Patent Publication Number: US-6663213-B2

Title: Method and device for verifying coloring agent cartridge for printer

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a method and device for verifying a coloring agent cartridge for a printer, in which it is determined whether or not a replaceable coloring agent cartridge loaded in a printer is genuine. 
     2. Description of the Related Art 
     Generally, replaceable ink cartridges or toner cartridges are loaded in a printer. For example, when an ink is completely consumed in a color printer, a corresponding one of the black and color ink cartridges, or a single unit cartridge containing all colors can be replaced. 
     When this type of coloring agent cartridge is replaced, a non-genuine cartridge may be loaded in the main body of the printer instead of a genuine cartridge. However, conventionally the main body has not had a function for verifying the loaded cartridge. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a method and device for verifying a coloring agent cartridge for a printer, in which verification can be easily performed even when a loaded non-genuine coloring agent cartridge cannot be distinguished merely by its appearance. 
     In order to achieve the above described object, the inventors of the present invention have directed their attention to that, the following principle: an amorphous alloy material generates magnetization noise due to the Barkhausen effect, that is, a magnetic pulse, at a predetermined magnetic level, is used to verify a magnetic card and so on. 
     According to an aspect of the present invention, a method for verifying a replaceable coloring agent cartridge loaded in a printer comprises providing an amorphous magnetic member on a genuine coloring agent cartridge to be loaded in a main body; providing, in the main body, an exciting coil for exciting the amorphous magnetic member in an AC magnetic field and a detecting coil for detecting the AC magnetic field passing through the amorphous magnetic member; and verifying the coloring agent cartridge based on whether or not a magnetic pulse which is generated at a predetermined level of the AC magnetic field and which is superimposed on a detection signal of the detecting coil is generated at a predetermined phase position in a period of the AC magnetic field. 
     It is determined that the magnetic pulse is superimposed on the predetermined phase position in the period of the AC detection signal corresponding to the AC magnetic field, when the detecting coil detects the AC magnetic field passing through the amorphous magnetic member attached to or embedded in the genuine coloring agent cartridge. The amorphous magnetic member may be in the form of a piece, line, film, or powder. If the cartridge is non-genuine, the magnetic pulse is not generated. Even if the amorphous magnetic member is attached, the magnetic pulse is not generated at the predetermined phase position in the period of the AC magnetic field, and thus the cartridge is determined to be non-genuine. A non-genuine ink cassette can be easily detected because it is difficult to fabricate the same type of amorphous magnetic members. 
     By verifying the coloring agent cartridge based on pattern recognition such as the amplitude and pulse width of the magnetic pulse, in addition to whether or not the magnetic pulse is generated at the predetermined phase position in the period of the AC magnetic field, the verification accuracy is further increased. 
     According to another aspect of the present invention, a device for verifying a replaceable coloring agent cartridge loaded in a printer comprises an amorphous magnetic member provided on the coloring agent cartridge loaded in a main body; an exciting coil for exciting the amorphous magnetic member in an AC magnetic field and a detecting coil for detecting the AC magnetic field passing through the amorphous magnetic member, the coils being provided in the main body; a verifying unit for verifying the coloring agent cartridge based on whether or not a magnetic pulse which is generated at a predetermined level of the AC magnetic field and which is superimposed on a detection signal of the detecting coil is generated at a predetermined phase position in a period of the AC magnetic field; and a print preventing unit for stopping the operation of the printer so that printing cannot be performed when the coloring agent cartridge is determined to be non-genuine. With this configuration, a non-genuine ink cassette can be easily detected and a printing operation is automatically prevented when the non-genuine cartridge is loaded. 
     In a color printer in which a plurality of replaceable coloring agent cartridges can be loaded, at least the detecting coil is provided for each of the coloring agent cartridges, the detecting coils being arranged in parallel. That is, the exciting coil is provided for all or each of the cartridges, and the detecting coil is provided for the respective cartridges. 
     In a color printer in which a plurality of replaceable coloring agent cartridges can be loaded in a print head, which moves in the line direction, one exciting coil and one detecting coil are provided along a transport path of the print head so as to scan and verify the plurality of coloring agent cartridges in order when the print head moves in the line direction. 
     In a color printer in which a plurality of replaceable coloring agent cartridges can be loaded, one exciting coil and one detecting coil are provided so as to move on a rail placed along the alignment direction of the plurality of coloring agent cartridges so as to scan and verify the plurality of coloring agent cartridges in order. 
     The device further comprises a magnetic pulse extracting unit for extracting the magnetic pulse superimposed on the detection signal of the detecting coil. Also, the verifying unit verifies the coloring agent cartridge based on pattern recognition such as the amplitude and pulse width of the magnetic pulse, in addition to whether or not the extracted magnetic pulse is generated at the predetermined phase position in the period of the AC magnetic field. With this arrangement, the verification accuracy is increased. 
     The verifying unit verifies the coloring agent cartridge when it is detected that the coloring agent cartridge is loaded in the main body. Accordingly, the verification is automatically performed when the coloring agent cartridge is replaced. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows the configuration of a device for verifying an ink cartridge according to an embodiment of the present invention; 
     FIG. 2 is a perspective view showing a print head part of the device; 
     FIGS. 3A and 3B show a magnetic pulse generated in the device; 
     FIG. 4 shows the configuration of a device for verifying an ink cartridge according to another embodiment; 
     FIG. 5 is a perspective view showing ink cassettes to be verified by the device shown in FIG. 4; and 
     FIG. 6 shows the configuration of a device for verifying a toner cartridge according to still another embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, a device for performing a method for verifying a coloring agent cartridge for a color inkjet printer according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG. 2, a color printer  1  includes a print head  8  which is driven in a reciprocating manner in the line direction of the color printer  1 . A replaceable black ink cartridge  2  and color ink cartridge  3  including five colors of ink, such as cyan, magenta, etc., are set in the print head  8 . Further, the ink cartridges  2  and  3  are covered with attached lids  4  and  5 , respectively, and claws  4   b  and  5   b  are provided to be engaged with hooks  4   a  and  5   a , respectively, so as to be locked. 
     As shown in FIG. 1, the back surfaces of the genuine ink cartridges  2  and  3  are provided with linear thin-film amorphous magnetic members  9  and  9   a , respectively, which cause changes in magnetization by the Barkhauzen effect in a magnetized region just before saturation. The alloy material and the manufacturing method of the amorphous magnetic members are selected in advance so that the members have a specific magnetic characteristic. An exciting coil  10 , which is placed close to and in parallel with the amorphous magnetic members  9  and  9   a  of the ink cartridges  2  and  3  loaded in the print head  8  and which excites the amorphous magnetic members  9  and  9   a  by an AC magnetic field, and detecting coils  19  and  19   a  for detecting the AC magnetic field passing through each of the amorphous magnetic members  9  and  9   a  are provided in a region of a main body  11   a , the region facing the print head  8  at a stop position. 
     An exciting signal generating unit  11  supplies a sine-wave signal, having an amplitude for generating a magnetic pulse at a predetermined phase position with respect to the amorphous magnetic members  9  and  9   a , to the exciting coil  10 . A magnetic pulse extracting unit including preamplifiers  12  and  12   a  and differential amplifiers  13  and  13   a  is connected to the detecting coils  19  and  19   a . That is, the sine-wave reference signal is supplied from the exciting signal generating unit  11  to the differential amplifiers  13  and  13   a  as one input signal and a detection signal (FIG. 3A) is also supplied as the other input signal. Further, a superimposed magnetic pulse P 1  is extracted as a difference signal (FIG.  3 B). 
     A verifying unit  15  verifies the cartridge based on whether or not a normal magnetic pulse P 1  is extracted from the differential output signals from the detecting coils  19  and  19   a , that is, whether or not the magnetic pulse P 1  is generated at a predetermined phase position with respect to an AC period corresponding to the AC magnetic field, and on pattern recognition whether or not the pulse width and the amplitude correspond to a predetermined waveform A head-transport control unit  17 , which controls the transport of the print head  8  in the line direction during printing, receives a lock signal which is generated when an attached sensor detects that the ink cartridges  2  and  3  are installed and the claws  4   b  and  5   b  are engaged with the hooks  4   a  and  5   a , and generates a start signal when the print head  8  is at the stop position so as to operate the verifying unit  15 . 
     When the magnetic pulse P 1  is not extracted at the predetermined phase position of the detection signal of at least one of the detecting coils  19  and  19   a , or when the magnetic pulse P 1  is extracted and is determined not to be a normal pattern by the verifying unit  15 , a print preventing unit  16  responds to the determination signal and controls the head-transport control unit  17  to stop the operation of the print head  8  in the line direction so that printing cannot be performed. 
     Now, the operation of the device for verifying an ink cartridge for a color printer will be described. When the black ink cartridge  2  or the color ink cartridge  3  or both cartridges  2  and  3  are replaced, and when it is detected that the lids  4  and  5  is locked, the exciting coil  10  excites the amorphous magnetic members  9  and  9   a  in the AC magnetic field for a predetermined time at the stop position of the print head  8 . At that time, it is determined whether or not the normal magnetic pulse P 1  is extracted from the detecting coils  19  and  19   a.    
     When the magnetic pulse P 1  extracted from both of the detecting coils  9  and  9   a  is determined to be normal, the color printer  1  operates normally. When one of the ink cartridges  2  and  3  or both of them are replaced by a non-genuine cartridge, the magnetic pulse is not extracted if the amorphous magnetic member is not provided on the cartridge. Also, when a non-genuine amorphous magnetic member is attached, the magnetic pulse is not generated at the predetermined phase position if the type of member is different. Even if a magnetic pulse is generated, the waveform or amplitude does not match. Accordingly, the verifying unit  15  controls the head-transport control unit  17  so as to operate the print preventing unit  16  so that printing cannot be performed. 
     In this embodiment, the detecting coil is attached to each of the black ink cartridge  2  and the color ink cartridge  3  and one common exciting coil is used for both cartridges  2  and  3 . However, two exciting coils may be provided for the respective cartridges  2  and  3 . 
     FIGS. 4 and 5 show a device for verifying an ink cartridge according to another embodiment. In this embodiment, a linear thin-film amorphous magnetic member  31  is attached to the bottom surface of each of six ink cartridges  30  in which coloring agent can be separately replaced. An exciting coil  10  and a detecting coil  19  are provided in the region of the main body, facing the innermost ink cartridge  30  at the stop position of the print head  8 . When any of the ink cartridges  30  is replaced, the head-transport control unit  17  reciprocates the print head  8  for a test in response to the lid lock signal and operates a verifying unit  25 , which has the same function as in the foregoing embodiment, when each of the ink cartridges  30  moves to the position of the innermost ink cartridge  30 , one after another. Accordingly, the amorphous magnetic members  31  of all the ink cartridges  30  are excited and scanned. When a normal magnetic pulse is not detected when facing any of the ink cartridges  30 , the print preventing unit  16  is operated so that printing cannot be performed. 
     In the above-described embodiments, the present invention is applied to a color inkjet printer. However, the present invention can be applied to a laser printer in which a replaceable toner cartridge is loaded. In this case, as shown in FIG. 6, a scanning head  40  including an exciting coil and a detecting coil is mounted on a rail  42  placed along the alignment direction of four fixed toner cartridges  41  including cyan, magenta, yellow, and black. The scanning head  40  can move on the rail  42 . A linear thin-film amorphous magnetic member  49  is embedded in the bottom surface of each of the toner cartridges  41  so as to be parallel with the scanning head  40 . Accordingly, when the replacement of any of the toner cartridges  41  is detected, a transport control unit  45  drives the scanning head  40  and the scanning head  40  scans the toner cartridges  41  in order from the end so that the determination is performed. A verifying unit  47  responds to the timing signal of the transport control unit  45  and verifies the amorphous magnetic member  49  of the toner cartridge  41  which has moved to the determination position based on the extraction signal of a magnetic pulse extracting unit  46 , in the method as described above. When a normal magnetic pulse is not detected, a print preventing unit  48  operates so that printing cannot be performed.