U.S. patent application number 12/664450 was filed with the patent office on 2010-06-03 for applicator for applying fluid to a substrate, comprising valve mechanisms, method for cleaning said applicator, and valve mechanisms for said applicator.
This patent application is currently assigned to J. Zimmer Maschinenbau Gesellschaft m.b.H.. Invention is credited to Johann Achrainer.
Application Number | 20100132612 12/664450 |
Document ID | / |
Family ID | 38713602 |
Filed Date | 2010-06-03 |
United States Patent
Application |
20100132612 |
Kind Code |
A1 |
Achrainer; Johann |
June 3, 2010 |
APPLICATOR FOR APPLYING FLUID TO A SUBSTRATE, COMPRISING VALVE
MECHANISMS, METHOD FOR CLEANING SAID APPLICATOR, AND VALVE
MECHANISMS FOR SAID APPLICATOR
Abstract
Disclosed is an applicator (1) for applying fluid to a
substrate, comprising valve mechanisms (21) which are arranged in a
row and are each equipped with an application valve nozzle (31),
and a distributing fluid chamber (11) that has a fluid intake duct
(110). A cleaning valve mechanism (21) which is incorporated into
the row of application valve mechanisms (21) and is fitted with a
cleaning valve nozzle (30) is associated with the fluid intake duct
(110). A flow path (100) for cleaning the fluid chamber (11) is
formed between the fluid intake duct (110) and the cleaning valve
mechanism (20) in the distributing fluid chamber (11), said flow
path (100) being effective when the cleaning valve nozzle (30) is
open. Also disclosed is a method for cleaning said applicator (1).
In said method, pressurized cleaning fluid is applied to the
distributing fluid chamber (11), the application valve mechanisms
(21) are kept closed while the cleaning valve nozzle (30) is
opened, and the cleaning valve nozzle (30) is then closed while the
application valve mechanisms are opened when the pressurized
cleaning fluid is applied to the distributing fluid chamber (11). A
valve mechanism (2) of the applicator (1) encompasses a detachably
mounted nozzle diaphragm (3, 4) which unblocks a valve piston (51)
in the removed state. The valve mechanism (2) further encompasses a
straight fluid duct that remains free of flow corners. A setting
piston (61) is movably mounted for adjusting and setting the stroke
of the valve piston (51).
Inventors: |
Achrainer; Johann;
(Schwoich, AT) |
Correspondence
Address: |
VENABLE LLP
P.O. BOX 34385
WASHINGTON
DC
20043-9998
US
|
Assignee: |
J. Zimmer Maschinenbau Gesellschaft
m.b.H.
Kufstein
AT
|
Family ID: |
38713602 |
Appl. No.: |
12/664450 |
Filed: |
May 20, 2008 |
PCT Filed: |
May 20, 2008 |
PCT NO: |
PCT/EP08/04122 |
371 Date: |
December 14, 2009 |
Current U.S.
Class: |
118/696 ;
118/313; 134/34 |
Current CPC
Class: |
B05B 1/3053 20130101;
B05C 5/0279 20130101; B05B 1/20 20130101; B05B 15/55 20180201; B05C
5/0225 20130101 |
Class at
Publication: |
118/696 ;
118/313; 134/34 |
International
Class: |
B05C 5/02 20060101
B05C005/02; B08B 3/00 20060101 B08B003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 14, 2007 |
EP |
07090124.4 |
Claims
1. Application device for applying fluid to a substrate, comprising
valve devices which are arranged in a row and are each equipped
with an application valve nozzle for emitting the fluid under
pressure and with associated valve actuating device for controlling
the emission of fluid by closing and opening the application valve
nozzles, and comprising a common distributing fluid chamber which
can be subjected to pressure from the fluid and which connects the
application valve devices to each other for admission of the fluid,
the distributing fluid chamber being provided with a fluid intake
duct which is arranged in such a way that the fluid which is under
pressure in the distributing fluid chamber is distributed along the
row of application valve devices to the latter, characterised in
that at least one cleaning valve device which is incorporated into
the row of application valve devices for connection to the
distributing fluid chamber and is fitted with a cleaning valve
nozzle and with associated valve actuating device for closing and
opening the cleaning valve nozzle, is associated with at least the
one fluid intake duct of the distributing fluid chamber, a flow
path which is effective when the cleaning valve nozzle is open, for
cleaning the common distributing fluid chamber, being formed in the
distributing fluid chamber between the fluid intake duct (110) and
the at least one associated cleaning valve device.
2. Application device according to claim 1, characterised in that
the fluid intake duct and the associated cleaning valve device are
provided singly, all the application valve devices of the
application device being arranged between the one fluid intake duct
and the one cleaning valve device.
3. Application device according to claim 2, characterised in that
the application device comprises five to fifteen, preferably eight
application valve devices and the one cleaning valve device.
4. Application device according to claim 1, characterised in that
the cleaning valve nozzle of the cleaning valve device has an
effective flow cross-section which is many times larger, preferably
approximately 10 times larger, than the corresponding or largest
flow cross-section of the application valve nozzles of the
application valve devices.
5. Application device according to claim 1 4, characterised in that
the valve actuating devices of the valve devices are arranged in a
row spatially between the distributing fluid chamber and the nozzle
side of the application device that comprises the valve nozzles of
the valve devices, in that each valve actuating device comprises an
electromagnet device with a valve piston movable back and forth
against a return force, in that each valve device has a valve
housing with valve nozzle and valve seat with which the associated
valve piston for opening and closing the valve nozzle cooperates,
in that each valve device is designed with a piston stop against
which the valve piston operates, the piston stop being formed by an
adjusting piston which is mounted so as to be displaceable in the
direction of the stroke for setting and adjusting the piston
stroke, and in that each valve device is provided with at least one
rectilinear fluid duct which remains free from flow corners and
which connects the distributing fluid chamber to the valve seat,
the valve piston and part of the adjusting piston together forming
a wall of the straight fluid duct, and each valve device on the
nozzle side of the application device having a mounting opening in
which the valve housing as the closure element is inserted in a
releasable connection and which, when the valve housing is removed,
exposes the valve piston for removal from the valve device and the
straight fluid duct comprising the piston wall.
6. Application device according to claim 5, characterised in that
the cleaning valve nozzle forms part of the valve housing.
7. Application device according to claim 1, characterised in that
it is formed by a module element which can be assembled with
identical module elements into an application device with nozzles
arranged in rows and columns.
8. Method for cleaning an application device according to claim 1,
characterised in that i) the distributing fluid chamber which
connects the valve devices in a row along the associated cleaning
flow path to each other, admits pressurised cleaning fluid, ii) the
application valve devices are kept closed while on the other hand
the cleaning valve nozzle of the cleaning valve device associated
with the cleaning flow path is opened, and iii) then the cleaning
valve nozzle of the cleaning valve device is closed and the
application valve devices are opened when the distributing fluid
chamber admits pressurised cleaning fluid.
9. Method according to claim 8, characterised in that in method
step iii) the application valve devices are opened by the fact that
each application valve device, which for this purpose on the nozzle
side of the application device comprising the valve nozzle has a
mounting opening closed by a detachably mounted valve housing, is
opened by removing the valve housing with valve nozzle and by
freeing the mounting opening.
10. Method according to claim 8, characterised in that the
application valve devices are cleaned by the fact that method steps
i) to iii) are carried out under the control of a program using
electronic control means, the valve nozzles being opened and closed
under the control of the valve actuating devices, and in method
step iii) the application valve devices being opened by opening the
application valve nozzles.
11. Method according to claim 10, characterised in that the
application valve nozzles are each only opened individually one
after the other, while the other application valve nozzles are kept
closed.
12. Electronic control device for an application valve device
according to claim 1, which controls the open and closed states of
the valve nozzles of the valve devices by activation of the valve
actuating devices of the valve devices, characterised in that the
electronic control comprises a control program for controlling the
execution of the following sequence of steps: i) the distributing
fluid chamber which connects the valve devices in a row along the
associated cleaning flow path to each other, admits pressurised
cleaning fluid, ii) the application valve devices are kept closed
while the cleaning valve nozzle of the cleaning valve device
associated with the cleaning flow path is opened, and iii) then the
cleaning valve nozzle of the cleaning valve device is closed and
the application valve devices are opened when the distributing
fluid chamber admits pressurized cleaning fluid.
13. Valve device of an application device for applying fluid to a
substrate according to claim 1, comprising a valve housing having a
valve seat with valve nozzle for emitting the fluid under pressure,
a supply fluid chamber which can be subjected to fluid pressure, a
valve actuating device which is formed by an electromagnetic device
with valve piston movable back and forth against a return force and
engaging in the valve seat for closing and opening the valve
nozzle, and a piston stop against which the valve piston operates,
the valve actuating device being arranged between the supply fluid
chamber and the valve housing, and the valve housing together with
the valve nozzle being detachably mounted on the nozzle side of the
valve device which has the valve nozzle, as a result of which the
valve piston is released when the valve housing is removed,
characterised in that the valve device is provided with at least
one rectilinear fluid duct that remains free from flow corners and
that, passing the valve actuating device, connects the supply fluid
chamber to the valve seat, the valve piston and part of the piston
stop together forming a wall of the straight fluid duct which is
released when the valve housing is removed, and in that the piston
stop is formed by an adjusting piston which is mounted so as to be
displaceable in the direction of the stroke for setting and
adjusting the piston stroke.
14. Valve device according to claim 13, characterised in that the
valve nozzle forms part of the valve housing.
15. Valve device according to claim 13, characterised in that the
adjusting piston and the valve piston come into contact with closed
surfaces, and between the contact faces there is provided a stroke
distance of approximately 0.5 to approximately 50 .mu.m.
16. Valve device according to claim 13, characterised in that the
valve piston and the adjusting piston are held in a common piston
chamber forming a ring-chamber duct which surrounds the valve
piston and part of the adjusting piston and which makes the
straight fluid connection between the supply fluid chamber and the
valve seat.
Description
[0001] This application is a 35 U.S.C. .sctn.371 filing of
International Patent Application No. PCT/EP2008/004122 filed May
20, 2008, which designates the United States and claims the benefit
of European Application No. 07090124.4 filed Jun. 14, 2007.
BACKGROUND OF THE INVENTION
[0002] The invention concerns an application device for applying
fluid to a substrate, comprising valve devices which are arranged
in a row and are each equipped with an application valve nozzle for
emitting the fluid under pressure and with associated valve
actuating device for controlling the emission of fluid by closing
and opening the application valve nozzles, and comprising a common
distributing fluid chamber which can be subjected to pressure from
the fluid and which connects the application valve devices to each
other for admission of the fluid, the distributing fluid chamber
being provided with a fluid intake duct which is arranged in such a
way that the fluid which is under pressure in the distributing
fluid chamber is distributed along the row of application valve
devices to the latter. The invention also relates to a method for
cleaning the application device as well as a valve device for the
application device.
[0003] An application device which is in particular equipped with
electromagnetically operated valves is concerned. The valves are
opened and closed by individual activation in order to produce an
application in dots or dashes, which can result in a
two-dimensional application, on a substrate, e.g. a flat strip of
material or a surface portion. Any liquid substance is suitable as
the application fluid, in particular dye or ink for a colour
application. Also, coating or impregnation with adhesives, coating
agents or the like can be carried out. Activation determines
applied quantities, areas of application, patterns and/or applied
symbols.
[0004] Cleaning and maintenance of the application device are
particularly important. The valve nozzles have a diameter of e.g.
only 60 to 150 micrometres. The valve nozzles and fluid paths in
the valve devices can easily be blocked by very fine particles or
minute deposits. Ordinary application devices frequently have to be
completely dismantled in order in particular to clean the
distributing fluid chamber which supplies the valve devices
jointly. Contamination occurs in particular after an initial
assembly. But breakdowns due to deposits also occur while operation
is ongoing. Also, there are special cleaning requirements if the
application substance is to be exchanged, that is, for example, a
change of colour is to be made. Conventional application devices
then usually have to be completely or largely dismantled into their
constituent parts and, after subsequent assembly, adjusted with
considerable effort using separate micrometric measuring devices.
Here, the invention is to provide a remedy.
SUMMARY OF THE INVENTION
[0005] The invention is based on the aims of improving and
simplifying the cleaning of the application device and its valve
devices. The application device and the valve device are to be
capable of being effectively and easily cleaned in a large number
of cases even without dismantling, in particular also while
retaining adjustment settings of the valve nozzles.
[0006] The aims of the invention are achieved in conjunction with
the features of the application device of the kind mentioned
hereinbefore, by the fact that at least one cleaning valve device
which is incorporated into the row of application valve devices for
connection to the distributing fluid chamber and is fitted with a
cleaning valve nozzle and with associated valve actuating device
for closing and opening the cleaning valve nozzle, is associated
with at least the one fluid intake duct of the distributing fluid
chamber, a flow path which is effective when the cleaning valve
nozzle is open, for cleaning the common distributing fluid chamber,
being formed in the distributing fluid chamber between the fluid
intake duct and the at least one associated cleaning valve
device.
[0007] The aims are achieved in a method according to the invention
for cleaning the application device according to the invention, by
the fact that (i) the distributing fluid chamber which connects the
valve devices in a row along the associated cleaning flow path to
each other, admits pressurised cleaning fluid, (ii) the application
valve devices are kept closed while on the other hand the cleaning
valve nozzle of the cleaning valve device associated with the
cleaning flow path is opened, and (iii) then the cleaning valve
nozzle of the cleaning valve device is closed and the application
valve devices are opened when the distributing fluid chamber admits
pressurised cleaning fluid.
[0008] Advantageously, a valve device of an application device
according to the invention for applying fluid to a substrate, in
particular in a plurality for arrangement in a row in the
application device, comprises a valve housing having a valve seat
with valve nozzle for emitting the fluid under pressure, a supply
fluid chamber which can be subjected to fluid pressure, a valve
actuating device which is formed by an electromagnetic device with
valve piston movable back and forth against a return force and
engaging in the valve seat for closing and opening the valve
nozzle, and a piston stop against which the valve piston operates,
the valve actuating device being arranged between the supply fluid
chamber and the valve housing, and the valve housing together with
the valve nozzle being detachably mounted on the nozzle side of the
valve device which has the valve nozzle, as a result of which the
valve piston is freed when the valve housing is removed, the valve
device being provided with at least one rectilinear fluid duct that
remains free from flow corners and that, passing the valve
actuating device, connects the supply fluid chamber to the valve
seat, the valve piston and part of the piston stop together forming
a wall of the straight fluid duct which is freed when the valve
housing is removed, and the piston stop being formed by an
adjusting piston which is mounted so as to be displaceable in the
direction of the stroke for setting and adjusting the piston
stroke.
[0009] The application device according to the invention is in
particular distinguished by the fact that the distributing fluid
chamber which supplies all the valve devices of the application
device with fluid can be cleaned easily and effectively without the
application device being opened or dismantled. The cleaning valve
device is designed according to the invention in such a way that,
when the cleaning nozzle is open and the application nozzles are
closed, the common fluid chamber is flushed by the fact that
cleaning fluid under pressure is forced at high speed and hence
entraining contaminants through the distributing fluid chamber. In
order to form the cleaning flow path through the distributing fluid
chamber, the valve nozzle of the cleaning valve device has a
relatively large nozzle cross-section. This is a nozzle
cross-section which is not suitable for fluid application. As a
result, the cleaning valve device differs crucially from the
application valve devices. In other respects, the cleaning valve
device and the application valve devices of the application device
are appropriately designed the same and matching in order to
manufacture the application device cheaply and simplify valve
control.
[0010] With the application device according to the invention, a
particularly effective cleaning method can be carried out. Thus it
is particularly advantageous if the application valve devices are
cleaned by the fact that method steps i) to iii) are carried out
under the control of a program using electronic control means, the
valve nozzles being closed and opened under the control of the
valve actuating devices, and in method step iii) the application
valve devices being opened by opening the application valve
nozzles. Preferably, the application valve devices are in each case
only opened individually one after the other, while the other
application valve nozzles are kept closed. Appropriately water is
used as the fluid for cleaning, if need be with a cleaning agent
which dissolves application substance or some other suitable
cleaning fluid.
[0011] Control of the cleaning method with controlled closing and
opening of the nozzle openings can take place in a simple manner
with an electronic processor control device designed for this
purpose, by the fact that the latter is provided with a control
program which presents the above sequence of method steps and
prepares them for execution. Such a control device can be designed
in the usual manner e.g. with a computer in conjunction with a
program representing the steps of the method.
[0012] Although it may be provided according to the invention that
several groups of valve devices which are each arranged between a
cleaning valve device and a fluid intake duct, in association
therewith, are formed in one application device, a preferred
embodiment of the invention consists in that the fluid intake duct
and the associated cleaning valve device are provided singly, all
the application valve devices of the application device being
arranged between the one fluid intake duct and the one cleaning
valve device. It was found that, in particular with such an
arrangement, a particularly effective cleaning flow path through
the distributing fluid chamber is produced if the cleaning valve
nozzle of the cleaning valve device has an effective flow
cross-section which is many times larger, preferably approximately
10 times larger, than the corresponding or largest flow
cross-section of the application valve nozzles of the application
valve devices.
[0013] An application device according to the invention which is
particularly preferred in practice, in particular for colour
application, comprises the one cleaning valve device and eight
application valve devices. But also devices with fewer application
nozzles, for example with five nozzles, or with more application
nozzles, e.g. with fifteen nozzles, prove to be particularly
practical. Application units with preferably five to fifteen
application valve devices and the one cleaning valve device are
appropriately also designed as a module element which is assembled
with identical module elements into an application device with
nozzles arranged in rows and columns. Such application module
elements can be assembled with socket connections and/or screw
connections.
[0014] An application device according to the invention is in a
preferred embodiment designed with electromagnetically operated
valve devices. In conjunction with the arrangement of the cleaning
valve device according to the invention, particular advantages can
be obtained.
[0015] The electromagnetic embodiment of the application device
according to the invention consists in that the valve actuating
devices of the valve devices are arranged in a row spatially
between the distributing fluid chamber and the nozzle side of the
application device that comprises the valve nozzles of the valve
devices, in that each valve actuating device comprises an
electromagnet device with a valve piston movable back and forth
against a return force, in that each valve device has a valve
housing with valve nozzle and valve seat with which the associated
valve piston for closing and opening the valve nozzle cooperates,
in that each valve device is designed with a piston stop against
which the valve piston operates, the piston stop being formed by an
adjusting piston which is mounted so as to be displaceable in the
direction of the stroke for setting and adjusting the piston
stroke, and in that each valve device is provided with at least one
rectilinear fluid duct which remains free from flow corners and
which connects the common fluid chamber to the valve seat, the
valve piston and part of the adjusting piston together forming a
wall of the straight fluid duct, and each valve device on the
nozzle side of the application device having a mounting opening in
which the valve housing as the closure element is inserted in a
releasable connection and which, when the valve housing is removed,
frees the valve piston for removal from the valve device and the
straight fluid duct comprising the piston wall.
[0016] The above application device according to the invention
equipped with electromagnetic valves, in conjunction with the
cleaning valve device provided according to the invention and the
cleaning flow path obtained as a result, also offers advantages for
cleaning the valve fluid ducts between the distributing fluid
chamber and the application valve nozzles. Thus according to the
invention it is important that first of all cleaning of the
distributing fluid chamber is carried out by fluid flow at high
speed, and therefore from the supply fluid duct to the cleaning
valve nozzle a considerable stream of cleaning fluid which entrains
contaminants is produced. As it is ensured that the common
distributing fluid chamber is first cleaned, the individual
application valve devices can now also be flushed at high pressure,
appropriately individually in succession, as described above. No
dirt can pass from the distributing fluid chamber that has already
been flushed into the valve fluid duct which is being flushed
between the distributing fluid chamber and the associated
application valve nozzle. The rectilinear valve fluid duct which
remains free from flow corners in this case ensures excellent
flushing. Flow shadows which arise in known application devices due
to undercuts, dead corners, areas with slow flow speeds or the
like, are avoided. Harmful air bubbles are avoided, because
particularly effective deaeration is achieved by the straight flow
path running on the wall of the adjusting piston and the valve
piston. With the application valve device in each case opened
individually, the cleaning fluid cleans the path between the
distributing fluid chamber and the valve seat or the valve nozzle
arranged thereon, without the application device having to be
dismantled. An important advantage here also lies in that the
adjusting position of the valve piston set with the adjusting
piston is maintained.
[0017] Appropriately, the valve nozzle forms part of the valve
housing. A nozzle orifice is formed. Only by exchanging the valve
housing for a valve nozzle with different dimensions, can different
degrees of fineness and fluid quantities (ink quantities) be
obtained for application.
[0018] A further advantage of the above embodiment lies in that,
after the distributing fluid chamber has been cleaned according to
the invention, the fluid duct between the distributing fluid
chamber and the associated application nozzle can also be cleaned
by the fact that the detachably mounted valve housing is removed in
case of major contamination. The valve housing and the valve piston
are easily removed and remounted on the nozzle side of the
application device, that is, on the lower side of the device which
forms the application side. Such partial dismounting may be
necessary if a change of fluid is to be made, e.g. a change of
colour. Unlike conventional application devices, the adjusting
pistons, i.e. adjusting devices arranged for this purpose on the
upper or rear side of the application device, are not dismounted.
This is a considerable advantage, as it is the adjusting devices
that are very sensitive to damage. The slightest damage can already
falsify adjustments within a range of a few micrometres. Flushing
of the distributing fluid chamber with the cleaning valve device
according to the invention also covers the adjusting pistons for
cleaning, without dismounting taking place on the upper/rear side
of the application device.
[0019] The valve device of an application device according to the
invention even in the single form achieves the result that, along
the straight valve duct path between the supply fluid chamber and
the valve nozzle, a straight longitudinal flow takes place. The
longitudinal construction avoids flow shadows which would otherwise
arise due to undercuts, dead corners, areas with slow flow speeds
or the like. Hence not only can the valve device, as already
described, be cleaned particularly well by flushing through. Due to
the longitudinal flow, the inner region of the electromagnet
device, namely a magnet coil which partly surrounds the adjusting
piston and the valve piston, is effectively cooled as well. This
has a favourable effect on the life of the valve device. Design and
assembly of the valve device are particularly simple.
[0020] Furthermore, the single valve device also has the advantages
which were mentioned in connection with the valve devices of the
application device. In case of particularly major blockage, the
valve housing can easily be removed. The mounting opening is so
large that the valve piston likewise can easily be taken out. Hence
the valve fluid duct or the piston chamber opens towards the nozzle
side, that is, downwards. By flushing with cleaning fluid under
pressure, the valve fluid duct and the piston chamber are flushed
through, and any particles of dirt present are flushed out
downwards. The adjusting piston and the adjusting device are not
dismounted. Adjustment settings can be made precisely even during
operation of the device, that is, during application.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Subsidiary claims are aimed at the above and other
appropriate and advantageous embodiments of the invention.
Particularly appropriate and advantageous embodiments or possible
designs of the invention are described in more detail with the aid
of the following description of the practical examples shown in the
schematic drawings. They show:
[0022] FIGS. 1A to 1D in side views or axonometric view, an
application device according to the invention with eight
application valve nozzles and one cleaning valve nozzle,
[0023] FIG. 2 a longitudinal section through an application device
according to FIGS. 1A to D,
[0024] FIG. 3 detail D of FIG. 2, and
[0025] FIG. 4 a single valve device according to the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0026] The application device according to the invention shown in
FIGS. 1A to D comprises a box-like valve body 15 which is composed
of a lower socket portion 151 and an upper cover portion 152. The
lower portion 151 is closed by a narrow elongate nozzle plate 121
which receives valve nozzles 3. The valve nozzles 3 are arranged in
a straight row on the nozzle/application side 12. On the opposite
side, the application device 1 has an electrical plug-in connection
17 and a connecting opening 16 for application fluid. In the
practical example the row of valve nozzles 3 is defined by eight
application valve nozzles 31 and one cleaning valve nozzle 30 which
closes the row of nozzles. The cleaning valve nozzle 30 is
according to the invention arranged at the end of the row of
nozzles opposite the connecting opening 16.
[0027] As can be seen from the sectional view in FIG. 2, the valve
body 15 is connected to an electronic power switching device 9.
This switching device 9 is connected by means of a frame 19 in a
plug-in connection 18 to a cap 153 of the upper portion 152. In
this connection the switching device 9 is electrically connected to
the valve body 15 directly via the plug-in connection 17, without
using a flat-strip cable connection. The electrical plug-in
connection 17 makes electrical connections, not shown, to
electromagnetic valve actuating devices 5 of the application device
1.
[0028] FIG. 2 and the detail according to FIG. 3 show the design
and structure of the application device 1 according to the
invention in an embodiment.
[0029] In the lower portion 151 are formed recesses which receive
nine valve devices 2 in a straight row next to each other. The
valve device 20 at one end of the row is a cleaning valve device
provided according to the invention, which is equipped with the
cleaning valve nozzle 30. The other eight valve devices 21 are
application valve devices of which the valve nozzles 31 emit
application fluid which is under pressure during regular
operation.
[0030] In the upper portion 152 of the valve body 15 is formed a
distributing fluid chamber 11 which can be supplied with
pressurised fluid from one side by the connecting opening 16 via a
fluid intake duct 110. The chamber is in the shape of an elongate
duct having a substantially circular cross-section, which extends
along the row of valve devices 2. The distributing fluid chamber 11
is provided with openings 73 at equal intervals on its side facing
towards the valve actuating devices 5. This involves in each case
the opening 73 of a through-bore 70 or through-hole in the lower
portion 151. The through-bore 70 opens out in a projection 154
which engages in a mounting opening 13 of the nozzle plate 121.
[0031] The lower portion 151, the nozzle plate 121 which closes the
latter at the bottom, the upper portion 152 and the cap 153 which
closes the latter at the top are appropriately joined together with
screw connections not shown in more detail. The advantage obtained
with the invention is that these parts remain in the mounted state
when the application device 1 is cleaned.
[0032] In FIGS. 1A to D can be seen a closure element 155 with
which the fluid distributing duct 111 is closed sealingly at its
end opposite the fluid intake duct 110. This closure element may if
required be used to deaerate the distributing fluid chamber 11. Due
to the measures according to the invention, however, it is not
necessary to remove this closure element 155 for cleaning the
application device 1. Even deaeration takes place only by way of
exception.
[0033] The valve devices 2, namely the cleaning valve device 20 and
the application valve devices 21, are basically designed the same
and matching. According to the invention, however, an essential
difference lies in that the cleaning valve device 20 at the end of
the row is equipped with the cleaning valve nozzle 30 which has a
substantially larger flow cross-section than the flow cross-section
of the application valve nozzle 31 of each application valve device
21. In the embodiment, the application valve nozzles 31 have the
same flow cross-section. In the embodiment, the flow cross-section
of the cleaning valve nozzle 30 is to be ten times larger than the
flow cross-section of the application valve nozzle 31.
[0034] The valve device 2 which is therefore provided nine times is
described below.
[0035] The electromagnetic valve device 2 comprises the valve
actuating device 5 arranged in the valve body 15, a valve housing 4
with the valve nozzle 3 and a valve seat 41, a valve piston 51, and
an adjusting device 6 with an adjusting piston 61 against which the
valve piston 51 operates. The valve housing 4 with the valve nozzle
3 forms a screw-in nozzle orifice.
[0036] The valve actuating device 5 is designed as an electromagnet
device with a magnet coil 50 which surrounds the through-bore 70.
From the through-bore 70, on the projection 154 the valve piston 51
protrudes downwards into a piston chamber 8. The valve piston 51
forms the electromagnet armature of the magnet coil 50 and enters
the magnet coil 50 in the through-bore 70. The valve piston 51 is
mounted centrally in the through-bore 70. Appropriately multipoint
mounting, not shown, is provided. This can be formed by three knobs
offset by 120.degree. each on the longitudinal circumference of the
valve piston 51. Thus between the longitudinal circumferential
surface of the valve piston 51 and the bore wall of the
through-bore 70 is formed an annular gap. The through-bore 70 and
the valve piston 51 appropriately have a circular
cross-section.
[0037] The rear side of the valve piston 51 which lies in the
magnet coil 50 abuts against a congruent piston stop 60 of the
adjusting piston 61. The adjusting piston 61 enters the magnet coil
50 in the through-bore 70 from the side of the distributing fluid
chamber 11. In the process, the adjusting piston 61 extends
approximately two-thirds in the magnet coil, while the valve piston
51 enters the remaining one-third. The through-bore 70 and
through-hole form a common piston chamber in which the two pistons
are held. The adjusting device 6 comprises a screw connection 63
which is formed on the wall of the distributing fluid chamber 11
that lies opposite the wall with the fluid intake openings 73.
[0038] The adjusting piston 61 has the same cross-section as the
valve piston 51, the two pistons being aligned. The adjusting
piston 61 is centred in the through-bore 70 by the screw mounting
of the screw connection 63. Thus likewise an annular gap is formed
between the longitudinal circumference of the adjusting piston 61
and the wall of the through-bore 70. The two annular gaps in the
through-bore 70 along the adjusting piston 61 and along the valve
piston 51 form a valve fluid duct 7 in the form of a ring-chamber
duct 72. The latter extends from the fluid intake opening 73 to the
outlet opening 74 at the projection 154. The ring-chamber duct 72
forms, along the two pistons 51, 61 and the through-bore 70, a
rectilinear flow path which remains free from corners and edges
forming flow shadows. In this respect, it is also important
according to the invention that the adjusting piston 61 and the
valve piston 51 come into contact with closed surfaces. Between the
contact faces in the practical example there is only a stroke
distance of approximately 0.5 .mu.m. In every case the stroke
distance with the closed end faces of the two pistons 51, 61 is
kept so small that the flow through the ring-chamber duct 72
remains smooth and undisturbed in a straight path.
[0039] The adjusting piston 61 extends far into the distributing
fluid chamber 11 at the fluid intake opening 73 of the ring-chamber
duct 72. The cross-section of the adjusting piston 61 is kept
relatively small in the flow cross-section of the distributing
fluid chamber 11, in order to obtain a large effective flow
cross-section towards the fluid intake openings 73 in the
distributing fluid chamber 11.
[0040] The valve housing 4 is designed in the form of a nozzle
orifice which is a closure member 14 easy to attach and remove. The
valve housing 4 is formed as a swivel part with an external thread
and screwed in a releasable screw connection into the associated
internally threaded mounting opening 13 in the nozzle plate 121.
The valve housing 4 ends on the outside with an edge orifice
abutting against the nozzle/application side 12. The valve nozzle 3
is embedded centrally in the valve housing 4. It is advantageously
made of ceramic and can be inserted firmly in the valve housing 4
by pressing it in.
[0041] The valve housing 4 has a frustoconical inner chamber 8
which corresponds to the projection 154, in order to receive the
latter precisely and centrally. Furthermore, the inner chamber 8 of
the valve housing 4 is designed to receive a pretensioned conical
spring 52 which forms part of the valve actuating device 5,
pressing a head closure element 54 of the valve piston 51 for
closing the valve nozzle 3 against the latter. The valve nozzle 3
on the side of the valve piston 51 is recessed with the valve seat
41 which is engaged by the valve piston 51 with the head closure
element 54. In the process, the conical spring 52 which is seated
on the valve piston 51 is held or clamped in its pretensioned state
between an annular edge of the projection 154 and an annular edge
at the head end of the valve piston 51.
[0042] As will not be described in more detail here and can be seen
from the drawings, the components of the application device 1 are
sealed off from each other at contacting form-locking surfaces in
the region of fluid-conducting chambers and ducts in the usual
manner with seals, e.g. O-rings.
[0043] In particular with reference to FIGS. 2 and 3, operation of
the cleaning valve device 20 and the performance of steps of the
method according to the invention are illustrated.
[0044] Via the fluid intake duct 110, the distributing fluid
chamber 11 admits pressurised cleaning fluid. This takes place in a
state in which all the valve devices 2 are closed. In FIGS. 2 and
3, to clarify the drawings only the cleaning valve nozzle 30 is
inserted in the nozzle plate 121. Naturally, to close all the valve
devices 2 the other valve housings 4 are likewise mounted on the
nozzle plate 121. Appropriately water, if necessary mixed with a
cleaning agent which particularly dissolves application substance,
is used as the cleaning fluid.
[0045] While the application valve devices 21 are now kept closed,
the cleaning valve nozzle 30 is opened with the associated valve
actuating device 5. The valve piston 51 is moved against the force
of the conical spring 52 over the stroke distance towards the
adjusting piston 61, so that cleaning fluid flows out of the
cleaning valve nozzle 30 under pressure. The cleaning valve nozzle
30 has, as described above, a relatively large flow cross-section.
As a result, the fluid passes from the fluid intake duct 110 at a
high flow rate along the path 100 in the distributing fluid chamber
11 through the ring-chamber duct 72 of the cleaning valve device 20
to the cleaning valve nozzle 30. Along the flow path 100, which
passes all the valve devices 2, contaminants such as particles or
deposits are removed particularly effectively from the distributing
fluid chamber 11. This involves tiny particles for which the
rectilinear ring-chamber duct 72 is not an obstacle. It is
important in this respect that, on account of the large nozzle
opening, a high flow that entrains very fine contaminants is
produced. Here it is emphasised that the flow cross-section of the
cleaning valve nozzle 30 is so large that this nozzle is not
suitable for application and is not used for this. The stroke of
the adjusting device 6 of the cleaning valve device is set so long
that the flow cross-section of the valve nozzle 30 comes into its
own.
[0046] After the distributing valve chamber 11 has been flushed in
the manner described, the cleaning valve device 20 is closed by
switching off the valve actuating device 5. The application valve
devices 21 are now successively opened by activation of the
associated valve actuating devices 5. That is to say, in succession
there is always only one of the application valve nozzles 31 open,
while the other application valve nozzles 31 are kept closed. The
distributing fluid chamber 11 is supplied with pressurised cleaning
fluid. In this way, in each case effective cleaning and flushing of
the ring-chamber duct 72 as well as of the inner chamber 8 of the
valve housing 4 which receives the conical spring 52 and includes
the application valve nozzle 30 is achieved.
[0047] The sequence of applications of cleaning fluid under
pressure as well as opening and closing the valve devices 2 that is
carried out for the cleaning method described is advantageously
performed by an electronic control device. The latter is designed
with a control program such that the sequence of steps is
predetermined and can be carried out in the manner according to the
invention. The usual electronic control means of a computer and/or
a logic circuit for application control can be used as the
electronic control device, the program steps according to the
invention being integrated in addition. An electronic control
device of this kind is not shown in the drawings. It is wired to
the electrical contacts 91 of the electronic power device 9 for a
example using a logic circuit board.
[0048] According to the cleaning method described above in the
practical example, the application device 1 is particularly
effectively flushed in particular after the initial assembly. It is
a great advantage that cleaning and flushing take place in a state
of the application device in which the adjusting devices 6 of the
application device 1 remain mounted. On the side of the application
device 1 opposite the nozzle plate 121, there is therefore no
handling by dismounting.
[0049] Only in special cases, namely if major contamination in the
valve devices is to be remedied, is the above flushing of the
distributing fluid chamber 11 by opening the cleaning valve nozzle
30 of the cleaning valve device 20 carried out according to the
invention first of all while the application valve devices 21 are
closed, and then the valve housings 4 of the application valve
devices 21 are unscrewed and reattached successively, so that at
all times only one application valve device 21 is being
cleaned.
[0050] Removal of the valve housing 4 is particularly simple. After
the valve housing 4 has been removed, the mounting opening 13
exposes the valve piston 51 and the conical spring 52, parts which,
as such, can easily be removed downwards through the mounting
opening 13. Then flushing takes place under high pressure, for
example with water or a special cleaning agent. The valve piston
51, the conical spring 52 and the valve housing 4 with its valve
nozzle 3 are cleaned individually. Furthermore, to complete
cleaning, the valve housing 4 of the cleaning valve device 20 can
also be removed and, while the application valve devices are then
closed, flushed with water. Such measures take place only in case
of exceptions where there is major contamination. In most cases the
application valve devices 21 can be cleaned particularly
effectively according to the invention without removing the valve
housings 4 (nozzle orifices).
[0051] With the cleaning methods last described too, it is of
particular importance that the adjusting devices 6 remain mounted.
Handling is necessary only on the lower side of the application
device 1.
[0052] After each of the application valve devices 21 have been
mounted again with valve piston 51, conical spring 52 and valve
housing 4, in each case the desired fine stroke between closed
position and open position of the valve piston 51 is adjusted in a
simple manner with the adjusting device 6. For this purpose the
adjusting device 6 has a micrometric fine thread 622 with adjusting
screw 621.
[0053] An application device 1 as described in the embodiment of
FIGS. 1 to 3 can also appropriately be provided as a module unit
which can be assembled with identical module units into an
application device with nozzles arranged in rows and columns.
[0054] In the embodiment described, the valve devices 2 are
accommodated and formed in parts 151 to 153 of the common valve
body 15. Naturally, the valve devices can also each be formed by a
single valve device. Such a valve device is shown in the embodiment
in FIG. 4.
[0055] The single valve device has the same parts or corresponding
parts as the valve device 2 of the application device 1 described.
In FIG. 4 this is indicated by the fact that the reference numbers
used in FIGS. 1 to 3 are used with the number 1 after the dot. A
single valve device 2.1 according to FIG. 4 can be assembled in a
plurality into an application device according to the invention. It
is then necessary, as not shown in FIG. 4, to connect supply fluid
chambers 11.1 in series by suitable sealing means, not shown.
Joining single valve devices together in this way is known in the
art. A valve device 2.1 as in FIG. 4 has the features, functions
and advantages described for the valve device 2 of the application
device 1 described above in the embodiment.
[0056] In particular the straight flow path of the ring-chamber
duct 72.1 can be cleaned easily and effectively with the nozzle
orifice which is easy to remove and fit. The nozzle orifice can be
exchanged and mounted quickly with the desired valve nozzle 3.1.
Only handling on the lower side of the valve device 2.1 takes
place. On the upper/rear side of the valve device 2.1, all parts
remain mounted. The adjustment setting can be carried out easily
and precisely in spite of the exchangeable nozzle orifice. The
straight flow path of the ring-chamber duct 72.1 has the advantage
of avoiding flow shadows in which particles are otherwise caught,
in the region of which deposits arise and/or which impair the
through-flow for example as a result of trapped air. Due to the
longitudinal flow, the inner region of the magnet coil 50.1 is
cooled very effectively.
* * * * *