve
seat, and a second end position when engaged by the stroke-
limiting stop means, a control piston connected to the valve
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member and movable in the control chamber to control the end posi-
tions of the valve member, a drive mechanism, -the drive mechanism
including the s-tationary thread, furthermore an adjustable threaded
bushing connected to the stroke-limiting stop means and meshing
with the stationary thread, the threaded bushiny separating a control
fluid admission space from the control chamber in the interior
space, and a rotary driving means connected to the threaded
bushing to rotate and adjust same in the interior space, a control
valve device, the control valve device being connected to the
control port and being adapted to produce a first control pressure
sufficient to move the control piston and the valve member onto
the valve seat, and a second control pressure w.hich is low enough
so that the control piston is moved by the fluid pressure onto -the
stroke-limiting stop means, and a pressure differential means, the
pressure differential means being arranged between the control
fluid admission space and the control chamber so that when the
first control pressure is admitted to the fluid admission space,
the threaded bushing is shifted in one direction between the
limits of the opposed flanks of the stationary thread and when
the second control pressure is admitted to the control chamber and
the control piston is moved against the stroke-limiting stop means,
and the threaded bushing is shifted in the other direction between
the limits of the opposed flanks of the stationary -thread.
The following is a description by way of example
of certain embodiments of the present invention, reference
being had to the accompanying drawings in which:
Figure 1 showsone embodiment of the inventive device
wi-th a first type of control;
Figure 2 shows another embodiment of the inventive
device with a displacement pickup for the electrical control
circuit and with a second type of con-trol or regulator; and
Figures 3a-c show connection~ between -the threaded
sleeve and the shaft of the control drive.
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Referring now to the drawings in de~ail, the overall valve
mechanism of the inventi~e device is embodied as a cylindrical
cartridge and for~s an interchangeable structural unit with the
individual valve parts which are to be described subsequently.
e bore 2 of ~he housing 1 communicates for instance with a non~
illustrated feed or supply line of ~ pres~ure reservoir of
die casting machine9 wh.ile the axial bore 3 of the housing 1
COTMnUnicates with -the cylinder charnbar. The bores 2 ~d 3 ~an
also serve other purposes. The inner end of the ~ore 3 farrns
the annular valve seat 4~ ~hen the valve is closed, the recessed
head surfac~ 5 of the valve corle 6 rests against this valve
seat 4. The arrangement and c~structîon of the valve seat 4
~nd ~e recessed head surface S is such 'Lhat when ~he valve
is closed, the pressure in the line 2 and in the annular chamber
2a acts o~ the projected diame~ral surface of the portion 5a of
the head surface 5.
At the same height a~ the bore 2, the housing 1 has a fur~
ther bore 7 which5 in front of the bore 3, can also be closed
off by the valve cone 60 The val~e c~le 6 has a hollow cyli~-
2û drical shape, and its outer wall is guided on a portion 8 ofthe longi~udinal bore 9 of ~he housing 1. l~e back end of
the valve c~ne 6 has an annular thickened portion 10 ~ich is
direc~ed radially outwardly, ~he bore 9 has a corresporldixlg
w;dened portion 11~ In this wa~, on the one hand an c~nular
shoulder 12 is formed on the housing 1 and an annular shoulder
13 is formed on the valve cone 60 AI1 annular chamber results
between ~he shoulders 12 and 13 in lthe widened por~ion 11 o~
the bore 9O This a~nular chamber is kep~ free of pressure
via the bore 14. At the same time " the back thic~ened portion
30 10 increases the effectiYe bas~k erad face of the valve cone 6
relativ~ to the eff~ctive fr~rlt end face thereofO The inner
wall OLC the hollow val~e cone 5 similarly i~orms a shoulder 15"
which forms one abutment of a spring 16 whlch wil:L subse~
~ ~9 Z 3~7
quently be described in detail~
The widened portion ll of the bore 9 merges into ~ valve
chamber 17, into which opens a bore 18 which co~mmicates
with a bore 21 via a ~irst check valve 19 and a second op-
positely directed check v~lve 20. The bore 21 in turn com-
munica~es wi~h a further chamber 24 via ~he bores 22~ 23
The head 25 of a threaded sleeve or bushing 26 is dis~
placeably and sealingly arranged în the wldened por~ion o
of thP bore 9. The end face 27 (Fig, 2) of the head 25~ as
well as the back end face 28 of ~he valve cone 6, are bo~h
under ~he ef~ect of the pressure in the chamber 17 and in the
bore 18. The ex~ernal threads of the threaded sleeve 26 en
gage in the internal threads 29 of the valve hou~ing l~ The
bark end face 3Q of the threaded sleeve 26 ~Fig~ 2~ is under
the effect of the pressure in the chamber 31; ~h~s pressure
is also present in ~he bore 21 as well as9 via the bores
22, 23~ in the chamber 249 which is axially delimited by
the shoulder 32 o the housing 1 and ~he shoulder 33 of ~he
threaded sleeve 26. The second end of ~he axial ~ompression
20 spring 16 re~ts against the end face 27 of the threaded
sleeve 26. Ihe sprlng 16 may also be provided wi~h an axial
ab~tmen~ or thrus~ bearing for reducing the fric~ional ~urn~
ing for¢esO
The adjusting or control drive for the threaded ~leeve
26 i~ designa~ed generally by ~he reference nurneral 35. The
shaft 34 of the control drive 35 is mounted in the ~al~e
housiD~ 1. In this connec~îon~ ~he shaft 34 is connec~ed
with ~he dri~ sha~t 37 of the control drive 35 by me~ns o
a clutch or coupling m~nber 360 The ~o}ltrol drive 35~
3~ which may, for example, be a s-t:epping motor having a small
torque, is arr~ged in the housing 38~ The fron~ end of
the shaft 34 sealingly projecll;~ in~o the inner cha~iber 39
o: the valsre cone 6, ~d i~ surrounded by ~he spring 160
~ ~g ~ 3~ 5
The threaded sleeve 26 is also sealed off relative to the
shaft 34, with which i~ îs non-rotatably connected. Ac-
cording to FigO3a, this ~onnection of the threaded sleeve
26 with ~he shaft; 34 i5 effected by a plurality o axial
ballraces 40~ According to Figo 3b, the non; rotatable con-
nec~io~ be~ween khe parts 26 and 34 can be e~fected
by a pin 41 which engages in a corresponding groove 42.
Finally~ according ~o Fi~. 3c, the non-rota~abili~y of ~he
threaded sleeve 26 relative to the shaft 34 is accomplished
10 by keyes 43 arld grooves 44.
The inner ch~ er 39 of the valve cone 6, and t~e inner
chamber of the shaft 349 are kept free of pressure by means
of a bore 45 (Figo 2)o I~ addition to resting on th~ wall of
the bore 9 and o the widened portion 11, the guidance of
the valve cone 6 is efec~ed by an ax~al rod 46 which is
guided within the ~haft 34.
In Figo 2 ~ this axial rod 46 passes through the shaft 37
of t~e control drive 35 and ends in a displacement pick-
up 47 by means of whlch a position control re~ulation of the
~alve cone 6 of the valve control 9 w~ich is to be described
below; can be effected~
The ~hreaded sleeve 269 and especially its ~hreads 29 and
the counter~hreads 48 (Figo 2) Of the housing 19 are ;mportant
to the present invention. In this connect-Lo~g ~he chec~ valve
19 acts as a differential pressure valve between the chamber
17 in front of (i.e O let in F;gs. 1 and 2) the threaded sleeve
26) and the chamber 31 behind (i~ e. to th~ right of ) th~
~hreaded sleeve 26~ ~hen pressure is imparted in the ~ore 21,
~his pressure results in the chamber 31~ w~ile a lower pres-
sure is present .~n the cha~ber 17 due to the check val~e 199as a resul~ the threaded sleeve 26 i~ pressed to the left
in Figs~ 1 and 2~ wit~ thP sides of the ~hreads 29 of ~he
sleeve 26 bei~g lifted from the sides of the threads 48
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against the action of the spring 16, and with these sid~s be~
ing repeatedly provided with a lubricating film~ To shift the
sleeve 26, as a resulk of which the stroke of the valve cone 6
can be changed9 only small forces are therefore necessary on
the shaft 349 since the only forces to be overcorne ~re the
frictional forces betw~en the t~reads 29 and 48 and the seals,
~nd the spring forces 16, 19, and 200 A s-kicking or sPizing
of the t.hr ad sid~s against one ano~her is rendered impossible
by repea.ting the aforem ntioned process after each time the
thread sides are acted upon wi~h pressure.
Since the end face 28 of the seco~d portlon 10 together
with the shoulder surface 15 ~orm a greater surface than do
~he projected surfaces of the por~ions 5a and 5b (Fig. 1~,
this results in thæ necessary differential pressure effect
fvr the closing process of the valve cone 6
In order to assure the pressure dif~erential betw~en th~
chamber 17 vrl the one hand and the chamber 24 and 31 on the
other hand9 ~he widened head 25 of the sleeve 26 is provlded
with two seals 25a and 25b, which can be embodied as circum~
20 ferential or gap sPals~
The circuit diagram of Fig. 1 providas a check valve 50
wh~ch is co~nected with the bore 7 in the form of a control
pressure relief valve9 so that the valve cone 6 rema1ns closed
even i the principal pre~sure in the bore 2 suddenly escapes~
An electrically act uated path sea~ing valve 51 w~ich is free
of leak oil is c~nnected to the valv~ 50 as a preliminary
control sta~e for the sudden opening of the valve cone 6
A :Elow regula~ing valve 52 is provi~led for ~he lîmited con~
trol oil supply for the slow opening arid olosing rnovements of
30 the valve corle 60 The flow regulatirlg valve 52 i5 eon~ected
with a che~k val~e 53 ~Jhich ser~res ~o separa~e ~he on~rol
oil flow be~ween the pa~h seating valve 51 and the main
trol valve 54" When the main control v11~re 54 is acttlate~
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by the pilot valve 51~ a sudden opening movement of the valve
cone 6 is effected. An elPctrically actuated path seating
valve 55 which is free of leak oil is connected wLth the out-
put 62 of the mai~ control valve 54. A flow control valve 56
for mamlal preselection o~ the slow opening movemen~ of khe
val~e cone 6 is connec ed ahead of ~he path seati~gualve 55,
and is connected with the bore 21 of ~he housing 1.
Operation during slow opening of ~he valve cone 6 takes
place as follows:
When the path seating val~e 55 is actuated, more control
oil can flow ou~ through the bore 21 and the flow control
val~e 56 over ~he line 60 ~han can flQW through the check
valve 50, ~he path seating valve 519 the 10w regulating
valve 5~ and the check valve 53. As a result, a pressure
drop is achieved in thP bore 21 and in the chamber 17 by
means o~ the check valv~ 20. Thîs pressure drop effects
movement o the valve cone 6 in the dîrection of opening
due to the higher pressure on the portion 5a. When the
pre~sure is reversed, a closing of the valve cone 6 is
20 e :fected .
Rapid open;ng o the valve cone 6 can succeed the
slow opening process at any ~ime. If for this purpose
the path sea~ing valve 51 is activated and the previously
closed main control valve 54 is opened, the control 10w
escapes from thP chamber 17 through the check valve 20~
the bore 21, the line 61, and the open main con~rol ~alve
54 and the outlet 62 with a larger escape cross sec~i on
than t~t of the flow control valve 569
In the embodiment according ~o Fig~ 2 9 ~he arrange~
30 ment of the circuit diagram is the same as in Fig~ ly
except that the free end of ~he axial rod 46 acts as a
control lug on an ele~rical displacement pickup 47~
The ~low control ~alve 56 and ~he pa~h ~ea~ing valve
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55 are replaced by an electrical, proportionally adjustable
unit having posit:ion control,. In this way it is possible to
regulate the slow openîng and closing of the valve cone 6 as
desired; in other words, it is possible to achieve a rated-
ac-~ual-value agreement of the valve cone 6 via the displace-
ment pickup 470
The rapid opening of the main control valve 54 is ef-
fected in the mamler prevlously described.
Although the pa~h seating valves Sl and 55 are described
as being activa~ed electrically7 it would also b~ possible to
actuate them pneumatically or hydra~lically.
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