RE-LOADING DEVICE FOR INK-JET WRITING HEAD
FIELD OF THE INVENTION
The invention consists of a re-loading device for ink-jet writing head, particularly suitable for re-loading a three-colour ink-jet writing head, often used in the printers that are one of the most known and widespreaded interface means.
The re-loading device is connected in a reversible manner to the body of the ink-jet writing head in place of the original cover, its base has the same shape and the same sizes as those of the original cover and includes at least two independent tanks (mutually reversibiy assembled by assembling means) each of which contains one of the inks to be transferred into a corresponding tank located inside the body of the ink- jet writing head to re-load the said head. PRIOR ART The printers are one of the most known and widespreaded terminals which can be that can be advantageously used in many technical fields as, for example:
- telecommunications systems, where said printers can operate either alone (telewriters, facsimile, etc.) or within however complex telecommunications systems, of which they are one of the output means;
- data processing systems of any size and power (from desktop processors to a computerized data-processing centre of a large company) of which they are one of the most widespreaded interface means with the user, when they are not the sole interface means.
Many types of printers are available on the market, and they can be classified according to many features such as, for example, the writing head, which in its turn can be classified according to the printing system used (impact heads, ink-jet heads, thermal heads and so on); further details and/or classifications of the printers and/or of the writing
heads are omitted herein because they are outside the scope of the present disclosure.
For the same reason, in the present disclosure only ink-jet writing heads (and particularly three-colour ink-jet writing heads) will be discussed, omitting the other functional units which constitute a printer. Some three-colour ink-jet writing heads comprise a fourth tank, containing a black ink.
A multi-colour ink-jet writing head comprises at least three tanks, each of which contains an ink of different colour (red, green, blue and black, if any), and printing means (driven by the printer logic unit, which in turn can be driven by a higher-level logic unit) which draw one of the above inks from its respective tank for jetting ink microdrops on a backing (normally but not necessarily a paper one) to realize the required written and/or graphic text. An ink-jet writing head (and particularly a multi-colour ink-jet writing head) is expensive because the printing means are realized through technologically advanced manufacturing processes and by using materials having particular chemical and physical features carefully checked. Even if the manufacturers define this writing head as "disposable", it appears expensive to have to replace and to discard a working ink-jet writing head only because the ink loaded by the manufacturer into the head tank is exhausted. The manufacturers widely demonstrated that, by using inks suitably designed for a specific application, it is possible to extend the useful life of an ink-jet writing head well beyond the exhaustion of the original ink load.
Many re-loading devices are commercially available, developed by manufacturers of printing fittings, which allow to re-load one or more times a one-colour or multi-colour ink-jet writing head.
The access to a tank located inside an ink-jet writing head can be achieved either by removing the means, if any, used by manufacturers to close the hole used for the first loading of the corresponding ink (red, blue, green or black) into the ink-jet writing head, or by drilling a proper hole into the ink-jet writing head covering.
Re-loading devices consisting of coverings (syringes, pumps, bellows, etc.) containing an ink, providing different shapes and/or sizes and being a low ergonomic levels are known for example from U.S. Patent No. 5,199,470; the user must therefore perform a sequence of operations that are not always easy and safe, particularly as regards the risk of an uncontrolled leakage of the ink from the ink-jet writing head after the related tank (not completely empty upon re-loading and/or having a smaller volume than the loader one) has been completely re-loaded with ink. Ink re-loaders for ink-jet writing heads which allow the gradual and controlled supply of at least part of the ink contained in said re-loaders, solving the above-mentioned disadvantages of the previously-described loaders are known in the art. Said re-loading devices (easy to manufacture, inexpensive, preferably made of a recyclable plastic material and lacking in metal parts) are perfectly suitable for ink-jet writing heads, for the re-loading of which they have been designed and realized.
The re-loading device object of the present invention is an improvement of the already known ones, since it allows a further reduction of the manual ability required to fill up the ink-jet writing head thus reducing the risk, already very small, of accidental ink leakages and allowing to re-load and therefore to re-use many times ink-jet writing heads which are re-loadable with difficulty with previously-known re-loaders, like ink- jet writing heads having rigid tank and inner pressure compensation
systems and those comprising one or more tanks in foam material balanced with the outside. SUMMARY OF THE INVENTION
Object of the present invention is a re-loading device for ink-jet writing heads, whose base has the same shape and the same sizes as those of the original cover and that therefore is suitable to be reversibly connected to the body of the ink-jet writing head in place of the original cover.
The re-loading device includes, in mutual combination: - at least two independent tanks, each of which contains one of the inks to be transferred into a corresponding tank located inside the body of the ink-jet writing head;
- reversible assembling means, to mutually assemble said independent tanks; - transfer means to transfer ink from at least one of said independent tanks belonging to the re-loading device to the corresponding tank (or corresponding tanks) positioned inside the body of the ink-jet writing head;
- connecting means which reversibly connect the re-loading device to the body of the ink-jet writing head.
When at least one of its independent tanks is empty, the re-loading device can be manually separated from the body of the ink-jet writing head, disassembled to replace the empty tank(s) with as many full tank(s), again assembled anOd again connected to the body of the ink- jet writing head. LIST OF FIGURES
The invention will be better described with reference to a non limiting embodiment suitable to re-load a three-colour ink-jet writing head and shown in the enclosed drawings, wherein:
- figure 1 schematically shows a side view of a re-loading device realized according to the invention, connected to the body of a three- colour ink-jet writing head;
- figure 2 shows a top view of the upper side of the body of the three- colour ink-jet writing head of figure 1 ;
- figure 3 shows a top view of the re-loading device of figure 1 ;
- figure 4 shows a side view of the re-loading device of figure 1 , without reversible connecting means;
- figure 5 shows a front view of the re-loading device of figure 1 ; - figure 6 shows a bottom view of the re-loading device of figure 1 ;
- figure 7 shows a rear view of the re-loading device of figure 1 ;
- figure 8 shows a top view of the re-loading device of figure 1 , without the upper cover 6;
- figure 9 shows a sectional view of the re-loading device of figure 4 made according to the section plane A-A of figure 3;
- figure 10 shows a sectional view of the re-loading device of figure 4 made according to the section plane B-B of figure 3;
- figure 11 respectively shows a top view and a sectional view made according to the section plane D-D of three independent tanks belonging to the re-loading device of figure 1 , mutually spaced and without reversible connecting means, and a sectional view made according to the section plane E-E of one of said independent tanks;
- figure 12 respectively shows a top view and a sectional view made according to the section plane F-F of the lower areas of the independent tanks of figure 11 (including the reversible connecting means not shown in figure 11), and a sectional view made according to the section plan G-G of one of said lower areas;
- figure 13 respectively shows a top view and a sectional view made according to the section plane H-H of sealing gaskets that can be interposed between independent tanks of the re-loading device of figure
1 and the body of the ink-jet writing head, and a sectional view made according to the section plane l-l of one of said gaskets. In the enclosed figures, the corresponding elements are designed by the same reference numerals. DETAILED DESCRIPTION OF THE INVENTION
Figure 1 schematically shows a re-loading device 10 for ink-jet writing heads, embodied according to the invention, connected to the body 11 of a three-colour ink-jet writing head, which is not described in detail herein because it is known per se: as shown in the top view of figure 2, the upper side of the body 11 is provided with three sets of three holes (12, 13), where at least some of the lateral holes 12 are used to connect the original cover to the body 11 , while the central holes 13 are used for the first loading of each ink into the corresponding tank of the three-colour ink-jet writing head. The base of the re-loading device 10 realized according to the invention has shape and sizes corresponding to those of the base of the original cover and is therefore suitable to be secured (through adequate reversible connecting means) to the body 11 of the ink-jet writing head as a replacement for the original cover. The re-loading device 10 comprises three independent tanks 3 mutually assembled by reversible assembling means that, in the embodiment herein described, are composed of an upper cover 6 snappingly engaged on projections (or "undercuts") 110 (figures 4, 9 and 11 ) realized for this purpose on the independent tanks 3 located at the two ends of the re-loading device 10.
Each of the independent tanks 3 is adapted to contain one of the inks to be transferred (through suitable transfer means) into the corresponding tank positioned inside the body 11 of the ink-jet writing head to be re-loaded.
Without departing from the scope of the invention, it is possible to mutually assemble, through the above reversible assembling means, at least one independent tank 3 containing one of the inks to be transferred into the corresponding tank positioned inside the body 11 of the ink-jet writing head and at least one empty independent tank 3. Figures 3 to 7 show orthogonal views of the re-loading device 10 of figure 1 : in these figures there are shown:
- the independent tanks 3 (figures 4 and 6) assembled by the upper cover 6 (figure 4); - pierced pins 2, each of which is connected to one of the independent tanks 3 of the re-loading device 10 that contains an ink to be transferred into a tank positioned inside the body 11 of the ink-jet writing head;
- reversible connecting means to connect the re-loading device 10 to the body 11.
In the present embodiment the reversible connecting means are realized through pairs of resilient hooks 4 (omitted in the side view of figure 4) positioned besides one of the pierced pins 2 (figures 5 to 7, where said resilient hooks are elastic fork-shaped elements) and suitable to be reversibly engaged with the lateral holes 12 of the body 11 of the ink-jet writing head.
The re-loading device 10 can therefore be manually separated from the body 11 of the ink-jet writing head when at least one of its independent tanks 3 is empty. The pierced pins 2 are covered by protection caps 5, which must be removed before connecting the re-loading device 10 to the body 11 of the ink-jet writing head through the reversible connecting means. Figure 8 shows a top view of the re-loading device 10 in figure 1 , whose upper cover 6 (figure 4) has been removed to show the holes 7 realized
in the upper wall of the independent tanks 3 and closed by sealing plugs 71 (figure 11 ).
Figure 9 shows a sectional view (made according to the section plane A-A of figure 3) of the re-loading device 10 of figure 4: the upper cover 6 and the three independent tanks 3 are shown sectioned, where every independent tank 3 is connected to transfer means that include one of the above pierced pins 2 (covered by a protection cap 5) and the hole 7, pierced into the upper wall of the independent tank 3 and closed by a plug 71 (not shown in figure 9) that is removed by a user to transfer the ink loaded into the independent tank 3 to the corresponding tank positioned inside the body 11 of the ink-jet writing head. Figure 10 shows a sectional view (made according to the section plane B-B of figure 3) of the re-loading device 10 of figure 4: there are shown, sectioned, the upper cover 6 and one of the independent tanks 3, assembled by the upper cover 6, which is connected to the transfer means composed of the pierced pin 2 covered by the protection cap 5 and of the hole 7 closed by the plug 71 (not shown in figure 10) and to reversible connecting means, composed of a pair of resilient hooks 4 (in figure 10, a pair of plastic fork-shaped elements 4) positioned besides the pierced pin 2.
Figure 11 respectively shows a top view and a sectional view made according to the section plan D-D of three independent tanks 3 belonging to the re-loading device 10 of figure 1 , mutually spaced and without the reversible connecting means. Figure 11 also shows a sectional view made according to the section plane E-E of one of the above independent tanks 3. In particular, figure 11 shows the holes 7 (pierced into the upper wall of each of the independent tanks 3 and closed by plugs 71) and the projections 110 with which the upper cover 6 is snappingly engaged (figures 4 and 9) to
mutually assemble the independent tanks 3 belonging to the re-loading device 10.
Figure 12 respectively shows a top view and a sectional view made according to the section plane F-F of the lower areas of the independent tanks 3 of figure 11 , including the reversible connecting means not shown in figure 11.
Figure 12 further shows a sectional view made according to the section plane G-G of one of the above lower areas. From figure 12 it is possible to note that (in the embodiment shown in figure 12) the bottom surface 120 of each of the independent tanks 3 provides for a plurality of slightly inclined planes "converging" onto a hole 121 , pierced into the bottom surface 120 and directly connected with the relevant pierced pin 2; the reversible connecting means are composed of a pair of resilient hooks 4 (in figure 12, a pair of plastic fork-shaped element 4) positioned besides the pierced pins 2.
Figure 13 respectively shows a top view and a sectional view made according to the section plane H-H of the sealing gaskets 130 (preferably but not necessarily) interposed between the independent tanks 3 of the re-loading device 10 and the body 11 of the ink-jet writing head to prevent ink leakages when one of the tanks allocated inside the body 11 of the ink-jet writing head is re-loaded.
Figure 13 further shows a sectional view made according to section plane l-l of one of the above gaskets 130. Sealing gaskets 130 preferably comprise plane members (made of rubber or other functionally equivalent resilient material) whose sizes are substantially equivalent to those of the base of the corresponding independent tank 3: each of said plane members has one or more slots 131 (one slot in the embodiment shown in figure 13) whose sizes are such as to allow the passage of the pierced pin 2 belonging to the ink transfer means from the independent tank 3 of the re-loading device 10
to the corresponding tank of the body 11 of the ink-jet writing head and of the pair of resilient hooks 4 which are the elastic connecting means of the relevant independent tank 3. Without departing from the scope of the invention, the sealing gaskets 130 can be omitted.
According to another embodiment of the invention (not shown in the figures) the re-loading device 10 includes a further independent tank 3 containing a black ink to be transferred into a further tank positioned inside the body 11 of the ink-jet writing head through transfer means comprising a further pierced pin 2 and a further hole 7 pierced into the upper wall of the further independent tank 3 and closed by a further plug 71 , which is removed by the user to transfer the black ink from the further independent tank 3 of the re-loading device 10 to the further tank positioned inside the body 11 of the ink-jet writing head. The use of the re-loading device 10 of the present invention will now be briefly described.
Removed from the body 11 of the ink-jet writing head the original cover used by the manufacturer, a re-loading device 10 is connected to the body 11 of the ink-jet writing head through the reversible connecting means; the pierced pins 2, inserted into the corresponding holes 13 present on the upper side of the body 11 of the ink-jet writing head, connect the independent tanks 3 belonging to the re-loading device 10 to the corresponding tanks positioned inside the body 11 of the ink-jet writing head. When one of the tanks positioned inside the body 11 of the ink-jet writing head is empty, the user removes the upper cover 6 of the reloading device 10 and pulls out the plug 71 closing the hole 7 pierced into the upper wall of the independent tank 3 of the re-loading device 10 where the ink to be transferred into the tank in the body 11 of the ink-jet writing head is loaded: air goes into the independent tank 3
through the hole 7 and ink goes down by gravity from the independent tank 3 of the re-loading device 10 into the corresponding tank positioned inside the body 11 of the ink-jet writing head, thereby reloading said tank. Obviously, two or more tanks placed inside the body 11 of the ink-jet writing head can be simutaneously re-loaded by removing the plugs 71 closing the holes 7 pierced in the upper wall of the corresponding independent tanks 3 belonging to the re-loading device 10. Afterwards, the user manually separates, through the reversible connecting means, the re-loading device 10 from the body 11 of the ink-jet writing head; removes the upper cover 6 to separate the independent tanks 3 of the re-loading device 10; replaces the empty independent tank 3 (or the empty independent tanks 3) with as many full independent tanks 3; assembles again through the upper cover 6 the re-loading device 10 and finally connects again it to the body 11 of the ink-jet writing head.
Without departing from the scope of the invention, a skilled person can carry out on the re-loading device for ink-jet writing head of the present invention all modifications and improvements suggested by his usual experience and by the natural evolution in the art.