Abstract:
An ink cartridge holder for delivering ink to printing machine ink systems, includes a cover which seals the ink cartridge holder shut and allows compressed air to build up inside the holder in order to squeeze ink out of a cartridge. A locking mechanism locks the cover in the closed position and unlocks when the cover is opened. An air valve controls the delivery and extraction of air in relation to the inside of the holder, the valve being operable depending on the locked or unlocked position of the cover. A pivoting actuator independently opens and closes the cover and is contrived in such a way that, in a first phase of motion, it moves the cover into the closed position and, in a second phase of motion, locks the cover and switches the air valve, and performs an opposite operation during an opening process.

Description:
BACKGROUND OF THE INVENTION 
   The invention concerns an ink cartridge holder for delivering ink to printing machine ink systems, with a cover which seals the ink cartridge holder shut and allows compressed air to build up inside the holder in order to squeeze ink out of a cartridge, with a locking mechanism for locking the cover in the closed position and for unlocking when the cover is opened, plus a valve to control the delivery and extraction of air in relation to the inside of the holder, said valve being operable depending on the locked or unlocked position of the cover. 
   For the purpose of delivering printing ink in instances requiring only small amounts of ink it is customary to employ cartridges out of which the ink is squeezed using suitable equipment. There are various prior art squeezing devices suitable for the stated purpose, consisting, for example, of a cartridge holder which can be sealed shut by a cover. After sealing the holder, compressed air is introduced to squeeze the ink out of the cartridge through the open base of the holder. The present invention concerns a holder of this type which functions as a device for squeezing out ink. 
   DE 196 32 717 C2 discloses a pneumatic cartridge squeezing device of the above kind. The cover can be fixed in place on the tube-shaped holder by means of a bayonet lock. Inside the cover there is an air inlet through which compressed air can be introduced into the top portion of the holder below the cover. The ensuing cushion of compressed air presses down on the cartridge piston, driving it downward so that the ink is squeezed down out of the cartridge. This publication concentrates in particular on means for sealing an annular gap which may occur between the cartridge and the holder if the cartridge does not fit snugly in the holder. In the absence of further details, it may be assumed that the cover is placed on the holder by hand and that the compressed air is delivered and extracted manually. 
   DE 296 02 801 U1 also concerns a device for squeezing cartridges. Here, too, the subject is a holder which can be sealed by means of a cover. The aim is to overcome sealing problems to permit squeezing of cartridges of different formats. The operations to close the cover and control the compressed air are apparently manual. 
   EP 716 923 B1 describes another squeezing device for cartridges comprising a cylindrical holder which can be sealed by means of a flap cover to which a compressed air line can be connected. The flap cover is apparently closed and opened by hand. The process of delivering and extracting the compressed air is also manual. 
   DE 198 54 494 C2 describes another cartridge holder with a cover for sealing the latter and a valve for delivering compressed air through the cover. This document focuses primarily on operating safety. Hence the idea is to ensure that compressed air can only be delivered when the cover is properly closed, and that the cushion of compressed air is properly reduced before the cover is opened. With this in mind a valve is provided to control the air, said valve being connected to the cover via a control device so that the valve can be operated when the cartridge holder is closed with the cover. 
   All the prior art cartridge squeezing devices require a greater or lesser degree of manual intervention in order to change the cartridge. This means the printing machine has to be constantly monitored by an operator. It is not possible, even for a limited period of time, to keep ready a stock of ink greater than the volume contained in a single cartridge. 
   SUMMARY OF THE INVENTION 
   This invention is based on the task of designing an ink cartridge holder in such a way that permits substantial automation of the cartridge changing operation. 
   To solve this task a pivoting actuator is provided for independently opening and closing the cover, said actuator being contrived in such a way that, in a first phase of motion, it moves the cover into the closed position and then, in a second phase of motion, locks the cover and switches the air valve, and performs the opposite operation during the opening process. 
   The ink cartridge holder according to the invention is suitable for inclusion in a system ensuring a fully automatic supply of ink. It is possible, for example, to keep ink cartridges at the ready in a storage device and, after opening the cover of the ink cartridge holder as per the present application, to replace an empty cartridge with a full cartridge. As the opening and closing of the cover, the locking and unlocking thereof and the process of controlling the delivery and extraction of air are performed by one and the same pivoting actuator, the three processes can be co-ordinated in such a way that the required level of operating safety is achieved. Further details about this will be disclosed further on in the description. 
   The pivoting actuator preferably comprises a drive cylinder with an extending piston rod fixed to a console connected with the ink cartridge holder, on which a hinge mechanism for the cover is also mounted in a first pivot axis. 
   The hinge mechanism comprises a hinge arm with a longitudinal hole in which there is a cross bolt connected with the piston rod, which can be locked in place in the rear end position of the longitudinal hole where it remains locked until the cover closes. 
   In the first phase of motion the cross bolt is fixed immobile in the hinge arm, i.e. in the latter&#39;s longitudinal hole. With the help of the piston rod, the hinge arm can thus be pivoted via the cross bolt so that the cover moves from the open to the closed position. The cross bolt cannot be unlocked until this position is achieved, allowing it to be moved forward through the longitudinal hole without any further effect on the cover. 
   In this phase of motion, which has been designated the second phase, the movement of the cross bolt locks the cover and switches the valve. 
   In detail, this preferably happens as a result of there being, attached to the hinge arm, a bearing base which can be pivoted together with the pivot arm and on which a pivot lever is mounted in a second pivot axis contrived in the bearing base parallel to the first pivot axis. The bearing base, which is rigidly connected to the hinge arm, has a longitudinal hole into which the cross bolt also penetrates. This longitudinal hole is congruent to the longitudinal hole of the hinge arm. After the cross bolt is unlocked, it is also moved forward in the longitudinal hole of the bearing base. This movement pivots the pivot lever in relation to the bearing base. The pivot lever is connected with a cover locking mechanism on the one hand and the air control valve on the other hand. 
   The cross bolt is preferably locked by locking the pivot lever in relation to the bearing base. As the cross bolt is rigidly connected with the pivot lever this fixes the cross bolt in place so that it cannot move in either the longitudinal hole of the bearing base or in the longitudinal hole of the hinge arm. 
   The entire arrangement comprising the hinge arm and bearing base is mounted in one continuous axis, the first pivot axis, on the console. It is folded down in the forward direction when the cover is closed. The cross bolt is unlocked in that when this folding down takes place, the locking pin ensuring the locking action is pushed back by an unlocking element disposed on the console. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Preferred embodiments of the invention will be explained in more detail below with reference to the attached drawings, in which 
       FIG. 1  is a perspective view showing the cover of a cartridge holder according to the invention in the open position; 
       FIG. 2  is a similar view showing the cover during the closing operation; 
       FIG. 3  shows the cover in the closed position; 
       FIG. 4  is a perspective view of the cover showing key parts of a pivoting actuator for the cover according to the invention; 
       FIG. 5  is a perspective top plan view of key parts of the pivoting actuator for the cover; 
       FIG. 6  is a perspective, partially cutaway view of key parts of the pivoting actuator for the cover. 
   

   DETAILED DESCRIPTION 
     FIG. 1  shows a cover for an ink cartridge holder according to the invention, designated as a whole by  10 . Cover  10  is mounted with the help of a first pivot axis  12  on a console  14  so that it can be folded down to the left, out of the upright position shown, into a position in which it seals a holder which is not shown. The position of the holder is indicated by the arch-shaped edge line of a partially shown connecting plate  16 , which rigidly connects console  14  with the holder. 
   It can be seen that cover  10  has four locking jaws  18 , 20 , 22 , 24  disposed around its periphery, which grip like claws over edge elements (not shown) on the top edge of the holder (not shown), thereby holding the cover in position on the holder. This locking mechanism will be explained in more detail below. 
   The first pivot axis  12  runs across the entire width of console  14  and is mounted at both ends in bearings  26 , 28 . Located between these two bearings there is a hinge arm  30  which is rigidly connected with cover  10  through an opening in the bottom locking jaw  22 , as can be at least partially inferred from  FIG. 1 . 
   The hinge arm comprises three parallel elements separated by slots  32 , 34  into which the two fingers of a fork crown  36  penetrate ( FIG. 4 ), said fork crown being positioned at the end of a piston rod  38  of a pneumatic cylinder  40  ( FIG. 5 ) which constitutes the power source both for opening and closing the cover, for locking and unlocking the cover and for delivering and extracting air in relation to the holder. 
   Hinge arm  30  forms an integral unit with a bearing base  42 , which, like the hinge arm and parallel to the latter, starts out from a common base element  44  which can be pivoted around first pivot axis  12 . 
   Hinge arm  30  and bearing base  42  have congruent longitudinal holes  46 , 48 , through which a cross bolt  50  runs over the entire length of the arrangement comprising the hinge arm and the bearing base. 
   With the help of fork crown  36  of piston rod  38 , cross bolt  50  can, in certain circumstances, be moved crosswise to its longitudinal axis in longitudinal holes  46 , 48 , as will be explained in more detail below. 
   When cover  10  is open, piston rod  38  is in a retracted position and cross bolt  50  rests in the rear end position of longitudinal holes  46 , 48  of hinge arm  30  and bearing base  42 . In this position, the cross bolt is locked during the first phase of motion of the pivot mechanism according to the present invention. Hence the cross bolt is fixed immobile in the hinge arm  30  so that, when piston rod  38  is extended, it pivots hinge arm  30  around first pivot axis  12 , thereby folding cover  10  down into the closed position. 
   To perform the second phase of motion there is a pivot lever  52  which, in relation to bearing base  42 , is pivotably mounted in a second pivot axis  54  which runs parallel to the first pivot axis  12 . When lever  52  is pivoted, cross bolt  50  moves in the longitudinal hole  48  of bearing base  42 . Longitudinal hole  48  and hence longitudinal hole  46  as well therefore describe a circular arc around the second pivot axis  54 . 
   To lock cross bolt  50  in relation to longitudinal holes  46 , 48 , in which it is displaceably disposed crosswise to its axis, the pivot movement of pivot lever  52  in relation to bearing base  42  can be prevented.  FIGS. 1 and 6  show how this is done. 
   In the side of bearing base  42  which is folded down onto console  14  when piston rod  38  is extended, there is a window  56  in which a locking bolt  58  becomes visible, which is prestressed towards the right in  FIG. 6  by a compressing spring  60 . In the advanced position, the relatively thin tip  62  of the locking bolt penetrates through bearing base  42  into a hole  64  in pivot lever  52 . This locks pivot lever  52  in relation to bearing base  42  so that cross bolt  50  cannot move inside longitudinal hole  48 . This means that cross bolt  50  is also locked in relation to longitudinal holes  46  of hinge arm  30 . 
   On the surface of console  14  there is an unlocking block  66  with an undesignated groove with which locking bolt  58  comes into contact when bearing base  42  is folded down onto the surface of console  14 . In this region, the locking bolt has a truncated cone shaped transition surface  68 , which comes into contact with the left edge of the undesignated groove, and is thereby pushed back by unlocking block  66  towards the left in  FIG. 6  against the pressure exerted by the compressing spring  60 . This unlocks pivot lever  52  in relation to bearing base  42 . When piston rod  38  is advanced further with cross bolt  50 , the cross bolt is moved forward in longitudinal holes  46 , 48 . This has no effect on the hinge arm  30  and cover  10 . However, it does cause pivot lever  52  to be pivoted around the second pivot axis  54  clockwise in relation to  FIG. 3  or  4 . As this happens cross bolt  50  passes through longitudinal hole  48  of bearing base  42  and is at the same time moved through longitudinal hole  46  of hinge arm  30  crosswise to its longitudinal direction. The movement in these longitudinal holes does not have any effect, however, and the cover remains in its closed position. 
   Fixed to the top side of pivot lever  52  with the help of a ball joint  72  there a pull rod  70 , which is connected on the other side with the help of a further ball joint  74  with an adjusting ring  76 , which is rotatably mounted on cover  10  in a manner not shown in greater detail. In the second phase of motion of the pivoting actuator, pull rod  70  is therefore pulled to the right in  FIGS. 3 and 4 . Fixed to adjusting ring  76  there are guide bolts  78 , 80 , 82 , 84  which project vertically upwards from the adjusting ring and run in longitudinal guide holes  86 , 88 , 90 , 92  in top, inward-facing flanges  94 , 96 , 98 , 100  in locking jaws  18 , 20 , 22 , 24 . Locking jaws  18 , 20 , 22 , 24  are swivel-mounted in horizontal axes  102  ( FIG. 4 ) on the outer periphery of the cover. When adjusting ring  76  is rotated as mentioned, locking jaws  18 , 20 , 22 , 24  are clamped onto the holder and engage with counter-elements not shown here. 
   On the other hand It can be seen that when the adjusting ring is moved in the opposite direction, guide bolts  78 , 80 , 82 , 84  first move through a concentric section of longitudinal guide holes  86 , 88 , 90 , 92  before the path deflects outwards to release the locking jaws. 
   During the opening movement, the mechanism therefore initially executes an initial leg before releasing the cover. This will be commented on in more detail below. 
   When hinge arm  30  and bearing base  42  are folded forward during the first phase of motion as piston rod  38  extends, the bearing base  42 , as it comes closer to the surface of console  14 , comes into contact via a groove  104  on the underside of pivot lever  52 , with an L-shaped end of a slide  106  displaceably mounted on the surface of console  14  ( FIG. 5 ). This slide controls a three/two-way valve  110  which controls the delivery of air to the inside of the holder and the extraction of air from the inside of the holder. 
   In connection with the description of the adjusting ring it was stated that during the opening movement of the adjusting ring resp. pivot lever  52 , longitudinal guide holes  86 , 88 , 90 , 92  first have to complete a portion of the way without the cover unlocking. 
   On the other hand, when pivot lever  52  is pivoted, the movement of slide  108  starts immediately, and this movement also immediately triggers the changeover of the three/two-way valve. This means the pressure in the holder is released before the cover is unlocked. Hence there is no risk of the cover flying off suddenly, possibly causing injury. 
     FIG. 5  shows quite clearly that the pneumatic cylinder is pivotably mounted on console  14  in a pivot axis  112  with the help of two bearings  114 , 116 . Piston rod  38 , and with it fork crown  36 , can thus follow the movement of cross bolt  50  in longitudinal holes  46 , 48  and the pivot movement of hinge arm  30  without creating any tension. 
   When cross bolt  50  reaches the rear end position of longitudinal holes  46 , 48  during the retraction movement of piston rod  38 , cross bolt  50  begins to lift hinge arm  30 , and with it bearing base  42 , and the associated base part  44 . When bearing base  42  is lifted off the surface of the console, locking bolt  58  is released from unlocking block  66  so that it is pushed forward by compressing spring  60 . As this happens, the slender tip  62  of the locking bolt enters the hole  64  in pivot lever  52 . Pivot lever  52 , and with it cross bolt  50 , are locked in the rear end position of longitudinal holes  46 , 48 . 
   The functioning of the three/two-way valve  110  does not require detailed explanation. The valve features an inlet (not shown) for compressing air and an outlet to transfer the compressing air into the cartridge holder, as well as a third outlet enabling the cushion of compressed air inside the holder to be reduced to match the ambient pressure. Appropriate connections (not shown) are provided for these purposes.