RELATED APPLICATIONS
This application is a continuation-in-part of Application
Serial No. 08/121,930, filed on September 15, 1993, entitled
"Solvent Recovery System for Ink Jet Printer", and which is to
issue as U.S. Pat. No. 5,532,720 on July 2, 1996.
FIELD OF THE INVENTION
The invention relates to ink jet printers and more
particularly to a solvent recovery system for controlling
discharge of solvent vapors from an ink jet printer and for
recovery of solvent vapors for reintroduction of solvent into the
ink of the ink jet printer.
BACKGROUND OF THE INVENTION
Ink jet printing is utilized in a variety of printing
applications and is particularly useful in the assembly of
magazines where customized or personalized messages, such as
address labels, need to be printed without smearing. Ink jet
printing devices of the continuous stream type commonly employ a
print head having a droplet generator with multiple nozzles from
which continuous streams of ink are emitted under pressure. The
droplets of ink are charged and deflected by an electromagnetic
field into a gutter for ink collection or alternatively to a
specific target location such as onto paper which may be
continuously transported at a relatively high speed across the
paths of the droplets. Ink is delivered to the ink jet printing
heads from an ink supply tank. The ink which is deflected by the
electromagnetic field into the gutter is drawn by a vacuum pump
through a vacuum line back into the ink supply tank. The ink
returning to the ink supply tank is entrained in air which is
vented from the ink supply tank.
The ink used in an ink jet printer commonly includes a
highly volatile solvent such as methyl ethyl ketone (MEK). The
air vented from a conventional ink supply tank includes
significant amounts of solvent vapors, and such prior art ink jet
printers discharge substantial amounts of solvent into the
atmosphere. Such solvents are expensive materials in the
printing process, and evaporation losses comprise a significant
amount of the solvent used in an ink jet printing process.
Discharge of solvents into the atmosphere is also harmful to air
quality.
In some prior art ink jet printers, the air vented from the
ink supply tank is passed through a room temperature container
wherein solvent vapors can condense and can be returned to the
ink supply tank. Such systems are effective to return only a
small quantity of solvent to the ink supply tank, and a
substantial quantity of solvent is vented as vapor to the
atmosphere.
Since solvent and ink are in the printing process, the ink
supply tank must be refilled. Although the level of ink in the
ink supply tank can be monitored by periodic visual inspections,
the ink supply tank typically includes a level indicator for
monitoring the level of ink. Additionally, the ink must be
maintained within a specific viscosity range in order to provide
satisfactory printing results. Therefore, the viscosity of ink
supplied from the ink supply tank to the print head typically is
monitored with a viscosity meter. To prevent the tank from
running empty and to maintain the ink viscosity within a desired
range, separate ink and solvent make up containers are typically
utilized. The ink and solvent make up containers are connected
to the ink supply tank by respective conduits, and each conduit
includes a respective control valve. Each of the respective ink
and solvent control valves is moveable between a closed position
and an open position wherein ink or solvent, respectively, flows
from the respective make up container and into the ink supply
tank.
If the ink in the ink supply tank falls below a
predetermined level, a control system connected to the level
indicator causes the ink control valve to open so that ink flows
from the ink make up container into the ink supply tank to
replenish the ink supply. If the viscosity of the ink rises
above a predetermined level, the control system connected to the
viscosity meter causes the solvent control valve to open so that
solvent flows from the solvent make up container into the ink
supply tank to decrease the viscosity of the ink.
Commonly, the levels of ink and solvent in the make up
containers are monitored to ensure that the make up containers do
not run empty. Although they may be monitored by periodic visual
inspection, the make up containers typically include level
indicators connected to indicator lights. The level indicators
typically include one or more sensors extending through the top
and walls of the make up containers. The make up containers
typically also include tops which are removable for ink or
solvent to be manually poured into the respective container.
When the top of the solvent make up container is opened for
filling the container, significant amounts of solvent are vented
from the container to the atmosphere. The level indicator
sensors can also be damaged when the tops are repeatedly removed
and replaced.
SUMMARY OF THE INVENTION
The invention provides a closed loop ink supply system for
an ink jet printer wherein ink and solvent supply containers are
closed to the atmosphere to prevent the escape of solvent to the
atmosphere. More particularly, the ink supply system includes a
closed ink supply tank wherein vapors discharged from the tank
are vented through a vent tube connected to a condenser provided
for cooling the vapor in the tube sufficiently that substantially
all the solvent vapor in the vented air will condense. The
condenser is positioned above the ink supply tank such that any
condensed solvent will draw or return through the vent tube to
the ink supply tank. Substantially all solvent entrained in air
vented through the tube is recovered.
The ink supply system further includes respective ink and
solvent make up containers connected to the ink supply tank
through control valves to deliver ink and solvent to the tank.
The ink and solvent make up containers are closed to the
atmosphere and are connected to either the ink supply tank
airspace or the lower end of the vent tube through a conduit such
that the make up tanks are maintained at the same pressure as the
pressure in the airspace of the tank to thereby facilitate
gravity flow of make up ink and solvent to the supply tank.
The ink supply system further includes ink and solvent
supply devices which facilitate adding ink and solvents to the
make up containers without opening the make up containers to the
atmosphere. More specifically, each of the ink and solvent
supply devices includes a respective supply container for
containing ink or solvent, a support device for supporting the
respective supply container and a conduit connecting the supply
container to the make up container such that ink or solvent,
respectively, is supplied to the respective make up container
without venting the make up container to the atmosphere. The
support device further includes a second conduit connecting the
airspaces of the supply and make up containers to vent the make
up container airspaces to the supply containers. Preferably, the
support device supports the respective supply container for
tipping movement between upright and inverted positions.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view of a liquid supply system of
the invention.
Fig. 2 is a schematic drawing of the liquid supply system
shown generally in Fig. 1.
Fig. 3 is a schematic drawing of an ink jet printer
including the liquid supply system shown in Fig. 2.
Fig. 4 is an enlarged view taken generally along line 4-4 in
Fig. 1, showing an ink supply device.
Fig. 5 is a partial sectional view taken generally along
line 5-5 in Fig. 4.
Fig. 6 is a perspective view of an alternate embodiment of
the liquid supply system.
Fig. 7 is a sectional view taken generally along line 7-7 in
Fig. 6.
Fig. 8 is a sectional view taken along line 8-8 in Fig. 7.
Fig. 9 is a perspective view of a thermoelectric cooling
module.
Fig. 10 is a schematic view of an alternate embodiment of
the thermoelectric cooling assembly.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Shown in the various figures is a liquid supply system 10
for supplying liquid containing a volatile component to a
suitably adapted apparatus. While it should be understood that
the liquid supply system 10 can be used to supply liquid
containing a volatile component to any suitably adapted
apparatus, the liquid supply system 10 shown in the figures is
particularly well suited for supplying ink to an ink jet printer
and will be described in connection with that application.
An ink jet printer connected to an ink supply system 10 is
shown schematically in Fig. 3. The ink jet printer includes an
ink supply conduit, ink charging device, a print head including a
nozzle, an ink attracting device, an ink gutter and an ink return
conduit. The ink jet printer may also include various
conventional filters (not shown) for filtering the ink, and
conventional pumps (not shown), such as vacuum pumps, for moving
the ink through the various conduits. As shown in Figs. 1 and 2,
the ink supply system 10 for supplying liquid ink, including a
volatile solvent, to the ink jet printer includes an ink supply
tank 11, ink supply conduit 12, ink return conduit 13, ink make
up container 14, solvent make up container 16, ink supply device
18 including ink supply container 19 and solvent supply device 20
including solvent supply container 21. The system 10 is
configured as a "closed loop" to minimize the escape of the
volatile solvent, such as methyl ethyl ketone, to the atmosphere.
As used herein, "closed loop" means that the tank and containers
are closed to the atmosphere to prevent or minimize the escape of
solvent to the atmosphere.
The ink supply tank 11 is closed to the atmosphere and
includes a liquid region L and airspace A. The ink supply tank
11 is connected to the ink jet printer by the ink supply conduit
12 to supply ink to the printer and the ink return conduit 13 to
return ink from the printer. When returned to the ink supply
tank 11, the ink includes air. Air entering the ink supply tank
11 through the ink return conduit 13 escapes the liquid region L
and enters the airspace A. Solvent which evaporates or otherwise
leaves the liquid region L also enters the airspace A.
Air and solvent vapors are discharged from the airspace A
through a vent tube 26. Although the vent tube 26 may be omitted
altogether or configured differently, in the illustrated
embodiment of the invention the vent tube 26 is an elongated
tubular member having opposed upper and lower end portions 28,30.
The lower end portion 30 is sealingly connected to the ink supply
tank 11. The upper end portion 28 is connected to a condenser
32. The condenser 32 includes a low temperature cooler for
cooling the air and solvent vapor from the tube 26 sufficiently
that substantially all the solvent vapor in the vented air will
condense. Although the condenser 32 could be positioned
differently, in the illustrated embodiment of the invention the
condenser 32 is positioned above the ink supply tank 11 such that
any such condensed solvent will return through the vent tube 26
to the ink supply tank 11. Substantially all solvent entrained
in air vented through the tube 26 is recovered. The condenser 32
also includes a vent 34 for venting cooled air to the atmosphere.
Preferably, the condenser 32 is an electrically powered condenser
located on the roof of the building housing the ink jet printer
and the remainder of the ink supply system 10, so that heat and
noise caused by its operation dissipate into the atmosphere.
More preferably, the condenser 32 is a Model DX 0020 VR condenser
manufactured by Technical Equipment Fabricators Inc., West
Milford, New Jersey.
In an alternate embodiment illustrated in Figs. 6-9, a
thermoelectric cooling assembly 100 is used in place of condenser
32. The thermoelectric cooling assembly 100 includes a housing
102, a heat exchanger 104, a plurality of thermoelectric cooling
nodules 106, a plurality of heatsinks 108, a fan 110, and a power
supply 112. The thermoelectric cooling assembly 100 operates to
cool the air and solvent vapor from the tube 26 such that
substantially all the solvent vapor in the vented air will
condense. Although the thermoelectric cooling assembly 100 could
be positioned differently, in the illustrated embodiment, the
assembly 100 is positioned above the ink supply tank 11 such that
any such condensed solvent will return through the heat exchanger
104 and vent tube 26 to the ink supply tank 11. Efficiencies in
excess of 90% are obtainable with this assembly (i.e,
approximately 90% or more of the solvent entrained in air vented
through the tube 26 is recovered).
The heat exchanger 104 is illustrated in Figs. 7 and 8. The
heat exchanger has a top 114, a bottom 116, and sides 118, 120,
122, 124. The heat exchanger 104 is oriented such that the
liquid flows by gravity through the heat exchanger and through
vent tube 26 to the ink supply tank 11. As previously described,
the lower end portion 30 of the vent tube 26 is connected to the
ink supply tank 11. The upper end portion 28 of vent tube 26 is
connected to the bottom 116 of the heat exchanger 104. The heat
exchanger 104 includes an internal passage 126 extending in a
tortuous path from the bottom 116 of the heat exchanger 104 to
side 118 of the heat exchanger. The internal passage 126 has a
cross section large enough to allow vapor and liquid to pass in
opposite directions. Air from vent tube 26 flows through the
internal passage 126 to an exit tube 128. The exit tube 128 is
attached to side 118 of the heat exchanger 104 and extends
through the housing 102 for venting cooled air to the atmosphere.
In this manner, air flowing through the heat exchanger 104 via
the internal passage 126 comes into contact with a high
percentage of the surface area of the sides 122 and 124 of the
heat exchanger 104.
Although other constructions are possible, in the
illustrated embodiment, the heat exchanger is made of two halves,
or plates 130. Each plate 130 has a tortuous channel machined in
one side. The two plates 130 are connected together with the
channel sides facing each other to thereby define the internal
passage 126. The plates 130 are made out of a thermally
conductive material such as copper, aluminum, or ceramic.
The thermoelectric cooling modules 106 are mounted on heat
exchanger sides 122, 124. A thermoelectric cooling module is a
semiconductor-based electronic component that functions as a
small heat pump to move heat from one region to another. As
illustrated in Fig. 9, the thermoelectric cooling modules 106 are
planar in configuration, having opposite flat faces 132, 133.
Each thermoelectric cooling module has two leads 134, 135. A DC
voltage from the power supply 112 is applied to the leads 134,
135 such that a current flows through the thermoelectric cooling
module 106. When power is applied, heat is transferred from one
face 132 of the thermoelectric cooling module 106 to the opposite
face 133. For example, the illustrated embodiment utilizes off-the-shelf
thermoelectric cooling nodules from Melcor of Trenton,
New Jersey. Cold face 132 is in contact with the heat exchanger
104 and hot face 133 is in contact with the heat sink 108.
The heat sink 108 is preferably constructed of aluminum or
the like and is of conventional design. The heat sink 108 has a
plurality of fins 136 for dissipating heat from the hot face 133
of the thermoelectric cooling module 106. Insulating material
140 is added in various areas between the heat sink 108 and the
heat exchanger 104.
The housing 102 includes a plurality of side vents 138 to
allow air to flow within the housing 102. The fan 110 is
disposed within the housing 102 so as to further dissipate the
heated air within the housing 102.
In an alternate embodiment illustrated in Fig. 10, an
improvement in the efficiency of the heat sinks 108 is obtained
with the addition of secondary heat exchangers 142. Secondary
heat exchangers 142 are constructed in a manner substantially
similar to heat exchanger 104. The secondary heat exchangers 142
include a passage through which air flows. The secondary heat
exchangers 142 are mounted on the hot side 133 of the
thermoelectric cooling modules 106. More specifically, conduit
144 connects heat exchanger 104 with the secondary heat
exchangers 142 such that air flows through heat exchanger 104, is
cooled by the thermoelectric cooling modules 106, and the cooler
air then flows through the secondary heat exchangers 142. In
this manner, the hot face 133 of the thermoelectric cooling
modules 106 is cooled. Exit tube 144 is connected to the
secondary heat exchanger to vent cool air to the atmosphere.
The ink make up container 14 and solvent make up container
16 are connected to the ink supply tank through respective ink
and solvent conduits 36,38 to deliver ink and solvent to the tank
11. Each of the respective ink and solvent conduits 36,38
includes a respective control valve 39,40 for controlling the
flow of ink or solvent from the respective make up container
14,16 into the ink supply tank 11. Each of the control valves
39,40 is moveable between a closed position and an open position
wherein ink or solvent respectively can flow into the ink supply
tank 11. The movement of the control valves 39,40 is controlled
by the control system (not shown) to which each is connected.
The control system includes a level indicator (not shown) in the
ink supply tank 11 for indicating the level of ink in the ink
supply tank 11, a viscosity meter (not shown) for indicating the
viscosity of the ink supplied from the ink supply tank 11, and
one or more control circuits (not shown) for operating the
control valves 39,40.
When the ink level in the ink supply tank 11 falls below a
predetermined level, the control system causes the ink control
valve 39 to open so that ink flows from the ink make up container
14 into the ink supply tank 11 to replenish the ink supply. If
the viscosity of the ink rises above a predetermined level, the
control system causes the solvent control valve 40 to open so
that solvent flows from the solvent make up container 16 into the
ink supply tank 11 to decrease the viscosity of the ink.
Each of the ink and solvent make up containers 14,16
includes a respective liquid region L and airspace A, and is
closed to the atmosphere by a top 41. The airspaces A of the ink
and solvent make up containers 14,16 are connected by respective
ink and solvent pressure equalizing conduits 42,44 to the lower
end portion 30 of the vent tube 26. In an alternate embodiment
of the invention, the pressure equalizing conduits 42,44 can be
connected to the airspace A of the ink supply tank 11. The
respective conduits 42,44 equalize the pressure between the ink
supply tank 11 and the ink and solvent make up containers 14,16
to thereby facilitate flow of ink and solvent from the respective
make up containers 14,16 to the ink supply tank 11. Although the
make up containers 14,16 can be positioned differently, in the
illustrated embodiment of the invention the make up containers
14,16 are positioned generally above the ink supply tank 11, so
that ink and solvent flow by gravity into the ink supply tank 11.
Although the conduits 42,44 can be configured differently, in the
illustrated embodiment of the invention each of the conduits
42,44 includes first and second portions 46,48 and a manifold 50.
The first portion 46 is connected from the respective makeup
container 14,16 to the manifold 50. The second portion 48
extends from the manifold 50 to the tube 26. In the illustrated
embodiment of the invention, the second portion 48 is a single
conduit common for both the ink and solvent make up containers
14,16, and the manifold 50 connects the first portion 46 of both
conduits 42,44 to the single second portion 48.
Although the ink and solvent make up containers 14,16 can be
constructed differently, in the illustrated embodiment of the
invention each includes a level indicator (not shown) connected
to an indicator light (not shown) to indicate if the level of ink
or solvent falls below a predetermined level. The ink and
solvent supply devices 18,20 include respective ink and solvent
support devices 52,54 and ink and solvent supply containers 19,21
to supply ink and solvent respectively to the ink and solvent
make up containers 14,16. Each of the ink and solvent supply
containers 19,21 includes a respective liquid region L and
airspace A. Although the ink and solvent supply containers 19,21
can be constructed differently, in the illustrated embodiment of
the invention each is a removable plastic bottle including a
bottom and an open neck having external male threads. When full,
a supply container 19,21 is connected to a respective support
device 52,54 as described in detail below, to supply its contents
to a respective make up container 14,16, and is removed and
replaced when empty.
The ink and solvent supply devices 18,20 include respective
support devices 52,54, for supporting the ink and solvent supply
containers 19,21 and first conduits 56,62 and second conduits
58,64 connecting the respective ink and solvent supply containers
19,21 to the respective ink and solvent make up containers 14,16.
The ink and solvent supply containers 19,21 are supported by the
respective support devices 52,54 such that ink and solvent are
supplied to the respective ink and solvent make up containers
14,16 without solvent vapors being vented from the ink and
solvent make up containers 14,16 to the atmosphere. A small
amount of solvent vapor may be vented from the make up containers
14,16 and supply containers 19,21 to the atmosphere when the
supply containers 19,21 are removed for replacement, but solvent
vapor is not vented from the make up containers 14,16 to the
atmosphere when the supply containers 19,21 are connected to the
and support devices 52,54. Although the ink and solvent supply
devices 18,20 can be positioned differently, in the illustrated
embodiment of the invention the supply devices 18,20 are
positioned generally above the make up containers 14,16, so that
ink and solvent flow by gravity into the make up containers
14,16.
The supply devices 18,20 for supporting the respective ink
and solvent supply containers 19,21 are substantially identical
and will be described in connection with the ink supply device
18. Although the supply device 18 can be constructed
differently, in the illustrated embodiment of the invention the
ink supply device 18 includes a support device 52 connected to
the first conduit 56 for connecting the ink supply container 19
to the ink make up container 14 to deliver ink from the ink
supply container 19 to the ink make up container 14. The support
device 52 is also connected to the second conduit 58 for
connecting the airspace A of the ink make up container 14 to the
airspace A of the ink supply container 19 to vent the airspace A
of the ink make up container 14 to the ink supply container 19.
Although other connections of the second conduit 58 are possible,
in the illustrated embodiment of the invention the second conduit
58 is connected to the airspace A of the ink make up container 14
at the manifold 50.
The support devices 52,54 for supporting the respective ink
and solvent supply containers 19,21 are substantially identical
and will be described in connection with the support 52 for
supporting the ink supply container 19. Referring to Figs. 4 and
5, while other configurations of the support 52 are possible, in
the illustrated embodiment of the invention the support 52
includes a generally U-shaped bracket 68 and a block 70. The U-shaped
bracket 68 includes a pair of parallel vertically
extending legs 69, and the block 70 extends horizontally between
the parallel legs 69. The block 70 includes opposed end portions
71,72 mounted on the respective legs 69 for pivotal movement
about a horizontally extending longitudinal axis between a first
position P1 and a second position P2. The support 52 supports
the ink supply container 19 for tipping movement from a first
position P1 where the ink supply container 19 is substantially
upright to a second position P2 where the ink supply container 19
is substantially inverted, and wherein in the second position P2
the ink supply container 19 supplies ink through the first
conduit 56 to the ink make up container 14 and the second conduit
58 vents the airspace A of the ink make up container 14 to the
ink supply container 19.
The block 70 further includes a plurality of outer sides 73
and a radially extending primary aperture 74 having an inner wall
76 and opposed open upper and lower end portions 78,80. When the
block occupies the first position P1, the upper end portion 78 is
generally above the lower end portion 80; however, when the block
70 is pivoted to position P2, the relative positions of the upper
and lower end portions 78,80 are reversed. The upper end portion
78 of the primary aperture 74 includes female threads for
engaging the male threads on the neck of the ink supply container
19. In the lower end portion 80, the primary aperture 74
includes another set of female threads for engaging a threaded
first connector 82. The first connector 82 connects the primary
aperture 74 to the second conduit 58 for connecting the airspace
A of the ink supply container 19 to the airspace A of the ink
make up container 14 to vent the airspace A of the ink makeup
container 14 to the ink supply container 19. The block 70
further includes secondary aperture 84 extending generally normal
to the primary aperture 74. The secondary aperture 84 includes
an inner wall 86 and opposed inner and outer end portions 88,90.
The inner end portion 88 extends normal to the outer end portion
90 and generally parallel to the primary aperture 74, and
connects to the lower end portion 80 of the primary aperture 74.
The outer end portion 90 is open to an outer side 73 and includes
female threads for engaging a second connector 92. The second
connector 92 includes male threads for engaging the secondary
aperture 84 and is also adapted to engage the first conduit 56 to
supply ink from the ink supply container 19 to the ink lake up
container 14. The block 70 further includes a tubular member 94
having an outer wall 96 and open inner and outer end portions
98,100. The inner end portion 98 of the tubular member 94
communicates with the first connector 82 and extends from the
first connector 82 through the primary aperture 74. The tubular
member 94 extends through the upper end portion 78 of the primary
aperture 74 and into the ink supply container 19. The outer end
portion 100 of the tubular member 94 ends adjacent, but spaced
slightly from, the bottom of the ink supply container 19. When
the ink supply container 19 is tipped to position P2, the outer
end portion 100 of the tubular member 94 is located in the
airspace A of the ink supply container 19, and the inner end
portion 98 communicates with the first connector 82 and second
conduit 58 to equalize pressure between the airspace A of the ink
make up container 14 and the airspace A of the ink supply
container 19, and thereby facilitate flow of the ink from the ink
supply container 19 through the second connector 92 and first
conduit 56 to the ink make up container 14.
In use, liquid ink including solvent is supplied to the ink
jet printer from the ink supply tank 11 through the ink supply
conduit 12, and unused ink is returned from the printer to the
ink supply tank 11 through ink return conduit 13. Air and
solvent leave the liquid region L and enter the airspace A of the
ink supply tank 11. Because the ink supply tank 11 is closed to
the atmosphere, the solvent vapors are not lost to the
atmosphere.
Air and solvent vapors are discharged from the airspace A of
the ink supply tank 11 through the vent tube 26. The air and
solvent vapors pass from the tube 26 into the condenser 32, which
cools the air and solvent vapor sufficiently that substantially
all the solvent vapor in the vented air condenses, while cool air
is vented to the atmosphere through the vent 34. Because the
condenser 32 is positioned above the ink supply tank 11, the
condensed solvent drains through the vent tube 26 to the ink
supply tank 11. Substantially all the solvent vented through the
tube 26 is recovered.
Alternately, the air and solvent vapors pass from the tube
26 into the thermoelectric cooling assembly 100. The
thermoelectric cooling assembly 100 operates to cool the air and
solvent vapor sufficiently that substantially all the solvent
vapor in the vented air condenses, while cool air is vented to
the atmosphere through the exit tube 128. Because the
thermoelectric cooling assembly 100 is positioned above the ink
supply tank 11, the condensed solvent drains through the vent
tube 26 to the ink supply tank 11. Substantially all the solvent
vented through the tube 26 is recovered.
Ink and solvent are delivered to the ink supply tank 11 from
the respective ink and solvent make up containers 14,16. The
flow of ink and solvent through the respective ink and solvent
conduits 36,38 is controlled by respective control valves 39,40
operating in response to the control system including the level
indicator in the ink supply tank 11 and the viscosity meter in
the ink supply conduit 12. Because the make up containers 14,16
are positioned above the ink supply tank 11, and the pressure
between the make up containers 14,16 and ink supply tank 11 is
equalized through the pressure equalizing conduits 42,44
connected to the lower end portion 30 of the vent tube 26, the
ink and solvent flow by gravity from the respective make up
containers 14,16 to the ink supply tank 11. Because the ink and
solvent make up containers 14,16 are closed to the atmosphere,
solvent is not lost to the atmosphere.
Ink and solvent are supplied to the ink and solvent make up
containers 14,16 from respective ink and solvent supply devices
18,20. The ink and solvent supply devices 18,20 include
respective ink and solvent supply containers 19,21, which in the
illustrated embodiment of the invention are removable plastic
bottles. A full bottle 19,21 of ink or solvent, respectively, is
connected to the block 70 of the respective support device 52,54
in the upright first position P1, and the block 70 is pivoted so
that the bottle 19,21 is inverted in the second position P2. The
tubular member 94 ends in the airspace A, so that the pressure is
equalized between the airspaces A of the respective make up
containers 14,16 and supply containers 19,21. Because the supply
containers 19,21 are positioned above the make up containers
14,16, and the pressure is equalized between the airspaces A, the
ink and solvent flow by gravity from the supply containers 19,21
into the respective make up containers 14,16. Because the supply
containers 19,21 are closed to the atmosphere when connected to
the respective support devices 52,54, solvent vapor is not lost
to the atmosphere.