MXPA06004265A - A liquid jet head and a liquid ejecting instrument including such a liquid jet head - Google Patents

Abstract

A liquid jet head (5) designed to be mounted on a liquid ejecting instrument (1), said liquid jet head (5) comprising:- a substrate (7) - a liquid jet system (9) positioned on the substrate (7), and measurement means (13) for acting without physical contact with the medium (8) to measure the distance between the liquid jet head (5) and the medium (8), the measurement means (13) being designed to be coupled to a control unit (10), the measurement means (13) is positioned on the substrate (7).

Description

LIQUID SUPPLIER HEAD AND AN EXPULSING LIQUID INSTRUMENT INCLUDING SUCH LIQUID SUPPLIER HEAD The present invention relates to liquid dispenser heads, and to liquid ejector instruments including such liquid dispenser heads. The liquid ejecting instruments may be formed by liquid dispensing printers or writing devices containing the same and in particular those devices which employ the non-contact transfer method of the ink to a writing medium. The present invention also relates to ink ejector or liquid instruments that are designed to be held in the hand of a user. More particularly, between such liquid dispenser heads, the present invention relates to a liquid dispenser head designed to be mounted on a liquid ejector instrument, the liquid dispenser head comprising: a substrate that is adapted to be mounted on the ejector instrument liquid, and a liquid spout system placed on the substrate, the liquid spout system adapting to eject the liquid on a medium from a distance, the liquid spout system being further designed to be coupled to a control unit that serves to activate the system liquid spout to expel the liquid on the medium.

In such a known liquid ejecting instrument, the liquid dispenser head can comprise a substrate and a liquid dispensing system including at least one nozzle or a plurality of nozzles that are placed directly on the substrate. In the case where the liquid dispenser head is formed by a thermal ink head, the ink system generally comprises at least one resistive heating element which is fixed on one side of the substrate, and a block mounted on the same side of the substrate. The block has at least one ink channel extending between an inlet chamber and an outlet orifice facing the at least one resistive heating element. The outlet orifice forms the nozzle which is adapted to eject droplets of ink on the medium by an explosive formation of a vapor bubble within the ink in contact with the resistive heating element. In known ink dispensing printers, the recording medium, mainly an ink receiving member, such as paper or other writing surface, is fed into the printer and the image is made while conveying the medium in a perpendicular direction. to the direction in which the ink supply head moves. As a result, it can happen that the ink is inadvertently ejected from the ink jet system, and more particularly from at least one nozzle of the ink jet system placed on the substrate. For example, ink droplets can be ejected accidentally before the nozzle of the ink jet system has correctly opposed the medium.

On the other hand, when the liquid ejecting instrument is formed by an ink supply pen comprising a tubular instrument intended to be held in the hand of a user, the tubular element has a sensor having a first end which serves to enter contact with the medium during writing, and a second end that is connected to a movement detection mechanism to detect the movement of the sensor in contact with the medium. That motion detector mechanism is connected to the control unit to allow the liquid dispensing head to activate. Therefore, although the liquid dispensing head is not necessary to come into contact with the medium, it is nevertheless essential for the pen sensor to come in contact with the medium in order to be able to initiate the ejection of the liquid. Therefore, it may be convenient for the user to place the sensor in contact with the particular medium when the medium is rigid to some degree. further, since the end of the sensor in contact with the medium is generally close to the point of impact of the medium liquid jet, there is a greater risk of the end of the sensor coming into contact with the liquid before it dries, smearing it so on the medium while the ink supply pen is in normal use. The present invention alleviates the aforementioned technical problems by providing a liquid dispenser head designed to be mounted on a liquid ejector instrument, for example, such as an ink dispenser printer, in which the liquid dispenser head is too reliable to make possible to prevent liquid droplets from being ejected accidentally, when said liquid dispensing head has not been properly opposed to the medium, or when the liquid ejecting instrument is formed by an ink supply pen to provide a reliable liquid dispensing head and procure good writing comfort for the user. In this aspect, the invention provides a liquid dispenser head designed to be mounted on a liquid ejector instrument, said liquid dispenser head comprising: a substrate that is designed to be mounted on the liquid ejector instrument, and a liquid dispenser system positioned on the substrate, the liquid spout system adapting to eject the liquid on a medium from a distance, the liquid spout system being further designed to be coupled to a control unit that serves to activate the liquid spout system to eject the liquid on said liquid spout. medium. characterized in that the liquid dispensing head further comprises measuring means for acting without physical contact with the means for measuring the distance between the liquid dispensing head and the medium, the measuring means being designed to be coupled to the control unit, and because the Measurement medium is placed on the substrate. Various embodiments of the invention may additionally include any of the following conditions: the control unit is also placed on the substrate; the measuring means comprises an optical system that serves to measure the distance between the liquid dispensing head and the medium; the measuring means comprises an ultrasonic acoustic meter which serves to measure the distance between the liquid dispensing head and the medium; the substrate comprises a supply channel extending between an inlet port designed to be connected to a liquid tank housed within the liquid ejector instrument, and an outlet port connected to the liquid jet system; the substrate is made of material comprised of a group consisting of glass, silicon, ceramic and polymer materials; - the liquid jet system comprises a thermal fluid jet system adapted to eject droplets of liquid from at least one orifice by an explosive formation of a vapor bubble within the liquid contained within the liquid jet system; the substrate is formed by a plate having a first side designed to face the medium and a second side opposite the first side, and wherein the thermal liquid jet system comprises: • at least one resistive heating element that is fixed on the first side of the substrate, and • a block mounted on the first side of the substrate, the block having at least one liquid channel having an inlet chamber and an outlet orifice that is facing at least one resistive heating element for eject droplets of ink on the medium; the movement detecting means is also placed on the substrate, the movement detecting means being adapted to detect the movement of the liquid dispensing head and the movement detecting means also designed to be coupled to the control unit. In addition, the present invention also provides a liquid ejector instrument comprising a substantially tubular member extending between a first end and a second end and designed to be held by hand by a user, the tubular member comprising: a liquid tank; a source of electrical energy, and - a liquid dispenser head as defined above, the liquid dispenser head being mounted on the first end of the tubular member and connecting to the source of electrical energy. Other features and advantages of the invention will appear on reading the following description of the modalities thereof, given by way of non-limiting example, and with reference to the accompanying drawings. In the drawings: Figure 1 is a schematic cross-sectional view of a liquid ejector instrument provided with a liquid dispenser head according to a first embodiment of the invention; figure 2 is an extended cross-sectional view of a part of the liquid ejector instrument of figure 1, showing in detail the liquid dispensing head according to the first embodiment; Figure 3 is a perspective view showing one side of a liquid dispenser head according to the first embodiment; Figure 4 is an exploded perspective view showing another side of the liquid dispenser head of Figure 3; Figure 5 is a block diagram of the various component elements that can be integrated into the liquid dispenser head; Figure 6 is a schematic cross-sectional view of a liquid ejector instrument provided with a liquid dispenser head according to another embodiment of the invention; and Figure 7 is an enlarged cross-sectional view of a part of the liquid ejecting instrument of Figure 6, showing in detail the liquid dispensing head. In the various figures, the same references designate elements that are identical or similar. Figure 1 shows a liquid ejector instrument 1 having a substantially tubular element 2 extending between a first end 2a and a second end 2b to form a pen. The tubular element 2 has an internal wall 21 defining an empty internal space, and an external wall 22 designed to be held in the hand of a user. The empty internal space defined by the inner wall 21 of the tubular element 2 contains an electric power source 3, a liquid tank 4 and a liquid dispenser head 5 at the first open end 2a of the tubular element, the liquid dispenser head 5 associating directly with the liquid tank 4 through a fluid communication. The electric power source 3 housed in the empty internal space of the tubular element 2 can be formed, for example, by a battery or a plurality of batteries that can be rechargeable, making it possible, by means of a switch 6 located at the second end 2b of the tubular element 2, ignite the various electrical elements of the liquid dispenser head 5. The electric power source 3 and the liquid dispenser head 5 are connected by means of two power lines 31. The switch 6 can be replaced by any ignition means that can be operated by the user of the instrument, and in particular, by means of detecting that the tubular element 2 is being held in the user's hand, and such as, for example, a sensor capacitive placed on the external wall 22 of the tubular element 2 and which serves to detect the pressure when the user takes possession of the instrument. By way of example, the end 2b of the tubular element can be in the form of a cover removably mounted in the central part of the tubular element 2 to allow the power source 3 to be replaced by a new source of electrical energy . The liquid tank 4 can also be mounted removably in the empty internal space of the tubular element 2 in order to be replaced by another tank since the liquid has left. Depending on how the instrument is used, the liquid contained in the tank may be formed by an ink, or by an ink-masking or ink-erasing liquid when the instrument is used as a concealer, or in turn by an adhesive when said The instrument is used as a sprayer or adhesive applicator, the liquid having sufficient properties to be expelled from the liquid dispensing head 5. As illustrated in FIGS. 1 and 2, in the example considered therein, the liquid dispensing head 5 it is placed on the open end 2a of the tubular element 2. The open end 2a can be constituted by a fixed end piece directly towards the inner wall 22 of the central part of the tubular element 2. The liquid dispenser head 5 comprises a substrate 7 which can mounted on the inner wall 21 of the tubular element 2. The outline of the substrate 7 and the inner wall 21 of the tubular element have complementary shapes that can be be circular, rectangular, square or triangular. The outline of the substrate 7, as shown in FIG. 2, is fixed directly on a flange 21 formed on the inner wall 21 of the tubular element 2. The contour of the substrate 7 can be fixed on the flange 21 a of the inner wall 21 by adhesive means, welding, clamping or other fixing means. The substrate 7 can be made of glass or silicone or ceramic or other electrical insulators. As illustrated in Figures 2 to 5, the substrate 7 according to the first embodiment is formed by a circular horizontal plate having a first side 71 designed to be facing a medium 8 or writing surface and a second side 72 opposite the first side 71, the second side 72 facing the liquid tank 4. The liquid dispenser head 5 further comprises a liquid jet system 9 placed on the first side 71 of the substrate 7, the liquid jet system 9 adapting itself to eject the liquid on the medium from a distance and without physical contact with the medium 8. In addition, the substrate 7 may also comprise, on its second side 72, a control unit 10 which serves to activate the liquid jet system 9 for ejecting the liquid on the medium 8. The control unit 10 may include an electrical signal generator (or electrical pulse) to enable the liquid jet system 9 to eject droplets of liquid on medium 8 from a distance. The liquid spout system 9 can be formed by a thermal fluid spout system adapted to eject droplets of liquid from at least one orifice by the explosive formation of a vapor bubble within the liquid contained in the liquid spout system. As illustrated in Figure 3 and 4, the thermal liquid spout system 9 may comprise at least one resistive heating element 91 fixed on the first side 71 of the substrate 7 and which is coupled to the electrical signal generator of the control unit 1 0, and a block 1 1 mounted on the same first side 71 and covering the resistive heating element 91. More particularly, the block 1 1 has at least one liquid channel 12 extending between an internal chamber 12 a comprising a lower part and an outlet hole 12 b which is designed to face the resistive heating element 91 fixed on the substrate 7. The exit orifice 12b is shaped and adapted to allow the ejection of fine droplets when the electrical signals are applied from the generator to the resistive heating element 91 in order to instantaneously increase the temperature of said resistive heating element. 91, thereby forming a vapor bubble in the liquid, whose bubble ejects a fine droplet of liquid onto the medium. The liquid channel 12 also comprises a central part 12c which connects the internal chamber 12a towards the outlet orifice 12b, thereby providing a capillary channel 12 for the liquid to flow towards the resistive heating element 91. The substrate 7 also comprises a supply channel 73 extending between an inlet port 73a connected to a supply conduit 41 of the liquid tank 4 (Figure 2) and an outlet port 73b opening into the internal chamber 12a of the block 1 1 when said block is placed and fixed on the first side 71 of the substrate 7. In this embodiment, the liquid capillary channel 12 is located at the interface of the substrate 7 and the block 1 1 and is sealed by the fixing of the block on the first side 71 of the substrate 7. Typical materials used for the substrate 7 are electrical insulators such as glass, ceramics, a coated material or silicone, while the materials used for the block 1 1 are generally chosen for their ease of manufacture in respect of to the liquid capillary channel 12. For example, block 1 1 can be made of molded glass, cut silicone or cut glass. The block 1 1 can also be formed by a metal plate. In this interpretation, the substrate 7 and the block 1 1 can be sealed together in a variety of ways, for example, by epoxy, anodic bond or with sealed glass. However, the liquid jet system 9 can also be formed by a piezoelectric jet system including a piezoelectric element instead of the resistive heating element 91., the piezoelectric element adapting to deform when subjected to electrical signals coming from the generator of the control unit 1 0. The liquid jet system 9 can also operate using MEMS (Micro Electro Mechanical System) technology or a combination of piezoelectric technology, thermal and / or MEMS. The liquid-dispensing head 5 also comprises measuring means 13 directly placed on the substrate 7. The measuring means 13 is adapted to act without physical contact with the means 8 for measuring the distance between the liquid-dispensing head 5 and the medium 8. More precisely, the measuring means 13 can be adapted to measure the distance between the liquid system head 9 and the medium 8. In the example considered here and as illustrated in FIGS. measuring means 13 is constituted by an optical system comprising, for example, at least one infrared light emitting diode (LED) 14 which sends an incident light beam Fl towards the medium 8 in order to form a light spot on the medium 8 together with a beam of reflected light FR. The light spot and the reflected light beam FR are detected by one or a plurality of optical sensors 15 in order to determine the inclination angle of the incidental beam Fl in relation to the medium and intensity of the light spot. Since the distance between the infrared LED 14 and the optical sensor 1 5 is known per se, and since the angle of inclination of the incidental light beam F1 and the intensity of the light spot are determined, it is thus merely necessary to use simple trigonometric relationships to determine the distance between the infrared LED 14 and the medium 8, and therefore between the liquid jet system 9 and the medium 8. The infrared light can also be modulated to reduce the possibility of interference with daylight during the determination of the calculated distance. The optical sensor 15 is typically formed by the semiconductor diode or phototransistor or photodiode such as the infrared photodiode SFH229 sold under the trademark SIEMENS. The infrared emitter can be formed by the emitter IF OPE5794 sold under the OPTEK brand.

In the embodiment illustrated in Figure 3, the measuring means 1 3, which is connected to the control unit 10, comprises a plurality of infrared light emitting diodes 14 and a plurality of optical sensors 15 placed in the ring shape, each light-emitting diode 14 being placed between both optical sensors 15, and each optical sensor 15 being placed between both light-emitting diodes 14, such that a light-emitting diode 14 and the corresponding optical sensor oppose each other diametrically. In this exemplary embodiment, there are three infrared light emitting diodes 14 and three optical sensors 15. Of course, the measuring means may include more than three diodes 14 and sensors 15. In the embodiment as illustrated in FIG. Measurement 1 3 is placed on the second side 72 of the substrate 7 that is made of glass in order to allow the incidental light beams Fl and the reflected light beams to reach through the substrate 7. However, when the substrate 7 is made of opaque material, the measuring means 13 can also be placed on the first side 71 of the substrate directly facing the medium 8. In another embodiment, the measuring means can also have means for emitting a conical beam of light or a plurality of conical light beams whose axis of symmetry substantially coincides with the longitudinal axis of the tubular element 2. The measuring means 1 3 then has an optical sensor or a plurality of optical sensors adapted for determine the radius of the corresponding light spot formed by the corresponding conical beam on the medium 8. Since the radius of the light spot is proportional to the distance between the medium 8 and the emitting medium to emit the conical beams, then it is it is possible to measure in a linear or non-linear manner the distance between said emitting medium and the medium 8. Similarly, if the axis of symmetry of the conical beam is inclined in relation to the medium, the light spot or the plurality of light spots formed on the medium it is not more circular, but at the same time it is elliptical, and the sensor or the plurality of sensors is also adapted to measure the length of the minor axis of the corresponding elliptical spot in order to measure the corresponding distance between the medium and the issuing members of the issuing media. In this case, and without considering the inclination of the liquid ejector instrument 1, the length of the minor axis of each elliptical spot is proportional only to the distance between the medium and each corresponding emitter of the emitting medium, and it is only the length of the main axis of each elliptical spot which is to provide the corresponding conical beam inclination angle. According to another method, the distance between the liquid system head 9 and the medium can be calculated with the at least one optical sensor by detecting the amplitude of the infrared light reflected from the surface of the medium 8. In a variant mode (not shown), the measuring means 13 can also be constituted by an ultrasonic acoustic meter or a plurality of ultrasonic acoustic meters placed directly on the substrate 7.

As can be seen with reference to Figure 5, the measurement means and more particularly each infrared LED 14 and each optical sensor 15 is directly coupled to the control unit 10 which can store the measurements taken by the measuring means 13. The unit Control 10 can also be adapted to cause measurement means 13 to make repeated measurements at certain time intervals. Such time intervals, for example, could be in the range of 1 millisecond (ms) to 0.1 second (s). In this case, the control unit 1 0 can thus determine the displacements of the liquid dispensing head 9 in relation to the medium 8 as a function of a plurality of distances measured by the measuring means 13 in a plurality of intervals of determined time. As described above, the three infrared emitting diodes 14 can send three different incidental light beams Fl towards the medium 8 in order to form three spots of light on said medium 8 with three beams of reflected light FR detected by the three optical sensors 15. Consequently, when at least one optical sensor 15 detects a variation of the distance in combination with its corresponding infrared LED 14 diametrically opposite, the control unit 10 can interpret that variation as movement of the liquid dispensing head. Such relative displacements are only detected when the liquid dispenser head 9 does not move in a plane that is strictly parallel to the plane of the medium. However, when a normal user is using a writing instrument for writing, the user automatically transmits tremors to the tubular element 2, such tremors are automatically detected by the measuring means 13 and by the control unit as being a movement. Consequently, the control unit can be adapted to cause the liquid spout system 9 to be activated when the measuring means 13 determines that the distance between the medium and the liquid spout system 9 is in an appropriate range or when both the The measuring means determines that the distance is in an appropriate range and that the control unit 10 together with the measuring means 1 3 detects a movement of the liquid spout system 9. However, the substrate 7 may also comprise a medium movement detector 16 (figure 3) directly placed on one of the first and second sides, 71, 72 of said substrate 7. The movement detecting means 16 can also be placed in another place, for example, on the internal wall 21 of the tubular element 2. The movement detecting means 16 can be formed, for example, by an accelerometer, an inclination sensor or a vibration detector. Figures 6 and 7 show the liquid ejector instrument 1 including a liquid dispenser head 32 according to another embodiment of the present invention. The liquid-dispensing head 32 is also placed on the open end 2a of the tubular element 2 which can be constituted by a fixed end piece directly on the inner wall 21 of the central part of the tubular element 2. In this second embodiment, the head assortment of liquid 32 comprises a substrate 33 formed by a vertical plate having an upper edge 33a facing the liquid tank 4, a lower edge 33b facing the middle and two side edges 33c mounted on the inner wall on the end open 2a of the tubular element. The contour of the side edge 33c and the inner wall of the open end 2a of the tubular element 2 have complementary shapes and the side edges 33c can be fixed on the inner wall by adhesive, welding, or by any suitable means. The substrate 33 also has two parallel sides extending along the longitudinal axis of the tubular element 2. The liquid dispensing head 32 further comprises a liquid jetting system 34 positioned near the lower edge 33b of the substrate 33. The jetting system of liquid 34 is of side trigger style with at least one resistive heating element 35 fixed on one side of substrate 33 and a block 36 mounted on the same side of substrate 33, block 36 having at least one liquid channel 37 extending between an inlet port connected to the supply line 41 of the liquid tank 4 and an inlet port in which the resistive heating element 35 is located. The substrate 33 and the block 36 can be made from materials such as those described for the head liquid dispenser 5 of the first mode. The liquid dispensing head 32 also comprises measuring means 13 placed on the substrate 33. The measuring means, in this embodiment, comprises an infrared light emitting diode (LED) 38 coupled to the light transporting means 39 and an optical sensor 40. coupled to the light transporting means 42. More particularly, the light transporting means 39 and 42 can be formed by one or a plurality of optical fibers or molded light pipes for transmitting the infrared to and from the lower edge 33b of the substrate 33. Consequently, the LED 38 sent an incidental light that it is transmitted by the light transport means 39 to the medium 8 in order to form one or a plurality of spots on the medium 8. Then, the reflected light is sent to the optical sensor 40 by means of the light transporting means 42 so as to to allow the determination of the distance between the middle and the lower edge 33b of the substrate. The various methods for calculating the distance between the medium and the head of the liquid system described for the first embodiment can be applied for this second embodiment. For example, the optical sensor 40 may be adapted to calculate the distance using the amplitude of the infrared light reflected from the surface of the medium 8. Each light transporting means 39, 42 may include one or more optical fibers or the like having a first coupled end with the . Corresponding LED 38 or corresponding optical sensor 40 and a second fixed end on one side of the substrate 33 or on the inner wall of the open end 2a of the tubular element 2. The substrate 33 may also comprise the movement detecting means 16 and the control unit 10, as already described in the first embodiment of the present invention. The liquid dispensing system 34 can also be formed by a piezoelectric dispensing head or a MEMS head. Accordingly, according to the invention, the liquid dispenser head 5; 32 can be constructed as a preassembled and hand-held unit comprising at least the substrate 7; 33, the liquid spout system 9; 34 and the measurement means 13, that pre-assembled unit mounted directly on the liquid ejector instrument 1 and connecting to the electric power source 3 by means of the power line 31. The control unit 10 may or may not be placed on the substrate 7; 33 if the liquid ejecting instrument is formed by an ink supply pen with a tubular element or ink dispenser printer. Consequently, when the liquid ejecting instrument is formed for example by an ink supply pen, the ink supply head 5; 32 forming a pre-assembled unit allows the user to raise the boom to a suitable distance in order to cause the ejection of fine ink droplets on the medium without requiring any physical contact with the medium 8 or writing surface.

In the same way, when the liquid ejecting instrument is formed by an ink dispensing printer, the preassembled unit that forms the ink supply head; to sharpen the substrate, the ink jet system and the measuring medium; it allows detecting the presence of the medium in the region of the ink jet system, thereby preventing an accidental expulsion of the ink on another object different from the medium.

Claims (10)

1. CLAIMS 1. A liquid dispenser head (5; 32) designed to be mounted on a liquid ejector instrument (1), said liquid dispenser head (5; 32) comprising: - a substrate (7; 33) adapted to be mounted on the ejector instrument of liquid (1), and a liquid dispensing system (9; 34) placed on the substrate (7; 33), said liquid dispensing system (9; 34) adapting to expel the liquid on a medium (8) from a distance, said liquid spout system (9; 34) further designed to be coupled to a control unit (10) that serves to activate said liquid spout system (9; 34) to eject the liquid on said medium (8), characterized because said liquid dispensing head (5; 32) further comprises measuring means (1 3) to act without physical contact with the medium (8) to measure the distance between the liquid dispensing head (5; 32) and the medium ( 8), the measuring means (13) being designed to be coupled to said control nature (10), and in that said measuring means (1 3) is placed on the substrate (7).
2. 2. A liquid dispenser head according to claim 1, characterized in that the control unit (10) is also placed on said substrate (7).
3. 3. A liquid dispensing head according to claim 1 or 2, characterized in that said measuring means (13) comprises an optical system (14, 15; 38, 39, 40, 41) that serves to measure the distance between said liquid dispenser head (5; 32) and the medium (8).
4. 4. A liquid dispenser head according to claim 1 or 2, characterized in that said measuring means (13) comprises an ultrasonic acoustic meter that serves to measure the distance between said liquid dispensing head (5) and the medium (8). A liquid dispenser head according to any of the preceding claims, characterized in that said substrate (7) comprises a supply channel (73) extending between an inlet port (73a) designed to be connected to a liquid tank (4). ) housed inside the liquid ejector instrument (1), and an outlet port (73b) connected to said liquid jet system (9). 6. A liquid dispenser head according to any of the preceding claims, characterized in that said substrate (7; 33) is made of material comprised in a group consisting of glass, silicone, ceramic and polymer materials. A liquid dispenser head according to any of the preceding claims, characterized in that said liquid dispensing system (9; 34) comprises a thermal liquid dispensing system adapted to eject droplets of liquid from at least one orifice (12b) by forming explosive of a vapor bubble within the liquid contained within said liquid jet system (9). A liquid dispenser head according to claim 7, characterized in that said substrate (7) is formed by a plate having a first side (71) designed to face the medium (8) and a second side (72) opposite to said first side (71), and wherein said thermal liquid spout system (9; 34) comprises: at least one resistive heating element (91) that is fixed on the first side (71) of said substrate (7), and a block (11) mounted on the first side (71) of the substrate (7), said block (11) having at least one liquid channel (12) having an internal chamber (12a) and an outlet orifice (12b) facing said at least one resistive heating element (91) to eject droplets of ink on the medium (8). A liquid dispenser head according to any of the preceding claims, characterized in that said movement detector means (16) is also placed on said substrate (7; 33), said movement detector means (16) being adapted to detect the movement of the liquid dispensing head (5; 32) and said movement detector means (16) also being designed to be coupled to said control unit (10). A liquid ejecting instrument (1) comprising a substantially tubular element (2) extending between a first end (2a) and a second end (2b) and designed to be held by hand by a user, said tubular element (2) ) comprising: a liquid tank (4), an electric power source (3), and a liquid dispensing head (5); 32) according to any of the preceding claims, said liquid dispensing head (5; 32) being mounted on the first end (2a) of the tubular element (2) and connecting to the electric power source (3).