Ink cartridge detecting mechanism, ink jet printer, and ink cartridge

[0001] [Technical field to which the invention belongs] The present invention relates to an ink cartridge detection mechanism that detects an ink cartridge attachment / detachment state in a cartridge holder. The present invention also relates to an inkjet printer provided with the ink cartridge detection mechanism and an ink cartridge used in the ink cartridge detection mechanism. [0002] [Conventional technology] Inkjet printers that form characters and images on a print medium by ejecting ink supplied from an ink tank onto a print medium from a print head have become widespread. In this type of inkjet printer, a cartridge type ink tank (hereinafter referred to as an ink cartridge) is widely adopted in order to facilitate ink replenishment. [0003] In the above inkjet printer, the ink remaining amount and the detached state of the ink cartridge are detected in order to prevent printing defects caused by insufficient ink remaining amount in the ink cartridge or not installed in the ink cartridge, or to warn them. Is required, and a mechanism has been proposed that enables the same reflective optical sensor to detect the amount of ink remaining in the ink cartridge and the attachment / detachment of the ink cartridge (see, for example, Patent Document 1 and Patent Document 2). [0004] The detection mechanism irradiates two reflective parts (prisms) formed on the bottom of the ink cartridge with light from an optical sensor, and detects the remaining amount of ink and the detached state based on the amount of the reflected light received. .. That is, the reflective unit for detecting the remaining amount of ink has light transmittance so that the reflectance (intensity of reflected light) changes according to the remaining amount of ink, while the reflection for detecting the attached / detached state. The part is mirror-treated so as to reflect light regardless of the remaining amount of ink. [0005] [Patent Document 1] Japanese Unexamined Patent Publication No. 10-230616 [Patent Document 2] Japanese Unexamined Patent Publication No. 9-174877 [0006] [Problems to be Solved by the Invention] However, the above-mentioned conventional inkjet printer has the following problems. (1) Since it is necessary to provide two reflective parts formed of separate members on the ink cartridge, the number of parts and the manufacturing process increase, which leads to an increase in the cost of the ink cartridge. (2) Since the reflective part of the ink cartridge is exposed inside the printer even during the printing operation, dirt such as ink scattered during the printing operation adheres to the reflective part, and the detection by the optical sensor becomes unstable. There is a possibility of becoming. (3) When the optical sensor receives the reflected light, it is judged that the ink cartridge is in the mounted state. Therefore, when the optical sensor receives the ambient light, it is mistakenly recognized that the ink cartridge is in the mounted state even if it is not mounted. , Printing operation may be performed. [0007] An object of the present invention is to detect the attachment / detachment state of an ink cartridge with a reflective optical sensor, but it is not necessary to provide a reflection portion for the attachment / detachment detection on the ink cartridge, and the cost of the ink cartridge can be reduced. Another object of the present invention is to provide an ink cartridge detection mechanism, an inkjet printer, and an ink cartridge that can prevent misidentification of an attached / detached state due to dirt on a reflecting portion or ambient light. [0014]<u style="single">[Means for solving problems]</u><u style="single">In order to achieve the above object, the ink cartridge detection mechanism of the present invention is an ink cartridge detection mechanism that detects the attachment / detachment state of the ink cartridge in the cartridge holder, irradiates the cartridge holder with light, and is based on the reflected light. A reflective optical sensor that detects the detached state of the ink cartridge, a reflective member that is fixedly provided to the cartridge holder and forms a reflected light path of the optical sensor, and an ink cartridge that is provided on the ink cartridge. When mounted on the cartridge holder, it includes a shielding portion that shields the optical path of the optical sensor, and an accommodating portion that can accommodate the reflecting member and one side surface portion forms the shielding portion.</u>When the ink cartridge is mounted on the cartridge holder, the ink cartridge is provided with a locking mechanism for locking the ink cartridge at a predetermined position on the cartridge holder, and the locking mechanism is provided and mounted on the cartridge holder. A locking portion for locking the ink cartridge and a locked portion provided on the ink cartridge and locked by the locking portion of the cartridge holder are provided, and the locking portion has a first slope and a first slope. It has a substantially V-shape with two slopes, one end is formed at the other end of a plate-shaped elastic member fixed to the cartridge holder, and the locked portion is the locking portion. The ink cartridge is formed in a protruding shape so as to be in contact with the first and second slopes of the above, and the ink cartridge has the shielding portion in a state where the locked portion is in contact with the first slope of the locking portion. Does not block the optical path of the optical sensor, and it is preferable that the shielding portion shields the optical path of the optical sensor in a mounted state in which the locked portion is in contact with the second slope of the locking portion. ..<u style="single">Here, the optical path of the optical sensor shielded by the shielding portion is an optical path of the irradiation light from the optical sensor and / or an optical path of the reflected light from the reflecting portion of the cartridge holder. That is, the optical path that can be formed by the optical sensor and the reflecting portion of the cartridge holder is shielded. If both the irradiation optical path and the reflected optical path are shielded, it is effective in preventing misidentification of the attached / detached state due to dirt on the reflecting portion and ambient light.</u><u style="single"> Further, since the reflective portion is not provided in a fixed manner, the structure cannot be simplified as compared with the case where the reflective portion is formed of a movable member, and the reliability of attachment / detachment detection can be improved.</u><u style="single"> Further, since the reflective portion is covered by the accommodating portion when the ink cartridge is mounted, it is possible to reliably prevent the reflective portion from becoming dirty during the printing operation.</u><u style="single"> Furthermore, even if ambient light is incident without the ink cartridge installed, it does not affect the attachment / detachment detection result, and when the ink cartridge is installed, the reflective member is surely covered by the accommodating portion, so that the reflective member becomes dirty. False positives due to the above can be prevented.</u>[0015] Further, it is preferable that the cartridge holder and the optical sensor are relatively movable. Further, the cartridge holder has a plurality of reflecting portions arranged along the relative movement direction of the optical sensor.<u style="single">Material</u>It is preferable to provide. In this case, the same optical sensor can detect the attachment / detachment state of a plurality of ink cartridges. [0016] Further, the ink cartridge is a reflective unit for detecting the remaining amount of ink, which enables the detection of the remaining amount of ink by the optical sensor.<u style="single">Material</u>It is preferable to further provide.<u style="single">This</u>In the case of, the same optical sensor can detect the detached state of the ink cartridge and the remaining amount of ink. [0017] Further, in order to achieve the above object, the inkjet printer of the present invention is configured to include any of the ink cartridge detection mechanisms described above. [0018] Further, the ink cartridge of the present invention for achieving the above object is fixed so as to project from a reflective optical sensor that moves relative to the ink cartridge, a cartridge holder to which the ink cartridge is mounted, and the cartridge holder. This is an ink cartridge used in an inkjet printer provided with a reflective member formed so as to be able to reflect the irradiation light from the optical sensor in a state where the ink cartridge is not attached, and stores ink. An ink storage chamber, a reflective member for detecting the remaining amount of ink, which forms a reflected light path of light from the optical sensor and enables detection of the remaining amount of ink, and a reflective member of the cartridge holder when attached to the cartridge holder. Irradiation light from the optical sensor to the reflecting member and<u style="single">Before</u>A shielding portion capable of shielding the reflected light from the reflective member to the optical sensor and an accommodating portion capable of accommodating the reflective member when mounted on the cartridge holder are provided, and one side surface portion of the accommodating portion is the above-mentioned accommodating portion. It is configured by forming a shielding portion. [0021] [0021] In addition, the above<u style="single">Containment section</u>Said<u style="single">Anti</u>Shooting part<u style="single">Material</u>Formed along the outer shape of<u style="single">In the recess</u>Is preferable. [0022] Further, it is preferable that the recess is formed so as to hollow out a part of the surface of the ink cartridge on the mounting direction side to the cartridge holder. [0024] BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic side view showing the internal structure of the printer, and FIG. 2 is a schematic plan view showing the internal structure of the printer. As shown in these figures, an insertion slot 11 for manually inserting the paper P is formed on the front surface of the printer 10, while the paper P after printing is ejected on the upper surface of the printer 10. Outlet 12 is formed. Inside the printer 10, a side-view V-shaped paper path 13 from the insertion port 11 to the discharge port 12 is formed, and a paper feed roller pair 14 and a print head 15 are arranged on the paper path 13. To. The paper feed roller pair 14 includes a paper feed roller 16 and a paper presser roller 17 that face each other across the paper path 13, and the paper P is sandwiched and conveyed according to the drive rotation of the paper feed roller 16. The print head 15 is mounted on a carriage 18 that reciprocates in the width direction (horizontal direction in FIG. 2) of the paper path 13, and performs dot matrix printing on the paper P whose position is defined by the platen 19. The printing method of the print head 15 is an inkjet method of forming characters and images on the paper P by ejecting ink, and the ink used for printing is transferred from the ink supply unit 20 provided at the rear of the printer 10 to the print head 15. Be supplied. [0025] The carriage 18 is supported by a pair of front and rear guide shafts 21 and 22 so as to be movable left and right, and is forcibly moved according to the drive of the carriage moving mechanism 23. The carriage moving mechanism 23 includes a cam shaft 24 arranged in parallel below the front guide shaft 21, and a carriage motor 26 for rotationally driving the cam shaft 24 via a reduction gear train 25. A spiral cam groove (not shown) is formed on the outer peripheral surface of the cam shaft 24, and a cam follower 27 extending from the carriage 18 is engaged with the spiral cam groove (not shown). When the cam shaft 24 rotates in response to the drive of the carriage motor 26, the cam follower 27 is fed in the axial direction by the spiral feeding action of the cam groove. As a result, the carriage 18 can be moved in the left-right direction according to the forward / reverse drive of the carriage motor 26. [0026] FIG. 3 is a perspective view of a carriage equipped with a print head. As shown in this figure, the print head 15 is mounted on top of the carriage 18. A flexible flat cable 28 and an ink tube 29 are pulled out from one side of the print head 15, and ink is supplied from the ink supply unit 20 to the print head 15 via the ink tube 29. .. The carriage 18 has a sensor mounting portion 18a extending downward from the rear portion, and on the rear surface of the sensor mounting portion 18a, a light emitting element 30a that irradiates light rearward and a light receiving element 30b that receives the reflected light thereof. A reflective optical sensor 30 with and is attached. [0027] FIG. 4 is a front view of the ink supply unit showing the ink cartridge not installed state, FIG. 5 is a front view of the ink supply unit showing the ink cartridge installed state, and FIG. 6 is an ink supply unit showing the ink cartridge not installed state. A perspective view, FIG. 7 is a perspective view of an ink supply unit showing an ink cartridge mounted state, and FIG. 8 is a perspective view of the ink cartridge as viewed from below. As shown in these figures, the ink supply unit 20 includes a cartridge holder 31 provided on the inner rear side of the printer 10 and two ink cartridges 32A that are detachably attached to the cartridge holder 31 from above. , 32B and is configured. Inside the ink cartridge 32A, an ink storage chamber 34A that stores secondary color inks (for example, color inks such as red, green, and blue) and appropriately discharges them from the bottom ink discharge port 33A, and an ink recovery port at the bottom. A partition is formed with a waste ink storage chamber 36 for storing waste ink sent from 35. When the ink cartridge 32A is mounted in the predetermined position of the cartridge holder 31, the ink discharge port 33A and the ink recovery port 35 communicate with the connection ports 37A and 38 formed at the bottom of the cartridge holder 31, respectively, to supply secondary color ink and Waste ink can be collected. On the other hand, inside the ink cartridge 32B, an ink storage chamber 34B is formed which stores the main color ink (for example, black ink) and appropriately discharges the main color ink (for example, black ink) from the ink discharge port 33B at the bottom. When the ink cartridge 32B is mounted at a predetermined position on the cartridge holder 31, the ink discharge port 33B communicates with the connection port 37B formed on the bottom of the cartridge holder 31 to supply the main color ink. [0028] The ink cartridges 32A and 32B are arranged so as to be arranged along the moving direction of the carriage 18 (optical sensor 30). In the front portions of the ink cartridges 32A and 32B, prism-shaped reflecting members (reflecting portions for detecting the remaining amount of ink) 39A and 39B having light transmission are provided on the portions facing the moving path of the optical sensor 30. The reflecting members 39A and 39B have a right-angled triangular prism shape, and the two prism reflecting surfaces S1 and S2 forming a right angle to each other are projected inside the ink storage chambers 34A and 34B. As shown in FIG. 9, when the optical sensor 30 is moved to the opposite position of the reflecting members 39A and 39B and irradiated with light, the irradiated light passes through the inside of the reflecting members 39A and 39B and is a prism. It is sequentially reflected by the reflecting surfaces S1 and S2, and is incident on the light receiving element 30b of the optical sensor 30. The reflectance (refractive index) of the prism reflecting surfaces S1 and S2 is lower when the ink remaining level in the ink storage chambers 34A and 34B is higher than that of the prism reflecting surfaces S1 and S2, while it is lower than that of the prism reflecting surfaces S1 and S2. If it is low, it will be high. That is, as shown in FIG. 9A, when the prism reflecting surfaces S1 and S2 are in contact with the ink, the irradiation light of the optical sensor 30 is absorbed by the ink and the reflectance (intensity of the reflected light) is increased. As shown in (B) of FIG. 9, when the prism reflecting surfaces S1 and S2 are in contact with air, the light is not absorbed by the ink and the reflectance (intensity of reflected light) becomes high. This makes it possible to detect the remaining amount of ink (presence or absence of ink at a predetermined level) of the ink cartridges 32A and 32B based on the detection value of the light receiving element 30b in the optical sensor 30. [0029] Two reflective members (reflective portions for attachment / detachment detection) 40A and 40B arranged along the moving direction of the carriage 18 (optical sensor 30) are fixed to the bottom of the cartridge holder 31 in a posture of projecting upward. The reflecting members 40A and 40B have a prism portion 40a having a right-angled triangular prism shape having light transmission, and the two prism reflecting surfaces S3 and S4 forming a right angle with each other are the reflecting members 39A and 39B for detecting the remaining amount of ink. Similarly, the reflected light path of the optical sensor 30 is formed. On the other hand, recesses (drilled portions) 41A and 41B are integrally formed at the lower portions of the ink cartridges 32A and 32B. When the ink cartridges 32A and 32B are mounted in the predetermined positions of the cartridge holder 31, the reflective members 40A and 40B are fitted into the recesses 41A and 41B, and the periphery thereof is covered. At this time, the shielding portions 42A and 42B integrally formed on one side surface portion (optical sensor facing wall portion) of the recesses 41A and 41B intervene between the optical sensor 30 and the reflecting members 40A and 40B, and reflect the optical sensor 30 and the reflecting member 40A and 40B. The optical path (irradiation optical path and reflected optical path) between the members 40A and 40B is blocked. [0030] As shown in FIG. 9C, the reflective members 40A and 40B are exposed when the ink cartridges 32A and 32B are not mounted on the cartridge holder 31. In this state, when the optical sensor 30 is moved to the opposite positions of the reflecting members 40A and 40B and light is irradiated there, the irradiated light passes through the inside of the reflecting members 40A and 40B and is transmitted through the prism reflecting surfaces S3 and S4. Is sequentially reflected and incident on the light receiving element 30b of the optical sensor 30. On the other hand, as shown in FIGS. 9A and 9B, when the ink cartridges 32A and 32B are mounted on the cartridge holder 31, the front of the reflective members 40A and 40B is covered by the shielding portions 42A and 42B. .. In this state, when the optical sensor 30 is moved to the opposite positions of the reflecting members 40A and 40B and the light is irradiated there, the irradiated light is shielded by the shielding portions 42A and 42B, and the reflecting members 40A and 40B are extended. It does not reach the light receiving element 30b of the optical sensor 30. As a result, the optical sensor 30 can detect the attachment / detachment state of the ink cartridges 32A and 32B without providing the ink cartridges 32A and 32B with a reflective member for attachment / detachment detection. Further, as described above, when the ink cartridges 32A and 32B are not attached to the cartridge holder 31, the light receiving element 30b of the optical sensor 30 is always in the light receiving state, so that it is assumed that ambient light is incident on the light receiving element 30b. However, it does not affect the attachment / detachment detection result of the ink cartridges 32A and 32B. Further, when the ink cartridges 32A and 32B are mounted on the cartridge holder 31, the reflective members 40A and 40B are covered by the recesses 41A and 41B. Therefore, even if the ink is scattered during the printing operation, the reflective members 40A and 40B are covered. As a result, it is possible to prevent erroneous detection due to dirt on the reflective members 40A and 40B. [0031] FIG. 10 is a XX cross-sectional view of the ink supply unit showing the ink cartridge mounting state, and FIG. 11 is a YY cross-sectional view of the ink supply unit showing the ink cartridge temporary mounting state. As shown in these figures, two lock plates 43A and 43B are erected at the rear of the cartridge holder 31. The lock plates 43A and 43B are plate-shaped elastic members, and dog-shaped (V-shaped) locking portions 44A and 44B are formed at the upper ends thereof. When the ink cartridges 32A and 32B are placed on the cartridge holder 31 from above, as shown in FIG. 11, the convex portions 45A and 45B protruding from the rear surface of the ink cartridges 32A and 32B are the lock plates 43A and 43B. The ink cartridges 32A and 32B are temporarily mounted on the locking portions 44A and 44B. At this time, the shielding portions 42A and 42B of the ink cartridges 32A and 32B are located above the prism portions 40a of the reflecting members 40A and 40B, and the optical path between the optical sensor 30 and the reflecting members 40A and 40B is shielded. Not done. Further, when the ink cartridges 32A and 32B are pushed downward in the temporarily mounted state, the lock plates 43A and 43B are pushed by the convex portions 45A and 45B to temporarily retract and rotate backward, and then the convex portions 45A and 45B are moved. When it gets over it, it returns and rotates forward. When the lock plates 43A and 43B return and rotate, as shown in FIG. 10, the locking portions 44A and 44B engage with the upper portions of the convex portions 45A and 45B, and the ink cartridges 32A and 32B are held in the mounting position (locking). ). At this time, the shielding portions 42A and 42B of the ink cartridges 32A and 32B intervene between the prism portions 40a of the reflecting members 40A and 40B and the optical sensor 30, and the optical path of the optical sensor 30 is shielded. [0032] As described above, according to the present embodiment, the printer 10 irradiates light toward the cartridge holder 31, and detects the detached state of the ink cartridges 32A and 32B based on the reflected light, and the reflective optical sensor 30. When the reflective members 40A and 40B provided on the cartridge holder 31 and forming the reflected light path of the optical sensor 30 and the ink cartridges 32A and 32B provided on the ink cartridges 32A and 32B are mounted on the cartridge holder 31, the optical sensor 30 It is configured to be provided with shielding portions 42A and 42B that shield the optical path of the above. That is, while the reflective optical sensor 30 detects the detached state of the ink cartridges 32A and 32B, it is not necessary to provide the reflective portion for the detached detection on the ink cartridges 32A and 32B, and the ink cartridges 32A and 32B are used. It is not possible to reduce the cost, and it is possible to prevent misidentification of the attached / detached state due to dirt on the reflecting portion and ambient light. [0033] Further, since the reflective members 40A and 40B are fixed members integrally provided on the bottom of the cartridge holder 31, the structure can be simplified as compared with the case where the reflective members 40A and 40B are composed of movable members. It is possible to improve the reliability of attachment / detachment detection. [0034] Further, since the shielding portions 42A and 42B are integrally formed under the ink cartridges 32A and 32B, the number of parts and the manufacturing process of the ink cartridges 32A and 32B can be reduced. [0035] Further, since the ink cartridges 32A and 32B are provided with recesses 41A and 41B that cover the reflective members 40A and 40B when mounted on the cartridge holder 31, one side surface portion of the recesses 41A and 41B forms the shielding portions 42A and 42B. , The reflective members 40A and 40B can be protected when the ink cartridge is attached, and detection defects due to dirt and scratches on the reflective members 40A and 40B can be prevented. [0036] Further, the shielding portions 42A and 42B print with the ink cartridges 32A and 32B temporarily attached because they do not block the optical path of the optical sensor 30 when the ink cartridges 32A and 32B are temporarily attached to the cartridge holder 31. It is possible to avoid troubles such as operation being performed. [0037] Further, since the cartridge holder 31 and the optical sensor 30 are relatively movable, the same optical sensor 30 can be used to detect the attachment / detachment state of a plurality of ink cartridges 32A and 32B, and to check the remaining amount of ink in the ink cartridges 32A and 32B. It becomes possible to detect. [0038] Further, since the cartridge holder 31 includes a plurality of reflective members 40A and 40B arranged along the relative movement direction of the optical sensor 30, the same optical sensor 30 can detect the attachment / detachment state of the plurality of ink cartridges 32A and 32B. Can be done. [0039] Further, since the ink cartridges 32A and 32B are provided with reflective members 39A and 39B for detecting the remaining amount of ink by the optical sensor 30, the same optical sensor 30 can be used to detect the remaining amount of ink in the ink cartridges 32A and 32B. It is possible to detect the detached state and the remaining amount of ink. [0040] Although one embodiment of the present invention has been described above with reference to the drawings, the present invention is not limited to the matters shown in the above-described embodiment, and the scope of claims, the description of the detailed description of the invention, and well-known techniques Includes the scope in which those skilled in the art can make changes and applications based on. [0041] For example, in the above-described embodiment, one side surface of the recess integrally formed with the ink cartridge is used as a shielding portion, but any one that can shield the optical path of the optical sensor 30 when mounted on the cartridge holder may be used. For example, the shielding portion may be integrally formed on one side surface of the ink cartridge in a hook shape (L shape). [0042] Further, in the above-described embodiment, the ink cartridge is mounted on the printer main body side, but the present invention can also be carried out in a printer in which the ink cartridge is mounted on the carriage. That is, if a reflective member is provided on the cartridge holder mounted on the carriage and this is detected by an optical sensor arranged on the printer main body side, the same effect as that of the above embodiment can be obtained. [0043] [Effect of the invention] As described above, according to the present invention, while the reflective optical sensor detects the attachment / detachment state of the ink cartridge, it is not necessary to provide the ink cartridge with a reflective portion for detection of attachment / detachment, and the cost of the ink cartridge is reduced. However, it is possible to prevent misidentification of the attached / detached state due to dirt on the reflecting portion and ambient light. [Simple explanation of drawings] FIG. 1 is a schematic side view showing an internal structure of a printer. FIG. 2 is a schematic plan view showing the internal structure of the printer. FIG. 3 is a perspective view of a carriage equipped with a print head. FIG. 4 is a front view of an ink supply unit showing an ink cartridge non-installed state. FIG. 5 is a front view of an ink supply unit showing an ink cartridge mounted state. FIG. 6 is a perspective view of an ink supply unit showing a state in which an ink cartridge is not installed. FIG. 7 is a perspective view of an ink supply unit showing an ink cartridge mounted state. FIG. 8 is a perspective view of the ink cartridge as viewed from below. FIG. 9 is an explanatory diagram showing detection of attachment / detachment of an ink cartridge and detection of remaining amount of ink. FIG. 10 is a cross-sectional view taken along the line XX of an ink supply unit showing an ink cartridge mounted state. FIG. 11 is a YY cross-sectional view of an ink supply unit showing an ink cartridge temporarily mounted state. [Explanation of symbols] 10 printer 15 print head 18 carriage 20 Ink supply unit 30 optical sensor 30b light receiving element 30a light emitting element 31 Cartridge holder 32A, 32B ink cartridge 39A, 39B Reflective member (for detecting ink level) 40A, 40B Reflective member (for attachment / detachment detection) 41A, 41B recess 42A, 42B shield 43A, 43B lock plate