Combined ink family keying for an ink cartridge

[0001] Inkjet printers operate by ejecting small drops of ink from the printhead onto a print medium, such as paper. The printhead generally includes a nozzle plate having a plurality of nozzles through which small droplets of ink are thrown onto the paper to form a picture together. To deliver ink to the nozzles, the print head is equipped with a plurality of drain chambers, each being fluidly connected to the associated nozzle through an opening. Inside each drain chamber there is a heat-generating resistor that is selectively powered to heat the ink in the chamber, which causes a bubble to form. As the bubble expands, some ink is pushed out of the paper nozzle through the opening. Although the configurations of individual printer models may vary, the print head and nozzles are often built into the print carriage inside the printer. The printhead can be integrated into the carriage or can be a removable detachable cartridge. In any case, the ink is delivered to the printhead through a cartridge, which is placed and attached with the option of detachment inside the printhead and carriage. The cartridge is fluidly and electrically connected to the print head and carriage by a fluid and electrical connector. The reliability of the cartridge and printhead assembly, and as a result the quality of the printed image, depends in part on the correct positioning and connection of the fluid and electrical connector. Inaccurate operation when entering or deleting

PAT-1252-EP-E

EP2107971 user cartridge or looseness between the cartridge and the printhead or carriage may result in loss of communication (e.g., loss of print command signal) or loss of print quality due to poor fluid connection. To ensure alignment and alignment of the cartridge inside the carriage, known cartridge designs have a built-in reference element that provides a reference point for inserting the ink cartridge. In this way, the cartridge is correctly positioned and connected within the carriage and / or printhead assembly to ensure proper fluid and electrical connections.

[0002] In addition to reference elements, known ink cartridges may include a wedging function to prevent placement of an incompatible ink cartridge. In some cases, ink cartridges are versatile and can be used in a number of different printer series. However, some ink cartridges contain inks that may be chemically incompatible with other types of inks. If incompatible inks come into contact with each other, they could freeze and damage the print head assembly and nozzles.

[0003] Although the ink cartridges may vary in size and shape, in the past they had a sufficiently large width and surface to accommodate both the reference element and the wedging elements. However, it has become increasingly important to design ink cartridges as narrow as possible because the overall width of the cartridge affects the width of the printer. With the arrival of narrower cartridges, their width is insufficient for the use of the reference element and the wedging element.

PAT-1252-EP-E

EP2107971 [0004] The embodiments described herein have been developed taking into account these and other disadvantages associated with the implementation of embedded reference components and wedging on narrow-width ink cartridges. EP0818314 describes a cartridge with a fluid ejecting printhead including a projection used to allow the cartridge to be located in the handle portion including a corresponding cavity and to prevent the cartridge from being positioned in the handle portion that does not include a corresponding cavity.

Summary of the Invention [0005] According to a first aspect of the present invention, there is provided a cartridge comprising: an insertion wedge disposed at the rear edge of the ink cartridge, the insertion wedge being designed to provide an axial reference point for placing the ink cartridge in the assembly ambulances; and, further, an insertion slot located on the front edge of the ink cartridge, the insertion slot being designed to receive an alignment post disposed on the carriage assembly to secure the ink cartridge in the carriage assembly. In accordance with a second aspect of the present invention, there is provided a system comprising: a carriage assembly; printhead assembly; and further one or more ink cartridges according to any of the preceding claims; wherein the carriage assembly is designed to receive one or more ink cartridges.

PAT-1252-EP-E

EP2107971

Brief description of the drawings [0006] Below, examples of embodiments of the invention will be described based on the attached drawings, in which:

[0007] Fig. 1 shows an exemplary inkjet printer in accordance with one embodiment.

[0008] Fig. 2 shows an exemplary isometric view of an ink cartridge according to one embodiment. [0009] Fig. 3 is another exemplary isometric view of an ink cartridge according to one embodiment.

[0010] Fig. 4 shows a partial placement of an exemplary ink cartridge in a printhead and carriage assembly in accordance with one embodiment.

[0011] Fig. 5 shows an exemplary ink cartridge completely inserted into the printhead and carriage assembly in accordance with one embodiment.

[0012] Fig. 6 is an isometric view of a carriage assembly and printhead in accordance with one embodiment. [0013] Fig. 7 is an isometric view of a printhead having an alignment post in accordance with one embodiment.

Detailed description [0014] The present invention relates to an ink cartridge having combined reference and wedging elements. The ink cartridge includes an ink supply connection, an electrical connection, and a prismatic low ink indicator. The combined reference and wedging element (that is, the "insertion wedge") serves as the axial reference point for controlling the position of the cartridge in the print carriage. In this

PAT-1252-EP-E

EP2107971 method, ink supply connection, electrical connection, and prismatic low ink indicator are correctly positioned relative to the printhead assembly and the printer carriage, ensuring proper fluid and electrical connection. [0015] Fig. 1 shows an exemplary inkjet printer 10 having at least one ink cartridge 12 attached to the printhead assembly 14 and carriage 16. Ink droplets are thrown onto print media such as paper

18, through the printhead, which usually includes multiple nozzles. The print head and nozzles can be built into the carriage 16, integrated into the ink cartridge 12 or, as shown in Figure 1, be a replaceable cartridge 14 located inside the carriage 16. In either case, the ink cartridge 12 supplies ink to the printhead assembly 14, which selectively ejects ink drops onto the paper 18 as the carriage 16 moves back and forth from one side of the printer 10 to the other in a bi-directional manner.

[0016] Fig. 2 is an exemplary isometric view of the ink cartridge 12 showing the front edge 20, the bottom surface 22 and the first side 24. The ink cartridge 12 includes an ink supply connection 26, an electrical connection 28 and a retaining clip 30 for mounting the ink cartridge 12 in the carriage 16 after inserting it. In one embodiment, the retention latch 30 extends across at least the front edge 20 of the cartridge 12. In a further embodiment, as shown in Fig. 2, the retaining latch 30 is a one-piece molded structure that corresponds to the length of the front edge 20 and extends across the upper surface 32. Ink supply connection

PAT-1252-EP-E

EP2107971 and the electrical connection 28 are located on the lower surface 22 and interlockingly connected to associated sockets (not shown) located in the printhead 14 and the carriage 16. After connection, the ink supply connection 26 and the electrical connection 28 ensure fluid and electrical communication between the ink cartridge 12 and printhead 14 and carriage 16.

[0017] The lower surface 22 of the cartridge 12 further includes a prismatic no ink indicator 34 that functions in conjunction with the optical sensor 36 (shown in Figures 1 and 6) in the carriage 16 to detect when there is no ink in the ink cartridge 12. In particular, the optical sensor 36 includes an emitter and a detector, wherein the emitter emits light to one side of the prism. If there is ink in the cartridge 12, the emitted light penetrates the ink and diffuses into the cartridge 12, preventing light from being reflected back onto the detector. If there is no ink in the cartridge 12, the emitted light is reflected back to the detector, indicating that the cartridge 12 is empty. In one embodiment, the prismatic no-ink indicator 34 also includes a transparent window that allows the user to assess the amount of ink inside the cartridge 12.

[0018] Fig. 3 is another exemplary isometric view of the ink cartridge 12 including the upper surface 32 and the rear edge 38. The rear edge 38 includes an insertion wedge 40 that provides an axial reference point for placing the cartridge 12 in the carriage 16. Placing the cartridge 12 in the printhead assembly 14 and carriage 16 is generally shown in Figs. 4 and 5, with Fig. 4

PAT-1252-EP-E

EP2107971 shows partial placement of the cartridge 12, and Fig. 5 shows the cartridge 12 completely inserted. Arrow 42 indicates the location of the ink cartridge 12 positioned in the printhead 14 and carriage 16 assemblies, the insertion wedge 40 engaging the wedging seat 44 and providing an axial reference point. The ink cartridge 12 is then rotated down to engage the retention latch 30 in the fully positioned position shown in Fig. 5. An insertion wedge 40 ensures that the ink cartridge 12 is properly positioned in the printhead and carriage 16 assemblies for proper fluid and electrical connections. For example, after correct and complete placement, the ink supply connection 26 is fluidly connected to the fluid connection 46, which is located on the printhead 14. In addition, in the fully positioned position, the electrical connection 28 is electrically connected to the electrical connection 48, which is located on the carriage 16.

[0019] In addition to controlling the movement of the cartridge 12 in the printhead assemblies 14 and carriage 16, the insertion wedge 40 also provides a wedging function to prevent the installation of an incorrect ink cartridge in the carriage 16. In other words, the insertion wedge 40 is designed such that the ink cartridge 12 can only be placed and properly seated in printhead and carriage 16 assemblies if there is a socket with a matching configuration. Fig. 6 shows sample configurations of printhead 14 and carriage 16, with printhead assembly 14 being placed in carriage 16. Wedge

PAT-1252-EP-E

EP2107971 for insertion 40, as shown in Figure 3, has the shape of an inverted T that fits into the wedging seat 44 located on the rear surface 50 of the carriage 16, as shown in Figure 6. It is understood by a common person skilled in the art that the exact configuration of the insertion wedge 40 and the matching wedging seat 44 may differ and that the inverted T shape of the insertion wedge 40 shown in Fig. 6 is only an example. For example, in an alternative embodiment, the insertion wedge 40 and the matching wedging seat on the carriage 16 may be L-shaped. [0020] Fig. 7 is an isometric view of an example carriage 16, the front plane 52 of the carriage 16 including an alignment post 54. A post alignment 54 is used in conjunction with the insertion slot 56 on the ink cartridge 12 (shown in Fig. 2) to further control the introduction of the cartridge 12 into the carriage 16. The alignment post 54 is particularly advantageous in printer configurations in which the width of the carriage is greater than the width of the ink cartridge 12.

The outer projection of the alignment post 54 engages with the insertion slot 56 to align and secure the ink cartridge 12 to the carriage 16, independent of the side walls of the printhead 58 (shown in Figs. 6 and 7).

[0021] While the present invention has been shown and described in particular in relation to its above embodiments, one of ordinary skill in the art will recognize that various alternative solutions for the embodiments of the invention described herein may be implemented without departing from the scope of the invention as defined in the following claims.

PAT-1252-EP-E

EP2107971